bluuebunny/crossref_metadata_2025 huggingface dataset:
Moderate to high levels of exercise are associated with higher resting energy expenditure in community-dwelling postmenopausal women
Authors: Froehle Andrew W. , Hopkins Susan R. , Natarajan Loki , Schoeninger Margaret J.
Published: May 2013

Postmenopausal women experience an age-related decline in resting energy expenditure (REE), which is a risk factor for energy imbalance and metabolic disease. Exercise, because of its association with greater lean tissue mass and other factors, has the potential to mediate REE decline, but the relation between exercise and REE in postmenopausal women is not well characterized. This study tests the hypothesis that exercise energy expenditure (EEE) is positively associated with REE and can counter the effects of age and menopause. It involves a cross-sectional sample of 31 healthy postmenopausal women (aged 49–72 years) with habitual exercise volumes at or above levels consistent with current clinical recommendations. Subjects kept exercise diaries for 4 weeks that quantified exercise activity and were measured for body composition, maximal oxygen uptake, and REE. Multiple regression analysis was used to test for associations between EEE, age, body composition, and REE. There was a significant positive relation between EEE and lean tissue mass (fat-free mass and fat-free mass index). The relation between REE and EEE remained significant even after controlling for lean tissue mass. These results support the hypothesis that exercise is positively associated with REE and can counter the negative effects of age and menopause. They also indicate a continuous relation between exercise and REE across ranges of exercise, from moderate to high. Exercise at levels that are at or above current clinical guidelines might, in part, ameliorate the risk for energy imbalance and metabolic disease because of its positive relation with REE.
Characterizing geotechnical anisotropic spatial variations using random field theory
Authors: Zhu H. , Zhang L.M.
Published: May 2013

In this study, anisotropic heterogeneous geotechnical fields are characterized using random field theory, in which five basic patterns of material anisotropy are simulated including isotropy, transverse anisotropy, rotated anisotropy, general anisotropy, and general rotated anisotropy. Theoretical formulations of scale of fluctuation as a function of directional angle are developed for the five basic patterns of anisotropy through modifications of the coordinate system. These formulations of scale of fluctuation are identical for different correlation structures. Correlation functions for the exponential and Gaussian correlation structures are also derived. The matrix decomposition method is then applied to generate anisotropic random fields. The generated random field correlated data are verified with two realizations of transverse anisotropy and general rotated anisotropy random fields. Test values of the sample mean, sample deviation, and scales of fluctuation in six directions match well with the prescribed values. This study provides a technique to characterize inherent geotechnical variability and anisotropy, which is required to realistically simulate complex geological properties in engineering reliability analysis and design.
Toxicity profile of aromatic compounds towards Scenedesmus obliquus: a QSAR study
Authors: Islam Nasarul , Pandith Altaf Hussain
Published: May 2013

The parameterization of molecular hydrophobicity and electrophilicity, contributing to the overall toxicity of aromatic compounds, has been the subject of many quantitative structure−activity relationship (QSAR) studies. So far, hydrophobicity has been largely described in terms of the logarithm of the octanol−water partition coefficient (log P) and the molecular electrophilicity in terms of the energy of the lowest unoccupied molecular orbital (ELUMO), the maximum acceptor superdeocalizability (Amax), and the electrophilicity index (ω). Here, we report for the first time the parameterization of these properties in terms of cumulative interplay of multiple descriptors. The toxicity data of 68 compounds were compiled in terms of 50% population growth inhibition (pIGC50) of Scenedesmus obliquus. The comparison of the two QSARs (pIGC50 = 0.175ELUMO + 0.057log P + 0.363ω + 0.019V – 3.292, R2adj = 0.761 and pIGC50 = 0.368ELUMO + 0.146α + 0.258ω + 0.021V − 1.170, R2adj = 0.776) reveals that polarizability (α) is a superior descriptor to log P for parameterization of hydrophobicity, when used in conjunction with ELUMO, ω, and V, for profiling of the toxicity of the test compounds. The overall results indicate that ω and α are better descriptors of electrophilicity and hydrophobicity, respectively, for mapping the toxicity profile of aromatic derivatives towards the target organism.
Potential of UltraCamX stereo images for estimating timber volume and basal area at the plot level in mixed European forests
Authors: Straub Christoph , Stepper Christoph , Seitz Rudolf , Waser Lars T.
Published: May 2013

Current technical advances in the field of digital photogrammetry demonstrate the great potential of automatic image matching for deriving dense surface measurements of the forest canopy. In contrast to airborne laser scanning (ALS), aerial stereo images are updated more regularly by national or regional mapping agencies in several countries. Frequently, ALS-based terrain models (DTMs) are available, and thus photogrammetric canopy heights can be derived. However, currently, there is little knowledge as to how accurately forest attributes can be modeled using the aerial stereo images acquired by these official, regular aerial surveys, especially for mixed forests in central Europe. Thus, a photogrammetric point cloud derived from UltraCamX stereo images in combination with an ALS-DTM and a classification of coniferous and deciduous tree regions (based on orthoimages) was used to create a stratified estimation of timber volume and basal area in a mixed forest in Germany. Suitable models were derived at the plot level using explanatory variables from the photogrammetric point cloud (which was normalized using an ALS-DTM). The prior stratification of conifer- and deciduous-dominated field plots slightly improved the estimation accuracy. The results verify that stereo images can be an alternative to ALS data for modeling key forest attributes, even in mixed central European forests with complex structure.
Kalpaamruthaa modulates oxidative stress in cardiovascular complication associated with type 2 diabetes mellitus through PKC-β/Akt signaling
Authors: Latha Raja , Shanthi Palanivelu , Sachdanandam Panchanadham
Published: May 2013

