bluuebunny/crossref_metadata_2025 huggingface dataset:
A teoria das cores de newton: um exemplo do uso da história da ciência em sala de aula
Authors: Silva Cibelle Celestino , Martins Roberto de Andrade
Published: September 2010

Neste artigo, discutiremos o trabalho sobre luz e cores de Newton publicado em 1672 para vermos exemplos de questões que podem ser abordadas em sala de aula através da História da Ciência. No entanto, alguns cuidados devem ser tomados para não apresentarmos uma visão distorcida do método científico e uma idéia mítica sobre a Ciência. Este estudo analisa o experimento principal de Newton cuja intenção era mostrar que a luz branca é uma mistura de raios com diferentes refrangibilidades. Embora atualmente essa teoria seja aceita e ensinada sem discussão, um estudo histórico crítico sobre ela levanta muitas questões que serão discutidas neste artigo.
Análise da relação entre força e movimento em uma revista de divulgação científica
Authors: Gomes Luciano Carvalhais , Fusinato Polônia Altoé , Neves Marcos César Danhoni
Published: September 2010

O objetivo desta pesquisa foi fazer uma análise crítica das concepções alternativas sobre força e movimento na revista Superinteressante. Para embasar essa análise, fizemos uma revisão bibliográfica sobre o tema, abrangendo desde a teoria dos movimentos naturais de Aristóteles até as três leis de Newton. Em seguida, fizemos uma comparação das concepções encontradas em várias pesquisas sobre esse assunto com as desses pensadores. Guiados por essa revisão bibliográfica, concluímos que muitas das concepções dos estudantes sobre força e movimento estão presentes na revista, mas em percentagem menor, comparadas com as encontradas nessas pesquisas. O que exige, dos educadores interessados na aprendizagem significativa dos seus alunos, cuidados especiais em sua utilização como um recurso didático.
Aulas de ciências na oitava série do ensino fundamental: uma proposta de projeto curricular como processo em construção
Authors: Silva Daniela Rodrigues da , Del Pino José
Published: September 2010

Este artigo apresenta o planejamento e desenvolvimento de um projeto curricular construído enquanto processo, com o intuito de organizar estratégias metodológicas, entre elas a resolução de problemas, e completar, assim, uma proposta pedagógica com pressupostos construtivistas. A pesquisa foi realizada com uma turma de oitava série do Ensino Fundamental, na disciplina de ciências. A participação de um professor pesquisador, capaz de realizar a interlocução entre teoria e prática, e o diálogo entre professora e alunos tornaram-se elementos determinantes para a estruturação do projeto curricular, buscando a abordagem de conceitos científicos ao mesmo tempo em que necessidades e interesses do grupo em estudo pudessem ser debatidos. A interação em sala de aula e as produções dos alunos, a partir das estratégias utilizadas, foram componentes de análise e discussão para direcionar o desenvolvimento da proposta, e modificaram o comportamento e os hábitos dos sujeitos envolvidos no processo.
Imagens em narrativa: contraposição cultural e interdisciplinaridade no ensino fundamental
Authors: Paleari Lucia Maria , Biz Antonio Carlos
Published: September 2010

Com as transformações pelas quais passa o conhecimento científico na atualidade, a narrativa transformou-se em tema de relevância, quando se pesquisam questões relativas à construção de significado na experiência humana. Investigada como técnica de ensino junto a alunos de 6ª série de Botucatu, São Paulo, os quais foram confrontados com o ambiente urbano de Salvaterra, Ilha de Marajó, revelou que a força das oposições binárias, previstas teoricamente, estimula a reelaboração de conceitos prévios, revisão e resignificação de valores e de condicionamentos sociais. A narrativa como técnica de ensino propicia aprendizagem efetiva, com o espectador organizando a sequência de imagens apresentada e fazendo emergir significado de acordo com as suas experiências e estrutura cognitiva.
Glass barrier ribs for a transparent AC plasma display
Authors: Lee Sung‐Min , Oh Seung Hwa , Kim Seung Hun , Choi Kyung Cheol
Published: September 2010

Abstract— Transparent glass barrier ribs are proposed for the development of a transparent plasma display. Glass barrier ribs were fabricated via a wet‐etching process with a 20% hydrofluoric acid. Two different etching methods for glass barrier ribs are investigated: a single‐sided etching method and a double‐sided etching method. Simulation and measurement results show that glass barrier ribs formed by the double‐sided etching method are more transparent compared to those formed by a single‐sided etching method. A fabricated transparent AC plasma display with glass barrier ribs showed good transparency and was operated by using a conventional driving scheme.
Transfer‐curve assessment of oxide thin‐film transistors
Authors: Wager John F.
Published: September 2010

Abstract— Oxide electronics is an emerging area that is well positioned to strongly and positively impact next‐generation display technology. A metal‐oxide thin‐film transistor (TFT) is the fundamental component of oxide electronics. Unfortunately, some of the claims made in the literature about the performance of oxide TFTs are, in this author's opinion, unreliable. This is true of turn‐on voltage, subthreshold swing, and, especially, channel mobility. Measurement artifacts can lead to unreliable performance estimates. The goal of this contribution is to enumerate some of these artifacts and to outline a general testing procedure for avoiding common oxide‐TFT assessment pitfalls.
Uniformity and bias‐temperature instability of bottom‐gate zinc oxide thin‐film transistors (ZnO TFTs)
Authors: Furuta Mamoru , Kimura Mutsumi , Hiramatsu Takahiro , Nakanishi Takashi , Li Chaoyang , Hirao Takashi
Published: September 2010

