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World Journal of Gastroenterology 2014年第3期20卷 829-842页

作者： Vivian W Huang Krista M reich Richard n Fedorak Division of Gastroenterology University of Alberta

AIM: To review the effectiveness of distance management methods in the management of adult inflammatory bowel disease (IBD) patients.

关键词： Telemanagement Telehealth Inflammatory bowel disease Distance management Self-management

Vitamin D improves inflammatory bowel disease outcomes:Basic science and clinical review

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World Journal of Gastroenterology 2014年第17期20卷 4934-4947页

作者： Krista M reich Richard n Fedorak Karen Madsen Karen I Kroeker Division of Gastroenterology University of AlbertaEdmontonAlberta T6G 2X8Canada

Vitamin D deficiency is commonly diagnosed among patients with inflammatory bowel disease (IBD). Patients with IBD are at risk of low bone density and increased fractures due to low vitamin D levels, long standing disease, and frequent steroid exposures; as a result, it is well established that vitamin D supplementation in this population is important. There is increasing support for the role of vitamin D in strengthening the innate immune system by acting as an immunomodulator and reducing inflammation in experimental and human IBD. The active form of vitamin D, 1,25(OH)D3, acts on T cells to promote T helper (Th)2/regulatory T responses over Th1/Th17 responses; suppresses dendritic cell inflammatory activity; induces antibacterial activity; and regulates cytokine production in favor of an anti-inflammatory response. Murine and human IBD studies support a therapeutic role of vitamin D in IBD. Risk factors for vitamin D deficiency in this population include decreased sunlight exposure, disease duration, smoking, and genetics. Vitamin D normalization is associated with reduced risk of relapse, reduced risk of IBD-related surgeries, and improvement in quality of life. Vitamin D is an inexpensive supplement which has been shown to improve IBD outcomes. However, further research is required to determine optimal serum vitamin D levels which will achieve beneficial immune effects, and stronger evidence is needed to support the role of vitamin D in inducing disease response and remission, as well as maintaining this improvement in patients’ disease states.

关键词： Vitamin D Inflammatory bowel disease Immune response Inflammation Cytokines Supplementation

Promise and pitfalls of modeling grassland soil moisture in a free-air CO_(2) enrichment experiment(BioCOn)using the SHAW model

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Pedosphere 2021年第5期31卷 783-795页

作者： Raquel H.FLInKER M.Bayani CARDEnAS Todd G.CALDWELL Gerald n.FLERCHInGER Roy RICH Peter B.reich Department of Geological Sciences The University of Texas at AustinAustin 78712(USA) Bureau of Economic Geology The University of Texas at AustinAustin 78713(USA) Agricultural Research Service United States Department of AgricultureBoise 83712(USA) Smithsonian Environmental Research Center Edgewater 20137(USA) Department of Forest Resources University of MinnesotaSt.Paul 55108(USA) Hawkesbury Institute for the Environment Western Sydney UniversitySydney 2753(Australia)

Free-air carbon dioxide(CO_(2))enrichment(FACE)experiments provide an opportunity to test models of heat and water flow under novel,controlled situations and eventually allow use of these models for hypothesis *** study assesses whether the United States Department of Agriculture SHAW(Simultaneous Heat and Water)numerical model of vertical one-dimensional soil water flow across the soil-plant-atmosphere continuum is able to adequately represent and explain the effects of increasing atmospheric CO_(2) on soil moisture dynamics in temperate *** in a FACE experiment,the Bio COn(Biodiversity,CO_(2),and nitrogen)experiment,in Minnesota,USA,were compared with results of vertical soil moisture *** scenarios represented by different plots were assessed:bare,vegetated with ambient CO_(2),and similarly vegetated with high CO_(2).From the simulations,the bare plot soil was generally the wettest,followed by a drier high-CO_(2) vegetated plot,and the ambient CO_(2) plot was the *** SHAW simulations adequately reproduced the expected behavior and showed that vegetation and atmospheric CO_(2) concentration significantly affected soil moisture *** differences in modeled soil moisture amongst the plots were largely due to transpiration,which was low with high CO_(2).However,the modeled soil moisture only modestly reproduced the ***,while SHAW is able to replicate and help broadly explain soil moisture dynamics in a FACE experiment,its application for point-and time-specific simulations of soil moisture needs further *** typical design of a FACE experiment makes the experimental observations challenging to model with a one-dimensional distributed *** addition,FACE instrumentation and monitoring will need improvement in order to be a useful platform for robust model *** after this can we recommend that models such as SHAW are adequate for process interpretation of datasets from FACE exp

