Journal articles: 'RFF'

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Lien, Yu-An S., Carolyn R. Calabrese, Carolyn M. Michener, Elizabeth Heller Murray, Jarrad H. Van Stan, Daryush D. Mehta, Robert E. Hillman, J. Pieter Noordzij, and Cara E. Stepp. "Voice Relative Fundamental Frequency Via Neck-Skin Acceleration in Individuals With Voice Disorders." Journal of Speech, Language, and Hearing Research 58, no. 5 (October 2015): 1482–87. http://dx.doi.org/10.1044/2015_jslhr-s-15-0126.

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Purpose This study investigated the use of neck-skin acceleration for relative fundamental frequency (RFF) analysis. Method Forty individuals with voice disorders associated with vocal hyperfunction and 20 age- and sex-matched control participants were recorded with a subglottal neck-surface accelerometer and a microphone while producing speech stimuli appropriate for RFF. Rater reliabilities, RFF means, and RFF standard deviations derived from the accelerometer were compared with those derived from the microphone. Results RFF estimated from the accelerometer had slightly higher intrarater reliability and identical interrater reliability compared with values estimated with the microphone. Although sensor type and the Vocal Cycle × Sensor and Vocal Cycle × Sensor × Group interactions showed significant effects on RFF means, the typical RFF pattern could be derived from either sensor. For both sensors, the RFF of individuals with vocal hyperfunction was lower than that of the controls. Sensor type and its interactions did not have significant effects on RFF standard deviations. Conclusions RFF can be reliably estimated using an accelerometer, but these values cannot be compared with those collected via microphone. Future studies are needed to determine the physiological basis of RFF and examine the effect of sensors on RFF in practical voice assessment and monitoring settings.

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Puckett, Susan E., Kaleb A. Reese, Georgi M. Mitev, Valerie Mullen, Rudd C. Johnson, Kyle R. Pomraning, Brett L. Mellbye, et al. "Bacterial Resistance to Antisense Peptide Phosphorodiamidate Morpholino Oligomers." Antimicrobial Agents and Chemotherapy 56, no. 12 (September 17, 2012): 6147–53. http://dx.doi.org/10.1128/aac.00850-12.

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ABSTRACTPeptide phosphorodiamidate morpholino oligomers (PPMOs) are synthetic DNA mimics that bind cRNA and inhibit bacterial gene expression. The PPMO (RFF)3RXB-AcpP (where R is arginine, F, phenylalanine, X is 6-aminohexanoic acid, B is β-alanine, and AcpP is acyl carrier protein) is complementary to 11 bases of the essential geneacpP(which encodes acyl carrier protein). The MIC of (RFF)3RXB-AcpP was 2.5 μM (14 μg/ml) inEscherichia coliW3110. The rate of spontaneous resistance ofE. colito (RFF)3RXB-AcpP was 4 × 10−7mutations/cell division. A spontaneous (RFF)3RXB-AcpP-resistant mutant (PR200.1) was isolated. The MIC of (RFF)3RXB-AcpP was 40 μM (224 μg/ml) for PR200.1. The MICs of standard antibiotics for PR200.1 and W3110 were identical. The sequence ofacpPwas identical in PR200.1 and W3110. PR200.1 was also resistant to other PPMOs conjugated to (RFF)3RXB or peptides with a similar composition or pattern of cationic and nonpolar residues. Genomic sequencing of PR200.1 identified a mutation insbmA, which encodes an active transport protein. In separate experiments, a (RFF)3RXB-AcpP-resistant isolate (RR3) was selected from a transposome library, and the insertion was mapped tosbmA. Genetic complementation of PR200.1 or RR3 withsbmArestored susceptibility to (RFF)3RXB-AcpP. Deletion ofsbmAcaused resistance to (RFF)3RXB-AcpP. We conclude that resistance to (RFF)3RXB-AcpP was linked to the peptide and not the phosphorodiamidate morpholino oligomer, dependent on the composition or repeating pattern of amino acids, and caused by mutations insbmA. The data further suggest that (RFF)3R-XB PPMOs may be transported across the plasma membrane by SbmA.

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Dahl, Kimberly L., and Cara E. Stepp. "Changes in Relative Fundamental Frequency Under Increased Cognitive Load in Individuals With Healthy Voices." Journal of Speech, Language, and Hearing Research 64, no. 4 (April 14, 2021): 1189–96. http://dx.doi.org/10.1044/2021_jslhr-20-00134.

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Purpose The purpose of this study was to determine the effect of cognitive load on relative fundamental frequency (RFF) in individuals with healthy voices. Method Twenty adults with healthy voices read sentences under different cognitive load conditions. Each sentence contained color terms printed in colored ink, creating an embedded Stroop task. Participants read the ink color in which a word was printed, rather than the color term itself. Sentences with mismatched ink colors and printed words constituted an increased cognitive load. RFF, an acoustic correlate of laryngeal tension, was calculated for the 10 voicing cycles preceding (i.e., offset) and following (i.e., onset) voiceless consonants. Repeated measures analyses of variance were constructed to assess the effects of RFF cycle, cognitive load, and their interaction on mean RFF offset and onset. Results There was a significant effect of cognitive load condition on RFF offset. There was no significant effect of condition on RFF onset nor significant interaction between cycle and condition on RFF onset or offset values. Conclusion Reduced mean RFF offset may indicate an increase in laryngeal muscle tension during a cognitively demanding task.

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Roy, Nelson, Rebecca A. Fetrow, Ray M. Merrill, and Christopher Dromey. "Exploring the Clinical Utility of Relative Fundamental Frequency as an Objective Measure of Vocal Hyperfunction." Journal of Speech, Language, and Hearing Research 59, no. 5 (October 2016): 1002–17. http://dx.doi.org/10.1044/2016_jslhr-s-15-0354.

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Purpose Vocal hyperfunction, related to abnormal laryngeal muscle activity, is considered the proximal cause of primary muscle tension dysphonia (pMTD). Relative fundamental frequency (RFF) has been proposed as an objective acoustic marker of vocal hyperfunction. This study examined (a) the ability of RFF to track changes in vocal hyperfunction after treatment for pMTD and (b) the influence of dysphonia severity, among other factors, on the feasibility of RFF computation. Method RFF calculations and dysphonia severity ratings were derived from pre- and posttreatment recordings from 111 women with pMTD and 20 healthy controls. Three vowel–voiceless consonant–vowel stimuli were analyzed. Results RFF onset slope consistently varied as a function of group (pMTD vs. controls) and time (pretherapy vs. posttherapy). Significant correlations between RFF onset cycle 1 and dysphonia severity were observed. However, in many samples, RFF could not be computed, and adjusted odds ratios revealed that these unanalyzable data were linked to dysphonia severity, phonetic (vowel–voiceless consonant–vowel) context, and group (pMTD vs. control). Conclusions RFF onset appears to be sensitive to the presence and degree of suspected vocal hyperfunction before and after therapy. The large number of unanalyzable samples (related especially to dysphonia severity in the pMTD group) represents an important limitation.

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Heller Murray, Elizabeth S., Roxanne K. Segina, Geralyn Harvey Woodnorth, and Cara E. Stepp. "Relative Fundamental Frequency in Children With and Without Vocal Fold Nodules." Journal of Speech, Language, and Hearing Research 63, no. 2 (February 26, 2020): 361–71. http://dx.doi.org/10.1044/2019_jslhr-19-00058.

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Purpose Relative fundamental frequency (RFF) is an acoustic measure that is sensitive to functional voice differences in adults. The aim of the current study was to evaluate RFF in children, as there are known structural and functional differences between the pediatric and adult vocal mechanisms. Method RFF was analyzed in 28 children with vocal fold nodules (CwVN, M = 9.0 years) and 28 children with typical voices (CwTV, M = 8.9 years). RFF is the instantaneous fundamental frequency ( f 0 ) of the 10 vocalic cycles during devoicing (vocal offset) and 10 vocalic cycles during the revoicing (vocal onset) of the vowels that surround a voiceless consonant. Each cycle's f 0 was normalized to a steady-state portion of the vowel. RFF values for the cycles closest to the voiceless consonant, that is, Offset Cycle 10 and Onset Cycle 1, were examined. Results Average RFF values for Offset Cycle 10 and Onset Cycle 1 did not differ between CwVN and CwTV; however, within-subject variability of Offset Cycle 10 was decreased in CwVN. Across both groups, male children had lower Offset Cycle 10 RFF values as compared to female children. Additionally, Onset Cycle 1 values were decreased in younger children as compared to those of older children. Conclusions Unlike previous work with adults, CwVN did not have significantly different RFF values than CwTV. Younger children had lower RFF values for Onset Cycle 1 than older children, suggesting that vocal onset f 0 may provide information on the maturity of the laryngeal motor system.

