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Cheng, Liwei, Manika Prasad, Reinaldo J. Michelena, et al. "Using rock-physics models to validate rock composition from multimineral log analysis." GEOPHYSICS 87, no. 2 (2022): MR49—MR62. http://dx.doi.org/10.1190/geo2020-0918.1.
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Multimineral log analysis is a quantitative formation evaluation tool for geologic and petrophysical reservoir characterization. Rock composition can be estimated by solving equations that relate log measurements to the petrophysical endpoints of minerals and fluids. Due to errors in log data and uncertainties in petrophysical endpoints of constituents, we have used effective medium models from rock physics as additional independent information to validate or constrain the results. We examine the Voigt-Reuss (VR) bound model, self-consistent approximation (SCA), and differential effective medium (DEM). The VR bound model provides the first-order quality control of multimineral results. We first show a conventional carbonate reservoir study with intervals in which the predicted effective medium models from multimineral results are inconsistent with measured elastic properties. We use the VR bound model as an inequality constraint in multimineral analysis for plausible alternative solutions. The SCA and DEM models provide good estimates in low-porosity intervals and imply geologic information for porous intervals. Then, we present a field case of the Bakken and Three Forks formations. A linear interpolation of the VR bound model helps validate multimineral results and approximate the elastic moduli of clay. There are two major advantages to using our new method: (1) Rock-physics effective medium models provide independent quality control of petrophysical multimineral results and (2) multimineral information leads to realistic rock-physics models.
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Feng, Zhou, Xin-Tong Li, Hong-Liang Wu, Shou-Ji Xia, and Ying-Ming Liu. "Multimineral optimization processing method based on elemental capture spectroscopy logging." Applied Geophysics 11, no. 1 (2014): 41–49. http://dx.doi.org/10.1007/s11770-014-0419-3.
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Li, Xuejiao, Wensheng Wang, Zhiqing Zhu, and Kunkun Zheng. "Investigation on Durability Behaviour and Optimization of Concrete with Triple-Admixtures Subjected to Freeze-Thaw Cycles in Salt Solution." Advances in Materials Science and Engineering 2021 (February 9, 2021): 1–16. http://dx.doi.org/10.1155/2021/5572011.
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In the seasonal frozen area of northeast China, cement concrete is usually in a working environment of cold climate and chlorine erosion coupling effect. In general, with a reasonable addition of air entraining agent (AEA) and multimineral admixtures such as fly ash, blast furnace slag, and silica fume, the durability of cement concrete under the effects of freeze-thaw and salt solution can be significantly improved in cold regions. However, due to several more compositions of cement concrete with multiple mineral admixtures, it would take excessive trial mixtures to select the desired mixture proportion based on the conventional method. This means a great deal of costs of raw materials and laboratory experimental time. In this paper, the experimental scheme of mixture proportion for air-entrained concrete with multimineral admixtures was designed based on the orthogonal experiment design method. Based on the compressive strength, rapid chloride permeability, and weight loss and relative dynamic elastic modulus after salt freeze-thaw cycles, the influence of different mineral admixtures and their dosages on the durability of concrete subjected to freeze-thaw in salt solution was analyzed. After that, based on genetic algorithm, an optimization of mixture proportion was proposed, which only requires less trial mixes and accessible optimization process. The test results indicated the superiority of air-entrained concrete with multimineral admixtures when serving in salt freeze-thaw environment. Eventually, it was also verified that the optimized concrete in this paper could achieve pleasurable durability performances under salt freeze-thaw cycles.
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Chen, Pei, Renata Atkinson, and Wayne R. Wolf. "Single-Laboratory Validation of a High-Performance Liquid Chromatographic-Diode Array Detector-Fluorescence Detector/Mass Spectrometric Method for Simultaneous Determination of Water-Soluble Vitamins in Multivitamin Dietary Tablets." Journal of AOAC INTERNATIONAL 92, no. 2 (2009): 680–88. http://dx.doi.org/10.1093/jaoac/92.2.680.
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Abstract The purpose of this study was to develop a single-laboratory validated (SLV) method using high-performance liquid chromatography with different detectors diode array detector (DAD); fluorescence detector (FLD); and mass spectrometry (MS) for determination of 7 B-complex vitamins (B1-thiamin, B2-riboflavin, B3-nicotinamide, B6-pyridoxine, B9-folic acid, pantothenic acid, and biotin) and vitamin C in multivitamin/multimineral dietary supplements. The method involves the use of a reversed-phase octadecylsilyl column (4 m, 250 2.0 mm id) and a gradient mobile phase profile. Gradient elution was performed at a flow rate of 0.25 mL/min. After a 5 min isocratic elution at 100 A (0.1 formic acid in water), a linear gradient to 50 A and 50 B (0.1 formic acid in acetonitrile) at 15 min was employed. Detection was performed with a DAD as well as either an FLD or a triple-quadrupole MS detector in the multiple reaction monitoring mode. SLV was performed using Standard Reference Material (SRM) 3280 Multivitamin/Multimineral Tablets, being developed by the National Institute of Standards and Technology, with support by the Office of Dietary Supplements of the National Institutes of Health. Phosphate buffer (10 mM, pH 2.0) extracts of the NIST SRM 3280 were analyzed by the liquid chromatographic (LC)-DAD-FLD/MS method. Following extraction, the method does not require any sample cleanup/preconcentration steps except centrifugation and filtration.
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Saroji, Sudarmaji, Wandia Mellani Trihapsari, and Muhammad Destrayuda Trisna. "Implementation of Deterministic and Multimineral Method in Petrophysical Analysis for Identifying Low Resistivity Reservoir in Tesla Field, Air Benakat Formation, South Sumatera Basin." Aceh International Journal of Science and Technology 13, no. 3 (2025): 180–92. https://doi.org/10.13170/aijst.13.3.36698.
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The Tesla field is located in the South Sumatra Basin, where there is the Air Benakat Formation, with the constituent rocks being dominated by alternating sandstone and claystone so that it is a shaly sand environment with the potential to become a low-resistivity hydrocarbon reservoir. Hydrocarbon reservoirs generally have a resistivity log value of more than 10 Ωm; when a hydrocarbon reservoir has a low-resistivity value between 0.5 - 5 Ωm, it is referred to as a low-resistivity hydrocarbon reservoir. Initially, deterministic analysis was carried out to calculate the petrophysical parameters of the potentially low-resistivity reservoirs. However, the results show a low validation value of petrophysics parameters, such as effective porosity and water saturation, when compared to the DST data, so a multimineral analysis is carried out to increase the validation value of the petrophysical parameters. The use of the multimineral method has produced the petrophysics parameter closer to DST Data when compared to the petrophysics parameter produced by the deterministic method in Tesla Field. The formation analysis shows that the low resistivity reservoir in the Tesla Field is caused by the grain size of the sandstone, which is very fine so that it can bind water significantly (irreducible water), abundant shale content, and distributed by lamination of shale, dispersed shale, and structural shale as well as the presence of conductive glauconite minerals.
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Felice, Valeria, Denise O’Gorman, Nora O’Brien, and Niall Hyland. "Bioaccessibility and Bioavailability of a Marine-Derived Multimineral, Aquamin-Magnesium." Nutrients 10, no. 7 (2018): 912. http://dx.doi.org/10.3390/nu10070912.
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Introduction: Magnesium is an essential mineral involved in a range of key biochemical pathways. Several magnesium supplements are present on the market and their degree of bioavailability differs depending on the form of magnesium salt used. Aquamin-Mg is a natural source of magnesium, containing 72 additional trace minerals derived from the clean waters off the Irish coast. However, the in vitro bioaccessibility and bioavailability of Aquamin-Mg in comparison with other supplement sources of magnesium has yet to be tested. Method: Aquamin-Mg, magnesium chloride (MgCl2) and magnesium oxide (MgO) were subjected to gastrointestinal digestion according to the harmonized INFOGEST in vitro digestion method and in vitro bioavailability tested using the Caco-2 cell model. Magnesium concentration was measured by atomic absorption spectrophotometry (AAS). Results: Magnesium recovery from both Aquamin-Mg and MgCl2 was greater than for MgO. Magnesium from all three sources was transported across the epithelial monolayer with Aquamin-Mg displaying a comparable profile to the more bioavailable MgCl2. Conclusions: Our data support that magnesium derived from a marine-derived multimineral product is bioavailable to a significantly greater degree than MgO and displays a similar profile to the more bioavailable MgCl2 and may offer additional health benefits given its multimineral profile.
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Clarke, D. L., and A. P. Clare. "AN INTEGRATED PETROPHYSICAL WORKFLOW TO GENERATING FLUID SUBSTITUTED LOGS FOR AVO CHARACTERISATION—GIPSY AND NORTH GIPSY FIELDS CASE STUDY, NORTH WEST SHELF, AUSTRALIA." APPEA Journal 42, no. 1 (2002): 477. http://dx.doi.org/10.1071/aj01026.
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As part of a multi-well field study an integrated petrophysical workflow was developed to include the generation of fluid substituted logs for AVO characterisation.The workflow relied upon the construction of a multimineral model that best approximated the actual mineral content of the reservoir. Any limitations or assumptions were noted and taken into account when creating the multi-mineral model. Other petrophysical results were derived from the same model to validate its consistency such as intrinsic permeability, porosity, water saturation, etc. Iteration between the model and the results was required until a consistent model was achieved.The estimation of an intrinsic permeability log was based upon the k-Lambda method that uses the multimineral model and porosities.The estimation of a shear slowness log and the fluid substituted logs was based upon elastic rock properties derived from the multi-mineral model and the acquired compressional slowness log and bulk density log. This integrated approach provides a higher confidence in the derived results, which are then used as input into the reservoir model, thereby improving the reserve calculations.The interdependence of each derived result on the same input multi-mineral model ensures consistency and predictability in a complex geological environment, which captures all available information.The method is demonstrated with the Gipsy–1 and North Gipsy–1 wells, which were part of the original field study.
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Nicolás-López, Rubén, Oscar C. Valdiviezo-Mijangos, Jaime Meléndez-Martínez, and Valeriy M. Levin. "A multimineral Rock Physics Template built from the Perfectly Disordered Method for shale lithology interpretation." Journal of Petroleum Science and Engineering 176 (May 2019): 532–36. http://dx.doi.org/10.1016/j.petrol.2019.01.095.
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Liu, Mingxin, Yongfei Yang, Fugui Liu, et al. "Thermal disturbance anisotropy and structural stability in deep multimineral granular systems: A discrete element method study." Geothermics 132 (November 2025): 103439. https://doi.org/10.1016/j.geothermics.2025.103439.
