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Rapid accessibility evaluation for ballistic lunar capture via manifolds: A Gaussian process regression application

Astrodynamics 2022年第4期6卷 375-397页

作者： Sandeep K.Singh john l.Junkins Manoranjan Majji Ehsan Taheri Department of Aerospace Engineering Texas A&M UniversityCollege StationTX 77843USA Department of Aerospace Engineering Auburn UniversityAuburnAL 36849USA

In this study,a supervised machine learning approach called Gaussian process regression(GPR)was applied to approximate optimal bi-impulse rendezvous maneuvers in the cis-lunar *** demonstrate the use of the GPR approximation of the optimal bi-impulse transfer to patch points associated with various invariant manifolds in the cis-lunar *** proposed method advances preliminary mission design operations by avoiding the computational costs associated with repeated solutions of the optimal bi-impulsive lambert transfer because the learned map is computationally *** approach promises to be useful for aiding in preliminary mission *** use of invariant manifolds as part of the transfer trajectory design offers unique features for reducing propellant consumption while facilitating the solution of trajectory optimization *** ballistic capture coasts are also very attractive for mission guidance,navigation,and control robustness.A multi-input single-output GPR model is presented to represent the fuel costs(in terms of theΔV magnitude)associated with the class of orbital transfers of interest *** developed model is also proven to provide efficient *** multi-resolution use of local GPRs over smaller sub-domains and their use for constructing a global GPR model are also *** of the unique features of GPRs is that they provide an estimate of the quality of approximations in the form of covariance,which is proven to provide statistical consistency with the optimal trajectories generated through the approximation *** numerical results demonstrate our basis for optimism for the utility of the proposed method.

关键词： Gaussian process regression supervised learning invariant manifolds ballistic transfers Bayesian inference

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Intermittent suckling with or without comingling of non-littermate piglets before weaning improves piglet performance in the immediate post-weaning period when compared with conventional weaning

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Journal of Animal Science and Biotechnology 2017年第3期8卷 721-732页

作者： Diana l.Turpin Pieter langendijk Kate Plush john R.Pluske School of Veterinary and life Sciences Murdoch UniversityMurdochWA 6150Australia Trouw Nutrition Veerstraat 38Boxmeer 5831 iNThe Netherlands South Australian Research and Development Institute Roseworthy CampusJS Davis BuildingRoseworthySA 5371Australia Present address:SunPork Farms 563 Coleman RoadPinkerton PlainsSA 5400Australia

Background： In this experiment, intermittent suckling（IS） with or without the co-mingling（Co M） of piglets was studied as a method to stimulate solid feed intake and reduce post-weaning ***： Three weaning regimes using 30 multiparous sows were compared：（1） conventional weaning（CW）（n = 10 litters）, where piglets had continuous access to the sow until weaning（d 0, farrowing = d-25 relative to weaning）;（2） intermittent suckling（IS）（n = 10 litters）, where piglets were separated from the sow for 8 h/d starting at d-7（relative to weaning）; and（3） intermittent suckling with co-mingling（ISCo）（n = 10 litters） where IS started at d-7 and two litters were housed together during separation and then returned to their original sow. Ad libitum creep feed was available from d-17. At weaning pigs were housed in pens of 11 pigs, 27 pens in total. The ISCo treatment was divided in half to examine effects of different mixing strategies after weaning. Half of the ISCo litters were kept in familiar groups（ISCo F, familiar, n = 4） and the other half were mixed within treatment resulting in groups of unfamiliar pigs（ISCo NF, not familiar, n = 5）, the same as IS（n = 9） and CW（n = 9） ***： The ISCo piglets ate more creep feed in the week before weaning（P 〈 0.01）, but also showed more aggressive and manipulative behaviour on first day of Co M compared with CW piglets（P 〈 0.05）. IS with or without Co M increased exploratory and play behaviour on the first day of treatment intervention（P 〈 0.001） and increased sleeping behaviour on the last day of treatment intervention compared with CW（P 〈 0.001）. Mixing strategy at weaning had an effect on performance data with the highest growth and feed intake seen in ISCo F pigs 2 to 8 d after weaning（P 〈0.001）. IS and ISCo NF pigs also grew faster and ate more than CW pigs 2 to 8 d after weaning（P 〈 0.001）. Post-weaning injury scores suggested reduced aggression in ISCo as evidenced by reduced redness（skin irritation）（P 〈 0.05）, a

关键词： Behaviour Co-mingling Intermittent suckling Piglet Weaning

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Bile acid receptors and signaling crosstalk in the liver, gut and brain

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liver Research 2021年第3期5卷 105-118页

作者： Jessica M.Ferrell john Y.l.Chiang Integrative Medical Sciences Northeast Ohio Medical UniversityRootstownOHUSA

Bile acids are physiological detergents derived from cholesterol that aid in digestion and nutrient ab-sorption,and they play roles in glucose,lipid,and energy metabolism and in gut microbiome and metabolic *** acids mediate crosstalk between the liver and gut through bactericidal modulation of the gut microbiome,while gut microbes influence the composition of the circulating bile acid *** research indicates bile acids may also be important mediators of neurological disease by acting as peripheral signaling molecules that activate bile acid receptors in the blood-brain barrier and in the brain *** review highlights the role of bile acids in maintaining liver and gut microbe homeostasis,as well as their function as mediators of cellular signaling in the liver-gut-brain axis.