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Wang, Wenbo, Ignacio Aguilar Sanchez, Gianluca Caparra, Andy McKeown, Tim Whitworth, and Elena Simona Lohan. "A Survey of Spoofer Detection Techniques via Radio Frequency Fingerprinting with Focus on the GNSS Pre-Correlation Sampled Data." Sensors 21, no. 9 (April 25, 2021): 3012. http://dx.doi.org/10.3390/s21093012.

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Radio frequency fingerprinting (RFF) methods are becoming more and more popular in the context of identifying genuine transmitters and distinguishing them from malicious or non-authorized transmitters, such as spoofers and jammers. RFF approaches have been studied to a moderate-to-great extent in the context of non-GNSS transmitters, such as WiFi, IoT, or cellular transmitters, but they have not yet been addressed much in the context of GNSS transmitters. In addition, the few RFF-related works in GNSS context are based on post-correlation or navigation data and no author has yet addressed the RFF problem in GNSS with pre-correlation data. Moreover, RFF methods in any of the three domains (pre-correlation, post-correlation, or navigation) are still hard to be found in the context of GNSS. The goal of this paper was two-fold: first, to provide a comprehensive survey of the RFF methods applicable in the GNSS context; and secondly, to propose a novel RFF methodology for spoofing detection, with a focus on GNSS pre-correlation data, but also applicable in a wider context. In order to support our proposed methodology, we qualitatively investigated the capability of different methods to be used in the context of pre-correlation sampled GNSS data, and we present a simulation-based example, under ideal noise conditions, of how the feature down selection can be done. We are also pointing out which of the transmitter features are likely to play the biggest roles in the RFF in GNSS, and which features are likely to fail in helping RFF-based spoofing detection.

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Park, Yeonggwang, and Cara E. Stepp. "Test–Retest Reliability of Relative Fundamental Frequency and Conventional Acoustic, Aerodynamic, and Perceptual Measures in Individuals With Healthy Voices." Journal of Speech, Language, and Hearing Research 62, no. 6 (June 19, 2019): 1707–18. http://dx.doi.org/10.1044/2019_jslhr-s-18-0507.

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Purpose Recent studies have shown that an acoustic measure, relative fundamental frequency (RFF), has potential for the assessment of excessive laryngeal tension and vocal effort associated with functional and neurological voice disorders. This study presents an analysis of the test–retest reliability of RFF in individuals with healthy voices and a comparison of reliability between RFF and conventional measures of voice. Method Acoustic and aerodynamic measurements and Consensus Auditory–Perceptual Evaluation of Voice (CAPE-V) were performed on 28 individuals with healthy voices on 5 consecutive days. Participants produced RFF stimuli, a sustained /ɑ/, and a reading passage to allow for extraction of acoustic measures and CAPE-V ratings; /pa/ trains were produced to allow for extraction of aerodynamic measures. Results Moderate reliabilities (intraclass correlation coefficient [ICC] = .64–.71) were found for RFF values. Mean vocal fundamental frequency, smoothed cepstral peak prominence, shimmer, harmonics-to-noise ratio, and mean airflow rate exhibited good-to-excellent reliabilities (ICC = .76–.99). ICCs for jitter and phonation threshold pressure were moderately reliable (ICC = .67–.74). ICCs for subglottal pressure estimates and all CAPE-V parameters showed poor reliabilities (ICC = .31–.58). Conclusion RFF has comparable reliability to conventional measures of voice. This expands the potential for clinical application of RFF. Supplemental Material https://doi.org/10.23641/asha.8233376

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Vojtech, Jennifer M., Dante D. Cilento, Austin T. Luong, Jacob P. Noordzij, Manuel Diaz-Cadiz, Matti D. Groll, Daniel P. Buckley, Victoria S. McKenna, J. Pieter Noordzij, and Cara E. Stepp. "Acoustic Identification of the Voicing Boundary during Intervocalic Offsets and Onsets Based on Vocal Fold Vibratory Measures." Applied Sciences 11, no. 9 (April 23, 2021): 3816. http://dx.doi.org/10.3390/app11093816.

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Methods for automating relative fundamental frequency (RFF)—an acoustic estimate of laryngeal tension—rely on manual identification of voiced/unvoiced boundaries from acoustic signals. This study determined the effect of incorporating features derived from vocal fold vibratory transitions for acoustic boundary detection. Simultaneous microphone and flexible nasendoscope recordings were collected from adults with typical voices (N = 69) and with voices characterized by excessive laryngeal tension (N = 53) producing voiced–unvoiced–voiced utterances. Acoustic features that coincided with vocal fold vibratory transitions were identified and incorporated into an automated RFF algorithm (“aRFF-APH”). Voiced/unvoiced boundary detection accuracy was compared between the aRFF-APH algorithm, a recently published version of the automated RFF algorithm (“aRFF-AP”), and gold-standard, manual RFF estimation. Chi-square tests were performed to characterize differences in boundary cycle identification accuracy among the three RFF estimation methods. Voiced/unvoiced boundary detection accuracy significantly differed by RFF estimation method for voicing offsets and onsets. Of 7721 productions, 76.0% of boundaries were accurately identified via the aRFF-APH algorithm, compared to 70.3% with the aRFF-AP algorithm and 20.4% with manual estimation. Incorporating acoustic features that corresponded with voiced/unvoiced boundaries led to improvements in boundary detection accuracy that surpassed the gold-standard method for calculating RFF.

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Park, Yeonggwang, Manuel Díaz Cádiz, Kathleen F. Nagle, and Cara E. Stepp. "Perceptual and Acoustic Assessment of Strain Using Synthetically Modified Voice Samples." Journal of Speech, Language, and Hearing Research 63, no. 12 (December 14, 2020): 3897–908. http://dx.doi.org/10.1044/2020_jslhr-20-00294.

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Purpose Assessment of strained voice quality is difficult due to the weak reliability of auditory-perceptual evaluation and lack of strong acoustic correlates. This study evaluated the contributions of relative fundamental frequency (RFF) and mid-to-high frequency noise to the perception of strain. Method Stimuli were created using recordings of speakers producing /ifi/ with a comfortable voice and with maximum vocal effort. RFF values of the comfortable voice samples were synthetically lowered, and RFF values of the maximum vocal effort samples were synthetically raised. Mid-to-high frequency noise was added to the samples. Twenty listeners rated strain in a visual sort-and-rate task. The effects of RFF modification and added noise on strain were assessed using an analysis of variance; intra- and interrater reliability were compared with and without noise. Results Lowering RFF in the comfortable voice samples increased their perceived strain, whereas raising RFF in the maximum vocal effort samples decreased their strain. Adding noise increased strain and decreased intra- and interrater reliability relative to samples without added noise. Conclusions Both RFF and mid-to-high frequency noise contribute to the perception of strain. The presence of dysphonia may decrease the reliability of auditory-perceptual evaluation of strain, which supports the need for complementary objective assessments. Supplemental Material https://doi.org/10.23641/asha.13172252

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Lien, Yu-An S., Caitlin I. Gattuccio, and Cara E. Stepp. "Effects of Phonetic Context on Relative Fundamental Frequency." Journal of Speech, Language, and Hearing Research 57, no. 4 (August 2014): 1259–67. http://dx.doi.org/10.1044/2014_jslhr-s-13-0158.

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Purpose The effect of phonetic context on relative fundamental frequency (RFF) was examined, in order to develop stimuli sets with minimal within-speaker variability that can be implemented in future clinical protocols. Method Sixteen speakers with healthy voices produced RFF stimuli. Uniform utterances consisted of 3 repetitions of the same voiced sonorant-voiceless consonant-voiced sonorant speech sequence; moderately variable sentences contained speech sequences with a single voiceless phoneme (/f/, /s/, /ʃ/, /p/, /t/, or /k/); highly variable sentences were loaded with speech sequences using multiple phonemes. Effects of stimulus type (uniform, moderately variable, and highly variable) and phoneme identity (/f/, /s/, /ʃ/, /p/, /t/, and /k/) on RFF means and standard deviations were determined. Results Stimulus type and the interaction of vocal cycle and stimulus type were significant for RFF means and standard deviations but with small effect sizes. Phoneme identity and the interaction of vocal cycle and phoneme identity on RFF means and standard deviations were also significant with small to medium effect sizes. Conclusions For speakers with healthy voices, uniform utterances with /f/ and /ʃ/ have the lowest standard deviations and thus are recommended for RFF-based assessments. Future work is necessary to extend these findings to disordered voices.

