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Experimental evidence that soil heterogeneity enhances plant diversity during community assembly

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Journal of Plant Ecology 2014年第5期7卷 461-469页

作者： Brandon m.Williams gregory R.Houseman Department of Biological Sciences Wichita State University1845 FairmountWichitaKS 67260USA

Aims Environmental heterogeneity is a primary mechanism explain-ing species coexistence and extant patterns of *** strong theoretical support and ample observational evidence,few experimental studies in plant communities have been able to demonstrate a causal link between environmental heterogene-ity and plant *** lack of experimental evidence sug-gests that either fine-scale heterogeneity has weak effects on plant diversity or previous experiments have been unable to effectively manipulate ***,we utilize a unique soil manipu-lation to test whether fine-scale soil heterogeneity will increase plant richness through species sorting among experimental patch *** This experiment was conducted in the tallgrass prairie region of south-central Kansas,*** utilized the inherent variation found in the vertical soil profile,which varied in both biotic and abiotic characteristics,and redistributed these strata into either homoge-neous or heterogeneous spatial arrangements in 2.4×2.4 m *** the soil manipulation,34 native prairie species were sown into all *** conducted annual censuses at peak biomass to quantify species composition and plant density by species within the experimental *** Findings After 2 years,species richness was significantly higher in heteroge-neous relative to homogeneous plots and this pattern was independ-ent of total plant *** the heterogeneous plots,13 species had higher establishment in a specific patch type representing one of the three soil ***,no species had greater estab-lishment in the mixed stratum,which comprised the homogene-ous plots,relative to the heterogeneous *** species sorting patterns suggest that fine-scale heterogeneity creates opportunities for plant establishment due to niche differences,which translates into increased plant diversity at the plot *** richness was more strongly related to plant density among patch

关键词： environmental heterogeneity species richness species sorting community assembly niche theory neutral theory

Oncogene interactions are required for glioma development and progression as revealed by a tissue specific transgenic mouse model

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Chinese Journal of Cancer 2011年第3期30卷 163-172页

作者： Lynette m. moore Kristen m. Holmes gregory N. Fuller Department of Pathology the University of Texas M. D. Anderson Cancer Center

The aggressive and invasive nature of brain tumors has hampered progress in the design and implementation of efficacious therapies. The recent success of targeted therapies in other tumor types makes this an attractive area for research yet complicating matters is the ability of brain tumors to circumvent the targeted pathways to develop drug resistance. Effective therapies will likely need to target more than one signaling pathway or target multiple nodes within a given pathway. Key to identifying these targets is the elucidation of the driver and passenger molecules within these pathways. Animal models provide a useful tool with many advantages in the study of these pathways. These models provide a means to dissect the critical components of tumorigenesis, as well as serve as agents for preclinical testing. This review focuses on the use of the RCAS/tv-a mouse model of brain tumors and describes their unique ability to provide insight into the role of oncogene cooperation in tumor development and progression.

关键词：转基因小鼠模型癌基因组织特异性神经胶质瘤相互作用靶向治疗脑肿瘤信号通路

Acrylamide fragment inhibitors that induce unprecedented conformational distortions in enterovirus 713C and SARS-CoV-2 main protease

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Acta Pharmaceutica Sinica B 2022年第10期12卷 3924-3933页

作者： Bo Qin gregory B.Craven Pengjiao Hou Julian Chesti Xinran Lu Emma S.Child Rhodri m.L.morgan Wenchao Niu Lina Zhao Alan Armstrong David J.mann Sheng Cui NHC Key Laboratory of Systems Biology of Pathogens Institute of Pathogen BiologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100076China Department of Life Sciences Imperial College LondonSouth Kensington CampusLondon SW72AZUK Department of Chemistry Imperial College LondonMolecular Sciences Research HubWhite City CampusWood LaneLondon W120BZUK CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy PhysicsUniversity of Chinese Academy of SciencesBeijing 100049China

RNA viruses are critically dependent upon virally encoded proteases to cleave the viral polyproteins into functional *** of these proteases exhibit a similar fold and contain an essential catalytic cysteine,offering the opportunity to inhibit these enzymes with electrophilic small *** we describe the successful application of quantitative irreversible tethering(qIT)to identify acrylamide fragments that target the active site cysteine of the 3C protease(3Cpro)of Enterovirus 71,the causative agent of hand,foot and mouth disease in humans,altering the substrate binding ***,we re-purpose these hits towards the main protease(mpro)of SARS-CoV-2 which shares the 3C-like fold and a similar active *** hit fragments covalently link to the catalytic cysteine of mpro to inhibit its *** demonstrate that targeting the active site cysteine of mpro can have profound allosteric effects,distorting secondary structures to disrupt the active dimeric unit.