This study aimed at investigating the efficacy of Kalpaamruthaa (KA) on cardiovascular damage (CVD) associated with type 2 diabetes mellitus in experimental rats by reducing oxidative stress and the modulation of the protein kinase C-β (PKC-β)/Akt signaling pathway. CVD-induced rats were treated with KA (200 mg·(kg body mass)–1·(day)–1) orally for 4 weeks. KA effectively reduced insulin resistance with alterations in blood glucose, hemoglobin, and glycosylated hemoglobin in CVD-induced rats. Elevated levels of lipids in CVD-induced rats were decreased upon KA administration. In CVD-induced rats the levels of lipoproteins were returned to normal by KA treatment. KA effectively reduced the lipid peroxidative product and protein carbonyl content in liver of CVD-induced rats. KA increased the activities and (or) levels of enzymatic and nonenzymatic antioxidants in liver of CVD-induced rats. KA treatment reduced the fatty inclusion and mast cell infiltration in liver of CVD-induced rats. Further, treatment with KA reduced the chromatin condensation and marginization in myocardium of CVD-induced rats. KA alters insulin signaling by decreasing PKC-β and increasing p-Akt and GLUT4 expressions in heart of CVD-induced rats. The above findings suggest that KA renders protection against CVD induced by type 2 diabetes mellitus by augmenting the cellular antioxidant defense capacity and modulating PKC-β and the p-Akt signaling pathway.
REAL HYPERSURFACES WITH ISOMETRIC REEB FLOW IN COMPLEX QUADRICS
Authors: BERNDT JURGEN , SUH YOUNG JIN
Published: May 2013

We classify real hypersurfaces with isometric Reeb flow in the complex quadrics Qm = SOm+2/SOmSO2, m ≥ 3. We show that m is even, say m = 2k, and any such hypersurface is an open part of a tube around a k-dimensional complex projective space ℂPk which is embedded canonically in Q2k as a totally geodesic complex submanifold. As a consequence, we get the non-existence of real hypersurfaces with isometric Reeb flow in odd-dimensional complex quadrics Q2k+1, k ≥ 1. To our knowledge the odd-dimensional complex quadrics are the first examples of homogeneous Kähler manifolds which do not admit a real hypersurface with isometric Reeb flow.
CONVERGENCE OF FUBINI–STUDY CURRENTS FOR ORBIFOLD LINE BUNDLES
Authors: COMAN DAN , MARINESCU GEORGE
Published: May 2013

We discuss positive closed currents and Fubini–Study currents on orbifolds, as well as Bergman kernels of singular Hermitian orbifold line bundles. We prove that the Fubini–Study currents associated to high powers of a semipositive singular line bundle converge weakly to the curvature current on the set where the curvature is strictly positive, generalizing a well-known theorem of Tian. We include applications to the asymptotic distribution of zeros of random holomorphic sections.
Rhein Inhibits the Expression of Vascular Cell Adhesion Molecule 1 in Human Umbilical Vein Endothelial Cells with or without Lipopolysaccharide Stimulation
Authors: Hu Gang , Liu Jiang , Zhen Yong-Zhan , Wei Jie , Qiao Yue , Lin Ya-Jun , Tu Ping
Published: May 2013

Reducing the expression of endothelial cell adhesion molecules (ECAMs) is known to decrease inflammation-induced vascular complications. In this study, we explored whether rhein can reduce the inflammation-induced expression of ECAMs in human umbilical vein endothelial cells (HUVECs) with or without lipopolysaccharide (LPS) stimulation. HUVECs were treated with different concentrations of rhein with or without 2.5 μg/ml LPS stimulation. Cell viability was assayed using the MTT method. Real-time PCR and Western blot analysis were used to measure the transcription and expression levels of ECAMs, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-SELECTIN and related signaling proteins. The results indicated that rhein (0–20 μmol/L) and LPS (0–10 μg/ml) had no effect on the viability of HUVECs. LPS could promote the expression of VCAM-1, ICAM-1 and E-SELECTIN. Rhein appeared to target VCAM-1, ICAM-1 and E-SELECTIN, with the transcription and expression of all three factors being reduced by the rhein treatment (10 and 20 μmol/L). The transcription and expression of VCAM-1 were also reduced by treatment with rhein (10 and 20 μmol/L) in the presence of LPS stimulation. In conclusion, rhein treatment reduced the expression of VCAM-1 in HUVECs via a p38-dependent pathway.
Triterpenoid-Rich Fraction from Ilex hainanensis Merr. Attenuates Non-Alcoholic Fatty Liver Disease Induced by High Fat Diet in Rats
Authors: Cui Wei-Xi , Yang Jie , Chen Xiao-Qing , Mao Qian , Wei Xiang-Lan , Wen Xiao-Dong , Wang Qiang
Published: May 2013

Non-alcoholic fatty liver disease (NAFLD) has become a major challenge to the healthcare system. This study was designed to evaluate the effect of the triterpenoid-rich fraction (TF) from Ilex hainanensis Merr. on NAFLD. Male Sprague-Dawley (SD) rats were fed a normal diet (control) or high fat diet (NAFLD model). After four weeks, the high fat diet group was orally administrated TF (250 mg/kg) for another two weeks. High fat diet fed rats displayed hyperlipidemia and a decline in liver function compared with control. However, administration with TF could effectively improve these symptoms, as demonstrated by decreasing the plasma levels of triglyceride (p <0.05), total cholesterol (p < 0.01), low-density lipoprotein cholesterol (p < 0.05), alanine transaminase (p < 0.05), aspartate aminotransferase (p < 0.01), liver index (p < 0.05) and insulin resistance index (p < 0.05) while increasing the high-density lipoprotein cholesterol (p < 0.05). Meanwhile, histopathological examination of livers also showed that TF could reduce the incidence of liver lesions induced by high fat diet. Furthermore, TF could alleviate oxidative stress and inflammation status indicated by the decline malondialdehyde and superoxide dismutase levels (p < 0.01, both) and levels of interleukin 6 and tumor necrosis factor-α (p < 0.05). In addition, immunohistochemistry showed TF evidently elevated the peroxisome proliferator-activated receptor (PPARα) expression (p < 0.01), while it diminished the Cytochrome P450 2E1 (CYP2E1) expression (p < 0.01) in liver. These results demonstrate that TF has potential ability to protect liver against NAFLD by regulating lipids metabolism and alleviating insulin resistance, inflammation and oxidative stress. This effect might be associated with regulating PPARα and CYP2E1 expression.
ONE-RELATOR QUOTIENTS OF GRAPH PRODUCTS
Authors: ANTOLÍN YAGO , KAR ADITI
Published: May 2013

