黄河上游地区是中国贫困易发高发的地区。在2020年打赢脱贫攻坚战背景下,探讨该地区减贫转向特征和高质量发展路径,对实现区域可持续发展具有重要指导意义。本文通过梳理流域地区发展研究和国家战略需求,基于发展地理学视角,构建了面向流域减贫与发展的“五位一体”地理资本体系及其空间整合分析框架。在界定黄河上游地区范围的基础上,阐述了该地区的减贫转向与发展问题。研究发现：黄河上游地区贫困发生率持续下降,贫困人口大幅减少,2020年后将实现减贫转向;地理资本指数呈明显上升趋势,上升幅度高于黄河流域（0.078）和全国平均水平（0.067）,但仍受城乡居民收入和城市化水平较低,工业企业研发强度、贸易依存度、专利密度和技术市场水平较弱等方面的制约;该地区与黄河流域和全国比较发展差距在缩小,呈现区域收敛趋势,但欠发达的格局没有改变。在减贫转向和区域收敛的背景下,综合集成构建了该地区可持续减贫及由传统增长向高质量发展转型的路径模式。

Chromosomal ploidy manipulation is one of the means to create excellent germplasm. Triploid fish could provide an ideal sterile model for searching of a underlying mechanism of abnormality in meiosis. The complete understanding of the coding and noncoding RNAs regulating sterility caused by meiosis abnormality is still not well understood. By high-throughput sequencing, we compared the expression profiles of gonadal mRNA, long non-coding RNA (lncRNA), and microRNA (miRNA) at three different developmental stages between the diploid (XX) and triploid (XXX) female rainbow trout. These stages were gonads before differentiation (65 days post fertilisation, dpf), at the beginning of morphological differences (180 dpf) and showing clear difference between diploids and triploids (600 dpf), respectively. A majority of differentially expressed (DE) RNAs were identified, and 22 DE mRNAs related to oocyte meiosis and homologous recombination were characterized. The predicted miRNA-mRNA/lncRNA networks of 3 developmental stages were constructed based on the target pairs of DE lncRNA-miRNA and DE mRNA-miRNA. According to the networks, meiosis-related gene of ccne1 was targeted by dre-miR-15a-5p_R + 1, and 6 targeted DE lncRNAs were identified. Also, qRT-PCR was performed to validate the credibility of the network. Overall, this study explored the potential interplay between coding and noncoding RNAs during the gonadal development of polyploid fish. The mRNA, lncRNA and miRNA screened in this study may be helpful to identify the functional elements regulating fertility of rainbow trout, which may provide reference for character improvement in aquaculture.Copyright © 2018. Published by Elsevier Inc.

The mottled skate, Beringraja pulchra is one of the commercially important fishes in the market today. However, B. pulchra identification methods have not been well developed. The current study reports a novel real-time PCR method based on TaqMan technology developed for the genetic identification of B. pulchra. The mitochondrial cytochrome oxidase subunit 1 (COI) nucleotide sequences of 29 B. pulchra, 157 skates and rays reported in GenBank DNA database were comparatively analyzed and the COI sequences specific to B. pulchra was identified. Based on this information, a system of specific primers and Minor Groove Binding (MGB) TaqMan probe were designed. The assay successfully discriminated in 29 specimens of B. pulchra and 27 commercial samples with unknown species identity. For B. pulchra DNA, an average Threshold Cycle (Ct) value of 19.1±0.1 was obtained. Among 27 commercial samples, two samples showed average Ct values 19.1±0.0 and 26.7±0.1, respectively and were confirmed to be B. pulchra based on sequencing. The other samples tested showed undetectable or extremely weak signals for the target fragment, which was also consistent with the sequencing results. These results reveal that the method developed is a rapid and efficient tool to identify B. pulchra and might prevent fraud or mislabeling during the distribution of B. pulchra products. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The U.S. Food and Drug Administration is responsible for ensuring that the nation's food supply is safe and accurately labeled. This task is particularly challenging in the case of seafood where a large variety of species are marketed, most of this commodity is imported, and processed product is difficult to identify using traditional morphological methods. Reliable species identification is critical for both foodborne illness investigations and for prevention of deceptive practices, such as those where species are intentionally mislabeled to circumvent import restrictions or for resale as species of higher value. New methods that allow accurate and rapid species identifications are needed, but any new methods to be used for regulatory compliance must be both standardized and adequately validated. "DNA barcoding" is a process by which species discriminations are achieved through the use of short, standardized gene fragments. For animals, a fragment (655 base pairs starting near the 5' end) of the cytochrome c oxidase subunit 1 mitochondrial gene has been shown to provide reliable species level discrimination in most cases. We provide here a protocol with single-laboratory validation for the generation of DNA barcodes suitable for the identification of seafood products, specifically fish, in a manner that is suitable for FDA regulatory use.

