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1.
Several studies have shown that mate choice based on condition leads to higher reproductive success of the choosing individual. Yet, a growing body of literature has failed to find support for mate choice based on mate condition, even when the choosing individual would clearly benefit from such a choice. This indicates that animals’ mate choice is often more complex than currently appreciated and that even well-founded expected preferences cannot be taken for granted. Using the broad-nosed pipefish, Syngnathus typhle, we manipulated male condition experimentally to explore whether it affects female mate choice. In this sex-role-reversed species, males care for the offspring in a specialised brood pouch. Males are the choosier sex, but given the opportunity, females are selective as well. During brooding, males can both provide embryos with nutrients and take up nutrients that originate from eggs deposited in the pouch, and embryo survival correlates positively with male condition. Together, this suggests that it would be beneficial for females to mate with males in high condition. However, we found no female preference for males in better condition. Thus, this study adds to the literature of mate choice that is unaffected by mate condition. Possible reasons for our result are discussed.  相似文献   
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Background

We sought to examine whether neighborhood deprivation is associated with participation in a large population-based health check. Such analyses will help answer the question whether health checks, which are designed to meet the needs of residents in deprived neighborhoods, may increase participation and prove to be more effective in preventing disease. In Europe, no study has previously looked at the association between neighborhood deprivation and participation in a population-based health check.

Methods

The study population comprised 12,768 persons invited for a health check including screening for ischemic heart disease and lifestyle counseling. The study population was randomly drawn from a population of 179,097 persons living in 73 neighborhoods in Denmark. Data on neighborhood deprivation (percentage with basic education, with low income and not in work) and individual socioeconomic position were retrieved from national administrative registers. Multilevel regression analyses with log links and binary distributions were conducted to obtain relative risks, intraclass correlation coefficients and proportional change in variance.

Results

Large differences between neighborhoods existed in both deprivation levels and neighborhood health check participation rate (mean 53%; range 35-84%). In multilevel analyses adjusted for age and sex, higher levels of all three indicators of neighborhood deprivation and a deprivation score were associated with lower participation in a dose-response fashion. Persons living in the most deprived neighborhoods had up to 37% decreased probability of participating compared to those living in the least deprived neighborhoods. Inclusion of individual socioeconomic position in the model attenuated the neighborhood deprivation coefficients, but all except for income deprivation remained statistically significant.

