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161.
生态系统服务功能与景观格局耦合协调度研究——以武陵山区退耕还林工程为例 总被引:1,自引:0,他引:1
生态系统服务功能与景观格局演变关系极为密切,研究生态系统服务功能与景观格局的耦合协调度对于区域发展具有重要意义。以武陵山区退耕还林工程为例,参照国家标准和行业标准,采用分布式测算方法、景观格局指数分析和耦合协调度模型等方法,旨在揭示武陵山区退耕还林工程生态系统服务功能与景观格局二者耦合协调关系。结果表明:(1)2005—2017年间武陵山区退耕还林工程各项生态服务功能物质量均以15倍左右速度增长,生态系统服务空间分布格局最佳区域由西部地区逐渐向东南扩大;(2)武陵山区景观演变存在时空差异,1995—2005年景观格局变化更为明显,变化区域集中在中西部地区,2005—2015年与之相比,景观格局变化空间上更为分散;(3)武陵山区退耕还林工程生态系统服务与景观格局演变存在较高水平的耦合以及高水平的协调性。研究结果可为武陵山区土地利用规划及退耕还林工程进一步实施提供科学依据。 相似文献
162.
基于生态系统服务和生态系统健康的生态风险评价——以长株潭城市群为例 总被引:1,自引:0,他引:1
基于生态系统服务和生态系统健康的生态风险评估框架为城市群生态风险管理和国土生态修复提供新的视角。以生态风险评估框架为基础,综合运用生态系统服务、生态系统健康评估模型以及相关分析法对长株潭城市群展开生态风险评价,并对风险程度进行分类。结果表明:(1)城市群的城市化水平提升,区域生态风险也随之增加。生态系统服务价值、生态系统组织、生态系统活力、生态系统弹性等生态指数呈现下降趋势。(2)人工表面比率和生态指数之间的Pearson相关系数表明,人工表面比率与生态指数之间存在负相关关系,人工表面比率是生态风险提升的关键因素。(3)城市群人工表面比率要控制在36%以下,以进行生态风险管理和国土生态修复。总的来说,评价框架可以作为区域生态风险的评价终点。 相似文献
163.
Li Bai Wang Lu Shan Tang Huixin Tang Manman Xu Chen Liang Sujun Zheng Shuang Liu Ming Kong Zhongping Duan Yu Chen 《Cell death & disease》2022,13(9)
We previously documented that M2-like macrophages exert a hepatoprotective effect in acute-on-chronic liver failure (ACLF) by inhibiting necroptosis signalling. Nevertheless, the molecular mechanism behind this hepatoprotection still needs to be further dissected. Galectin-3 (GAL3) has been reported to be critically involved in the pathogenesis of multiple liver diseases, whereas the potential role of GAL3 in ACLF remains to be explored. Herein, we hypothesised that GAL3 plays a pivotal role in the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting necroptosis. To test this hypothesis, we first assessed the expression of GAL3 in control and fibrotic mice with or without acute insult. Second, loss- and gain-of-function experiments of GAL3 were performed. Third, the correlation between GAL3 and M2-like macrophage activation was analysed, and the potential role of GAL3 in M2-like macrophage-conferred hepatoprotection was confirmed. Finally, the molecular mechanism underlying GAL3-mediated hepatoprotection was dissected. GAL3 was found to be obviously upregulated in fibrotic mice with or without acute insult but not in acutely injured mice. Depletion of GAL3 aggravated hepatic damage in fibrotic mice upon insult. Conversely, adoptive transfer of GAL3 provided normal mice enhanced resistance against acute insult. The expression of GAL3 is closely correlated with M2-like macrophage activation. Through adoptive transfer and depletion experiments, M2-like macrophages were verified to act as a major source of GAL3. Importantly, GAL3 was confirmed to hold a pivotal place in the hepatoprotection conferred by M2-like macrophages through loss- and gain-of-function experiments. Unexpectedly, the depletion and adoptive transfer of GAL3 resulted in significant differences in the expression levels of pyroptosis but not necroptosis signalling molecules. Taken together, GAL3 plays a pivotal role in the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting pyroptosis but not necroptosis signalling. Our findings provide novel insights into the pathogenesis and therapy of ACLF.Subject terms: Inflammasome, Necroptosis 相似文献
164.