Abstract— Short‐range uniformity and bias‐temperature (BT) instability of ZnO TFTs with SiOx/SiNx stacked gate insulators which have different surface treatments have been investigated. The short‐range uniformity of ZnO TFTs was drastically improved by N2O plasma treatment of the gate insulator. The variation in the gate voltage where a drain current of 1‐nA flows (Vgs at an Ids of 1 nA) was dramatically reduced from ±1.73 V to ±0.07 V by N2O plasma treatment of the gate insulator. It was clarified that the variations in the subthreshold characteristics of the ZnO TFTs could be reduced by N2O plasma treatment of the gate insulator due to a decrease in the variation of trap densities in deep energy levels from 0.9–2.0 × 1017 to 1.2–1.3×1017 cm−3‐eV−1. From the BT stress tests, a positive shift of Vgs at an Ids of 1 nA could be reduced by N2O plasma treatment of the gate insulator due to a decrease in the charge traps in the gate insulator. When the gate‐bias stress increases, state creation occured in the ZnO TFTs in addition to the charge trapping in the gate insulator. However, N2O plasma treatment of the gate insulator has little effect on the suppression of the state creation in ZnO TFTs under BT stress. The surface treatment of the gate insulator strongly affects the short‐range uniformity and the BT instability of Vth in the ZnO TFTs.
Device reliability under electrical stress and photo response of oxide TFTs
Authors: Park Sang‐Hee Ko , Ryu Min‐Ki , Yoon Sung‐Min , Yang Shinhyuk , Hwang Chi‐Sun , Jeon Jae‐Hong
Published: September 2010

Abstract— The stability of oxide TFTs has been the main focus of this research and is probably the most crucial requirement for the successful application to flat‐panel displays. Although the high Fermi level of oxide semiconductors makes TFTs basically stable under electrical stress, the device reliability under diverse variations of electrical stress is affected by materials such as active semiconductors and gate insulators, processes for the formation of back/front channels and passivation layers, and device configurations among other things. How these factors affect the device reliability have been investigated and a review of the stability is presented. In addition, several categories of the light instability of oxide TFTs is presented and the origin is discussed.
Interface and bulk effects for bias—light‐illumination instability in amorphous‐In—Ga—Zn—O thin‐film transistors
Authors: Nomura Kenji , Kamiya Toshio , Hosono Hideo
Published: September 2010

Abstract— Positive‐current‐bias (PB) instability and negative‐bias—light‐illumination (NBL) instability in amorphous‐In—Ga—Zn—O (a‐IGZO) thin‐film transistors (TFTs) have been examined. The channel‐ thickness dependence indicated that the Vth instability caused by the PB stress is primarily attributed to defects in the bulk a‐IGZO region for unannealed TFTs and to those in the channel—gate‐insulator interface for wet‐annealed TFTs. The interface and bulk defect densities (Dit and Nss, respectively) are Dit = 4.8 × 1011 cm−2/eV and Nss = 7.0×1016 cm−3/eV for the unannealed TFT, which increased to 5.2×1011 cm−2/eV and 9.8×1016 cm−3/eV, respectively, by the PB stress test. These are reduced significantly to Dit = 0.82×1011 cm−2/eV and Nss = 3.2×1016 cm−3/eV for the wet‐annealed TFTs and are unchanged by the PB stress test. It was also found that the photo‐response of a‐IGZO TFTs begins at 2.3 eV of photon excitation, which corresponds to subgap states observed by photoemission spectroscopy. The origin of the NBL instability for the wet‐annealed TFTs is attributed to interface effects and considered to be a trap of holes at the channel‐gate—insulator interface where migration of the holes is enhanced by the electric field formed by the negative gate bias.
Influence of channel‐deposition conditions and gate insulators on performance and stability of top‐gate IGZO transparent thin‐film transistors
Authors: Hsieh Hsing‐Hung , Wu Cheng‐Han , Chien Chih‐Wei , Chen Chang‐Ken , Yang Chao‐Shun , Wu Chung‐Chih
Published: September 2010

Abstract— Amorphous‐oxide‐semiconductor thin‐film transistors (TFTs) have gained wide attention in recent years due to their many merits. In this paper, a series of top‐gate transparent thin‐film transistors (TFTs) based on amorphous‐indium—gallium—zinc—oxide (a‐IGZO) semiconductors have been fabricated and investigated. Specifically, low‐temperature SiNx and SiOx were used as the gate insulator and different Ar/O2 gas‐flow ratios were used for a‐IGZO channel deposition to study the influences of gate insulators and channel‐deposition conditions. In addition to the investigation of device performance, the stability of these TFTs was also examined by applying constant‐current stressing. It was found that a high mobility of 30‐45 cm2/V‐sec and small threshold‐voltage shift in constant‐current stressing can be achieved using SiNx with suitable hydrogen‐content stoichiometry as the gate insulator and the carefully adjusted Ar/O2 flow ratio for channel deposition. These results may be associated with hydrogen incorporation into the channel, the lower defect trap density, and the better water/oxygen barrier properties (impermeability) of the low‐temperature SiNx.
Effects of gate‐bias stress on ZnO thin‐film transistors
Authors: Su Liang‐Yu , Lin Hsin‐Ying , Wang Sung‐Li , Yeh Yung‐Hui , Cheng Chun‐Cheng , Peng Lung Han , Huang Jian‐Jang
Published: September 2010

