1,945 research outputs found

    The Michaelis-Menten-Stueckelberg Theorem

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    We study chemical reactions with complex mechanisms under two assumptions: (i) intermediates are present in small amounts (this is the quasi-steady-state hypothesis or QSS) and (ii) they are in equilibrium relations with substrates (this is the quasiequilibrium hypothesis or QE). Under these assumptions, we prove the generalized mass action law together with the basic relations between kinetic factors, which are sufficient for the positivity of the entropy production but hold even without microreversibility, when the detailed balance is not applicable. Even though QE and QSS produce useful approximations by themselves, only the combination of these assumptions can render the possibility beyond the "rarefied gas" limit or the "molecular chaos" hypotheses. We do not use any a priori form of the kinetic law for the chemical reactions and describe their equilibria by thermodynamic relations. The transformations of the intermediate compounds can be described by the Markov kinetics because of their low density ({\em low density of elementary events}). This combination of assumptions was introduced by Michaelis and Menten in 1913. In 1952, Stueckelberg used the same assumptions for the gas kinetics and produced the remarkable semi-detailed balance relations between collision rates in the Boltzmann equation that are weaker than the detailed balance conditions but are still sufficient for the Boltzmann HH-theorem to be valid. Our results are obtained within the Michaelis-Menten-Stueckelbeg conceptual framework.Comment: 54 pages, the final version; correction of a misprint in Attachment

    High frequency induction of somatic embryos and plantlet regeneration from nodal explants of Hygrophila spinosa T. Anders

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    An efficient protocol is described for the rapid in vitro plant regeneration of a medicinally important plant, Hygrophila spinosa through direct somatic embryogenesis from nodal explants excised from 4 week old aseptic seedlings. Somatic embryos differentiated directly from nodal explants on Murashige and Skoog (MS) medium supplemented with 1.0 ÏM 6- benzyladenine (BA) after 1 week of culture. The highest number (110.40 ± 3.55) of somatic embryos were recorded on MS medium supplemented with 1.0 ÏM BA and 0.5 ÏM NAA, growth regulator free half strength MS medium was found suitable for maturation and conversion of somatic embryos into complete plantlets. The well developed in vitro regenerated plantlets were successfully established in pots containing garden soil and grown in agreenhouse with 85% survival rate. The regenerants present an appearance similar to the seedlings obtained from normal seeds. The described method can be successfully employed for large scale multiplication and long term in vitro conservation of H. spinosa

    Neurosurgical electives: Operating room survival guide

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    Client Satisfaction Towards Quality of Health Services: an Assessment at Primary Healthcare of District Gujranwala

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    This survey designed to evaluate the satisfaction level and the factors that affect the patient satisfaction regarding health care delivery services with the aim to improve the services in the primary health care settings of Gujranwala. A Cross Sectional Study done on randomly selected patients attending the basic health units of Gujranwala, with more than18 years of age. Pretested structured "Liker scale questionnaire" was used for data collection. Out of total respondents, 62 (41.3%) clients were satisfied with the services provided by the basic health units of Gujranwala. The factors identified to determine patient satisfaction were accessibility of services, behavior of staff, health education, level of cleanliness, drug availability and miscellaneous services. Not a single ranked area of satisfaction noticed. Client\u27s occupation and income had significant relationship with the patient satisfaction level. Gender, age, and education of clients were not contributing factors; they not affect the client satisfaction level.Less than half clients were satisfied with the services provided by the basic health units. Management of health facilities needs to improve the services

    The role of transformational leadership on firm performance: mediating effect of corporate sustainability and moderating effect of knowledge-sharing

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    The primary purpose of the research is to investigate the mediating role of corporate sustainability in the relationship between the impacts of transformational leadership on the performance of firms. This study also aimed to investigate the moderating role of knowledge-sharing on the relationship of transformational leadership with corporate sustainability. Respondents of the study were the top management of large Chinese automobile sectors, such as Shanghai Automotive Business Corporation (Group), China FAW Group Corporation, Dongfeng Motor Co., Ltd., Beijing Automotive Group Co., Ltd., and China North Industries Group Corporation. These are the companies with the biggest market share in the automobile manufacturing industry in China. The data was gathered by using a self-administrative survey questionnaire from 198 individuals operating in different automobile industries in different sectors of China. The data were analyzed using structural equation modeling (SEM) through the Smart PLS 3.3.2 software. The results of this study revealed that transformational leadership has a positive and significant effect on the performance of the firm. Corporate sustainability has a significant positive mediating role in the association of transformational leadership and firm performance. Findings indicated that knowledge-sharing also has a positive moderating role in the association between transformational leadership and firm performance. The findings of this study contribute to the body of knowledge and show that leadership style has a significant effect on firm performance and that knowledge-sharing culture in firms is essential for better performance of the firm. Furthermore, firms may improve their performance by improving their sustainability and by creating knowledge-sharing culture. The findings are important, particularly in connection with a developed country like China. The findings have important insights for various stakeholders, i.e., government, regulatory bodies, practitioners, academia, industry, and researchers

    Does the interaction between the knowledge management process and sustainable development practices boost corporate green innovation?

