Articoli di riviste: "Result measurement in HR"

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Witkowski, Michał, Andrzej Bissinger, Magdalena Witkowska, Piotr Smolewski e Andrzej Lubiński. "Evaluation of the usefulness of smartphone-directed applications for measuring heart rate and arrhythmia detection". Postępy Higieny i Medycyny Doświadczalnej 71 (13 dicembre 2017): 0. http://dx.doi.org/10.5604/01.3001.0010.7012.

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Introduction: There are many available applications for smartphones to measure heart rate (HR) based on a finger pulse wave, without any additional devices. An important feature of the application should be the possibility to detect arrhythmia, especially atrial fibrillation (AF). The purpose of this study was to evaluate the utility of HR measurement applications, available for smartphones, in terms of the reliability of the measurements and the possibilities for arrhythmia detection. Material/Methods: From the free applications available on smartphones with the iOS operating system we selected all (N=16), which offer HR measurement and a simultaneous graphical pulse wave recording. The HR was examined in 15 healthy volunteers with a sinus rhythm confirmed in ECG. The next step was to evaluate the reliability of HR measurement in 15 patients with AF. Results: The average difference in the HR was 6% (0.6%-33%), while a difference below 5% was observed in 11 applications. According to our study, the most reliable applications to measure HR in patients with sinus rhythm was Instant Heart Rate by Azumio company. Five most reliable applications have been selected to test in patients with AF. We have chosen this application according to the most reliable HR measurement (<5%), best graphic pulse wave recording and the ability to view the recording at the end of the measurement. Only 1 of 5 applications - Heart Rate from Bump company - had >95% HR compatibility with ECG (the measurement difference was 0.88 %). Conclusions: The majority of the free applications, available for smartphones, are able to measure HR precisely in patients with sinus rhythm, while in patients with AF, the exact measurement is significantly impeded by HR deficits. Only one out of 16 applications was able to measure HR in a patient with AF. None of the available applications could detect AF.

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Wu, Han, Tao Wang, Tuo Dai, Xiaoyu Wang, Yuanzhen Lin e Yizhou Wang. "Let home nursing assistant robots see your heart rate". International Journal of Crowd Science 2, n. 3 (3 settembre 2018): 198–211. http://dx.doi.org/10.1108/ijcs-09-2018-0023.

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Purpose This paper aims to design a vision-based non-contact real-time accurate heart rate (HR) measurement framework for home nursing assistant. Design/methodology/approach The study applied Second-Order Blind Signal Identification (SOBI) algorithm to extract remote HR signal and analyzed it with Fast Fourier Transform (FFT). Multiple regions of interest are chosen and analyzed to obtain a more accurate result. Findings An accurate non-contact hear rate (HR) measurement framework is proposed and proved to be efficient. Originality/value The contributions of this HR measurement framework are as follows: accurate measurement of HR, real-time performance, robust under various scenes such as conversation, lightweight computation which is suitable and necessary for home nursing assistance. This framework is designed to be flexibly used in various real-life scenes such as domestic health assistance and affectively intelligent agents and is proved to be robust under such scenes.

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Rosa, Dayana P., Paula R. Camargo e John D. Borstad. "Effect of Posterior Capsule Tightness and Humeral Retroversion on 5 Glenohumeral Joint Range of Motion Measurements: A Cadaveric Study". American Journal of Sports Medicine 47, n. 6 (maggio 2019): 1434–40. http://dx.doi.org/10.1177/0363546519840006.

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Background: Altered glenohumeral joint range of motion can be caused by increased humeral retroversion (HR) and/or posterior capsule tightness (PCT). To make informed clinical decisions, it is vital to understand how HR and PCT alterations, individually and in combination, affect joint range of motion measurements. Purpose: To evaluate the effect of experimental tissue alterations on clinical range of motion measures. Study Design: Controlled laboratory study. Methods: Five clinical measurements were quantified in 8 fresh-frozen cadavers under 4 experimentally created conditions: baseline (no alterations), HR condition (20° increase in HR by transecting the bone), PCT condition (20% decrease in length via thermal energy), and PCT + HR combined. Clinical measurements included bicipital forearm angle, low flexion, glenohumeral internal and external rotation, and horizontal adduction. All measurements were taken by the same blinded tester. Separate 1-factor repeated measures analyses of variance were used to evaluate the effect of the alterations on each clinical measurement. Results: There was a significant main effect of condition for bicipital forearm angle ( P = .02, F = 4.03), low flexion ( P = .02, F = 3.86), internal rotation ( P = .03, F = 3.65), and external rotation ( P < .001, F = 15.15) but not for horizontal adduction ( P = .29, F = 1.33). The HR condition resulted in a decreased bicipital forearm angle of 16.1° and 15.8° as compared with the PCT and PCT + HR conditions, respectively. When compared with baseline, the PCT + HR condition decreased the low flexion test by 13.5°, and the HR condition decreased internal rotation range of motion by 14.2°. All conditions increased external rotation when compared with baseline. Conclusion: Greater measurement changes were noted in both HR conditions, suggesting that bony alterations influence motion to a greater extent than posterior capsule alterations. Clinical Relevance: Clinicians should be aware that humeral retroversion will influence the measurement of posterior shoulder tightness.

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De Bernardo, Maddalena, Palmiro Cornetta, Giuseppe Marotta, Giulio Salerno, Ilaria De Pascale e Nicola Rosa. "Measurement of corneal thickness using Pentacam HR versus Nidek CEM-530 specular microscopy". Journal of International Medical Research 48, n. 4 (26 dicembre 2019): 030006051989238. http://dx.doi.org/10.1177/0300060519892385.

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Objective To compare corneal thickness (CT) measurements using the CEM-530 (Nidal, Gamagori, Japan) and Pentacam HR (Oculus, Wetzlar, Germany). Methods The CT of 209 healthy subjects (209 right eyes) aged 24 to 89 years (71.35 ± 10.72 years) was measured at the corneal apex (CA), pupil center (PC), and thinnest point (TP) with the Pentacam HR and at the corneal center with the CEM-530 in random order at the same time of day. Results A good correlation but statistically significant difference was found between the CEM-530 and Pentacam HR measurements at the CA (6.10 ± 8.12 µm, R2 = 0.8947), PC (7.46 ± 8.57 µm, R2 = 0.8826), and TP (12.44 ± 10.04 µm, R2 = 0.8392). Comparison of the two devices produced the following regression formulas: y = 0.8859x + 57.644 for the CA, y = 0.8852x +56.657 for the PC, and y = 0.8557x + 68.148 for the TP, where x is the CT obtained with the CEM-530 and y is that obtained with the Pentacam HR. Conclusions These findings indicate that the CEM-530 produces a thicker corneal measurement than the Pentacam HR. The herein-proposed correcting factors are needed to reliably compare these devices.

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Huang, Gangqin, Zhangfa Yan, Tiantian Dai, Ren-Guey Lee e Qingyang Wei. "Simultaneous measurement of ionizing radiation and heart rate using a smartphone camera". Open Physics 18, n. 1 (23 settembre 2020): 566–73. http://dx.doi.org/10.1515/phys-2020-0181.

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AbstractComplementary metal oxide semiconductor (CMOS) cameras have been used to detect ionizing radiation when shaded from light or under the condition of static scenes. We propose a novel idea for simultaneous measurement of ionizing radiation and heart rate (HR) by using a smartphone with its CMOS camera lens covered by a finger in one measurement. Verified experiments were conducted: videos were recorded using a Xiaomi8 smartphone when the camera lens was covered by a finger and a light-tight tape for controlled experiment, with a ∼33 mCi 99mTc liquid radioactive source at six different distances (from 20 to 70 cm, step size 10 cm) from the camera. The exact HRs were measured using an oximeter at the same time. Image processing algorithm is proposed to extract radiation events and HR in the same videos. Results show that: (1) frame numbers containing radiation-related bright spots in two experiments have a linear relationship, and they are inversely proportional to the square of the distance between the camera and radiation source; (2) the HR difference between the video processing and the oximeter result is less than 2 beats per minute. In conclusion, it verifies that the proposed method is available to detect ionizing radiation and measure HR simultaneously with smartphone camera lens covered by a finger. We have been working on the development of an Android phone application based on the algorithms.

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ARYANTO, DIDIK, ZULKAFLI OTHAMAN, AMIRA S. AMERUDDIN e ABD KHAMIM ISMAIL. "AFM, HR-XRD AND PL CHARACTERIZATION OF STACKED STRUCTURES In0.5Ga0.5As/GaAs QUANTUM DOTS". Nano 05, n. 02 (aprile 2010): 127–32. http://dx.doi.org/10.1142/s1793292010002013.

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In0.5Ga0.5As quantum dots (QDs) stacked structure were studied using atomic force microscopy (AFM), high-resolution X-ray diffraction (HR-XRD) and photoluminescence (PL) characterization. Evolution in the dots size and dots density in the stacked structures is strongly influenced by the dot formation in the under-layer and the structure of the spacer layers. AFM results revealed that the dots formation on the top can be changed by increasing the number of stacked QDs. However, the dots formation is not vertically aligned since HR-XRD measurement gave different satellite peak on n-stacked QD structures. Room-temperature PL measurements show variation in the PL spectra, where blue-shifted PL peak positions are observed when the number of stack is increased. Variation in the HR-XRD and PL measurement is also attributed to the size, composition and density of the dots in the stacked structures.

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Goetze, Jens P., Linda M. Hilsted, Jens F. Rehfeld e Urban Alehagen. "Plasma chromogranin A is a marker of death in elderly patients presenting with symptoms of heart failure". Endocrine Connections 3, n. 1 (marzo 2014): 47–56. http://dx.doi.org/10.1530/ec-14-0017.

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Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk. Assessment of cardiovascular mortality during the first 3 years of observation showed that CgA measurement contained useful information with a hazard ratio (HR) of 5.4 (95% CI 1.7–16.4) (CgA confirm). In a multivariate setting, the corresponding HR was 5.9 (95% CI 1.8–19.1). When adding N-terminal proBNP (NT-proBNP) to the model, CgA confirm still possessed prognostic information (HR: 6.1; 95% CI 1.8–20.7). The result for predicting all-cause mortality displayed the same pattern. ROC analyses in comparison to NT-proBNP to identify patients on top of clinical variables at risk of cardiovascular death within 5 years of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality.

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Diebold, A. C., B. Foran, C. Kisielowski, D. A. Muller, S. J. Pennycook, E. Principe e S. Stemmer. "Thin Dielectric Film Thickness Determination by Advanced Transmission Electron Microscopy". Microscopy and Microanalysis 9, n. 6 (21 novembre 2003): 493–508. http://dx.doi.org/10.1017/s1431927603030629.

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High-resolution transmission electron microscopy (HR-TEM) has been used as the ultimate method of thickness measurement for thin films. The appearance of phase contrast interference patterns in HR-TEM images has long been confused as the appearance of a crystal lattice by nonspecialists. Relatively easy to interpret crystal lattice images are now directly observed with the introduction of annular dark-field detectors for scanning TEM (STEM). With the recent development of reliable lattice image processing software that creates crystal structure images from phase contrast data, HR-TEM can also provide crystal lattice images. The resolution of both methods has been steadily improved reaching now into the sub-Ångstrom region. Improvements in electron lens and image analysis software are increasing the spatial resolution of both methods. Optimum resolution for STEM requires that the probe beam be highly localized. In STEM, beam localization is enhanced by selection of the correct aperture. When STEM measurement is done using a highly localized probe beam, HR-TEM and STEM measurement of the thickness of silicon oxynitride films agree within experimental error. In this article, the optimum conditions for HR-TEM and STEM measurement are discussed along with a method for repeatable film thickness determination. The impact of sample thickness is also discussed. The key result in this article is the proposal of a reproducible method for film thickness determination.

