The Drosophila DOCK family protein sponge is involved in differentiation of R7 photoreceptor cells

The Drosophila sponge (spg)/CG31048 gene belongs to the dedicator of cytokinesis (DOCK) family genes that are conserved in a wide variety of species. DOCK family members are known as DOCK1–DOCK11 in mammals. Although DOCK1 and DOCK2 involve neurite elongation and immunocyte differentiation, respectively, the functions of other DOCK family members are not fully understood. Spg is a Drosophila homolog of mammalian DOCK3 and DOCK4. Specific knockdown of spg by the GMR-GAL4 driver in eye imaginal discs induced abnormal eye morphology in adults. To mark the photoreceptor cells in eye imaginal discs, we used a set of enhancer trap strains that express lacZ in various sets of photoreceptor cells. Immunostaining with anti-Spg antibodies and anti-lacZ antibodies revealed that Spg is localized mainly in R7 photoreceptor cells. Knockdown of spg by the GMR-GAL4 driver reduced signals of R7 photoreceptor cells, suggesting involvement of Spg in R7 cell differentiation. Furthermore, immunostaining with anti-dpERK antibodies showed the level of activated ERK signal was reduced extensively by knockdown of spg in eye discs, and both the defects in eye morphology and dpERK signals were rescued by over-expression of the Drosophila raf gene, a component of the ERK signaling pathway. Furthermore, the Duolink in situ Proximity Ligation Assay method detected interaction signals between Spg and Rap1 in and around the plasma membrane of the eye disc cells. Together, these results indicate Spg positively regulates the ERK pathway that is required for R7 photoreceptor cell differentiation and the regulation is mediated by interaction with Rap1 during development of the compound eye.     

Eco-efficiency of urban material metabolism: a case study in Shenzhen, China

The keys of studying urban sustainable development are material metabolism flux and efficiency. Metabolism flux of urban materials can only reflect the metabolism velocity, while its eco-efficiency can determine the metabolism capacity to support socio-economic development. The general model and the measure model of the eco-efficiency were set up, based on the source recycle (decreasing the consumption of crude resources) and the terminal recycle (decreasing the discharge of pollutants) of production and life. These models were employed to study material metabolism flux and efficiency in Shenzhen, China. Results showed that water, energy and waste metabolism fluxes have increased since 1998 with constant socio-economic development, and their eco-efficiencies have also increased rapidly. When GDP rose by 2.7 times, the metabolism fluxes of urban water and electricity rose by 1.5 and 3.0 times, respectively. When the added value of industry rose by 3.7 times, the metabolism fluxes of industrial water, electricity, energy and waste rose by 1.9, 3.5, 2.7 and 2.0 times, respectively. When population rose by 1.5 times, the metabolism fluxes of residential water and electricity rose by 1.8 and 1.7 times, respectively. During the period, the resource efficiency, environmental efficiency and eco-efficiency rose by 1.8, 3.7 and 2.3 times, respectively. Whereas the efficiency of material metabolism has been improved in Shenzhen, the scarcity of material resources has become more and more serious. Therefore, it is necessary to further improve the efficiency of material metabolism. The keys of improving the eco-efficiency of urban material metabolism are the increasing of resource and environmental efficiencies, and the establishing of the recycling chain of re-utilization of waste resources.     

