92 research outputs found
Inshore spawning of cobia (Rachycentron canadum) in South Carolina
We documented inshore spawning of the recreationally important cobia (Rachycentron canadum) in Port Royal Sound (PRS) and St. Helena Sound (SHS), South Carolina, during the period from April to June in both 2007 and 2008. Histological analysis of ovaries confirmed the presence of actively spawning females inshore, and gonadosomatic index (GSI) values from females collected inshore (mean=7.8) were higher than the values from females caught offshore (mean=5.6); both of these mean values indicate that spawning occurred locally. Additionally, we conducted an ichthyoplankton survey in 2008 and found cobia eggs and larvae as far as 10 and 15 km inshore from the mouths of SHS and PRS, respectively. A study of egg development that we conducted in 2007 and 2008 using hatchery-reared cobia eggs provided descriptions of embryological development of cobia. Comparison of visual and quantitative characteristics of the field-collected eggs with those of the hatchery-reared eggs allowed positive identification of eggs collected in plankton samples. The ages of field-collected eggs and presence of females with hydrated oocytes in PRS and SHS observed in our ichthyoplankton survey and histological analysis indicated that wild cobia spawn in the afternoon and early evening. The inshore migration of cobia from April to June, the presence of actively spawning females, significantly higher GSI values, and the collection of eggs inside PRS and SHS all confirm that these estuaries provide spawning habitat for cobia. Because of the potential for heavy exploitation by recreational anglers as cobia move inshore to spawn in South Carolina, current management strategies may require review
Population genetics of Cobia (Rachycentron canadum): implications for fishery management along the coast of the southeastern United States
Cobia (Rachycentron canadum) is a pelagic, migratory species with a transoceanic distribution in tropical and subtropical waters. Recreational fishing pressure on Cobia in the United States has increased substantially during the last decade, especially in areas of its annual inshore aggregations, making this species potentially susceptible to overfishing. Although Cobia along the Atlantic and Gulf coasts of the southeastern United States are currently managed as a single fishery, the genetic composition of Cobias in these areas is unclear. On the basis of a robust microsatellite data set from collections along the U.S. Atlantic coast (2008â09), offshore groups were genetically homogenous. However, the 2 sampled inshore aggregations (South Carolina and Virginia) were genetically distinct from each other, as well as from the offshore group. The recapture of stocked fish within their release estuary 2 years after release indicates that some degree of estuarine fidelity occurs within these inshore aggregations and supports the detection of their unique genetic structure at the population level. These results complement the observed high site fidelity of Cobias in South Carolina and support a recent study that confirms that Cobia spawn in the inshore aggregations. Our increased understanding of Cobia life history will be beneficial for determining the appropriate scale of fishery management for Cobia
Tag-reporting levels for red drum (Sciaenops ocellatus) caught by anglers in South Carolina and Georgia estuaries
A total of 1784 legal-size (â„356 mm TL) hatchery-produced red drum (Sciaenops ocellatus) were tagged and released to estimate tag-reporting levels of recreational anglers in South Carolina (SC) and Georgia (GA). Twelve groups of legal-size fish (~150 fish/ group) were released. Half of the fish of each group were tagged with an external tag with the message ârewardâ and the other half of the fish were implanted with tags with the message â100/tag. Reporting level for the ârewardâtags was estimated by dividing the number of ârewardâ tags returned by the number of â100 rewardâ tags were returned. This finding indicates that only 56.7% of the fish captured with ârewardâ tags were reported in SC. The pattern was similar for GA where 19.1 (±10.6)% of ârewardâ message tags were returned as compared with 30.1 (±15.6)% for â$100 rewardâ message tags. This difference yielded a reporting level of 63% for ârewardâ tags in GA. Currently, 50% is used as the estimate for the angler reporting level in population models for red drum and a number of other coastal finfish species in the South Atlantic region of the United States. Based on results of our study, the commonly used reporting estimate may result in an overestimate of angler exploitation for red drum
COVID-19 Outcomes Stratified by Control Status of Hypertension and Diabetes: Preliminary Findings From PCORnet, U.S
INTRODUCTION: Hypertension and diabetes are associated with increased COVID-19 severity, yet less is known about COVID-19 outcomes across levels of disease control for these conditions. METHODS: All adults aged â„20 years with COVID-19 between March 1, 2020 and March 15, 2021 in 42 healthcare systems in National Patient-Centered Clinical Research Network were identified. RESULTS: Among 656,049 adults with COVID-19, 41% had hypertension, and 13% had diabetes. Of patients with classifiable hypertension, 35% had blood pressure <130/80 mmHg, 40% had blood pressure of 130â139/80â89 mmHg, 21% had blood pressure of 140â159/90â99 mmHg, and 6% had blood pressure â„160/100 mmHg. Severe COVID-19 outcomes were more prevalent among those with blood pressure of â„160/100 than among those with blood pressure of 130-139/80-89, including hospitalization (23.7% [95% CI=23.0, 24.4] vs 11.7% [95% CI=11.5, 11.9]), receipt of critical care (5.5% [95% CI=5.0, 5.8] vs 2.4% [95% CI=2.3, 2.5]), receipt of mechanical ventilation (3.0% [95% CI=2.7, 3.3] vs 1.2% [95% CI=1.1, 1.3]), and 60-day mortality (4.6% [95% CI=4.2, 4.9] vs 1.8% [95% CI=1.7, 1.9]). Of patients with classifiable diabetes, 44% had HbA1c <7%, 35% had HbA1c 7% to <9%, and 21% had HbA1c â„9%. Hospitalization prevalence was 31.3% (95% CI=30.7, 31.9) among those with HbA1c <7% vs 40.2% (95% CI=39.4, 41.1) among those with HbA1c â„9%; other outcomes did not differ substantially by HbA1c. CONCLUSIONS: These findings highlight the importance of appropriate management of hypertension and diabetes, including during public health emergencies such as the COVID-19 pandemic
