bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Novel Molecular Tweezers based on 3,6-O-(2-acylhydrazinocarbonyl) Esters of Hyodeoxycholic acid using Microwave Irradiation
Authors: Li Xiaorui , Qiu Liying , Mei Qinggang , Bi Qingwei , Zhao Zhigang
Published: July 2011

Ten novel molecular tweezers based on the 3,6- O-(2-acylhydrazinocarbonyl) esters of hyodeoxycholic acid have been synthesised using microwave irradiation. Their structures were established by 1H NMR, IR, MS spectra and elemental analysis. Their binding properties were examined by UV-Vis spectra titration. The preliminary results indicate that these molecular tweezers show good recognition properties for Cl-, Br-, I-.
Synthesis and Anticoccidial Activities of Substituted Ethyl 4-Hydroxy-11-Oxo-11H-Chromeno[2,3-g]Quinoline-3-Carboxylates
Authors: Wang Zhi , Zhou Li-juan , Wang Yu-liang , Weng Ya-biao , He Jun , Nie Kui
Published: July 2011

A series of substituted ethyl 4-hydroxy-11-oxo-11 H-chromeno[2,3-g]quinoline-3-carboxylates were designed and synthesised as anticoccidial drugs, and the structures were characterised by 1H NMR, MS, IR spectra and elementary analysis. The anticocciadial activities of the new compounds were assessed according to the anticoccidial index method. The results demonstrated that four of these compounds exihibited effective anticoccidial activities against Eimeria tenella in chicken's diet with a dose of 27 mg kg−1.
Detouring the Undesired Route of Helicobacter pylori-Induced Gastric Carcinogenesis
Authors: Kim Eun-Hee , Hong Kyung-Sook , Hong Hua , Hahm Ki Baik
Published: July 2011

Epidemiological and experimental evidence has emerged that a dysregulated inflammation is associated with most of the tumors, and many studies have begun to unravel the molecular pathways linking inflammation and cancer. As a typical example linking these associations, Helicobacter pylori (H. pylori) infection-associated atrophic gastritis has been recognized as precursor lesion of gastric cancer. The identification of transcription factors such as NF-κB and STAT3, and their gene products such as IL-8, COX-2, iNOS, cytokines, chemokines and their receptors, etc have laid the molecular foundation for our understanding of the decisive role of inflammation in carcinogenesis. In addition to the role as the initiator of cancer, inflammation contributes to survival and proliferation of malignant cells, tumor angiogenesis, and even metastasis. In this review, the fundamental mechanisms of H. pylori-induced carcinogenesis as well as the possibility of cancer prevention through suppressing H. pylori-induced inflammation are introduced. We infer that targeting inflammatory pathways have a potential role to detour the unpleasant journey to H. pylori-associated gastric carcinogenesis.
A Choice Prediction Competition for Social Preferences in Simple Extensive Form Games: An Introduction
Authors: Ert Eyal , Erev Ido , Roth Alvin E.
Published: July 2011

Two independent, but related, choice prediction competitions are organized that focus on behavior in simple two-person extensive form games (http://sites.google.com/site/extformpredcomp/): one focuses on predicting the choices of the first mover and the other on predicting the choices of the second mover. The competitions are based on an estimation experiment and a competition experiment. The two experiments use the same methods and subject pool, and examine games randomly selected from the same distribution. The current introductory paper presents the results of the estimation experiment, and clarifies the descriptive value of some baseline models. The best baseline model assumes that each choice is made based on one of several rules. The rules include: rational choice, level-1 reasoning, an attempt to maximize joint payoff, and an attempt to increase fairness. The probability of using the different rules is assumed to be stable over games. The estimated parameters imply that the most popular rule is rational choice; it is used in about half the cases. To participate in the competitions, researchers are asked to email the organizers models (implemented in computer programs) that read the incentive structure as input, and derive the predicted behavior as an output. The submission deadline is 1 December 2011, the results of the competition experiment will not be revealed until that date. The submitted models will be ranked based on their prediction error. The winners of the competitions will be invited to write a paper that describes their model.
N-[1-(1H-Benzimidazol-2-yl)-2-(5-chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)vinyl]benzamide
Authors: Kaushik Darpan , Maan Namita
Published: July 2011

A novel benzimidazole derivative (2) was synthesized by hydrolyzing 4-[(5-chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)methylene]-2-phenyloxazol-5(4H)-one (1), the azlactone precursor in an acidic medium and treating the product with o-phenylenediamine (OPDA) in situ. The structure of the title compound (2) was established on basis of FT-IR, 1H-NMR, 13C-NMR and mass spectral data.
Preliminary Phytochemical Screening and In Vitro Anti-Helicobacter pylori Activity of Extracts of the Stem Bark of Bridelia micrantha (Hochst., Baill., Euphorbiaceae)
Authors: Okeleye Benjamin I. , Bessong Pascal O. , Ndip Roland N.
Published: July 2011

