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51.
基于扎根理论的社区参与国家公园建设与管理的机制研究   总被引:3,自引:0,他引:3  
何思源  魏钰  苏杨  闵庆文 《生态学报》2021,41(8):3021-3032
大量研究表明自然保护地周边社区居民对保护地的态度是影响社区参与保护,实现保护地管理目标的主要因素,由此建立了"认知-态度-参与"的行为逻辑。中国国家公园体制建设希望进一步推进社区与保护地的关系,全面提升自然保护管理效率,也建立在对这一行为逻辑的认同之上。为验证社区认知与行为的关系,并为促进不同利益相关者参与国家公园建设与管理提供科学支持,研究试图分析武夷山国家公园体制试点区社区居民的国家公园的"认知-态度-参与"的行为逻辑以揭示社区参与国家公园建设与管理的深层机制。与一般研究不同在于,本研究是针对正在建设中的国家公园,使得本地利益相关方的态度有机会影响国家公园建设进程。为获得社区"认知-态度-参与"核心观念,探索社区参与的过程和方式,提出促进社区参与的方法,研究采用扎根理论这一质性研究方法,基于对本地利益相关者采用半结构化开放问题的深度访谈,归纳出概念与范畴,形成社区参与国家公园建设与管理的理论。研究首先形成45个概念与13个范畴,通过范式模型研究发现,稳定资源使用权利、引导社区参与决策、保障社区发展权利、创新社区产业模式、提高个体适应能力、降低政策风险影响等六个主范畴能够解释社区居民对国家公园的认知-态度-参与这一行为逻辑。通过归纳主范畴,研究进一步提炼出社区参与国家公园建设与管理的理论核心在于社区自然资源管理的自主性、创新性与适应性,其内在机制在于社区参与是一个自主性提高的动态过程,需要通过保障社区生计资源禀赋来实现长期的价值转化,最终使其成为社会-生态系统适应性治理的组成部分。在理论阐释基础上,研究提出从改善社区认知、提升社区参与角度推进国家公园建设的路径。研究也指出,所提出的社区参与机制理论能够提炼量化指标评价社区参与,追踪武夷山国家公园体制试点进程。  相似文献   
52.
气候变暖已经引起全球降水格局改变。土壤呼吸作为陆地生态系统向大气释放CO2最大的碳库,对降水变化的响应将进一步影响碳循环,从而对全球气候变化产生反馈。尽管以往已有大量关于土壤呼吸与降水变化关系的相关研究,但存在较大争议。因此,亟待进一步深入探究土壤呼吸对降水改变的响应。基于此,研究Meta分析方法,整合了来自Web of Science 英文数据库和中国知网文献数据库(CNKI)的284篇已发表的论文和367组数据,进而分析全球中低纬度地区土壤呼吸对降水改变的响应。研究结果表明,土壤呼吸对降水改变的响应呈现出非对称特征,降水量增加能够提高16.7%的土壤呼吸,而降水量减少则会抑制17.88%的土壤呼吸。研究还发现,不同生态系统和气候区域的土壤呼吸对降水改变的响应存在较大差别。其中,降水量增加能够提高草地生态系统22%的土壤呼吸,比森林生态系统土壤呼吸高出12%;而降水量减少则会削弱草地生态系统28%的土壤呼吸,这要比森林生态系统土壤呼吸还高16%。与湿润地区相比,降水量的增加对干旱地区土壤呼吸的促进作用更加明显。而降水量的减少对干旱地区和湿润地区土壤呼吸的影响均无显著差异。此外,本研究也证实了土壤呼吸对不同降水强度和年限的响应也存在差异。在不同降水强度上,无论增加降水还是减少降水,重度增减雨的土壤呼吸均改变最大,即:重度增减雨(>75%)>中度增减雨(25% -75%) >轻度增减雨(<25%);在不同降水年限上,长期增雨对土壤呼吸的促进作用尤为突出,但长期减雨对土壤呼吸影响无显著差异。研究结果可为未来气候情景下陆地生态系统土壤呼吸变化的准确预测以及模型模拟和改进提供重要的科学依据和理论基础。  相似文献   
53.
The use of amorphous solid dispersions to improve the bioavailability of active ingredients from the BCS II and IV classifications continues to gain interest in the pharmaceutical industry. Over the last decade, methods for generating amorphous solid dispersions have been well established in commercially available products and in the literature. However, the amorphous solid dispersions manufactured by different technologies differ in many aspects, primarily chemical stability, physical stability, and performance, both in vitro and in vivo. This review analyzes the impact of manufacturing methods on those properties of amorphous solid dispersions. For example, the chemical stability of drugs and polymers can be influenced by differences in the level of thermal exposure during fusion-based and solvent-based processes. The physical stability of amorphous content varies according to the thermal history, particle morphology, and nucleation process of amorphous solid dispersions produced by different methods. The in vitro and in vivo performance of amorphous formulations are also affected by differences in particle morphology and in the molecular interactions caused by the manufacturing method. Additionally, we describe the mechanism of manufacturing methods and the thermodynamic theories that relate to amorphous formulations.  相似文献   
54.