关键词： carbon dioxide FACE experiment soil water flow vadose zone vegetation

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Effects of local neighbourhood diversity on crown structure and productivity of individual trees in mature mixed-species forests

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Forest Ecosystems 2021年第2期8卷 345-356页

作者： Louis Georgi Matthias Kunz Andreas Fichtner Karl Friedrich reich Anne Bienert Hans-Gerd Maas Goddert von Oheimb Technische Universität Dresden Institute of General Ecology and Environmental ProtectionPienner Straße 701737 TharandtGermany Leuphana University of Lüneburg Institute of EcologyUniversitätsallee 121335 LüneburgGermany Technische Universität Dresden Institute of Photogrammetry and Remote SensingHelmholtzstraße 1001069 DresdenGermany

Background:Species-specific genotypic features,local neighbourhood interactions and resource supply strongly influence the tree stature and growth *** mixed-species forests,diversity-mediated biomass allocation has been suggested to be a fundamental mechanism underlying the positive biodiversity-productivity *** evidence,however,is rare about the impact of local neighbourhood diversity on tree characteristics analysed at a very high level of *** address this issue we analysed these effects on the individual-tree crown architecture and tree productivity in a mature mixed forest in northern ***:Our analysis considers multiple target tree species across a local neighbourhood species richness gradient ranging from 1 to *** applied terrestrial laser scanning to quantify a large number of individual mature trees(n=920)at very high *** evaluated two different neighbour inclusion approaches by analysing both a fixed radius selection procedure and a selection based on overlapping *** and conclusions:We show that local neighbourhood species diversity significantly increases crown dimension and wood volume of target ***,we found a size-dependency of diversity effects on tree productivity(basal area and wood volume increment)with positive effects for large-sized trees(diameter at breast height(DBH)>40 cm)and negative effects for small-sized(DBHnalysis,the neighbour inclusion approach has a significant impact on the *** scientific studies and the validation of growth models we recommend a neighbour selection by overlapping crowns,because this seems to be the relevant scale at which local neighbourhood interactions *** local neighbourhood diversity promotes individual-tree productivity in mature European mixed-species forests,we conclude that a small-scale species mixture should be considered in management plans.

关键词： Biodiversity Tree growth Crown architecture Quantitative structure models Terrestrial laser scanning neighbour classification

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Empirical evaluation of confidence and prediction intervals for spatial models of forest structure in Jalisco,Mexico

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Journal of Forestry Research 2011年第2期22卷 159-166页

作者： Robin M.reich C.Aguirre-Bravo Vanessa A.Bravo Martin Mendoza Briseo Department of Forest and Rangeland Stewardship Colorado State UniversityFort CollinsCO 80523-1472 USA USDA Forest Service ArlingtonVA 22209-2131 USA Clegio de Postgraduados Campus MontecillosTexcocoMexico

In recent years there has been an increasing interest in developing spatial statistical models for data sets that are seemingly spatially *** lack of spatial structure makes it difficult,if not impossible to use optimal predictors such as ordinary kriging for modeling the spatial variability in the *** many instances,the data still contain a wealth of information that could be used to gain flexibility and precision in *** this paper we propose using a combination of regression analysis to describe the large-scale spatial variability in a set of survey data and a tree-based stratification design to enhance the estimation process of the small-scale spatial *** this approach,sample units（i.e.,pixel of a satellite image） are classified with respect to predictions of error attributes into homogeneous classes,and the classes are then used as strata in the stratified *** variables used as a basis of stratification included terrain data and satellite imagery.A decision rule was used to identify a tree size that minimized the error in estimating the variance of the mean response and prediction uncertainties at new spatial *** approach was applied to a set of n=937 forested plots from a state-wide inventory conducted in 2006 in the Mexican State of *** final models accounted for 62% to 82% of the variability observed in canopy closure（%）,basal area（m2·ha-1）,cubic volumes（m3·ha-1） and biomass（t·ha-1） on the sample *** spatial models provided unbiased estimates and when averaged over all sample units in the population,estimates of forest structure were very close to those obtained using classical estimates based on the sampling strategy used in the state-wide *** spatial models also provided unbiased estimates of model variances leading to confidence and prediction coverage rates close to the 0.95 nominal rate.