Conclusion

Neighborhood deprivation was associated with participation in a population-based health check in a dose-response manner, in which increasing neighborhood deprivation was associated with decreasing participation. This suggests the need to develop preventive health checks tailored to deprived neighborhoods.  相似文献   
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Several groups have reported protection against experimental SIV infection in macaques immunized with a whole inactivated virus vaccine. The aim of the current study was to investigate whether five macaques vaccinated with whole inactivated SIV and previously shown to be protected against challenge with two divergent strains of SIV grown on human cells could resist challenge with a subsequent homologous SIV grown on macaque cells. We show here that this same vaccine did not protect when the challenge virus was grown on primary cells of monkey origin.  相似文献   
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Boron neutron capture therapy (BNCT) is a chemoradio-therapeutic method for the treatment of cancer. It depends on the selective targeting of tumor cells by boron-containing compounds. One category of BNCT agents with potential to selectively target tumor cells may be thymidine derivatives substituted at the 3'-position with appropriate boron moieties. Thus, several thymidine analogues were synthesized with a carborane cluster bound to the 3'-position either through an ether or a carbon linkage. The latter are the first reported carborane-containing nucleosides in which the carboranyl entity is directly linked to the carbohydrate portion of the nucleoside by a carbon-carbon bond. Low but significant phosphorylation rates in the range of 0.18% that of thymidine were observed for the carbon-linked 3'-carboranyl thymidine analogues in phosphoryl transfer assays using recombinant preparations of thymidine kinases 1 (TK1) and thymidine kinases 2 (TK2). Some of the ether-linked 3'-carboranyl thymidine analogues appeared to be slightly unstable under acidic as well as phosphoryl transfer assay conditions and were, if at all, poor substrates for TK1.  相似文献   
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B‐cell differentiation is one of the most recognized examples of the progressive lineage commitment that is distinctive for stem cell systems. However, the characteristics of the stage just before a cell becomes restricted to the B‐cell lineage are less understood. Using single‐cell RNA sequencing technology, Rolink and colleagues are able to define the cellular heterogeneity at this step and challenge our understanding of developmental trajectories in early B‐lymphoid development (Alberti‐Servera et al, 2017 ).  相似文献   
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The Wilms’ tumour gene 1 (WT1) single nucleotide polymorphism (SNP) rs16754 has recently been described as an independent prognostic factor in acute myeloid leukaemia (AML) patients. It is of great interest to test whether WT1 SNPs can be used as a molecular marker in other cancer types in order to improve risk and treatment stratification. We performed sequencing analysis on all 10 exons of the WT1 gene in a total of 182 patients with clear cell renal cell carcinoma (ccRCC). Six different SNPs were identified, in descending order for minor allele frequency: rs2234582, rs16754, rs1799925, rs5030315, rs2234583, and rs2234581. At least one minor allele for WT1 SNP was identified in 61% of ccRCC patients. In the entire study population, only 6% carried two copies of the minor allele. The genotypes of WT1 SNPs in 78 tumour-free kidney tissue specimens were found to be in 95% concordance with corresponding tumour samples. No correlation was observed between WT1 SNP genotypes and RNA expression level. WT1 SNP genotypes did not associate with clinical and pathological characteristics. We found favourable outcomes associated with the homozygous minor allele for WT1 SNP. However, SNP genotypes did not show to be of prognostic significance when comparing wild-type versus homozygous or heterozygous for the minor allele in the entire cohort. None of the previously reported WT1 mutations in AML was found in the present study. A novel WT1 missense mutation was identified in only one patient. Our data suggest that common WT1 mutations are not involved in ccRCC. Due to too few cases harbouring the homozygous minor allele, the prognostic impact needs to be verified in larger study populations.  相似文献   
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In externally fertilizing species, the gametes of both males and females are exposed to the influences of the environment into which they are released. Sperm are sensitive to abiotic factors such as salinity, but they are also affected by biotic factors such as sperm competition. In this study, the authors compared the performance of sperm of three goby species, the painted goby, Pomatoschistus pictus, the two-spotted goby, Pomatoschistus flavescens, and the sand goby, Pomatoschistus minutus. These species differ in their distributions, with painted goby having the narrowest salinity range and sand goby the widest. Moreover, data from paternity show that the two-spotted goby experiences the least sperm competition, whereas in the sand goby sperm competition is ubiquitous. The authors took sperm samples from dissected males and exposed them to high salinity water (31 PSU) representing the North Sea and low salinity water (6 PSU) representing the brackish Baltic Sea Proper. They then used computer-assisted sperm analysis to measure the proportion of motile sperm and sperm swimming speed 10 min and 20 h after sperm activation. The authors found that sperm performance depended on salinity, but there seemed to be no relationship to the species' geographical distribution in relation to salinity range. The species differed in the proportion of motile sperm, but there was no significant decrease in sperm motility during 20 h. The sand goby was the only species with motile sperm after 72 h.  相似文献   
10.
During male–male competition, evolution can favor alternative reproductive tactics. This often results in a dominant morph that holds a resource, such as a nest for egg laying, which competes with a smaller sneaker morph that reproduces by stealing fertilizations. The salinity environment can influence male growth rates, for example, via osmoregulatory costs, which in turn may influence the use of sneaker tactics for small males competing for mating opportunities. Salinity can also affect sperm directly; however, little is known of how salinity influences sneaker tactics through sperm performance. We sampled males of the invasive round goby (Neogobius melanostomus) from two environments, a freshwater river and a brackish estuary. This fish has two male morphs: nest‐holding dark males and non‐nest‐holding light males. We examined the role of water salinity of 0, 8, and 16 on sperm performance and found that for estuarine males, a salinity of 0 reduced sperm velocity compared to a salinity of 8 and 16. Riverine males had low velocity in all salinities. Sperm viability also decreased by over 30% in 0 salinity, compared to 8 and 16, for fish from both environments. Gobies produce ejaculate contents in specialized glands that could in theory shield sperm in an adverse environment. However, gland contents did not improve sperm performance in our tests. Body mass and age estimates indicate that riverine males invested more in somatic growth compared to estuarine males. Estuarine light morph males had a high enough gonadosomatic index to indicate sneaker tactics. We propose that when sperm performance is low, such as for the riverine males, sneaker tactics are ineffective and will be selected against or phenotypically suppressed. Instead, we interpret the increased investment in somatic growth found in riverine males as a life‐history decision that is advantageous when defending a nest in the next reproductive season.  相似文献   
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