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Localized contamination from research-related activities and its effects on macrofauna communities in the marine environment were investigated at Palmer Station, a medium-sized Antarctic research station. Relatively low concentrations of polycyclic aromatic hydrocarbons (PAHs; 32–302 ng g-1) and total petroleum hydrocarbons (TPHs; 0.9–8.9 μg g-1) were detected in sediments adjacent to the sewage outfall and pier, where most human activities were expected to have occurred, and at even lower concentrations at two seemingly reference areas (PAHs 6–30 ng g-1, TPHs 0.03–5.1 μg g-1). Elevated concentrations of PAHs in one sample taken in one reference area (816 ng g-1) and polychlorinated biphenyls (353 ng g-1) and dichloro-diphenyl-trichloroethane (3.2 and 25.3 ng g-1) in two samples taken adjacent to the sewage outfall indicate spatial heterogeneity of localized sediment contamination. Limpet (Nacella concinna) tissues collected adjacent to Palmer Station had high concentrations of PAHs, copper, lead, zinc and several other metals relative to outlying islands. Sediment and limpet tissue contaminant concentrations have decreased since the early 1990s following the Bahía Paraíso spill. Natural sediment characteristics affected macrofaunal community composition more than contamination adjacent to Palmer Station, presumably because of the low overall contamination levels.
Mild cognitive impairment (MCI) types may have distinct neuropathological substrates with hippocampal atrophy particularly common in amnestic MCI (aMCI). However, depending on the MCI classification criteria applied to the sample (e.g., number of abnormal test scores considered or thresholds for impairment), volumetric findings between MCI types may change. Additionally, despite increased clinical use, no prior research has examined volumetric differences in MCI types using the automated volumetric software, Neuroreader™.
The present study separately applied the Petersen/Winblad and Jak/Bondi MCI criteria to a clinical sample of older adults (N = 82) who underwent neuropsychological testing and brain MRI. Volumetric data were analyzed using Neuroreader™ and hippocampal volumes were compared between aMCI and non-amnestic MCI (naMCI).
T-tests revealed that regardless of MCI classification criteria, hippocampal volume z-scores were significantly lower in aMCI compared to naMCI (p’s < .05), and hippocampal volume z-scores significantly differed from 0 (Neuroreader™ normative mean) in the aMCI group only (p’s < .05). Additionally, significant, positive correlations were found between measures of delayed recall and hippocampal z-scores in aMCI using either MCI classification criteria (p’s < .05).
We provide evidence of correlated neuroanatomical changes associated with memory performance for two commonly used neuropsychological MCI classification criteria. Future research should investigate the clinical utility of hippocampal volumes analyzed via Neuroreader™ in MCI.
This study examined the relationship between patient performance on multiple memory measures and regional brain volumes using an FDA-cleared quantitative volumetric analysis program – Neuroreader™.
Ninety-two patients diagnosed with mild cognitive impairment (MCI) by a clinical neuropsychologist completed cognitive evaluations and underwent MR Neuroreader™ within 1 year of testing. Select brain regions were correlated with three widely used memory tests. Regression analyses were conducted to determine if using more than one memory measures would better predict hippocampal z-scores and to explore the added value of recognition memory to prediction models.
Memory performances were most strongly correlated with hippocampal volumes than other brain regions. After controlling for encoding/Immediate Recall standard scores, statistically significant correlations emerged between Delayed Recall and hippocampal volumes (rs ranging from .348 to .490). Regression analysis revealed that evaluating memory performance across multiple memory measures is a better predictor of hippocampal volume than individual memory performances. Recognition memory did not add further predictive utility to regression analyses.
This study provides support for use of MR Neuroreader™ hippocampal volumes as a clinically informative biomarker associated with memory performance, which is a critical diagnostic feature of MCI phenotype.
Historically, the cardiac catheterization laboratory has been used for blood sampling, contrast-enhanced imaging and intravascular pressure measurement to provide diagnostic and prognostic information and to guide surgical intervention. In recent years, technological advancements have made less invasive therapies feasible and driven tremendous growth in percutaneous procedures. While this now encompasses a wide range of cardiovascular interventions, this chapter will focus on percutaneous therapies for structural heart disease, where the anaesthetist is most likely to be involved.
