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61.
Prenatal diagnosis for infantile osteopetrosis was attempted during the third pregnancy of a first-cousin marriage whose family history revealed an affected previous child. At the 25th week of pregnancy, fetal X-ray evaluation revealed marked sclerosis of osteopetrotic bone and metaphyseal splaying and clubbing of both femurs. The pregnancy was terminated and repeated X-rays and histopathological examination of fetal bone (femur) confirmed the diagnosis.  相似文献   
62.
In the fifteen-spined stickleback (Spinachia spinachia), the male alone builds a nest and provides care for the eggs until they hatch. The nest is made of filamentous algae held together with shiny secretional threads of a glycoprotein, here called tangspiggin. Tangspiggin is produced by transformed kidney cells. I investigated how tangspiggin production was related to food intake by giving males low or high food rations. Males in the high-food group produced significantly more tangspiggin than those in the low-food group. Since low food rations did not lead to a significant drop in resting metabolic rate (oxygen consumption), tangspiggin production appears to be one of the first energy-demanding processes to be dropped during food deprivation. Among males given equal food rations, females preferred to mate with those with elevated levels of tangspiggin in their nests. Tangspiggin threads may signal safety for the offspring by keeping the eggs within the nest and protecting them from egg predators. Moreover, the threads become less shiny with age, due to particle deposition, and older nests that may house older (more valuable) eggs are thereby well camouflaged. Tangspiggin provides an honest signal of male condition, acting as an extra-bodily ornament, signaling direct benefits to females or possibly also indirect benefits of "good genes" from a male who is a successful forager.  相似文献   
63.
There is a genetic component to plasticity in age polyethism in honey bee colonies, such that workers of some genotypes become precocious foragers more readily than do workers of other genotypes, in colonies lacking older bees. Using colonies composed of workers from two identifiable genotype groups, we determined that intracolony differences in the likelihood of becoming a precocious forager are a consequence of differences in rates of behavioral development that are also evident under conditions leading to normal development. An alternative hypothesis, that differences in the likelihood of becoming a precocious forager are due to differences in general sensitivity to altered colony conditions, was not supported. In three out of three trials, workers from the genotype group that was more likely to exhibit precocious foraging in single cohort colonies also foraged at relatively younger ages in colonies in which workers exhibited normal behavioral development. In contrast, in three out of three trials, workers from the genotype group that was more likely to exhibit precocious foraging in single-cohort colonies did not show disproportionately more overaged nursing in colonies in which workers exhibited delayed development. These results indicate that genotypic differences in plasticity in age-related division of labor are based on genotypic differences in rates of behavioral development.  相似文献   
64.
Food and Environmental Virology - Norovirus is commonly associated with food and waterborne outbreaks. Genetic susceptibility to norovirus is largely dependent on presence of histo-blood group...  相似文献   
65.

The present study describes the application of different solid-phase extraction techniques for the extraction, separation, and quantitative determination of 10 commonly used herbicides with different chemical structures (chlorsulfuron, diuron, bentazone, linuron, chlorpropham, fenoxoprop-ethyl, MCPA, diclofop-methyl, fluazifop-butyl, trifluraline) in water. Octadecyl (C18) Empore extraction disks, octadecyl (C18), and stryene divinylbenzene (SDB) Bond Elut Env cartridges were compared for solid-phase extraction efficiency. Herbicides were separated and quantified by reversed-phase high performance liquid chromatography with diode-array detection (HPLC-DAD) with simultaneous separation on two columns of differing polarity (C18 and CN) to confirm identification. Analytical separation was performed simultaneously on C18 and CN columns. Reanalysis of the sample extracts on a (cyano) CN column were used to confirm the identity of these compounds. Method optimization and validation parameters were presented in this work. Recoveries varied from 76.0% to 99.0% for C18 disks, from 75.1% to 100.0% for C18 cartridges, and from 54.0% to 98.0% for SDB cartridges over concentrations at 0.025–0.4 μg L?1. The limits of detection were 0.012–0.035 μg L?1.  相似文献   
66.
