| 1. |
- Ademuyiwa, Adesoji O., et al.
(författare)
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Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
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Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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| 2. |
- Anney, Richard, et al.
(författare)
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A genome-wide scan for common alleles affecting risk for autism.
- 2010
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 19:20, s. 4072-4082
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Tidskriftsartikel (refereegranskat)abstract
- Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10(-8). When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10(-8) threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C.
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| 3. |
- Anney, Richard, et al.
(författare)
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Individual common variants exert weak effects on the risk for autism spectrum disorders.
- 2012
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 21:21, s. 4781-92
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Tidskriftsartikel (refereegranskat)abstract
- While it is apparent that rare variation can play an important role in the genetic architecture of autism spectrum disorders (ASD), the contribution of common variation to ASD risk is less clear. To produce a more comprehensive picture, we report Stage 2 of the Autism Genome Project genome-wide association study, adding 1301 ASD families and bringing the total to 2705 families analysed (Stages 1 and 2). In addition to evaluating association of individual SNPs, we also sought evidence that common variants, en masse, might affect risk. Despite genotyping over a million SNPs covering the genome, no single SNP shows significant association with ASD or selected phenotypes at a genome-wide level. The SNP that achieves the smallest p-value from secondary analyses is rs1718101. It falls in CNTNAP2, a gene previously implicated in susceptibility for ASD. This SNP also shows modest association with age of word/phrase acquisition in ASD subjects, of interest because features of language development are also associated with other variation in CNTNAP2. By contrast, allele-scores derived from the transmission of common alleles to Stage 1 cases significantly predict case-status in the independent Stage 2 sample. Despite being significant, the variance explained by these allele scores was small (Vm< 1%). Based on results from individual SNPs and their en masse effect on risk, as inferred from the allele-score results, it is reasonable to conclude that common variants affect ASD risk but their individual effects are modest.
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| 4. |
- Casey, Jillian P, et al.
(författare)
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A novel approach of homozygous haplotype sharing identifies candidate genes in autism spectrum disorder.
- 2012
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Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 131:4, s. 565-579
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Tidskriftsartikel (refereegranskat)abstract
- Autism spectrum disorder (ASD) is a highly heritable disorder of complex and heterogeneous aetiology. It is primarily characterized by altered cognitive ability including impaired language and communication skills and fundamental deficits in social reciprocity. Despite some notable successes in neuropsychiatric genetics, overall, the high heritability of ASD (~90%) remains poorly explained by common genetic risk variants. However, recent studies suggest that rare genomic variation, in particular copy number variation, may account for a significant proportion of the genetic basis of ASD. We present a large scale analysis to identify candidate genes which may contain low-frequency recessive variation contributing to ASD while taking into account the potential contribution of population differences to the genetic heterogeneity of ASD. Our strategy, homozygous haplotype (HH) mapping, aims to detect homozygous segments of identical haplotype structure that are shared at a higher frequency amongst ASD patients compared to parental controls. The analysis was performed on 1,402 Autism Genome Project trios genotyped for 1 million single nucleotide polymorphisms (SNPs). We identified 25 known and 1,218 novel ASD candidate genes in the discovery analysis including CADM2, ABHD14A, CHRFAM7A, GRIK2, GRM3, EPHA3, FGF10, KCND2, PDZK1, IMMP2L and FOXP2. Furthermore, 10 of the previously reported ASD genes and 300 of the novel candidates identified in the discovery analysis were replicated in an independent sample of 1,182 trios. Our results demonstrate that regions of HH are significantly enriched for previously reported ASD candidate genes and the observed association is independent of gene size (odds ratio 2.10). Our findings highlight the applicability of HH mapping in complex disorders such as ASD and offer an alternative approach to the analysis of genome-wide association data.
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| 5. |
- Pinto, Dalila, et al.
(författare)
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Convergence of Genes and Cellular Pathways Dysregulated in Autism Spectrum Disorders.
- 2014
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Ingår i: American journal of human genetics. - : Elsevier BV. - 1537-6605 .- 0002-9297. ; 94:5, s. 677-694
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Tidskriftsartikel (refereegranskat)abstract
- Rare copy-number variation (CNV) is an important source of risk for autism spectrum disorders (ASDs). We analyzed 2,446 ASD-affected families and confirmed an excess of genic deletions and duplications in affected versus control groups (1.41-fold, p = 1.0× 10(-5)) and an increase in affected subjects carrying exonic pathogenic CNVs overlapping known loci associated with dominant or X-linked ASD and intellectual disability (odds ratio = 12.62, p = 2.7× 10(-15), ∼3% of ASD subjects). Pathogenic CNVs, often showing variable expressivity, included rare de novo and inherited events at 36 loci, implicating ASD-associated genes (CHD2, HDAC4, and GDI1) previously linked to other neurodevelopmental disorders, as well as other genes such as SETD5, MIR137, and HDAC9. Consistent with hypothesized gender-specific modulators, females with ASD were more likely to have highly penetrant CNVs (p = 0.017) and were also overrepresented among subjects with fragile X syndrome protein targets (p = 0.02). Genes affected by de novo CNVs and/or loss-of-function single-nucleotide variants converged on networks related to neuronal signaling and development, synapse function, and chromatin regulation.
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| 6. |
- Pinto, Dalila, et al.
(författare)
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Functional impact of global rare copy number variation in autism spectrum disorders.
