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481.
Braver ER Kufera JA Volpini KD Lawpoolsri S Joyce JJ Alexander MT Ellison-Potter P 《Traffic injury prevention》2007,8(1):39-46
OBJECTIVE: This study aimed to determine whether a persuasive educational intervention could increase licensure among motorcycle owners. Unlicensed motorcycle operators appear to be disproportionately involved in police-reported motorcycle crashes in Maryland, accounting for about 27% of motorcycle operators in police-reported crashes, although unlicensed owners comprise 17% of primary motorcycle owners. METHODS: A randomized controlled trial was conducted among unlicensed owners. Linking Maryland records of registered motorcycles with license files, 8,499 unlicensed owners who had no licensed co-owners were identified. Half were randomized to receive a persuasive educational mailing in early June 2005 from Maryland Motor Vehicle Administration (MVA). Motorcycle licenses can be attained by passing an accredited motorcycle training class or passing knowledge and skills tests administered by the state driver licensing agency. Licensure rates and motorcycle class enrollment were followed for 6 months post-intervention. RESULTS: As of December 16, 2005, 280 intervention group owners had obtained Class M motorcycle licenses and 158 had obtained Class R motorcycle learner's permits. The comparison group obtained 209 M licenses and 122 R permits. The overall success rate in the intervention group, defined as obtaining Class M or R, was 10.4% compared with 7.9% in the comparison group (licensure ratio (LR) = 1.33; 95% confidence interval (CI) = 1.16-1.52). The intervention was most successful among men, whose LR for obtaining M licenses was 1.45 (95% CI = 1.21-1.75). LRs were higher among owners ages 40-48 and 49+ receiving the intervention compared with younger groups. Motorcycle training class enrollment rates were higher in the intervention group, particularly among those taking a course for riders with intermediate skills (enrollment ratio = 2.24; 95% CI = 1.41-3.55). CONCLUSION: The intervention appeared to increase licensure, yet the licensure rate remained low among the intervention group. Potential risks and benefits of increasing the percentage of motorcyclists who are licensed need to be studied. 相似文献
482.
The Danish emergency response model of the atmosphere (DERMA) 总被引:1,自引:0,他引:1
483.
Nikitin AI Chumichev VB Valetova NK Katrich IY Kabanov AI Dunaev GE Shkuro VN Rodin VM Mironenko AN Kireeva EV 《Journal of environmental radioactivity》2007,96(1-3):138-143
Data on content of (90)Sr, (137)Cs, (239,240)Pu and (3)H in water of the Tobol-Irtysh part of the Techa-Iset-Tobol-Irtysh-Ob river system (through which the "Mayak" PA radioactive wastes are transported) are presented and discussed. The data were received in 2004-2005 under the ISTC project on radioecological monitoring of the Tobol and Irtysh rivers. Monthly observations of (137)Cs, (90)Sr and (3)H content in water in the area of the Tobol and Irtysh confluence have been conducted starting from May 2004. To obtain information on the investigated river system as a whole, the radioecological survey of the Tobol and Irtysh rivers at the section from the mouth of the Iset River to the confluence with the Ob River was carried out in 2004. It is shown that the impact of "Mayak" PA waste transport by (90)Sr is distinctly traced as far as the area of the Irtysh and Ob confluence. 相似文献
484.
David Alexander JC Gaillard Ilan Kelman Fausto Marincioni Edmund Penning‐Rowsell Dewald van Niekerk Lauren J. Vinnell 《Disasters》2021,45(1):5-18
Nowadays there are approximately 80 Anglophone journals that deal primarily with disaster risk reduction (DRR) and allied fields. This large array signals a sustained, if uneven, growth in DRR scholarship but also competition between the offerings of different publishers and institutions. The purpose of this article is first to summarise the development of academic publishing on DRR from its early beginnings to the present day. The paper then evaluates the current state of publishing in this field and discusses possible future trends. Next, it identifies some possible opportunities, challenges, expectations, and commitments for journal editors both within DRR and academia more broadly, including those that refer to changes in the use of terminology, the relentless increase in the number of papers submitted, the expansion and dangers of predatory journals, different peer review models, open access versus paywalls, citations and bibliography metrics, academic social networks, and copyright and distribution issues. 相似文献
485.
Melissa S. Gerald James Ayala Angelina Ruíz-Lambides Corri Waitt Alexander Weiss 《Die Naturwissenschaften》2010,97(1):89-96
Several primate species show sexual dichromatism with males displaying conspicuous coloration of the pelage or skin. Studies
of scrotal coloration in male vervet monkeys (Chlorocebus aethiops) suggest that it is an important intrasexual signal, with relatively dark, colourful males dominating paler males. To date,
no studies have examined the influence of male colour on intersexual social interactions in vervet monkeys. The primary goal
of the present study was to evaluate whether female vervet monkeys attend to male coloration. We experimentally introduced
females, housed with either “pale” or “dark” males, to stimulus males whose scrota were pale, dark, or pale but painted to
look dark. Overall, during introductions, females did not differ in time spent directing affiliative behaviour toward pale,
dark, and painted males; however, females, permanently housed with dark males, spent significantly more time directing affiliative
behaviour toward pale than painted males. When the stimulus male was pale, affiliative exchanges between males and females
were longer than when the stimulus male was painted. Home male colour was not related to female-initiated aggression. Home
male colour was also not related to male-initiated aggression, although painted stimulus males were more likely to initiate
aggression than pale stimulus males. These findings lead us to conclude that females pay attention to male coloration, but
do not bias their interactions toward males solely on the basis of natural male coloration. 相似文献
486.
