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521.
Joon Seok Kong Oh Hyun Kim Hyun Youk Hee Young Lee Chan Young Kang Sil Sung 《Traffic injury prevention》2018,19(8):S151-S153
AbstractObjective: The purpose of this study is to investigate the injury patterns of noncatastrophic accidents by individual age groups.Methods: Data were collected from the Korean In-Depth Accident Study database based on actual accident investigation. The noncatastrophic criteria were classified according to U.S. experts from the Centers for Disease Control and Prevention’s recommendations for field triage guidelines of high-risk automobile crash criteria by vehicle intrusions more than 12 in. on occupant sites (including the roof) and more than 18 in. on any site. The Abbreviated Injury Scale (AIS) was used to determine injury patterns for each body region. Severely injured patients were classified as Maximum Abbreviated Injury Scale (MAIS) 3 or higher.Results: In this study, the most significant injury regions were the head and neck, extremities, and thorax. In addition, the incidence of severe injury among elderly patients was nearly 1.6 times higher than that of non-elderly patients. According to age group, injured body regions among the elderly were the thorax, head and neck, and extremities, in that order. For the non-elderly groups, these were head and neck, extremities, and thorax. Severe injury rates were slightly different for the elderly group (head and neck, abdomen) and non-elderly group (thorax, head and neck).Conclusions: In both age groups, the rate of severe injury is proportional to an increase in crush extent zone. Front airbag deployment may have a relatively significant relationship to severe injuries. 相似文献
522.
Implications of Land Use/Land Cover Change in the Buffer Zone of a National Park in the Tropical Andes 总被引:2,自引:0,他引:2
The impacts of land use and land cover (LULC) change in buffer zones surrounding protected ecological reserves have important
implications for the management and conservation of these protected areas. This study examines the spatial and temporal patterns
of LULC change along the boundary of Rio Abiseo National Park in the Northern Peruvian Andes. Landscape change within four
ecological zones was evaluated based on trends expected to occur between 1987 and 2001. Landsat TM and ETM imagery were used
to produce LULC classification maps for both years using a hybrid supervised/unsupervised approach. LULC changes were measured
using landscape metrics and from-to change maps created by post-classification change detection. Contrary to expectations,
tropical upper wet montane forest increased despite being threatened by human-induced fires and cattle grazing of the highland
grasslands inside the park. Within the park’s buffer zone, tropical moist forest remnants were fragmented into more numerous
and smaller patches between 1987 and 2001; this was in part due to conversion into agricultural land. The methods used in
this study provide an effective way to monitor LULC change detection and support the management of protected areas and their
surrounding environments. 相似文献
523.
K. J. Eckelbarger C. M. Young E. Ramirez Llodra S. Brooke P. Tyler 《Marine Biology》2001,138(4):761-775
Gametogenesis, spawning behavior, and early development have been described in the methane-seep polychaete Hesiocaecamethanicola Desbruyères and Toulmond, 1998, the first documentation of the reproductive biology of any cold-seep polychaete species.
The worms were collected at the Green Canyon site in the Gulf of Mexico (27°44.77N; 91°13.33W) in August 1997. The gonads
are situated in the neuropodia in association with an intraepithelial capillary system. Oogenesis is intraovarian, with oocytes
remaining in the ovary until late vitellogenesis when they are released into the coelom for final growth and differentiation.
Vitellogenesis involves both autosynthetic and heterosynthetic processes and, along with ovarian structure, suggests a relatively
slow process of egg formation. Sperm differentiation is intertesticular until early spermiogenesis, when spermatid tetrads
complete development in the coelom. The mature spermatozoon is an ect-aquasperm consisting of a tapering, digitate acrosome,
a spherical nucleus, a midpiece containing from six to eight mitochondria and glycogen stores, and two centrioles associated
with the flagellum. Both sexes undergo broadcast spawning, but the males spawn exclusively through the anus, a behavior previously
unknown in polychaetes. Artificial fertilization resulted in spiral cleavage and development to the trochophore stage. Oocyte
size-frequency analysis of adult females indicates a wide range of oocyte sizes and vitellogenic stages, suggesting that asynchronous
gametogenesis occurs.
