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International journal of Biomathematics 2019年第1期12卷 1-31页

作者： R.Ishwariya j.j.h.miller S.Valarmathi Department of Mathematics Bishop Heber College TiruchirappalliTamil NaduIndia Institute for Numerical Computation and A nalysis Dublin Ireland

In this paper,a class of linear parabolic systems of singularly perturbed second-order differential equations of reaction-diffusion type with initial and Robin boundary conditions is *** components of the solution u→ of this system are smooth,whereas the components of αu→/αx exhibit parabolic boundary layers.A numerical method composed of a classical finite difference scheme on a piecewise uniform Shishkin mesh is *** method is proved to be first-order convergent in time and essentially first-order convergent in the space variable in the maximum norm uniformly in the perturbation parameters.

关键词： Singular perturbations boundary layers linear parabolic differential equations Robin boundary conditions finite difference schemes Shishkin meshes parameter uniform convergence

AN ACCURATE NUMERICAL SOLUTION OF A TWO DIMENSIONAL hEAT TRANSFER PROBLEM WITh A PARABOLIC BOUNDARY LAYER

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journal of Computational Mathematics 1998年第1期16卷 27-39页

作者： C.Clavero j.j.h.miller E.O'Riordan G.I.Shishkin Universidad de Zaragoza 西班牙 Trinity College 爱尔兰 Dublin City University 爱尔兰 Institute of Mathematics and Mechanics 俄罗斯

A singularly perturbed linear convection-diffusion problem for heat transfer in two dimensions with a parabolic boundary layer is solved numerically The numerical method consists of a special piecewise uniform mesh condensing in a neighbourhood of the parabolic layer and a standard finite difference operator satisfying a discrete maximum principle. The numerical computations demonstrate numerically that the method is epsilon-uniform in the sense that the Fate of convergence and error constant of the method are independent of the singular perturbation parameter epsilon. This means that no matter how small the singular perturbation parameter epsilon is, the numerical method produces solutions with guaranteed accuracy depending solely on the number of mesh points used.

关键词： linear convection-diffusion parabolic layer piecewise uniform mesh finite difference

Analytic and Experimental Studies of the Errors in Numerical Methods for the Valuation of Options

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Numerical Mathematics(Theory,Methods and Applications) 2008年第2期1卷 150-164页

作者： P.Lin j.j.h.miller G.I.Shishkin Department of Mathematics National University of Singapore Department of Mathematics Trinity College Dublin Institute for Mathematics and Mechanics Russian Academy of Science Ekaterinburg

The value of a European option satisfies the Black-Scholes equation with appropriately specified final and boundary *** transform the problem to an initial boundary value problem in dimensionless *** are two parameters in the coefficients of the resulting linear parabolic partial differential *** a range of values of these parameters,the solution of the problem has a boundary or an initial *** initial function has a discontinuity in the first-order derivative,which leads to the appearance of an interior *** construct analytically the asymptotic solution of the equation in a finite *** on the asymptotic solution we can determine the size of the artificial boundary such that the required solution in a finite domain in x and at the final time is not affected by the ***,we study computationally the behaviour in the maximum norm of the errors in numerical solutions in cases such that one of the parameters varies from finite (or pretty large) to small values,while the other parameter is fixed and takes either finite (or pretty large) or small values. Crank-Nicolson explicit and implicit schemes using centered or upwind approximations to the derivative are *** present numerical computations,which determine experimentally the parameter-uniform rates of *** note that this rate is rather weak,due probably to mixed sources of error such as initial and boundary layers and the discontinuity in the derivative of the solution.

关键词： Options singularities finite difference methods monotone robust method

Dietary supplementation of valine,isoleucine,and tryptophan may overcome the negative effects of excess leucine in diets for weanling pigs containing corn fermented protein

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journal of Animal Science and Biotechnology 2025年第1期16卷 267-281页

作者： Andrea P.Mallea Charmaine D.Espinosa Su A Lee Minoy A.Cristobal Leidy j.Torrez‑Mendoza hans h.Stein Division of Nutritional Sciences University of IllinoisUrbanaIL 61801USA Department of Animal Sciences University of IllinoisUrbanaIL 61801USA Present Address:EnviroFlight RaleighNCUSA.

