Search results for: partial penetration
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1791

Search results for: partial penetration

921 Near-Infrared Optogenetic Manipulation of a Channelrhodopsin via Upconverting Nanoparticles

Authors: Kanchan Yadav, Ai-Chuan Chou, Rajesh Kumar Ulaganathan, Hua-De Gao, Hsien-Ming Lee, Chien-Yuan Pan, Yit-Tsong Chen

Abstract:

Optogenetics is an innovative technology now widely adopted by researchers in different fields of the biological sciences. However, due to the weak tissue penetration capability of the short wavelengths used to activate light-sensitive proteins, an invasive light guide has been used in animal studies for photoexcitation of target tissues. Upconverting nanoparticles (UCNPs), which transform near-infrared (NIR) light to short-wavelength emissions, can help address this issue. To improve optogenetic performance, we enhance the target selectivity for optogenetic controls by specifically conjugating the UCNPs with light-sensitive proteins at a molecular level, which shortens the distance as well as enhances the efficiency of energy transfer. We tagged V5 and Lumio epitopes to the extracellular N-terminal of channelrhodopsin-2 with an mCherry conjugated at the intracellular C-terminal (VL-ChR2m) and then bound NeutrAvidin-functionalized UCNPs (NAv-UCNPs) to the VL-ChR2m via a biotinylated antibody against V5 (bV5-Ab). We observed an apparent energy transfer from the excited UCNP (donor) to the bound VL-ChR2m (receptor) by measuring emission-intensity changes at the donor-receptor complex. The successful patch-clamp electrophysiological test and an intracellular Ca2+ elevation observed in the designed UCNP-ChR2 system under optogenetic manipulation confirmed the practical employment of UCNP-assisted NIR-optogenetic functionality. This work represents a significant step toward improving therapeutic optogenetics.

Keywords: Channelrhodopsin-2, near infrared, optogenetics, upconverting nanoparticles

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920 Transformational Leadership and Departmental Performance: The Intervening Role of Internal Communication and Citizen/Customer Participation

Authors: Derrick Boakye Boadu, Zahra Fakhri

Abstract:

Transformational leaders are the catalyst of change and focus more importantly on members or followers. Involvement of transformational leadership style in organizational structures can provide interesting nuances to the implementation and enhancement of citizen and customer participation mechanisms in an organization regardless of the time consuming, cost, and delaying process of analyzing the feedback of workers and citizens/customers which stifles good outcome of organization’s department performance. It posits that transformational leadership has a positive direct effect on organization-departmental performance and the intervening role of citizen and customer participation and internal communication. Using the NASP-IV 2007 data, the article finds support for the five hypotheses in a structural equation model, and the findings show that transformational leadership does have a direct impact on organizational-departmental performance a partial mediation effect of the relationship through the role of internal communication and citizen and customer participation.  

Keywords: transformational leaders, departmental performance, internal communication, citizen/customer participation

Procedia PDF Downloads 111
919 Sustainable Biogas Upgrading: Characterization of Adsorption Properties of Tuff

Authors: Emanuele Bonamente, Andrea Aquino, Franco Cotana

Abstract:

This paper presents experimental results from the analysis of Tuff for CO2 and H2S removal from biogas. Synthetic zeolites, commonly used for biogas upgrading, are characterized by excellent performance in terms of carbon dioxide adsorption, however, cost and environmental footprint represent a negative contribute to their sustainability. Natural zeolites contained in Tuff, a totally inexpensive byproduct of the construction industry, show very interesting selective adsorption properties, associated with its availability in regions, as central Italy, where biogas production from small scale plants is rapidly increasing. An in-house experimental device was assembled to measure the adsorption capacity of Tuff as a function of partial CO2 pressure for different temperatures (i.e. adsorption isotherms). Results show performances as high as 66% with respect to commercial zeolites (13X). A sensitivity analysis of different regeneration processes is also presented. A comparative analysis of natural and synthetic zeolites was finally performed using biogas samples obtained from different types of feedstock and characterized by varying CO2 and H2S content.

Keywords: biogas upgrading, CO2 adsorption, sustainable energy, tuff

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918 Streptavidin-Biotin Attachment on Modified Silicon Nanowires

Authors: Shalini Singh, Sanjay K. Srivastava, Govind, Mukhtar. A. Khan, P. K. Singh

Abstract:

Nanotechnology is revolutionizing the development of biosensors. Nanomaterials and nanofabrication technologies are increasingly being used to design novel biosensors. Sensitivity and other attributes of biosensors can be improved by using nanomaterials with unique chemical, physical, and mechanical properties in their construction. Silicon is a promising biomaterial that is non-toxic and biodegradable and can be exploited in chemical and biological sensing. Present study demonstrated the streptavidin–biotin interaction on silicon surfaces with different topographies such as flat and nanostructured silicon (nanowires) surfaces. Silicon nanowires with wide range of surface to volume ratio were prepared by electrochemical etching of silicon wafer. The large specific surface of silicon nanowires can be chemically modified to link different molecular probes (DNA strands, enzymes, proteins and so on), which recognize the target analytes, in order to enhance the selectivity and specificity of the sensor device. The interaction of streptavidin with biotin was carried out on 3-aminopropyltriethoxysilane (APTS) functionalized silicon surfaces. Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) studies have been performed to characterize the surface characteristics to ensure the protein attachment. Silicon nanowires showed the enhance protein attachment, as compared to flat silicon surface due to its large surface area and good molecular penetration to its surface. The methodology developed herein could be generalized to a wide range of protein-ligand interactions, since it is relatively easy to conjugate biotin with diverse biomolecules such as antibodies, enzymes, peptides, and nucleotides.