Turanoceratops tardabilis from the Upper Cretaceous (Turonian) Bissekty Formation of Dzharakuduk, Uzbekistan, represents the first definite ceratopsid
dinosaur recorded from Asia. Reexamination of the original and study of newly collected material indicate that Turanoceratops has well-developed supraorbital horns and apparently lacks a nasal horn. Turanoceratops is more derived than the more or less coeval Zuniceratops from the Moreno Hill Formation of New Mexico in the presence of double-rooted teeth and of two or three teeth in each vertical
dental file. 相似文献
487.
Karl-Werner Schramm Petra Marth Alexander Wolf Klaus Hahn Konstantin Oxynos Johannes Schmitzer Antonius Kettrup 《Environmental Sciences Europe》1999,11(5):277-280
Measured partition coefficients (KLM/L) related to lipid-concentrations between the muscle (CML) and liver (CLL) tissue of two fish species (Abramis brama, Zoarces viviparus) exhibit nominal values of unity according the relationship KLM/L=CML/CLL=1 for persistent compounds such as highly chlorinated PCB and values above one for degradable compounds for example chlorinated cyclohexanes or DDT. The corresponding theory is presented. The relationship holds for samples for single fish as well as for pooled samples. 相似文献
488.
Aline S. Turque Alexander M. Cardoso Cynthia B. Silveira Ricardo P. Vieira Flávia A. D. Freitas Rodolpho M. Albano Alessandra M. Gonzalez Rodolfo Paranhos Guilherme Muricy Orlando B. Martins 《Marine Biology》2008,155(2):135-146
In this study we performed a survey of the bacterial communities associated with the Western Atlantic demosponges Hymeniacidon heliophila and Polymastia janeirensis, based on 16S rRNA sequencing and transmission electron microscopy (TEM). We compared diversity and composition of the sponge-associated
bacteria to those of environmental bacteria, represented by free-living bacterioplankton and by bacteria attached to organic
particulate matter in superficial sediments. Partial bacterial 16S rRNA sequences from seawater, sediment, and sponges were
retrieved by PCR, cloning, and sequencing. Sequences were subjected to rarefaction analyses, phylogenetic tree construction,
and LIBSHUFF quantitative statistics to verify coverage and similarity between libraries. Community structure of the free-living
bacterioplankton was phylogenetically different from that of the sponge-associated bacterial assemblages. On the other hand,
some sediment-attached bacteria were also found in the sponge bacterial community, indicating that sponges may incorporate
bacteria together with sediment particles. Rare and few prokaryotic morphotypes were found in TEM analyses of sponge mesohyl
matrix of both species. Molecular data indicate that bacterial richness and diversity decreases from bacterioplankton, to
particulate organic sediment, and to H. heliophila and P. janeirensis. Sponges from Rio de Janeiro harbor a pool of novel and exclusive sponge-associated bacterial taxa. Sponge-associated bacterial
communities are composed of both taxons shared by many sponge groups and by species-specific bacteria. 相似文献
489.
Symbiotic bacteria from six Oscarella species (adults and embryos) collected in the Mediterranean Sea (O. lobularis, O. tuberculata, O. imperialis, O. microlobata, O. viridis) and the Sea of Japan (O. malakhovi) were investigated by scanning electron microscopy and transmission electron microscopy. In most cases, symbionts are rather
numerous. Each sponge species has a definite set of bacterial morphological types. All bacteria are extracellular. Symbionts
occupy the mesohyl of adult sponges or intercellular space in embryos and are often in contact with mesohylar filaments or
cells. Bacteria of some morphotypes have characteristic blebs. Most symbionts are gram-negative, and two types of bacteria
have traits of Archaea and one type of bacteria is similar to Planctomycetes. Data on morphology of bacterial symbionts can
be a good additional character for identification of Oscarella species, which have no skeleton. 相似文献
490.
Ximena E. Bernal Karin L. Akre Alexander T. Baugh A. Stanley Rand Michael J. Ryan 《Behavioral ecology and sociobiology》2009,63(9):1269-1279
We investigated the natural dynamics in a sexual signal that combines different call components and explored the role of call
complexity in sexual selection using a neotropical frog. Male túngara frogs, Physalaemus pustulosus, facultatively add up to seven short, multi-harmonic components (chucks) to the simple form of their calls (whines). Female
túngara frogs are preferentially attracted to whines with chucks over whines without chucks, and males also call more in response
to calls containing chucks. Because acoustic predators prefer complex calls, in the context of simple (no chucks) versus complex
(any number of chucks) calls, the variably complex call appears to have evolved in response to the opposing selective forces
of natural and sexual selection. There is no evidence, however, for the function of increasing the number of chucks within
complex calls. We tested two aspects of increasing call complexity: natural patterns of use of call types in males and how
both sexes respond to variation in multi-chuck calls. Males incrementally change call complexity by the addition or subtraction
of a single chuck and usually do not produce more than two chucks. Variation in call complexity, for calls with at least one
chuck, does not influence response calling in males or phonotaxis in females. Our results suggest that one reason for not
increasing call complexity beyond a single chuck is the diminishing effectiveness on the responses of both sexes.
This is a posthumous publication for A. Stanley Rand 相似文献