Background Diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin ***,we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val,Trp,and(or)*** Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with 4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were *** additional diets were formu-lated by fortifying the basal diet with 20%CFP with Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-phase feeding program was used,with d 1 to 14 being phase 1 and d 15 to 28 being phase *** scores were recorded every other *** samples were collected on d 14 and 28 from one pig per *** d 14,fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial *** pigs were also euthanized and ileal tissue was *** There were no effects of dietary treatments on any of the parameters evaluated in phase *** of 10%or 20%CFP in diets reduced(Pht on d 28,and average daily gain(ADG)and average daily feed intake(ADFI)in phase 2 and for the entire experimental ***,pigs fed the CFP diet supplemented with Val,Ile,and Trp had final body weight,ADFI,ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control *** scores in phase 2 were reduced(P<0.05)if CFP was *** Corn fermented protein may be included by up to 20%in diets for weanling pi

关键词： Branched-chain amino acids Corn fermented protein Leucine Tryptophan Valine Weanling pigs

Changes in the liver transplant evaluation process during the early COVID-19 era and the role of telehealth

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World journal of Transplantation 2025年第2期15卷 149-160页

作者： Ashley h jowell Allison j Kwong Reshma Reguram Tami j Daugherty Paul Yien Kwo Department of Medicine Duke University Medical CenterDurhamNC 27710United States Department of Medicine Stanford UniversityRedwood CityCA 94063United States Department of Medicine Trinity HealthPontiacMI 48341United States

BACKGROUND Coronavirus disease 2019(COVID-19)disrupted healthcare and led to increased telehealth *** explored the impact of COVID-19 on liver transplant evaluation(LTE).AIM To understand the impact of telehealth on LTE during COVID-19 and to identify disparities in outcomes disaggregated by sociodemographic *** This was a retrospective study of patients who initiated LTE at our center from 3/16/20-3/16/21(“COVID-19 era”)and the year prior(3/16/19-3/15/20,“pre-COVID-19 era”).We compared LTE duration times between eras and explored the effects of telehealth and inpatient evaluations on LTE duration,listing,and pretransplant *** One hundred and seventy-eight patients were included in the pre-COVID-19 era cohort and one hundred and ninety-nine in the COVID-19 era *** percent(58/199)of COVID-19 era initial LTE were telehealth,compared to 0%(0/178)*** were more inpatient evaluations during COVID-19 era(40%vs 28%,Phealth use for initial LTE during COVID-19 era did not impact likelihood of listing,pretransplant mortality,or time to LTE and *** times to LTE and listing during COVID-19 were shorter than pre-COVID-19,driven by increased inpatient *** factors were not predictive of *** COVID-19 demonstrates a shift to telehealth and inpatient *** does not impact LTE or listing duration,likelihood of listing,or mortality,suggesting telehealth may facilitate LTE without negative outcomes.

关键词： Liver transplant evaluation Telehealth health access health equity COVID-19

Identifying suitable areas for plenter forest management

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Forest Ecosystems 2025年第01期 83-92页

作者： Mathias Leiter Christoph Pucher Michael Kessler Ferdinand h?nigsberger Manfred j.Lexer harald Vacik hubert hasenauer Institute of Silviculture University of Natural Resources and Life Sciences (BOKU) Institute of Forest Engineering University of Natural Resources and Life Sciences (BOKU)

Plenter forests, also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests. They are considered as an adaptation option to mitigate climate change effects. In this study, we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria, the south-eastern Province of Austria. The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management. For each 1 ha forest pixel, we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir, and at least one additional shade tolerant tree species. The technical-economic constraints are defined by slope(≤30%) and distance to the next forest road(≤100 m) to ensure cost-efficient harvesting. The results show that under current climate conditions 28.1% or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management. For the years 2071–2100 and under the climate change scenario RCP 4.5, the potential area decreases to 286,098 ha(26.3% of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1% of the total forest area). The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands, while in the higher elevations silver fir is likely to expand. Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance, resilience, and biodiversity under climate change.

