2,021 research outputs found
Research and development of high-performance light-weight fuel cell electrodes final report, nov. 1, 1963 - oct. 31, 1964
High performance light weight fuel cell electrode developmen
The resistance of randomly grown trees
Copyright @ 2011 IOP Publishing Ltd. This is a preprint version of the published article which can be accessed from the link below.An electrical network with the structure of a random tree is considered: starting from a root vertex, in one iteration each leaf (a vertex with zero or one adjacent edges) of the tree is extended by either a single edge with probability p or two edges with probability 1 â p. With each edge having a resistance equal to 1 omega, the total resistance Rn between the root vertex and a busbar connecting all the vertices at the nth level is considered. A dynamical system is presented which approximates Rn, it is shown that the mean value (Rn) for this system approaches (1 + p)/(1 â p) as n â â, the distribution of Rn at large n is also examined. Additionally, a random sequence construction akin to a random Fibonacci sequence is used to approximate Rn; this sequence is shown to be related to the Legendre polynomials and its mean is shown to converge with |(Rn) â (1 + p)/(1 â p)| âź nâ1/2.Engineering and Physical Sciences Research Council (EPSRC
Comportamento de genĂłtipos de milho safrinha em duas ĂŠpocas de semeadura em Dourados, MS.
bitstream/item/65362/1/29896.pdfOrganizado por Gessi Ceccon e Luiz Alberto Staut
Analysis of United Kingdom Off-Highway Construction Machinery Market and Its Consumers Using New-Sales Data
The off-highway construction machinery market and its consumers have attracted minimal previous research. This study addresses that void by analyzing annual United Kingdom (UK) (volume/portfolio) new-sales data for the 10 most popular products within that market, 1990â2010 inclusive. Graphical, descriptive statistical, Pearson-correlational, autocorrelational, and elementary modeling are employed to identify contrasts in sales regarding (1) high- and low-volume items; (2) growth trends and significant recessionary effects on volumes; (3) a demand change point circa 1997, since when annual product portfolio has changed little; and (4) product associations in consumer demand. Significant association is demonstrated between demand and construction output, especially with the value of new housing. Subsequently, consumption of wheeled loaders is modeled using construction volume, and demand for mini and crawler excavators is modeled using new-housing data. Time series trends for these machinery types are presented and forecast through 2015. The primary contribution of this study is a deeper understanding of the UK new-machinery market and the predilections of its consumers over the last two decades (to present)
Degradation of human kininogens with the release of kinin peptides by extracellular proteinases of Candida spp.
The secretion of proteolytic enzymes by pathogenic microorganisms is one of the most successful strategies used by pathogens to colonize and infect the host organism. The extracellular microbial proteinases can seriously deregulate the homeostatic proteolytic cascades of the host, including the kinin-forming system, repeatedly reported to he activated during bacterial infection. The current study assigns a kinin-releasing activity to secreted proteinases of Candida spp. yeasts, the major fungal pathogens of humans. Of several Candida species studied, C. parapsilosis and C. albicans in their invasive filamentous forms are shown to produce proteinases which most effectively degrade proteinaceous kinin precursors, the kininogens. These enzymes, classified as aspartyl proteinases, have the highest kininogen-degrading activity at low pH (approx. 3.5), but the associated production of bradykinin-related peptides from a small fraction of kininogen molecules is optimal at neutral pH (6.5). The peptides effectively interact with cellular B2-type kinin receptors. Moreover, kinin-related peptides capable of interacting with inflammation-induced B1-type receptors are also formed, but with a reversed pH dependence. The presented variability of the potential extracellular kinin production by secreted aspartyl proteinases of Candida spp. is consistent with the known adaptability of these opportunistic pathogens to different niches in the host organism
The soil and plant biogeochemistry sampling design for The National Ecological Observatory Network
