1,585 research outputs found
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PTSD as meaning violation: Testing a cognitive worldview perspective
The cognitive perspective on posttraumatic stress disorder (PTSD) has been successful in explaining many PTSD-related phenomena and in developing effective treatments, yet some of its basic assumptions remain surprisingly underexamined. The present study tested 2 of these assumptions: (1) situational appraisals of the event as violating global meaning (i.e., beliefs and goals) is related to PTSD symptomatology, and (2) the effect of situational appraisals of violation on PTSD symptomatology is mediated by global meaning (i.e., views of self and world). We tested these assumptions in a cross-sectional study of 130 college students who had experienced a Diagnostic and Statistical Manual of Mental Disorders (4th ed., American Psychiatric Association, 1994) level trauma. Structural equation modeling showed that appraisals of the extent to which the trauma violated one's beliefs and goals related fairly strongly to PTSD. In addition, the effects of appraisals of belief and goal violations on PTSD symptoms were fully mediated through negative global beliefs about both the self and the world. These findings support the cognitive worldview perspective, highlighting the importance of the meaning individuals assign to traumatic events, particularly the role of meaning violation
Effects of Exogenous Yeast and Bacteria on the Microbial Population Dynamics and Outcomes of Olive Fermentations.
In this study, we examined Sicilian-style green olive fermentations upon the addition of Saccharomyces cerevisiae UCDFST 09-448 and/or Pichia kudriazevii UCDFST09-427 or the lactic acid bacteria (LAB) Lactobacillus plantarum AJ11R and Leuconostoc pseudomesenteroides BGM3R. Olives containing S. cerevisiae UCDFST 09-448, a strain able to hydrolyze pectin, but not P. kudriazevii UCDFST 09-427, a nonpectinolytic strain, exhibited excessive tissue damage within 4 weeks. DNA sequencing of fungal internal transcribed spacer (ITS) regions and comparisons to a yeast-specific ITS sequence database remarkably showed that neither S. cerevisiae UCDFST 09-448 nor P. kudriazevii UCDFST 09-427 resulted in significant changes to yeast species diversity. Instead, Candida boidinii constituted the majority (>90%) of the total yeast present, independent of whether S. cerevisiae or P. kudriazevii was added. By comparison, Lactobacillus species were enriched in olives inoculated with potential starter LAB L. plantarum AJ11R and L. pseudomesenteroides BGM3R according to community 16S rRNA gene sequence analysis. The bacterial diversity of those olives was significantly reduced and resembled control fermentations incubated for a longer period of time. Importantly, microbial populations were highly dynamic at the strain level, as indicated by the large variations in AJ11R and BGM3R cell numbers over time and reductions in the numbers of yeast isolates expressing polygalacturonase activity. These findings show the distinct effects of exogenous spoilage and starter microbes on indigenous communities in plant-based food fermentations that result in very different impacts on product quality. IMPORTANCE Food fermentations are subject to tremendous selective pressures resulting in the growth and persistence of a limited number of bacterial and fungal taxa. Although these foods are vulnerable to spoilage by unintended contamination of certain microorganisms, or alternatively, can be improved by the deliberate addition of starter culture microbes that accelerate or beneficially modify product outcomes, the impact of either of those microbial additions on community dynamics within the fermentations is not well understood at strain-specific or global scales. Herein, we show how exogenous spoilage yeast or starter lactic acid bacteria confer very different effects on microbial numbers and diversity in olive fermentations. Introduced microbes have long-lasting consequences and result in changes that are apparent even when levels of those inoculants and their major enzymatic activities decline. This work has direct implications for understanding bacterial and fungal invasions of microbial habitats resulting in pivotal changes to community structure and function
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Factor structure of the acute stress disorder scale in a sample of Hurricane Katrina evacuees
Acute stress disorder (ASD) is a poorly understood and controversial diagnosis (A. G. Harvey & R. A. Bryant, 2002). The present study used confirmatory factor analysis (CFA) to test the factor structure of the most widely used self-report measure of ASD, the Acute Stress Disorder Scale (R. A. Bryant, M. L. Moulds, & R. M. Guthrie, 2000), in a sample of Hurricane Katrina evacuees relocated to a Red Cross emergency shelter in Austin, Texas. Results indicated that the proposed 4-factor structure did not fit the data well. However, an alternate 2-factor model did fit the data well. This model included a second-order Distress factor (onto which the Reexperiencing, Arousal, and Avoidance factors loaded strongly) that was positively correlated with the Dissociation factor. Implications for the ASD construct and its measurement are discussed
Estimating Population Abundance with a Mixture of Physical Capture and PIT Tag Antenna Detection Data
The inclusion of passive interrogation antenna (PIA) detection data has promise to increase precision of population abundance estimates (Nˆ ). However, encounter probabilities are often higher for PIAs than for physical capture. If the difference is not accounted for, Nˆ may be biased. Using simulations, we estimated the magnitude of bias resulting from mixed capture and detection probabilities and evaluated potential solutions for removing the bias for closed capture models. Mixing physical capture and PIA detections (pdet) resulted in negative biases in Nˆ . However, using an individual covariate to model differences removed bias and improved precision. From a case study of fish making spawning migrations across a stream-wide PIA (pdet ≤ 0.9), the coefficient of variation (CV) of Nˆ declined 39%–82% when PIA data were included, and there was a dramatic reduction in time to detect a significant change in Nˆ . For a second case study, with modest pdet (≤0.2) using smaller PIAs, CV (Nˆ ) declined 4%–18%. Our method is applicable for estimating abundance for any situation where data are collected with methods having different capture–detection probabilities
Questioning the rise of gelatinous zooplankton in the World's oceans
During the past several decades, high numbers of gelatinous zooplankton species have been reported in many estuarine and coastal ecosystems. Coupled with media-driven public perception, a paradigm has evolved in which the global ocean ecosystems are thought to be heading toward being dominated by “nuisance” jellyfish. We question this current paradigm by presenting a broad overview of gelatinous zooplankton in a historicalcontext to develop the hypothesis that population changes reflect the human-mediated alteration of global ocean ecosystems. To this end, we synthesize information related to the evolutionary context of contemporary gelatinous zooplankton blooms, the human frame of reference forchanges in gelatinous zooplankton populations, and whether sufficient data are available to have established the paradigm. We conclude that the current paradigm in which it is believed that there has been a global increase in gelatinous zooplankton is unsubstantiated, and we develop a strategy for addressing the critical questions about long-term, human-related changes in the sea as they relate to gelatinous zooplankton blooms
Avalanches on a conical bead pile: scaling with tuning parameters
Uniform spherical beads were used to explore the behavior of a granular
system near its critical angle of repose on a conical bead pile. We found two
tuning parameters that could take the system to a critical point where a simple
power-law described the avalanche size distribution as predicted by
self-organized criticality, which proposed that complex dynamical systems
self-organize to a critical point without need for tuning. Our distributions
were well described by a simple power-law with the power {\tau} = 1.5 when
dropping beads slowly onto the apex of a bead pile from a small height.
