bluuebunny/crossref_metadata_2025 huggingface dataset:
Smokers’ increased risk for disability pension: social confounding or health-mediated effects? Gender-specific analyses of the Hordaland Health Study cohort
Authors: Haukenes Inger , Riise Trond , Haug Kjell , Farbu Erlend , Maeland John Gunnar
Published: May 2013

Background

Studies indicate that cigarette smokers have an increased risk for disability pension, presumably mediated by adverse health effects. However, smoking is also related to socioeconomic status. The current study examined the association between smoking and subsequent disability pension, and whether the association is explained by social confounding and/or health-related mediation.

Methods

A subsample of 7934 men and 8488 women, aged 40–46, from the Hordaland Health Study, Norway (1997–1999), provided baseline information on smoking status, self-reported health measures and socioeconomic status. Outcome was register-based disability pension from 12 months after baseline to end of 2004. Gender stratified Cox regression analyses were used adjusted for socioeconomic status, physical activity, self-reported health and musculoskeletal pain sites.

Results

A total of 155 (2%) men and 333 (3.9%) women were granted disability pension during follow-up. The unadjusted disability risk associated with heavy smoking versus non-smoking was 1.88 (95% CI 1.23 to 2.89) among men and 3.06 (95% CI 2.23 to 4.20) among women. In multivariate analyses, adjusting for socioeconomic status, HRs were 1.33 (95% CI 0.84 to 2.11) among men and 2.22 (95% CI 1.58 to 3.13) among women. Final adjustment for physical activity, self-reported health and musculoskeletal pain further reduced the effect of heavy smoking in women (HR=1.53, 95% CI 1.09 to 2.16).

Conclusions

Socioeconomic status confounded the smoking-related risk for disability pension; for female heavy smokers, however, a significant increased risk persisted after adjustment. Women may be particularly vulnerable to heavy smoking and to its sociomedical consequences, such as disability pension.
The impact of in-work tax credit for families on self-rated health in adults: a cohort study of 6900 New Zealanders
Authors: Pega Frank , Carter Kristie , Kawachi Ichiro , Davis Peter , Gunasekara Fiona Imlach , Lundberg Olle , Blakely Tony
Published: May 2013

Background

In-work tax credit (IWTC) for families, a welfare-to-work policy intervention, may impact health status by improving income and employment. Most studies estimate that IWTCs in the USA and the UK have no effect on self-rated health (SRH) and several other health outcomes, but these estimates may be biased by confounding. The current study estimates the impact of one such IWTC intervention (called In-Work Tax Credit) on SRH in adults in New Zealand, controlling more fully for confounding.

Methods

We used data from seven waves (2002–2009) of the Survey of Family, Income and Employment, restricted to a balanced panel of adults in families. The exposures, eligibility for IWTC and the amount of IWTC a family was eligible for, were derived for each wave by applying government eligibility and entitlement criteria. The outcome, SRH, was collected annually. We used fixed effects regression analyses to eliminate time-invariant confounding and adjusted for measured time-varying confounders.

Results

Becomingeligiblefor IWTC was associated with no detectable change in SRH over the past year (β=0.001, 95% CI −0.022 to 0.023). A $1000 increase in the IWTCamounta family was eligible for increased SRH by 0.003 units (95% CI −0.005 to 0.011).

Conclusions

This study found that becoming eligible for IWTC or a substantial increase in the IWTC amount was not associated with any detectable difference in SRH over the short term. Future research should investigate the impact of IWTC on health over the longer term.
Socioeconomic disadvantage and developmental delay among US children aged 18 months to 5 years
Authors: Simon Alan E , Pastor Patricia N , Avila Rosa M , Blumberg Stephen J
Published: May 2013

Background

Few studies have examined the relationship between sociodemographic factors and a population-based measure of developmental delay in US children. We identify sociodemographic factors associated with unlikely, probable and possible developmental delay in preschool US children using nationally representative data.

Methods

All children aged 18 months to 5 years in the 2007 National Survey of Children's Health were categorised into three groups based on the likelihood of developmental delay (unlikely delay, possible delay and probable delay) using a modified survey version of the Parents’ Evaluation of Developmental Status questionnaire. Bivariate and multivariate multinomial logistic regressions were used to assess relations between sociodemographic variables and risk of developmental delay.

Results

Children had increased odds of probable delay (compared with unlikely delay) if they were older (adjusted OR (aOR)=1.41/additional year above the youngest age group (18 months–2 years), p<0.001), male (aOR=1.55, p<0.001), low birth weight (aOR=2.08, p<0.001), non-Hispanic black (aOR=1.50, p<0.01) or Hispanic in a non-English-speaking household (aOR=2.53, p<0.001) versus non-Hispanic white, had lower household income (aOR=1.33 for each decreasing category of poverty level, p<0.001), or received >10 h/week of care at another family's home (aOR=1.71, p<0.05). Only four characteristics (being older, male, low birth weight and Hispanic living in a non-English-speaking household) were associated with increased odds of possible delay compared with unlikely delay.

Conclusions

Multiple factors, including demographic characteristics and indicators of social disadvantage, distinguish children with probable developmental delay from those unlikely to have developmental delay. Fewer factors identify children with possible delay.
Flow diversion versus traditional aneurysm embolization strategies: analysis of fluoroscopy and procedure times
Authors: Chalouhi Nohra , McMahon Jeffrey F , Moukarzel Lea A , Starke Robert M , Jabbour Pascal , Dumont Aaron S , Tjoumakaris Stavropoula , Gingold Eric L , Rosenwasser Robert , Gonzalez L Fernando
Published: May 2013

Background and objective

Flow diverters are increasingly used for treatment of complex intracranial aneurysms. The purpose of this study was to compare the pipeline embolization device (PED) and traditional embolization strategies in terms of fluoroscopy and procedure time.

