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CO_(2)enrichment accelerates successional development of an understory plant community

journal of Plant Ecology 2010年第1期3卷 33-39页

作者： Lara Souza R.Travis Belote Paul Kardol jake F.Weltzin richard j.norby Environmental Sciences Division Oak Ridge National LaboratoryBuilding 1062PO Box 2008Oak RidgeTN 37831USA Department of Ecology and Evolutionary Biology 569 Dabney HallUniversity of TennesseeKnoxvilleTN 37996USA The Wilderness Society 503 West Mendenhall St BozemanMT 59715USA USA National Phenology Network National Coordinating officeTucsonAZ 85721USA

Aims Rising concentrations of atmospheric carbon dioxide([CO_(2)])may influence forest successional development and species composition of understory plant communities by altering biomass production of plant species of functional groups.Here,we describe how elevated[CO_(2)](eCO_(2))affects aboveground biomass within the understory community of a temperate deciduous forest at the Oak Ridge National Laboratory sweetgum(Liquidambar styraciflua)free-air carbon dioxide enrichment(FACE)facility in eastern Tennessee,USA.We asked if(i)CO_(2)enrichment affected total understory biomass and(ii)whether total biomass responses could be explained by changes in understory species composition or changes in relative abundance of functional groups through time.Materials and methods The FACE experiment started in 1998 with three rings receiving ambient[CO_(2)](aCO_(2))and two rings receiving eCO_(2).From 2001 to 2003,we estimated species-specific,woody versus herbaceous and total aboveground biomass by harvesting four 130.5-m subplots within the established understory plant community in each FACE plot.In 2008,we estimated herbaceous biomass as previously but used allometric relationships to estimate woody biomass across two 535-m quadrats in each FACE plot.Important findings Across years,aboveground biomass of the understory community was on average 25%greater in eCO_(2)than in aCO_(2)plots.We could not detect differences in plant species composition between aCO_(2)and eCO_(2)treatments.However,we did observe shifts in the relative abundance of plant functional groups,which reflect important structural changes in the understory community.In 2001-03,little of the understory biomass was in woody species;herbaceous species made up 94%of the total understory biomass across[CO_(2)]treatments.Through time,woody species increased in importance,mostly in eCO_(2),and in 2008,the contribution of herbaceous species to total understory biomass was 61%in aCO_(2)and only 33%in eCO_(2)treatments.Our results suggest that rising atmospheric[CO_(2)

关键词： community composition FACE aboveground biomass woody herbaceous sweetgum Microstegium vimineum Lonicera japonica

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Responses of an old-field plant community to interacting factors of elevated[CO_(2)],warming,and soil moisture

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journal of Plant Ecology 2009年第1期2卷 1-11页

作者： E.Cayenne Engel jake F.Weltzin richard j.norby Aimee T.Classen Department of Ecology and Evolutionary Biology University of Tennessee569 Dabney HallKnoxvilleTN 37996-1610USA Environmental Sciences Division Oak Ridge National LaboratoryOne Bethel Valley RoadBuilding 1062Oak RidgeTN 37831-6422USA Present address:USA National Phenology Network National Coordinating Office1955 East 6th StreetTucsonAZ 85721USA

Aims The direct effects of atmospheric and climatic change factors—atmospheric[CO_(2)],air temperature and changes in precipitation—can shape plant community composition and alter ecosystem function.It is essential to understand how these factors interact to make better predictions about how ecosystems may respond to change.We investigated the direct and interactive effects of[CO_(2)],warming and altered soil moisture in open-top chambers(OTCs)enclosing a constructed old-field community to test how these factors shape plant communities.Materials and methods The experimental facility in Oak Ridge,TN,USA,made use of 4-m diameter OTCs and rain shelters to manipulate[CO_(2)](ambient,ambient+300 ppm),air temperature(ambient,ambient+3.5C)and soil moisture(wet,dry).The plant communities within the chambers comprised seven common old-field species,including grasses,forbs and legumes.We tracked foliar cover for each species and calculated community richness,evenness and diversity from 2003 to 2005.Important findings This work resulted in three main findings:(1)warming had speciesspecific effects on foliar cover that varied through time and were altered by soil moisture treatments;(2)[CO_(2)]had little effect on individual species or the community;(3)diversity,evenness and richness were influenced most by soil moisture,primarily reflecting the response of one dominant species.We conclude that individualistic species responses to atmospheric and climatic change can alter community composition and that plant populations and communities should be considered as part of analyses of terrestrial ecosystem response to climate change.However,prediction of plant community responses may be difficult given interactions between factors and changes in response through time.

