bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomechanical effect of abutment on stability of orthodontic mini‐implant
Authors: Motoyoshi Mitsuru , Yano Shinya , Tsuruoka Takashi , Shimizu Noriyoshi
Published: August 2005

Abstract: The biomechanical influences of primary factors on titanium mini‐implant, which is used as an anchorage for orthodontic tooth movement, were quantified using the three‐dimensional finite element method. Six types of finite element models were designed to show various thread pitches from 0.5 to 1.5 mm. Three models were designed with abutment and three other models without abutment. A traction force of 2 N was applied to the head of the mini‐implant or abutment to be at 45° to the bone surface. No remarkable differences were observed in the stress distribution patterns regardless of thread pitch variance. However, the stress distribution was remarkably different between models with abutment and without abutment. The maximum stress of the model with abutment and thread pitch 0.5 mm was the least as compared with the other models. Areas of high‐level stress were obviously smaller than in the models without abutment. The plots of the displacement distributions of the models with abutment also presented significant pattern differences as compared with the models without abutment. The high‐level area was localized to the head of the implant and the abutment in models with abutment. Therefore, the existence of the abutment is significantly useful in decreasing the stress concentration on the bone, while the effect of thread pitch was uncertain.
In vitro accuracy of a novel registration and targeting technique for image‐guided template production
Authors: Widmann Gerlig , Widmann Roland , Widmann Ekkehard , Jaschke Werner , Bale Reto Josef
Published: August 2005

Objectives: The objective of this study was to evaluate the accuracy of a novel registration and targeting technique for image‐guided template production (IGTP) in a preliminary phantom study.

Material and methods: Registration of four standard dental stone casts with integrated target pellets to the corresponding computed tomography (CT) data was performed via a vacuum mouthpiece and an external reference frame (Medical Intelligence GmbH, Germany). Using the Treon navigation system (Medtronic Inc., Minneapolis, MN, USA) a surgical path with the entry in the centre of the dental crown and the target in the centre of the target pellet was planned on the CT data. An aiming device was adjusted according to the planned trajectory and guided drillings into the dental stone casts. The accuracy was evaluated on postoperative 3D‐CT data.

Results: The mean fiducial registration error as given by the registration software was 0.4 mm. One hundred and twelve navigated drillings showed a mean accuracy [xy] of 0.42±0.26 mm (maximum 1 mm). For the z‐axis, a mean accuracy [z] of 0.25±0.12 mm (maximum 0.6 mm) was found.

Conclusions: Comparing the presented registration technique to existing registration methods in IGTP and burr tracking, no radiographic and registration templates are needed. The procedure is easy and requires only minimal effort. Navigation‐controlled drillings could be performed with an accuracy that approaches the intrinsic navigation system's accuracy, a fact that warrants its use for surgical template production. Further accuracy studies of template‐guided drillings are necessary before the presented registration technique can be implemented for patient treatment.
Control of Charge Dilution in Turbocharged Diesel Engines via Exhaust Valve Timing
Authors: Yilmaz Hakan , Stefanopoulou Anna
Published: August 2005

In this paper we extend an existing crank angle resolved dynamic nonlinear model of a six-cylinder 12 l turbocharged (TC) Diesel engine with exhaust valve closing (EVC) variability. Early EVC achieves a high level of internal exhaust gas recirculation (iEGR) or charge dilution in Diesel engines, and thus reduces generated oxides of nitrogen (NOx). This model is validated in steady-state conventional (fixed EVC) engine operating points. It is expected to capture the transient interactions between EVC actuation, the turbocharger dynamics, and the cylinder-to-cylinder breathing characteristics, although this has not been explicitly validated due to lack of hardware implementation. A nominal low order linear multi-input multi-output model is then identified using cycle-sampled or cycle-averaged data from the higher order nonlinear simulation model. Various low-order controllers that vary EVC to maximize the steady-state iEGR under air-to-fuel ratio (AFR) constraints during transient fueling demands are suggested based on different sensor sets. The difficulty in the control tuning arises from the fact that the EVC affects both the AFR and engine torque requiring coordination of fueling and EVC. Simulation results are shown on the full order model.
Francisella tularensisEnters Macrophages via a Novel Process Involving Pseudopod Loops
Authors: Clemens Daniel L. , Lee Bai-Yu , Horwitz Marcus A.
Published: August 2005

