Administrator of global biodiversity: The secretariat of the convention on biological diversity

The paper presents a case study analysing the effects of the Secretariat of the Convention on Biological Diversity as an intergovernmental organisation. Within the study, the effects of organisations are measured by their outcome, i.e. the influence on the behaviour of other actors such as national governments. Three forms of outcomes are being distinguished, namely knowledge brokerage and diffusion, capacity building, and negotiation facilitation. In addition, the paper tries to explain the observed effects on the basis of internal and external variables. The CBD Secretariat has been established in 1992 and is now located in Montreal with about 70 employees. As most other secretariats of international conventions, it is the main organiser and facilitator of the convention process. The empirical material shows that the Secretariat has a measurable influence on the intergovernmental cooperative process which can be attributed to the effective internal management processes and the qualities of its leaders. Lacking capacity building functions and highly selective effects with regard to the provision of knowledge are explained by the limited formal autonomy and the structure of the global biodiversity problem.     

Antimicrobial resistance in humans,livestock and the wider environment

Antimicrobial resistance (AMR) in humans is inter-linked with AMR in other populations, especially farm animals, and in the wider environment. The relatively few bacterial species that cause disease in humans, and are the targets of antibiotic treatment, constitute a tiny subset of the overall diversity of bacteria that includes the gut microbiota and vast numbers in the soil. However, resistance can pass between these different populations; and homologous resistance genes have been found in pathogens, normal flora and soil bacteria. Farm animals are an important component of this complex system: they are exposed to enormous quantities of antibiotics (despite attempts at reduction) and act as another reservoir of resistance genes. Whole genome sequencing is revealing and beginning to quantify the two-way traffic of AMR bacteria between the farm and the clinic. Surveillance of bacterial disease, drug usage and resistance in livestock is still relatively poor, though improving, but achieving better antimicrobial stewardship on the farm is challenging: antibiotics are an integral part of industrial agriculture and there are very few alternatives. Human production and use of antibiotics either on the farm or in the clinic is but a recent addition to the natural and ancient process of antibiotic production and resistance evolution that occurs on a global scale in the soil. Viewed in this way, AMR is somewhat analogous to climate change, and that suggests that an intergovernmental panel, akin to the Intergovernmental Panel on Climate Change, could be an appropriate vehicle to actively address the problem.     

Evaluation of the effect of accounting method,IPCC v. LCA,on grass-based and confinement dairy systems’ greenhouse gas emissions

Life cycle assessment (LCA) and the Intergovernmental Panel on Climate Change (IPCC) guideline methodology, which are the principal greenhouse gas (GHG) quantification methods, were evaluated in this study using a dairy farm GHG model. The model was applied to estimate GHG emissions from two contrasting dairy systems: a seasonal calving pasture-based dairy farm and a total confinement dairy system. Data used to quantify emissions from these systems originated from a research study carried out over a 1-year period in Ireland. The genetic merit of cows modelled was similar for both systems. Total mixed ration was fed in the Confinement system, whereas grazed grass was mainly fed in the grass-based system. GHG emissions from these systems were quantified per unit of product and area. The results of both methods showed that the dairy system that emitted the lowest GHG emissions per unit area did not necessarily emit the lowest GHG emissions possible for a given level of product. Consequently, a recommendation from this study is that GHG emissions be evaluated per unit of product given the growing affluent human population and increasing demand for dairy products. The IPCC and LCA methods ranked dairy systems’ GHG emissions differently. For instance, the IPCC method quantified that the Confinement system reduced GHG emissions per unit of product by 8% compared with the grass-based system, but the LCA approach calculated that the Confinement system increased emissions by 16% when off-farm emissions associated with primary dairy production were included. Thus, GHG emissions should be quantified using approaches that quantify the total GHG emissions associated with the production system, so as to determine whether the dairy system was causing emissions displacement. The IPCC and LCA methods were also used in this study to simulate, through a dairy farm GHG model, what effect management changes within both production systems have on GHG emissions. The findings suggest that single changes have a small mitigating effect on GHG emissions (<5%), except for strategies used to control emissions from manure storage in the Confinement system (14% to 24%). However, when several management strategies were combined, GHG emissions per unit of product could be reduced significantly (15% to 30%). The LCA method was identified as the preferred approach to assess the effect of management changes on GHG emissions, but the analysis indicated that further standardisation of the approach is needed given the sensitivity of the approach to allocation decisions regarding milk and meat.     

