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101.
IntroductionThe aims of this study are: (a) to estimate the prevalence of passengers riding with alcohol-impaired drivers; (b) to investigate the role of demographic factors (age, gender, race/ethnicity, educational status) and relevant driving conditions (time of the day, trip origin, vehicle ownership) on shaping the likelihood of alcohol-impaired driving; (c) to identify and estimate the prevalence of passengers as alternative drivers (PADs); and (d) to examine the role that vehicle ownership plays in shaping the occurrence of PADs.MethodData came from a unique convenience sample of passengers obtained from the 2007 National Roadside Survey, a random sample of drivers from the 48 contiguous states.ResultsThe prevalence of PADs in the targeted population (mostly weekend night vehicles) was higher with drivers at .00 < BAC < .08 (17%-43%) than at BAC ≥ .08 (6%-29%) drivers. The evidence suggests that targeted policies to encourage PADs to drive might be possible. However, vehicle ownership is a large impediment for PADs to act as designated drivers. We speculate that vehicle ownership may be a main reason for the less-than expected success of the “designated driver” concept. 相似文献
102.
Paola Di Leo Massimo Bavusi Giuseppe Corrado Maria Danese Tonia Giammatteo Dario Gioia Marcello Schiattarella 《Journal of Coastal Conservation》2018,22(5):865-877
In the ancient territory of the Greek settlement of Metaponto and its Chora (Ionian sector of Basilicata, southern Italy) geomorphological mapping, GIS-supported statistics, and landform topographic features were investigated and combined to extract settlement rules and site dynamics. Analyses of environmental dynamics as well as of spatial and temporal settlement evolution were carried through an integrated approach that, starting from a detailed geomorphological analysis, tried to extract the spatial relationships between archaeological site locations and landform/landscape features. Spatial analysis was used to investigate the relationships between environmental parameters and archaeological sites. The advantages to develop a predictive model using Archeological Spatial Evaluation (ASE) analysis lay in the possibility to deeply study the relationships between man and the environment. In the present study, the analysis was carried out in a pioneering way in the ~400 km2 Metaponto territory in order to robustly validate - in the aftermath data - human and territorial dynamics. A model describing interactions between sites and parameters such as elevation, slope, aspect, landforms, land use, and distances from rivers was constructed. Sensibility maps were produced, which will help archaeologists to know how many and which are the parameters increasing the probability to find new archaeological sites as well as how the main geomorphological features of the study area, contextualized within the most likely paleoclimate scenario, affect ancient site arrangement though time. The preferential occupation of mid-altitude marine terraces, and the consequence spreading of agriculture on these territories, is likely due to the existence of well-developed soil profiles on them. Clearly colonists recognized that on these landform units there were the better conditions for the development of massive agricultural practices: since the SP age (4,1 to 2,0 Kyr B.P.) the settlers expands inland looking for most fertile territories as well as for areas sufficiently protected (being far away from the coast). The increase in farmhouses on the top of marine terraces from the FC up to EC-EE periods and the modifications of settlement distribution (gradual abandonment of alluvial) in the Metaponto area is likely related to the acceleration of alluvial processes. The progressive decrease of human occupation during the Hellenistic up to the Roman Age is clearly consequence of the Roman conquest. However, a role played by the increase in flooding occurrence in the coastal plain/floodplains of the main rivers in triggering the abandonment of these territories and marking the beginning of the decadent phases should not be neglected. Productive areas (locally associated to farmhouses) are preferential set along the fluvial incisions (sometime associated to farmhouses), thus implying that productive area setting is strongly linked to the presence of rivers, and of their lower rank tributaries, both as an intrinsic need of manufacturing and to facilitate the spreading of products. From the Classical to the Hellenistic Age until the Roman Age, Necropolis are spread in the entire area, from marine terraces to alluvial plain. On the other hand, Sacred areas - which appearance is recorded starting from the Colony Foundation Age - exhibits a settlement continuity in the study area starting from this time up to the entire Roman period, and the sacred areas setting is strictly associated to the category of Settlement. 相似文献
103.
