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261.
The pelagic copepod Calanus pacificus ranges nearly continuously across temperate-boreal regions of the North Pacific Ocean and is currently divided into three
subspecies—C. pacificus oceanicus, C. pacificus californicus, C. pacificus pacificus—based on subtle morphological differences and geographic location. The relation between geography and genetic differentiation
was examined for 398 C. pacificus individuals sampled from six widely distributed locations across the North Pacific, including an open ocean site and coastal
sites on both sides of the North Pacific basin. For each individual copepod, the DNA sequence was determined for a 421-bp
region of the mitochondrial coxI gene (mtCOI). A total of sixty-three different mtCOI sequences, or haplotypes, were detected,
with a sequence divergence between haplotypes of 0.2–3.1%. The number and distribution of haplotypes varied with sampling
location; 12 haplotypes were distributed across multiple sampling locations, and 51 occurred at only one location. Five genetically
distinct populations were detected based on F
ST values. Haplotype minimum spanning networks, nucleotide divergence and F
ST values indicated that individuals from coastal sites in the North Pacific Ocean were more closely related to each other than
to individuals from the open ocean site at Station P. These results provide genetic support for the designation of two subspecies—a
coastal subspecies that consists of what is currently referred to as C. p. pacificus and C. p. californicus and an open ocean subspecies C. p. oceanicus. This work also indicates that planktonic copepods with potentially high dispersal capacity can develop genetically structured
populations in the absence of obvious geographic barriers between proximate locales within an ocean basin. 相似文献
262.
Bruce A. Hendry 《Environmental geochemistry and health》2010,32(4):353-359
This contribution to the International Congress on Production of Safe Water, Izmir, Turkey, 20–24 January, 2009, relates to
general aspects of a water supply undertaking rather than to particular technologies or chemistries for water treatment. The
paper offers a “creative problem solving” approach following Fogler and LeBlanc (Strategies for creative problem solving.
Prentice Hall, NJ, 1995) as a model for generating sustainable solutions when water quality and safety problems arise. Such a structured approach
presents a systematic methodology that can promote communication and goal-sharing across the inter-related, but often isolated
and dispersed, functions of water scientists and researchers, engineers, operations managers, government departments and communities.
A problem-solving strategy, or “heuristic”, invokes five main steps (define; generate; decide; implement; evaluate). Associated
with each step are various creative and enabling techniques, many of which are quite familiar to us in one form or another,
but which we can use more effectively in combination and through our increased awareness and practice. For example, taking
a fresh view of a problem can be promoted by a variety of “lateral thinking” tools. First-hand investigation of a problem
can trigger new thinking about the real problem and its origins. A good strategy implementation will always address each and every step (though not necessarily every possible technique) and will use them at various stages in the search for and implementation of solutions. The creative nature of our experience
with a problem-solving heuristic develops our facility to cope better with complex formal situations, as well as with less
formal or everyday problem situations. A few anecdotes are presented that illustrate some of the author’s experiences relating
to factors involved in safe water supply. Here, the term “factors” may signify people and organisations as agents, as well as meaning those aspects of a problem situation that need to be taken into account. 相似文献
263.
PROBLEM: While agricultural injury has been identified among the major causes of occupational injury mortality and morbidity, data have been limited pertinent to the magnitude, consequences, and potential risk factors for animal-related injuries -- a major source of morbidity among agricultural operations. METHODS: Demographics, exposure, and injury data were collected for 1999 and 2001 among agricultural households in a five-state region. Causal models facilitated survey design, data analyses, and interpretation of results; directed acyclic graphs guided multivariate modeling. RESULTS: From 7,420 households (84% response of eligible), a total of 5,045 injury events were reported; 1,016 (20.1%) were animal-related. Multivariate analyses revealed increased risks for those <20 years; residents of all states compared to Minnesota; all age groups compared to 0-4 years; >0 hours worked; and prior agricultural injury history. For those 20+ years, increased risks were identified for: South Dakota residents; males; >0 hours worked; and prior agricultural injury history. For those cases <20 and 20+ years of age, 58% and 46%, respectively, resulted in lost work time on their agricultural operations (31% and 50%, one week or more). CONCLUSIONS: Animal-related injury has a major impact on the agricultural industry. Results serve as a basis for interventions and further research. IMPACT ON INDUSTRY: The impact of animal-related injuries on the agricultural industry appears significant; among age groups <20 and 20+, 85% and 82%, respectively, had some resulting restriction. For all events combined, 29% and 30%, respectively, involved restriction from one week to 3+ months; 12% and 15% involved restriction for one month or more. Among those <20 and 20+ years of age, 58% and 46%, respectively, lost work time on their own agricultural operation as a result of injuries associated with their own operation; 22% and 15% lost one week or more. Moreover, of the non-agriculture-related injuries, 31% and 50% resulted in lost work time on their own operation; 15% and 28%, respectively, lost one week or more. Restrictions such as these can affect the productivity of the operation, resulting in financial impacts, especially on small operations that have few people to manage the required tasks. 相似文献
264.