- 2010
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 466:7304, s. 368-372
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Tidskriftsartikel (refereegranskat)abstract
- The autism spectrum disorders (ASDs) are a group of conditions characterized by impairments in reciprocal social interaction and communication, and the presence of restricted and repetitive behaviours. Individuals with an ASD vary greatly in cognitive development, which can range from above average to intellectual disability. Although ASDs are known to be highly heritable ( approximately 90%), the underlying genetic determinants are still largely unknown. Here we analysed the genome-wide characteristics of rare (<1% frequency) copy number variation in ASD using dense genotyping arrays. When comparing 996 ASD individuals of European ancestry to 1,287 matched controls, cases were found to carry a higher global burden of rare, genic copy number variants (CNVs) (1.19 fold, P = 0.012), especially so for loci previously implicated in either ASD and/or intellectual disability (1.69 fold, P = 3.4 x 10(-4)). Among the CNVs there were numerous de novo and inherited events, sometimes in combination in a given family, implicating many novel ASD genes such as SHANK2, SYNGAP1, DLGAP2 and the X-linked DDX53-PTCHD1 locus. We also discovered an enrichment of CNVs disrupting functional gene sets involved in cellular proliferation, projection and motility, and GTPase/Ras signalling. Our results reveal many new genetic and functional targets in ASD that may lead to final connected pathways.
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| 7. |
- Abolfathi, Bela, et al.
(författare)
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The Fourteenth Data Release of the Sloan Digital Sky Survey : First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
- 2018
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Ingår i: Astrophysical Journal Supplement Series. - : IOP Publishing Ltd. - 0067-0049 .- 1538-4365. ; 235:2
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Tidskriftsartikel (refereegranskat)abstract
- The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.
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| 8. |
- Blanton, Michael R., et al.
(författare)
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Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
- 2017
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Ingår i: Astronomical Journal. - : IOP Publishing Ltd. - 0004-6256 .- 1538-3881. ; 154:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and. high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z similar to 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z similar to 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs. and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the. Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.
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| 9. |
- Crowther-Swanepoel, Dalemari, et al.
(författare)
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Common variants at 2q37.3, 8q24.21, 15q21.3 and 16q24.1 influence chronic lymphocytic leukemia risk
- 2010
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:2, s. 132-136
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Tidskriftsartikel (refereegranskat)abstract
- To identify new risk variants for chronic lymphocytic leukemia (CLL), we conducted a genome-wide association study of 299,983 tagging SNPs, with validation in four additional series totaling 2,503 cases and 5,789 controls. We identified four new risk loci for CLL at 2q37.3 (rs757978, FARP2; odds ratio (OR) = 1.39; P = 2.11 x 10(-9)), 8q24.21 (rs2456449; OR = 1.26; P = 7.84 x 10(-10)), 15q21.3 (rs7169431; OR = 1.36; P = 4.74 x 10(-7)) and 16q24.1 (rs305061; OR = 1.22; P = 3.60 x 10(-7)). We also found evidence for risk loci at 15q25.2 (rs783540, CPEB1; OR = 1.18; P = 3.67 x 10(-6)) and 18q21.1 (rs1036935; OR = 1.22; P = 2.28 x 10(-6)). These data provide further evidence for genetic susceptibility to this B-cell hematological malignancy.
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| 10. |
- Schael, S., et al.
(författare)
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Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
- 2013
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
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Forskningsöversikt (refereegranskat)abstract
- Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma - 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019. (C) 2013 Elsevier B.V. All rights reserved.
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| 11. |
- Speedy, Helen E., et al.
(författare)
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A genome-wide association study identifies multiple susceptibility loci for chronic lymphocytic leukemia
- 2014
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 46:1, s. 56-
-
Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) of chronic lymphocytic leukemia (CLL) have shown that common genetic variation contributes to the heritable risk of CLL. To identify additional CLL susceptibility loci, we conducted a GWAS and performed a meta-analysis with a published GWAS totaling 1,739 individuals with CLL (cases) and 5,199 controls with validation in an additional 1,144 cases and 3,151 controls. A combined analysis identified new susceptibility loci mapping to 3q26.2 (rs10936599, P = 1.74 x 10(-9)), 4q26 (rs6858698, P = 3.07 x 10(-9)), 6q25.2 (IPCEF1, rs2236256, P = 1.50 x 10(-10)) and 7q31.33 (POT1, rs17246404, P = 3.40 x 10(-8)). Additionally, we identified a promising association at 5p15.33 (CLPTM1L, rs31490, P = 1.72 x 10(-7)) and validated recently reported putative associations at 5p15.33 (TERT, rs10069690, P = 1.12 x 10(-10)) and 8q22.3 (rs2511714, P = 2.90 x 10(-9)). These findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CLL.
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| 12. |
- Sumaila, U. Rashid, et al.
(författare)
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WTO must ban harmful fisheries subsidies
- 2021
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 374:6567, s. 544-544
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 13. |
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| 26. |
- Adie, Bailey Ashton, et al.
(författare)
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Careers, citations, bibliometrics, and impact : perspectives of new and emerging researchers
- 2024
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Ingår i: How to get published in the best tourism journals. - Cheltenham : Edward Elgar Publishing. - 9781035300600 - 9781035300594 ; , s. 211-238
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Bokkapitel (refereegranskat)abstract
- This chapter brings together invited contributions from new and emerging academics with respect to their experiences and how publishing demands affect their careers and life, and vice versa. The provision of such experiences is important as it conveys the reality of publishing from a real-world context with respect to the pressures we face, especially when starting on the academic ladder. Authors were given a broad scope with respect to their contributions and the results are provided with only very minor editing. They have also been presented anonymously, or rather collectively, because although there are clearly different perspectives, emphasises, and interpretations, there are also commonalities in the contributors’ experiences. Nevertheless, as the reader will see, there are a number of common themes that emerge. Following the perspectives of the different contributions the chapter will discuss some of the main issues that emerge and their implications, including some of the darker aspects of the pressures of publishing.