Keywords: FTIR, silicon nanowires, streptavidin-biotin, XPS

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917 Nutritive Advantage of Mealworm (Tenebrio molitor) in the Diet of White Shrimp (Litopenaeus vannamei)

Authors: Tae-ho Chung, Chul Park, Gi-wook Shin, Joo-min Kim, Seong-hyun Kim, Namjung Kim

Abstract:

Mealworm (Tenebrio molitor) was evaluated to investigate the effect of partial or total replacement of fish meal in diets for white shrimp, Litopenaeus vannamei. Experimental groups of shrimp with average initial body weight (2.43 ± 0.54 g) were fed each with 4 isonitrogeneous (38% crude protein) diets formulated to include 0, 25, 50 and 100% (diets 1 to 4, respectively) of fish meal substituted with mealworm. After eight weeks of feeding trials, shrimp fed with diet 3 and 4 revealed the highest values for live weight gain(8.01 ± 2.51 and 7.93 ± 1.12), specific growth rates (2.70 ± 1.12 and 2.59 ± 0.51) as well as better feed conversion ratio (2.69 ± 0.09 and 2.72 ± 0.19) compared to the control group with statistically significant manner (p<0.05). Survival range was 98% in all the treatments. An increase in weight gain and other growth associated parameters was observed with higher replacement. These results clearly indicate that 50% and 100% of fish meal protein in shrimp diet can be replaced by mealworm not only without any adverse effect but also the effect of promoting growth performance.

Keywords: mealworm, Litopenaeus vannamei, Tenebrio molitor, white shrimp

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916 Formulation and Physico-Mechanical Characterization of a Self-Compacting Concrete Containing Seashells as an Addition Material

Authors: Brahim Safi, Mohammed Saidi, A. Benmounah, Jozef Mitterpach

Abstract:

The aim of this work is to study the rheological and physico-mechanical properties of a self-compacting concrete elaborated with sea shells as an addition cementitious (total replacement of limestone fillers) and sand (partial and total substitution fine aggregate). Also, this present study is registered in the context of sustainable development by using this waste type which caused environmental problems. After preparation the crushed shells (obtaining fine aggregate) and finely crushed shells (obtaining end powder), concretes were manufactured using these two products. Rheological characterization tests (fluidity, filling capacity and segregation) and physico-mechanical properties (density and strength) were carried on these concretes. The results obtained show that it can be used as fin addition (by total replacement of limestone) or also used as sand by total substitution of natural sand.

Keywords: seashells, limestone, sand, self-compacting concrete, fluidity, compressive strength, flexural strength

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915 Development of Biosurfactant-Based Adjuvant for Enhancing Biocontrol Efficiency

Authors: Kanyarat Sikhao, Nichakorn Khondee

Abstract:

Adjuvant is commonly mixed with agricultural spray solution during foliar application to improve the performance of microbial-based biological control, including better spreading, absorption, and penetration on a plant leaf. This research aims to replace chemical surfactants in adjuvant by biosurfactants for reducing a negative impact on antagonistic microorganisms and crops. Biosurfactant was produced from Brevibacterium casei NK8 and used as a cell-free broth solution containing a biosurfactant concentration of 3.7 g/L. The studies of microemulsion formation and phase behavior were applied to obtain the suitable composition of biosurfactant-based adjuvant, consisting of cell-free broth (70-80%), coconut oil-based fatty alcohol C12-14 (3) ethoxylate (1-7%), and sodium chloride (8-30%). The suitable formula, achieving Winsor Type III microemulsion (bicontinuous), was 80% of cell-free broth, 7% of fatty alcohol C12-14 (3) ethoxylate, and 8% sodium chloride. This formula reduced the contact angle of water on parafilm from 70 to 31 degrees. The non-phytotoxicity against plant seed of Oryza sativa and Brassica rapa subsp. pekinensis were obtained from biosurfactant-based adjuvant (germination index equal and above 80%), while sodium dodecyl sulfate and tween80 showed phytotoxic effects to these plant seeds. The survival of Bacillus subtilis in biosurfactant-based adjuvant was higher than sodium dodecyl sulfate and tween80. The mixing of biosurfactant and plant-based surfactant could be considered as a viable, safer, and acceptable alternative to chemical adjuvant for sustainable organic farming.