Helicobacter pylori is a major risk factor for gastritis, ulcers and gastric cancer. This study was aimed to determine the antimicrobial activity of the stem bark of Bridelia. micrantha on H. pylori isolated in South Africa. Extracts and clarithromycin were tested against 31 clinical strains, including a standard strain (NCTC 11638) of H. pylori, by measuring the diameters of the corresponding inhibition zones, followed by determination of the Minimum Inhibitory Concentration (MIC) (using metronidazole, and amoxicillin as control antibiotics) and the rate of kill. Preliminary phytochemical screening was also done. Inhibition zone diameters which ranged from 0–23 mm were observed for all five of the extracts and 0–35 mm for clarithromycin. Marked susceptibility of strains (100%) was noted for the acetone extract (P < 0.05), followed by ethyl acetate extract (93.5%). The MIC50 values ranged from 0.0048 to 0.156 mg/mL for the ethyl acetate extract and 0.0048 to 0.313 mg/mL for the acetone extract. The MIC90 values ranged from 0.0048 to 2.5 mg/mL for the ethyl acetate extract and 0.078 to >0.625 mg/mL for the acetone extract, respectively. Insignificant statistical difference in potency was observed when comparing the crude ethyl acetate extract to metronidazole and amoxicillin (P > 0.05). Complete killing of strain PE430C by the ethyl acetate extract was observed at 0.1 mg/mL (2 × MIC) and 0.2 mg/mL (4 × MIC) at 66 and 72 h. For strain PE369C, 100% killing was observed at 0.1 mg/mL (2 × MIC) in 66 and 72 h. The ethyl acetate extract could thus be a potential source of lead molecules for the design of new anti-Helicobacter pylori therapies as this study further confirmed the presence of phytochemicals including alkaloids, flavonoids, steroids, tannins and saponins.
Antiradical, Chelating and Antioxidant Activities of Hydroxamic Acids and Hydroxyureas
Authors: Končić Marijana Zovko , Barbarić Monika , Perković Ivana , Zorc Branka
Published: July 2011

Reactive oxygen species, along with reactive nitrogen species, may play an important role in the pathogenesis and progress of many diseases, including cancer, diabetes and sickle cell disease. It has been postulated that hydroxyurea, one of the main treatments in sickle cell disease, achieves its activity partly also through its antioxidant properties. A series of hydroxyurea derivatives of L- and D-amino acid amides and cycloalkyl-N-aryl-hydroxamic acids was synthesized and investigated for their radical scavenging activity, chelating properties and antioxidant activity. All the compounds showed exceptional antiradical activities. For example, free radical scavenging activities of investigated hydroxyureas were higher than the activity of standard antioxidant, butylated hydroxyanisole (BHA). Moreover, most of the investigated hydroxamic acids were stronger Fe2+ ion chelators than quercetin. In addition, the investigated compounds, especially hydroxamic acids, were proven to be excellent antioxidants. They were as effective as BHA in inhibiting b-carotene-linoleic acid coupled oxidation. It is reasonable to assume that the antioxidant activity of the investigated compounds could contribute to their previously proven biological properties as cytostatic and antiviral agents.
The Inhibitory Potential of Thai Mango Seed Kernel Extract against Methicillin-Resistant Staphylococcus Aureus
Authors: Jiamboonsri Pimsumon , Pithayanukul Pimolpan , Bavovada Rapepol , Chomnawang Mullika T.
Published: July 2011

Plant extracts are a valuable source of novel antibacterial compounds to combat pathogenic isolates of methicillin-resistant Staphylococcus aureus (MRSA), a global nosocomial infection. In this study, the alcoholic extract from Thai mango (Mangifera indica L. cv. ‘Fahlun’) seed kernel extract (MSKE) and its phenolic principles (gallic acid, methyl gallate and pentagalloylglucopyranose) demonstrated potent in vitro antibacterial activity against Staphylococcus aureus and 19 clinical MRSA isolates in studies of disc diffusion, broth microdilution and time-kill assays. Electron microscopy studies using scanning electron microscopy and transmission electron microscopy revealed impaired cell division and ultra-structural changes in bacterial cell morphology, including the thickening of cell walls, of microorganisms treated with MSKE; these damaging effects were increased with increasing concentrations of MSKE. MSKE and its phenolic principles enhanced and intensified the antibacterial activity of penicillin G against 19 clinical MRSA isolates by lowering the minimum inhibitory concentration by at least 5-fold. The major phenolic principle, pentagalloylglucopyranose, was demonstrated to be the major contributor to the antibacterial activity of MSKE. These results suggest that MSKE may potentially be useful as an alternative therapeutic agent or an adjunctive therapy along with penicillin G in the treatment of MRSA infections.
A Novel Systematic Error Compensation Algorithm Based on Least Squares Support Vector Regression for Star Sensor Image Centroid Estimation
Authors: Yang Jun , Liang Bin , Zhang Tao , Song Jingyan
Published: July 2011

The star centroid estimation is the most important operation, which directly affects the precision of attitude determination for star sensors. This paper presents a theoretical study of the systematic error introduced by the star centroid estimation algorithm. The systematic error is analyzed through a frequency domain approach and numerical simulations. It is shown that the systematic error consists of the approximation error and truncation error which resulted from the discretization approximation and sampling window limitations, respectively. A criterion for choosing the size of the sampling window to reduce the truncation error is given in this paper. The systematic error can be evaluated as a function of the actual star centroid positions under different Gaussian widths of star intensity distribution. In order to eliminate the systematic error, a novel compensation algorithm based on the least squares support vector regression (LSSVR) with Radial Basis Function (RBF) kernel is proposed. Simulation results show that when the compensation algorithm is applied to the 5-pixel star sampling window, the accuracy of star centroid estimation is improved from 0.06 to 6 × 10−5 pixels.
An Efficient Direction Field-Based Method for the Detection of Fasteners on High-Speed Railways
Authors: Yang Jinfeng , Tao Wei , Liu Manhua , Zhang Yongjie , Zhang Haibo , Zhao Hui
Published: July 2011