Farhan Ahmad Gui-Ying Yang Shi-You Liang Qi-Huan Zhou Hassan Ahmed Gaal Jian-Chu Mo 《Insect Science》2021,28(6):1512-1529
Fungus-growing termites are among the most successful herbivorous animals and improve crop productivity and soil fertility. A range of symbiotic organisms can be found inside their nests. However, interactions of termites with these symbionts are poorly understood. This review provides detailed information on the role of multipartite symbioses (between termitophiles, termites, fungi, and bacteria) in fungus-growing termites for lignocellulose degradation. The specific functions of each component in the symbiotic system are also discussed. Based on previous studies, we argue that the enzymatic contribution from the host, fungus, and bacteria greatly facilitates the decomposition of complex polysaccharide plant materials. The host–termitophile interaction protects the termite nest from natural enemies and maintains the stability of the microenvironment inside the colony. 相似文献
165.
Chang Gong Ziliang Cheng Yaping Yang Jun Shen Yingying Zhu Li Ling Wanyi Lin Zhigang Yu Zhihua Li Weige Tan Chushan Zheng Wenbo Zheng Jiajie Zhong Xiang Zhang Yunjie Zeng Qiang Liu R.Stephanie Huang Andrzej L.Komorowski Eddy S.Yang Fran?ois Bertucci Francesco Ricci Armando Orlandi Gianluca Franceschini Kazuaki Takabe Suzanne Klimberg Naohiro Ishii Angela Toss Mona P.Tan Mathew A Cherian Erwei Song 《中国科学:生命科学英文版》2022,65(11):2205-2217
Patients with hormone receptor(HR)-positive tumors breast cancer usually experience a relatively low pathological complete response(p CR) to neoadjuvant chemotherapy(NAC). Here, we derived a 10-micro RNA risk score(10-mi RNA RS)-based model with better performance in the prediction of p CR and validated its relation with the disease-free survival(DFS) in 755 HRpositive breast cancer patients(273, 265, and 217 in the training, internal, and external validation sets, respectively). This model,pres... 相似文献
166.
在28℃下,采用群体累积培养法,探讨了不同浓度的蛋白核小球藻(Chlorella pyrenodeosa)、水华鱼腥藻(Anabaena flas-aquae)和沙角衣藻(Chlamyclomoras sajao),以及在等生物量条件下,以上3种藻类两两配比饵料(3:1、1:1和1:3)对萼花臂尾轮虫(Brachionus calyciflorus)的培养效果。结果表明,不同浓度的蛋白核小球藻、水华鱼腥藻和沙角衣藻对萼花臂尾轮虫增殖效果的影响分别表现为差异极显著(P〈0.01)、显著(P〈0.05)和不显著(P〉0.05);蛋白核小球藻与水华鱼腥藻组成的混合饵料对萼花臂尾轮虫的增殖效果均优于其中的单一种类(P〈0.05);沙角衣藻无论是单独投喂,还是与其它藻类混合投喂,轮虫的培养效果均不理想。因此,该种类不宜用作轮虫饵料开发。该研究还表明,蛋白核小球藻是培养萼花臂尾轮虫的最适单一种类,它与水华鱼腥藻组成的混合饵料培养萼花臂尾轮虫效果更好。 相似文献
167.