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Phuphanin, Akkachai, Lawan Sampanporn e Boonsong Sutapun. "Smartphone-Based Device for Non-Invasive Heart-Rate Measurement of Chicken Embryos". Sensors 19, n. 22 (6 novembre 2019): 4843. http://dx.doi.org/10.3390/s19224843.

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Heart rate (HR) is an important parameter in the study of the developmental physiology of chicken embryos and a crucial indicator of dead or live embryo grading in artificial incubation processes. A non-invasive HR measurement technique is required for long-term and routine HR assessment with minimal influence on embryo development. Accordingly, in this study, a non-invasive HR measurement technique of chicken embryos using a smartphone is demonstrated. The detection method of the proposed device is based on the photoplethysmography principle in which a smartphone camera is used for video recording, and the chicken embryonic HR is obtained from the recorded video images using a custom Android application. We used a smartphone to measure the embryonic HR of 60 native chicken eggs and found that it can measure the chicken embryonic HR from day 4 to day 20. The proposed smartphone HR device will be beneficial for scientific research and industrial applications. With internet connectivity, users can utilize their smartphone to measure the HR, display, share, and store the results.

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Gangaram-Panday, Norani H., Tanja van Essen, Tom G. Goos, Rogier C. J. de Jonge, Irwin K. M. Reiss e Willem van Weteringen. "Dynamic Light Scattering: A New Noninvasive Technology for Neonatal Heart Rate Monitoring". Neonatology 117, n. 3 (2020): 279–86. http://dx.doi.org/10.1159/000506771.

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Background: Heart rate (HR) detection in premature infants using electrocardiography (ECG) is challenging due to a low signal amplitude and the fragility of the premature skin. Recently, the dynamic light scattering (DLS) technique has been miniaturized, allowing noninvasive HR measurements with a single sensor. Objective: The aim was to determine the accuracy of DLS for HR measurement in infants, compared to ECG-derived HR. Methods: Stable infants with a gestational age of ≥26 weeks, monitored with ECG, were eligible for inclusion. HR was measured with the DLS sensor at 5 different sites for 15 min each. We recorded every 10th second of the DLS-derived HR and the DLS signal-to-noise ratio (SNR), and the ECG-derived HR was extracted for analysis. Patients were randomly divided into 2 groups. In the first group, the optimal SNR cut-off value was determined and then applied to the second group to assess agreement. Results: HR measurements from 31 infants were analyzed. ECG-DLS paired data points were collected at the forehead, an upper extremity, the thorax, a lower extremity, and the abdomen. When applying the international accuracy standard for HR detection, DLS accuracy in the first group (n = 15) was optimal at the forehead (SNR cut-off 1.66). Application of this cut-off to the second group (n = 16) showed good agreement between DLS-derived HR and ECG-derived HR (bias –0.73 bpm; 95% limits of agreement –15.46 and 14.00 bpm) at the forehead with approximately 80% (i.e., 1,066/1,310) of all data pairs remaining. Conclusion: The investigated DLS sensor was sensitive to movement, overall providing less accurate HR measurements than ECG and pulse oximetry. In this study population, specific measurement sites provided excellent signal quality and good agreement with ECG-derived HR.

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Coleman, Jesse, Amy Sarah Ginsburg, William M. Macharia, Roseline Ochieng, Guohai Zhou, Dustin Dunsmuir, Walter Karlen e J. Mark Ansermino. "Identification of thresholds for accuracy comparisons of heart rate and respiratory rate in neonates". Gates Open Research 5 (10 giugno 2021): 93. http://dx.doi.org/10.12688/gatesopenres.13237.1.

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Background: Heart rate (HR) and respiratory rate (RR) can be challenging to measure accurately and reliably in neonates. The introduction of innovative, non-invasive measurement technologies suitable for resource-constrained settings is limited by the lack of appropriate clinical thresholds for accuracy comparison studies. Methods: We collected measurements of photoplethysmography-recorded HR and capnography-recorded exhaled carbon dioxide across multiple 60-second epochs (observations) in enrolled neonates admitted to the neonatal care unit at Aga Khan University Hospital in Nairobi, Kenya. Trained study nurses manually recorded HR, and the study team manually counted individual breaths from capnograms. For comparison, HR and RR also were measured using an automated signal detection algorithm. Clinical measurements were analyzed for repeatability. Results: A total of 297 epochs across 35 neonates were recorded. Manual HR showed a bias of -2.4 (-1.8%) and a spread between the 95% limits of agreement (LOA) of 40.3 (29.6%) compared to the algorithm-derived median HR. Manual RR showed a bias of -3.2 (-6.6%) and a spread between the 95% LOA of 17.9 (37.3%) compared to the algorithm-derived median RR, and a bias of -0.5 (1.1%) and a spread between the 95% LOA of 4.4 (9.1%) compared to the algorithm-derived RR count. Manual HR and RR showed repeatability of 0.6 (interquartile range (IQR) 0.5-0.7), and 0.7 (IQR 0.5-0.8), respectively. Conclusions: Appropriate clinical thresholds should be selected a priori when performing accuracy comparisons for HR and RR. Automated measurement technologies typically use median values rather than counts, which significantly impacts accuracy. A wider spread between the LOA, as much as 30%, should be considered to account for the observed physiological nuances and within- and between-neonate variability and different averaging methods. Wider adoption of thresholds by data standards organizations and technology developers and manufacturers will increase the robustness of clinical comparison studies.

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Chen, Yugang, Bomi Lee e Yong-Hwa Park. "A Helmholtz Resonator with Spiral Neck for Analyte Concentration Measurement in Low Frequency Range". Applied Sciences 10, n. 11 (26 maggio 2020): 3676. http://dx.doi.org/10.3390/app10113676.

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Helmholtz resonators (HR) have been proven to have feasibility for sensor applications with good performance. However, for biosensor application, when the amount of test sample is limited, the operating frequency tends to be very high, which may bring challenges of resonance excitation and frequency measurement. In this paper, a modified HR was proposed for biosensor application at a lower frequency, by designing the neck of the HR as a type of an Archimedes spiral, which can increase the neck length as much as possible without occupying much space. The resonant frequency of the proposed HR was derived by treating it as an HR with a straight neck with the equivalent length. An analytical example was calculated and verified by acoustic finite element analysis, and the results clearly showed that the frequency decreases in comparison to that of the conventional HR. Based on the underlying theory, the measurement principle was proposed and the experiment setup was established using a 3D-printed structure. The experiment was done using test solutions with different glucose concentrations, whose results showed consistency with the analytical results and noticeable frequency increases with the glucose concentration. Prospective results of the proposed HR after miniaturization show an operating frequency around 3 kHz when the amount of test sample is 0.1 mL, which will facilitate use of the common acoustic power source and acoustic pressure sensors in the sensing system.

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Kohlhepp, R., S. Barthlott, T. Blumenstock, F. Hase, I. Kaiser, U. Raffalski e R. Ruhnke. "Trends of HCl, ClONO 2 and HF column abundances from ground-based FTIR measurements in Kiruna (Sweden) in comparison with KASIMA model calculations". Atmospheric Chemistry and Physics Discussions 11, n. 1 (18 gennaio 2011): 1489–510. http://dx.doi.org/10.5194/acpd-11-1489-2011.

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Abstract. Trends of hydrogen chloride (HCl), chlorine nitrate (ClONO2) and hydrogen fluoride (HF) column abundances above Kiruna (Northern Sweden, 67.84° N, 20.41° E) derived from nearly 14 years (1996–2009) of measurement and model data are presented. The measurements have been performed with a Bruker 120 HR (later Bruker 125 HR) Fourier transform infrared (FTIR) spectrometer and the model used was KASIMA (KArlsruhe SImulation model of the Middle Atmosphere). To calculate the long-term trends, a linear function combined with an annual cycle was fitted to the data using a least squares method. The precision of the resulting trends was estimated with the so-called bootstrap resampling method. The relative trends were calculated on the basis of the linear fit result on 1 January 2000, 12:00 UTC. For hydrogen fluoride, both model and measurements show a positive trend that seems to decrease in the last few years. This suggests a stabilisation of the HF total column abundance. For the summer data (August to November), the FTIR trend of (+1.25 ± 0.28)%/yr agrees within errors with the KASIMA one of (+1.55 ± 0.11)%/yr. The trends determined for HCl and ClONO2 are significantly negative over the time period considered here. This corresponds to the expectations because the emission of their precursors (chlorofluorocarbons and hydrochlorofluorocarbons) has been restricted in the Montreal Protocol in 1987 and its amendments and adjustments. The relative trend for ClONO2 from the FTIR measurements amounts to (−3.28 ± 0.56)%/yr and the one for HCl to (−0.81± 0.23)%/yr. KASIMA simulates a weaker decrease: For ClONO2, the result is (−0.90 ± 0.10)%/yr and for HCl (−0.17± 0.06)%/yr. Part of the difference between measurement and model data can be explained by sampling and the stronger annual cycle indicated by the measurements. There is a factor of about four between the trends of HCl and ClONO2 above Kiruna for both measurement and model data. The absolute values of ClONO2 and HF calculated by KASIMA agree quite well with the FTIR measurements while KASIMA tends to underestimate the HCl column abundances.

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Kohlhepp, R., S. Barthlott, T. Blumenstock, F. Hase, I. Kaiser, U. Raffalski e R. Ruhnke. "Trends of HCl, ClONO2, and HF column abundances from ground-based FTIR measurements in Kiruna (Sweden) in comparison with KASIMA model calculations". Atmospheric Chemistry and Physics 11, n. 10 (18 maggio 2011): 4669–77. http://dx.doi.org/10.5194/acp-11-4669-2011.

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Abstract. Trends of hydrogen chloride (HCl), chlorine nitrate (ClONO2), and hydrogen fluoride (HF) total column abundances above Kiruna (Northern Sweden, 67.84° N, 20.41° E) derived from nearly 14 years (1996–2009) of measurement and model data are presented. The measurements have been performed with a Bruker 120 HR (later Bruker 125 HR) Fourier transform infrared (FTIR) spectrometer and the chemistry-transport model (CTM) used was KASIMA (KArlsruhe SImulation model of the Middle Atmosphere). The total column abundances of ClONO2 and HF calculated by KASIMA agree quite well with the FTIR measurements while KASIMA tends to underestimate the HCl columns. To calculate the long-term trends, a linear function combined with an annual cycle was fitted to the data using a least squares method. The precision of the resulting trends was estimated with the bootstrap resampling method. For HF, both model and measurements show a positive trend that seems to decrease in the last few years. This suggests a stabilisation of the HF total column abundance. Between 1996 and 2009, KASIMA simulates an increase of (+1.51±0.07) %/yr which exceeds the FTIR result of (+0.65±0.25) %/yr. The trends determined for HCl and ClONO2 are significantly negative over the time period considered here. This is expected because the emission of their precursors (chlorofluorocarbons and hydrochlorofluorocarbons) has been restricted in the Montreal Protocol in 1987 and its amendments and adjustments. The trend for ClONO2 from the FTIR measurements amounts to (−3.28±0.56) %/yr and the one for HCl to (−0.81±0.23) %/yr. KASIMA simulates a weaker decrease: For ClONO2, the result is (−0.90±0.10) %/yr and for HCl (−0.17±0.06) %/yr. Part of the difference between measurement and model data can be explained by sampling and the stronger annual cycle indicated by the measurements. There is a factor of about four between the trends of HCl and ClONO2 above Kiruna for both measurement and model data.