Dendritic cells (DCs) play a predominant role in initiating cell immune responses. Here we generated a DC-targeting lentiviral vector (LVDC-UbHBcAg-LIGHT) and evaluated its capacity to elicit HBV-specific cytotoxic T lymphocyte (CTL) responses. DC-SIGN-mediated specific transduction using this construct was confirmed in DC-SIGN-expressing 293T cells and ex vivo-cultured bone marrow cells. LVDC-UbHBcAg-LIGHT-loaded DCs were highly effective in inducing HBV-specific CTLs. Mechanistic studies demonstrated autophagy blocking led to a significant increase in apoptosis and obvious inhibition of CD8 + T cells entry into S-phase, correspondingly attenuated LVDC-UbHBcAg-LIGHT-loaded DC-induced T cell responses. This observation was supported by accumulation of pro-apoptotic proteins and the main negative cell cycle regulator-CDKN1B that otherwise would be degraded in activated T cells where autophagy preferentially occured. Our findings revealed an important role of autophagy in the activation of T cells and suggested LVDC-UbHBcAg-LIGHT may potentially be used as a therapeutic strategy to combat persistent HBV infection with higher security.  相似文献   
55.
Aqueous‐solution‐processed solar cells (ASCs) are promising candidates of the next‐generation large‐area, low‐cost, and flexible photovoltaic conversion equipment because of their unique environmental friendly property. Aqueous‐solution‐processed polymer/nanocrystals (NCs) hybrid solar cells (AHSCs) can effectively integrate the advantages of the polymer (e.g., flexibility and lightweight) and the inorganic NCs (e.g., high mobility and broad absorption), and therefore be considered as an ideal system to further improve the performance of ASCs. In this work, double‐side bulk heterojunction (BHJ), in which one BHJ combines the active material with electron transport material and the other combines the active material with hole transport material, is developed in the AHSCs. Through comparing with the single‐side BHJ device, promoted carrier extraction, enhanced internal quantum efficiency, extended width of the depletion region, and prolonged carrier lifetime are achieved in double‐side BHJ devices. As a result, power conversion efficiency exceeding 6% is obtained, which breaks the bottleneck efficiency around ≈5.5%. This work demonstrates a device architecture which is more remarkable compared with the traditional only donor–acceptor blended BHJ. Under conservative estimation, it provides instructive architecture not only in the ASCs, but also in the organic solar cells (SCs), quantum dot SCs, and perovskite SCs.  相似文献   
56.
王思元  曾琦琛 《生物信息学》2018,25(10):104-109
柏林墙是柏林近代史上重要的一段政治事件遗迹与历史见证。从1990年6月至今,柏林政府对柏林墙遗址地区进行了不同层面的保护和开发。梳理了柏林墙与柏林城市发展的关系,从政府工作、遗址构筑物与户外公共空间3个方面,研究了柏林墙遗址地区的保护与规划内容,认为针对柏林墙遗址地区,德国政府及人民对历史予以足够的尊重,以政府为主导的多维度、持续性的规划工作对遗址地区起到了重要的保护作用。灵活多样、高品质的公共空间营造方式与丰富的纪念性活动,使得衰败的地区得以激活和复兴,为中国遗址地区保护与规划设计提供借鉴。  相似文献   
57.
58.
Histone lysine specific demethylase 1 (LSD1) is overexpressed in diverse hematologic disorders and recognized as a promising target for blood medicines. In this study, molecular docking-based virtual screening united with bioevaluation was utilized to identify novel skeleton of 5-arylidene barbiturate as small-molecule inhibitors of LSD1. Among the synthesized derivatives, 12a exhibited reversible and potent inhibition (IC50?=?0.41?μM) and high selectivity over the MAO-A and MAO-B. Notably, 12a strongly induced differentiation effect on acute promyelocytic leukemia NB4 cell line and distinctly escalated the methylation level on histone 3 lysine 4 (H3K4). Our findings indicate that 5-arylidene barbiturate may represent a new skeleton of LSD1 inhibitors and 12a deserve as a promising agent for the further research.  相似文献   
59.

