Pearl hunter : an inspired hyper-heuristic

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A hyper-heuristic inspired by pearl hunting

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Towards a learning-based heuristic searching reform scheme

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Pearl hunter: a cross-domain hyper-heuristic that compiles iterated local search algorithms

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H-alpha +[NII] Observations of the HII Regions in M81

In a first of a series of studies of the H-alpha + [NII] emission from nearby spiral galaxies, we present measurements of H-alpha + [NII] emission from HII regions in M81. Our method uses large-field-CCD images and long-slit spectra, and is part of the ongoing Beijing-Arizona-Taipei-Connecticut Sky Survey. The CCD images are taken with the NAOC 0.6/0.9m f/3 Schmidt telescope at the Xinglong Observing Station, using a multicolor filter set. Spectra of 10 of the brightest HII regions are obtained using the NAOC 2.16m telescope with a Tek 1024 X 1024 CCD. The continua of the spectra are calibrated by flux-calibrated images taken from the Schmidt observations. We determine the continuum component of our H-alpha + [NII] image via interpolation from the more accurately-measured backgrounds (M81 starlight) obtained from the two neighboring (in wavelength) BATC filter images. We use the calibrated fluxes of H-alpha + [NII] emission from the spectra to normalize this interpolated, continuum-subtracted H-alpha + [NII] image. We estimate the zero point uncertainty of the measured H-alpha + [NII] emission flux to be $\sim$ 8%. A catalogue of H-alpha + [NII] fluxes for 456 HII regions is provided, with those fluxes are on a more consistent linear scale than previously available. The logarithmically-binned H-alpha + [NII] luminosity function of HII regions is found to have slope $\alpha$ = -0.70, consistent with previous results (which allowed $\alpha=-0.5 \sim -0.8$). From the overall H-alpha + [NII] luminosity of the HII regions, the star formation rate of M81 is found to be $\sim 0.68 M_{\odot} {\rm yr}^{-1}$, modulo uncertainty with extinction corrections.Comment: 18 pages, 7 figures, accepted for publication in the Astronomical Journa

Disparities and risks of sexually transmissible infections among men who have sex with men in China: a meta-analysis and data synthesis.

BACKGROUND: Sexually transmitted infections (STIs), including Hepatitis B and C virus, are emerging public health risks in China, especially among men who have sex with men (MSM). This study aims to assess the magnitude and risks of STIs among Chinese MSM. METHODS: Chinese and English peer-reviewed articles were searched in five electronic databases from January 2000 to February 2013. Pooled prevalence estimates for each STI infection were calculated using meta-analysis. Infection risks of STIs in MSM, HIV-positive MSM and male sex workers (MSW) were obtained. This review followed the PRISMA guidelines and was registered in PROSPERO. RESULTS: Eighty-eight articles (11 in English and 77 in Chinese) investigating 35,203 MSM in 28 provinces were included in this review. The prevalence levels of STIs among MSM were 6.3% (95% CI: 3.5-11.0%) for chlamydia, 1.5% (0.7-2.9%) for genital wart, 1.9% (1.3-2.7%) for gonorrhoea, 8.9% (7.8-10.2%) for hepatitis B (HBV), 1.2% (1.0-1.6%) for hepatitis C (HCV), 66.3% (57.4-74.1%) for human papillomavirus (HPV), 10.6% (6.2-17.6%) for herpes simplex virus (HSV-2) and 4.3% (3.2-5.8%) for Ureaplasma urealyticum. HIV-positive MSM have consistently higher odds of all these infections than the broader MSM population. As a subgroup of MSM, MSW were 2.5 (1.4-4.7), 5.7 (2.7-12.3), and 2.2 (1.4-3.7) times more likely to be infected with chlamydia, gonorrhoea and HCV than the broader MSM population, respectively. CONCLUSION: Prevalence levels of STIs among MSW were significantly higher than the broader MSM population. Co-infection of HIV and STIs were prevalent among Chinese MSM. Integration of HIV and STIs healthcare and surveillance systems is essential in providing effective HIV/STIs preventive measures and treatments. TRIAL REGISTRATION: PROSPERO NO: CRD42013003721