The conditions that give rise to drinking and driving are complex, with multiple and interrelated causes. Prevention efforts benefit from an approach that relies on the combination of multiple interventions. Health promotion provides a useful framework for conceptualizing and implementing actions to reduce drinking and driving since it involves a combination of educational, behavioral, environmental, and policy approaches. This review draws on data from a range of settings to characterize the effectiveness of various interventions embedded within the health promotion approach. Interventions considered part of the health promotion approach include: (1) economic interventions (2) organizational interventions, (3) policy interventions, and (4) health education interventions, including the use of media, school and community education, and public awareness programs. Effective health promotion strengthens the skills and capabilities of individuals to take action and the capacity of groups or communities to act collectively to exert control over the determinants of alcohol-impaired driving. There is strong evidence for the effectiveness of some components of health promotion, including economic and retailer interventions, alcohol taxation, reducing alcohol availability, legal and legislative strategies, and strategies addressing the servers of alcohol. There is also evidence for the effectiveness of sobriety checkpoints, lower BAC laws, minimum legal drinking age laws, and supportive media promotion programs. Other interventions with moderate evidence of effectiveness include restricting alcohol advertising and promotion, and actions involving counter advertising. Health education interventions alone that have insufficient evidence for effectiveness include passive server training programs, school drug and alcohol education programs, community mobilization efforts, and health warnings. Because each intervention builds on the strengths of every other one, ecological approaches to reducing alcohol-impaired driving using all four components of the health promotion model are likely to be the most effective. Settings such as schools, workplaces, cities, and communities offer practical opportunities to implement alcohol-impaired driving prevention programs within this framework. 相似文献
265.
Shults RA Jones BH Kresnow MJ Langlois JA Guerrero JL 《Journal of Safety Research》2004,35(4):447-452
INTRODUCTION: Little population-based information exists about the long-term effects of motor-vehicle crash-related injuries. METHOD: We analyzed data from the 1995 National Health Interview Survey Disability (NHIS-D) Supplement to estimate the prevalence of crash-related disability among noninstitutionalized U.S. adults aged 18 years and older. RESULTS: More than 1.2 million adults were living in their homes with the disabling effects of motor-vehicle crash-related injuries in 1995. The prevalence of crash-related disability was highest for persons in their mid-life years, ages 35-64. Half of the respondents had sustained the injuries more than 5 years before the interview. Forty-one percent of working-aged individuals reported being unable to work because of their disability. CONCLUSIONS: Because crash-related disability is most prevalent during the mid-life years, quality of life and productivity may be affected for decades. These findings highlight the personal and societal burden associated with motor-vehicle crash-related disability in the United States. 相似文献
266.
Adriana María Albino Bruce Rothschild Jorge D. Carrillo-Briceño James M. Neenan 《Die Naturwissenschaften》2018,105(9-10):51
Inflammatory arthritis is documented for the first time in snakes. Ossification of the intervertebral capsule and zygapophyseal joints resulting in segmental vertebral fusion was observed in the aquatic Cretaceous snake Lunaophis aquaticus. Such pathologic alterations are pathognomonic for the spondyloarthropathy form of inflammatory arthritis. A survey of 2144 snakes in recent collections, performed to identify Holocene prevalence, revealed only two occurrences in extant snakes. The findings in Bitis gabonica and Elaphe taeniura were indistinguishable from those noted in Lunaophis aquaticus and identical to those previously recognized in modern varanids. The pathology likely represents a form of reactive arthritis related to enteropathic infection. While the disease probably did not affect general locomotion, its vertebral column position may have compromised mating. 相似文献
267.
Holly F. Swift William M. Hamner Bruce H. Robison Laurence P. Madin 《Marine Biology》2009,156(5):1049-1056
Behavioral observations using a remotely operated vehicle (ROV) in the Gulf of California in March, 2003, provided insights
into the vertical distribution, feeding and anatomy of the rare and delicate ctenophore Thalassocalyce inconstans. Additional archived ROV video records from the Monterey Bay Aquarium Research Institute of 288 sightings of T. inconstans and 2,437 individual observations of euphausiids in the Gulf of California and Monterey Canyon between 1989 and 2005 were
examined to determine ctenophore and euphausiid prey depth distributions with respect to temperature and dissolved oxygen
concentration [dO]. In the Gulf of California most ctenophores (96.9%) were above 350 m, the top of the oxygen minimum layer.
