Microscopic Methods for Identification of Sulfate-Reducing Bacteria from Various Habitats

This paper is devoted to microscopic methods for the identification of sulfate-reducing bacteria (SRB). In this context, it describes various habitats, morphology and techniques used for the detection and identification of this very heterogeneous group of anaerobic microorganisms. SRB are present in almost every habitat on Earth, including freshwater and marine water, soils, sediments or animals. In the oil, water and gas industries, they can cause considerable economic losses due to their hydrogen sulfide production; in periodontal lesions and the colon of humans, they can cause health complications. Although the role of these bacteria in inflammatory bowel diseases is not entirely known yet, their presence is increased in patients and produced hydrogen sulfide has a cytotoxic effect. For these reasons, methods for the detection of these microorganisms were described. Apart from selected molecular techniques, including metagenomics, fluorescence microscopy was one of the applied methods. Especially fluorescence in situ hybridization (FISH) in various modifications was described. This method enables visual identification of SRB, determining their abundance and spatial distribution in environmental biofilms and gut samples.     

Relative contributions of nearshore and wetland habitats to coastal food webs in the Great Lakes

Hydrologic linkages among coastal wetland and nearshore areas allow coastal fish to move among the habitats, which has led to a variety of habitat use patterns. We determined nutritional support of coastal fishes from 12 wetland-nearshore habitat pairs using stable isotope analyses, which revealed differences among species and systems in multi-habitat use. Substantial (proportions?>?0.30) nutrition often came from the habitat other than that in which fish were captured. Nearshore subsidies to coastal wetlands indicate wetlands are not exclusively exporters of energy and materials; rather, there is reciprocity in the mutual energetic support of nearshore and wetland food webs. Coastal wetland hydrogeomorphology influenced the amount of multi-habitat use by coastal fishes. Fishes from systems with relatively open interfaces between wetland and nearshore habitats exhibited less nutritional reliance on the habitat in which they were captured, and higher use of resources from the adjacent habitat. Comparisons of stable isotope analyses of nutrition with otolith analyses of occupancy indicated nutritional sources often corresponded with habitat occupancy; however, disparities among place of capture, otolith analyses, and nutritional analyses indicated differences in the types of support those analyses inform. Disparities between occupancy information and nutritional information can stem from movements for support functions other than foraging. Together, occupancy information from otolith microchemistry and nutritional information from stable isotope analyses provide complementary measures of the use of multiple habitats by mobile consumers. This work underscores the importance of protecting or restoring a diversity of coastal habitats and the hydrologic linkages among them.     

Assessing landscape perception of urban rocky habitats

The urban landscape structure and its changing characteristics have produced various effects on natural and human systems of its own and surroundings [Gilbert OL. The ecology of urban habitats. London: Chapman & Hall; 1991 [1]; Rebele F. Urban ecology and special features of urban ecosystems. Global Ecology and Biogeography Letters 1994;4:173–87 [2]; Rees WE. Urban ecosystems: the human dimension. Urban Ecosystems 1997;1:63–75 [3]; Pickett STA, Cadenasso ML, Grove JM, Nilon CH, Pouyat RV, Zipperer WC, et al. Urban ecological systems: linking terrestrial ecological, physical, and socioeconomic components of metropolitan areas. Annual Review of Ecology and Systematics 2001;32:127–57 [4]; Hope D, Gries C, Zhu WX, Fagan WF, Redman CL, Grimm NB, et al., Socioeconomics drive urban plant diversity. Proceedings of the National Academy of Sciences of the United States of America 2003;100(15):8788–92 [5]; Pickett STA, Cadenasso ML, Grove JM. Resilient cities: meaning, models, and metaphor for integrating the ecological, socio-economic, and planning realms, Landscape and Urban Planning 2004;69(4):369–84 [6]; Luck M, Jianguo Wu J. A gradient analysis of urban landscape pattern: a case study from the Phoenix metropolitan region, Arizona, USA. Landscape Ecology 2002:17(4):327–39 [7]; Angold PG, Sadler JP, Hill MO, Pullin A, Rushton S, Austin K, et al., Biodiversity in urban habitat patches. Science of the Total Environment 2006;360(1–3):196–204 [8]]. By environmental literature conducted recently, it has been evidently comprehended that urban life quality for mankind and others can be improved by serving these systems with green and living elements. This study is to investigate urban rocky habitats that have special natural characteristics and that can be implicated for urban green areas. But these habitats have been considered as nature splits withstanding against the urban pressures by means of the unplanned build-up activities foremost, and road construction, poor quality or neglected remnants. Therefore, this study presents the environmental perception and preferences of urban rocky habitats which are threatening within excessive urbanization and human use of natural areas in the context of the city of Trabzon, Turkey. So, a total of 20 habitats selected from urban and surroundings were surveyed by using a questionnaire and landscape assessment approach. With surveying performed on 204 participants, visual preferences, landscape attributes and proposed management options for urban nature conservation were determined. The χ²${\chi }^2$-test results revealed clearly that the demographic and expertise status of the participants were correlated with the preferences for types of rocky habitat scene and management options. The scenes with natural elements and less human disturbance obtained higher scores on visual preferences than any of the urban rocky scenes lacking these characteristics. Also, in the quantitative phase, factor analysis based on principal component structure revealed the ‘visual and spatial effects’, the ‘usage and arrangement’, the ‘naturalness and ecological value’, and the ‘functionality’ components of the scenes. Consequently, some implications for the effective and efficient planning and development of urban nature conservation by assisting the better understanding of the various patterns of landscape preference, choice and satisfaction in habitats under the present study were suggested.     