Railway inspection is an important task in railway maintenance to ensure safety. The fastener is a major part of the railway which fastens the tracks to the ground. The current article presents an efficient method to detect fasteners on the basis of image processing and pattern recognition techniques, which can be used to detect the absence of fasteners on the corresponding track in high-speed(up to 400 km/h). The Direction Field is extracted as the feature descriptor for recognition. In addition, the appropriate weight coefficient matrix is presented for robust and rapid matching in a complex environment. Experimental results are presented to show that the proposed method is computation efficient and robust for the detection of fasteners in a complex environment. Through the practical device fixed on the track inspection train, enough fastener samples are obtained, and the feasibility of the method is verified at 400 km/h.
Smart Roadside System for Driver Assistance and Safety Warnings: Framework and Applications
Authors: Jang Jeong Ah , Kim Hyun Suk , Cho Han Byeog
Published: July 2011

The use of newly emerging sensor technologies in traditional roadway systems can provide real-time traffic services to drivers through Telematics and Intelligent Transport Systems (ITSs). This paper introduces a smart roadside system that utilizes various sensors for driver assistance and traffic safety warnings. This paper shows two road application models for a smart roadside system and sensors: a red-light violation warning system for signalized intersections, and a speed advisory system for highways. Evaluation results for the two services are then shown using a micro-simulation method. In the given real-time applications for drivers, the framework and certain algorithms produce a very efficient solution with respect to the roadway type features and sensor type use.
Dive Market Segments and Destination Competitiveness: A Case Study of the Great Barrier Reef in View of Changing Reef Ecosystem Health
Authors: Pabel Anja , Coghlan Alexandra
Published: July 2011

Understanding certified divers' perceptions of their Great Barrier Reef (GBR) experience is important to ensure a high-quality dive tourism product. The study examined what dive trip attributes were important to divers and how different dive markets perceived the GBR's environmental
quality. The study borrows elements from the recreational specialization literature to explore differences in perceptions of the GBR between dive market segments. Results reveal that the more experienced “enthusiast” divers compared the GBR less favorably with regards to its environmental
attributes, while “learners” were more favorable in their comparisons but also more concerned with the cost of their trip. The results suggest we consider marketing implications of changes in reef quality in light of a highly heterogeneous dive market.
Low Molecular Weight Opioid Peptide Esters Could be Developed as a New Class of Analgesics
Authors: Goldberg Joel S.
Published: July 2011

Low molecular weight opioid peptide esters (OPE) could become a class of analgesics with different side effect profiles than current opiates. OPE may have sufficient plasma stability to cross the blood brain barrier (BBB), undergo ester hydrolysis and produce analgesia. OPE of dipeptides, tyr-pro and tyr-gly conjugated to ethanol have a structure similar to the anesthestic agent, etomidate. Based upon the analgesic activity of dipeptide opioids, Lipinski's criteria, and permeability of select GABA esters to cross the BBB, opioid peptides (OP) conjugated to ethanol, cholesterol or 3-glucose are lead recommendations. Preliminary animal data suggests that tyr-pro-ethyl ester crosses the BBB and unexpectedly produces hyperalgesia. Currently, there are no approved OP analgesics available for clinical use. Clinical trials of good manufacturing practice OP administered to patients suffering from chronic pain with indwelling intrathecal pumps could resolve the issue that OP may be superior to opiates and may redirect research.
Évaluation à moyen terme des besoins en engrais minéraux (N, P, K) d'une rotation en grandes cultures sur sol argileux
Authors: Tremblay G. J. , Boisvert J. , Fréchette G. É. , Saulnier M. , Alexandre R. , Vanasse A.
Published: July 2011

Tremblay, G. J., Boisvert, J., Fréchette, G. É., Saulnier, M., Alexandre, R. and Vanasse, A. 2011. Mid term evaluation of mineral fertilizer requirements (N, P, K) of a field crop rotation on a clay soil. Can. J. Soil Sci. 91: 637–646. In Quebec, the recommended fertilizer requirements have been lowered since 1994. A study was undertaken from 1998 to 2005 in a 4-yr rotation of wheat (Triticum aestivum L.), soybean [Glycine max (L.) Merr.] and grain corn (Zea mays L.) to verify the mid-term mineral fertilizer requirements (N, P, K) for these field crops. Four levels of nitrogen (N) and three levels of phosphorus (P) and potassium (K) were compared on a clay soil of the Saint-Lawrence Lowlands. Nitrogen requirements based on this study corresponded to the recommended levels of each field crop tested. Recommended phosphorus rates did not maintain initial PM-III soil level (1998). However, crop yields were not affected by this decrease in soil PM-III level. To improve fertilizer recommendation tables, it should be relevant to determine with more accuracy the critical phosphorus and potassium values for field crops on other typical Quebec soils.
Estimating trembling aspen productivity in the boreal transition ecoregion of Saskatchewan using site and soil variables
Authors: Pinno Bradley , Bélanger Nicolas
Published: July 2011

