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Nanog and transcriptional networks in embryonic stem cell pluripotency

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Cell Research 2007年第1期17卷 42-49页

作者： james A Thomson PO Box 7365 WiCell Research Institute WI53715-1299 W153706-1509 1220 Capitol Court USAThe Genome Center of Wisconsin WI 53707-7365 425 Henry Mall The Wisconsin National Primate Research Center University of Wisconsin-Madison The Department of Anatomy WI 53706 470 N.Charter Street University of Wisconsin-Madison Medical School

Several extrinsic signals such as LIF,BMP and Wnt can support the self-renewal and pluripotency of embryonic stem(ES) cells through regulating the"pluripotent genes." A unique homeobox transcription factor,Nanog,is one of the keydownstream effectors of these *** level of Nanog can maintain the mouse ES cell self-renewal indepen-dent of LIF and enable human ES cell growth without feeder *** addition to the external signal pathways,intrinsictranscription factors such as FoxD3,P53 and Oct4 are also involved in regulating the expression of ***,Nanog works together with other key pluripotent factors such as Oct4 and Sox2 to control a set of target genes that haveimportant functions in ES cell *** key factors form a regulatory network to support or limit each other’sexpression level,which maintains the properties of ES cells.

关键词： Nanog embryonic stem cell pluripotency transcription factor

On the homotopy category of AC-injective complexes

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Frontiers of Mathematics in China 2017年第1期12卷 97-115页

作者： james GILLESPIE Ramapo College of New Jersey School of Theoretical and Applied Science Mahwah NJ 07430 USA

Let R be any ring. We motivate the study of a class of chain complexes of injective R-modules that we call A C-injective complexes, showing that K（AC-Inj）, the chain homotopy category of all AC-injective complexes, is always a compactly generated triangulated category. In general, all DG- injective complexes are AC-injective and in fact there is a recollement linking K（AC-Inj） to the usual derived category D（R）. This is based on the author＇s recent work inspired by work of Krause and Stovicek. Our focus here is on giving straightforward proofs that our categories are compactly generated.

关键词： AC-injective recollement compactly generated triangulated category

IMPACT OF URBANIZATION ON STRUCTURE AND FUNCTION OF RIVER SYSTEM—Case Study of Shanghai,China

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Chinese Geographical Science 2006年第2期16卷 102-108页

作者： Philip james Research Institute for the Built and Human Environment School of Environment and Life Sciences University of Salford Greater Manchester M5 4WT UK

Urbanization can affect the physical process of river growth, modify stream structure and further influence the functions of river system. Shanghai is one of the largest cities in the world, which is located in Changjiang (Yangtze) River Delta in China. Since the 1970s, the whole river system in Shanghai has been planned and managed by the Shanghai Water Authority. The primary management objectives in the last 30 years have been to enhance irrigation and flood-control. By using Horton-Strahler classification and Horton laws as a reference, a novel method of stream classification, in conjunction with the traditional and specially designed indicators, was applied to understanding the structure and functions of the river system in Shanghai. Correlation analysis was used to identify the interrelations among indicators. It was found that the impact of urbanization on the river system was significant although natural laws and physical characteristics marked a super-developed river system. There was an obvious correlation between the degree of urbanization and the abnormal values of some indicators. Urbanization impacts on river system such as branches engineered out, riverbank concreting and low diversity of river style were widely observed. Each indicator had distinct sensibility to urbanization so they could be used to describe different characteristics of urban river system. The function indicators were significantly related to structure indicators. Stream structure, described by fractal dimension and complexity of river system, was as important as water area ratio for maintaining river’s multi-function.

