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Changes in fetal mannose and other carbohydrates induced by a maternal insulin infusion in pregnant sheep

journal of Animal Science and Biotechnology 2015年第2期6卷 222-229页

作者： laura D Brown Stephanie R Thorn Alex Cheung jinny R Lavezzi Frederick C Battaglia Paul j Rozance Perinatal Research Center Division of Neonatology Department of Pediatrics University of Colorado Denver School of Medicine Center for Women’s Health Research University of Colorado Denver School of Medicine

Background： The importance of non-glucose carbohydrates, especially mannose and inositol, for normal development is increasingly recognized. Whether pregnancies complicated by abnormal glucose transfer to the fetus also affect the regulation of non-glucose carbohydrates is unknown. In pregnant sheep, maternal insulin infusions were used to reduce glucose supply to the fetus for both short （2-wk） and long （8-wk） durations to test the hypothesis that a maternal insulin infusion would suppress fetal mannose and inositol concentrations. We also used direct fetal insulin infusions （1-wk hyperinsulinemic-isoglycemic clamp） to determine the relative importance of fetal glucose and insulin for regulating non-glucose carbohydrates. Results： A maternal insulin infusion resulted in lower maternal （50%, P 〈 0.01） and fetal （35-45%, P 〈 0.01） mannose concentrations, which were highly correlated （r^2 = 0.69, P 〈 0.01）. A fetal insulin infusion resulted in a 50% reduction of fetal mannose （P 〈 0.05）. Neither maternal nor fetal plasma inositol changed with exogenous insulin infusions. Additionally, maternal insulin infusion resulted in lower fetal sorbitol and fructose （P 〈 0.01）. Conclusions： Chronically decreased glucose supply to the fetus as well as fetal hyperinsulinemia both reduce fetal non-glucose carbohydrates. Given the role of these carbohydrates in protein glycosylation and lipid production, more research on their metabolism in pregnancies complicated by abnormal glucose metabolism is clearly warranted.

关键词： Fructose Glucose Inositol Insulin Mannose Pregnancy

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Projected Future Wind Speed and Wind Power Density Trends over the Western US High Plains

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Atmospheric and Climate Sciences 2012年第1期2卷 32-40页

作者： j. Scott Greene Matthew Chatelain Mark morrissey Steve Stadler 不详

This manuscript presents the results of research on future changes in wind speed and wind power density across the western US High Plains in an area known for its high wind energy resources. Many current policies and economic analyses involving the rapidly expanding wind energy industry have assumed a constant or near constant wind resource. However, any future change in wind speeds will result in changes in the reliability of wind power as an energy resource. This paper uses current data (1970-2000) and future model output (2040-2070) to analyze decadal and seasonal changes in wind speed across the study area. In addition, estimated hub height wind power densities have been analyzed. Results show projections of a slight overall decreasing wind power in the future across the region. The greatest magnitude changes are estimated to be in the seasonal trends with the most substantial decreases occurring in winter and spring. As climate changes and warms overall, there will be shifts in the temperature gradients and the synoptic storm tracks that drive wind speeds. Thus, it is theorized that the wind speeds will be the result of an earlier transition to, and longer duration of, a calmer summertime pattern. This longer duration of a summertime pattern will lead to the decreased wind speeds and lower wind power output identified in this research. This decrease needs to be factored in for any estimates of the long-term costs and benefits of wind farms in the area.

关键词： Wind Climatology Renewable Energy Climatic Variability

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Parameter identification through mode isolation for reaction-diffusion systems on arbitrary geometries

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International journal of Biomathematics 2018年第4期11卷 149-178页

作者： laura Murphy Chandrasekhar Venkataraman Anotida Madzvamuse School of Mathematical and Physical SciencesUniversity of Sussex Department of Mathematics Brighton BNI 9QH UK School of Mathematics and StatisticsUniversity of St Andrews St Andrews UK School of Mathematical and Physical SciencesUniversity of Sussex Department of Mathematics Brighton BN1 9QH UK

We present a computational framework for isolating spatial patterns arising in the steady states of reaction-diffusion systems. Such systems have been used to model many nat- ural phenomena in areas such as developmental and cancer biology, cell motility and material science. In many of these applications, often one is interested in identifying parameters which will lead to a particular pattern for a given reaction-diffusion model. To attempt to answer this, we compute eigenpairs of the Laplacian on a variety of domains and use linear stability analysis to determine parameter values for the system that will lead to spatially inhomogeneous steady states whose patterns correspond to particular eigenfunctions. This method has previously been used on domains and surfaces where the eigenvalues and eigenfunctions are found analytically in closed form. Our contribution to this methodology is that we numerically compute eigenpairs on arbitrary domains and surfaces. Here we present examples and demonstrate that mode isolation is straightforward especially for low eigenvalues. Additionally, we show that in some cases the inhomogeneous steady state can be a linear combination of eigenfunctions. Finally,we show an example suggesting that pattern formation is robust on similar surfaces in cases that the surface either has or does not have a boundary.