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Clinical,laboratory,and therapeutic differences between immunoglobulin E-mediated and non-immunoglobulin E-mediated cow’s milk protein allergy in children

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World journal of Clinical Pediatrics 2025年第1期14卷 78-92页

作者： hasan M Isa Marwa j Abdulnabi Nawra S Naser Fatema N Lahmda Noor M AlAnsari Zahra h Isa Afaf M Mohamed Department of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Department of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Faculty of Medicine Mansoura UniversityMansoura 35516Egypt Public health Directorate Ministry of HealthManama 26671Bahrain

BACKGROUND Although breast milk is ideal for newborns,in some cases,it is replaced with cow’s milk,which contains proteins that increase the risk of cow’s milk protein allergy(CMPA).AIM To evaluate CMPA prevalence in Bahrain and compare clinical characteristics of children with immunoglobulin E(IgE)-and non-IgE-mediated *** This retrospective cohort study examined children with CMPA diagnosed at the pediatric gastroenterology outpatient clinic of the Salmaniya Medical Complex,Bahrain,between 2014 and 2022,and assessed CMPA *** presentations,laboratory findings,dietary modifications,and outcomes were compared between children with IgE-mediated and non-IgE-mediated *** variables were compared using Fisher’s exact test or Pearson’sχ2 test,whereas continuous variables were compared using Student’s t-test or the Mann-Whitney U *** Of 8332 patients,6022(72.3%)adhered to their *** them,618(10.3%)were suggested of having CMPA and 595(96.3%)were included;CMPA prevalence was 2%.Most patients were Bahraini(93.8%)and males(55.3%).Non-IgE-mediated type accounted for 77.3%cases and IgE-mediated type,22.7%.IgE-mediated CMPA presented more in boys(P=0.030),and later in life(5.1 months±4.5 months vs 4.2 months±4.2 months,P=0.016,95%CI:0.08-1.73),had more associated diseases(Ph more cutaneous(P=0.024)and respiratory(P=0.003)manifestations,severe symptoms[rash/dry skin(P=0.031),facial swelling/angioedema(P=0.003),failure to thrive(P=0.013),apparent life-threatening event(Physical findings(P=0.002)than non-IgE-mediated *** patients were exclusively fed cow milk formula(50.3%).The amino acid-based formula(AAF)was most prescribed(60.5%)with no difference between the two types(P=0.173).Although breastfeeding was recommended to 49.6%,only 8.2%were exclusively ***-mediated CMPA was associated with a longer follow-up duration than non-IgE-mediated CMPA(17.3 months±14.0 mo

关键词： Children Milk allergy Immunoglobulin E Breastfeeding Infant formula Bahrain

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn j.W.So Konstantin Feinberg Marina Manoraj jenny Cheung jennifer Zhang Kaveh Mirmoeini jPaul Santerre Tessa Gordon Gregory hBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Concentration and retention of ascorbic acid,carotenoids,and sugars in fresh-cut lettuce in modified atmosphere packaging

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horticultural Plant journal 2025年第1期11卷 303-313页

作者： jinita Sthapit Kandel Ivan Simko Ryan j.hayes Beiquan Mou U.S.Department of Agriculture Agricultural Research ServiceSam Farr United States Crop Improvement and Protection Research Center1636 E.Alisal StreetSalinasCA93905USA U.S.Department of Agriculture Agricultural Research ServiceForage Seed and Cereal Research Unit3450 SW Campus WayCorvallisOR97331USA U.S.Department of Agriculture Agricultural Research ServiceSunflower and Plant Biology Research1616 Albrecht Blvd NFargoND58102USA