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Burke, Lauri A., Justin E. Birdwell, and Stanley T. Paxton. "Multimineral petrophysics of thermally immature Eagle Ford Group and Cretaceous mudstones, U.S. Geological Survey Gulf Coast 1 research wellbore in central Texas." Interpretation 10, no. 1 (2021): T151—T165. http://dx.doi.org/10.1190/int-2021-0094.1.
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Traditional petrophysical methods to evaluate organic richness and mineralogy using gamma-ray and resistivity log responses are not diagnostic in source rocks. We have developed a deterministic, nonproprietary method to quantify formation variability in total organic carbon (TOC) and three key mudrock mineralogical components of nonhydrocarbon-bearing source rock strata of the Eagle Ford Group by developing a set of log-derived multimineral models calibrated with Fourier transform infrared spectroscopy core data from the research borehole U.S. Geological Survey Gulf Coast 1 West Woodway. We determined that bulk density response is a reliable indicator of organic content in these thermally immature, water-bearing source rocks. Multimineral findings indicate that a high degree of laminae-scale mineralogical heterogeneity exists due to thinly interbedded carbonate cements amid clay-rich mudstone layers. The lower part of the Eagle Ford Group contains the highest average TOC content (4.7 wt%) and the highest average carbonate volume (64.1 vol%), making it the optimal target in thermally mature areas for source-rock potential and hydraulic-fracture placement. In contrast, the uppermost portion of the Eagle Ford Group contains the highest average volume of clay minerals (42.6 vol%), which increases the potential for wellbore stability issues. Petrophysical characterization reveals that porosity is approximately 30% in this relatively uncompacted formation. In this thermally immature source rock, water saturation is nearly 100% and no free hydrocarbons were observed on the resistivity logs. No evidence of borehole ellipticity was observed on the three-arm caliper log, and horizontal stresses are presumed to be directionally uniform in the vicinity of this near-surface wellbore. This shallow wellbore has a temperature gradient of 1.87°F/100 ft (16.3°C/km) and is likely influenced by earth surface heating.
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Yu, Anghong, Haizeng Liu, Chuanzhen Wang, et al. "Online Ash Content Monitor by Automatic Composition Identification and Dynamic Parameter Adjustment Method in Multicoal Preparation." Processes 10, no. 8 (2022): 1432. http://dx.doi.org/10.3390/pr10081432.
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The online measurement of coal ash has overcome the shortcomings of chemical tests. However, there could be large fluctuations and errors in the results of online ash monitors because of the transient change in coal quality resulting from different geological conditions in the mining process. In this study, to resolve the problems of the dual-energy γ-ray online ash monitor in the Linhuan Coal Preparation Plant, we investigated the internal factors, such as the composition of multimineral and multicoal, and external factors, such as the moisture and impurities, which affect the measurement results of the coal ash monitor. Furthermore, we developed a mathematical model to determine the effect of relevant factors on the coefficient of the online ash monitor, which revealed the relationship between coal composition and the parameters of the ash monitor, ensuring the stable and accurate measurement of ash in clean coal. The method of determining parameters used in the case of coal blending has been applied in the Linhuan Coal Preparation Plant. By comparing with tested ash content, the average absolute error and relative error for daily ash content measured in April are 0.21 and 2.18%, respectively. Meanwhile, it shows certain accuracy and reproducibility while opposed to the daily average absolute error of 0.22 and relative error of 2.39% in May.
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Patil, Suyog S., and Ashwini K. Srivastava. "Development and Validation of Rapid Ion-Pair RPLC Method for Simultaneous Determination of Certain B-Complex Vitamins Along with Vitamin C." Journal of AOAC INTERNATIONAL 95, no. 1 (2012): 74–83. http://dx.doi.org/10.5740/jaoacint.11-014.
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Abstract A rapid, simple, and accurate ion-pair RPLC method has been developed for simultaneous analysis of vitamin C and major B-complex vitamins. An RP C18 column thermostated at 30°C was used with gradient elution of mobile phase comprising 10 mM potassium dihydrogen phosphate buffer (containing 3 mM sodium hexane-1-sulfonate, adjusted to pH 2.80 with o-phosphoric acid) and methanol at a flow rate of 1.0 mL/min to achieve the best possible separation and resolution of all vitamins in about 11.00 min. The detection was performed at 274 nm. The method has been implemented successfully for simultaneous determination of vitamins present in 12 multivitamin/multimineral pharmaceutical preparations, as well as in human urine. Typical validation characteristics were evaluated in accordance with International Conference on Harmonization guidelines. Good linearity over the investigated concentration levels was observed. Intraday repeatability was ≤2.0%, and interday variation was ≤2.6%, for all vitamins. The method can be used for assay of these vitamins over a wide concentration range with good precision and accuracy; hence, it would be appropriate for routine QC as well as in clinical analysis.
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Sánchez, María C., Ana Herráiz, María J. Ciudad, et al. "Metabolomics and Biochemical Benefits of Multivitamin and Multimineral Supplementation in Healthy Individuals: A Pilot Study." Foods 13, no. 14 (2024): 2207. http://dx.doi.org/10.3390/foods13142207.
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Scientific evidence regarding the effectiveness of vitamin and mineral supplements in healthy individuals remains scarce. In a randomized, double-blind study, 30 healthy individuals were assigned to receive a single daily dose of multivitamin and multimineral supplementation or a double daily dose for 30 days. Before and after the intake, an untargeted metabolomics assay for serum metabolites was conducted by hydrophilic interaction liquid chromatography–mass spectrometry, and clinical assessments of peripheral blood samples were performed. A paired t-test for metabolic analysis, adjusted using the false discovery rate (FDR) and p-value correction method (rate of change > 2 and FDR < 0.05), the Shapiro–Wilk test, Student’s t-test, and the Mann–Whitney U test were applied depending on the variable, with a 5% significance level. An impact on oxidative stress was observed, with a significant reduction in homocysteine levels and an increment of pyridoxic acid (vitamin B6). The effect on energy metabolism was shown by a significant increase in diverse metabolites, such as linoleoylcarnitine. Serum iron and calcium levels were also impacted. Overall, we observed a nutritional balance compatible with a good state of health. In conclusion, beneficial effects on adult health were demonstrated in relation to oxidative stress, energy metabolism, and nutritional balance.
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Wallace, Taylor, Cara Frankenfeld, Balz Frei, et al. "Multivitamin Use Is Associated with Increased Micronutrient Intakes and Biomarkers and Decreased Prevalence of Inadequacies in Middle-Aged and Older Adults." Current Developments in Nutrition 4, Supplement_2 (2020): 1501. http://dx.doi.org/10.1093/cdn/nzaa061_129.
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Abstract Objectives Micronutrient inadequacies are common in older adults. We sought to assess if multivitamin/multimineral supplement (MVM) use improved micronutrient intake and biomarker status among older adults enrolled in NHANES. Methods The National Cancer Institute Method was used to estimate usual intakes of 18 micronutrients stratified by age and frequency of MVM use. Insufficiency and deficiency prevalence were evaluated using nutrient biomarkers. Results Compared with food alone, MVM use was associated with higher nutrient intake and lower prevalence of inadequacies of almost all micronutrients exam- ined and improved nutrient biomarker status of folate, iodine, selenium, and vitamins B6, B12, and D. Regular MVM use (!16days/month) decreased the odds of clinical deficiency (defined by biomarker status) of vitamins B6 and D but increased the proportion exceeding the tolerable upper intake level of folic acid. Vitamin B6 deficiency in MVM non-users was common and increased with age. Conclusions Recommending MVM in the middle-aged and older adult population in the US may help to ensure opti- mal long-term nutritional status and contribute to health maintenance. Funding Sources GSK Consumer Healthcare.
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El-Maghrabey, Mahmoud, Shōta Seino, Naoya Kishikawa, and Naotaka Kuroda. "The Development of a Selective Colorimetric Sensor for Cu2+ and Zn2+ in Mineral Supplement with Application of a Smartphone Paper-Based Assay of Cu2+ in Water Samples." Sensors 24, no. 23 (2024): 7844. https://doi.org/10.3390/s24237844.
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Herein, we developed a colorimetric method for the determination of Cu2+ and Zn2+ using NBD-G as a novel selective metal sensor. NBD-G was easily synthesized by a nucleophilic substitution reaction between 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) and Girard’s Reagent P. The NBD-G solution is yellow, but when it reacts with Cu2+ and Zn2+, its color changes selectively to red (510 nm) and orange (480 nm), respectively. NBD-G was used as a sensor for Cu2+ and Zn2+, showing a high sensitivity down to 0.77 µM for Cu2+ and 1.66 µM for Zn2+. NBD-G could determine both metals simultaneously; thus, it was applied to determine them in multimineral supplements, which showed excellent recoveries. Next, a filter paper impregnated with NBD-G was prepared as a test paper, and a simple, selective, and rapid onsite method for quantifying Cu2+ was developed as, interestingly, the paper showed no change upon the addition of Zn2+. Next, Cu2+ could be quantified with high selectivity and accuracy by photographing the color change with a smartphone camera and processing the image with Image J. The detection limit for Cu2+ using this method was 3.9 µM. Finally, the NBD-G test paper method was able to satisfactorily quantify Cu2+ spiked into the rainwater.
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CASONI, Dorina, Michaela PONTA, Mihaela-Nicoleta BIBICA, Ioana-Violeta LAZAR, and Tiberiu FRENTIU. "A free non-spectral interferences method based on inductively coupled plasma optical emission spectrometry for multielemental determination in multimineral/multivitamin preparations." Revue Roumaine de Chimie 65, no. 6 (2020): 573–78. http://dx.doi.org/10.33224/rrch.2020.65.6.07.
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Szabó, Norbert Péter, and Mihály Dobróka. "Robust estimation of reservoir shaliness by iteratively reweighted factor analysis." GEOPHYSICS 82, no. 2 (2017): D69—D83. http://dx.doi.org/10.1190/geo2016-0393.1.
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We suggest a statistical method for the simultaneous processing of electric, nuclear, and sonic-logging data using a robust iteratively reweighted factor analysis (IRFA). After giving a first estimate by Jöreskog’s approximate method, we refine the factor loadings and factor scores jointly in an iterative procedure, during which the deviation between the measured and calculated data is weighted in proportion to its magnitude for giving an outlier-free solution. We show a strong nonlinear relation between the first factor and the shale volume of multimineral hydrocarbon formations. We test the noise rejection capability of the new statistical procedure by making synthetic modeling experiments. The IRFA of simulated well-logging data including a high amount of noise gives a well log of the shale volume purified of large errors. Case studies from Hungary and the USA show that the results of factor analysis are consistent with that of independent deterministic modeling and core data. The statistical workflow can be effectively used for the processing of not normally distributed and extremely noisy well-logging data sets to evaluate the shale content and derived petrophysical properties more accurately in reservoir rocks.