关键词： Bile acid metabolism Farnesoid X receptor(FXR) Gut-brain axis Microbiome Neurodegenerative disease Takeda G protein-coupled receptor(TGR5)

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Growth, Development and Yield of Kenaf as Affected by Planting Dates and N Fertilization

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Open Journal of Applied Sciences 2024年第3期14卷 707-720页

作者： Julius Yirzagla Peter Quandahor Iddrisu Yahaya Olivia Aguriboba Akanbelum listowell Aditwin Akologo john Bokaligidi lambon Abdul-Wahab M. Imoro Kwadwo Gyasi Santo CSIR-SARI Nyankpala Ghana St Vincent College of Education Yendi Ghana Gbewaah College of Education Pusiga-Bawku Ghana CSIR-Head Office Accra Ghana C.K. Tedam University of Technology and Applied Sciences Navrongo Ghana University of Energy and Natural Resources Sunyani Ghana

Kenaf (Hibiscus cannabinus l) consists of various beneficial components like stalks, seeds, leaves, fibers, oils, proteins, allelopathic chemicals, and fiber strands, among other things. Despite the numerous uses of the crop, there is little or no information on optimum agronomic practices such as planting date and N fertilization of the crop in the Upper East Region (UER) of Ghana where the crop is widely cultivated by smallholder farmers. Field experiments were therefore carried out in 2020 and repeated during the 2021 cropping season in the study area. The objective of the study was to determine appropriate planting date and N fertilization for increased kenaf productivity. In each year, the treatments consisted of 3 × 5 factorial combinations of three planting dates (1st July, 7th July and 14th July) and five levels of N (0, 20, 40, 60 and 80 kg/ha) replicated three times. The design of the experiment was a split-plot with the N fertilizer as the main plot and the planting date assigned to sub plot. The results showed that, planting kenaf in early (1st) July or N fertilization at the rate of 60 kg/ha increased plant density, stem height, stem diameter, dry bast and core yields in both cropping seasons.

关键词： Growth Fibres Bast Yield Core Yield

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Prostaglandin E1 administration post liver transplantation and renal outcomes:A retrospective single center experience

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World Journal of Transplantation 2024年第4期14卷 101-109页

作者： Vinay Jahagirdar Mohamed Ahmed Ifrah Fatima Hassam Ali laura Alba john H Helzberg lee S Cummings Matthew Wilkinson Jameson Forster Alisa likhitsup Department of Internal Medicine Saint Luke’s Health System of Kansas City and the University of Missouri-Kansas CityKansas CityMO 64111United States Department of Gastroenterology and Hepatology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Division of Internal Medicine Department of Gastroenterology and HepatologySaint Luke’s Health System of Kansas City and University of Missouri-Kansas CityKansas CityMO 64111United States Department of Surgery University of Missouri-Kansas City and Transplant SurgerySaint Luke’s Hospital of Kansas CityKansas CityMO 64111United States Department of Gastroenterology and Hepatology University of MichiganAnn ArborMI 48109United States

BACKGROUND Prostaglandin E1(PGE1),or alprostadil,is a potent vasodilator that improves hepatic blood flow and reduces ischemia-reperfusion injury post-liver transplantation(lT).However,the benefits of PGE1 on renal function after lT have not yet been well *** To assess the impact of PGE1 administration on renal function in patients who underwent liver or liver-kidney *** This retrospective study included all patients who underwent liver or liverkidney transplant at our institution from January,2011 to December,*** were classified based on whether they received ***1 was administered post-lT to those with transaminases>1000 U/l in the immediate postoperative ***,post-lT treatments and/or complications,renal function,and survival were *** logistic regression analysis was performed,and a two-tailed P valuelly *** A total of 145 patients underwent lT,with 44(30%)receiving *** patient characteristics were comparable,except the PGE1 group had significantly higher aspartate aminotransferase(AST)(1961.9 U/l±1862.3 U/l vs 878 U/l±741.4 U/l,P=0.000),alanine aminotransferase(1070.6 U/l±895 U/l vs 547.7 U/l±410 U/l,P=0.000),international normalized ratio on post-lT day 1(2±0.74 vs 1.8±0.4,P=0.03),a longer intensive care unit stay(8.1 days±11.8 days vs 3.8 days±4.6 days,P=0.003),more vasopressor use(55.53 hours±111 hours vs 16.33 hours±26.3 hours,P=0.002),and higher immediate postoperative complications(18.6%vs 4.9%,P=0.04).The PGE1 group also had a significantly higher 90-day readmission rate(29.6%vs 13.1%,P=0.02)and lower 1-year liver graft survival(87.5%vs 98.9%,P=0.005).However,30-day readmission(31.6%vs 27.4%,P=0.64),lT complications(hepatic artery thrombosis,biliary complications,rejection of liver graft,cardiomyopathy),1-year patient survival(96.9%vs 97.8%,P=0.77),overall liver graft survival,and overall patient survival were similar between t