In this paper, we generalize Magnus' Freiheitssatz and solution to the word problem for one-relator groups by considering one-relator quotients of certain classes of right-angled Artin groups and graph products of locally indicable polycyclic groups.
DOUBLE COSETS IN FREE GROUPS
Authors: FRENKEL ELIZAVETA , REMESLENNIKOV VLADIMIR N.
Published: May 2013

In this paper, we study double cosets of finite rank free groups. We focus our attention on cancellation types in double cosets and their formal language properties.
BANDED SURFACES, BANDED LINKS, BAND INDICES AND GENERA OF LINKS
Authors: KIM DONGSEOK , KWON YOUNG SOO , LEE JAEUN
Published: May 2013

Every link is shown to be presentable as a boundary of an unknotted flat banded surface. A (flat) banded link is defined as a boundary of an unknotted (flat) banded surface. A link's (flat) band index is defined as the minimum number of bands required to present the link as boundaries of an unknotted (flat) banded surface. Banded links of small (flat, respectively) band index are considered here. Some upper bounds are provided for these band indices of a link using braid representatives and canonical Seifert surfaces of the link. The relation between the band indices and genera of links is studied and the band indices of pretzel knots are calculated.
RECEPTOR-DEPENDENT SENSITIVITY OF NF-κB TO LOW PHYSIOLOGICAL LEVEL
Authors: YANG PANPAN , ZHOU TIANSHOU
Published: May 2013

In the NFκB signaling pathway, cells respond to different concentrations of the TNFα signal by means of NFκB transcription factors. Previous studies showed that most cells are activated under high-dose stimulations and NFκB activation results in oscillations in nuclear NFκB abundance. Here, by analyzing sensitivity gain for the response of the nuclear NFκB to the number of cell-surface receptors under low-dose stimulations, we show that changes in the receptor number can give rise to significant changes in the nonsaturation part of the dose–response curve, where the receptor activation rates are very sensitive to stimulations. In addition, the number of the activated receptors tends to increase in a large range of stimulation dose and can significantly influence the expression of the downstream genes. These results imply that the number of cell-surface receptors plays a role of information encoding like frequency or amplitude encoding described in previous studies.
UNDERSTANDING THE MOLECULAR MECHANISM OF BINDING MODES OF AURORA A INHIBITORS BY LONG TIME SCALE GPU DYNAMICS
Authors: FU TING , WU XUE , XIU ZHILONG , WANG JINGUANG , YIN LIU , LI GUOHUI
Published: May 2013

Inhibition of Aurora A kinase interaction is considered to be a promising approach for the discovery of new molecularly targeted cancer therapeutics. In this study, the binding mechanisms of two different inhibitors with a contrasting binding affinity to Aurora A were investigated by long time scale GPU molecular dynamics (MD) simulations coupled with molecular mechanics-Poisson–Boltzmann/generalized Born surface area (MM-PB/GBSA) method. The results showed that the predicted binding free energies of these two complexes were consistent with the experimental data. Through analyzing the individual energy components of binding free energy, we found that the van der Waals contribution was the main force to drive the inhibitor–protein binding and the electrostatic contribution was also a crucial factor for the inhibitor–Aurora A binding. The structural analysis demonstrated that the inhibitor HPM could produce more hydrophobic interaction contacts with Aurora A than that of 2JZ, and the loss of key hydrogen bonds between the inhibitor and residue Arg137 in the hinge region of Aurora A was another important reason for the weaker binding affinity of 2JZ to Aurora A. This study sheds more light on the development of the efficient inhibitors targeting the Aurora A.
A FAST AND ACCURATE ALGORITHM FOR DIPLOID INDIVIDUAL HAPLOTYPE RECONSTRUCTION
Authors: WU JINGLI , LIANG BINBIN
Published: May 2013

Haplotypes can provide significant information in many research fields, including molecular biology and medical therapy. However, haplotyping is much more difficult than genotyping by using only biological techniques. With the development of sequencing technologies, it becomes possible to obtain haplotypes by combining sequence fragments. The haplotype reconstruction problem of diploid individual has received considerable attention in recent years. It assembles the two haplotypes for a chromosome given the collection of fragments coming from the two haplotypes. Fragment errors significantly increase the difficulty of the problem, and which has been shown to be NP-hard. In this paper, a fast and accurate algorithm, named FAHR, is proposed for haplotyping a single diploid individual. Algorithm FAHR reconstructs the SNP sites of a pair of haplotypes one after another. The SNP fragments that cover some SNP site are partitioned into two groups according to the alleles of the corresponding SNP site, and the SNP values of the pair of haplotypes are ascertained by using the fragments in the group that contains more SNP fragments. The experimental comparisons were conducted among the FAHR, the Fast Hare and the DGS algorithms by using the haplotypes on chromosome 1 of 60 individuals in CEPH samples, which were released by the International HapMap Project. Experimental results under different parameter settings indicate that the reconstruction rate of the FAHR algorithm is higher than those of the Fast Hare and the DGS algorithms, and the running time of the FAHR algorithm is shorter than those of the Fast Hare and the DGS algorithms. Moreover, the FAHR algorithm has high efficiency even for the reconstruction of long haplotypes and is very practical for realistic applications.
ON NORDEN STRUCTURES ON NEUTRAL 4-MANIFOLDS WITH ALMOST PARACOMPLEX STRUCTURES
Authors: ISCAN MURAT
Published: May 2013