Pinno, B. D. and Bélanger, N. 2011. Estimating trembling aspen productivity in the boreal transition ecoregion of Saskatchewan using site and soil variables. Can. J. Soil Sci. 91: 661–669. The productivity of trembling aspen, as expressed by site quality index (SQI), in natural stands growing on three different soil parent material types (fluvial, lacustrine and glacial till) in the boreal transition ecoregion of Saskatchewan was evaluated by using soil and site variables. The soil and site variables used were either general categorical variables, such as parent material and ecosite, or continuous variables, such as soil texture (percent sand or clay), pH, carbon, nitrogen, C:N ratios, and elemental composition. It was not possible to reliably estimate SQI using only categorical site variables or continuous soil variables when all plots were grouped together. However, when plots were grouped by parent material type, over 45% of the variability in trembling aspen productivity was explained using the common soil measurements of texture and pH. In estimating SQI, there was an interaction between both pH and soil texture with parent material. On fluvial and lacustrine parent materials, increased clay content was positively correlated with SQI, but was negatively correlated with SQI on till, while pH was positively correlated with SQI on fluvial parent material, but negatively on lacustrine. Including more sophisticated measures of soil nutrient availability in the forest floor and BC horizons did not improve the SQI prediction. This study indicates that it is possible to estimate trembling aspen productivity using simple site and soil variables, provided that differences in soil properties within parent material groupings are considered in the analysis.
Comparing and evaluating digital soil mapping methods in a Hungarian forest reserve
Authors: Illés Gábor , Kovács Gábor , Heil Bálint
Published: July 2011

Illés, G., Kovács, G. and Heil, B. 2011. Comparing and evaluating digital soil mapping methods in a Hungarian forest reserve. Can. J. Soil Sci. 91: 615–626. To investigate applications of widespread digital soil mapping methods in forestry management, soil maps for a Hungarian forest reserve were developed using general discriminant and classification tree analysis as predictive tools. Soil samples were collected applying an unaligned semi-systematic grid. Second level units of the World Reference Base of Soil Resources and their yield capacity were determined. Terrain attributes were derived using a digital elevation model, and they were assigned to soil data to be used as predictors for second level units of the World Reference Base for Soil Resources (SLU) maps. A comparison was made of prediction accuracy. Both the discriminant analysis and the classification tree-based prediction were able to derive SLU maps; however, the classification accuracies were uneven. The methods used provided 63–65% average classification accuracy for dominant SLUs, but only 0–18% in the case of less common SLUs. One of the major issues of digital soil mapping that needs to be addressed is that the same inputs may result in different output maps depending on the use of spatial predictions. To overcome this problem we created a new combination of these methods in which the classification accuracies were used to select the most appropriate prediction. For each location, the method that gave higher prediction accuracy was used to extend the soil map to unknown areas. In this way we improved the overall accuracy of output maps as well as the prediction accuracies of individual SLUs.
Development and evaluation of a new Canadian spring wheat sub-model for DNDC
Authors: Kröbel R. , Smith W. , Grant B. , Desjardins R. , Campbell C. , Tremblay N. , Li C. , Zentner R. , McConkey B.
Published: July 2011

Kröbel, R., Smith, W. N., Grant, B. B., Desjardins, R. L., Campbell, C. A., Tremblay, N., Li, C. S., Zentner, R. P. and McConkey, B. G. 2011. Development and evaluation of a new Canadian spring wheat sub-model for DNDC. Can. J. Soil Sci. 91: 503–520. In this paper, the ability of the DNDC model (version 93) to predict biomass production, grain yield and plant nitrogen content was assessed using data from experiments at Swift Current, Saskatchewan, and St-Blaise, Quebec, Canada. While predicting wheat grain yields reasonably well, the model overestimated the growth of above-ground plant biomass and nitrogen uptake during the first half of the growing season. A new spring wheat sub-model (DNDC-CSW) was introduced with a modified plant biomass growth curve, dynamic plant C/N ratios and modified plant biomass fractioning curves. DNDC-CSW performed considerably better in simulating plant biomass [modeling efficiency (EF): 0.75, average relative error (ARE): 6.0%] and plant nitrogen content (EF: 0.61, ARE: −2.7%) at Swift Current and St-Blaise (EF of 0.75 and ARE of 2.3%), compared with DNDC 93 (biomass SC: EF 0.49, ARE 17.1%, SB: EF 0.02 ARE 33.4%). In comparison with DNDC 93, DNDC-CSW better captured inter-annual variations in crop growth for a range of wheat rotations, increasing the EF from 0.32 to 0.52 for grain and from 0.35 to 0.39 for straw yields. DNDC-CSW also performed considerably better than DNDC 93 in estimating soil carbon changes at Swift Current. Hence, DNDC-CSW has the potential to improve the performance of DNDC 93 in simulating wheat biomass, plant nitrogen, yield and soil carbon at various Canadian sites.
Minería de textos: la nueva generación de análisis de literatura científica en biología molecular y genómica
Authors: Gálvez Carmen
Published: July 2011

