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Higher education in a specific way predisposes to disseminate sport and recreation, as well as to create fashion for healthy lifestyle. The main purpose of present publication is to show the results of selected motoric tests and examined basic somatic build parameters. The research were carried among 61 first academic year female students and 60 second academic year female students of Higher Vocational State School in Włocławek -- participants of obligatory physical education aerobic activity. Informations about female students somatic build and selected motorical abilities were collected according to material statistical analysis. [ABSTRACT FROM AUTHOR]

The transport pattern of the organochlorine pollutants along the river-bed is an important issue due to their accumulation in reservoir bottom sediments and bioaccumulation in the food chain. In this study, seventeen most toxic 2,3,7,8-substituted dibenzo-para-dioxins (PCDDs) and dibenzofurans (PCDFs) were selected to determine sediment contamination in a cascade of five urban reservoirs. The total concentrations of PCDD/Fs ranged from 22.98 to 254.56 ng kg-1 d.w. with the mini,mum in the first reservoir, maximum in the middle reservoir, and decline at the end of the reservoirs' cascade. Concentrations of 2,3,7,8-tetrachiorinated dibenzo-para-dioxin (TeCDD) equivalents (TEQs) estimated based on WHO-TEFs decreased along the reservoir cascade (4.94; 3.02; 1.51 and 0.52 ng kg-1 of d.w., respectively), excluding the first one (0.80 ng kg-1 of d.w.). This situation can be related to the hydraulic transport and deposition of PCDD/Fs along the cascade system. The PCDD/PCDF ratio showed a different pattern with the pre-dominance of PCDFs in the first two cascade reservoirs (61.01% and 88.75%, respectively) and PCDDs in the last three reservoirs (86.16%, 87.83% and 91.41%, respectively). [ABSTRACT FROM AUTHOR]

Selected recent QCD and top-quark results from the Tevatron are reviewed, aiming to illustrate progression from basic studies of QCD processes to verification of perturbative calculations and Monte Carlo simulation tools, and to their applications in more novel and complex cases, like top-quark studies and searches for new physics. [ABSTRACT FROM AUTHOR]

Abstract: Many pharmacological investigations have demonstrated that antidepressant agents profoundly affect serotonergic and noradrenergic neurotransmission. The molecular mechanisms by which these drugs exert their therapeutic action have not been clearly established. In our study, the possibility that antidepressant drug action is associated with dopamine neurotransmission was examined. To this end, the effect of 21-day treatment with 10 mg/kg of amitryptyline, mirtazapine and sertraline on the striatal and nucleus accumbens dopamine receptors was verified. The striatum and nucleus accumbens tissues were dissected 24 h after the last dose of the drug and total RNA was isolated. The expression of dopamine D1 to dopamine D5 receptors using reverse-transcriptase polymerase chain reaction (RT-PCR) procedure was compared to the glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) as constitutive gene activation internal control. Lab Works UV program has analyzed the mean optical density values of RT-PCR products. Statistical comparison of relative optical densities by a one-way analysis of variance (ANOVA) followed by Dunnett''s test was performed. Despite their different pharmacological profiles, all three above-presented antidepressants significantly increased dopamine D1 mRNA content. Our findings indicate that repeated antidepressant administration triggers induction of the brain dopaminergic receptors which is correlated with neuroadaptation of the brain dopaminergic pathway. [Copyright &y& Elsevier]

The construction and design process of the time-interval measuring system of resolution 500 ps is discussed in this paper. Such a system can be applied in the construction of a real-time multichannel scalar (RTMS) designed for time-of-flight (TOF) mass spectrometry or lifetime decay measurements. Moreover, a high-resolution time-interval measuring system can be designed for light detection and ranging (LIDAR) system and ultrasonic flowmeters. We present the new high-resolution time-interval measuring system implemented in the single field programmable gate array (FPGA) structure. [Copyright &y& Elsevier]