Prediction of complicated disease course for children newly diagnosed with Crohn's disease: a multicentre inception cohort study
Stricturing and penetrating complications account for substantial morbidity and health-care costs in paediatric and adult onset Crohnâs disease. Validated models to predict risk for complications are not available, and the effect of treatment on risk is unknown
Global comparison of warring groups in 2002â2007: fatalities from targeting civilians vs. fighting battles
Background
Warring groups that compete to dominate a civilian population confront contending behavioral options: target civilians or battle the enemy. We aimed to describe degrees to which combatant groups concentrated lethal behavior into intentionally targeting civilians as opposed to engaging in battle with opponents in contemporary armed conflict.
Methodology/Principal Findings
We identified all 226 formally organized state and non-state groups (i.e. actors) that engaged in lethal armed conflict during 2002â2007: 43 state and 183 non-state. We summed civilians killed by an actor's intentional targeting with civilians and combatants killed in battles in which the actor was involved for total fatalities associated with each actor, indicating overall scale of armed conflict. We used a Civilian Targeting Index (CTI), defined as the proportion of total fatalities caused by intentional targeting of civilians, to measure the concentration of lethal behavior into civilian targeting. We report actor-specific findings and four significant trends: 1.) 61% of all 226 actors (95% CI 55% to 67%) refrained from targeting civilians. 2.) Logistic regression showed actors were more likely to have targeted civilians if conflict duration was three or more years rather than one year. 3.) In the 88 actors that targeted civilians, multiple regressions showed an inverse correlation between CTI values and the total number of fatalities. Conflict duration of three or more years was associated with lower CTI values than conflict duration of one year. 4.) When conflict scale and duration were accounted for, state and non-state actors did not differ. We describe civilian targeting by actors in prolonged conflict. We discuss comparable patterns found in nature and interdisciplinary research.
Conclusions/Significance
Most warring groups in 2002â2007 did not target civilians. Warring groups that targeted civilians in small-scale, brief conflict concentrated more lethal behavior into targeting civilians, and less into battles, than groups in larger-scale, longer conflict
Meta-Analysis in Higher Education: An Illustrative Example Using Hierarchical Linear Modeling
The purpose of this article is to provide higher education researchers with an illustrative example of meta-analysis utilizing hierarchical linear modeling (HLM). This article demonstrates the step-by-step process of meta-analysis using a recently-published study examining the effects of curricular and co-curricular diversity activities on racial bias in college students as an example (Denson, Rev Educ Res 79:805-838, 2009). The authors present an overview of the meta-analytic approach and describe a meta-analysis from beginning to end. The example includes: problem specification; research questions; study retrieval and selection; coding procedure; calculating effect sizes; visual displays and summary statistics; conducting HLM analyses; and sensitivity analyses. The authors also offer guidelines and recommendations for improving the conduct and reporting of research which in turn can provide the information necessary for future and more comprehensive meta-analytic reviews
Challenges in IBD Research: Update on Progress and Prioritization of the CCFAÊŒs Research Agenda
Acute mountain sickness.
Acute mountain sickness (AMS) is a clinical syndrome occurring in otherwise healthy normal individuals who ascend rapidly to high altitude. Symptoms develop over a period ofa few hours or days. The usual symptoms include headache, anorexia, nausea, vomiting, lethargy, unsteadiness of gait, undue dyspnoea on moderate exertion and interrupted sleep. AMS is unrelated to physical fitness, sex or age except that young children over two years of age are unduly susceptible. One of the striking features ofAMS is the wide variation in individual susceptibility which is to some extent consistent. Some subjects never experience symptoms at any altitude while others have repeated attacks on ascending to quite modest altitudes. Rapid ascent to altitudes of 2500 to 3000m will produce symptoms in some subjects while after ascent over 23 days to 5000m most subjects will be affected, some to a marked degree. In general, the more rapid the ascent, the higher the altitude reached and the greater the physical exertion involved, the more severe AMS will be. Ifthe subjects stay at the altitude reached there is a tendency for acclimatization to occur and symptoms to remit over 1-7 days
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