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| 27. |
- Alvesson, Mats, et al.
(författare)
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Qualitative Interview
- 2008
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Ingår i: International Encyclopedia of Organization Studies. - 1412956242 ; , s. 1342-1344
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 28. |
- Aronson, Richard, et al.
(författare)
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No barrier to emergence of bathyal king crabs on the Antarctic shelf
- 2015
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Ingår i: Proceedings of the National Academy of Science of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 112:42, s. 12997-13002
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Tidskriftsartikel (refereegranskat)abstract
- Cold-water conditions have excluded durophagous (skeleton-breaking) predators from the Antarctic seafloor for millions of years. Rapidly warming seas off the western Antarctic Peninsula could now facilitate their return to the continental shelf, with profound consequences for the endemic fauna. Among the likely first arrivals are king crabs (Lithodidae), which were discovered recently on the adjacent continental slope. During the austral summer of 2010‒2011, we used underwater imagery to survey a slope-dwelling population of the lithodid Paralomis birsteini off Marguerite Bay, western Antarctic Peninsula for environmental or trophic impediments to shoreward expansion. The population density averaged ∼4.5 individuals × 1,000 m−2 within a depth range of 1,100‒1,500 m (overall observed depth range 841–2,266 m). Images of juveniles, discarded molts, and precopulatory behavior, as well as gravid females in a trapping study, suggested a reproductively viable population on the slope. At the time of the survey, there was no thermal barrier to prevent the lithodids from expanding upward and emerging on the outer shelf (400- to 550-m depth); however, near-surface temperatures remained too cold for them to survive in inner-shelf and coastal environments (<200 m). Ambient salinity, composition of the substrate, and the depth distribution of potential predators likewise indicated no barriers to expansion of lithodids onto the outer shelf. Primary food resources for lithodids—echinoderms and mollusks—were abundant on the upper slope (550–800 m) and outer shelf. As sea temperatures continue to rise, lithodids will likely play an increasingly important role in the trophic structure of subtidal communities closer to shore.
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| 29. |
- Bailey, Richard, et al.
(författare)
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Host Niches and Defensive Extended Phenotypes Structure Parasitoid Wasp Communities
- 2009
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Ingår i: PLoS biology. - : Public Library of Science (PLoS). - 1544-9173 .- 1545-7885. ; 7:8, s. e1000179-
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Tidskriftsartikel (refereegranskat)abstract
- Oak galls are spectacular extended phenotypes of gallwasp genes in host oak tissues and have evolved complex morphologies that serve, in part, to exclude parasitoid natural enemies. Parasitoids and their insect herbivore hosts have coevolved to produce diverse communities comprising about a third of all animal species. The factors structuring these communities, however, remain poorly understood. An emerging theme in community ecology is the need to consider the effects of host traits, shaped by both natural selection and phylogenetic history, on associated communities of natural enemies. Here we examine the impact of host traits and phylogenetic relatedness on 48 ecologically closed and species-rich communities of parasitoids attacking gall-inducing wasps on oaks. Gallwasps induce the development of spectacular and structurally complex galls whose species- and generation-specific morphologies are the extended phenotypes of gallwasp genes. All the associated natural enemies attack their concealed hosts through gall tissues, and several structural gall traits have been shown to enhance defence against parasitoid attack. Here we explore the significance of these and other host traits in predicting variation in parasitoid community structure across gallwasp species. In particular, we test the "Enemy Hypothesis,'' which predicts that galls with similar morphology will exclude similar sets of parasitoids and therefore have similar parasitoid communities. Having controlled for phylogenetic patterning in host traits and communities, we found significant correlations between parasitoid community structure and several gall structural traits (toughness, hairiness, stickiness), supporting the Enemy Hypothesis. Parasitoid community structure was also consistently predicted by components of the hosts' spatiotemporal niche, particularly host oak taxonomy and gall location (e.g., leaf versus bud versus seed). The combined explanatory power of structural and spatiotemporal traits on community structure can be high, reaching 62% in one analysis. The observed patterns derive mainly from partial niche specialisation of highly generalist parasitoids with broad host ranges (>20 hosts), rather than strict separation of enemies with narrower host ranges, and so may contribute to maintenance of the richness of generalist parasitoids in gallwasp communities. Though evolutionary escape from parasitoids might most effectively be achieved via changes in host oak taxon, extreme conservatism in this trait for gallwasps suggests that selection is more likely to have acted on gall morphology and location. Any escape from parasitoids associated with evolutionary shifts in these traits has probably only been transient, however, due to subsequent recruitment of parasitoid species already attacking other host galls with similar trait combinations.
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| 30. |
- Bailey, Richard I., et al.
(författare)
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Female Drosophila melanogaster Gene Expression and Mate Choice : The X Chromosome Harbours Candidate Genes Underlying Sexual Isolation
- 2011
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:2, s. e17358-
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Tidskriftsartikel (refereegranskat)abstract
- Background: The evolution of female choice mechanisms favouring males of their own kind is considered a crucial step during the early stages of speciation. However, although the genomics of mate choice may influence both the likelihood and speed of speciation, the identity and location of genes underlying assortative mating remain largely unknown. Methods and Findings: We used mate choice experiments and gene expression analysis of female Drosophila melanogaster to examine three key components influencing speciation. We show that the 1,498 genes in Zimbabwean female D. melanogaster whose expression levels differ when mating with more (Zimbabwean) versus less (Cosmopolitan strain) preferred males include many with high expression in the central nervous system and ovaries, are disproportionately X-linked and form a number of clusters with low recombination distance. Significant involvement of the brain and ovaries is consistent with the action of a combination of pre- and postcopulatory female choice mechanisms, while sex linkage and clustering of genes lead to high potential evolutionary rate and sheltering against the homogenizing effects of gene exchange between populations. Conclusion: Taken together our results imply favourable genomic conditions for the evolution of reproductive isolation through mate choice in Zimbabwean D. melanogaster and suggest that mate choice may, in general, act as an even more important engine of speciation than previously realized.