Human impacts on biogeochemical cycles are evident around the world, from changes to forest structure and function due to atmospheric deposition, to eutrophication of surface waters from agricultural effluent, and increasing concentrations of carbon dioxide (CO2) in the atmosphere. The National Ecological Observatory Network (NEON) will contribute to understanding human effects on biogeochemical cycles from local to continental scales. The broad NEON biogeochemistry measurement design focuses on measuring atmospheric deposition of reactive mineral compounds and CO2 fluxes, ecosystem carbon (C) and nutrient stocks, and surface water chemistry across 20 ecoâclimatic domains within the United States for 30 yr. Herein, we present the rationale and plan for the groundâbased measurements of C and nutrients in soils and plants based on overarching or âhighâlevelâ requirements agreed upon by the National Science Foundation and NEON. The resulting design incorporates early recommendations by expert review teams, as well as recent input from the larger natural sciences community that went into the formation and interpretation of the requirements, respectively. NEON\u27s efforts will focus on a suite of data streams that will enable endâusers to study and predict changes to biogeochemical cycling and transfers within and across air, land, and water systems at regional to continental scales. At each NEON site, there will be an initial, oneâtime effort to survey soil properties to 1 m (including soil texture, bulk density, pH, baseline chemistry) and vegetation community structure and diversity. A sampling program will follow, focused on capturing longâterm trends in soil C, nitrogen (N), and sulfur stocks, isotopic composition (of C and N), soil N transformation rates, phosphorus pools, and plant tissue chemistry and isotopic composition (of C and N). To this end, NEON will conduct extensive measurements of soils and plants within stratified random plots distributed across each site. The resulting data will be a new resource for members of the scientific community interested in addressing questions about longâterm changes in continentalâscale biogeochemical cycles, and is predicted to inspire further processâbased research
Weight Gain in Early Life Predicts Risk of Islet Autoimmunity in Children With a First-Degree Relative With Type 1 Diabetes
OBJECTIVEâIn a prospective birth cohort study, we followed infants who had a first-degree relative with type 1 diabetes to investigate the relationship between early growth and infant feeding and the risk of islet autoimmunity
Phase transitions and volunteering in spatial public goods games
Cooperative behavior among unrelated individuals in human and animal
societies represents a most intriguing puzzle to scientists in various
disciplines. Here we present a simple yet effective mechanism promoting
cooperation under full anonymity by allowing for voluntary participation in
public goods games. This natural extension leads to rock--scissors--paper type
cyclic dominance of the three strategies cooperate, defect and loner i.e. those
unwilling to participate in the public enterprise. In spatial settings with
players arranged on a regular lattice this results in interesting dynamical
properties and intriguing spatio-temporal patterns. In particular, variations
of the value of the public good leads to transitions between one-, two- and
three-strategy states which are either in the class of directed percolation or
show interesting analogies to Ising-type models. Although volunteering is
incapable of stabilizing cooperation, it efficiently prevents successful
spreading of selfish behavior and enables cooperators to persist at substantial
levels.Comment: 4 pages, 5 figure
Travelling and sticky affects: : Exploring teens and sexualized cyberbullying through a Butlerian-Deleuzian- Guattarian lens
In this paper we combine the thinking of Deleuze and Guattari (1984, 1987) with Judith Butlerâs (1990, 1993, 2004, 2009) work to follow the rhizomatic becomings of young peopleâs affective relations in a range of on- and off-line school spaces. In particular we explore how events that may be designated as sexual cyberbullying are constituted and how they are mediated by technology (such as texting or in/through social networking sites). Drawing on findings from two different studies looking at teensâ uses of and experiences with social networking sites, Arto in Denmark, and Bebo in the UK, we use this approach to think about how affects flow, are distributed, and become fixed in assemblages. We map how affects are manoeuvred and potentially disrupted by young people, suggesting that in the incidences discussed affects travel as well as stick in points of fixation. We argue that we need to grasp both affective flow and fixity in order to gain knowledge of how subjectification of the gendered/classed/racialised/sexualised body emerges. A Butlerian-Deleuzian-Guattarian frame helps us to map some of these affective complexities that shape sexualized cyberbully events; and to recognize technologically mediated lines of flight when subjectifications are at least temporarily disrupted and new terms of recognition and intelligibility staked out. Keywords
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