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Jacobi Structures on Affine Bundles

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Acta Mathematica Sinica,English Series 2007年第5期23卷 769-788页

作者： J.GRABOWSKI d.IGLESIAS J.C.MARRERO E.PAdRN P.URBA■SKI Mathematical InstitutePolish Academy of Sciences Sniadeckich 8P.O.Box 2100-956 WarsawPoland Instituto de Matemáticas y Física FundamentalConsejo Superior de Investigaciones CientificasSerrano 12328006 MadridSpain departamentode Matemática FundamentalFacultad de MatemáticasUniversidad de la LagunaLa LagunaTenerifeCanary IslandsSpain division of Mathematical Methods in PhysicsUniversity of Warsaw Hoia 7400-682 WarsawPoland

Abstract We study affine Jacobi structures （brackets） on an affine bundle π ： A → M, i.e. Jacobi brackets that close on affine functions. We prove that if the rank of A is non-zero, there is a one-toone correspondence between affine Jacobi structures on A and Lie algebroid structures on the vector bundle A^＋ = ∪p∈M Aff（Ap, R） of affine functionals. In the case rank A = 0, it is shown that there is a one-to-one correspondence between affine Jacobi structures on A and local Lie algebras on A^＋. Some examples and applications, also for the linear case, are discussed. For a special type of affine Jacobi structures which are canonically exhibited （strongly-affine or affine-homogeneous Jacobi structures） over a real vector space of finite dimension, we describe the leaves of its characteristic foliation as the orbits of an affine representation. These affine Jacobi structures can be viewed as an analog of the Kostant-Arnold-Liouville linear Poisson structure on the dual space of a real finite-dimensional Lie algebra.

关键词： Vector and affine bundles Jacobi manifolds Lie algebroids

Biparental behavior in the burying beetle Nicrophorus orbicollis： a role for dopamine？

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Current Zoology 2016年第3期62卷 285-291页

作者： S. Carmen PANAITOF Jazmine d. W. YAEGER Jarod P. SPEER Kenneth J. RENNER department of Biology UniversiW of Nebraska at Keamey Kearney NE 68849 USA department of Biology University of South Dakota Vermillion SD 57069 USA

Burying beetles Nicrophorus orbicollis exhibit facultative biparental care of young. To reproduce, a male-female burying beetle pair bury and prepare a small vertebrate carcass as food for its altricial young. during a breeding bout, male and female behavior changes synchronously at appropriate times and is coordinated to provide effective care for offspring. Although the ecologicaJ and evolutionary factors that shape this remarkable reproductive plasticity are well characterized, the neuromodulation of parental behavior is poorly understood. Juvenile hormone levels rise dramat- ically at the time beetle parents accept and feed larvae, remain highly elevated during the stages of most active care and fall abruptly when care is terminated. However, hormonal fluctuations alone cannot account for this elaborate control of reproduction. The biogenic amines octopamine （OA）, dopamine （dA）, and serotonin （5-HT） mediate a diversity of insect reproductive and social behav- iors. In this study, we measured whole brain monoamine levels in individual male and female bury- ing beetles and compared OA, dA, and 5-HT profiles between breeding （parental） and nonbreed- ing, unmated beetles. Remarkably, after 24 h of care, when parental feeding rates begin to peak, dA brain levels increase in breeding beetles when compared to nonbreeding controls. In contrast, brain OA and 5-HT levels did not change significantly. These results provide the first evidence for a potential role of dA in the modulation of burying beetle parental behavior.

关键词： dopamine Nicrophorus neuromodulation octopamine parental care serotonin.

Machine-learning based landslide susceptibility modelling with emphasis on uncertainty analysis

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Geoscience Frontiers 2023年第6期14卷 327-340页

作者： A.L.Achu C.d.Aju Mariano di Napoli Pranav Prakash Girish Gopinath E.Shaji Vinod Chandra department of Climate Variability and Aquatic Ecosystems Kerala University of Fisheries and Ocean Studies(KUFOS)KochiKerala 682508India department of Geology University of KeralaThiruvananthapuramKerala 695581India department of Earth Environment and Life SciencesUniversity of GenoaCorso Europa26Genoa 16132Italy department of Computer Science University of KeralaThiruvananthapuramKerala 695581India

