Abstract: Chitosan is a derivative of chitin, a compound usually
isolated from the shells of some crustaceans such as crab, lobster and
shrimp. It has biocompatible, biodegradable, and antimicrobial
properties. To use these properties of chitosan in biomedical fields,
chitosan films (1%, 2%, 3% and 4%) were prepared by using l%
lactic acid as solvent. The effects of chitosan films on tensile
strength, elongation at break, degree of swelling, thickness,
morphology, allergic and irritation reactions and antibacterial
property were evaluated. Staphylococcus aureus and Escherichia coli
were used as tested microorganisms. In vivo wound healing activities
of chitosan films were investigated using mice model. As results,
Chitosan films have similar appearance and good swelling properties
and 4% chitosan film showed the better swelling activity and the
greatest elongation ratio than the other chitosan films. They also
showed their good activity of wound healing in mice model.
Moreover, the results showed that the films did not produce any
unwilling symptoms (allergy or irritation). In conclusion, it is evident
that the chitosan film has the potentiality to use as wound healing
biofilms in the biomedical fields.
Abstract: Introduction: Pegylated Interferon and Ribavirin combination is standard of care in the management of chronic HCV infected patients. Efficacy of the therapy is judged by the ability to achieve biochemical and virological response as judged by RVR, EVR, ETR and SVR.Objective: To evaluate the efficacy of newly marketed biosimilar Pegylated Interferon Alpha 40KD (Peg INF) in chronic HCV patients. Materials and methods: This was observational, prospective multicentre study to evaluate the ability of biosimilar pegylated interferon alfa 2a (40KD) along with Ribavirin (weight based) to achieve SVR. The enrolled patients were separated into Naïve (A), Relapsers (B) and Non Responders(C) based on the previous history of interferon exposure and its response. The RGT was followed on ALT and RVR, EVR, ETR and SVR.Results:As per protocol analysis estimated SVR for three groups is 86.6% for naïve, 89.4% for relapsers and 52.4% for non-responders to standard interferon. Conclusion: It is concluded that Bio-similar pegylated interferon alfa-2a (40kD) along with Ribavirin has good anti-viral efficacy in Naïve, Relapsers and Non-responders to standard IFN of chronic HCV infected patients requiring treatment.
Abstract: Worldwide interests for the renewable energy are increasing due to environmental and climate changes from traditional petroleum related energy sources. To account for these social needs, ligneous biomass energy is considered as one of the environmentally friend energy solutions. The wood torrefaction process is a feasible method to improve the properties of the biomass fuel and makes the wood have low moisture, lower smoke emission and increased heating value. In this work, therefore, the moisture evaporation model which largely affects energy efficiency of ligneous biomass through moisture contents and heating value relative to its weight is studied with numerical modeling approach by analyzing the effects of torrefaction furnace temperature. The results show that the temperature and moisture fraction of wood decrease by increasing the furnace temperature. When the torrefaction temperature is lower than 423K, there were little changes of the moisture fraction in the wood. Also, it can be found that charcoal is produced more slowly when the torrefaction temperature is lower than 573K.
Abstract: Transesterification reactions free of catalyst between
roasted chicken fat with methanol were carried out in a batch reactor
in order to produce biodiesel to temperatures from 120°C to 140°C.
Parameters related to the transesterification reactions, including
temperature, time and the molar ratio of chicken fat to methanol also
investigated. The maximum yield of the reaction was of 98% under
conditions of 140°C, 4 h of reaction time and a molar ratio of chicken
fat to methanol of 1:31. The biodiesel thus obtained exhibited a
viscosity of 6.3 mm2/s and a density of 895.9 kg/m3. The results
showed this process can be right choice to produce biodiesel since
this process does not use any catalyst. Therefore, the steps of
neutralization and washing are avoided, indispensables in the case of
the alkaline catalysis.
Abstract: The gap between the selection of risk-reduction options in the railway industry and the task of their effective implementation results in compromised safety and substantial losses. An effective risk management must necessarily integrate the evaluation phases with the implementation phase. This paper proposes an essential categorisation of risk reduction measures that best addresses a standard railway industry portfolio. By categorising the risk reduction options into design, operational, procedural and technical options, it is guaranteed that the efforts of the implementation facilitators (people, processes and supporting systems) are systematically harmonised. The classification is based on an integration of fundamental principles of risk reduction in the railway industry with the systems engineering approach.
This paper argues that the use of a similar classification approach is an attribute of organisations possessing a superior level of risk-reduction readiness. The integration of the proposed rational classification structure provides a solid ground for effective risk reduction.
Abstract: There has been studied the distribution character of potato stem nematode (Ditylenchus destructor Thorne, 1945) on the potato fields in four municipalities (Tsalka, Bolnisi, Marneuli, Gardabani) of Kvemo Kartli (Eastern Georgia).
As a result of scientific research there is stated the extensiveness of pathogens invasion, accompanying composition of fauna species, environmental groups of populations and quantity.
During the research process in the studied ecosystems there were registered 160 forms of free-living and Phyto-parasitic nematodes, from which 118 forms are determined as species and 42 as genus.