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Mohd Zaki, Nor Azian, Mohd Naim Rasidi, S. Maria Awaluddin, Tee Guat Hiong, Hasimah Ismail, and Noor Safiza Mohamad Nor. "Prevalence and Characteristic of Dietary Supplement Users in Malaysia: Data From the Malaysian Adult Nutrition Survey (MANS) 2014." Global Journal of Health Science 10, no. 12 (2018): 127. http://dx.doi.org/10.5539/gjhs.v10n12p127.
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BACKGROUND: There has been an increase trend of dietary supplements intake among Malaysians over the last decade. The aim of this study was to determine the prevalence and characteristic of dietary supplements users among adults in Malaysia. METHODS: Data of 3000 respondents aged 18&ndash;59 years from the Malaysian Adult Nutrition Survey (MANS) 2014 were utilized. A multi-stage stratified sampling method was employed and eligible respondent from each household was selected using Kish method. Validated questionnaire was used to gather information on vitamin/mineral supplements (VMS) and food supplements (FS). Descriptive analysis and multiple logistic regressions were conducted using SPSS version 20.0. RESULTS: The prevalence of VMS and FS intakes among adults in Malaysian were 28.1% and 34.0% respectively. Women, older aged adults with higher education level and monthly income were more likely to consume dietary supplements. Vitamin C and multivitamin/ multimineral, were the commonest VMS consumed by the respondents. The most common FS taken were fish oil and royal jelly. The main causes for dietary supplements intake include for health reasons, doctor&rsquo;s prescription, to increase energy level and for beauty. CONCLUSIONS: About one third of the Malaysian adults took variety of dietary supplements. Thus, information based on the scientific evidences of health benefits for each type of the dietary supplements is needed to enable consumers to make informed choices on the dietary supplements.
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Heidari, Zoya, Carlos Torres-Verdín, and William E. Preeg. "Improved estimation of mineral and fluid volumetric concentrations from well logs in thinly bedded and invaded formations." GEOPHYSICS 77, no. 3 (2012): WA79—WA98. http://dx.doi.org/10.1190/geo2011-0454.1.
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Calculation of mineral and fluid volumetric concentrations from well logs is one of the most important outcomes of formation evaluation. Conventional estimation methods assume linear or quasi-linear relationships between volumetric concentrations of solid/fluid constituents and well logs. Experience shows, however, that the relationship between neutron porosity logs and mineral concentrations is generally nonlinear. More importantly, linear estimation methods do not explicitly account for shoulder-bed and/or invasion effects on well logs, nor do they account for differences in the volume of investigation of the measurements involved in the estimation. The latter deficiencies of linear estimation methods can cause appreciable errors in the calculation of porosity and hydrocarbon pore volume. We investigated three nonlinear inversion methods for assessment of volumetric concentrations of mineral and fluid constituents of rocks from multiple well logs. All three of these methods accounted for the general nonlinear relationship between well logs, mineral concentrations, and fluid saturations. The first method accounted for the combined effects of invasion and shoulder beds on well logs. The second method also accounted for shoulder-bed effects but was intended for cases where mud-filtrate invasion is negligible or radially deep. Finally, the third method was designed specifically for analysis of thick beds where mud-filtrate invasion is either negligible or radially deep. Numerical synthetic examples of application indicated that nonlinear inversion of multiple well logs is a reliable method to quantify complex mineral and fluid compositions in the presence of thin beds and invasion. Comparison of results against those obtained with conventional multimineral estimation methods confirmed the advantage of nonlinear inversion of multiple well logs in quantifying thinly bedded invaded formations with variable and complex lithology, such as those often encountered in carbonate formations.
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Li, Kelei, Chunxiao Liu, Xiaotong Kuang, Qingxue Deng, Feng Zhao, and Duo Li. "Effects of Multivitamin and Multimineral Supplementation on Blood Pressure: A Meta-Analysis of 12 Randomized Controlled Trials." Nutrients 10, no. 8 (2018): 1018. http://dx.doi.org/10.3390/nu10081018.
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Previous studies have not drawn a consistent conclusion about effect of multivitamin and multimineral supplementation (MVMS) on blood pressure. A comprehensive search of PubMed, Embase and Cochrane Library (up to May 2018) and references of relevant articles was undertaken. The present meta-analysis included 12 randomized controlled trials (RCTs), of which eight RCTs in 2011 subjects evaluated the effect of MVMS on blood pressure and four RCTs in 21,196 subjects evaluated the effect of MVMS on the risk of hypertension. MVMS had a lowering effect on systolic blood pressure (SBP) and diastolic blood pressure (DBP): the weighted mean difference (WMD) was −1.31 mmHg (95% CI, −2.48 to −0.14 mmHg) and −0.71 mmHg (95% CI, −1.43 to 0.00 mmHg), respectively. Subgroup analysis indicated that the lowering effect of MVMS on blood pressure was only significant in 134 subjects with chronic disease but not in 1580 healthy subjects, and the WMD for systolic blood pressure (SBP) and DBP in subjects with chronic disease was −6.29 mmHg (95% CI, −11.09 to −1.50 mmHg) and −2.32 mmHg (95% CI, −4.50 to −0.13 mmHg), respectively. The effect size of MVMS on SBP in 58 hypertensive subjects (WMD, −7.98 mmHg; 95% CI, −14.95 to −1.02 mmHg) was more than six times of that in 1656 normotensive subjects (WMD, −1.25 mmHg; 95% CI, −2.48 to −0.02 mmHg). However, no significant effect on DBP was observed in both hypertensive and normotensive subgroups. There was no significant effect of MVMS on risk of hypertension in 22,852 subjects with a normal blood pressure at baseline. In conclusion, although MVMS had a significant lowering effect on blood pressure in normotensive subjects, the lowering effect was too small to effectively prevent future hypertension. MVMS may be an effective method for blood pressure control in subjects with chronic disease including hypertension, but the sample size of subjects with hypertension or other chronic disease was too small, and more well-designed RCTs are needed to confirm this result.
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Priyanka, Feni, Ordas Dewanto, Bagus Sapto Mulyatno, and Riezal Ariffiandhany. "KLASIFIKASI PETROFISIKA TIPE BATUAN UNTUK MEMPREDIKSI KUALITAS RESERVOAR PASIR SERPIHAN PADA FORMASI TALANG AKAR, CEKUNGAN ONWJ." Jurnal Geofisika Eksplorasi 4, no. 3 (2020): 28–40. http://dx.doi.org/10.23960/jge.v4i3.39.
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Hydrocarbons were accumulated in reservoir, the reservoir has a lot of types depending on the geological conditions and the constituent mineral. In ONWJ basins, sub-basins Arjuna, Talang Akar Formation is sand splintersreservoir type. The presence of clay in a reservoir will reduce the resistivity and increase thesaturation, so it takes a multimineral analysis and the reservoir qualityclassification. In this study, physical properties (porosity, permeability, Rw, and saturation) and the quality of the reservoir can be identified through petrophysical analysis by utilizing log data and core analysis, and the rocktypeprediction(using R35 Winland or HFU method). In this study 5 wells (IX-A1, IX-13, IX-4, IX-7 and IX-8)used and found eight hydrocarbon zones, 6 are validated by the DST (drill steam test)data, androck type method that suitable is the method of HFU (hydraulic flow units) due to the coefficient of correlation between porosity and permeability shows a value of 0.75, based on the calculations, the eight types of rock is conclude, where the dominance of the rock typeis the type 12 with a pore size between 5-10 microns, type reservoir rocks in this study belong to the lithofacies distributary channel and mouthbar sand. By knowing the petrophysical property values, it can determine reservoir productivity and determine the zone eligible to be produced or not, by using curve SMLP (Stratigraphic Modified Lorenz Plot).
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Lis-Śledziona, Anita. "Multiscale evaluation of a thin-bed reservoir." Geology, Geophysics and Environment 47, no. 1 (2021): 5–20. http://dx.doi.org/10.7494/geol.2021.47.1.5.
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A thin-bed laminated shaly-sand reservoir of the Miocene formation was evaluated using two methods: high resolution microresistivity data from the XRMI tool and conventional well logs. Based on high resolution data, the Earth model of the reservoir was defined in a way that allowed the analyzed interval to be subdivided into thin layers of sandstones, mudstones, and claystones. Theoretical logs of gamma ray, bulk density, horizontal and vertical resistivity were calculated based on the forward modeling method to describe the petrophysical properties of individual beds and calculate the clay volume, porosity, and water saturation. The relationships amongst the contents of minerals were established based on the XRD data from the neighboring wells; hence, the high-resolution lithological model was evaluated. Predicted curves and estimated volumes of minerals were used as an input in multimineral solver and based on the assumed petrophysical model the input data were recalculated, reconstructed and compared with the predicted curves. The volumes of minerals and input curves were adjusted during several runs to minimalize the error between predicted and recalculated variables. Another approach was based on electrofacies modeling using unsupervised self-organizing maps. As an input, conventional well logs were used. Then, the evaluated facies model was used during forward modeling of the effective porosity, horizontal resistivity and water saturation. The obtained results were compared and, finally, the effective thickness of the reservoir was established based on the results from the two methods.
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Grigor’eva, A. V., V. M. Kozlovskiy, G. A. Gridin, and A. A. Ostapchuk. "METAMORPHIC TRANSFORMATIONS OF ROCKS IN THE CENTRAL PART OF THE PRIMORSKY FAULT. WESTERN BAIKALIA." Доклады Российской академии наук. Науки о Земле 511, no. 2 (2023): 198–205. http://dx.doi.org/10.31857/s2686739723600807.
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In this paper we compare metamorphic transformations in acid and mafic rocks in a zone of intense tectonic movements. The object of study is the exhumed part of damage zone of Primorsky fault – main collision suture, which connects the Siberian Craton and the Olkhon Terrane. The studied area is located near the Khorga River. Collected metamorphic rock samples are represented by both acid (plagiogranitegneiss) and mafic (amphibole-biotite plagiogneisses) rocks. The samples present two different parent rocks contacting each other but differ in chemical composition. The formation of identical metamorphic minerals belonging to the groups of garnet and epidote is noted in both types of rocks. Mineral formation was associated with high-pressure regional metamorphism and possibly with later collision. Studying chemical composition of rock-forming minerals has allowed to determine the P-T condition of metamorphism in these rocks via the method of multimineral thermobarometry. It was established that conditions of early metamorphism retain in amphibole-biotite plagiogneiss. Early metamorphism is characterized by high-pressure amphibolite facies of medium temperature next to eclogite facies. In plagiogranitegneisses were found conditions of later metamorphism that formed rocks at the same pressure but at a lower temperature in the paragonite-kyanite-zoisite subfacies of the eclogite facies next to the greenschist facies. Minerals formed in the early metamorphism are poorly preserved.