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Zhang, Zhen, Yibing Li, Chao Wang, Meiyu Wang, Ya Tu, and Jin Wang. "An Ensemble Learning Method for Wireless Multimedia Device Identification." Security and Communication Networks 2018 (October 15, 2018): 1–9. http://dx.doi.org/10.1155/2018/5264526.

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In the last decade, wireless multimedia device is widely used in many fields, which leads to efficiency improvement, reliability, security, and economic benefits in our daily life. However, with the rapid development of new technologies, the wireless multimedia data transmission security is confronted with a series of new threats and challenges. In physical layer, Radio Frequency Fingerprinting (RFF) is a unique characteristic of IoT devices themselves, which can difficultly be tampered. The wireless multimedia device identification via Radio Frequency Fingerprinting (RFF) extracted from radio signals is a physical-layer method for data transmission security. Just as people’s unique fingerprinting, different Internet of Things (IoT) devices exhibit different RFF which can be used for identification and authentication. In this paper, a wireless multimedia device identification system based on Ensemble Learning is proposed. The key technologies such as signal detection, RFF extraction, and classification model are discussed. According to the theoretical modeling and experiment validation, the reliability and the differentiability of the RFFs are evaluated and the classification results are shown under the real wireless multimedia device environments.

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Ohta, M., K. Ina, K. Kusuzaki, N. Kido, Y. Arakawa, and N. Kato. "Cloning and expression of the rfe?rff gene cluster of Escherichia coli." Molecular Microbiology 5, no. 8 (August 1991): 1853–62. http://dx.doi.org/10.1111/j.1365-2958.1991.tb00809.x.

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Morales-Ferre, Ruben, Wenbo Wang, Alejandro Sanz-Abia, and Elena-Simona Lohan. "Identifying GNSS Signals Based on Their Radio Frequency (RF) Features—A Dataset with GNSS Raw Signals Based on Roof Antennas and Spectracom Generator." Data 5, no. 1 (February 17, 2020): 18. http://dx.doi.org/10.3390/data5010018.

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This is a data descriptor paper for a set of raw GNSS signals collected via roof antennas and Spectracom simulator for general-purpose uses. We give one example of possible data use in the context of Radio Frequency Fingerprinting (RFF) studies for signal-type identification based on front-end hardware characteristics at transmitter or receiver side. Examples are given in this paper of achievable classification accuracy of six of the collected signal classes. The RFF is one of the state-of-the-art, promising methods to identify GNSS transmitters and receivers, and can find future applicability in anti-spoofing and anti-jamming solutions for example. The uses of the provided raw data are not limited to RFF studies, but can extend to uses such as testing GNSS acquisition and tracking, antenna array experiments, and so forth.

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Lombana, Nicholas F., Reuben A. Falola, Michael Scott, and Michel H. Saint-Cyr. "Epimysial Transposition Flap: A Novel Technique for Coverage of Exposed Tendon after Tissue Transfer." Journal of Reconstructive Microsurgery Open 06, no. 01 (January 2021): e51-e56. http://dx.doi.org/10.1055/s-0041-1729954.

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Abstract Background The radial forearm flap (RFF) is a versatile flap that can be used for soft-tissue coverage or as a source of vascularized bone during reconstruction. A problem that can arise after RFF harvest is tendon exposure in the donor site, which may lead to tendon injury and restriction of the hand and wrist’s range of motion. Many different methods for providing adequate tendon coverage in the donor site after RFF harvest have been reported. We present a novel technique for coverage of exposed tendon in the volar forearm with an epimysial transposition flap and a split-thickness skin graft (STSG). Methods Retrospective review of two cases: one salvage case with exposed tendon after harvesting an RFF and another with exposed volar forearm tendon after traumatic injuries. Variables of interest were post-operative STSG integration and hand/wrist range of motion. Results Both cases demonstrated 100% graft take at 5-week follow-up. No decrease in hand/wrist range of motion in the patient that could undergo testing. Conclusion We introduce two cases for coverage of exposed flexor tendon in the volar forearm with an epimysial transposition flap. This can be used as a salvage operation for coverage of exposed tendon or as an acute method of tendon coverage prior to skin grafting. In both cases, the skin graft had excellent incorporation.

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Uzundurukan, Emre, Yaser Dalveren, and Ali Kara. "A Database for the Radio Frequency Fingerprinting of Bluetooth Devices." Data 5, no. 2 (June 21, 2020): 55. http://dx.doi.org/10.3390/data5020055.

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Radio frequency fingerprinting (RFF) is a promising physical layer protection technique which can be used to defend wireless networks from malicious attacks. It is based on the use of the distinctive features of the physical waveforms (signals) transmitted from wireless devices in order to classify authorized users. The most important requirement to develop an RFF method is the existence of a precise, robust, and extensive database of the emitted signals. In this context, this paper introduces a database consisting of Bluetooth (BT) signals collected at different sampling rates from 27 different smartphones (six manufacturers with several models for each). Firstly, the data acquisition system to create the database is described in detail. Then, the two well-known methods based on transient BT signals are experimentally tested by using the provided data to check their solidity. The results show that the created database may be useful for many researchers working on the development of the RFF of BT devices.

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Chand, S., A. McCraw, R. Hutton, E. G. D. Tuddenham, and A. H. Goodall. "A Two-Site, Monoclonal Antibody-Based Immunoassay for von Willebrand Factor -Demonstration that vWF Function Resides in a Conformational Epitope." Thrombosis and Haemostasis 55, no. 03 (1986): 318–24. http://dx.doi.org/10.1055/s-0038-1661555.

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SummaryTwo monoclonal antibodies (RFF-VIII: R/l and RFF-VIII:R/ 2) which recognise the same epitope on von Willebrand factor (vWF) have been used in a simple, two-site, solid-phase immunoradiometric (IRMA) or enzyme-linked assay (ELISA) to analyse vWF in plasma from normal individuals and from patients with von Willebrand’s disease (vWD). Results obtained confirm our previous findings (using RFF-VIII :R/2 in a one-site, fluid-phase IRMA) that the MAbs detect the presence of an epitope on the vWF molecule that reflects its function. This epitope is involved in vWF binding to the GPIb protein on platelets. It is reduced in all types of vWD, including type II (or variant) vWD. It is present in normal plasma, in vWF released from normal platelets and from cultured umbilical cord vein endothelial cells. The epitope is, however, found to be reduced in serum. Studies on SDS-treated vWF prove that this GPIb-binding site is dependent on the conformation of the vWF multimers.

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Wei, Xinyuan, and Chris P. S. Larsen. "Methods to Detect Edge Effected Reductions in Fire Frequency in Simulated Forest Landscapes." ISPRS International Journal of Geo-Information 8, no. 6 (June 14, 2019): 277. http://dx.doi.org/10.3390/ijgi8060277.

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Reductions in fire frequency (RFF) are known to occur in the area adjacent to the rigid-boundary of simulated forest landscapes. Few studies, however, have removed those edge effected regions (EERs), and many others may, thus, have misinterpreted their simulated forest conditions within those unidentified edges. We developed three methods to detect and remove EERs with RFF and applied them to fire frequency maps of 2900 × 2900 grids developed using between 1000 and 1200 fire-year maps. The three methods employed different approaches: scanning, agglomeration, and division, along with the consensus of two and three of those methods. The detected EERs with RFF ranged in mean width from 5.9 to 17.3 km, and occupied 4.9 to 21.3% of the simulated landscapes. Those values are lower than the 40 km buffer width, which occupied 47.5% of the simulated landscape, used in a previous study in this area that based buffer width on length of the largest fire. The maximum width of the EER covaried with wind predominance, indicating it is not possible to prescribe a standard buffer width for all simulation studies. The three edge detection methods differ in their optimality, with the best results provided by a consensus of the three methods. We suggest that future landscape forest simulation studies should, to ensure their results near the rigid boundary are not misrepresentative, simulate an appropriately enlarged study area and then employ edge detection methods to remove the EERs with RFF.

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Lumen, N., S. Monstrey, P. Ceulemans, E. van Laecke, and P. Hoebeke. "Reconstructive Surgery for Severe Penile Inadequacy: Phalloplasty with a Free Radial Forearm Flap or a Pedicled Anterolateral Thigh Flap." Advances in Urology 2008 (2008): 1–5. http://dx.doi.org/10.1155/2008/704343.