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Bagchi, Aditi, Zachary Madaj, Kelly B. Engel, Ping Guan, Daniel C. Rohrer, Dana R. Valley, Emily Wolfrum et al. "Impact of Preanalytical Factors on the Measurement of Tumor Tissue Biomarkers Using Immunohistochemistry". Journal of Histochemistry & Cytochemistry 69, n. 5 (1 marzo 2021): 297–320. http://dx.doi.org/10.1369/0022155421995600.

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Analysis of formalin-fixed paraffin-embedded (FFPE) tissue by immunohistochemistry (IHC) is commonplace in clinical and research laboratories. However, reports suggest that IHC results can be compromised by biospecimen preanalytical factors. The National Cancer Institute’s Biospecimen Preanalytical Variables Program conducted a systematic study to examine the potential effects of delay to fixation (DTF) and time in fixative (TIF) on IHC using 24 cancer biomarkers. Differences in IHC staining, relative to controls with a DTF of 1 hr, were observed in FFPE kidney tumor specimens after a DTF of ≥2 hr. Reductions in H-score and/or staining intensity were observed for c-MET, p53, PAX2, PAX8, pAKT, and survivin, whereas increases were observed for RCC1, EGFR, and CD10. Prolonged TIF of 72 hr resulted in significantly reduced H-scores of CD44 and c-Met in kidney tumor specimens, compared with controls with 12-hr TIF. An elevated probability of altered staining intensity due to DTF was observed for nine antigens, whereas for prolonged TIF an elevated probability was observed for one antigen. Results reported here and elsewhere across tumor types and antigens support limiting DTF to ≤1 hr when possible and fixing tissues in formalin for 12–24 hr to avoid confounding effects of these preanalytical factors on IHC.

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Shapiro, Daniel D., Jose A. Karam, Philippe E. Spiess, Jay D. Raman, Mary E. Westerman, Wade J. Sexton, Logan Zemp et al. "Preoperative metastatic disease burden to predict overall survival following cytoreductive nephrectomy independent of IMDC risk category." Journal of Clinical Oncology 38, n. 6_suppl (20 febbraio 2020): 652. http://dx.doi.org/10.1200/jco.2020.38.6_suppl.652.

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652 Background: Studies suggest that overall survival (OS) following cytoreductive nephrectomy (CN) is associated with preoperative tumor measurements including primary tumor diameter, number of metastatic sites, sum of metastatic tumor diameters and primary tumor percent of overall burden. Current risk models, however, do not account for tumor burden. This study evaluated associations between OS and preoperative tumor measurements for patients treated with CN during the targeted therapy era. Methods: Data for consecutive mRCC patients treated with CN at 4 institutions from 2006-2017 were analyzed after determining IMDC risk category, primary tumor (PT) diameter, number of metastatic sites, sum of metastatic tumor diameters and PT percentage of overall burden. Univariate and multivariable (MV) Cox models evaluated tumor measurement and IMDC risk associations with OS. Results: A total of 617 patients were available for analysis. Median PT diameter was 10.0 cm (IQR 7-13cm), number of metastatic sites was 2 (IQR 1-2), sum of metastatic tumor diameters was 4.5 cm (IQR 2-10cm) and PT percent of overall burden was 73.7% (IQR 60-85%). After univariate analysis, all 4 tumor burden measures were associated with OS (p≤0.001 for all). MV models evaluating IMDC risk category with individual tumor burden measurements demonstrated that all measures were predictive as continuous variables: PT diameter (HR 1.03, 95% CI 1.01-1.06, p=0.007), sum of metastatic tumor diameters (HR 1.04, 95% CI 1.02-1.05, p<0.001), PT percent of overall burden (HR 0.43, 95% CI 0.27-0.68, p<0.001), and number of metastatic sites (HR 1.52, 95% CI 1.25-1.85, p<0.001). Additional MV models were created using clinically significant tumor measurement cutoffs and IMDC risk groups. OS was independently associated with IMDC intermediate (HR 3.17, 95% CI 1.84-5.44, p<0.001) and poor risk (HR 3.85, 95% CI 2.21-6.70, p<0.001), PT percentage of overall burden <90% (HR 1.41, 95% CI 1.05-1.89, p=0.021), and >2 metastatic sites (HR 1.60, 95% CI 1.29-2.00, p<0.001). Conclusions: PT and metastatic disease burden are independently associated with OS following CN. Future risk models should include tumor burden measurements.

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Hahnen, Christina, Cecilia G. Freeman, Nilanjan Haldar, Jacquelyn N. Hamati, Dylan M. Bard, Vignesh Murali, Geno J. Merli, Jeffrey I. Joseph e Noud van Helmond. "Accuracy of Vital Signs Measurements by a Smartwatch and a Portable Health Device: Validation Study". JMIR mHealth and uHealth 8, n. 2 (12 febbraio 2020): e16811. http://dx.doi.org/10.2196/16811.

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Background New consumer health devices are being developed to easily monitor multiple physiological parameters on a regular basis. Many of these vital sign measurement devices have yet to be formally studied in a clinical setting but have already spread widely throughout the consumer market. Objective The aim of this study was to investigate the accuracy and precision of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and oxygen saturation (SpO2) measurements of 2 novel all-in-one monitoring devices, the BodiMetrics Performance Monitor and the Everlast smartwatch. Methods We enrolled 127 patients (>18 years) from the Thomas Jefferson University Hospital Preadmission Testing Center. SBP and HR were measured by both investigational devices. In addition, the Everlast watch was utilized to measure DBP, and the BodiMetrics Performance Monitor was utilized to measure SpO2. After 5 min of quiet sitting, four hospital-grade standard and three investigational vital sign measurements were taken, with 60 seconds in between each measurement. The reference vital sign measurements were calculated by determining the average of the two standard measurements that bounded each investigational measurement. Using this method, we determined three comparison pairs for each investigational device in each subject. After excluding data from 42 individuals because of excessive variation in sequential standard measurements per prespecified dropping rules, data from 85 subjects were used for final analysis. Results Of 85 participants, 36 (42%) were women, and the mean age was 53 (SD 21) years. The accuracy guidelines were only met for the HR measurements in both devices. SBP measurements deviated 16.9 (SD 13.5) mm Hg and 5.3 (SD 4.7) mm Hg from the reference values for the Everlast and BodiMetrics devices, respectively. The mean absolute difference in DBP measurements for the Everlast smartwatch was 8.3 (SD 6.1) mm Hg. The mean absolute difference between BodiMetrics and reference SpO2 measurements was 3.02%. Conclusions Both devices we investigated met accuracy guidelines for HR measurements, but they failed to meet the predefined accuracy guidelines for other vital sign measurements. Continued sale of consumer physiological monitors without prior validation and approval procedures is a public health concern.

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Frese, Ethel M., Randy R. Richter e Tamara V. Burlis. "Self-Reported Measurement of Heart Rate and Blood Pressure in Patients by Physical Therapy Clinical Instructors". Physical Therapy 82, n. 12 (1 dicembre 2002): 1192–200. http://dx.doi.org/10.1093/ptj/82.12.1192.

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Abstract Background and Purpose. The Guide to Physical Therapist Practice (Guide) recommends that heart rate (HR) and blood pressure (BP) measurement be included in the examination of new patients. The purpose of this study was to survey physical therapy clinical instructors to determine the frequency of HR and BP measurement in new patients and in patients already on the physical therapists' caseload. The use of information obtained from HR and BP measures in decision making for patient care and the effects of practice setting and academic preparation on the measurement and use of HR and BP also were examined. Subjects and Methods. A sample of 597 subjects was selected from a list of 2,663 clinical instructors at the clinical education sites of the 2 participating universities. Clinical instructors from a variety of practice settings were surveyed. A 26-item survey questionnaire was mailed to the clinical instructors. Results. Usable survey questionnaires were received from 387 respondents (64.8%); 43.4% reported working in an outpatient facility. The majority of the respondents strongly agreed or agreed (59.5%) that measurement of HR and BP should be included in physical therapy screening. When asked if routinely measuring HR and BP during clinical practice is essential, opinions were nearly split (strongly agree or agree=45.0%, strongly disagree or disagree=43.7%, no opinion=11.3%). More than one third (38.0%) of the respondents reported never measuring HR in the week before the survey as part of their examination of new patients. A slightly larger percentage (43.0%) reported never measuring BP of new patients in the week before the survey. Conversely, 6.0% and 4.4% of the respondents reported always measuring HR and BP, respectively, of new patients in the week before the survey. When given a list of reasons why HR and BP were not routinely measured in their clinical practice, respondents most frequently chose “not important for my patient population” (52.3%). Relationships were found between practice setting and frequency of HR and BP measurement in new patients. Discussion and Conclusion. Practices related to HR and BP measurement reported by this sample of clinical instructors do not meet the recommendations for physical therapy care described in the Guide.

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Sutejo, Raih, e Siti Daryati. "Pengukuran Laju Paparan Radiasi pada Perisai Radiasi Ruang Panoramik di Instalasi Radiologi Rumah Sakit Islam Klaten". Jurnal Imejing Diagnostik (JImeD) 2, n. 2 (11 luglio 2016): 164–66. http://dx.doi.org/10.31983/jimed.v2i2.3177.

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Background: Research about the measurement of radiation exposure rate on panoramic radiation shield in Radiology Installation of Klaten Islamic Hospital has been conducted. The background of this research is in the panoramic room there is a veil that has a gap on the bottom as high as 20 cm. The purpose of this research is to know the rate of radiation exposure on radiation panoramic shield in Radiology Installation of Klaten Islamic Hospital and the application of radiation protection system to the room.Methods: This research type is quantitative with survey approach that is writer do observation, documentation and measurement of exposure rate of radiation at controlled and uncontrolled area by doing measurement at two state that is before exposure (background radiation) and after exposure. The data obtained are then analyzed descriptively to declare a safe examination room or not for workers and the general public by comparing the measurement results with UNSCEAR and NCRP report No. 147.Result: The value of the background exposure rate in the panoramic chamber of the Klaten Hospital Radiology Installation exceeds the value of the background dose rate based on the location of the height of an area according to UNSCEAR. The background exposure value in the panoramic space ranges from 0.14 to 0.175 μGy/hour. The actual radiation exposure measurements at point A is 0.00021 mGy/hour, point B is 0.000175 mGy/h, point C is 0 mGy/hour, point D is 0 mGy/hour, point E is 0.000105 mGy/hour, point G is 0,000735 mGy/hour. These six results have not exceeded the NCRP report no. 147 is for controlled areas 0.0025 mGy / hr and uncontrolled area 0.0005 mGy / hr.

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Zhang, Tiantian, Jun Jiang, Ben Britton, Barbara Shollock e Fionn Dunne. "Crack nucleation using combined crystal plasticity modelling, high-resolution digital image correlation and high-resolution electron backscatter diffraction in a superalloy containing non-metallic inclusions under fatigue". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 472, n. 2189 (maggio 2016): 20150792. http://dx.doi.org/10.1098/rspa.2015.0792.

