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Tree community composition,structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

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Journal of Mountain science 2021年第9期18卷 2315-2327页

作者： JIMÉNEZ-PAZ Rosa WORTHY samantha J VALENCIA Renato PÉREZÁlvaro J REYNOLDs Alex BARONE John A burgess kevin s Laboratorio de Ecología de Plantas Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador Department of Biology College of Letters&SciencesColumbus State UniversityColumbusGeorgia 31907USA Herbario QCA Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador The Lovett school AtlantaGeorgia 30327USA

The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they ***,these forests grow on steep slopes that lead to dramatic habitat gradients across short *** extreme habitat gradients make the Andean forest ecosystem an excellent natural laboratory for understanding the effect of elevation on forest community diversity,structure and *** established 31 plots(50 m×5 m)which are divided between two elevational transects in the cloud forest of the siempre Verde Reserve in the western foothills of the Andes Mountains of northern *** trees and tree ferns with a diameter at breast height(dbh)≥5 cm were measured and *** examined changes in community composition,structure,and diversity along and between the elevational transects and three elevational zones:low(2437–2700 m),middle(2756–3052 m),and high(3163–3334 m).We found four main trends associated with the elevational gradients at this site:(1)community composition differed between the two transects and among the three elevational zones according to N-MDs,ANOsIM,and percentage of shared species,with some species having limited distributions,(2)metrics of community structure showed opposite relationships with elevation,depending on the transect,with the only significant relationship(negative)found between basal area and elevation in the open trail transect,(3)alpha diversity,in general,peaked at mid-elevations,and(4)beta diversity consistently increased with distance between plots along *** complexity of changes in community composition,structure,and alpha diversity along elevation may be related to the heterogeneity of the environment on a local scale,such as topography,soil composition,and even human impact,or to dispersal limitation and should be investigated *** changes in community composition and the relatively high beta diversity found at this site exemplify the biological complexity of mon

关键词： Elevational gradient Cloud forest Andes structure Composition Diversity

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Genetic analyses of ancient tea trees provide insights into the breeding history and dissemination of Chinese Assam tea(Camellia sinensis ***)

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Plant Diversity 2024年第2期46卷 229-237页

作者： Miao-Miao Li Muditha K.Meegahakumbura Moses C.Wambulwa kevin s.burgess Michael Möller Zong-Fang shen De-Zhu Li Lian-Ming Gao CAs Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of ScienceKunming650201China Germplasm Bank of Wild species Kunming Institute of BotanyChinese Academy of ScienceKunming650201China Kunming College of Life science University of Chinese Academy of SciencesKunming650201YunnanChina Department of Export Agriculture Faculty of Animal Science and Export AgricultureUva Wellassa UniversityBadulla90000Sri Lanka Department of Life sciences School of Science and ComputingSouth Eastern Kenya University170-90200KituiKenya Department of Biology Columbus State UniversityUniversity System of GeorgiaColumbusGA31907-5645USA Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburghEH35LRScotlandUK Lijiang Forest Biodiversity National Observation and Research station Kunming Institute of BotanyChinese Academy of SciencesLijiang674100YunnanChina

Chinese Assam tea(Camellia sinensis ***)is an important tea crop with a long history of cultivation in Yunnan,*** its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain *** address this issue,we genotyped 469 ancient tea plant trees representing 26 *** *** populations,plus two of its wild relatives(six and three populations of *** and ***,respectively)using 16 nuclear microsatellite *** showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(s)=0.638)than the wild relative ***(H_s=0.658).Clustering in sTRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific *** Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic ***,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene *** addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and *** results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication *** the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs.