Intracellular bacterial pathogens employ a variety of strategies to invade their eukaryotic host cells. From an ultrastructural standpoint, the processes that bacteria employ to invade their host cells include conventional phagocytosis, coiling phagocytosis, and ruffling/triggered macropinocytosis. In this paper, we describe a novel process by whichFrancisella tularensis, the agent of tularemia, enters host macrophages.F. tularensisis a remarkably infectious facultative intracellular bacterial parasite—as few as 10 bacteria can cause life-threatening disease in humans. However, the ultrastructure of its uptake and the receptor mechanisms that mediate its uptake have not been reported previously. We have used fluorescence microscopy and electron microscopy to examine the adherence and uptake of a virulent recent clinical isolate ofF. tularensis, subspeciestularensis, and the live vaccine strain (LVS), subspeciesholarctica, by human macrophages. We show here that both strains ofF. tularensisenter human macrophages by a novel process of engulfment within asymmetric, spacious pseudopod loops, a process that differs ultrastructurally from all previously described uptake mechanisms. We demonstrate also that adherence and uptake ofF. tularensisby macrophages is strongly dependent upon complement receptors and upon serum with intact complement factor C3 and that uptake requires actin microfilaments. These findings have significant implications for understanding the intracellular biology and virulence of this extremely infectious pathogen.
The Population Biology of Mitochondrial DNA and Its Phylogenetic Implications
Authors: Ballard J. William O. , Rand David M.
Published: August 2005

▪ Abstract  The reconstruction of evolutionary trees from mitochondrial DNA (mtDNA) data is a common tool with which to infer the relationships of living organisms. The wide use of mtDNA stems from the ease of getting new sequence data for a set of orthologus genes and from the availability of many existing mtDNA sequences for a wide array of species. In this review we argue that developing a fuller understanding of the biology of mitochondria is essential for the rigorous application of mtDNA to inferences about the evolutionary history of species or populations. Though much progress has been made in understanding the parameters that shape the evolution of mitochondria and mtDNA, many questions still remain, and a better understanding of the role this organelle plays in regulating organismal fitness is becoming increasingly critical for accurate phylogeny reconstruction. In population biology, the limited information content of one nonrecombining genetic marker can compromise evolutionary inference, and the effects of nuclear genetic variation—and environmental factors—in mtDNA fitness differences can compound these problems. In systematics, the limited gene set, biased amino acid composition, and problems of compensatory substitutions can cloud phylogenetic signal. Dissecting the functional bases of these biases offers both challenges and opportunities in comparative biology.
Lipid Peroxides and Antioxidant Enzymes in Cisplatin‐Induced Chronic Nephrotoxicity in Rats
Authors: González Ricardo , Romay Cheyla , Borrego Aluet , Hernández Frank , Merino Nelson , Zamora Zullyt , Rojas Enis
Published: August 2005

Cisplatin (CDDP), an anticancer drug, induces remarkable toxicity in the kidneys of animals and humans and it has been well documented that reactive oxygen species and the renal antioxidant system are strongly involved in acute renal damage induced by CDDP. The aim of the present study was to investigate whether or not the renal antioxidant system plays also an important role in chronic renal damage induced by
repeated doses of CDDP (1 mg/kg intraperitoneally twice weekly during 10 weeks in rats). In order to elucidate it, serum creatinine and urea levels, renal glutathione and thiobarbituric
acid‐reactive substances (TBARS) content, as well as renal superoxide dismutase and glutathione peroxidase activities were measured in the kidney homogenates of chronically CDDP‐treated rats and additionally histological studies were performed in the rat kidneys. The chronic treatment with CDDP induced a significant increase in creatinine and urea levels in serum, but the other parameters mentioned above were not significantly modified as compared to the values in nontreated rats. Taking into account these results, we conclude that chronic CDDP administration induces also severe nephrotoxicity, in contrast to CDDP acute application, without any significant modification in the activity of relevant antioxidant enzymes such as superoxide dismutase and glutathione peroxidase, renal glutathione and lipid peroxides, by which the role of the antioxidant system in chronic nephrotoxicity induced by CDDP in rats is uncertain.
Serum Levels of the MCP‐1 Chemokine in Patients With Ischemic Stroke and Myocardial Infarction
Authors: Arakelyan A. , Petrkova J. , Hermanova Z. , Boyajyan A. , Lukl J. , Petrek M.
Published: August 2005

Chemokine‐driven migration of inflammatory cells has been implicated in pathogenesis of atherosclerosis‐associated conditions such as ischemic stroke and myocardial infarction. In this study, a candidate chemokine, monocyte chemoattractant protein (MCP)‐1, was investigated in patients with both aforementioned manifestations of atheroslerotic inflammation. MCP‐1 levels in serum were determined by ELISA in 40 healthy, control subjects (C), 40 patients with ischemic stroke (IS), and in 64 patients with myocardial infarction (MI). Statistical analysis utilised Mann‐Whitney test, Fisher′s exact test, and Spearman′s rank correlation (P < .05). In comparison to control subjects (C; median/interquartile range: 239/126 pg/mL), MCP‐1 serum levels were increased in both investigated patient cohorts
(IS: 384/370, P < .001; MI: 360/200, P < .002). There was a substantial variability of MCP‐1 serum levels, especially in the
IS group. No relationship was observed between chemokine levels and atherosclerosis risk factors (hypertension, diabetes, smoking, and alcohol consumption), and MCP‐1 was also not related to age or gender. Elevation of MCP‐1 in circulation of patients with atherosclerosis‐associated complications implicates this CC chemokine ligand (CCL)2 in inflammatory processes, which contribute to pathogenesis of myocardial infarction and ischemic stroke. Further investigations, including patient stratification, are however necessary to evaluate if MCP‐1 can be utilised for clinical management of patients with these diseases.
Markets and Famines in Pre-Industrial Europe
Authors: Gráda Cormac Ó
Published: August 2005

