Star formation history in the solar neighborhood: the link between stars and cosmology

Using a cosmological galactic evolutionary approach to model the Milky Way, we calculate the star formation history (SFH) of the solar neighborhood. The good agreement we obtain with the observational inferences suggests that our physical model describes accurately the long term/large spatial trends of the local and global Milky Way SFH. In this model, star formation is triggered by disk gravitational instabilities and self-regulated by an energy balance in the ISM. The drivers of the SFH are the cosmological gas infall rate and the gas surface density determined by the primordial spin parameter. A LambdaCDM cosmology was used throughout.Comment: 8 pages, uses kluwer.cls. Invited talk, to appear in "New Quests in Stellar Astrophysics: The link between Stars and Cosmology", eds. M. Chavez, A. Bressan, A. Buzzoni & D. Mayya, Kluwer Academic Publisher

The VirusBanker database uses a Java program to allow flexible searching through Bunyaviridae sequences

<p>Abstract</p> <p>Background</p> <p>Viruses of the <it>Bunyaviridae </it>have segmented negative-stranded RNA genomes and several of them cause significant disease. Many partial sequences have been obtained from the segments so that GenBank searches give complex results. Sequence databases usually use HTML pages to mediate remote sorting, but this approach can be limiting and may discourage a user from exploring a database.</p> <p>Results</p> <p>The VirusBanker database contains <it>Bunyaviridae </it>sequences and alignments and is presented as two spreadsheets generated by a Java program that interacts with a MySQL database on a server. Sequences are displayed in rows and may be sorted using information that is displayed in columns and includes data relating to the segment, gene, protein, species, strain, sequence length, terminal sequence and date and country of isolation. <it>Bunyaviridae </it>sequences and alignments may be downloaded from the second spreadsheet with titles defined by the user from the columns, or viewed when passed directly to the sequence editor, Jalview.</p> <p>Conclusion</p> <p>VirusBanker allows large datasets of aligned nucleotide and protein sequences from the <it>Bunyaviridae </it>to be compiled and winnowed rapidly using criteria that are formulated heuristically.</p

Acute effects of nicotine on visual search tasks in young adult smokers

Rationale Nicotine is known to improve performance on tests involving sustained attention and recent research suggests that nicotine may also improve performance on tests involving the strategic allocation of attention and working memory. Objectives We used measures of accuracy and response latency combined with eye-tracking techniques to examine the effects of nicotine on visual search tasks. Methods In experiment 1 smokers and non-smokers performed pop-out and serial search tasks. In experiment 2, we used a within-subject design and a more demanding search task for multiple targets. In both studies, 2-h abstinent smokers were asked to smoke one of their own cigarettes between baseline and tests. Results In experiment 1, pop-out search times were faster after nicotine, without a loss in accuracy. Similar effects were observed for serial searches, but these were significant only at a trend level. In experiment 2, nicotine facilitated a strategic change in eye movements resulting in a higher proportion of fixations on target letters. If the cigarette was smoked on the first trial (when the task was novel), nicotine additionally reduced the total number of fixations and refixations on all letters in the display. Conclusions Nicotine improves visual search performance by speeding up search time and enabling a better focus of attention on task relevant items. This appears to reflect more efficient inhibition of eye movements towards task irrelevant stimuli, and better active maintenance of task goals. When the task is novel, and therefore more difficult, nicotine lessens the need to refixate previously seen letters, suggesting an improvement in working memory

Assessing Communities of Practice in health policy : A conceptual framework as a first step towards empirical research

Peer reviewe

Calcium Homeostasis in Myogenic Differentiation Factor 1 (MyoD)-Transformed, Virally-Transduced, Skin-Derived Equine Myotubes

Dysfunctional skeletal muscle calcium homeostasis plays a central role in the pathophysiology of several human and animal skeletal muscle disorders, in particular, genetic disorders associated with ryanodine receptor 1 (RYR1) mutations, such as malignant hyperthermia, central core disease, multiminicore disease and certain centronuclear myopathies. In addition, aberrant skeletal muscle calcium handling is believed to play a pivotal role in the highly prevalent disorder of Thoroughbred racehorses, known as Recurrent Exertional Rhabdomyolysis. Traditionally, such defects were studied in human and equine subjects by examining the contractile responses of biopsied muscle strips exposed to caffeine, a potent RYR1 agonist. However, this test is not widely available and, due to its invasive nature, is potentially less suitable for valuable animals in training or in the human paediatric setting. Furthermore, increasingly, RYR1 gene polymorphisms (of unknown pathogenicity and significance) are being identified through next generation sequencing projects. Consequently, we have investigated a less invasive test that can be used to study calcium homeostasis in cultured, skin-derived fibroblasts that are converted to the muscle lineage by viral transduction with a MyoD (myogenic differentiation 1) transgene. Similar models have been utilised to examine calcium homeostasis in human patient cells, however, to date, there has been no detailed assessment of the cells’ calcium homeostasis, and in particular, the responses to agonists and antagonists of RYR1. Here we describe experiments conducted to assess calcium handling of the cells and examine responses to treatment with dantrolene, a drug commonly used for prophylaxis of recurrent exertional rhabdomyolysis in horses and malignant hyperthermia in humans

