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91.
韩宝龙  欧阳志云 《生态学报》2021,41(22):8697-8708
开展生态系统服务评估已经成为国土空间功能管治、城市治理、生态产品价值实现等工作中的先行基础动作。生态系统服务的类型和模型方法多,数据需求复杂,传统基于多学科软件开展生态系统服务评估的工作模式知识和技术门槛较高、效率低。当前专业的生态系统服务评估软件多为美国从业人员开发,对我国的数据构成和本地化参数适应性有限。介绍了我国自主开发的生态系统分析软件(城市生态智慧管理系统,IUEMS)的主要功能和应用情况,并将其的生态系统服务评估功能与InVEST、ARIES等国外主流软件在操作逻辑、评估模型、数据取得、空间精度、界面交互五个方面进行了对比。  相似文献   
92.
Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.  相似文献   
93.
In many parts of the world, plantations make up a considerable proportion of the total forest area. In such regions, the identification of high biodiversity value stands and of management practices to enhance biodiversity is essential if the goals of Sustainable Forest Management are to be achieved. Since complete biodiversity assessments are rarely possible, efforts have been increasingly focussed on the use of indicators. Of particular interest are indicators applicable to individual stands that require no specialist taxonomic or technical knowledge to assess. Candidate biodiversity indicators had been identified in a previous study using data from Irish Sitka spruce (Picea sitchensis) and ash (Fraxinus excelsior) plantations but had yet to be tested on independent data. In the present study, the provisional indicators for vascular plant, bryophyte, spider and bird diversity were tested on data from Irish Scots pine (Pinus sylvestris), oak (Quercus petraea/Quercus robur), Sitka spruce and lodgepole pine (Pinus contorta) plantations. Conifer canopy cover was confirmed as an important biodiversity indicator, due to its influence on below-canopy microclimatic and structural conditions. Bryophyte species richness was higher in relatively high canopy cover plantations on poorly drained soils, while bird species richness was higher in more open plantations with high shrub cover. Coarse woody debris was an important substrate for forest-associated bryophytes, with higher species richness at higher volumes of deadwood. Both proximity to old woodland and stand age were confirmed as positive indicators for forest-associated vascular plants. This is related to dispersal limitation in these species, with nearby woodlands acting as important seed sources and colonisation increasing with time. Stand age was also confirmed as a positive indicator for forest-associated spiders and is related to the development of suitable habitat as the plantation matures. All of the confirmed indicators can be assessed without need for specialist knowledge, are ecologically meaningful and applicable to a range of forests managed under a clearfelling system. They can be used to assess the potential value of stands for the taxonomic groups to which they apply, as well as giving insights into management practices to enhance diversity in these groups.  相似文献   
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Idiopathic pulmonary fibrosis (IPF) is a chronic, fibrosing interstitial lung disease that primarily affects older adults. Median survival after diagnosis is 2–3 years. The clinical course of IPF may include periods of acute deterioration in respiratory function, which are termed acute exacerbations of IPF (AEx-IPF) when a cause cannot be identified. AEx-IPF may represent a sudden acceleration of the underlying disease process of IPF, or a biologically distinct pathological process that is clinically undiagnosed. An AEx-IPF can occur at any time during the course of IPF and may be the presenting manifestation. The incidence of AEx-IPF is hard to establish due to variation in the methodology used to assess AEx-IPF in different studies, but AEx-IPF are believed to occur in between 5 and 10% of patients with IPF every year. Risk factors for AEx-IPF are unclear, but there is evidence that poorer lung function increases the risk of an AEx-IPF and reduces the chances of a patient surviving an AEx-IPF. The presence of comorbidities such as gastroesophageal reflux disease (GERD) and pulmonary hypertension may also increase the risk of an AEx-IPF. AEx-IPF are associated with high morbidity and mortality. Patients who experience an AEx-IPF show a worsened prognosis and AEx-IPF are believed to reflect disease progression in IPF. Current treatments for AEx-IPF have only limited data to support their effectiveness. The latest international treatment guidelines state that supportive care remains the mainstay of treatment for AEx-IPF, but also give a weak recommendation for the treatment of the majority of patients with AEx-IPF with corticosteroids. There is emerging evidence from clinical trials of investigational therapies that chronic treatment of IPF may reduce the incidence of AEx-IPF. Additional clinical trials investigating this are underway.  相似文献   
97.
Healthier eating is a global challenge for chronic disease control. Food and Health Research in Europe (FAHRE) surveyed research structures and programmes in 32 countries, and reviewed research needs and gaps across nine themes. Food processing and safety research, nutrition and molecular research, and disease-based clinical research are strong; but research is weak on determinants of disease and healthier eating through policies and changing behaviours. Biomedical and commercial research for patents contrast with social research for the public interest. More funding and capacity support should go to social research in the food and health sector.  相似文献   
98.
肠道微生物对肠道屏障功能完整性的维护机制研究概况   总被引:2,自引:1,他引:1  
肠道微生物群是一个稳定且复杂的生态系统,可以通过形成菌膜屏障或促进肠道上皮细胞增殖分化等方式形成保护屏障,并在肠道病原菌感染和威胁期间维持和促进免疫稳态中起积极作用。本文重点叙述宿主-肠道微生物相互作用过程中抗病原菌感染的方式,以及肠道微生物参与合成抗菌化合物抵御肠道病原菌入侵和威胁的机制,为调控肠道微生物解决临床胃肠道疾病及其相关症状提供理论参考依据。  相似文献   
99.