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A crystal plasticity finite-element model, which explicitly and directly represents the complex microstructures of a non-metallic agglomerate inclusion within polycrystal nickel alloy, has been developed to study the mechanistic basis of fatigue crack nucleation. The methodology is to use the crystal plasticity model in conjunction with direct measurement at the microscale using high (angular) resolution-electron backscatter diffraction (HR-EBSD) and high (spatial) resolution-digital image correlation (HR-DIC) strain measurement techniques. Experimentally, this sample has been subjected to heat treatment leading to the establishment of residual (elastic) strains local to the agglomerate and subsequently loaded under conditions of low cyclic fatigue. The full thermal and mechanical loading history was reproduced within the model. HR-EBSD and HR-DIC elastic and total strain measurements demonstrate qualitative and quantitative agreement with crystal plasticity results. Crack nucleation by interfacial decohesion at the nickel matrix/agglomerate inclusion boundaries is observed experimentally, and systematic modelling studies enable the mechanistic basis of the nucleation to be established. A number of fatigue crack nucleation indicators are also assessed against the experimental results. Decohesion was found to be driven by interface tensile normal stress alone, and the interfacial strength was determined to be in the range of 1270–1480 MPa.

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Fu, Congsheng, Guiling Wang, Michael L. Goulden, Russell L. Scott, Kenneth Bible e Zoe G. Cardon. "Combined measurement and modeling of the hydrological impact of hydraulic redistribution using CLM4.5 at eight AmeriFlux sites". Hydrology and Earth System Sciences 20, n. 5 (17 maggio 2016): 2001–18. http://dx.doi.org/10.5194/hess-20-2001-2016.

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Abstract. Effects of hydraulic redistribution (HR) on hydrological, biogeochemical, and ecological processes have been demonstrated in the field, but the current generation of standard earth system models does not include a representation of HR. Though recent studies have examined the effect of incorporating HR into land surface models, few (if any) have done cross-site comparisons for contrasting climate regimes and multiple vegetation types via the integration of measurement and modeling. Here, we incorporated the HR scheme of Ryel et al. (2002) into the NCAR Community Land Model Version 4.5 (CLM4.5), and examined the ability of the resulting hybrid model to capture the magnitude of HR flux and/or soil moisture dynamics from which HR can be directly inferred, to assess the impact of HR on land surface water and energy budgets, and to explore how the impact may depend on climate regimes and vegetation conditions. Eight AmeriFlux sites with contrasting climate regimes and multiple vegetation types were studied, including the Wind River Crane site in Washington State, the Santa Rita Mesquite savanna site in southern Arizona, and six sites along the Southern California Climate Gradient. HR flux, evapotranspiration (ET), and soil moisture were properly simulated in the present study, even in the face of various uncertainties. Our cross-ecosystem comparison showed that the timing, magnitude, and direction (upward or downward) of HR vary across ecosystems, and incorporation of HR into CLM4.5 improved the model-measurement matches of evapotranspiration, Bowen ratio, and soil moisture particularly during dry seasons. Our results also reveal that HR has important hydrological impact in ecosystems that have a pronounced dry season but are not overall so dry that sparse vegetation and very low soil moisture limit HR.

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Zhang, Boyuan, Hengkang Li, Lisheng Xu, Lin Qi, Yudong Yao e Stephen E. Greenwald. "Noncontact Heart Rate Measurement Using a Webcam, Based on Joint Blind Source Separation and a Skin Reflection Model: For a Wide Range of Imaging Conditions". Journal of Sensors 2021 (13 luglio 2021): 1–18. http://dx.doi.org/10.1155/2021/9995871.

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Remote photoplethysmography (rPPG) can be used for noncontact and continuous measurement of the heart rate (HR). Currently, the main factors affecting the accuracy and robustness of rPPG-based HR measurement methods are the subject’s skin tone, body movement, exercise recovery, and variable or inadequate illumination. In response to these challenges, this study is aimed at investigating a rPPG-based HR measurement method that is effective under a wide range of conditions by only using a webcam. We propose a new approach, which combines joint blind source separation (JBSS) and a projection process based on a skin reflection model, so as to eliminate the interference of background illumination and enhance the extraction of pulse rate information. Three datasets derived from subjects with different skin tones considering six environmental scenarios are used to validate the proposed method against three other state-of-the-art methods. The results show that the proposed method can provide more accurate and robust HR measurement for all three datasets and is therefore more applicable to a wide range of scenarios.

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Wickremasinghe, Andrea C., Brad S. Karon e Walter J. Cook. "Accuracy of Neonatal Transcutaneous Bilirubin Measurement in the Outpatient Setting". Clinical Pediatrics 50, n. 12 (18 ottobre 2011): 1144–49. http://dx.doi.org/10.1177/0009922811417292.

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Objective. To evaluate the effectiveness of transcutaneous bilirubin (TcB) measurement in predicting risk for neonatal hyperbilirubinemia in outpatients. Design. Subjects were infants ≤8 days old seen in an outpatient clinic. Infants discharged with high-risk (HR) or high-intermediate risk (HIR) total serum bilirubin (TSB) values and jaundiced infants were recruited. TSB and TcB (BiliChek) levels were plotted on an hour-specific nomogram to determine risk for hyperbilirubinemia. Results. A total of 79 infants provided 87 sets of TcB and TsB values. Mean bias and standard deviation between TcB and TsB was 1.5 ± 2.1 mg/dL for outpatients, compared with 2.7 ± 1.3 mg/dL for inpatients. The sensitivity and specificity of HR or HIR TcB for predicting an HR or HIR TSB were 87% and 58%, respectively. Of 9 infants readmitted for phototherapy, 1 had a low-risk TcB and high-risk TSB. Conclusions. TcB screening in the outpatient environment may not be safe and efficient.

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Sanner, Jennifer E., Lorraine Frazier e Malini Udtha. "Effects of Delayed Laboratory Processing on Platelet Serotonin Levels". Biological Research For Nursing 15, n. 1 (22 agosto 2011): 13–16. http://dx.doi.org/10.1177/1099800411416636.

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Background: Despite the availability of established guidelines for measuring platelet serotonin, these guidelines may be difficult to follow in a hospital setting where time to processing may vary from sample to sample. Purpose: The purpose of this study was to evaluate the effect of the time to processing of human blood samples on the stability of the enzyme-linked immunosorbent assay (ELISA) for the determination of platelet serotonin levels in human plasma. Method: Human blood samples collected from a convenience sample of eight healthy volunteers were analyzed to determine platelet serotonin levels from plasma collected in ethylene diamine tetra acetic acid (EDTA) tubes and stored at 4°C for 3 hr, 5 hr, 8 hr, and 12 hr. Results: Refrigeration storage at 4°C for 3 hr, 5 hr, 8 hr, and 12 hr altered the platelet serotonin measurement when compared to immediate processing. The bias for the samples stored at 4°C for 3 hr was 102.3 (±217.39 ng/109 platelets), for 5 hr was 200.1 (±132.76 ng/109 platelets), for 8 hr was 146.9 (±221.41 ng/109 platelets), and for 12 hr was −67.6 (±349.60 ng/109 platelets). Discussion: Results from this study show that accurate measurement of platelet serotonin levels is dependent on time to processing. Researchers should therefore follow a standardized laboratory guideline for obtaining immediate platelet serotonin levels after blood sample collection.

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Jacobi, Nicole, Regine Grosse, Tugce Aktas, Lena Herich, Peter Nielsen, Roland Fischer, Tatjana Zabelina, Ulrike Bacher e Nicolaus Kroeger. "Measurement of Liver Iron Concentration by Quantum Interference Device Biosusceptometry (SQUID) Validates Serum Ferritin As Prognostic Parameter for Allogeneic Stem Cell Transplantation". Blood 118, n. 21 (18 novembre 2011): 1018. http://dx.doi.org/10.1182/blood.v118.21.1018.1018.

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Abstract Abstract 1018 Introduction: There is conflicting data regarding the role of serum ferritin (SF) as an independent prognostic factor for outcome after allogeneic stem cell transplantation (allo-SCT). SF is a surrogate parameter for iron overload and - as an acute phase-protein - can be confounded by many factors. An independent, non-invasive measurement of iron overload is needed. Determining iron content through SQUID correlates well with results of liver biopsies (Nielsen et al. 1998). This method measures the interference of an exteriorly applied small but highly constant magnetic field by the paramagnetic liver storage iron of the patient. Methods: We conducted a single-center retrospective analysis from October 1994 to December 2012, comparing the effect of SF and liver iron content measured by SQUID shortly before transplantation on overall survival (OS), event-free survival (EFS) and transplant-related mortality (TRM) in 143 patients (median age 40 years) undergoing allo-SCT (73% reduced intensity regimen). The diagnoses were subdivided into 4 groups: myelodysplastic syndrome, secondary acute myeloid leukemia (AML), primary myelofibrosis, primary AML and other. Statistical calculations employed Pearson's correlation, ordinal logistic regression, Cox regression analysis and multiple Cox regression analyses with backward elimination. Results: Correlation between SF and SQUID showed a highly significant result of r=0.5 (p < 0.001). The chance of infection was increased 2.4-fold (CI 1.22,4.71) when SQUID values ranged > 1000 μg Fe/g liver. We found similar results for SF > 1000 ng/ml (p 0.003), where the risk of infection was increased 2.87–fold (CI 1.43;5.78). A significant association between SQUID und fungal infection was also seen (p 0.004). For patients with SQUID > 1000 the chance of proven fungal infection versus fungal infection of all other categories was increased 3.08-fold (CI 1.43,6.63). Similarly an association between SF > 1000 and fungal infection could be demonstrated (p 0.001), with a 4.04-fold increased chance of proven fungal infection versus lower fungus categories for patients with SF values > 1000. There was no association between continuous SQUID-, respectively SF values and VOD (veno-occlusive disease) or acute GvHD. The following variables were significantly related with OS: chronic GvHD (HR 0.326, CI 0.13–0.83, p 0.019,), sepsis (p 0.002, HR 2.94 CI 1.48–5.83), new onset cardiac abnormalities (p 0.001, HR 3.21, CI 1.64–6.27), SF > 1000 (p 0.033, HR 2.09, CI 1.06–4.11). For EFS we found statistically significant results for chronic GvHD (p 0.040, HR 0.45, CI 0.21–0.97), sepsis (p 0.012, HR 2.35, CI 1.21–4.58), cardiac abnormalities (p 0.001, HR 2.81, CI 1.50–5.29), SF > 1000 (p 0.016, HR 2.15, CI 1.15–4.10) and time to engraftment (p 0.038, HR 0.934, CI 0.89–1.00). For TRM, statistically significant results were found for sepsis (p 0.005, HR 3.23, CI 1.43–7.29), cardiac abnormalities (p < 0.001, HR 5.21, CI 2.41–11.27), and age (p 0.034, HR 1.04, CI 1.00–1.08). Fungal infection of all categories was not statistically significant (p=1,101), but proven fungal infection in comparison with no fungal infection was found significant (p 0.018, HR 3.12, CI 1.22–7.99. In the multivariate analysis SF and SQUID (categorical and continuous) were not significant factors for OS, EFS or TRM. Conclusion: Our data confirmed previous publications that SF > 1000 increases the risk of infection, moreover fungal infection. In the univariate analysis it is significantly associated with OS and EFS during allo-SCT. As SQUID values correlate well with SF, we could show that SF is indeed a good surrogate parameter for iron overload when measured shortly before allo-SCT. We are now in need of prospective trials investigating the effect of iron chelation before or during allo-SCT on transplant outcome. Disclosures: No relevant conflicts of interest to declare.

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Rosa, Nicola, Maddalena De Bernardo, Angela Pepe, Livio Vitiello, Giuseppe Marotta, Roberto Imparato e Luigi Capasso. "Corneal thickness evaluation in healthy eyes: Comparison between two different Scheimpflug devices". PLOS ONE 15, n. 12 (3 dicembre 2020): e0243370. http://dx.doi.org/10.1371/journal.pone.0243370.

