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11.
Accumulating evidence suggests that a single microRNA (miRNA) locus can generate a series of sequences during miRNA maturation process. These multiple sequences, called miRNA variants, or isomiRs, have different lengths and different 5′ and 3′ ends. Some of these isomiRs are detected as varied nucleotides and 3′ additional non-template nucleotides. As physiological miRNA isoforms, they have drawn attention for possible regulatory biological roles. The present work mainly reviews miRNA/isomiR biogenesis, isomiR expression patterns, and functional and evolutionary implications, especially between isomiRs from homologous and clustered miRNA loci. The phenomenon of multiple isomiRs and their biological roles indicates that analysis performed at the miRNA and isomiR levels should be included in miRNA studies. This may enrich and complicate miRNA biogenesis and coding–non-coding RNA regulatory networks.  相似文献   
12.
长岛自然保护区生态系统维护的条件价值评估   总被引:4,自引:0,他引:4  
长岛自然保护区是典型的海岛自然保护区,迅速发展的捕捞业、养殖业和旅游业不可避免地引起环境污染和资源过度利用等问题,使长岛生态系统可持续发展面临严峻挑战。采用支付卡式的条件价值法,调查并估算了2013年居民和游客对维护长岛自然保护区生态系统的支付意愿,并与2008年的研究结果比较以检验条件价值法的可靠性。结果显示,2013年居民和游客人均最大支付意愿分别为203.77和257.26元/a,分别比2008年增长了7.9%和21.7%。两次支付意愿调查结果的相同点在于居民或游客对各个投标额愿意支付的人数比例在不同年份分布趋势基本一致,不同点在于愿意支付的人数比例明显增加。前者体现在居民对各个投标额的选择比较集中,而游客的选择比较分散;后者表现为居民和游客愿意支付的人数比例增长率分别为20.5%和19.1%。结果表明,采用条件价值法评估长岛自然保护区居民和游客对生态系统维护的支付意愿结果可靠,其评估结果主要受经济收入和环境保护意识的影响。因此,当地政府应在发展经济的基础上,加强对生态环境保护的宣传和教育。  相似文献   
13.
Industrial harbours are a complex interface between environmental, economic and social systems. Trying to manage the social and economic needs of the community while maintaining the integrity of environmental ecosystems is complicated, as is the identification and evaluation of the various factors that underpin the drivers of economic, community and resource condition. An increasingly popular strategy to deal with the identification and evaluation challenges in complex human-environmental systems is to use a report card system which can be used as a summary assessment tool to monitor the health of aquatic ecosystems. To date though these have largely focused on environmental factors, and it is only very recently that attempts are being made to include social, cultural and economic indicators. There has been limited consensus in the selection of social and economic indicators applied in different aquatic report cards but as recreation is such an important activity, typically some measure of recreation benefit is included. However, there has been no commonality in the measures applied to assess its performance as an economic indicator.This paper is focused on the assessment of recreational benefits as an indicator of economic value in the report card for Gladstone Harbour in Queensland, Australia. It is the first aquatic health report card to include an assessment of the nonmarket value of recreation which makes it a more comprehensive indicator of economic value compared to other report cards based on measures of employment, participation or expenditure. There have now been three consecutive years of reporting (2014–2016) of the Gladstone Harbour report card, and the results indicate that the recreation index appears to be effective in monitoring changes over time.  相似文献   
14.
PurposeThe geriatric population is especially vulnerable to coronavirus disease (COVID-19) and its potential complications. We sought to analyze the incidence of cardiological complications in an elderly population hospitalized for COVID-19.MethodsA prospective observational longitudinal that included patients ≥75 years of age with diagnosis of COVID-19 admitted to the Geriatric Department from March to May 2020. Epidemiological, geriatric, clinical and laboratory test variables were collected. Cardiovascular events, including de novo atrial fibrillation (AF), acute coronary syndrome (ACS), congestive heart failure (CHF), pulmonary embolism and in-hospital death, were documented. A follow-up was carried out at 12 months through a telephone interview as well as using electronic medical records, collecting cardiac events and mortality.Results305 patients were included; 190 (62.3%) were female, with median age of 87 years (interquartile range (82–91)). More than half of the patients had a history of cardiac disease, with AF being the most common and affecting 85 (27.9%) patients. During hospitalization, 112 (36.7%) patients died. Eighty-nine (29.2%) patients presented cardiac complications. Acute heart failure was the most prevalent (46; 15.1%), followed by new-onset AF (20; 6.5%), pulmonary embolism (17; 5.6%), and ACS (5; 1.6%). Patients with cardiac complications had a longer hospital stay (p < 0.001). During follow-up, 29 (15.1%) died, and 40 (20.8%) patients had a cardiovascular event being CHF the most prevalent complication (16.7%).ConclusionThe incidence of cardiovascular complications in geriatric patients is high and is associated with a longer hospital stay. CHF was the most frequent event, followed by AF.  相似文献   
15.