Landslide susceptibility maps are vital tools used by decision-makers to adopt mitigation strategies for future *** this context,research on landslide susceptibility modelling has become a topic of relevance and is in constant *** various machine-learning techniques(MLTs)have been identified for landslide susceptibility modelling,the uncertainty inherent in the models is rarely *** present study attempts to quantify the uncertainty associated with landslide prediction models by developing a new methodological framework based on the ensembles of the eight *** methodology has been tested at the highlands of the southern Western Ghats region(Kerala,India),where landslides have frequently been *** landslide conditioning factors have been identified as part of this study,and their association was correlated with 671 historic landslides in the study *** study used four ensemble models such as the mean of probabilities,the median of probabilities,the weighted mean of probabilities,and the committee *** weighted mean of probability was proved to be the best model based on the average of 800 standalone MLTs,viz.,receiver operating characteristics,true skill statistics,and area under curve with corresponding validation ***,an uncertainty analysis was carried out on the coefficient of variation.A confident map was generated to represent the distinct zonation of landslide susceptibility areas with definite uncertainty *** 74%of the past landslides fall in the higher susceptibility-low uncertainty *** is also inferred that such micro-level zonation based on MLTs may improve the efficiency of landslide susceptibility maps and may help in accurately identifying landslide-prone areas in the *** confident maps thus generated can be used as a ready reference to the planners for the formulation of landslide adaptation strategies at micro-scales.

关键词： Landslides Machine-learning Ensemble model Kerala India

Metformin may be a viable adjunctive therapeutic option to potentially enhance immune reconstitution in HIV-positive immunological non-responders

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Chinese Medical Journal 2023年第18期136卷 2147-2155页

作者： Silvere d.Zaongo Yaokai Chen division of Infectious diseases Chongqing Public Health Medical CenterChongqing 400036China.

Incomplete immune reconstitution remains a global challenge for human immunodeficiency virus(HIV)treatment in the present era of potent antiretroviral therapy(ART),especially for those individuals referred to as immunological non-responders(INRs),who exhibit dramatically low Cd4^(+)T-cell counts despite the use of effective antiretroviral therapy,with long-term inhibition of viral *** this review,we provide a critical overview of the concept of ART-treated HIV-positive immunological non-response,and also explain the known mechanisms which could potentially account for the emergence of immunological non-response in some HIV-infected individuals treated with appropriate and effective *** found that immune cell exhaustion,combined with chronic inflammation and the HIV-associated dysbiosis syndrome,may represent strategic aspects of the immune response that may be fundamental to incomplete immune ***,we noted from the literature that metformin exhibits properties and characteristics that may potentially be useful to specifically target immune cell exhaustion,chronic inflammation,and HIV-associated gut dysbiosis syndrome,mechanisms which are now recognized for their critically important complicity in HIV disease-related incomplete immune *** light of evidence discussed in this review,it can be seen that metformin may be of particularly favorable use if utilized as adjunctive treatment in INRs to potentially enhance immune *** approach described herein may represent a promising area of therapeutic intervention,aiding in significantly reducing the risk of HIV disease progression and mortality in a particularly vulnerable subgroup of HIV-positive individuals.

关键词： HIV Human immunodeficiency virus Immune reconstitution Immunological non-responders Metformin

Large-diameter trees, snags, and deadwood in southern Utah, USA

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Ecological Processes 2021年第1期10卷 130-141页

作者： James A.Lutz Soren Struckman Tucker J.Furniss Joseph d.Birch Larissa *** darren J.McAvoy department of Wildland Resources S.J.and Jessie E.Quinney College of Natural ResourcesUtah State University5230 Old Main HillLoganUT 84322-5230USA. department of Renewable Resources University of AlbertaEdmontonAlbertaCanada.

Background:The epidemic dendroctonus rufipennis(spruce beetle)outbreak in the subalpine forests of the Colorado Plateau in the 1990s killed most larger Picea engelmannii(Engelmann spruce)*** quarter century later,the larger snags are beginning to fall,transitioning to deadwood(down woody debris)where they may influence fire behavior,regeneration,and habitat ***:We tracked all fallen trees≥1 cm in diameter at breast height(1.37-m high)and mapped all pieces of deadwood≥10-cm diameter and≥1 m in length within 13.64 ha of a high-elevation mixed-species forest in the Picea–Abies zone annually for 5 years from 2015 through *** examined the relative contribution of Picea engelmannii to snag and deadwood pools relative to other species and the relative contributions of large-diameter trees(≥33.2 cm at this subalpine site).We compared spatially explicit mapping of deadwood to traditional measures of surface fuels and introduce a new method for approximating vertical distribution of ***:In this mixed-species forest,there was relatively high density and basal area of live Picea engelmannii 20 years after the beetle outbreak(36 trees ha^(−1) and 1.94 m^(2) ha^(−1)≥10-cm diameter)contrasting with the near total mortality of mature Picea in forests *** from tree boles≥10-cm diameter on the ground had biomass of 42 Mg ha^(−1),7 Mg ha^(−1) of Picea engelmannii,and 35 Mg ha^(−1) of other *** live aboveground biomass was 119 Mg ha^(−1),while snag biomass was 36 Mg ha^(−1).Mean total fuel loading measured with planar transects was 63 Mg ha^(−1) but varied more than three orders of magnitude(0.1 to 257 Mg ha^(−1)).Planar transects recorded 32 Mg ha^(−1) of wood≥7.62-cm diameter compared to the 42 Mg ha^(−1) of wood≥10-cm diameter recorded by explicit *** pieces of deadwood were often stacked,forming a vertical structure likely to contribute to active fire ***:Bark beetle mortality in the 1990s has made