Temperature effects on photosynthesis in gametophytic and sporophytic stages of the freshwater red alga Sirodotia delicatula (Rhodophyta,Batrachospermales) under a global warming perspective

The increase in Earth's global mean temperature due to human influence has become a major concern, with ecological consequences already being reported around the world. In tropical streams, benthic red algae belonging to the order Batrachospermales contribute to a large fraction of the community energy input and play an important role in sustaining autotrophic food webs. The Batrachospermales also have a unique life history, with heteromorphic life stages (gametophytes and sporophytes) occurring seasonally and with distinct ecological roles. Through “in vivo” chlorophyll fluorescence and dissolved oxygen evolution techniques, we evaluated the effects of projected temperature increases of two future scenarios (RCP 4.5 and RCP 8.5) on the photosynthetic response of Sirodotia delicatula gametophytes and sporophytes. In general, both chlorophyll fluorescence and dissolved oxygen showed that the RCP 8.5 scenario could severely jeopardize the photosynthetic performance of the sporophytes during the summer while also providing a stressful physiological situation to the gametophytes. Due to the crucial role of sporophytes in the development of this species, results indicate that this predicted scenario could affect this species. Given the position of these organisms at the base of the food web in tropical lotic environments, especially in shaded low‐order streams, such impact could generate unforeseen cascade effects on higher trophic levels.     

Temperature,but not pH,compromises sea urchin fertilization and early development under near-future climate change scenarios

Global warming is causing ocean warming and acidification. The distribution of Heliocidaris erythrogramma coincides with the eastern Australia climate change hot spot, where disproportionate warming makes marine biota particularly vulnerable to climate change. In keeping with near-future climate change scenarios, we determined the interactive effects of warming and acidification on fertilization and development of this echinoid. Experimental treatments (20–26°C, pH 7.6–8.2) were tested in all combinations for the ‘business-as-usual’ scenario, with 20°C/pH 8.2 being ambient. Percentage of fertilization was high (>89%) across all treatments. There was no difference in percentage of normal development in any pH treatment. In elevated temperature conditions, +4°C reduced cleavage by 40 per cent and +6°C by a further 20 per cent. Normal gastrulation fell below 4 per cent at +6°C. At 26°C, development was impaired. As the first study of interactive effects of temperature and pH on sea urchin development, we confirm the thermotolerance and pH resilience of fertilization and embryogenesis within predicted climate change scenarios, with negative effects at upper limits of ocean warming. Our findings place single stressor studies in context and emphasize the need for experiments that address ocean warming and acidification concurrently. Although ocean acidification research has focused on impaired calcification, embryos may not reach the skeletogenic stage in a warm ocean.     

我国县级公立医院改革模式的比较

县级公立医院改革是我国医药卫生体制改革的“重心”。绩效型行政化和治理型市场化是破除管制型市场化的两大改革模式。从基本观点和制度安排两个角度对绩效型行政化和治理型市场化两大改革模式进行比较,并提出推进治理型市场化改革模式的主要思路。     