关键词： liver transplantation Alprostadil Protective agents Transplant Prostaglandin E1

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Effects of vertical position on trematode parasitism in larval anurans

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Current Zoology 2019年第6期65卷 657-664页

作者： Jacob R.JONES Camille l.STEENROD john A.MARINO Jr. Biology Department Bradley UniversityPeoriaILUSA Department of Geography University of MarylandCollege ParkMDUSA

Spatial distributions of animals can affect interactions with their natural enemies,such as parasites,and thus have important implications for host-parasite *** spatial variation in infection risk has been explored in many systems at the landscape scale,less attention has been paid to spatial structure at smaller ***,we explore a hypothesized relationship between a common spatial variable,vertical position,and risk of parasite infection in a model aquatic system,larval frogs(Rana)and trematode(Digenea)*** position is relevant to this system given evidence that the densities of snail first intermediate hosts,tadpole second intermediate hosts,and trematode infective stages can vary with *** test the effects of depth on infection risk of larval frogs by trematodes,we performed two enclosure experiments,one in the laboratory and one in the field,in which larval frogs in cages just below the water surface or near the bottom of the water column were exposed to *** with near-surface cages,mean infection load(number of cysts)in tadpoles in near-bottom cages was 83%higher after 48-h exposures in the laboratory and 730%higher after 10-day exposures in the *** findings thus indicate that infection risk depends on depth,which may have adaptive significance,as tadpoles have previously been shown to change vertical position in response to parasite *** results motivate future work examining vertical variation in infection risk and may have broader implications for host-parasite dynamics and evolution of host and parasite behavior.

关键词： avoidance behavior cercariae Echinostomatidae host-parasite interactions Rana spatial structure

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Gastrointestinal tract(gut) health in the young pig

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Animal Nutrition 2018年第2期4卷 187-196页

作者： john R.Pluske Diana l.Turpin Jae-Cheol Kim School of Veterinary and life Sciences Murdoch University Pork Innovation Western Australia(Inc.) AB Vista Asia Pte.ltd

An optimally functioning gastrointestinal tract(GIT) clearly is of importance to the overall metabolism,physiology, disease status and performance of pigs of all stages of growth and ***, the‘health’ of the GIT(‘gut health’) has attracted much attention despite the lack of a clear definition to the term or its aetiology, although in broad terms, ‘gut health’ encompasses a number of physiological and functional features including nutrient digestion and absorption, host metabolism and energy generation, a stable and appropriate microbiota/microbiome, defence mechanisms including barrier function and mucosal immune mechanisms, and the interactions between these components.‘Gut health’ in the newlyweaned(young) pig is of obvious interest due to changes in GIT structure and function associated with the post-weaning transition, and more recently to the upsurge in interest in different feed additives as dietary alternatives/replacements caused by bans/reductions in certain antimicrobial compounds being available in some parts of the *** the presence of enteric disease(s) after weaning, a deterioration in ‘gut health’ may be synonymous to the overall health of the pig, and although some direct relationships can be drawn between pig performance and efficiency and a ‘healthy' GIT, sometimes this connection is subtler and less obvious, especially in the absence of overt enteric disease(s).The factors and conditions involved in ‘gut health’ are multifactorial, complex, often poorly described and sometimes incorrectly interpreted,although it is evident that perturbations of the GIT can cause an imbalance and disturb the generalized *** addition to any enteric diseases or conditions that might arise as a result of these disturbances, other influences will also impact such as the responses occurring in the GIT in the period immediately after weaning, any changes that might occur after a change in diet, and(or) disruptions to meal patterns and hence

关键词： Gastrointestinal tract Gut health Structure and function Pig Piglet Weaning

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Expanding beyond endoscopy: A review of non-invasive modalities in Barrett’s esophagus screening and surveillance

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World Journal of Gastroenterology 2022年第32期28卷 4516-4526页

作者： Dariush Shahsavari Praneeth Kudaravalli john Erikson l Yap Kenneth J Vega Division of Gastroenterology and Hepatology Augusta University-Medical College of GeorgiaAugustaGA 30912United States