How markets perform during famines has long been a contentious issue. Recent research tends to associate famine with market segmentation and hoarding. Evidence based on an analysis of the spatial and temporal patterns of food-price movements during four famines in pre-industrial Europe indicates that markets functioned “normally” in times of crisis.
Propensity-Score Methods and the Lenin School
Authors: Cohen Gidon
Published: August 2005

Although social scientists often use propensity-score methods to study databases that contain substantial amounts of bias and missing information, these techniques have not been applied in the historical literature. This article uses propensity-score matching to investigate the impact of Moscow training on the selection of leadership cadres within Britain's Communist Party. These matching techniques can enable the quantitative analysis of a range of previously underutilized historical data.
Confrontation, Simulation, Admiration: The Wooster Group's Poor Theater
Authors: Dunkelberg Kermit
Published: August 2005

The Wooster Group's Poor Theater questions the state of contemporary performance by trying on the styles of a vanished group, the Polish Laboratory Theatre, dissolved in 1984; and a vanishing one, the Ballett Frankfurt, disbanded in August 2004 (half a year after Poor Theater had its first showing) and resurrected as the smaller Forsythe Company in 2005.
Violent Capital: Zhu Yu on File
Authors: Cheng Meiling
Published: August 2005

In the past two decades, China has witnessed a period of vibrant artistic experimentation, marking the nation's rapid transition from the dominance of communist ideology to that of the market economy. Zhu Yu's xingwei yishu (behavior art) and his controversial art actions reflect and critique this transition, and his performances become part of the “violent capital” of the new aesthetic economy.
From Virtual to Local Realities: Access to ICT and Women Advocacy Networks in Turkey
Authors: Törenli Nurcan
Published: August 2005

The purpose of this paper is to explore the advocacy networks in the local context of Turkey. To avoid the limitations stemming from the unfounded optimism of the mainstream theoretical approaches (Idealist model) undermining the level of socioeconomic development of Turkey, the paper employs the realistic/alternative approach called "knowledge society perspective." In the theoretical part (Section 2), I compare and contrast the two theoretical approaches and discuss the policy implications from a critical perspective. It is claimed that the knowledge society approach is more appropriate in the understanding of specific problems of Turkey with regard to the production, distribution, access, and power relationships in the context of ICTs. The main empirical focus of the paper is women advocacy networks and their use of ICTs. In order to substantiate the claims developed in the theoretical discussion, the results of the survey conducted among women advocacy networks are presented. The main finding of the survey shows that, in the context of Turkey, the ICTs and advocacy networks are used only by an elite sector of the Turkish women. In contrast with the assumed potential of the ICTs as inclusive technologies, the fact that they can work to exclude large segments of the population casts doubt on the universal validity claims of the mainstream theories.
The Human Rights Discourse in Health
Authors: Schuftan Claudio
Published: August 2005

As is long overdue, this paper attempts to expose "health development" professionals to the Human Rights discourse in the health sector. This paper is presented as an advocacy piece for an alternative to the existing "Health Sector Reform" (HSR). HSR is primarily advocated by the World Bank and is influencing World Health Organization (WHO) policy (WHO 2000). Literature concerning the contrasting of these two approaches to health is scarce. Consequently, for many readers, this paper will mark their first exposure to the human rights-based approach to work in health; for others, it will reinforce and refresh some of their already known key concepts.
Investment in Information and Communication Technologies (ICT) and its Payoff in Malaysia
Authors: Kuppusamy Mudiarasan , Santhapparaj A. Solucis
Published: August 2005

Information and communication technologies (ICT) have become the key drivers for socioeconomic development in recent years. This paper provides an empirical examination on the impact of ICT on Malaysian economic growth over the period 1975-2002 by using secondary data. Real GDP has been used as the dependent variable with three independent variables, namely, investment on ICT, non-ICT investment, and total labor employed in the economy. The unrestricted error correction method (UECM) and the cointegration bounds test revealed that the ICT had contributed positively to Malaysia's economic growth over the study period. The empirical result reflects the benefits gained from the immense ICT-based investment made in the country over the years. Further, several policy recommendations are discussed on how Malaysia can achieve better economic growth by leveraging of ICT.
"Just a Time-Pass": Acknowledgement/Denial (?) of Sexual Harassment in Young Women's Discourse
Authors: Zubair Shirin
Published: August 2005

