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Managing water for life

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Frontiers of Environmental Science & Engineering 2012年第2期6卷 255-264页

作者： daniel p.LOUCKS Haifeng JIA Civil and Environmental Engineering Comell UniversityIthaca NY 14853USA School of Environment Tsinghua UniversityBeijing 100084China

Water is essential for life. In spite of the entire engineering infrastructure devoted to the treatment, regulation and beneficial uses of water, occasionally sufficient quantities and qualities of water become scarce. When this happens, just how do we decide how much less water to allocate to all of us and the activities we engage in to sustain and enhance our quality of life？ This paper addresses some of the complexities of answering such a question, especially as society increasingly recognizes the need to provide flow regimes that will maintain healthy aquatic and floodplain ecosystems that also impact the economic, physical and even the spiritual quality of our lives. For we depend on these ecosystems to sustain our wellbeing. We are indeed a part of our ecosystems. We depend upon on aquatic ecosystems to moderate river flow qualities and quantities, reduce the extremes of floods and droughts, reduce erosion, detoxify and decompose water- borne wastes, generate and preserve flood plain soils and renew their fertility, regulate disease carrying organisms, and to enhance recreational benefits of river systems. This question of deciding just how much water to allocate to each water user and for the maintenance of viable aquatic ecosystems, especially when there is not enough, is a complex, and largely political, issue. This issue is likely to become even more complex and political and contentious in the future as populations grow and as water quantities and their qualities become even more variable and uncertain.

关键词： water stress aquatic ecosystems sustainablewater resource allocations ecosystem water requirements

Comparison of reduced point charge models of proteins: Molecular Dynamics simulations of Ubiquitin

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Science China Chemistry 2014年第10期57卷 1340-1354页

作者： LEHERTE Laurence VERCAUTEREN daniel p. Unité de Chimie physique Théorique et Structurale Laboratoire de Physico-Chimie Informatique Namur MEdicine & Drug Innovation Center (NAMEDIC) Department of Chemistry University of Namur Rue de Bruxelles 61 B-5000 Namur Belgium

Reduced point charge models of amino acids are used to model Ubiquitin （pDB： 1UBQ）. They are designed （i） from local ex- tremum positions in charge density （CD） distribution functions built from the poisson equation applied to smoothed molecular electrostatic potential functions, or （ii） from local maximum positions in promolecular electron density distribution （ED） func- tions. Charge values are fitted versus all-atom Amber99 molecular electrostatic potentials. The program GROMACS is used to generate molecular dynamics trajectories of the protein, under various implementation schemes, solvation, and temperature conditions. point charges that are not located on atoms are considered as virtual sites with a null mass and radius. The results illustrate that secondary structure is best preserved with the CD-based model at low temperatures and in vacuum. This indi- cates that local potential energy wells are consistent with the all-atom model. However, at room temperature, the structure is best conserved when point charges are forced to be located on atoms, due to a better description of the Coulomb l-4 energy terms. The ED-based model, generated at a lower resolution, led to the largest discrepancies versus the all-atom case. The CD-based model allows the formation of protein-water H-bonds with geometrical properties similar to the all-atom ones. Con- trarily, intra-molecular H-bonds are not well described. Structural, thermodynamical, and dynamical properties of proteins modelled with reduced point charge models are also significantly affected by the choice of the solvent force field.

关键词： molecular electrostatic potential electron density smoothing of molecular fields critical points point charge model protein Ubiquitin

The FLOWERING LOCUS T/TERMINAL FLOWER 1 Gene Family： Functional Evolution and Molecular Mechanisms

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Molecular plant 2015年第7期8卷 983-997页

作者： daniel p. Wickland Yoshie Hanzawa Department of Crop Sciences University of Illinois at Urbana-Champaign Urbana IL 61801 USA

In plant development, the flowering transition and inflorescence architecture are modulated by two homol- ogous proteins, FLOWERING LOCUS T （FT） and TERMINAL FLOWER 1 （TFL1）. The florigen FT promotes the transition to reproductive development and flowering, while TFL1 represses this transition. Despite their importance to plant adaptation and crop improvement and their extensive study by the plant community, the molecular mechanisms controlling the opposing actions of FT and TFL1 have remained mysterious. Recent studies in multiple species have unveiled diverse roles of the FT/TFL 1 gene family in developmental processes other than flowering regulation. In addition, the striking evolution of FT homologs into flowering repressors has occurred independently in several species during the evolution of flowering plants. These reports indicate that the FT/TFL1 gene family is a major target of evolution in nature. Here, we comprehen- sively survey the conserved and diverse functions of the FTITFL1 gene family throughout the plant kingdom, summarize new findings regarding the unique evolution of FT in multiple species, and highlight recent work elucidating the molecular mechanisms of these proteins.

