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Self-organised formation of nanotubes from graphene ribbons. A molecular dynamics study

Ibolya Zsoldos Istvan Laszlo David Fulep

Publication Name: Materials Research Express

Publication Date: 2016-10-01

Volume: 3

Issue: 10

Page Range: Unknown

Description:

The conditions for self-organised formations of carbon nanotubes from two parallel graphene ribbons were studied in a density functional adjusted tight binding molecular dynamics simulation.Wehave found that the seemingly trivial process is significantly limited by the thermal motion of the carbon atoms. There are further difficulties as well, primarily the unfavourable position of the atoms at the edges of the zigzag graphene ribbons. In repeated molecular dynamics runs we analysed the conditions of perfect coalescences, the influence of the substrate and the impact of the zigzag graphene ribbon positions.Wehave obtained that contrary to the abovementioned unfavourable conditions perfect nanotube production can be obtained using substrates. As the positioning of the substrate can be made with piezoelectric devices, this can significantly help the experimental realisation of the nanotube formation as well.

Open Access: Yes

DOI: 10.1088/2053-1591/3/10/105044

Randomized controlled resistance training based physical activity trial for central European nursing home residing older adults

Ferenc Ihász József Bognár Sandor Dorgo Judit Kopkáné Plachy István Barthalos Teodóra Ráczné Németh Zsolt Szakály

Publication Name: Journal of Sports Medicine and Physical Fitness

Publication Date: 2016-10-01

Volume: 56

Issue: 10

Page Range: 1249-1257

Description:

Background: Nursing home residing older adults often experience fear of sickness or death, functional impairment and pain. It is diffcult for these older adults to maintain a physically active lifestyle and to keep a positive outlook on life. This study evaluated the changes in quality of life, attitude to aging, assertiveness, physical ftness and body composition of nursing home residing elderly through a 15-week organized resistance training based physical activity program. METHODS: Inactive older adults living in a state fnanced nursing home (N.=45) were randomly divided into two intervention groups and a control group. Both intervention groups were assigned to two physical activity sessions a week, but one of these groups also had weekly discussions on health and quality of life (Mental group). Data on anthropometric measures, ftness performance, as well as quality of life and attitudes to aging survey data were collected. due to low attendance rate 12 subjects were excluded from the analyses. Statistical analysis included paired Samples t-tests and repeated Measures analysis of Variance. RESULTS: Both intervention groups signifcantly improved their social participation, and their upper-and lower-body strength scores. Also, subjects in the Mental group showed improvement in agility ftness test and certain survey scales. No positive changes were detected in attitude towards aging and body composition measures in any groups. The post-hoc results suggest that Mental group improved signifcantly more than the control group. coNcluSioNS: regular physical activity with discussions on health and quality of life made a more meaningful difference for the older adults living in nursing home than physical activity alone. Due to the fact that all participants were in?uenced by the program, it is suggested to further explore this area for better understanding of enhanced quality of life.

Open Access: Yes

DOI: DOI not available

Selling and pricing practices in the direct sales of producer’s raw cow’s milk

Gábor Császár András Jancsó László Varga

Publication Name: Elelmiszervizsgalati Kozlemenyek

Publication Date: 2016-09-30

Volume: 62

Issue: 3

Page Range: 1190-1223

Description:

Among our objectives were the presentation of the most well-known sales channels of raw milk, sales practices and also the technological level used, as well as the examination of the issues related to the pricing, critical points and challenges of the direct sales of raw cow’s milk. Our observations and samplings were performed at 21 direct sales locations of eight Budapest districts over 13 months, from June 2013 through June 2014. Based on the results, it can be stated that, in the area studied, the sale of raw milk is realized through three main sales channels: markets (market halls), self-service systems (milk vending machines, refrigerated store containers) and different forms of mobile sales (tankers, regional home delivery system of producers). Further marketing practices can be distinguished within the different sales channels, where one can find the most primitive practice, the one without cooling, the traditional one and one that can be considered modern even when compared to Western European practice. The theoretical possibility to sell high quality raw milk was available for all sales channels, but the level of sales – especially from hygienic and technological viewpoints – ranged widely. Based on changes in the sales price of raw milk, and its correlation with wholesale buying prices and pasteurized milk prices, it can be assumed that market prices and supply and demand are closely followed by shareholders of the market. Analyzing the mutually influencing effect of the prices of sellers located close to each other (e.g., in the same market), it could be concluded that the majority of them used a follower pricing strategy. Results of the price/quality ratio indicate a disordered state and arbitrary pricing. The application of proper milk procurement, management and sales approaches would improve, in itself, processes that take place at the critical locations, described under the headings human factors, work organization, operation, maintenance and repair, quality aspects, packaging and labeling.