Shotgun metagenomics of dust microbiome from flight deck and cabin in civil aviation aircraft

Microbial exposure is related to the health of passengers on commercial aircraft, but no studies characterized the microbial composition at the species level and identified their ecological determinants. We collected vacuum dust from floor and seat surfaces in flight decks and cabins of 18 aircraft, and amplification-free shotgun metagenomics was conducted to characterize the microbial composition. In total, 7437 microbial taxa were identified. The relative abundance for bacteria, eukaryote, viruses, and archaea was 96.9%, 1.8%, 0.3%, and 0.03%, respectively. The top bacterial species mainly derived from outdoor air and human skin included Sphingomonas, Corynebacterium, Micrococcus luteus, Variovorax paradoxus, Paracoccus dentrificans, and Propionibacterium acnes. The abundance of NIAID-defined pathogens was low, accounted for only 0.23% of total microbes. The microbial species and functional composition were structured by the indoor surface type (R² = 0.38, Adonis), followed by the manufacturer of the aircraft (R² = 0.12) and flight duration (R² = 0.07). Indoor surfaces affected species derived from different habitats; the abundance of dry skin and desiccated species was higher on textile surfaces, whereas the abundance of moist and oily skin species was higher on leather surfaces. The growth rates for most microbes were stopped and almost stopped.     

人禽流感裂解疫苗对小鼠的免疫原性观察

目的观察人禽流感裂解疫苗对小鼠的免疫原性。方法将不同血凝素含量(20、30、45μg/ml)的铝佐剂和无佐剂人禽流感裂解疫苗各3批分别经腹腔注射免疫小鼠,0.5 ml/只,每批疫苗又分为1针、2针和3针组,每组10只,每针间隔1周,同时设空白对照组。首针免疫后21 d,分别采血,分离血清,检测血凝抑制抗体效价和中和抗体效价。结果 1针、2针组各3批无佐剂疫苗免疫小鼠的血凝抑制抗体效价和中和抗体效价分别小于1∶40和1∶200;2针、3针组各3批铝佐剂疫苗的血凝抑制抗体效价均大于1∶50,2针组20、30μg/ml血凝素铝佐剂疫苗的中和抗体效价均大于1∶200;2针、3针组20、30与45μg/ml血凝素铝佐剂疫苗的血凝抑制抗体效价和中和抗体效价差异均无统计学意义(P>0.05);且2针、3针组3批铝佐剂疫苗的血凝抑制抗体效价和中和抗体效价均明显高于相应的3批无佐剂疫苗。结论铝佐剂疫苗对小鼠的免疫原性明显优于无佐剂疫苗,且20、30μg/ml血凝素铝佐剂疫苗接种2针可获得理想的免疫效果。     

