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71.
The purpose of the study was to examine in the blood of overweight men aged from 62 to 83 years, the relationships between age and insulin resistance, selected parameters of the oxidative stress, and the antioxidant defense system. The population studied was divided into two groups: the group ‘young-old’ consisted of men aged 62 to 74 years old, and the group ‘old-old’– of men aged between 75 and 83 years. The total antioxidative status (TAS) and concentrations of thiobarbituric acid reactive substances (TBARS) were measured in the blood plasma. In the serum samples, the levels of antibodies against oxidized LDL (oLAB), glucose, total cholesterol, HDL-cholesterol, triglycerides and insulin were measured. Homeostasis Model Assessment of Insulin Resistance (HOMAIR) was calculated. Concentration of reduced glutathione (GSH) and glutathione peroxidase activity (GPx) were determined in the red blood cells hemolysate. The results of the study did not show significant differences between groups investigated with respect to concentrations of TBARS, TAS, GSH and GPx. However, significantly higher concentrations of glucose and antibodies against oxLDL (p < 0.05) were observed in the group of men over 74 years old in comparison to the group of ‘young-old’ men. It was indicated that the increased insulin resistance and hyperglycemia in elderly men are related to body mass and that they cause intensified oxidative modifications of LDL.  相似文献   
72.
Before full-scale war broke out in 2022, over 1 million Ukrainians resided legally in Poland. Within weeks of Russia's aggression, around 1.5 million new Ukrainian forced migrants had arrived, many of whom remain in Poland. As of September 2023, 970,000 Ukrainian refugees were still in Poland, where they enjoyed temporary protection status. This paper analyses data from a 2022 survey of both forcibly displaced and pre-war Ukrainian migrants with the aim of establishing what measures are needed to facilitate the economic integration of the former group. The two cohorts differ in terms of gender, age, family status, ways of seeking employment, employment situation and aspirations. Although 66 per cent of respondents had completed tertiary education, only 30 per cent of the forcibly displaced group had Polish-language skills. The paper recommends strategies for the provision of language education along with solutions to enable the labour market participation of this group and otherwise support their integration.  相似文献   
73.
74.
This article explores differences in the self‐reported drug use and exposure to drugs of an ethnically diverse group of 408 seventh‐grade students from a large city in the southwest. We contrast the explanatory power of ethnic labels (African American, non‐Hispanic White, Mexican American, and mixed ethnicity) and two dimensions of ethnic identity in predicting drug use. One dimension focuses on perceived ethnically consistent behavior, speech, and looks, while the other gauges a sense of ethnic pride. Ethnic labels were found to be somewhat useful in identifying differences in drug use, but the two ethnic identity measures, by themselves, did not generally help to explain differences in drug use. In conjunction, however, ethnic labels and ethnic identity measures explained far more of the differences in drug use than either did alone. The findings indicate that the two dimensions of ethnic identity predict drug outcomes in opposite ways, and these relations are different for minority students and non‐Hispanic White students. Generally, African American, Mexican American, and mixed‐ethnicity students with a strong sense of ethnic pride reported less drug use and exposure, while ethnically proud White students reported more. Ethnic minority students who viewed their behavior, speech, and looks as consistent with their ethnic group reported more drug use and exposure, while their White counterparts reported less. These findings are discussed, and recommendations for future research are provided.  相似文献   
75.
Value Stream Mapping (VSM) is a very popular tool in lean environments to represent production flows, mapping value stream of a product or family of products, and helps to identify some types of waste. Although very popular, this tool has some limitations as already described in many publications, especially in terms of restrictions in showing most types of waste as well as in its inability to represent various production routes. The purpose of this study is to introduce the waste identification diagram (WID), a new tool to represent production units with its different forms of waste, which overcomes some VSM limitations. The originality of WID comes from the use of its symbols’ dimensions to convey, in a visual and immediate way, relevant information about a production unit. In this paper, WID is applied on a production unit of a lift manufacturer, for testing its performance and comparing it to VSM. The main findings are that WID is in general more effective than VSM in terms of representation of complex production units and in terms of identification of more forms of waste. WID must however overcome some of its limitations such as the lack of information-flow representation and the links to suppliers and clients.  相似文献   
76.
While firm internationalization processes have been understood as being dynamic, the dimension of speed has rarely been the main focus of research efforts, which, until a decade ago, focused principally on explaining sequences of entry modes and choices of markets. The emergence of the study of international entrepreneurship has enhanced the role of speed, although this has usually been measured in terms of the time lag between a firm's foundation and its initial international action, with little attempt at defining and explaining the speed of the process once it is under way. This study reviews the concept of speed from an internationalization perspective, describes the multidimensional nature of the concept and sets out the different aspects that link timescales with the types of changes – continuous and discontinuous – that take place during internationalizing processes. The paper concludes with a research agenda as a guide for future work on considering the role of speed in the internationalization process.  相似文献   
77.
In this paper, we introduce new ways of utilizing preference information specified by the decision maker in interactive reference point based methods. A reference point consists of desirable values for each objective function. The idea is to take the desires of the decision maker into account more closely when projecting the reference point onto the set of nondominated solutions. In this way we can support the decision maker in finding the most satisfactory solutions faster. In practice, we adjust the weights in the achievement scalarizing function that projects the reference point. We identify different cases depending on the amount of additional information available and demonstrate the cases with examples. Finally, we summarize results of extensive computational tests that give evidence of the efficiency of the ideas proposed.  相似文献   
78.
ABSTRACT

Information and communication technologies (ICTs) have enhanced peer communication and contributed to social change and, as such, have become an essential tool in the initial training and professional development of future social work practitioners. In the new millennium, it is particularly important to provide the foundations for delivering appropriate interventions in the fields of social education, social services, healthcare and development cooperation. To face these new challenges, training programmes in the framework of the European Higher Education Area should facilitate the acquisition of skills and competencies through curricula based on ongoing assessment which promote creativity and educational innovation. Through a systematic and comprehensive review of the scientific literature, this article examines the educational potential of e-social work in Spain and the training needs of social workers from an interdisciplinary approach. A critical debate is presented throughout the paper to encourage reflection among professionals. The study highlights the importance of the acquisition of digital skills through the development of educational intervention programmes using the latest technological media and resources with a view to serving citizens in these new spaces of interaction.  相似文献   
79.
We discuss here an alternative approach for decreasing the bias of the closed-form estimators for the gamma distribution recently proposed by Ye and Chen in 2017. We show that, the new estimator has also closed-form expression, is positive, and can be computed for n?>?2. Moreover, the corrective approach returns better estimates when compared with the former ones.  相似文献   
80.
When spatial data are correlated, currently available data‐driven smoothing parameter selection methods for nonparametric regression will often fail to provide useful results. The authors propose a method that adjusts the generalized cross‐validation criterion for the effect of spatial correlation in the case of bivariate local polynomial regression. Their approach uses a pilot fit to the data and the estimation of a parametric covariance model. The method is easy to implement and leads to improved smoothing parameter selection, even when the covariance model is misspecified. The methodology is illustrated using water chemistry data collected in a survey of lakes in the Northeastern United States.  相似文献   
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