Keywords: biosurfactant, microemulsion, bio-adjuvant, antagonistic microorganisms

Procedia PDF Downloads 134
914 Advantages of Fuzzy Control Application in Fast and Sensitive Technological Processes

Authors: Radim Farana, Bogdan Walek, Michal Janosek, Jaroslav Zacek

Abstract:

This paper presents the advantages of fuzzy control use in technological processes control. The paper presents a real application of the Linguistic Fuzzy-Logic Control, developed at the University of Ostrava for the control of physical models in the Intelligent Systems Laboratory. The paper presents an example of a sensitive non-linear model, such as a magnetic levitation model and obtained results which show how modern information technologies can help to solve actual technical problems. A special method based on the LFLC controller with partial components is presented in this paper followed by the method of automatic context change, which is very helpful to achieve more accurate control results. The main advantage of the used system is its robustness in changing conditions demonstrated by comparing with conventional PID controller. This technology and real models are also used as a background for problem-oriented teaching, realized at the department for master students and their collaborative as well as individual final projects.

Keywords: control, fuzzy logic, sensitive system, technological proves

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913 Manufacturing Process of Rubber Cement Composite Paver Block

Authors: Ratnadip Natwarbhai Bhoi

Abstract:

The objective of this research paper is to study waste tire crumb rubber granules as a partial concrete replacement by the different percentages of facing layer thickness and without facing layer in the production of rubber cement composite paver block. The physical properties of RCCRP compressive strength, flexural strength, abrasion strength density, and water absorption testing by the IS 15658:2006 method. All these physical properties depend upon the ratio of crumb rubber uses. The result showed that the with facing layer at 15 mm, 25 mm, totally rubberized and without facing layer had little effect on compressive strength, flexural strength and abrasion resistance properties. Water absorption is also important for the service life of the product. The crumb rubber paver block also performed quite well in both compressive strength and abrasion resistance. The rubber cement composite rubber paver block is suitable for nonstructural purposes, such as being lightweight and easy installation for the walkway, sidewalks, and playing area applications.

Keywords: rubber cement, crumb rubber, composite, layer

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912 Damage Localization of Deterministic-Stochastic Systems

Authors: Yen-Po Wang, Ming-Chih Huang, Ming-Lian Chang

Abstract:

A scheme integrated with deterministic–stochastic subspace system identification and the method of damage localization vector is proposed in this study for damage detection of structures based on seismic response data. A series of shaking table tests using a five-storey steel frame has been conducted in National Center for Research on Earthquake Engineering (NCREE), Taiwan. Damage condition is simulated by reducing the cross-sectional area of some of the columns at the bottom. Both single and combinations of multiple damage conditions at various locations have been considered. In the system identification analysis, either full or partial observation conditions have been taken into account. It has been shown that the damaged stories can be identified from global responses of the structure to earthquakes if sufficiently observed. In addition to detecting damage(s) with respect to the intact structure, identification of new or extended damages of the as-damaged (ill-conditioned) counterpart has also been studied. The proposed scheme proves to be effective.

Keywords: damage locating vectors, deterministic-stochastic subspace system, shaking table tests, system identification

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911 Analytics Capabilities and Employee Role Stressors: Implications for Organizational Performance

Authors: Divine Agozie, Muesser Nat, Eric Afful-Dadzie

Abstract:

This examination attempts an analysis of the effect of business intelligence and analytics (BI&A) capabilities on organizational role stressors and the implications of such an effect on performance. Two hundred twenty-eight responses gathered from seventy-six firms across Ghana were analyzed using the Partial Least Squares Structural Equation Modelling (PLS-SEM) approach to validate the hypothesized relationships identified in the research model. Findings suggest both endogenous and exogenous dependencies of the sensing capability on the multiple role requirements of personnel. Further, transforming capability increases role conflict, whereas driving capability of BI&A systems impacts role conflict and role ambiguity. This study poses many practical insights to firms seeking to acquire analytics capabilities to drive performance and data-driven decision-making. It is important for firms to consider balancing role changes and task requirements before implementing and post-implementation stages of BI&A innovations.

Keywords: business intelligence and analytics, dynamic capabilities view, organizational stressors, structural equation modelling

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910 Diagnostic of Breakdown in High Voltage Bushing Power Transformer 500 kV Cirata Substation

Authors: Andika Bagaskara, Andhika Rizki Pratama, Lalu Arya Repatmaja, Septhian Ditaputra Raharja

Abstract:

The power transformer is one of the critical things in system transmission. Regular testing of the power transformer is very important to maintain the reliability of the power. One of the causes of the failure of the transformer is the breakdown of insulation caused by the presence of voids in the equipment that is electrified. As a result of the voids that occur in this power transformer equipment, it can cause partial discharge. Several methods were used to determine the occurrence of damage to the power transformer equipment, such as Sweep Frequency Response Analysis (SFRA) and Tan Delta. In Inter Bus Transformer (IBT) 500/150 kV Cirata Extra High Voltage (EHV) Substation, a breakdown occurred in the T-phase tertiary bushing. From the lessons learned in this case, a complete electrical test was carried out. From the results of the complete electrical test, there was a suspicion of deterioration in the post-breakdown SFRA results. After overhaul and inspection, traces of voids were found on the tertiary bushing, which indicated a breakdown in the tertiary bushing of the IBT 500/150kV Cirata Substation transformer.