关键词： Tea plant Hybrid origin Genetic diversity Domestication history Camellia sinensis var.assamica Camellia taliensis

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A thermodynamic perspective on electrode poisoning in solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1449-1455页

作者： kevin Huang Department of Mechanical Engineering University of South CarolinaColumbiaUSA

A critical challenge to the commercialization of clean and high-efficiency solid oxide fuel cell(sOFC)technology is the insuf-ficient stack lifespan caused by a variety of degradation mechanisms,which are associated with cell components and chemical *** components related degradation refers to thermal/chemical/electrochemical deterioration of cell materials under operating conditions,whereas the latter regards impurities in feedstocks of oxidant(air)and reductant(fuel).This article provides a thermodynamic perspective on the understanding of the impurities-induced degradation mechanisms in *** discussion focuses on using thermodynamic ana-lysis to elucidate poisoning mechanisms in cathodes by impurity species such as Cr,CO_(2),H_(2)O,and sO_(2) and in the anode by species such as s(or H_(2)s),siO_(2),and P_(2)(or PH_(3)).The author hopes the presented fundamental insights can provide a theoretical foundation for search-ing for better technical solutions to address the critical degradation challenges.

关键词： impurities air fuel reaction activity

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Model Change Active Learning in Graph-Based semi-supervised Learning

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1270-1298页

作者： kevin s.Miller Andrea L.Bertozzi Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLos AngelesCA 90095USA

Active learning in semi-supervised classification involves introducing additional labels for unlabelled data to improve the accuracy of the underlying classifier.A challenge is to identify which points to label to best improve performance while limiting the number of new labels."Model Change"active learning quantifies the resulting change incurred in the classifier by introducing the additional label(s).We pair this idea with graph-based semi-supervised learning(ssL)methods,that use the spectrum of the graph Laplacian matrix,which can be truncated to avoid prohibitively large computational and storage *** consider a family of convex loss functions for which the acquisition function can be efficiently approximated using the Laplace approximation of the posterior *** show a variety of multiclass examples that illustrate improved performance over prior state-of-art.

关键词： Active learning Graph-based methods semi-supervised learning(ssL) Graph Laplacian

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Rational Design and Construction of a Cds QDs/InVO4 Atomic-Layer（110）/（110） Facet s-scheme Heterojunction for Highly Efficient Photocatalytic Degradation of C2H4

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Energy & Environmental Materials 2024年第3期7卷 215-222页

作者： Yuanpeng Dong Peizhu Ji Xinyue Xu Rong Li Yin Wang kevin Peter Homewood Xiaohong Xia Yun Gao Xuxing Chen Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials School of Materials Science&Engineering Hubei University Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and Science state Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences United Water (Xianning) Company Limited

Exploring high efficiency s-scheme heterojunction photocatalysts with strong redox ability for removing volatile organic compounds from the air is of great interest and ***,how to predict and regulate the transport of photogenerated carriers in heterojunctions is a great ***,density functional theory calculations were first used to successfully predict the formation of a Cds quantum dots/InVO4atomic-layer （110）/（110） facet s-scheme ***,a Cds quantum dots/InVO4atomic-layer was synthesized by in-situ loading of Cds quantum dots with （110） facets onto the（110） facets of *** a result of the deliberately constructed built-in electric field between the adjoining facets,we obtain a remarkably enhanced photocatalytic degradation rate for *** rate is 13.8 times that of pure Cds and 13.2 times that of pure ***-situ irradiated X-ray photoelectron spectroscopy,photoluminescence and time-resolved photoluminescence measurements were carried *** experiments validate that the built-in electric field enhanced the dissociation of photoexcited excitons and the separation of free charge carriers,and results in the formation of s-scheme charge transfer *** reaction mechanism of the photocatalytic C2H4oxidation is investigated by in-situ electron paramagnetic *** work provides a mechanistic insight into the construction and optimization of semiconductor heterojunction photocatalysts for application to environmental remediation.

