Fractal and Multifractal Analyses of the Porosity Degree of Ceramics Used in Biomedicine

2020 ◽  
Vol 12 (4) ◽  
pp. 450-456
Author(s):  
Wiktoria Sapota ◽  
Patrycja Szczepanik ◽  
Sebastian Stach ◽  
Zygmunt Wróbel
Keyword(s):  
Fractal Dimension ◽  
Cellular Response ◽  
Quantitative Description ◽  
Ceramic Coatings ◽  
Quantitative Fractography ◽  
Porous Surfaces ◽  
Scale Properties ◽  
New Generation ◽  
The Impact ◽  
Area Development

Designing a new generation of biomaterials is based on the assumption that the appropriate chemical composition of a material, the chemical state of its surface and the surface structure in nanoand micrometer scales are the elements which selected in a planned way decide on the type of cellular response to the material. The use of quantitative fractography enables a quantitative description of the surface. The parameter most frequently used in surface stereometry is the area development coefficient Sdr. Attempts are being made to use other tools for determining additional parameters. One of them may be fractal analysis, in which fractal dimension D is the measure of surface complexity. For the purposes of the study, comparative fractal and multifractal analyses of images showing porous surfaces of Al2O3 ceramic coatings were performed. The analyses were carried out for three lenses, namely 20×, 50× and 100×, and the impact of magnification (scale properties) on the obtained results was examined.

Overcoming stereotypes of renewable energy

2019 ◽  
pp. 124-136
Author(s):  
Victor D. Gazman
Keyword(s):  
Renewable Energy ◽  
Empirical Analysis ◽  
Energy Generation ◽  
New Paradigm ◽  
Financial Instrument ◽  
Promising Direction ◽  
Investment Projects ◽  
Power Stations ◽  
New Generation ◽  
The Impact

The article considers prerequisites for the formation of a new paradigm in the energy sector. The factors that may affect the imminent change of leadership among the energy generation are analyzed. The variability of the projects of creation and functioning of power stations is examined. The focus is made on problematic aspects of the new generation, especially, storage and supply of energy, achieving a system of parity that ensures balance in pricing generations. The author substantiates the principles of forming system of parities arising when comparing traditional and new generations. The article presents the results of an empirical analysis of the 215 projects for the construction of facilities for renewable energy. The significance and direction of the impact of these factors on the growth in investment volumes of transactions are determined. The author considers leasing as an effective financial instrument for overcoming stereotypes of renewable energy and as a promising direction for accelerated implementation of investment projects.

scholarly journals The Impact of Initial Conditions in N-Body Simulations of Debris Discs

2015 ◽  
Vol 32 ◽  
Author(s):  
E. Thilliez ◽  
S. T. Maddison
Keyword(s):  
Numerical Simulations ◽  
Initial Conditions ◽  
Parent Body ◽  
Dust Trapping ◽  
Physical Context ◽  
Disc Width ◽  
Wide Range ◽  
Belt Width ◽  
New Generation ◽  
The Impact

AbstractNumerical simulations are a crucial tool to understand the relationship between debris discs and planetary companions. As debris disc observations are now reaching unprecedented levels of precision over a wide range of wavelengths, an appropriate level of accuracy and consistency is required in numerical simulations to confidently interpret this new generation of observations. However, simulations throughout the literature have been conducted with various initial conditions often with little or no justification. In this paper, we aim to study the dependence on the initial conditions of N-body simulations modelling the interaction between a massive and eccentric planet on an exterior debris disc. To achieve this, we first classify three broad approaches used in the literature and provide some physical context for when each category should be used. We then run a series of N-body simulations, that include radiation forces acting on small grains, with varying initial conditions across the three categories. We test the influence of the initial parent body belt width, eccentricity, and alignment with the planet on the resulting debris disc structure and compare the final peak emission location, disc width and offset of synthetic disc images produced with a radiative transfer code. We also track the evolution of the forced eccentricity of the dust grains induced by the planet, as well as resonance dust trapping. We find that an initially broad parent body belt always results in a broader debris disc than an initially narrow parent body belt. While simulations with a parent body belt with low initial eccentricity (e ~ 0) and high initial eccentricity (0 < e < 0.3) resulted in similar broad discs, we find that purely secular forced initial conditions, where the initial disc eccentricity is set to the forced value and the disc is aligned with the planet, always result in a narrower disc. We conclude that broad debris discs can be modelled by using either a dynamically cold or dynamically warm parent belt, while in contrast eccentric narrow debris rings are reproduced using a secularly forced parent body belt.

