Urban green space, street tree and heritage large tree assessment in Bangkok, Thailand

Three inventories were conducted to quantify Bangkok's green infrastructure for future planning and improvement in the context of a seasonal monsoonal dry climate. Total green space was quantified by extracting surface cover areas from remotely sensed data in a geographical information system (GIS) environment, and this information was used to designate suitable sites for future green spaces such as parks. Street trees were inventoried for species identification and size. Trees of heritage value were identified through a public awareness campaign, and then were subsequently surveyed for species identification, height and trunk diameter. GIS green space analysis showed that per capita park space was approximately 1.8 m², but a master plan proposed increasing per capita park area to 4 m² within 25 years. The increased park area will be largely in the form of lower cost, semi-naturalized tree parks. The inventoried street tree population, approximately 200,000, was skewed somewhat towards a monoculture, as 42% were the facultative evergreen Pterocarpus indicus Wild. By contrast, none of the other species exceeded 7% of the total. That most of the other species consisted of smaller trunk diameters than P. indicus, and therefore younger, suggests that Bangkok's street tree plantings are becoming more diverse. The heritage large tree inventory was dominated by evergreen tree species, particularly exceptionally large Ficus species, found largely on Buddhist temple grounds, followed by Albizia saman (Jacq.) Merr. The slower growing evergreen heritage species are worth careful appraisal and preservation because they are less likely to be commonly planted. Careful species selection balancing drought deciduous and dry evergreen species can achieve adaptation to the monsoonal dry season with diverse aesthetic quality in both Bangkok's street tree population and in its semi-naturalized tree parks.     

Chronic toxicity of tributyltin to Chesapeake bay biota

Chronic tributyltin toxicity experiments were conducted with the following Chesapeake Bay organisms: amphipod, Gammarus sp.; juvenile Atlantic menhaden, Brevoortia tyrannus and larval inland silverside, Menidia beryllina. TBT concentrations ranging from 29 to 579 ng L^?1 did not significantly affect survival of the benthic amphipod, Gammarus sp. after 24-d exposures. The weight of Gammarus exposed to control conditions was 2.8 times greater than the weight of these test organisms exposed to 579 ng L^?1 TBT. Twenty-eight day exposures to TBT concentrations of 93 and 490 ng L^?1 did not significantly affect survival of juvenile B. tyrannus or larval M. beryllina. Histological examinations of B. tyrannus did not demonstrate absolute effects resulting from TBT exposure due to extensive variation between individuals. Various morphometric measurements of M. beryllina after TBT exposure did not demonstrate significant effects. However, significant reductions in growth were reported for M. beryllina at both TBT concentrations. Environmental concentrations of TBT in Chesapeake Bay and possible effects on the above biota are discussed.     

The ecological effectiveness of protected areas: The United Kingdom

Given the importance placed on protected areas, determining their effectiveness in representing and maintaining biodiversity is a core issue in conservation biology. Nonetheless, frameworks identifying the breadth of issues associated with this effectiveness, and case studies of how well these are understood in particular regions, remain lacking. In this paper, we provide such a framework and an overview of the current state of knowledge of the ecological effectiveness of protected areas in the United Kingdom. Arguably, better data are available to address such issues in this region than anywhere else in the world. Nonetheless, studies remain scarce and have focussed foremost on the, rather narrow, issue of the effectiveness of management actions on individual sites in order to deliver fixed conservation objectives and discharge statutory responsibilities. Some attention has also been paid to how well the regional collection or portfolio of protected areas performs, particularly in capturing biodiversity features. Work on the extent to which protected areas in the United Kingdom form effective functional networks is in its infancy, but initiatives are under development. We identify some of the questions about the effectiveness of protected areas to which answers need to be known at the site, portfolio and network levels, and how significant progress might be achieved in addressing these.     