关键词： Cds QDs InVO4 atomic-layer photocatalysis s-scheme volatile organic compounds

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Post-fontan circulation hepatocellular carcinoma:Open and laparoscopic hepatectomy

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 90-93页

作者： Karin KY Ho Wong Hoi she simon HY Tsang kevin s Lo Tan To Cheung Department of surgery The University of Hong Kong102 Pok Fu Lam RoadHong KongChina Department of Anaesthesiology Queen Mary Hospital102 Pok Fu Lam RoadHong KongChina

To the Editor:Fontan-associated liver disease shows increasing incidence as advances in pediatric cardiology have prolonged life expectancy in patients with single ventricle congenital heart defects[1].Their unique physiology and procedure-related sequelae present an increasingly relevant challenge in hepatic *** hereby reported a series of patients suffering from hepatocellular carcinoma(HCC)who successfully underwent open and laparoscopic hepatectomy.

关键词： hepatocellular hepatectomy surgery

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Weight regain after intragastric balloon for pre-surgical weight loss

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World Journal of Gastrointestinal surgery 2024年第7期16卷 2040-2046页

作者： Danielle Abbitt kevin Choy Alexandra Kovar Teresa s Jones Krzysztof J Wikiel Edward L Jones Department of surgery University of ColoradoAuroraCO 80045United States Department of surgery Rocky Mountain Regional Veteran Affairs Medical CenterAuroraCO 80045United States

BACKGROUND Over one-third of Americans carry the diagnosis of obesity,many also with obesity-related *** can place patients at increased risk of operative and postoperative *** intragastric balloon has been shown to aid in minor weight loss,however its weight recidivism in patients requiring short interval weight loss has not been well *** To evaluate weight loss,ability to undergo successful elective surgery after intragastric balloon placement,and weight management after balloon *** This study is a retrospective review of patients in a single academic institution undergoing intragastric balloon placement from 2019-2023 to aid in weight loss prior to undergoing elective *** outcomes including weight loss,duration of balloon placement,successful elective surgery,weight regain postballoon and post-procedure complications were *** criteria included those with balloon in place at time of *** Thirty-three patients completed intragastric balloon therapy from 2019-2023 as a bridge to elective *** patients were required to participate in a 12-month weight management program to be eligible for balloon *** surgeries included incisional hernia repair,umbilical hernia repair,inguinal hernia repair,and knee and hip *** average age at placement was 53 years±11 years,majority(91%)were *** average duration of intragastric balloon therapy was 186 days±41 *** average weight loss was 14.0 kg±7.4 kg and with an average percent excess body weight loss of 30.0%(7.9%-73.6%).Over half of the patients(52.0%)achieved the goal of 30-50 lbs(14-22 kg)weight ***-one patients(64%)underwent their intended elective surgery,2 patients(6%)deferred surgery due to symptom relief with weight loss ***-one of the patients(64%)have documented weights in 3 months after balloon removal,in these patients the majority(76%)gained weight after balloon *** pat

关键词： Intragastric balloon Weight loss Obesity Bariatric Body mass index

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Dynamics of Advantageous Mutant spread in spatial Death-Birth and Birth-Death Moran Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 576-604页

作者： Jasmine Foo Einar Bjarki Gunnarsson kevin Leder David sivakoff school of Mathematics University of MinnesotaTwin CitiesMN55455USA Department of Industrial and systems Engineering University of MinnesotaTwin CitiesMN55455USA Departments of statistics and Mathematics The Ohio State UniversityColumbusOH43210USA

The spread of an advantageous mutation through a population is of fundamental interest in population genetics. While the classical Moran model is formulated for a well-mixed population, it has long been recognized that in real-world applications, the population usually has an explicit spatial structure which can significantly influence the dynamics. In the context of cancer initiation in epithelial tissue, several recent works have analyzed the dynamics of advantageous mutant spread on integer lattices, using the biased voter model from particle systems theory. In this spatial version of the Moran model, individuals first reproduce according to their fitness and then replace a neighboring individual. From a biological standpoint, the opposite dynamics, where individuals first die and are then replaced by a neighboring individual according to its fitness, are equally relevant. Here, we investigate this death-birth analogue of the biased voter model. We construct the process mathematically, derive the associated dual process, establish bounds on the survival probability of a single mutant, and prove that the process has an asymptotic shape. We also briefly discuss alternative birth-death and death-birth dynamics, depending on how the mutant fitness advantage affects the dynamics. We show that birth-death and death-birth formulations of the biased voter model are equivalent when fitness affects the former event of each update of the model, whereas the birth-death model is fundamentally different from the death-birth model when fitness affects the latter event.