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| 31. |
- Bellomo, Rinaldo, et al.
(författare)
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A controlled trial of electronic automated advisory vital signs monitoring in general hospital wards*
- 2012
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Ingår i: Critical Care Medicine. - 1530-0293. ; 40:8, s. 2349-2361
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Deteriorating ward patients are at increased risk. Electronic automated advisory vital signs monitors may help identify such patients and improve their outcomes. SETTING: A total of 349 beds, in 12 general wards in ten hospitals in the United States, Europe, and Australia. PATIENTS: Cohort of 18,305 patients. DESIGN: Before-and-after controlled trial. INTERVENTION: We deployed electronic automated advisory vital signs monitors to assist in the acquisition of vital signs and calculation of early warning scores. We assessed their effect on frequency, type, and treatment of rapid response team calls; survival to hospital discharge or to 90 days for rapid response team call patients; overall type and number of serious adverse events and length of hospital stay. MEASUREMENTS AND MAIN RESULTS: We studied 9,617 patients before (control) and 8,688 after (intervention) deployment of electronic automated advisory vital signs monitors. Among rapid response team call patients, intervention was associated with an increased proportion of calls secondary to abnormal respiratory vital signs (from 21% to 31%; difference [95% confidence interval] 9.9 [0.1-18.5]; p = .029). Survival immediately after rapid response team treatment and survival to hospital discharge or 90 days increased from 86% to 92% (difference [95% confidence interval] 6.3 [0.0-12.6]; p = .04). Intervention was also associated with a decrease in median length of hospital stay in all patients (unadjusted p < .0001; adjusted p = .09) and more so in U.S. patients (from 3.4 to 3.0 days; unadjusted p < .0001; adjusted ratio [95% confidence interval] 1.03 [1.00-1.06]; p = .026). The time required to complete and record a set of vital signs decreased from 4.1 ± 1.3 mins to 2.5 ± 0.5 mins (difference [95% confidence interval] 1.6 [1.4-1.8]; p < .0001). CONCLUSIONS: Deployment of electronic automated advisory vital signs monitors was associated with an improvement in the proportion of rapid response team-calls triggered by respiratory criteria, increased survival of patients receiving rapid response team calls, and decreased time required for vital signs measurement and recording (NCT01197326).
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| 32. |
- Collén, Anna, et al.
(författare)
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Primary recovery of a genetically engineered Trichoderma reesei endoglucanase I (Cel 7B) fusion protein in cloud point extraction systems.
- 2002
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Ingår i: Biotechnology and Bioengineering. - : Wiley. - 1097-0290 .- 0006-3592. ; 78:4, s. 385-394
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Tidskriftsartikel (refereegranskat)abstract
- Here we present data to demonstrate how partitioning of a hydrophilic enzyme can be directed to the hydrophobic detergent-enriched phase of an aqueous two-phase system by addition of short stretches of amino acid residues to the protein molecule. The target enzyme was the industrially important endoglucanase I, EGI (endo-1,4-beta-D-glucan-4-glucanohydrolase, EC 3.2.1.4, Cel7B) of Trichoderma reesei. We investigated the partitioning of three EGI variants containing various C-terminal peptide extensions including Trp-Pro motifs of different lengths and localizations. Additionally, a recently developed system composed of the thermoseparating copolymer HM-EOPO was utilized to study the effects of fusion tags. The addition of peptides containing tryptohan residues enhanced the partitioning of EGI to the HM-EOPO-rich phase. The system composed of a nonionic detergent (Agrimul NRE1205) resulted in the highest partition coefficient (K = 31) and yield (90%) with the construct EGI(core-P5)(WP)(4) containing (Trp-Pro)(4) after a short linker stretch. A recombinant strain of T. reesei Rut-C30 for large-scale production was constructed in which the fusion protein EGI(core-P5)(WP)(4) was expressed from the strong promoter of the cellulase gene cbh1. The fusion protein was successfully expressed and secreted from the fungus during shake-flask cultivations. Cultivation in a 28-L bioreactor however, revealed that the fusion protein is sensitive to proteases. Consequently, only low production levels were obtained in large-scale production trials.
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| 33. |
- Fiore, Christopher, et al.