Abstract— The effects of gate‐bias and thermal stress on the stability issues of zinc oxide thin film transistors (ZnO TFTs) deposited on glass substrates were investigated. The shift in threshold voltage for devices undergoing various post‐growth annealing conditions using a stretched‐exponential formalism was analyzed. The analysis indicated that the extracted parameters such as the time constant and the effective energy barrier (Eτ) can be correlated to the device trap states associated with the annealing conditions. Improvement in the channel conductance and interface quality, hence the resultant device stability, can therefore be resumed when subject to a thermal treatment at 400°C for 30 minutes compared with those annealed for a shorter time.
OLED‐based pico‐projection system
Authors: Großmann Constanze , Riehemann Stefan , Notni Gunther , Tünnermann Andreas
Published: September 2010

Abstract— Two pico‐projection systems, a monochrome green and a full‐color system, based on high‐efficiency OLED microdisplays (VGA; pixel size, 12 μm) are presented. Both optical systems are described by a numerical aperture of about 0.3, a magnification of 15x, and a working distance of 300–360 mm. The frequency limit of both systems is 42 cycles/mm at an image contrast of about 60%. The monochrome projection system with a volume smaller than 10 cm3 consists of one green OLED and a projection lens with five elements. The measured luminance in the image plane is about 0.061 lm. The image has a diagonal of 150 mm with a working distance of about 300 mm and has a considerable image contrast of 396:1. The second system combines three high‐brightness OLEDs, red, green, and blue colored, together with a projection lens and an image‐combining element, and an X‐Cube to achieve full‐color projection. The estimated luminance value for the three‐panel projection unit with an OLED luminance of 10,000 cd/m2 for each display will be about Φcalculated = 0.147 lm. In this paper, the system concepts, the optical designs, and the realized prototypes of the monochrome and full‐color projection system are presented.
An affordable surround‐screen virtual reality display
Authors: Cruz‐Neira Carolina , Reiners Dirk , Springer Jan P.
Published: September 2010

Abstract— Building a projection‐based virtual reality display is a time‐, cost‐, and resource‐intensive enterprise, and many details contribute to the final display quality. This is especially true for surround‐ screen displays where most of them are one‐of‐a‐kind systems or custom‐made installations with specialized projectors, framing, and projection screens. In general, the costs of acquiring these types of systems have been in the hundreds and even millions of dollars, specifically for those supporting synchronized stereoscopic projection across multiple screens. Furthermore, the maintenance of such systems adds an additional recurrent cost, which makes them hard to afford for general introduction in a wider range of industry, academic, and research communities. A low‐cost easy‐to‐maintain surround‐screen design based on off‐the‐shelf affordable components for the projection screens, framing, and display systems is presented. The resulting system quality is comparableto significantly more expensive commercially available solutions. Additionally, users with average knowledge can implement this design, and it has the added advantage that single components can be individually upgraded based on necessity as well as available funds.
An embedded reset driver for digital micromirror devices (DMDs)
Authors: Wang Jianbai , Huffman James , Pinheiro Paulo , Hall James
Published: September 2010

Abstract—A digital micromirror device (DMD) is a micromachined high‐density light‐modulating system widely used in front projectors, high‐definition TVs, and digital cinemas. Although the high‐speed memory and digital control electronics have long been integrated underneath the micromirror array, high‐voltage reset waveforms have to be provided separately and synchronized with the DMD chip to actuate the micromirrors. Using drain‐extended transistors, the high‐voltage driver electronics are successfully integrated on DMDs to generate local reset waveforms having voltage variations up to 30 V at a fast slew rate. At fast‐charging/discharging rates, the transistor reliability requirements are still satisfied and the driver electronics maintain low average current consumption.
Egg performance, egg quality, and nutrient utilization in laying hens fed diets with different levels of rapeseed expeller cake
Authors: SWIATKIEWICZ S. , KORELESKI J. , ARCZEWSKA-WLOSEK A.
Published: September 2010

The aim of this study was to evaluate the effect of different levels of rapeseed expeller cake (RC) in the diet of laying hens on egg performance, egg quality, retention and excretion of nitrogen, calcium and phosphorus, and metabolizability of energy. The experiment was carried out with 72 Bovans Brown hens, from 28 to 53 weeks of age. Experimental treatment consisted of four isonitrogenous and isocaloric corn-soybean diets (as calculated: 17% crude protein, 11.6 MJ/kg metabolizable energy, 0.81% lysine, 0.36% methionine, 3.60% calcium and 0.37% available phosphorus), containing 0, 4, 6 or 8% RC. The RC used was produced from double zero rapeseed and contained 29.3% crude protein, 17.4% crude fat, 10.8% crude fibre, 0.63% calcium, 0.97% phosphorus, 1.91% lysine and 0.84% methionine. During the experimental period, the dietary level of RC had no significant effects on egg performance and egg quality parameters. Boiled eggs from hens fed a diet with 8% RC were characterized by an inferior flavour to those from other groups. There were no treatment effects on nitrogen balance or metabolizability of energy, though the highest dietary level of RC negatively affected retention and excretion of calcium and phosphorus.;
Meat quality and fatty acid profile of M. longissimus dorsi of growing bulls under insulated, uninsulated and outdoor housing conditions
Authors: HUUSKONEN A. , JOKI-TOKOLA E. , HONKAVAARA M.
Published: September 2010

