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The process of transformation of Bulgarian agriculture from a centrally controlled economy to a market-oriented economy is resulting in land reform, which will necessitate the immediate development and operation of land markets. On the one hand, the land reform is restoring land to those who owned it in the year 1947, or their heirs, who not only have very small and scattered holdings, but who often live in urban areas far from the claimed land and do not practice farming. On the other hand, farming is being changed by the liquidation of the former collective farms and the emergence of privately managed farms and new forms of co-operatives. These new operating units may or may not have their own land claims, but in most cases, do not have immediate access to sufficient land for adequately sized operations. Without land market institutions for information, contracting land use, and enforcement of contractual rights, the transaction costs of bringing the suppliers of land together with those demanding land will result in unused land and distorted agricultural activity. The paper explores both the formation of institutions and the evidence of transactions, as well as the possible impacts on farming.  相似文献   
2.
European countries were economically and politically separated during the Cold War, but since its end processes of globalization and the formation of the European Union have contributed to blur the borders. Previous studies suggest that the social transformations have affected differently civic participation of youths, but shortage of more recent data has precluded researchers from examining the differences in a country-comparative fashion. Along these lines, this paper has two main objectives: to explore the differences in the levels of expected civic participation across Europe, and to evaluate the fit of a theoretical model of civic participation in regard to the different points in time their democracies were established. To achieve these goals, data from 22 European educational systems (9 post-communist and 13 established democracies) participating in the International Civic and Citizenship Study (2009) conducted by International Association for the Evaluation of Educational Achievement is used. The results, in accordance with the literature, suggest differentiated patterns of future civic participation between the new and established democracies, but they are not that clear, suggesting that convergence between the two groups is ongoing. However, the tested empirical model of civic participation functions in a better way in the established than in the new democracies. In contrast with previous findings, differences in levels of expected civic participation seem to be related not only with the countries’ experience with democracy, but also with their cultural similarities and common history.  相似文献   
3.
Objective. To determine the prevalence of osteoporosis at the distal forearm in a male cohort referred for bone density testing and to compare it to published data of Bulgarian women.

Design and subjects. 315 consecutive Bulgarian men aged 20 to 84 years were included (mean age 53.74 ± 14.67 years). 59% of them were self-referrals. The comparative female group consisted of 8869 Bulgarian women whose forearm bone mineral density (BMD) was measured in another study.

Measurements. BMD was measured by single X-ray absorptiometry at the distal forearm (distal and ultradistal sites) in all men. T-scores were calculated from manufacturer-provided Danish male reference data.

Results. The ratio of female to male patients was 28.2 (8869 to 315). Peak BMD was observed in men aged 30 to 39 years: 0.560 ± 0.065 g/cm2 (distal site) and 0.490 ± 0.070 g/cm2 (ultradistal site). A steady BMD decline followed reaching 0.492 ± 0.064 g/cm2 at the distal and 0.412 ± 0.069 g/cm2 at the ultradistal site in age group >70. Age had a rather weak negative impact on forearm BMD described by a linear model. In men aged over 50 years the prevalence of osteoporosis at the distal site was 21.19%, compared to 20.45% in women. Low bone mass was seen in 48.77% of men and 32.50% of women. Normal BMD was more frequent in women (47.05%) than in men (30.04%).

Conclusions. We found a high prevalence of forearm osteoporosis in Bulgarian men which is comparable to that already known in women.  相似文献   
4.
ABSTRACT

Statistical methods are effectively used in the evaluation of pharmaceutical formulations instead of laborious liquid chromatography. However, signal overlapping, nonlinearity, multicollinearity and presence of outliers deteriorate the performance of statistical methods. The Partial Least Squares Regression (PLSR) is a very popular method in the quantification of high dimensional spectrally overlapped drug formulations. The SIMPLS is the mostly used PLSR algorithm, but it is highly sensitive to outliers that also effect the diagnostics. In this paper, we propose new robust multivariate diagnostics to identify outliers, influential observations and points causing non-normality for a PLSR model. We study performances of the proposed diagnostics on two everyday use highly overlapping drug systems: Paracetamol–Caffeine and Doxylamine Succinate–Pyridoxine Hydrochloride.  相似文献   
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