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    Green innovations are being deployed in manufacturing industries to promote organisational sustainability by embracing sustainable development practices (SDPs). However, little is known about how corporate green innovation (CGI) is influenced by the knowledge management process (KMP). To fill this gap, we have developed a multidimensional framework based on the resource-based view (RBV) theory that provides a foundation for sculpturing the process by which KMP was observed to capture and sustain CGI through SDPs. Data were collected from 393 respondents of large- and medium-sized manufacturing corporations in Pakistan and analysed using partial least squares structural equation modelling (SEM) and fuzzy set qualitative comparative analysis (fsQCA). This study provides several key findings. First, KMP dimensions (acquisition, dissemination and application) significantly improve the SDPs' dimensions (environment, economic and social). Second, SDP dimensions play a significant role in achieving CGI. Third, the implementation of SDPs partially mediates the relationship between the KMP and CGI. Furthermore, the fsQCA results signify the robustness of all integrated constructs. Our results demonstrate that investing in and adopting the latest technologies and sustainable practices are not only valuable for long-term success but the soft concerns such as managing organisational knowledge are also vital in the current knowledge-based economy. Finally, in light of our findings, theoretical and managerial implications, with propositions for future studies, have been provided at the end of the paper

    Boundedness character of a max-type system of difference equations of second order

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    The boundedness character of positive solutions of the next max-type system of difference equations xn+1=max⁡{A,ynpxn−1q},yn+1=max⁡{A,xnpyn−1q},n∈N0,x_{n+1}=\max\left\{A,\frac{y_n^p}{x_{n-1}^q}\right\},\quad y_{n+1}=\max\left\{A,\frac{x_n^p}{y_{n-1}^q}\right\},\quad n\in\mathbb{N}_0, with min⁡{A,p,q}>0\min\{A, p, q\}>0, is characterized

    On a higher-order system of difference equations

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    Here we study the following system of difference equations xn = f −1 cnf(xn−2k) ∏k an + bn i=1 g(y) n−(2i−1))f(xn−2i) yn = g −1 Îłng(yn−2k) ∏k αn + ÎČn i=1 f(x) n−(2i−1))g(yn−2i) n ∈ N0, where f and g are increasing real functions such that f(0) = g(0) = 0, and coefficients an, bn, cn, αn, ÎČn, Îłn, n ∈ N0, and initial values x−i, y−i, i ∈ {1, 2,..., 2k} are real numbers. We show that the system is solvable in closed form, and study asymptotic behavior of its solutions

    Numerical Evaluation of Microwave Thermal Ablation to Treat Small Adrenocortical Masses

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    In this paper microwave thermal ablation is numerically evaluated in the context of a treatment for Conn’s Syndrome. This condition is caused by a benign shallow tumour in the cortex of adrenal gland. The modelling and design of microwave applicator to deliver thermal ablation to the adrenal gland requires accurate tissue characterisation. Measuring the dielectric properties of the constituent tissues in the adrenal gland, i.e. cortex and medulla, enables more accurate numerical modelling for electromagnetic and thermal simulations. This study presents an anatomically and dielectrically realistic numerical model of the adrenal gland, and investigates the feasibility of applying controlled heating to small targets in the adrenal cortex. In addition, the use of dielectric contrast between the fat and the cortex of the adrenal gland to focus the thermal energy in the gland has also been studied. Being conscious of limitations of numerical simulation of complex multiphysics problems like the microwave ablative treatment, calculated results provide a preliminary description of the electromagnetic and thermal phenomena involved

    Convective Heat Transfer Enhancement for Electronic Device Applications using Patterned MWCNTs Structures

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    This article reports on the heat transfer characteristics of columnar Vertically Aligned Multiwall Carbon Nanotubes (VA-MWCNTs) grown on a patterned Si surface. In the first part, we describe the procedure for patterning the silicon (Si) surface and the growth of MWCNTS on these patterned surfaces. The diameter of MWCNTs grown by Chemical Vapor Deposition (CVD) technique was in the range of 30-80 nm. In the second part structures mimicking macroscopic finned heat sinks are used for enhancing forced convective heat transfer on a silicon substrate. Convective heat transfer coefficient has been experimentally measured for silicon substrates with and without MWCNT-based fins on it. The configuration with MWCNTs based fins shows an enhancement in convective heat transfer of 40% and 20%, as maximum and average value respectively, compared to the bare silicon. Experiments have been carried out in a wind tunnel with air as coolant in fully turbulent regime. These encouraging results and the possibility of growing structures directly on silicon can be regarded as a first step
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