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1.
Fish finders have already been widely available in the fishing market for a number of years.However,the sizes of these fishfinders are too big and their prices are expensive to suit for the research of robotic fish or mini-submarine.The goal of thisresearch is to propose a low-cost fish detector and classifier which suits for underwater robot or submarine as a proximity sensor.With some pre-condition in hardware and algorithms,the experimental results show that the proposed design has good per-formance,with a detection rate of 100 % and a classification rate of 94 %.Both the existing type of fish and the group behaviorcan be revealed by statistical interpretations such as hovering passion and sparse swimming mode.  相似文献   
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Background

A number of neurodevelopmental syndromes are caused by mutations in genes encoding proteins that normally function in epigenetic regulation. Identification of epigenetic alterations occurring in these disorders could shed light on molecular pathways relevant to neurodevelopment.

Results

Using a genome-wide approach, we identified genes with significant loss of DNA methylation in blood of males with intellectual disability and mutations in the X-linked KDM5C gene, encoding a histone H3 lysine 4 demethylase, in comparison to age/sex matched controls. Loss of DNA methylation in such individuals is consistent with known interactions between DNA methylation and H3 lysine 4 methylation. Further, loss of DNA methylation at the promoters of the three top candidate genes FBXL5, SCMH1, CACYBP was not observed in more than 900 population controls. We also found that DNA methylation at these three genes in blood correlated with dosage of KDM5C and its Y-linked homologue KDM5D. In addition, parallel sex-specific DNA methylation profiles in brain samples from control males and females were observed at FBXL5 and CACYBP.

Conclusions

We have, for the first time, identified epigenetic alterations in patient samples carrying a mutation in a gene involved in the regulation of histone modifications. These data support the concept that DNA methylation and H3 lysine 4 methylation are functionally interdependent. The data provide new insights into the molecular pathogenesis of intellectual disability. Further, our data suggest that some DNA methylation marks identified in blood can serve as biomarkers of epigenetic status in the brain.  相似文献   
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Congenital nevi develop before birth and sometimes cover large areas of the body. They are presumed to arise from the acquisition of a gene mutation in an embryonic melanocyte that becomes trapped in the dermis during development. Mice bearing the Cdk4R24C::Tyr‐NRASQ61K transgenes develop congenital nevus‐like lesions by post‐natal day 10, from melanocytes escaping the confines of hair follicles. We interbred these mice with the collaborative cross (CC), a resource that enables identification of modifier genes for complex diseases (those where multiple genes are involved). We examined variation in nevus cell density in 66 CC strains and mapped a large‐effect quantitative trait locus (QTL) controlling nevus cell density to murine chromosome 9. The best candidate for a gene that exacerbates congenital nevus development in the context of an NRAS mutation is Cdon, a positive regulator of sonic hedgehog (Shh) that is expressed mainly in keratinocytes.  相似文献   
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Abstract: The fossil record of the callianassid genus Glypturus (Decapoda, Axiidea) is re‐evaluated. Our systematic revision, both of extant and fossil taxa, is based on major cheliped morphology only, thus providing an important impetus for palaeontological studies. Both spination and tuberculation of chelipeds are herein considered of great taxonomic importance. Presence of spines on the upper margins of the merus and propodus and the lower margin of the carpus are significant for generic assignment, whereas the extent of tuberculation on lateral surfaces of the propodus is important for assignment at the species level. Altogether, four extant and six exclusively fossil species of Glypturus are recognized. Several extinct callianassid taxa are now transferred to the genus, namely Callianassa berryi, Callianassa fraasi, Callianassa munieri, Callianassa pugnax and Callianassaspinosa; Callianassa pseudofraasi is considered a junior synonym of C. fraasi. Based on a comparison of ecological preferences of extant representatives, the presence of Glypturus in the fossil record is considered to be linked with tropical to subtropical, nearshore carbonate environments of normal salinity. We argue that Glypturus is of Tethyan origin, with a stratigraphical range going as far back as the Eocene. Since then, the genus migrated both westwards and eastwards, establishing present‐day communities in the western Atlantic and Indo‐West Pacific which both comprise several distinct species. In the presumed area of origin, the genus does no longer occur today. The exlusively fossil (middle Eocene) genus Eoglypturus from Italy is considered closely related to Glypturus and is thus assigned to the subfamily Callichirinae as well.  相似文献   
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The prevalence of a 9-base-pair (bp) deletion between the mitochondrial cytochrome oxidase II (MTCOX*2) and lysine tRNA (MTTK) genes (region V) has been used to estimate the genetic relationships among Asian and Pacific populations. Many East Asian and Pacific Island populations have been examined previously, but the mitochondrial DNA (mtDNA) diversity of the intervening Indonesian archipelago has not previously been systematically examined. The 17,500 islands of Indonesia currently contain nearly 213 million people and extensive cultural, linguistic, and, presumably, genetic diversity. This study of 1091 individuals representing 15 ethnic groups is the most extensive mtDNA survey to date of the Indonesian archipelago. Six distinct length polymorphisms in region V were observed within these 15 populations. The 9-bp deletion was found in every population examined at frequencies comparable to those of previously examined East Asian populations and substantially lower than those in most Pacific Island populations. Despite the inclusion of Austronesian-speaking populations and a Papuan-speaking population, there was no statistically significant heterogeneity in the frequency of the 9-bp deletion among the 15 populations (p = 0.09). These data indicate that substantial gene flow occurred among the populations at some time in the past. Our observations of no significant correlations between genetic and geographic distances (r = -0.04, p = 0.53) coupled with the extensive cultural and linguistic differences currently within the archipelago suggest that little gene flow among neighboring populations has occurred recently.  相似文献   
7.
Heart failure with preserved ejection fraction (HFpEF) is a growing healthcare burden worldwide and its prevalence is increasing. Diagnosing HFpEF is challenging and relies upon the presence of symptoms and/or signs of heart failure, preserved left ventricular systolic function, and evidence of diastolic dysfunction. Current diagnostic algorithms mainly rely on echocardiography (E/e’) and biomarkers (NT-proBNP). However, only a minority of patients with HFpEF are identified, and especially HFpEF patients at an early stage of the disease are easily missed. We propose to incorporate invasive stress testing, by means of right heart catheterisation at rest and during exercise, and accurate assessment of right ventricular function, by means of cardiac magnetic resonance imaging. These additions to the current diagnostic work-up will improve diagnostic sensitivity and accurate staging of HFpEF patients.  相似文献   
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The recent application of genome-wide, single nucleotide polymorphism (SNP) microarrays to investigate DNA copy number aberrations in cancer has provided unparalleled sensitivity for identifying genomic changes. In some instances the complexity of these changes makes them difficult to interpret, particularly when tumour samples are contaminated with normal (stromal) tissue. Current automated scoring algorithms require considerable manual data checking and correction, especially when assessing uncultured tumour specimens. To address these limitations we have developed a visual tool to aid in the analysis of DNA copy number data. Simulated DNA Copy Number (SiDCoN) is a spreadsheet-based application designed to simulate the appearance of B-allele and logR plots for all known types of tumour DNA copy number changes, in the presence or absence of stromal contamination. The system allows the user to determine the level of stromal contamination, as well as specify up to 3 different DNA copy number aberrations for up to 5000 data points (representing individual SNPs). This allows users great flexibility to assess simple or complex DNA copy number combinations. We demonstrate how this utility can be used to estimate the level of stromal contamination within tumour samples and its application in deciphering the complex heterogeneous copy number changes we have observed in a series of tumours. We believe this tool will prove useful to others working in the area, both as a training tool, and to aid in the interpretation of complex copy number changes.  相似文献   
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