The objective of the present study was to compare the colour, chemical composition, meat quality and fatty acid profile of the longissimus dorsi (LD) muscle of growing bulls housed in an insulated tie-stall, an uninsulated barn or a forest paddock. Two housing experiments were conducted at the North Ostrobothnia Research Station of MTT Agrifood Research Finland in Ruukki (64°44N, 25°15E). The first experiment was conducted from November 1999 to October 2000 and comprised 30 Hereford bulls, the second from November 2000 to December 2001 with 30 Ayrshire bulls. In both experiments the bulls were divided into six groups of five animals according to live weight and the groups were randomly allotted to one of three treatments: tie-stall in an insulated barn (IB bulls, ten animals/individual stall), uninsulated barn (UB bulls, five animals/pen, two pens) and forest paddock (PAD bulls, five animals/paddock, two paddocks). Nine carcasses from experiment 1 (three/treatment) and twelve from experiment 2 (four/treatment) were randomly selected for meat quality analyses. After slaughter, the carcasses were cooled for 24h at 2 °C and LD samples were taken by complete cross-section between the 12th and 13th ribs. The results were calculated across the two experiments and analysed as one data. There were no differences between housing environments in temperature or pH of the LD or meat moisture, fat or protein composition of the LD. Instead, the myoglobin content of the LD was 21% higher in PAD bulls than in IB bulls (p < 0.05). Between IB and UB bulls there was no difference in meat myoglobin content and there were no significant (p < 0.05) differences between housing environments in the colour of the LD. However, the muscle tended to be 6% lighter (L-value) in IB bulls than in PAD bulls (p = 0.09). There were no significant differences in shear force or sensory analysis (tenderness, juiciness, overall flavour) between treatments. The LD of the PAD bulls contained a higher proportion of 18:2 and 18:3 fatty acids compared to that of IB bulls (p < 0.05). There were no significant differences in the saturated fatty acid (SFA) or monounsaturated fatty acid proportions of the LD between treatments. Instead, the polyunsaturated fatty acid (PUFA) proportion of the LD was 34% higher in PAD bulls than in IB bulls (p < 0.05). The PUFA:SFA ratio was higher in PAD bulls than in IB bulls (p < 0.05) but there was no difference in the PUFA:SFA ratio between UB and IB bulls. In conclusion, there were no important effects of housing system on the meat quality characteristics of the LD, although according to meat fatty acid profiles, outdoor housed bulls produced meat with a higher PUFA:SFA ratio than tethered bulls in an insulated barn.;
Comparison of different models for the estimation of genetic parameters of body weight traits in Moghani sheep
Authors: HOSSEIN-ZADEH N.G. , ARDALAN M.
Published: September 2010

Genetic parameters for birth weight (BW), 3-month weight (3MW), 6-month weight (6MW), 9-month weight (9MW) and yearling weight (YW) in Iranian Moghani sheep were estimated using restricted maximum likelihood procedure of MTDFREML program. The data and pedigree information used in this research were collected at the Breeding station of Moghani sheep (Ardebil province, Iran) during 19872005. Six different animal models were fitted, differentiated by including or excluding maternal effects, with and without covariance between maternal and direct genetic effects. The estimates for direct heritability ranged from 0.31 to 0.54, 0.21 to 0.34, 0.13 to 0.25, 0.11 to 0.22 and 0.10 to 0.17 for BW, 3MW, 6MW, 9MW and YW, respectively. The estimates were substantially higher when maternal effects, either genetic or environmental, were ignored in the model. The results of this study show that full models with maternal genetic and environmental effects gave the most accurate estimates for body weight traits in Moghani sheep.;
Improving the quality of dry-cured sausages using pork from rustic breeds
Authors: BANON S. , BEDIA M. , ALMELA E.
Published: September 2010

The use of pork from rustic pig breeds was tested to improve the quality of dry-cured fermented sausages. The quality of a salchichon/salami-type sausage manufactured with pork from Chato Murciano breed (CM) and Early White pig (EW) (Large White ~ Landrace breed) was compared. CM pork improved several quality characteristics of dry-cured fermented sausage. Significant (p . 0.05) differences between mean CM and EW values were found for total lipids, ash, collagen, water activity, total acidity, CIELab colour, proteolysis, fat acidity, fatty acid profile, total viable counts, lactic acid bacteria, Micrococacceae, moulds and yeasts, colour, odour, flavour, fattiness and acceptance. CM mainly intensified the reddening of sausage cuts and increased monounsaturated acids in fat. Acceptance was also better for CM, although odour and flavour were only slightly improved. The production of high-quality specialities of dry-cured meat products can contribute to the sustainable production of CM and similar rustic pig breeds, maintaining the genetic diversity of pig species.;
The influence of raw grass pea (Lathyrus sativus L.) seeds on growth performance and biochemical and haematological parameters in the blood of grower-finisher pigs
Authors: WINIARSKA-MIECZAN A. , KWIECIEN M.
Published: September 2010