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Brämswig, Susanne, Reinhild Prinz-Langenohl, Yvonne Lamers, et al. "Supplementation with a multivitamin containing 800 µg of folic acid shortens the time to reach the preventive red blood cell folate concentration in healthy women." International Journal for Vitamin and Nutrition Research 79, no. 2 (2009): 61–70. http://dx.doi.org/10.1024/0300-9831.79.2.61.
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Background: The lowest risk of having a child with a neural tube defect (NTD) was related to red blood cell (RBC) folate concentrations of >906 nmol/L. For NTD prevention, it is recommended that women use periconceptional supplementation of 400 µg/day folic acid. Using this dose previous studies indicate that RBC folate >906 nmol/L was not reached within four weeks of supplementation. Objective: The effectiveness of a multivitamin/multimineral supplement containing 800 µg folic acid (verum) was evaluated using RBC folate concentration exceeding 906 nmol/L as primary endpoint. In addition, the time frame of achieving the threshold level was established as well as the effect of supplementation of other B vitamins on folate metabolism. Subjects and Methods: 46 healthy females received 800 µg/day of folic acid or placebo for 16 weeks. Blood samples were collected in four-week intervals. Plasma and RBC folate were measured with the microbiological method. Results: Mean (±SED) RBC folate increased over time to 1430±53 nmol/L, but did not reach a steady state after 16 weeks of intervention. Mean time to reach the target level was 4.2 ± 3.5 weeks in the verum group. Intake of verum also led to an increase over time of plasma folate. Conclusions: Preventive RBC folate concentration of more than 906 nmol/L can be reached within four weeks of supplementation with daily intake of 800 µg folic acid. With respect to NTD prevention, we suggest the re-evaluation of the current recommendation of folic acid supplementation.
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Heidari, Zoya, and Carlos Torres-Verdín. "Inversion-based method for estimating total organic carbon and porosity and for diagnosing mineral constituents from multiple well logs in shale-gas formations." Interpretation 1, no. 1 (2013): T113—T123. http://dx.doi.org/10.1190/int-2013-0014.1.
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Reliable estimates of petrophysical and compositional properties of organic shale are critical for detecting perforation zones or candidates for hydro-fracturing jobs. Current methods for in situ formation evaluation of organic shale largely rely on qualitative responses and empirical formulas. Even core measurements can be inconsistent and inaccurate when evaluating clay minerals and other grain constituents. We implement a recently introduced inversion-based method for organic-shale evaluation from conventional well logs. The objective is to estimate total porosity, total organic carbon (TOC), and volumetric/weight concentrations of mineral/fluid constituents. After detecting bed boundaries, the first step of the method is to perform separate inversion of individual well logs to estimate bed physical properties such as density, neutron migration length, electrical conductivity, photoelectric factor (PEF), and thorium, uranium , and potassium volumetric/weight concentrations. Next, a multilayer petrophysical model specific to organic shale is constructed with an initial guess obtained from conventional well-log interpretation or X-ray diffraction data; bed physical properties are calculated with the initial layer-by-layer values. Final estimates of organic shale petrophysical and compositional properties are obtained by progressively minimizing the difference between calculated and measured bed properties. A unique advantage of this method is the correction of shoulder-bed effects on well logs, which are prevalent in shale-gas plays. Another advantage is the explicit calculation of accurate well-log responses for specific petrophysical, mineral, fluid, and kerogen properties based on chemical formulas and volumetric concentrations of minerals/kerogen and fluid constituents. Examples are described of the successful application of the new organic-shale evaluation method in the Haynesville shale-gas formation. This formation includes complex solid compositions and thin beds where rapid depth variations of mineral/fluid constituents are commonplace. Comparison of estimates for total porosity, total water saturation, and TOC obtained with (a) commercial software for multimineral analysis, (b) our organic-shale evaluation method, and (c) core/X-ray diffraction measurements indicates a significant improvement in estimates of total porosity and water saturation yielded by our interpretation method. The estimated TOC is also in agreement with core laboratory measurements.
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Fraga, Edmundo, Ana Cuesta, Jesus Zea-Garcia, Angeles De la Torre, Armando Yáñez-Casal, and Miguel Aranda. "Rietveld Quantitative Phase Analysis of Oil Well Cement: In Situ Hydration Study at 150 Bars and 150 °C." Materials 12, no. 12 (2019): 1897. http://dx.doi.org/10.3390/ma12121897.
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Oil and gas well cements are multimineral materials that hydrate under high pressure and temperature. Their overall reactivity at early ages is studied by a number of techniques including through the use of the consistometer. However, for a proper understanding of the performance of these cements in the field, the reactivity of every component, in real-world conditions, must be analysed. To date, in situ high energy synchrotron powder diffraction studies of hydrating oil well cement pastes have been carried out, but the quality of the data was not appropriated for Rietveld quantitative phase analyses. Therefore, the phase reactivities were followed by the inspection of the evolution of non-overlapped diffraction peaks. Very recently, we have developed a new cell specially designed to rotate under high pressure and temperature. Here, this spinning capillary cell is used for in situ studies of the hydration of a commercial oil well cement paste at 150 bars and 150 °C. The powder diffraction data were analysed by the Rietveld method to quantitatively determine the reactivities of each component phase. The reaction degree of alite was 90% after 7 h, and that of belite was 42% at 14 h. These analyses are accurate, as the in situ measured crystalline portlandite content at the end of the experiment, 12.9 wt%, compares relatively well with the value determined ex situ by thermal analysis, i.e., 14.0 wt%. The crystalline calcium silicates forming at 150 bars and 150 °C are also discussed.
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Jun, Jia, Xue Kunlin, Ni Liping, Luo Yang, and Liu Yuchao. "Logging Response Mechanism and Content Evaluation of Laumontite-Bearing Glutenite Reservoir: A Case Study of Lower Urho Formation of Permian of the Junggar Basin." Geofluids 2024 (March 6, 2024): 1–13. http://dx.doi.org/10.1155/2024/1592800.
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The Urho Formation in the Lower Permian System at the Junggar Basin in China commonly develops zeolite cements. The presence of zeolite minerals in various states of occurrence and uneven distribution in glutenite reservoirs makes it indeterminate to interpret the well logging response characteristics such as acoustic, resistivity, radioactivity, and nuclear magnetic resonance (NMR). This poses significant challenges for the evaluation of well loggings in glutenite reservoirs containing laumontite and the determination of oil and gas reserves. In this study, through petrophysics experiments such as whole-rock X-ray diffraction, conventional petrophysical properties, mercury injection, and electron microprobe analysis, the characteristics of glutenite reservoirs containing laumontite and the well logging response mechanisms were analyzed from the perspectives of mineral composition of rocks, geochemical characteristics, and principle of loggings. A multimineral optimization method was used to calculate the laumontite content. The results indicate that in the study area, the cementation of zeolite minerals dominated by laumontite suppresses the pore development in the reservoir, which is a crucial factor in the formation of complex pore structures and low-porosity low-permeability reservoirs. Since laumontite exhibits a water-bearing framework structure with numerous micropores and crystal water, the laumontite-bearing glutenite reservoirs are characterized by low natural gamma radiation, low density, high neutron porosity, and high electrical resistivity. The acoustic interval transit time shows no significant differences, while the NMR T2 spectrum exhibits a short relaxation time.
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Mattavelli, Margherita G. M., Giacomo Piccininni, Gabriel F. Toti, et al. "Iron Supply of Multivitamins–Multiminerals Commercialized Online by Amazon in Western and Southern Europe: A Labeling Analysis." Nutrients 16, no. 18 (2024): 3140. http://dx.doi.org/10.3390/nu16183140.
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Background. In high-income countries, shopping for non-prescription multivitamin–multimineral supplements has tremendously increased. Objective and Methods. The purpose of this labeling analysis is to inform on the daily elemental iron (with or without vitamin C) supply provided by multivitamin–multimineral supplements sold online by Amazon in Western and Southern Europe (amazon.es®, amazon.de®, amazon.it®, and amazon.fr®). Results. We identified 298 iron-containing multivitamin–multimineral preparations sold by Amazon marketplaces: 153 preparations sourced from amazon.de®, 68 from amazon.fr®, 54 from amazon.it®, and 23 from amazon.es®. The daily iron dose provided by these preparations was 14 [5–14] mg (median and interquartile range), with no differences among the marketplaces. Approximately 90% (n = 265) of the preparations contained ferrous iron. Moreover, 85% (n = 253) of the preparations were fortified with vitamin C in a dose of 80 [40–100] mg daily. Conclusions. The median supply of iron (about 14 mg) and vitamin C (80 mg) in iron-containing multivitamin–multimineral preparations offered on Amazon platforms in Western and Southern Europe falls below that currently recommended for iron deficiency in review articles, namely 100 mg of iron and 500 mg of vitamin C per day. The iron supply of iron-containing multivitamin–multimineral preparations falls also below the dose of 30–60 mg advocated to prevent iron deficiency in menstruating women.
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Kumar, Sunaj, Debarati Mishra, Soma Chatterjee, R. R. Tiwari, and V. L. N. Avadhani. "Rock Physics Modeling of Gas Hydrate Reservoirs Through Integrated Core and Well-Log Data in NGHP-02 Area in KG Offshore Basin, India." Petrophysics – The SPWLA Journal of Formation Evaluation and Reservoir Description 63, no. 2 (2022): 237–55. http://dx.doi.org/10.30632/pjv63n2-2022a6.
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Since gas hydrates are unconventional reservoirs, they pose unique challenges for identification, characterization, quantification, and extraction. The conventional approach—elastic logs—can provide a better method for identification through attribute analysis. On the other hand, geomechanical studies for wellbore stability analysis pave the way for the effective exploitation of gas hydrates. It is crucial to predict elastic logs against gas-hydrate-bearing sediments, which requires an effective rock physics model. In the present work, a study pertaining to the National Gas Hydrate Program-02 (NGHP-02) campaign in the Krishna‐Godavari (KG) Offshore Basin, India, where gas hydrates are deposited primarily in two facies—a shale-dominated shallower one and a sand-dominated deeper one that has been identified by responses of conventional and spectroscopy logs—is discussed. It is commonly known that depositional heterogeneity impacts petrophysical and elastic properties. To address this issue, an innovative approach has been adopted to model compressional and shear log data using rock physics modeling of gas hydrate reservoirs based on the depositional type of gas hydrate. Guidance from the change of compressional velocity data from log and core with an increase of gas hydrate saturation shows gas hydrate deposition in the study area can be explained through a matrix/grain-supported model. The Jason grain-supported rock physics model appeared best suited among different available rock physics models, depending on the clay volume and porosity in our study area. Using input from a robust multimineral petrophysical evaluation and rock physics modeling, the finalized model is propagated to test wells for predicting compressional, shear, and density logs, with the predicted data validated by core-measured compressional and shear data. Model consistency is indicated by a high correlation from multiwell crossplots of modeled and recorded elastic logs (compressional and shear velocity) with acoustic impedance. The developed rock physics model better discriminates gas hydrate in the shaly sand layer and gas hydrate in the sand-dominated layer, calcite, and shale in the VpVs domain.