It was found that in almost the entire studied ecosystem there is dominated pathogenic nematodes Ditylenchus destructor. The large number of exemplars (almost uncountable) was found in tubers material of Bolnisi and Gardabani.
Abstract: The heat and mass transfer was investigated during the falling rate period of spray drying of a slurry droplet. The effect of the porosity of crust layer formed from primary particles during liquid evaporation was studied numerically using the developed mathematical model which takes into account the heat and mass transfer in the core and crust regions, the movement of the evaporation interface, and the external heat and mass transfer between the drying air and the droplet surface. It was confirmed that the heat transfer through the crust layer was more intense in the case of the dense droplet than the loose one due to the enhanced thermal conduction resulting in the higher average droplet temperature. The mass transfer was facilitated in the crust layer of loose droplet owing to the large pore space available for diffusion of water vapor from the evaporation interface to the outer droplet surface. The longer drying time is required for the droplet of high porosity to reach the final moisture content than that for the dense one due to the larger amount of water to be evaporated during the falling rate.
Abstract: The concept of adaptive shape parameters (ASP) has been presented for solution of incompressible Navier Strokes equations using mesh-free local Radial Basis Functions (RBF). The aim is to avoid ill-conditioning of coefficient matrices of RBF weights and inaccuracies in RBF interpolation resulting from non-optimized shape of basis functions for the cases where data points (or nodes) are not distributed uniformly throughout the domain. Unlike conventional approaches which assume globally similar values of RBF shape parameters, the presented ASP technique suggests that shape parameter be calculated exclusively for each data point (or node) based on the distribution of data points within its own influence domain. This will ensure interpolation accuracy while still maintaining well conditioned system of equations for RBF weights. Performance and accuracy of ASP technique has been tested by evaluating derivatives and laplacian of a known function using RBF in Finite difference mode (RBFFD), with and without the use of adaptivity in shape parameters. Application of adaptive shape parameters (ASP) for solution of incompressible Navier Strokes equations has been presented by solving lid driven cavity flow problem on mesh-free domain using RBF-FD. The results have been compared for fixed and adaptive shape parameters. Improved accuracy has been achieved with the use of ASP in RBF-FD especially at regions where larger gradients of field variables exist.
Abstract: We constructed an atomic structure model for a PAN-based carbon fiber containing amorphous structures using molecular dynamics methods. It was found that basic physical properties such as crystallinity, Young’s modulus, and thermal conductivity of our model were nearly identical to those of real carbon fibers. We then obtained the tensile strength of a carbon fiber, which has no macro defects. We finally determined that the limitation of the tensile strength was 19 GPa.
Abstract: Travel Demands influence micro-level traffic behavior,
furthermore traffic states. In order to evaluate the effect of travel
demands on traffic states, this paper introduces the Demand-
Motivation-Behaviors (DMB) micro traffic behavior analysis model
which denotes that vehicles behaviors are determines by motivations
that relies on traffic demands from the perspective of behavior
science. For vehicles, there are two kinds of travel demands: reaching
travel destinations from orientations and meeting expectations of
travel speed. To satisfy travel demands, the micro traffic behaviors are
delivered such as car following behavior, optional and mandatory lane
changing behaviors. Especially, mandatory lane changing behaviors
depending on travel demands take strong impact on traffic states.
In this paper, we define the DMB-based cellular automate traffic
simulation model to evaluate the effect of travel demands on traffic
states under the different δ values that reflect the ratio of mandatory
lane-change vehicles.
Abstract: In this paper, by constructing a special cone and using
fixed point theorem and fixed point index theorem of cone, we get the
existence of positive solution for a class of singular eigenvalue value
problems with p-Laplace operator, which improved and generalized
the result of related paper.
Abstract: Axial compression tests are performed on circular tubes made of Aluminum EN AW 6060 (AlMgSi0.5 alloy) in T66 state. All the received tubes have the uniform outer diameter of 40mm and thickness of 1.5mm. Two different lengths 100mm and 200mm are used in the analysis. After performing compression tests on the uniform tube, important crashworthy parameters like peak force, average force, crush efficiency and energy absorption are measured. The present paper has given importance to increase the percentage of crush efficiency without decreasing the value energy absorption of a tube, so a circumferential notch was introduced on the top section of the tube. The effects of position and cut-out lengths of a circumferential notch on the crush efficiency are well explained with relative deformation modes and force-displacement curves. The numerical simulations were carried on the software tool ANSYS/LS-DYNA. It is seen that the numerical results are reasonably good in agreement with the experimental results.
