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Root overlap and allocation of above- and belowground growth of European beech in pure and mixed stands of Douglas fir and Norway spruce

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Forest Ecosystems 2024年第5期11卷 591-602页

作者： Amani S.Lwila Christian Ammer Oliver Gailing Ludger Leinemann Martina mun Department of Silviculture&Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077GöttingenGermany Center for Biodiversity and Sustainable Land-Use University of GöttingenBüsgenweg 137077GöttingenGermany Department of Forest Genetics and Forest Tree Breeding Faculty of Forest Sciences and Forest EcologyUniversity of GöttingenBüsgenweg 237077GöttingenGermany Forestry Research and Competence Centre Gotha Jägerstraße 1D-99867Germany

Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed ***,mechanisms that may contribute to this effect are rarely studied,even though they are essential to assess the potential of species to cope with climate *** study examined fine root overlap and the linkage between fine root and stem growth of European beech(Fagus sylvatica)growing in pure and mixed stands with Douglas fir(Pseudotsuga menziesii)or Norway spruce(Picea abies)at two different study sites in northwestern *** study sites represented substantially different soil and climate *** each site,three stands,and at each stand,three pairs of trees were *** the pure beech stand,the pairs consisted of two beech trees,while in the mixed stands each pair was composed of a beech tree and a *** each pair,three evenly spaced soil cores were taken monthly throughout the growing *** the pure beech stands,microsatellite markers were used to assign the fine roots to individual *** in stem diameter of beech were quantified and then upscaled to aboveground wood productivity with automatic high-resolution circumference *** found that fine root overlap between neighboring trees varied independently of the distance between the paired trees or the stand types(pure versus mixed stands),indicating that there was no territorial *** wood productivity(wood NPP)and fine root productivity(root NPP)showed similar unimodal seasonal patterns,peaking in ***,this pattern was more distinct for root NPP,and root NPP started earlier and lasted longer than wood *** influence of site conditions on the variation in wood and root NPP of beech was stronger than that of stand *** NPP was,as expected,higher at the richer site than at the poorer *** contrast,root NPP was higher at the poorer than at the richer *** concluded that beech can respond to limited resources

关键词： Fine root growth Stem growth Trade-off Cost-benefit ratio Belowground territoriality Conspecific neighbors Heterospecific neighbors

Rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center:Value of tailored peri-pancreatectomy protocols

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World journal of Gastrointestinal Surgery 2024年第3期16卷 681-688页

作者： Shamir O Cawich elijah Dixon Parul j Shukla Shailesh V Shrikhande Rahul R Deshpande Fawwaz Mohammed Neil W Pearce Wesley Francis Shaneeta johnson johann Bujhawan Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Faculty of MedicineUniversity of CalgaryCalgaryAlberta T2N2T9Canada Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065United States Department of Surgical Oncology Tata Memorial CenterHomi Bhabha National UniversityMumbai 400012India Department of Surgery Manchester Royal InfirmaryManchester M139WLUnited Kingdom University Surgical Unit Southampton General HospitalSouthampton SO166YDUnited Kingdom Department of Surgery University of the West IndiesNassau N-1184Bahamas Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Department of Surgery General Hospital in Port of SpainPort of Spain 000000Trinidad and Tobago

BACKGROUND Pancreaticoduodenectomy(PD)is a technically complex operation,with a re-latively high risk for *** ability to rescue patients from post-PD complications is as a recognized quality *** protocols were instituted at our low volume facility in the year *** To document the rate of rescue from post-PD complications with tailored protocols in place as a measure of *** A retrospective audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in Trinidad and Tobago between january 1,2013 and june 30,***-dardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications,and the modified Clavien-Dindo classification was used to classify post-PD *** Over the study period,113 patients at a mean age of 57.5 years(standard deviation[SD]±9.23;range:30-90;median:56)underwent PDs at this *** complications were recorded in 33(29.2%)patients at a mean age of 53.8 years(SD:±7.9).Twenty-nine(87.9%)patients who experienced major morbidity were salvaged after aggre-ssive treatment of their ***(3.5%)died from bleeding pseudoaneurysm(1),septic shock secondary to a bile leak(1),anastomotic leak(1),and myocardial infarction(1).There was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores≤2(93.3%vs 25%;P=0.0024).CONCLUSION This paper adds to the growing body of evidence that volume alone should not be used as a marker of quality for patients requiring *** low volumes at our facility,we demonstrated that 87.9%of patients were rescued from major *** attributed this to several factors including development of rescue protocols,the competence of the pancreatic surgery teams and continuous,and adaptive learning by the entire institution,cul-minating in the development of tailored peri-pancreatectomy protoc