(författare)
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Utility of multispectral imaging in automated quantitative scoring of immunohistochemistry
- 2012
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Ingår i: Journal of Clinical Pathology. - London, United Kingdom : BMJ Publishing Group Ltd. - 0021-9746 .- 1472-4146. ; 65:6, s. 496-502
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Tidskriftsartikel (refereegranskat)abstract
- Background: Automated scanning devices and image analysis software provide a means to overcome the limitations of manual semiquantitative scoring of immunohistochemistry. Common drawbacks to automated imaging systems include an inability to classify tissue type and an inability to segregate cytoplasmic and nuclear staining.Methods: Immunohistochemistry for the membranous marker a-catenin, the cytoplasmic marker stathmin and the nuclear marker Ki-67 was performed on tissue microarrays (TMA) of archival formalin-fixed paraffin-embedded tissue comprising 471 (alpha-catenin and stathmin) and 511 (Ki-67) cases of prostate adenocarcinoma. These TMA were quantitatively analysed using two commercially available automated image analysers, the Ariol SL-50 system and the Nuance system from CRi. Both systems use brightfield microscopy for automated, unbiased and standardised quantification of immunohistochemistry, while the Nuance system has spectral deconvolution capabilities. Results Overall concordance between scores from both systems was excellent (r=0.90; 0.83-0.95). The software associated with the multispectral imager allowed accurate automated classification of tissue type into epithelial glandular structures and stroma, and a single-step segmentation of staining into cytoplasmic or nuclear compartments allowing independent evaluation of these areas. The Nuance system, however, was not able to distinguish reliably between tumour and non-tumour tissue. In addition, variance in the labour and time required for analysis between the two systems was also noted.Conclusion: Despite limitations, this study suggests some beneficial role for the use of a multispectral imaging system in automated analysis of immunohistochemistry.
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| 34. |
- Flavin, Richard, et al.
(författare)
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SPINK1 protein expression and prostate cancer progression
- 2014
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Ingår i: Clinical Cancer Research. - Philadelphia, USA : American Association for Cancer Research. - 1078-0432 .- 1557-3265. ; 20:18, s. 4904-11
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: SPINK1 overexpression has been described in prostate cancer and is linked with poor prognosis in many cancers. The objective of this study was to characterize the association between SPINK1 overexpression and prostate cancer-specific survival.Experimental design: The study included 879 participants in the U.S. Physicians' Health Study and Health Professionals Follow-Up Study, diagnosed with prostate cancer (1983-2004) and treated by radical prostatectomy. Protein tumor expression of SPINK1 was evaluated by immunohistochemistry on tumor tissue microarrays.Results: Seventy-four of 879 (8%) prostate cancer tumors were SPINK1 positive. Immunohistochemical data were available for PTEN, p-Akt, pS6, stathmin, androgen receptor (AR), and ERG (as a measure of the TMPRSS2:ERG translocation). Compared with SPINK1-negative tumors, SPINK1-positive tumors showed higher PTEN and stathmin expression, and lower expression of AR (P < 0.01). SPINK1 overexpression was seen in 47 of 427 (11%) ERG-negative samples and in 19 of 427 (4%) ERG-positive cases (P = 0.0003). We found no significant associations between SPINK1 status and Gleason grade or tumor stage. There was no association between SPINK1 expression and biochemical recurrence (P = 0.56). Moreover, there was no association between SPINK1 expression and prostate cancer mortality (there were 75 lethal cases of prostate cancer during a mean of 13.5 years follow-up; HR = 0.71; 95% confidence interval, 0.29-1.76).Conclusions: Our results suggest that SPINK1 protein expression may not be a predictor of recurrence or lethal prostate cancer amongst men treated by radical prostatectomy. SPINK1 and ERG protein expression do not seem to be entirely mutually exclusive, as some previous studies have suggested.
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| 35. |
- Gossner, Martin M., et al.
(författare)
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Native Fauna on Exotic Trees : Phylogenetic Conservatism and Geographic Contingency in Two Lineages of Phytophages on Two Lineages of Trees
- 2009
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Ingår i: American Naturalist. - : University of Chicago Press. - 0003-0147 .- 1537-5323. ; 173:5, s. 599-614
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Tidskriftsartikel (refereegranskat)abstract
- The relative roles of evolutionary history and geographical and ecological contingency for community assembly remain unknown. Plant species, for instance, share more phytophages with closer relatives (phylogenetic conservatism), but for exotic plants introduced to another continent, this may be overlaid by geographically contingent evolution or immigration from locally abundant plant species (mass effects). We assessed within local forests to what extent exotic trees (Douglas-fir, red oak) recruit phytophages (Coleoptera, Heteroptera) from more closely or more distantly related native plants. We found that exotics shared more phytophages with natives from the same major plant lineage (angiosperms vs. gymnosperms) than with natives from the other lineage. This was particularly true for Heteroptera, and it emphasizes the role of host specialization in phylogenetic conservatism of host use. However, for Coleoptera on Douglas-fir, mass effects were important: immigration from beech increased with increasing beech abundance. Within a plant phylum, phylogenetic proximity of exotics and natives increased phytophage similarity, primarily in younger Coleoptera clades on angiosperms, emphasizing a role of past codiversification of hosts and phytophages. Overall, phylogenetic conservatism can shape the assembly of local phytophage communities on exotic trees. Whether it outweighs geographic contingency and mass effects depends on the interplay of phylogenetic scale, local abundance of native tree species, and the biology and evolutionary history of the phytophage taxon.
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| 36. |
- Guschanski, Katerina, Dr. 1978-, et al.
(författare)
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Next-Generation Museomics Disentangles One of the Largest Primate Radiations
- 2013
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Ingår i: Systematic Biology. - : Oxford University Press (OUP). - 1063-5157 .- 1076-836X. ; 62:4, s. 539-554
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Tidskriftsartikel (refereegranskat)abstract
- Guenons (tribe Cercopithecini) are one of the most diverse groups of primates. They occupy all of sub-Saharan Africa and show great variation in ecology, behavior, and morphology. This variation led to the description of over 60 species and subspecies. Here, using next-generation DNA sequencing (NGS) in combination with targeted DNA capture, we sequenced 92 mitochondrial genomes from museum-preserved specimens as old as 117 years. We infer evolutionary relationships and estimate divergence times of almost all guenon taxa based on mitochondrial genome sequences. Using this phylogenetic framework, we infer divergence dates and reconstruct ancestral geographic ranges. We conclude that the extraordinary radiation of guenons has been a complex process driven by, among other factors, localized fluctuations of African forest cover. We find incongruences between phylogenetic trees reconstructed from mitochondrial and nuclear DNA sequences, which can be explained by either incomplete lineage sorting or hybridization. Furthermore, having produced the largest mitochondrial DNA data set from museum specimens, we document how NGS technologies can “unlock” museum collections, thereby helping to unravel the tree-of-life. [Museum collection; next-generation DNA sequencing; primate radiation; speciation; target capture.]