关键词： SARS-CoV-2 Protease inhibitors Covalent fragments Allosteric inhibition EV71

Three-year outcomes of patients with non-valvular atrial fibrillation: the COOL-AF registry

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Journal of Geriatric Cardiology 2023年第3期20卷 163-173页

作者： Rungroj Krittayaphong Satchana Pumprueg Pontawee Kaewkumdee Ahthit Yindeengam gregory YH Lip Division of Cardiology Department of MedicineFaculty of Medicine Siriraj HospitalMahidol UniversityBangkokThailand Liverpool Centre for Cardiovascular Science University of Liverpool and Liverpool Heart&Chest HospitalLiverpoolUnited Kingdom Department of Clinical medicine Aalborg UniversityAalborgDenmark

BACKGROUND Clinical outcomes of patients with non-valvular atrial fibrillation(AF)in Asian populations may be different from *** this study,we aimed to determine the incidence of ischemic stroke/systemic embolism(SSE),major bleeding,and death,and the predictors for clinical outcomes in a contemporary Asian cohort of newly diagnosed AF *** This is a prospective multicenter nationwide registry of patients with AF from 27 hospitals in *** data and follow-up data were collected every 6 months until 3 *** collections included demographic,medical history,laboratory,and medication *** outcomes were SSE,major bleeding,and all-cause *** rates for each clinical outcome were calculated and presented as rate per 100 *** and multivariate analysis was performed to determine the independent predictors for clinical *** There was a total of 3405 patients:mean age was 67.8±11.3 years,1981(58.2%)were *** 30.8±9.7 months follow-up,there was a total of 132 SSE(3.9%),191 major bleeding(5.6%),and 357 all-cause deaths(10.5%).The incidence rates of SSE,major bleeding,and death were 1.56(1.30-1.84),2.26(1.96-2.61),and 4.17(3.33-4.25),per 100 person-years *** predictors for clinical outcomes were age,type of AF,and the presence of comorbid *** The incidence rate of SSE,major bleeding,and death remains high reflecting the unmet needs in AF management。

关键词： patients fibrillation mortality

Natural Variation in Tomato Reveals Differences in the Recognition of AvrPto and AvrPtoB Effectors from Pseudomonas syringae

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molecular Plant 2016年第5期9卷 639-649页

作者： Christine m. Kraus Kathy R. munkvold gregory B. martin Boyce Thompson Institute for Plant Research Ithaca NY 14853 USA Plant Pathology and Plant-microbe Biology Section School of Integrative Plant Science Cornell University Ithaca NY 14853 USA Beckman Coulter Indianapolis IN 46268 USA

The Pto protein kinase from Solanum pimpinellifolium interacts with Pseudomonas syringae effectors AvrPto or AvrPtoB to activate effector-triggered immunity. The previously solved crystal structures of the AvrPto-Pto and AvrPtoB-Pto complexes revealed that Pro binds each effector through both a shared and a unique interface. Hera we use natural variation in wild species of tomato to further investigate Pto recognition of these two effectors. One species, Solanum chmielewskU, was found to have many accessions that recognize only AvrPtoB. The Pto ortholog from one of these accessions was responsible for recognition of AvrPtoB and it differed from Solanum pimpinellifolium Pto by only 14 amino acids, including two in the AvrPto-specific interface, glutamate-49/glycine-51. Converting these two residues to those in Pro （histidine-49/valine-51） did not restore recognition of AvrPto. Subsequent experiments revealed that a single substitution of a histidine-to-aspartate at position 193 in Pto, which is not near the AvrPto- specific interface, was sufficient for conferring recognRion of AvrPto in plant cells. The reciprocal substi- tution of aspartate-to-histidine-193 in Pto abolished AvrPto recognition, confirming the importance of this residue. Our results reveal new aspects about effector recognition by Pto and demonstrate the value of using natural variation to understand the interaction between resistance proteins and pathogen effectors.