Effects of selenium on chemical carcinogenesis

Chemical carcinogenesis can be characterized by a sequence of events leading to the development of tumors. Selenium (Se) inhibition of colon, liver, and lung carcinogens is demonstrated. Using the male Sprague Dawley rat model Se inhibited the colon tumor incidence in 1,2-dimethylhydrazine (DMH) treated rats and reduced the total number of colon tumors in methylazoxymethanol (MAM) treated rats. Selenium inhibited 2-acetylaminofluorene (AAF) and 3′-methyl-4-dimethylaminoazobenzene (3′-MeDAB) hepatocarcinogenesis. The hepatic tumor incidence induced by 3′-MeDAB was reduced by both inorganic Se (Na₂SeO₃) and by organic Se (Se-yeast) supplements. In vitro systems have been studied in an effort to decipher the inhibitory properties of Se on the multistage origin of tumors induced by chemical carcinogens. Current studies suggest that the protective effect of Se against AAF hepatocarcinogenesis may be correlated with a change in AAF metabolism. The mutagenicity of AAF and AAF metabolites inSalmonella typhimurium TA1538 is decreased by Se. Additionally, Se reduced N-t-OH−AAF induction of sister chromatid exchange (SCE) frequencies in whole blood cultures, and also reduced aryl hydrocarbon hydroxylase activity using benzo(a) pyrene as substrate. The comparative effects of antioxidants on DMH induction of colon tumors are presented in detail. Supplements of 4 ppm Se to the drinking water, 1.2% ascorbic acid (V _c ) to the diet or 0.5% butylated hydroxytoluene (BHT) to the diet of DMH-treated rats reduced the colon tumor incidence of DMH controls from 64 to 31% (Se), 38% (V _c ), and 43% (BHT). The colon tumor incidence in DMH-treated rats receiving a combination of Se+V _c increased to 83%, while the combination of Se+BHT decreased the colon tumor incidence to 55%. The growth and survival of rats provided long-term supplements of 4 ppm Se in the drinking water are compared with untreated controls.     

骨痹消对兔骨性膝关节炎软骨细胞p53、Bcl-2表达的影响

目的探讨骨痹消对兔实验性膝关节骨性关节炎(KOA)的治疗作用。方法参照文献[1]介绍的伸膝制动方法复制KOA动物模型,并随机分为正常组(A组)、模型组(B组)、骨痹消组(C组),治疗6周、10周后采用免疫组化技术测各组软骨细胞p53、Bcl-2表达。结果与正常组比较,模型组Bcl-2、p53表达增高,且其表达水平随着病程(6w、10w)呈正相关,骨痹消组用药6w及10w时Bcl-2的表达随时间的延长呈逐渐增强的趋势,较模型组相比呈显著性差异(P0.01),同时p53的阳性表达明显下降,与模型组相比均呈显著性意义(P0.01)。结论抑凋亡(APO)基因Bcl-2和促APO基因p53共同参与了软骨细胞APO的调节,骨痹消可通过上调Bcl-2、下调p53表达,以保护软骨细胞,防止发生APO。     

稻株上拮抗细菌的定殖及其对土著细菌的影响

在温室条件下,通过分批播种、接种纹枯病菌Rhizoctonia solani,以及在水稻分孽盛期喷雾拮抗细菌Pseudomonas fluorescens Pf7-14 (天然的抗萘啶酮酸菌株) 和B5423-R(Bacillus subtilis B5423的利福平抗性突变体)的菌悬浮液,并通过定期取样,平板系列稀释法回收,测定了菌株Pf7-14、B5423-R和土著细菌群体在水稻健株和纹枯病株上的种群数量,所获结果如下:①当相同的浓度(约2.0×108cfu/ml)的菌悬浮液喷雾到叶片时,菌株Pf7-14定殖的时间比菌株B5423-R长,且在相同的时间内,菌株Pf7-14的平均群体数量高于菌株B5423-R;②在健康的水稻茎部,菌株Pf7-14的两个高、低不同浓度处理的平均群体数量均表现出随时间降低的趋势;相比,较低浓度(4.0×107cfu/ml)的B5423-R在茎部的平均群体数量随着时间的下降,而较高浓度(2.0×108cfu/ml)的B5423-R的平均群体数量在水稻乳熟至黄熟期保持稳定或略有增长;③当病斑面积占取样茎面积的比率为20%～35%时,在应用1和14d后菌株Pf7-14在健茎的平均群体数量分别是病茎的6倍多和2倍多,差异均达到显著性的水平(P=0.05),而菌株B5423-R 在应用1d后病茎的数量比在健茎显著性地低大约1倍,但在7～14d后,病茎的数量比在健茎显著性地高5～6倍,群体在病茎表现出相对的增长;④土著细菌群体在病斑茎部是健茎的6～7倍.这些结果表明两类拮抗细菌有着明显不同的定殖习性,在病斑上B5423比Pf7-14具有更强的竞争能力,是一类更好的生防制剂;同时表明引入的拮抗细菌同土著细菌群体在营养和空间上竞争激烈,且土著细菌群体更具有竞争优势.