49 resultados para Public Transport Accessibility Level (PTAL)
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
Should a firm stay focused or should it rather adopt a broader strategic perspective? This dissertation summarizes and extends the existing knowledge base on entrepreneurial, market, and learning orientation. Building on multiple theoretical perspectives, empirical evidence from prior studies, as well as on survey and archival data collected in two economic contexts, performance effects from individual orientations, their dimensions and combinations are explored. Results reveal that the three strategic orientations are highly interrelated and that their relationship to firm performance is more complex than previously assumed.
Resumo:
INTRODUCTION About 10,000 escalator-related injuries per year result in emergency department treatment in the United States. Since the 1990s, a steady increase has been reported, but few statistics on escalator-related injuries have been published worldwide. We have therefore analyzed escalator accident statistics in admissions to our hospital in Switzerland since 2000. METHODS Using retrospective electronic patient chart analysis, we included in our study patients >16 years treated over an 11-year period. We categorized patients in terms of gender, age and associated risk factors, and classified accidents according to day, time, location and cause. Resulting trauma was categorized according to type and location. We divided post-admission treatment into surgical and conservative, and into treatment as an outpatient, in a short-stay unit, or as a hospital admission. Women and men were compared using Fisher's exact test. RESULTS We identified 173 patients with 285 discrete injuries. Of these, 87 patients (50%) were women. Fifty-three (61%) of the women and 38 (44%) of the men were >60 years old (P = 0.033). Fifty percent of the men (43/86) of the men, but only 7% (6/87) of the women showed signs of alcohol intoxication (P < 0.0001). Accidents in women occurred predominantly on Tuesdays (19/87; 22%) between 12pm and 6pm (35/87; 40%), and in men on Saturdays (16/86; 19%) between 6pm and 12am (29/86; 34%; P = 0.0097). Sixty-two percent (44/71) of the accidents were in public transport facilities and 30% (21/71) in shopping centers. The majority of injuries in women were to the lower extremities (49/87; 56%), while most accidents in men were to the head and neck (51/86; 59%; P = 0.0052). About half (90; 52%) of the patients were treated conservatively. Almost half of all patients (76, 44%) required hospital admission. Of those, 45% left the hospital within 24 hours of admission (short stay unit) and 55% stayed longer than 24 hours. CONCLUSION Escalator accidents can result in severe trauma. Significant gender differences in escalator accidents have been observed. Alcohol intoxication and age are significant risk factors in escalator-related accidents and might be possible targets for preventive measures.
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Copper, zinc, manganese, iron, nickel and molybdenum are essential micronutrients for plants. However, when present in excess they may damage the plant or decrease the quality of harvested plant products. Some other heavy metals such as cadmium, lead or mercury are not needed by plants and represent pollutants. The uptake into the roots, the loading into the xylem, the acropetal transport to the shoot with the transpiration stream and the further redistribution in the phloem are crucial for the distribution in aerial plant parts. This review is focused on long-distance transport of heavy metals via xylem and phloem and on interactions between the two transport systems. Phloem transport is the basis for the redistribution within the shoot and for the accumulation in fruits and seeds. Solutes may be transferred from the xylem to the phloem (e.g., in the small bundles in stems of cereals, in minor leaf veins). Nickel is highly phloem-mobile and directed to expanding plant parts. Zinc and to a lesser degree also cadmium are also mobile in the phloem and accumulate in meristems (root tips, shoot apex, axillary buds). Iron and manganese are characterized by poor phloem mobility and are retained in older leaves.
