11351 research outputs found
Sort by
Integrating runoff generation and flow routing in Susquehanna River basin to characterize key hydrologic processes contributing to maximum annual flood events
No full textThe Susquehanna River basin (SRB) is the largest U.S. watershed (71; 250 km2) draining to the Atlantic Coast. It encompasses portions of New York, Pennsylvania, and Maryland. Given that annual maximum flood events commonly result from either rain-on-snow or hurricanes/tropical storms, determining the potential impacts of climate change on flooding behavior is especially challenging. This paper presents a modeling system that captures these dominant flooding processes, which is well-suited for future research investigating the impacts of regional climate change. For this study, a coupled hydrologic-hydraulic model is developed and used to estimate hourly streamflow for the period from 2000 to 2008, capturing a range annual maximum discharge phenomenon (e.g., rain-on-snow, localized convective events, and hurricanes/tropical storms). The three-layer variable infiltration capacity (VIC-3L) model is used to generate surface runoff and the vertical flux of water through the root zone at a scale of 0.025° (about 2.8 km), which are used as inputs to the Hillslope River Routing (HRR) model that operates on an irregular grid with a mean length scale of 4.7 km to simulate lateral surface and subsurface transport and channel hydraulics. The coupled model is validated using USGS daily streamflow, snow water equivalent (SWE) derived from the advanced microwave scanning radiometer for EOS (AMSR-E) satellite and snow depth from in situ measurements. The coupled model (VIC-HRR) shows good performance for both seasonal baseflow patterns and large flood events (e.g., rain-on-snow and hurricane/tropical storms). Given the SRB is commonly subjected to two types of flood events, the role of snow processes is investigated. Comparing synthetic model scenarios with and without snow processes suggests that if future climate conditions reduce winter snowfall due to warmer temperatures, but maintain total precipitation levels, annual runoff will increase and mean annual peak discharge will decrease
Sperm superoxide dismutase is associated with bull fertility
No full textDecreasing mammalian fertility and sperm quality have created an urgent need to find effective methods to distinguish non-viable from viable fertilising spermatozoa. The aims of the present study were to evaluate expression levels of β-tubulin 2C (TUBB2C), heat shock protein 10 (HSP10), hexokinase 1 (HXK1) and superoxide dismutase 1 (SOD1) in spermatozoa from Holstein bulls with varying fertility using western blotting and to analyse the biological networks of these key sperm proteins using a bioinformatics software (Metacore; Thomson-Reuters, Philadelphia, PA, USA). The rationales behind this study were that the sperm proteins play crucial roles in fertilisation and early embryonic development in mammals and ascertaining the biological networks of the proteins helps us better understand sperm physiology and early mammalian development. The results showed that expression of SOD1 was higher in spermatozoa from high fertility bulls (P\u3c0.05) and that SOD1 is the best protein to diagnose bulls based on the fertility index (P\u3c0.05). Using Metacore analysis, we identified an SOD1 network with pathways and linkages with other relevant molecules. We concluded that SOD1 sperm expression is associated with in vivo bull fertility. The findings are important because they illuminate molecular and cellular determinants of sperm viability and the identified protein markers can be used to determine bull fertility
The TRI-AG Academics Research Extension College Of Agriculture Sciences - Vol 2 No1 2016
Get PDFhttps://digitalcommons.pvamu.edu/pv-magazine/1006/thumbnail.jp
The TRI-AG Academics Research Extension College Of Agriculture Sciences - Vol. 2 No. 2 - 2016
Get PDFhttps://digitalcommons.pvamu.edu/pv-magazine/1012/thumbnail.jp
Effect of early pregnancy diagnosis by per rectum amniotic sac palpation on pregnancy loss, calving rates, and abnormalities in newborn dairy calves
No full textThe objectives of the present study were to evaluate the effect of per rectal amniotic sac palpation (ASP) for pregnancy diagnosis during the late embryonic period on pregnancy loss, calving rates, and abnormalities in newborn calves. A controlled, randomized, blocked, blind experiment containing 680 lactating pregnant dairy cows with a viable embryo diagnosed by transrectal ultrasonography was performed. Two dairy operation sites (farm A and farm B) were selected. At each farm, the cows were randomly divided into control (CON) and ASP groups. The CON group was not subjected to pregnancy diagnosis via per rectum palpation. The ASP examinations were performed by one experienced veterinarian between Days 34 and 45 after breeding. All cows were reevaluated by transrectal ultrasonography only between 2 and 4 weeks later. Two calving rates were calculated: calving rate 1 (cows that calved from the initial number of pregnant cows) and calving rate 2 (cows that calved from cows pregnant at reexamination). In farm A, the percentages of early pregnancy loss were 11.5% (19 of 165) and 13.2% (24 of 182) for the CON and the ASP groups, respectively (P = 0.64). In farm B, the percentage of early pregnancy loss was 11.2% (19 of 170) for the CON group and 8.8% (14 of 159; P = 0.48) for the ASP group. In farm A, the percentage of late pregnancy loss was 7.6% (11 of 145) for the CON group and 5.5% (8 of 155; P = 0.39) for the ASP group. In farm B, the percentage of late pregnancy loss was 3.7% (5 of 137) for the CON group and 6.3% (8 of 127; P = 0.32) for the ASP group. In farm A, early pregnancy