Una vez descifrado la secuencia del genoma humano, el paradigma de investigación ha cambiado dando paso a la descripción de las funciones de los genes y a futuros avances en la lucha contra enfermedades. Este nuevo contexto ha despertado el interés de la Bioinformática, que combina métodos de las Ciencias de la Vida con las Ciencias de la Información haciendo posible el acceso a la gran cantidad de información biológica almacenada en las bases de datos, y de la Genómica, dedicada al estudio de las interacciones de los genes y su influencia en el desarrollo de enfermedades. En este contexto, la minería de textos surge como un instrumento emergente para el análisis de la literatura científica. Una tarea habitual de la minería de textos en Biología Molecular y Genómica es el reconocimiento de entidades biológicas, tales como genes, proteínas y enfermedades. El paso siguiente en el proceso de minería lo constituye la identificación entre entidades biológicas, tales como el tipo de interacción entre gen-gen, gen-enfermedad, gen-proteína, para interpretar funciones biológicas, o formular hipótesis de investigación. El objetivo de este trabajo es examinar el auge y las limitaciones la nueva generación de herramientas de análisis de la información en lenguaje natural, almacenada en bases de datos bibliográficas, como PubMed o MEDLINE.
Redes virtuais de aprendizagem na sociedade e na pesquisa
Authors: Freire Gustavo Henrique de Araújo
Published: July 2011

Apresenta um dos aspectos da tese de que uma rede virtual de aprendizagem (aqui denominada estoques de informação em fluxo) facilita a comunicação da informação nos grupos de usuários que dela participa. Aponta que a principal característica da sociedade contemporânea é a aplicação da informação e do conhecimento em um ciclo de realimentação cumulativo da inovação tecnológica. Discute o valor do capital intelectual para o processo de produção social, o que vem a exigir a constante atualização dos estoques dinâmicos de informação armazenados nos indivíduos. Define o papel dos profissionais da informação a partir da responsabilidade social de facilitar a comunicação da informação para um usuário que dela necessita, no processo de construção do seu próprio conhecimento. Propõe que as redes de aprendizagem assumam o papel fundamental de meio não somente na comunicação da informação, mas, especialmente, na criação de possibilidades de produção de novos conhecimentos.
Formação profissional do bibliotecário
Authors: Walter Maria Tereza Machado Teles , Baptista Sofia Galvão
Published: July 2011

A formação profissional de qualquer categoria profissional envolve aspectos variáveis que incluem questões sobre ética, empregabilidade, conceitos de trabalho, de profissão e de emprego. No caso específico dos bibliotecários, esses pontos são debatidos à luz da literatura, inserindo questões acerca do que seja a competência e de quais são aquelas mais ressaltadas pelos autores que tratam do tema, quando elaboram suas listas para evidenciar a necessidade de atenção dos profissionais que pretendem ser reconhecidos como modernos profissionais da informação. A tarefa de elaborar currículos que preencham todos os requisitos definidos é bastante complexa. Além disso, é inevitável a ênfase nas questões relacionadas às tecnologias de informação e de comunicação, cuja importância no trabalho dos bibliotecários é cada vez maior, seu uso mais intenso e determinante para aqueles que querem desenvolver produtos e serviços de informação cada vez mais adequados aos seus clientes.
Práticas de organização e divulgação da produção intelectual em Ciência da Informação no Brasil
Authors: Bufrem Leilah Santiago
Published: July 2011

Análise de questões teóricas sobre a construção de bases de dados, fundamentando-se em realizações práticas que vêm sendo desenvolvidas na constituição de uma fonte de informação, a base de dados BRAPCI. Discutem-se antinomias ou oposições entre o formalizado e o praticado, adotando-se como pressuposto a necessidade de crítica e autocrítica à prática e refletindo sobre a diferenciação entre os chamados indicadores quantitativos, aferíveis com a utilização de quantidades, medidas e números e os qualitativos, relacionados com qualidades avaliadas com a intermediação de construtos. Recomenda-se a complementaridade entre esses dois aspectos, quando da implementação de processos de avaliação de bases de dados.
Organização da informação e bibliometria
Authors: Café Ligia Maria Arruda , Bräscher Marisa
Published: July 2011

Padrões de organização da informação são necessários em pesquisas bibliométricas para que documentos que possuam características similares possam ser recolhidos em fontes primárias e secundárias e para que se possa atingir confiabilidade na análise dos dados. Com o objetivo de identificar as dificuldades encontradas por pesquisadores quanto aos aspectos de organização da informação, efetuou-se um levantamento de 59 relatos de teses e dissertações e realizaram-se entrevistas com especialistas da área. Conclui-se que, de maneira geral, as dificuldades se concentram principalmente na padronização de títulos de periódicos e de nomes de autor (descrição física), assim como na diversidade de representações de assunto (descrição de conteúdo). A necessidade de controle da literatura por meio da manutenção de bases de dados atualizadas é apontada pelos especialistas entrevistados como uma das principais dificuldades encontradas na realização de pesquisas na área de bibliometria no Brasil.
Long-term stability of TES satellite radiance measurements
Authors: Connor T. C. , Shephard M. W. , Payne V. H. , Cady-Pereira K. E. , Kulawik S. S. , Luo M. , Osterman G. , Lampel M.
Published: July 2011