利用SRAP标记对来自海南省的28份旱稻种质进行了亲缘关系分析。从255对引物组合中筛选出46对扩增条带清晰、多态性高的引物组合,并选用其中的18对引物组合对28份材料进行SRAP扩增,共扩增出180个条带,其中多态性条带160条,多态性比率为87.75%,平均每对引物组合产生10个条带和8.9个多态性条带。并且,运用UPMGA方法进行的聚类分析结果表明,供试旱稻种质的遗传相似系数范围为0.687 0-0.921 2,在遗传相似系数0.687 0处分为两大类群,第I类群全部为海南山栏稻种质,第Ⅱ类群为海南地方旱稻坡压和本研究组自育旱稻品种。对海南旱稻地方品种的划分表明,山栏稻种质间亲缘关系较近,海南地方旱稻坡压可能与籼型水稻种质具有一定的遗传相似性。此外,还构建了28份海南省旱稻种质的SRAP标记分子身份证,可为山栏稻种质的遗传亲缘关系,种质鉴定及新品种选育等方面提供依据。  相似文献   
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17.
Phytostabilization is a promising option for the remediation of metal contaminated soils which requires the implementation of long-term monitoring programs. We here propose to incorporate the paradigm of “adaptive monitoring”, which enables monitoring programs to evolve iteratively as new information emerges and research questions change, to metal phytostabilization. Posing good questions that cover the chemical, toxicological and ecological concerns associated to metal contaminated soils is critical for an efficient long-term phytostabilization monitoring program. Regarding the ecological concerns, soil microbial parameters are most valuable indicators of the effectiveness of metal phytostabilization processes in terms of recovery of soil health. We suggest to group soil microbial parameters in higher-level categories such as “ecological attributes” (vigor, organization, stability) or “ecosystem services” in order to facilitate interpretation and, most importantly, to provide long-term phytostabilization monitoring programs with the required stability through time against changes in techniques, methods, interests, etc. that will inevitably occur during the monitoring program. Finally, a Phytostabilization Monitoring Card, based on both ecological attributes and ecosystem services, for soil microbial properties is provided.  相似文献   
18.
绿黄色光二极管(LED)附加在塑胶杯和胶片捕捉器可增加捕捉实验室和温室中昆虫的数量。附加有530nm绿黄色LED的塑胶杯捕捉器比没有附加的捕捉到更多的Trialeurodes vaporariorum(Westwood)和Bemisia tabaci(Gennadius)B生态型。在温室中昆虫笼以四季豆和棉花试验,附加有530nm绿黄色LED的黄色胶片(YC)和透明塑胶片(CS)分别缩写为LED—YC和LED—CS)比每一种没有附加的捕捉器捕捉到更多的T.vaporariorum,B.tabaci B生态型,Ahis gossypii(Glover)和Bradysia coprophila(Lintner)成虫。绿黄色LED—YC在温室中有用为监测和控制的潜在性。  相似文献   
19.
《IRBM》2020,41(2):88-93
BackgroundIn the modern era, researchers are facing a big challenge in diagnosing autism disorders. According to the Center for Disease Control and Prevention 2014 report, the prevalence of autism among children in the United States is approximately 1 out of 88 children; whereas, in South Korea, the prevalence is 1 out of 38. In India, most of the children with autism are yet to be diagnosed partly due to the lack of self-screening test compared to the other countries. Currently, no data is available for analyzing the prevalence of autism in India. In order to improve the behavior, the social interaction, and the verbal communication of these children, scientists are using various kinds of teaching methods.ObjectivesThe objectives of this work were to screen the level of autism among school children using Gilliam Autism Rating Scale (GARS-2) questionnaire and evaluate the effects of various teaching methods on social behavior of school children with autism.Methods and resultsNinety children in the age group between 3 – 16 years from three schools (S1 – 30, S2 – 30 and S3 – 30) with autism are participated in this study. In S1, the autistic children are trained with horseback riding and yoga therapy; whereas in the S2, the children are trained with normal teaching using blackboard and in the S3, the children are trained with cue cards. The GARS-2 questionnaire was used for assessing the communication, the stereotype behavior and the social interaction with the help of parents or the caregivers.ConclusionResults of our study revealed that raw and the standard scores of stereotyped behaviors was notably (p<0.05) low in S1 school children when collated with the other two (S2 and S3) schools. Similarly, the raw and the standard score of communication, the socially interaction sub-score was notably (p<0.05) low for the children in S3 when collated with the children in the other two schools. The study concluded that the horseback riding, the yoga therapy and the cue cards-based teaching methods improve the stereotyped behavior, increase concentration power and also helps in maintaining the children's mind stability.  相似文献   
20.
Teaching biological evolution can be difficult on a number of levels, be it student confusion arising from prior conceptions and the controversy surrounding evolution, or simply because the material is complex. Games and simulations can help to convey complex topics and also to increase variety in teaching methods. Here I describe a card game that can be used to teach the advanced topic of protected polymorphism in higher education settings. Protected polymorphism is allelic variation resulting from negative frequency-dependent selection; when the fitness of an allele increases when it becomes rare, the allele will be ‘protected’ from extinction. Negative frequency-dependent selection is proposed to maintain genetic variation in nature, which is required for evolution by natural selection. Protected polymorphisms primarily play a role in biological interactions, such as immune systems, plant-pathogen interactions, sexual selection and predator-prey interactions. The card game described here uses plant pollination alleles as an example. The game is played using eleven stocks of traditional playing cards per group of about six students. Specific topics addressed include negative frequency-dependent selection, polyploidy, dominance, selfing and inbreeding depression.  相似文献   
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