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Interiors now!

Spatial and temporal variability of soil freeze-thaw cycling across Southern Alberta, Canada

作者： (author.)phillips Ian

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Agricultural Sciences 2011年第4期2卷 392-405页

作者： Andrew j. phillips Nathaniel K. Newlands 不详

Soil freeze-thaw cycles play an important role in all aspects of agro-ecosystems, such as crop productivity, the evolution of the soil matrix, including trace-gas emissions. In regions that experience synoptic weather conditions throughout the winter, freeze-thaw cycles generally occur in one of two categories;seasonal or winter cycles. Current soil vegetation atmosphere models (SVAT’s) often include a heat-transport soil freeze-thaw algorithm, but lack detail on complex interactions between the main driving variables. Boundary conditions for these models are often based only on a few climate variables and typically lack regional context. A nested statistical analysis was applied to identify the optimal set of environmental variables (via a stepwise regression selection procedure) to track soil freeze-thaw dynamics. Historical data collected between the years 2006-2009, for 17 long-term climate stations distributed across southern Alberta Canada was utilized. Cross-correlation between wind speed and maximum air temperature identified Chinook-driven freeze-thaw events, with such interaction varying significantly across the region and by soil depth. Climate-soil interactions were most significant predictors of soil temperature during winter months. The seasonal freeze-thaw cycle is estimated to vary between 112 - 131 days, consisting of 12 - 20 winter cycles (1 cm depth), and 1-5 winter cycles (5 cm depth) with average lag time of 26 - 112 days. Freeze-thaw prediction was greatly improved when higher-order climate interaction terms were considered. Our findings highlight the importance for soil-water and more complex ecosystem, SVAT models to better resolve regional-driven climatic trends. Alongside improved representation of regional trends aimed at reducing model-based uncertainty, such efforts are expected to, in tandem, help advance the geostatistical design, and implementation of agroenvironmental monitoring systems that combine in-situ and satellite/remote-sensi

关键词： Freeze-Thaw Soil Temperature Agro-Ecosystem Modeling Regional Climate Soil Science

Secreted frizzled related-protein 2(Sfrp2)deficiency decreases adult skeletal stem cell function in mice

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Bone Research 2021年第4期9卷 606-617页

作者： Luis Fernandez de Castro Brian丄Sworder Byron Mui Kathryn Futrega Agnes Berendsen Matthew D.phillips Nathan j.Burbach Natasha Cherman Sergei Kuznetsov Yankel Gabet Kenn Holmbeck pamela G.Robey Skeletal Biology Section National Institute of Dental and Craniofacial ResearchNational Institutes of HealthDepartment of Health and Human ServicesNational Institutes of HealthBethesdaMDUSA Department of Molecular Medicine Boston UniversityBostonMAUSA School of Dentistry University of Minnesota-Twin CitiesMinneapolisMNUSA Department of Anatomy and Anthropology Sackler Faculty of MedicineTel Aviv UniversityTel Aviv-YafoIsrael

In a previous transcriptomic study of human bone marrow stromal cells(BMSCs,also known as bone marrow-derived^mesenchymal stem cells#,)/SFRp2 was highly over-represented in a subset of multipotent BMSCs(skeletal stem cells,SSCs),which recreate a bone/marrow organ in an in vivo ectopic bone formation *** modulate WNT signaling,which is essential to maintain skeletal homeostasis,but the specific role of SFRp2 in BMSCs/SSCs is ***,we evaluated Sfrp2 deficiency on BMSC/SSC function in models of skeletal organogenesis and *** skeleton of Sfrp2-def\c\ent(KO)mice is overtly normal;but their BMSCs/SSCs exhibit reduced colony-forming efficiency,reflecting low SSC self-renewal/***2 KO BMSCs/SSCs formed less trabecular bone than those from WT littermates in the ectopic bone formation ***,regeneration of a cortical drilled hole defect was dramatically impaired in Sfrp2 KO ***2-deficient BMSCs/SSCs exhibited poor in vitro osteogenic differentiation as measured by Runx2 and Osterix expression and calcium ***,activation of the Wnt co-receptor;Lrp6,and expression of Wnt target genes,Axin2,C-myc and Cyclin Dl,were reduced in Sfrp2-deficient BMSCs/*** of recombinant Sfrp2 restored most of these activities,suggesting that Sfrp2 acts as a Wnt *** demonstrate that Sfrp2 plays a role in self-renewal of SSCs and in the recruitment and differentiation of adult SSCs during bone ***2 is also a useful marker of BMSC/SSC multipotency,and a factor to potentially improve the quality of ex vivo expanded BMSC/SSC products.