关键词： Cedar Breaks National Monument dendroctonus rufipennis Utah Forest dynamics Plot Vertical fuel structure

Identification of predictive MRI and functional biomarkers in a pediatric piglet traumatic brain injury model

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Neural Regeneration Research 2021年第2期16卷 338-344页

作者： Hongzhi Wang Emily W.Baker Abhyuday Mandal Ramana M.Pidaparti Franklin d.West Holly A.Kinder department of Statistics University of GeorgiaAthensGAUSA Regenerative Bioscience Center University of GeorgiaAthensGAUSA department of Animal and dairy Science University of GeorgiaAthensGAUSA College of Engineering University of GeorgiaAthensGAUSA

Traumatic brain injury(TBI) at a young age can lead to the development of long-term functional impairments. Severity of injury is well demonstrated to have a strong influence on the extent of functional impairments;however, identification of specific magnetic resonance imaging(MRI) biomarkers that are most reflective of injury severity and functional prognosis remain elusive. Therefore, the objective of this study was to utilize advanced statistical approaches to identify clinically relevant MRI biomarkers and predict functional outcomes using MRI metrics in a translational large animal piglet TBI model. TBI was induced via controlled cortical impact and multiparametric MRI was performed at 24 hours and 12 weeks post-TBI using T1-weighted, T2-weighted, T2-weighted fluid attenuated inversion recovery, diffusion-weighted imaging, and diffusion tensor imaging. Changes in spatiotemporal gait parameters were also assessed using an automated gait mat at 24 hours and 12 weeks post-TBI. Principal component analysis was performed to determine the MRI metrics and spatiotemporal gait parameters that explain the largest sources of variation within the datasets. We found that linear combinations of lesion size and midline shift acquired using T2-weighted imaging explained most of the variability of the data at both 24 hours and 12 weeks post-TBI. In addition, linear combinations of velocity, cadence, and stride length were found to explain most of the gait data variability at 24 hours and 12 weeks post-TBI. Linear regression analysis was performed to determine if MRI metrics are predictive of changes in gait. We found that both lesion size and midline shift are significantly correlated with decreases in stride and step length. These results from this study provide an important first step at identifying relevant MRI and functional biomarkers that are predictive of functional outcomes in a clinically relevant piglet TBI model. This study was approved by the University of Georgia I

关键词： controlled cortical impact gait analysis linear regression magnetic resonance imaging motor function pediatric pig model principal component analysis traumatic brain injury

Hemopneumothorax detection through the process of artificial evolution-a feasibility study

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Military Medical Research 2022年第1期9卷 12-20页

作者： Adir Sommer Noy MarkGavriel d.Kohlberg Rafi Gerasi Linn Wagnert Avraham Ruth Fan-Marko Arik Eisenkraft dean Nachman The Medical Corps Israel Defense Forces(IDF)Tel Hashomer5262000 Ramat GanIsrael department of Otolaryngology-Head and Neck Surgery University of WashingtonSeattleWA 98195USA The Institute for Research in Military Medicine the Faculty of Medicinethe Hebrew University of Jerusalem and the IDF Medical Corps9112102 JerusalemIsrael The Hebrew University School of Medicine 9112102 JerusalemIsrael department of Medicine Hadassah Medical Center9112102 JerusalemIsrael.

Background:Tension pneumothorax is one of the leading causes of preventable death on the *** prehospital diagnosis relies on a subjective clinical impression complemented by a manual thoracic and respiratory *** techniques are not fully applicable in field conditions and on the battlefield,where situational and environmental factors may impair clinical *** aimed to assemble a device able to sample,analyze,and classify the unique acoustic signatures of pneumothorax and ***:Acoustic data was obtained with simultaneous use of two sensitive digital stethoscopes from the chest wall of an ex-vivo porcine *** second samples of acoustic data were obtained from the in-house assembled digital stethoscope system during mechanical *** thoracic cavity was injected with increasing volumes of 200,400,600,800,and 1000 ml of air or saline to simulate pneumothorax and hemothorax,*** data was analyzed using a multi-objective genetic algorithm that was used to develop an optimal mathematical detector through the process of artificial evolution,a cutting-edge approach in the artificial intelligence ***:The in-house assembled dual digital stethoscope system and developed genetic algorithm achieved an accuracy,sensitivity and specificity ranging from 64%to 100%,63%to 100%,and 63%to 100%,respectively,in classifying acoustic signal as associated with pneumothorax or hemothorax at fluid injection levels of 400 ml or more,and regardless of background ***:We present a novel,objective device for rapid diagnosis of potentially lethal thoracic *** further optimization,such a device could provide real-time detection and monitoring of pneumothorax and hemothorax in battlefield conditions.