We construct some Norden metrics on a pseudo-Riemannian 4-manifold of neutral signature (+ + - -) with respect to some compatible paracomplex structures. Also, we present some examples.
KERR–NEWMAN BLACK HOLES IN f(R) THEORIES
Authors: CEMBRANOS J. A. R. , DE LA CRUZ-DOMBRIZ A. , ROMERO P. JIMENO
Published: May 2013

In the context of f(R) modified gravity theories, we study the Kerr–Newman black hole solutions. We study nonzero constant scalar curvature solutions and discuss the metric tensor that satisfies the modified field equations. We conclude that, in the absence of a cosmological constant, the black holes (BHs) existence is determined by the sign of a parameter h dependent of the mass, the charge, the spin and the scalar curvature. Different values of this parameter lead to diverse astrophysical objects, such as extremal and marginal extremal BHs. Thermodynamics of BHs are then studied, as well as their local and global stability. We analyze these features in a large variety of f(R) models. We remark the main differences with respect to general relativity and show the rich thermodynamical phenomenology that characterizes this framework.
ROTATING WAVE APPROXIMATION OF THE LAW'S EFFECTIVE HAMILTONIAN ON THE DYNAMICAL CASIMIR EFFECT
Authors: FUJII KAZUYUKI , SUZUKI TATSUO
Published: May 2013

In this paper, we treat the Law's effective Hamiltonian of the dynamical Casimir effect (DCE) in a cavity and construct an analytic approximate solution of the time-dependent Schrödinger equation under the general setting through a kind of rotating wave approximation (RWA). To the best of our knowledge this is the finest analytic approximate solution.
Lanthanide macrocyclic complexes: from molecules to materials and from materials to devices
Authors: Bouvet Marcel , Gaudillat Pierre , Suisse Jean-Moïse
Published: May 2013

In the present review, we show how the chemistry of lanthanide macrocyclic complexes, which began almost 50 years ago in Russia, is still very active. Additionally to bisphthalocyanines complexes, triple-decker, but also quadruple- and quintuple-decker complexes have been synthesized via new chemical routes. The driving force for the development of this chemistry arises from the wide range of possible applications. Owing to their very high conductivity, compared to that of monophthalocyanines, LnPc2 and Ln2Pc3 complexes are used as molecular semiconductors in electronic devices. The radical nature of LnPc2 complexes makes them easily oxidized and reduced. This is the reason why they are particularly promising materials for the development of new chemical sensors, associated with both conductimetric and optical transducers.
Magnetic removal of nitrate ions from aqueous solution using amino-silica coated magnetic nanoparticles modified by oxovanadium(IV) porphyrin
Authors: Poursaberi Tahereh , Karimi Maryam , Hassanisadi Mostafa , Sereshti Hassan
Published: May 2013

In this study, we have treated nitrate contaminated groundwater using modified magneticnanoparticles. The modification of magnetite nanoparticles were conducted by 3-aminopropyl-triethoxysilane followed by oxovanadium(IV) porphyrin in order to enhance the removal of nitrate ions. Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM) were used to characterize the synthesized nanoparticles. The effect of pH, contact time, sorbent dosage and some co-existing anions present in aqueous solutions were investigated. The isothermal data of nitrate sorption conformed well to the Langmuir model and the maximum sorption capacity of nanosorbent for nitrate was 76.92 mg.g-1. Thermodynamic study indicated that the adsorption is endothermic and spontaneous. Regeneration of nitrate adsorbed material could be be possible by NaOH and the modified magnetic nanoparticles exhibited good reusability. The proposed system can provide a fast and efficient removal of the nitrate ion by using just an external magnetic field. The competitive adsorption tests verified that, this system has good adsorption selectivity for nitrate ions.
IMPROVEMENT OF THE PEELING STRENGTH OF THIN FILMS BY A BIOINSPIRED HIERARCHICAL INTERFACE
Authors: ZHAO HONG-PING , WANG YECHENG , LI BING-WEI , FENG XI-QIAO
Published: May 2013

The peeling behavior of a thin film bonded to a substrate is investigated by using the cohesive interface model. We compare the peeling processes of film/substrate interfaces with three different geometric shapes, including a flat interface, a curved interface of sinusoidal shape, and a wavy interface with two-level sinusoidal hierarchy. The effect of the peeling angle on the maximal peeling strength is also examined. It is demonstrated that the peeling strength can be significantly improved by introducing a hierarchical wavy morphology at the film/substrate interface. This study may be helpful for the design of film/substrate systems with enhanced mechanical properties.
ISOGEOMETRIC SIMULATION FOR BUCKLING, FREE AND FORCED VIBRATION OF ORTHOTROPIC PLATES
Authors: VALIZADEH N. , BUI T. Q. , VU V. T. , THAI H. T. , NGUYEN M. N.
Published: May 2013

Buckling, free and forced vibration analyses of orthotropic plates are studied numerically using Isogeometric analysis. The present formulation is based on the classical plate theory (CPT) while the NURBS basis function is employed for both the parametrization of the geometry and the approximation of plate deflection. An efficient and easy-to-implement technique is used for imposing the essential boundary conditions. Numerical examples for free and forced vibration and buckling of orthotropic plates with different boundary conditions and configurations are considered. The numerical results are compared with other existing solutions to show the efficiency and accuracy of the proposed approach for such problems.
ON THE ORDERS OF EVEN K-GROUPS OF RINGS OF INTEGERS IN CYCLOTOMIC ℤp-EXTENSIONS OF ℚ
Authors: KITAJIMA TAKAHIRO
Published: May 2013