关键词： Reaction diffusion systems finite elements parameter identification eigen-value problem.

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Fekete-Gauss Spectral Elements for Incompressible Navier-Stokes Flows:The Two-Dimensional Case

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Communications in Computational Physics 2013年第5期13卷 1309-1329页

作者： laura Lazar Richard Pasquetti Francesca Rapetti Lab.j.A.Dieudonne UMR 7351 CNRS UNSUniversite de Nice-Sophia Antipolis06108 Nice Cedex 02France

Spectral element methods on simplicial meshes,say TSEM,show both the advantages of spectral and finite element methods,i.e.,spectral accuracy and geometrical *** present a TSEM solver of the two-dimensional(2D)incompressible Navier-Stokes equations,with possible extension to the 3D *** uses a projection method in time and piecewise polynomial basis functions of arbitrary degree in *** so-called Fekete-Gauss TSEM is employed,i.e.,Fekete(***)points of the triangle are used as interpolation(***)*** the sake of consistency,isoparametric elements are used to approximate curved *** resolution algorithm is based on an efficient Schur complement method,so that one only solves for the element boundary ***,the algebraic system is never assembled,therefore the number of degrees of freedom is not *** accuracy study is carried out and results are provided for classical benchmarks:the driven cavity flow,the flow between eccentric cylinders and the flow past a cylinder.

关键词： Spectral elements simplicial meshes Fekete-Gauss approximation Navier-Stokes equations projection methods domain decomposition

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Analysis of Autopilot Disengagements Occurring During Autonomous Vehicle Testing

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IEEE/CAA journal of Automatica Sinica 2018年第1期5卷 58-68页

作者： Chen Lv Dongpu Cao Yifan Zhao Daniel j. Auger Mark Sullman Huaji Wang laura Millen Dutka Lee Skrypchuk Alexandros Mouzakitis School of Aerospace Transport and Manufacturing Cranfield University Cranfield Bedford MK430AL UK jaguar Land Rover Coventry CV3 4LF UK IEEE

In present-day highly-automated vehicles, there are occasions when the driving system disengages and the human driver is required to take-over. This is of great importance to a vehicle's safety and ride comfort. In the U.S state of California, the Autonomous Vehicle Testing Regulations require every manufacturer testing autonomous vehicles on public roads to submit an annual report summarizing the disengagements of the technology experienced during testing. On 1 january 2016,seven manufacturers submitted their first disengagement reports:Bosch, Delphi, Google, Nissan, Mercedes-Benz, Volkswagen, and Tesla Motors. This work analyses the data from these disengagement reports with the aim of gaining abetter understanding of the situations in which a driver is required to takeover, as this is potentially useful in improving the Society of Automotive Engineers(SAE) Level 2 and Level 3 automation *** events from testing are classified into different groups based on attributes and the causes of disengagement are investigated and compared in detail. The mechanisms and time taken for take-over transition occurred in disengagements are studied. Finally, recommendations for OEMs, manufacturers, and government organizations are also discussed.

关键词： Automated vehicle Disengagement humanvehicle interactions take-over operation vehicle testing

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Proximal gastric response to small intestinal nutrients is abnormal in mechanically ventilated critically ill patients

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World journal of Gastroenterology 2006年第27期12卷 4383-4388页

作者： Nam Q Nguyen Robert j Fraser Marianne Chapman laura K Bryant Richard H Holloway Rosalie Vozzo Christine Feinle-Bisset Department of Gastroenterology Hepatology and General MedicineRoyal Adelaide HospitalSouth Australia University Department of Medicine University of AdelaideSouth Australia Department of Intensive Care Royal Adelaide HospitalSouth Australia Department of Gastroenterology Hepatology and General MedicineRoyal Adelaide HospitalSouth Australia Department of GastroenterologyUniversity of AdelaideSouth Australia

