12,690 research outputs found

    Why I support Open Access

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    I would like to see all scholars enjoy open access to all research information, regardless of their educational background, affiliation, nationality, or financial status. People working for the betterment of humanity should be supported with resources, and not discriminated against. I would like to see all children who are curious about science, arts, humanities, and engineering, be able to choose to learn from freely available peer-reviewed journal articles, and not just from social media posts. I would like to see open access in research will not only be made free for readers, but also free for researchers who are publishing their research, so that the funds that are not used for publishing, can be allocated to research training, education, & research infrastructure. I would like to see all scholars support open access in research, as knowledge kept within paid walls serves only a selected few, while open access knowledge serves many

    Affleck-Dine Baryogenesis, Split Supersymmetry, and Inflation

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    It is shown that, in the context of split supersymmetry, a simple model with a single complex scalar field can produce chaotic inflation and generate the observed amount of baryon asymmetry via the Affleck-Dine mechanism. While the inflaton quantum fluctuations give rise to curvature perturbation, we show that quantum fluctuations of the phase of the scalar field can produce baryonic isocurvature perturbation. Combining with constraints from WMAP data, all parameters in the model can be determined to within a narrow range.Comment: version accepted for publication in PR

    Temporal and spatial variation in the morphology of the brown macroalga Hormosira banksii (Fucales, Phaeophyta)

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    Hormosira banksii is a morphologically variable macroalgal species from southeastern and southern Australia, which has been previously categorised into ecoforms according to habitat. This study is by far the largest quantitative evaluation of morphological variation in H. banksii, covering 74 sites from South Australia, Victoria, New South Wales and Tasmania. Morphological features from 505 samples were analysed using principal components analysis, with the patterns identified being statistically assessed with a Monte Carlo permutation test. There was considerable morphological variation between samples taken at several marine (but not estuarine) sites in both 1994 and 1999. However, this variation was not consistent across either morphological features or populations, and presumably represents random fluctuations. Analysis of the entire dataset demonstrated a significant difference between samples growing in marine and estuarine habitats. Further assessment of variation within these two groups revealed some significantly different populations based on geographical locations but not habitat variation. While this study presents strong evidence for two distinct taxa within H. banksii (marine versus estuarine populations), the taxonomic status of this species should not be altered until genetic studies have been conducted. © 2005 by Walter de Gruyter

    Prokineticin 2 Is a Target Gene of Proneural Basic Helix-Loop-Helix Factors for Olfactory Bulb Neurogenesis

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    Prokineticin 2, a cysteine-rich secreted protein, regulates diverse biological functions including the neurogenesis of olfactory bulb. Here we show that the PK2 gene is a functional target gene of proneural basic helix-loop-helix (bHLH) factors. Neurogenin 1 and MASH1 activate PK2 transcription by binding to E-box motifs on the PK2 promoter with the same set of E-boxes critical for another pair of bHLH factors, CLOCK and BMAL1, in the regulation of circadian clock. Our results establish PK2 as a common functional target gene for different bHLH transcriptional factors in mediating their respective functions

    Bronchodilators for the prevention and treatment of chronic lung disease in preterm infants

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    Background: Chronic lung disease (CLD) occurs frequently in preterm infants. Bronchodilators have the potential effect of dilating small airways with muscle hypertrophy. Increased compliance and tidal volume and decreased pulmonary resistance have been documented with the use of bronchodilators in infants with CLD. Therefore, bronchodilators might have a role in the prevention and treatment of CLD. Objectives: To determine the effect of bronchodilators given as prophylaxis or as treatment for CLD on mortality and other complications of preterm birth in infants at risk for or identified as having CLD. Search methods: On 2016 March 7, we used the standard strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 2), MEDLINE (from 1966), Embase (from 1980) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; from 1982). We searched clinical trials databases, conference proceedings and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. We applied no language restrictions. Selection criteria: Randomised and quasi-randomised controlled trials involving preterm infants were eligible for inclusion. Initiation of bronchodilator therapy for prevention of CLD had to occur within two weeks of birth. Treatment of patients with CLD had to be initiated before discharge from the neonatal unit. The intervention had to include administration of a bronchodilator by nebulisation, by metered dose inhaler (with or without a spacer device) or by intravenous or oral administration versus placebo or no intervention. Eligible studies had to include at least one of the following predefined clinical outcomes: mortality, CLD, number of days on oxygen, number of days on ventilator, patent ductus arteriosus (PDA), pulmonary interstitial emphysema (PIE), pneumothorax, intraventricular haemorrhage (IVH) of any grade, necrotising enterocolitis (NEC), sepsis and adverse effects of bronchodilators. Data collection and analysis: We used the standard method described in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). Two review authors extracted and assessed all data provided by each study. We reported risk ratio (RR), risk difference (RD) and number needed to treat for an additional beneficial outcome (NNTB) with 95% confidence interval (CI) for dichotomous outcomes and mean difference (MD) for continuous data. We assessed the quality of the evidence by using the GRADE approach. Main results: For this update, we identified one new randomised controlled trial investigating effects of bronchodilators in preterm infants. This study, which enrolled 73 infants but reported on 52 infants, examined prevention of CLD with the use of aminophylline. According to GRADE, the quality of the evidence was very low. One previously included study enrolled 173 infants to look at prevention of CLD with the use of salbutamol. According to GRADE, the quality of the evidence was moderate. We found no eligible trial that studied the use of bronchodilator therapy for treatment of individuals with CLD. Prophylaxis with salbutamol led to no statistically significant differences in mortality (RR 1.08, 95% CI 0.50 to 2.31; RD 0.01, 95% CI -0.09 to 0.11) nor in CLD (RR 1.03, 95% CI 0.78 to 1.37; RD 0.02, 95% CI -0.13 to 0.17). Results showed no statistically significant differences in other complications associated with CLD nor in preterm birth. Investigators in this study did not comment on side effects due to salbutamol. Prophylaxis with aminophylline led to a significant reduction in CLD at 28 days of life (RR 0.18, 95% CI 0.04 to 0.74; RD -0.35, 95% CI -0.56 to -0.13; NNTB 3, 95% CI 2 to 8) and no significant difference in mortality (RR 3.0, 95% CI 0.33 to 26.99; RD 0.08, 95% CI -0.07 to 0.22), along with a significantly shorter dependency on supplementary oxygen in the aminophylline group compared with the no treatment group (MD -17.75 days, 95% CI -27.56 to -7.94). Tests for heterogeneity were not applicable for any of the analyses, as each meta-analysis included only one study. Authors\u27 conclusions: Data are insufficient for reliable assessment of the use of salbutamol for prevention of CLD. One trial of poor quality reported a reduction in the incidence of CLD and shorter duration of supplementary oxygen with prophylactic aminophylline, but these results must be interpreted with caution. Additional clinical trials are necessary to assess the role of bronchodilator agents in prophylaxis or treatment of CLD. Researchers studying the effects of bronchodilators in preterm infants should include relevant clinical outcomes in addition to pulmonary mechanical outcomes. We identified no trials that studied the use of bronchodilator therapy for treatment of CLD
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