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Objectives. Severe penile inadequacy in adolescents is rare. Phallic reconstruction to treat this devastating condition is a major challenge to the reconstructive surgeon. Phallic reconstruction using the free radial forearm flap (RFF) or the pedicled anterolateral thigh flap (ALTF) has been routinely used in female-to-male transsexuals. Recently we started to use these techniques in the treatment of severe penile inadequacy.Methods. Eleven males (age 15 to 42 years) were treated with a phallic reconstruction. The RFF is our method of choice; the ALTF is an alternative when a free flap is contraindicated or less desired by the patient. The RFF was used in 7 patients, the ALTF in 4 patients. Mean followup was 25 months (range: 4–49 months). Aesthetic and functional results were evaluated.Results. There were no complications related to the flap. Aesthetic results were judged as “good” in 9 patients and “moderate” in 2 patients. Sensitivity in the RFF was superior compared to the ALTF. Four patients developed urinary complications (stricture and/or fistula). Six patients underwent erectile implant surgery. In 2 patients the erectile implant had to be removed due to infection or erosion.Conclusion. In case of severe penile inadequacy due to whatever condition, a phalloplasty is the preferred treatment nowadays. The free radial forearm flap is still the method of choice. The anterolateral thigh flap can be a good alternative, especially when free flaps are contraindicated, but sensitivity is markedly inferior in these flaps.

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Baumgartinger, J., St Strasser, R. Starlinger, and R. Groesswang. "Technology review: RFF – membrane free backwash microfiltration." Filtration & Separation 46, no. 2 (March 2009): 13–14. http://dx.doi.org/10.1016/s0015-1882(09)70030-8.

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Colomer, Chantal. "RFF-SNCF : une réforme sous haute tension." Alternatives Économiques N° 332, no. 2 (February 10, 2014): 34. http://dx.doi.org/10.3917/ae.332.0034.

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Bosch, T., W. Samtleben, J. Thiery, H. J. Gurland, and D. Seidel. "Reverse Flux Filtration: A New Mode of Therapy Improving the Efficacy of Heparin - Induced Extracorporeal Ldl Precipitation in Hyperlipidemic Hemodialysis Patients." International Journal of Artificial Organs 16, no. 2 (February 1993): 75–85. http://dx.doi.org/10.1177/039139889301600204.

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In the steady state after a run-in phase of 3 months, the acute effects of 3 modifications of weekly heparin-induced extracorporeal LDL precipitation (HELP) were studied in 5 ESRD and 2 non-uremic hypercholesterolemic coronary patients. In ESRD patients (n=29 sessions), HELP reduced LDL-cholesterol (LDL-C) (56 ± 7%) and fibrinogen (FIB) (54 ± 10%) by a similar percentage as compared to non-uremic controls (60 ± 4% and 61 ± 3%, resp.; n=5). In order to eliminate the need for extra HELP sessions in addition to the normal dialysis regimen, newly developed hardware was then used to perform combined synchronous HELP/HD (n=12). However, premature precipitate filter plugging probably due to hyperfibrinogenemia in ESRD patients, accentuated by ultrafiltration (UF), decreased the corresponding reductions to 26 ± 9% (LDL-C) and 34 ± 11% (FIB). Therefore, the procedure was modified by reversing the filtrate flux through the precipitate filter membrane after 900 ml of treated plasma (“reverse flux filtration”, RFF; n=11). Thus, in RFF-HELP/HD the LDL/FIB/heparin coprecipitate was deposited on both filter membrane sides which caused a significant enhancement of the filter capacity and improved reductions to 46 ± 14% for LDL-C and 51 ± 15% for FIB. Elution of the precipitate from the precipitate filter after the sessions showed that RFF-HELP/HD had trapped 1733 ± 238 mg LDL-C and 8108 ± 1876 mg FIB in ESRD patients, while HELP eliminated 1890 ± 333 mg LDL-C and only 3663 ± 369 mg FIB in non-uremics. Filter precipitate recoveries (relative to the mass removed from the patient plasma pool) amounted to 97 ± 18% for LDL-C and 158 ± 67% for FIB in the ESRD group treated by RFF-HELP/HD vs. 70 and 76% in the non-uremic HELP group. Probably, passive transport of lipoproteins and FIB from the interstitium into the vascular space caused repletion of this compartment during HELP/HD where an UF induced solvent drag is effective. In summary, the new RFF-HELP/HD procedure effectively reduced LDL-C and FIB in ESRD patients who could not be adequately treated by the conventional HELP/HD system.

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Hoffman, Ryan D., Denise M. Danos, Samuel J. Lin, Frank H. Lau, and Peter S. Kim. "Prevalence of Accessory Branches and Other Anatomical Variations in the Radial Artery Encountered during Radial Forearm Flap Harvest: A Systematic Review and Meta-analysis." Journal of Reconstructive Microsurgery 36, no. 09 (June 24, 2020): 651–59. http://dx.doi.org/10.1055/s-0040-1713600.

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Abstract Background Harvest of the radial forearm flap (RFF) for reconstructive surgery is proceeded by the Allen test to assess for adequate contralateral perfusion of the hand, yet the Allen test may fail to detect anatomical variations in the radial artery such as aberrant branching. Therefore, the goal of this study was to systematically review the literature regarding anatomical abnormalities of the radial artery that can affect flap harvest and to perform a meta-analysis to estimate the prevalence of such abnormalities. Methods A systematic review of the literature was conducted using five online databases to identify all instances of radial artery anatomical variations. Abstracts were reviewed and categorized into either (1) large cohort studies of anatomical variations identified by angiogram or (2) case reports specifically mentioning anomalous or accessory branches of the radial artery. Data from the large cohort studies were included in a random effect meta-analysis to estimate the prevalence of such variations. Results Eighteen angiogram cohort studies containing a total of 18,115 patients were included in the meta-analysis. Accessory branches were the least common anatomical variant reported, with an estimated average prevalence of 0.5%. Prevalence estimates for more common anatomical variants, including radial artery loops (0.9%), stenosis (1.3%), hypoplasia (1.9%), tortuosity (4.3%), and abnormal origin (5.6%), were also calculated. Thirteen case reports detailing anomalous branches of the radial artery were identified, seven of which involved accessory branches encountered during RFF harvest with no incidence of flap loss. Conclusion Radial artery accessory branches are exceedingly rare, but the prevalence of other anatomical variations that can affect harvest of the RFF warrants consideration. We recommend surgeons consider comprehensive screening prior to RFF harvest to avoid intraoperative discovery of anatomical variants and suggest a low threshold for repeat perfusion testing intraoperatively if radial artery accessory branches are encountered.

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Aghnaiya, Alghannai, Yaser Dalveren, and Ali Kara. "On the Performance of Variational Mode Decomposition-Based Radio Frequency Fingerprinting of Bluetooth Devices." Sensors 20, no. 6 (March 19, 2020): 1704. http://dx.doi.org/10.3390/s20061704.

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Radio frequency fingerprinting (RFF) is one of the communication network’s security techniques based on the identification of the unique features of RF transient signals. However, extracting these features could be burdensome, due to the nonstationary nature of transient signals. This may then adversely affect the accuracy of the identification of devices. Recently, it has been shown that the use of variational mode decomposition (VMD) in extracting features from Bluetooth (BT) transient signals offers an efficient way to improve the classification accuracy. To do this, VMD has been used to decompose transient signals into a series of band-limited modes, and higher order statistical (HOS) features are extracted from reconstructed transient signals. In this study, the performance bounds of VMD in RFF implementation are scrutinized. Firstly, HOS features are extracted from the band-limited modes, and then from the reconstructed transient signals directly. Performance comparison due to both HOS feature sets is presented. Moreover, the lower SNR bound within which the VMD can achieve acceptable accuracy in the classification of BT devices is determined. The approach has been tested experimentally with BT devices by employing a Linear Support Vector Machine (LSVM) classifier. According to the classification results, a higher classification performance is achieved (~4% higher) at lower SNR levels (−5–5 dB) when HOS features are extracted from band-limited modes in the implementation of VMD in RFF of BT devices.

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Benanti, Elisa, Marta Starnoni, Antonio Spaggiari, Massimo Pinelli, and Giorgio De Santis. "Objective Selection Criteria between ALT and Radial Forearm Flap in Oral Soft Tissues Reconstruction." Indian Journal of Plastic Surgery 52, no. 02 (May 2019): 166–70. http://dx.doi.org/10.1055/s-0039-1693504.