The prevalence and risk of metabolic syndrome and its components among people with posttraumatic stress disorder: A systematic review and meta-analysis

Objective: People with posttraumatic stress disorder (PTSD) have a higher mortality than the general population, mainly due to cardiovascular diseases (CVD). Metabolic syndrome (MetS) and its components are highly predictive of CVD. The aim of this meta-analysis was to describe pooled frequencies of MetS and its components in people with PTSD and to compare MetS prevalences in PTSD versus the general population. Method: Medline, PsycARTICLES, Embase and CINAHL were searched until 02/2015 for cross-sectional and baseline data of longitudinal studies in adults with PTSD. Two independent reviewers conducted the searches and extracted data. Random effects meta-analysis with a relative risk, subgroups and meta-regression analyses were employed. Results: Overall, 9 studies met the inclusion criteria including 9,254 individuals in midlife with PTSD and 6,852 general population controls. The pooled MetS prevalence was 38.7% (95%CI = 32.1%-45.6%; Q = 52.1, p < 0.001; N = 9; n = 9,673; age range = 44-61years). Abdominal obesity was observed in 49.3% (95%CI = 29.7%-69.0%), hyperglycaemia in 36.1% (95%CI = 18.8%-55.6%), hypertriglyceridemia in 45.9% (95%CI = 12.2%-81.9%), low high density-lipoprotein-cholesterol in 46.4% (95%CI = 26.4%-67.0%) and hypertension in 76.9% (95%CI = 67.9%-84.8). The MetS prevalence was consistently high across geographical regions, settings or populations (war veterans or not). Compared with matched general population controls, people with PTSD had an almost double increased risk for MetS (RR = 1.82; 95%CI = 1.72-1.92; p < 0.001). Most analyses were not statistically heterogeneous. Conclusions: MetS is highly prevalent in people with PTSD. Routine screening and multidisciplinary management of medical and behavioral conditions is needed. Future research should focus on how cardio-metabolic outcomes are moderated by clinical and treatment characteristics and genetic factors

Structural and Mutational Analysis of Functional Differentiation between Synaptotagmins-1 and -7

Synaptotagmins are known to mediate diverse forms of Ca2+-triggered exocytosis through their C2 domains, but the principles underlying functional differentiation among them are unclear. Synaptotagmin-1 functions as a Ca2+ sensor in neurotransmitter release at central nervous system synapses, but synaptotagmin-7 does not, and yet both isoforms act as Ca2+ sensors in chromaffin cells. To shed light into this apparent paradox, we have performed rescue experiments in neurons from synaptotagmin-1 knockout mice using a chimera that contains the synaptotagmin-1 sequence with its C2B domain replaced by the synaptotagmin-7 C2B domain (Syt1/7). Rescue was not achieved either with the WT Syt1/7 chimera or with nine mutants where residues that are distinct in synaptotagmin-7 were restored to those present in synaptotagmin-1. To investigate whether these results arise because of unique conformational features of the synaptotagmin-7 C2B domain, we determined its crystal structure at 1.44 Å resolution. The synaptotagmin-7 C2B domain structure is very similar to that of the synaptotagmin-1 C2B domain and contains three Ca2+-binding sites. Two of the Ca2+-binding sites of the synaptotagmin-7 C2B domain are also present in the synaptotagmin-1 C2B domain and have analogous ligands to those determined for the latter by NMR spectroscopy, suggesting that a discrepancy observed in a crystal structure of the synaptotagmin-1 C2B domain arose from crystal contacts. Overall, our results suggest that functional differentiation in synaptotagmins arises in part from subtle sequence changes that yield dramatic functional differences