The European Green Deal strategy, prepared in 2019, involves a number of challenges for European agriculture. These challenges are broadly linked to a need for agriculture to undertake actions in order to improve environmental and climate protection, which will require changes in agricultural practices and the currently observed industrialization processes of agriculture that are destabilizing ecosystems and climate. In view of the diversity of agriculture and its impacts on the environment, it is important to identify the challenges faced by the EU Member States. The aim of this paper is to identify the main environmental and climate challenges that agriculture in Poland will have to face due to the current European Green Deal strategy and its objectives, taking into account the organizational changes in this sector so far and the existing forms of environmental protection in rural areas. The paper is based on empirical data from the Farm Structure Survey conducted by Statistics Poland in 2005, 2007 and 2016, data on greenhouse gas emissions of agricultural origin gathered by the National Centre for Emissions Management (KOBiZE), data from the European Commission, the General Directorate for Environmental Protection and the Institute of Soil Science and Plant Cultivation—State Research Institute concerning the delimitation of the Natura 2000 areas in Poland and the Institute of Agricultural and Food Economics—National Research Institute on three national variants of High Nature Value Farmland areas delimited for the needs of the European Commission, as well as data from the Ministry of Agriculture and Rural Development regarding the delimitation of the less favoured areas with high natural value. In addition, a literature review was conducted indicating the links between agriculture, the environment and climate. The results of the study illustrate the state of Polish agriculture and the changes in this sector in the context of environmental and climate challenges. The results also identify the most difficult areas that will require practical solutions in the future to implement the European Green Deal strategy in Poland. The findings will provide an important basis for policy makers in terms of effective support of agriculture and for the scientific community with regard to agricultural research, which should be particularly developed in order to be able to adapt the agricultural sector to new challenges. [ABSTRACT FROM AUTHOR]

In this paper, polymer composites based on polylactide (PLA) and epoxy resin (Epidian 5) were studied in terms of the influence of magnetic induction on their changes in physicochemical properties. The composites contained admixtures in the form of magnetite (Fe3O4) and crystalline cellulose (Avicel PH-1010) in the amount of 10%, 20%, and 30% by weight and starch in the amount of 10%. The admixtures of cellulose and starch were intended to result in the composites becoming biodegradable biopolymers to some extent. Changes in physical and chemical properties due to the impact of a constant magnetic field with a magnetic induction value B = 0.5 T were observed. The changes were observed during tests of tensile strength, bending, impact strength, water absorbency, frost resistance, chemical resistance to acids and bases, as well as through SEM microscopy and with studies of the composition of the composites that use the EDS method and of their structure with the XRD method. Based on the obtained results, it was found that the magnetic induction value changes the properties of composites. This therefore acts as one method of receiving new alternative materials, the degradation of which in the environment would take far less time. [ABSTRACT FROM AUTHOR]

The aim of the research presented in the paper was to obtain new polymer composites with strong functional properties on the Epidian 5 epoxy resin matrix. The polymer composites contained admixtures of expanded graphite, powder graphite, birch bark containing botulin, and yellow dextrin in set amounts of 20% by weight. Their various mechanical parameters and physicochemical properties were investigated. The research involved determining the effect of a constant magnetic field with magnetic induction B, under the influence of which the parameters and properties of polymer composites have been changed. For example, in a constant magnetic field with an induction of B = 0.5 T there was an increase in the hardness of the composite with an admixture of birch bark from 24.01 to 26.96 N/mm2 (12.3%), or in the composite with the addition of yellow dextrin from 26.12 to 29.93 N/mm2 (14.6%). It was also found, for example, that the water absorption of the resin itself decreased from 0.18% to 0.13%, and the composite with graphite powder from 0.48% to 0.46%. Changes in these parameters, often beneficial, may be important in terms of potential application of those new materials in industry as alternatives. [ABSTRACT FROM AUTHOR]

The objective of this paper is to enhance the dominant research perspective of innovations in the food market (power or supply chain centric) with an interactive/network approach. Many scholars identify the development challenges facing the food sector, including economic factors, changes in lifestyle, climate change, changes to the food consumption mix, shrinkage of Earth's resources and interactions between food production and the environment, in the context of sustainable development. A new approach to innovations in the food market may shift it towards a more sustainable path of development. Based on a literature review, we present the specific conditions for innovation in the food market and discuss previous research as being focused on the power of operators and flows in supply chains. Methodologically, this paper puts these considerations in the context of interaction and business networks. We note that the concept of power and dependence can be embedded with the concept of interdependence, and flows in supply chains can be replaced by the concept of cooperation in business networks. We conceptualize a research framework based on innovative activities in business relationships and networks and we propose the following themes as research avenues for further research: (1) What drives innovation in food ecosystems? (2) When is the power-centric approach to innovations more effective than taking the perspective of interdependence? (3) How do network-born innovations develop in the food sector? (4) How do actors handle innovation in their business models? (5) What is the impact of innovations on the food sector? [ABSTRACT FROM AUTHOR]