Let p be a prime number, and let 𝔹p,n be the nth layer in the cyclotomic ℤp-extension of ℚ with ring of integers [Formula: see text]. In this paper we show that for each even integer m ≥ 2 and each prime number p the orders of the Quillen K-groups [Formula: see text] are unbounded, and that there are in fact infinitely many different prime numbers dividing the order of [Formula: see text] for some n.
EICHLER ORDERS, TREES AND REPRESENTATION FIELDS
Authors: ARENAS-CARMONA LUIS
Published: May 2013

The spinor class field for a genus of orders of maximal rank in a quaternion algebra 𝔄 over a number field K is an abelian extension Σ/K provided with a distance function associating elements of the corresponding Galois group to pairs of orders in that genus. If ℌ ⊆ 𝔇 are two orders in a quaternion algebra 𝔄 with 𝔇 of maximal rank, the representation field F = F(𝔇 | ℌ) is a subfield of the spinor class field for the genus of 𝔇 such that, the set of spinor genera of orders in that genus representing the order ℌ, coincides with the set of spinor genera of orders whose distance to 𝔇 fixes F pointwise. Previous works have focused on two cases: maximal orders 𝔇 and commutative orders ℌ. In this work, we give a method to compute the representation field F(𝔇|ℌ) when 𝔇 is the intersection of a finite family of maximal orders, e.g., an Eichler order, and ℌ is arbitrary. Examples are provided.
KUMMER GENERATORS AND TORSION POINTS OF ELLIPTIC CURVES WITH BAD REDUCTION AT SOME PRIMES
Authors: YASUDA MASAYA
Published: May 2013

For a prime p, let ζp denote a fixed primitive pth root of unity. Let E be an elliptic curve over a number field K with a p-torsion point. Then the p-torsion subgroup of E gives a Kummer extension over K(ζp), and in this paper, we study the ramification of such Kummer extensions using the Kummer generators directly computed by Verdure in 2006. For quadratic fields K, we also give unramified Kummer extensions over K(ζp) generated from elliptic curves over K having a p-torsion point with bad reduction at certain primes. Many of these unramified Kummer extensions have not appeared in the previous work using fundamental units of quadratic fields.
INDEX-DEPENDENT DIVISORS OF COEFFICIENTS OF MODULAR FORMS
Authors: MORIYA B. K. , SMYTH C. J.
Published: May 2013

We evaluate [Formula: see text] for a certain family of integer sequences, which include the Fourier coefficients of some modular forms. In particular, we compute [Formula: see text] for all positive integers n for Ramanujan's τ-function. As a consequence, we obtain many congruences — for instance that τ(1000m) is always divisible by 64000. We also determine, for a given prime number p, the set of n for which τ(pn-1) is divisible by n. Further, we give a description of the set {n ∈ ℕ : n divides τ(n)}. We also survey methods for computing τ(n). Finally, we find the least n for which τ(n) is prime, complementing a result of D. H. Lehmer, who found the least n for which |τ(n)| is prime.
THE SETS OF DIFFERENT CONTINUED FRACTIONS WITH THE SAME PARTIAL QUOTIENTS
Authors: ZHONG TING , TANG LIANG
Published: May 2013

Let B = {bn, n ≥ 1} be a strictly increasing sequence of natural numbers, let an(x) and en(x) be the nth partial quotients of regular and Engel continued fraction of x, respectively. Define [Formula: see text] In this paper, we show that if the sequence B = {bn}n≥1 grows to infinity in a moderate speed, then [Formula: see text] However, a counterexample is also provided indicating that if {bn}n≥1 grows to infinity extremely fast, the above dimensional relation fails.
THE NON-CYCLOTOMIC PART OF f(x)xn+ g(x) AND ROOTS OF RECIPROCAL POLYNOMIALS OFF THE UNIT CIRCLE
Authors: DOBROWOLSKI E. , FILASETA M. , VINCENT A. F.
Published: May 2013

Given relatively prime polynomials f(x) and g(x) in ℤ[x] with non-zero constant terms, we show that for n greater than an explicitly determined bound depending on f(x) and g(x), if the polynomial f(x)xn+ g(x) is non-reciprocal, then its non-cyclotomic part is irreducible except for some explicit cases where a known factorization of f(x)xn+ g(x) can easily be described. Prior work of a similar nature is discussed which shows under similar circumstances the non-reciprocal part off(x)xn+ g(x) is irreducible. The current paper establishes and makes use of a result which shows that a reciprocal polynomial f(x) with a root off the unit circle must have a root bounded away from the unit circle by an explicitly given function of the degree of f(x), the leading coefficient a of f(x) and the discriminant of f(x). Notably in this result, a need not be 1.
SYNTHESIS OF MESOPOROUS OF NyTi1–xCexO2–y STRUCTURES AND ITS VISIBLE LIGHT INDUCED PHOTOCATALYTIC PERFORMANCE
Authors: RANGEL R. , GARCÍA-ESPINOZA J. D. , ESPITIA I. , QUINTANA P. , BARTOLO-PÉREZ P. , ALVARADO-GIL J. J. , TREJO-TZAB R.
Published: May 2013

