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281.
282.
Doucet JJ Hill L Stout P Bansal V Lee J Fortlage D Potenza B Workman P Coimbra R 《Journal of Safety Research》2011,42(2):131-135
Objective
Pedicabs are a new and controversial transportation innovation for tourists in congested areas in several U.S. cities. Scant literature on this trauma mechanism exists. The purpose of this study is to identify the incidence, demographics, morbidity, mortality, and potential for injury prevention of pedicab incidents amongst major trauma admissions at an urban, academic Level I Trauma Center.Patients & Methods
Researchers conducted a retrospective review of the Trauma Registry from 2000 to 2009. All patients identified as being injured in a pedicab incident were reviewed. Demographics, diagnoses, toxicology, treatments, and injury severity scale (ISS) were collected. Outcomes included mortality, ICU, and hospital length of stay (LOS), discharge disposition, and hospital charges. A photographic survey of 50 local pedicabs was examined for the presence and use of safety equipment.Results
During the period of January 2000 to July 2009 there were 15 major trauma victims from identified pedicab incidents. Falling from the pedicab was the mechanism of injury in 14 of 15 cases. There were two fatalities in victims following severe traumatic brain injury. Traumatic brain injury, skull fracture, or loss of consciousness was seen in 11/15 victims. Ethanol ingestion was detected in blood tests of 10 of the 14 adult victims. Median charges of hospitalization due to a pedicab related injury was US$29,956 ± 77,482. A photographic survey of 50 local pedicabs reveals very limited use of safety belts by passengers despite existing city ordinances.Conclusions
Major trauma victims of pedicab incidents in the United States suffer significant injuries and death. Most cases occurred in passengers falling from the pedicab at night after alcohol ingestion. There is an opportunity for implementation of strategies toward improved injury prevention with this new form of transport. 相似文献283.
Accurate species identification is the cornerstone of any ecological study - yet this fundamental step is not always possible for marine zooplankton. Routine species' identification, especially of juvenile andlarval stages, is difficult for Calanus species (Copepoda; Calanoida) in the N. Atlantic Ocean, where two or three species may co-occur. A rapid, simple, and inexpensive molecularly based protocol to identify individual copepods of any life stage has beendeveloped. This protocol will routinely identify four Calanus species in the N. Atlantic and will help to accurately understand the role of each species in coastal and open ocean ecosystems. The DNA sequence of a 633 bp region of the mitochondrial cytochrome oxidase I (mtCOI) was determined for ten Calanus species: C. australis (Brodsky, 1959), C. chilensis (Brodsky, 1959), C. finmarchicus (Gunnerus, 1770), C. glacialis (Jaschnov, 1955), C. helgolandicus (Claus, 1863), C. hyperboreus (Krøyer, 1838), C. marshallae (Frost, 1974), C. pacificus (Brodsky, 1948), C. simillimus (Giesbrecht, 1902), and C. sinicus (Brodsky, 1965). MtCOI sequences were used to design species-specific oligonucleotide primers for C. finmarchicus, C. glacialis, C. helgolandicus, and C. hyperboreus and to optimize a competitive, multiplexed, species-specific PCR (SS-PCR) protocol to discriminate the four species. This corrects and improves a previously published protocol for three Calanus species (Bucklin et al. 1999: Hydrobiologia 401:239-254), unambiguously identifying individual copepods and copepodites from diverse geographic regions of the four species' ranges. In order to further examine the pattern of mtCOI evolution within Calanus (an important consideration for molecular systematic characters), consensus mtCOI sequences were used to reconstruct phylogenetic relationships among the ten species; the mtCOI gene tree agreed with morphological and molecular (based on mt16S rRNA) phylogenies, except that the affiliation of C. sinicus could not be resolved. 相似文献
284.
Wiebke E. Krämer Verena Schrameyer Ross Hill Peter J. Ralph Kai Bischof 《Marine Biology》2013,160(3):563-577
This study examined the capacity for photoprotection and repair of photo-inactivated photosystem II in the same Symbiodinium clade associated with two coexisting coral species during high-light stress in order to test for the modulation of the symbiont’s photobiological response by the coral host. After 4 days exposure to in situ irradiance, symbionts of the bleaching-sensitive Pocillopora damicornis showed rapid synthesis of photoprotective pigments (by 44 %) and strongly enhanced rates of xanthophyll cycling (by 446 %) while being insufficient to prevent photoinhibition (sustained loss in F v/F m at night) and loss of symbionts after 4 days. By contrast, Pavona decussata showed no significant changes in F v/F m, symbiont density or xanthophyll cycling. Given the association with the same Symbiodinium clade in both coral species, our findings suggest that symbionts in the two species examined may experience different in hospite light conditions as a result of different biometric properties of the coral host. 相似文献
285.
