bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Aging Time on the Structural Changes of Cassava Thermoplastic Starch
Authors: Mina José H. , Valadez Alex , Herrera-Franco Pedro J. , Toledano Tanit 
Published: January 2012

ABSTRACTIn this work the change in the structural properties of cassava (manihot sculenta Crantz) thermoplastic starch (TPS) under controlled environment (humidity and temperature) was studied. Fourier Transform Infrared spectroscopy (FTIR) and X-ray diffraction (XRD) results showed an evident increasing in the amorphous phase of the TPS regarding the native starch. There was a relative decrease of the band at 1047 cm-1 associated to crystalline structure of starch compared to the amorphous peak at 1022 cm-1. The X-ray diffraction patterns confirmed the increment of the amorphous phase in the TPS samples. Likewise the X-ray diffraction patterns shows evidence of residual type C crystallinity and the formation of a new crystalline phase type VH due to the orientation induced in plasticization process. In first stage of conditioning the tensile yield stress drops from 7.5 drops to 0.5 MPa and the break strain increases 1000%. At the same time it seems that the crystallinity of the samples increases as was evidenced by the gradually increasing of the FTIR band at 1047 cm-1. In a second stage, the yield stress increases, the break strain drops and the crystallinity continue growing steadily. These findings suggest that coexist two phenomena simultaneously in the samples. A phenomenon of re-crystallization (retrogradation) that tends to make the material more stiff and a process of plasticization that tends to softening it. It seems that the latter mechanism predominates in the first stage, at short times, and the former in the second stage, at older times.
Microstructural and Mechanical Properties Enhancement in Ultrafine Grained Ni-Cr Alloy
Authors: Song Kuk Hyun , Lee Hye Jin , Kim Han Sol , Kim Won Yong 
Published: January 2012

ABSTRACTThe present study was carried out to evaluate the microstructures and mechanical properties of severely deformed Ni-30Cr alloy. Cross-roll rolling (CRR) as severe plastic deformation (SPD) process was introduced and Ni-30Cr alloy sheets were cold rolled to a 90% thickness reduction and subsequently annealed at 700 °C for 30 min so as to obtain the recrystallized microstructure. For the analysis of grain boundary character distributions (GBCDs), electron back-scattered diffraction (EBSD) technique was introduced. CRR on Ni-30Cr alloy was effective to enhance the grain refinement through heat treatment; consequently, average grain size was significantly reduced from 33 μm in initial material to 0.6 μm in CRR processed material. This grain refinement directly affected the mechanical properties improvement, in which yield and tensile strengths were significantly increased than those of initial material. In this study, we systematically discussed the grain refinement, accompanying with increase in mechanical properties, in terms of the effective strain imposed by CRR, comparing with conventional rolling (CR).
VLS Synthesis and Characterization of SnO2 Nanowires
Authors: Castillo Dulce N. , Becerril Tomás D. , Andrés Enrique R. , Santiesteban Héctor J. , Salgado Godofredo G. 
Published: January 2012

ABSTRACTWe have synthesized core-shell 1D nanostructures by the Vapor-Liquid-Solid (VLS) mechanism. Gold (Au) was used as a catalyst and tin oxide (SnO) powder as a precursor; the growth temperature was of 600 °C. These structures were characterized by XRD, SEM, TEM, EDS, and PL. The nanowires have an average diameter of 20 nm and their lengths are of tens of micrometers; the core is tin dioxide (SnO2) with the tetragonal rutile structure and it has an average diameter of 12 nm; the shell is amorphous Sn of 8 nm average thickness. Photoluminescence measurements show a broad band in the 400-800 nm range. On the same growth process, SnO2 nanoparticles and a mixture of SnO2 rods and wires were also obtained, at 400 °C and 800 °C, respectively.
Transmission properties of multilayered Period Doubling and Silver-Mean graphene structures
Authors: Rodríguez-Arellano G. , Juárez-López D. P. , Madrigal-Melchor J. , Pérez-Álvarez R. , Martínez-Orozco J. C. , Rodríguez-Vargas I. 
Published: January 2012

