726 research outputs found

    Neurospora from natural populations: Population genomics insights into the Life history of a model microbial Eukaryote

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    The ascomycete filamentous fungus Neurospora crassa played a historic role in experimental biology and became a model system for genetic research. Stimulated by a systematic effort to collect wild strains initiated by Stanford geneticist David Perkins, the genus Neurospora has also become a basic model for the study of evolutionary processes, speciation, and population biology. In this chapter, we will first trace the history that brought Neurospora into the era of population genomics. We will then cover the major contributions of population genomic investigations using Neurospora to our understanding of microbial biogeography and speciation, and review recent work using population genomics and genome-wide association mapping that illustrates the unique potential of Neurospora as a model for identifying the genetic basis of (potentially adaptive) phenotypes in filamentous fungi. The advent of population genomics has contributed to firmly establish Neurospora as a complete model system and we hope our review will entice biologists to include Neurospora in their research

    Semianalytical Universal Simulation of the Electrical Properties of the Permeable Base Transistor

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    Using only a few numerical calculations, we give the analytical current-voltage and charge-voltage characteristics valid for any PBT. The highest unity current gain frequency (f,) corresponding to the current technology is on the order of 30 GHz; nevertheless, the oscillation frequency can be higher than 100 GHz. 1

    Human bite injuries in the oro-facial region at the Muhimbili National Hospital, Tanzania

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    <p>Abstract</p> <p>Background</p> <p>Human bites in the maxillofacial region compromise function and aesthetics, resulting in social and psychological effects. There is paucity of information regarding human bite injuries in Tanzania. The aim of the study was to assess the occurrence, treatment modalities and prognosis of human bite injuries in the oro-facial region at the Muhimbili National Hospital Dar es Salaam, Tanzania.</p> <p>Methods</p> <p>In a prospective study the details of patients with human bite injuries in the oro-facial region who attended at the Department of Oral and Maxillofacial Surgery of the Muhimbili National Hospital between January 2001 and December 2005 were recorded. Data included information on age, sex, site, duration of the injury at the time of reporting to hospital, reasons, details of treatment offered and outcome after treatment.</p> <p>Results</p> <p>A total of 33 patients, 13 males and 20 females aged between 12 and 49 years with human bite injuries in the oro-facial region were treated. Thirty patients presented with clean uninfected wounds while 3 had infected wounds. The most (45.5%) frequently affected site was the lower lip. Treatment offered included thorough surgical cleansing with adequate surgical debridement and primary suturing. Tetanus prophylaxis and a course of broad-spectrum antibiotics were given to all the patients. In 90% of the 30 patients who were treated by suturing, the healing was uneventful with only 10% experiencing wound infection or necrosis. Three patients who presented with wounds that had signs of infection were treated by surgical cleansing with debridement, antibiotics and daily dressing followed by delayed primary suturing.</p> <p>Conclusion</p> <p>Most of the human bite injuries in the oro-facial region were due to social conflicts. Although generally considered to be dirty or contaminated they could be successfully treated by surgical cleansing and primary suture with a favourable outcome. Management of such injuries often need multidisciplinary approach.</p

    Up-to-date on mortality in COPD - report from the OLIN COPD study

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    <p>Abstract</p> <p>Background</p> <p>The poor recognition and related underdiagnosis of COPD contributes to an underestimation of mortality in subjects with COPD. Data derived from population studies can advance our understanding of the true burden of COPD. The objective of this report was to evaluate the impact of COPD on mortality and its predictors in a cohort of subjects with and without COPD recruited during the twenty first century.</p> <p>Methods</p> <p>All subjects with COPD (n = 993) defined according to the GOLD spirometric criteria, FEV<sub>1</sub>/FVC < 0.70, and gender- and age-matched subjects without airway obstruction, non-COPD (n = 993), were identified in a clinical follow-up survey of the Obstructive Lung Disease in Northern Sweden (OLIN) Studies cohorts in 2002-2004. Mortality was observed until the end of year 2007. Baseline data from examination at recruitment were used in the risk factor analyses; age, smoking status, lung function (FEV<sub>1 </sub>% predicted) and reported heart disease.</p> <p>Results</p> <p>The mortality was significantly higher among subjects with COPD, 10.9%, compared to subjects without COPD, 5.8% (p < 0.001). Mortality was associated with higher age, being a current smoker, male gender, and COPD. Replacing COPD with FEV<sub>1 </sub>% predicted in the multivariate model resulted in the decreasing level of FEV<sub>1 </sub>being a significant risk factor for death, while heart disease was not a significant risk factor for death in any of the models.</p> <p>Conclusions</p> <p>In this cohort COPD and decreased FEV<sub>1 </sub>were significant risk factors for death when adjusted for age, gender, smoking habits and reported heart disease.</p

    Study design and participant characteristics of a randomized controlled trial of directly administered antiretroviral therapy in opioid treatment programs

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    <p>Abstract</p> <p>Background</p> <p>HIV-infected drug users are at higher risk of non-adherence and poor treatment outcomes than HIV-infected non-drug users. Prior work from our group and others suggests that directly administered antiretroviral therapy (DAART) delivered in opioid treatment programs (OTPs) may increase rates of viral suppression.</p> <p>Methods/Design</p> <p>We are conducting a randomized trial comparing DAART to self-administered therapy (SAT) in 5 OTPs in Baltimore, Maryland. Participants and investigators are aware of treatment assignments. The DAART intervention is 12 months. The primary outcome is HIV RNA < 50 copies/mL at 3, 6, and 12 months. To assess persistence of any study arm differences that emerge during the active intervention, we are conducting an 18-month visit (6 months after the intervention concludes). We are collecting electronic adherence data for 2 months in both study arms. Of 457 individuals screened, a total of 107 participants were enrolled, with 56 and 51 randomly assigned to DAART and SAT, respectively. Participants were predominantly African American, approximately half were women, and the median age was 47 years. Active use of cocaine and other drugs was common at baseline. HIV disease stage was advanced in most participants. The median CD4 count at enrollment was 207 cells/mm<sup>3</sup>, 66 (62%) had a history of an AIDS-defining opportunistic condition, and 21 (20%) were antiretroviral naïve.</p> <p>Conclusions</p> <p>This paper describes the rationale, methods, and baseline characteristics of subjects enrolled in a randomized clinical trial comparing DAART to SAT in opioid treatment programs.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00279110">NCT00279110</a></p

    Two-pion Bose-Einstein correlations in central Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

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    The first measurement of two-pion Bose-Einstein correlations in central Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.Comment: 17 pages, 5 captioned figures, 1 table, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/388

    Beauty photoproduction measured using decays into muons in dijet events in ep collisions at s\sqrt{s}=318 GeV

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    The photoproduction of beauty quarks in events with two jets and a muon has been measured with the ZEUS detector at HERA using an integrated luminosity of 110 pb1^{- 1}. The fraction of jets containing b quarks was extracted from the transverse momentum distribution of the muon relative to the closest jet. Differential cross sections for beauty production as a function of the transverse momentum and pseudorapidity of the muon, of the associated jet and of xγjetsx_{\gamma}^{jets}, the fraction of the photon's momentum participating in the hard process, are compared with MC models and QCD predictions made at next-to-leading order. The latter give a good description of the data.Comment: 32 pages, 6 tables, 7 figures Table 6 and Figure 7 revised September 200
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