关键词： skeletal impaired healing

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静电场驱动下液体薄膜的几何形状

应用数学和力学 2011年第8期32卷 973-980页

作者： E.M.田 T.p.斯沃博德内 j.D.菲利普斯莱特州立大学数学与统计学院

利用六边形-俯视图的弱非线性稳定性分析和数值仿真,在电场作用下,研究高分子薄膜表面静态模式的发展过程.在无限空间域上,空间和高分子薄膜之间的界面,由薄膜方程给出其随时间的演变,综合考虑了电力的驱动和表面张力的传播.非线性界面... 详细信息

利用六边形-俯视图的弱非线性稳定性分析和数值仿真,在电场作用下,研究高分子薄膜表面静态模式的发展过程.在无限空间域上,空间和高分子薄膜之间的界面,由薄膜方程给出其随时间的演变,综合考虑了电力的驱动和表面张力的传播.非线性界面的增长包括:波幅方程的增长,以及在准对规律方向上,一维结构的叠合.模式的选择由亚临界不稳定性机理确定,高分子薄膜的相对厚度在其中起着决定性的作用.

关键词：薄膜模式的形成电流体动力学不稳定性

Ranking higher taxa using divergence times:a case study in Dothideomycetes

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Fungal Diversity 2017年第3期84卷 75-99页

作者： jian-Kui Liu Kevin D.Hyde Rajesh jeewon Alan j.L.phillips Sajeewa S.N.Maharachchikumbura Martin Ryberg Zuo-Yi Liu Qi Zhao Key Laboratory for plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Guizhou Institute of Biotechnology Guizhou Academy of Agricultural SciencesGuiyang 550006People’s Republic of China Guizhou Key Laboratory of Agricultural Biotechnology Guizhou Academy of Agricultural SciencesGuiyang 550006People’s Republic of China Center of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai 57100Thailand Departmental of Health Sciences Faculty of ScienceUniversity of MauritiusReduitMauritius University of Lisbon Faculty of SciencesBiosystems and Integrative Sciences InstituteCampo Grande1749-016 LisbonPortugal Department of Crop Sciences College of Agricultural and Marine SciencesSultan Qaboos UniversityPO Box 8123 Al KhoudOman Department of Organismal Biology Uppsala UniversityNorbyvägen 18D75236 UppsalaSweden

The current classification system for the recognition of taxonomic ranks among fungi,especially at highranking level,is *** the development of molecular approaches and the availability of fossil calibration data,the use of divergence times as a universally standardized criterion for ranking taxa has now become *** can therefore date the origin of Ascomycota lineages by using molecular clock methods and establish the divergence times for the orders and families of *** chose Dothideomycetes,the largest class of the phylum Ascomycota,which contains 32 orders,to establish ages at which points orders have split;and pleosporales,the largest order of Dothideomycetes with 55 families,to establish family divergence *** have assembled a multi-gene data set(LSU,SSU,TEF1 and RpB2)from 391 taxa representing most family groups of Dothideomycetes and utilized fossil calibration points solely from within the ascomycetes and a Bayesian approach to establish divergence times of Dothideomycetes *** separated datasets were analysed:(i)272 taxa representing 32 orders of Dothideomycetes were included for the order level analysis,and(ii)191 taxa representing 55 families of pleosporales were included for the family level *** results indicate that divergence times(crown age)for most orders(20 out of 32,or 63%)are between 100 and 220 Mya,while divergence times for most families(39 out of 55,or 71%)are between 20 and 100 *** believe that divergence times can provide additional evidence to support establishment of higher level taxa,such as families,orders and *** advantage of this added approach,we can strive towards establishing a standardized taxonomic system both within and outside *** this study we found that molecular dating coupled with phylogenetic inferences provides no support for the taxonomic status of two currently recognized orders,namely Bezerromycetales and Wiesneriomycetales and these are treated as sy

关键词： BEAST Clade age Classification Calibration Family Order phylogeny pleosporales

用脉冲辐解技术研究菲醌的单电子氧化(英文)