Received: 13 July 2000 / Accepted: 29 November 2000 相似文献
524.
Bruce E. Young †††† Karen R. Lips † Jamie K. Reaser ‡ Roberto Ibáñez § Antonio W. Salas J. Rogelio Cedeño †† Luis A. Coloma ‡‡ Santiago Ron ‡‡ Enrique La Marca §§ John R. Meyer Antonio Muñoz ††† Federico Bolaños ‡‡‡ Gerardo Chaves ‡‡‡ David Romo§§§ 《Conservation biology》2001,15(5):1213-1223
Abstract: Although dramatic amphibian population declines have been reported worldwide, our understanding of the extent of the declines in Latin America, where amphibian diversity is high, is limited to a few well-documented studies. To better understand the geographic extent of declines, their possible causes, and the measures needed to improve Latin American scientists' ability to research the phenomenon and make effective management recommendations, we convened three regional workshops with 88 Latin American herpetologists and conservationists. Population declines are widespread in Latin America. At least 13 countries have experienced declines, and in 40 cases species are now thought to be extinct or extirpated in a country where they once occurred. Declines or extinctions have affected 30 genera and nine families of amphibians. Most declines have occurred in remote highlands, above 500 m in elevation in Central America and above 1000 m in the Andes. Most documented declines occurred in the 1980s. Of the possible causes studied to date, climate change appears to be important at one site and chytrid fungal disease has been identified at sites in three countries. Although many monitoring studies are currently underway in a variety of habitats, most studies are recent and of short duration. In a signed resolution, workshop participants called for greater collaboration and communication among scientists working in Latin America to understand the geographic extent of population declines and the distribution of possible causal factors. In situ conservation is important to protect habitats, but captive-rearing programs for species subject to imminent extinction are also needed. Better understanding of the taxonomy and natural history of amphibians and more funding for research and monitoring are critical to developing a scientific basis for management action to arrest and reverse population declines. 相似文献
525.
Maxted AP Black CR West HM Crout NM McGrath SP Young SD 《Environmental pollution (Barking, Essex : 1987)》2007,150(3):363-372
The objectives of this study were to assess the potential for using Thlaspi caerulescens as a phytoextraction plant and develop a user-advice model, which can predict the frequency of phytoextraction operation required under prescribed conditions. Pot and field trials were conducted using soil collected from a dedicated sewage sludge disposal facility. Soil amendments (sulphuric acid, potassium chloride and EDTA) intended to increase Cd solubility were also tested. Predictive models of Cd and Zn uptake were developed which were able to reproduce the observed pH-dependence of Cd uptake with an apparent maximum around pH 6. Chemical treatments did not significantly increase the uptake of Cd. The periodic use of phytoextraction with T. caerulescens to maintain soils below statutory metal concentration limits, when modern sewage sludges are repeatedly applied, seems very attractive given the non-intrusive and cost-effective nature of the process. The major limitations lie with the large-scale husbandry of T. caerulescens. 相似文献
526.
To analyze polycyclic aromatic hydrocarbons (PAHs) at an urban site in Seoul, South Korea, 24-hr ambient air PM2.5 samples were collected during five intensive sampling periods between November 1998 and December 1999. To determine the PAH
size distribution, 3-day size-segregated aerosol samples were also collected in December 1999. Concentrations of the 16 PAHs
in the PM2.5 particles ranged from 3.9 to 119.9 ng m−3 with a mean of 24.3 ng m−3.An exceptionally high concentration of PAHs(∼120 ng m−3) observed during a haze event in December 1999 was likely influenced more by diesel vehicle exhaust than by gasoline exhaust,
as well as air stagnation, as evidenced by the low carbon monoxide/elemental carbon (CO/EC) ratio of 205 found in this study
and results reported by previous studies.