浙江黑麂栖息地评价及保护对策 总被引:1,自引:0,他引:1
运用地理信息系统技术,在分析黑麂栖息地的地形、植被、水系和人为干扰等地理特征的基础上,系统研究九龙山和古田山自然保护区黑麂栖息地分布、栖息地质量与空间格局。结果表明,在九龙山自然保护区有黑麂潜在栖息地3172.6hm^2,由于人类活动的影响导致栖息地丧失501.5hm^2,目前尚存的黑麂适宜栖息地2671.1hm^2。它们主要分布于上寮坑、九龙山、内北坪、外九龙和大岩前附近区域。古田山自然保护区有黑麂潜在栖息地4635.75hm^2,在人类活动影响下丧失栖息地1118.11hm^2,目前尚存的黑麂适宜栖息地3517.64hm^2。它们主要分布于青尖、古田山、巧观尖、催顶尖附近区域。目前九龙山和古田山自然保护区内的黑麂栖息地基本上处于多斑块破碎化状态。为了使黑麂能得到更好的保护,对这两个研究区域黑麂栖息地的恢复和重建工作亟待加强。 相似文献
168.
Chengcheng Liang Xiong Xiong Rongwei Cui Yuanxiao Hong Xin Liu Guoru Zhao Lizi Ye Shuxin Qu 《仿生工程学报(英文版)》2021,18(4):927-943
The aim of this study was to reconstruct surface porous structure with hundreds of micrometers and then bio-mineralize Sr-doped Calcium Phosphate(Sr-doped CaP)o... 相似文献
169.
Fangjiao Lv Yang Xu Dean W. Gabriel Xue Wang Ning Zhang Wenxing Liang 《Molecular & cellular proteomics : MCP》2022,21(5):100231
Fusarium oxysporum is one of the most abundant and diverse fungal species found in soils and includes nonpathogenic, endophytic, and pathogenic strains affecting a broad range of plant and animal hosts. Conidiation is the major mode of reproduction in many filamentous fungi, but the regulation of this process is largely unknown. Lysine acetylation (Kac) is an evolutionarily conserved and widespread posttranslational modification implicated in regulation of multiple metabolic processes. A total of 62 upregulated and 49 downregulated Kac proteins were identified in sporulating mycelia versus nonsporulating mycelia of F. oxysporum. Diverse cellular proteins, including glycolytic enzymes, ribosomal proteins, and endoplasmic reticulum–resident molecular chaperones, were differentially acetylated in the sporulation process. Altered Kac levels of three endoplasmic reticulum–resident molecular chaperones, PDIK70, HSP70K604, and HSP40K32 were identified that with important roles in F. oxysporum conidiation. Specifically, K70 acetylation (K70ac) was found to be crucial for maintaining stability and activity of protein disulphide isomerase and the K604ac of HSP70 and K32ac of HSP40 suppressed the detoxification ability of these heat shock proteins, resulting in higher levels of protein aggregation. During conidial formation, an increased level of PDIK70ac and decreased levels of HSP70K604ac and HSP40K32ac contributed to the proper processing of unfolded proteins and eliminated protein aggregation, which is beneficial for dramatic cell biological remodeling during conidiation in F. oxysporum. 相似文献
170.
Shixing Yang Yumin He Ju Zhang Dianqi Zhang Yan Wang Xiang Lu Xiaochun Wang Quan Shen Likai Ji Hongyan Lu Wen Zhang 《中国病毒学》2022,37(1):82-93
Diarrhea is the third leading cause of death in developing countries in children under the age of five. About half a million children die of diarrhea every year, most of which in developing countries. Viruses are the main pathogen of diarrhea. In China, the fecal virome of children with diarrhea has been rarely studied. Using an unbiased viral metagenomics approach, we analyzed the fecal virome in children with diarrhea. Many DNA or RNA viruses associated with diarrhea identified in those fecal samples were mainly from six families of Adenoviridae, Astroviridae, Caliciviridae, Parvoviridae, Picornaviridae, and Reoviridae. Among them, the family of Caliciviridae accounts for the largest proportion of 78.42%, following with Adenoviridae (8.94%) and Picornaviridae (8.36%). In addition to those diarrhea-related viruses that have already been confirmed to cause human diarrhea, the viruses not associated with diarrhea were also identified including anellovirus and picobirnavirus. This study increased our understanding of diarrheic children fecal virome and provided valuable information for the prevention and treatment of viral diarrhea in this area. 相似文献