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| 37. |
- Harrison, Stephan, et al.
(författare)
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Glaciar Leon, Chilean Patagonia: late-Holocene chronology and geomorphology
- 2008
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Ingår i: Holocene. - : SAGE Publications. - 0959-6836. ; 18:4, s. 643-652
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Tidskriftsartikel (refereegranskat)abstract
- Glaciar Leon is a temperate, grounded outlet of the eastern North Patagonian Icefield (NPI). It terminates at an active calving margin in Lago Leones, a 10 km long proglacial lake. We take a multidisciplinary approach to its description and use ASTER imagery and clast sedimentology to describe the geomorphology of the glacier and its associated moraines. We date periods of glacier retreat over the last 2500 years using a combination of lichenometric, dendrochronological, cosmogenic and optically stimulated luminescence techniques and show that the glacier receded from a large terminal moraine complex some 2500 years ago and underwent further significant recession from nineteenth-century moraine limits. The moraine dates indicate varying retreat rates, in conjunction with significant downwasting. The bathymetry of Lago Leones is characterized by distinct ridges interpreted as moraine ridges that dissect the lake into several basins, with water depths reaching 360 m. The fluctuations of Glaciar Leon appear to have been controlled by the interplay between climatic forcing and calving dynamics.
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| 38. |
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| 39. |
- Hermansen, Jo S., et al.
(författare)
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Hybrid speciation through sorting of parental incompatibilities in Italian sparrows
- 2014
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Ingår i: Molecular Ecology. - : Wiley. - 0962-1083. ; 23, s. 5831-5842
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Tidskriftsartikel (refereegranskat)abstract
- Speciation by hybridization is emerging as a significant contributor to biological diversification. Yet, little is known about the relative contributions of (i) evolutionary novelty and (ii) sorting of pre-existing parental incompatibilities to the build-up of reproductive isolation under this mode of speciation. Few studies have addressed empirically whether hybrid animal taxa are intrinsically isolated from their parents, and no study has so far investigated by which of the two aforementioned routes intrinsic barriers evolve. Here, we show that sorting of pre-existing parental incompatibilities contributes to intrinsic isolation of a hybrid animal taxon. Using a genomic cline framework, we demonstrate that the sex-linked and mitonuclear incompatibilities isolating the homoploid hybrid Italian sparrow at its two geographically separated hybrid–parent boundaries represent a subset of those contributing to reproductive isolation between its parent species, house and Spanish sparrows. Should such a sorting mechanism prove to be pervasive, the circumstances promoting homoploid hybrid speciation may be broader than currently thought, and indeed, there may be many cryptic hybrid taxa separated from their parent species by sorted, inherited incompatibilities.
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| 40. |
- Hunsicker, Mary E., et al.
(författare)
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Functional responses and scaling in predator-prey interactions of marine fishes : contemporary issues and emerging concepts
- 2011
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Ingår i: Ecology Letters. - : Wiley-Blackwell. - 1461-023X .- 1461-0248. ; 14:12, s. 1288-1299
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Forskningsöversikt (refereegranskat)abstract
- Predatorprey interactions are a primary structuring force vital to the resilience of marine communities and sustainability of the worlds oceans. Human influences on marine ecosystems mediate changes in species interactions. This generality is evinced by the cascading effects of overharvesting top predators on the structure and function of marine ecosystems. It follows that ecological forecasting, ecosystem management, and marine spatial planning require a better understanding of food web relationships. Characterising and scaling predatorprey interactions for use in tactical and strategic tools (i.e. multi-species management and ecosystem models) are paramount in this effort. Here, we explore what issues are involved and must be considered to advance the use of predatorprey theory in the context of marine fisheries science. We address pertinent contemporary ecological issues including (1) the approaches and complexities of evaluating predator responses in marine systems; (2) the scaling up of predatorprey interactions to the population, community, and ecosystem level; (3) the role of predatorprey theory in contemporary fisheries and ecosystem modelling approaches; and (4) directions for the future. Our intent is to point out needed research directions that will improve our understanding of predatorprey interactions in the context of the sustainable marine fisheries and ecosystem management.
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| 41. |
- Jarvis, Erich D., et al.
(författare)
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Whole-genome analyses resolve early branches in the tree of life of modern birds
- 2014
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 346:6215, s. 1320-1331
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Tidskriftsartikel (refereegranskat)abstract
- To better determine the history of modern birds, we performed a genome-scale phylogenetic analysis of 48 species representing all orders of Neoaves using phylogenomic methods created to handle genome-scale data. We recovered a highly resolved tree that confirms previously controversial sister or close relationships. We identified the first divergence in Neoaves, two groups we named Passerea and Columbea, representing independent lineages of diverse and convergently evolved land and water bird species. Among Passerea, we infer the common ancestor of core landbirds to have been an apex predator and confirm independent gains of vocal learning. Among Columbea, we identify pigeons and flamingoes as belonging to sister clades. Even with whole genomes, some of the earliest branches in Neoaves proved challenging to resolve, which was best explained by massive protein-coding sequence convergence and high levels of incomplete lineage sorting that occurred during a rapid radiation after the Cretaceous-Paleogene mass extinction event about 66 million years ago.