The aim of the present study was to examine the influence of raw seeds of grass pea (Lathyrus sativus L.) in feed mixtures for grower-finisher pigs on growth performance, and biochemical and haematological parameters in their blood, as well as on the weight of the liver and the kidney. The experiment was performed on 96 grower-finisher pigs of (Polish Landrace × Polish Large White) × Pietrain, weighing from 25 to ca. 100 kg. The pigs were divided into four diet groups. The feed compound of the control group contained extracted soybean meal. In experimental groups soybean meal protein was replaced by raw grass pea seeds in quantities of 50% in grower and/or finisher diet, and 100% in both fattening period. The use of raw grass pea seeds amounting to 50% of protein feeds in finisher diet did not result in lower growth performance in comparison to the control group. However, the fatteners fed grass pea seeds amounting to 50% of protein feedstuffs in both fattening periods revealed the highest feed and energy intake per kg of live weight gain, compared to the group feed grass pea only in the second phase of the fattening period. A higher share of grass pea seeds in the mixture led to weaker growth performance and carcass characteristics. Hypertrophy of kidney and liver was noted in the animals which were fed with raw seeds of grass pea amounting to 100% of protein feeds. Also, hyperactivity of ALAT, ASAT and alkaline phosphatase was observed in the animals serum. No negative influence of applying raw seeds of grass pea amounting up to 50% of protein feeds in grower and/or finisher periods on the parameters examined was noted.;
Neural Stem Cells: New Hope for Successful Therapy
Authors: English Denis , Anand Akshay , S.Verma Rama , Glück Stefan
Published: September 2010

The devastation caused by disruption of the central nervous system and the increased prevalence of
chronic neural diseases in our aging population led to enthusiastic and rapid acceptance of neural stem cells as
an effective tool to reverse central nervous system pathology over a decade ago. Shortly after human
embryonic stem cells were identified, results which held that functional neurons generated from stem cells
reversed severe damage to the central nervous system were widely disseminated and avidly endorsed.
Subsequent reports claimed neural localization and proliferation of adult stem cells, trans-differentiation of
mesenchymal stem cells into functional neurons, and stunning therapeutic effects of human neural stem cells in
animal models.

Despite these claims, effective therapy with neural stem cells has not been realized. Early results have been
attributed to factors released by infused cells and investigator bias but not to tissue regeneration. The identity of
stem cell progeny identified as neurons by antigen expression and morphology has been questioned, leading to
the re-interpretation of these results by many of the investigators who first reported them. Therapeutic
expectations have subsided while reports of success in animal models continue to appear. The thought that
neural stem cells, as currently defined, will reverse brain injury or pathology has been largely dismissed.

Despite these diminished expectations, herein we note that regenerative cells, or structures that mimic the
function regenerative cells possess, are present in germinal areas of the adult human brain, albeit in limited
numbers. Evidence does suggest that damaged brain tissue does, in some patients, regenerate with recovery of
lost function. These cellular entities have not been widely studied, characterized or cultured, but they may be
similar to structures generated in neural tissue of primitive vertebrates which have a remarkable capability to
regenerate intact, functional brain. These structures can potentially be expanded using methods that differ
vastly from stem cell culture methods employed to date. Successfully expanded and stored, these structures
may provide an effective means to regenerate brain tissue after stroke and traumatic brain injury in humans.
The panel of resolution methods
Authors: David Claire
Published: September 2010

This chapter presents the main classical methods used to obtain solutions of Classical
nonlinear evolution equations.
Asymptotic behavior of solitary waves
Authors: David Claire , Meng Qingguo
Published: September 2010

This chapter presents a study of the asymptotic behavior of solitary waves.
Attractor and traveling wave solutions for 3D Ginzburg-Landau type equation
Authors: Lu Shujuan
Published: September 2010

In this chapter, we consider the initial value problem of a Ginzburg- Landau equation
with spatial periodicity condition in three dimension. Firstly, In Section 2 we prove the
existence of local solution (see Theorem 2.1). Furthermore, the existence and uniqueness
of global solution are proved by making a prior estimate for solution u(t) (see Theorem
2.2 and 2.3). In Section 3, the existence of global attractor and upper bound estimates for
its Hausdorff dimensions and fractal dimensions are obtained (see Theorem 3.2 and 3.3).
Then, in Section 4 the existence of finite dimensional exponential attractor is proved (see
Theorem 4.2). In Section 5, we construct a fully discrete Fourier spectral approximation
scheme for problem (1.4)-(1.6) and then prove the existence and convergence of approximate
attractors (see Theorem 5.2.1 and 5.3.2) are presented. Moreover, the long-time
Comment on Shiller: Urban Density Drives Housing Price Increases
Authors: Bossons John
Published: September 2010

Robert Shiller's analysis misses the fact that house prices depend on urban density, not just price of agricultural land, according to John Bossons of the University of Toronto.
Unified Power Quality Conditioner Using a Fuzzy Controller
Authors: Patel Chirag , Mahanty Ranjit
Published: September 2010

The paper presents a three-phase unified power quality conditioner using a fuzzy controller. The fuzzy controller replaces the conventional PI controller in this work. The results obtained through the fuzzy controller are found superior to those obtained through conventional PI controller in terms of dynamic response. This is because of the fact that the fuzzy controller is based on a linguistic variable set theory and does not require a mathematical model of the system. Moreover, the tedious method of tuning the PI controller is not required in case of fuzzy controller. Simulations are carried out using MATLAB/Simulink to validate the theoretical findings.
Gas and Optical Sensing Technology for the Field Assessment of Transformer Oil
Authors: Amrulloh Yusuf , Abeyratne Udantha , Ekanayake Chandima
Published: September 2010