67.
The most important tool for testing seat-systems in rear impacts is a crash test dummy. However, investigators have noted limitations of the most commonly used dummy, the Hybrid III. The BioRID I is a step closer to a biofidelic crash test dummy, but it is not user-friendly and the straightening of the thoracic spine kyphosis is smaller than that 220of humans. To reduce these problems, a new BioRID prototype was developed, the P3. It has new neck muscle substitutes, a softer thoracic spine and a softer rubber torso than does the BioRID I.

The BioRID P3 was compared with volunteer test data in a rigid and a standard seal without head restraints. The dummy kinematic performance, pressure distribution between subject and seatback, neck loads and accelerations were compared with those of ten volunteers and a Hybrid III. The BioRID P3 provided repeatable test results and its response was very similar to that of the average volunteer in rear impacts at Δv = 9 km/h.  相似文献   
68.
Hatchling sex ratios in the loggerhead turtle (Caretta caretta) were estimated by placing electronic temperature recorders in 21 nests at Fethiye beach during 2000–2002. Over the seasons, the mean temperature in the middle third of the incubation period ranged from 26.7 to 32.1°C, and incubation periods ranged from 49 to 67 days. Based on the mean temperatures during the middle third of the incubation period, and on histologically sexed dead hatchlings, the sex ratios of hatchlings at Fethiye beach were roughly equal, i.e. 60–65% of the hatchlings were females. This contrasts with the highly female-skewed sex ratios in loggerhead turtles elsewhere; Fethiye has a relatively high proportion of male hatchlings. For endangered sea turtles, the knowledge of hatchling sex ratios at different beaches, coupled with appropriate conservation measures, can make an important contribution to their survival.  相似文献   
69.
Wastewater treatment sludge contains valuable nutrients, yet represents a residue problem due to the amount of heavy metals, which is one of the factors preventing the use of sludge as fertilizer. In Sweden, the government has a declared aim of closing the ecocycles of nutrients to arable land, while at the same time the existing limit values are among the lowest in the world. This paper focuses on the opportunities for Swedish wastewater utilities (WWUs) to manage and reduce sources of heavy metals in order to get sludge approved and recycled. A case study focusing on sources of the heavy metals Cd, Cu, Hg, Ni, Pb, and Zn and the WWUs ability to influence the source by means of existing regulations was traced and categorized. A substantial fraction of the heavy metals were shown to be caused by diffuse emissions, such as the use of goods and products in society. For most sources discussed in the paper, a WWU can only manage the sources to a limited extent, if at all. This study shows that the WWUs cannot manage both recycling of nutrients and a decrease in heavy metals ending up in sludge. Diffuse emissions of heavy metals must be examined in context, not as a separate phenomenon or an issue for a single actor. The existing environmental legislation does not handle diffuse sources, yet long-term strategies for reducing the emissions to wastewater treatment must involve the reduction of diffuse emissions.  相似文献   
70.
Nose-level measurements of air toxics were made along a busy urban street in Ottawa, Canada for 2 hr periods during morning, noon, and afternoon rush hours in the winter and summer of 2000. Measurements were also made in a commuter car and a transit bus during morning and afternoon commutes in 2000. The main objectives of the study were to establish a database, to determine temporal and seasonal variations and to determine the contribution of motor vehicle traffic to the measured toxic substance concentrations. Ottawa is an appropriate choice of location for the measurement of motor vehicle related toxic and reactive compounds, as it has virtually no industrial sources that could be contributing to the ambient loadings. Samples were collected for a total of 165 volatile organic compounds and 25 carbonyl compounds. Sampling and analytical methodologyare discussed and results are presented. Toluene, ethylene andformaldehyde were the most abundant pollutants in Ottawa during both winter and summer. Total non-methane hydrocarbon concentrationwas measured as 100 g m-3 at nose-level measurements in Ottawa.  相似文献   
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