Keywords: void, bushing, SFRA, Tan Delta

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909 Optimal Bayesian Chart for Controlling Expected Number of Defects in Production Processes

Authors: V. Makis, L. Jafari

Abstract:

In this paper, we develop an optimal Bayesian chart to control the expected number of defects per inspection unit in production processes with long production runs. We formulate this control problem in the optimal stopping framework. The objective is to determine the optimal stopping rule minimizing the long-run expected average cost per unit time considering partial information obtained from the process sampling at regular epochs. We prove the optimality of the control limit policy, i.e., the process is stopped and the search for assignable causes is initiated when the posterior probability that the process is out of control exceeds a control limit. An algorithm in the semi-Markov decision process framework is developed to calculate the optimal control limit and the corresponding average cost. Numerical examples are presented to illustrate the developed optimal control chart and to compare it with the traditional u-chart.

Keywords: Bayesian u-chart, economic design, optimal stopping, semi-Markov decision process, statistical process control

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908 Collaborative Technology Implementation Success and Knowledge Capacity: Case of Tunisian Banks with Mixed Capital

Authors: Amira Khelil, Habib Affes

Abstract:

Organization resource planning implementation success is important. Today`s competitors in business, in enterprise resource planning and in managing are becoming one of the main tools of achieving competitiveness in business. Resource technologies are considered as an infrastructure to create and maintain business to improve front and back-office efficiency and effectiveness. This study is significant to bring new ideas in determining the key antecedents which are technological resource planning implementation based on knowledge capacity perspectives and help to understand the key success factor in the Tunisian banks. Based on a survey of 150 front office Tunisian agents working in Tunisian banks with mixed capital, using Groupware system, only 51 respondents had given feedback to this survey. By using Warp PLS 3.0, through several tests the relationship between knowledge capability and Groupware implementation success having beta coefficient 0.37 and P-Value <0.01. This result highlights that knowledge capability of bank agent can influence the success of the Groupware implementation.

Keywords: groupware implementation, knowledge capacity, partial least squares method, Tunisian banks

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907 Cancer Stem Cell-Associated Serum Proteins Obtained by Maldi TOF/TOF Mass Spectrometry in Women with Triple-Negative Breast Cancer

Authors: Javier Enciso-Benavides, Fredy Fabian, Carlos Castaneda, Luis Alfaro, Alex Choque, Aparicio Aguilar, Javier Enciso

Abstract:

Background: The use of biomarkers in breast cancer diagnosis, therapy, and prognosis has gained increasing interest. Cancer stem cells (CSCs) are a subpopulation of tumor cells that can drive tumor initiation and may cause relapse. Therefore, due to the importance of diagnosis, therapy, and prognosis, several biomarkers that characterize CSCs have been identified; however, in treatment-naïve triple-negative breast tumors, there is an urgent need to identify new biomarkers and therapeutic targets. According to this, the aim of this study was to identify serum proteins associated with cancer stem cells and pluripotency in women with triple-negative breast tumors in order to subsequently identify a biomarker for this type of breast tumor. Material and Methods: Whole blood samples from 12 women with histopathologically diagnosed triple-negative breast tumors were used after obtaining informed consent from the patient. Blood serum was obtained by conventional procedure and frozen at -80ºC. Identification of cancer stem cell-associated proteins was performed by matrix-assisted laser desorption/ionisation-assisted laser desorption/ionisation mass spectrometry (MALDI-TOF MS), protein analysis was obtained using the AB Sciex TOF/TOF™ 5800 system (AB Sciex, USA). Sequences not aligned by ProteinPilot™ software were analyzed by Protein BLAST. Results: The following proteins related to pluripotency and cancer stem cells were identified by MALDI TOF/TOF mass spectrometry: A-chain, Serpin A12 [Homo sapiens], AIEBP [Homo sapiens], Alpha-one antitrypsin, AT {internal fragment} [human, partial peptide, 20 aa] [Homo sapiens], collagen alpha 1 chain precursor variant [Homo sapiens], retinoblastoma-associated protein variant [Homo sapiens], insulin receptor, CRA_c isoform [Homo sapiens], Hydroxyisourate hydrolase [Streptomyces scopuliridis], MUCIN-6 [Macaca mulatta], Alpha-actinin-3 [Chrysochloris asiatica], Polyprotein M, CRA_d isoform, partial [Homo sapiens], Transcription factor SOX-12 [Homo sapiens]. Recommendations: The serum proteins identified in this study should be investigated in the exosome of triple-negative breast cancer stem cells and in the blood serum of women without breast cancer. Subsequently, proteins found only in the blood serum of women with triple-negative breast cancer should be identified in situ in triple-negative breast cancer tissue in order to identify a biomarker to study the evolution of this type of cancer, or that could be a therapeutic target. Conclusions: Eleven cancer stem cell-related serum proteins were identified in 12 women with triple-negative breast cancer, of which MUCIN-6, retinoblastoma-associated protein variant, transcription factor SOX-12, and collagen alpha 1 chain are the most representative and have not been studied so far in this type of breast tumor. Acknowledgement: This work was supported by Proyecto CONCYTEC–Banco Mundial “Mejoramiento y Ampliacion de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovacion Tecnologica” 8682-PE (104-2018-FONDECYT-BM-IADT-AV).