Material and methods

Fluoroscopy and procedure times (in minutes) were retrospectively analyzed and compared between 127 patients treated with the PED, 86 patients treated with single stage stent assisted coiling (SAC), and 16 patients treated with Onyx HD 500 at our institution. A multivariate logistic regression analysis was performed to determine independent predictors of fluoroscopy and procedure time.

Results

The three groups were comparable with respect to patient age, gender, and ruptured/unruptured aneurysm status. Aneurysms treated with the PED were significantly larger than stent coiled aneurysms, and aneurysm location distribution differed significantly between the three groups. Mean fluoroscopy time was significantly increased in the SAC (55±31 min, p<0.001) and Onyx HD 500 (91±36 min, p<0.001) groups relative to the PED group (34±23 min). Likewise, mean procedure time was significantly longer in SAC (155±50 min, p<0.001) and Onyx HD 500 (176±65 min, p<0.001) patients compared with PED patients (131±36 min). In multivariate analysis, SAC/Onyx HD 500 versus PED independently predicted longer procedure and fluoroscopy times.

Conclusions

PED treatment requires significantly shorter fluoroscopy and procedure times compared with SAC and Onyx HD 500. The results of this study may be used by advocates of flow diverters as an additional argument for using this treatment modality to treat intracranial aneurysms.
Determination of ovulation time in sows based on skin temperature and genital electrical resistance changes
Authors: Luño V. , Gil L. , Jerez R. A. , Malo C. , González N. , Grandía J. , de Blas I.
Published: May 2013

Different physical and physiological parameters may be used to determine ovulation time in sows. In the present study, we analysed the ear and vulvar skin temperature fluctuations, and the changes in genital electrical resistance, at a distance of 4, 8 and 12 cm from the vulva during oestrus in order to predict the time of ovulation. Multiparous sows were checked by transrectal real‐time ultrasonography and luteinising hormone (LH) plasma concentration was determined. Temperature was measured using a thermoprecision infrared thermometer, and the electrical resistance was measured with a commercial resistance probe. All measurements were carried out every 12 hours from one day after the weaning to three days after oestrus onset. Skin temperature showed significant difference around periovulatory period. The electrical resistance at 4 cm from the vulva showed marked changes during oestrus, which were different from those described at 8 and 12 cm from the vulva. At 12 hours before ovulation time, skin temperature decreased significantly, and negative correlation (P<0.05) was found between vulvar skin temperature and vaginal resistance. There was no relationship between skin temperature, electrical resistance and LH plasma concentration. The measurement of several physiological traits may provide more accurate predictions of the moment of ovulation.
Analytical study on seismic force modification factors for cross-laminated timber buildings
Authors: Pei Shiling , Popovski Marjan , van de Lindt John W.
Published: May 2013

With two producers in operation and over 20 buildings already constructed or in planning process, use of cross-laminated timber (CLT) is gaining popularity in Canada. Since CLT as a structural system is currently not included in the National Building Code of Canada (NBCC), one of the most important issues are the values for the force modification factors for seismic design of CLT structures when NBCC equivalent static force procedure is used. In this study, a test-calibrated numerical model for CLT shear walls was applied to develop the design resistances for typical CLT wall configurations. An estimation of a possible range of Rd-factors was obtained by developing design variations for three multi-storey CLT apartment buildings. By specifying the desired seismic performance in terms of inter-storey drift, it is concluded that an Rd-factor of 2.0 will likely provide desirable building performance during the design earthquake level event in Vancouver, B.C.
THE CONTINUOUS SPECTRUM IN DISCRETE SERIES BRANCHING LAWS
Authors: HARRIS BENJAMIN , HE HONGYU , ÓLAFSSON GESTUR
Published: May 2013

If G is a reductive Lie group of Harish-Chandra class, H is a symmetric subgroup, and π is a discrete series representation of G, the authors give a condition on the pair (G, H) which guarantees that the direct integral decomposition of π|H contains each irreducible representation of H with finite multiplicity. In addition, if G is a reductive Lie group of Harish-Chandra class, and H ⊂ G is a closed, reductive subgroup of Harish-Chandra class, the authors show that the multiplicity function in the direct integral decomposition of π|H is constant along "continuous parameters". In obtaining these results, the authors develop a new technique for studying multiplicities in the restriction π|H via convolution with Harish-Chandra characters. This technique has the advantage of being useful for studying the continuous spectrum as well as the discrete spectrum.
Celastrol Induced DNA Damage, Cell Cycle Arrest, and Apoptosis in Human Rheumatoid Fibroblast-Like Synovial Cells
Authors: Xu Zengtao , Wu Guosheng , Wei Xu , Chen Xiuping , Wang Yitao , Chen Lidian
Published: May 2013