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Carpenter, Chris. "Subsurface Data Reveal Pore-Pressure Variations in Shale Basins." Journal of Petroleum Technology 77, no. 02 (2025): 82–85. https://doi.org/10.2118/0225-0082-jpt.
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_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper URTeC 4042140, “Regional Pore-Pressure Variations of the Wolfcamp, Dean, Spraberry, and Bone Spring Formations of the Midland and Delaware Basins in the USA,” by Shuvajit Bhattacharya, Ray Eastwood, and Katie Smye, The University of Texas at Austin, et al. The paper has not been peer reviewed. _ The authors study regional pore-pressure variations in the Leonardian and Wolfcampian producing strata (Wolfcamp, Bone Spring, Avalon, Dean, and Spraberry) in the Midland and Delaware Basins of West Texas and southeast New Mexico. Pore pressure is analyzed with a variety of subsurface data, including sonic logs and completions data. Results show that pore pressure is consistently higher in the Wolfcamp Formation (especially Wolfcamp B, C, and D) and Delaware Basin Bone Spring S3 than the Spraberry Formation in the Midland Basin. Introduction Over the years, several studies have been conducted on pore pressure in different shale reservoirs in the Permian Basin. A few recent studies used 3D seismic data to estimate and map pore pressure in the Permian. However, few published studies exist on basinwide variations of pore pressure in producing shale formations in the Permian. Uncertainty persists as to why pore pressure is different in age-equivalent formations in the Delaware and Midland Basins. The authors study regional pore-pressure variation in selected Leonardian and Wolfcampian shale formations at the basin scale, integrating well logs, completions, and reservoir data. The challenges and opportunities presented by different kinds of subsurface data in estimating pore pressure are discussed. Pore-pressure-gradient maps reveal vertical and lateral changes in pore pressure in the Permian Basin. Methods Pore pressure of the Wolfcamp, Dean, Spraberry, Bone Spring, and Avalon Formations in the Midland and Delaware Basins was studied with a combination of sonic logs, instantaneous shut-in pressure (ISIP), diagnostic fluid injection tests (DFIT), mud weight, and other approaches. Pore Pressure From Sonic Logs. Two methods were used for obtaining pore-pressure estimates from sonic logs: Eaton’s approach and the SOPI method that uses sonic, offset well, porosity, and formation-resistivity data. Although resistivity logs were more prevalent than sonic logs in the Midland and Delaware Basins, the presence of both induction logs and laterologs was encountered; mixing the results from both data types would complicate workflow and interpretations. Using Eaton’s approach, a shale normal compaction trend line varying with depth was established. Departures from this trend were used to compute pore pressure using observed sonic travel time. For the SOPI method, wells with petrophysical multimineral model results that accurately characterized variations in lithology and porosity for the formations of interest were used. The sonic log response was forward-modeled using the derived mineral composition and porosity from petrophysical inversion.
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Fanani, Anhar Faisal, Nurul Fajrih, and Wa Laili Salido. "Penggunaan Minyak Ikan dalam Ransum Ayam Kampung terhadap Profil Lemak Darah." Jurnal Ilmu dan Teknologi Peternakan Tropis 6, no. 1 (2019): 14. http://dx.doi.org/10.33772/jitro.v6i1.5572.
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ABSTRAKTujuan penelitian adalah mengevaluasi level penambahan minyak ikan lemuru dalam ransum ayam kampung terhadap profil lemak darah.Materi penelitian yang digunakan adalahayam kampung betina umur 24 minggu. Bahan pakan yang digunakan adalah minyak ikan lemuru, bekatul, jagung giling, bungkil kedelai, minyak sawit, tepung ikan, dan premix multi mineral dan vitamin. Metode penelitian menggunakan rancangan acak lengkap (RAL). Perlakuan yang diberikan adalah T0 = Penggunaan minyak ikan lemuru sebanyak 0%, T1 = Penggunaan minyak ikan lemuru sebanyak 2%, T2 = Penggunaan minyak ikan lemuru sebanyak 4%, T3 = Penggunaan minyak ikan lemuru sebanyak 6%. Parameter yang diamati adalah kolesterol total, kadar High Density Lipoprotein (HDL) dan Low Density Lipoprotein (LDL) darah ayam kampung. Data dianalisis menggunakan analisis variansi yang dilanjutkan uji duncan.Hasil penelitian menunjukkan bahwa perlakuan dengan minyak ikan lemuru pada level tertinggi berpengaruhnyata (P<0,05) terhadap kolesterol total, kadar HDL dan LDL darah.Kesimpulan penelitian adalah pemberian minyak ikan lemuru sampai 6% dapat digunakan dalam campuran pakan ayam kampung.Kata kunci: Profil lemak darah, ayam lokal, minyak ikan lemuruABSTRACTThe aimed of the study was to evaluate the level of addition lemuru fish oil in the ration of local chicken on the blood fat profile. The research materials used was female local chickens aged 24 weeks. The feed materials used are lemuru fish oil, rice bran, milled corn, soybean meal, palm oil, fish meal as well as multimineral and vitamin premix. The research method using a complete by randomized design. The treatments are given wereT0= lemuru fish oil as much as 0%, T1 = lemuru fish oil as much as 2%, T2 = lemuru fish oil as much as 4%, T3 = lemuru fish oil as much as 6%. The observed variables were total cholesterol, levels of high-density lipoprotein (HDL) and low-density lipoprotein (LDL) of local chicken blood. The data were analyzed using analysis of variance and was continued with Duncan test. The results showed that the treatment with lemuru fish oil at the highest level had a significant effect (P<0.05) on total cholesterol, HDL levels, and LDL blood. The conclusion of the study is that the provision of lemuru fish oil up to 6% can be used in native chicken feed mix.Keywords: The blood fat profile, local chicken, lemuru fish oil
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Cavalleri, Chiara, Gerrit Brouwer, Dimas Kodri, David Rose, and Jan-Bart Theodoor Brinks. "Maximizing the Value of Pulsed-Neutron Logs: A Complex Case Study of Gas Pressure Assessment Through Casing." Petrophysics – The SPWLA Journal of Formation Evaluation and Reservoir Description 61, no. 6 (2020): 610–22. http://dx.doi.org/10.30632/pjv61n6-2020a6.
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Casedhole logging for formation evaluation and input to determine the redevelopment potential of an oil producer with a challenging production history was conducted. This included an intelligent assessment of formation gas pressure through casing, which was later confirmed by perforating. The target reservoirs are Triassic sandstones drilled as a gas exploration prospect. Based on openhole log data, the prospect appeared to be oil bearing. The well has been producing oil for several years and is now a candidate for a gas cap blowdown. The presence of heterogeneous layers with varied rock quality and producibility indexes coupled to complexity in fluids distribution and zonal isolation issues complicates the development process and ability to optimize recovery from any contributing level. Recently, a new-generation casedhole formation evaluation tool that provides multiple independent formation property measurements was deployed to enhance knowledge of the formation parameters while describing the current gas and oil volumes. Sigma, neutron porosity, fast-neutron cross section (FNXS), and elemental concentrations, including total organic carbon from inelastic and capture spectroscopy, were simultaneously recorded. Because the well is highly deviated in the zones of interest, the tool was efficiently conveyed on wireline using tractor technology. The evaluation techniques used to study this rich set of data reveal several pieces of information that are essential to the petrophysicists and geologists, and to the reservoir and production engineers. A multimineral solver analysis guided by the prior knowledge of the rocks using cores from offset wells was conducted to quantify the porosity and gas-oil contact levels while giving access to detailed knowledge of matrix and rock composition for refining the reservoir models. Additionally, a novel method to determine gas pressure at the current time from the casedhole log measurements was applied to support reservoir management. The highly sensitive sigma, neutron porosity, and FNXS gas properties can be parameterized as a function of pressure and temperature if the formation and fluid properties are known. This is a well-established principle that can finally be applied independently and directly to multiple measurements. The computations are done independently and checked against each other for consistency and to support optimal parameter setting, in an iterative manner. This is particularly important in this scenario where the complexity of the wellbore environment and history of the well could have complicated the ability to achieve enough precision on the estimated pressures when coming from a single method or if modeling is required. The log results, with validation, and implications for the well redevelopment are presented together with a general discussion on the methodology and applicability based on this well experience. The importance of meticulous job preparation, prejob modeling, and data quality control is also highlighted. The information is key to defining the future well development management strategy and clarify the role that casedhole logging can play as part of the complete well evaluation process.
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Alfahaid, Fahad, Shamshad Begum Loni, Mohammed Zaid Aljulifi, et al. "Multivitamin- Multimineral (MVMM) Use Among Saudi Adults In Al-Majmah, Saudi Arabia: Prevalence and associated Factors." Journal of Pioneering Medical Sciences 14, Special Issue 1 (2025): 68–76. https://doi.org/10.47310/jpms202514s0109.