Using the feminist techniques of unstructured interviews and self-participatory approach, I analyze the constructions of sexuality and sexual harassment in the discourses of women and men entering higher education, and the wider Pakistani society. The content, themes and discursive linguistic choices from the interview narratives of 16 young women who have experienced sexual harassment in educational institutions, workplace and streets have been analyzed. The data helps to illustrate that sexual harassment is a mechanism of social control, deeply linked to the patriarchy and power structures of Pakistani society. It is neither researched nor reported in public discourses hence it is perpetuated and reinforced by both men and women. The analysis shows that women's unawareness of certain forms of harassment, their silence and dismissal of it as "just a time-pass" (an idiom in Pakistani English which is equivalent to "just a pastime" in standard English) constructing it as a non-violent behavior obliquely reinforce it.
The Transitional Woman: A Case Study of Values in the Context of an Arabic/Islamic Society
Authors: Walters Timothy , Walters Lynne
Published: August 2005

The purpose of this paper is fourfold. It is first in a series of studies designed to examine: 1) Rokeach's Terminal and Instrumental Values typology in the context of non-Western culture, specifically Arab/Islam of the United Arab Emirates, 2) whether there are emerging (perhaps transitional) family and female typologies based on these value sets, 3) the relationship between outside forces (the economy and public policy for example) and the family, and 4) it is also meant to gather questions for future study.The paper is based on a survey of students at the all-female Zayed University in Dubai. The results suggested differences between groups of students with respect to Rokeach's Terminal and Instrumental Values. Environmental factors that seem to influence these differences included religion, education, urbanization, and the changing role of women in society.Findings suggest that Rokeach's values system must be rephrased, gathering terms bound to Arabic/Islamic Society to determine what terms are synonymous and what are not. Before the questions of whether a new value system is emerging in the modernizing Arab/Islamic world, where that value system is coming from, and how values are generated can be studied, the old value system must be known. Determining these benchmarks, then, is the next step in what could be a rich, rewarding stream of work adding to multi-cultural understanding.
Markov Chain Models of Communication Processes in Negotiation
Authors: Smith Philip , Weingart Laurie , Olekalns Mara
Published: August 2005

Markov chain analysis provides a way to investigate how the communication processes in dyadic negotiations are affected by features of the negotiating context and how, in turn, differences in communication processes among dyads affect the quality of the final settlement. In Markov models, the communication process is represented as a sequence of transitions between states, which describes how tactics are used and how they are reciprocated during the course of a negotiation. This article provides an introduction to Markov chain analysis and shows, using simulated data, how Markov chain models may be analyzed using widely-available loglinear modeling software. Model selection, assessment of the order of a chain, analysis of residuals, and sample size are discussed.
When, Where and How: The Use of Multidimensional Scaling Methods in the Study of Negotiation and Social Conflict
Authors: Gelfand Michele , Duan Lili , Pinkley Robin
Published: August 2005

MDS (multidimensional scaling) is a technique that enables researchers to uncover the spatial representation or "hidden structure" that underlies and defines behavioral data – such as negotiator or disputant perceptions and preferences. Although MDS has wide-ranging theoretical and applied appeal, it has been highly underutilized in the conflict and negotiation literature. In this paper, we seek to illustrate the promise that MDS offers in the study of conflict and negotiation. We begin with a discussion of how MDS can be differentiated from other multivariate techniques, such as factor analysis. Next we provide a brief overview of multidimensional scaling techniques – highlighting the various methods available for collecting proximity data and the computer analysis programs that can be used to analyze them. We further review the nature of the results and the ways in which they are interpreted. We conclude with some examples of the types of questions that have been addressed using MDS in the conflict and negotiation literature and a discussion about the promise this technique has for future research.
Disparate Methods and Common Findings in the Study of Negotiation
Authors: De Dreu Carsten , Carnevale Peter
Published: August 2005

In this article, we compare the relative popularity of a wide variety of methods and techniques used in the study of conflict and negotiation across five domains of inquiry: political science, communication sciences, social and personality psychology, economics, and organizational behavior. An analysis of articles on conflict and negotiation published between 1997 and 2001 suggests that laboratory experiments that entail coding of behavior and self-reported data using surveys are especially popular in psychology, organizational behavior, and communication sciences. Mathematical modeling, the use of experimental games, and the use of archival data are especially popular in economics and political science. Diverse methods can provide convergent insights, and this is observed clearly in work on gain-loss framing and on reciprocity in negotiation. We suggest that researchers adopt, or continue to employ, triangulation as an approach to validity: When two or more methods or data sources converge on a construct, we develop greater assurance that our conclusions are not driven by an error or artifact of any one procedure. Each method exhibits strengths and weaknesses, and to the extent they do not overlap but show common effects, we stand on more solid ground with our theoretical conclusions.
Methodologies for Studying Personality Processes in Interpersonal Conflict
Authors: Graziano William , Jensen-Campbell Lauri
Published: August 2005

The inevitability of conflict stems from three apparently-panhuman psychological tendencies: 1) People differ in their attitudes, beliefs, knowledge, and life experiences; 2) Such differences induce people to be egocentric, and often to have difficulty perceiving the perspectives of others; and 3) People are generally motivated to protect and promote their own self-interests. For this perspective, conflict is an emergent property of relationships that appears during interaction between two or more persons. Thus, understanding the influence of personality on social conflict must look past simple main effects models that focus on either situations or personality. This article discusses various research methods that can be used to assess personality's contribution to conflict behavior. It then focuses on statistical advances that recognize the complex nature of interactions between individual, their partners, and the situation when studying conflict.
The Method of Experimental Economics
Authors: Croson Rachel
Published: August 2005