Celastrol is one of the principal active ingredients of Tripterygium wilfordii Hook.f., a toxic Chinese medical herb traditionally prescribed for controlling pain and inhibiting inflammation in various chronic inflammatory diseases, including rheumatoid arthritis (RA). Resistance to apoptosis of fibroblast-like synoviocytes is considered a major characteristic of RA. In this study, we test celastrol's cytotoxic effect and potential mechanisms in human rheumatoid synovial fibroblasts (RA-FLS). In the cytotoxic assay, we found that celastrol dose-dependently decreased RA-FLS viability and increased LDH release. The apoptotic nuclear morphology was observed after celastrol treatment as determined by DAPI fluorescence staining. Flow cytometry analysis with PI and Annexin V revealed that celastrol induced RA-FLS cell cycle arrest in the G2/M phase and apoptosis. Furthermore, celastrol dramatically increased expression of Bax/Bcl-2, proteolytic cleavage of Caspase-3, -9, PARP, and decreased expression of FasR. In addition, celastrol treatment resulted in DNA damage. Collectively, we concluded that celastrol inhibits RA-FLS proliferation by inducing DNA damage, cell cycle arrest, and apoptosis in vitro, which might provide data for its application in RA treatment.
PI3K/AKT/mTOR Signaling is Involved in (-)-Epigallocatechin-3-Gallate-Induced Apoptosis of Human Pancreatic Carcinoma Cells
Authors: Liu Shi , Wang Xiao-Jie , Liu Ying , Cui Yun-Fu
Published: May 2013

PI3K/AKT/mTOR signaling promotes cell survival, proliferation and progression in cancer cells. Targeting this pathway may lead to the development of novel therapeutic approaches for human cancers. Here, we examined the effects of (-)-epigallocatechin-3-gallate (EGCG) on the PI3K/AKT/mTOR pathway in pancreatic cancer cells, and assessed its therapeutic potential. In this study, the proliferation and apoptosis of PANC-1 cells were examined by MTT assay and flow cytometry, respectively. The expression of genes and proteins involved in the PI3K/AKT/mTOR pathway were measured by RT-PCR and western blotting, respectively. Our results revealed that EGCG dramatically inhibited the proliferation of PANC-1 cells and induced apoptosis simultaneously. Furthermore, it upregulated PTEN mRNA and protein expression levels, as well as downregulating the expression of phospho-AKT and phospho-mTOR. In conclusion, these results suggest that EGCG can suppress proliferation and induce apoptosis of PANC-1 cells in a time- and dose-dependent manner; moreover, EGCG also can upregulate PTEN expression and downregulate the expression of pAKT and p-mTOR to modulate the PI3K/AKT/mTOR signaling pathway.
MICRO-PATTERN GASEOUS DETECTOR TECHNOLOGIES AND RD51 COLLABORATION
Authors: TITOV MAXIM , ROPELEWSKI LESZEK
Published: May 2013

Discoveries in particle physics vitally depend on parallel advances in radiation-detector technologies. A true innovation in detector instrumentation concepts came in 1968, with the development of a fully parallel readout for a large array of sensing elements — the Multi-Wire Proportional Chamber (MWPC), which earned Georges Charpak a Nobel Prize in Physics in 1992. This invention revolutionized particle detection which moved from optical-readout devices (cloud chamber, emulsion or bubble chambers) to the electronics era. Over the past two decades advances in photo-lithography, microelectronics and printed-circuit board (PCB) techniques triggered a major transition in the field of gas detectors from wire structures to the Micro-Pattern Gas Detector (MPGD) concepts. The excellent spatial and time resolution, high rate capability, low mass, large active areas, and radiation hardness make them an invaluable tool to confront future detector challenges at the frontiers of research. The design of the new micro-pattern devices appears suitable for industrial production. Novel devices where MPGDs are directly coupled to the CMOS pixel readout serve as an "electronic bubble chamber" allowing to record space points and tracks in 3D. In 2008, the RD51 collaboration at CERN has been established to further advance technological developments of MPGDs and associated electronic-readout systems, for applications in basic and applied research. This review provides an overview of the state-of-the-art of the MPGD technologies and summarizes ongoing activities within the framework of the RD51 collaboration.
EVOLUTION OF ALGEBRAIC TERMS 1: TERM TO TERM OPERATION CONTINUITY
Authors: CLARK DAVID M.
Published: May 2013

This study was inspired by recent successful applications of evolutionary computation to the problem of finding terms to represent arbitrarily given operations on a primal groupoid. Evolution requires that small changes in a term result in small changes in the associated term operation. We prove a theorem giving two readily testable conditions under which a groupoid must have this continuity property, and offer evidence that most primal groupoids satisfy these conditions.
STICK AND RAMSEY NUMBERS OF TORUS LINKS
Authors: JOHNSON MARIBETH , MILLS STACY NICOLE , TRAPP ROLLAND
Published: May 2013

An algorithm that produces polygonal cable links is described, and applications discussed. In particular, the stick numbers of Tp,q torus links are shown to be 4p for 2p < q ≤ 3p, and it is shown that, in general, [Formula: see text]. Further, it is shown that the Ramsey number of a link is at least the sum of its arc index and bridge number. Using these results, we relate the Ramsey, stick and crossing numbers of torus links, showing [Formula: see text].
WEIGHTS OF MARKOV TRACES OF ALEXANDER POLYNOMIALS FOR MIXED LINKS
Authors: YAMANAKA HITOSHI
Published: May 2013

Using the Fourier expansion of Markov traces for Ariki–Koike algebras over ℚ(q, u1, …, ue), we give a direct definition of the Alexander polynomials for mixed links. We observe that under the corresponding specialization of a Markov parameter, the Fourier coefficients of Markov traces take quite a simple form. As a consequence, we show that the Alexander polynomial of a mixed link is essentially equal to the Alexander polynomial of the link obtained by resolving the twisted parts.
RIGIDLY ACHIRAL HYPERBOLIC SPATIAL GRAPHS IN 3-MANIFOLDS
Authors: IKEDA TORU
Published: May 2013