ABSTRACTWe present the propagation properties of Dirac-electrons in multilayered Period-Doubling (MPDGS) and Silver-Mean (MSMGS) graphene structures. The multilayered graphene structures are built arranging breaking and non-breaking symmetry substrates such as SiC and SiO2 following a given quasirregular substitution rule locating on them a graphene sheet. We have implemented the Transfer Matrix technique to calculate the transmittance of these multilayered graphene structures. This technique allows us to analyze readily the main differences of the transmission properties between MPDGS and MSMGS.
Response of herbaceous vegetation functional diversity to land use change across five sites in Europe and Israel
Authors: Lavorel Sandra , de Bello Francesco , Grigulis Karl , Lepš Jan , Garnier Eric , Castro Helena , Dolezal Jiri , Godolet Carly , Quétier Fabien , Thébault Aurélie 
Published: January 2012

Only a few studies have examined responses of grassland functional diversity to management and major environmental gradients, in order to address the question of whether grassland use can promote functional divergence. For five grassland sites in Israel, Portugal, the Czech Republic, Mediterranean France, and the French Alps, where traditional grassland management is being abandoned, we quantified community-weighted means (CWM) and functional divergence (FDvg) for the three Leaf-Height-Seed (LHS) traits, individually and in combination. Responses of CWM and FDvg to land use were analyzed by mixed linear models with aridity, phosphorus, fertility, and the fractions of grasses and annuals as covariates.Responses of community-weighted traits to land use were consistent with current knowledge. More intense management favored plants with more rapid resource acquisition (high Specific Leaf Area, or SLA), whereas abandonment or less intense grassland management increased the dominance by tall plants with more conservative strategies (low SLA). Seed weight did not respond to land use. For the three traits and their combination, functional divergence decreased in response to land use change overall. Detailed responses, however, varied depending on sites and especially their climate. At the two French sites, traditional site management promoted functional divergence within communities by suppressing dominance by large perennial tussocks, whereas at the two Mediterranean sites it is likely that the drier climate promoted a functionally diverse pool of species tolerant to grazing.This study demonstrates how simultaneous analyses of variations in community-mean traits and functional divergence for a focused set of traits offer promising avenues to understand mechanisms of community response to environmental change.
Prevalence of Enamel Defects in Permanent Teeth of Patients with Complete Cleft Lip and Palate
Authors: Ruiz Luciana Angélica , Maya Rafael Ribeiro , D'alpino Paulo Henrique Perlatt , Atta Maria Teresa , Da Rocha Svizero Nádia 
Published: January 2012

Objective To evaluate the prevalence, types, location, and characteristics of enamel defects in anterior permanent teeth of patients with complete unilateral and bilateral cleft lip and palate, as well as the relation with the cleft. Setting Hospital for Rehabilitation of Craniofacial Anomalies, Bauru, São Paulo, Brazil. Participants Eighty patients of both genders, 12 years and older, with unilateral or bilateral cleft lip and palate. Methods A single examiner carried out clinical examination under artificial light with a dental probe and mirror after drying teeth according to the modified DDE index. Results Seventy-four of 80 patients presented with at least one tooth affected by enamel defects: 165 of 325 evaluated teeth (50.8%) presented enamel defects, with hypoplasia being the most prevalent (50.7%), followed by diffuse opacity (23.1%) and demarcated opacity (18.4%). The most affected tooth was 21 (36.5%), followed by 11 (34%), located at the middle (40%) and incisal (33%) thirds. Most defects occur at the buccal surface (47.7%), followed by the distal (22.7%), the mesial (19%), and the palatal (10.6%) surfaces. A significant relationship was found between the cleft side and enamel defects. Conclusion Upper anterior teeth of patients with complete cleft lip and palate present a high prevalence of enamel defects; the highest percentage on the cleft side suggests that the cleft does influence the occurrence of enamel defects in permanent teeth.
Notch1-Mediated Tumor Suppression in Cervical Cancer with the Involvement of SST Signaling and Its Application in Enhanced SSTR-Targeted Therapeutics
Authors: Franko-Tobin Laura G. , Mackey L. Vienna , Huang Wei , Song Xiangwei , Jin Baofeng , Luo Jing , Morris Lynsie M. , Liu Minqiu , Fuselier Joseph A. , Coy David H. , Wu Lizi , Sun Lichun 
Published: January 2012