关键词： Effector-triggered immunity natural variation plant immunity Pseudomonas syringae Pto tomato

A 2-D Kinetic Theory for Flows of monodomain Polymer-Rod Nanocomposites

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Communications in Computational Physics 2010年第2期7卷 250-282页

作者： m.gregory Forest Qingqing Liao Qi Wang Department of mathematics University of North Carolina at Chapel HillChapel HillNC 27599USA Department of mathematics University of South CarolinaColumbiaSC 29208USA Department of mathematics and NanoCenter at USC University of South CarolinaColumbiaSC 29208USA

We merge classical kinetic theories [m. Doi and S. F. Edwards, The Theoryof Polymer Dynamics, 1986] for viscous dispersions of rigid rods, extended to semi-flexibility [A. R. Khokhlov and A. N. Semenov, macromolecules, 17 (1984), pp. 2678-2685], and for Rouse flexible chains to model the hydrodynamics of polymer nano-rodcomposites (PNCs). A mean-field potential for the polymer-rod interface provides thekey coupling between the two phases. We restrict this first study to two-dimensionalconformational space. We solve the coupled set of Smoluchowski equations for threebenchmark experiments. First we explore how rod semi-flexibility and the polymer-rod interface alter the Onsager equilibrium phase diagram. Then we determine mon-odomain phase behavior of PNCs for imposed simple elongation and shear, respec-tively. These results inform the effects that each phase has on the other as parametricstrengths of the interactions are varied in the context of the most basic rheological ex-periments.

关键词： Kinetic theory polymer nanorod nanocomposites monodomains equilibrium elon-gation shear

Holed Nanostructures Formed by Aluminum Droplets on a GaAs Substrate

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Nano Research 2010年第7期3卷 490-495页

作者： Alvason Zhenhua Li Zhiming m.Wang Jiang Wu gregory J.Salamo Institute of Nanoscale Science and Engineering University of ArkansasFayettevilleArkansas 72701USA

We have studied the morphology evolution of holed nanostructures formed by aluminum droplet epitaxy on a GaAs *** outer rings with concentric inner holed rings were ***,an empirical equation to describe the size distribution of the outer rings in the holed nanostructures has been *** contour line generated by the equation provides physical insights into quantum ring formation by droplets of groupⅢmaterials onⅢ-Ⅴsubstrates.

关键词： Droplet epitaxy aluminum droplets mBE GaAs holed nanostructures

The role of endoscopy in the management of hereditary diffuse gastric cancer syndrome

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World Journal of Gastroenterology 2019年第23期25卷 2878-2886页

作者： Shria Kumar Jessica m Long gregory G Ginsberg Bryson W Katona Division of Gastroenterology University of Pennsylvania Perelman School of MedicinePhiladelphiaPA 19104United States Division of Hematology and Oncology University of Pennsylvania Perelman School of MedicinePhiladelphiaPA 19104United States

Hereditary diffuse gastric cancer(HDGC) syndrome is an inherited cancer risk syndrome associated with path-ogenic germline CDH1 variants. Given the high risk for developing diffuse gastric cancer, CDH1 carriers are recommended to undergo prophylactic total gastrectomy for cancer risk reduction. Current guidelines recommend upper endoscopy in CDH1 carriers prior to surgery and then annually for individuals deferring prophylactic total *** of individuals from HDGC families without CDH1 pathogenic variants remains less clear, and management of families with CDH1 pathogenic variants in the absence of a family history of gastric cancer is particularly problematic at present. Despite adherence to surveillance protocols, endoscopic detection of cancer foci in HDGC is suboptimal and imperfect for facilitating decision-making. Alternative endoscopic modalities, such as chromoendoscopy,endoscopic ultrasound, and other non-white light methods have been utilized,but are of limited utility to further improve cancer detection and risk stratification in HDGC. Herein, we review what is known and what remains unclear about endoscopic surveillance for HDGC, among individuals with and without germline CDH1 pathogenic variants. Ultimately, the use of endoscopy in the management of HDGC remains a challenging arena, but one in which further research to improve surveillance is crucial.

关键词： CDH1 gene Hereditary diffuse gastric cancer Gastric cancer Endoscopic screening Endoscopy

modelling the smart farm

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Information Processing in Agriculture 2017年第3期4卷 179-187页

作者： michael J.O’Grady gregory m.P.O’Hare School of Computer Science University College DublinBelfieldDublin 4Ireland Earth Institute University College DublinBelfieldDublin 4Ireland

Smart farming envisages the harnessing of Information and Communication Technologies as an enabler of more efficient,productive,and profitable farming *** technologies do not suffice on their own;rather they must be judiciously combined to deliver meaningful information in near ***-support tools incorporating models of disparate farming activities,either on their own or in combination with other models,offer one popular approach;exemplars include GPFARm,APSIm,GRAZPLAN amongst many *** models tend to be generic in nature and their adoption by individual farmers is *** technologies offer an opportunity to remedy this situation;farm-specific models that can reflect near real-time events become tractable using such *** on the development,and application of farm-specific models is at a very early *** paper thus presents an overview of models within the farming enterprise;it then reviews the state-of the art in smart technologies that promise to enable a new generation of enterprise-specific models that will underpin future smart farming enterprises.

关键词： Smart agriculture modelling Sensing Internet of things