关键词： tree-based stratified design generalized least squares standardized mean squared error Landsat-7 ETM+

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Global leaf nitrogen and phosphorus stoichiometry and their scaling exponent

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national Science Review 2018年第5期5卷 728-739页

作者： Di Tian Zhengbing Yan Karl J.niklas Wenxuan Han Jens Kattge Peter B.reich Yongkai Luo Yahan Chen Zhiyao Tang Huifeng Hu Ian J.Wright Bernhard Schmid Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Max-Planck-Institute for Biogeochemistry State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Life Sciences Capital Normal University Department of Plant Biology Cornell University Department of Forest Resources University of Minnesota Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia10 Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Hawkesbury Institute for the Environment Western Sydney University Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural University

Leaf nitrogen(n) and phosphorus(P) concentrations constrain photosynthetic and metabolic processes,growth and the productivity of plants. Their stoichiometry and scaling relationships regulate the allocation of n and P from subcellular to organism, and even ecosystem levels, and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems. Prior work has revealed a general biogeographic pattern of leaf n and P stoichiometric relationships and shown that leaf n scales roughly as two-thirds the power of P. However, determining whether and how leaf n and P stoichiometries, especially their scaling exponents, change with functional groups and environmental conditions requires further verification. In this study, we compiled a global data set and documented the global leaf n and P concentrations and the n:P ratios by functional group, climate zone and continent. The global overall mean leaf n and P concentrations were 18.9 mg gand 1.2 mg g, respectively, with significantly higher concentrations in herbaceous than woody plants(21.72 mg gvs. 18.22 mg gfor n; and 1.64 mg gvs. 1.10 mg gfor P). Both leaf n and P showed higher concentrations at high latitudes than low latitudes. Among six continents, Europe had the highest n and P concentrations(20.79 and 1.54 mg g) and Oceania had the smallest values(10.01 and 0.46 mg g). These numerical values may be used as a basis for the comparison of other individual studies. Further, we found that the scaling exponent varied significantly across different functional groups,latitudinal zones, ecoregions and sites. The exponents of herbaceous and woody plants were 0.659 and0.705, respectively, with significant latitudinal patterns decreasing from tropical to temperate to boreal zones. At sites with a sample size ≥10, the values fluctuated from 0.366 to 1.928, with an average of *** factors including the intrinsic attributes of different life forms, P-related growth rates and relative nutrient availa

关键词： leaf nitrogen phosphorus stoichiometry scaling exponent functional group biogeography

Reproducibility of Test-Retest Cortical Evoked Responses in Patients with Focal Epilepsy

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Journal of Behavioral and Brain Science 2023年第1期13卷 1-13页

作者： Mackenzie C. Cervenka Monika Rozycka Erik Sass Dana Boatman.reich Department of neurology Johns Hopkins School of Medicine Baltimore USA Department of Otolaryngology Johns Hopkins School of Medicine Baltimore USA

This exploratory study examined the short-term reliability of cortical auditory evoked responses recorded from patients undergoing whole-head scalp elec-troencephalography (EEG) monitoring to assess their candidacy for surgical treatment of intractable focal seizures. Participants were 26 patients with either left-sided (n = 13) or right-sided focal epilepsy admitted to the hospital for continuous scalp EEG monitoring for possible epilepsy surgery planning. Cortical auditory evoked responses were recorded over multiple days from scalp EEG electrodes using tones presented binaurally in a passive oddball paradigm. Test-retest intervals were 1 - 6 days (mean 2 days). Test-retest reproducibility of the auditory n1 response was assessed by paired t-test (latency) and cross-correlation analysis (amplitude and latency). Within-patient comparisons of test-retest auditory n1 peak latencies revealed no significant differences. The cross-correlation coefficient indicated high test-retest reproducibility of the n1 waveform (rcc = 0.88). Seizure lateralization was not associated with asymmetries in n1 latencies or amplitudes. An n1 amplitude asymmetry (right > left) in patients with focal seizures originating from the left hemisphere was initially observed, but disappeared when patients with prior resections were excluded, suggesting that reduced left hemisphere tissue volume may account for the smaller n1 amplitudes. Test-retest reliability of cortical auditory evoked responses was unexpectedly high in patients with focal epilepsy regardless of seizure lateralization or localization. These findings challenge the view that neural responses are intrinsically unstable (unreliable) in patients with seizures.