Oil testing has found widespread use in assessing the quality of the insulation system of a transformer. Techniques such as Dissolved Gas Analysis (DGA) have been proven to be reliable in this task, but are expensive, laborious and time consuming. It is also not available for field use. This paper proposes the combined use of gas and optical sensing technology for the testing of transformer oil. It provides a low-cost, portable technology capable of fast and reliable field screening of transformers. The method consists of an oil handling and unit as well as a gas and optical sensor array. Gas sensing targets moisture, hydrocarbons and other volatile compounds dissolved in transformer oil; optical measurements provide information on the absorption properties of transformer oil, within a band of frequencies made possible by the recent advances in Blue-LED technology. These measurements are then combined through a pattern recognition system producing a collective decision on the state of the transformer. The performance of the method was evaluated on a database of 26 transformer oil samples, using a leave-one-out validation technique. Our results indicated that the method was capable of categorizing transformer oil into three classes, acceptable, marginal and bad with reasonable accuracy, based on the acidity and furfuraldehyde levels estimated from gas-optical measurements. The results need to be further validated using a larger database of transformer oil samples.
I Scratched Yours: The Prevalence of Reciprocation in Feedback Provision on eBay
Authors: Jian Lian , MacKie-Mason Jeffrey K , Resnick Paul
Published: September 2010

Many online systems for bilateral transactions elicit performance feedback from both transacting partners. Such bilateral feedback giving introduces strategic considerations. We focus on reciprocity in the giving of feedback: how prevalent a strategy of giving feedback is only if feedback is first received from one's trading partner. The overall level of feedback activity clearly depends on the prevalence of the reciprocation strategy: in a market with many reciprocators and few unconditional feedback providers, the equilibrium quantity of feedback can be quite low. We estimate the prevalence of such reciprocation in one market, eBay. Reciprocation cannot be directly distinguished from late feedback that was not conditioned on the partner having provided feedback. We develop a model that distinguishes the two by exploiting information about the timing of feedback provision when the partner does not provide feedback. We find that buyers and sellers on eBay used the reciprocate only strategy about 20-23% of the time. We also measure the extent to which the prevalence of these strategies changes with the experience levels of the two parties and with the item price.
Differential Adaptation of Human Gut Microbiota to Bariatric Surgery–Induced Weight Loss
Authors: Furet Jean-Pierre , Kong Ling-Chun , Tap Julien , Poitou Christine , Basdevant Arnaud , Bouillot Jean-Luc , Mariat Denis , Corthier Gérard , Doré Joël , Henegar Corneliu , Rizkalla Salwa , Clément Karine
Published: September 2010

OBJECTIVE

Obesity alters gut microbiota ecology and associates with low-grade inflammation in humans. Roux-en-Y gastric bypass (RYGB) surgery is one of the most efficient procedures for the treatment of morbid obesity resulting in drastic weight loss and improvement of metabolic and inflammatory status. We analyzed the impact of RYGB on the modifications of gut microbiota and examined links with adaptations associated with this procedure.

RESEARCH DESIGN AND METHODS

Gut microbiota was profiled from fecal samples by real-time quantitative PCR in 13 lean control subjects and in 30 obese individuals (with seven type 2 diabetics) explored before (M0), 3 months (M3), and 6 months (M6) after RYGB.

RESULTS

Four major findings are highlighted: 1) Bacteroides/Prevotella group was lower in obese subjects than in control subjects at M0 and increased at M3. It was negatively correlated with corpulence, but the correlation depended highly on caloric intake; 2) Escherichia coli species increased at M3 and inversely correlated with fat mass and leptin levels independently of changes in food intake; 3) lactic acid bacteria including Lactobacillus/Leuconostoc/Pediococcus group and Bifidobacterium genus decreased at M3; and 4) Faecalibacterium prausnitzii species was lower in subjects with diabetes and associated negatively with inflammatory markers at M0 and throughout the follow-up after surgery independently of changes in food intake.

CONCLUSIONS

These results suggest that components of the dominant gut microbiota rapidly adapt in a starvation-like situation induced by RYGB while the F. prausnitzii species is directly linked to the reduction in low-grade inflammation state in obesity and diabetes independently of calorie intake.
Transmission of light in crystals with different homogeneity: using Shannon index in photonic media
Authors: Bellingeri Michele , Longhi Stefano , Scotognella Francesco
Published: September 2010

Light transmission in inhomogeneous photonic media is strongly influenced by the distribution of the diffractive elements in the medium. Here it is shown theoretically that, in a pillar photonic crystal structure, light transmission and homogeneity of the pillar distribution are correlated by a simple linear law once the grade of homogeneity of the photonic structure is measured by the Shannon index, widely employed in statistics, ecology and information entropy. The statistical analysis shows that the transmission of light in such media depends linearly from their homogeneity: the more is homogeneous the structure, the more is the light transmitted. With the found linear relationship it is possible to predict the transmission of light in random photonic structures. The result can be useful for the study of electron transport in solids, since the similarity with light in photonic media, but also for the engineering of scattering layers for the entrapping of light to be coupled with photovoltaic devices.
Early days of coherence theory and the first Rochester conference on coherence
Authors: Wolf E.
Published: September 2010

