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101.
胡仁传  周迎  董亦非  罗斌圣 《广西植物》2023,43(8):1428-1436
生物多样性是人类赖以生存的物质基础,目前对生物多样性的保护主要通过建立自然保护区来进行。保护小区作为我国现有自然保护区体系的一个重要补充,是联通动植物破碎化的栖息地,维护生态系统完整性的重要手段。该文通过文献研究和实地调查等方式对以社区为主体的渠楠保护小区的组织架构、制度建设、日常工作以及初步成效等进行了系统的整理和分析。结果表明:(1)渠楠保护小区以“自建、自筹、自管、自受益”为指导思想进行建设,采取“平等议事、民主协商”为主的方式进行管理,得到了当地社区居民的认可和拥护,并得到了当地政府和外界的承认和支持。(2)保护小区的成立、建设和发展,不仅提高了社区居民的保护意识和周边动植物种群数量及多样性,还改善了渠楠社区的生活环境,丰富了社区居民的精神文化,为当地的生物多样性和传统文化的保护做出了积极贡献。该文还探讨了以社区为主体的保护小区建设中存在的隐患,并提出可行性建议,以期为我国生物多样性保护及其他保护小区的发展提供参考。  相似文献   
102.
An unexpected and interesting intramolecular side reaction occurred during the attempted synthesis of glycosyl cyanides upon treatment of 1-O-acetyl-3-azido-3-deoxyallose derivatives with TMSCN and different Lewis acids. Exo-1,2-O-cyanoalkylidene derivatives formed by neighboring group participation and attack of cyanide underwent, after Lewis-acid mediated isomerization to the endo-isomer, intramolecular azide-cyanide cycloaddition leading to the formation of tetrazoles embedded in bridged tetracyclic ring systems. The efficiency of cycloaddition is dependent on the ring structure of the sugar (pyranose or furanose). Of the studied molecules, 3-azido-1,2-O-cyanoethylidene-3-deoxy-allopyranose provides the most suitable scaffold for intramolecular [2+3] cycloaddition under exceptionally mild conditions. Our results highlight the capability of carbohydrates to act as scaffolds for the precise positioning of functional groups productive for a specific chemical reaction.  相似文献   
103.
Social participation, as far as children and youth are concerned, stands as one of the rights of children formalized by the Convention on the Rights of the Child. The present work is an attempt to contribute to the discussion on the ways whereby this right can be implemented, by raising the issue that children and youth constructively interpret social differences as a main feature of cities by providing explanations of social inequalities and their remedial mechanisms. Three case studies based on an action research invervention in three different institutions are presented. The analysis of focal group discussions with children and youth highlight their perspectives about life in the city: the city that they lived in and the city as they would like it to be demonstrating how children's and youth's views can provide a deep and critical understanding of their own society and the ways to change it.  相似文献   
104.
Yang F  He H  Du Y  Lü M 《Carbohydrate research》2002,337(13):1165-1169
In an effort to prepare complex oligosaccharide derivatives, a series of unexpected alpha glycosides were predominantly formed in the presence of neighboring group participation using imidates or thioglycosides as glycosyl donors under standard glycosylation conditions. The observations are especially suitable in the case of alpha-(1-->3) glycosidic bond formation.  相似文献   
105.
The essay examines the role of The Ontario Society for Services to the Indo-Caribbean Community [OSSICC], a historic organization that sought to assert the dignity and re-discover the identity of Indo-Caribbean persons as a fragment of the Caribbean diaspora in Toronto, Canada. While it points to the achievement in representing the interests of its members for symbolic cultural recognition, it underscored the limitations in the political arena for empowerment, power sharing, and equality in employment opportunities and for an equitable share of the resources of the state. Further, it describes how the ethnic conflict in the homeland persisted in the new site of the diaspora, about lost opportunities for healing, and about inter-generational discontinuities in the reconstruction of the Caribbean self. On a larger scale, the article is about membership and citizenship in the new homeland of the diaspora, its seductions and betrayals in the new frontier of Canadian multiculturalism.  相似文献   
106.
The number of waterfowl hunters in the United States has declined since the 1980s despite relatively abundant waterfowl populations and liberal hunting regulations. Programs focused on recruiting, retaining, and reactivating (R3) waterfowl hunters have become important to avoid further losses in traditional revenue for habitat management and protection and political support for waterfowl conservation and management. We focus on 4 waterfowl hunter population vital rates (i.e., recruitment rate, retention probability, license purchase probability, realized population growth rate), which can be used to improve the effectiveness of waterfowl hunter R3 activities and initiatives by providing a deeper understanding of waterfowl hunter population dynamics to determine who programs should target, where programs should be targeted, and finally the evaluation of programs. To do so, we analyzed Nebraska state electronic license data from 2012–2019 using Pradel survival and recruitment models in a mark-recapture framework. Female waterfowl hunter recruitment was higher than males; however, retention and license purchase probabilities were lower. Recruitment was highest in younger generations and retention highest in older generations. License purchase probabilities were highest among those in the oldest and youngest generations. The availability of hunting opportunity increased license purchase probabilities but had a minimal influence on retention and no association with recruitment. There were weak relationships between rurality and recruitment, and retention and license purchase probabilities. Finally, belonging to Ducks Unlimited was positively associated with higher license purchase and retention probabilities. Targeting an increase in license purchase probability by promoting social support for hunters through conservation organization membership should be a focus of waterfowl hunter R3 efforts to have the greatest influence on increasing waterfowl hunter participation.  相似文献   
107.