AIM： To determine the response of the proxima stomach to small intestinal nutrients in critically ill patients. METHODS： Proximal gastric motility was measured in 13 critically ill patients （49.3 ± 4.7 years） and 12 healthy volunteers （27.7 ± 2.9 years） using a barostat technique. Recordings were performed at baseline, during a 60-rain intra-duodenal infusion of Ensure^R （2 kcal/min）, and for 2 h following the infusion. Minimum distending pressure （MDP）, intra-bag volume and fundic wave activity were determined. RESULTS： The MDP was higher in patients （11.7 ± 1.1 vs 7.8 ± 0.7 mmHg; P 〈 0.01）. Baseline intrabag volumes were similar in the 2 groups. In healthy subjects, a ‘bimodal＇ proximal gastric volume response was observed. In patients, the initial increase in proximal gastric volume was small and delayed, but eventually reached a maximal volume similar to that of healthy subjects. In healthy subjects, the proximal gastric volume rapidly returned to baseline level after nutrient infusion （median 18 min）. In contrast, the recovery of volume to baseline was delayed in critically ill patients （median 106 min）. In 6 patients, the volume had not returned to baseline level 2 hours after nutrient infusion. In patients, fundic volume waves were less frequent （P 〈 0.05） and had lower amplitude （P 〈 0.001）, compared to healthy subjects. CONCLUSION： In critical illness, proximal gastric motor responses to small intestinal nutrient stimulation are abnormal.

关键词： Proximal gastric response Small intestinal nutrient Critical illness

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Neutralising effects of small molecule toxin inhibitors on nanofractionated coagulopathic Crotalinae snake venoms

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Acta Pharmaceutica Sinica B 2020年第10期10卷 1835-1845页

作者： Chunfang Xie julien Slagboom laura-Oana Albulescu Govert W.Somsen Freek j.Vonk Nicholas R.Casewell jeroen Kool Amsterdam Institute of Molecular and Life Sciences Division of BioAnalytical ChemistryDepartment of Chemistry and Pharmaceutical SciencesFaculty of ScienceVrije Universiteit AmsterdamAmsterdam 1081HVThe Netherlands Centre for Analytical Sciences Amsterdam(CASA) Amsterdam 1098 XHThe Netherlands Centre for Snakebite Research and Interventions Liverpool School of Tropical MedicineLiverpool L35QAUK Centre for Drugs and Diagnostics Liverpool School of Tropical MedicineLiverpool L35QAUK Naturalis Biodiversity Center Leiden 2333 CRThe Netherlands

Repurposing small molecule drugs and drug candidates is considered as a promising approach to revolutionise the treatment of snakebite *** this study,we investigated the inhibiting effects of the small molecules varespladib(nonspecific phospholipase A2 inhibitor),marimastat(broad spectrum matrix metalloprotease inhibitor)and dimercaprol(metal ion chelator)against coagulopathic toxins found in Crotalinae(pit vipers)snake *** from Bothrops asper,Bothrops jararaca,Calloselasma rhodostoma and Deinagkistrodon acutus were separated by liquid chromatography,followed by nanofractionation and mass spectrometry identification undertaken in *** of the venom toxins were then subjected to a high-throughput coagulation assay in the presence of different concentrations of the small molecules under *** venom toxins were mostly identified as phospholipases A2,while procoagulant venom activities were mainly associated with snake venom metalloproteinases and snake venom serine *** was found to effectively inhibit most anticoagulant venom effects,and also showed some inhibition against procoagulant ***,marimastat and dimercaprol were both effective inhibitors of procoagulant venom activities but showed little inhibitory capability against anticoagulant *** information obtained from this study aids our understanding of the mechanisms of action of toxin inhibitor drug candidates,and highlights their potential as future snakebite treatments.

关键词： Snakebite Antivenom Varespladib Marimastat Dimercaprol Chelators Nanofractionation

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Atrazine removal from water by activated charcoal cloths

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International Soil and Water Conservation Research 2020年第2期8卷 205-212页

作者： javier M.Gonzalez Lynnette R.Murphy Chad j.Penn Veera M.Boddu laura L.Sanders National Soil Erosion Research Laboratory USDA-ARSWest LafayetteIN47907USA Earth Science Department Northeastern Illinois UniversityChicagoIL60625USA O’Neill School of Public and Environmental Affairs University of IndianaBloomingtonIN47405USA Plant Polymer Research Unit National Center for Agriculture Utilization ResearchUSDA-ARSPeoriaIL61604USA