There are many similarities between experimental economics and psychological research, both substantive and methodological, but there are important differences as well. This article discusses five methodological areas where experimental economists and experimental psychologists differ:incentives, context, subject pools, deception, experimental details and data analysis. Within each topic I present the economists' methodology and rationale and contrast it with current practice in psychology and management research. My hope is that this article will lead not only to a deeper understanding of each field's choice of methodology, but also to practical advice for researchers toward having their work read and accepted by their colleagues in related disciplines.
Comparative Case Studies
Authors: Zartman I. William
Published: August 2005

Case studies embody a deep knowledge of the subject and can be used to test or generate theoretical propositions for explaining negotiated outcomes. Their value is increased when they are employed comparatively, using a number of instances of negotiation – flawed or successful – in the same conflict or problem or a number of negotiations of different conflicts. While it might appear that statistical studies of large numbers of cases would be even more advantageous, these studies tend to lose the feel and understanding that comparative cases can command. Thus, comparative case studies lie at the crossroads of reality and theory; they present their evidence through the eyes of a knowledgeable specialist and they test it against the hypothetical constructs of a creative conceptualist. The challenge is as high as the payoffs.
All that Glitters is Not Gold: Examining the Perils and Obstacles in Collecting Data on the Internet
Authors: Siah Cha Yeow
Published: August 2005

The speed, ease and cost of conducting an internet-based study has attracted an increasingly large number of researchers to the medium for data collection. The lure of conducting research on the internet warrants heightened awareness of the practical problems one may encounter in the course of design and data collection. Researchers should also be attuned to the various threats of reliability and validity that may affect the quality of their data. This article surveys the past literature and identifies four main areas of concern in internet-based research: (1) sampling error and generalizability; (2) subject fraud; (3) measurement errors resulting from extraneous factors, and (4) the ethics of conducting research on the internet. Before carrying out their research on the internet, researchers should carefully weigh the sometimes hidden costs against the obvious benefits to consider whether the results obtained will be seriously compromised by the problems currently existing with this relatively new medium. However, a more productive approach recognizes that this research method is here to stay and thus greater attention needs to be given to refining and clearing the hurdles that internet-based researchers currently face.
Managing Conflict in the Literature: Meta-analysis as a Research Method
Authors: Stuhlmacher Alice , Gillespie Treena
Published: August 2005

No longer on the fringes of research design, meta-analysis has established a methodological foothold in social science research. The use of meta-analysis as a research method to study social conflict, however, remains limited. This article is designed to increase the accessibility of meta-analyses, while identifying issues and controversies. To this end, we offer examples from our own experiences in an overview of the development, choices, and challenges of a meta-analysis, as well as more technical references for further instruction.
Corrosion inhibition of pure nickel by some phosphonium compounds in acid medium
Authors: Walia Meetu , Singh Gurmeet
Published: August 2005

The inhibition of corrosion of nickel in H2SO4 solution in presence of some phosphonium inhibitors at different concentrations and temperatures is investigated. The inhibition efficiency increases with increasing inhibitor concentrations. Polarization studies indicate that the compounds used are all mixed inhibitors. The kinetics of corrosion is studied. Potentiodynamic polarization studies indicate that these compounds are good passivators in 1N H2SO4. Inhibition by these compounds due to adsorption on metal surface was also studied and supplemented with infrared spectroscopy and SEM studies. Certain quantum chemical parameters have been calculated to reinforce the electrochemical results.
Hard anodisation of aluminium and its application to sensorics
Authors: Rajendra A. , Parmar Biren J. , Sharma A. K. , Bhojraj H. , Nayak M. M. , Rajanna K.
Published: August 2005

Hard anodising is normally carried out with electrolytes at subzero temperatures and with a very high current density. This may sometimes lead to burning and powdered deposits. In this work, a method of hard anodising at a higher temperature (10°C) using a pulsed power supply is investigated. The quality of coating obtained with this process is better than that obtained with the conventional method. Furthermore, it minimises the refrigeration requirements for cooling the electrolyte and eliminates the problem of burning and powdery coatings. The application of hard anodic coating with insulation resistance 1–30 GΩ up to 100 V dc to a pressure sensor as an insulating base layer is explored. The pressure sensor diaphragm is hard anodised, and this is followed by the deposition of a thin platinum–tungsten (92Pt–8W) film as strain sensor. The fabrication, characterisation and calibration of the pressure sensor and its applications are discussed.
Black permanganate conversion coatings on aluminium alloys for thermal control of spacecraft
Authors: Uma Rani R. , Sharma A. K. , Mayanna S. M. , Bhojraj H. , Bhandari D. R.
Published: August 2005