However, we could also move the system from the critical point using either of
two tuning parameters: the height from which the beads fell onto the top of the
pile or the region over which the beads struck the pile. As the drop height
increased, the system did not reach the critical point yet the resulting
distributions were independent of the bead mass, coefficient of friction, or
coefficient of restitution. All our apex-dropping distributions for any type of
bead (glass, stainless steel, zirconium) showed universality by scaling onto a
common curve with {\tau} = 1.5 and {\sigma} = 1.0, where 1/{\sigma} is the
power of the tuning parameter. From independent calculations using the moments
of the distribution, we find values for {\tau} = 1.6 \pm 0.1 and {\sigma} =
0.91 \pm 0.15. When beads were dropped across the surface of the pile instead
of solely on the apex, then the system also moved from the critical point and
again the avalanche size distributions fell on a common curve when scaled
similarly using the same values of {\tau} and {\sigma}. We also observed that
an hcp structure on the base of the pile caused an emergent structure in the
pile that had six faces with some fcc or hcp structure.Comment: 8 pages, 6 figures; submitted to Granular Matter; Reformatted into
LaTeX from Word; Fixed typo in uncertainty of tau; Rearranged two paragraphs
to improve flo
Women write the rights of woman: The sexual politics of the personal pronoun in the 1790s
This article investigates patterns of personal pronoun usage in four texts written by women about women's rights during the 1790s: Mary Wollstonecraft's A Vindication of the Rights of Woman (1792), Mary Hays' An Appeal to the Men of Great Britain (1798), Mary Robinson's Letter to the Women of England (1799) and Mary Anne Radcliffe's The Female Advocate (1799). I begin by showing that at the time these texts were written there was a widespread assumption that both writers and readers of political pamphlets were, by default, male. As such, I argue, writing to women as a woman was distinctly problematic, not least because these default assumptions meant that even apparently gender-neutral pronouns such as I, we and you were in fact covertly gendered. I use the textual analysis programme WordSmith to identify the personal pronouns in my four texts, and discuss my results both quantitatively and qualitatively. I find that while one of my texts does little to disturb gender expectations through its deployment of personal pronouns, the other three all use personal pronouns that disrupt eighteenth century expectations about default male authorship and readership. Copyright © 2007 SAGE Publications
EHDV-2 Infection Prevalence Varies in Culicoides sonorensis after Feeding on Infected White-Tailed Deer over the Course of Viremia
Epizootic hemorrhagic disease viruses (EHDVs) are arboviral pathogens of white-tailed deer and other wild and domestic ruminants in North America. Transmitted by various species of Culicoides, EHDVs circulate wherever competent vectors and susceptible ruminant host populations co-exist. The impact of variation in the level and duration of EHDV viremia in white-tailed deer (Odocoileus virginianus) on Culicoides infection prevalence is not well characterized. Here we examined how infection prevalence in a confirmed North American vector of EHDV-2 (Culicoides sonorensis) varies in response to fluctuations in deer viremia. To accomplish this, five white-tailed deer were experimentally infected with EHDV-2 and colonized C. sonorensis were allowed to feed on deer at 3, 5, 7, 10, 12, 14, 18, and 24 days post infection (dpi). Viremia profiles in deer were determined by virus isolation and titration at the same time points. Blood-fed Culicoides were assayed for virus after a 10-day incubation (27 ◦C) period. We found that increases in deer EHDV blood titers significantly increased both the likelihood that midges would successfully acquire EHDV and the proportion of midges that reached the titer threshold for transmission competence. Unexpectedly, we identified four infected midge samples (three individuals and one pool) after feeding on one deer 18 and 24 dpi, when viremia was no longer detectable by virus isolation. The ability of ruminants with low-titer viremia to serve as a source of EHDV for blood-feeding Culicoides should be explored further to better understand its potential epidemiological significance
Implications of lowering threshold of plasma troponin concentration in diagnosis of myocardial infarction: cohort study
Objective To assess the relation between troponin concentration, assay precision, and clinical outcomes in patients with suspected acute coronary syndrome
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