We present the latest version of the Molecular Evolutionary Genetics Analysis (Mega) software, which contains many sophisticated methods and tools for phylogenomics and phylomedicine. In this major upgrade, Mega has been optimized for use on 64-bit computing systems for analyzing larger datasets. Researchers can now explore and analyze tens of thousands of sequences in Mega The new version also provides an advanced wizard for building timetrees and includes a new functionality to automatically predict gene duplication events in gene family trees. The 64-bit Mega is made available in two interfaces: graphical and command line. The graphical user interface (GUI) is a native Microsoft Windows application that can also be used on Mac OS X. The command line Mega is available as native applications for Windows, Linux, and Mac OS X. They are intended for use in high-throughput and scripted analysis. Both versions are available from www.megasoftware.net free of charge.© The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A common assumption in multiple scientific applications is that the distribution of observed data can be modeled by a latent tree graphical model. An important example is phylogenetics, where the tree models the evolutionary lineages of a set of observed organisms. Given a set of independent realizations of the random variables at the leaves of the tree, a key challenge is to infer the underlying tree topology. In this work we develop Spectral Neighbor Joining (SNJ), a novel method to recover the structure of latent tree graphical models. Given a matrix that contains a measure of similarity between all pairs of observed variables, SNJ computes a spectral measure of cohesion between groups of observed variables. We prove that SNJ is consistent, and derive a sufficient condition for correct tree recovery from an estimated similarity matrix. Combining this condition with a concentration of measure result on the similarity matrix, we bound the number of samples required to recover the tree with high probability. We illustrate via extensive simulations that in comparison to several other reconstruction methods, SNJ requires fewer samples to accurately recover trees with a large number of leaves or long edges.

Since the first investigation 25 years ago, the application of genetic tools to address ecological and evolutionary questions in elasmobranch studies has greatly expanded. Major developments in genetic theory as well as in the availability, cost effectiveness and resolution of genetic markers were instrumental for particularly rapid progress over the last 10 years. Genetic studies of elasmobranchs are of direct importance and have application to fisheries management and conservation issues such as the definition of management units and identification of species from fins. In the future, increased application of the most recent and emerging technologies will enable accelerated genetic data production and the development of new markers at reduced costs, paving the way for a paradigm shift from gene to genome-scale research, and more focus on adaptive rather than just neutral variation. Current literature is reviewed in six fields of elasmobranch molecular genetics relevant to fisheries and conservation management (species identification, phylogeography, philopatry, genetic effective population size, molecular evolutionary rate and emerging methods). Where possible, examples from the Indo-Pacific region, which has been underrepresented in previous reviews, are emphasized within a global perspective.© 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

75.5% of products were identified as species outside the expected family. Six products were identified as containing multiple species from distinct families. Species from distinct families were verified in products of same brand for six groups. Identification of potentially toxic pufferfish species highlighted health concerns.

Over the span of a decade, genetic identification methods have progressively exposed the inadequacies of the seafood supply chain, revealing previously unrecognized levels of seafood fraud, raising awareness among the public, and serving as a warning to industry that malpractice will be detected. Here we present the outcome of the latest and largest multi‐species, transnational survey of fish labeling accuracy to date, which demonstrates an apparent sudden reduction of seafood mislabeling in Europe. We argue that recent efforts in legislation, governance, and outreach have had a positive impact on industry regulation. Coordinated, technology‐based, policy‐oriented actions can play a pivotal role in shaping a transparent, sustainable global seafood market and in bolstering healthier oceans.

The California golden trout Oncorhynchus mykiss aguabonita is one of three subspecies within the rainbow trout–redband trout complex endemic to the Kern River basin and historically restricted to Golden Trout Creek and the South Fork Kern River. Past allozyme studies have indicated that native populations of California golden trout in the Golden Trout Creek drainage may have become introgressed with rainbow trout alleles through interaction with hybrids of rainbow trout and California golden trout stocked into nearby headwater lakes that are connected to tributaries in the drainage. We used six microsatellites and a minisatellite marker to estimate the genetic diversity and levels of introgression in approximately 700 California golden trout taken from 23 locations in Golden Trout Creek, its tributaries, and surrounding lakes. Indications of introgression were found in all but one of the sampled Golden Trout Creek drainage locations, the lowest average levels (0–8%) occurring in the lower reaches of Golden Trout Creek. The highest levels (12–17%) were in the Cottonwood Lakes populations that have been used as California golden trout broodstock by the California Department of Fish and Game. Evidence of introgression was also found in fish sampled from the upper reaches of the South Fork Kern River. This suggests that past and present stocking policies and hybridization with introduced rainbow trout currently threaten the genetic integrity of California golden trout populations across all of their native range.

We characterize 20 single nucleotide polymorphism assays for evaluating hybridization between native golden trout subspecies (Oncorhynchus mykiss aguabonita and O. m. whitei) and introduced rainbow trout strains. These assays utilize the 5'-nuclease reaction, facilitating high-throughput genotyping of many individuals and making them useful in quantifying and monitoring introgression and potentially applicable to studies of other O. mykiss groups. Minor allele frequency differentials (δq) among native and introduced rainbow groups ranged from 0 to 1, with an average differential of 0.75 for both subspecies aguabonita and whitei relative to the hatchery rainbow trout strain.© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.