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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

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

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

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

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

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

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

Pharmacological methods for ovarian function and fertility preservation in women with cancer:A literature review

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Oncology Research 2024年第8期32卷 1309-1322页

作者： ANA s.CVETANOVIC MATTEO LAMBERTINI kevin PUNIE GORANA G.MATOVINA BRKO NIKOLA D.ZIVKOVIC MAJA J.POPOVIC MARIJANA M.MILOVIC KOVACEVIC LAZAR s.POPOVIC Department for Oncology Medical Faculty NisUniversity of NisNis18000Serbia Clinic of Oncology University Clinical Centre NisNis18000Serbia Department of Internal Medicine and Medical sciences(DiMI) School of MedicineUniversity of GenovaGenova16100Italy Department of Medical Oncology U.O.C Clinica di Oncologia MedicaIRCCS Ospedale Policlinico San MartinoGenova16100Italy Department of General Medical Oncology and Multidisciplinary Breast Centre Leuven Cancer InstituteUniversity Hospitals LeuvenLeuven3001Belgium Department of Medical Oncology Oncology Institute of VojvodinaSremska Kamenica21208Serbia Department for Pathology Medical Faculty NisUniversity of NisNis18000Serbia Center for Pathology University Clinical Centre NisNis18000Serbia Faculty of Medicine University of Novi SadNovi Sad21000Serbia Department of Medical Oncology Institute of Oncology and Radiology SerbiaBelgrade11000Serbia

Oncofertility is an extremely signiﬁcant topic that is increasingly being discussed owing to increased evidence indicating that fertility preservation does not affect the treatment outcomes of patients with cancer but signiﬁcantly contributes to preserving life *** effect of chemotherapy can range from minimal effects to complete ovarian *** data are available on the effects of monoclonal antibodies and targeted therapies on the ovaries and *** ovarian suppression by administering a gonadotropin-releasing hormone agonist(GnRHa)during chemotherapy decreases the gonadotoxic effect of chemotherapy,thereby diminishing the chance of developing premature ovarian insufﬁciency(POI).At present,the concomitant administration of GnRH analogs during chemotherapy is the only accepted pharmacological method for preserving ovarian ***,most randomized studies on the effectiveness of luteinizing hormone-releasing hormone agonists during chemotherapy in preventing POI have been conducted in women with breast cancer,with a considerably small number of studies on patients with hematological ***,most randomized controlled trials on breast cancer have revealed a decrease in treatment-induced POI risk,regardless of the hormone receptor *** addition,studies on hematological malignancies have yielded negative results;nevertheless,theﬁndings must be interpreted with caution owing to numerous *** guidelines from the American society of Clinical Oncology and EsMO Clinical Practice Guidelines recommend sperm,oocyte,and embryo cryopreservation as a standard practice and only offering GnRHa to patients when proven fertility preservation methods are not *** this manuscript,we present a comprehensive literature overview on the application of ovarian suppression with GnRHa during chemotherapy in patients with cancer by addressing preclinical and clinical data,as well as future perspectives in thisﬁeld

关键词： Gonadotropin-releasing hormone agonists(GnRHa) Fertility preservation Premature ovarian insufficiency(POI) Premenopausal patients

Potential transformation of organic matter by microbes in cryoconite,Tibetan Plateau

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science China Earth sciences 2024年第6期67卷 1978-1989页

作者： Bixi GUO Yongqin LIU kevin Xu ZHONG Quan sHI Chen HE Qiang ZHENG Ruanhong CAI state Key Laboratory of Tibetan Plateau Earth system Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for the Pan-Third Pole Environment Lanzhou UniversityLanzhou 730000China Department of Earth Oceanand Atmospheric SciencesUniversity of British ColumbiaVancouverBC V6T 1Z4Canada state Key Laboratory of Heavy Oil Processing Petroleum Molecules Engineering Center(PMEC)China University of PetroleumBeijing 102249China state Key Laboratory for Marine Environmental science Collage of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Fujian Key Laboratory of Marine Carbon sequestration Xiamen UniversityXiamen 361005China

Microorganisms play an essential role in the glacier carbon cycle;how they transform organic matter in mountain glacial cryoconite remains to be ***,we applied ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR Ms)and deep sequencing of 16s rRNA gene,to investigate the temporal microbial transformation of dissolved organic matter(DOM)of the Tibetan Plateau *** the 60-day incubation,we found that DOM in cryoconite underwent a three-stage transformation,with decreasing bioavailability over *** microbial community did not change much in the first week while degrading DOM molecules that were associated with higher H/C_(wa)and lower O/C_(wa).During days 15-30,DOM composition remained stable while microbial diversity *** day 60,the DOM was microbially converted into a higher state of recalcitrance,with higher values of aromatic index,O/C_(wa),and lower H/C_(wa),which contained molecules containing more *** among various microbial taxa,like Cyanobacteria,Bacteroidota,Gammaproteobacteria,Firmicutes,and Actinobacteriota,drove the DOM transformation in *** study sheds light on the in-situ transformation of DOM composition meditated by microbial populations in cryoconite at a temporal scale,providing new insights into understanding the microbial roles in the glacier organic carbon transformation.

关键词： Cryoconite Dissolved organic matter Biodegradation Microbial community Temporal variation