405 research outputs found

    Racial environment and political participation

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    This research addresses the determinants of mass participation by developing a model of how the racial environment influences mass participation in the United States. Prior literature on this research question presents two competing expectations. The power-threat hypothesis predicts that a larger size of different racial groups in local areas increases citizen participation because of more intensive interracial con- flicts, while the relational goods hypothesis predicts that a larger size of different racial groups decreases participation because of less frequent interaction with other in-group members. Both hypotheses, however, are derived from rather weak theoretical expectations, and neither is consistently supported in empirical analyses. This research offers a solution to this puzzle by arguing that economic and political characteristics of local areas determine how the racial composition influences mass participation. Local economic and political competition is expected to structure the nature of interracial and intraracial relations and therefore influence the utility calculation associated with political participation. I hypothesize that the power-threat effect on citizen participation is observed only when the degree of economic or political competition is high, while the relational goods effect is observed only when the degree of economic or political competition is low. Empirical analysis using Verba, Schlozman, and Brady’s Citizen Participation Study offers supportive evidence for my hypotheses. This research offers the first theoretically-motivated, rigorous analysis and evidence of the impact of immediate racial environment on individuals’ participation

    Distorted Communication, Unequal Representation: Constituents Communicate Less to Representatives Not of Their Race

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    Communications from constituents strongly shape the representation politicians provide. However, if politicians hear less from some constituents than others, this unequal communication may lead to unequal representation. In this article, I present a field experiment demonstrating that constituents are less likely to communicate to representatives not of their race. The experiment exploited electoral rules in Maryland, where several multimember districts have both black and white representatives. I provided 8,829 residents of such districts an opportunity to communicate to one of their actual representatives, whose race I randomized. Both blacks and whites were markedly less likely to communicate to their representatives not of their race. These results imply that politicians receive racially distorted communication, hearing disproportionately infrequently from constituents unlike them. The fact that most racial minorities have white representatives may thus help explain both minorities' less frequent communication to their representatives and the diminished substantive representation minorities typically receive. © 2013, Midwest Political Science Association

    Multidecadal accumulation of anthropogenic and remineralized dissolved inorganic carbon along the Extended Ellett Line in the northeast Atlantic Ocean

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    Marine carbonate chemistry measurements have been carried out annually since 2009 during UK research cruises along the Extended Ellett Line (EEL), a hydrographic transect in the northeast Atlantic Ocean. The EEL intersects several water masses that are key to the global thermohaline circulation, and therefore the cruises sample a region in which it is critical to monitor secular physical and biogeochemical changes. We have combined results from these EEL cruises with existing quality-controlled observational data syntheses to produce a hydrographic time series for the EEL from 1981 to 2013. This reveals multidecadal increases in dissolved inorganic carbon (DIC) throughout the water column, with a near-surface maximum rate of 1.80 ± 0.45 µmol kg−1 yr−1. Anthropogenic CO2 accumulation was assessed, using simultaneous changes in apparent oxygen utilization (AOU) and total alkalinity (TA) as proxies for the biogeochemical processes that influence DIC. The stable carbon isotope composition of DIC (δ13CDIC) was also determined and used as an independent test of our method. We calculated a volume-integrated anthropogenic CO2 accumulation rate of 2.8 ± 0.4 mg C m−3 yr−1 along the EEL, which is about double the global mean. The anthropogenic CO2 component accounts for only 31 ± 6% of the total DIC increase. The remainder is derived from increased organic matter remineralization, which we attribute to the lateral redistribution of water masses that accompanies subpolar gyre contraction. Output from a general circulation ecosystem model demonstrates that spatiotemporal heterogeneity in the observations has not significantly biased our multidecadal rate of change calculations and indicates that the EEL observations have been tracking distal changes in the surrounding North Atlantic and Nordic Seas

    Infestation of shore crab gills by a free-living mussel species

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    Parasitic and commensal species can impact the structure and function of ecological communities and are typically highly specialized to overcome host defences. Here, we report multiple instances of a normally free-living species, the blue mussel Mytilus edulis Linnaeus, 1758, inhabiting the branchial chamber of the shore crab Carcinus maenas (Linnaeus, 1758) collected from widely separated geographical locations. A total of 127 C. maenas were examined from four locations in the English Channel, one location in the Irish Sea and two locations at the entrance of the Baltic Sea. The branchial chambers of three crabs (one from the English Channel and two from Gullmar Fjord, Sweden) were infested with mussels resembling the genus Mytilus. Sequencing at the Me15/16 locus on the polyphenolic adhesive protein gene confirmed the identity as M. edulis. Bivalve infestation always occurred in larger red male individuals. Up to 16 mussels, ranging from 2 to 11 mm in shell length, were found in each individual, either wedged between gill lamellae or attached to the branchial chamber inner wall. This is one of the first reports of a bivalve inhabiting crustacean gills and is an intriguing case of a normally free-living prey species infesting its predato