Andrea Bonisoli-Alquati Diego Rubolini Maria Romano Marco Cucco Mauro Fasola Manuela Caprioli Nicola Saino 《Behavioral ecology and sociobiology》2010,64(5):845-855
Maternal effects through albumen quality are largely unexplored, despite the fundamental role that albumen exerts as source
of proteins and water, as well as for antimicrobial defence of the embryo. We analysed the variation of two major albumen
antimicrobials, avidin and lysozyme, by extracting samples from freshly laid eggs of the yellow-legged gull (Larus michahellis) and by correlating their levels to egg features. Lysozyme concentration increased along the laying sequence, while avidin
concentration decreased. Both antimicrobials declined during the season. In addition, avidin concentration declined from first-
to last-laid male eggs, whereas the opposite was true among the female eggs. We also analysed chick body mass and size and
immune response, in relation to albumen antimicrobial levels in their original egg while controlling for potential covariation
between egg quality and rearing conditions by cross-fostering eggs between nests. Tarsus length decreased with avidin concentration,
particularly early in the season. Avidin concentration negatively predicted tarsus length of chicks and the phytohaemagglutinin
response of females, but not males. However, chick phenotype did not covary with lysozyme albumen concentration. This is the
first study where maternal effects mediated by albumen antimicrobials are investigated in relation to both sex and egg features
in any wild bird species. Whether the observed patterns of variation in antimicrobial concentration are the by-product of
maternal physiological constraints, or reflect adaptive allocation strategies, cannot be ascertained. The covariation between
chick cell-mediated immunity and albumen avidin concentration might be causal, according to the documented effects of albumen
proteins on immunity in other species. 相似文献
104.
Nicola Saino Maria Romano Diego Rubolini Manuela Caprioli Roberto Ambrosini Mauro Fasola 《Behavioral ecology and sociobiology》2010,64(11):1813-1821
Parental decisions can determine offspring experience of environmental conditions. Such ‘maternal’ effects act both before and after hatching via, e.g., egg quality or the social milieu predisposed by parents. Resource availability may constrain the expression of adaptive maternal effects, and the specific pattern of allocation of these effects among offspring depending on their sex or birth order can result in different fitness payoffs to parents. Declining egg mass with laying order observed in several bird species may constitute an adaptive strategy of parental favouritism towards early hatching offspring with larger reproductive value but may also result from nutritional constraints on laying effort. A previous study has shown that the small size of the third, last laid (c-)egg in yellow-legged gull (Larus michahellis) clutches depends on food availability and that food-supplemented mothers increase the size of their female but not male c-eggs. Here, we show that increased mass of c-eggs laid by females supplemented with food after clutch initiation depends on increased albumen mass, which, in turn, enhances the size of daughters at hatching. Because asynchronous hatching results in a competitive disadvantage of c-chicks, present results suggest that mothers relieved from nutritional constraints enhance the size of daughters to compensate for their larger susceptibility to hatching last. The study also confirms the role of egg albumen content in determining hatchling size, previously experimentally detected only in one species in the wild. The effect of increased egg mass on offspring size persisted at least until day 8 after hatching, when, however, it did not vary with sex, suggesting intense negative selection on small female c-chicks in control broods. Hence, maternal effects mediated by egg albumen content had persistent effects on offspring size. 相似文献
105.
Energy charge (EC) ratios of microplankton samples have been measured from their adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) contents, according to a method based on enzymatic tranformations of ADP and AMP into ATP, and the subsequent quantitative analysis of the latter by the bioluminescent reaction of a firefly lantern extract (Photinus pyralis). Interference caused by other non-adenylic nucleotides and bioluminescence inhibition by various compounds were reduced, or estimated, by the use of internal standards for each sample. This was accomplished both by the injection of a small volume of a non-commercial extract of P. pyralis and by measurement of the bioluminescent flash at its maximal value. This standard method for preparation and analysis afforded good reproducibility and permitted the calibration of individual samples, thus allowing the comparison and treatment of data in the large series necessary in oceanographic studies. Studies were made on natural populations taken from a polluted marine area where phytoplankton communities live under the stressful influence of an urban sewer outlet, near Marseille (France). Three sampling strategies in surface waters (transects from the outlet, sampling during a 24-h buoydrift, and regular sampling for a day-night period) conducted at a point in front of the outlet revealed a decrease of EC in relation to urban activity or approaching proximity of the sewer outlet. These low EC values (0.2 to 0.5) were caused by a high AMP content, perhaps originating from degraded biogenic particles and dead or metabolically impeded bacteria of terrestrial orgin stressed by ecologic factors such as increased salinity and decreased temperature. Further away from the sewage outlet, the EC increased as the bacterial population decreased, and the phytoplanktonic communities reappeared parallel to the dilution of the effluent. Although in mature and unperturbed ecosystems EC values of 0.70 to 0.80 were recorded, the values were generally lower than those measured in growing bacterial or phytoplankton cultures. This fact may be related to differences in the various metabolic states of multispecific populations. Some EC measurements from deeper microplankton samples presented in this paper were difficult to interpret, reflecting perhaps unsolved problems concerning the treatment of samples. However, it was possible to associate the range of variation in EC values to differences in composition and structure of the ecosystem of microplankton populations in neritic surface waters. 相似文献
106.
