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1.
四川雅安常见住区蝇类密度监测   总被引:2,自引:0,他引:2  
根据全国常见住区蝇类密度监测课题组关于“全国常见住区蝇类密度监测实施计划”安排,雅安地区定力全国七个监测点之一,作者承担了这一任务。该项工作尚在继续进行中,现将1988年监测结果报道如下。  相似文献   
2.
Conceptual models are an integral facet of long-term monitoring programs. Proposed linkages between drivers, stressors, and ecological indicators are identified within the conceptual model of most mandated programs. We empirically evaluate a conceptual model developed for a regional aquatic and riparian monitoring program using causal models (i.e., Bayesian path analysis). We assess whether data gathered for regional status and trend estimation can also provide insights on why a stream may deviate from reference conditions. We target the hypothesized causal pathways for how anthropogenic drivers of road density, percent grazing, and percent forest within a catchment affect instream biological condition. We found instream temperature and fine sediments in arid sites and only fine sediments in mesic sites accounted for a significant portion of the maximum possible variation explainable in biological condition among managed sites. However, the biological significance of the direct effects of anthropogenic drivers on instream temperature and fine sediments were minimal or not detected. Consequently, there was weak to no biological support for causal pathways related to anthropogenic drivers’ impact on biological condition. With weak biological and statistical effect sizes, ignoring environmental contextual variables and covariates that explain natural heterogeneity would have resulted in no evidence of human impacts on biological integrity in some instances. For programs targeting the effects of anthropogenic activities, it is imperative to identify both land use practices and mechanisms that have led to degraded conditions (i.e., moving beyond simple status and trend estimation). Our empirical evaluation of the conceptual model underpinning the long-term monitoring program provided an opportunity for learning and, consequently, we discuss survey design elements that require modification to achieve question driven monitoring, a necessary step in the practice of adaptive monitoring. We suspect our situation is not unique and many programs may suffer from the same inferential disconnect. Commonly, the survey design is optimized for robust estimates of regional status and trend detection and not necessarily to provide statistical inferences on the causal mechanisms outlined in the conceptual model, even though these relationships are typically used to justify and promote the long-term monitoring of a chosen ecological indicator. Our application demonstrates a process for empirical evaluation of conceptual models and exemplifies the need for such interim assessments in order for programs to evolve and persist.  相似文献   
3.
Introduction: Human serum albumin (HSA) is a multifaceted protein with vital physiological functions. It is the most abundant plasma protein with inherent capability to bind to diverse ligands, and thus susceptible to various post-translational modifications (PTMs) which alter its structure and functions. One such PTM is glycation, a non-enzymatic reaction between reducing sugar and protein leading to formation of heterogeneous advanced glycation end products (AGEs). Glycated albumin (GA) concentration increases significantly in diabetes and is implicated in development of secondary complications.

Areas covered: In this review, we discuss in depth, formation of GA and its consequences, approaches used for characterization and quantification of GA, milestones in GA proteomics, clinical relevance of GA as a biomarker, significance of maintaining abundant levels of albumin and future perspectives.

Expert commentary: Elevated GA levels are associated with development of insulin resistance as well as secondary complications, in healthy and diabetic individuals respectively. Mass spectrometry (MS) based approaches aid in precise characterization and quantification of GA including early and advanced glycated peptides, which can be useful in prediction of the disease status. Thus GA has evolved to be one of the best candidates in the pursuit of diagnostic markers for prediction of prediabetes and diabetic complications.  相似文献   

4.