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Introduction: A nutritious diet is essential for sustaining good health and preventing illness. Globally, billions of people take dietary supplements like Multivitamin-Multimineral (MVMM) preparations to improve their health, prevent diseases, or fill vitamin and mineral shortages. This current study was carried out to determine the prevalence and characteristics of Multivitamin- Multimineral (MVMM) use among Saudi populations in Al-Majmaah, Saudi Arabia. Methods: A descriptive cross-sectional study as conducted in Majmah, Saudi Arabia, where all adults age above 18 years old were enrolled in this study, data was collected by using properly designed an online survey and collected data, was analyzed using Statistical Package for Social Sciences (SPSS 24). Results: The study included 347 participants, of whom about 55% were male and 45% were female adults. Most of participants did not follow any special diets behavior, 34% had vegetables and fruits regularly and only 20% had regular physical activity. About 47% of participants (Male 46.3% and Female 53.7%, p-value .001 significant statistical relationship between genders) used vitamins and minerals in their daily life, for those who using these products, about 51% used multiple vitamins and minerals, 42% used Vit D, 7% used Folic Acid, 7% used Ferrous, 5% used Vit B and 5% used other vitamins or minerals. About 47% of participants used it daily and 34% on weekly basis. Our study found a significant statistical relationship between, age group (18-28 years; 53.7%, 29-39; 16.5%, 40-50; 26.8% and more than 50; 3.0%; p-value .009 significant statistical relationship between age groups) marital status (Married; 45.7%, Single; 45.7%, Divorced; 2.4%, Widowed; 0.6%; p-value .000 highly significant statistical relationship between marital status groups), while there was no statistical relationship between educational level groups with p-value >0.05. Conclusion: The study revealed a high prevalence of MVMM use among the general population in Saudi Arabia, reporting a significant statistical relationship with gender, age group and marital status. Most participants (more than two-thirds) thought that MVMM supplements were used to enhance health. They obtained MVMM directly from the pharmacy without a prescription, as part of a hospital prescription. These findings show the need for greater awareness on the importance of balanced nutrition and physical exercise, in addition to supplement use, in improving general well-being in the Saudi population. The study’s findings are intriguing but have limitations. Its online survey approach and Al-Majmaah City restriction could have introduced bias. Therefore, a broad population and more comprehensive methodological approaches might be used in future research.
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Lopez-Cepero, Andrea, Roxana Torres, Augusto Elias, Milagros C. Rosal, and Cristina Palacios. "Micronutrient Intake among Children in Puerto Rico: Dietary and Multivitamin-Multimineral Supplement Sources." International Journal for Vitamin and Nutrition Research 85, no. 5-6 (2015): 329–39. http://dx.doi.org/10.1024/0300-9831/a000252.
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Abstract. Background: Micronutrients are critical for healthy growth and development of children. Micronutrient intake from dietary sources is inadequate among some children and may be improved by use of multivitamin and multimineral (MVMM) supplements. Objective: To assess micronutrient intake from dietary and MVMM supplement sources among 12-year-old children in Puerto Rico. Methods: A representative sample of 732 children enrolled in an oral health study in Puerto Rico, who completed dietary and MVMM assessments through one 24-h recall, were included in this analysis. Micronutrient intake sources were described and compared to the Dietary Reference Intakes (DRIs) using the Estimated Average Requirement when available (used Adequate Intake for vitamin K and pantothenic acid). Micronutrient profiles of MVMM users and non-users were compared using t-tests. Results: Mean intakes of vitamins A, D, E, and K, pantothenic acid, calcium, and magnesium from food and beverage sources were below the DRIs. From food and beverage sources, MVMM users had higher intakes of riboflavin and folate compared to non-users (p < 0.05). When MVMM supplements were taken into account, users had higher intakes of all nutrients except vitamin K. With the help of MVMM, users increased intake of vitamins E, A, D, and pantothenic acid to IOM-recommended levels but calcium, magnesium, and vitamin K remained below guidelines. Conclusion: Micronutrient intake from diet was below the IOM-recommended levels in the total sample. MVMM use improved intake of selected micronutrients and facilitated meeting recommendations for some nutrients. Public health measures to improve micronutrient intake among children in Puerto Rico are needed.
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Robert, M., M. Hardy, and F. Elsass. "Crystallochemistry, properties and organization of soil clays derived from major sedimentary rocks in France." Clay Minerals 26, no. 3 (1991): 409–20. http://dx.doi.org/10.1180/claymin.1991.026.3.09.
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AbstractThe nature, crystallochemistry, organization and surface properties of soil clays derived from the most representative sedimentary formations of France are described, using qualitative and quantitative mineralogical methods and high resolution transmission microscopy (HRTEM). The main results show that soil clays differ significantly from reference clays. Even when 2:1 phyllosilicates are dominant, the clays always contain multimineral phases. The smectitic component is dioctahedral and of beidellite type. Soil clay organization is specific: all the clay particles have a short lateral extension and few layers (mean 5 layers, and even mono-layers occur). The superposition of such small particles leads to the formation of what are called “texturally interstratified minerals” which are dominant in soil clays. Exchange and surface properties (high ratio of external surface to total surface area), are related to clay organization.
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Gehring, A. U., and R. Karthein. "An ESR and calorimetric study of iron oolitic samples from the Northampton ironstone." Clay Minerals 25, no. 3 (1990): 303–11. http://dx.doi.org/10.1180/claymin.1990.025.3.06.
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AbstractElectron spin resonance (ESR) spectroscopy and calorimetric methods were used to characterize conversion processes in multimineral samples from the Northampton ironstone (NIS) at temperatures between 25°C and 800°C. The beginning of the thermal conversion processes can be determined by the formation of asymmetric ESR spectra with g ≈ 2 at 250°C. The breakdown of the berthierine structure between 250°C and 520°C is indicated by the disappearance of the hyperfine splitting in the Mn2+ spectrum and the formation of magnetite. The decomposition of siderite and calcite was found by calorimetric methods at 580°C and 700°C, respectively. The hematite formation between 550°C and 800°C is explained by the decomposition of siderite but also by the oxidation of previously formed magnetite. The occurrence of hematite as the dominant ferric oxide at 800°C signifies the end of the conversion process of the major mineral phases in the NIS samples.
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Bhalerao, Pramod P., and Chandrakant S. Waghmare. "Drug utilisation study in medicine outpatient department at Ashwini Rural Medical College, Kumbhari, Solapur, India." International Journal of Basic & Clinical Pharmacology 8, no. 8 (2019): 1919. http://dx.doi.org/10.18203/2319-2003.ijbcp20193203.
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Background: Drug utilization studies are used to analyze different aspects of the use of drugs and to implement methods of improving therapeutic quality. This study was conducted to study drug prescription pattern in Medicine Outpatient Department (OPD) in Ashwini Rural Medical College, Kumbhari. Methods: Six hundred prescriptions were screened & analyzed as per the study parameters at Medicine OPD of Ashwini Rural Medical College, Kumbhari. Study parameters like demographic profile of the patient like age, sex and diagnosis were recorded. Doctor details and patient details like age, sex and address were analyzed. Also, groups of drugs commonly prescribed, number of drugs per patient, drug profile and drawbacks of prescription if any were recorded and analyzed.Results: Most common group of drugs prescribed by physicians were Analgesics (21.84%), followed by Drugs for Peptic ulcer (17.92%) and Multivitamins/multimineral (14.70%). The average number of drugs prescribed per patient was 2.38. The incidence of Polypharmacy was common occurrence and some prescriptions had small drawbacks like absence of diagnosis, absence of doctor’s signature, etc.Conclusions: Authors conclude that most of the prescriptions which were analyzed at Ashwini Rural Medical College Hospital, Kumbhari, were according to the standard norms of WHO prescriptions and also most of the drugs prescribed were from the list of essential drug list. But still there is scope for improvement in prescription pattern.
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Fu, Lei, Yanxiang Yu, Chicheng Xu, et al. "Well-Log-Based Reservoir Property Estimation With Machine Learning: A Contest Summary." Petrophysics – The SPWLA Journal of Formation Evaluation and Reservoir Description 65, no. 1 (2024): 108–27. http://dx.doi.org/10.30632/pjv65n1-2024a6.
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Well logs are processed and interpreted to estimate in-situ reservoir properties, which are essential for reservoir modeling, reserve estimation, and production forecasting. While the traditional methods are mostly based on multimineral physics or empirical formulae, machine learning provides an alternative data-driven approach that requires much less a-priori geological or petrophysical information. From October 2021 to March 2022, the Petrophysical Data-Driven Analytics Special Interest Group (PDDA SIG) of the Society of Petrophysicists and Well Log Analysts (SPWLA) hosted a machine-learning contest aiming to develop data-driven models for estimating reservoir properties, including shale volume, porosity, and fluid saturation, based on a common set of well logs, including gamma ray, bulk density, neutron porosity, resistivity, and sonic. Log data from nine wells from the same field, together with the interpreted reservoir properties by petrophysicists, were provided as training data, and five additional wells were provided as blind test data. During the contest, various data-driven models were developed by the contestants to predict the three reservoir properties with the provided training data set. The top five performing models from the contest, on average, beat the performance of the benchmarked Random Forest model by 45% in the root-mean-square error (RMSE) score. In the paper, we will review these top-performing solutions, including their preprocessing techniques, feature engineering, and machine-learning models, and summarize their advantages and conditions.
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Mellal, Ilyas, Abdeljalil Latrach, Vamegh Rasouli, Omar Bakelli, Abdesselem Dehdouh, and Habib Ouadi. "Water Saturation Prediction in the Middle Bakken Formation Using Machine Learning." Eng 4, no. 3 (2023): 1951–64. http://dx.doi.org/10.3390/eng4030110.
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Tight reservoirs around the world contain a significant volume of hydrocarbons; however, the heterogeneity of these reservoirs limits the recovery of the original oil in place to less than 20%. Accurate characterization is therefore needed to understand variations in reservoir properties and their effects on production. Water saturation (Sw) has always been challenging to estimate in ultra-tight reservoirs such as the Bakken Formation due to the inaccuracy of resistivity-based methods. While machine learning (ML) has proven to be a powerful tool for predicting rock properties in many tight formations, few studies have been conducted in reservoirs of similar complexity to the Bakken Formation, which is an ultra-tight, multimineral, low-resistivity reservoir. This study presents a workflow for Sw prediction using well logs, core data, and ML algorithms. Logs and core data were gathered from 29 wells drilled in the Bakken Formation. Due to the inaccuracy and lack of robustness of the tried and tested regression models (e.g., linear regression, random forest regression) in predicting Sw as a continuous variable, the problem was reformulated as a classification task. Instead of exact values, the Sw predictions were made in intervals of 10% increments representing 10 classes from 0% to 100%. Gradient boosting and random forest classifiers scored the best classification accuracy, and these two models were used to construct a voting classifier that achieved the best accuracy of 85.53%. The ML model achieved much better accuracy than conventional resistivity-based methods. By conducting this study, we aim to develop a new workflow to improve the prediction of Sw in reservoirs where conventional methods have poor performance.
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Pillich, C., T. Bogdan, J. Landers, G. Wurm, and H. Wende. "Drifting inwards in protoplanetary discs." Astronomy & Astrophysics 652 (August 2021): A106. http://dx.doi.org/10.1051/0004-6361/202140601.