关键词： river system stream classification Horton law urbanization Shanghai

ON INTEGRATION AND ADAPTATION IN COMPLEX SERVICE SYSTEMS

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 385-415页

作者： james M.TIEN College of Engineering University of Miami Coral GablesFloridaUSA

The services sector employs a large and growing proportion of workers in the industrialized nations, and it is increasingly dependent on information and communication technologies. While the interdependences, similarities and complementarities of manufacturing and services are significant, there are considerable differences between goods and services, including the shift in focus from mass production to mass customization （whereby a service is produced and delivered in response to a customer＇s stated or imputed needs）. In general, services can be considered to be knowledge-intensive agents or components which work together as providers and consumers to create or co-produce value. Like manufacturing systems, an efficient service system must be an integrated system of systems, leading to greater connectivity and interdependence. Integration must occur over the physical, temporal, organizational and functional dimensions, and must include methods concerned with the component, the management, and the system. Moreover, an effective service system must also be an adaptable system, leading to greater value and responsiveness. Adaptation must occur over the dimensions of monitoring, feedback, cybernetics and learning, and must include methods concerned with space, time, and system. In sum, service systems are indeed complex, especially due to the uncertainties associated with the human-centered aspects of such systems. Moreover, the system complexities can only be dealt with methods that enhance system integration and adaptation. The paper concludes with several insights, including a plea to shift the current misplaced focus on developing a science or discipline for services to further developing a systems engineering approach to services, an approach based on the integration and adaptation of a host of sciences or disciplines （e.g., physics, mathematics, statistics, psychology, sociology, etc.）. In fact, what is required is a services-related transdisciplinary - beyond a s

关键词： Services service system system components system integration system adaptation system of systems decision informatics real-time decision making

BIG DATA:UNLEASHING INFORMATION

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Journal of Systems Science and Systems Engineering 2013年第2期22卷 127-151页

作者： james M.TIEN College of Engineering University of Miami

At present, it is projected that about 4 zettabytes （or 10^＊＊21 bytes） of digital data are being generated per year by everything from underground physics experiments to retail transactions to security cameras to global positioning systems. In the U. S., major research programs are being funded to deal with big data in all five sectors （i.e., services, manufacturing, construction, agriculture and mining） of the economy. Big Data is a term applied to data sets whose size is beyond the ability of available tools to undertake their acquisition, access, analytics and/or application in a reasonable amount of time. Whereas Tien （2003） forewarned about the data rich, information poor （DRIP） problems that have been pervasive since the advent of large-scale data collections or warehouses, the DRIP conundrum has been somewhat mitigated by the Big Data approach which has unleashed information in a manner that can support informed - yet, not necessarily defensible or valid - decisions or choices. Thus, by somewhat overcoming data quality issues with data quantity, data access restrictions with on-demand cloud computing, causative analysis with correlative data analytics, and model-driven with evidence-driven applications, appropriate actions can be undertaken with the obtained information. New acquisition, access, analytics and application technologies are being developed to further Big Data as it is being employed to help resolve the 14 grand challenges （identified by the National Academy of Engineering in 2008）, underpin the 10 breakthrough technologies （compiled by the Massachusetts Institute of Technology in 2013） and support the Third Industrial Revolution of mass customization.

关键词： Big data data acquisition data access data analytics data application decision informatics products processes adaptive services digital manufacturing mass customization third industrial revolution

Astaxanthin Accumulation in the Green Alga Haematococcus pluvialis： Effects of Cultivation Parameters

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Journal of Integrative Plant Biology 2007年第4期49卷 447-451页

作者： Ping He james Duncan james Barber Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Division of Molecular Biosciences Imperial College London London SW7 2AY UK Graduate School of Beijing Forestry University Beijing 100083 China

The green alga, Haematococcus pluvlalis Flotow is used as a source of the ketocarotenoid astaxanthin for application in fish aquaculture, pharmaceutical and cosmetic industries. Ceils of the green alga were induced by the application of different light and starvation conditions to evaluate the effect in astaxanthin accumulate. The conditions used for the Induction were high light intensity （170 μmol·m^-2·s^-1）, iron starvation, sulfur starvation and phosphate starvation. The results show that stresses applied in culture, which interfere with cell division, trigger the accumulation of astaxanthin. Notably, sulfur starvation results in a massive accumulation of this commercially important carotenoid.

关键词： astaxanthin Haematococcus pluvialis iron light phosphate stress sulfur.