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AbstractDifferent locoregional and free flaps were described for oral soft tissues reconstruction after oncological resections; however, free flaps remain the first choice. Among free flaps, the radial forearm flap (RFF) and the anterolateral thigh perforator flap (ALT) are preferred the most. The lack of standardization of the flap choice leaves the selection to the surgeon's experience. The purpose of our observational study is to provide an algorithm to support the flap choice for the reconstruction of oral soft tissues. Sixty patients with squamous cell carcinoma of oral soft tissues were enrolled in our study. All the patients underwent preoperative magnetic resonance imaging (MRI) to measure the three-dimensional size of the tumor. During the follow-up, the patients were evaluated by using the University of Washington-Quality of Life Questionnaire. The questionnaire score was better for small tumors and worse for large tumors in both functional and relational fields. We observed that most of the overlapping results were obtained for small defects and the choice of RFF, as well as for large defects and the use of ALT. We observed that in the preoperative time, it is possible to select which flap between radial forearm and ALT is more appropriate for oral soft tissues defects reconstruction, according to the size of the tumor evaluated by MRI. We propose a decisional algorithm that suggests the type of flap to use between ALT and RFF.

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Riddle, A. "Microwave and RFf design of wireless systems [Book Review]." IEEE Microwave Magazine 3, no. 1 (March 2002): 100. http://dx.doi.org/10.1109/mmw.2002.990701.

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Darmstadter, Joel. "John Tilton and RFF: a case of mutual admiration." Mineral Economics 33, no. 1-2 (April 24, 2019): 5–7. http://dx.doi.org/10.1007/s13563-019-00179-2.

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Maqsood, Arfa, and Rafia Shafi. "A Soft-Drink Experiment using Replicated Full Factorial (RFF) Design." International Journal of Computer Applications 171, no. 1 (August 17, 2017): 25–30. http://dx.doi.org/10.5120/ijca2017914957.

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Leonard, Ann E. "Briefly Noted: Climate Change Economics and Policy: An RFF Anthology." Journal of Environment & Development 11, no. 1 (March 2002): 120–21. http://dx.doi.org/10.1177/107049650201100110.

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Sfeir, Elie, Rangeet Mitra, Georges Kaddoum, and Vimal Bhatia. "RFF Based Detection for SCMA in Presence of PA Nonlinearity." IEEE Communications Letters 24, no. 11 (November 2020): 2604–8. http://dx.doi.org/10.1109/lcomm.2020.3010698.

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Sharma, Ameya, Vivek Puri, Pradeep Kumar, Inderbir Singh, and Kampanart Huanbutta. "Development and Evaluation of Rifampicin Loaded Alginate–Gelatin Biocomposite Microfibers." Polymers 13, no. 9 (May 8, 2021): 1514. http://dx.doi.org/10.3390/polym13091514.

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Various systematic phases such as inflammation, tissue proliferation, and phases of remodeling characterize the process of wound healing. The natural matrix system is suggested to maintain and escalate these phases, and for that, microfibers were fabricated employing naturally occurring polymers (biopolymers) such as sodium alginate, gelatin and xanthan gum, and reinforcing material such as nanoclay was selected. The fabrication of fibers was executed with the aid of extrusion-gelation method. Rifampicin, an antibiotic, has been incorporated into a biopolymeric solution. RF1, RF2, RF3, RF4 and RF5 were coded as various formulation batches of microfibers. The microfibers were further characterized by different techniques such as SEM, DSC, XRD, and FTIR. Mechanical properties and physical evaluations such as entrapment efficiency, water uptake and in vitro release were also carried out to explain the comparative understanding of the formulation developed. The antimicrobial activity and whole blood clotting of fabricated fibers were additionally executed, hence they showed significant results, having excellent antimicrobial properties; they could be prominent carriers for wound healing applications.

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Musazura, W., A. O. Odindo, I. B. Bame, and E. H. Tesfamariam. "Effect of irrigation with anaerobic baffled reactor effluent on Swiss chard (Beta vulgaris cicla.) yield, nutrient uptake and leaching." Journal of Water Reuse and Desalination 5, no. 4 (April 15, 2015): 592–609. http://dx.doi.org/10.2166/wrd.2015.011.

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The disposal of treated wastewater from an anaerobic baffled reactor (ABR) effluent into water bodies can cause pollution. Treated wastewater management through irrigation of crops has the potential of increasing crop production through nutrient uptake while reducing the risks of environmental pollution. However, this study aimed to investigate the effect of irrigation with ABR effluent on Swiss chard yield, nutrient (N and P) uptake and leaching. Field experiments were done over three seasons at Newlands, Durban, South Africa. The experiments were laid out in a randomised complete block design with three treatments: ABR effluent irrigation (ABR), tap water irrigation with fertiliser (TWF) and rain-fed with fertiliser (RFF). Data were collected on nutrient (N and P) leaching at 30 and 50 cm depths, crop growth, soil chemical properties and nutrient uptake. Effects of irrigation with ABR effluent on soil chemical properties, Swiss chard growth, plant nutrient uptake and leaching were comparable to TWF and RFF treatments. This implies that irrigating crops with ABR effluent is a potential method for wastewater management in a manner that will not cause environmental pollution while benefiting peri-urban farmers.

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Vega Rovira, Yosiat A., Angélica Rodríguez, Rosa Villarreal, and Juan A. Bernal Vega. "INTENSIDAD DE LA HERBIVORÍA EN DOS TIPOS DE SUELO EN LA RESERVA FORESTAL FORTUNA." Tecnociencia 22, no. 2 (July 2, 2020): 5–26. http://dx.doi.org/10.48204/j.tecno.v22n2a1.

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La herbivoría es una de las interacciones de mayor impacto en los trópicos debido a que la vegetación está expuesta a una mayor abundancia y riqueza de folívoros. Se determinó el nivel de herbivoría, la abundancia y diversidad de folívoros, y su relación con el tipo de suelo en la Reserva Forestal Fortuna (RFF). Se evaluó la herbivoría de febrero a septiembre de 2014 en dos parcelas (Honda A y Pinola) en cinco especies vegetales: Cupania seemannii, Faramea multiflora, Guarea glabra, Inga alba y Osteophloeum platyspermum. Se obtuvieron 170 especímenes pertenecientes a nueve órdenes, 38 familias, 29 géneros y 64 morfoespecies pertenecientes a las clases Insecta, Malacostraca y Gastropoda. El índice de Shannon-Weaver indicó una alta diversidad en la RFF (3.47 para Honda A y 3.67 para Pinola). Honda A presentó14.6 % de daño foliar y un índice de herbivoría de 2.05; mientras que Pinola fue 12.4 % y un índice de 1.96. Los porcentajes de herbivoría registrados en este estudio, se mantuvieron dentro del intervalo de daño para bosques tropicales que va de 12 %-40 %, pero no sigue el patrón teórico fundamentado en la disponibilidad de nutrientes en el suelo.

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Kumari, Priyanka, and Sushil Kumar. "Estimation of Design Flood for Rivers of Saurashtra Region Contributing into the Gulf of Khambhat." Current World Environment 11, no. 3 (December 25, 2016): 869–82. http://dx.doi.org/10.12944/cwe.11.3.23.

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Design flood has been estimated for rivers of Saurashtra region contributing into the Gulf of Khambhat using deterministic as well as statistical approach for planning, design and management of hydraulic structures. By comparing the results obtained by these approaches, one can easily estimate the flow rate or peak discharge to a given design return period and can establish the suitability of approach for this study area. Nine river basins with 20 dams of Saurashtra region were analyzed in this study. Though Saurashtra is one of the most water scarce regions of India yet it suffers from the flooding problem, as the numbers of rainy days are very less and the rainfall intensity is very high. Due to being a regulated basin, dam wise study was preferred. Deterministic approach was carried out using synthetic unit hydrograph (SUH) and regional flood formulae (RFF) methods for subzone-3a provided in Central Water Commission (CWC) report, 2001. Statistical approach was carried out using Rainfall frequency analysis employingGumbel’s EV1distribution. As there is no spill by these hydraulic structures and the annual flood data for the nine river sites are heavily affected by the storage dams in the upstream. Hence these data violate the basic principle of virgin flow. Hence the analysis of these data was not attempted further. The main objective of study was to carry out the rainfall frequency analysis for these river basins to get 24 hour rainfall for a return period of 25, 50 and 100 years for an individual basin instead of using the value obtained by iso-pluvial map to estimate the design flood. The overall results reveals that due to construction of number of dams in 9 river basins, design flood estimation on each dam by using deterministic approach is more feasible.Revised design floods using SUH and RFF method on the basis of estimated rainfall indicates over-estimated and under-estimated design floods. Since the percentage difference is very less between revised SUH and revised RFF method. So, for safety purpose one with higher value should be used.

