3,495 research outputs found

    Regulation of Ventral Tegmental Area Dopamine Neuron Activity by Feeding-related Hypothalamic Neuropeptides

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    The prevalence of obesity has doubled worldwide since the 1980s, and having a high body mass index contributes to more deaths worldwide than being underweight. Over the past 20 years, consumption of calorie-dense foods has increased, and this is considered one of the major causes of the rapid rise in obesity. Thus, understanding the neural control of food intake is important for the development of new and effective treatments of obesity. Two important brain regions that regulate food intake are the hypothalamus and the mesocorticolimbic dopamine system. The hypothalamus is essential for the homeostatic control of feeding and body weight, while the mesocorticolimbic dopamine system, also known as the reward system, is the primary circuit for reward and motivated behavior. The reward system also regulates food intake and food reward, and there is increasing evidence that hypothalamic feeding-related neuropeptides alter dopamine neuron activity to affect feeding. Nevertheless, how these neuropeptides interact with the reward system to regulate feeding is not fully understood. For example, centrally delivered neurotensin and neuropeptide-Y (NPY) increase dopamine release in the nucleus accumbens, but cause opposite effects on food reward. In addition, injection of the hypothalamic neuropeptides neurotensin, NPY, or alpha-melanocyte-stimulating hormone (a-MSH) into the ventral tegmental area (VTA), where reward-related dopamine neurons are located, alters multiple aspects of feeding, but how these neuropeptides interact with the reward system to alter feeding at both the circuit and cellular levels is not fully understood. In these studies, I have used whole cell patch-clamp electrophysiology in acute brain slices from mice to examine how neurotensin, a-MSH, and NPY affect VTA dopamine neuron activity. I have demonstrated that these neuropeptides use multiple mechanisms to alter VTA dopamine neuron activity, including both pre- and post-synaptic mechanisms. Neurotensin and a-MSH increased dopamine neuron activity, while NPY had both excitatory and inhibitory effects on dopamine neuron activity. Overall, these studies provide an important advancement in our understanding of the different mechanisms utilized by hypothalamic neuropeptides to alter VTA dopamine neuron activity and how hypothalamic neuropeptides interact with the mesocorticolimbic dopamine system to control food intake and food reward

    Improving Proficiency in Central Venous Catheter Insertion: Standardized Simulation Based Training for Internal Medicine House Staff

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    Objectives: The objectives of this study are to assess residents\u27 pre-workshop ability and comfort with CVC placement, undergo a standardized online didactic and hands-on clinical training simulation workshop, and subsequently undergo a proficiency test using simulation models to assess competency. The goal of a standardized training module is to create a universal approach to CVC placement in our institution and improve comfort and technical ability of house staff. We hypothesize that this will reduce complications and improve patient care and safety.https://jdc.jefferson.edu/patientsafetyposters/1063/thumbnail.jp

    Parents....an Invaluable Link to Student Success

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    Research demonstrates the strong correlation between parental involvement and student achievement. This research, which involves studies that highlight the outcomes of parental involvement, will be presented. In addition, examples of parental involvement from tiers 1, 2, and 3 in the various PBIS systems in northwest Georgia will be given. Haralson County Schools will provide specific examples on how they have included not only parents, but also community stakeholders in their quest to increase participation. They will discuss specific strategies on how to engage parent/community stakeholders on a limited budget. Participants will walk away with ideas and strategies that have been successful in seven PBIS systems in northwest Georgia

    On the infrared behaviour of 3d Chern-Simons theories in N=2 superspace

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    We discuss the problem of infrared divergences in the N=2 superspace approach to classically marginal three-dimensional Chern-Simons-matter theories. Considering the specific case of ABJM theory, we describe the origin of such divergences and offer a prescription to eliminate them by introducing non-trivial gauge-fixing terms in the action. We also comment on the extension of our procedure to higher loop order and to general three-dimensional Chern-Simons-matter models.Comment: 26 pages, 6 figures, JHEP3; v2: minor corrections and references added; v3: introduction expanded, presentation of section 3.3.1 improved, references added, version to appear in JHE

    An analysis of the performance of Black African junior provincial cricket batsmen