This paper provides a method for realizing an involution on an abstract graph, which does not restrict to an orientation-preserving automorphism on any cycle, by a rigidly achiral hyperbolic spatial embedding into the double of a compact connected orientable 3-manifold with non-empty aspherical boundary. As an application, we show that these hyperbolic spatial graphs are divided into two infinite families consisting of those which are homologically peripheral and those which are not.
HOMOGENEITY TESTS FOR MICHAELIS–MENTEN CURVES WITH APPLICATION TO FLUORESCENCE RESONANCE ENERGY TRANSFER DATA
Authors: BAÍLLO AMPARO , MARTÍNEZ-MUÑOZ LAURA , MELLADO MARIO
Published: May 2013

Resonance energy transfer methods are widely used for evaluating protein–protein interactions and protein conformational changes. Sensitized emission fluorescence resonance energy transfer (FRET) measures energy transfer as a function of the acceptor-to-donor ratio, generating FRET saturation curves. To reduce sampling variability effects, several replications (statistical samples) of the saturation curve are generated in the same biological conditions. Here we study procedures to determine whether these statistical samples are homogeneous, in the sense that they are extracted from the same underlying regression model (Michaelis–Menten kinetics). We used three methods to test the homogeneity of the samples: two hypothesis testing procedures (an F-test and bootstrap resampling) and model selection. The performance of the three methods was compared in a Monte Carlo study and through analysis in living cells of FRET saturation curves for dimeric CXCR4 complexes. This analysis shows that the F-test, the bootstrap procedure and the model selection method lead in general to similar conclusions, although the latter gave the best results when sample sizes were small, whereas the F-test and the bootstrap method were more appropriate for large samples. In practice, all three methods are easy to use simultaneously and show consistency.
EFFECT OF DEPOSITION CONDITIONS ON THE MICROSTRUCTURE AND THE THERMOELECTRIC PROPERTIES OF GALVANOSTATICALLY ELECTRODEPOSITED Bi2Te3 FILM
Authors: RASHID MOHAMMAD MAMUNUR , CHUNG GWIY-SANG
Published: May 2013

Bismuth Telluride ( Bi2Te3 ) films were deposited by a simple and cost-effective galvanostatic electrodeposition process from a solution containing bismuth tri-nitrate penta-hydrate and tellurium dioxide of different concentration ratios in 1 M nitric acid onto gold sputtered silicon substrate at various current densities. The effect of distinct current densities, electrolyte concentrations and electrodes distances on the microstructure and the thermoelectric properties of Bi2Te3 films were investigated. X-Ray diffraction (XRD) and field emission scanning electron microscope (FESEM) analysis ensured a high density, homogenous and near stoichiometric film. The surface morphology, crystalline structure and grain size were correlated with the applied current density. A prominent orientation (110) was observed for all the films and the grain size was acquired from 21 to 45 nm. The Seebeck measurement affirmed n-type semiconductor behavior of the deposited films. Enhancement in carrier mobility without significant change of the carrier concentration and Seebeck coefficient was achieved by tuning the electrodes distance. The thermoelectric film has a maximum measured Seebeck coefficient of –61.215 μV/K and a very high electrical conductivity of 2.13 × 103 Ω-1 ⋅ cm n-1. The maximum calculated power factor was 8.2 μ W ⋅ K -2 ⋅ cm -1.
FORMATION OF UNUSUAL COPPER CLUSTERS IN HELIUM NANODROPLETS
Authors: GOMEZ LUIS F. , LOGINOV EVGENY , HALDER AVIK , KRESIN VITALY V. , VILESOV ANDREY F.
Published: May 2013

Photoabsorption profiles of copper clusters, Cu N, grown in superfluid helium droplets were studied by beam depletion spectroscopy. For N below ~ 103 the spectra are characteristic of individual metallic particles, but in larger clusters a strong, broad absorption feature appears in the near-infrared region. This suggests a transition from single- to multicenter condensation: as the arrival frequency of metal atoms exceeds their transport time within the helium matrix, they nucleate into small individual agglomerates which later collect into a noncompact, possibly fractal or percolative assembly. The data, in concert with earlier observations on silver cluster growth, affirm that the formation of cluster–cluster aggregates with unusual optical properties is a general phenomenon achievable with the use of the helium nanodroplet technique.
AB INITIO STUDY OF DIFFERENT PROBABLE STRUCTURES OF GROUP III ANTIMONIDES
Authors: PANDEY ANOOP , DWIVEDI APOORVA , MUKHOPADHYAY SAIKAT , MISRA NEERAJ
Published: May 2013

Ab initio studies of the small ( AlSb , InSb , GaSb ) clusters is performed to investigate the changes in structural, vibrational and electronic properties. The calculated results clearly demonstrate that any change in the electronic configuration of the neutral clusters gives rise to noticeable changes in the structure. The structures of the neutral, positively and negatively charged clusters are fully optimized, taking the importance of the symmetry into account in all the cases. The changes in vibrational properties are explained keeping in mind the change in the interatomic distances due to any change in the electronic configuration.
REPRESENTATION NUMBERS OF TWO OCTONARY QUADRATIC FORMS
Authors: KÖKLÜCE BÜLENT
Published: May 2013

Let N(a1, …, a4; n) denote the number of representations of an integer n by the form [Formula: see text]. In this paper we derive formulae for N(1, 1, 1, 2; n) and N(1, 2, 2, 2; n). These formulae are given in terms of σ3(n).
A SEMI-ADELIC KUZNETSOV FORMULA OVER NUMBER FIELDS
Authors: MAGA PÉTER
Published: May 2013

