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Iniencephaly is an uncommon, but not rare, lesion involving a fusion between the posterior occipital bone and the cervical spine. Many cases are associated with other cranio-cervical abnormalities and anencephaly, and most are associated with other structural abnormalities. The prognosis is thought to be dismal. We describe a male infant, one of twins, who was diagnosed prenatally as having iniencephaly. The child was born without complication and has grown and thrived. This is the fourth patient with long-term survival with iniencephaly. We recommend that non-directive counselling be applied when presenting the findings of iniencephaly to parents.  相似文献   
2.
Animals disperse in space through different movement behaviors, resulting in different displacement distances. This is often described with a displacement kernel where the long-distance dispersers are within the tail of the kernel. A displacement with a large proportion of long-distance dispersers may have impact on different aspects of spatial ecology such as invasion speed, population persistence, and distribution. It is, however, unclear whether the kurtosis of the kernel plays a major role since a fatter tail also influences the variance of the kernel. We modeled displacement in landscapes with different amounts and configurations of habitats and handled kurtosis and variance separately to study how these affected population distribution and transition time. We conclude that kurtosis is not important for any of these aspects of spatial ecology. The variance of the kernel, on the other hand, was of great importance to both population distribution and transition time. We argue that separating variance and kurtosis can cast new light on the way in which long-distance dispersers are important in ecological processes. Consequences for empirical studies are discussed.  相似文献   
3.
Calculations of large-scale displacement distances were made to evaluate the combined effect of small-scale movement pattern of a Collembola, Protaphorura armata. The effect of presence of food and conspecific density on turning angle, step length and activity/motility was investigated. Calculations of net square displacement were made both by assuming correlated random walk (CRW) and by resampling data to account for correlation structures in movement patterns that violate the assumptions of CRW.  相似文献   
4.
Employer commitment is a key factor in an effective safety program, yet limited research has focused on the safety priorities of retail store managers. To address this, the U.S. National Institute for Occupational Safety and Health recruited 4 experienced ergonomists, who met and interviewed 9 retailers in different parts of the eastern USA. The reports from the 9 interviews were used to document the hazards facing retailers and the interventions they attempted. Those interviewed were managers/owners of establishments that ranged from a small bakery with 11 employees to a supermarket with 85 or more employees. The main hazards across all establishments included overexertion, contact-with-objects, and falls-to-the-same-level. We also compared the retailers’ perceptions of safety hazards with injuries from actual hazards as supplied by the U.S. Bureau of Labor Statistics. This report provides insight into the retailers ‘ perceptions of safety hazards as well as their commitment to the prevention of workplace injuries.  相似文献   
5.
OBJECTIVE: The probability of re-arrest for driving while intoxicated (DWI) is compared for four different groups of individuals classified by whether the individual was convicted and, if so, the type of sentence received. METHOD: Subsequent re-arrests for DWI were examined for all individuals whose index arrest for DWI had occurred between 1994 and 2001 in a county in New Mexico. The groups included (1) those convicted as a result of the index arrest and sentenced to a 28-day jail/treatment program (N (#)=(#) 2,703); (2) all those not convicted as a result of the index arrest (N = 709); (3) those who were convicted but not sentenced to jail (N = 1,047); and (4) those convicted and sentenced to jail (N = 1,290). RESULTS: Adjusting for covariates of BAC, number of prior arrests, ethnicity, age, and sex, the probability of not being re-arrested was greatest among those sentenced to the jail/treatment program (Group 1), next highest in the two groups convicted but not sentenced to jail/treatment (Groups 3 and 4), and lowest in the group that was not convicted (Group 2). Length of jail sentence among people convicted but not sentenced to the jail/treatment program was unrelated to the probability of re-arrest. CONCLUSION: Conviction for DWI, regardless of the sentence, appears to reduce the probability of re-arrest, and being sentenced to a multi-modal treatment/incarceration program further reduces the probability of re-arrest. However, the other types of sentences do not appear to differ in their impact on probability of re-arrest.  相似文献   
6.