AbstractThe role of Notch signaling in cervical cancer is seemingly controversial. To confirm the function of Notch signaling in this type of cancer, we established a stable Notch1-activated cervical cancer HeLa cell line. We found that Notch1 activation resulted in apoptosis, cell cycle arrest, and tumor suppression. At the molecular level, we found that a variety of genes associated with cyclic AMP, G protein-coupled receptor, and cancer signaling pathways contributed to Notch1-mediated tumor suppression. We observed that the expression of somatostatin (SST) was dramatically induced by Notch1 signaling activation, which was accompanied by enhanced expression of the cognate SST receptor subtype 1 (SSTR1) and SSTR2. Certain genes, such as tumor protein 63 (TP63, p63), were upregulated, whereas others, such as B-cell lymphoma 2 (BCL-2), Myc, Akt, and STAT3, were downregulated. Subsequently, knockdown of Notch1-induced SST reversed Notch1-induced decrease of BCL-2 and increase of p63, indicating that Notch1-induced tumor suppression may be partly through upregulating SST signaling. Our findings support a possible crosstalk between Notch signaling and SST signaling. Moreover, Notch-induced SSTR activation could enhance SSTR-targeted cancer chemotherapy. Valproic acid (VPA), a histone deacetylase inhibitor, suppressed cell growth and upregulated the expression of Notch1 and SSTR2. A combination therapy with VPA and the SSTR2-targeting cytotoxic conjugate CPT-SST strongly led to greater suppression, as compared to each alone. Our findings thus provide us with a promising clinical opportunity for enhanced cancer therapy using combinations of Notch1-activating agents and SSTR2-targeting agents.
Potentials of Mouthwashes in Disinfecting Cariogenic Bacteria and Biofilms Leading to Inhibition of Caries
Authors: Oyanagi Takehiro , Tagami Junji , Matin Khairul 
Published: January 2012

Objectives:The aim of this study was to compare the effects of certain commercially available mouthwashes on cariogenic bacteria and biofilms, following the acquisition of inhibition potentials of caries.Materials and Methods:Mouthwashes containing I) chlorhexidine gluconate (CHG; 0.0005% w/v), II) benzethonium chloride (BTC; 0.01% w/v), III) an essential oil (Listerine), and IV) povidone-iodine (PVP-I; 0.035% w/v) were tested on planktonic cariogenic bacteria, biofilms, and an ex vivo caries model. Bacterial aliquots were inoculated with each solution separately and vortexed for 10 seconds at room temperature. Bacterial viability was subsequently investigated by fluorescence microscopy (FM) after staining with a BacLight viability kit and the number of colony-forming units (CFUs) was counted. Similarly, mouthwash solutions were applied to artificial cariogenic biofilms, and bacterial viability of the biofilms was investigated as stated above. Inhibition potentials of two selected mouthwashes of carious lesions were investigated using biofilm-induced caries and a secondary caries model. In all steps, a phosphate-buffered saline (PBS) solution was included as a control.Results:Planktonic cariogenic bacteria and bacteria embedded in biofilms were killed in remarkably large numbers with Listerine and PVP-I treatment compared to PBS and other gargles. CFU counts also showed significant reduction after treatment with Listerine and PVP-I compared to other solutions (P<0.05). Listerine also displayed significant (P<0.05) inhibition effects in preventing the progression of demineralization.Conclusion:Bactericidal potencies of the mouthwashes varied significantly, suggesting that mouthwashes like Listerine can be useful for the prevention of caries and secondary caries.
In-situ polymerized molecularly imprinted polymeric thin films used as sensing layers in surface plasmon resonance sensors: Mini-review focused on 2010–2011
Authors: Lépinay Sandrine , Kham Khémara , Millot Marie-Claude , Carbonnier Benjamin 
Published: January 2012