关键词： Pneumothorax Hemothorax Trauma Battlefield Artificial evolution Machine learning

Antagonism of Transcription Factor MYC2 by EdS1/PAd4 Complexes Bolsters Salicylic Acid defense in Arabidopsis Effector-Triggered Immunity

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Molecular Plant 2018年第8期11卷 1053-1066页

作者： Haitao Cui Jingde Qiu Yue Zhou deepak d. Bhandari Chunhui Zhao Jaqueline Bautor Jane E. Parker department of Plant-Microbe Interactions Max-Planck Institute for Plant Breeding Research Carl-von-Linne Weg 10 50829 Cologne Germany department of Plant developmental Biology Max-Planck Institute for Plant Breeding Research 50829 Cologne Germany Key Laboratory of Ministry of Education for Genetics Breeding and Multiple Utilization of Crops Plant Immunity Center Fujian Agriculture University Fuzhou 350002 China These authors contributed equaily to this article.

In plant immunity, pathogen-activated intracellular nucleotide binding/leucine rich repeat （NLR） receptors mobilize disease resistance pathways, but the downstream signaling mechanisms remain obscure. Enhanced disease susceptibility 1 （EdS1） controls transcriptional reprogramming in resistance triggered by Toll-lnterleukinl-Receptor domain （TIR）-family NLRs （TNLs）. Transcriptional induction of the salicylic acid （SA） hormone defense sector provides one crucial barrier against biotrophic pathogens. Here, we present genetic and molecular evidence that in Arabidopsis an EdS1 complex with its partner PAd4 inhibits MYC2, a master regulator of SA-antagonizing jasmonic acid （JA） hormone pathways. In the TNL immune response, EdSl/PAd4 interference with MYC2 boosts the SA defense sector independently of EdS1-induced SA synthesis, thereby effectively blocking actions of a potent bacterial JA mimic, coronatine （COR）. We show that antagonism of MYC2 occurs after COR has been sensed inside the nucleus but before or coincident with MYC2 binding to a target promoter, pANAC019. The stable interaction of PAd4 with MYC2 in planta is competed by EdS1-PAd4 complexes. However, suppression of MYC2-promoted genes requires EdS1 together with PAd4, pointing to an essential EdS1-PAd4 heterodimer activity in MYC2 inhibition. Taken together, these results uncover an immune receptor signaling circuit that intersects with hormone pathway crosstalk to reduce bacterial pathogen growth.

关键词： NLR receptor stress hormone network Pseudomonas syringae AvrRps4 RRS1/RPS4 coi1

Barnyard millet global core collection evaluation in the submontane Himalayan region of India using multivariate analysis

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The Crop Journal 2015年第6期3卷 517-525页

作者： Salej Sood Rajesh K.Khulbe Arun Kumar R. Pawan K. Agrawal Hari d.Upadhyaya Indian Council of Agricultural Research-Vivekananda Institute of Hill Agriculture International Crop Research Institute for the Semi-Arid Tropics (ICRISAT)

Barnyard millet(Echinochloa spp.) is one of the most underresearched crops with respect to characterization of genetic resources and genetic enhancement. A total of 95 germplasm lines representing global collection were evaluated in two rainy seasons at Almora,Uttarakhand, India for qualitative and quantitative traits and the data were subjected to multivariate analysis. High variation was observed for days to maturity, five-ear grain weight, and yield components. The first three principal component axes explained 73% of the total multivariate variation. Three major groups were detected by projection of the accessions on the first two principal components. The separation of accessions was based mainly on trait morphology. Almost all Indian and origin-unknown accessions grouped together to form an Echinochloa frumentacea group. Japanese accessions grouped together except for a few outliers to form an Echinochloa esculenta group. The third group contained accessions from Russia, Japan, Cameroon, and Egypt. They formed a separate group on the scatterplot and represented accessions with lower values for all traits except basal tiller number. The interrelationships between the traits indicated that accessions with tall plants, long and broad leaves, longer inflorescences, and greater numbers of racemes should be given priority as donors or parents in varietal development initiatives. Cluster analysis identified two main clusters based on agro-morphological characters.

关键词： Agro-morphological variation Barnyard millet core germplasm Cluster analysis Echinochloa spp Principal component analysis