32 resultados para 1960s

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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Whitefish, genus Coregonus, show exceptional levels of phenotypic diversity with sympatric morphs occurring in numerous postglacial lakes in the northern hemisphere. Here, we studied the effects of human-induced eutrophication on sympatric whitefish morphs in the Swiss lake, Lake Thun. In particular, we addressed the questions whether eutrophication (i) induced hybridization between two ecologically divergent summer-spawning morphs through a loss of environmental heterogeneity, and (ii) induced rapid adaptive morphological changes through changes in the food web structure. Genetic analysis based on 11 microsatellite loci of 282 spawners revealed that the pelagic and the benthic morph represent highly distinct gene pools occurring at different relative proportions on all seven known spawning sites. Gill raker counts, a highly heritable trait, showed nearly discrete distributions for the two morphs. Multilocus genotypes characteristic of the pelagic morph had more gill rakers than genotypes characteristic of benthic morph. Using Bayesian methods, we found indications of recent but limited introgressive hybridization. Comparisons with historical gill raker data yielded median evolutionary rates of 0.24 haldanes and median selection intensities of 0.27 for this trait in both morphs for 1948-2004 suggesting rapid evolution through directional selection at this trait. However, phenotypic plasticity as an alternative explanation for this phenotypic change cannot be discarded. We hypothesize that both the temporal shifts in mean gill raker counts and the recent hybridization reflect responses to changes in the trophic state of the lake induced by pollution in the 1960s, which created novel selection pressures with respect to feeding niches and spawning site preferences.

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Plutonium is present in the environment as a consequence of atmospheric nuclear tests, nuclear weapons production and industrial releases over the past 50 years. To study temporal trends, a high resolution Pu record was obtained by analyzing 52 discrete samples of an alpine firn/ice core from Colle Gnifetti (Monte Rosa, 4450 m a.s.l.), dating from 1945 to 1990. The 239Pu signal was recorded directly, without decontamination or preconcentration steps, using an Inductively Coupled Plasma - Sector Field Mass Spectrometer (ICP-SFMS) equipped with an high efficiency sample introduction system, thus requiring much less sample preparation than previously reported methods. The 239Pu profile reflects the three main periods of atmospheric nuclear weapons testing: the earliest peak lasted from 1954/55 to 1958 and was caused by the first testing period reaching a maximum in 1958. Despite a temporary halt of testing in 1959/60, the Pu concentration decreased only by half with respect to the 1958 peak due to long atmospheric residence times. In 1961/62 Pu concentrations rapidly increased reaching a maximum in 1963, which was about 40% more intense than the 1958 peak. After the signing of the "Limited Test Ban Treaty" between USA and USSR in 1964, Pu deposition decreased very sharply reaching a minimum in 1967. The third period (1967-1975) is characterized by irregular Pu concentrations with smaller peaks (about 20-30% of the 1964 peak) which might be related to the deposition of Saharan dust contaminated by the French nuclear tests of the 1960s. The data presented are in very good agreement with Pu profiles previously obtained from the Col du Dome ice core (by multi-collector ICP-MS) and Belukha ice core (by Accelerator Mass Spectrometry, AMS). Although a semi-quantitative method was employed here, the results are quantitatively comparable to previously published results.

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Structured cardiac rehabilitation goes back to the late 1960s also in Switzerland and in the beginning was only available in rehabilitation clinics. In 1972 the first ambulatory rehabilitation programs became available to patients in Zurich and Bern. In the following years, in addition to the increasing number of rehabilitation centers for inpatients, more and more ambulatory rehabilitation programs were developed, especially in the larger Midlands population area in German and French-speaking Switzerland. In 1985 the Swiss Working Group of Cardiac Rehabilitation (SAKR) was initiated as an official working group of the Swiss Society of Cardiology and one of its first tasks was to establish a list of the institutions for cardiac rehabilitation in Switzerland. At that time there were 42 rehabilitation programs for a population of approx. 6.5 million, 21 for inpatients and 21 ambulatory; however, 90% of the patients were in inpatient programs. In 1992 the SAKR group defined the quality criteria which were to be applied for official recognition of institutions for cardiac rehabilitation in Switzerland. Due to these criteria, plus the fact that an increasing number of rehabilitation clinics in the mountains had been closed down, the number of inpatient rehabilitation centers decreased from 21 to 11 between 1989 and 2011, whereas the number of ambulatory programs increased from 21 to 51. The ambulatory rehabilitation centers are partially organized by local medical groups; however, most have integrated their activities into the local hospitals. The trend shows a developing preference for ambulatory rehabilitation. More and more elderly, polymorbid patients, however, will still need care in inpatient programs.