Keywords: triple-negative breast cancer, MALDI TOF/TOF MS, serum proteins, cancer stem cells

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906 Value-Added Tax Exemptions and Farm-Level Productivity: The Case of Rice, Millet, and Maize in Senegal

Authors: Awa Diouf

Abstract:

Since 2004, inputs specific to the agricultural sector have been exempt from VAT in Senegal. This paper measures, using the Naatal Mbay survey, the impact of this reform on agricultural productivity. The survey covers a sample of 3,122 rice, millet and maize farms for the 2016 crop year. The regressions show that tax incentives are ineffective in improving partial productivity of the land factor: the higher the share of the value of exemptions in the higher the production costs, the less productive the operation. The negative effect of the exemptions on productivity is accentuated for the most intensive agricultural area: the Senegal River Delta, and the most intensive crop: irrigated rice. This relationship could stem from a decrease in allocative efficiency: farmers have overinvested in the most accessible inputs. The loose budget constraint syndrome, therefore, explains this result: farmers who benefit more from exemptions reduce their managerial effort. The results suggest a removal of the VAT exemptions applied to finished products and agricultural inputs for a better efficiency of this tax, which typically taxes final consumption and should be neutral for the producer.

Keywords: agricultural productivity, agricultural taxation, Senegal, tax incentives

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905 Modified Step Size Patch Array Antenna for UWB Wireless Applications

Authors: Hamid Aslani, Ahmed Radwan

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In this paper, a single element microstrip antenna is presented for UWB applications by using techniques as partial ground plane and modified the shape of the patch. The antenna is properly designed to have a compact size and constant gain against frequency. The simulated results have done using two EM software and show good agreement with the measured results for the fabricated antenna. Then a designing of two elements patch antenna array for UWB in the frequency band of 3.1-10 GHz is presented in this paper. The array is constructed by means of feeding two omni-directional modified circular patch elements with a modified power divider. Experimental results show that the array has a stable radiation pattern and low return loss over a broad bandwidth of 64% (3.1–10 GHz). Due to its planar profile, physically compact size, wide impedance bandwidth, directive performance over a wide bandwidth proposed antenna is a good candidate for portable UWB applications and other UWB integrated circuits.

Keywords: ultra wide band, radiation performance, microstrip antenna, size miniaturized antenna

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904 Development of a Laboratory Laser-Produced Plasma “Water Window” X-Ray Source for Radiobiology Experiments

Authors: Daniel Adjei, Mesfin Getachew Ayele, Przemyslaw Wachulak, Andrzej Bartnik, Luděk Vyšín, Henryk Fiedorowicz, Inam Ul Ahad, Lukasz Wegrzynski, Anna Wiechecka, Janusz Lekki, Wojciech M. Kwiatek

Abstract:

Laser produced plasma light sources, emitting high intensity pulses of X-rays, delivering high doses are useful to understand the mechanisms of high dose effects on biological samples. In this study, a desk-top laser plasma soft X-ray source, developed for radio biology research, is presented. The source is based on a double-stream gas puff target, irradiated with a commercial Nd:YAG laser (EKSPLA), which generates laser pulses of 4 ns time duration and energy up to 800 mJ at 10 Hz repetition rate. The source has been optimized for maximum emission in the “water window” wavelength range from 2.3 nm to 4.4 nm by using pure gas (argon, nitrogen and krypton) and spectral filtering. Results of the source characterization measurements and dosimetry of the produced soft X-ray radiation are shown and discussed. The high brightness of the laser produced plasma soft X-ray source and the low penetration depth of the produced X-ray radiation in biological specimen allows a high dose rate to be delivered to the specimen of over 28 Gy/shot; and 280 Gy/s at the maximum repetition rate of the laser system. The source has a unique capability for irradiation of cells with high pulse dose both in vacuum and He-environment. Demonstration of the source to induce DNA double- and single strand breaks will be discussed.

Keywords: laser produced plasma, soft X-rays, radio biology experiments, dosimetry

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903 A Study of the Formation, Existence and Stability of Localised Pulses in PDE

Authors: Ayaz Ahmad

Abstract:

TOPIC: A study of the formation ,existness and stability of localised pulses in pde Ayaz Ahmad ,NITP, Abstract:In this paper we try to govern the evolution deterministic variable over space and time .We analysis the behaviour of the model which allows us to predict and understand the possible behaviour of the physical system .Bifurcation theory provides a basis to systematically investigate the models for invariant sets .Exploring the behaviour of PDE using bifurcation theory which provides many challenges both numerically and analytically. We use the derivation of a non linear partial differential equation which may be written in this form ∂u/∂t+c ∂u/∂x+∈(∂^3 u)/(∂x^3 )+¥u ∂u/∂x=0 We show that the temperature increased convection cells forms. Through our work we look for localised solution which are characterised by sudden burst of aeroidic spatio-temporal evolution. Key word: Gaussian pulses, Aeriodic ,spatio-temporal evolution ,convection cells, nonlinearoptics, Dr Ayaz ahmad Assistant Professor Department of Mathematics National institute of technology Patna ,Bihar,,India 800005 [email protected] +91994907553

