2,921 research outputs found
Glutamatergic Plasticity in Medial Prefrontal Cortex and Ventral Tegmental Area Following Extended-Access Cocaine Self-Administration
Glutamate signaling in prefrontal cortex and ventral tegmental area plays an important role in the molecular and behavioral plasticity associated with addiction to drugs of abuse. The current study investigated the expression and postsynaptic density redistribution of glutamate receptors and synaptic scaffolding proteins in dorsomedial and ventromedial prefrontal cortex and ventral tegmental area after cocaine self-administration. After 14 days of extended-access (6 h/day) cocaine self-administration, rats were exposed to one of three withdrawal regimen for 10 days. Animals either stayed in home cages (Home), returned to self-administration boxes with the levers withdrawn (Box), or underwent extinction training (Extinction). Extinction training was associated with significant glutamatergic plasticity. In dorsomedial prefrontal cortex of the Extinction group, there was an increase in postsynaptic density GluR1, PSD95, and actin proteins; while postsynaptic density mGluR5 protein decreased and there was no change in NMDAR1, Homer1b/c, or PICK1 proteins. These changes were not observed in ventromedial prefrontal cortex or ventral tegmental area. In ventral tegmental area, Extinction training reversed the decreased postsynaptic density NMDAR1 protein in the Home and Box withdrawal groups. These data suggest that extinction of drug seeking is associated with selective glutamatergic plasticity in prefrontal cortex and ventral tegmental area that include modulation of receptor trafficking to postsynaptic density
The extent of population genetic subdivision differs among four co-distributed shark species in the Indo-Australian archipelago
Background: The territorial fishing zones of Australia and Indonesia are contiguous to the north of Australia in the Timor and Arafura Seas and in the Indian Ocean to the north of Christmas Island. The area surrounding the shared boundary consists of a variety of bio-diverse marine habitats including shallow continental shelf waters, oceanic trenches and numerous offshore islands. Both countries exploit a variety of fisheries species, including whaler (Carcharhinus spp.) and hammerhead sharks (Sphyrna spp.). Despite their differences in social and financial arrangements, the two countries are motivated to develop complementary co-management practices to achieve resource sustainability. An essential starting point is knowledge of the degree of population subdivision, and hence fisheries stock status, in exploited species. Results: Populations of four commercially harvested shark species (Carcharhinus obscurus, Carcharhinus sorrah, Prionace glauca, Sphyrna lewini) were sampled from northern Australia and central Indonesia. Neutral genetic markers (mitochondrial DNA control region sequence and allelic variation at co-dominant microsatellite loci) revealed genetic subdivision between Australian and Indonesian populations of C. sorrah. Further research is needed to address the possibility of genetic subdivision among C. obscurus populations. There was no evidence of genetic subdivision for P. glauca and S. lewini populations, but the sampling represented a relatively small part of their distributional range. For these species, more detailed analyses of population genetic structure is recommended in the future. Conclusion: Cooperative management between Australia and Indonesia is the best option at present for P. glauca and S. lewini, while C. sorrah and C. obscurus should be managed independently. On-going research on these and other exploited shark and ray species is strongly recommended. Biological and ecological similarity between species may not be a predictor of population genetic structure, so species-specific studies are recommended to provide new data to assist with sustainable fisheries management
Recommended from our members
Use of ArcGIS in Environmental Monitoring at Idaho National Laboratory
The Idaho National Laboratory is a U.S. Department of Energy site located in southeastern Idaho. The INL is required to perform environmental monitoring of anthropogenically introduced contaminants. One primary contaminant of interest is radioactive Cs-137 which is resident in INL soils due to past operational activities and atmospheric weapons testing. Collection of field data is performed using vehicle mounted and portable radiation detector units. All data is combined in ArcGIS and displayed over georeferenced satellite images and digital elevation models. The use of the ArcGIS geostatistical analysis package enhances the ability to look for areas of higher Cs-137 concentration. Combining current monitoring results with meteorological wind pattern maps allows for siting of new and improved monitoring locations. Use of the ArcGIS package provides an integrated analysis and mapping protocol for use in radioactive contaminant monitoring