A black conversion coating on aluminium alloys in an electrolyte system consisting of potassium permanganate, copper nitrate, arsenic trioxide and nitric acid was investigated. To optimise the process, the effects of various operating parameters, i.e. electrolyte concentration, operating temperature, treatment time and coating thickness, on the physico-optical properties of the coating were investigated. The chemical nature of the coating was evaluated with EDX and infrared spectral studies. The microstructure of the coating was investigated with SEM. The thermal nature of the coatings was evaluated by thermal studies. The space worthiness of the coating was evaluated by humidity, thermal cycling, thermovacuum performance tests and measurement of optical properties. The black coating provides higher emissivity as well as higher solar absorptance in the order ∼0·80.
Comparative study on the effect of current density on Ni and Ni–Al2O3 nanocomposite coatings produced by electrolytic deposition
Authors: Aruna S. T. , Diwakar S. , Jain A. , Rajam K. S.
Published: August 2005

Nickel was deposited galvanostatically at 0·23, 0·77, 1·55, 3·1 and 5·4 A dm−2 current densities at room temperature. An XRD technique was employed for evaluating the grain size and preferred orientation of the nickel deposit. The cross-sections of the nickel deposits were subjected to microhardness and microstructure analysis. Nanosize alumina was prepared by a solution combustion technique, and the powder was characterised by XRD and particle size analysis. The particle size of Al2O3 powder synthesised by the combustion process was 30 nm. XRD confirmed the presence of pure α-Al2O3. Combustion synthesised alumina (CSA) powder was codeposited in the nickel matrix at various current densities, as in the case of nickel. Similarly, commercially available 0·05 μm Al2O3 containing a mixture of α and β phases was codeposited in nickel matrix. The Ni–Al2O3 nanocomposite coatings were characterised by XRD, microhardness measurement and image analysis. The results obtained with nickel and Ni–Al2O3 composite coatings are compared.
Fabrication, development and characterisation of calcium phosphate based bioceramic coatings on 316L stainless steel for biomedical applications
Authors: Prabakaran K. , Vijayalakshmi U. , Rajeswari S.
Published: August 2005

Hydroxyapatite (HAP) was synthesised by a precipitation method, using naturally available chicken eggshell (Ca source) and phosphoric acid (P source). The synthesised powder was electrophoretically deposited on 316L stainless steel (316L SS). The chemical composition of the synthesised powder was analysed. Ca was estimated by conventional EDTA titration and P by a gravimetric method. The Ca/P ratio was found to be 1·67, which resembles the stoichiometric HAP ratio. Fourier transform infrared (FT-IR) and powder X-ray diffraction (XRD) techniques were employed to confirm HAP formation. FT-IR spectra showed the characteristic peaks for phosphate and hydroxyl groups. The XRD results revealed that the major characteristic peaks of HAP appear in the regions of approximately 26°, 28°, 29°, 30–35°, 39°, 46°, 49° and 50° (2 θ) and also indicated that no impurities are formed during HAP formation. The in vitro evaluation of HAP coated 316L SS was performed in simulated body fluid (Ringer's solution) of pH 7·4 at 37°C in a thermostatic water bath through cyclic polarisation, and the results indicated that the HAP coated 316L SS has better corrosion resistance than uncoated 316L SS.
Corrosion behaviour of aluminium in rain water containing garlic extract
Authors: Lakshmi Priya S. , Chitra A. , Rajendran S. , Anuradha K.
Published: August 2005

The inhibition efficiency of an aqueous extract of garlic in controlling corrosion of aluminium immersed in sodium hydroxide solution at pH 11 and 12, in the absence and presence of Zn2+, was evaluated by the weight loss method. At pH 11, the extract accelerated corrosion of aluminium in the absence and presence of Zn2+. The influences of N-cetyl- N,N,N-trimethylammonium bromide (CATB) (a biocide and a cationic surfactant) and immersion period on the inhibition efficiency were investigated. The influence of sodium sulphite, an oxygen scavenger, on the inhibition efficiency of the inhibitor system revealed that transport of inhibitor towards the metal surface plays a greater role than the removal of oxygen from the aqueous solution in determining the inhibition efficiency of the system. The protective film was analysed with the use of Fourier transform infrared spectra.
Surface modified silica gel for extraction of metal ions: An environment friendly method for waste treatment
Authors: Sharma R. K. , Mittal S. , Azami S. , Adholeya A.
Published: August 2005

A surface modified silica gel chelating resin was synthesised by immobilising tetracycline (TCN) on the surface of modified silica gel to produce a granular sorbent for the adsorption and estimation of copper, nickel and cadmium. Metal ions were quantitatively retained on the column packed with immobilised silica gel in the pH ranges of 5·0–6·5 for Cu, 6·8–7·8 for Ni and 6·6–7·8 for Cd. The distribution coefficient D determined for each metal ion was as follows (mL g−1): Cu, 2·45 × 102; Ni, 1·84 × 102; Cd, 2·33 × 102. Methods have been developed to determine copper, nickel and cadmium in steel, medicine tablets, alloys and river water samples. Molecular modelling studies were also performed on TCN-imobilised silica gel for gaining an insight into the active structure of TCN on the silica surface.
Electron beam evaporated rigid optical solar reflectors for space applications
Authors: George J. , Babu N. J.
Published: August 2005