In this paper, we prove a semi-adelic version of the Kuznetsov formula over number fields. This formula matches a weighted sum made of Fourier coefficients of cusp forms and Eisenstein series with a weighted sum of Kloosterman sums, the latter weight function is a kind of Bessel transform of the former one. We obtain a variant which is valid over all number fields. The admissible weight functions are important in applications, they depend on the archimedean parameters of the representations and show exponential decay. The automorphic vectors are not necessarily spherical in the archimedean aspect. Such formulas are proven to be useful in analytic number theory, e.g., in the estimate of L-functions on the critical line.
ON THE POLYNOMIAL xd + ax + b OVER 𝔽q AND GAUSSIAN HYPERGEOMETRIC SERIES
Authors: BARMAN RUPAM , KALITA GAUTAM
Published: May 2013

For d ≥ 2, denote by Pd(x) the polynomial over 𝔽q given by [Formula: see text]. We explicitly find the number of solutions in 𝔽q of the polynomial equation Pd(x) = 0 in terms of special values of dFd-1 and d-1Fd-2 Gaussian hypergeometric series with characters of orders d and d - 1 as parameters. This solves a problem posed by K. Ono (see p. 204 in [Web of Modularity : Arithmetic of the Coefficients of Modular Forms and q-Series, CBMS Regional Conference Series in Mathematics, No. 102 (American Mathematical Society, Providence, RI, 2004)]) on special values of n+1Fn Gaussian hypergeometric series for n > 2.
EICHLER COHOMOLOGY THEOREM FOR VECTOR-VALUED MODULAR FORMS
Authors: GIMENEZ JOSE
Published: May 2013

We prove the Eichler cohomology theorem for vector-valued modular forms of large integer weights on the full modular group.
THE RESTRICTED 3-COLORED PARTITION FUNCTION MOD 3
Authors: LIN BERNARD L. S.
Published: May 2013

In this paper, we investigate the divisibility of the function b(n), counting the number of certain restricted 3-colored partitions of n. We obtain one Ramanujan type identity, which implies that b(3n + 2) ≡ 0 ( mod 3). Furthermore, we study the generating function for b(3n + 1) by modular forms. Finally, we find two cranks as combinatorial interpretations of the fact that b(3n + 2) is divisible by 3 for any n.
CANONICAL HEIGHT FUNCTIONS FOR MONOMIAL MAPS
Authors: LIN JAN-LI , WANG CHI-HAO
Published: May 2013

The height function measures the arithmetic complexity of a point on a variety over [Formula: see text]. The canonical height function measures the asymptotic height growth (relative to the degree growth) of a point under a dominant rational map. One property desired for the canonical height function is the Northcott finiteness property, which states that there are only finitely many points for a bounded degree and a bounded height. We show that the canonical height function for dominant rational maps does not have the Northcott finiteness property in general. We develop a new canonical height function for monomial maps. In certain cases, this new canonical height function has the desired nice properties.
SILICON NANOPARTICLES/PEDOT–PSS NANOCOMPOSITE AS AN EFFICIENT COUNTER ELECTRODE FOR DYE-SENSITIZED SOLAR CELLS
Authors: SONG DANDAN , LI MEICHENG , BAI FAN , LI YINGFENG , JIANG YONGJIAN , JIANG BING
Published: May 2013

A novel inorganic/organic nanocomposite film composed of Si nanoparticles (NPs) and poly-(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT–PSS) is obtained from a simple mechanical mixture of Si NPs powder and aqueous PEDOT–PSS solution. Employing this composite film as a counter electrode, dye-sensitized solar cell (DSSC) exhibits an efficiency of 5.7% and a fill factor of 0.51, which are much higher than these of DSSC using pristine PEDOT–PSS electrode (2.9% and 0.25, respectively). The improvements in the photovoltaic performance of the former are primarily derived from improved electrocatalytic performance of the electrode, as evidenced by electrochemical measurements, the composite electrode has lower impedance and higher electrocatalytic activity when in comparison with pristine PEDOT–PSS electrode. These improvements are primarily deriving from the increased electrochemical surface by the addition of Si NPs. The characteristics of Si NPs/PEDOT–PSS composite counter electrode reveal its potential for the use of low-cost and stable Pt-free counter electrode materials. In addition, the results achieved in this work also provide a facile and efficient approach to improve the photovoltaic performance of DSSCs using PEDOT–PSS electrodes.
REVIEW OF CONVENTIONAL AIR CONDITIONING SYSTEM FOR INTERNAL COMBUSTION ENGINES
Authors: SEO JAE-HYEONG , KIM HYUNG-JIN , JUNG KWANG-JONG , KIM DAE-WAN , YEOM JEONG-KUK , LEE MOO-YEON
Published: May 2013

In spite of the increase of the concern on electric vehicles (which is called green cars) and electrically driven automotive air conditioning system, the conventional automotive air conditioning system for internal combustion engines has been still investigated widely due to the realistic consideration. This paper is intended to include many automotive air conditioning system articles published in 1997 to 2013. This review, although extensive cannot include every paper; some selection is necessary. Reviewed papers herein are related to the research and development on effective design and performance improvement for the automotive air conditioning system and components, including theoretical, numerical, analytical and experimental works. Therefore, a number of published articles about the automotive air conditioning system, which contain the belt-driven compressors, heat exchangers and refrigerants, were considered. Many researches have focused on improving the efficiency of automotive air conditioning system to decrease the usage rate of the internal combustion engines.
CORRELATION BETWEEN CHROMOPHORE IMPURITY CONTENT AND FIRED COLOUR DATA OF KAOLIN CLAY
Authors: AGRAWAL PARVESH , MISRA S. N. , SHARMA T.
Published: May 2013