关键词： spatial death-birth models spatial birth-death models spatial evolutionary models spatial cancer models Evolutionary graph theory stochastic processes Biased voter model Dual process Fixation probability shape theorem

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Infant’s sigh Breathing Matters—The Role of the Hering-Breuer Deflation Reflex in Bronchial Decongestion

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Open Journal of Therapy and Rehabilitation 2024年第3期12卷 197-212页

作者： Karine Truflandier kevin Albert Jean-Jacques Moraine Department of Cardio-Pulmonary Physiotherapy Hpital de La Tour Meyrin Switzerland Paediatric Intensive Care Unit Centre Hospitalier Universitaire Sainte-Justine Montral Canada Laboratoire des sciences de la Motricit Universit Libre de Bruxelles Brussel Belgium

Background: The prolonged slow expiratory (PsE) technique can induce sigh breaths related to the Hering-Breuer reflex in *** is a specific chest physiotherapy technique often used in children to help with the clearance of secretions, reduce pulmonary obstruction and decrease ventilatory effort. Purpose: The main objective of this review was to synthesize and clarify the existing knowledge of the physiological mechanism behind the Hering-Breuer reflex and its utility in the PsE technique. The secondary objective was to provide an overview of PsE which is probably the main mechanical feature for mucus clearance in infants and to identify gaps and any further research required. Method: A comprehensive literature search was performed using PubMed/MEDLINE and Ovid EMBAsE, from 1968 to January 2024, using search terms relating to “Interaction of Hering-Breuer reflex and chest physiotherapy therapy, sigh breath in infants and prolonged slow expiration technique” to create an overview of the advances and gaps in current knowledge of PsE. Result: The data obtained following treatment with PsE maneuvers in infants with histories of recurrent wheezing shows that the presence of sighs could be the main active principle of treatment. Conclusion: Changes in volume induced by PsE technique and, effects from crying may stimulate the Hering-Breuer deflation reflex and sighs in turn improving alveolar ventilation as well as lung volume in infants.

关键词： Hering-Breuer (HB) Reflex sigh Breath Infants Prolonged slow Expiration Technique Large Volume Chest Physiotherapy

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Multinuclear MR and MRI study of lithium-ion cells using a variable field magnet and a fixed frequency RF probe

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Magnetic Resonance Letters 2024年第1期4卷 10-20页

作者： Andrés Ramírez Aguilera Florin Marica kevin J.sanders Md Al Raihan C.Adam Dyker Gillian R.Goward Bruce *** UNB MRI Centre Department of PhysicsUniversity of New BrunswickFrederictonNew BrunswickE3B 5A3Canada Department of Chemistry McMaster UniversityHamiltonOntarioL8S 4L8Canada Department of Chemistry University of New BrunswickFrederictonNew BrunswickE3B 5A3Canada

An exploratory multinuclear magnetic resonance(MR)and magnetic resonance imaging(MRI)study was performed on lithium-ion battery cells with ^(7)Li,^(19)F,and ^(1)H measurements.A variable field superconducting magnet with a fixed frequency parallel-plate radiofrequency(RF)probe was employed in the *** magnetic field was changed to set the resonance frequency of each nucleus to the fixed RF probe frequency of 33.7 *** cartridge-like lithium-ion cells,with graphite anodes and LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2)(NMC)cathodes,were *** cell was pristine,and one was charged to a cell voltage of 4.2 *** results presented demonstrate the great potential of the variable field magnet approach in multinuclear measurement of lithium-ion *** methods open the door for developing faster and simpler methods for detecting,quantifying,and interpreting MR and MRI data from lithium-ion and other batteries.

关键词： Multinuclear MR/MRI Variable field magnet Lithium-ion battery Parallel-plate rf probe

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