Abstract. The utilization of Tropospheric Emission Spectrometer (TES) Level 2 (L2) retrieval products for the purpose of assessing long term changes in atmospheric trace gas composition requires knowledge of the overall radiometric stability of the Level 1B (L1B) radiances. The purpose of this study is to evaluate the stability of the radiometric calibration of the TES instrument by analyzing the difference between measured and calculated brightness temperatures in selected window regions of the spectrum. The Global Modeling and Assimilation Office (GMAO) profiles for temperature and water vapor and the Real-Time Global Sea Surface Temperature (RTGSST) are used as input to the Optimal Spectral Sampling (OSS) radiative transfer model to calculate the simulated spectra. The TES reference measurements selected cover a 4-year period of time from mid 2005 through mid 2009 with the selection criteria being; observation latitudes greater than −30° and less than 30°, over ocean, Global Survey mode (nadir view) and retrieved cloud optical depth of less than or equal to 0.01. The TES cloud optical depth retrievals are used only for screening purposes and no effects of clouds on the radiances are included in the forward model. This initial screening results in over 55 000 potential reference spectra spanning the four year period. Presented is a trend analysis of the time series of the residuals (observation minus calculations) in the TES 2B1, 1B2, 2A1, and 1A1 bands, with the standard deviation of the residuals being approximately equal to 0.6 K for bands 2B1, 1B2, 2A1, and 0.9 K for band 1A1. The analysis demonstrates that the trend in the residuals is not significantly different from zero over the 4-year period. This is one method used to demonstrate that the relative radiometric calibration is stable over time, which is very important for any longer term analysis of TES retrieved products (L2), particularly well-mixed species such as carbon dioxide and methane.
Multiplicative cascade models for fine spatial downscaling of rainfall: parameterization with rain gauge data
Authors: Rupp D. E. , Licznar P. , Adamowski W. , Leśniewski M.
Published: July 2011

Abstract. Capturing the spatial distribution of high-intensity rainfall over short-time intervals is critical for accurately assessing the efficacy of urban stormwater drainage systems. In a stochastic simulation framework, one method of generating realistic rainfall fields is by multiplicative random cascade (MRC) models. Estimation of MRC model parameters has typically relied on radar imagery or, less frequently, rainfall fields interpolated from dense rain gauge networks. However, such data are not always available. Furthermore, the literature is lacking estimation procedures for spatially incomplete datasets. Therefore, we proposed a simple method of calibrating an MRC model when only data from a moderately dense network of rain gauges are available, rather than from the full rainfall field. The number of gauges need only be sufficient to adequately estimate the variance in the ratio of the rain rate at the rain gauges to the areal average rain rate across the entire spatial domain. In our example for Warsaw, Poland, we used 25 gauges over an area of approximately 1600 km2. MRC models calibrated using the proposed method were used to downscale 15-min rainfall rates from a 20 by 20 km area to the scale of the rain gauge capture area. Frequency distributions of observed and simulated 15-min rainfall at the gauge scale were very similar. Moreover, the spatial covariance structure of rainfall rates, as characterized by the semivariogram, was reproduced after allowing the probability density of the random cascade generator to vary with spatial scale.
Complications of Tunneled Cuffed Hemodialysis Catheters in Patients with Human Immunodeficiency Virus Infection
Authors: Naoum Joseph J. , Weakley Sarah M. , Athamneh Husam , Kougias Panagiotis , Bechara Carlos F. , Lin Peter H.
Published: July 2011

Purpose

Although increased infectious and thrombotic complications have been reported in patients with human immunodeficiency virus (HIV), little is known regarding hemodialysis catheter-related complications in HIV patients. In this report, we reviewed our experience and complication rates for tunneled cuffed catheters (TCCs) in HIV patients requiring hemodialysis.

Methods

A total of 85 patients with HIV infection underwent TCC placement for hemodialysis between 1996 and 2009. Hospital records were reviewed to determine causes and risk factors for TCC-related complications in HIV patients. For comparison, we studied 85 age- and sex-matched low-risk HIV case controls who received TCC for hemodialysis during the same period.

Results

A total of 119 and 102 TCCs were inserted in the HIV and control group, respectively. Total numbers of catheter days in the HIV and control groups were 17,321 and 15,620 days, respectively. The primary unassisted TCC patency rates at 6 months in the HIV and control groups were 74% ± 11% and 86% ± 8%, respectively (NS). There was an increased TCC bacteremia rate in HIV patients compared with control subjects (5.38 vs. 2.66 per 1,000 TCC days, p=0.03). There was also a higher TCC tunnel infection rate in HIV patients compared with control cohorts (3.72 vs. 1.87 per 1,000 TCC days, p=0.04). Factors associated with increased catheter infection rate in HIV patients were 1) low CD4+ lymphocyte counts (<200/mm3), 2) low albumin level (<2.5 g/dl), and 3) history of illicit intravenous drug use.