Abstract: Discrete search path planning in time-constrained uncertain environment relying upon imperfect sensors is known to be hard, and current problem-solving techniques proposed so far to compute near real-time efficient path plans are mainly bounded to provide a few move solutions. A new information-theoretic –based open-loop decision model explicitly incorporating false alarm sensor readings, to solve a single agent military logistics search-and-delivery path planning problem with anticipated feedback is presented. The decision model consists in minimizing expected entropy considering anticipated possible observation outcomes over a given time horizon. The model captures uncertainty associated with observation events for all possible scenarios. Entropy represents a measure of uncertainty about the searched target location. Feedback information resulting from possible sensor observations outcomes along the projected path plan is exploited to update anticipated unit target occupancy beliefs. For the first time, a compact belief update formulation is generalized to explicitly include false positive observation events that may occur during plan execution. A novel genetic algorithm is then proposed to efficiently solve search path planning, providing near-optimal solutions for practical realistic problem instances. Given the run-time performance of the algorithm, natural extension to a closed-loop environment to progressively integrate real visit outcomes on a rolling time horizon can be easily envisioned. Computational results show the value of the approach in comparison to alternate heuristics.
Abstract: In this article, we propose a new approximate procedure
based on He’s variational iteration method for solving nonlinear
hyperbolic equations. We introduce two transformations q = ut and
σ = ux and formulate a first-order system of equations. We can
obtain the approximation solution for the scalar unknown u, time
derivative q = ut and space derivative σ = ux, simultaneously.
Finally, some examples are provided to illustrate the effectiveness of
our method.
Abstract: In this paper, by constructing a special operator and using fixed point index theorem of cone, we get the sufficient conditions for symmetric positive solution of a class of nonlinear singular boundary value problems with p-Laplace operator, which improved and generalized the result of related paper.
Abstract: The aim of this study is to describe the differences between women and men in the phenomena of feeling of knowing/know (FOK), tip of the tongue (TOT), and verbal fluency. Two studies are presented. The first included a group of 60 participants and focused on the analysis of FOK and TOT in men and women. The second study described the performance of 302 participants in verbal fluency tasks. Both studies showed that sex is not a significant predictor of linguistic abilities. Rather, the main factors influencing one’s linguistic ability were Vocabulary and education. This study enriches the knowledge on mechanisms of memory and verbal production.
Abstract: In this work we study the thermodynamic behavior of some ventilated facades under summer operating conditions in Southern Spain. Under these climatic conditions, indoor comfort implies a high energetic demand due to high temperatures that usually are reached in this season in the considered geographical area.
The aim of this work is to determine if during summer operating conditions in Southern Spain, ventilated façades provide some energy saving compared to the non-ventilated façades and to deduce their behavior patterns in terms of energy efficiency.
The modelization of the air flow in the channel has been performed by using Navier-Stokes equations for thermodynamic flows. Numerical simulations have been carried out with a 2D Finite Element approach.
This way, we analyze the behavior of ventilated façades under different weather conditions as variable wind, variable temperature and different levels of solar irradiation.
CFD computations show the combined effect of the shading of the external wall and the ventilation by the natural convection into the air gap achieve a reduction of the heat load during the summer period. This reduction has been evaluated by comparing the thermodynamic performances of two ventilated and two unventilated façades with the same geometry and thermophysical characteristics.
Abstract: Simultaneous measurements of the curves for wear versus distance, wear rate versus distance, and coefficient of friction versus distance were performed in situ to distinguish the transition from severe running-in wear to mild wear. The effects of the initial surface roughness on the severe running-in wear volume were investigated. Disk-on-plate friction and wear tests were carried out with SUS304 austenitic stainless steel in contact with itself under repeated dry sliding conditions at room temperature. The wear volume was dependent on the initial surface roughness. The wear volume when the initial surfaces on the plate and disk had dissimilar roughness was lower than that when these surfaces had similar roughness. For the dissimilar roughness, the wear volume decreased with decreasing initial surface roughness and reached a minimum; it stayed nearly constant as the roughness was less than the mean size of the oxide particles.
Abstract: We study a Dirichlet boundary value problem for Lane-Emden equation involving two fractional orders. Lane-Emden equation has been widely used to describe a variety of phenomena in physics and astrophysics, including aspects of stellar structure, the thermal history of a spherical cloud of gas, isothermal gas spheres,and thermionic currents. However, ordinary Lane-Emden equation does not provide the correct description of the dynamics for systems in complex media. In order to overcome this problem and describe dynamical processes in a fractalmedium, numerous generalizations of Lane-Emden equation have been proposed. One such generalization replaces the ordinary derivative by a fractional derivative in the Lane-Emden equation. This gives rise to the fractional Lane-Emden equation with a single index. Recently, a new type of Lane-Emden equation with two different fractional orders has been introduced which provides a more flexible model for fractal processes as compared with the usual one characterized by a single index. The contraction mapping principle and Krasnoselskiis fixed point theorem are applied to prove the existence of solutions of the problem in a Banach space. Ulam-Hyers stability for iterative Cauchy fractional differential equation is defined and studied.
Abstract: The effect of internal heat generation is applied to the Rayleigh-Benard convection in a horizontal micropolar fluid layer. The bounding surfaces of the liquids are considered to be rigid-free, rigid-rigid and free-free with the combination of isothermal on the spin-vanishing boundaries. A linear stability analysis is used and the Galerkin method is employed to find the critical stability parameters numerically. It is shown that the critical Rayleigh number decreases as the value of internal heat generation increase and hence destabilize the system.