关键词： Pancreas Complication Rescue Failure Morbidity Mortality Pancreaticoduodenectomy

Estimating geographic variation of infection fatality ratios during epidemics

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Infectious Disease Modelling 2024年第2期9卷 634-643页

作者： joshua Ladau Eoin L.Brodie Nicola Falco Ishan Bansal elijah B.Hoffman Marcin P.joachimiak Ana M.Mora Angelica M.Walker Haruko M.Wainwright Yulun Wu Mirko Pavicic Daniel jacobson Matthias Hess james B.Brown Katrina Abuabara Departments of Computational Precision Health and Dermatology University of CaliforniaSan FranciscoCA94115USA Arva Intelligence Inc.Salt Lake CityUT84101USA Computational Biosciences Group Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Earth and Environmental Sciences Area Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Graduate Group in Biostatistics University of CaliforniaBerkeleyCA94720USA Biosystems Data Science Environmental Genomics and Systems BiologyLawrence Berkeley National LaboratoryBerkeleyCA94720USA Center for Environmental Research and Community Health(CERCH) School of Public HealthUniversity of CaliforniaBerkeleyCA94720USA Bredesen Center for Interdisciplinary Research and Graduate Education University of TennesseeKnoxvilleTN37996USA Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyBostonMA02139USA Biosciences Oak Ridge National LaboratoryOak RidgeTN37830USA University of California DavisCA95616USA Statistics Department University of CaliforniaBerkeleyCA94720USA Division of Epidemiology and Biostatistics University of California Berkeley School of Public Health2121 Berkeley WayBerkeleyCA94720USA

Objectives We aim to estimate geographic variability in total numbers of infections and infection fatality ratios(IFR;the number of deaths caused by an infection per 1,000 infected people)when the availability and quality of data on disease burden are limited during an *** We develop a noncentral hypergeometric framework that accounts for differential probabilities of positive tests and reflects the fact that symptomatic people are more likely to seek *** demonstrate the robustness,accuracy,and precision of this framework,and apply it to the United States(U.S.)COVID-19 pandemic to estimate county-level SARS-CoV-2 *** The estimators for the numbers of infections and IFRs showed high accuracy and precision;for instance,when applied to simulated validation data sets,across counties,Pearson correlation coefficients between estimator means and true values were 0.996 and 0.928,respectively,and they showed strong robustness to model *** the county-level estimators to the real,unsimulated COVID-19 data spanning April 1,2020 to September 30,2020 from across the U.S.,we found that IFRs varied from 0 to 44.69,with a standard deviation of 3.55 and a median of *** The proposed estimation framework can be used to identify geographic variation in IFRs across settings.

关键词： Infection fatality ratio Infection fatality rate Noncentral hypergeometric distribution COVID-19 SARS-CoV-2

Symplectic feedback using Hamiltonian Lie algebra and its applications to an inverted pendulum

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控制理论与应用（英文版） 2013年第2期11卷 275-281页

作者： j. Lorca ESPIRO C. munoz POBLETE Departamento de Ciencias Fisicas Facultad de Ingenieria Ciencias y Administracion Universidad de La FronteraAvenida Francisco Salazar 01145 Casilla 54-D Temuco Chile Departamento de Ingenieria Electrica Facultad de Ingenieria Ciencias y Administracion Universidad de La FronteraAvenida Francisco Salazar 01145 Casilla 54-D Temuco Chile

From the symplectic representation of an autonomous nonlinear dynamical system with holonomic con- straints, i.e., those that can be represented through a symplectic form derived from a Hamiltonian, we present a new proof on the realization of the symplectic feedback action, which has several theoretical advantages in demonstrating the uniqueness and existence of this type of solution. Also, we propose a technique based on the interpretation, construction and character- ization of the pull-back differential on the symplectic manifold as a member of a one-parameter Lie group. This allows one to synthesize the control law that governs a certain system to achieve a desired behavior; and the method developed from this is applied to a classical system such as the inverted pendulum.