关键词： FT TFL1 pEBp flowering evolution inflorescence architecture

The Arabidopsis Ap2/ERF Transcription Factor RAp2.11 Modulates plant Response to Low-potassium Conditions

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Molecular plant 2012年第5期5卷 1042-1057页

作者： Min Jung Kim daniel Ruzicka Ryoung Shin daniel p. Schachtman Donald Danforth plant Science Center St Louis MO 63132 USA RIKEN plant Science Center Yokohama Kanagawa 230-0045 Japan present address:Monsanto Company 700 Chesterfield Parkway Chesterfield MO 63017 USA

plants respond to low-nutrient conditions through metabolic and morphology changes that increase their ability to survive and grow. The transcription factor RAp2.11 was identified as a component in the response to low potassium through regulation of the high-affinity K＋ uptake transporter AtHAK5 and other components of the low- potassium signal transduction pathway. RAp2.11 was identified through the activation tagging of Arabidopsis lines that contained a luciferase marker driven by the AtHAK5 promoter that is normally only induced by low potassium. This factor bound to a GCC-box of the AtHAK5 promoter in vitro and in vivo. Transcript profiling revealed that a large number of genes were up-regulated in roots by RAp2.11 overexpression. Many regulated genes were identified to be in functional cate- gories that are important in Iow-K＋ signaling. These categories included ethylene signaling, reactive oxygen species pro- duction, and calcium signaling. promoter regions of the up-regulated genes were enriched in the GCCGGC motif also contained in the AtHAK5 promoter. These results suggest that RAp2.11 regulates AtHAK5 expression under Iow-K＋ con- ditions and also contributes to a coordinated response to low-potassium conditions through the regulation of other genes in the Iow-K＋ signaling cascade.

关键词： potassium deprivation transport transcription factor nutrient sensing signal transduction.

The COVID-19 pandemic and Elimination of Tuberculosis in China

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China CDC weekly 2021年第12期3卷 260-264页

作者： daniel p.Chin Global Health programBill&Melinda Gates Foundation

One of the best kept secrets in global public health ishow China achieved the tuberculosis(TB)targets inthe United Nation’s Millennium Development Goals(MDG).The MDG’s TB targets were to reduce theprevalence and mortality of TB by 50%between 1990and *** 2010,China had reduced its TBprevalence and mortality by 65%and 80%,(1−2)which meant China exceeded the MDG targets 5 yearsbefore the MDG deadline.

关键词： mortality prevalence tuberculosis

Morphological stability of three-dimensional cementite rods in polycrystalline system:A phase-field analysis

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Journal of Materials Science & Technology 2021年第18期77卷 252-268页

作者： Tobias Mittnacht p.G.Kubendran Amos daniel Schneider Britta Nestler Institute of Applied Materials(IAM-CMS) Karlsruhe Institute of Technology(KIT)Strasse am Forum 776131 KarlsruheGermany Institute of Digital Materials Science(IDM) Karlsruhe University of Applied SciencesMoltkestr.3076133 KarlsruheGermany Department of Metallurgical and Materials Engineering National Institute of TechnologyTiruchirappalli-620015Tamil NaduIndia

Transformations accompanying shape-instability govern the morphological configuration and distribution of the phases in a *** to the influence of the microstructure on the properties of a material,in the present work,the stability of three-dimensional rods in a‘representative'polycrystalline system is extensively analysed.A multiphase-field model,which recovers the physical laws and sharpinterface relations,and includes grain boundary diffusion,is adopted to investigate the morphological evolution of the ***,the efficiency of the numerical approach is ensured by establishing the volume-preserving chemical equilibrium through the incorporation TCFe8(CALpHAD)data and solving phase-field evolution in the Allen-Cahn *** morphological evolution of the rod in the representative multiphase system exhibits a unique transformation mechanism which is significantly different from the evolution of an isolated *** is realised that,in a polycrystalline arrangement,irrespective of the initial size of the rod,the shape-change begins with the energy-minimising events at the triple *** early transformation renders a characteristic morphology at the longitudinal ends of the structure,which introduces sufficient driving-force through the curvature-difference for the subsequent morphological *** continued mass transfer to the terminations,ultimately,breaks-off the rod into separate entities that are entangled in the grain *** increase in the aspect ratio of the rod,it is identified that the source of mass transfer,which turns into the ovulation site,shifts from the *** increases the number of fragmentation events and introduces satellite *** size of the satellite particle is dictated by a definite ovulation criterion,which is ascertained by examining the transformation of different-sized rods.A comprehensive understanding of the transformation kinetics and mechanism governing the mo