Rigid optical solar reflectors (OSRs) for space applications were developed by using the electron beam evaporation technique. The component layers of the full stack were optimised for their electrical and optical properties. Thin films of Ta2O5 show absorption in the ultraviolet–visible range at high substrate temperatures, which can be eliminated by deposition at an oxygen partial pressure of >4 × 10−5 torr. Under optimised deposition conditions, indium–tin oxide (ITO) films have a sheet resistance Rsh of <0·95 kΩ/□ and a transmittance of <95% in the visible region. The electrical and optical properties of the OSR stacks were investigated as a function of various deposition parameters, such as substrate temperature, thickness and deposition rate. It was found that the functional properties of the OSRs developed with the electron beam technique are equivalent to those of the rigid OSRs deposited by the sputtering technique. A solar absorptance αs value of <0·047 and a sheet resistance Rsh value of <3 kΩ/□ were obtained for the OSR deposited under the optimised conditions. The samples were found to be environmentally durable.
The natural lighting in the dome of the Rotunda at Thessaloniki
Authors: Iliadis IG
Published: August 2005

The initial results of this study were published in 2001. This paper presents the second part of the study and examines the distribution of the light in relation to the building and time and definition—conscious or not—of a ‘light management’ system. Also, the present study is based partly on a series of measurements of illuminance at certain fixed points in the interior of the monument and partly on observations of the path of the sun during the different seasons of the year, as well as the direction of the sun’s rays in the interior of the Rotunda.
Preferred task-lighting levels in an industrial work area without daylight
Authors: Juslén HT , Wouters MCHM , Tenner AD
Published: August 2005

In a luminaire factory an experiment was performed to determine the preferred lighting levels in an industrial work environment. A dimmable task-lighting system was installed above 10 individual assembly workstations. The illuminances selected by the users (regular workers) were recorded. The differences between the individual settings were large. Weak, but significant trends in using different lighting levels at different times during the working day were found. Subjects exhibited different weekly rhythms in their preferred illuminance, and as a group they showed a tendency to use lower lighting levels on Fridays than on Thursdays during the summer, and the reverse during the winter. There was also a trend towards using lower illuminances on the task in the summer than in the winter.
Models of optical characteristics of barrel-vault skylights: development, validation and application
Authors: Laouadi A
Published: August 2005

By admitting natural light deep into a building and connecting occupants with the outside, skylights can improve the aesthetic look of buildings and increase occupant satisfaction. In addition, by allowing the entry of natural light electric light levels can be reduced thereby leading to energy savings. However, the potential energy benefits and amenities of skylights have not been fully exploited in today’s building design due to some theoretical and technical challenges. The lack of design tools is one of the major hurdles building designers face to adopt such products and quantify their energy benefits. The optical characteristics of skylights are the significant factors affecting their energy benefits. Recognizing this gap, the SkyVision tool was developed to assist skylight manufacturers and building designers in developing appropriate skylight designs for given building types and daylighting applications. This paper describes the models implemented in SkyVision to compute the optical characteristics of barrel-vault skylights with clear, fully translucent or partially diffusing glazing under beam and diffuse light. The models are based on the ray-tracing technique. Under diffuse light, two models are developed: (1) a luminance-based model when the sky luminance distribution is known; and (2) an illuminance-based model when the illuminance on a horizontal surface is known. The second model is simpler and faster and more suitable for annual performance calculation. Experimental measurements of the skylight transmittance were conducted under real sky conditions to validate the model predictions. The actual measurements compared reasonably well with the model predictions. The predictions from the luminance-based and illuminance-based models showed good agreement with each other. When applied to an example study, the models predicted that vault skylights with clear glazing are more effective than flat skylights with similar glazing in boosting the beam light transmittance, particularly in winter days. Translucent vault skylights are more effective than flat skylights with similar glazing in reducing solar heat gains, particularly in summer days. Translucent skylights may out-perform transparent skylights, particularly during sunny days in winter.
Urban poverty and health in developing countries: Household and neighborhood Effects
Authors: Montgomery Mark R. , Hewett Paul C.
Published: August 2005

In the United States and other high-income countries, there is intense scholarly and programmatic interest in the effects of household and neighborhood living standards on health. Yet few studies of developing-country cities have explored these issues. We investigated whether the health of urban women and children in poor countries is influenced by both household and neighborhood standards of living. Using data from the urban samples of 85 Demographic and Health Surveys and modeling living standards using factor-analytic MIMIC methods, we found that the neighborhoods of relatively poor households are more heterogeneous than is often asserted. Our results indicated that poor urban households do not tend to live in uniformly poor neighborhoods: about 1 in 10 of a poor household’s neighbors is relatively affluent, belonging to the upper quartile of the urban distribution of living standards. Do household and neighborhood living standards influence health? Using multivariate models, we found that household living standards are closely associated with three health measures: unmet need for modern contraception, attendance of a trained health care provider at childbirth, and young children’s height for age. Neighborhood living standards exert a significant additional influence in many of the surveys we examined, especially for birth attendance.
Empirical bayes estimation of demographic schedules for small areas
Authors: Assunção Renato M. , Schmertmann Carl P. , Potter Joseph E. , Cavenaghi Suzana M.
Published: August 2005