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Mirsam, Hishar, Masluki Masluki, and Mutmainnah Mutmainnah. "Isolasi dan Seleksi Cendawan Rhizosfer dan Endofit asal Tanaman Kelor sebagai Agens Penginduksi Perkecambahan pada Benih Padi." AGROSAINSTEK: Jurnal Ilmu dan Teknologi Pertanian 5, no. 1 (May 28, 2021): 34–43. http://dx.doi.org/10.33019/agrosainstek.v5i1.227.

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Cendawan rhizosfer dan endofit merupakan jenis mikroba fungsional yang mampu memproduksi metabolit sekunder yang dapat memengaruhi pertumbuhan tanaman baik secara langsung atau tidak langsung. Penelitian ini bertujuan mengisolasi dan menguji kemampuan cendawan rhizosfer dan endofit asal tanaman kelor terhadap viabilitas dan vigor kecambah benih padi. Eksplorasi cendawan dilakukan terhadap sampel tanah di bagian rhizosfer serta jaringan batang dan daun tanaman kelor sehat. Isolasi cendawan dari tanah bagian rhizosfer dilakukan dengan teknik pengenceran 10-2 dan 10-3, sedangkan cendawan endofit dilakukan pada jaringan daun dan batang tanamn kelor, kemudian dibiakkan pada media medium potato dextrose agar (PDA). Uji patogenisitas cendawan dan pengaruhnya terhadap perkecambahan benih padi secara in-vitro dengan metode blotter test, yaitu dengan cara menumbuhkan benih padi sebanyak 25 butir pada isolat cendawan berumur 7 hari. Sebanyak sembilan belas isolat cendawan berhasil diisolasi dan dikoleksi dari berbagai bagian tanaman kelor. Pengamatan patogenisitas menunjukkan terdapat lima isolat cendawan yang berpotensi sebagai patogen, yaitu isolat RF2, RF5, RF6, RF8, dan EDF6. Sebanyak empat isolat cendawan yang telah diuji konsisten memberikan pengaruh positif terhadap viabilitas dan vigor benih benih dengan nilai ≥90% yaitu isolate RF4, EDF1, EDF2, dan EDFbt3

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Xie, Renjie, Wei Xu, Yanzhi Chen, Jiabao Yu, Aiqun Hu, Derrick Wing Kwan Ng, and A. Lee Swindlehurst. "A Generalizable Model-and-Data Driven Approach for Open-Set RFF Authentication." IEEE Transactions on Information Forensics and Security 16 (2021): 4435–50. http://dx.doi.org/10.1109/tifs.2021.3106166.

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Meier-Dieter, U., K. Barr, R. Starman, L. Hatch, and P. D. Rick. "Nucleotide sequence of the Escherichia coli rfe gene involved in the synthesis of enterobacterial common antigen. Molecular cloning of the rfe-rff gene cluster." Journal of Biological Chemistry 267, no. 2 (January 1992): 746–53. http://dx.doi.org/10.1016/s0021-9258(18)48347-0.

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Yang, Feikun, Ru Hao, Barbara Kessler, Gottfried Brem, Eckhard Wolf, and Valeri Zakhartchenko. "Rabbit somatic cell cloning: effects of donor cell type, histone acetylation status and chimeric embryo complementation." Reproduction 133, no. 1 (January 2007): 219–30. http://dx.doi.org/10.1530/rep.1.01206.

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The epigenetic status of a donor nucleus has an important effect on the developmental potential of embryos produced by somatic cell nuclear transfer (SCNT). In this study, we transferred cultured rabbit cumulus cells (RCC) and fetal fibroblasts (RFF) from genetically marked rabbits (Alicia/Basilea) into metaphase II oocytes and analyzed the levels of histone H3-lysine 9-lysine 14 acetylation (acH3K9/14) in donor cells and cloned embryos. We also assessed the correlation between the histone acetylation status of donor cells and cloned embryos and their developmental potential. To test whether alteration of the histone acetylation status affects development of cloned embryos, we treated donor cells with sodium butyrate (NaBu), a histone deacetylase inhibitor. Further, we tried to improve cloning efficiency by chimeric complementation of cloned embryos with blastomeres fromin vivofertilized or parthenogenetic embryos. The levels of acH3K9/14 were higher in RCCs than in RFFs (P<0.05). Although the type of donor cells did not affect development to blastocyst, after transfer into recipients, RCC cloned embryos induced a higher initial pregnancy rate as compared to RFF cloned embryos (40 vs 20%). However, almost all pregnancies with either type of cloned embryos were lost by the middle of gestation and only one fully developed, live RCC-derived rabbit was obtained. Treatment of RFFs with NaBu significantly increased the level of acH3K9/14 and the proportion of nuclear transfer embryos developing to blastocyst (49 vs 33% with non-treated RFF,P<0.05). The distribution of acH3K9/14 in either group of cloned embryos did not resemble that inin vivofertilized embryos suggesting that reprogramming of this epigenetic mark is aberrant in cloned rabbit embryos and cannot be corrected by treatment of donor cells with NaBu. Aggregation of embryos cloned from NaBu-treated RFFs with blastomeres fromin vivoderived embryos improved development to blastocyst, but no cloned offspring were obtained. Two live cloned rabbits were produced from this donor cell type only after aggregation of cloned embryos with a parthenogenetic blastomere. Our study demonstrates that the levels of histone acetylation in donor cells and cloned embryos correlate with their developmental potential and may be a useful epigenetic mark to predict efficiency of SCNT in rabbits.

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Murdock, Paul J., Barry J. Woodhams, Kathy B. Matthews, K. John Pasi, and Alison H. Goodall. "von Willebrand Factor Activity Detected in a Monoclonal Antibody-based ELISA: an Alternative to the Ristocetin Cofactor Platelet Agglutination Assay for Diagnostic Use." Thrombosis and Haemostasis 78, no. 04 (1997): 1272–77. http://dx.doi.org/10.1055/s-0038-1657727.

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SummaryThe monoclonal antibody RFF-VIII:R/1 recognises an epitope on von Willebrand factor involved in its interaction with GPIbα. A two-site, solid phase ELISA has been established using RFF-VIII:R/1 as the solid-phase, capture antibody and an enzyme-conjugated, polyclonal antibody to human VWF, which provides an assay for VWF functional activity with a detection limit of 0.5 U/dl VWF and an interassay %CV<10. Plasma from 192 VWD patients (48 studied retrospectively; 144 prospectively) showed VWF levels of <50 U/dl in type 1 patients (n = 156), <25 U/dl in type 2A (n = 26) and <35 U/dl in type 2B (n = 8) which, in type 1 and 2A patients, correlated with RiCoF activity (r >0.82). In plasma from patients with type 1 VWD values of VWF in the Mab-based ELISA were similar to levels of VWF:Ag measured in a polyclonal antibody-based ELISA (r >0.87) but were significantly lower than VWF:Ag in type 2A and 2B plasmas (p <0.0005), allowing discrimination of variant VWD. The Mab-based ELISA has advantages of sensitivity and reproducibility over the RiCoF assay to measure VWF activity and can be used to analyse stored samples. In conjunction with an ELISA for VWF:Ag and VWF multimer analysis, it provides a reliable method, for the laboratory diagnosis of VWD.

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Kelkar, Kshitija, Meghan E. Gray, Alfonso Aragón-Salamanca, Gregory Rudnick, Yara L. Jaffé, Pascale Jablonka, John Moustakas, and Bo Milvang-Jensen. "The time delay between star formation quenching and morphological transformation of galaxies in clusters: a phase–space view of EDisCS." Monthly Notices of the Royal Astronomical Society 486, no. 1 (March 28, 2019): 868–84. http://dx.doi.org/10.1093/mnras/stz905.

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Abstract We explore the possible effect of cluster environments on the structure and star formation histories of galaxies by analysing the projected phase–space (PPS) of intermediate-redshift clusters (0.4 ≤ z ≤ 0.8). HST I−band imaging data from the ESO Distant Cluster Survey (EDisCS) allow us to measure deviations of the galaxies’ light distributions from symmetric and smooth profiles using two parameters, Ares (‘asymmetry’) and RFF (residual flux fraction or ‘roughness’). Combining these structural parameters with age-sensitive spectral indicators ($H_{\delta \rm {A}}$, $H_{\gamma \rm {A}}$, and Dn4000), we establish that in all environments younger star-forming galaxies of all morphologies are ‘rougher’ and more asymmetric than older, more quiescent ones. Combining a subset of the EDisCS clusters, we construct a stacked PPS diagram and find a significant correlation between the position of the galaxies on the PPS and their stellar ages, irrespective of their morphology. We also observe an increasing fraction of galaxies with older stellar populations towards the cluster core, while the galaxies’ structural parameters (Ares and RFF) do not seem to segregate strongly with PPS. These results may imply that, under the possible influence of their immediate cluster environment, galaxies have their star formation suppressed earlier, while their structural transformation happens on a longer time-scale as they accumulate and age in the cluster cores.

