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Ecological theatre and the evolutionary game: how environmental and demographic factors determine payoffs in evolutionary games
In the standard approach to evolutionary games and replicator dynamics, differences in fitness can be interpreted as an excess from the mean Malthusian growth rate in the population. In the underlying reasoning, related to an analysis of "costs" and "benefits", there is a silent assumption that fitness can be described in some type of units. However, in most cases these units of measure are not explicitly specified. Then the question arises: are these theories testable? How can we measure "benefit" or "cost"? A natural language, useful for describing and justifying comparisons of strategic "cost" versus "benefits", is the terminology of demography, because the basic events that shape the outcome of natural selection are births and deaths. In this paper, we present the consequences of an explicit analysis of births and deaths in an evolutionary game theoretic framework. We will investigate different types of mortality pressures, their combinations and the possibility of trade-offs between mortality and fertility. We will show that within this new approach it is possible to model how strictly ecological factors such as density dependence and additive background fitness, which seem neutral in classical theory, can affect the outcomes of the game. We consider the example of the Hawk-Dove game, and show that when reformulated in terms of our new approach new details and new biological predictions are produced
Be[com]ing a Teacher in Neoliberal Times: Visioning as Resistance in Teacher Education
Teacher education is under assault from the corporatization of public education. There is evidence that reductive, essentialized/ing discourses of standardization and compliance exert intense pressures on teacher education, and a market-based, audit culture constricts conceptions of the “good teacher”. Despite the pervasiveness of neoliberal discourses, little is known about how student teachers experience increased corporatization in education, or about how they act rather than are acted upon in this context. In examining these dynamics, we explore the following research questions: (a) How do student teachers make sense of neoliberal discourses in teaching? (b) How do student teachers experience the process of what Hammerness describes as “teacher visioning” in the context of neoliberal discourses? (c) What, if any, effect does visioning have on their responses to these discourses? We draw on qualitative data including focus groups, interviews, and document analysis from a group of early childhood student teachers enrolled in a public teacher education program and placed in field sites around eastern Massachusetts. Based on our findings, we argue that teacher visioning can, under certain circumstances, serve as an impetus for student teacher resistance to neoliberal pressures
Stochastic population growth in spatially heterogeneous environments
Classical ecological theory predicts that environmental stochasticity
increases extinction risk by reducing the average per-capita growth rate of
populations. To understand the interactive effects of environmental
stochasticity, spatial heterogeneity, and dispersal on population growth, we
study the following model for population abundances in patches: the
conditional law of given is such that when is small the
conditional mean of is approximately , where and are the abundance and per
capita growth rate in the -th patch respectivly, and is the
dispersal rate from the -th to the -th patch, and the conditional
covariance of and is approximately . We show for such a spatially extended population that if
is the total population abundance, then ,
the vector of patch proportions, converges in law to a random vector
as , and the stochastic growth rate equals the space-time average per-capita growth rate
\sum_i\mu_i\E[Y_\infty^i] experienced by the population minus half of the
space-time average temporal variation \E[\sum_{i,j}\sigma_{ij}Y_\infty^i
Y_\infty^j] experienced by the population. We derive analytic results for the
law of , find which choice of the dispersal mechanism produces an
optimal stochastic growth rate for a freely dispersing population, and
investigate the effect on the stochastic growth rate of constraints on
dispersal rates. Our results provide fundamental insights into "ideal free"
movement in the face of uncertainty, the persistence of coupled sink
populations, the evolution of dispersal rates, and the single large or several
small (SLOSS) debate in conservation biology.Comment: 47 pages, 4 figure
Stress-induced glucocorticoid receptor activation determines functional recovery following ischemic stroke
Autoimmune Pancreatitis Exhibiting Multiple Mass Lesions
Our case is a first report of autoimmune pancreatitis with multiple masses within the pancreas which was pathologically diagnosed by endoscopic ultrasound-guided fine needle aspiration and treated by steroid. The masses disappeared by steroid therapy. Our case is informative to know that autoimmune pancreatitis sometimes exhibits multiple masses within the pancreas and to diagnose it without unnecessary surgery
Low Temperature-Dependent Salmonid Alphavirus Glycoprotein Processing and Recombinant Virus-Like Particle Formation
Pancreas disease (PD) and sleeping disease (SD) are important viral scourges in aquaculture of Atlantic salmon and rainbow trout. The etiological agent of PD and SD is salmonid alphavirus (SAV), an unusual member of the Togaviridae (genus Alphavirus). SAV replicates at lower temperatures in fish. Outbreaks of SAV are associated with large economic losses of ∼17 to 50 million $/year. Current control strategies rely on vaccination with inactivated virus formulations that are cumbersome to obtain and have intrinsic safety risks. In this research we were able to obtain non-infectious virus-like particles (VLPs) of SAV via expression of recombinant baculoviruses encoding SAV capsid protein and two major immunodominant viral glycoproteins, E1 and E2 in Spodoptera frugiperda Sf9 insect cells. However, this was only achieved when a temperature shift from 27°C to lower temperatures was applied. At 27°C, precursor E2 (PE2) was misfolded and not processed by host furin into mature E2. Hence, E2 was detected neither on the surface of infected cells nor as VLPs in the culture fluid. However, when temperatures during protein expression were lowered, PE2 was processed into mature E2 in a temperature-dependent manner and VLPs were abundantly produced. So, temperature shift-down during synthesis is a prerequisite for correct SAV glycoprotein processing and recombinant VLP production