The terms coherence and correlations seem to have entered the optics vocabulary about the beginning of the twentieth century, many years after Maxwell discovered that light was an electromagnetic phenomenon. Prior to that time there were only a few investigations, which have a bearing on this subject. The first one was made by a distinguished French optical scientist E. Verdet who around 1865 asked a question which is equivalent to the following: if sunlight illuminates directly two pinholes in an opaque screen, how close must the pinholes be, so that the light which emerges from them can form interference fringes on superposition? He estimated the distance to be about 1/50 millimeter. In modern language this small distance is the diameter of the area of coherence formed by sunlight on the surface of the earth.
Valentin A. Fabrikant: negative absorption, his 1951 patent application for amplification of electromagnetic radiation (ultraviolet, visible, infrared and radio spectral regions) and his experiments
Authors: Lukishova Svetlana G.
Published: September 2010

This paper is devoted to Moscow physicist Valentin A. Fabrikant who is known for his 1939 thesis with suggestion of experiments on light amplification directly proving the existence of negative absorption in gas discharge, his 1951 patent application (jointly with M. M. Vudynsky and F. A. Butaeva) for amplification of electromagnetic radiation (ultraviolet, visible, infrared and radio spectral regions), and his experimental attempts (jointly with F. A. Butaeva) to observe light amplification in gas discharge (paper submission of December 1957).
Extending the School Day or School Year
Authors: Patall Erika A. , Cooper Harris , Allen Ashley Batts
Published: September 2010

Attention has been directed toward extended school time as a measure to improve academic achievement. The school year and day length have varied over time and across localities depending on the particular needs of the community. Proponents argue that extending time will have learning and nonacademic benefits. Opponents suggest increased time is not guaranteed to lead to more effective instruction and suggest other costs. Despite noted limitations in the research, past reviewers have argued that any positive relation between allocated time and achievement is tentative and instructional quality needs to be addressed first. After a comprehensive search of the literature, 15 empirical studies of various designs conducted since 1985 were found. The literature revealed that (a) designs are generally weak for making causal inferences and (b) outcomes other than achievement are scarcely studied. That said, findings suggest that extending school time can be an effective way to support student learning, particularly (a) for students most at risk of school failure and (b) when considerations are made for how time is used. Of note, the strongest research designs produced the most consistent positive results. Implications for policy and practice are discussed.
The Effects of Vocabulary Intervention on Young Children’s Word Learning
Authors: Marulis Loren M. , Neuman Susan B.
Published: September 2010

This meta-analysis examines the effects of vocabulary interventions on pre-K and kindergarten children’s oral language development. The authors quantitatively reviewed 67 studies and 216 effect sizes to better understand the impact of training on word learning. Results indicated an overall effect size of .88, demonstrating, on average, a gain of nearly one standard deviation on vocabulary measures. Moderator analyses reported greater effects for trained adults in providing the treatment, combined pedagogical strategies that included explicit and implicit instruction, and author-created measures compared to standardized measures. Middle- and upper-income at-risk children were significantly more likely to benefit from vocabulary intervention than those students also at risk and poor. These results indicate that although they might improve oral language skills, vocabulary interventions are not sufficiently powerful to close the gap—even in the preschool and kindergarten years.
Prevalence and Risk Factors of Hypertension Among School Going Children of Dhaka City
Authors: Rahman AFM Mizanur , Afroze Ainun , Islam MN
Published: September 2010

Despite general belief that hypertension is a disease of adulthood, children and adolescents can also suffer from the condition and may remain unnoticed because of lack of routine measurement of blood pressure. Hypertension in children in Bangladesh has not been well studied. Hence a study was conducted among 6-16 year-old school children of Dhaka city to find out the pattern of blood pressure (BP), prevalence of hypertension and its risk factors in this age group.In this cross sectional study, 1995 apparently healthy children of specified age group were systematically sampled from 6 purposively selected schools in Dhaka city. Their BP were measured methodically under ideal situation. On the same day, their anthropometry were also done by taking height and weight. All of them were given a questionnaire to take home for filling up the family history of hypertension, education, occupation and monthly income of their parents. Those who had BP above 95th centile on three occasions with an interval of two weeks, were diagnosed as hypertensive.Among the 1995 children, male female ratio was 1:1. There were 127-238 children in each single-year age category. Most of their fathers were service holders with 10-14 years of education. Mean systolic BP (SBP) ranged from 88.6 to 113.5 mm Hg, and mean diastolic BP (DBP) from 55.3 to 74.2 mm Hg. Girls had both SBP and DBP more than boys of same age category.Both SBP and DPB have linear relationship with age. There was significant increment in both the systolic and diastolic BP among the female children from 9 to 10 years of age. Similar sudden increment of only systolic blood pressure was seen from 13 to 14 year old male children.This study showed that prevalence of hypertension in school going children of Dhaka city was 0.55% and there was a significant relationship of hypertension with the obesity and family history of hypertension. Among the 11 hypertensive children, 9 (81.8%) had either of the two risk factors, odds ratio (95% CI) being 15.37 (3.31 - 71.37). Key words: Hypertension; school going children. DOI: 10.3329/bjch.v29i3.6184 Bangladesh J Child Health 2005; Vol 29 (3): 82-87
Incidence of Congenital Hypothyroidism in the Newborn of A Tertiary Hospital in Southern Bangladesh
Authors: Rasul CH , Lucky SN , Miah SR , Moslem F
Published: September 2010