scholarly journals Measuring Key Quality Indicators in Cloud Gaming: Framework and Assessment Over Wireless Networks

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1387
Author(s):  
Oswaldo Sebastian Peñaherrera-Pulla ◽  
Carlos Baena ◽  
Sergio Fortes ◽  
Eduardo Baena ◽  
Raquel Barco
Keyword(s):  
Communication Networks ◽  
Mobile Networks ◽  
Video Game ◽  
Know How ◽  
Fifth Generation ◽  
New Generation ◽  
Graphics Rendering ◽  
The Impact

Cloud Gaming is a cutting-edge paradigm in the video game provision where the graphics rendering and logic are computed in the cloud. This allows a user’s thin client systems with much more limited capabilities to offer a comparable experience with traditional local and online gaming but using reduced hardware requirements. In contrast, this approach stresses the communication networks between the client and the cloud. In this context, it is necessary to know how to configure the network in order to provide service with the best quality. To that end, the present work defines a novel framework for Cloud Gaming performance evaluation. This system is implemented in a real testbed and evaluates the Cloud Gaming approach for different transport networks (Ethernet, WiFi, and LTE (Long Term Evolution)) and scenarios, automating the acquisition of the gaming metrics. From this, the impact on the overall gaming experience is analyzed identifying the main parameters involved in its performance. Hence, the future lines for Cloud Gaming QoE-based (Quality of Experience) optimization are established, this way being of configuration, a trendy paradigm in the new-generation networks, such as 4G and 5G (Fourth and Fifth Generation of Mobile Networks).

scholarly journals Impact of Carcinogenic Chromium on the Cellular Response to Proteotoxic Stress

2019 ◽  
Vol 20 (19) ◽  
pp. 4901 ◽  
Author(s):  
Leonardo M. R. Ferreira ◽  
Teresa Cunha-Oliveira ◽  
Margarida C. Sobral ◽  
Patrícia L. Abreu ◽  
Maria Carmen Alpoim ◽  
...  
Keyword(s):  
Stress Response ◽  
Health Effects ◽  
Cellular Response ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Chemical Properties ◽  
Adverse Health Effects ◽  
Proteotoxic Stress ◽  
Adverse Health ◽  
The Impact

Worldwide, several million workers are employed in the various chromium (Cr) industries. These workers may suffer from a variety of adverse health effects produced by dusts, mists and fumes containing Cr in the hexavalent oxidation state, Cr(VI). Of major importance, occupational exposure to Cr(VI) compounds has been firmly associated with the development of lung cancer. Counterintuitively, Cr(VI) is mostly unreactive towards most biomolecules, including nucleic acids. However, its intracellular reduction produces several species that react extensively with biomolecules. The diversity and chemical versatility of these species add great complexity to the study of the molecular mechanisms underlying Cr(VI) toxicity and carcinogenicity. As a consequence, these mechanisms are still poorly understood, in spite of intensive research efforts. Here, we discuss the impact of Cr(VI) on the stress response—an intricate cellular system against proteotoxic stress which is increasingly viewed as playing a critical role in carcinogenesis. This discussion is preceded by information regarding applications, chemical properties and adverse health effects of Cr(VI). A summary of our current understanding of cancer initiation, promotion and progression is also provided, followed by a brief description of the stress response and its links to cancer and by an overview of potential molecular mechanisms of Cr(VI) carcinogenicity.

“The New Generation”: Mental Hygiene and the Portrayals of Children by the National Film Board of Canada, 1946–1967

2003 ◽  
Vol 43 (4) ◽  
pp. 540-570 ◽  
Author(s):  
Brian J. Low
Keyword(s):  
Social Relations ◽  
Mental Hygiene ◽  
Social Attitudes ◽  
Child Rearing ◽  
Mass Psychology ◽  
National Film Board ◽  
The Mind ◽  
Schooling Practices ◽  
New Generation ◽  
The Impact

That is the achievement of the psychologists. In our own society they are very kind, and do everything for our own good. The tales of what they do elsewhere are rather terrifying.—Hilda NeatbySo Little for the Mind (1953)Documenting the impact of the mental hygiene movement has been problematical for historians. The hygienists operated in the realm of mass psychology and social relations, within the “mentalities” of children—particularly of the postwar generation—who have left little observable evidence of changing social attitudes and relationships resulting from changes to mass child-rearing and schooling practices. The influence of the movement upon parenting literature and curricular documents may be readily observed in postwar baby books, magazines, newspapers, radio scripts, and films, as well as in the changing language of educational theorists and practitioners. But as to seeing the actual effects of this material upon any society, documentary evidence has remained elusive.