Fresh-cut lettuce is widely used in ready-to-eat salads sold in modified atmosphere packages (MAP).Even in MAP,fresh-cut lettuce has short shelf life that results in loss of *** cultivars exhibit genetic variation for shelf life in MAP,but their variation for nutrient retention is not *** accessions were evaluated for initial content of ascorbic acid (AsA),carotenoids,and sugars and their retention in *** with high content and/or good retention of one or more nutrients were *** romaine accession ‘Floricos’ had high levels of all the three *** with relatively high retention of all the three nutrients were ‘Salinas 88’,‘Siskiyou’,‘Solar’,SM09A,‘Romance’,and ‘Green Towers’.Romaine cultivars,‘Balady Barrage’,‘Green Towers’,and ‘Darkland’ had relatively high initial levels of all tested nutrients and good rate of their *** was no clear correlation between initial AsA/carotene concentrations and their retention rates,suggesting that besides content,retention of nutrients should also be a breeding target in a lettuce nutritional improvement *** analyses with the Pearson's correlation coefficient determined a negative relationship between tissue deterioration(AUDePS) and retention of all tested nutrients[r of-0.52 (Phat an increase in tissue deterioration intensifies nutrient ***-sense heritability (h^(2)) across the experiments was0.15 for AsA,0.23 for total carotene,and 0.50 for total *** of germplasm with high nutrient content,extended shelf life and good nutrient retention provides valuable information for the lettuce industry and associated breeding programs.

关键词： Lettuce Shelf life Nutrient retention Ascorbic acid Carotene Sugars

Implementation of a double trigger condition system based on charge comparison and TOF measurement for the NEDA detector array

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Nuclear Science and Techniques 2025年第2期36卷 40-48页

作者： j.M.Deltoro A.Goasduff F.j.Egea V.González A.Gadea R.M.Pérez-Vidal I.Lazarus M.Kogimtzis L.McNicholl M.Palacz G.jaworski j.j.Valiente-Dobón j.Nyberg S.Casans A.E.Navarro-Antón E.Sanchis A.Boujrad E.Clément T.hüyük R.Illicachi O.Stezowski V.Modamio Department of Electronic Engineering University of ValenciaBurjassotValenciaSpain Istituto Nazionale di Fisica Nucleare Laboratori Nazionali di LegnaroLaboratori Nazionali di LegnaroLegnaroPadovaItaly Instituto de Física Corpuscular CSIC-Universidad de ValenciaCSIC-Universidad de Valencia46980 PaternaValenciaSpain Science and Technology Facilities Council DaresburyUK heavy Ion Laboratory University of Warsaw02-093 WarsawPoland Department of Physics and Astronomy Uppsala UniversityUppsalaSweden Grand Accélérateur National d’Ions Lourds(GANIL) CEA/DRF-CNRS/IN2P3CEA/DRF-CNRS/IN2P3CaenFrance Universitéde Lyon UniversitéLyon-1CNRS/IN2P3UMR5822IP2IIP2I4 Rue Enrico Fermi69622 Villeurbanne CedexFrance Department of Physics University of Oslo0316 OsloNorway

The NEutron Detector Array(NEDA)is designed to be coupled to gamma-ray spectrometers to enhance the sensitivity of the setup by enabling reaction channel selection through counting of the evaporated *** article presents the implementation of a double trigger condition system for NEDA,which improves the acquisition of neutrons and reduces the number of gamma rays *** independent triggers are generated in the double trigger condition system:one based on charge comparison(CC)and the other on time-of-flight(TOF).These triggers can be combined using OR and AND logic,offering four distinct trigger *** developed firmware is added to the previous one in the Virtex 6 field programmable gate array(FPGA)present in the system,which also includes signal processing,baseline correction,and various trigger logic *** performance of the trigger system is evaluated using data from the E703 experiment performed at *** four trigger modes are applied to the same data,and a subsequent offline analysis is *** is shown that most of the detected neutrons are preserved with the AND mode,and the total number of gamma rays is significantly *** with the CC trigger mode,the OR trigger mode allows increasing the selection of *** addition,it is demonstrated that if the OR mode is selected,the online CC trigger threshold can be raised without losing neutrons.

关键词： Neutron detector Neutron-gamma discrimination Pulse shape analysis Time-of-flight Charge comparison