AbstractThis review provides a short overview of polymeric thin films incorporating molecular imprints within their 3D macromolecular structure as synthetic recognition elements and prepared by in situ polymerization for surface plasmon resonance application. This review starts with a brief reminder of the principle of surface plasmon resonance detection. The second section is focused on molecularly imprinted materials. Bulk and thin film polymer formats can be obtained by free radical polymerization, where the functional monomer interacts specifically with the template and the cross-linker controls the rigidity of the imprinted cavities. Grafting polymerization is presented as a method of choice for covalent attachment of ultra-thin molecularly imprinted films on a surface plasmon resonance metallic substrate. Examples of electropolymerized thin films are also provided. In the rest of this contribution, surface plasmon resonance applications of molecularly imprinted polymers reported mainly over the last two years are presented with respect to the preparation mode. Also, applications of gold nanoparticle/molecularly imprinted polymer composites for the design of surface plasmon resonance-based sensors with enhanced sensitivity due to the phenomenon of localized surface plasmon resonance induced by the presence of gold nanoparticles are summarized.
Extractive distillation modeling of the ternary system 2-methoxy-2-methylpropane-methanol-butan-1-ol
Authors: Labovská Zuzana , Steltenpohl Pavol , Graczová Elena 
Published: January 2012

AbstractInfluence of model complexity on the separation equipment performance was investigated. As an example, separation of azeotrope formed by 2-methoxy-2-methylpropane and methanol was considered using butan-1-ol as an extractive solvent. Non-equilibrium model of a column for extractive distillation accounting for the mass and heat transfer rates was composed according to the rigorous Maxwell-Stefan theory. An empirical AICHE correlation was adopted for the calculation of binary mass transfer coefficients at column trays. Results of the column steady-state operation were compared with those obtained assuming different equilibrium models. Effect of the quality of the vapor-liquid equilibrium (VLE) description on the results of the separation simulation considering real behavior of either liquid or both equilibrium phases was tested. Real behavior of the liquid phase was computed according to the NRTL equation taking into account binary and, in some cases, also ternary equilibrium data. In case of real behavior of the vapor phase, the equation of state in the form of virial expansion was employed. Qualitative agreement was found comparing the simulation results calculated by equilibrium and non-equilibrium models of the extractive distillation column while using the same description of ternary VLE.
Message Based Analysis on Signaling System Number 7 and its Comparison with Multi-Frequency Coded Signaling
Authors: Alam Md Shah , Khan Mohammad Rezaul Huque 
Published: January 2012

A message based comparative study between signaling system #7(SS7) and MFC Signaling is done. Here the limitations of SS7 and MFC signaling are also studied. The reasons for the transition from Multi-frequency Coded (MFC) Signaling to SS7 has been discussed. DOI: http://dx.doi.org/10.3329/diujst.v7i1.9582 Daffodil International University Journal of Science and Technology Vol.7(1) 2012 15-19
Frequency Distribution of Bacteria Isolated from Different Industrial Effluents
Authors: Ali Amna , Naseem Fozia 
Published: January 2012

Industrial system involves physical and chemical treatment as well as biological processes. Therefore, waste treatment systems such as the industrial effluents depend on the activities of communities of living organism. In this study, an attempt was made on the identification of the bacterial population involved in different industrial effluents. A total of thirty bacterial strains were isolated from glass, textile and pharmaceutical effluent samples on L.B. agar plates. A few, however, were re-cultured on other recommended media for verification of diagnostic characteristics. Maximum numbers of bacterial species were isolated from textile effluent. The results showed that a gramnegative bacillus with a yellow pigment was considered as a major group of the population. These are also being used in different waste water and metal treatment plants all over the world. Keywords: Bacterial identification; industrial effluents; gram negative. DOI: http://dx.doi.org/10.3329/diujst.v7i1.9644 Daffodil International University Journal of Science and Technology Vol.7(1) 2012 28-33
Effect of Blend Ration of Quality Characteristics of Bamboo/Cotton Blended Ring Spun Yarn
Authors: Prakash C , Ramakrishnan G , Koushik CV 
Published: January 2012

The present study reveals the comparison of physical properties of the bamboo/cotton blended yarn with similar 100 % cotton yarn. The bamboo-cotton blend ratios of each category of yarn (30s, 40s and 50s) were 67:33, 50:50, and 33:67, respectively. For each individual count of yarn, it was observed from the test result that the properties of 50:50/bamboo: cotton blended yarn showed very nearer property to the 100% cotton yarn. For Count (30s), 67:33/bamboo: cotton showed very closer property to the 50:50/bamboo: cotton blended yarn. It was also observed that for each count of yarns, which showed decreasing property with the increase of bamboo in the blend. The quality characters depend upon the ratio of bamboo and cotton in the blend. Keywords: Blending; Yarns; Bamboo/Cotton ratio; Ring spun yarn; Physical Properties DOI: http://dx.doi.org/10.3329/diujst.v7i1.9645 Daffodil International University Journal of Science and Technology Vol.7(1) 2012 34-37
System Level Modeling Methodology of Application Specific Instruction Set Processor (SIP) Using SystemC
Authors: Mukherji Rana , Das Manishita 
Published: January 2012