Barrett’s esophagus(BE)is a condition that results from replacement of the damaged normal squamous esophageal mucosa to intestinal columnar mucosa and is the most significant predisposing factor for development of esophageal *** guidelines recommend endoscopic evaluation for screening and surveillance based on various risk factors which has limitations such as invasiveness,availability of a trained specialist,patient logistics and ***-nasal endoscopy is a less invasive modality but still has similar limitations such as limited availability of trained specialist and ***-endoscopic modalities,in comparison,require minimal intervention,can be done in an office visit and has the potential to be a more ideal choice for mass public screening and surveillance,particularly in patents at low risk for *** include newer generations of esophageal capsule endoscopy which provides direct visualization of BE,and tethered capsule endomicroscopy which can obtain high-resolution images of the *** cell collection devices coupled with biomarkers have been used for BE ***,in combination with TFF3,as well as EsophaCap and EsoCheck have shown promising results in various studies when used with various *** modalities including circulatory microRNAs and volatile organic compounds that have demonstrated favorable *** of these cell collection methods for BE surveillance is a potential area of future research.

关键词： Barrett’s esophagus Screening Surveillance Non-endoscopic Cytosponge Esophacap Esocheck

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HPlC-UV法测定银杏内酯A、B、C

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天津中医药 2024年第9期41卷 1182-1186页

作者：胡哲铭皮紫月 john OSIlAMA THOMAS 郭盼天津中医药大学现代中药发现与制剂技术教育部工程中心天津301617

[目的]建立高效液相色谱-紫外检测器(HPlC-UV)法测定银杏内酯A、B、C的浓度,并对其进行方法学验证。[方法]考察了包括检测波长、8种不同的流动相体系及其比例、进样量、流速和柱温。方法验证涵盖了专属性、精密度、准确度、线性范围、... 详细信息

[目的]建立高效液相色谱-紫外检测器(HPlC-UV)法测定银杏内酯A、B、C的浓度,并对其进行方法学验证。[方法]考察了包括检测波长、8种不同的流动相体系及其比例、进样量、流速和柱温。方法验证涵盖了专属性、精密度、准确度、线性范围、重复性、系统适用性、加样回收率和稳定性。[结果]色谱柱为Agilent TC-5 C_(18),检测波长为220 nm,流动相为水-甲醇(70∶30),进样量为20μl,柱温30℃,流速为1.0 ml/min且线性关系良好,色谱峰之间无互相干扰。[结论]该方法准确、有效,经济且易得,操作简单,为其他银杏内酯药物含量测定提供了可靠的参考。

关键词：银杏内酯高效液相色谱方法学验证

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The effect of social context and social scale on the perception of relationships in monk parakeets

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Current Zoology 2015年第1期61卷 55-69页

作者： Elizabeth A. HOBSON Darlene J. john Tiffany l. MCINTOSH Michael l. AVERY Timothy F. WRIGHT National Institute for Mathematical and Biological Synthesis University of Tennessee Knoxville TN 37996-3410 USA Department of Biology New Mexico State University Las Cruces NM 88003USA USDA Wildlife Services National Wildlife Research Center Gainesville FL 32641USA

Social relationships formed within a network of interacting group members can have a profound impact on an indi- vidual＇s behavior and fitness. However, we have little understanding of how individuals perceive their relationships and how this perception relates to our external measures of interactions. We investigated the perception of affiliative and agonistic relation- ships at both the dyadic and emergent social levels in two captive groups of monk parakeets （Myiopsitta monachus, n = 21 and 19） using social network analysis and playback experiments. At the dyadic social scale, individuals directed less aggression to- wards their strong affiliative partners and more aggression towards non-partner *** the emergent social scale, there was no association between relationships in different social contexts and an individual＇s dominance rank did not correlate with its popularity rank. Playback response pattems were mainly driven by relationships in affiliative social contexts at the dyadic scale. In both groups, individual responses to playback experiments were significantly affected by strong affiliative relationships at the dyadic social scale, albeit in different directions in the two groups. Response pattems were also affected by affiliative relation- ships at the emergent social scale, but only in one of the two groups. Within affiliative relationships, those at the dyadic social scale were perceived by individuals in both groups, but those at the emergent social scale only affected responses in one group. These results provide preliminary evidence that relationships in affiliative social contexts may be perceived as more important than agonistic relationships in captive monk parakeet groups. Our approach could be used in a wide range of social species and comparative analyses could provide important insight into how individuals perceive relationships across social contexts and social scales [Current Zoology 61 （1）： 55-69, 2015].

关键词： Affiliative Agonistic Dominance Eigenvector centrality Emergent social property Myiopsitta monachus Parrot Popularity Rank Social network analysis

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