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Zaki, Basim M., Khalid M. El-Sherbiny, Abdel Rahman Abdel Aal, and Hazem M. Aly. "Modifications of the free radial forearm flap (RFF) used in total penile reconstruction." Ain Shams Journal of Surgery 6, no. 1 (January 1, 2010): 63–69. http://dx.doi.org/10.21608/asjs.2010.177480.

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Arezzo, Francesca, Daniele La Forgia, Vincenzo Venerito, Marco Moschetta, Alberto Stefano Tagliafico, Claudio Lombardi, Vera Loizzi, Ettore Cicinelli, and Gennaro Cormio. "A Machine Learning Tool to Predict the Response to Neoadjuvant Chemotherapy in Patients with Locally Advanced Cervical Cancer." Applied Sciences 11, no. 2 (January 17, 2021): 823. http://dx.doi.org/10.3390/app11020823.

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Despite several studies having identified factors associated with successful treatment outcomes in locally advanced cervical cancer, there is the lack of accurate predictive modeling for progression-free survival (PFS) in patients who undergo radical hysterectomy after neoadjuvant chemotherapy (NACT). Here we investigated whether machine learning (ML) may have the potential to provide a tool to predict neoadjuvant treatment response as PFS. In this retrospective observational study, we analyzed patients with locally advanced cervical cancer (FIGO stages IB2, IB3, IIA1, IIA2, IIB, and IIIC1) who were followed in a tertiary center from 2010 to 2018. Demographic and clinical characteristics were collected at either treatment baseline or at 24-month follow-up. Furthermore, we recorded data about magnetic resonance imaging (MRI) examinations and post-surgery histopathology. Proper feature selection was used to determine an attribute core set. Three different machine learning algorithms, namely Logistic Regression (LR), Random Forest (RFF), and K-nearest neighbors (KNN), were then trained and validated with 10-fold cross-validation to predict 24-month PFS. Our analysis included n. 92 patients. The attribute core set used to train machine learning algorithms included the presence/absence of fornix infiltration at pre-treatment MRI as well as of either parametrium invasion and lymph nodes involvement at post-surgery histopathology. RFF showed the best performance (accuracy 82.4%, precision 83.4%, recall 96.2%, area under receiver operating characteristic curve (AUROC) 0.82). We developed an accurate ML model to predict 24-month PFS.

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Zakhartchenko, V., F. Yang, R. Hao, and E. Wolf. "102 RABBIT CLONING: HISTONE ACETYLATION STATUS OF DONOR CELLS AND CLONED EMBRYOS." Reproduction, Fertility and Development 19, no. 1 (2007): 168. http://dx.doi.org/10.1071/rdv19n1ab102.

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Epigenetic status of the genome of a donor nucleus is likely to be associated with the developmental potential of cloned embryos produced by somatic cell nuclear transfer (SCNT). Prevention of epigenetic errors by manipulation of the epigenetic status of donor cells is expected to result in improvement of cloning efficiency. In this study, we transferred cultured rabbit cumulus cells (RCC) and fetal fibroblasts (RFF) from genetically marked rabbits (Ali/Bas) into metaphase II (MII) oocytes and analyzed the levels of histone H3K9 acetylation in donor cells and cloned embryos. We also assessed the correlation between the histone acetylation status of donor cells and cloned embryos and their developmental potential. To test whether alteration of the histone acetylation status affects development of cloned embryos, we treated donor cells with sodium butyrate (NaBu), a histone deacetylase inhibitor. Further, we tried to improve cloning efficiency by chimeric complementation of cloned embryos with one or two blastomeres from in vitro-fertilized or parthenogenetic embryos. Histone acetylation in donor cells and cloned embryos was detected by anti-acH3K9 antibody using Western immunoblot analysis or immunochemistry, respectively. Data were analyzed by chi-square (developmental rates) or Student-Newman-Keuls (histone acetylation) test. The levels of acetylated histone H3K9 were higher in RCCs than in RFFs (P < 0.05). Although the type of donor cells did not affect development to blastocyst, after transfer into recipients, RCC-cloned embryos induced a higher initial pregnancy rate as compared to RFF-cloned embryos (40% vs. 20%; P < 0.05). However, almost all pregnancies with either type of cloned embryos were lost by the middle of gestation and only one fully developed; a live RCC-derived rabbit was obtained. Treatment of RFFs with NaBu significantly (P < 0.05) increased the level of histone H3K9/14 acetylation and the proportion of nuclear transfer embryos developing to blastocyst (49% vs. 33% with non-treated RFF; P < 0.05). The distribution of signals for acH3K9 in either group of cloned embryos did not resemble that in in vivo-fertilized embryos, suggesting that reprogramming of this epigenetic mark is aberrant in cloned rabbit embryos and cannot be corrected by treatment of donor cells with NaBu. Aggregation of embryos cloned from NaBu-treated RFFs with blastomeres from in vivo-derived embryos improved development to blastocyst, but no cloned offspring were obtained. Two live cloned rabbits were produced from this donor cell type only after aggregation of cloned embryos with a parthenogenetic blastomere. Our study demonstrates that the levels of histone acetylation in donor cells and cloned embryos correlate with their developmental potential and can be a useful epigenetic mark to predict efficiency of SCNT rabbits. This work was supported by the Bayerische Forschungsstiftung and by Therapeutic Human Polyclonals, Inc.

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Kunisaki, Yuya, Daniel Lucas, and Paul S. Frenette. "Circadian Expression of Endothelial Selectins, Regulated by the Sympathetic Nervous System, Controls Peripheral Leukocyte Homeostasis." Blood 112, no. 11 (November 16, 2008): 548. http://dx.doi.org/10.1182/blood.v112.11.548.548.

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Abstract We have recently shown that hematopoietic stem cells (HSCs) are released into peripheral blood in a circadian manner, controlled by the sympathetic nervous system (SNS) through the regulation of CXCL12 levels in the bone marrow (BM) (Mendez-Ferrer et. al. Nature2008;452:442). In addition to the oscillations in circulating HSC numbers, we have also observed circadian fluctuations in the numbers of blood leukocytes in mice maintained on a standard 12h light - 12h dark cycle. Systemic leukocyte counts (4129 ± 521/μl (12 pm) vs 2000 ± 233/μl (8 pm); p=0.003) and their subsets, neutrophils (2762 ± 118 vs 732 ± 45/μl; p=0.02) and lymphocytes (5997 ± 151 vs 1867 ± 661/μl; p=0.03), were significantly reduced at night compared to the morning. We hypothesized that peripheral leukocyte counts are regulated by their interactions with endothelial cells in the BM microcirculation. To test this hypothesis we analyzed the constitutive interactions of leukocytes with BM microvessels using intravital microscopy to evaluate whether the trafficking of leukocytes in the BM microvasculature is also subjected to circadian regulation. We found that the absolute number of rolling leukocytes (18.0 ± 0.2 (12 pm) vs 31.1 ± 3.5 (8 pm) x103/mm2;p=0.004) and the rolling flux fraction (RFF, i.e. rolling/systemic leukocyte counts)(6.5 ± 0.6 vs 20.7 ± 3.1 %; p=0.0001) were increased three-fold at night, inversely correlating with the number of circulating leukocytes. Adoptive transfer experiments of fluorescently labeled BM leukocytes also revealed a two-fold increase in the number of recruited adherent leukocytes at night compared to when cells were injected in the morning (0.97 ± 0.17 (12 pm) vs 2.54 ± 0.53 (8 pm)/vessel area (μm2);p=0.007). Flow cytometry analyses revealed that the majority of these recruited cells were Mac-1+/Gr-1+ myeloid cells. This suggests that the capacity of the BM to recruit leukocytes fluctuates over the course of a day. Moreover, adoptively transferred cells formed clusters at specific sites in the BM at night. To investigate the mechanisms, we first subjected mice lacking both endothelial selectins (P-and E-selectins) to the same experimental protocols. Double deficient mice did not exhibit circadian variations in PB (9725 ± 1185/μl (12 pm) vs 8271 ± 1394/μl (8 pm); p=0.50) or BM (RFF 0.28 ± 0.05 vs 0.34 ± 0.05 %; p=0.48), and did not show clusters of adoptively transferred cells in the BM. To investigate the role of the SNS, we sympathectomized mice with 6-hydroxydopamine. Chemical sympathectomy significantly reduced the circadian differences of leukocyte rolling on BM endothelium (RFF 7.8 ± 1.1% (12 pm) vs 14.9 ± 2.8% (8 pm); p=0.01) and leukocyte numbers in PB (2750 ± 322 vs 2225 ± 363/μl; p=0.32). In addition, the number of adherent adoptively transferred cells in the BM did not show significant fluctuation (1.66 ± 0.26 vs 1.54 ± 0.20/vessel area(μm2);p=0.72). These results suggest that the process of homing/cluster formation is dependent on constitutive, oscillatory expression of P- and/or E-selectins and regulated by the SNS.

