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521.
Familial dysautonomia (FD), a recessively inherited disease, has been mapped to chromosome 9q31. Highly polymorphic dinucleotide repeat markers flanking the genetic locus and at the same genetic location have been identified. We describe the prenatal diagnosis of FD using linkage and linkage disequilibrium analyses with these markers. Twelve families were analysed for informativeness and of these, seven went on to have prenatal testing (a total of eight fetuses tested). All of these fetuses were predicted to be heterozygous unaffected (FD carriers). Seven fetuses have come to term and are normal. In the absence of a recombinant proband, a panel of three proximal and three distal markers is sufficient to provide informative flanking markers and an 87–96 per cent likelihood of a highly predictive test. In an additional family at 1:4 risk for FD, no DNA was available from the propositus. This family was analysed using linkage disequilibrium to the #18 allele of the tightly linked marker D9S58 in conjunction with linkage analysis using data from two unaffected children. Prenatal diagnosis in this family indicated an affected fetus.  相似文献   
522.
The evaluation of microbial responses to three in situ source removal remedial technologies—permanganate‐based in situ chemical oxidation (ISCO), six‐phase heating (SPH), and steam injection (SI)—was performed at Cape Canaveral Air Station in Florida. The investigation stemmed from concerns that treatment processes could have a variety of effects on the indigenous biological activity, including reduced biodegradation rates and a long‐term disruption of community structure with respect to the stimulation of TCE (trichloroethylene) degraders. The investigation focused on the quantity of phospholipid fatty acids (PLFAs) and its distribution to determine the immediate effect of each remedial technology on microbial abundance and community structure, and to establish how rapidly the microbial communities recovered. Comprehensive spatial and temporal PLFA screening data suggested that the technology applications did not significantly alter the site's microbial community structure. The ISCO was the only technology found to stimulate microbial abundance; however, the biomass returned to predemonstration values shortly after treatment ended. In general, no significant change in the microbial community composition was observed in the SPH or SI treatment areas, and even small changes returned to near initial conditions after the demonstrations. © 2004 Wiley Periodicals, Inc.  相似文献   
523.
Building commitment and preventing costly turnover of technical employees are key challenges facing organizations today. We examine whether the elements of the employment relationship that predict commitment and willingness to change companies vary significantly with age. Using a sample of over 3000 technical professionals from six large companies, we find that in comparison to those under 30, satisfaction with job security is more strongly related to the commitment of more senior workers (ages 31–45 and those over age 45) and to their desire to remain with their companies. In contrast, satisfaction with work–life balance is more strongly related to commitment of those under age 30 than those over 30. Also, for the under‐30s, satisfaction with opportunities to develop technical skills and pay linked to individual performance has a stronger negative relationship with willingness to change companies than for those over 45. While statistically significant, the size of the age effects is small, suggesting popular and managerial attention devoted to differences among age groups may be overblown. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
524.
This paper examines individuals' theories about cue use in organizations — theories about which of the many cues available in an organization's feedback environment they should use to guide their behavior. It also investigates how these theories vary with increasing organizational experience. The research assesses individual's implicit theories regarding cue use using both open- and closed-ended data collection methods. Results suggest that, regardless of experience, individuals place the most importance on cues from the company and their supervisors. Peer feedback and self-observations were seen as much less important. These results are interesting in light of previous studies showing that the self was the most available, and the organization the least available, source of feedback. With experience, managers appear to learn to emphasize negative over positive feedback, especially from superiors, and to emphasize their peers' actions over their words when a negative message is being conveyed.  相似文献   
525.
Existing federal and state environmental regulatory structures divide the world into three mutually exclusive “media”: air, water, and land. Many experts believe that both pollution prevention and technological innovation would benefit from an integrated, multimedia permitting process. This article profiles groundbreaking programs in the two states that have taken the lead in multimedia permitting—New Jersey and Massachusetts.  相似文献   
526.