Different kaolin clay specimen exhibit varying colours after firing depending upon the relative presence of different mineral impurities, physical state of mineral constituents etc. Spectrophotometers used for determining colour values generate many sets of colour data. Interpretation of such colour values is a subjective matter. Increase in darkness, yellowness etc as a consequence of increase in chromophore impurity content in kaolin clay have been shown. However, the inverse of above ie; gradual change in colour values along with gradual change in chromophore impurity content over a realistic range has not been studied. Whether the colour data of kaolin clay after firing can be taken up as a function of impurity content needs to be investigated. Thus, to identify the correlation between kaolin clay impurity content and it's fired colour data the present investigation examined the hypotheses i) The colour development after firing of kaolin clay is an indicator of chromophore impurity content present therein and ii) All the colour variables (L, a, b, ISO2470, redness) constituting a colour data set of pressed kaolin clay specimen after firing will vary in similar manner such that to represent variation in impurity content. The study indicated that the colour values obtained by spectrophotometry of clay specimens after firing represent the chromophore impurity present therein in a less reliable manner. To relatively estimate the quantity of chromophore impurity present in a clay sample from its fired colour, the sample should be mixed with 50% by weight of potash feldspar, pressed in to tablet suitable for colour measurement and fired at or above 1220°C to vitrify. After that the ‘L’, ‘a’ and ‘ISO2470’ values obtained truly represent the chromophore present therein.
USE OF CERAMIC MATERIAL (CEMENT CLINKER) FOR THE PRODUCTION OF BIODIESEL
Authors: SONI SUNNY , AGARWAL MADHU
Published: May 2013

Biodiesel is a renewable liquid fuel made from natural, renewable biological sources such as edible and non edible oils. Over the last years, biodiesel has gained more market due to its benefits and because it appears as the natural substitute for diesel. Reasons for growing interest in biodiesel include its potential for reducing noxious emissions, potential contributions to rural economic development, as an additional demand center for agricultural commodities, and as a way to reduce reliance on foreign oil. Biodiesel was prepared from soybean oil by transesterification with methanol in the presence of cement clinker. Cement clinker was examined as a catalyst for a conversion of soybean oil to fatty acid methyl esters (FAMEs). It can be a promising heterogeneous catalyst for the production of biodiesel fuels from soybean oil because of high activity in the conversion and no leaching in the transesterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, and reaction time, was carried out. The catalyst cement clinker composition was characterized by XRF. The results demonstrate that the cement clinker shows high catalytic performance & it was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 65°C, with a 6:1 molar ratio of methanol to oil, 21 wt% KOH/cement clinker as catalyst.
POSSIBLE USE OF FLY ASH IN CERAMIC INDUSTRIES: AN INNOVATIVE METHOD TO REDUCE ENVIRONMENTAL POLLUTION
Authors: SHARMA GAYATRI , MEHLA S. K. , BHATNAGAR TARUN , BAJAJ ANNU
Published: May 2013

The process of coal combustion results in coal ash, 80% of which is very fine in nature & is thus known as fly ash. Presently, in India, about 120 coal based thermal power plants are producing about 90-120 million tons of fly ash every year. With increase in demand of power energy, more and more thermal power plants are expected to commission in near future and it is expected that fly ash generation will be 225 million tons by 2017. Disposal of fly ash requires large quantity of land, water and energy and its fine particles, if not disposed properly, by virtue of their weightless, can become air born and adversely affect the entire Environment. These earth elements primarily consist of silica, alumina & iron etc. and its physicochemical parameters are closely resembles with volcanic ash, natural soil etc. These properties, therefore, makes it suitable for use in ceramic industries and helps in saving the environment and resources.
EFFECT OF Ni DOPING ON STRUCTURAL AND DIELECTRIC PROPERTIES OF GdFeO3
Authors: KAUR PAWANPREET , SHARMA K. K. , KUMAR RAVI , PANDIT RABIA
Published: May 2013

The polycrystalline samples of GdFe 1-x Ni x O 3(x=0.0, 0.1) are prepared by solid state reaction route, their structure is analyzed by powder X-ray diffraction (XRD) and Rietveld refinement. We are also studying the behavior of dielectric constant (ε′), tangent loss (tan δ) as a function of frequency from 75 kHz to 5 MHz and AC conductivity (σac) from 75 kHz to 1 MHz for both the compositions at room temperature. It is noticed that Ni 3+ ion substitution results in lattice contraction and enhancement in dielectric constant, tangent loss and AC conductivity.
MODELING OF PROCESS PARAMETERS AND ANALYSIS OF EFFECT OF VARIABLES IN THE DEAD BURNING OF MAGNESITE IN ROTARY KILN
Authors: CHAKRABARTI B. K.
Published: May 2013

The challenges of improving sintered MgO raw materials with special high temperature properties demand higher temperature calcination. In the process of dead burning of magnesite (DBM) in rotary kiln, the heat expenditures were found to be mainly due to dead burning of magnesite, loss through exhaust gases, loss through kiln shell by radiation & convection, clinker exit etc. The calcination process is highly energy intensive and involves various interdependent variable factors. An attempt was made to build a model and a screening design of experiment was performed with few process variables to identify the greatest effect of variables on the response quality. The design variables chosen were raw magnesite (RM) feed rate, kiln rotation (RPM), fuel consumption and burning zone temperature (BZT). The response variables were exit gas temperature and density of dead burnt magnesite (DBM). A fractional factorial design was used to keep the number of experimental runs to a minimum. ANOVA and normal plots were used to evaluate the effects of different variable factors on the sensory/response properties. The Experimental Design, ANNOVA, Response surface etc. given an insight of dead burning of magnesite in rotary kiln. This work had enabled us to correlate the BZT, RPM, RM feed with the exit gas temp and density of magnesite produced. The result opens up an avenue to look into the optimum region of operations within the ranges of variables considered in order to minimize the exhaust gas temp. and to maximize the density of the DBM produced.
OPTICAL PROPERTIES ON Li2O-K2O-WO3-B2O3 GLASS SYSTEM
Authors: EDUKONDALU A. , SAMEE M. A. , AHMMAD SHAIKH KAREEM , TAQIULLAH SAIR MD. , RAHMAN SYED , SIVA KUMAR K.
Published: May 2013