Phylogenetic reconstruction of Chirita and allies (Gesneriaceae) with taxonomic treatments

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Journal of Systematics and Evolution 2011年第1期49卷 50-64页

作者： james F. SMITH Department of Biological Sciences Boise State University

Chirita D. Don, a large genus in the subfamily Cyrtandroideae of Gesneriaceae, has been the subject of much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-F for molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artificial, polyphyletic genus. The most important character that defines Chirita, the dorso-ventrally oblique and bilamellar stigma, has evolved convergently in different clades of diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of Chirita. The species of Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea form a monophyletic group that is sister to a strongly supported clade comprising four monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We further analyzed the morphological evolution of Chirita and identified a series of morphological synapomorphies for the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.

关键词： Chirita D. Don morphological evolution phylogenetic reconstruction polyphyly taxonomic treatment.

THE SPUTNIK OF SERVGOODS： AUTONOMOUS VEHICLES

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Journal of Systems Science and Systems Engineering 2017年第2期26卷 133-162页

作者： james M. Tien College of Engineering University of Miami Coral Gables Florida 33146 USA

In an earlier paper （Tien 2015）, the author defmed the concept of a servgood, which can be thought of as a physical good or product enveloped by a services-oriented layer that makes the good smarter or more adaptable and customizable for a particular use. Adding another layer of physical sensors could then enhance its smartness and intelligence, especially if it were to be connected with each other or with other servgoods through the Internet of Things. Such sensed servgoods are becoming the products of the future. Indeed, autonomous vehicles can be considered the exemplar servgoods of the future; it is about decision informatics and embraces the advanced technologies of sensing （i.e., Big Data）, processing （i.e., real-time analytics）, reacting （i.e., real-time decision-making）, and learning （i.e., deep learning）. Since autonomous vehicles constitute a huge quality-of-life disruption, it is also critical to consider its policy impact on privacy and security, regulations and standards, and liability and insurance. Finally, just as the Soviet Union inaugurated the space age on October 4, 1957, with the launch of Sputnik, the first man-made object to orbit the Earth, the U. S. has inaugurated an age of automata or autonomous vehicles that can be considered to be the U. S. Sputnik of servgoods, with the full support of the U. S. government, the U. S. auto industry, the U. S. electronic industry, and the U.S. higher educational enterprise.

关键词： Autonomous vehicles goods services servgoods sensors Internet of Things decisioninformatics Big Data real-time analytics cloud computing deep learning privacy security regulations,standards liability insurance Sputnik

Seasonal movement of the American horseshoe crab Limulus polyphemus in a semi-enclosed bay on Cape Cod,Massachusetts (USA) as determined by acoustic telemetry

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Current Zoology 2010年第5期56卷 575-586页

作者： Mary-Jane james-PIRRI Graduate School of Oceanography University of Rhode Island

American horseshoe crabs Limulus polyphemus were tracked using acoustic telemetry and traditional tagging in a semi-enclosed bay on Cape Cod （Pleasant Bay）, Massachusetts, USA, to determine seasonal movement patterns. Fifty-five actively spawning females were fitted with transmitters in 2008 and 2009 and were tracked using acoustic telemetry from May 2008 through July 2010. Fil^een crabs with transmitters also had archive depth-temperature tags attached. In addition, over 2000 spawning crabs （males and females） were tagged with US Fish and Wildlife CIdSFWS） button tags over the same period. Ninety-one percent of the crabs with transmitters were detected during this study. In the spring, crabs were primarily located in the northern section of the bay near spawning beaches, whereas in the fall crabs moved towards the deeper portions of the bay, and some may have overwIntered in the bay. There was evidence that a majority （58%-71%） of the females with transmitters spawned in two sequential seasons. One archive tag was recovered resulting in a year-long continuous record of depth and tem- perature data that, when integrated with telemetry data, indicated that the crab overwintered in the bay. The live recapture rate of crabs with USFWS button tags was 11%, with all re-sighted crabs except one observed inside Pleasant Bay. Eighty-three percent of recaptures were found within 2.5kin of the tagging location, and 51% were observed at the same beach where they were tagged. This study provides further evidence that horseshoe crabs in Pleasant Bay may be philopatric to this embayment

关键词： Horseshoe crab New England Telemetry Seasonal movement