In Monterey Canyon the ctenophores were more widely distributed throughout the water column, including the hypoxic zone, to
depths as great as 3,500 m. Computer-aided behavioral analysis of two video records of the capture of euphausiids by T. inconstans showed that the ctenophore contracted its bell almost instantly (0.5 s), transforming its flattened, hemispherical resting
shape into a closed bi-lobed globe in which seawater and prey were engulfed. Euphausiids entrapped within the globe displayed
a previously undescribed escape response for krill (‘probing behavior’), in which they hovered and gently probed the inner
surfaces of the globe with antennae without stimulating further contraction by the ctenophore. Such rapid bell contraction
could be effected only by a peripheral sphincter muscle even though the presence of circumferential ring musculature was unknown
for the Phylum Ctenophora. Thereafter, several live T. inconstans were collected by hand off Barbados and microscopic observations confirmed that assumption. 相似文献
268.
Dhazn Gillig Bruce A. McCarl Ronald D. Sands 《Mitigation and Adaptation Strategies for Global Change》2004,9(3):241-259
An econometrically estimated family ofresponse functions is developed forcharacterizing potential responses togreenhouse gas mitigation policies by theagriculture and forestry sectors in theU.S. The response functions are estimatedbased on results of anagricultural/forestry sector model. Theyprovide estimates of sequestration andemission reductions in forestry andagriculture along with levels of sectoralproduction, prices, welfare, andenvironmental attributes given a carbonprice, levels of demand for agriculturalgoods, and the energy price. Sixalternative mitigation policiesrepresenting types of greenhouse gasoffsets allowed are considered. Resultsindicate that the largest quantity ofgreenhouse gas offset consistently appearswith the mitigation policy that pays forall opportunities. Restricting carbonpayments (emission tax or sequestrationsubsidy) only to aff/deforestation or onlyto agricultural sequestration substantiallyreduces potential mitigation. Highercarbon prices lead to more sequestration,less emissions, reduced consumer and totalwelfare, improved environmental indicatorsand increased producer welfare. 相似文献
269.
As one of the transition metals, vanadium(V)(V(V)) in trace amounts represents an essential element for normal cell growth, but becomes toxic when its concentration is above 1 mg/L. V(V) can alter cellular differentiation, gene expression, and other biochemical and metabolic phenomena. A feasible method to detoxify V(V) is to reduce it to V(IV), which precipitates and can be readily removed from the water. The bioreduction of V(V) in a contaminated groundwater was investigated using autohydrogentrophic bacteria and hydrogen gas as the electron donor. Compared with the previous organic donors,H2 shows the advantages as an ideal electron donor, including nontoxicity and less production of excess biomass. V(V) was 95.5% removed by biochemical reduction when autohydrogentrophic bacteria and hydrogen were both present, and the reduced V(IV)precipitated, leading to total-V removal. Reduction kinetics could be described by a first-order model and were sensitive to p H and temperature, with the optimum ranges of p H 7.5–8.0 and 35–40°C, respectively. Phylogenetic analysis by clone library showed that the dominant species in the experiments with V(V) bioreduction belonged to theβ-Proteobacteria. Previously known V(V)-reducing species were absent, suggesting that V(V)reduction was carried out by novel species. Their selective enrichment during V(V)bioreduction suggests that Rhodocyclus, a denitrifying bacterium, and Clostridium, a fermenter known to carry out metal reduction, were responsible for V(V) bioreduction. 相似文献
270.
Shunan Shan Yuting Zhang Yining Zhang Lanjun Hui Wen Shi Yongming Zhang Bruce E. Rittmann 《Frontiers of Environmental Science & Engineering》2017,11(6):8
Benzotriazole (BTA) is an emerging contaminant that also is a recalcitrant compound. Sequential and intimate coupling of UV-photolysis with biodegradation were investigated for their impacts on BTA removal and mineralization in aerobic batch experiments. Special attention was given to the role of its main photolytic products, which were aminophenol (AP), formic acid (FA), maleic acid (MA), and phenazine (PHZ). Experiments with sequential coupling showed that BTA biodegradation was accelerated by photolytic pretreatment up to 9 min, but BTA biodegradation was slowed with longer photolysis. FA and MA accelerated BTA biodegradation by being labile electron-donor substrates, but AP and PHZ slowed the rate because of inhibition due to their competition for intracellular electron donor. Because more AP and PHZ accumulated with increasing photolysis time, their inhibitory effects began to dominate with longer photolysis time. Intimately coupling photolysis with biodegradation relieved the inhibition effect, because AP and PHZ were quickly biodegraded and did not accumulate, which accentuated the beneficial effect of FA and MA.
相似文献