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Herbal drugs are being increasingly used in medical practice, often without appropriate scrutiny of their safety and efficacy. The medicinal product Padma 28 is a fixed combination with Tibetan origin, used in Europe since the 1960s for the symptomatic treatment of circulatory disorders, including those of peripheral arterial occlusive disease (PAOD). We have conducted an analysis of all available data on this herbal drug from published literature as well as from original data we obtained from contacting the authors of published papers, reports and the manufacturer. A total of 19 trials have reported on 2084 patients to date, 444 of whom were in six controlled clinical studies on PAOD. A meta-analysis of five trials showed Padma 28 to increase walking distance by >100m in 18.2% of the patients with verum, versus 2.1% with placebo (P<0.001; odds ratio: 10 [95% CI 3.03, 33.33]; RR: 0.12; number needed to treat=6.2). The safety profile appears to be favourable. Available evidence shows that Padma 28 provides significant relief from PAOD-related symptoms (i.e. walking distance), probably of the same order of magnitude as other employed medications. However, larger confirmatory RCTs are desirable.

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The shift of psychiatric care from the hospital to the community has been accompanied by a reduction of hospital beds and shortened durations of inpatient treatment, but also by an increase in admissions. This evolution may be largely attributed to the prime focus of community mental health institutions on rehabilitation. The continued implementation of reforms in psychiatric care is contingent upon effectively halting the "revolving door phenomenon" by incorporating community-integrated treatment approaches into the care of acutely ill patients. Since the mid-1960s, a series of studies have established the efficacy of two community-integrated modalities for the treatment of acute psychiatric illness, i.e. home-based and day hospital treatment. In general, these approaches not only seem to be as effective as inpatient care for certain groups of patients but also reduce their need of hospitalisation, thereby contributing towards a cost effective, comprehensive psychiatric care system.

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We investigate whether negative postacquisition stock-price performance of acquiring firms is a genuine phenomenon or a statistical artifact. Using a comprehensive sample of domestic acquisitions in the 1966-1986 period, we show that acquiring firms underperform a control portfolio only during the three years but not five years following the acquisition. There is evidence of negative performance in the second and third postacquisition years, but that performance occurs mainly in the 1960s and 1970s, and disappears in the 1980s. Thus, especially in the later years, the postacquisition years do not provide convincing evidence of wasteful corporate acquisitions, or strong evidence that contradicts market efficiency.

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A lack of quantitative high resolution paleoclimate data from the Southern Hemisphere limits the ability to examine current trends within the context of long-term natural climate variability. This study presents a temperature reconstruction for southern Tasmania based on analyses of a sediment core from Duckhole Lake (43.365°S, 146.875°E). The relationship between non-destructive whole core scanning reflectance spectroscopy measurements in the visible spectrum (380–730 nm) and the instrumental temperature record (ad 1911–2000) was used to develop a calibration-in-time reflectance spectroscopy-based temperature model. Results showed that a trough in reflectance from 650 to 700 nm, which represents chlorophyll and its derivatives, was significantly correlated to annual mean temperature. A calibration model was developed (R = 0.56, p auto < 0.05, root mean squared error of prediction (RMSEP) = 0.21°C, five-year filtered data, calibration period 1911–2000) and applied down-core to reconstruct annual mean temperatures in southern Tasmania over the last c. 950 years. This indicated that temperatures were initially cool c. ad 1050, but steadily increased until the late ad 1100s. After a brief cool period in the ad 1200s, temperatures again increased. Temperatures steadily decreased during the ad 1600s and remained relatively stable until the start of the 20th century when they rapidly decreased, before increasing from ad 1960s onwards. Comparisons with high resolution temperature records from western Tasmania, New Zealand and South America revealed some similarities, but also highlighted differences in temperature variability across the mid-latitudes of the Southern Hemisphere. These are likely due to a combination of factors including the spatial variability in climate between and within regions, and differences between records that document seasonal (i.e. warm season/late summer) versus annual temperature variability. This highlights the need for further records from the mid-latitudes of the Southern Hemisphere in order to constrain past natural spatial and seasonal/annual temperature variability in the region, and to accurately identify and attribute changes to natural variability and/or anthropogenic activities.