Recent reports illustrate deficiencies in knowledge about current conditions and long-term trends in population sizes of hundreds of African plants and animals’ species. In this commentary, I discuss the lack of standardized data for assessing and monitoring biodiversity in Africa. I present my own views on the causes for these knowledge and data gaps, their consequences for conservation, and future directions that could improve the current situation.There are many reasons for lack of standardized data including; ongoing conflicts and political instability in many biodiversity-rich countries; absence of regular and policy-driven monitoring programs; weak facilities; and irregular or insufficient funding. Existing biodiversity monitoring initiatives are often short-term, poorly-designed surveys, largely dependent on volunteer researchers or international partners, biased towards large “charismatic” animal species, and published in difficult-to-access outlets. Consequently, up-to-date and rigorous reports about conditions and trends of African biodiversity are limited, and conservation planning, comparative studies and accurate valuation of ecosystem services continue to be difficult.Urgent actions include: 1) commitments and support of local governments to implement effective conservation monitoring programs; 2) establishment of a network of carefully designed long-term and continent-wide monitoring initiatives for endangered species and biodiversity; and 3) involvement of universities, research centers, Non-Governmental Organizations (NGOs) and local communities in such monitoring efforts. Such actions could stimulate further in-depth studies and systematic analysis of the root causes and solutions for the decades-long African biodiversity knowledge gap. Examples of highly needed systematic analysis and documentation in the coming efforts towards filling up the biodiversity data gap in Africa should clearly define biodiversity data-deficiency by taxonomic groups and by countries.  相似文献   
5.
大型水母声学观测与评估技术研究进展   总被引:1,自引:0,他引:1  
20世纪末以来,世界多个海域频繁出现大型水母暴发现象,对海洋生态系统、海洋渔业、沿海工业和滨海旅游业带来了巨大的灾难。为了研究大型水母生态习性,进而揭示其暴发机理并进行灾害的预警防治,近些年来国内外学者开展了大量的采用网具、目视、水下摄像、声学技术、航空影像等多种手段的大型水母监测调查工作,其中使用声学技术对大型水母进行资源评估和行为跟踪目前在欧美、日本、韩国等渔业发达国家已经开展了相关应用,在资源评估、运动学规律等研究中展现出较好的观测效果和应用潜力。目前我国在大型水母声学观测研究应用领域鲜有文献报道,通过介绍国际上利用声学技术对大型水母进行资源调查与评估、空间分布监测、运动规律等研究成果,为今后我国开展大型水母声学调查研究提供理论基础和科学依据。通过本文的分析,建议可以借鉴国际上采用科学鱼探仪、高分辨率成像声呐、声学信标等方法对大型水母进行监测调查和资源评估的研究成果,结合实际情况将声学技术逐步研究并应用到我国大型水母资源调查与评估、自然生态习性研究、重点水域大型水母动态监测预警中去,完善我国大型水母监测调查体系。  相似文献   
6.
Occupancy is an important metric to understand current and future trends in populations that have declined globally. In addition, occupancy can be an efficient tool for conducting landscape-scale and long-term monitoring. A challenge for occupancy monitoring programs is to determine the appropriate spatial scale of analysis and to obtain precise occupancy estimates for elusive species. We used a multi-scale occupancy model to assess occupancy of Columbia spotted frogs in the Great Basin, USA, based on environmental DNA (eDNA) detections. We collected three replicate eDNA samples at 220 sites across the Great Basin. We estimated and modeled ecological factors that described watershed and site occupancy at multiple spatial scales simultaneously while accounting for imperfect detection. Additionally, we conducted visual and dipnet surveys at all sites and used our paired detections to estimate the probability of a false positive detection for our eDNA sampling. We applied the estimated false positive rate to our multi-scale occupancy dataset and assessed changes in model selection. We had higher naïve occupancy estimates for eDNA (0.37) than for traditional survey methods (0.20). We estimated our false positive detection rate per qPCR replicate at 0.023 (95% CI: 0.016–0.033). When the false positive rate was applied to the multi-scale dataset, we did not observe substantial changes in model selection or parameter estimates. Conservation and resource managers have an increasing need to understand species occupancy in highly variable landscapes where the spatial distribution of habitat changes significantly over time due to climate change and human impact. A multi-scale occupancy approach can be used to obtain regional occupancy estimates that can account for spatially dynamic differences in availability over time, especially when assessing potential declines. Additionally, this study demonstrates how eDNA can be used as an effective tool for improved occupancy estimates across broad geographic scales for long-term monitoring.  相似文献   
7.