湖南省邓恩桉与柳桉高产纤维材引种培育研究进展

中国大多数桉树资源主要集中在较为温暖的沿海地区.目前在湖南和江西等华南和中南省份较为冷凉的内陆地区,通过选择一些合适的耐寒桉树品种,种植了一些规模不大的桉树人工示范林,这些示范林显示出了较好的适应性与丰产性.这些较为冷凉的内陆地区有着立地条件较为优越的适合人工林发展的广大林地.对于较冷地区,尤其是湖南省来说,通过分析所...     

Further assessment of houseflies (Musca domestica) as vectors for the mechanical transport and transmission of porcine reproductive and respiratory syndrome virus under field conditions

The purpose of this study was to evaluate the potential for houseflies (Musca domestica) to mechanically transport and transmit porcine reproductive and respiratory syndrome virus (PRRSV) between pig populations under controlled field conditions. The study employed swine housed in commercial livestock facilities and a release-recapture protocol involving marked (ochre-eyed) houseflies. To assess whether transport of PRRSV by insects occurred, ochre-eyed houseflies were released and collected from a facility housing an experimentally PRRSV-inoculated population of pigs (facility A) and collected from a neighboring facility located 120 m to the northwest that housed a naïve pig population (facility B). All samples were tested for PRRSV RNA by polymerase chain reaction (PCR). To assess transmission between the 2 populations, blood samples were collected from naïve pigs in facility B at designated intervals and tested by PCR. A total of 7 replicates were conducted. During 2 of 7 replicates (1 and 5), PCR-positive ochre-eyed houseflies were recovered in facility B and pigs in this facility became infected with PRRSV. Chi-squared analysis indicated that the presence of PRRSV in an insect sample was significantly (P = 0.0004) associated with infection of facility B pigs. Porcine reproductive and respiratory syndrome virus was not recovered from other reported routes of transmission during the study period, including air, fomites, and personnel. In conclusion, while an insufficient number of replicates were conducted to predict the frequency of the event, houseflies may pose some level of risk for the transport and transmission of PRRSV between pig populations under field conditions.     

The effects of canine bone marrow stromal cells on neuritogenesis from dorsal root ganglion neurons in vitro

The present in vitro study was designed to evaluate whether canine bone marrow stromal cells (BMSCs) promote neurite outgrowth from dorsal root ganglion (DRG) neurons. Bone marrow aspirates were collected from iliac crests of three young adult dogs. DRG neurons were cultured on BMSCs, fibroblasts, or laminin substrates. DRG neurons were also cultured in BMSC- or fibroblast-conditioned media. DRG neurons grown on BMSCs extended longer neurites and developed a much more elaborate conformation of branching neurites compared to those on fibroblasts or laminin. Quantitative analysis revealed that these effects were associated with the emergence of increased numbers of primary and branching neurites. The effect appears to be dependent upon cell-cell interactions rather than by elaboration of diffusible molecules. With more extensive investigations into the basic biology of canine BMSCs, their ability for promoting neurite outgrowth may be translated into a novel therapeutic strategy for dogs with a variety of neurological disorders.     

Identification of immunogenic proteins associated with protection against haemorrhagic septicaemia after vaccination of calves with a live-attenuated aroA derivative of Pasteurella multocida B:2

Pasteurella multocida serotype B:2 is the causative agent of haemorrhagic septicaemia (HS), a fatal disease of cattle and buffaloes. As a step towards the identification of individual antigens that may protect against HS, proteins present in a sonicated cell extract (SCE) and outer-membrane protein (OMP) preparation of a wild-type P. multocida serotype B:2 were investigated by immunoblotting with sera from calves which had been protected against challenge with a virulent strain of P. multocida B:2 by vaccination with a live-attenuated aroA derivative of the challenge strain. Five proteins in SCE, of approximately 50, 37, 30, 26 and 16 kDa, were recognised by the sera. In an OMP preparation, two bands, at 37 and 50 kDa, were recognised as strongly immunogenic. Mass spectrometry analysis of proteins corresponding in size to those detected by immunoblotting identified the 37 kDa band as OmpA, but the band at 50 kDa was not identified with certainty. A major 30 kDa OMP, identified as OmpH, was not strongly immunogenic.