关键词： Auditory Evoked Response Seizure Epilepsy Reproducibility Reliability

Particle Swarm Optimization of Printing Parameters for Open-source TIG-based Metal 3D Printing

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Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers) 2022年第4期1卷 27-35页

作者： Shane Oberloier Wilson J Holmes Luke A reich Joshua M Pearce Department of Electrical&Computer Engineering Michigan Technological UniversityHoughtonMI 49931USA Department of Mechanical Engineering–Engineering Mechanics Michigan Technological UniversityHoughtonMI 49931USA Department of Electrical&Computer Engineering Ivey Business SchoolWestern UniversityLondonN6A 5B9Canada

Proprietary metal 3D printing is still relegated to relatively expensive systems that have been constructed over years of expensive trial-and-error to obtain optimum 3D printing ***-cost open-source metal 3D printers can potentially democratize metal additive manufacturing;however,significant resources are required to redevelop optimal printing parameters for each metal on new *** this study,the particle swam optimization(PSO)experimenter,a free and open-source software package,is utilized to obtain the optimal printing parameters for a tungsten inert gas-based metal open source 3D *** software is a graphical user interface implementation of the PSO method and is designed specifically for hardware-in-loop *** uses the input of experimental variables and their respective ranges,and then proposes iterations for experiments.A custom fitness function is defined to characterize the experimental results and provide feedback to the algorithm for low-cost metal additive *** separate trials are performed to determine the optimal parameters for 3D ***,an experiment is designed to deposit and optimize the parameters for a single ***,the parameters for a single-layer plane is optimized ***,the optimal printing parameters for a cube is determined ***,the line optimization experiment is revised and reconducted using different shield gas *** results and limitations are presented and discussed in the context of expanding wire arc additive manufacturing to more systems and material classes for distributed digital manufacturing.

关键词： Metal 3D printing Additive manufacturing Tungsten inert gas welding TIG welding Particle swarm optimization RepRap

FLAIR~*:一种显示脑白质病变和脑实质内静脉的综合MR对比技术

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国际医学放射学杂志 2013年第1期 80-80页

作者： P.Sati I.C.George C.D.Shea M.I.Gaitán D.S.reich 路丽 Translational neuroradiology Unit Neuroimmunology BranchNational Institute of Neurological Disorders and StrokeNational Institutes of Health9000 Rockville PikeBuilding 10/5C205BethesdaMD 20892-1584

目的评价一种名为FLAIR*的MRI对比技术,它在一幅影像内同时具有T2FLAIR和T2*对比的优势,可用于评价脑白质疾病(如多发性硬化)。材料与方法此前瞻性研究符合HIPAA原则,并获得单位伦理委员会批准。10例临床确诊为多发性硬化的病人(男8例,... 详细信息

目的评价一种名为FLAIR*的MRI对比技术,它在一幅影像内同时具有T2FLAIR和T2*对比的优势,可用于评价脑白质疾病(如多发性硬化)。材料与方法此前瞻性研究符合HIPAA原则,并获得单位伦理委员会批准。10例临床确诊为多发性硬化的病人(男8例,女2例,平均年龄41岁)签署知情同意书后进行3.0TMRI检查。在注射对比剂后获取T2FLAIR图像和T2*多次激发EPI序列影像,从而得到各向同性体素(0.55mm×0.55mm×0.55mm)的高分辨力FLAIR*影像。对影像质量、病灶和静脉的清晰度进行定量评价。计算正常脑白质与脑脊液、病灶和静脉的对比噪声比(CnR)。采用配对t检验评价受试者在不同成像方式中CnR的差异。结果 3.0TMRI可获得高质量的大脑FLAIR*影像,提高病灶和静脉的清晰度。病灶与正常脑白质、正常脑白质与静脉之间的CnR在FLAIR*序列明显高于T2FLAIR序列(P<0.0001)。FLAIR*影像中的表现包括脑内各部位病灶内的静脉和部分脑白质病灶周围的环状低信号。结论 3.0TMRI获得的各向同性高分辨FLAIR*影像提高了脑白质病变和脑实质内静脉的对比,在临床上能很好地评价脑白质异常与静脉血管的关系。

关键词： FLAIR 病灶脑白质病变静脉 MR 脑实质