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Purpose To evaluate the correlation between corneal thickness (CT) measurements obtained with two Scheimpflug devices, Pentacam HR and Precisio, and to elaborate, if necessary, a regression formula which could make these results comparable. Design Retrospective, Comparative, Observational study. Setting Department of Medicine, Surgery and Dentistry, “Scuola Medica Salernitana” University of Salerno, Italy Methods One hundred twenty four healthy eyes of 124 volunteers (65 males; range: 20–32 years; mean age of 24.8 ± 1.7) were included in this study. CT was measured using Pentacam HR and Precisio in three different points: the pupil center (PC), the corneal apex (CA) and the thinnest point (TP). Results CT obtained with both devices at the PC, at the CA and at the TP showed a good correlation (r = 0.97, r = 0.97, r = 0.97, respectively), but Pentacam HR measurements were significantly thicker than those provided by Precisio (p < 0.01). The differences between Pentacam HR and Precisio were 21.9 ± 8.8 μm at the PC, 21.9 ± 8.9 μm at the CA, 19.1 ± 9.0 μm at the TP. The calculated regression formulas were: y = 0.9558x + 2.3196 for the PC, y = 0.9519x + 4.5626 for the CA, y = 0.9364x + 15.436 for the TP, where x is the CT measured with Pentacam HR and y is the Precisio measurement. Conclusions The findings provided by this study highlight that Precisio measures thinner corneas compared to Pentacam HR. The identified regression formulas could be utilized to make interchangeable the results obtained with these two devices.

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Tyovenda, A. A., A. A. Akombor e S. T. Tamaugee. "Measurement of Environmental Radioactivity within Dangote Cement Escavation Site Gboko, Benue State." NIGERIAN ANNALS OF PURE AND APPLIED SCIENCES 6 (28 dicembre 2015): 168–72. http://dx.doi.org/10.46912/napas.23.

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The radioactivity of rocks from Dangote Cement excavation site in Gboko, Benue State were monitored and measured using the radiation meter inspector 06250 and dose meter 6150AD 2/4/6. The meters measure the dose rate, exposure rate and the activity. The meters were held 1 meter above the surface of the soil at the excavation site. Each reading was taken 10 times at varying distances between zero and 100 meters from the excavation site after which the mean readings for each of the distance were then found. Finally, the background count was taken 200 meters away from the excavation point. The highest value of dose equivalent rate of 0.428±0.006 mSv/yr, exposure rate of 0.206±0.003 mR/hr and activity of 6.8±0.4kBq were measured at zero distance from the excavation point while the least value of dose equivalent rate of 0.212±0.002 mSv/yr, exposure rate of 0.081±0.001 mR/hr and activity of 3.2±0.8kBq were obtained at 100 meters away from the excavation point. The result shows that the excavation site is within the safety limit set by the international commission on Radiological protection (ICRP) (1990).

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Al-Naji, Ali, e Javaan Chahl. "Noncontact Heart Activity Measurement System Based on Video Imaging Analysis". International Journal of Pattern Recognition and Artificial Intelligence 31, n. 02 (12 gennaio 2017): 1757001. http://dx.doi.org/10.1142/s0218001417570014.

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Vital parameter monitoring systems based on video camera imagery is a growing interest field in clinical and biomedical applications. Heart rate (HR) is one of the most important vital parameters of interest in a clinical diagnostic and monitoring system. This study proposed a noncontact HR and beat length measurement system based on both motion magnification and motion detection at four different regions of interest (ROIs) (wrist, arm, neck and leg). A motion magnification based on a Chebyshev filter was utilized in order to magnify heart pulses in different ROIs that are difficult to see with the naked eye. A new measuring system based on motion detection was used to measure HR and beat length by detecting rapid motion areas in the video frame sequences that represent the heart pulses and converting video frames into a corresponding logical matrix. Video quality metrics were also used to compare our magnification system with standard Eulerian video magnification to select which one has better magnification results and gives better results for the heart pulse. The 99.3% limits of agreement between the proposed system and reference measurement fall within[Formula: see text] beats/min based on Bland and Altman test. The proposed system is expected to produce new options for further noncontact information extraction.

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Stock, Joseph M., Ryan T. Pohlig, Matthew J. Botieri, David G. Edwards e Gregory M. Dominick. "Heart Rate Equivalency of the Fitbit Charge HR During Continuous Aerobic Exercise". Journal for the Measurement of Physical Behaviour 1, n. 3 (1 settembre 2018): 122–29. http://dx.doi.org/10.1123/jmpb.2018-0009.

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Purpose: Consumer-grade wrist-worn activity monitors frequently include photoplethysmography (PPG) sensors for estimating heart rate (HR). The Fitbit Charge HR is marketed specifically for tracking fitness; therefore, HR accuracy is critical, especially during exercise. This study examined HR equivalency of the Fitbit Charge HR during continuous aerobic exercise. Method: Participants (N = 19) concurrently wore a Polar H1 and Fitbit Charge HR during a measurement visit that included seated rest (5 minutes), warm-up (5 minutes), continuous treadmill exercise (30 minutes), and cool-down (5–10 minutes). Mean HR differences were examined by protocol phase, total activity (i.e., warm-up, exercise, and cool-down combined), and the first, middle, and last 5 minutes of continuous exercise. Mean absolute percent error (MAPE), Bland-Altman plots, and 95% equivalence testing explained overall and individual HR agreement between devices. Results: The Fitbit Charge HR significantly underestimated HR for all measurement phases (all p ≤ .01) except cool-down (p > .33). HR agreement was notably weaker during warm-up (r = 0.66, d = 0.57) and differences were greatest for the first 5 minutes compared to the middle and end of exercise (6.94±2.16 beats per minute [bpm] vs. 1.76±0.59 bpm, and 1.74±0.58 bpm), F = 4.87, p = .04). Mean exercise HRs were equivalent between devices (±2.69 bpm, 95% CI: 1.41–3.97 bpm); MAPE was 1.96%. Conclusion: The Fitbit Charge HR is relatively accurate for measuring HR during continuous aerobic exercise. Whereas the accuracy of PPG-based HR appears limited at exercise onset, agreement improves throughout the exercise bout and HR differences are negligible.

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Nedoma, Jan, Stanislav Kepak, Marcel Fajkus, Jakub Cubik, Petr Siska, Radek Martinek e Petr Krupa. "Magnetic Resonance Imaging Compatible Non-Invasive Fibre-Optic Sensors Based on the Bragg Gratings and Interferometers in the Application of Monitoring Heart and Respiration Rate of the Human Body: A Comparative Study". Sensors 18, n. 11 (31 ottobre 2018): 3713. http://dx.doi.org/10.3390/s18113713.

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The publication presents a comparative study of two fibre-optic sensors in the application of heart rate (HR) and respiratory rate (RR) monitoring of the human body. After consultation with clinical practitioners, two types of non-invasive measuring and analysis systems based on fibre Bragg grating (FBG) and fibre-optic interferometer (FOI) have been designed and assembled. These systems use probes (both patent pending) that have been encapsulated in the bio-compatible polydimethylsiloxane (PMDS). The main advantage of PDMS is that it is electrically non-conductive and, as well as optical fibres, has low permeability. The initial verification measurement of the system designed was performed on four subjects in a harsh magnetic resonance (MR) environment under the supervision of a senior radiology assistant. A follow-up comparative study was conducted, upon a consent of twenty volunteers, in a laboratory environment with a minimum motion load and discussed with a head doctor of the Radiodiagnostic Institute. The goal of the laboratory study was to perform measurements that would simulate as closely as possible the environment of harsh MR or the environment of long-term health care facilities, hospitals and clinics. Conventional HR and RR measurement systems based on ECG measurements and changes in the thoracic circumference were used as references. The data acquired was compared by the objective Bland–Altman (B–A) method and discussed with practitioners. The results obtained confirmed the functionality of the designed probes, both in the case of RR and HR measurements (for both types of B–A, more than 95% of the values lie within the ±1.96 SD range), while demonstrating higher accuracy of the interferometric probe (in case of the RR determination, 95.66% for the FOI probe and 95.53% for the FBG probe, in case of the HR determination, 96.22% for the FOI probe and 95.23% for the FBG probe).

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Briot, Danielle, e Noel Robichon. "Hipparcos Positions of B/Be Stars on the HR Diagram". International Astronomical Union Colloquium 175 (2000): 117–28. http://dx.doi.org/10.1017/s0252921100055731.

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AbstractAbsolute magnitudes of Be and B stars are computed for each spectral type and luminosity class V and IV, using the Hipparcos parallax measurements. Some simulations have been carried out in order to estimate the effects which could bias the mean absolute magnitude calculations. As a result, only stars with σπ/π < 15% have been used. A first result is that B stars are fainter than previous estimations by about 0.5 magnitude on average. We then observe that on average Be stars are brighter than B stars of the same spectral type and this over-luminosity increases with the spectral type. A possible interpretation is proposed based on the fact that the rotational velocity of the late Be stars is near the critical rotational velocity.

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Łysiak, Grzegorz. "Measurement of ethylene production as a method for determining the optimum harvest date of ‘Jonagored’ apples". Folia Horticulturae 26, n. 2 (1 dicembre 2014): 117–24. http://dx.doi.org/10.1515/fhort-2015-0002.

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ABSTRACT The measurement of ethylene concentration in the apple core is considered a good method of determining OHD, but requires high accuracy and expensive equipment. The measurement of ethylene production seems to be a technologically easier method. During research conducted in the years 2003-2008, measurements of ethylene production were evaluated as a method for determining the harvest maturity of ‘Jonagored’ apples intended for storage. Measurements were carried out every 4-5 days starting a few weeks before the estimated harvest date. Apples were picked on four dates and after five months the loss of mass, firmness, TSS and TA was measured, the incidence of physiological disorders and fungal diseases was assessed and sensory tests were conducted to evaluate storability. Based on this evaluation it was determined which of those dates was OHD. After a period of low ethylene production, the production accelerated rapidly to reach an average level between 10.0 and 12.5 ppm kg-1 hr-1 on the OHD. Later, ethylene production rose still more sharply and quickly reached several dozens of ppm kg-1 hr-1. The accuracy of the new method was compared with other methods used to determine the maturity stage. The results obtained through the measurement of ethylene production showed the least deviation from the six-year average and only the results obtained using the Streif index method, which may be unreliable for some cultivars according to the literature, had a comparable margin of error.

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Horstman, Erik, Thorsten Balke, Tjeerd Bouma, Marjolein Dohmen-Janssen e Suzanne Hulscher. "OPTIMIZING METHODS TO MEASURE HYDRODYNAMICS IN COASTAL WETLANDS: EVALUATING THE USE AND POSITIONING OF ADV, ADCP AND HR-ADCP". Coastal Engineering Proceedings 1, n. 32 (31 gennaio 2011): 51. http://dx.doi.org/10.9753/icce.v32.waves.51.

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Abstract (sommario):

Hydrodynamic impacts of vegetation in the intertidal zone are highly important to coastal protection. However, most studies on hydrodynamic impacts of vegetation in the intertidal zone are carried out in flumes. This results in a lack of field data for validating models that describe short-term hydrodynamic impacts of vegetation. The current research focuses on field measurements of flow patterns and waves in vegetated intertidal areas. Ample measurement devices are available to measure hydrodynamic processes in the field. Examples are: acoustic Doppler current profilers (ADCP), high resolution acoustic Doppler current profilers (HR-ADCP) and acoustic Doppler velocity meters (ADV). This study focuses on the differences in the performance of these devices, to determine which of them can be best deployed in a future fieldwork campaign in mangroves. Major points of attention in this comparison are the accuracy of the data and the potential disturbance of the measurements by the presence of vegetation. It is concluded that ADV’s perform very well in vegetated intertidal areas, while (HR-)ADCP’s show difficulties when deployed upward looking. Furthermore, ADV’s are preferred over (HR-)ADCP’s due to their ability of combining high frequent wave and current measurements and their convenient deployment.