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    Objectives. This study investigated the difference in performance of white (W), coloured/Indian (C/I) and black African (BA) cricket batsmen at a junior provincial level in South Africa over a period of 7 years. Methods. Data of all players participating in the South African interprovincial under-15 (U15) and under-19 (U19) tournaments between the years 2004 and 2010 were analysed. The number of participants, batting averages and number of batsmen in the top 20 run scorers in the tournament were compared between groups. Results. 52% of players were white and 48% were black (27% BA and 21% C/I). BA batting averages (runs/dismissal) were significantly (p<0.05) lower than W batting averages for every year from 2004 to 2010 for both the U15 and U19s. W batsmen only had significantly better batting averages than C/I for the U/15s in 2010 and for the U19s in 2009 and 2010. W batsmen dominated the top 20 run scorers in the tournament in each year for both U15s and U19s while there were few BA batsmen represented in the top 20. Conclusion. The performances of BA batsmen at junior provincial level are well below those of W batsmen and appear to follow the same trend as the senior provincial batsmen

    VEZF1 elements mediate protection from DNA methylation

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    There is growing consensus that genome organization and long-range gene regulation involves partitioning of the genome into domains of distinct epigenetic chromatin states. Chromatin insulator or barrier elements are key components of these processes as they can establish boundaries between chromatin states. The ability of elements such as the paradigm β-globin HS4 insulator to block the range of enhancers or the spread of repressive histone modifications is well established. Here we have addressed the hypothesis that a barrier element in vertebrates should be capable of defending a gene from silencing by DNA methylation. Using an established stable reporter gene system, we find that HS4 acts specifically to protect a gene promoter from de novo DNA methylation. Notably, protection from methylation can occur in the absence of histone acetylation or transcription. There is a division of labor at HS4; the sequences that mediate protection from methylation are separable from those that mediate CTCF-dependent enhancer blocking and USF-dependent histone modification recruitment. The zinc finger protein VEZF1 was purified as the factor that specifically interacts with the methylation protection elements. VEZF1 is a candidate CpG island protection factor as the G-rich sequences bound by VEZF1 are frequently found at CpG island promoters. Indeed, we show that VEZF1 elements are sufficient to mediate demethylation and protection of the APRT CpG island promoter from DNA methylation. We propose that many barrier elements in vertebrates will prevent DNA methylation in addition to blocking the propagation of repressive histone modifications, as either process is sufficient to direct the establishment of an epigenetically stable silent chromatin stat

    Optimally combining dynamical decoupling and quantum error correction

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    We show how dynamical decoupling (DD) and quantum error correction (QEC) can be optimally combined in the setting of fault tolerant quantum computing. To this end we identify the optimal generator set of DD sequences designed to protect quantum information encoded into stabilizer subspace or subsystem codes. This generator set, comprising the stabilizers and logical operators of the code, minimizes a natural cost function associated with the length of DD sequences. We prove that with the optimal generator set the restrictive local-bath assumption used in earlier work on hybrid DD-QEC schemes, can be significantly relaxed, thus bringing hybrid DD-QEC schemes, and their potentially considerable advantages, closer to realization.Comment: 6 pages, 1 figur

    Toward evidence-based teaching: evaluating the effectiveness of two teaching strategies in an associate degree nursing program

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    The need for evidence based teaching has become an important ideology for nurse educators who are frequently encouraged to expand their teaching strategies based on recent advances in technology and student learning styles. Traditional lecture is often preferred by students, yet the literature encourages case study methodology for the development of critical thinking. A pilot study was conducted comparing learning outcomes using two different teaching strategies: lecture and case study instruction. Recommendations for using case study as a teaching methodology are offered

    A Geometric Approach to CP Violation: Applications to the MCPMFV SUSY Model

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    We analyze the constraints imposed by experimental upper limits on electric dipole moments (EDMs) within the Maximally CP- and Minimally Flavour-Violating (MCPMFV) version of the MSSM. Since the MCPMFV scenario has 6 non-standard CP-violating phases, in addition to the CP-odd QCD vacuum phase \theta_QCD, cancellations may occur among the CP-violating contributions to the three measured EDMs, those of the Thallium, neutron and Mercury, leaving open the possibility of relatively large values of the other CP-violating observables. We develop a novel geometric method that uses the small-phase approximation as a starting point, takes the existing EDM constraints into account, and enables us to find maximal values of other CP-violating observables, such as the EDMs of the Deuteron and muon, the CP-violating asymmetry in b --> s \gamma decay, and the B_s mixing phase. We apply this geometric method to provide upper limits on these observables within specific benchmark supersymmetric scenarios, including extensions that allow for a non-zero \theta_QCD.Comment: 34 pages, 16 eps figures, to appear in JHE
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