为了解福岛核泄漏放射性核素对北太平洋公海渔场的后续性污染影响情况,于2013年8—11月在北太平洋公海渔场(40°—44° N、145°—160° E)采集柔鱼样品,利用超低本底HPGe γ 谱仪分析5种放射性核素.结果表明: 134Cs和110mAg未检测出高于本底值的比活度,而210Pb、137Cs和40K均有检出.其中210Pb在柔鱼体的比活度范围为0.99~7.60 Bq·kg-1,137Cs的比活度范围为最低检测限~0.37 Bq·kg-1,40K的比活度范围为46.00~107.00 Bq·kg-1.210Pb核素含量在柔鱼250~300 mm胴长组分布最高;在200~250和>400 mm胴长组中最低.137Cs含量在柔鱼200~250 mm胴长组中最高;在250~300和350~400 mm胴长组较低.40K核素含量在柔鱼250~300 mm胴长组中最高,在150~200 mm胴长组最低,总体分布比较均匀.3种核素在柔鱼的不同组织中含量不同,但均在内脏中含量最高.通过风险评估发现,北太平洋公海渔场所有检测的海洋生物的放射性核素含量值与基准值的熵值均未超过1,说明目前核辐射对该海域渔业资源的影响暂无大风险.研究可为福岛核事故对海洋环境生态影响及公众健康危害评估提供理论依据.  相似文献   
8.
Alternative ORFs (AltORFs) are unannotated sequences in genome that encode novel peptides or proteins named alternative proteins (AltProts). Although ribosome profiling and bioinformatics predict a large number of AltProts, mass spectrometry as the only direct way of identification is hampered by the short lengths and relative low abundance of AltProts. There is an urgent need for improvement of mass spectrometry methodologies for AltProt identification. Here, we report an approach based on size-exclusion chromatography for simultaneous enrichment and fractionation of AltProts from complex proteome. This method greatly simplifies the variance of AltProts discovery by enriching small proteins smaller than 40 kDa. In a systematic comparison between 10 methods, the approach we reported enabled the discovery of more AltProts with overall higher intensities, with less cost of time and effort compared to other workflows. We applied this approach to identify 89 novel AltProts from mouse liver, 39 of which were differentially expressed between embryonic and adult mice. During embryonic development, the upregulated AltProts were mainly involved in biological pathways on RNA splicing and processing, whereas the AltProts involved in metabolisms were more active in adult livers. Our study not only provides an effective approach for identifying AltProts but also novel AltProts that are potentially important in developmental biology.  相似文献   
9.
For decades, the bio-duck sound has been recorded in the Southern Ocean, but the animal producing it has remained a mystery. Heard mainly during austral winter in the Southern Ocean, this ubiquitous sound has been recorded in Antarctic waters and contemporaneously off the Australian west coast. Here, we present conclusive evidence that the bio-duck sound is produced by Antarctic minke whales (Balaenoptera bonaerensis). We analysed data from multi-sensor acoustic recording tags that included intense bio-duck sounds as well as singular downsweeps that have previously been attributed to this species. This finding allows the interpretation of a wealth of long-term acoustic recordings for this previously acoustically concealed species, which will improve our understanding of the distribution, abundance and behaviour of Antarctic minke whales. This is critical information for a species that inhabits a difficult to access sea-ice environment that is changing rapidly in some regions and has been the subject of contentious lethal sampling efforts and ongoing international legal action.  相似文献   
10.
Evidence‐based practice is not possible without an evidence base. Guldemond et al. confuse our attempt at assessing the status of the evidence base of restoration programs in South Africa with attempting to assess whether restoration is evidence‐based. While we fully agree with them that there is a need to assess whether practitioners use evidence in their decision‐making, we assert that use of evidence is the last step in the evidence‐based approach. It is preceded by the generation (and documentation) of evidence through baseline condition assessment, proper goal setting, sound monitoring of the impacts of the chosen intervention as well as effective dissemination of resulting evidence. To answer the question whether restoration is evidence‐based would require the assessment of all stages from generation to use. We chose to start at the beginning, a logical place to start.  相似文献   
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