    Persistent Megalocystic Ovary Following in Vitro Fertilization in a Postpartum Patient with Polycystic Ovarian Syndrome

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    SummaryObjectiveOvarian hyperstimulation syndrome (OHSS) is more severe when pregnancy occurs, as the developing pregnancy produces human chorionic gonadotropin, which stimulates the ovary's persistent growth. If no pregnancy occurs, the syndrome will typically resolve within 1 week. In a maintained pregnancy, slow resolution of symptoms usually occurs over 1-2 months.Case ReportA 31-year-old woman, gravida 2, para 1, aborta 1, with polycystic ovary syndrome underwent in vitro fertilization (IVF) with clomiphene citrate and follicle-stimulating hormone/gonadotropin releasing hormone-antagonist stimulation. During transvaginal oocyte retrieval, enlarged bilateral ovaries were noted. She had an episode of OHSS after IVF/embryo transfer, for which paracentesis was performed three times. Pregnancy was achieved. Throughout antenatal examinations, bilateral ovaries were enlarged. She delivered a healthy baby by cesarean section at term. However, 1 month after delivery, the bilateral ovary had not shrunk, and levels of tumor markers CA125 and CA199 were 50.84 and 41.34 U/mL, respectively. At laparotomy for suspected malignancy, both adnexae formed “kissing ovaries”, which were multinodulated with yellow serous fluid. Specimens from wedge resection submitted for frozen section showed a benign ovarian cyst. The final pathology report showed bilateral follicle cysts.ConclusionWith the increasing use of gonadotropins in the management of infertility, ovarian enlargement secondary to hyperstimulation is common. Generally, symptoms appear between the 6th and 13th weeks of pregnancy and disappear thereafter. The hyperstimulated ovary often subsides after the first trimester. This case is unusual as the megalocystic ovary persisted after delivery. To the best of our knowledge, we report the first case of enlarged bilateral ovaries persisting 2 months after delivery

    Prostate cancer risk related to foods, food groups, macronutrients and micronutrients derived from the UK Dietary Cohort Consortium food diaries.

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    BACKGROUND/OBJECTIVES: The influence of dietary factors remains controversial for screen-detected prostate cancer and inconclusive for clinically detected disease. We aimed to examine these associations using prospectively collected food diaries. SUBJECTS/METHODS: A total of 1,717 prostate cancer cases in middle-aged and older UK men were pooled from four prospective cohorts with clinically detected disease (n=663), with routine data follow-up (means 6.6-13.3 years) and a case-control study with screen-detected disease (n=1054), nested in a randomised trial of prostate cancer treatments (ISCTRN 20141297). Multiple-day food diaries (records) completed by men prior to diagnosis were used to estimate intakes of 37 selected nutrients, food groups and items, including carbohydrate, fat, protein, dairy products, fish, meat, fruit and vegetables, energy, fibre, alcohol, lycopene and selenium. Cases were matched on age and diary date to at least one control within study (n=3528). Prostate cancer risk was calculated, using conditional logistic regression (adjusted for baseline covariates) and expressed as odds ratios in each quintile of intake (±95% confidence intervals). Prostate cancer risk was also investigated by localised or advanced stage and by cancer detection method. RESULTS: There were no strong associations between prostate cancer risk and 37 dietary factors. CONCLUSIONS: Prostate cancer risk, including by disease stage, was not strongly associated with dietary factors measured by food diaries in middle-aged and older UK men.Medical Research Council (Grant ID: MC_UU_12019/1), Medical Research Council Population Health Sciences Research Network, British Heart Foundation, Cancer Research UK (Grant ID: C8221/A19170), Department of Health, Food Standards Agency, Stroke Association, WCRF, National Institute for Health Research Health Technology Assessment Programme (Project IDs: 96/20/06, 96/20/99), National Cancer Research Institute (formed by Cancer Research UK, Medical Research Council, Department of Health)This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ejcn.2016.16

    The associations of anthropometric, behavioural and sociodemographic factors with circulating concentrations of IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3 in a pooled analysis of 16,024 men from 22 studies