Misuse of "study drugs:" prevalence, consequences, and implications for policy
BACKGROUND: Non-medical/illegal use of prescription stimulants popularly have been referred to as "study drugs". This paper discusses the current prevalence and consequences of misuse of these drugs and implications of this information for drug policy. RESULTS: Study drugs are being misused annually by approximately 4% of older teens and emerging adults. Yet, there are numerous consequences of misuse of prescription stimulants including addiction, negative reactions to high dosages, and medical complications. Policy implications include continuing to limit access to study drugs, finding more safe prescription drug alternatives, interdiction, and public education. CONCLUSION: Much more work is needed on prescription stimulant misuse assessment, identifying the extent of the social and economic costs of misuse, monitoring and reducing access, and developing prevention and cessation education efforts
Characterization of Serum Proteins Associated with IL28B Genotype among Patients with Chronic Hepatitis C
Introduction: Polymorphisms near the IL28B gene (e.g. rs12979860) encoding interferon lambda 3 have recently been associated with both spontaneous clearance and treatment response to pegIFN/RBV in chronic hepatitis C (CHC) patients. The molecular consequences of this genetic variation are unknown. To gain further insight into IL28B function we assessed the association of rs12979860 with expression of protein quantitative traits (pQTL analysis) generated using open-platform proteomics in serum from patients
The Brustkrebs-Studien.de website for breast cancer patients: User acceptance of a German internet portal offering information on the disease and treatment options, and a clinical trials matching service
<p>Abstract</p> <p>Background</p> <p>The internet portal <url>http://www.brustkrebs-studien.de</url> (BKS) was launched in 2000 by the German Society of Senology (DGS) and the Baden-Württemberg Institute for Women's Health (IFG) to provide expert-written information on breast cancer online and to encourage and facilitate the participation of breast cancer patients in clinical trials. We describe the development of BKS and its applications, and report on website statistics and user acceptance.</p> <p>Methods</p> <p>Existing registries, including ClinicalTrials.gov, were analysed before we designed BKS, which combines a trial registry, a knowledge portal, and an online second opinion service. An advisory board guided the process. Log files and patient enquiries for trial participation and second opinions were analysed. A two-week user satisfaction survey was conducted online.</p> <p>Results</p> <p>During 10/2005-06/2010, the portal attracted 702,655 visitors, generating 15,507,454 page views. By 06/2010, the website's active scientific community consisted of 189 investigators and physicians, and the registry covered 163 clinical trial protocols. In 2009, 143 patients requested trial enrolment and 119 sought second opinions or individual treatment advice from the expert panel. During the two-week survey in 2008, 5,702 BKS visitors submitted 507 evaluable questionnaires. Portal acceptance was high. Respondents trusted information correctness (80%), welcomed self-matching to clinical trials (79%) and planned to use the portal in the future (76%) and recommend it to others (81%).</p> <p>Conclusions</p> <p>BKS is an established and trusted breast cancer information platform offering up-to-date resources and protocols to the growing physician and patient community to encourage participation in clinical trials. Further studies are needed to assess potential increases in trial enrolment by eligibility matching services.</p
Measured and Simulated Nitrous Oxide Emissions from Ryegrass- and Ryegrass/White Clover-Based Grasslands in a Moist Temperate Climate
There is uncertainty about the potential reduction of soil nitrous oxide (N2O) emission when fertilizer nitrogen (FN) is partially or completely replaced by biological N fixation (BNF) in temperate grassland. The objectives of this study were to 1) investigate the changes in N2O emissions when BNF is used to replace FN in permanent grassland, and 2) evaluate the applicability of the process-based model DNDC to simulate N2O emissions from Irish grasslands. Three grazing treatments were: (i) ryegrass (Lolium perenne) grasslands receiving 226 kg FN ha−1 yr−1 (GG+FN), (ii) ryegrass/white clover (Trifolium repens) grasslands receiving 58 kg FN ha−1 yr−1 (GWC+FN) applied in spring, and (iii) ryegrass/white clover grasslands receiving no FN (GWC-FN). Two background treatments, un-grazed swards with ryegrass only (G–B) or ryegrass/white clover (WC–B), did not receive slurry or FN and the herbage was harvested by mowing. There was no significant difference in annual N2O emissions between G–B (2.38±0.12 kg N ha−1 yr−1 (mean±SE)) and WC-B (2.45±0.85 kg N ha−1 yr−1), indicating that N2O emission due to BNF itself and clover residual decomposition from permanent ryegrass/clover grassland was negligible. N2O emissions were 7.82±1.67, 6.35±1.14 and 6.54±1.70 kg N ha−1 yr−1, respectively, from GG+FN, GWC+FN and GWC-FN. N2O fluxes simulated by DNDC agreed well with the measured values with significant correlation between simulated and measured daily fluxes for the three grazing treatments, but the simulation did not agree very well for the background treatments. DNDC overestimated annual emission by 61% for GG+FN, and underestimated by 45% for GWC-FN, but simulated very well for GWC+FN. Both the measured and simulated results supported that there was a clear reduction of N2O emissions when FN was replaced by BNF
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