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辐射研究与辐射工艺学报 2003年第1期21卷 29-34页

作者：包华影 S.Navaratnam B.j.parsons G O.phillips 北京师范大学化学系北京100875 North East Wales Institute

采用脉冲辐解技术,以羟基自由基和硫酸根自由基作为氧化剂,研究了9,10-菲醌(phQ)在水溶液中的单电子氧化行为,获取了瞬态产物的吸收光谱和有关动力学数据。在中性pH条件下,phQ 与羟基自由基以(1.5±0.2)×1010 dm3·mol-1·s-1的速率反... 详细信息

采用脉冲辐解技术,以羟基自由基和硫酸根自由基作为氧化剂,研究了9,10-菲醌(phQ)在水溶液中的单电子氧化行为,获取了瞬态产物的吸收光谱和有关动力学数据。在中性pH条件下,phQ 与羟基自由基以(1.5±0.2)×1010 dm3·mol-1·s-1的速率反应,生成一个初级瞬态产物。该瞬态产物的吸收光谱呈现出位于370nm的吸收峰和在较长波长下的一个宽吸收带。进一步实验观察到,随着短波长区初级吸收的衰减,可见光区的吸收同步增加,在400nm处形成最大吸收峰,并产生以500nm为中心的宽吸收带,表明次级瞬态产物的形成。pH9.9条件下得到的结果与中性pH的一致。降低pH至2—4,尽管初始瞬态吸收谱也呈现出位于370nm的最大吸收峰,但伴随着初始吸收的哀减,没有观察到可见区域吸收的增加。在中性pH条件下,硫酸根自由基与phQ反应的速率常数测定为(4.0±0.6)×109dm3·mol-1·s-1,生成的瞬态吸收谱与氢氧自由基反应得到的次级吸收谱一致,呈现以400nm和500nm为中心的两个吸收带。基于光谱的相似性和动力学分析,以及羟基自由基和硫酸根自由基的特性,本工作推断反应机理如下:phQ羟基自由基反应首先生成OH加成产物,OH加成产物脱水生成阳离子自由基:阳离子自由基办可通过硫酸根自由基的氧化直接产生。

关键词：脉冲辐解单电子氧化 9,10-菲醌吸收光谱动力学分析

农业综合企业能供养30亿新增人口吗?能拯救我们的地球吗? 格里姆斯GLIMpSE^(TM)透视未来

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饲料研究 2014年第2期37卷 66-71页

作者： Aidan j.Connolly Kate phillips-Connolly 奥特奇公司爱尔兰迈克尔墨菲特都柏林大学商学院爱尔兰Trinity学院全球贸易中心系统

供养未来40年新增的30亿人口这是一个极大的挑战,完全属于"不可思议的问题"。农业综合企业一直被认为是问题的一部分,以牺牲人类长远的发展和环境为代价追求短期的增长。我们认为,私人企业参与的,以市场为导向的解决方案是应对这一挑战... 详细信息

供养未来40年新增的30亿人口这是一个极大的挑战,完全属于"不可思议的问题"。农业综合企业一直被认为是问题的一部分,以牺牲人类长远的发展和环境为代价追求短期的增长。我们认为,私人企业参与的,以市场为导向的解决方案是应对这一挑战不可或缺的组成部分。文章参考了大量的文献资料,采访了由24位专家组成的来自农业综合企业的专家组成员,我们确定了7大障碍,这些障碍被认为是我们供养地球90亿人口能力的影响因素。本文以7大障碍的首个字母组成"GLIMpSE",以帮助我们了解和透视这些障碍,识别和确定我们的机遇。这是向利用市场力量迈出的至关重要的一步,藉此,农业综合企业在农业可以集我们的创造力、决断力和科学技术于一身,如同巴西"塞拉奇迹"一样,迎接2050年供应全球30亿新增人口的挑战。

关键词：农业综合企业食品不可思议的问题

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改进的排气温度传感器

小型内燃机与车辆技术 1982年第3期 80-82页

作者： p.j.Sacchetti ,D.R.phillips ,陆靖基

一种比率式的温度传感器已经研制成功,这种传感器不用辅助放大器或信号调节电子装置就能直接测量汽车排气温度。

关键词：圆盘蠕变双金属电子装置信号调节精密合金温度传感器滞后作用电位计电位差计分解图无补偿输出稳定性挠曲排气温度高温传感器

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