Keywords: Gaussian pulses, aeriodic, spatio-temporal evolution, convection cells, nonlinear optics

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902 Dynamics of a Reaction-Diffusion Problems Modeling Two Predators Competing for a Prey

Authors: Owolabi Kolade Matthew

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In this work, we investigate both the analytical and numerical studies of the dynamical model comprising of three species system. We analyze the linear stability of stationary solutions in the one-dimensional multi-system modeling the interactions of two predators and one prey species. The stability analysis has a lot of implications for understanding the various spatiotemporal and chaotic behaviors of the species in the spatial domain. The analysis results presented have established the possibility of the three interacting species to coexist harmoniously, this feat is achieved by combining the local and global analyzes to determine the global dynamics of the system. In the presence of diffusion, a viable exponential time differencing method is applied to multi-species nonlinear time-dependent partial differential equation to address the points and queries that may naturally arise. The scheme is described in detail, and justified by a number of computational experiments.

Keywords: asymptotically stable, coexistence, exponential time differencing method, global and local stability, predator-prey model, nonlinear, reaction-diffusion system

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901 The Study of Sensory Breadth Experiences in an Online Try-On Environment

Authors: Tseng-Lung Huang

Abstract:

Sensory breadth experiences, such as visualization, a sense of self-location, and haptic experiences, are critical in an online try-on environment. This research adopts an emotional appeal perspective, including concrete and abstract effects, to clarify the relationship between sensory experience and consumer's behavior intention in an online try-on context. This study employed an augmented reality interactive technology (ARIT) in an online clothes-fitting context and applied snowball sampling using e-mail to invite online consumers, first to use ARIT for trying on online apparel and then to complete a questionnaire. One hundred sixty-eight valid questionnaires were collected, and partial least squares (PLS) path modeling was used to test our hypotheses. The results showed that sensory breadth, by arousing concrete effect, induces impulse buying intention and willingness to pay a price premium of online shopping. Parasocial presence, as an abstract effect, diminishes the effect of concrete effects on willingness to pay a price premium.

Keywords: sensory breadth, impulsive behavior, price premium, emotional appeal, online try-on context

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900 Principles of Municipal Sewage Sludge Bioconversion into Biomineral Fertilizer

Authors: K. V. Kalinichenko, G. N. Nikovskaya

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The efficiency of heavy metals removal from sewage sludge in bioleaching with heterotrophic, chemoautotrophic (sulphur-oxidizing) sludge cenoses and chemical leaching (in distilled water, weakly acidic or alkaline medium) was compared. The efficacy of heavy metals removal from sewage sludge varied from 83 % (Zn) up to 14 % (Cr) and followed the order: Zn > Mn > Cu > Ni > Co > Pb > Cr. The advantages of metals bioleaching process at heterotrophic metabolism was shown. A new process for bioconversation of sewage sludge into fertilizer at middle temperature after partial heavy metals removal was developed. This process is based on enhancing vital ability of heterotrophic microorganisms by adding easily metabolized nutrients and synthesis of metabolites by growing sludge cenoses. These metabolites possess the properties of heavy metals extractants and flocculants which provide sludge flocks sedimentation and concentration. The process results in biomineral fertilizer with immobilized sludge bioelements with prolonged action. The fertilizer obtained satisfied the EU limits for the sewage sludge of agricultural utilization. High efficiency of the biomineral fertilizers obtained has been demonstrated in vegetation experiments.

Keywords: fertilizer, heavy metals, leaching, sewage sludge

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899 Production of Metal Matrix Composites with Diamond for Abrasive Cutting Resistance by Gas Infiltration Casting

Authors: Haydar S. Al Shabbani, M. Marshall, R. Goodall

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Metal matrix composites (MMCs) have been explored for many applications for many decades. Recently, this includes investigations for thermal applications associated with electronics, such as in heat sinks. Here, to promote thermal conductivity, composites of a metal matrix with diamond particles are used. However, this class of composites has not yet been extensively examined for mechanical and tribological behavior, especially for applications that require extreme mechanical and tribological strength, such as the resistance to abrasive cutting. Therefore, this research seeks to develop a composite material with metal matrix and diamond particles which resist abrasive and cutting forces. The development progresses through a series of steps, exploring methods to process the material, understanding the mechanics of abrasive behavior and optimizing the composite structure to resist abrasive cutting. In processing, infiltration casting under gas pressure has been applied to molten aluminum to obtain a significant penetration of the metal into a preform of diamond particles. Different diamond particle sizes were used with different surface modifications (coated/uncoated), and to compare resulting composites with the same particle sizes. Al-1 wt.% Mg as a matrix alloy was utilised to investigate the possible effect of Mg on bonding phases during the infiltration process. The mechanical behavior and microstructure of the materials produced have been characterised. These tests showed that the surface modification of the diamond particles with a reactive material (Ti-coating) has an important role for enhancing the bonding between the aluminium matrix and diamond reinforcement as apparent under SEM observation. The effect of this improved bond is seen in the cutting resistance of the material.