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Nowadays, aerosol processes are widely used for the manufacture of nanoparticles (NPs), creating an increased occupational exposure risk of workers, laboratory personnel and scientists to airborne particles. There is evidence that possible adverse effects are linked with the accumulation of NPs in target cells, pointing out the importance of understanding the kinetics of particle internalization. In this context, the uptake kinetics of representative airborne NPs over 30 min and their internalization after 24 h post-exposure were investigated by the use of a recently established exposure system. This system combines the production of aerosolized cerium oxide (CeO(2)) NPs by flame spray synthesis with its simultaneous particle deposition from the gas-phase onto A549 lung cells, cultivated at the air-liquid interface. Particle uptake was quantified by mass spectrometry after several exposure times (0, 5, 10, 20 and 30 min). Over 35% of the deposited mass was found internalized after 10 min exposure, a value that increased to 60% after 30 min exposure. Following an additional 24 h post-incubation, a time span, after which adverse biological effects were observed in previous experiments, over 80% of total CeO(2) could be detected intracellularly. On the ultrastructural level, focal cerium aggregates were present on the apical surface of A549 cells and could also be localized intracellularly in vesicular structures. The uptake behaviour of aerosolized CeO(2) is in line with observations on cerium suspensions, where particle mass transport was identified as the rate-limiting factor for NP internalization.
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Fourteen non-terrorist attackers of public figures in Germany between 1968 and 2004 were intensively studied, with a particular focus on warning behaviors, attack behaviors, and the relationship between psychiatric diagnosis, symptoms, and motivations for the assault. A large proportion of the attackers were severely mentally ill, and most likely to be in the potentially lethal rather than the non-lethal group. A new typology of seven warning behaviors was applied to the data, and all were present, most frequently fixation and pathway warning behavior, and least frequently a direct threat. Psychiatric diagnosis could be closely linked to motivation when analyzed at the level of symptom and content of thought, often delusional. Most of the attacks were directed at political figures, and the majority occurred after 1995.
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Structural analyses of heterologously expressed mammalian membrane proteins remain a great challenge given that microgram to milligram amounts of correctly folded and highly purified proteins are required. Here, we present a novel method for the expression and affinity purification of recombinant mammalian and in particular human transport proteins in Xenopus laevis frog oocytes. The method was validated for four human and one murine transporter. Negative stain transmission electron microscopy (TEM) and single particle analysis (SPA) of two of these transporters, i.e., the potassium-chloride cotransporter 4 (KCC4) and the aquaporin-1 (AQP1) water channel, revealed the expected quaternary structures within homogeneous preparations, and thus correct protein folding and assembly. This is the first time a cation-chloride cotransporter (SLC12) family member is isolated, and its shape, dimensions, low-resolution structure and oligomeric state determined by TEM, i.e., by a direct method. Finally, we were able to grow 2D crystals of human AQP1. The ability of AQP1 to crystallize was a strong indicator for the structural integrity of the purified recombinant protein. This approach will open the way for the structure determination of many human membrane transporters taking full advantage of the Xenopus laevis oocyte expression system that generally yields robust functional expression.
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High-resolution microscopy techniques provide a plethora of information on biological structures from the cellular level down to the molecular level. In this review, we present the unique capabilities of transmission electron and atomic force microscopy to assess the structure, oligomeric state, function and dynamics of channel and transport proteins in their native environment, the lipid bilayer. Most importantly, membrane proteins can be visualized in the frozen-hydrated state and in buffer solution by cryo-transmission electron and atomic force microscopy, respectively. We also illustrate the potential of the scintillation proximity assay to study substrate binding of detergent-solubilized transporters prior to crystallization and structural characterization.
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Partner notification (PN or contact tracing) is an important aspect of treating bacterial sexually transmitted infections (STIs), such as Chlamydia trachomatis. It facilitates the identification of new infected cases that can be treated through individual case management. PN also acts indirectly by limiting onward transmission in the general population. However, the impact of PN, both at the level of individuals and the population, remains unclear. Since it is difficult to study the effects of PN empirically, mathematical and computational models are useful tools for investigating its potential as a public health intervention. To this end, we developed an individual-based modeling framework called Rstisim. It allows the implementation of different models of STI transmission with various levels of complexity and the reconstruction of the complete dynamic sexual partnership network over any time period. A key feature of this framework is that we can trace an individual's partnership history in detail and investigate the outcome of different PN strategies for C. trachomatis. For individual case management, the results suggest that notifying three or more partners from the preceding 18 months yields substantial numbers of new cases. In contrast, the successful treatment of current partners is most important for preventing re-infection of index cases and reducing further transmission of C. trachomatis at the population level. The findings of this study demonstrate the difference between individual and population level outcomes of public health interventions for STIs.