The total PAHs associated with the size-segregated particles showed unimodal distributions. Compared to the unimodal size
distributions of PAHs with modal peaks at < 0.12 μm measured in highway tunnels in Los Angeles (Venkataraman and Friedlander,
1994), four- to six-ring PAHs in our study had unimodal size distributions, peaking at the larger size range of 0.28–0.53
μm, suggesting the coagulation of freshly emitted ultrafine particles during transport to the sampling site. Further, the
fraction of PAHs associated with coarse particles(> 1.8 μm) increased as the molecular weight of the PAHs decreased due to
volatilization of fine particles followed by condensation onto coarse particles. 相似文献
527.
This study investigated the reforming characteristics and optimum operating condition of the high-temperature plasma torch (so called plasmatron) for hydrogen-rich gas (syngas) production. At the optimum condition, the composition of produced syngas was 45.4% hydrogen (H2), 6.9% carbon monoxide (CO), 1.5% carbon dioxide (CO2), and 1.1% acetylene (C2H2). The H2/CO ratio was 6.6, hydrogen yield was 78.8%, and the energy conversion rate was 63.6%. To obtain the optimum operating condition, parametric studies were carried out examining the effects of O2/CH4 ratio, steam/CH4 ratio, and Ni catalyst addition in reactor. When the steam/CH4 ratio was 1.23, the production of hydrogen was maximized and the methane conversion rate was 99.7%. The syngas composition was determined to be 50.4% H2, 5.7% CO, 13.8% CO2, and 1.1% C2H2. The H2/CO ratio was 9.7, hydrogen yield was 93.7%, and the energy conversion rate was 78.8%. Hydrogen production with catalyst was effective, compared with no catalyst. 相似文献
528.
529.
Jessica Betts Richard P. Young Craig Hilton-Taylor Michael Hoffmann Jon Paul Rodríguez Simon N. Stuart E.J. Milner-Gulland 《Conservation biology》2020,34(3):632-643
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, a species extinction risk assessment tool, has been guiding conservation efforts for over 5 decades. It is widely assumed to have been instrumental in preventing species from moving closer to extinction and driving recoveries. However, the impact of the IUCN Red List in guiding conservation has not been evaluated. We conducted, transcribed, and coded interviews with experts who use the IUCN Red List across a range of sectors to understand how the list is used in conservation. We developed a theory of change to illustrate how and why change is expected to occur along causal pathways contributing to the long-term goal of the IUCN Red List and an evaluation framework with indicators for measuring the impact of the IUCN Red List in generating scientific knowledge, raising awareness among stakeholders, designating priority conservation sites, allocating funding and resources, influencing development of legislation and policy, and guiding targeted conservation action (key themes). Red-list assessments were the primary input leading to outputs (scientific knowledge, raised awareness), outcomes (better informed priority setting, access to funding and resource availability, improved legislation and policy), and impact (implemented conservation action leading to positive change) that have resulted in achievement of IUCN Red List goals. To explore feasibility of attributing the difference made by the IUCN Red List across themes, we studied increased scientific knowledge, raised awareness, access to funding and resource allocation, and increased conservation activity. The feasibility exploration showed increased scientific knowledge over time identified through positive trends in publications referring to the IUCN Red List in the literature; raised awareness of the list following high IUCN activity identified by peaks in online search activity; an increased proportion of conservation funding bodies requesting IUCN Red List status in the application process; and, based on interviews with Amphibian Specialist Group members, red-list assessments were essential in connecting relevant stakeholders and ensuring conservation action. Although we identified the IUCN Red List as a vital tool in global conservation efforts, it was challenging to measure specific impacts because of its ubiquitous nature. We are the first to identify the influence of the IUCN Red List on conservation. 相似文献
530.
Satnam Singh Li-Sen Young Fo-Ting Shen Chiu-Chung Young 《Waste management (New York, N.Y.)》2014,34(10):1877-1883
Discharging untreated highly acidic (pH < 4.0), organic and nutrients rich monosodium glutamate wastewater (MW), and highly alkaline (pH > 10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5 ± 0.1) with PW and lime (treatments represented as MW + PW and MW + Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha?1. Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear?1 and 100-kernel weight were higher in MW + Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW + Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW + PW. The MW + PW and MW + Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances. 相似文献