Development of an evidence-based framework of factors contributing to patient safety incidents in hospital settings: a systematic review
Objective The aim of this systematic review was to develop a âcontributory factors frameworkâ from a synthesis of empirical work which summarises factors contributing to patient safety incidents in hospital settings. Design A mixed-methods systematic review of the literature was conducted. Data sources Electronic databases (Medline, PsycInfo, ISI Web of knowledge, CINAHL and EMBASE), article reference lists, patient safety websites, registered study databases and author contacts. Eligibility criteria Studies were included that reported data from primary research in secondary care aiming to identify the contributory factors to error or threats to patient safety. Results 1502 potential articles were identified. 95 papers (representing 83 studies) which met the inclusion criteria were included, and 1676 contributory factors extracted. Initial coding of contributory factors by two independent reviewers resulted in 20 domains (eg, team factors, supervision and leadership). Each contributory factor was then coded by two reviewers to one of these 20 domains. The majority of studies identified active failures (errors and violations) as factors contributing to patient safety incidents. Individual factors, communication, and equipment and supplies were the other most frequently reported factors within the existing evidence base. Conclusions This review has culminated in an empirically based framework of the factors contributing to patient safety incidents. This framework has the potential to be applied across hospital settings to improve the identification and prevention of factors that cause harm to patients
Second to fourth digit ratio (2D:4D) and concentrations of circulating sex hormones in adulthood
<p>Abstract</p> <p>Background</p> <p>The second to fourth digit ratio (2D:4D) is used as a marker of prenatal sex hormone exposure. The objective of this study was to examine whether circulating concentrations of sex hormones and SHBG measured in adulthood was associated with 2D:4D.</p> <p>Methods</p> <p>This analysis was based on a random sample from the Melbourne Collaborative Cohort Study. The sample consisted of of 1036 men and 620 post-menopausal women aged between 39 and 70 at the time of blood draw. Concentrations of circulating sex hormones were measured from plasma collected at baseline (1990-1994), while digit length was measured from hand photocopies taken during a recent follow-up (2003-2009). The outcome measures were circulating concentrations of testosterone, oestradiol, dehydroepiandrosterone sulphate, androstenedione, Sex Hormone Binding Globulin, androstenediol glucoronide for men only and oestrone sulphate for women only. Free testosterone and oestradiol were estimated using standard formulae derived empirically. Predicted geometric mean hormone concentrations (for tertiles of 2D:4D) and conditional correlation coefficients (for continuous 2D:4D) were obtained using mixed effects linear regression models.</p> <p>Results</p> <p>No strong associations were observed between 2D:4D measures and circulating concentrations of hormones for men or women. For males, right 2D:4D was weakly inversely associated with circulating testosterone (predicted geometric mean testosterone was 15.9 and 15.0 nmol/L for the lowest and highest tertiles of male right 2D:4D respectively (<it>P</it>-<it>trend </it>= 0.04). There was a similar weak association between male right 2D:4D and the ratio of testosterone to oestradiol. These associations were not evident in analyses of continuous 2D:4D.</p> <p>Conclusions</p> <p>There were no strong associations between any adult circulating concentration of sex hormone or SHGB and 2D:4D. These results contribute to the growing body of evidence indicating that 2D:4D is unrelated to adult sex hormone concentrations.</p
Recommended from our members
Real Time Quantitative Radiological Monitoring Equipment for Environmental Assessment