Open Access: Yes

DOI: DOI not available

Y and Z generations at workplaces

Horváth Csikós Gabriella Bencsik Andrea Juhász Tímea

Publication Name: Journal of Competitiveness

Publication Date: 2016-09-01

Volume: 8

Issue: 3

Page Range: 90-106

Description:

At present, more and more researches deals with the characteristic features of generation Y and generation Z. As it is about the present and future generations, corporate success and the competitive operation are determined by the behaviour of these generations in the long-run. Researches justifies that there are significant differences between the two generations despite the similarities. These differences appear rather emphasized in the corporate environment when several questions arise at workplaces in the process of cooperation - especially in the field of knowledge-sharing and knowledge transfer-regarding the characteristics of the two generations. Last year, the authors carried out a quantitative research by questionnaires in order to reveal what the managing of these two generations mean for the managers and also what difficulties occur when the two generations cooperate with each other and with elder generations as well. The main question of the research was how to approach the new generations from the view of HR? Although the research cannot be considered representative (410 respondents participated in the survey), it can give a picture about the examined issues. The hypothesis phrased by the authors was justified according to which of the HR activities have to adapt to the requirements of the new generations upon their appearance.

Open Access: Yes

DOI: 10.7441/joc.2016.03.06

Specific heart rate values of 10-12-year-old physical education students during physical activity

Ferenc Ihász József Bognár Balázs Fügedi Pongrác Ács István Barthalos Zsolt Szakály

Publication Name: Journal of Physical Education and Sport

Publication Date: 2016-09-01

Volume: 16

Issue: 3

Page Range: 800-805

Description:

Students who participate in well-planned and structured physical education (PE) lessons engage in significantly higher levels of physical activity than children who do not. Heart rate monitoring a useful tool to help both students and teachers understand the efficiency of the physical activity. The purpose of this study was to analyze primary school children’s body compositions and heart rates when performing different types of physical activities (gymnastics, mixed activities, ball games, athletics, and games). The sample included 10-12-year-old primary school boys (N=46) and girls (N=63) from the university’s cooperating school. To estimate their body compositions, standard anthropometric techniques were used. Polar RS400 heart rate monitors were used to monitor the heart rate of each child during the main parts of different types of physical education lessons. There were no differences between the genders for the body composition or for the maximal heart rate values in the different PE content areas. The lowest heart rate was recorded during gymnastics (148 beat*min-1), and the highest values were detected during the game activities and athletics (164.60 and 163.83 beat*min-1. For the mixed activities and ball games, the heart rates ranged between 154.06 and 156.52 beat*min-1. Physical activities that result in higher heart rate values required a greater contribution and adaptation of the cardiovascular system. However, activities that elicit a lower heart rate likely focus more on skill learning and acquisition. This data can be used as a resource for physical education teachers when planning and structuring PE classes.

Open Access: Yes

DOI: 10.7752/jpes.2016.03127

Myrsinane, Premyrsinane, and Cyclomyrsinane Diterpenes from Euphorbia falcata as Potassium Ion Channel Inhibitors with Selective G Protein-Activated Inwardly Rectifying Ion Channel (GIRK) Blocking Effects

Attila Csorba Péter Orvos Gyula Pinke László Tálosi Andrea Vasas Peter Forgo Judit Hohmann

Publication Name: Journal of Natural Products

Publication Date: 2016-08-26

Volume: 79

Issue: 8

Page Range: 1990-2004

Description:

GIRK channels are activated by a large number of G protein-coupled receptors and regulate the electrical activity of neurons, cardiac atrial myocytes, and β-pancreatic cells. Abnormalities in GIRK channel function have been implicated in the pathophysiology of neuropathic pain, drug addiction, and cardiac arrhythmias. In the heart, GIRK channels are selectively expressed in the atrium, and their activation inhibits pacemaker activity, thereby slowing the heart rate. In the present study, 19 new diterpenes, falcatins A-S (1-19), and the known euphorprolitherin D (20) were isolated from Euphorbia falcata. The compounds were assayed on stable transfected HEK-hERG (Kv11.1) and HEK-GIRK1/4 (Kir3.1 and Kir3.4) cells. Blocking activity on GIRK channels was exerted by 13 compounds (61-83% at 10 μM), and, among them, five possessed low potency on the hERG channel (4-20% at 10 μM). These selective activities suggest that myrsinane-related diterpenes are potential lead compounds for the treatment of atrial fibrillation.