In the United States, tornadoes are the third leading cause of fatalities from natural disasters1. To aid prevention and mitigation of tornado-related morbidity and mortality, improvement in standardizing tornado specific threat analysis terminology was assessed. The largest number of tornado-related fatalities has occurred in the state of Texas for over a hundred years. The occurrence of tornadic clusters or “outbreaks” has not been formally standardized. The concept of “tornado outbreaks” is better defined and its role in fatality mitigation is addressed in this Institutional Review Board (IRB) approved study.
To understand the role of “tornado outbreaks” related clusters in Texas in relationship to morbidity and mortality.
This IRB approved (IRB2017- 0507) research study utilized GIS tools and statistical analysis of historical data to examine the relationship between tornado severity (based on the Fujita Scale), the number of tornadoes, and the trends in morbidity and mortality. This study was funded in part from The National Science Foundation grant (NSF Grant #1560106) in support of the CyberHealthGIS Research Experience for Undergraduates (REU).
A statistically significant difference was demonstrated between the severity of a tornado and related morbidity and mortality during “tornado outbreaks” in Texas during a defined 30-year period.
Understanding the role and discerning the impacts of “tornado outbreaks” as related to tornado severity has critical implications to disaster preparedness. Applications of this conclusion may improve shelter planning/preparation, timely warning, and educating the at-risk public. Subsequently, examining the likelihood and improved descriptions of “tornado outbreaks” may aid in reducing the number of tornado-related injuries and fatalities nationally.
Objectives: Research on developmental outcomes of preterm birth has traditionally focused on adverse effects. This study investigated the prevalence and correlates of resilience in 146 extremely preterm/extremely low birth weight (EPT/ELBW) children (gestational age <28 weeks and/or birth weight <1000 g) attending kindergarten and 111 term-born normal birth weight (NBW) controls. Methods: Adaptive competence (i.e., “resilience” in the EPT/ELBW group) was defined by scores within grade expectations on achievement tests and the absence of clinically elevated parent ratings of child behavior problems. The “adaptive” children who met these criteria were compared to the “maladaptive” children who did not on child and family characteristics. Additional analyses were conducted to assess the conjoint effects of group (ELBW vs. NBW) and family factors on adaptive competence. Results: A substantial minority of the EPT/ELBW group (45%) were competent compared to a majority of NBW controls (73%), odds ratio (95% confidence interval)=0.26 (0.15, 0.45), p<.001. Adaptive competence was associated with higher cognitive skills, more favorable ratings of behavior and learning not used to define adaptive competence, and more advantaged family environments in both groups, as well as with a lower rate of earlier neurodevelopmental impairment in the EPT/ELBW group. Higher socioeconomic status and more favorable proximal home environments were associated with competence independent of group, and group differences in competence persisted across the next two school years. Conclusions: The findings document resilience in kindergarten children with extreme prematurity and highlight the role of environmental factors as potential influences on outcome. (JINS, 2019, 25, 362–374)
We take up here an issue that is becoming increasingly urgent for New Formalist studies: how verse is lineated or set out in surviving medieval manuscripts, and how the decisive moment of arranging a text on the page reveals an authorial or scribal awareness of transitions in form. In such moments, we argue, authors or scribes looked both backward toward their forebears for inspiration and also outward toward new multicultural influences as English poetry developed. As the work of Ardis Butterfield and many other scholars of manuscript studies over three decades has shown, contextualizing poetic form in its manuscript presentation illuminates the “poetically engaging” moment when the pre-written, notional sense of a poem “is negotiated into written form by medieval poets.” In the (re)turn to formalism, the urgency of this contextualization lies in our collective interest in preserving the benefits that decades of historical and historicist scholarship have given to the field, in no small way thanks to interest in manuscripts. New Criticism operated in a world largely innocent of manuscript studies: manuscripts were considered important only to editors, whose job was to mediate between the inconvenient, often obscure manuscript page and the comforts of modern print. While mid-twentieth-century scholars usually had enough old-school philology to know that editors had regularized Middle English orthography, they had little interest in how their editors had regulated form, creating metrically tidy lyrics even where a scribe had emphasized fluidity or its playful possibilities. And even New Criticism's editors regarded paleography as the purview of a handful of temporarily useful specialists, who, they imagined, had little to contribute beyond transcription and dating. Paleography for vernacular texts was also slow to develop: in his memoirs, for instance, George Kane records the great difficulty he had even finding a paleographer willing to deal with Middle English when he was first editing the A-text of Piers Plowman. All that began to change only when innovative paleographers such as Malcolm Parkes and Ian Doyle began to excavate medieval terminology for book organization (e.g., the term ordinatio, stemming from the Oxford requirement that medieval lecturers discuss the organization and structure of a prescribed text), and when editors such as Derek Pearsall began to realize that manuscripts did not just transmit stories, but could also tell them.