Background: Congenital hypothyroidism is the commonest preventable cause of mental retardation. It is more prevalent in endemic goiter regions like Bangladesh. But magnitude of the problem has not been studied at national level.Objective: To detect the incidence of congenital hypothyroidism among the newborn delivered in Khulna Medical College Hospital in southern part of Bangladesh and to rationalize the development of neonatal screening program.Methodology: All the living newborns delivered between Oct '01 to June ‘05 in Khulna Medical College Hospital were included in the study. After taking the relevant information from mother, cord blood sample were collected from the newborn within 24 hours of birth and kept in freezer. At the end of collection of each two month, the lot of blood sample was sent to the laboratory of Institute of Nuclear Medicine, Dhaka for radioimmunoassay of TSH. Potential cases with TSH value above 10 MIU/L were recalled for thyroid function test for confirmation of diagnosis.Results: After discarding unsatisfactory samples, 1353 samples were assayed for TSH. Among the study population 88.2% hailed from Khulna district and the rest of the cases came from neighboring districts. Male to female ratio was 1.2:1. Regarding the birth weight 33.4% babies were of low birth weight. TSH above 10 MIU/L were found in 35 babies among whom one baby was hypothyroid and the other member of the twin was also hypothyroid although the TSH level was below 10 MIU/L. Thus incidence of congenital hypothyroidism was 1.5 per thousand living newborn among the studied cases.Conclusion: The incidence of congenital hypothyroidism in southern part of the country is quite high in relation to global incidence. Although this is not the national picture but the high figure is alarming. So, neonatal screening program should be implemented as soon as possible to find out the real case burden in the community and thereby to take care of them and reduce the number of mentally retarded children in our country. Key words: Congenital hypothyroidism; neonatal screening; mental retardation. DOI: 10.3329/bjch.v29i3.6186 Bangladesh J Child Health 2005; Vol 29 (3): 88-92
Future Trends in the Pharmacogenomics of Brain Disorders and Dementia: Influence of APOE and CYP2D6 Variants
Authors: Cacabelos Ramón , Fernández-Novoa Lucía , Martínez-Bouza Rocío , McKay Adam , Carril Juan C. , Lombardi Valter , Corzo Lola , Carrera Iván , Tellado Iván , Nebril Laura , Alcaraz Margarita , Rodríguez Susana , Casas Ángela , Couceiro Verónica , Álvarez Antón
Published: September 2010

About 80% of functional genes in the human genome are expressed in the brain and over 1,200 different genes have been associated with the pathogenesis of CNS disorders and dementia. Pharmacogenetic studies of psychotropic drug response have focused on determining the relationship between variations in specific candidate genes and the positive and adverse effects of drug treatment. Approximately, 18% of neuroleptics are substrates of CYP1A2 enzymes, 40% of CYP2D6, and 23% of CYP3A4; 24% of antidepressants are substrates of CYP1A2 enzymes, 5% of CYP2B6, 38% of CYP2C19, 85% of CYP2D6, and 38% of CYP3A4; 7% of benzodiazepines are substrates of CYP2C19 enzymes, 20% of CYP2D6, and 95% of CYP3A4. 10-20% of Western populations are defective in genes of the CYP superfamily; and the pharmacogenomic response of psychotropic drugs also depends on genetic variants associated with dementia. Prospective studies with anti-dementia drugs or with multifactorial strategies have revealed that the therapeutic response to conventional drugs in Alzheimer’s disease is genotype-specific. The disease-modifying effects (cognitive performance, biomarker modification) of therapeutic intervention are APOE-dependent, with APOE-4 carriers acting as the worst responders (APOE-3/3 > APOE-3/4 > APOE-4/4). APOE-CYP2D6 interactions also influence the therapeutic outcome in patients with dementia.
ZERO: Probabilistic Routing for Deploy and Forget Wireless Sensor Networks
Authors: Vilajosana Xavier , Llosa Jordi , Pacho Jose Carlos , Vilajosana Ignasi , Juan Angel A. , Vicario Jose Lopez , Morell Antoni
Published: September 2010

As Wireless Sensor Networks are being adopted by industry and agriculture for large-scale and unattended deployments, the need for reliable and energy-conservative protocols become critical. Physical and Link layer efforts for energy conservation are not mostly considered by routing protocols that put their efforts on maintaining reliability and throughput. Gradient-based routing protocols route data through most reliable links aiming to ensure 99% packet delivery. However, they suffer from the so-called ”hot spot” problem. Most reliable routes waste their energy fast, thus partitioning the network and reducing the area monitored. To cope with this ”hot spot” problem we propose ZERO a combined approach at Network and Link layers to increase network lifespan while conserving reliability levels by means of probabilistic load balancing techniques.
A Smart Checkpointing Scheme for Improving the Reliability of Clustering Routing Protocols
Authors: Min Hong , Jung Jinman , Kim Bongjae , Cho Yookun , Heo Junyoung , Yi Sangho , Hong Jiman
Published: September 2010

In wireless sensor networks, system architectures and applications are designed to consider both resource constraints and scalability, because such networks are composed of numerous sensor nodes with various sensors and actuators, small memories, low-power microprocessors, radio modules, and batteries. Clustering routing protocols based on data aggregation schemes aimed at minimizing packet numbers have been proposed to meet these requirements. In clustering routing protocols, the cluster head plays an important role. The cluster head collects data from its member nodes and aggregates the collected data. To improve reliability and reduce recovery latency, we propose a checkpointing scheme for the cluster head. In the proposed scheme, backup nodes monitor and checkpoint the current state of the cluster head periodically. We also derive the checkpointing interval that maximizes reliability while using the same amount of energy consumed by clustering routing protocols that operate without checkpointing. Experimental comparisons with existing non-checkpointing schemes show that our scheme reduces both energy consumption and recovery latency.