关键词： Hamiltonian systems Symplectic structures Lie algebra Nonlinear dynamical systems Geometric con-trol

A method to evaluate REE-HFSE mineralised provinces by value creation potential, and an example of application: Gardar REE-HFSE province, Greenland

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Geoscience Frontiers 2020年第6期11卷 2141-2156页

作者： Graham j.Banks Símun D.Olsen Antonio Gusak Geological Survey of Denmark and Greenland Øster Voldgade 10DK-1350CopenhagenDenmark Permanent Address:Route to Reserves Ulriksdalvej 13Valby2500CopenhagenDenmark University of Copenhagen Øster Voldgade 10DK-1350CopenhagenDenmark

The rare earth elements and high-field-strength elements(REE-HFSE)exploration sector conducts most evaluations at deposit and smaller *** is not evident how the sector performs a preceding exploration stage—rating and prioritising REE-HFSE mineralised provinces—to determine which provinces are prospective enough to warrant *** we present an objective,repeatable,low-cost method to screen any REE-HFSE province,as a foundation for district-scale investigations or asset *** is original for REE-HFSE screening,and adapted from regional scale copper,cobalt and petroleum exploration,and CO2 storage,screening *** is centred upon a mineralised province’s favourability for potential value creation,and to identify:(a)its main information gaps;(b)its weakest links;(c)its exploration maturity and remaining potential category;(d)how it compares against other REE-HFSE provinces;and(e)if further investigation is *** method incorporates geoscience,strategy,economic and socio-environmental factors in a way that is understandable and directly usable across stakeholder *** workflow is systematic,yet flexible enough to accommodate organisationspecific criteria,and usable for other *** provides the platform to build a global REE-HFSE province map and database consistently across national boundaries and *** for the extent of province exploration maturity and remaining mineral potential are *** illustrate the applicability of these methods using the Gardar REE-HFSE Province(GRHP)of south *** conclude that it is a moderate size,frontier province that is currently of questionable favourability for value *** move GRHP into a positive favourability class,its current weak links need strengthening by research,government policy and industry stakeholders:evaluate the mineral system;integrate all information geospatially and place it in the public domain;help the region improve some communi

关键词： REE HFSE Province Screening Favourability Value

Production systems and important antimicrobial resistant-pathogenic bacteria in poultry:a review

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journal of Animal Science and Biotechnology 2023年第2期14卷 481-500页

作者： Philip H.W.Mak Muhammad Attiq Rehman elijah G.Kiarie Edward Topp Moussa S.Diarra Guelph Research and Development Centre Agriculture and Agri-Food Canada(AAFC)GuelphONCanada Department of Animal Biosciences University of GuelphGuelphONCanada London Research and Development Center AAFCLondonONCanada.

Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and *** have been used not only for the treatment and prevention of such diseases,but also for growth ***,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the *** break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’***,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut *** Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,***)and Gram-positive(Enterococcus spp.,Staphylococcus *** ***)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised *** this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.

关键词： Antibiotic-free Antimicrobial resistance Conventional feeding Organic Poultry

Right trisegmentectomy with thoracoabdominal approach after transarterial embolization for giant hepatic hemangioma

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World journal of Gastroenterology 2009年第27期15卷 3437-3439页

作者： Hyung-Il Seo Hong jae jo mun Sup Sim Suk Kim Department of Surgery Postgraduate School of Medicine and Medical Research Institute Pusan National UniversityBusan 602-739 South Korea Department of Radiology Postgraduate School of Medicine Pusan National UniversityBusan 602-739 South Korea

Hepatic hemangiomas need to be treated surgically in cases where they are accompanied with symptoms, have a risk of rupture, or are hardly distinguishable from malignancy. The present authors conducted embolization of the right hepatic artery one day before an operation for a huge hemangioma accompanied with symptoms and confirmed a decrease in its size. The authors performed a right trisegmentectomy through a j-shape incision, using a thoracoabdominal approach, and safely removed a giant hemangioma of 32.0 cm × 26.5 cm × 8.0 cm in size and 2300 g in weight. Even for inexperienced surgeons, a j-shape incision with a thoracoabdominal approach is considered a safe and useful method when right-side hepatectomy is required for a large mass in the right liver.