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| 42. |
- Law, PJ, et al.
(författare)
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Genome-wide association analysis implicates dysregulation of immunity genes in chronic lymphocytic leukaemia
- 2017
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8, s. 14175-
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Tidskriftsartikel (refereegranskat)abstract
- Several chronic lymphocytic leukaemia (CLL) susceptibility loci have been reported; however, much of the heritable risk remains unidentified. Here we perform a meta-analysis of six genome-wide association studies, imputed using a merged reference panel of 1,000 Genomes and UK10K data, totalling 6,200 cases and 17,598 controls after replication. We identify nine risk loci at 1p36.11 (rs34676223, P=5.04 × 10−13), 1q42.13 (rs41271473, P=1.06 × 10−10), 4q24 (rs71597109, P=1.37 × 10−10), 4q35.1 (rs57214277, P=3.69 × 10−8), 6p21.31 (rs3800461, P=1.97 × 10−8), 11q23.2 (rs61904987, P=2.64 × 10−11), 18q21.1 (rs1036935, P=3.27 × 10−8), 19p13.3 (rs7254272, P=4.67 × 10−8) and 22q13.33 (rs140522, P=2.70 × 10−9). These new and established risk loci map to areas of active chromatin and show an over-representation of transcription factor binding for the key determinants of B-cell development and immune response.
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| 43. |
- Law, Philip J., et al.
(författare)
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Genome-wide association analysis of chronic lymphocytic leukaemia, Hodgkin lymphoma and multiple myeloma identifies pleiotropic risk loci
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- B-cell malignancies (BCM) originate from the same cell of origin, but at different maturation stages and have distinct clinical phenotypes. Although genetic risk variants for individual BCMs have been identified, an agnostic, genome-wide search for shared genetic susceptibility has not been performed. We explored genome-wide association studies of chronic lymphocytic leukaemia (CLL, N = 1,842), Hodgkin lymphoma (HL, N = 1,465) and multiple myeloma (MM, N = 3,790). We identified a novel pleiotropic risk locus at 3q22.2 (NCK1, rs11715604, P = 1.60 × 10-9) with opposing effects between CLL (P = 1.97 × 10-8) and HL (P = 3.31 × 10-3). Eight established non-HLA risk loci showed pleiotropic associations. Within the HLA region, Ser37 + Phe37 in HLA-DRB1 (P = 1.84 × 10-12) was associated with increased CLL and HL risk (P = 4.68 × 10-12), and reduced MM risk (P = 1.12 × 10-2), and Gly70 in HLA-DQB1 (P = 3.15 × 10-10) showed opposing effects between CLL (P = 3.52 × 10-3) and HL (P = 3.41 × 10-9). By integrating eQTL, Hi-C and ChIP-seq data, we show that the pleiotropic risk loci are enriched for B-cell regulatory elements, as well as an over-representation of binding of key B-cell transcription factors. These data identify shared biological pathways influencing the development of CLL, HL and MM. The identification of these risk loci furthers our understanding of the aetiological basis of BCMs.
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| 44. |
- Mason, Richard, et al.
(författare)
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Vertical reworking of sediment by the cased caddisfly Glossosomatidae (Agapetus fuscipes) increases sand exposure and availability in armoured gravel-bed rivers
- 2022
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Ingår i: Geomorphology. - : Elsevier. - 0169-555X .- 1872-695X. ; 418
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Tidskriftsartikel (refereegranskat)abstract
- Landscapes and ecosystems are the result of two-way interactions between hydro-geomorphic and biological processes. Many animals, particularly those that build structures or transport sediment, are important biogeomorphic agents. Glossosomatidae caddisfly larvae (Insecta, Trichoptera) are globally widespread and abundant inhabitants of gravel-bed rivers. Glossosomatidae build mobile cases from sand that they transport over the river bed. However, there is limited understanding on how Glossosomatidae bioconstructions may influence sand distribution in rivers or how their zoogeomorphic behaviours are influenced by hydraulics or characteristics of the river bed. First, we conducted surveys to quantify the magnitude of sand incorporated into Glossosomatidae (Agapetus fuscipes) cases within a UK river. Second, we studied A. fuscipes movement behaviour and quantified the direction and magnitude of sediment reworking, in a flume, under differing flow velocity and gravel size treatments. We found that 99 % of A. fuscipes larvae transported sediment vertically upwards. This resulted in an average conveyance per larvae of 0.06 g sand upwards by 25 mm (maximum of 50 mm). In gravel beds with a coarse surface layer, this resulted in displacement of sand from sheltered interstices onto the surface of exposed gravel particles. In the flume, this behaviour was maintained even at high flows, sufficient to entrain empty cases from these locations. Whilst the mass of sediment moved by individual larvae is small, dense populations of Glossosomatidae larvae may have important consequences for the vertical distribution of sand in rivers. At our field site, A. fuscipes case density averaged 2192 cases m- 2, equivalent to 1.4 t km-1. This finding is important because in gravel-bed rivers frequented by Glossosomatidae larvae, sediment transport is typically limited by the availability of entrainable fine grain sediment at the surface. We discuss the implications of this sediment movement for river bed sedimentary structure, the transport of sand and gravel, and the possible role of Glossosomatidae larvae as ecosystem engineers.
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| 45. |
- Mountjoy, Margo, et al.