The present work was addressed to study the visible light induced performance as photocatalysts of mesoporous N y Ti 1–x Ce x O 2–y structures obtained under microwave irradiation. The titanium dioxide ( TiO 2) was doped with cerium and nitrogen in order to improve the quantum efficiency of the TiO 2 and to shift its adsorption spectra to the visible region. The prepared meso-powders were analyzed by means of X-ray diffraction (XRD), scanning Electron microscopy (SEM), infrared (IR) spectroscopy, transmission electronic microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The surface area was evaluated by means of the Brunauer-Emmett-Teller (BET) method and ultraviolet (UV)-visible diffuse reflectance measurements were performed in order to determine the band gap energy. In addition, the photocatalytic activity of the samples was evaluated by monitoring the photodegradation of methylene blue (MB) under UV and visible light energy irradiation. The results show that our methodology is an effective way for incorporating cerium and nitrogen into TiO 2 compound, which in turn, increases its photocatalytic activity. The diffuse reflectance analysis confirms that the absorption edge was shifted towards the visible region of the optical spectrum. The XRD diffraction patterns indicate homogeneous solid solutions in which prevails the anatase phase. It was observed a reduction in crystal size from 13.1 nm to 7.7 nm for N y Ti 0.98 Ce 0.02 O 2–y in comparison to TiO 2. The textural properties of the synthesized compounds were determined, by means of adsorption isotherms indicating the formation of mesoporous structures. IR spectra show characteristic vibration signals attributed to Ti–O–Ti bonds, as well as vibrations assigned to cerium and nitrogen bonds. The XPS analyses evidence the presence of Ce 3+/ Ce 4+ redox couple and Ti–N bonds. The photocatalityc efficiency was evaluated in the degradation of MB monitoring the absorbance change at 664 nm. The degradation of this compound was 91.4% using N y Ti 0.98 Ce 0.02 O 2–y as photocatalyst under UV energy in 90 min. Also 38.7% of MB degradation was achieved in 150 min under visible light radiation.
OVERTAKING OPTIMAL HARVESTING FOR AN AGE-DEPENDENT n-DIMENSIONAL FOOD CHAIN MODEL
Authors: LUO ZHIXUE , ZHANG HUI , ZHANG YONGCHENG
Published: May 2013

This paper is concerned with an optimal harvesting problem over an infinite horizon for age-dependent n-dimensional food chain model and the analysis of long-term behaviors of the optimal-controlled system. The existence of overtaking optimal policy is proved and a maximum principle is carefully derived by means of Dubovitskii–Milyutin functional analytical extremum theory. Weak and strong turnpike properties of optimal trajectories are established.
SPREADING DYNAMICS OF A DISEASE-AWARENESS SIS MODEL ON COMPLEX NETWORKS
Authors: LIN BEI , SUN ZHENLONG , FU XINCHU , ZHU GUANGHU
Published: May 2013

In this paper, to better understand the impact of awareness and the network structure on epidemic transmission, we divide the population into four subpopulations corresponding to different physical states and conscious states, and we first propose a modified disease-awareness model, then verify the global stability of the disease-free and endemic equilibria, and finally present numerical simulations to demonstrate the theoretical analysis. By examining the spreading influences of model parameters, we find that the outbreak scale can be effectively controlled through increasing the spread rate of awareness or reducing the rate of awareness loss. That is to say, all sorts of media publicity are meaningful. Meanwhile, we find that infection will be affected by consciousness through the control variable.
THE GREEN PHOSPHOR SrAl2O4:Eu2+, R3+ (R=Y, Dy) AND ITS APPLICATION IN ALTERNATING CURRENT LIGHT-EMITTING DIODES
Authors: CHEN LEI , ZHANG YAO , XUE SHAOCHAN , DENG XIAORONG , ANQI  , LUO  , LIU FAYONG , JIANG YANG , CHEN SHIFU , BAHADER ALI
Published: May 2013

The aim of the present investigation was to develop a phosphor to solve the flickering luminescence of alternating current (AC) light-emitting diodes (LED) by compensating the dark duration with appropriately persistent luminescence. The phosphor SrAl 2 O 4: Eu 2+ co-doped with Y 3+ or Dy 3+ was synthesized via solid-state reaction with H 3 BO 3 as flux. The crystal structure and morphology were characterized by using X-ray diffraction (XRD) and Scanning Electron Microscope (SEM), respectively. The photoluminescence spectra were collected with a fluorescence spectrometer. The results demonstrated that appropriate amount of Y 3+ or DY 3+ doped was beneficial to suppress the by-product of Sr 4 Al 14 O 25 which easily co-existed with the SrAl 2 O 4 phase brought by the flux of H 3 BO 3. However, too much Y 3+ or DY 3+ doped resulted in the formation of another impurity phase, i.e., the yttrium aluminum garnet of Y 3 Al 5 O 12 and Dy 3 Al 5 O 12. Comparatively, the doped DY 3+ was more helpful in prolonging the persistent luminescence, while Y 3+ was more efficient in enhancing luminescence intensity. To demonstrate the feasibility of the phosphor applied in AC LEDs, a nearly white AC LED was fabricated by coating the phosphor on a blue AC LED chip. The persistent luminescence was radiated from the AC LED device after turning power off. Moreover, the effect of the phosphor on compensating the AC LED dark duration through persistent luminescence was revealed by using the Keyence VW-9000 High-speed Microscope for the first time.
AN EXPERIMENTAL STUDY ON THE PERFORMANCE OF RADIANT FLOOR COOLING MODULES
Authors: CHIEN K. C. , CHUAH Y. K. , CHANG W. T.
Published: May 2013

This study investigates experimentally the performance of radiant floor cooling modules. Different radiant cooling modular units with embedded chilled water piping were tested for cooling performance. The effects of pipe pitch and also the effects of extended fins were tested. The results of the experiments show that the modular design of radiant floor used has low heat resistance between the chilled water and the radiant cooling surface. Mean radiant temperature was analyzed to measure the cooling comfort performance. An increase of radiant cooling surface area was found to be important for effective radiant heat exchange. Moreover, the larger the temperature difference between the radiant surface and the walls, higher rate of radiant cooling can be achieved. The cooling intensity in terms of per unit area was tested to be as high as 60 W/m2. In conclusion the radiant floor cooling modular units are effective to remove sensible heat and provide comfort cooling. In practice it can be supplemented with lower humidity outdoor air supply for the removal of latent heat.
DIELECTRIC BEHAVIOR OF NANO BARIUM TITANATE FILLED POLYMERIC COMPOSITES
Authors: PRATAP A. , JOSHI N. J. , RAKSHIT P. B. , GREWAL G. S. , SHRINET V.
Published: May 2013