In recent years, the development of application specific instruction set processors (ASIP) is the exclusive domain of the semiconductor houses and core vendors. This is due to the fact that constructing such architecture is a difficult assignment that needs skilled knowledge in distinct domains: application software development tools, processor hardware implementation, and system integration and verification. To specify the design and implementation of such systems and incorporate the functionality implemented in both hardware and software forms, we are compelled to move on from traditional Hardware Description Languages (HDLs). Since C and C++ are dominant languages used by chip architects, system engineers and software engineers today, we believe that a C++ based approach to hardware modeling is necessary. This will enable codesign, providing a more natural solution to partitioning fuctionality between hardware and software. In this paper, we discuss a design approach of SystemC (a C++ class library) for ASIP at the system-level which provides necessary features for modeling design hierarchy, concurrency and reactivity in hardware. To exemplify and validate the method we employed it to the design of a 32-bit ASIP for Hindi Text-to-Speech Synthesis developed by CEERI, Pilani (INDIA). Keywords: ASIP; System; System Level Design DOI: http://dx.doi.org/10.3329/diujst.v7i1.9647 Daffodil International University Journal of Science and Technology Vol.7(1) 2012 44-49
Structural and Electrical Properties of Silicon Nitride Ceramic
Authors: Hosneara M , Hasnat A , Bhuyan AH 
Published: January 2012

The effects of structural properties on the d.c. and a.c. electrical properties of different weight gain reaction bonded silicon nitride (RBSN) have been studied in this work. The degree of nitridation is assessed by the ‘weight gain’ of the ceramic, the percentage by which the weight is increased in the nitriding reaction. From X-ray diffraction (XRD) patterns, it is observed that a higher degree of nitradation sample has strong α-silicon nitride peaks. Intensity of α-silicon nitride peaks decreases with decreases weight gain. The higher degrees of nitridation, the samples have less significant Si peak. XRD patterns were recorded to calculate the lattice parameters of RBSN. The lattice parameters for three weight gain RBSN samples are found to be a =b = 7.7727 Å, c= 5.6565 Å (26% weight gain), a=b= 7.6272 Å, c= 5.6374 Å (42% weight gain) and a=b=7.6158 Å, c= 5.7732 Å (58.27% weight gain) and are in good agreement with the reported values from XRD patterns. Porosity (%) and surface morphology was observed by SEM. Keywords: Silicon nitride ceramic; electrical properties; structural properties. DOI: http://dx.doi.org/10.3329/diujst.v7i1.9648 Daffodil International University Journal of Science and Technology Vol.7(1) 2012 50-58
Estimation of Optimal Time Step and Compare with of ODE Solver of MATLAB Package of RLC Circuit using Numerical Methods
Authors: Islam Sheikh Md Rabiul 
Published: January 2012

In this paper analysis of a RLC circuit model that has been described optimal time step and minimize of error using numerical method. The goal is to reach the optimal time response due to the input for which optimal output response reaches a minimum error and also compared with ODE solver of MATLAB packages for the different cell (mesh) size of the RLC model. Table is constructed of the model to evaluate optimal time step and also CPU time into the simulation using MATLAB 7.6.0(R2008a).The values of register, capacitor and inductor as well as electromagnetic force are obtained through the mathematical relations of the model. The general analysis of the RLC circuit due to the optimal time step and minimum error is developed after several analysis and operations. The theoretical results show effectiveness of optimized of the model. Keywords: Optimal time step; MATLAB; Trapezoidal; Implicit Euler; Runge-Kutta method; RLC circuit. DOI: http://dx.doi.org/10.3329/diujst.v7i1.9650 Daffodil International University Journal of Science and Technology Vol.7(1) 2012 67-73