Background

Campylobacter jejuni is an important food-borne and zoonotic pathogen with a worldwide distribution. Humans and chickens are hosts of this pathogen. At present, there is no ideal vaccine for controlling human campylobacteriosis or the carriage of C. jejuni by chickens. Bacterial in vivo-induced antigens are useful as potential vaccine candidates and biomarkers of virulence.

Methods

In this study, we developed a novel systematic immunoproteomics approach to identify in vivo-induced antigens among the total cell proteins of C. jejuni using pre-adsorbed sera from patients infected with C. jejuni.

Results

Overall, 14 immunoreactive spots were probed on a PVDF membrane using pre-adsorbed human sera against C. jejuni. Then, we excised these protein spots from a duplicate gel and identified using MALDI–TOF MS. In total, 14 in vivo-induced antigens were identified using PMF and BLAST analysis. The identified proteins include CadF (CadF-1 and CadF-2), CheW, TufB, DnaK, MetK, LpxB, HslU, DmsA, PorA, ProS, CJBH_0976, CSU_0396 and hypothetical protein cje135_05017. Real-time RT-PCR was performed on 9 genes to compare their expression levels in vivo and in vitro. The data showed that 8 of the 9 analyzed genes were significantly upregulated in vivo relative to in vitro.

Conclusion

We successfully developed a novel immunoproteomics method for identifying in vivo-induced Campylobacter jejuni antigens by using pre-adsorbed sera from infected patients.

General significance

This new analysis method may prove to be useful for identifying in vivo-induced antigens within any host infected by bacteria and will contribute to the development of new subunit vaccines.  相似文献   
100.

The effects of puddling and water regimes on hydraulic conductivity (cm/day) of soil and on bulk density (mg/m 3 ) during rice culture, soil physical characteristics of the experimental field population densities of plant-parasitic nematodes have been studied. Puddling reduced the bulk density of soil and decreased the hydraulic conductivity in the upper layers but not in the deeper layers of soil aeration was reduced due to high moisture levels retained in the puddled soil. Population density of M. triticoryzae declined in puddled soil. The invasion of the roots by the second-generation infective juveniles was reduced. The population density of the root-knot nematodes was higher in the non-puddled soil especially in unsubmerged condition compared to puddled and submerged soil. However, if the seedlings were already infected before transplanting and submergence, the nematode could survive well and reproduce within the aerenchyma of the root.  相似文献   
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