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Proton-pump inhibitor use does not affect semen luality in subfertile men

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Asian Journal of Andrology 2018年第3期20卷 290-293页

作者： Sorena Keihani james R Craig Chong Zhang Angela P Presson Jeremy b Myers William O brant Kenneth I Aston benjamin R Emery Timothy G Jenkins Douglas T Carrell james M Hotaling Division of Urology Department of Surgery University of Utah Salt Lake City Utah 84132 USA Division of Epidemiology Department of Internal Medicine University of Utah Salt Lake City Utah 84132 USA Andrology and IVF Laboratory Department of Surgery (Urology) University of Utah Salt Lake City Utah 84108 USA

Proton-pump inhibitors （PPIs） are among the most widely used drugs worldwide. PPI use has recently been linked to adverse changes in semen quality in healthy men; however, the effects of PPI use on semen parameters remain largely unknown specifically in cases with male factor infertility. We examined whether PPI use was associated with detrimental effects on semen parameters in a large population of subfertile men. We retrospectively reviewed data from 12 257 subfertile men who had visited our fertility clinic from 2003 to 2013. Patients who reported using any PPIs for 〉3 months before semen sample collection were included; 7698 subfertile men taking no medication served as controls. Data were gathered on patient age, medication use, and conventional semen parameters; patients taking any known spermatotoxic medication were excluded. Linear mixed-effect regression models were used to test the effect of PPI use on semen parameters adjusting for age. A total of 248 patients （258 samples） used PPIs for at least 3 months before semen collection. In regression models, PPI use （either as the only medication or when used in combination with other nonspermatotoxic medications） was not associated with statistically significant changes in semen parameters. To our knowledge, this is the largest study to compare PPI use with semen parameters in subfertile men. Using PPIs was not associated with detrimental effects on semen quality in this retrospective study.

关键词： infertility proton-pump inhibitors semen analysis sperm quality spermatozoa

An Interface-Capturing Regularization Method for Solving the Equations for Two-Fluid Mixtures

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Communications in Computational Physics 2013年第10期14卷 1322-1346页

作者： Jian Du Robert D.Guy Aaron L.Fogelson Grady b.Wright james P.Keener Department of Mathematical Science Florida Institute of TechnologyMelbourneFL 32901USA Department of Mathematics University of UtahSalt Lake CityUT 84112USA Department of bioengineering University of UtahSalt Lake CityUT 84112USA Department of Mathematics University of California DavisDavisCA 95616USA Department of Mathematics Boise State UniversityBoiseID 83725USA

Many problems in biology involve gels which are mixtures composed of a polymer network permeated by a fluid solvent(water).The two-fluid model is a widely used approach to described gel mechanics,in which both network and solvent coexist at each point of space and their relative abundance is described by their volume *** phase is modeled as a continuum with its own velocity and constitutive *** some biological applications,free boundaries separate regions of gel and regions of pure solvent,resulting in a degenerate network momentum equation where the network volume fraction *** overcome this difficulty,we develop a regularization method to solve the two-phase gel equations when the volume fraction of one phase goes to zero in part of the computational domain.A small and constant network volume fraction is temporarily added throughout the domain in setting up the discrete linear equations and the same set of equation is solved *** equations are very poorly conditioned for small values of the regularization parameter,but the multigrid-preconditioned GMRES method we use to solve them is efficient and produces an accurate solution of these equations for the full range of relevant regularization parameter values.

关键词： Gel swelling preconditioner two-fluid model

A simple umbelliferone based fluorescent probe for the detection of nitroreductase

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 311-314页

作者： Adam C. Sedgwick Alex Hayden barry Hill Steven D. bull Robert b. P. Elmes Tony D. james Department of Chemistry University of Bath Bath BA2 7AY UK Department of Chemistry Maynooth University Maynooth Co. Kildare Ireland

A simple nitrobenzyl-umbelliferone （NCOU1） was synthesised containing a nitroreductase （NTR） trigger moiety. The presence of NTR, resulted in the fragmentation of the parent molecule and release of the highly emissive fluorophore umbelliferone via an NTR-catalyzed reduction of the nitro group. In the presence of the NTR enzyme, NCOU1 gave rise to a 5-fold increase in fluorescence intensity at 455 nm and was selective for NTR over other reductive enzymes. These results indicate that NCOU1 can be used as a simple assay for the detection of NTR.

关键词： fragmentation NCOU1 NTR nitroreductase nitrobenzyl-umbelliferone

bayesian Deep Learning for Dynamic Power System State Prediction Considering Renewable Energy Uncertainty

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 913-922页

作者： Shiyao Zhang james J.Q.Yu Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Department of Computer Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

Modern power systems are incorporated with distributed energy sources to be environmental-friendly and ***,due to the uncertainties of the system integrated with renewable energy sources,effective strategies need to be adopted to stabilize the entire power ***,the system operators need accurate prediction tools to forecast the dynamic system states *** this paper,we propose a bayesian deep learning approach to predict the dynamic system state in a general power ***,the input system dataset with multiple system features requires the data pre-processing ***,we obtain the dynamic state matrix of a general power system through the Newton-Raphson power flow ***,by incorporating the state matrix with the system features,we propose a bayesian long short-term memory(bLSTM)network to predict the dynamic system state variables *** results show that the accurate prediction can be achieved at different scales of power systems through the proposed bayesian deep learning approach.