Keywords: aluminium, composites, diamond, Ti-coated, tribology

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898 First Principle Calculations of the Structural and Optoelectronic Properties of Cubic Perovskite CsSrF3

Authors: Meriem Harmel, Houari Khachai

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We have investigated the structural, electronic and optical properties of a compound perovskite CsSrF3 using the full-potential linearized augmented plane wave (FP-LAPW) method within density functional theory (DFT). In this approach, both the local density approximation (LDA) and the generalized gradient approximation (GGA) were used for exchange-correlation potential calculation. The ground state properties such as lattice parameter, bulk modulus and its pressure derivative were calculated and the results are compared whit experimental and theoretical data. Electronic and bonding properties are discussed from the calculations of band structure, density of states and electron charge density, where the fundamental energy gap is direct under ambient conditions. The contribution of the different bands was analyzed from the total and partial density of states curves. The optical properties (namely: the real and the imaginary parts of the dielectric function ε(ω), the refractive index n(ω) and the extinction coefficient k(ω)) were calculated for radiation up to 35.0 eV. This is the first quantitative theoretical prediction of the optical properties for the investigated compound and still awaits experimental confirmations.

Keywords: DFT, fluoroperovskite, electronic structure, optical properties

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897 Upconversion Nanomaterials for Applications in Life Sciences and Medicine

Authors: Yong Zhang

Abstract:

Light has proven to be useful in a wide range of biomedical applications such as fluorescence imaging, photoacoustic imaging, optogenetics, photodynamic therapy, photothermal therapy, and light controlled drug/gene delivery. Taking photodynamic therapy (PDT) as an example, PDT has been proven clinically effective in early lung cancer, bladder cancer, head, and neck cancer and is the primary treatment for skin cancer as well. However, clinical use of PDT is severely constrained by the low penetration depth of visible light through thick tissue, limiting its use to target regions only a few millimeters deep. One way to enhance the range is to use invisible near-infrared (NIR) light within the optical window (700–1100nm) for biological tissues, extending the depth up to 1cm with no observable damage to the intervening tissue. We have demonstrated use of NIR-to-visible upconversion fluorescent nanoparticles (UCNPs), emitting visible fluorescence when excited by a NIR light at 980nm, as a nanotransducer for PDT to convert deep tissue-penetrating NIR light to visible light suitable for activating photosensitizers. The unique optical properties of UCNPs enable the upconversion wavelength to be tuned and matched to the activation absorption wavelength of the photosensitizer. At depths beyond 1cm, however, tissue remains inaccessible to light even within the NIR window, and this critical depth limitation renders existing phototherapy ineffective against most deep-seated cancers. We have demonstrated some new treatment modalities for deep-seated cancers based on UCNP hydrogel implants and miniaturized, wirelessly powered optoelectronic devices for light delivery to deep tissues.

Keywords: upconversion, fluorescent, nanoparticle, bioimaging, photodynamic therapy

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896 Photophysics and Rotational Relaxation Dynamics of 6-Methoxyquinoline Fluorophore in Cationic Alkyltrimethylammonium Bromide Micelles

Authors: Tej Varma Y, Debi D. Pant

Abstract:

Photophysics and rotational dynamics of the fluorescent probe, 6-methoxyquinoline (6MQ) with cationic surfactant, alkyltrimethylammonium bromide (nTAB) micelle solutions have been investigated (n = 12, 14 and 16). Absorption and emission peaks of the dye have been observed to shift at concentrations around critical micellar concentration (cmc) of nTAB compared to that of bulk solutions suggesting probe is in a lower polar environment. The probe senses changes in polarity (ET (30)) brought about by variation of surfactant chain length concentration and is invariably solubilized in the aqueous interface or palisade layer. The order of change in polarity observed was DTAB > CTAB > TTAB. The binding constant study shows that the probe binds strongest with TTAB (is of the order TTAB > CTAB > DTAB) due to deeper penetration into the micelle. The anisotropy decay for the probe in all the nTAB micelles studied have been rationalized based on a two-step model consisting of fast-restricted rotation of the probe and slow lateral diffusion of the probe in the micelle that is coupled to the overall rotation of the micelle. Fluorescence lifetime measurements of probe in the cationic micelles demonstrate the close proximity of the 6MQ to the Br - counterions. The fluorescence lifetimes of TTAB and DTAB are much shorter than in CTAB. These results indicate that 6MQ resides to a substantial degree in the head group region of the micelles. All the changes observed in the steady state fluorescence, microenvironment, fluorescence lifetimes, fluorescence anisotropy, and other calculations are in agreement with each other suggesting binding of the cationic surfactant with the neutral dye molecule.