关键词： climate change foliar cover multi-factor interactions diversity richness

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RecBERT:Semantic recommendation engine with large language model enhanced query segmentation for k-nearest neighbors ranking retrieval

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Intelligent and Converged Networks 2024年第1期5卷 42-52页

作者： richard Wu the Dublin Unified School District and the SF Artificial Intelligence Club DublinCA 94568USA

The increasing amount of user traffic on Internet discussion forums has led to a huge amount of unstructured natural language data in the form of user comments.Most modern recommendation systems rely on manual tagging,relying on administrators to label the features of a class,or story,which a user comment corresponds to.Another common approach is to use pre-trained word embeddings to compare class descriptions for textual similarity,then use a distance metric such as cosine similarity or Euclidean distance to find top k neighbors.However,neither approach is able to fully utilize this user-generated unstructured natural language data,reducing the scope of these recommendation systems.This paper studies the application of domain adaptation on a transformer for the set of user comments to be indexed,and the use of simple contrastive learning for the sentence transformer fine-tuning process to generate meaningful semantic embeddings for the various user comments that apply to each class.In order to match a query containing content from multiple user comments belonging to the same class,the construction of a subquery channel for computing class-level similarity is proposed.This channel uses query segmentation of the aggregate query into subqueries,performing k-nearest neighbors(KNN)search on each individual subquery.RecBERT achieves state-of-the-art performance,outperforming other state-of-the-art models in accuracy,precision,recall,and F1 score for classifying comments between four and eight classes,respectively.RecBERT outperforms the most precise state-of-the-art model(distilRoBERTa)in precision by 6.97%for matching comments between eight classes.

关键词： sentence transformer simple contrastive learning large language models query segmentation k-nearest neighbors

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Comparative utility of vestibular function tests in patients with peripheral and central vestibular dysfunction

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journal of Otology 2024年第1期19卷 5-9页

作者： Cameron B.Fattahi Christopher Zaro janice j.Chung richard F.Lewis Divya A.Chari Department of Otolaryngology-Head and Neck Surgery UMASS Memorial Medical CenterUniversity of Massachusetts Chan Medical SchoolWorcesterMAUSA jenks Vestibular Physiology Laboratory Massachusetts Eye and EarBostonMAUSA Department of Otolaryngology-Head and Neck Surgery Massachusetts Eye and EarHarvard Medical SchoolBostonMAUSA Department of Neurology Harvard Medical SchoolBostonMAUSA

Background: Bithermal caloric irrigation, video head impulse test(vHIT), and rotational testing are commonly used to assess peripheral vestibular function, but the relative clinical utility of each test in differentiating patients with peripheral vestibulopathy is debated.Objectives: To determine whether(1) the combination of two or more vestibular tests enhances diagnostic utility over a single test;(2) abnormal test results on vestibular tests correlate with one another.Methods: Retrospective analysis of data collected from multidisciplinary vestibular clinics at two academic medical centers from 2016 to 2022.Results: 150 patients(54.10 ± 15.09 years, 88 females) were included. No individual test was significantly better at predicting the presence of peripheral vestibular damage(p > 0.05). vHIT test results improved significantly when combined with either the caloric test(p = 0.007) or rotary chair test(p = 0.039). Caloric and rotational testing had high sensitivity(74.65% and 76.06%, respectively) and specificity(83.54% and 78.48%, respectively). vHIT demonstrated excellent specificity(89.87%) but poor sensitivity(47.89%). Caloric, vHIT, and rotary chair tests results did not correlate with one another(p > 0.05).Conclusions: Vestibular function tests have comparable diagnostic utility, yet each offers unique advantages. Caloric and rotational testing may be best suited for screening peripheral damage and vHIT may function ideally as a confirmatory test.