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At the beginning of the 20th Century, cervical cancer was the leading cause of death from cancer in women. A marked decline in cervical cancer has been observed since the 1960s, in parallel with the introduction of the Papanicolau (Pap) test as a cytological screening method. Today, Pap smear screening is still the most widely used tool for cervical cancer prevention. Testing for human papillomavirus (HPV) in cervical specimens or a combination of Pap and HPV testing are also now available. In this article we compare current guidelines for cervical cancer screening in Switzerland with those in other European countries. In view of the opportunities offered by HPV testing and, since 2008, HPV vaccination, current guidelines for cervical cancer screening should be updated. Both the choice of screening tests and general organization of cervical cancer screening should be reviewed.

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Since the 1960s the ilioinguinal approach by Letournel with the three anatomic windows has been successfully established for the treatment of acetabular fractures involving predominantly the anterior column. The previous standard approach, the iliofemoral approach by Smith-Petersen, is still used for the therapy of anterior wall or isolated femoral head fractures. The increase in acetabular fractures in the elderly with lateral compression fractures after lateral falls, characterized by medial displacement of the quadrilateral plate and superomedial dome impaction, led to the use of the intrapelvic modified Stoppa approach with or without the first window of the ilioinguinal approach in the 1990s. To combine the advantages of the second and third windows of the ilioinguinal approach and the medial view of the modified Stoppa approach the Berne research group recently introduced the pararectus approach in acetabular surgery, which can be used as a less invasive acetabular surgical (LIAS) technique especially in the elderly.

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The incidence of human brucellosis in Kyrgyzstan has been increasing in the last years and was identified as a priority disease needing most urgent control measures in the livestock population. The latest species identification of Brucella isolates in Kyrgyzstan was carried out in the 1960s and investigated the circulation of Brucella abortus, B. melitensis, B. ovis, and B. suis. However, supporting data and documentation of that experience are lacking. Therefore, typing of Brucella spp. and identification of the most important host species are necessary for the understanding of the main transmission routes and to adopt an effective brucellosis control policy in Kyrgyzstan. Overall, 17 B. melitensis strains from aborted fetuses of sheep and cattle isolated in the province of Naryn were studied. All strains were susceptible to trimethoprim-sulfamethoxazole, gentamicin, rifampin, ofloxacin, streptomycin, doxycycline, and ciprofloxacin. Multilocus variable number tandem repeat analysis showed low genetic diversity. Kyrgyz strains seem to be genetically associated with the Eastern Mediterranean group of the Brucella global phylogeny. We identified and confirmed transmission of B. melitensis to cattle and a close genetic relationship between B. melitensis strains isolated from sheep sharing the same pasture.

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This investigation attempts to answer the question why more and more parents have chosen the Gymnasium for their children's secondary school education in post‐war West Germany. Based on the theory of subjective expected utility, the crucial mechanisms of parental educational decisions have been emphasized. From this perspective it is assumed that increasing educational motivation coupled with changes in the subjective evaluation of the cost–benefit of education were important conditions for an increasing participation in upper secondary schools. These were, however, in turn, the result of educational expansion. The empirical analyses for three time‐periods in the 1960s, 1970s, and 1980s confirm these assumptions to a large degree. Additionally, empirical evidence was found to suggest that in addition to the intentions of parents and the educational career of their children, structural moments of educational expansion and their own inertia played an important role in the pupils' transition from one educational level to the next. Finally, evidence was found that persistent class‐specific educational inequality stems from a constant balance in the relative cost–benefit advantages between social classes as well as from an increasing difference of primary origin effect between social classes in the realization of their educational choice.