格物致知：一个永恒的教育理想——黄晓慧博士论文《大学教育知识的微观政治哲学分析》序

格物致知,是2000多年前儒家为人生理想提炼的一句箴言;而知识栖息地,则是2010年英国学者哈珀为大学伟大描绘的一个隐喻。山高水长,时空穿越,不灭的光亮正是格物致知这个永恒的教育理想。也许就是这个点燃智慧的光亮,引领每一个人、所有学校和整个人类,孜孜不倦地投身到格物致知那绵延不绝的追求行动之中。一种理想的格物致知教育生活便一直伴随着我们：人类在创造知识中进步,学校在传播知识中发展,个人在识知探求中升华。     

Impact of the implementation of rest days in live bird markets on the dynamics of H5N1 highly pathogenic avian influenza

Live bird markets (LBMs) act as a network ‘hub’ and potential reservoir of infection for domestic poultry. They may therefore be responsible for sustaining H5N1 highly pathogenic avian influenza (HPAI) virus circulation within the poultry sector, and thus a suitable target for implementing control strategies. We developed a stochastic transmission model to understand how market functioning impacts on the transmission dynamics. We then investigated the potential for rest days—periods during which markets are emptied and disinfected—to modulate the dynamics of H5N1 HPAI within the poultry sector using a stochastic meta-population model. Our results suggest that under plausible parameter scenarios, HPAI H5N1 could be sustained silently within LBMs with the time spent by poultry in markets and the frequency of introduction of new susceptible birds'' dominant factors determining sustained silent spread. Compared with interventions applied in farms (i.e. stamping out, vaccination), our model shows that frequent rest days are an effective means to reduce HPAI transmission. Furthermore, our model predicts that full market closure would be only slightly more effective than rest days to reduce transmission. Strategies applied within markets could thus help to control transmission of the disease.     

Spatial dynamics of bar-headed geese migration in the context of H5N1

Virulent outbreaks of highly pathogenic avian influenza (HPAI) since 2005 have raised the question about the roles of migratory and wild birds in the transmission of HPAI. Despite increased monitoring, the role of wild waterfowl as the primary source of the highly pathogenic H5N1 has not been clearly established. The impact of outbreaks of HPAI among species of wild birds which are already endangered can nevertheless have devastating consequences for the local and non-local ecology where migratory species are established. Understanding the entangled dynamics of migration and the disease dynamics will be key to prevention and control measures for humans, migratory birds and poultry. Here, we present a spatial dynamic model of seasonal migration derived from first principles and linking the local dynamics during migratory stopovers to the larger scale migratory routes. We discuss the effect of repeated epizootic at specific migratory stopovers for bar-headed geese (Anser indicus). We find that repeated deadly outbreaks of H5N1 on stopovers during the autumn migration of bar-headed geese could lead to a larger reduction in the size of the equilibrium bird population compared with that obtained after repeated outbreaks during the spring migration. However, the opposite is true during the first few years of transition to such an equilibrium. The age-maturation process of juvenile birds which are more susceptible to H5N1 reinforces this result.     

人与人传染的有媒体影响因子的禽流感模型

建立人与人之间相互传染的有媒体影响因子的SI-SIR禽流感模型,并研究其动力学性态,得到判断疾病传播与否的阈值R_a和R_0.利用Lyapunov函数、Dulac函数以及LaSalle不变原理等证明了当R_a1且R_01时,无病平衡点E_0~*是全局渐近稳定的;当R_a1且R_01时,边界平衡点E_1~*是全局渐近稳定的;当R_a1时,系统的正平衡点E_2~*是全局渐近稳定的.     

具有饱和治疗率的H7N9型禽流感模型的动力学性态分析

建立具有饱和治疗率的H7N9型禽流感模型,研究媒体报道和饱和治疗对禽流感传播的影响.定义模型的基本再生数,利用V函数、Dulac函数和极限方程理论等对模型进行动力学性态的分析.证明当基本再生数小于等于1时,无病平衡点全局渐近稳定;当基本再生数大于1时,地方病平衡点全局渐近稳定.数值模拟验证了本文的理论结果.