Testing for long memory in the presence of a general trend

2001 ◽  
Vol 38 (04) ◽  
pp. 1033-1054 ◽  
Author(s):  
Liudas Giraitis ◽  
Piotr Kokoszka ◽  
Remigijus Leipus
Keyword(s):  
Long Memory ◽  
Change Point ◽  
General Trend ◽  
Quantitative Description ◽  
Stationary Sequence ◽  
Change Points ◽  
Asymptotic Size ◽  
Short Memory ◽  
The Impact ◽  
Do So

The paper studies the impact of a broadly understood trend, which includes a change point in mean and monotonic trends studied by Bhattacharyaet al.(1983), on the asymptotic behaviour of a class of tests designed to detect long memory in a stationary sequence. Our results pertain to a family of tests which are similar to Lo's (1991) modifiedR/Stest. We show that both long memory and nonstationarity (presence of trend or change points) can lead to rejection of the null hypothesis of short memory, so that further testing is needed to discriminate between long memory and some forms of nonstationarity. We provide quantitative description of trends which do or do not fool theR/S-type long memory tests. We show, in particular, that a shift in mean of a magnitude larger thanN-½, whereNis the sample size, affects the asymptotic size of the tests, whereas smaller shifts do not do so.

scholarly journals Green Preparation, Spheroidal, and Superior Property of Nano-1,3,5,7-Tetranittro-1,3,5,7-Tetrazocane

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Xinlei Jia ◽  
Jingyu Wang ◽  
Conghua Hou ◽  
Yingxin Tan
Keyword(s):  
Activation Energy ◽  
Particle Size ◽  
Fractal Dimension ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fractal Theory ◽  
Crystal Form ◽  
Decomposition Temperature ◽  
Scanning Calorimetry ◽  
The Impact

Herein, a green process for preparing nano-HMX, mechanical demulsification shearing (MDS) technology, was developed. Nano-HMX was successfully fabricated via MDS technology without using any chemical reagents, and the fabrication mechanism was proposed. Based on the “fractal theory,” the optimal shearing time for mechanical emulsification was deduced by calculating the fractal dimension of the particle size distribution. The as-prepared nano-HMX was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). And the impact sensitivities of HMX particles were contrastively investigated. The raw HMX had a lower fractal dimension of 1.9273. The ideal shearing time was 7 h. The resultant nano-HMX possessed a particle size distribution ranging from 203.3 nm to 509.1 nm as compared to raw HMX. Nano-HMX particles were dense spherical, maintaining β-HMX crystal form. In addition, they had much lower impact sensitivity. However, the apparent activation energy as well as thermal decomposition temperature of nano-HMX particles was decreased, attributing to the reduced probability for hotspot generation. Especially when the shearing time was 7 h, the activation energy was markedly decreased.

scholarly journals China's Rural Migrant Workers, the State, and Labor Politics

2017 ◽  
Author(s):  
Jenny Chan ◽  
Mark Selden
Keyword(s):  
Migrant Workers ◽  
The State ◽  
Labor Politics ◽  
Rural Migrant ◽  
Industrial Labor ◽  
Class Power ◽  
The Individual ◽  
New Generation ◽  
The Impact ◽  
Rural Migrant Workers

The proletarianization of rural migrants is distinctive to contemporary China's development model, in which the state has fostered the growth of a “semi-proletariat” numbering more than 200 million to fuel labor-intensive industries and urbanization. Drawing on fieldwork in Guangdong and Sichuan provinces between 2010 and 2014, supplemented with scholarly studies and government surveys, the authors analyze the precarity and the individual and collective struggles of a new generation of rural migrant workers. They present an analysis of high and growing levels of labor conflict at a time when the previous domination of state enterprises has given way to the predominance of migrant workers as the core of an expanding industrial labor force. In particular, the authors assess the significance of the growing number of legal and extra-legal actions taken by workers within a framework that highlights the deep contradictions among labor, capital, and the Chinese state. They also discuss the impact of demographic changes and geographic shifts of population and production on the growth of working-class power in the workplace and the marketplace.

Sign in / Sign up

Export Citation Format

Share Document