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Gallivan, Monica V., Laura A. Worfolk, Christina D. Lapuz, Olivia Saqui, Larielyn P. Pan e Jeffrey S. Dlott. "Comparison of High Resolution HPLC with Capillary Zone Electrophoresis in Hemoglobin A2 Measurement." Blood 110, n. 11 (16 novembre 2007): 3832. http://dx.doi.org/10.1182/blood.v110.11.3832.3832.

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Abstract With the advent of high performance liquid chromatography (HPLC) accurate and precise measurement of hemoglobin A2 has been available for over 20 years. When microcytosis is present an elevated A2 is used as a surrogate marker for identification of beta thalassemia carriers. This combination is a very useful screening test. In contrast, A2 measurement in the low range is used to a lesser extent in screening for alpha thalassemia, delta chain variants and delta thalassemia. In the absence of structural variants A2 measurement by HPLC is accurate in the normal, high, and low ranges. This accuracy however does not hold true when samples harbor structural variants, particularly in the presence of Hb S as there are glycated and degraded fractions of S that co-elute with A2, thus falsely elevating the A2 value. In addition, with E and “D” type variants there is no A2 result or a falsely decreased value because A2 partially or completely co-elutes with the variant. In contrast to HPLC, capillary zone electrophoresis (CZE) separates the hemoglobin fractions according to their electrophoretic mobility with an alkaline buffer. We compared HbA2 measurement by high resolution (HR) HPLC (Primus Diagnostics) and CZE (Sebia CapillaryS) in samples without structural variants in the normal, high, and low ranges and in samples containing common structural variants. The 112 normals were from healthy, hematologically normal adult volunteers. The 20 samples in the high A2 range did not include structural variants and all had microcytosis. The 42 low A2 samples were from individuals without microcytosis in whom isoelectricfocusing (IEF) was also performed to identify delta chain variants. The heterozygotes for S, C, E and “D” had adult phenotypes and based on the percentages of the variant did not appear to have alpha thalassemia. In the “D” group there were 6 D-Punjab, 1 Osu-Christiansburg, and 1 Korle-Bu. G-Philadelphia was excluded as it occurs in association with alpha thalassemia. The results of our comparison study are shown in Table I. Besides what is indicated in the table we identified 9 individuals in the low A2 group that had delta chain variants identified on CZE but silent on HR-HPLC. These delta variants were confirmed by IEF. In summary, in the absence of structural variants these data indicate excellent correlation between HR-HPLC and CZE in the normal, high and low A2 ranges. In the low A2 range CZE has an added advantage over HR-HPLC in detecting delta variants. In the C-Trait group both methodologies appear equivalent but as expected in the S-Trait, E-Trait, and “D” Trait groups the CZE value appears to be more accurate. Compared to the normal group, however, there is a slight positive bias in S-Trait and E-Trait. In conclusion both methodologies appear complementary and can be used in combination for greater accuracy in hemoglobin identification and quantification of fractions. Table I Parameter N HR-HPLC Mean HR-HPLC 1 SD CZE Mean CZE 1 SD y R value Normal range A2 (1.8–3.5) 112 2.6 0.17 2.6 0.15 1.02 0.90 High range A2 > 3.6 20 5.1 0.59 5.0 0.5 0.98 0.94 Low range A <1.8 42 1.4 0.25 1.5 0.29 1.08 0.91 S Trait 32 4.0 0.25 3.1 0.18 0.76 0.66 C trait 15 3.1 0.28 3.1 0.3 0.98 0.66 E Trait 12 2.0 0.55 3.4 0.41 1.52 0.38 “D” Trait 8 N/A N/A 2.9 0.18 N/A N/A

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Lawrence, Phillip T., Marissa P. Grotzke, Yanina Rosenblum, Richard E. Nelson, Joanne LaFleur, Karla L. Miller, Junjie Ma e Grant W. Cannon. "The Bone Health Team: A Team-Based Approach to Improving Osteoporosis Care for Primary Care Patients". Journal of Primary Care & Community Health 8, n. 3 (17 gennaio 2017): 135–40. http://dx.doi.org/10.1177/2150131916687888.

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Abstract (sommario):

Background: Significant improvements in secondary prevention of osteoporotic fractures have been noted with fracture liaison services. However, similar models for the primary prevention of such fractures have not been reported. Objective: To determine the impact of a Bone Health Team (BHT) on osteoporosis screening and treatment rates in U.S. veterans in primary care practices. Design: Historical cohort study of a primary care–based intervention of a BHT from February 2013 to February 2015. Setting: Community-based outpatient clinics of the Salt Lake City Veterans Affairs Health Care System. Participants: Men aged 70 years and older and women aged 65 years and older. Intervention: Enrollment in the BHT. Measurements: Rates of dual energy x-ray absorptiometry (DXA) completion, chart diagnosis of osteoporosis or osteopenia, completion of vitamin D measurement, and initiation of fracture reducing medication. Results: Our cohort consisted of 7644 individuals, 975 of whom were exposed to the BHT and 6669 of whom were not. Comparison of patients exposed to the BHT versus non-exposed subjects demonstrated a substantial increase in all outcome measures studied. Hazard ratios (HRs) from multivariable cox proportional hazard models were: measurement of vitamin D, HR = 1.619 ( P < .001); chart diagnosis of osteopenia, HR = 37.00 ( P < .001); chart diagnosis of osteoporosis, HR = 16.38 ( P < .001); osteoporosis medication, HR = 17.03 ( P < .001); and completion of DXA, HR = 139.9 ( P < .001). Conclusions and Relevance: The implementation of a dedicated BHT produced significantly increased rates of intermediate osteoporosis outcome measures in US veterans in primary care practices. Additional research describing medication adherence rates and cost-effectiveness is forthcoming.

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ZHENG, R. Y., J. WANG e S. RAMAKRISHNA. "RF SPUTTERED BISMUTH FERRITE THIN FILMS: EFFECT OF ANNEALING DURATION". Functional Materials Letters 01, n. 03 (dicembre 2008): 221–24. http://dx.doi.org/10.1142/s1793604708000447.

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Abstract (sommario):

Polycrystalline BFO thin films of similar thickness but subjected to different annealing durations (2 hr and 4 hr) were deposited on SRO / Pt / TiO 2/ SiO 2/ Si substrates via RF sputtering. Phase identification by using X-ray diffractions confirms the pure BFO phase of the thin films fabricated. Polarization–Electric Field (P–E) loop study measured at different frequencies shows that a longer annealing duration led to the formation of space charges in the BFO thin films and thus caused a poor ferroelectric property observed in the hysteresis loop. The results of leakage current measurement for the two BFO films are consistent with the ferroelectric measurement, where a higher leakage current is demonstrated by the BFO film annealed for 4 hr.

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Ting, Ming-Kuo, Pei-Ju Liao, I.-Wen Wu, Shuo-Wei Chen, Ning-I. Yang, Tzu-Yu Lin e Kuang-Hung Hsu. "Predicting Type 2 Diabetes Mellitus Occurrence Using Three-Dimensional Anthropometric Body Surface Scanning Measurements: A Prospective Cohort Study". Journal of Diabetes Research 2018 (8 luglio 2018): 1–10. http://dx.doi.org/10.1155/2018/6742384.

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Abstract (sommario):

Background. An accurate and comprehensive anthropometric measure for predicting type 2 diabetes mellitus (T2DM) has not yet been depicted. Methods. A total of 8450 nondiabetic participants were recruited during 2000–2010 in Taiwan. The cohort was followed up to the end of 2013, over an average of 8.87 years. At recruitment, participants completed a questionnaire related to basic demographics, lifestyle variables, personal disease history, and family disease history. 3D body surface scanning was used to obtain 35 anatomical measurements. A Cox proportional hazard model was used to conduct multivariable analyses. Results. A total of 2068 T2DM cases at an incidence rate of 27.59 × 10−3 (year−1) were identified during the follow-up period. Multivariable-adjusted hazard ratios (HRs) demonstrated that neck circumference (NC) (HR = 1.048; 95% CI = 1.033–1.064), waist width (WW) (HR = 1.061; 95% CI = 1.040–1.081), and left thigh circumference (TC) (HR = 0.984; 95% CI = 0.972–0.995) were significant predictors of the occurrence of T2DM. While dividing body measurement into median high/low groups, an increased risk of T2DM was observed among participants with a larger NC and smaller TC (HR = 1.375; 95% CI = 1.180–1.601) and a larger WW and smaller TC (HR = 1.278; 95% CI = 1.085–1.505) relative to other participants. Conclusions. This study suggests that as well as using traditional waist and TC measurements, NC can be used as an indicator to provide an early prediction of developing T2DM, while providing clues for future mechanistic investigations of T2DM.

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Gautam, Dhruba Kumar. "Strategic integration of HRM for organizational performance: Nepalese reality". South Asian Journal of Global Business Research 4, n. 1 (2 marzo 2015): 110–28. http://dx.doi.org/10.1108/sajgbr-10-2012-0119.

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Abstract (sommario):

Purpose – The purpose of this paper is to explore the extent of strategic integration between business strategy and human resource (HR) policies and their impact on organizational performance of public listed companies in Nepal. Design/methodology/approach – Exploratory cum descriptive research design is followed with structured questionnaire distributed to 105 publicly listed individual organizations as a unit of analysis and secondary source of information used to verify the performance result of perceptual measurement. Findings – Formulation of explicit mission and business strategies indicate that around half of the organizations are doing business without business strategy and just one-fourth organizations formulate explicit HR strategy in order to support business strategies. Among the respondent organizations, few organizations meet the requirement of high strategic integrating organizations that were performing better than organizations that were low integrating. Practical implications – This study provides sufficient evidences to Nepalese decision makers and academics that integration of business and HR strategies will have better impact on organizational performance. The result of this study motivates decision makers and academics, particularly South Asian, to understand the importance of investing in HR to raise organizational performance. Originality/value – Examining strategic integration for organizational performance is perhaps the first study which certainly contributes to the overall assessment HRM and its impact on organizational performance to the developing countries of South Asia, like Nepal and add values to the process of theoretical development as well as HR management.

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Stok, Kathryn S., Stephanie Finzel, Andrew J. Burghardt, Philip G. Conaghan e Cheryl Barnabe. "The SPECTRA Collaboration OMERACT Special Interest Group: Current Research and Future Directions". Journal of Rheumatology 44, n. 12 (1 agosto 2017): 1911–15. http://dx.doi.org/10.3899/jrheum.161197.

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Abstract (sommario):

Objective.High-resolution peripheral quantitative computed tomography (HR-pQCT) has the potential to improve radiographic progression determination in clinical trials and longitudinal observational studies. The goal of this work was to describe the current state of research presented at Outcome Measures in Rheumatology (OMERACT) 2016 and ensuing future directions outlined during discussion among attendees.Methods.At OMERACT 2016, SPECTRA (Study grouP for xtrEme-Computed Tomography in Rheumatoid Arthritis) introduced efforts to (1) validate the HR-pQCT according to OMERACT guidelines, focusing on rheumatoid arthritis (RA), and (2) find alternatives for automated joint space width (JSW) analysis. The Special Interest Group (SIG) was presented to patient research partners, physicians/researchers, and SIG leaders followed by a 40-min discussion on future directions.Results.A consensus definition for RA erosion using HR-pQCT was demonstrated through a systematic literature review and a Delphi exercise. Histopathology and perfusion studies were presented that analyzed the true characteristics of cortical breaks in HR-pQCT images, and to provide criterion validity. Results indicate that readers were able to discriminate between erosion and small vascular channels. Moderate reliability (ICC 0.206–0.871) of direct erosion size measures was shown, which improved (> 0.9) only when experienced readers were considered. Quantification of erosion size was presented for scoring, direct measurement, and volumetric approaches, as well as a reliability exercise for direct measurement. Three methods for JSW measurement were compared, all indicating excellent reproducibility with differences at the extremes (i.e., near-zero and joint edge thickness).Conclusion.Initial reports on HR-pQCT are promising; however, to consider its use in clinical trials and longitudinal observational studies, it is imperative to assess the responsiveness of erosion measurement quantification.