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    Insulin-like growth factors (IGFs) and insulin-like growth factor binding proteins (IGFBPs) have been implicated in the aetiology of several cancers. To better understand whether anthropometric, behavioural, and sociodemographic factors may play a role in cancer risk via IGF signalling, we examined the cross-sectional associations of these exposures with circulating concentrations of IGFs (IGF-I, IGF-II) and IGFBPs (IGFBP-1, IGFBP-2, IGFBP-3). The Endogenous Hormones, Nutritional Biomarkers and Prostate Cancer Collaborative Group dataset includes individual participant data from 16,024 male controls (i.e. without prostate cancer) aged 22-89 years from 22 prospective studies. Geometric means of protein concentrations were estimated using analysis of variance, adjusted for relevant covariates. Older age was associated with higher concentrations of IGFBP-1 and IGFBP-2 and lower concentrations of IGF-I, IGF-II, and IGFBP-3. Higher body mass index was associated with lower concentrations of IGFBP-1 and IGFBP-2. Taller height was associated with higher concentrations of IGF-I and IGFBP-3 and lower concentrations of IGFBP-1. Smokers had higher concentrations of IGFBP-1 and IGFBP-2 and lower concentrations of IGFBP-3 than non-smokers. Higher alcohol consumption was associated with higher concentrations of IGF-II and lower concentrations of IGF-I and IGFBP-2. African Americans had lower concentrations of IGF-II, IGFBP-1, IGFBP-2 and IGFBP-3 and Hispanics had lower IGF-I, IGF-II and IGFBP-3 than non-Hispanic whites. These findings indicate that a range of anthropometric, behavioural, and sociodemographic factors are associated with circulating concentrations of IGFs and IGFBPs in men, which will lead to a greater understanding of the mechanisms through which these factors influence cancer risk. This article is protected by copyright. All rights reserved

    Three new pancreatic cancer susceptibility signals identified on chromosomes 1q32.1, 5p15.33 and 8q24.21.

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    Genome-wide association studies (GWAS) have identified common pancreatic cancer susceptibility variants at 13 chromosomal loci in individuals of European descent. To identify new susceptibility variants, we performed imputation based on 1000 Genomes (1000G) Project data and association analysis using 5,107 case and 8,845 control subjects from 27 cohort and case-control studies that participated in the PanScan I-III GWAS. This analysis, in combination with a two-staged replication in an additional 6,076 case and 7,555 control subjects from the PANcreatic Disease ReseArch (PANDoRA) and Pancreatic Cancer Case-Control (PanC4) Consortia uncovered 3 new pancreatic cancer risk signals marked by single nucleotide polymorphisms (SNPs) rs2816938 at chromosome 1q32.1 (per allele odds ratio (OR) = 1.20, P = 4.88x10 -15), rs10094872 at 8q24.21 (OR = 1.15, P = 3.22x10 -9) and rs35226131 at 5p15.33 (OR = 0.71, P = 1.70x10 -8). These SNPs represent independent risk variants at previously identified pancreatic cancer risk loci on chr1q32.1 ( NR5A2), chr8q24.21 ( MYC) and chr5p15.33 ( CLPTM1L- TERT) as per analyses conditioned on previously reported susceptibility variants. We assessed expression of candidate genes at the three risk loci in histologically normal ( n = 10) and tumor ( n = 8) derived pancreatic tissue samples and observed a marked reduction of NR5A2 expression (chr1q32.1) in the tumors (fold change -7.6, P = 5.7x10 -8). This finding was validated in a second set of paired ( n = 20) histologically normal and tumor derived pancreatic tissue samples (average fold change for three NR5A2 isoforms -31.3 to -95.7, P = 7.5x10 -4-2.0x10 -3). Our study has identified new susceptibility variants independently conferring pancreatic cancer risk that merit functional follow-up to identify target genes and explain the underlying biology

    Common genetic variants associated with pancreatic adenocarcinoma may also modify risk of pancreatic neuroendocrine neoplasms (vol 39, pg 360, 2018)

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    Pancreatic neuroendocrine neoplasms (pNEN) account for less than 5% of all pancreatic neoplasms and genetic association studies on susceptibility to the disease are limited. We sought to identify possible overlap of genetic susceptibility loci between pancreatic ductal adenocarcinoma (PDAC) and pNEN; therefore, PDAC susceptibility variants (n=23) from Caucasian genome-wide association studies (GWAS) were genotyped in 369 pNEN cases and 3,277 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium to evaluate the odds associated with pNEN risk, disease onset and tumor characteristics. Main effect analyses showed four PDAC susceptibility variants – rs9854771, rs1561927, rs9543325 and rs10919791 to be associated with pNEN risk. Subsequently, only associations with rs9543325, rs10919791 and rs1561927 were noteworthy with false positive report probability (FPRP) tests. Stratified analyses considering age at onset (50 year threshold), showed rs2736098, rs16986825 and rs9854771 to be associated with risk of developing pNEN at a younger age. Stratified analyses also showed some SNPs to be associated with different degrees of tumor grade, metastatic potential and functionality. Our results identify known GWAS PDAC susceptibility loci, which may also be involved in sporadic pNEN etiology and suggest that some genetic mechanisms governing pathogenesis of these two entities may be similar, with few of these loci being more influential in younger cases or tumor subtypes
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