Mixed alkali tungsten borate glasses xLi2O–(30–x) K2O–10WO3–60B2O3 (0 < x < 30) were prepared from the melts. These glasses were characterized using X-ray diffraction, differential scanning calorimetry and density measurements. Optical absorption studies were carried out as a function of alkali content to look for mixed alkali effect (MAE) on the spectral properties of these glasses. From the study of ultraviolet absorption edge, the optical band gap energies and Urbach energies were evaluated. The average electronic polarizability of the oxide ion, optical basicity and the interaction parameters were also evaluated for all the glasses. Many of these parameters vary non-linearly exhibiting a minima or maxima with increasing alkali concentration, indicating the mixed alkali effect. An attempt is made to interpret MAE in this glass system in terms of its glass structure.
FIRST-PRINCIPLE STUDY OF STRUCTURAL AND ELECTRONIC PROPERTIES OF CUBIC STRONTIUM TITANATE
Authors: DAGA AVINASH , SHARMA SMITA , SHARMA K. S.
Published: May 2013

We have performed ab-initio investigation of SrTiO3 with cubic structure, and have computed its structural and electronic properties. The calculations are performed using a plane wave expansion within the local density approximation and the pseudopotential approximation. Results are given for the lattice constant, bulk modulus and charge density. The lattice parameter and bulk modulus calculated for SrTiO3within LDA are 3.908 Å and 184.6832 GPa respectively. It is found that the calculated lattice parameter and bulk modulus are in good agreement with the available experimental data. The charge density plots show higher accumulation of charge around the boundary and corners. All these calculations have been carried out using ABINIT computer code.
PULSED LASER DEPOSITION — ABLATION MECHANISM AND APPLICATIONS
Authors: RAO M. C.
Published: May 2013

Laser ablation is the process of removing material from a solid surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates. At high laser flux, the material is typically converted to a plasma. Usually, laser ablation refers to removing material with a pulsed laser, but it is possible to ablate material with a continuous wave laser beam if the laser intensity is high enough. In general, the method of pulsed laser deposition (PLD) is simple. Only few parameters need to be controlled during the process. Targets used in PLD are small compared with other targets used in other sputtering techniques. It is quite easy to produce multi-layer film composed of two or more materials. Besides, by controlling the number of pulses, a fine control of film thickness can be achieved. Pulsed-laser deposition has been used to deposit an extraordinarily wide range of materials. Historically, the most significant application of PLD has been in the area of high temperature superconducting thin films. The demonstration that PLD could be used to deposit YBa2Cu3O7-x (YBCO) films with zero resistivity at nearly 85 K sparked a significant amount of high temperature superconductivity research over the past decade and has stimulated research in PLD in general. The most striking limitations of PLD are the generation of particulates during the deposition process and the non uniform coating thickness, when substrates of large area are deposited.
ABRASIVE WEAR BEHAVIOUR OF COPPER-SiC AND COPPER-SiO2 COMPOSITES
Authors: UMALE TEJAS , SINGH AMARJIT , REDDY Y. , KHATITRKAR R. K. , SAPATE S. G.
Published: May 2013

The present paper reports abrasive wear behaviour of copper matrix composites reinforced with silicon carbide and silica particles. Copper – SiC (12%) and Copper-SiO2 (9%) composites were prepared by powder metallurgical technique. Metallography, image analysis and hardness studies were carried out on copper composites. The abrasive wear experiments were carried out using pin on disc apparatus. The effect of sliding distance and load was studied on Copper – SiC (12%) and Copper-SiO2 (9%) composites. The abrasive wear volume loss increased with sliding distance in both the composites although the magnitude of increase was different in each case. Copper – SiC (12%) composites exhibited relatively better abrasion resistance as compared to and Copper-SiO2 (9%) composites. The abraded surfaces were observed under scanning electron microscope to study the morphology of abraded surfaces and operating wear mechanism. The analysis of wear debris particles was also carried out to substantiate the findings of the investigation.
ELECTRICAL PROPERTY OF CONVENTIONALLY SINTERED ZnO
Authors: TAK S. K. , SHEKHWAT M. S. , MANGAL R.
Published: May 2013

ZnO powder was synthesized by solid state reaction method. The synthesized powder was granulated and pressed using uni-axial press for preparing the pallets. The prepared pellets were sintered in conventional furnace at different temperatures (900-1300° C). The phase study was done by powder X-ray diffraction and it was found that the there is no other phase present in the synthesized material but the peak intensity is increasing with temperature. The crystallite size of the synthesized ZnO powder was found to be increase with temperature. The effect of sintering on grain growth is investigated by scanning electron microscopy (SEM). SEM revels that the average grain size is increases with increase in sintering temperature. AC impedance of these samples was decreased markedly with increased sintering temperature. In present work the effect of sintering temperatures and hold time on micro structural and electrical properties of ZnO ceramics is carried out.
STRUCTURAL AND THERMODYNAMIC PROPERTIES OF MULTIFERROIC Y0.5Dy0.5MnO3
Authors: KUMAR SWAMY N. , GUPTA MANISH , DAS B. K. , PAVAN KUMAR N.
Published: May 2013