Objective: To describe the relationship between obesity class and workforce participation and the influence of demographic, socioeconomic, and comorbid disease states on this relationship using population‐based Canadian data. Research Methods and Procedures: Responses from 73, 531 adults surveyed in the Canadian Community Health Survey 2000 to 2001 who provided complete information regarding variables of interest were analyzed. Workforce participation was defined as individuals reporting that they held and were present at a job or business in the week before survey administration. The association between obesity and workforce participation was explored using logistic regression after adjusting for demographic, socioeconomic, and obesity‐related comorbidities. Results: In univariate analysis, obese individuals had lower odds of participating in the workforce. In the fully adjusted model, increasing obesity was associated with decreasing odds of workforce participation, with Class I, II, and III obesity having odds ratios (95% confidence interval) of 0.94 (0.89 to 0.99), 0.85 (0.77 to 0.94), and 0.66 (0.57 to 0.78), respectively. Obese individuals were also less likely to be employed and more likely to be absent from work. Discussion: Obesity is associated with lower workforce participation. This association appears to be independent of associated comorbidity and sociodemographic factors. These results indicate that the economic impact of obesity alone on workforce productivity is larger than previous reports suggest.  相似文献   
108.
基于农牧民响应的阿拉善荒漠复合生态系统管理研究   总被引:1,自引:0,他引:1  
贾举杰  王也  刘旭升  李锋  张象枢 《生态学报》2017,37(17):5836-5845
内蒙古草原是我国华北、东北地区的重要生态屏障,阿拉善盟的生态环境直接影响到首都和华北地区的生态安全。以内蒙古自治区阿拉善盟1980—2014年年际人口、温度、家畜量及农作物面积变化为基础,2015年9月—2016年4月,采用入户访问和半结构访谈的方式,对阿拉善盟3个旗的16个自然村进行问卷调查,分析被访问对象对本区域政府-NGO-农牧民等利益相关者多方参与的荒漠化治理模式的响应和认知,以及对未来生态环境治理的建议和意愿,以期为荒漠复合生态系统的建设提供管理建议。运用The R Programming Language中的探索性因子分析法进行数据分析,结果表明:(1)自然因素(干旱、虫鼠害等)和人为因素(工业增加、城市扩张、农业增加等)是基于访谈对象认知的本区域环境恶化的主要原因。(2)多年来,政府部门主导的生态补偿和生态移民等政策的实施,政府、NGO、农牧民的群策群力以及农牧民环保意识的增强等综合因素是研究区环境局部恢复的主要原因。未来,建议加快生态建设步伐,构建以"政府主导,社会行动,社区参与"为主导的荒漠化治理模式是阿拉善环境保护和可持续发展的需要。  相似文献   
109.
杨希  高强  梁鹏  何慧 《微生物学通报》2021,48(10):3910-3922
微生物学属于生命科学的重要分支,是生物、食品科学、临床医学等大学专业一门重要的基础课。该课程综合性强、知识涉及面广,所以如何有效调动学生的学习兴趣将直接影响课堂效果。为达到良好的教学效果,教师可在微生物学教学过程中综合运用多种方式提高学生学习兴趣与学习质量。因此,我们采用“趣味教学法”进行教学设计,并针对连续3个不同年级的相同专业班级做出教学改革,通过学生期末闭卷成绩、过程考核(签到率、课堂参与度、注意力集中程度等)成绩与学生反馈评语对教学成果进行验证。结果表明,采用“趣味教学法”进行教学改革的班级学生期末闭卷成绩中不及格率低于未改革的班级,“良好”与“优秀”学生比例均高于未改革的班级,过程考核成绩远高于未改革的班级,说明“趣味教学法”教学改革有效调动了学生的学习兴趣。我们认为,在大学微生物学课堂上,教师可在教学设计中适当引入趣味教学内容并适时展开,有助于改善教学气氛,调动学生学习积极性与主动性,提高教学质量。  相似文献   
110.
BackgroundPatients with advanced heart failure may benefit from palliative care, including advance care planning (ACP). ACP, which can include referral back to the general practitioner (GP), may prevent unbeneficial hospital admissions and interventional/surgical procedures that are not in accordance with the patient’s personal goals of care.AimTo implement ACP in patients with advanced heart failure and explore the effect of ACP on healthcare utilisation as well as the satisfaction of patients and cardiologists.MethodsIn this pilot study, we enrolled 30 patients with New York Heart Association class III/IV heart failure who had had at least one unplanned hospital admission in the previous year because of heart failure. A structured ACP conversation was held and documented by the treating physician. Primary outcome was the number of visits to the emergency department and/or admissions within 3 months after the ACP conversation. Secondary endpoints were the satisfaction of patients and cardiologists as established by using a five-point Likert scale.ResultsMedian age of the patients was 81 years (range 33–94). Twenty-seven ACP documents could be analysed (90%). Twenty-one patients (78%) did not want to be readmitted to the hospital and subsequently none of them were readmitted during follow-up. Twenty-two patients (81%) discontinued all hospital care. All patients who died during follow-up (n = 12, 40%) died at home. Most patients and cardiologists indicated that they would recommend the intervention to others (80% and 92% respectively).ConclusionACP, and subsequent out-of-hospital care by the GP, was shown to be applicable in the present study of patients with advanced heart failure and evident palliative care needs. Patients and cardiologists were satisfied with this intervention.  相似文献   
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