Objective

The aim of this study was to determine whether a AOI strategy on non-ventilated lung could reduce the regional and systemic proinflammatory cytokine and oxidative stress response associated with esophagectomy, and to evaluate whether AOI can be used as a novel lung protective ventilation strategy. Its impact on oxygenation after OLV, surfactant protein A, B, C (SP-A, B, C), postoperative hospital stay and postoperative pulmonary complications (PPCs) was also evaluated.

Methods

Fifty-four adults (ASA II-III) undergoing esophagectomy with OLV were enrolled in the study. Patients were randomly assigned into 2 groups: control group (group C) and treated group (group T). Group C was treated with traditional OLV mode,while group T was given AOI of 5?L/min oxygen on the non-ventilated lung immediately at the beginning of OLV. Arterial blood gas was analyzed before and after OLV. A bronchoalveolar lavage(BAL) was performed after OLV on the non-ventilated lung. Proinflammatory cytokine, oxidative stress markers(TNF-α, NF-κB,sICAM-1,IL-6,IL-10,SOD,MDA) and SP-A, B, C were analyzed in serum and BALF as the primary endpoint.The clinical outcome determined by PPCs was assessed as the secondary endpoint.

Results

Patients with AOI had better oxygenation in the recovery period, oxygenation index(OI) (394[367–426] and 478[440–497]mmHg, respectively) of group T at T2 and T3 were significantly higher than those (332[206–434] and 437[331–512]mmHg, respectively) of group C. OLV resulted in an increase in the measured inflammatory markers in both groups, however, the increase of inflammatory markers upon OLV in the group C was significantly higher than those of group T. OLV resulted in an increase in the measured SP-A, B, C in serum of both groups. However, the levels of SP-A, B, C of group T were lower than those of group C in serum after OLV, and the results in BALF were the opposite. The BALF levels of SOD(23.88[14.70–33.93]U/ml) of group T were higher than those(15.99[10.33–24.16] U/ml) of group C, while the levels of MDA in both serum and BALF of group T(8.60[4.14–9.85] and 1.88[1.33–3.08]nmol/ml, respectively) were all lower than those of group C (11.10[6.57–13.75] and 1.280[1.01–1.83]nmol/ml) after OLV. There was no statistical difference between the two groups in terms of postoperative hospital stay and the incidence of PPCs.

Conclusion

AOI on non-ventilated lung during OLV can improve the oxygenation function after OLV, relieve the inflammatory and oxidative stress response in the systemic and non-ventilated lung after OLV associated with esophagectomy.

Trial registration

ChiCTR-IOR-17011037. Registered on 31 March 2017.
  相似文献   
60.
The rate of electron transfer from NADH to ferricyanide associatedwith corn root plasma membrane vesicles was not significantlyaffected by the presence of Ca2+, Cd2+, Zn2+, or Co2+. However,unlike Ca2+, other tested divalent cations induced an electrontransfer-dependent increase in light scattering by the vesicles.The efficacy in inducing the light scattering increase followedthe order of Cd2+>Zn2+>Co2+. The extent of the light scatteringchange increased as the concentration of added Cd2+ increased.Using phase contrast microscopy, the increase in light scatteringwas related to an expansion of the vesicles. Accompanying thevolume increase, a decrease of Cd2+ concentration in the externalspace was observed by the use of Arsenazo III, a metallochromophorespecific for divalent cations. Under a specified electron transfercondition, a similar percentage of decrease over a wide rangeof initial Cd2+ concentration was detected. The presence ofA23187 [GenBank] decreased the rate and extent of light scattering increaseand its associated Cd2+ concentration change. However, A23187 [GenBank] had no effect on scattering changes already established by theelectron transfer and Cd2+. These results suggest that the NADHlinked electron transfer reaction may induce a Cd2+ uptake bythe vesicles of corn root plasma membrane with inside-out orientation. (Received September 25, 1995; Accepted December 19, 1995)  相似文献   
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