Keywords: photophysics, chain length, ntaB, micelles

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895 Prediction of Damage to Cutting Tools in an Earth Pressure Balance Tunnel Boring Machine EPB TBM: A Case Study L3 Guadalajara Metro Line (Mexico)

Authors: Silvia Arrate, Waldo Salud, Eloy París

Abstract:

The wear of cutting tools is one of the most decisive elements when planning tunneling works, programming the maintenance stops and saving the optimum stock of spare parts during the evolution of the excavation. Being able to predict the behavior of cutting tools can give a very competitive advantage in terms of costs and excavation performance, optimized to the needs of the TBM itself. The incredible evolution of data science in recent years gives the option to implement it at the time of analyzing the key and most critical parameters related to machinery with the purpose of knowing how the cutting head is performing in front of the excavated ground. Taking this as a case study, Metro Line 3 of Guadalajara in Mexico will develop the feasibility of using Specific Energy versus data science applied over parameters of Torque, Penetration, and Contact Force, among others, to predict the behavior and status of cutting tools. The results obtained through both techniques are analyzed and verified in the function of the wear and the field situations observed in the excavation in order to determine its effectiveness regarding its predictive capacity. In conclusion, the possibilities and improvements offered by the application of digital tools and the programming of calculation algorithms for the analysis of wear of cutting head elements compared to purely empirical methods allow early detection of possible damage to cutting tools, which is reflected in optimization of excavation performance and a significant improvement in costs and deadlines.

Keywords: cutting tools, data science, prediction, TBM, wear

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894 Bankruptcy Prediction Analysis on Mining Sector Companies in Indonesia

Authors: Devina Aprilia Gunawan, Tasya Aspiranti, Inugrah Ratia Pratiwi

Abstract:

This research aims to classify the mining sector companies based on Altman’s Z-score model, and providing an analysis based on the Altman’s Z-score model’s financial ratios to provide a picture about the financial condition in mining sector companies in Indonesia and their viability in the future, and to find out the partial and simultaneous impact of each of the financial ratio variables in the Altman’s Z-score model, namely (WC/TA), (RE/TA), (EBIT/TA), (MVE/TL), and (S/TA), toward the financial condition represented by the Z-score itself. Among 38 mining sector companies listed in Indonesia Stock Exchange (IDX), 28 companies are selected as research sample according to the purposive sampling criteria.The results of this research showed that during 3 years research period at 2010-2012, the amount of the companies that was predicted to be healthy in each year was less than half of the total sample companies and not even reach up to 50%. The multiple regression analysis result showed that all of the research hypotheses are accepted, which means that (WC/TA), (RE/TA), (EBIT/TA), (MVE/TL), and (S/TA), both partially and simultaneously had an impact towards company’s financial condition.

Keywords: Altman’s Z-score model, financial condition, mining companies, Indonesia

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893 Simulation of 1D Dielectric Barrier Discharge in Argon Mixtures

Authors: Lucas Wilman Crispim, Patrícia Hallack, Maikel Ballester

Abstract:

This work aims at modeling electric discharges in gas mixtures. The mathematical model mimics the ignition process in a commercial spark-plug when a high voltage is applied to the plug terminals. A longitudinal unidimensional Cartesian domain is chosen for the simulation region. Energy and mass transfer are considered for a macroscopic fluid representation, while energy transfer in molecular collisions and chemical reactions are contemplated at microscopic level. The macroscopic model is represented by a set of uncoupled partial differential equations. Microscopic effects are studied within a discrete model for electronic and molecular collisions in the frame of ZDPlasKin, a plasma modeling numerical tool. The BOLSIG+ solver is employed in solving the electronic Boltzmann equation. An operator splitting technique is used to separate microscopic and macroscopic models. The simulation gas is a mixture of atomic Argon neutral, excited and ionized. Spatial and temporal evolution of such species and temperature are presented and discussed.

Keywords: CFD, electronic discharge, ignition, spark plug

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892 Formulation and in vitro Evaluation of Transdermal Delivery of Articaine

Authors: Dinakaran Venkatachalam, Paul Chambers, Kavitha Kongara, Preet Singh

Abstract:

The objective of this study is to formulate different topical preparations containing articaine and to investigate their permeation through goat skin. Initially, articaine and its hydrochloride salt were compared for in vitro permeation using Franz cell model. Goat skin samples were collected after euthanizing male goat kids purchased from the dairy goat farmers. Subcutaneous fat was removed and the skin was mounted on the donor chamber (orifice area 1.00 cm²) and drugs were applied onto the epidermis. Phosphate buffer saline (pH 7.4) was used to maintain sink condition in the receptor chamber (8 ml) of the Franz cell. Samples (0.4 ml) were collected at various intervals over 24 hours after each sampling equal volume of PBS was replaced in the receptor chamber. Articaine in the collected samples were quantified using LC/MS. The results suggested that articaine free base permeates better than its hydrochloride salt through goat skin. This study results support the fact that local anesthetics in its base form are lipophilic and thus penetrates faster through cell membranes than their salts. Later, articaine free base was formulated either using ethanol and octyl salicylate or dimethyl sulfoxide (DMSO) as penetration enhancers and was compared for in vitro permeation. The transdermal flux of articaine in the formulation containing DMSO was approximately 3.8 times higher than that of the formulation containing ethanol and octyl salicylate. Further studies to evaluate the local anesthetic efficacy of the topical formulation containing articaine for dermal anesthesia in animals have been planned.

Keywords: articaine, dermal anesthesia, local anesthetic, transdermal

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