The influence of the sewage from the city of Marseilles, France, upon the marine microplanktonic assemblages was followed over a period of one year (May 1980–April 1981) at five stations and three sampling depths. Measurements of the 14C assimilation rate, adenylate energy charge, and the electron-transport system (ETS) were compared with parallel phytoplankton and bacteria counts. In the coastal waters near the sewage outlet the phytoplanktonic organisms were stressed, as attested by the low values of both assimilation rate and energy-charge ratios; the living microbiomass in these waters was essentially of bacterial origin. In waters situated 4 to 5 km away from the outlet, and therefore not directly under its influence, higher mean P:B and EC ratios indicated the presence of a predominantly living phytoplanktonic assemblage. Nevertheless, the metabolic stress induced by the inflow of polluted water to the waters near the sewage outlet did not prevent the occurrence of a spring bloom. The electron-transport system measurements and their relationship to the effective bacterial counts are in good accordance with the literature data describing laboratory cultures, and indicate intense heterotrophic activity in the waters nearest to the sewage outlet. This activity is most probably of bacterial origin: perhaps some of the terrestrial germs introduced into the marine environment remained viable, perhaps the considerable volume of organic matter introduced into this area induced heterotrophic development, or perhaps both factors combined. Simultaneous consideration of biochemical and physiological data with the structure and composition of the microplanktonic populations could explain the apparent contradiction between the high level of nutrient supply and the lack of photoautotrophic growth noted in previous studies in this area. However, the considerable amounts of fresh organic matter present in the waters near the sewage outlet at Cortiou indicate the necessity for great care in the use of biochemical parameters such as chlorophyll or AMP for the estimation of microplankton biomass; such estimates can be biased by the presence of non-degraded detrital particles of biological origin. 相似文献
107.
Bivalves demonstrate various morphological and behavioural adaptations to reduce the risk of being attacked by predators.
This paper examines how the presence of the crab Carcinus maenas (L.), a natural predator of the cockle Cerastoderma edule (L.), affects its burrowing depth and clearance or feeding rate. Cockles were placed in experimental tanks and treated with
three levels of predatory disturbance: (1) unfed crab loose inside the tank, (2) unfed crab inside a cage suspended in the
water column and (3) no crab present. Cockles’ burrowing depth was measured in two sediment types: mud and sand. Cockles burrowed
more deeply in treatments with no crabs. Burrowing depth in sand was significantly greater than in mud. Two factors may contribute
to the reduction in burial depth of C. edule in the presence of C. maenas: the change in the vertical orientation of the cockle and the ‘cough response’. No significant difference was found in the
cockles’ clearance rate among the different levels of predator threat. 相似文献
108.
Flavia D’Agostin Corrado Negro 《International journal of occupational safety and ergonomics》2013,19(2):274-284
Background. Most studies have shown that nurses have a higher risk of developing musculoskeletal symptoms compared with other occupational groups. Aim. A cross-sectional study was performed to gain more insight into the prevalence rates of musculoskeletal disorders (MSDs) in nurses. Methods. The presence of musculoskeletal symptoms was revealed by personal interviews in a sample of 177 hospital nurses and in a reference group of 185 university employees. Musculoskeletal diseases were based on radiological examinations in all subjects. Results. Lower back pain (61% vs 42.2%) was the most frequently reported symptom, followed by neck pain (48.6% vs 38.4%) and shoulder pain (36.7% vs 25.9%), with a significantly higher prevalence in nurses. Women had about a 2-fold risk of upper limb region and neck pain compared with men. The most common abnormal findings on radiological examinations were disc herniations (n?=?40). Conclusions. Nurses showed a significantly higher risk of MSDs. Prevalence rates in nurses increased significantly with age. Musculoskeletal symptoms were also common in university employees. This suggests the need for effective intervention strategies involving workers’ active participation, in order to improve the process and organization of work and promote a positive psychosocial work environment. 相似文献
109.
Togliatti Elena Milanese Daniel Pugliese Diego Sciancalepore Corrado 《Journal of Polymers and the Environment》2022,30(9):3914-3933
Journal of Polymers and the Environment - In this work new biodegradable composite materials based on poly(butylene-adipate-co-terephthalate) (PBAT) reinforced with water-soluble calcium-phosphate... 相似文献
110.