(författare)
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2023 International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs)
- 2023
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Ingår i: British Journal of Sports Medicine. - : BMJ Publishing Group Ltd. - 0306-3674 .- 1473-0480. ; 57:17, s. 1073-1097
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Relative Energy Deficiency in Sport (REDs) was first introduced in 2014 by the International Olympic Committee's expert writing panel, identifying a syndrome of deleterious health and performance outcomes experienced by female and male athletes exposed to low energy availability (LEA; inadequate energy intake in relation to exercise energy expenditure). Since the 2018 REDs consensus, there have been >170 original research publications advancing the field of REDs science, including emerging data demonstrating the growing role of low carbohydrate availability, further evidence of the interplay between mental health and REDs and more data elucidating the impact of LEA in males. Our knowledge of REDs signs and symptoms has resulted in updated Health and Performance Conceptual Models and the development of a novel Physiological Model. This Physiological Model is designed to demonstrate the complexity of either problematic or adaptable LEA exposure, coupled with individual moderating factors, leading to changes in health and performance outcomes. Guidelines for safe and effective body composition assessment to help prevent REDs are also outlined. A new REDs Clinical Assessment Tool-Version 2 is introduced to facilitate the detection and clinical diagnosis of REDs based on accumulated severity and risk stratification, with associated training and competition recommendations. Prevention and treatment principles of REDs are presented to encourage best practices for sports organisations and clinicians. Finally, methodological best practices for REDs research are outlined to stimulate future high-quality research to address important knowledge gaps.
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| 46. |
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| 47. |
- Qvarnström, Anna, et al.
(författare)
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Speciation through evolution of sex-linked genes
- 2009
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Ingår i: Heredity. - : Springer Science and Business Media LLC. - 0018-067X .- 1365-2540. ; 102:1, s. 4-15
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Forskningsöversikt (refereegranskat)abstract
- Identification of genes involved in reproductive isolation opens novel ways to investigate links between stages of the speciation process. Are the genes coding for ecological adaptations and sexual isolation the same that eventually lead to hybrid sterility and inviability? We review the role of sex-linked genes at different stages of speciation based on four main differences between sex chromosomes and autosomes; ( 1) relative speed of evolution, ( 2) non-random accumulation of genes, ( 3) exposure of incompatible recessive genes in hybrids and ( 4) recombination rate. At early stages of population divergence ecological differences appear mainly determined by autosomal genes, but fast-evolving sex-linked genes are likely to play an important role for the evolution of sexual isolation by coding for traits with sex-specific fitness effects ( for example, primary and secondary sexual traits). Empirical evidence supports this expectation but mainly in female-heterogametic taxa. By contrast, there is clear evidence for both strong X- and Z-linkage of hybrid sterility and inviability at later stages of speciation. Hence genes coding for sexual isolation traits are more likely to eventually cause hybrid sterility when they are sex-linked. We conclude that the link between sexual isolation and evolution of hybrid sterility is more intuitive in male-heterogametic taxa because recessive sexually antagonistic genes are expected to quickly accumulate on the X-chromosome. However, the broader range of sexual traits that are expected to accumulate on the Z-chromosome may facilitate adaptive speciation in female-heterogametic species by allowing male signals and female preferences to remain in linkage disequilibrium despite periods of gene flow.
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| 48. |
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| 49. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 50. |
- Singh, Amika S, et al.
(författare)
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Effects of physical activity interventions on cognitive and academic performance in children and adolescents : a novel combination of a systematic review and recommendations from an expert panel
- 2019
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Ingår i: British Journal of Sports Medicine. - : BMJ Publishing Group Ltd. - 0306-3674 .- 1473-0480. ; 53, s. 640-647
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To summarise the current evidence on the effects of physical activity (PA) interventions on cognitive and academic performance in children, and formulate research priorities and recommendations. DESIGN: Systematic review (following PRISMA guidelines) with a methodological quality assessment and an international expert panel. We based the evaluation of the consistency of the scientific evidence on the findings reported in studies rated as of high methodological quality. DATA SOURCES: PubMed, PsycINFO, Cochrane Central, Web of Science, ERIC, and SPORTDiscus. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: PA-intervention studies in children with at least one cognitive or academic performance assessment. RESULTS: Eleven (19%) of 58 included intervention studies received a high-quality rating for methodological quality: four assessed effects of PA interventions on cognitive performance, six assessed effects on academic performance, and one on both. All high-quality studies contrasted the effects of additional/adapted PA activities with regular curriculum activities. For cognitive performance 10 of 21 (48%) constructs analysed showed statistically significant beneficial intervention effects of PA, while for academic performance, 15 of 25 (60%) analyses found a significant beneficial effect of PA. Across all five studies assessing PA effects on mathematics, beneficial effects were reported in six out of seven (86%) outcomes.Experts put forward 46 research questions. The most pressing research priority cluster concerned the causality of the relationship between PA and cognitive/academic performance. The remaining clusters pertained to PA characteristics, moderators and mechanisms governing the 'PA-performance' relationship and miscellaneous topics. CONCLUSION: There is currently inconclusive evidence for the beneficial effects of PA interventions on cognitive and overall academic performance in children. We conclude that there is strong evidence for beneficial effects of PA on maths performance.The expert panel confirmed that more 'high-quality' research is warranted. By prioritising the most important research questions and formulating recommendations we aim to guide researchers in generating high-quality evidence. Our recommendations focus on adequate control groups and sample size, the use of valid and reliable measurement instruments for physical activity and cognitive performance, measurement of compliance and data analysis. PROSPERO REGISTRATION NUMBER: CRD42017082505.
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