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991.
992.
Jeanette Edwards 《Ethnos》2013,78(3):413-431
This paper looks through the ethnographic lens of ‘new reproductive and genetic technologies’ (NRGT) at the idiom of ‘make-up’ in English understandings of personhood and relatedness. In the kinship thinking of interest here, persons are both ‘made’ and ‘made-up’. There are both unpredictable and inevitable elements in the way in which people ‘turn-out’ and their character or personality is meant to be idiosyncratic, lumpy and unique. The paper draws on the way in which residents of a town in the north of England explore possibilities presented by NRGT in ways that make explicit their understandings of personal identity, interpersonal relatedness and communal belonging. The paper attempts to integrate the quotidian and personal narratives of residents with broader social and economic changes occurring in their town.  相似文献   
993.
ABSTRACT

In spite of suspected circadian differences between different ancestral groups, most human studies have used individuals of European descent. This also applies to three recent genome-wide association studies (GWAS), which pinpointed a number of chronotype loci. We investigated the distribution of these hits in different 1000 Genomes populations. We found 6 out of the 41 alleles previously identified by GWAS in European participants (in the genes RGS16, PER2 and AK5 and between the genes APH1A and CA14) to be absent from some non-European population groups. This highlights the need for ancestral diversity in circadian research and may reflect differences affecting the phenotype of individuals of East Asian ancestry.  相似文献   
994.
K Ezawa  H Innan 《Heredity》2013,111(5):364-374
Traditionally, population genetics focuses on the dynamics of frequencies of alleles acquired by mutations on germ-lines, because only such mutations are heritable. Typical genotyping experiments, however, use DNA from some somatic tissues such as blood, which harbors somatic mutations at the current generation in addition to germ-line mutations accumulated since the most recent common ancestor of the sample. This common practice may sometimes cause erroneous interpretations of polymorphism data, unless we properly understand the role of somatic mutations in population genetics. We here introduce a very basic theoretical framework of population genetics with somatic mutations taken into account. It is easy to imagine that somatic mutations at the current generation simply add individual-specific variations, as errors in mutation detection do. Our theory quantifies this increment under various conditions. We find that the major contribution of somatic mutations plus errors is to very rare variants, particularly to singletons. The relative contribution is markedly large when mutations are deleterious. Because negative selection also increases rare variants, it is important to distinguish the roles of these mutually confounding factors when we interpret the data, even after correcting for demography. We apply this theory to human copy number variations (CNVs), for which the composite effect of somatic mutations and errors may not be negligible. Using genome-wide CNV data, we demonstrate how the joint action of the two factors, selection and somatic mutations plus errors, shapes the observed pattern of polymorphism.  相似文献   
995.
BackgroundLead (Pb) is a worldwide concern due to its persistent property in the environment. However, due to diminutive evidence and elusiveness, the impact of lead exposure on the biochemical and haematological parameter in school-age children is not well established.AimThis study primarily aimed to investigate blood lead (BL) in children and its association with haematological and biochemical parameter.MethodsA total of 43 children (4–12 years) were recruited in each control and study group. Furthermore, the study group were subdivided into two groups (group A (<10 μg/dl) and group B (>10 μg/dl)). BL level, haematological parameter including haemoglobin, packed cell volume, red blood cells, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, total leukocytes count, neutrophils, lymphocytes, monocytes, mean corpuscular volume, red cell distribution width, eosinophil’s, platelets in the whole blood and biochemical parameter such as liver function test (total bilirubin, alkaline phosphatase, serum glutamic-oxaloacetic transaminase, serum glutamic-pyruvic transaminase, total protein, albumin) and kidney function test (sodium, potassium, blood urea nitrogen, creatinine) in serum were measured using anodic stripping voltammeter (ASV), Cell-Dyn Ruby Haematology analyser, Beckman coulter Unicel Dxc 800 Synchron Clinical analyser respectively.ResultsThe arithmetical mean of BL level was 19.93 ± 9.22 μg/dl (median: 17.5 μg/dl; range 9.1–37.4 μg/dl). Only 21 % children had BL levels <10 μg/dl and there were 79 % children with BL levels >10 μg/dl. Blood mean corpuscular haemoglobin concentration, Neutrophils, Monocytes were significantly higher between the control and study group. Additionally, haemoglobin, packed cell volume, red blood cells, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, Lymphocytes and mean corpuscular volume intensities were significantly lower in >10 μg/dl group whereas total leukocytes count, neutrophils, monocytes, red cell distribution width, eosinophil’s, platelets levels were statistically higher (p < 0.001).Serum alkaline phosphatase, serum glutamic-oxaloacetic transaminase, total protein, were higher (p < 0.05) and sodium, albumin were significantly lower in the study group. The mean value of sodium, potassium, total bilirubin, alkaline phosphatase, serum glutamic-pyruvic transaminase, total protein and blood urea nitrogen, creatinine in two groups (<10 μg/dl and >10 μg/dl) was not significantly different. Serum glutamic-oxaloacetic transaminase level was significantly higher (p = 0.015) while albumin levels were significantly lower (p = 0.034) in >10 μg/dl group. A statistically significant correlation of BL levels with all haematological parameters was also observed. Creatinine is positively and albumin was negatively correlated with BL levels.ConclusionThe outcomes specify that high BL levels were significantly associated with higher haematological and biochemical indices in exposed children. However, lead like noxious metals severely affected the haematological, kidney and liver health of children.  相似文献   
996.