Interventions for the control of Aedes aegypti in Latin America and the Caribbean: systematic review and meta-analysis

Objective: To determine the effectiveness and degree of implementation of interventions for the control of Aedes aegypti in Latin America and the Caribbean (LAC) as reported in scientific literature. Methods: We searched MEDLINE, EMBASE, CENTRAL, SOCINDEX, and LILACS, for experimental and observational studies, economic assessments and qualitative experiences carried out in LAC from 2000 to 2016. We assessed incidence and morbimortality of Aedes aegypti-related diseases and entomological indices: Breteau (containers), House, and Pupae per Person. We used GRADE methodology for assessing quality of evidence. Results: Of 1826 records retrieved, 75 were included and 9 cluster randomised clinical trials could be meta-analysed. We did not identify any intervention supported by a high certainty of evidence. In consistency with qualitative evidence, health education and community engagement probably reduces the entomological indices, as do the use of insecticide-treated materials, indoor residual spraying and the management of containers. There is low certainty of evidence supporting the use of ovitraps or larvitraps, and the integrated epidemiological surveillance strategy to improve indices and reduce the incidence of dengue. The reported degree of implementation of these vector control interventions was variable and most did not extend to whole cities and were not sustained beyond 2 years. Conclusions: We found a general lack of evidence on effectiveness of vector control in the region, despite a few interventions that showed moderate to low certainty of evidence. It is important to engage and educate the community, apart from achieving the implementation of integrated actions between the health and other sectors at national and regional level.Fil: Bardach, Ariel Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: García Perdomo, Herney Andrés. Universidad del Valle; ColombiaFil: Alcaraz, Andrea. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Tapia López, Elena. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Ruano Gandara, Ruth Amanda. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Ruvinsky, Silvina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Ciapponi, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; Argentin

Purinergic signaling microenvironments: An introduction

The common theme of this introductory article and the minireviews that follow in this special issue is the concept of microenvironments within tissues and surrounding cells that would be ideal signaling venues for a biologically active purinergic ligand. Collectively, the editors/authors and the other contributing authors agree that nucleotides and nucleosides would be most potent within a confined system. A talented cadre of purinergics has been solicited to discuss purinergic signaling in his or her favorite microenvironment within a given organ or tissue. We are gratified by the large number of original articles that also have successfully navigated the peer review process and are part of this special issue. These concepts are not simply purinergic, but the idea of maximal potency in a tissue microenvironment and surrounding specialized cells within a tissue pertains to any autacoid or paracrine agonist

EBV-gp350 Confers B-Cell Tropism to Tailored Exosomes and Is a Neo-Antigen in Normal and Malignant B Cells—A New Option for the Treatment of B-CLL

gp350, the major envelope protein of Epstein-Barr-Virus, confers B-cell tropism to the virus by interacting with the B lineage marker CD21. Here we utilize gp350 to generate tailored exosomes with an identical tropism. These exosomes can be used for the targeted co-transfer of functional proteins to normal and malignant human B cells. We demonstrate here the co-transfer of functional CD154 protein on tailored gp350+ exosomes to malignant B blasts from patients with B chronic lymphocytic leukemia (B-CLL), rendering B blasts immunogenic to tumor-reactive autologous T cells. Intriguingly, engulfment of gp350+ exosomes by B-CLL cells and presentation of gp350-derived peptides also re-stimulated EBV-specific T cells and redirected the strong antiviral cellular immune response in patients to leukemic B cells. In essence, we show that gp350 alone confers B-cell tropism to exosomes and that these exosomes can be further engineered to simultaneously trigger virus- and tumor-specific immune responses. The simultaneous exploitation of gp350 as a tropism molecule for tailored exosomes and as a neo-antigen in malignant B cells provides a novel attractive strategy for immunotherapy of B-CLL and other B-cell malignancies

How Do Galaxies Get Their Gas?

Not the way one might have thought. In hydrodynamic simulations of galaxy formation, some gas follows the traditionally envisioned route, shock heating to the halo virial temperature before cooling to the much lower temperature of the neutral ISM. But most gas enters galaxies without ever heating close to the virial temperature, gaining thermal energy from weak shocks and adiabatic compression, and radiating it just as quickly. This ``cold mode'' accretion is channeled along filaments, while the conventional, ``hot mode'' accretion is quasi-spherical. Cold mode accretion dominates high redshift growth by a substantial factor, while at z<1 the overall accretion rate declines and hot mode accretion has greater relative importance. The decline of the cosmic star formation rate at low z is driven largely by geometry, as the typical cross section of filaments begins to exceed that of the galaxies at their intersections.Comment: 7 pages, 1 figure. To be published in the proceedings of the IGM/Galaxy Connection- The Distribution of Baryons at z=0 conferenc