Little is known about potential harmful effects as a consequence of self-guided internet-based cognitive behaviour therapy (iCBT), such as symptom deterioration rates. Thus, safety concerns remain and hamper the implementation of self-guided iCBT into clinical practice. We aimed to conduct an individual participant data (IPD) meta-analysis to determine the prevalence of clinically significant deterioration (symptom worsening) in adults with depressive symptoms who received self-guided iCBT compared with control conditions. Several socio-demographic, clinical and study-level variables were tested as potential moderators of deterioration.
Randomised controlled trials that reported results of self-guided iCBT compared with control conditions in adults with symptoms of depression were selected. Mixed effects models with participants nested within studies were used to examine possible clinically significant deterioration rates.
Thirteen out of 16 eligible trials were included in the present IPD meta-analysis. Of the 3805 participants analysed, 7.2% showed clinically significant deterioration (5.8% and 9.1% of participants in the intervention and control groups, respectively). Participants in self-guided iCBT were less likely to deteriorate (OR 0.62, p < 0.001) compared with control conditions. None of the examined participant- and study-level moderators were significantly associated with deterioration rates.
Self-guided iCBT has a lower rate of negative outcomes on symptoms than control conditions and could be a first step treatment approach for adult depression as well as an alternative to watchful waiting in general practice.
Understanding the removal of energy from turbulent fluctuations in a magnetized plasma and the consequent energization of the constituent plasma particles is a major goal of heliophysics and astrophysics. Previous work has shown that nonlinear interactions among counterpropagating Alfvén waves – or Alfvén wave collisions – are the fundamental building block of astrophysical plasma turbulence and naturally generate current sheets in the strongly nonlinear limit. A nonlinear gyrokinetic simulation of a strong Alfvén wave collision is used to examine the damping of the electromagnetic fluctuations and the associated energization of particles that occurs in self-consistently generated current sheets. A simple model explains the flow of energy due to the collisionless damping and the associated particle energization, as well as the subsequent thermalization of the particle energy by collisions. The net particle energization by the parallel electric field is shown to be spatially localized, and the nonlinear evolution is essential in enabling spatial non-uniformity. Using the recently developed field–particle correlation technique, we show that particles resonant with the Alfvén waves in the simulation dominate the energy transfer, demonstrating conclusively that Landau damping plays a key role in the spatially localized damping of the electromagnetic fluctuations and consequent energization of the particles in this strongly nonlinear simulation.
On August 25, 2017, Hurricane Harvey made landfall near Corpus Christi, Texas. The ensuing unprecedented flooding throughout the Texas coastal region affected millions of individuals.1 The statewide response in Texas included the sheltering of thousands of individuals at considerable distances from their homes. The Dallas area established large-scale general population sheltering as the number of evacuees to the area began to amass. Historically, the Dallas area is one familiar with “mega-sheltering,” beginning with the response to Hurricane Katrina in 2005.2 Through continued efforts and development, the Dallas area had been readying a plan for the largest general population shelter in Texas. (Disaster Med Public Health Preparedness. 2019;13:33–37)
This research project seeks to contribute to the literature on management by presenting and testing a model of leadership linking leadership styles directly to culture type and indirectly to firm effectiveness. The authors selected a four-factor theory of leadership and examined how it directly impacted organizational culture, and indirectly impacted organizational effectiveness (via an organization's culture). Using surveys designed to measure attitudinal and behavioral indicators of organizational culture, leadership, and effectiveness, we collected data from 2,662 individuals in 311 organizations. The results generally support the hypotheses that organizational effectiveness is related to type of culture and that cultural norms are related to type of leadership styles. The results have implications for management and organizational development practices and processes. The results indicate that the leadership skills of managers and supervisors are critical factors in the creation and reinforcement of cultural norms. Furthermore, cultural norms seem to positively impact organizational effectiveness.