Conclusion

TCCs are associated with an increased risk of infection in HIV patients requiring hemodialysis. Moreover, HIV infection is associated with an increased risk of mortality among hemodialysis patients. Hypoalbuminemia, history of intravenous drug use, and low CD4+ lymphocyte counts are associated with increased risk of catheter infection in HIV patients requiring hemodialysis.
Accuracy of Single-Step versus 2-Step Double-Mix Impression Technique
Authors: Franco Eduardo Batista , da Cunha Leonardo Fernandes , Herrera Francyle Simões , Benetti Ana Raquel
Published: July 2011

Objective. To investigate the accuracy of dies obtained from single-step and 2-step double-mix impressions. Material and Methods. Impressions (n=10) of a stainless steel die simulating a complete crown preparation were performed using a polyether (Impregum Soft Heavy and Light body) and a vinyl polysiloxane
(Perfectim Blue Velvet and Flexi-Velvet) in two consistencies, in one or two (without relief) steps. Accuracy of the stone dies was accessed at a measuring microscope, using a metallic
crown with perfect fit to the reference crown preparation. Data were submitted to 2-way ANOVA and Tukey test (α=0.05). Results. The single-step technique resulted in slightly larger dies, while the 2-step technique without relief produced significantly smaller dies, when compared to
the original stainless steel die. Stone dies obtained from 2-step polyether impressions were significantly smaller when compared to dies obtained from 2-step vinyl polysiloxane impressions (Impregum 2-step:
−290.94 ± 71.64 μm; Perfectim 2-step: −201.86 ± 28.58 μm). No significant differences were observed in dies obtained from either
polyether or vinyl polysiloxane with the single-step technique (Impregum single-step: 63.52 ± 16.60 μm; Perfectim single-step: 79.40 ± 14.11 μm).
Conclusion. Higher discrepancies were detected for the 2-step impression technique without relief for the investigated materials.
Temperature Dependence of the Activation Volume of Secondary Relaxation in Glass Formers
Authors: Sharifi Soheil
Published: July 2011

We study a nonmonotonic behavior with temperature of the activation volume ΔVβ of secondary relaxation in PPGE [Poly[(phenyl glycidyl ether)-co-formaldehyde]] and PVAc [Poly(vinyl acetate)] glass formers. Our results show that the non-monotonic behaviour of secondary relaxation does not depend on the type of the secondary relaxation. Moreover, the study of secondary relaxation under pressure at isothermal paths shows two different behaviours of ΔVβ in the glassy state (which describe two different types of glasses); for temperatures higher than the glass transition temperature (Tg), ΔVβ increases with a decrease of the temperature while at temperatures lower than Tg, ΔVβ decreases with a decrease of the temperature.
Phenytoin-Induced Gingival Overgrowth: A Review of the Molecular, Immune, and Inflammatory Features
Authors: Corrêa Jôice Dias , Queiroz-Junior Celso Martins , Costa José Eustáquio , Teixeira Antônio Lúcio , Silva Tarcilia Aparecida
Published: July 2011

Gingival overgrowth (GO) is a side effect associated with some distinct classes of drugs, such as anticonvulsants, immunosuppressant, and calcium channel blockers. GO is characterized by the accumulation of extracellular matrix in gingival connective tissues, particularly collagenous components, with varying degrees of inflammation. One of the main drugs associated with GO is the antiepileptic phenytoin, which affects gingival tissues by altering extracellular matrix metabolism. Nevertheless, the pathogenesis of such drug-induced GO remains fulfilled by some contradictory findings. This paper aims to present the most relevant studies regarding the molecular, immune, and inflammatory aspects of phenytoin-induced gingival overgrowth.
Unité Rhumatologique des Affections de la Main (URAM) scale: Development and validation of a tool to assess Dupuytren's disease–specific disability
Authors: Beaudreuil Johann , Allard Anne , Zerkak Djamila , Gerber Robert A. , Cappelleri Joseph C. , Quintero Nathaly , Lasbleiz Sandra , Bernabé Brigitte , Orcel Philippe , Bardin Thomas ,   URAM Study Group
Published: July 2011

Objective

To our knowledge, no functional outcome measure has been developed and validated for Dupuytren's disease. We aimed to develop and validate a patient‐reported functional outcome measure for Dupuytren's disease.

Methods

Patients with Dupuytren's disease (n = 9) and medical experts (n = 7) provided input and opinions about limiting activities that were difficult to perform because of Dupuytren's disease for item generation. The provisional scale was studied in an independent sample of patients (n = 85) for item reduction according to response distribution, reliability, redundancy, and loading in a 1‐factor solution. The final scale was evaluated as follows: reliability using Cronbach's alpha coefficient and test–retest intraclass correlation coefficient from the previous 85‐patient population, and construct validity and responsiveness after needle aponeurotomy in another independent 53‐patient sample. For construct validity, convergent validity and divergent validity were tested. The clinically important change was estimated relative to a 1‐point categorical change on the Tubiana scale.

Results

A 52‐item provisional scale was generated and reduced to the final 9‐item scale called the Unité Rhumatologique des Affections de la Main (URAM) scale (total score 0–45). The scale showed good to excellent reliability and suitable construct validity. The URAM score improved after needle aponeurotomy: the standardized effect size was 0.56. The estimated clinically important change of the URAM scale was 2.9 points.