Pollution control structures may be adapted to enhance the removal of nutrients and pesticides from water. Charcoal-like material is known to sorb organic compounds in solution, including atrazine, a herbicide used to control broadleaf weeds, which persists in soils and can migrate from soils to water bodies, ultimately affecting water quality. The primary goal of this study was to investigate if activated charcoal cloths (single-weave, SW;double-weave, DW;and knitted, KT) are more efficient to remove atrazine from aqueous solutions than a cloth without activated charcoal (control) currently used in pollution control structures. The approach consisted of sorption kinetics, flow-through, and desorption/degradation experiments using 50 and 1000μg L-1 atrazine solutions. Results showed that within 30 min of contact time, the control sorbed from 22.6 to 36.1% of atrazine in solution;whereas the activated charcoal cloths sorbed from 76 to 99% of atrazine in solution (SW > KT > DW). The flow-through ex-periments showed that the SW sorbed 88.2, 76.1, and 52.2%of atrazine at the contact time of 0.75, 5, and 10 min, respectively. After 28 days of incubation, previously sorbed atrazine on the SW cloth did not degrade and <2.0% was desorbed. The results showed that activated charcoal cloths are a practical alternative for improving atrazine removal in water in pollution control structures.

关键词： Atrazine Activated charcoal Water quality Pesticide Cloth

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Monitoring real time polymorphic transformation of sulfanilamide by diffuse reflectance visible spectroscopy

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journal of Pharmaceutical Analysis 2016年第3期6卷 179-183页

作者： Tracy O.Ehiwe Bruce D.Alexander john C.Mitchell Martin j.Snowden laura j.Waters Medway Centre for Formulation Science Faculty of Engineering and Science University of Greenwich at Medway School of Applied Sciences University of Huddersfield

This study investigated the development of a novel approach to surface characterization of drug poly- morphism and the extension of the capabilities of this method to perform ＇real time＇ in situ measure- ments. This was achieved using diffuse reflectance visible （DRV） spectroscopy and dye deposition, using the pH sensitive dye, thymol blue （TB）. Two polymorphs, SFN-β and SFN-γ, of the drug substance sulfanilamide （SFN） were examined. The interaction of adsorbed dye with polymorphs showed different behavior, and thus reported different DRV spectra. Consideration of the acid/base properties of the morphological forms of the drug molecule provided a rationalization of the mechanism of differential coloration by indicator dyes. The kinetics of the polymorphic transformation of SFN polymorphs was monitored using treatment with TB dye and DRV spectroscopy. The thermally-induced transformation fitted a first-order solid-state kinetic model （R2=0.992）, giving a rate constant of 2.43 × 10^- 2 s 1.

关键词： Polymorphic transformation Sulfanilamide Diffuse reflectance visible spectroscopy Powder X-ray diffraction Differential scanning calorimetry

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Glia and hemichannels: key mediators of perinatal encephalopathy

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Neural Regeneration Research 2018年第2期13卷 181-189页

作者： Robert Galinsky joanne O.Davidson justin M.Dean Colin R.Green laura Bennet Alistair j.Gunn Department of Physiology University of Auckland The Ritchie Centre Hudson Institute of Medical Research Department of Ophthalmology University of Auckland

Perinatal encephalopathy remains a major cause of disability, such as cerebral palsy. Therapeutic hypo- thermia is now well established to partially reduce risk of disability in late preterm/term infants. However, new and complementary therapeutic targets are needed to further improve outcomes. There is increasing evidence that glia play a key role in neural damage after hypoxia-ischemia and infection/inflammation. In this review, we discuss the role of astrocytic gap junction （connexin） hemichannels in the spread of neural injury after hypoxia-ischemia and/or infection/inflammation. Potential mechanisms of hemichannel medi- ated injury likely involve impaired intraceUular calcium handling, loss of blood-brain barrier integrity and release of adenosine triphosphate （ATP） resulting in over-activation of purinergic receptors. We propose the hypothesis that inflammation-induced opening of connexin hemichannels is a key regulating event that initiates a vicious cycle of excessive ATP release, which in turn propagates activation of purinergic receptors on microglia and astrocytes. This suggests that developing new neuroprotective strategies for preterm infants will benefit from a detailed understanding of glial and connexin hemichannel responses.

关键词： hypoxia-ischemia connexin hemichannels spreading injury connexin 43 astrocytes hypoxicischemic encephalopathy

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