Twenty evaluations of reported biomechanical hazards were performed by the National Institue for Occupational Safety and Health (NIOSH) at the request of industrial workers or management over an 8-year period. The evaluations were part of the Hazard Evaluation and Technical Assistance (HETA) program authorized under the Occupational Safety and Health Act of 1970. A number of these evaluations are described here. Principles drawn from the field of ergonomics were used to evaluate whether a certain work activity has caused an observed incidence of cumulative trauma to the neuro-musculo-skeletal system. Procedures for conducting these ergonomic evaluations are reviewed, and the results are summarized. Recommendations are made for implementing control procedures, and the problem of obtaining reliable follow-up information is discussed. Project results suggest an encouraging degree of success in accomplishing prevention and control of biochemical hazards in the workplaces studied.  相似文献   
7.
Butyltins were monitored at over eighty sites, primarily marinas, in surface waters and sediments of the California coast. Values of tributyltin (TBT) in marina waters ranged from 20 to 600 ppt while lower values were usually found in harbors and on the coast. The origin of the tributyltin is in its use as an antifouling agent in marine paints. In those marinas where the concentrations are greater than about 100 ppt, there is usually a conspicuous absence of native organisms, especially molluscs, which are among the most sensitive animals to the highly toxic TBT. The impact of TBT upon not-target organisms recalls the DDT episode of the 1970s. Increasing uses of TBT-containing antifouling paints in the future may have even more drastic effects on coastal organisms than those observed today. The conclusion is inescapable that TBT should be banned for use in commercially available marine paints.  相似文献   
8.
Bilateral renal agenesis is a lethal congenital anomaly. It appears to be transmitted in a polygenic pattern. The prenatal ultrasound findings consist of severe oligohydramnios, absence of the fetal bladder, and failure to identify fetal kidneys. Twin gestations with renal agenesis have been described in the paediatric literature. We detail a case of a patient with two prior affected pregnancies with bilateral renal agenesis. Her latest pregnancy was diagnosed prenatally, with one fetus with bilateral and the other fetus with unilateral renal agenesis. The ultrasound findings should be differentiated from the stuck twin phenomenon.  相似文献   
9.
Offshore windmills and the effects of electromagnetic fields on fish   总被引:1,自引:0,他引:1  
Ohman MC  Sigray P  Westerberg H 《Ambio》2007,36(8):630-633
With the large scale developments of offshore windpower the number of underwater electric cables is increasing with various technologies applied. A wind farm is associated with different types of cables used for intraturbine, array-to-transformer, and transformer-to-shore transmissions. As the electric currents in submarine cables induce electromagnetic fields there is a concern of how they may influence fishes. Studies have shown that there are fish species that are magneto-sensitive using geomagnetic field information for the purpose of orientation. This implies that if the geomagnetic field is locally altered it could influence spatial patterns in fish. There are also physiological aspects to consider, especially for species that are less inclined to move as the exposure could be persistent in a particular area. Even though studies have shown that magnetic fields could affect fish, there is at present limited evidence that fish are influenced by the electromagnetic fields that underwater cables from windmills generate. Studies on European eel in the Baltic Sea have indicated some minor effects. In this article we give an overview on the type of submarine cables that are used for electric transmissions in the sea. We also describe the character of the magnetic fields they induce. The effects of magnetic fields on fish are reviewed and how this may relate to the cables used for offshore wind power is discussed.  相似文献   
10.
We provide algebraic simplifications for the redundancy analysis (RDA) eigenvalue and the canonical correspondence analysis (CCA) eigenvalue in the special case of permanent plots sampled twice. The indices for RDA and CCA are interrelated and are intuitively interpretable. These simplifications also apply to simple split-plot designs and to a balanced design with two independent samples.  相似文献   
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