武夷山国家公园及其周边鱼类多样性

武夷山国家公园是中国正式设立的第一批国家公园之一, 其所处的武夷山脉在动物地理区划上是东洋区南亚亚区华南小区、东洋区东亚亚区华东小区的分界线。为查明武夷山国家公园及其周边的鱼类区系和多样性现状, 本研究在梳理历史研究资料的基础上, 对调查区域内的崇阳溪、麻阳溪、九曲溪、北溪和铅山河5条河流进行了实地调查, 从物种多样性和功能多样性两个层面对武夷山国家公园及其周边地区鱼类多样性水平进行了分析。结合历史数据, 武夷山国家公园及其周边地区分布的土著鱼类为113种, 隶属于5目17科61属, 其中以鲤形目鱼类为主, 共82种, 占物种总数的72.6%, 其次为鲈形目, 共16种, 占总数的14.2%。受威胁鱼类3种, 包括2种国家II级野生水生保护动物, 即胭脂鱼(Myxocyprinus asiaticus)和花鳗鲡(Anguilla marmorata)。武夷山国家公园的第一优势种为拟腹吸鳅(Pseudogastromyzon fasciatus), 与其周边地区以点纹银鮈(Squalidus wolterstorffi)为第一优势种不同。多样性分析结果显示武夷山国家公园的鱼类物种丰富度指数、多样性指数和均匀度指数均低于周边区域。通过比较调查区域内5条河流的鱼类多样性, 麻阳溪鱼类多样性显著高于其他河流, 铅山河的多样性显著低于其他河流。位于国家公园内的九曲溪鱼类多样性比周边地区的崇阳溪要低。鱼类功能多样性结果显示, 武夷山国家公园的功能丰富度指数显著低于周边地区, 功能离散度和功能均匀度均高于周边地区; 在河流方面, 北溪的功能丰富度显著高于其他河流, 崇阳溪的功能均匀度较高, 九曲溪的功能离散度显著高于其他河流。综合鱼类多样性分析结果, 武夷山国家公园鱼类多样性低主要是自然生境异质性低和人为活动共同作用形成, 而周边地区的河流受到捕捞、水利设施、水质污染等因素的影响。这些干扰改变了鱼类的群落结构, 使得鱼类多样性降低。因此应该加强对该区域的鱼类多样性保护工作, 未来还应进一步开展针对公园内鱼类多样性的调查工作。     

Landscape effects on birds in urban woodlands: an analysis of 34 Swedish cities

Aim To compare bird abundances in woodlands along gradients from the city centre to the peri‐urban area. To evaluate the importance of the proportion of woodland within the city and in the peri‐urban landscape to forest bird communities breeding in urban woodlands. To test whether fragmentation effects on birds were linked to the type of peri‐urban matrix. Location A total of 34 Swedish cities with > 10,000 inhabitants in south‐central Sweden. The study area covered 105,000 km², in which 84% of the Swedish population of 9.1 million lives. Methods Repeated point count surveys were conducted in 2004 in a total of 474 woodlands. General linear models were used to test for possible differences in abundance along urban to peri‐urban gradients, and to regress bird abundances in local urban woodlands on: (1) total woodland cover in the city, (2) total woodland cover in the peri‐urban landscape, (3) the interaction between woodland cover in the city and in the peri‐urban area, (4) region, and (5) human density. Results More than 12,000 individuals of 100 forest bird species were recorded. Of the 34 most common species detected, 13 bird species had higher abundances in urban than in peri‐urban woodlands, and seven species showed the opposite trend. The bird community of urban woodlands was characterized by species associated with deciduous forests and tree nesters, whereas the bird community of peri‐urban woodlands was characterized by species associated with coniferous woodland and ground nesters. Twelve species were significantly linearly associated with the proportion of urban woodland and/or the proportion of peri‐urban woodland, and a further eight species were associated with the interaction between these two factors. Local breeding bird abundances of four species were significantly positively associated with the proportion of urban woodland only in farmland‐dominated landscapes. Main conclusions Fragmentation effects on some urban birds are linked to the type of peri‐urban matrix. In farmland landscapes, peri‐urban woodlands may have been too scarce to act as a source of bird immigrants to fragmented urban woodlands. To maintain populations of specialized forest birds within cities in landscapes dominated by agriculture, it is of paramount importance to conserve any remaining urban woodlands.     

The urban heat island in a small city in coastal Portugal

This project arose from the need to study the phenomenon of the urban heat island, since only by recognising this phenomenon can we moderate it to improve the human and urban environments. Not only big cities develop urban heat islands. This study detected the presence and recorded the characteristics of an urban heat island in the small coastal city of Aveiro, Portugal. The study was developed through the scheduled measurements of air temperature and the analysis of the geographical, meteorological and urban conditions. The form and intensity of Aveiro’s heat island are a response to the interaction of three principal factors: the urban morphology (the hottest zones in the city are those with the tallest and the highest density of buildings, without green spaces and with intense generation of heat from traffic, commerce and services); the meteorological conditions (the intensity of the island is at its maximum when the sky is totally clear and there is no wind, and at its minimum in those situations when there is atmospheric instability, such as wind, cloud and precipitation); and the proximity of the coastal lagoon (which borders the city to the west and northwest and moderates seasonal temperatures. The urban heat island influences the comfort and health of its inhabitants, thus urban planning is very important in the moderation and prevention of this phenomenon. Received: 7 July 1999 / Revised: 24 April 2000 / Accepted: 26 April 2000     