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Gomme, Joe. "Book review: Taming the Anarchy: Groundwater Governance in South Asia, by Tushaar Shah (RFF Press, 2008)." Hydrogeology Journal 19, no. 2 (January 4, 2011): 505–6. http://dx.doi.org/10.1007/s10040-010-0686-x.

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Dill, Carren L., Roger P. Wise, and Patrick S. Schnable. "Rf8 and Rf* Mediate Unique T-urf13-Transcript Accumulation, Revealing a Conserved Motif Associated With RNA Processing and Restoration of Pollen Fertility in T-Cytoplasm Maize." Genetics 147, no. 3 (November 1, 1997): 1367–79. http://dx.doi.org/10.1093/genetics/147.3.1367.

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Rf8 is a newly described nuclear gene that can substitute for Rf1 to partially restore pollen fertility to male-sterile, T-cytoplasm maize. Families segregating for Rf8 were used to investigate the mechanism of this fertility restoration and to compare it to the restoration conditioned by Rf1. Although Rf8 is unlinked to the rf1 locus, it also alters T-urf13 mitochondrial transcript accumulation and reduces the accumulation of the URF13 protein. Like the 1.6- and 0.6-kilobase (kb) T-urf13 transcripts that accumulate in T-cytoplasm plants carrying Rf1, 1.42- and 0.42-kb transcripts accumulate in plants that are partially restored by Rf8. A survey of T-cytoplasm maize lines, inbreds, and F1 hybrids by mitochondrial RNA gel blot analyses revealed that Rf8, is rare in maize germplasm. These surveys revealed the presence of another rare, weak restorer factor, Rf*, which is uniquely associated with the accumulation of 1.4- and 0.4-kb T-urf13 transcripts. Primer extension analyses position the 5′ termini of the 1.42/0.42-kb and 1.4/0.4-kb transcripts at +137 and +159 nucleotides, respectively, 3′ of the AUG initiation codon of the T-urf13 reading frame. The conserved motif, 5′-CNACNNU-3′, overlaps the 5′ termini of the Rf1-, Rf8-, and Rf*-associated transcripts and the 380 nucleotide, Rf3-associated orf107 transcript from cytoplasmic male sterility sorghum. These results demonstrate that multiple unlinked, nuclear genes can have similar but distinct effects on the expression of the unique T-urf13 mitochondrial coding sequence to restore pollen fertility to T-cytoplasm maize.

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Quintero Coronel, Daniel Andrés, Yuhan Arley Lenis Rodas, and Lesme Antonio Corredor Martínez. "Desarrollo de un modelo de gasificación en equilibrio químico para evaluar el potencial energético del cuesco en plantas extractoras de aceite de palma en Colombia." INGE CUC 14, no. 2 (December 3, 2018): 62–70. http://dx.doi.org/10.17981/ingecuc.14.2.2018.06.

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Introducción− En las industrias de extracción de aceite de palma, por cada 10 ton de racimos de fruto fresco (RFF) procesados, se producen cerca de 3700 kg de residuos con Poder Calorífico Inferior (PCI) de alrededor de 18 MJ/kg. Estos residuos, compuestos principalmente por racimos de frutos vacíos, fibra y cuesco podrían ser utilizados para generación de electricidad o vapor supliendo de manera parcial o total la demanda de energía de las empresas del sector. De estos residuos, el que mejor se adapta para generación de electricidad a partir de biomasa, en rangos menores a 2MW, es el cuesco, el cual puede ser utilizado en sistemas de gasificación de lecho fijo acoplados a motor generador. Objetivo− Evaluar el potencial energético del cuesco de palma de aceite para la generación de electricidad utilizando gasificación en lecho fijo acoplada a motor generador. Metodología− Se desarrolló un modelo de gasificación en equilibrio químico que permite estimar la composición de gases y, por tanto, el potencial energético de los residuos de cuesco de palma. Resultados- El modelo permite analizar variaciones en el proceso debidas a cambios en agente gasificante (AG), composición y contenido de humedad de la biomasa. Los resultados son validados utilizando información reportada en la literatura. El modelo es utilizado para analizar el potencial energético de los residuos de una planta extractora típica de 10000 ton RFF/mes. Conclusiones− Se estima que por cada 22 kg/h de cuesco se producen aproximadamente 70 kg/h de gas con composición promedio de 12,5 % H2, 21,8 % CO, 9,5 % CO2, 56 % N2 y trazas de CH4 c on p oder c alorífico i nferior ( PCI) c ercano a 4 ,1 M J/Nm3. Lo anterior, cuando el proceso opera con una relación de equivalencia (ER) de 0,33 y humedad de biomasa de 15 % w.t. Así, utilizando el gas como combustible para un conjunto motorgenerador, la demanda eléctrica de una planta extractora de aceite puede ser suplida en su totalidad, empleando menos del 85 % del cuesco resultante del proceso.

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de Guzman, Allan B., Jan Michael G. Garcia, Juan Paulo S. P. Garcia, Monica B. Garcia, Ross T. German, Martha Sabrina C. Gerong, and Almira Joy B. Grajo. "A Multinomial Regression Model of Risk for Falls (RFF) Factors Among Filipino Elderly in a Community Setting." Educational Gerontology 39, no. 9 (September 2013): 669–83. http://dx.doi.org/10.1080/03601277.2012.661338.

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Wang, Xin-Kuan, Gui-Bao Wang, Jianke Jia, and Chao-Jun Huang. "Synthesis of Uniformly Excited Concentric Ring Arrays by the Strategy of Partial Density Tapering and the Algorithm of Differential Evolution." International Journal of Antennas and Propagation 2020 (October 10, 2020): 1–7. http://dx.doi.org/10.1155/2020/5495846.

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A new strategy of density tapering called the partial density tapering (PDT) accompanied with the algorithm of differential evolution (DE) is proposed to suppress the peak sidelobe level (PSL) of uniform excited concentric ring arrays (UECRA) with isotropic elements. Through performing the PDT, a sound starting solution for DE can be generated. Then, the ring filling factor (RFF) is introduced so that the optimization of the number of elements can be transformed into the optimization of RFFs within the tapered thresholds, and thereby the real coding can be directly used with respect to the consideration of parallel encoding strategy. Finally, the UECRA featuring improved PSL performance can be obtained by limited runs of conventional DE. Several numerical instances for UECRA, with aperture sizes ranging from small to large scale, confirmed the outperformance of the proposed method.

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Marolda, C. L., and M. A. Valvano. "Genetic analysis of the dTDP-rhamnose biosynthesis region of the Escherichia coli VW187 (O7:K1) rfb gene cluster: identification of functional homologs of rfbB and rfbA in the rff cluster and correct location of the rffE gene." Journal of bacteriology 177, no. 19 (1995): 5539–46. http://dx.doi.org/10.1128/jb.177.19.5539-5546.1995.

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Nout, M. J. R., H. M. Bouwmeester, J. Haaksma, and H. Van Dijk. "Fungal growth in silages of sugarbeet press pulp and maize." Journal of Agricultural Science 121, no. 3 (December 1993): 323–26. http://dx.doi.org/10.1017/s0021859600085506.

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SUMMARYFungal spoilage of animal feed silage occurs frequently. In spoiled silage of sugarbeet press pulp sampled in The Netherlands during the period 1986–90, 40% of the samples were infested byPenicillium roquefortii. Other fungi of health significance includedAspergillus fumigatus(8% of all samples) andByssochlamysspp. (4 % of all samples). P.roquefortiiis also the dominant spoilage mould in maize silage. However, no PR-toxin could be detected in 25 lumps of P.roquefortii-intested maize silage, although one lump contained a fluorescent substance, with an Rff-value close to that of PR-toxin. This silage sample was not mutagenic, but had a cytotoxic effect towardsSalmonella typhimuriumin the Ames test. All P.roquefortii-infested lumps contained fluorescent fungal metabolites which were absent in samples taken at 5 cm distance from the corresponding lumps in the silage heaps. It is recommended that lumps of fungal-infested silage are removed before feeding the silage to cattle.

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Journal articles on the topic 'RFF'

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