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Shir-Mohammadi, K., e S. F. Perry. "Expression of ion transport genes in ionocytes isolated from larval zebrafish (Danio rerio) exposed to acidic or Na+-deficient water". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 319, n. 4 (1 ottobre 2020): R412—R427. http://dx.doi.org/10.1152/ajpregu.00095.2020.

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Abstract (sommario):

In zebrafish ( Danio rerio), a specific ionocyte subtype, the H+-ATPase-rich (HR) cell, is presumed to be a significant site of transepithelial Na+ uptake/acid secretion. During acclimation to environments differing in ionic composition or pH, ionic and acid–base regulations are achieved by adjustments to the activity level of HR cell ion transport proteins. In previous studies, the quantitative assessment of mRNA levels for genes involved in ionic and acid–base regulations relied on measurements using homogenates derived from the whole body (larvae) or the gill (adult). Such studies cannot distinguish whether any differences in gene expression arise from adjustments of ionocyte subtype numbers or transcriptional regulation specifically within individual ionocytes. The goal of the present study was to use fluorescence-activated cell sorting to separate the HR cells from other cellular subpopulations to facilitate the measurement of gene expression of HR cell-specific transporters and enzymes from larvae exposed to low pH (pH 4.0) or low Na+ (5 μM) conditions. The data demonstrate that treatment of larvae with acidic water for 4 days postfertilization caused cell-specific increases in H+-ATPase ( atp6v1aa), ca17a, ca15a, nhe3b, and rhcgb mRNA in addition to increases in mRNA linked to cell proliferation. In fish exposed to low Na+, expression of nhe3b and rhcgb was increased owing to HR cell-specific regulation and elevated numbers of HR cells. Thus, the results of this study demonstrate that acclimation to low pH or low Na+ environmental conditions is facilitated by HR cell-specific transcriptional control and by HR cell proliferation.

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Mayarani, Mayarani, Eka Putra Syarif Hidayat, Nursama Heru Apriantoro, Robert Kristian e Muhammad Irsal. "Analysis Of Rooftop Skyshine Radiation Exposure With Angle Of Gantry Linear Accelerator 180° In Radiotherapy Unit Of Pertamina Central Hospital Jakarta". SANITAS : Jurnal Teknologi dan Seni Kesehatan 9, n. 1 (1 giugno 2018): 24–34. http://dx.doi.org/10.36525/sanitas.2018.4.

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Abstract (sommario):

Principally, the measurement of skyshine radiation exposure is important to be conducted if there is public activity in a certain place in which the source of radiation can emit its scattering radiation to all directions including to the rooftop of a Radiotherapy building. the Regulation of the Head of the National Nuclear Power Energy No. 8 Year 2011 Article 32a and No. 4 year 2013 article 23a namely 1 mSv/year. As for the design of this research, it is quantitative descriptive by conducting the measurement of radiation exposure to 44 points of measurement, research instrumentations used herein are 2 surveymeter, water phantom, Linac Primus 2D Plus. Result radiation exposure measurement are 6 point areas with the values above 1 mR/hr. Each of the average value of the measurement of the exposure rate at each point is calculated by the annual dose formula. All the final calculation results with the annual dose formula in mSv/year unit yields the values below 1 mSv/year at the 44 points measurement. the rooftop area of Radiotherapy building through Child Polyclinic Pertamina Central Hospital is under a safe limit with all calculation results of annual dose values below 1 mSv/year.

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Stuver, Sherri O., Jennifer Lyons, Andrea Coviello e Lisa Fredman. "Feasibility of 24-Hr Urine Collection for Measurement of Biomarkers in Community-Dwelling Older Adults". Journal of Applied Gerontology 36, n. 11 (12 gennaio 2016): 1393–408. http://dx.doi.org/10.1177/0733464815624153.

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Abstract (sommario):

Biologic markers are becoming a key part of gerontological research, including their measurement at multiple intervals to detect changes over time. This report examined the feasibility and quality of 24-hr urine collection to measure neuroendocrine biomarkers in a community-based sample of older caregivers and non-caregivers. At each interview, participants were instructed on the correct method to collect and store the sample. As incentives, participants selected a day for urine collection within 5 days of the interview, received a reimbursement, and study staff travelled to their home to retrieve the specimen. Between 2008 and 2013, 256 participants were enrolled; all but two participants (99%) provided a baseline urine specimen, of which 93% were considered adequate. Urine collection and quality remained high over three annual follow-up interviews and did not vary by caregiver status or perceived stress level. Our results indicate that 24-hr urine collection is feasible in active, community-dwelling older adults.

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Goodman, L. J., J. K. Weston, A. Mukherjee, J. Sperinde, A. Paquet, S. Williams, G. Parry, M. Bates, W. Koestler e A. Lipton. "Quantitative measurement of HER3 total protein (H3T) and association with clinical outcome in HER2-positive metastatic breast cancer patients treated with trastuzumab". Journal of Clinical Oncology 27, n. 15_suppl (20 maggio 2009): 1021. http://dx.doi.org/10.1200/jco.2009.27.15_suppl.1021.

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Abstract (sommario):

1021 Background: The heterodimerization of HER3, with HER2 and the subsequent activation of the AKT pathway, has been implicated in both regulation of tumor cell growth and in resistance to HER2 targeted therapies such as trastuzumab. Currently available methods of measuring H3T in formalin-fixed, paraffin-embedded (FFPE) samples are insufficiently sensitive or specific; thus the impact of quantitative measurement of H3T expression on clinical response to trastuzumab has not been evaluated. Methods: We have developed a highly quantitative, accurate, precise, sensitive, and reproducible H3T assay in FFPE samples based on the VeraTag technology platform. Consequently, the H3T assay displays ∼5-fold greater sensitivity than conventional IHC measurements. Additionally, the rank order and accuracy of the H3T measurements were preserved over a wide dynamic range in well-characterized cell line panels. Intra- and inter-assay reproducibility measurements demonstrated 7–11 %CV and 8–16 % CV, respectively. Results: Quantitative levels of HER2 total protein (H2T) and H3T expression were determined by the VeraTag technology in 81 tumors from patients with trastuzumab-treated metastatic breast cancer. A previously reported H2T cutoff was used to sub-divide the patients into HER2-normal (N = 26, median TTP = 4.1 mos) and HER2-overexpressing (N = 55, median TTP = 11.1 mos, HR = 0.43, p = 0.0002) groups. In the HER2-overexpressing group, high H3T expression, as defined by a positional scanning cutoff analysis, predicted shorter median time to progression (N = 25, median TTP = 6.1 mos) compared with low H3T expression (N = 30, median TTP = 13.1 mos, HR = 2.7, p = 0.0002). Univariate Cox proportional hazards analyses examining the HER2-overexpressing subgroup identified H3T (high vs. low) as the most significant predictor of TTP (HR = 2.98, p = 0.0004). Conclusions: These results demonstrate that the accurate and sensitive measurement of H3T in a cohort of patients with HER-2 positive breast cancer predicts TTP in response to trastuzumab and could indicate a population of patients with worse outcome requiring additional therapeutic intervention. [Table: see text]

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Beghin, L., L. Michaud, D. Guimber, G. Vaksmann, D. Turck e F. Gottrand. "Assessing sleeping energy expenditure in children using heart-rate monitoring calibrated against open-circuit indirect calorimetry: a pilot study". British Journal of Nutrition 88, n. 5 (novembre 2002): 533–43. http://dx.doi.org/10.1079/bjn2002708.

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Abstract (sommario):

Total energy expenditure (EE) can be assessed in children by the heart-rate (HR) monitoring technique calibrated against open-circuit indirect calorimetry (IC). In this technique, sleeping EE is usually estimated as the lowest value of a 30 min resting EE measurement×0·90 to give an average for the total sleeping period. However, sleeping is a dynamic process in which sleeping EE is modulated by the effect of factors such as body movement and different sleep stages. The aim of the present study was to determine a new method to improve the sleeping EE measurement by taking into account body movements during sleep. Twenty-four non-obese children participated in the present study. All subjects passed through a calibration period. HR and EE measured by IC were simultaneously collected during resting, the postprandial period, and during different levels of activity. Different methods for computing sleeping EE (resting EE×0·90 with different breakpoints (‘flex point’ HR with linear regression or ‘inflection point’ (IP) HR with the third order polynomial regression equation (P3)) were compared with EE measured for least 2·0 h in eight sleeping children. The best method of calculation was then tested in sixteen children undergoing HR monitoring and with a body movement detector. In a subset of eight children undergoing simultaneous sleeping EE measurement by IC and HR, the use of the equation resting EE×0·8 when HR<IP and P3 when HR>IP during the sleeping period gave the lowest difference (1 (SD 5·4) %) compared with other methods (linear or polynomial regressions). The new formula was tested in an independent subset of sixteen other children. The difference between sleeping ee computed with the formula resting EE×0·90 and sleeping EE computed with resting EE×0·8 when HR<IP and the P3 equation when HR>IP during sleeping periods was significant (13 (sd 5·9)%) only for active sleeping subjects (n 6 of 16 subjects). The correlation between the difference in the results from the two methods of calculation and body movements was close (r 0·63, P<0·005, Spearman test) as well as computed sleeping EE (Spearman test, r 0·679, P<0·001), indicating that this new method is reliable for computing sleeping EE with HR monitoring if children are moving during sleep and improves the total EE assessment.

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Farley, Richard S., Phillip A. Bishop e Paul Ray. "Evaluation of Half-Mask Gas Collection for Metabolic Measurement in the Work Place". Proceedings of the Human Factors and Ergonomics Society Annual Meeting 38, n. 17 (ottobre 1994): 1109–12. http://dx.doi.org/10.1177/154193129403801708.

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Abstract (sommario):

Metabolic measurement is often important in job design and research. Metabolic measurement via indirect spirometry has traditionally used a mouth-piece nose-clip headgear (MNH) method of collecting expired gases. MNH is often uncomfortable, prohibits oral communication, may fail because of loss of nose-clip, and may interfere with or alter some work tasks because of the awkwardness of the headgear. Gas collection masks (MASK) offer the possibility of partially or totally alleviating the problems of MNH but increase the possibility of erroneous measure due to leakage. This study compared the measurement of performance and subject's subjective ratings of a typical MNH vs. MASK (Hans Rudolph model 8900 series) over a range of work loads from light to maximal in 20 well-trained subjects (M=12, F=8). Ventilation (Ve), oxygen uptake (VO2), and respiratory exchange ratio (RER) were collected with a Sensormedics MMC-1, and heart rate (HR) with a Polar Heartwatch. Comfort was assessed with a Likert questionnaire. Results from the final work rate are shown below: Variable Ve (L/min) VO2 (ml/kg/min) RER HR (bpm) MNH 105,217 52.2 1.13 187 MASK 115,281 56.6 1.09 187 Results show this MASK produced values as high as the MNH with greater subject comfort at both peak and sub-maximal work. The observed Ve in the MASK condition suggests that leakage was not problematic and there could be a tendency for the MNH to actually impede the measurement. Based on previous preliminary studies and these data, careful use of the MASK is recommended over MNH for work place metabolic or other ventilatory measurements.