关键词： vestibular patients specificity

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Liver transplantation as an alternative for the treatment of non-resectable liver colorectal cancer: Advancing the therapeutic algorithm

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 154-159页

作者： Badi Rawashdeh richard Bell Abdul Hakeem Raj Prasad Division of Transplant Surgery Department of General SurgeryMedical College of WisconsinMilwaukeeWI53226USA Leeds Teaching Hospital LeedsUK

Colorectal cancer is a leading cause of cancerrelated mortality,with nearly half of the affected patients developing liver metastases.For three decades,liver resection(LR)has been the primary curative strategy,yet its applicability is limited to about 20%of cases.Liver transplantation(LT)for unresectable metastases was attempted unsuccessfully in the 1990s,with high rates of perioperative death and recurrence.There is now more interest in this strategy due to improvements in systemic therapies and surgical techniques.A significant study conducted by the Oslo group showed that patients receiving liver transplants had a 60%chance of survival after five years.Significantly better results have been achieved by using advanced imaging for risk stratification and further refining selection criteria,especially in the Norvegian SECA trials.This review carefully charts the development and history of LT as a treatment option for colorectal cancer liver metastases.The revolutionary path from the early days of exploratory surgery to the current situation of cautious optimism is traced,highlighting the critical clinical developments and improved patient selection standards that have made LT a potentially curative treatment for such challenging very well selected cases.

关键词： Liver transplantation Colorectal cancer liver metastases Non-resectable liver metastases

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Amino acid and mineral digestibility,bone ash,and plasma inositol is increased by including microbial phytase in diets for growing pigs

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journal of Animal Science and Biotechnology 2024年第2期15卷 699-712页

作者： Liz Vanessa Lagos Mike richard Bedford Hans Henrik Stein Division of Nutritional Sciences University of IllinoisUrbanaIL 61801USA AB Vista Marlborough SN84ANUK

Background The effect of microbial phytase on amino acid and energy digestibility is not consistent in pigs,which may be related to the phytase dosage or the adaptation length to the diet.Therefore,an experiment was conducted to test the hypotheses that increasing dietary phytase after an 18-day adaptation period:1)increases nutrient and energy digestibility;2)increases plasma P,plasma inositol,and bone ash of young pigs;and 3)demonstrates that maximum phytate degradation requires more phytase than maximum P digestibility.Results Data indicated that increasing inclusion of phytase[0,250,500,1,000,2,000,and 4,000 phytase units(FTU)/kg feed]in corn-soybean meal-based diets increased apparent ileal digestibility(AID)of Trp(quadratic;P<0.05),and of Lys and Thr(linear;P<0.05),and tended to increase AID of Met(linear;P<0.10).Increasing dietary phytase also increased AID and apparent total tract digestibility(ATTD)of Ca and P(quadratic;P<0.05)and increased ATTD of K and Na(linear;P<0.05),but phytase did not influence the ATTD of Mg or gross energy.Concentrations of plasma P and bone ash increased(quadratic;P<0.05),and plasma inositol also increased(linear;P<0.05)with increasing inclusion of phytase.Reduced concentrations of inositol phosphate(IP)6 and IP5(quadratic;P<0.05),reduced IP4 and IP3(linear;P<0.05),but increased inositol concentrations(linear;P<0.05)were observed in ileal digesta as dietary phytase increased.The ATTD of P was maximized if at least 1,200 FTU/kg were used,whereas more than 4,000 FTU/kg were needed to maximize inositol release.Conclusions Increasing dietary levels of phytase after an 18-day adaptation period increased phytate and IP ester degradation and inositol release in the small intestine.Consequently,increasing dietary phytase resulted in improved digestibility of Ca,P,K,Na,and the first 4 limiting amino acids,and in increased concentrations of bone ash and plasma P and inositol.In a corn-soybean meal diet,maximum inositol release requires approximately 3,200 FTU/kg more phytase than that re

关键词： Bone ash Inositol Nutrient digestibility Phytase Phytate degradation Pigs

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Determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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Pedosphere 2024年第3期34卷 530-539页