关键词： Shape instability pearlite spheroidization Sub-critical annealing phase-field simulations

A peroxidase Contributes to ROS production during Arabidopsis Root Response to potassium Deficiency

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Molecular plant 2010年第2期3卷 420-427页

作者： Min Jung Kim Silvano Ciani daniel p. Schachtman Donald Danforth plant Science Center 975 North Warson Road St Louis MO 63132 USA present address: Department of Biology Washington University in St Louis St Louis MO 63130 USA present address: Monsanto Company St Louis MO 63017 USA

Reactive oxygen species （ROS） play an important role in root responses to potassium deprivation by regulating the expression of the high-affinity K＋ transporter gene AtHAK5 and other genes. Activation-tagged lines of Arabidopsis plants containing the AtHAK5 promoter driving luciferase were screened for bioluminescence under potassium- sufficient conditions. A member of the type Ill peroxidase family, RCI3, was isolated and when it was overexpressed by the activation tag, this led to the enhanced expression of luciferase and the endogenous AtHAKS. RCI3 was found to be up- regulated upon potassium deprivation. plants overexpressing RCI3 （RCI3-ox） showed more ROS production and AtHAK5 expression whereas the ROS production and AtHAK5 expression were reduced in rci3-1 under K＋-deprived conditions. These results suggested that RCI3 is involved in the production of ROS under potassium deprivation and that RCI3- mediated ROS production affects the regulation of AtHAK5 expression. This peroxidase appears to be another component of the low-potassium signal transduction pathway in Arabidopsis roots.

关键词： Abiotic/environmental stress nutrition signal transduction Arabidopsis ROS production peroxidase.

Improving Energy Market Regulation:Domestic and International Issues

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Economic and political Studies 2013年第1期1卷 21-43页

作者： daniel p.AHN Citigroup and Columbia University

Recent extreme energy price highs and volatility have brought worldwide attention to the regulation of commodity markets in the context of the broader global financial *** part of the DoddFrank Act,the *** now mandates centralized clearing and margin and capital *** commodity markets are globally integrated and international policy coordination is required for effective market *** regulation and supervision of commodity markets has been highlighted in the G20 *** details of the new global regulatory landscape still need to be fleshed out,particularly in five major areas:physical transparency;financial transparency;centralized clearing and standardized contracts;capital and margin requirements;and position *** paper presents energy policy options that achieve market efficiency by preventing market manipulation,manage systemic risk,and control excessive volatility.

关键词： oil prices speculation financial regulation centralized clearing transparency

A systematic review of running-related musculoskeletal injuries in runners

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Journal of Sport and Health Science 2021年第5期10卷 513-522页

作者： Nicolas Kakouris Numan Yener daniel T.p.Fong National Centre for Sport and Exercise Medicine School of SportExercise and Health SciencesLoughborough UniversityLoughboroughLE113TUUK

Objective:Running-related musculoskeletal injuries(RRMIs),especially stemming from overuse,frequently occur in *** study aimed to systematically review the literature and determine the incidence and prevalence proportion of RRMIs by anatomic location and specific ***:An electronic database search with no date beginning restrictions was performed in SpORTDiscus,pubMed,and MEDLINE up to June *** studies were used to find the anatomic location and the incidence proportion of each RRMI,whereas retrospective or cross-sectional studies were used to find the prevalence proportion of each RRMI.A separate analysis for ultramarathon runners was ***:The overall injury incidence and prevalence were 40.2%±18.8%and 44.6%±18.4%(mean±SD),*** knee,ankle,and lower leg accounted for the highest proportion of injury incidence,whereas the knee,lower leg,and foot/toes had the highest proportion of injury *** tendinopathy(10.3%),medial tibial stress syndrome(9.4%),patellofemoral pain syndrome(6.3%),plantar fasciitis(6.1%),and ankle sprains(5.8%)accounted for the highest proportion of injury incidence,whereas patellofemoral pain syndrome(16.7%),medial tibial stress syndrome(9.1%),plantar fasciitis(7.9%),iliotibial band syndrome(7.9%),and Achilles tendinopathy(6.6%)had the highest proportion of injury *** ankle(34.5%),knee(28.1%),and lower leg(12.9%)were the 3 most frequently injured sites among ***:The injury incidence proportions by anatomic location between ultramarathoners and non-ultramarathoners were not significantly different(p=0.798).The pathologies with the highest incidence proportion of injuries were anterior compartment tendinopathy(19.4%),patellofemoral pain syndrome(15.8%),and Achilles tendinopathy(13.7%).The interpretation of epidemiological data in RRMIs is limited due to several methodological issues encountered.

关键词： Epidemiology Injury Injury prevention Rehabilitation Running