关键词： bayesian deep learning data analytics NewtonRaphson power flow renewable energy source system state

Intraspecific temporal resource partitioning at white-tailed deer feeding sites

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Current Zoology 2019年第2期65卷 139-146页

作者： David b. STONE james A. MARTIN bradley S. COHEN Thomas J. PREbYL Charlie KILLMASTER Karl V. MILLER Warnell School of Forestry and Natural Resources University of Georgia Athens GA USA Savannah River Ecology Lab University of Georgia Aiken SC USA Department of biology Tennessee Technological University Cookeville TN USA Georgia Department of Natural Resources Atlanta GA USA

Individuals may reduce competition by temporally partitioning their use of a shared resource. behavioral differences between sexes in ungulates may encourage segregation as individuals attempt to avoid antagonistic interactions. However, dominant sex and age groups may reduce subordinates' access to food resources, regardless of the subordinate's sex. We hypothesized that white-tailed deer Odocoileus Virginian us temporally segregated at supplemental feedi ng sites based on social rank (subordinate: yearling males and adult females;dominant: adult males) and that segregation was affected by phase of the breeding season and diel cycle. If deer temporally segregate according to social rank, we predicted that the resulting activity patterns would manifest in one social class being relatively more susceptible to hunter-induced mortality. We used a multistate modeling approach to quantify temporal segregation and calculated the probability that a feeding site was in a particular state during diurnal and nocturnal hours for each of the 3 phases of the breeding season. We determined that transition probabilities differed by season and diel cycle and dominant and subordinate social classes clearly avoided each other, with breedi ng seas on, the probability of a subordi nate being present during diurnal hours was *** more likely than a dominant being present, but did not differ during nocturnal hours. There was no difference for dominants and subordinates during diurnal or no cturnal hours during the breedi ng season .In the post-breedi ng season, subordi nates were 1.7x more likely to occur at the feeding site than a dominant during diurnal hours but they did not differ during nocturnal hours. Our results indicate that dominance status influences temporal segregation at feeding sites and is affected by the phase of the breeding season. Therefore, the resulti ng activity patterns may in crease subordi nates' risk to human

关键词： competition multistate modeling predation risk supplemental feeding sites intraspecific temporal resource partitioning white-tailed deer

Physiological Responses of Contrasting Rice Genotypes to Salt Stress at Reproductive Stage

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Rice science 2019年第4期26卷 207-219,I0001页

作者： Maria Elisa b.GERONA Marjorie P. DEOCAMPO james A.EGDANE Abdelbagi M.ISMAIL Maribel L. DIONISIO-SESE Division of Natural Sciences and Mathematics University of the Philippines Visayas Tacloban College Leyte 6500 the Philippines Institute of biological Sciences University of the Philippines Los Banos CollegeLaguna 4031 the Philippines International Rice Research Institute DAPO Box 7777Metro Manilathe Philippines

Salinity is a major abiotic stress affecting plant growth and productivity. Considerable genetic variation is present in rice in response to salt stress, with higher sensitivity during early seedling and reproductive stage. In this study, physiological changes in leaves and developing panicles of rice genotypes (IR686, Sadri, Rc222, CSR28, IR670 and Pokkali) contrasting in salt tolerance at the reproductive stage were evaluated in greenhouse experiment under salt stress. The results showed that IR670 and the tolerant-check Pokkali maintained lower Na^+/K^+ ratio, less reduction in chlorophyll concentration, lower malondialdehyde (MDA) production, higher concentrations of reduced ascorbate (reduced AsA), higher proline accumulation and lower percentage reduction in pollen viability than the salt-sensitive genotypes under salt stress. The higher concentration of reduced AsA suggests an efficient ROS-scavenging system. Physiological measurements and pollen viability analysis revealed that Sadri (moderately tolerant at the seedling stage) is sensitive to salt stress at the flowering stage. The findings will be useful in breeding salt tolerant varieties at both seedling and reproductive stages by selecting appropriate genotypes and phenotypes.