Rapid growth of electronic industry requires development of new materials that combine the high dielectric constant intrinsic to ferroelectric ceramic materials with easy processing characteristics of polymers. Ceramic-polymeric composites possess interesting properties for a variety of electronic applications including passive electronic devices. In fact, polymer-ceramic materials have drawn lot attention for use in microelectronic packaging, because they can give higher performance with lower cost, size and weight.

In this work, attempts are made to prepare ceramic polymer composites followed by characterization of dielectric properties. The Barium Titanate ceramic powders are synthesized using the hydrothermal process. Crystal structure and crystallite size of particles are determined using X-ray diffraction. Silane treatment is carried out on Barium Titanate powder to increase its compatibility with polymer, followed with preparation of ceramic polymer composites. Epoxy and polyvinyledene fluoride (PVDF) polymers are used as matrices for preparation of the composites. The proportion of nanopowder is varied from 60 to 90 wt%. Dielectric properties such as volume resistivity, dielectric constant, dissipation factor are evaluated. Results indicate that the dielectric constant and dissipation factor vary between 18 -140 and 0.01 to 0.09, respectively as the relative ratio of polymer and silane modified Barium Titanate is varied. Specifically, at 90 wt% of 0.1 wt% silane modified Barium Titanate, the highest dielectric constant of 140 along with dissipation factor of 0.07 is obtained in the epoxy based system.
SCIENTIFIC APPROACH TO RENEWABLE ENERGY THROUGH SOLAR CELLS
Authors: RAO M. C.
Published: May 2013

Renewable energy is increasingly viewed as critically important globally. Solar cells convert the energy of the sun into electricity. The method of converting solar energy to electricity is pollution free, and appears a good practical solution to the global energy problems. Energy policies have pushed for different technologies to decrease pollutant emissions and reduce global climate change. Photovoltaic technology, which utilizes sunlight to generate energy, is an attractive alternate energy source because it is renewable, harmless and domestically secure. Transparent conducting metal oxides, being n-type were used extensively in the production of heterojunction cells using p-type Cu 2 O . The long held consensus is that the best approach to improve cell efficiency in Cu 2 O -based photovoltaic devices is to achieve both p- and n-type Cu 2 O and thus p-n homojunction of Cu 2 O solar cells. Silicon, which, next to oxygen, is the most represented element in the earth's crust, is used for the production of monocrystalline silicon solar cells. Silicon is easily obtained and processed and it is not toxic and does not form compounds that would be environmentally harmful. In contemporary electronic industry silicon is the main semiconducting element. Thin-film cadmium telluride (CdTe) solar cells are the basis of a significant technology with major commercial impact on solar energy production. Polycrystalline thin-film solar cells such as CuInSe 2 (CIS), Cu (In, Ga) Se 2 (CIGS) and CdTe compound semiconductors are important for terrestrial applications because of their high efficiency, long-term stable performance and potential for low-cost production. Highest record efficiencies of 19.2% for CIGS and 16.5% for CdTe have been achieved.
SYNTHESIS AND PHOTOSENSITIVE PERFORMANCE OF NANOSTRUCTURED ZnO/DYE HYBRID FILM FOR ENERGY CONVERSION
Authors: RANI MAMTA , TRIPATHI S. K.
Published: May 2013

The ZnO film prepared by doctor blade method are highly porous in presence of structure directing agent PEG and then can be easily sensitized by various molecules. In the present work, the nanostructured ZnO /dye hybrid film prepared by doctor blade method has been investigated in conductivity and photoconductivity measurements in view of applications in dye-sensitized solar cells (DSSC) and in optoelectronics, since electron transport in these devices plays a decisive role for the electron collection efficiency and therefore for the overall efficiency. The absorption of ZnO film sensitized by Rose Bengal dye (RB) has been studied by UV spectroscopy which indicates that after the dye is adsorbed on the ZnO electrode, its absorption spectra showed red-shift in the peak position compared to the absorbance spectra of dye in ethanol. Highly porous ZnO films are found to have high dark conductivity, probably because of a higher n-doping, which is due to higher concentration of Zn atoms in the film. On the other hand, ZnO /RB hybrid film is found to show a much higher sensitivity to illumination with visible light in photoconductivity measurements due to a higher absolute photoconductivity and lower conductivity in the dark.
THEORETICAL PREDICTION OF ELASTIC CONSTANTS FOR MgO
Authors: PANDEY B. K. , PANDEY ANJANI K. , SINGH CHANDRA KUMAR
Published: May 2013

Precise knowledge of the elastic properties of MgO periclase, under high-pressure condition is therefore crucial for constructing the accurate mineralogical model of the Earth's lower mantle. In present work an attempt has been done to calculate the pressure dependence elastic properties such as isothermal bulk modules (KT), Young's modulus of elasticity Y and shearing stress G for geophysical MgO by using three deferent phenomenological EOS viz. the Born-Mayer EOS, Murnaghan EOS and Birch EOS. The result shows that the value of elastic parameter as calculated by using Murnughan EOS and Birch EOS shows close agreement with each other while Born-Mayer EOS shows deviation in calculated values.
SOFT MAGNETIC PROPERTIES OF Mg0.7-xNi0.3ZnxFe2O4 FERRITES SYNTHESIZED BY SOL-GEL AUTO-COMBUSTION TECHNIQUE WITHOUT POST-PREPARATION THERMAL TREATMENT
Authors: GHOSH A. , SATALKAR M. , RATHOD S. , NAG S. P. , VYAS P. , KANE N. , GHODKE N. , PRASAD R. , DWIVEDI R.
Published: May 2013