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Polanco, Nicole, Sharon Odametey, Neda Derakhshani, Mark Khachaturian, Connor Devoe, Kamal Jethwani e Sujay Kakarmath. "Evaluating the Accuracy of an Integrated Vital Sign Measurement Wellness Device". Iproceedings 5, n. 1 (2 ottobre 2019): e15203. http://dx.doi.org/10.2196/15203.

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Abstract (sommario):

Background Wellness devices for health tracking have gained popularity in recent years. Additionally, portable and readily accessible wellness devices have several advantages when compared to traditional medical devices found in clinical environments. Building tools for patients to manage their health independently may benefit their health in the long run by improving health care providers’ (HCPs) awareness of their patients’ health information outside of the clinic. Increased access to portable wellness devices that track vital signs may increase how patients and HCPs track and monitor chronic conditions which can improve health outcomes. The VitalWellness is a portable wellness device that can potentially aid vital sign measuring for those interested in tracking their health. Objective In this diagnostic accuracy study, we evaluated the clinical performance of the VitalWellness, a wireless, compact, non-invasive device that measures four vital signs using the index finger and forehead against reference vital signs devices used in the hospital setting. Methods Volunteers age ≥18 years were enrolled to provide blood pressure (BP), heart rate (HR), respiratory rate (RR), and body temperature. We recruited volunteers with vital signs that fell within and outside of the normal physiological range, depending on the measurements they consented to undergo. A subgroup of eligible volunteers were asked to undergo an exercise test, aerobic step test and/or a paced breathing test to analyze the VitalWellness device's performance on vital signs outside of the normal physiological ranges for HR and RR. Vital signs measurements were collected with the VitalWellness device and FDA-approved reference devices. Mean, standard deviation, mean difference, standard deviation of difference, standard error of mean difference, and correlation coefficients were calculated for measurements collected; these measurements were plotted on a scatter plot and a Bland-Altman plot. Sensitivity analyses were performed to evaluate the performance of the VitalWellness device by gender, skin color, finger size, and in the presence of artifacts. Results We enrolled 265 volunteers in the study and 2 withdrew before study completion. The majority of volunteers were female (62%), predominately white (63%), graduated from college or post college (67%), and employed (59%). There was a moderately strong linear relationship between VitalWellness BP and reference BP (r=0.7, P<.05) and bewteen VitalWellness RR and reference RR measurements (r=0.7, P<.05). The VitalWellness HR readings were significantly in line with the reference HR readings (r=0.9, P<.05). There was a weaker linear relationship between VitalWellness temperature and reference temperature (r=0.3, P<.05). There were no differences in performance of the VitalWellness device by gender, skin color or in the presence of artifacts. Finger size was associated with differential performance for RR. Conclusions Overall, the VitalWellness device performed well in taking BP, HR and RR when compared to FDA-approved reference devices and has potential serve as a wellness device. To test adaptability and acceptability, future research may evaluate user’s interactions and experiences with the VitalWellness device at home. In addition, the next phase of the study will evaluate transmitting vital sign information from the VitalWellness device to an online secured database where information can be shared with HCPs within seconds of measurement.

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Runesson, Björn, Marco Trevisan, Ken Iseri, Abdul Rashid Qureshi, Bengt Lindholm, Peter Barany, Carl Gustaf Elinder e Juan Jesus Carrero. "Fractures and their sequelae in non-dialysis-dependent chronic kidney disease: the Stockholm CREAtinine Measurement project". Nephrology Dialysis Transplantation 35, n. 11 (30 luglio 2019): 1908–15. http://dx.doi.org/10.1093/ndt/gfz142.

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Abstract Introduction People undergoing maintenance dialysis are at high risk for fractures, but less is known about fracture incidence and associated outcomes in earlier stages of chronic kidney disease (CKD). Methods We conducted an observational analysis from the Stockholm Creatinine Measurement project, a Swedish health care utilization cohort during 2006–11. We identified all adults with confirmed CKD Stages 3–5 and no documented history of fractures and extracted information on comorbid history, ongoing medication, cardiovascular events and death. We studied incidence rates of fractures (overall and by location), with the estimated glomerular filtration rate (eGFR) as time-dependent exposure. We then studied hazard ratios [HRs and 95% confidence intervals (CIs)] for the events of death and major adverse cardiac events (MACE) using Cox regression with fracture as time-varying exposure. Results We identified 68 764 individuals with confirmed CKD (mean age 79 years, 56% women). During a median follow-up of 2.7 years, 9219 fractures occurred, of which 3105 were hip fractures. A more severe CKD stage was associated with a higher risk of fractures, particularly hip fractures: compared with CKD Stage 3a, the adjusted HR was 1.10 (95% CI 1.02–1.19), 1.32 (1.17–1.49) and 2.47 (1.94–3.15) for CKD Stage 3b, 4 and 5, respectively. Spline curves suggested a linear association with fracture risk with an eGFR <30 mL/min/1.73 m2. Compared with non-fracture periods, incident fracture was associated with a 4-fold increased mortality within 90 days [HR 4.21 (95% CI 3.95–4.49)]. The risk remained elevated beyond 90 days [HR 1.47 (95% CI 1.40–1.54)] and was stronger after hip fractures. Post-fracture MACE risk was also highest in the first 90 days [HR 4.02 (95% CI 3.73–4.33)], particularly after hip fractures, and persisted beyond 90 days [HR 1.20 (95% CI 1.10–1.30)]. Conclusion Our findings highlight the commonness of fractures and the increased risk for subsequent adverse outcomes in CKD patients. These results may inform clinical decisions regarding post-fracture clinical surveillance and fracture prevention strategies.

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Wang, Meiqing, Ali Youssef, Mona Larsen, Jean-Loup Rault, Daniel Berckmans, Jeremy N. Marchant-Forde, Joerg Hartung, André Bleich, Mingzhou Lu e Tomas Norton. "Contactless Video-Based Heart Rate Monitoring of a Resting and an Anesthetized Pig". Animals 11, n. 2 (8 febbraio 2021): 442. http://dx.doi.org/10.3390/ani11020442.

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Heart rate (HR) is a vital bio-signal that is relatively easy to monitor with contact sensors and is related to a living organism’s state of health, stress and well-being. The objective of this study was to develop an algorithm to extract HR (in beats per minute) of an anesthetized and a resting pig from raw video data as a first step towards continuous monitoring of health and welfare of pigs. Data were obtained from two experiments, wherein the pigs were video recorded whilst wearing an electrocardiography (ECG) monitoring system as gold standard (GS). In order to develop the algorithm, this study used a bandpass filter to remove noise. Then, a short-time Fourier transform (STFT) method was tested by evaluating different window sizes and window functions to accurately identify the HR. The resulting algorithm was first tested on videos of an anesthetized pig that maintained a relatively constant HR. The GS HR measurements for the anesthetized pig had a mean value of 71.76 bpm and standard deviation (SD) of 3.57 bpm. The developed algorithm had 2.33 bpm in mean absolute error (MAE), 3.09 bpm in root mean square error (RMSE) and 67% in HR estimation error below 3.5 bpm (PE3.5). The sensitivity of the algorithm was then tested on the video of a non-anaesthetized resting pig, as an animal in this state has more fluctuations in HR than an anaesthetized pig, while motion artefacts are still minimized due to resting. The GS HR measurements for the resting pig had a mean value of 161.43 bpm and SD of 10.11 bpm. The video-extracted HR showed a performance of 4.69 bpm in MAE, 6.43 bpm in RMSE and 57% in PE3.5. The results showed that HR monitoring using only the green channel of the video signal was better than using three color channels, which reduces computing complexity. By comparing different regions of interest (ROI), the region around the abdomen was found physiologically better than the face and front leg parts. In summary, the developed algorithm based on video data has potential to be used for contactless HR measurement and may be applied on resting pigs for real-time monitoring of their health and welfare status, which is of significant interest for veterinarians and farmers.

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Fernandez, Julie. "The ball of wax we call HR analytics". Strategic HR Review 18, n. 1 (11 febbraio 2019): 21–25. http://dx.doi.org/10.1108/shr-09-2018-0077.

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Purpose The debate surrounding automating analytics processes continues as technology becomes more prominent and advanced in the workplace. Specifically, when it comes to HR analytics, it is important to recognize that human judgment as it is used in recruiting today is flawed. One tool that can provide further analysis and measurement beyond performance indicators and predictors is machine learning. Through automation, HR professionals may someday be able to compare characteristics, apply regression analysis to identify the influence of a characteristic and make adjustments based on new hires, retention and promotion results. Design/methodology/approach With more and more companies using artificial intelligence, it is difficult to see how it will revolutionize the HR process. As humans already have biases, will they transfer over to these artificial intelligence machines? Human judgment is already flawed in the recruiting process, so it is crucial to take a look into how it plays a role when AI is becoming built into the process as well. Findings Advancements in automation and HR technology are not slowing down anytime soon. As HR departments become increasingly reliant on advanced technologies and the numbers they produce, they also will experience the need for new skillsets required to deploy and use them. The HR process is rapidly changing, and as people, we must adapt now to see how AI is going to affect it. With a growing need for a center of expertise (COE) for HR data and technology, we will need to use this to focus resources on workforce analytics to drive business insights and recommendations. Originality/value This paper discusses the importance of understanding the implications of advanced analytics on recruiting and people management.

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Aliyu, Abubakar Sadiq, Aminu Ismaila, A. M. Na'Inna e Ahmed Mohammed. "MEASUREMENT OF RADON CONCENTRATION IN SOIL SAMPLES OF MAZAT AND KAFI-HABU MINING SITES, PLATEAU, NIGERIA". FUDMA JOURNAL OF SCIENCES 4, n. 4 (13 giugno 2021): 295–301. http://dx.doi.org/10.33003/fjs-2020-0404-485.

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Radon and its short-lived progenies contributed significantly to natural background radiation. Long-term exposure to such radiation increases the probability of lung cancer to persons. To assess the radiological hazards associated with the inhalation of radon gas from ore dust in Mazat and Kafi-Habu mining sites of Plateau, Nigeria, 12 soil samples from an abandoned tailing dump ground were collected and analysed for radon using RAD-7 electronic detector. The dose rate of each sampling point was directly measured using RADOS RDS -120 portable survey meter. The results gave a mean radon concentration ranging from 771.51 ± 21.9 Bq/m3 to 5666.13 ± 28.8 Bq/m3 with 3451.13 ± 42.9 Bq/m3as the average value for all measurements. The average concentration of measurements from Mazat and Kafi-Habu is 3671.6 ± 41.2 Bq/m3 and 3010.16 ± 46.5 Bq/m3 respectively. The average values obtained from the analysis are significantly higher than the upper limit of 300 Bq/m3 set by the International Commission on Radiological Protection (ICRP) suggesting quick remediation on the host communities. The geometrical mean value of Dose Rate (DR) and Annual Effective Dose Equivalent (AEDE) were 870 nGy/hr and 1.04 mSv/yr respectively. Again, these values are above the global average limits of 59 nGy/hr and 1 mSv/yr. The result indicates that miners working in those sites and dwellers of the study areas are at higher risk of getting exposed to radon and need to employ protective measures. This work is useful in monitoring and control of radon level for the on-site workers and the

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