Open Access: Yes

DOI: 10.1021/acs.jnatprod.6b00260

Safe and secure implementation of the global platform conform infrastructure supporting the customer centric model based ecosystem

B. Benyo G. Fordos K. Kovacs B. Sodor A. Vilmos

Publication Name: Ines 2016 20th Jubilee IEEE International Conference on Intelligent Engineering Systems Proceedings

Publication Date: 2016-08-26

Volume: Unknown

Issue: Unknown

Page Range: 131-140

Description:

Global Platform (GP) as a cross industry, nonprofit association develops and publishes specifications promoting secure deployment and management of multi-Application environments of smart card technology based applications and ensuring their interoperability. The GP specifications define the business and technological processes and the associated security requirements. This publication introduces the design and development of a fully functioning smart card application management infrastructure implementing all the related GP processes and corresponding security requirements. The infrastructure supports all the phases of the application life cycle and all the partners in the ecosystem. The system is tested by several trials and certified by independent security assessment.

Open Access: Yes

DOI: 10.1109/INES.2016.7555107

The historical ecological footprint: From over-population to over-consumption

Cecília Szigeti Gergely Toth

Publication Name: Ecological Indicators

Publication Date: 2016-07-25

Volume: 60

Issue: Unknown

Page Range: 283-291

Description:

Abstract The ecological risk from over-population has been recognized since Malthus (1798). GDP growth per capita in agriculture disproved his pessimism but, since the Club of Rome and its case on Limits to Growth more recently there has been concern that there is a parallel risk from such growth in terms of ecological footprints (EF). Authors have developed a GDP/EF correlation function and calculated the ecological footprint (EF) from 10,000 B.C. till 1960, using historical statistics, with the method of backcasting (Brandes and Brooks, 2005).1 In all major indicators growth patterns have been dominating, not only since the industrial revolution, but in the known history of mankind. From data since 1961, we calculate the correlation between GDP and the ecological footprint and have been able to determine long time data series of population, GDP, biocapacity and EF. Our findings are first: the main driver of growth and environmental degradation is not population per se, but consumption patterns and levels multiplied by the number of consumers, especially in developed economies, as the I = PAT equation recognized (Ehrlich and Holdren, 1971). In fact, as we approach to today, population, which used to be the key driver to growth and environmental degradation, becomes the least important driver, especially in the last two decades. Second: change is not incremental or linear as assumed in much mainstream economics: in line with Schumpeter's bunching and swarming and it jumps and leaps asymmetrically, as in our finding of such a leap (the 7th) between the 1930s and 1970s. Third: the dominant paradigm legitimizing growth (from the late 18th century) while already challenged by many since the Club of Rome and other reports should be revisited in terms of the concept of 'fullness' in the sense that while the earth in 1776 was roughly 10 per cent full, by 2008 this figure was over 150 per cent.

Open Access: Yes

DOI: 10.1016/j.ecolind.2015.06.040

Multiresolution modeling of cavity resonators in microwave systems

András Fehér Brigita Sziová János Pipek Szilvia Nagy

Publication Name: 2016 13th International Conference on Synthesis Modeling Analysis and Simulation Methods and Applications to Circuit Design Smacd 2016

Publication Date: 2016-07-25

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

Multiresolution analysis or wavelet analysis provides a toolbox not only for signal processing, but also for synthesis of complex systems. Wavelets can be used for modeling complex parts of microwave circuits, such as cavity resonators. The differential equations describing the physical behavior of the device can be discretized using multiple resolutions simultaneously, i.e., high resolutions, where the details of the geometry demand it, and low resolutions, where the geometry is smooth. Using wavelet analysis offers the possibility of systematic and adaptive refinement, where the result is not sufficiently precise. Our method gives an approximation for the error of the solution in order to make it possible to decide, whether refinements are necessary.

Open Access: Yes

DOI: 10.1109/SMACD.2016.7520651