The Idaho National Laboratory (INL) has developed a suite of systems that rapidly scan, analyze, and characterize radiological contamination in soil. These systems have been successfully deployed at several Department of Energy (DOE) laboratories and Cold War Legacy closure sites. Traditionally, these systems have been used during the characterization and remediation of radiologically contaminated soils and surfaces; however, subsequent to the terrorist attacks of September 11, 2001, the applications of these systems have expanded to include homeland security operations for first response, continuing assessment and verification of cleanup activities in the event of the detonation of a radiological dispersal device. The core system components are a detector, a spectral analyzer, and a global positioning system (GPS). The system is computer controlled by menu-driven, user-friendly custom software designed for a technician-level operator. A wide variety of detectors have been used including several configurations of sodium iodide (NaI) and high-purity germanium (HPGe) detectors, and a large area proportional counter designed for the detection of x-rays from actinides such as Am-241 and Pu-238. Systems have been deployed from several platforms including a small all-terrain vehicle (ATV), hand-pushed carts, a backpack mounted unit, and an excavator mounted unit used where personnel safety considerations are paramount. The INL has advanced this concept, and expanded the system functionality to create an integrated, field-deployed analytical system through the use of tailored analysis and operations software. Customized, site specific software is assembled from a supporting toolbox of algorithms that streamline the data acquisition, analysis and reporting process. These algorithms include region specific spectral stripping, automated energy calibration, background subtraction, activity calculations based on measured detector efficiencies, and on-line data quality checks and measures. These analyses are combined to provide real-time areal activity and coverage maps that are displayed to the operator as the survey progresses. The flexible functionality of the INL systems are well suited to multiple roles supporting homeland security needs
Recommended from our members
Radiological Monitoring Equipment For Real-Time Quantification Of Area Contamination In Soils And Facility Decommissioning
The environmental restoration industry offers several sysÂŹtems that perform scan-type characterization of radiologically contaminated areas. The Idaho National Laboratory (INL) has developed and deployed a suite of field systems that rapidly scan, characterize, and analyse radiological contamination in surface soils. The base system consists of a detector, such as sodium iodide (NaI) spectrometers, a global positioning system (GPS), and an integrated user-friendly computer interface. This mobile concept was initially developed to provide precertificaÂŹtion analyses of soils contaminated with uranium, thorium, and radium at the Fernald Closure Project, near Cincinnati, Ohio. INL has expanded the functionality of this basic system to create a suite of integrated field-deployable analytical systems. Using its engineering and radiation measurement expertise, aided by computer hardware and software support, INL has streamlined the data acquisition and analysis process to provide real-time information presented on wireless screens and in the form of coverage maps immediately available to field technicians. In addition, custom software offers a user-friendly interface with user-selectable alarm levels and automated data quality monitoring functions that validate the data. This system is deployed from various platforms, depending on the nature of the survey. The deployment platforms include a small all-terrain vehicle used to survey large, relatively flat areas, a hand-pushed unit for areas where manoeuvrability is important, an excavator-mounted system used to scan pits and trenches where personnel access is restricted, and backpack- mounted systems to survey rocky shoreline features and other physical settings that preclude vehicle-based deployment. Variants of the base system include sealed proportional counters for measuring actinides (i.e., plutonium-238 and americium-241) in building demolitions, soil areas, roadbeds, and process line routes at the Miamisburg Closure Project near Dayton, Ohio. In addition, INL supports decontamination operations at the Oak Ridge National Laboratory
Tracing the String: BMN correspondence at Finite J^2/N
Employing the string bit formalism of hep-th/0209215, we identify the basis
transformation that relates BMN operators in N=4 gauge theory to string states
in the dual string field theory at finite g_2=J^2/N. In this basis, the
supercharge truncates at linear order in g_2, and the mixing amplitude between
1 and 2-string states precisely matches with the (corrected) answer of
hep-th/0206073 for the 3-string amplitude in light-cone string field theory.
Supersymmetry then predicts the order g_2^2 contact term in the string bit
Hamiltonian. The resulting leading order mass renormalization of string states
agrees with the recently computed shift in conformal dimension of BMN operators
in the gauge theory.Comment: 11 pages, 1 figur
- âŠ