The structural and thermodynamic properties of polycrystalline samples of Y0.5Dy0.5MnO3 were investigated in order to investigate the effect of higher magnetic moment ion over Y ion. The structural transition from hexagonal to orthorhombic is observed at very high doping of Dy ion. Heat capacity measurements were performed at 2-300K in the application of different high magnetic field and the transition indicates the spin alignment of Mn 3+( TNMn3+ ). By using heat capacity data also calculated Debye temperature of the series.
MAGNETIC AND DIELECTRIC PROPERTIES OF POLYMER-CERAMIC COMPOSITES SYNTHESIZED USING A MELT COMPOUND TECHNIQUE
Authors: JOTANIA RAJSHREE , CHANMAL CHETAN , JOG JYOTI
Published: May 2013

Polymer composites have emerged as a new class of materials, which have attracted technologist as they display novel properties compared to traditional materials and dramatically improves the performance properties of polymer system. We have synthesized hexaferrite-polymer composites of Polyvinylidene Fluride (PVDF) with BaCa2Fe16O27 (2.0, 5.0 % wt/vol.) using a melt compounding technique. BaCa2Fe16O27 hexaferrite powder was prepared using a microemulsion technique and directly mixed in melted PVDF, following by a low temperature hot pressing. The composites of PVDF with various weight percent of BaCa2Fe16O27 (2.0 & 5.0% wt/vol.) were processed via melt mixing at 200°C, with 60 rpm for 5 minutes. The films of uniform thickness are about 0.5 mm is obtained by a compression molded instrument at 200°C under 5-ton pressure. The influence of BaCa2Fe16O27 hexaferrite contents on magnetic and dielectric properties of composite was investigated. The prepared PVDF- BaCa2Fe16O27 composite thick films were characterized for their magnetic; dielectric and thermal behavior employing magnetic, dielectric and thermal analysis (TGA/DTA). Maximum saturation magnetization was obtained for 5 % wt/vol. of barium calcium hexaferrite composite.
BRIGHT SOLITONS IN A PARAMETRICALLY DRIVEN DISCRETE NONLINEAR SCHRODINGER EQUATION
Authors: SWAMI O. P. , KUMAR V. , NAGAR A. K.
Published: May 2013

In this paper, we consider a parametrically driven discrete nonlinear Schrödinger equation. Analytical and numerical calculations are performed to determine the existence and stability of fundamental bright discrete solitons admitted by discrete nonlinear Schrödinger equation. We show that a parametric driving can destabilizes onsite bright solitons and stabilizes intersite bright discrete solitons. Stability windows of all the fundamental solitons are presented and approximations to the onset of instability are derived using perturbation theory, with accompanying numerical results.
A BRIEF SURVEY ON BASIC PROPERTIES OF THIN FILMS FOR DEVICE APPLICATION
Authors: RAO M. C. , SHEKHAWAT M. S.
Published: May 2013

Thin film materials are the key elements of continued technological advances made in the fields of optoelectronic, photonic and magnetic devices. Thin film studies have directly or indirectly advanced many new areas of research in solid state physics and chemistry which are based on phenomena uniquely characteristic of the thickness, geometry and structure of the film. The processing of materials into thin films allows easy integration into various types of devices. Thin films are extremely thermally stable and reasonably hard, but they are fragile. On the other hand organic materials have reasonable thermal stability and are tough, but are soft. Thin film mechanical properties can be measured by tensile testing of freestanding films and by the micro beam cantilever deflection technique, but the easiest way is by means of nanoindentation. Optical experiments provide a good way of examining the properties of semiconductors. Particularly measuring the absorption coefficient for various energies gives information about the band gaps of the material. Thin film materials have been used in semiconductor devices, wireless communications, telecommunications, integrated circuits, rectifiers, transistors, solar cells, light-emitting diodes, photoconductors and light crystal displays, lithography, micro- electromechanical systems (MEMS) and multifunctional emerging coatings, as well as other emerging cutting technologies.
STUDY OF SUBSTITUTION OF Zn FOR Cu IN YBa2Cu3O7 SYSTEM
Authors: SHARMA P. K. , SAMARIYA A. , DHAWAN M. S. , SINGHAL R. K.
Published: May 2013

The polycrystalline YBa2(Cu1-XZnX)3O7-δ samples (x=0.0 to 0.06) were synthesized and studied using X Ray diffraction, titration, resistivity, magnetization and X ray photoelectron spectroscopy (XPS). Results show that O2 stoichiometry (δ) changes on Zn substitution which affects their normal state resistivity as well as the TC. Zn also induces local magnetic moment as evidenced from magnetization results. A combination of change in O2 stoichiometry and magnetic pair breaking is found to be responsible for a rapid suppression of superconductivity.
BIOLOGICAL ACTIVITY PREDICTIONS AND HYDROGEN BONDING ANALYSIS IN QUINOLINES
Authors: GUPTA PALVI , KAMNI
Published: May 2013

The paper has been designed to make a comprehensive review of a particular series of organic molecular assembly in the form of compendium. An overview of general description of fifteen quinoline derivatives has been given. The biological activity spectra of quinoline derivatives have been correlated on structure activity relationships base which provides the different Pa (possibility of activity) and Pi (possibility of inactivity) values. Expositions of the role of intermolecular interactions in the identified derivatives have been discussed with the standard distance and angle cut-off criteria criteria as proposed by Desiraju and Steiner (1999) in an International monogram on crystallography. Distance-angle scatter plots for intermolecular interactions are presented for a better understanding of the packing interactions which exist in quinoline derivatives.