哈尔滨市室外空气真菌组成和分布的初步研究

采用曝皿法(孟加拉红培养基)连续12个月对哈尔滨市实验林场、东北林业大学家属区和哈尔滨市二环路、兴路区间3个地点的空气真菌进行取样,初步确定了哈尔滨市室外空气真菌的种类及其动态变化。试验共得到9 908个真菌菌落,经鉴定为22属(或群)49种。试验结果表明:室外空气真菌的优势菌属依次为枝孢属、链格孢、曲霉属、青霉属、附球菌属、木霉属和无孢菌群,分别占总菌落数的21.54%、15.16%1、4.70%、12.20%、11.35%、7.86%和7.80%;室外空气真菌的种类在一天中基本没有变化,但菌落的数量有一定变化,总菌落数从早至晚也逐渐增加;不同季节室外真菌的种类和菌落数有明显变化,秋季最多,冬季最少;不同采样地点的空气真菌的种类变化不大,但菌落数量有差异,菌落数量依次为公路林场家属区。     

Eco-efficiency of urban material metabolism: a case study in Shenzhen, China

The keys of studying urban sustainable development are material metabolism flux and efficiency. Metabolism flux of urban materials can only reflect the metabolism velocity, while its eco-efficiency can determine the metabolism capacity to support socio-economic development. The general model and the measure model of the eco-efficiency were set up, based on the source recycle (decreasing the consumption of crude resources) and the terminal recycle (decreasing the discharge of pollutants) of production and life. These models were employed to study material metabolism flux and efficiency in Shenzhen, China. Results showed that water, energy and waste metabolism fluxes have increased since 1998 with constant socio-economic development, and their eco-efficiencies have also increased rapidly. When GDP rose by 2.7 times, the metabolism fluxes of urban water and electricity rose by 1.5 and 3.0 times, respectively. When the added value of industry rose by 3.7 times, the metabolism fluxes of industrial water, electricity, energy and waste rose by 1.9, 3.5, 2.7 and 2.0 times, respectively. When population rose by 1.5 times, the metabolism fluxes of residential water and electricity rose by 1.8 and 1.7 times, respectively. During the period, the resource efficiency, environmental efficiency and eco-efficiency rose by 1.8, 3.7 and 2.3 times, respectively. Whereas the efficiency of material metabolism has been improved in Shenzhen, the scarcity of material resources has become more and more serious. Therefore, it is necessary to further improve the efficiency of material metabolism. The keys of improving the eco-efficiency of urban material metabolism are the increasing of resource and environmental efficiencies, and the establishing of the recycling chain of re-utilization of waste resources.     

‘Race’, community and ongoing conflict

This review explores Rex and Moore's (1967) study of Birmingham as an enduring model of ethnic segregation, stratification, conflict and cooperation. The commentary focuses on the legacy of this research for understanding ethnic segregation, community and the city as a barometer of social change.     

深圳马峦山华南紫萁群落及其物种多样性特征研究

对深圳马峦山地区华南紫萁占优势的植物群落进行研究,结果表明：华南紫萁群落中共有维管植物48科69属82种,种类组成具有明显的南亚热带性质;年龄结构显示群落的主要优势种属于稳定型种群,群落总体处于稳定状态;群落的频度指数规律为A＞B＜C＞D＞E,与RaunKiaer频度定律、海南岛山地雨林优势种群的频度规律等不相符合;华南紫萁种群树高和个体数百分比显示,种群高度0.3~0.7 m植株占比例较大,种群处于旺盛发展期;物种多样性指数为SP＝16.42,SW＝4.56,均匀度指数为E＝0.33,E′＝0.83,群落物种多样性指数和均匀度指数均较高,接近典型南亚热带常绿阔叶林顶极群落类型。本研究揭示了华南紫萁野外生存状态,为该种的保护和利用提供了基础资料。     

张家界市部分农作物可食部位硒含量研究

采用国家标准( GB/T5009.93-2003),用荧光分光光度计对张家界市22种农作物40个样本可食部位中的硒含量进行了分析.结果表明,测定的22个种类40个样本均属于富硒及高硒作物,以茶叶的硒平均含量最高为2.0102 mg/kg,其次是豆类平均含量为1.8518 mg/kg,薯类含量最低为1.0240 mg/kg.所测定的各种作物可食部位富硒能力依次为:茶叶2.0102 mg/kg＞豆类(干)1.8518 mg/kg＞水稻、玉米1.5326 mg/kg＞蔬菜类1.3438 mg/kg＞水果类1.0783 mg/kg＞薯类1.0240 mg/kg.该研究确定了部分农作物硒含量的水平及富硒作物品种.