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We describe the first prenatally detected case of a small de novo interstitial duplication of chromosome 16q. This chromosomal aberration is extremely rare. Amniocentesis was indicated by advanced maternal age only. Ultrasound examinations of the foetus showed no abnormalities. Conventional and molecular cytogenetic analyses on cultured amniocytes by comparative genomic hybridisation (CGH) and fluorescence in situ hybridisation (FISH) using partial chromosome paints and a locus-specific YAC clone revealed a de novo direct duplication of the chromosomal region 16q11.2-q13 leading to a partial trisomy 16q (46,XX,dup(16)(q11.2q13)). There are only five postnatal reports of comparable duplications involving this chromosomal region. These patients presented with little or no associated dysmorphic features but with significant neurodevelopmental delay and severe behavioural problems. After genetic counselling, the parents opted for termination of pregnancy. Post-mortem examination showed slight facial dysmorphic signs, minor dysgenesis of the ovaries and an atypical outflow of the arteria thyroidea ima. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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Objective: This study aimed to understand the awareness, riding behaviors, and legislative attitudes of electric bike (e-bike) users and non-e-bike road users toward e-bikes in Tianjin, a municipality in China.

Methods: This cross-sectional investigation included 2 components. The field survey was conducted in 9 districts (4 urban and 5 rural) from 2015 to 2017. Adult participants were interviewed using a street intercept method. The online survey was conducted using the WeChat social platform. A series of questions related to awareness and practice of e-bike safety-related issues was asked.

Results: A total of 16,859 interviews were completed, including 1,653 (794 e-bike users and 859 other road users) in-person interviews by field survey and 15,206 (4,426 e-bike users and 10,780 other road users) by online survey. Except for ignoring a red light when making a left turn (P?=?.000) and waiting across the white line at a red light (P?=?.000), which e-bike users were lower than other road users, there were no significant differences between e-bike users and other road users in regards to the correct awareness rate of riding in the opposite direction, riding in a motor vehicle lane, running red lights, jaywalking, speeding, carrying adult passengers, and riding on the expressway (P?>?.05). In addition, 74.2% of e-bike users considered helmet use necessary (P?=?.000) and 54.7% thought that installing a windshield is wrong (P?=?.000), which was higher than other road users (49.1 and 48.4%, respectively). Other road users had greater awareness than e-bike users regarding whether turning left at a red light is wrong (91.7 vs. 85.1%), waiting across the white line when the light is red is wrong (86.6 vs. 75.9%), lighs should be turned on at night (94.8 vs. 90.3%). Correct practices were far behind awareness in all kinds of violation behaviors (P?=?.000) among e-bike users in the field survey. The rate of public support for legislation including those who very much support and support legislation was 93.34% in the field survey and 87.68% in the online survey.

Conclusions: E-bike users had lower correct awareness rate than other road users regarding e-bike violation behaviors but were more concerned about safety protection than other road users. E-bike users’ correct practices were far behind their awareness for all kinds of violation behaviors. Public education on the traffic law needs to be strengthened among e-bike users. The public strongly supported special regulations for e-bike use, such as helmet use.  相似文献   
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Severe fluid forces are believed to be a source of injury and mortality to fish that pass through hydroelectric turbines. A process is described by which laboratory bioassays, computational fluid dynamics models, and field studies can be integrated to evaluate the significance of fluid shear stresses that occur in a turbine. Areas containing potentially lethal shear stresses were identified near the stay vanes and wicket gates, runner, and in the draft tube of a large Kaplan turbine. However, under typical operating conditions, computational models estimated that these dangerous areas comprise less than 2% of the flow path through the modeled turbine. The predicted volumes of the damaging shear stress zones did not correlate well with observed fish mortality at a field installation of this turbine, which ranged from less than 1% to nearly 12%. Possible reasons for the poor correlation are discussed. Computational modeling is necessary to develop an understanding of the role of particular fish injury mechanisms, to compare their effects with those of other sources of injury, and to minimize the trial and error previously needed to mitigate those effects. The process we describe is being used to modify the design of hydroelectric turbines to improve fish passage survival.  相似文献   
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The aim of this study was to investigate occupational noise exposure and hearing defects among sawmill workers in the south of Thailand. Seven hundred sawmill workers participated, of which 335 (47.9%) were male. The mean age of the sawmill workers was 33.5 years (SD 10.2), and more than 60% were <35 years old; 75.1% of the workers had less than 5 years of work experience. Only about one in four workers (25%) had been trained in use of personal protective equipment (PPE), and half of the participants never or rarely wore PPE while working. The prevalence rate of noise-induced hearing loss (NIHL) was 22.8% (N?=?42). Male workers had significantly higher risk than female workers (odds ratio [OR]?=?2.21). Workers aged older than 25 years had significantly higher risks for NIHL (OR?=?3.51–12.42) than workers younger than 25 years. Sawing workers had higher risk for NIHL than office workers (OR?=?3.07).  相似文献   
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PROBLEM: Falls represent a significant occupational hazard, particularly in industries with dynamic work environments. This paper describes rates of noncompliance with fall hazard prevention requirements, perceived safety climate and worker knowledge and beliefs, and the association between fall exposure and safety climate measures in commercial aircraft maintenance activities. METHODS: Walkthrough observations were conducted on aircraft mechanics at two participating facilities (Sites A and B) to ascertain the degree of noncompliance. Mechanics at each site completed questionnaires concerning fall hazard knowledge, personal safety beliefs, and safety climate. Questionnaire results were summarized into safety climate and belief scores by workgroup and site. Noncompliance rates observed during walkthroughs were compared to the climate-belief scores, and were expected to be inversely associated. RESULTS: Important differences were seen in fall safety performance between the sites. The study provided a characterization of aircraft maintenance fall hazards, and also demonstrated the effectiveness of an objective hazard assessment methodology. Noncompliance varied by height, equipment used, location of work on the aircraft, shift, and by safety system. DISCUSSION: Although the expected relationship between safety climate and noncompliance was seen for site-average climate scores, workgroups with higher safety climate scores had greater observed noncompliance within Site A. Overall, use of engineered safety systems had a significant impact on working safely, while safety beliefs and climate also contributed, though inconsistently. IMPACT ON INDUSTRY: The results of this study indicate that safety systems are very important in reducing noncompliance with fall protection requirements in aircraft maintenance facilities. Site-level fall safety compliance was found to be related to safety climate, although an unexpected relationship between compliance and safety climate was seen at the workgroup level within site. Finally, observed fall safety compliance was found to differ from self-reported compliance.  相似文献   
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 In PCR-supported amplification of ancient, degraded DNA, contamination with contemporary DNA can lead to false-positive results, which frequently give rise to discussions in which the mere existence of ancient DNA is doubted. Our confirmation of ancient DNA using comparative genome hybridization (CGH) eliminates these doubts. Unlike PCR methods, CGH requires no amplification of the DNA to be analyzed if adequate amounts of specimen DNA is used. Thus, false results traceable to contaminations are practically ruled out. The examples provided here prove the authenticity of ancient DNA for a 250-year-old and a 3000-year-old sample. At the same time, the CGH of ancient DNA offers the chance to gain insight into the pattern of DNA degradation and to monitor the preservation of certain chromosomal segments. Received: 10 May 1999 / Accepted in revised form: 29 July 1999  相似文献   
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