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In previous laboratory experiments, we measured the temperature dependence of sticking forces between micrometer grains of chondritic composition. The data showed a decrease in surface energy by a factor ~5 with increasing temperature. Here, we focus on the effect of surface water on grains. Under ambient conditions in the laboratory, multiple water layers are present. At the low pressure of protoplanetary discs and for moderate temperatures, grains likely only hold a monolayer. As dust drifts inwards, even this monolayer eventually evaporates completely in higher temperature regions. To account for this, we measured the tensile strength for the same chondritic material as was prepared and measured under normal laboratory conditions in our previous work, but now introducing two new preparation methods: drying dust cylinders in air (dry samples), and heating dust pressed into cylinders in vacuum (super-dry samples). For all temperatures up to 1000 K, the data of the dry samples are consistent with a simple increase in the sticking force by a factor of ~10 over wet samples. Up to 900 K super-dry samples behave like dry samples. However, the sticking forces then exponentially increase up to another factor ~100 at about 1200 K. The increase in sticking from wet to dry extends a trend that is known for amorphous silicates to multimineral mixtures. The findings for super-dry dust imply that aggregate growth is boosted in a small spatial high-temperature region around 1200 K, which might be a sweet spot for planetesimal formation.
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Li, Nianqi, Li-Yun Fu, Jian Yang, and Tongcheng Han. "On three-stage temperature dependence of elastic wave velocities for rocks." Journal of Geophysics and Engineering 18, no. 3 (2021): 328–38. http://dx.doi.org/10.1093/jge/gxab017.
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Abstract For most rocks, the typical temperature behavior of elastic wave velocities generally features a three-stage nonlinear characteristic that could be expressed by a reverse S-shape curve with two inflexion points. The mechanism regulating the slow-to-fast transition of elastic constants remains elusive. The physics of critical points seems related to the multimineral composition of rocks with differentiated thermodynamic properties. Based on laboratory experiments for several rocks with different levels of heterogeneity in compositions, we conduct theoretical and empirical simulations by nonlinear thermoelasticity methods and a S-shape model, respectively. The classical theory of linear thermoelasticity based on the Taylor expansion of strain energy functions has been widely used for crystals, but suffers from a deficiency in describing thermal-associated velocity variations for rocks as a polycrystal mixture. Current nonlinear thermoelasticity theory describes the third-order temperature dependence of velocity variations by incorporating the fourth-order elastic constants. It improves the description of temperature-induced three-stage velocity variations in rocks, but involves with some divergences around two inflexion points, especially at high temperatures. The S-shape model for empirical simulations demonstrates a more accurate depiction of thermal-associated three-stage variations of P-wave velocities. We investigate the physics of the parameters ${a_1}$ and ${b_1}$ in the S-shape model. These fitting parameters are closely related to thermophysical properties by being proportional to the specific heat and thermal conductivity of rocks. We discuss the mechanism that regulates the slow-to-fast transition in the three-stage nonlinear behavior for various rocks.
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Jiang, Yan, Xuhui Chen, Zhen Cai, Ying Yao, and Shuaiwen Huang. "Trends and Motivations in Dietary Supplement Use Among People with Diabetes: A Population-Based Analysis Using National Health and Nutrition Examination Survey Data from the 2009–2020 Period." Nutrients 16, no. 23 (2024): 4021. http://dx.doi.org/10.3390/nu16234021.
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Objectives: Dietary supplements have gained attention among people with diabetes as an alternative and complementary treatment, yet there is a limited understanding of supplement use and the motivations behind it. Methods: Data from the National Health and Nutrition Examination Survey (NHANES) from the 2009–2020 period were analyzed, including data on 5784 people with diabetes aged 20 years or older. Dietary supplement use was self-reported. Trends in supplement use were examined across three periods: 2009–2012, 2013–2016, and 2017–2020. Statistical analyses were conducted while considering NHANES’s complex survey design to provide nationally representative estimates for the general noninstitutionalized population of the United States. Results: A total of 61.72% of individuals reported using dietary supplements with a notable increase over time. Supplement users were generally older, more likely to be female, better educated, and had superior blood glucose control with lower smoking rates compared to non-users. Common supplements included multivitamins, multimineral supplements, vitamin D, calcium, zinc, vitamin C, and fish oil. Only 44.58% of individuals used dietary supplements based on medical advice, with the rest opting for self-directed usage. The primary specific health reasons for supplement use were to improve bone health and heart health and enhance the immune system. Conclusions: Dietary supplement use is prevalent among people with diabetes, and most diabetic supplement use is self-directed, which reflects a growing trend toward complementary therapies. Healthcare providers are encouraged to inquire about patients’ use of supplements and offer appropriate guidance as an integral component of comprehensive diabetes management.
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Gacek, Maria, Agnieszka Wojtowicz, and Adam Popek. "Personality Determinants Related to the Use of Selective and Effective Dietary Supplements by Elite Polish Team Sport Athletes." Sports 12, no. 1 (2024): 29. http://dx.doi.org/10.3390/sports12010029.
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Introduction: The purpose of this research was to analyse relationships between personality traits and the use of selected dietary supplements among Polish athletes training in team sports. This subject matter has not been explored in prior research. Material and Methods: This research was carried out among a group of 213 athletes (men) in the 18–36 age range, with the implementation of a proprietary validated questionnaire for the use of dietary supplements and the NEO-PI-R inventory (Neuroticism–Extraversion–Openness Personality Inventory—Revised). Statistical analyses were performed with the Kruskal–Wallis and Mann–Whitney tests, assuming the following level of significance: α = 0.05. Results: It was shown that athletes who periodically and regularly consumed isotonic drinks, as well as energy bars and gels, were characterised by a lower level of neuroticism than those who did not consume them. Athletes who periodically took multivitamin preparations were characterised by a lower level of extraversion and openness, and those periodically using multimineral preparations were characterised by a higher level of agreeableness than those who did not use these agents. Athletes not taking creatine were characterised by the lowest level of conscientiousness among the study participants. The use of protein nutrients, probiotics and caffeine was not associated with any personality traits in the athletes. Conclusions: Further relationships of the Big Five personality traits were demonstrated with the use of effective dietary supplements by athletes; the most unambiguous correlations were described for neuroticism and conscientiousness in such a way that the use of isotonic drinks, as well as energy bars and gels, was connected with a low level of neuroticism, while the use of creatine was connected with high conscientiousness.
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Ryabova, Yuliya V., Lada V. Shabardina, Aleksandr A. Keskevich, et al. "Neurotoxic effects of cadmium chloride exposure combined with physical activity and protective effect of bioprophylactic agents." Hygiene and sanitation 103, no. 2 (2024): 165–71. http://dx.doi.org/10.47470/0016-9900-2024-103-2-165-171.
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Introduction. Chemical compounds possessing of a neurotropic effect are extremely widespread in industry, which makes the problem of neurotoxicity relevant for occupational medicine. Since industrial workers are often exposed to a combination of both physical and chemical work-related risk factors, a complex adverse health effect of the latter should be considered.
 Our objective was to study neurotoxic effects of exposure to cadmium chloride combined with physical activity in a subchronic experiment on rats and assess the efficacy of a biological prophylactic complex.
 Material and methods. For six weeks, 0.77 mg/kg b.w. of cadmium chloride was intraperineally instilled to outbred male albino rats thrice a week. Five times a week, the rodents were forced to run for 10 minutes at a speed of 25 m/min. During the entire exposure period, half of the animals received a specially developed bioprophylactic complex consisting of pectin, monosodium glutamate, and a multivitamin/multimineral supplement with feed and drink.
 Results. In combination with physical activity, cadmium exposure caused depression, anxiety, low exploratory behaviour, and spatial memory disturbances. The developed bioprophylactic complex helped mitigate toxic effects of cadmium aggravated with intense physical activity and improve the general condition of the rodents.
 Limitations. The experiment was limited to examining the behaviour of male rats following subchronic exposure to a single dose of cadmium.
 Conclusions. Subchronic exposure to cadmium combined with physical activity can induce certain neurotoxic effects. Administration of the specially developed complex of biological protectors has shown to attenuate or minimize these effects. Similar measures can be taken to diminish risks of adverse health consequences of the factors studied.
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Yan, Xiaoxue, Shuaichao Wei, Wei Zhang, Feng Liu, and Yuzhong Liao. "Reservoirs and Hydrogeochemical Characterizations of the Yanggao Geothermal Field in Shanxi Province, China." Water 16, no. 5 (2024): 669. http://dx.doi.org/10.3390/w16050669.
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Geothermal water is the product of deep circulation within the crust, and the understanding of its hydrogeochemical process can provide effective information for integrated research on its circulation pattern and formation mechanism. Based on the geothermal geological conditions of the Yanggao geothermal field, this study analyzed water samples from thermal springs and geothermal wells in the geothermal field, ascertaining their hydrochemical components, along with their hydrogen and oxygen isotopes. Using methods like piper diagrams, ionic component ratio characterization, Na–K–Mg equilibrium diagrams, and reverse path simulations, this study elucidated the recharge source of geothermal water in the study area, revealed the water–rock interactions the geothermal water experienced, and evaluated the geothermal reservoir temperatures. The results show that the geothermal water has hydrochemical types of Na–Cl–HCO3 and Na–HCO3–Cl, and is primarily recharged by the atmospheric precipitation in the northern mountainous area. The geothermal water has experienced extended water runoff and deep thermal circulation, and its hydrochemical composition primarily results from the weathering and dissolution of silicate rocks and evaporites. The major hydrogeochemical processes of the geothermal water involve the dissolution of calcite, dolomite, gypsum, and kaolinite. In addition, the canon-exchange also changes the chemical component of the geothermal water. The SiO2 Geothermometer, a multimineral equilibrium diagram, and the silica–enthalpy model reveal the presence of deep and shallow geothermal reservoirs in the study area, which exhibit temperatures of 73 °C and ranging from 125 to 150 °C, respectively. The open geothermal reservoir environment results in the mixing of geothermal water and cold water, with shallow and deep geothermal water mixing with cold water at ratios of 57% and 76%, respectively.
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Afsan, Mohammad, Muhammad Mahbubul Alam, Nushrat Noor, and AH Hamid Ahmed. "Prescribing patterns of a garment medical centre in Bangladesh." Update Dental College Journal 3, no. 1 (2014): 7–11. http://dx.doi.org/10.3329/updcj.v3i1.17978.
