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321.
Water and air quality of eight seawater swimming pools using chlorine disinfection was measured during four sampling campaigns, spread on one full-year, and in four thalassotherapy centers located in Southeast of France. Concentrations of trihalomethanes(THMs) in air and in water as well as concentrations of parameters, including nonpurgeable organic carbon(NPOC), free residual chlorine(Cl_f), pH, Kjeldhal Nitrogen(KN), salinity,conductivity, bromide ions and, water and air temperature, were measured. Water and air samples were collected in triplicates morning — at the opening of the pools —, noon and night — at the closing of the pools —, in summer and winter. Data analysis was performed by Principal Component Analysis(PCA) and rotated component matrix, from both data quality and other parameters such as TOC, aromaticity(UV_(254)), pH, hygrometry, and free residual chlorine(Cl_f). This statistical analysis demonstrates a high correlation between TOC, Cl_fand UV_(254) and THM levels found in air and water, particularly for the major ones(CHBr_3in water:300.0 μg/L mean, 1029.0 μg/L maximum; CHBr_3 in air: 266.1 μg/m~3 mean,1600.0 μg/m~3 maximum, and CHClBr_2 in water: 18.9 μg/L mean, 81.0 μg/L maximum;CHClBr_2 in air: 13.6 μg/m~3 mean, 150.0 μg/m~3maximum). These high levels of bromoform(CHBr_3) are particularly worrisome in such health institutions, even these levels do not exceed the Permissible Exposure Limit(PEL) of 5 mg/m~3 as an 8 hour time-weighted average currently fixed by various administrations, such as Occupational Safety and Health Administration(OSHA).  相似文献   
322.
Working along forest edges, we aimed to determine how some caterpillars can co-exist with territorially dominant arboreal ants (TDAAs) in tropical Africa. We recorded caterpillars from 22 lepidopteran species living in the presence of five TDAA species. Among the defoliator and/or nectarivorous caterpillars that live on tree foliage, the Pyralidae and Nymphalidae use their silk to protect themselves from ant attacks. The Notodontidae and lycaenid Polyommatinae and Theclinae live in direct contact with ants; the Theclinae even reward ants with abundant secretions from their Newcomer gland. Lichen feeders (lycaenid; Poritiinae), protected by long bristles, also live among ants. Some lycaenid Miletinae caterpillars feed on ant-attended membracids, including in the shelters where the ants attend them; Lachnocnema caterpillars use their forelegs to obtain trophallaxis from their host ants. Caterpillars from other species live inside weaver ant nests. Those of the genus Euliphyra (Miletinae) feed on ant prey and brood and can obtain trophallaxis, while those from an Eberidae species only prey on host ant eggs. Eublemma albifascia (Erebidae) caterpillars use their thoracic legs to obtain trophallaxis and trophic eggs from ants. Through transfer bioassays of last instars, we noted that herbivorous caterpillars living in contact with ants were always accepted by alien conspecific ants; this is likely due to an intrinsic appeasing odor. Yet, caterpillars living in ant shelters or ant nests probably acquire cues from their host colonies because they were considered aliens and killed. We conclude that co-evolution with ants occurred similarly in the Heterocera and Rhopalocera.  相似文献   
323.
Musculoskeletal pain is a common occupational hazard experienced by surgeons. Ear, nose and throat (ENT) surgeons are predisposed to neck and back pain due to regular prolonged microscopic work. We conducted a prospective pilot study to investigate the effects of sustained microscopic work on the neck and back, its correlation to surgical experience and to assess the benefits of a prototype postural support chair (PSC) amongst 10 male, ENT clinicians. We used a subjective measure of time to fatigue and pain for the neck and back as well as objective readings from a surface electromyogram (sEMG). We found that an increase in surgical experience correlated with the time taken to experience fatigue and pain in the neck and back. This was corroborated by our sEMG findings. The PSC significantly delayed the sensations in the neck and also eliminated the difference seen amongst the varying seniority of clinicians.  相似文献   
324.
Cyst-like masses in the neck and back region, simulating an encephalocele, were detected by midtrimester ultrasound examinations in two sib fetuses. After termination, the fetuses were found to have large cystic hygromas. The present observation strongly suggests the existence of an autosomal recessive type of cystic hygroma.  相似文献   
325.
A fetus with an extra idic(X) (q27) was ascertained during prenatal diagnosis. The derived X and one normal X chromosome were late replicating. Due to lack of previous experience, genetic counselling presented obvious difficulties and the fetal phenotype could be only tentatively predicted.  相似文献   
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Gnamptogenys menadensis is an arboreal nester that forages opportunistically almost exclusively on vegetation, sometimes recruiting others to participate in prey retrieval. The three-dimensional characteristics of vegetation suggest that functions describing recruitment decision thresholds or the pattern of recruitment in arboreal species may differ from those predicted by optimal foraging theory. To examine the effects of prey abundance and distance on the recruitment dynamics of G. menadensis, we baited nests with one termite, five termites or a number of termites between 20 and 40 either near to or far from the entrance and observed the ensuing behaviors. G. menadensis recruited others when encountering multiple termites regardless of the termite pile's distance from the nest, although a few individuals remained at the site and defended the resource. The pattern of arrivals at the site indicates that the majority and sometimes all arrivals were recruited from the branch trails. In combination, these results suggest that the architecture of the foraging habitat, which limits available return routes to the nest and thus increases encounter probabilities with potential recruits, shaped the process of information transfer and generated a collective pattern of foraging and prey retrieval.  相似文献   
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