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Subclavian steal syndrome: long-term course over 3 years spontaneously and postoperatively (author's transl)

It was studied development of Subclavian Steal Syndrome in 27 patients postoperatively and spontaneously over a period of 3 years. It was seen a high quote of spontaneous recovery of cerebral symptoms, on the other side there was a lack of complete remissions of cerebral symptoms after vascular operation. Vascular operation is only indicated in syncopal and severe ischemic brachial symptoms.     

Transparent, highly sensitive GaAs/(GaAl)As photodiode

The letter describes the performance and properties of a transparent GaAs/(GaAl)As photodiode. The diodo can be inserted directly into an optical-fibre transmission line. By this means, it becomes possible to couple out a small amount of the light power guided within the fibre in tho form of an electrical signal.     

Considering the complexity of microbial community dynamics in food safety risk assessment

The potential for competitive inhibition to limit the growth of microbial pathogens in food raises questions about the external validity of typical predictive microbiology studies and suggests the need to consider microbial community dynamics in food safety risk assessment. Ecological theory indicates, however, that community dynamics are highly complex and may be very sensitive to initial conditions and random variation. Seemingly incongruous empirical results for Escherichia coli O157:H7 in ground beef are shown to be consistent with a simple theoretical model of interspecific competition. A potential means of incorporating community-level microbial dynamics into the food safety risk assessment process is explored.     

Mobilization of arsenic during one-year incubations of grey aquifer sands from Araihazar, Bangladesh

Elevated As concentrations in shallow groundwater pose a major health threat in Bangladesh and similarly affected countries, yet there is little consensus on the mechanism of As release to groundwater or how it might be influenced by human activities. In this study, the rate of As release was measured directly with incubations lasting 11 months, using sediment and groundwater collected simultaneously in Bangladesh and maintained under anaerobic conditions throughout the study. Groundwater and gray sediment were collected as diluted slurries between 5 and 38 m in depth, a range over which ambient groundwater As concentrations increased from 20 to 100 microg L(-1). Arsenic was released to groundwater in slurries from 5 and 12 m in depth at a relatively constant rate of 21 +/- 4 (2 sigma) and 23 +/- 6 microg As kg(-1) yr(-1), respectively. Amendment with a modest level of acetate increased the rate of As release only at 12 m (82 +/- 18 mirog kg(-1) yr(-1)). Although the groundwater As concentration was initially highest at 38 m depth, no release of As was observed. These results indicate that the spatial distribution of dissolved As in Bangladesh and local rates of release to groundwater are not necessarily linked. Iron release during the incubations did not occur concurrently with As release, providing further confirmation thatthe two processes are not directly coupled. Small periodic additions of oxygen suppressed the release of As from sediments at all three depths, which supports the notion that anoxia is a prerequisite for accumulation of As in Bangladesh groundwater.     

A qualitative examination of graduate advising relationships: The advisee perspective.

Sixteen 3rd-year counseling psychology doctoral students were interviewed about their relationships with their graduate advisors. Of those students, 10 were satisfied and 6 were unsatisfied with their advising relationships. Satisfied and unsatisfied students differed on several aspects of the advising relationship, including (a) the ability to choose their advisors, (b) the frequency of meetings with their advisors, (c) the benefits and costs associated with their advising relationships, and (d) how conflict was dealt with in the advising relationship. Furthermore, all of the satisfied students reported that their advising relationships became more positive over time, whereas many of the unsatisfied students reported that their advising relationships got worse (e.g., became more distant) over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Epidemiology and control of egg-associated Salmonella enteritidis in the United States of America

The isolation rate for Salmonella enterica serotype Enteritidis (SE) in humans in the United States of America (USA) increased from 1,207 sporadic isolates identified in 1976 (0.6 isolates/100,000 population) to 10,201 identified in 1995 (4.0/100,000 population). The proportion of reported Salmonella isolates which were SE increased from 5% to 25% during the same time period. In 1990, 1994, and 1995, SE was the most commonly reported reported Salmonella serotype in the USA. Much of this increase has been associated with the consumption of contaminated shell eggs. An examination of the results of a United States Department of Agriculture (USDA) survey of spent hens at slaughter and unpasteurised liquid egg at breaker plants (liquid egg processors) in 1991 and 1995 reveals an increase in the prevalence of SE isolates overall and in most regions of the USA. SE phage type 4 (pt 4), the predominant SE phage type in other parts of the world, has emerged in the egg industry in the western USA concurrent with a sharp increase in the number of sporadic human SE pt 4 isolates in California and Utah. Research on the molecular structure and virulence of SE pt 4 isolates from the USA as compared with isolates from other parts of the world (human and poultry) should be a priority. A comparison of DNA from pt 4 isolates from the USA and Europe may provide information about the potential threat to public health and poultry in the USA from this phage type. Some regional success in the reduction of human illness as a result of SE control efforts is apparent. The Pennsylvania Egg Quality Assurance Program has shown progress in reducing SE infection in participating flocks. At a national level, however, neither the incidence of human illness due to SE nor the prevalence of SE in flocks and unpasteurised liquid eggs have decreased significantly, despite the implementation of the USDA 'trace back' regulation from 1990 to 1995, and intensified efforts to educate food handlers and to enforce safe food handling practices. More effort is needed to control SE at every stage of the egg continuum, from production through to consumption. A risk-reduction approach, with barriers to the introduction and multiplication of the pathogen throughout the farm-to-table continuum, is the most practical method for reducing human illness from SE in shell eggs at present. An effective long-term solution will require interdisciplinary efforts involving government, industry, consumers, and academics. Interventions should be developed and evaluated in compliance with the potential for reducing the risk to human health and cost-effectiveness.     

Degradation of 2-chlorophenol and formation of 2-chloro-1,4-benzoquinone by mycelia and cell-free crude culture liquids of Trametes versicolor in relation to extracellular laccase activity

The white-rot fungus Trametes versicolor was used to study the influence of extracellular laccase activity on the degradation of 2-chlorophenol (2-CP) and the formation of metabolites under conditions, characterized by the absence of other phenol-oxidizing enzymes. 2-CP enhanced the production of extracellular laccase by fungal mycelia. The formation of the metabolite 2-chloro-1,4-benzoquinone (2-CIBQ) was found to be correlated with extracellular laccase activity. In cell-free crude culture liquids laccase was responsible for the oxidation of 2-CP. In contrast to this, the disappearance of 2-CP caused by the entire organism did not correlate with extracellular laccase activity. The primary oxidative step during the degradation of this compound can thus only partially be attributed to extracellular laccase; indicating the involvement of cell-bound processes.