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Objectives: The aim of the study was to audit the prescription and dispensing pattern in a garment medical center to observe the rational use of drug. Irrational use of medicine is a global problem. Polypharmacy, injudicial use of antibiotics, unnecessary use of vitamins are commonly seen in Bangladesh. To find out the current status of the prescribing and dispensing practices and identify factors underlying irrational prescription writing in a Garment medical center for factory workers in Gajipur and to sensitize the future prescribers about the rational prescriptions, this study was carried out. Materials and methods: A cross-sectional descriptive study was carried out to analyze the patterns of prescriptions by using World Health Organization , WHO/INRUD- core drug prescribing indicators and some additional indices. Place and period of study: A total of 300 prescriptions of the patients (garment workers) who had attended in Hannan Textile and Garment Medical Centre, Board Bazar, Dhaka, Bangladesh in between January and November2008 were considered for analysis. Results: The average number of drugs per prescription was 3.1 and no single drug was prescribed by generic name. Use of antibiotic (50% of encounters) was frequent. Only 50.75% drugs were prescribed from national essential drug list (EDL). Percentage of encounters with an antiulcerant, a NSAID and a multivitamin & multimineral prescribed were 41.67%, 46.67% and 23.67% respectively. Conclusion: This study revealed some of irrational practices like poly pharmacy, overuse of antibiotics and vitamins, no use of generic names, and less prescribed from essential drug list. It is suggested that the periodic evaluation of prescribing practices at the healthcare facilities should be done by proper involvement of physician, nurse and pharmacist for the rational use of medicine. DOI: http://dx.doi.org/10.3329/updcj.v3i1.17978 Update Dent. Coll. j: 2013; 3 (1): 07-11
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Pothana, Prasad, Ghoulem Ifrene, and Kegang Ling. "Integrated Petrophysical Evaluation and Rock Physics Modeling of Broom Creek Deep Saline Aquifer for Geological CO2 Storage." Fuels 5, no. 1 (2024): 53–74. http://dx.doi.org/10.3390/fuels5010004.
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Fossil fuels, such as coal and hydrocarbons, are major drivers of global warming and are primarily responsible for worldwide greenhouse gas emissions, including carbon dioxide CO2. The storage of CO2 in deep saline reservoirs is acknowledged as one of the top practical and promising methods to reduce CO2 emissions and meet climate goals. The North Dakota Industrial Commission (NDIC) recently approved the fourth Class VI permit for a carbon capture and storage project in the Williston basin of North Dakota for the geological CO2 storage in the Broom Creek formation. The current research aimed to conduct a comprehensive petrophysical characterization and rock physics modeling of the Broom Creek deep saline reservoir to unravel the mineralogical distribution and to understand the variations in petrophysical and elastic properties across the formation. This study utilized geophysical well logs, routine core analysis, and advanced core analysis to evaluate the Broom Creek formation. Multimineral petrophysical analysis calibrated with X-ray diffraction results reveals that this formation primarily comprises highly porous clean sandstone intervals with low-porosity interspersed with dolomite, anhydrite, and silt/clay layers. The formation exhibits varying porosities up to 0.3 and Klinkenberg air permeabilities up to ∼2600 mD. The formation water resistivity using Archie’s equation is approximately 0.055 ohm-m at 150 °F, corresponding to around 63,000 ppm NaCl salinity, which is consistent with prior data. The pore throat distribution in the samples from clean sandstone intervals is primarily situated in the macro-mega scales. However, the presence of anhydrite and dolomite impedes both porosity and pore throat sizes. The accurate prediction of effective elastic properties was achieved by developing a rock physics template. Dry rock moduli were modeled using Hill’s average, while Berryman’s self-consistent scheme was employed for modeling saturated moduli.
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Afsan, Mohammad, Muhammad Mahbubul Alam, Nushrat Noor, Abul Kalam Mohyammad Yousuf, and MM Ekramul Haque. "Audit of Typical Prescription Format Among the Prescribers of a Garment Medical Centre in Bangladesh." Update Dental College Journal 1, no. 2 (2013): 07–12. http://dx.doi.org/10.3329/updcj.v1i2.13979.
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Objective: To audit the typical prescription or general format according to WHO guidelines for good prescription writing.Materials and methods: A cross-sectional descriptive study was conducted after collecting data from medical records to observe standard of prescriptions and identify factors underlying inappropriate prescription writing.Place and period of study: A total of 300 prescriptions of the patients (garment workers) who had attended in Hannan Textile and Garment Medical Centre, Board Bazar, Dhaka, Bangladesh in between January and November2008 were considered for analysis. Results: Audit of the prescription pattern revealed that most of the prescriptions did not conform to the pattern of a typical prescription. The patients identity was mentioned in all prescriptions (100%). Date of the prescription and superscription symbol (Rx) were also mentioned in all prescriptions (100%). Inscription which includes name of the drug, dosage form and total amount of medication prescribed was mentioned in all prescriptions (100%) but dose and duration of treatment were mentioned in 66% and 70% prescriptions respectively. In this study, about 91.67% instructions to the pharmacist and 50% special instructions to the patient regarding the dosage form and total amount to be dispensed were found adequately. Almost 100% of the prescriptions adequately mentioned the dosage schedules and also precautions/warnings about the drug therapy. Almost 100% of the prescriptions were signed by the doctors mentioning their full name, address with qualification and registration number. But telephone/mobile number of the doctors was not found in all prescriptions (100%). Most common diagnosis among garment workers was ARI (19.33%). Most commonly prescribed group of drug was antiulcerent (17.13%) and most commonly prescribed antibiotic was amoxicillin (13.67%). Most of the drugs were prescribed in oral form (97.77%). No single drug interaction (0%) was found in any prescription. The fixed dose-drug combinations (FDCs) accounted for 67% drugs prescribed. The most commonly FDC was multivitamin and multimineral which was not included in essential medicine list (EML).Conclusion: Large numbers of prescriptions did not conform to ideal pattern and lack in their rationality. This study revealed a lot of scope for educating the prescribers to improve prescribing practices.DOI: http://dx.doi.org/10.3329/updcj.v1i2.13979 Update Dent. Coll. j. 2011: 1(2): 07-12
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Pacheva, Iliyana, and Ivan Ivanov. "Targeted Biomedical Treatment for Autism Spectrum Disorders." Current Pharmaceutical Design 25, no. 41 (2020): 4430–53. http://dx.doi.org/10.2174/1381612825666191205091312.
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Background: A diagnosis of autism spectrum disorders (ASD) represents presentations with impairment in communication and behaviour that vary considerably in their clinical manifestations and etiology as well as in their likely pathophysiology. A growing body of data indicates that the deleterious effect of oxidative stress, mitochondrial dysfunction, immune dysregulation and neuroinflammation, as well as their interconnections are important aspects of the pathophysiology of ASD. Glutathione deficiency decreases the mitochondrial protection against oxidants and tumor necrosis factor (TNF)-α; immune dysregulation and inflammation inhibit mitochondrial function through TNF-α; autoantibodies against the folate receptors underpin cerebral folate deficiency, resulting in disturbed methylation, and mitochondrial dysfunction. Such pathophysiological processes can arise from environmental and epigenetic factors as well as their combined interactions, such as environmental toxicant exposures in individuals with (epi)genetically impaired detoxification. The emerging evidence on biochemical alterations in ASD is forming the basis for treatments aimed to target its biological underpinnings, which is of some importance, given the uncertain and slow effects of the various educational interventions most commonly used. Methods: Literature-based review of the biomedical treatment options for ASD that are derived from established pathophysiological processes. Results: Most proposed biomedical treatments show significant clinical utility only in ASD subgroups, with specified pre-treatment biomarkers that are ameliorated by the specified treatment. For example, folinic acid supplementation has positive effects in ASD patients with identified folate receptor autoantibodies, whilst the clinical utility of methylcobalamine is apparent in ASD patients with impaired methylation capacity. Mitochondrial modulating cofactors should be considered when mitochondrial dysfunction is evident, although further research is required to identify the most appropriate single or combined treatment. Multivitamins/multiminerals formulas, as well as biotin, seem appropriate following the identification of metabolic abnormalities, with doses tapered to individual requirements. A promising area, requiring further investigations, is the utilization of antipurinergic therapies, such as low dose suramin. Conclusion: The assessment and identification of relevant physiological alterations and targeted intervention are more likely to produce positive treatment outcomes. As such, current evidence indicates the utility of an approach based on personalized and evidence-based medicine, rather than treatment targeted to all that may not always be beneficial (primum non nocere).
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Lee, Hyungjoo, Alexander Mitkus, Andrew Pare та ін. "A New Workflow for Estimating Reservoir Properties With Gradient Boosting Model and Joint Inversion Using MWD Measurements". Petrophysics – The SPWLA Journal of Formation Evaluation and Reservoir Description 65, № 2 (2024): 215–32. http://dx.doi.org/10.30632/pjv65n2-2024a5.
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Triple-combo logs are important measurements for estimating geological, petrophysical, and geomechanical properties. Unfortunately, wireline and advanced logging-while-drilling (LWD) logs are typically dropped from the formation evaluation plan for unconventional wells due to economic constraints or borehole instability risks. Available measurements are typically measurement-while-drilling (MWD) gamma ray (GR) logs, along with surface measurements such as weight on bit (WOB), rate of penetration (ROP), torque, rotation per minute (RPM), and differential pressure. The development of a robust and rapid model for predicting reservoir properties using this limited data set would be of high value for geological evaluation. Estimating such properties is a challenging task due to the nonlinear relationship between the available log data and unknown reservoir properties. A novel workflow that combines two sequential models is presented. First is a machine-learning (ML) algorithm to predict triple-combo logs from drilling dynamics and GR logs. To train the ML algorithm, well logs obtained from multiple wells located in the Eagle Ford and Permian Basins are scrutinized to identify important features. This process includes depth shifting, outlier detection, and feature selection, which allows for strategic hyperparameter tuning. Several regression algorithms are investigated, and it is found that gradient boosting algorithms yield superior prediction performance. Unlike random forest methods, boosting algorithms train predictors sequentially, each trying to correct its predecessor. After triple-combo logs are predicted from MWD logs, a physics-based joint inversion model is applied to estimate various reservoir properties. The trained model is deployed on a blind test well, and the predicted logs show excellent agreement compared to the corresponding triple-combo measurements. The multimineral inversion using predicted triple-combo logs yields a geologic model that is validated with elemental capture spectroscopy (ECS) measurements. Additionally, reconstructed logs from the forward model closely match measured logs by minimizing the cost function. Therefore, real-time estimated geological, petrophysical, and geomechanical properties can reveal complex geologic information and be used to mitigate uncertainty related to drilling optimization, reservoir characterization, development planning, and reserve estimation. Using the MWD logs to predict triple-combo logs followed by a joint inversion is an innovative approach for geological evaluation with a limited data set. The developed workflow can successfully provide (1) geologic lithofacies identification and rock typing, (2) more confidence in real-time drilling operation, (3) reservoir properties prediction, (4) missing log imputations and pseudo-log generation with forward modeling, (5) guidance for future logging and perforation, (6) reference for seismic quantitative interpretation (QI) and well tie, and (7) potentially massive computation time saving from days to minutes.