Geoffrey B. Hill Susan A. Baldwin Bjorn Vinnerås 《Waste management (New York, N.Y.)》2013,33(7):1602-1606
It is challenging and expensive to monitor and test decentralized composting toilet systems, yet critical to prevent the mismanagement of potentially harmful and pathogenic end-product. Recent studies indicate that mixed latrine composting toilets can be inhibited by high ammonia content, a product of urea hydrolysis. Urine-diverting vermicomposting toilets are better able to accomplish the goals of remote site human waste management by facilitating the consumption of fecal matter by earthworms, which are highly sensitive to ammonia. The reliability of Solvita® compost stability and maturity tests were evaluated as a means of determining feedstock suitability for vermicomposting (ammonia) and end-product stability/completeness (carbon dioxide). A significant linear regression between Solvita® ammonia and free ammonia gas was found. Solvita® ranking of maturity did not correspond to ranking assigned by ammonium:nitrate standards. Solvita® ammonia values 4 and 5 contained ammonia levels below earthworm toxicity limits in 80% and 100% of samples respectively indicative of their use in evaluating feedstock suitability for vermicomposting. Solvita® stability tests did not correlate with carbon dioxide evolution tests nor ranking of stability by the same test, presumably due to in situ inhibition of decomposition and microbial respiration by ammonia which were reported by the Solvita® CO2 test as having high stability values. 相似文献
286.
B. D. Hill D. J. Inaba D. L. Johnson 《Journal of environmental science and health. Part. B》2013,48(5):601-617
Abstract The mean amount of deltamethrin deposited on natural substrates (i.e., soil and vegetation) in three experiments was 63, 73, and 76% of applied. Composite samples taken from 16 sites/replicate gave representative and repeatable measures of deposition. The use of Teflon discs as artificial targets to measure aerial deposition was investigated. The discs had only 34–71% mean trapping efficiency for the spray droplets. Deposition was quite variable among different sampling sites within a field (CV=73–83%). Much of this variation was caused by irregular overlapping of spray swaths. 相似文献
287.
288.
A. Garg R. Smith D. Hill P.J. Longhurst S.J.T. Pollard N.J. Simms 《Waste management (New York, N.Y.)》2009,29(8):2289-2297
This paper reports an integrated appraisal of options for utilising solid recovered fuels (SRF) (derived from municipal solid waste, MSW) in energy intensive industries within the United Kingdom (UK). Four potential co-combustion scenarios have been identified following discussions with industry stakeholders. These scenarios have been evaluated using (a) an existing energy and mass flow framework model, (b) a semi-quantitative risk analysis, (c) an environmental assessment and (d) a financial assessment. A summary of results from these evaluations for the four different scenarios is presented. For the given ranges of assumptions; SRF co-combustion with coal in cement kilns was found to be the optimal scenario followed by co-combustion of SRF in coal-fired power plants. The biogenic fraction in SRF (ca. 70%) reduces greenhouse gas (GHG) emissions significantly (~2500 g CO2 eqvt./kg DS SRF in co-fired cement kilns and ~1500 g CO2 eqvt./kg DS SRF in co-fired power plants). Potential reductions in electricity or heat production occurred through using a lower calorific value (CV) fuel. This could be compensated for by savings in fuel costs (from SRF having a gate fee) and grants aimed at reducing GHG emission to encourage the use of fuels with high biomass fractions. Total revenues generated from coal-fired power plants appear to be the highest (£95/t SRF) from the four scenarios. However overall, cement kilns appear to be the best option due to the low technological risks, environmental emissions and fuel cost. Additionally, cement kiln operators have good experience of handling waste derived fuels. The scenarios involving co-combustion of SRF with MSW and biomass were less favourable due to higher environmental risks and technical issues. 相似文献
289.
290.
A mechanism for horizontal zooplankton transport by vertical migration in tidal currents 总被引:2,自引:0,他引:2
A. E. Hill 《Marine Biology》1991,111(3):485-492
A mechanism is proposed by which net horizontal transport can be induced in an organism which migrates vertically in a purely oscillatory, vertically sheared tidal current. The mechanism contains two elements. First, for all reasonable tidal current profiles, net horizontal transport is induced in any organism which migrates vertically with a period which is an exact multiple of the tidal period. (This is the basis for the widelyknown process of selective tidal stream transport where the migration period and the tidal period are exactly equal.) The second element in the new mechanism is the observation that diel migration, the most common form of vertical migration, has a period of 24 h and is therefore an exact multiple of the principal solar semi-diurnal tidal constituent (S2) which has a period of 12 h. This relation between the S2 and diel migration periods stems from the fact that both phenomena are independently locked to the solar cycle. Diel vertical migration can therefore interact with the S2 tidal current constituent to induce longterm horizontal transport in migrating organisms. For reasonable tidal current and vertical migration parameters it is found that horizontal transport rates of 4 km d–1 are possible. The direction of net transport depends upon the phase of the S2 tidal current relative to local noon. The hypothesis is therefore proposed that geographical variation in S2 phase is a factor responsible for creating regions which are either retention-favorable or otherwise for diel-migrating marine organisms. 相似文献