作者： Daniel D.SAURETTE Asim BISWAS richard j.HECK Adam W.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental covariates.Strategies to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM community.Despite advances in sampling design,a critical gap remains in determining the number of samples required for DSM projects.We propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin width.Data preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the histogram.Based on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample size.This technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of QRs.The results showed increasing minimum sample size with an increase in the QR selected.Minimum sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%QR.This technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

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Genetic pathways in cerebral palsy:a review of the implications for precision diagnosis and understanding disease mechanisms

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Neural Regeneration Research 2024年第7期19卷 1499-1508页

作者： Yiran Xu Yifei Li Seidu A.richard Yanyan Sun Changlian Zhu Henan Key Laboratory of Child Brain Injury and Henan Pediatric Clinical Research Center Institute of Neuroscience and The Third Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina National Health Council(NHC)Key Laboratory of Birth Defects Prevention Henan Key Laboratory of Population Defects PreventionZhengzhouHenan ProvinceChina Department of Human Anatomy School of Basic Medicine and Institute of NeuroscienceZhengzhou UniversityZhengzhouHenan ProvinceChina Center for Brain Repair and Rehabilitation Institute of Neuroscience and PhysiologyUniversity of GothenburgGothenburgSweden

Ce rebral palsy is a diagnostic term utilized to describe a group of permanent disorders affecting movement and posture.Patients with cerebral palsy are often only capable of limited activity,resulting from non-progressive disturbances in the fetal or neonatal brain.These disturbances severely impact the child’s daily life and impose a substantial economic burden on the family.Although cerebral palsy encompasses various brain injuries leading to similar clinical outcomes,the unde rstanding of its etiological pathways remains incomplete owing to its complexity and heterogeneity.This review aims to summarize the current knowledge on the genetic factors influencing cerebral palsy development.It is now widely acknowledged that genetic mutations and alterations play a pivotal role in cerebral palsy development,which can be further influenced by environmental fa ctors.Des pite continuous research endeavors,the underlying fa ctors contributing to cerebral palsy remain are still elusive.However,significant progress has been made in genetic research that has markedly enhanced our comprehension of the genetic factors underlying cerebral palsy development.Moreove r,these genetic factors have been categorized based on the identified gene mutations in patients through clinical genotyping,including thrombosis,angiogenesis,mitochondrial and oxidative phosphorylation function,neuronal migration,and cellular autophagy.Furthermore,exploring targeted genotypes holds potential for precision treatment.In conclusion,advancements in genetic research have substantially improved our understanding of the genetic causes underlying cerebral palsy.These breakthroughs have the potential to pave the way for new treatments and therapies,consequently shaping the future of cerebral palsy research and its clinical management.The investigation of cerebral palsy genetics holds the potential to significantly advance treatments and management strategies.By elucidating the underlying cellular mechanisms,we can develop to rgeted interventions to optimiz

关键词： cerebral palsy environmental factors etiology genetic factors genetic mutation movement disorder spastic diplegia

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New analytical modelling of fractional generalized Kuramoto-Sivashinky equation via Atangana-Baleanu operator and j-transform method

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journal of Ocean Engineering and Science 2024年第1期9卷 66-88页

作者： Metonou richard Weidong Zhao Shehu Maitama School of Mathematics Shandong UniversityJinanShandongChina

In this paper,we propose a new analytical modelling of the well-known fractional generalized Kuramoto-Sivashinky equation(FGKSE)using fractional operator with non-singular kernel and the homotopy anal-ysis transform method via j-transform method.Also,using fixed-point theorem,we prove the existence and uniqueness of our proposed solution to the fractional Kuramoto-Sivashinky equation.To further val-idate the efficiency of the suggested technique,we proved the convergence analysis of the method and provide the error estimate.The obtained solutions of the FGKSE,describing turbulence processes in the field of ocean engineering are analytically and numerically compared to show the behaviors of many parameters of the present model.

关键词： Homotopy analysis j-transform method j-transform method Fractional generalized Kuramoto-Sivashinky equation Fixed-point theorem Numeric-symbolic computation

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Parameter-Free Shifted Laplacian Reconstruction for Multiple Kernel Clustering

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IEEE/CAA journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： Xi Wu Zhenwen Ren F.richard Yu the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010China the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian reconstruction.Traditional MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian.

关键词： parameter letter Parameter

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