Temperature passively affects biological processes involved in plant growth. Therefore, it is challenging to study the dedicated temperature signalling pathways that orchestrate thermomorphogenesis, a suite of elongation growth-based adaptations that enhance leaf-cooling capacity. We screened a chemical library for compounds that restored hypocotyl elongation in the pif4-2–deficient mutant background at warm temperature conditions in Arabidopsis thaliana to identify modulators of thermomorphogenesis. The small aromatic compound ‘Heatin’, containing 1-iminomethyl-2-naphthol as a pharmacophore, was selected as an enhancer of elongation growth. We show that ARABIDOPSIS ALDEHYDE OXIDASES redundantly contribute to Heatin-mediated hypocotyl elongation. Following a chemical proteomics approach, the members of the NITRILASE1-subfamily of auxin biosynthesis enzymes were identified among the molecular targets of Heatin. Our data reveal that nitrilases are involved in promotion of hypocotyl elongation in response to high temperature and Heatin-mediated hypocotyl elongation requires the NITRILASE1-subfamily members, NIT1 and NIT2. Heatin inhibits NIT1-subfamily enzymatic activity in vitro and the application of Heatin accordingly results in the accumulation of NIT1-subfamily substrate indole-3-acetonitrile in vivo. However, levels of the NIT1-subfamily product, bioactive auxin (indole-3-acetic acid), were also significantly increased. It is likely that the stimulation of hypocotyl elongation by Heatin might be independent of its observed interaction with NITRILASE1-subfamily members. However, nitrilases may contribute to the Heatin response by stimulating indole-3-acetic acid biosynthesis in an indirect way. Heatin and its functional analogues present novel chemical entities for studying auxin biology.  相似文献   
997.
998.
The problem of complex adaptations is studied in two largely disconnected research traditions: evolutionary biology and evolutionary computer science. This paper summarizes the results from both areas and compares their implications. In evolutionary computer science it was found that the Darwinian process of mutation, recombination and selection is not universally effective in improving complex systems like computer programs or chip designs. For adaptation to occur, these systems must possess “evolvability,” i.e., the ability of random variations to sometimes produce improvement. It was found that evolvability critically depends on the way genetic variation maps onto phenotypic variation, an issue known as the representation problem. The genotype-phenotype map determines the variability of characters, which is the propensity to vary. Variability needs to be distinguished from variations, which are the actually realized differences between individuals. The genotype-phenotype map is the common theme underlying such varied biological phenomena as genetic canalization, developmental constraints, biological versatility, developmental dissociability, and morphological integration. For evolutionary biology the representation problem has important implications: how is it that extant species acquired a genotype-phenotype map which allows improvement by mutation and selection? Is the genotype-phenotype map able to change in evolution? What are the selective forces, if any, that shape the genotype-phenotype map? We propose that the genotype-phenotype map can evolve by two main routes: epistatic mutations, or the creation of new genes. A common result for organismic design is modularity. By modularity we mean a genotype-phenotype map in which there are few pleiotropic effects among characters serving different functions, with pleiotropic effects falling mainly among characters that are part of a single functional complex. Such a design is expected to improve evolvability by limiting the interference between the adaptation of different functions. Several population genetic models are reviewed that are intended to explain the evolutionary origin of a modular design. While our current knowledge is insufficient to assess the plausibility of these models, they form the beginning of a framework for understanding the evolution of the genotype-phenotype map.  相似文献   
999.
Astyanax is well known as a model for developmental biology studies, particularly with regard to Mexico's cave populations. More than 130 species of Astyanax are already known, most of which live in South America. The occurrence of cryptic species and species complexes elucidated by chromosomal and genetic studies demonstrates that the relationship between morphology and molecular evolution is quite complex within this group. In this work, we demonstrate that morphology does not follow the path of vicariant processes observed in Astyanax fasciatus populations, which separated about three million years ago, although molecular data suggests its separation in two species.  相似文献   
1000.
The equations of evolutionary change by natural selection are commonly expressed in statistical terms. Fisher's fundamental theorem emphasizes the variance in fitness. Quantitative genetics expresses selection with covariances and regressions. Population genetic equations depend on genetic variances. How can we read those statistical expressions with respect to the meaning of natural selection? One possibility is to relate the statistical expressions to the amount of information that populations accumulate by selection. However, the connection between selection and information theory has never been compelling. Here, I show the correct relations between statistical expressions for selection and information theory expressions for selection. Those relations link selection to the fundamental concepts of entropy and information in the theories of physics, statistics and communication. We can now read the equations of selection in terms of their natural meaning. Selection causes populations to accumulate information about the environment.  相似文献   
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