In this article, we analyze empirical Bayes (EB) methods for estimating small-area rate schedules. We develop EB methods that treat schedules as vectors and use adaptive neighborhoods to keep estimates appropriately local. This method estimates demographic rates for local subpopulations by borrowing strength not only from similar individuals elsewhere but also from other groups in the same area and from regularities in schedules across locations. EB is substantially better than standard methods when rates have strong spatial and age patterns. We illustrate this method with estimates of age-specific fertility schedules for over 3,800 Brazilian municipalities.
Household Production and Risk Management among Pastoral Communities in Samburu District, Kenya
Authors: Esilaba Moses O
Published: August 2005

Rangeland resources play a significant role in production activities and sustainability of livelihood among the pastoral communities. Factors that have adversely affected efficient utilization and have an ultimate impact on risk management include: conflicts, poor public service delivery, uneven resource utilization and limited asset diversification. This paper examines these factors in detail, and assesses their influence on household production. The objective of the study was to investigate the influence of household production on the ability of the pastoralists to manage risks. The findings and recommendations will be helpful to put in place strategies that will increase household production, minimize conflicts among the various resource users, promote sustainable use of natural resources, and serve as a step towards eradication of poverty. The study was carried out in Kirisia, Lorroki and Baragoi divisions of Samburu district. A survey was conducted using a structured questionnaire (248 households), together with personal interviews with key informants (30), and group discussions (7). Data analysis involved descriptive statistics and tests of relationships by use of correlation and regression analysis, using Statistical Package for the Social Sciences (SPSS). The results indicated that there was no significant relationship between household production and public service delivery, resource utilization, asset diversification and risk management. Household income and asset diversification was low (less than Kshs.20, 000 per year and 20% of investment levels), high illiteracy rate (80%), and thus increase in poverty. The pastoralists, therefore, had limited capacity to manage both environmental and human risks, hence their vulnerability to climatic stress. It is recommended that pastoral communities should diversify their production activities to reduce dependence on livestock, to alleviate poverty and enhance risk management.
Extra-Role Behaviour in Educational Organisations in Southern Ethiopia: Some Implications for School Effectiveness
Authors: Semela. Tesfaye
Published: August 2005

This study examines teachers' perceptions of extra-roles in school organisational contexts. The participants are 319 (234 male and 85 female) primary and secondary school teachers in Sidama Zone, Southern Ethiopia. The study employed a multi-dimensional extra-role behaviour (ERB) scale. Univariate, bivariate and multivariate statistical analyses procedures are used to answer the questions. The findings reveal that female teachers are generally more willing to volunteer for extra-roles towards the team (or co workers) than do males. Rural teachers, however, are less enthusiastic about involvement in extra roles towards the student and the organisation compared with their urban and suburban counterparts. In addition, job-related personal characteristics (i.e. personal teaching efficacy and job satisfaction) are observed to be significant predictors of all dimensions of ERB with a marginal contribution of socio-demographic variables. Implications of the findings for school effectiveness are adequately discussed.
Criminals or Victims? The Politics of Illegal Foreigners in Japan
Authors: Shipper Apichai W. (Apichai Wongsod)
Published: August 2005

Public opinion over illegal foreigners in Japan is highly contested. Some political leaders construct negative images of illegal foreigners as criminals, while activists portray them as victims. These activists provide an alternative source of information about the conditions of illegal foreigners and are an important counterweight to official Japan's more prejudiced activities. Consequently, Japanese attitudes toward illegal foreigners during the 1990s were mixed, with an increasing association of illegal foreigners and criminality and a rise in the perception of them as victims deprived of basic rights. Renewed efforts from state actors have further incited xenophobic attitudes toward illegal foreigners.
Progress and Love Marriage: Rereading Tanizaki Jun'ichiro's Chijin no ai
Authors: Suzuki Michiko
Published: August 2005

This article examines Tanizaki Jun'ichirō's Chijin no ai (A fool's love, 1924–25) and its conversation with the prominent cultural discourses of its time. I focus particularly on the ideas presented by writers such as Hiratsuka Raichō and Kuriyagawa Hakuson regarding "love marriage" (ren'ai kekkon), a practice idealized as both a marker for an advanced nation and a site enabling individuals to "progress" and heighten their characters (jinkaku). The novel parodically rewrites and actively reexamines these discourses in relation to contemporary values such as self-cultivation (shūyō) and cultural knowledge (kyōkō), asking what "progress" means within the rapidly changing social landscape of the 1920s.