ABSTRACT: Water hyacinth (Eichhornia crassipes L.) has shown to be effective in the treatment of municipal wastewater in a pilot study begun in January 1989 by the Pima County Wastewater Management Department and researchers associated with The University of Arizona's Office of Arid Lands Studies in the Sonoran Desert near Tucson. The influent pumped into the pilot facility's six raceways (ponds) typically has been treated secondary effluent diverted from a conventional treatment facility, although primary effluent from the same facility also has been treated. The Secondary Influent Treatment System has met the Arizona Department of Environmental Quality (ADEQ) tertiary standard for BOD5 and TSS of 10 mg/l for every month of its operation since March 1990; the Primary Influent Treatment System met the ADEQ secondary standard for BOD5 and TSS of 30 mg/1 for most of the 10 months it was in operation.  相似文献   
527.
A tour guide training program was developed for rural communities near Costa Rica's Tortuguero National Park to respond to the impacts of the 24-fold increase in park visitation in the past decade, to involve local communities in resource management, and to provide regional environmental education. The development of the training course involved a survey of scientists and park managers to ascertain resource management needs, priorities for information to be disseminated, and impacts of tourism on the resource base. Current and potential tour guides were surveyed to identify their information needs, solicit their input in the training program, and to determine their knowledge and skills. Written questionnaires were developed and given to 400 tourists to determine their activities and environmental information needs, and hotel owners were censused to examine the economic feasibility of a local guide program. A pilot training course and guide program involving 12 Tortuguero residents demonstrated that a tour guide program: (1) helped mitigate negative tourism impacts on Tortuguero National Park's natural resources, particularly by regulating tourists on the park's 35-km beach used for nesting by endangered sea turtles; (2) provided environmental education to an important segment of the local community not traditionally reached through school or government development projects; (3) provided environmental information to tourists, thus enhancing their visit; and (4) provided local economic benefits through lucrative part-time employment, thereby allowing local people to participate more fully in the tourism system. An extended training course is being planned to provide further environmental education programming and to increase year-round employment opportunities for the tour guides.  相似文献   
528.
529.
ABSTRACT: Artificial substrates were designed using rock filled polyethylene bags which were perforated with holes. The substrates trapped waterborne sediment and detritus which enhanced microhabitat complexity. Colonization was compared in side-by-side tests with multiple plate samplers in mountain streams ranging from second to seventh order. After 41 days the bag samples contained more sediment and detritus and more animals than did multiple plates. Plastic bags exceeded multiple plate samples by a factor of nearly 8 for individuals and 1.5 for taxa expressed as numbers/sampler. Although detritus amounts differed significantly between samplers, catch composition was similar in habitat preference and functional groups. Most taxa were “lotic erosional” or “lotic erosional-depositional” detritivores. The plastic bags better represented the streambed fauna judged by their greater similarity to dip net samples. Bag samplers had 4.5 × the colonization area of multiple plates, hence would be expected to support more species. Catch/m2 of colonization area was not significantly different between samplers. Functionally the plastic bags act as detritus retention devices, offering a diverse, highly dynamic microhabitat for colonization. Results are interpretable in terms of research on microdistribution of stream benthos and the river continuum model. This study supports the conclusion that stream benthos abundance and diversity are related to the amount of detritus. Maximum diversity and numbers of individuals occurred in samples from third and fourth order streams. Grazers reached peak abundances in the same streams where the continuum model predicts P>R Shredders reached maximum abundances in third and fourth order streams where the riparian canopy was greatest. Predator abundance changed little with stream size. Although bag samples required more sorting time, the samplers are catch effective, inexpensive, and adaptable.  相似文献   
530.
A quasi-experiment was used to compare employee behaviors before and after stress management training. Organizational records on employee absenteeism, performance ratings, equipment accidents, and work injuries were obtained for highway maintenance workers who received biofeedback (BIO=21) or muscle relaxation (MR=16) training. Similar data were gathered for a comparison group of employees who did not volunteer for training (n = 80). The pre-training period (time 1) consisted of 2 1/2 years. The post-training period was divided into the year immediately after training (time 2) and the following 1/2 year (time 3). Multiple regression analyses indicated that the MR (but not BIO) group variable explained unique variance in time 2 absenteeism (p < 0.05) but not in performance ratings, equipment accidents, nor work injuries (p > 0.05). Neither group entered predictive models for any measure at time 3 (p > 0.05). The results provide limited support for relaxation training offered as a prevention activity in work settings.  相似文献   
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