Single phase nanocrystalline soft magnetic Mg 0.7-x Ni 0.3 Zn x Fe 2 O 4, ferrites with x = 0.0 − 0.7 were prepared by sol gel auto-combustion method. X-ray diffraction confirms the formation of single phase nano-crystalline cubic spinel ferrites with average grain diameter ranging between 12.9 nm to 23.9 nm. Formation of the ferrite phase without subsequent heat treatment makes sol-gel auto combustion technique especially suitable and economical for the large scale industrial production of the nano-crystalline ferrites for multilayer chip inductor applications (MLCI). Both, lattice parameter and X-ray density shows a linear increase with increasing Zn 2+ concentration, attributed to the difference in ionic radii and density of Mg and Zn . Increase in Zn content enhances the soft magnetic behavior, exhibiting linear decrease of coercivity from 122.34 Oe to 72.45 Oe, explained by increase of density with Zn addition. The maximum magnetization (Mmax)increases up to 0.106 Tesla (for x = 0.4) and. then decreases with increase of Zn content, discussed on the basis of increase of the occupancy of A-site in spinel ferrite by non-magnetic Zn 2+ ion.
SYNTHESIS AND CHARACTERIZATION OF IRON OXIDES WITH 2223 SUPERCONDUCTORS
Authors: SINGH H. S. , KUMAR ROHITASH
Published: May 2013

To understand the mechanism and structure of superconductor of type Bi 2 Sr 2 Ca n−1 Cu n O x (n=1,2,3), the great interest has developed in the structure and physical properties of compound with structure formula ( Bi 2 M 1+n TM n O x), where m= Sr,Ba,Ca , and this transition metal other than Cu , so for compound reported belongs to group which contain transition metal such as iron, cobalt, manganese etc. some more study using iron as transition metal is reports for Bi 2 Sr 1+n fe n O 2 for n=2. In the present work we are interested the study of synthesis and characterization of compounds which are isosrtructural to the 2223 Bismuth superconductor. for example Bi 2 Sr 4−x Ca x fe 3−y Cu y O 2 to be synthesis with different amounts by XRD method.
THE TRANSIENT PLANE SOURCE TECHNIQUE TO MEASURE THERMAL CONDUCTIVITY OF CLAYS OF BIKANER REGION
Authors: SHEKHAWAT M. S. , TAK S. K. , MANGAL R.
Published: May 2013

Thermal conductivity and thermal diffusivity of blended clays have been studied with special reference to Ukrainian clay. The blends were made of three different clays available locally in western part of Rajasthan. Thermal conductivity and thermal diffusivity were determined using the transient plane source (TPS) technique at room temperature and normal pressure. It was found that thermal conductivity and thermal diffusivity of the blends reported maximum at temperature 1200° C and near in the values of Ukrainian clay. The thermal conductivity of blend B2 reported maximum value (1.29 W/m-k) in the present study.
MINERALOGICAL CHARACTERIZATION STUDIES ON UNBURNT CERAMIC PRODUCT MADE FROM ROCK RESIDUE ADDITIVES BY FT-IR SPECTROSCOPIC TECHNIQUE
Authors: VIJAYARAGAVAN R. , MULLAINATHAN S. , BALACHANDRAMOHAN M. , KRISHNAMOORTHY N. , NITHIYANANTHAM S. , MURUGESAN S. , VANATHI V.
Published: May 2013

The usability of waste rock (rock residue) powder as an additive material in ceramic samples was investigated. Qualitative analysis was carried out to determine the major and minor constituent minerals present in ceramic bodies made from rock residue powder by using FT-IR spectroscopic technique. Further, the representative ceramic bodies are analyzed by FT-IR technique to yield more information about the functional groups and also to estimate the order or disorder of kaolinite structure.
STUDIES ON VARIOUS FUNCTIONAL PROPERTIES OF TITANIA THIN FILM DEVELOPED ON GLAZED CERAMIC WALL TILES
Authors: ANIL ASHA , DARSHANA R BANGORIA , MISRA S. N.
Published: May 2013

A sol-gel based TiO 2 thin film was applied on glazed wall tiles for studying its various functional properties. Thin film was deposited by spin coating on the substrate and subjected to curing at different temperatures such as 600°C, 650, 700°C, 750°C and 800°C with 10 minutes soaking. The gel powder was characterized by FTIR, DTA/TG and XRD. Microstructure of thin film was analyzed by FESEM and EDX. Surface properties of the coatings such as gloss, colour difference, stain resistance, mineral hardness and wettability were extensively studied. The antibacterial activity of the surface of coated substrate against E. coli was also examined. The durability of the coated substrate in comparison to the uncoated was tested against alkali in accordance with ISO: 10545 (Part 13):1995 standard. FESEM images showed that thin films are dense and homogeneous. Coated substrates after firing results in lustre with high gloss, which increased from 330 to 420 GU as the curing temperature increases compared to that of uncoated one (72 GU). Coated substrate cured at 800°C shows higher mineral hardness (5 Mohs’) compared to uncoated one (4 Mohs’) and films cured at all temperatures showed stain resistance. The experimental results showed that the resistance towards alkali attack increase with increase in curing temperature and alkali resistance of sample cured at 800 °C was found to be superior compared to uncoated substrate. Contact angle of water on coated surface of substrates decreased with increase in temperature. Bacterial reduction percentages of the coated surface was 97% for sample cured at 700°C and it decreased from 97% to 87% as the curing temperature increased to 800 °C when treated with E. coli bacteria.