关键词： Hemangioma Transarterial embolization Thoracoabdominal approach

Impact of xylanases on gut microbiota of growing pigs fed corn-or wheat-based diets

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Animal Nutrition 2018年第4期4卷 339-350页

作者： Zhengxiao Zhang Hein M.Tun Ru Li Beatriz j.M.Gonzalez Hannah C.Keenes Charles M.Nyachoti elijah Kiarie Ehsan Khafipour Department of Animal Science University of Manitoba Department of Medical Microbiology and Infectious Diseases University of Manitoba Department of Animal Bioscience University of Guelph

This study investigated the effects of xylanase supplementations with cereal-based diets on nutrient digestibility and gut microbiota of growing pigs. A total of 96 individually penned pigs(initial BW = 22.7 ± 0.65 kg) were allotted to 12 treatments and subjected to a completely randomized block design experiment. Pigs in each treatment were fed an isocaloric wheat-based or corn-based diet with or without 1 of 5 types of xylanase supplements(XA, XB, XC, XD, XE). On d 42, all piglets were euthanized to obtain ileal and cecal digesta for microbial analysis, which involved high-throughput sequencing of the V1 - V3 regions of 16 S rRNA gene. Corn-and wheat-based diets differed(P munity. Among xylanases, only XC within the wheat-based diet altered(P jority

关键词： Piglets Microbiota Xylanase Arabinoxylans Digestibility

Analysis of core protein clusters identifies candidate variable sites conferring metronidazole resistance in Helicobacter pylori

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Gastroenterology Report 2019年第1期7卷 42-49,I0002页

作者： Eng-Guan Chua Aleksandra W.Debowski KMary Webberley Fanny Peters Binit Lamichhane mun-Fai Loke jamuna Vadivelu Chin-Yen Tay Barry j.Marshall Michael j.Wise The Marshall Centre for Infectious Diseases Research and Training University of Western AustraliaPerthWestern AustraliaAustralia School of Biomedical Sciences Faculty of Health and Medical SciencesUniversity of Western AustraliaPerthWestern AustraliaAustralia Department of Medical Microbiology University of MalayaKuala LumpurWilayah PersekutuanMalaysia Shenzhen Dapeng New District Kuichong People Hospital ShenzhenGuangdongChina UM Marshall Centre University of MalayaKuala LumpurWilayah PersekutuanMalaysia School of Computer Science and Software Engineering University of Western AustraliaPerthWestern AustraliaAustralia

Background:Metronidazole is one of the first-line drugs of choice in the standard triple therapy used to eradicate Helicobacter pylori ***,the global emergence of metronidazole resistance in Hp poses a major challenge to health *** of RdxA is known to be a major mechanism of conferring metronidazole resistance in ***,metronidazole resistance can also arise in *** strains expressing functional RdxA protein,suggesting that there are other mechanisms that may confer resistance to this ***:We performed whole-genome sequencing on 121 *** clinical strains,among which 73 were ***-alignment analysis of core protein clusters derived from clinical strains containing full-length RdxA was *** sites in each alignment were statistically compared between the resistant and susceptible groups to determine candidate genes along with their respective amino-acid changes that may account for the development of metronidazole resistance in ***:Resistance due to RdxA truncation was identified in 34%of metronidazole-resistant *** of core protein clusters derived from the remaining 48 metronidazole-resistant strains and 48 metronidazole-susceptible identified four variable sites significantly associated with metronidazole *** sites included R16H/C in RdxA,D85N in the inner-membrane protein RclC(HP0565),V265I in a biotin carboxylase protein(HP0370)and A51V/T in a putative threonylcarbamoyl–AMP synthase(HP0918).Conclusions:Our approach identified new potential mechanisms for metronidazole resistance in *** that merit further investigation.

关键词： Helicobacter pylori metronidazole antibiotic resistance whole-genome sequencing core protein clusters sequence alignment