关键词： Na^+/K^+ ratio proline reproductive stage rice salinity stress reduced ascorbate pollen viability

The Interaction of Spinach Nitrite Reductase with Ferredoxin： A Site-Directed Mutation Study

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Molecular Plant 2009年第3期2卷 407-415页

作者： Masakazu Hirasawa Jatindra N. Tripathy Ramasamy Somasundaram Michael K. Johnson Megha bhalla james R Allen David b. Knaff Department of Chemistry and biochemistry Texas Tech University Lubbock TX 79409-1061 USA Department of Chemistry University of Georgia Athens GA 30602 USA Department of Chemistry and biochemistry Arizona State University Tempe AZ 85287-1604 USA Institute for biotechnology and Genomics Texas Tech University Lubbock TX 79409-1061 USA

A series of site-directed mutants of the ferredoxin-dependent spinach nitrite reductase has been characterized and several amino acids have been identified that appear to be involved in the interaction of the enzyme with ferredoxin. In a complementary study, binding constants to nitrite reductase and steady-state kinetic parameters of site-directed mutants of ferredoxin were determined in an attempt to identify ferredoxin amino acids involved in the interaction with nitrite reductase. The results have been interpreted in terms of an in-silico docking model for the 1：1 complex of ferredoxin with nitrite reductase.

关键词： Electron transport enzymology nitrogen metabolism molecular biology.

Flow and heat transfer of a nanofluid through a porous medium due to stretching/shrinking sheet with suction,magnetic field and thermal radiation

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Applied Mathematics(A Journal of Chinese Universities) 2023年第3期38卷 373-391页

作者： Ubaidullah Yashkun Khairy Zaimi Suliadi Firdaus Sufahani Mohamed reid Mohammad Ferdows Centre of Excellence for Social Innovation and Sustainability Institute of EngineeringUniversiti Malaysia PerlisPauh Putra Campus02600ArauPerlisMalaysia Department of Mathematics Sukkur IBA UniversityAirport RoadSukkur65200SindhPakistan Department of Mathematics and Statistics Faculty of Applied Sciences and TechnologyUniversiti Tun Hussein Onn MalaysiaJohorMalaysia Department of Mathematics Faculty of ScienceNew Valley UniversityAl-Wadi Al-GadidAl-Kharga 72511Egypt Mathematics Department Faculty of ScienceNorthern Border UniversityArar 1321Saudi Arabia Research Group of Fluid Flow Modeling and Simulation Department of Applied MathematicsUniversity of DhakaDhaka-1000Bangladesh

This study investigates the suction and magnetic field effects on the two-dimensional nanofluid flow through a stretching/shrinking sheet at the stagnation point in the porous medium with thermal *** governing partial differential equations(PDEs)are converted into ordinary differential equations(ODEs)using the similarity *** resulting ODEs are then solved numerically by using the bvp4c solver in MATLAb *** was found that dual solutions exist for the shrinking parameter values up to a certain *** numerical results obtained are compared,and the comparison showed a good agreement with the existing results in the *** governing parameters’effect on the velocity,temperature and nanoparticle fraction fields as well as the skin friction coefficient,the local Nusselt number and the Sherwood number are represented graphically and *** variation of the velocity,temperature and concentration increase with the increase in the suction and magnetic field *** seems that the thermal radiation effect has increased the local Sherwood number while the local Nusselt number is reduced with it.

关键词： stagnation point flow nanofluid porous medium suction magnetohydrodynamic thermal radiation

Genetic mapping of QTL for agronomic traits and grain mineral elements in rice

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The Crop Journal 2019年第4期7卷 560-572页

作者： Gwen Iris Descalsota-Empleo Amery Amparado Mary Ann Inabangan-Asilo Frances Tesoro james Stangoulis Russell Reinke b.P.Mallikarjuna Swamy Strategic Innovation Platform International Rice Research Institute (IRRI) Metro Manila 1226 Philippines Department of Plant breeding and Genetics College of Agriculture University of Southern Mindanao Kabacan 9407 Cotabato Philippines College of Science and Engineering Flinders University Adelaide 5001 Australia

Malnutrition is one of the prevailing health problems worldwide, affecting a large proportion of the populations in rice-consuming countries. breeding rice varieties with increased concentrations of elements in the grain is considered the most cost-effective approach to alleviate malnutrition. Development of molecular markers for high grain concentrations of essential elements, particularly Zn, for use in marker-assisted selection (MAS) can hasten breeding efforts to develop rice varieties with nutrient-dense grain. We performed QTL mapping for four agronomic traits: days to 50% flowering, plant height, number of tillers, grain yield, and 13 grain elements: As, b, Ca, Co, Cu, Fe, K, Mg, Mn, Mo, Na, P, and Zn, in two doubled-haploid populations derived from the crosses IR64 × IR69428 and bR29 × IR75862. These populations were phenotyped during 2015DS and 2015WS at IRRI, Los ba os, The Philippines, and genotyped them with a 6 K SNP chip. Inclusive composite interval mapping revealed 15 QTL for agronomic traits and 50 QTL for grain element concentration. Of these, eight QTL showed phenotypic variance of >25% and 11 QTL were consistent across seasons. There were seven QTL co-localization regions containing QTL for more than two traits. Twenty five epistatic interactions were detected for two agronomic traits and seven mineral elements. Several DH lines with high Fe and Zn in polished rice were identified. These lines can be used as donors for breeding high-Zn rice varieties. Some of the major QTL can be further validated and used in MAS to improve the concentrations of nutritive elements in rice grain.

关键词： Rice Quantitative trait loci biofortification Mineral elements DH Epistasis