loss was higher than late pregnancy loss (12.4% vs. 6.3%; P = 0.01), and in farm B, the same tendency was detected (10.0% vs. 4.9%, for early and late pregnancy loss, respectively; P = 0.02). In farm A, calving rate 1 was 81.2% (134 of 165) for the CON group and 80.8% (147 of 182; P = 0.92) for the ASP group. Calving rate 2 for the same groups was 92.4% (134 of 145) and 94.8% (147 of 155), respectively (P = 0.68). In farm B, calving rate 1 was 77.7% (132 of 170) for the CON group and 74.8% (119 of 159; P = 0.55) for the ASP group. Calving rates 2 for the same groups were 87.4% (132 of 151) and 82.1% (119 of 145), respectively (P = 0.20). Two female calves with atresia coli were diagnosed only in the CON group. It was concluded that ASP during the late embryonic period for pregnancy diagnosis did not increase the pregnancy loss, affect calving rates, or produce abnormalities in calves
Applicability of screening tests for oxytetracycline in the milk of three breeds of goats
No full textAntibiotics are widely used in animal husbandry, and the presence of antibiotic residues in milk is a health hazard. The objectives of this study were to determine residual amounts of oxytetracycline in the milk of three breeds of goats using highpressure liquid chromatography (HPLC) analysis and screening tests. It was also essential to explore the safe withdrawal period of oxytetracycline in lactating goats and examine the applicability of Charm ROSA and SNAP screening tests. The qualitative results of these tests were compared with the quantitative results of the HPLC method. Fifteen milking does, five each from the Alpine, LaMancha, and Nubian breeds, were selected from the herd at Prairie View A&M University. Milk samples containing antibiotic residues were deproteinized by HCl and acetonitrile, and then oxytetracycline was extracted from the supernatant. The residues of oxytetracycline in goat\u27s milk up to 110 h after injection were qualitatively detected using the Charm ROSA test. Similarly, the SNAP test detected the antibiotic residues in milk up to 110 h after treatment. The HPLC results indicated that oxytetracycline residues in milk from Alpine goats were below the tolerance level (300 ng/ml) 82 h after drug treatment (72 h for LaManchas, 58 h for Nubians); however, the results of the screening tests would indicate longer withdrawal periods for milk from the breeds of goats studied, which would result in economic losses to goat\u27s milk producers. The results of this study also indicated that oxytetracycline was not stable in raw goat\u27s milk at refrigeration temperature or during pasteurization and that the concentrations decreased significantly. Commercial goat\u27s milk is usually exposed to several hours of refrigeration and then to pasteurization. The results of this study indicated that, if oxytetracycline was present in raw goat\u27s milk, the concentration would decrease significantly before it was marketed
Layer-dependent energy of two parallel charged nano-layers
No full textWe consider a bilayer nanosystem consisting of two parallel charged nano-layers. Such a system represents the typical building block of a multi-layered nanostructure formed by alternatively depositing thin metal-insulator-metal layers. We calculate exactly in closed form the electrostatic interaction energy between two parallel charged nano-layers where each of them is modeled as a finite two-dimensional square-shaped system with constant surface charge density. We apply suitable mathematical transformations that allow us to derive an exact expression for the interaction energy between nano-layers as a function of both size and inter-layer separation distance. We also derive an approximate expression for the interaction energy linearized with respect to the inter-layer separation that works well for small inter-layer separation. We show that the interaction energy of this configuration of nano-layers depends on the ratio of the inter-layer separation distance relative to the characteristic length of the structure
Independent Domination in Some Wheel Related Graphs
Get PDFA set S of vertices in a graph G is called an independent dominating set if S is both independent and dominating. The independent domination number of G is the minimum cardinality of an independent dominating set in G . In this paper, we investigate the exact value of independent domination number for some wheel related graphs
Viscous Dissipation and Heat Absorption effect on Natural Convection Flow with Uniform Surface Temperature along a Vertical Wavy Surface
Get PDFThe effect of viscous dissipation and heat absorption on a steady two-dimensional natural convection laminar flow of viscous incompressible fluid with uniform surface temperature along a vertical wavy surface has been investigated. Using the appropriate variables; the basic equations are transformed to convenient form and then solved numerically employing very efficient method, namely Keller-Box method (KBM). Numerical results are presented by the shearing stress in terms of the local skin-friction coefficient; the rate of heat transfer in terms of local Nusselt number, streamline and isotherms, respectively for a wide range of the viscous dissipation parameter N and heat absorption parameter Q. Increasing Q and lessening N cause the enhancement of heat transfer rate
Chemocatalytic hydrolysis of cellulose at 37 °c, 1 atm
No full textThe metal salt-Brønsted acidic ionic liquid system composed of ZnCl2·1.74H2O-1-(1-propylsulfonic)-3-methylimidazolium chloride can directly hydrolyze untreated cellulose in 78% total reducing sugar and 19% glucose yield at 37 °C, 1 atm in 4.0 days. The new chemical catalyst is used at a temperature lower than typical cellulase enzyme operating conditions