Conclusion

We provide the first patient‐reported functional measure for Dupuytren's disease. The URAM scale demonstrated suitable psychometric properties, and is short and convenient enough for easy use in daily practice and in clinical studies.
Reducing prejudice in organizations: The role of intergroup contact, out‐group homogeneity, and in‐group size
Authors: Hee Florence , Finkelman Jay , Lopez Patricia Denise , Ensari Nurcan
Published: July 2011

This survey study investigated the direct and indirect relationships among intergroup contact, in‐group size, out‐group homogeneity, in‐group homogeneity, and prejudice. The participants were 299 White women from seven Catholic congregations in the United States. The survey results indicated that in‐group size was positively related to prejudice toward racial out‐group members. Intergroup contact also mediated the relationship between in‐group size and prejudice. Moreover, perceptions of out‐group homogeneity not only correlated positively with prejudice, but also mediated the relationship between quantity and quality of intergroup contact and prejudice. Finally, perceptions of in‐group homogeneity were positively associated with prejudice. These results not only demonstrate the value of the frequency and depth of intergroup contact on reducing prejudice, but also highlight the role of in‐group size in influencing opportunities for contact. Moreover, perceptions of heterogeneity/uniqueness of both in‐group and out‐group members appear to serve as mechanisms through which contact reduces prejudice.
Congruency between organizational service climate and personal values in Hong Kong
Authors: Cheng Kevin H. C. , Hui C. Harry , Wang Yongli
Published: July 2011

The present study examined employees' service quality as a function of person–organization fit in terms of value congruence. A multilevel analysis was conducted on data collected on 518 Chinese employees in five service organizations. The results supported that employees' perception of service climate interacted with personal value for service. When there was congruence between personal value and perceived service climate, even when both characteristics were low, service quality was still higher than when the service climate was incongruous with the employees' own personal value. The results could be found only at the individual level and did not extend to the group level, where employees' perception of service climate was aggregated.
The effects of trust‐ and leadership‐based practices in virtual alliance outcomes
Authors: Preston‐Ortiz Dina
Published: July 2011

Outsourcing increases supported by technology have led to the formation of virtual strategic partnerships. Historically, 70% to 75% of alliance partnerships fail because members are often competitors outside the alliance network. To address alliance failure, a Delphi study was conducted to identify the role of trust and alliance performance outcomes in the areas of contractual and management control, resource sharing, and network flexibility for the successful development of partnerships within the meeting and events industry. A three‐round Delphi study provided robust data that support the importance of trust in creating a platform of respect, increased partner cooperation, and understanding among stakeholders. The central finding of this Delphi study is that, in general, leadership‐based practices have a greater influence on virtual strategic‐alliance performance than trust‐based practices. Findings support a contingency approach to create a platform of respect, alliance vision, clear roles, and partner expectations to build trust. A majority of the expert panel included trust as a contributor to the collective performance of the alliance when alliance members work as a team to meet or exceed individual member's goals and net profit objectives. All expert panel responses to the six themes proposed on how trust among virtual strategic‐alliance members influences business operations and the performance of individual alliance members are presented in the study.
Fostering success through a sense of urgency: Organizational culture and change efforts
Authors: Heitner Keri L.
Published: July 2011

A Sense of Urgency

By John P. Kotter

Boston: Harvard Business Press, 2008. 196 pp. ISBN: 978‐1‐4221‐7971‐0. $22.00
The problems with whistle‐blowing: U.S. v. Wailly
Authors: Malmstrom Frederick V.
Published: July 2011

Whistle‐blowing is traditionally a dangerous, unequal activity that pits the individual against his or her own organization. The author examines the 1975 U.S. Air Force Academy embezzlement case of U.S. v. Wailly, including the reluctance of numerous parties who allegedly disregarded advance warnings about Major Louis F. Wailly's criminal activities, as well as the subsequent organizational fallout from the affair. Survey data from 2,600 service academy graduates from 1959 to 2010, and a Volunteer Contribution Mechanism (VCM) experiment with 72 cadets discount the conventional wisdom that whistle‐blowing and loyalty are necessarily moral tradeoffs. Whistle‐blowing as a model of the suboptimal Nash equilibrium is also examined.
Open source college textbooks: An introduction to a market disrupter
Authors: Aguiar Elizabeth
Published: July 2011

Higher education textbook publishing is a mature and highly consolidated industry where barriers to entry are high. The industry is currently transitioning from a print‐centric to a digital‐first model, and this transition provides fertile ground for disrupters, particularly those whose focus is on Open Source content.
Measuring the successes and deficiencies of constant pH molecular dynamics: A blind prediction study
Authors: Williams Sarah L. , Blachly Patrick G. , McCammon J. Andrew
Published: July 2011

A constant pH molecular dynamics method has been used in the blind prediction of pKa values of titratable residues in wild type and mutated structures of the Staphylococcal nuclease (SNase) protein. The predicted values have been subsequently compared to experimental values provided by the laboratory of García‐Moreno. CpHMD performs well in predicting the pKa of solvent‐exposed residues. For residues in the protein interior, the CpHMD method encounters some difficulties in reaching convergence and predicting the pKa values for residues having strong interactions with neighboring residues. These results show the need to accurately and sufficiently sample conformational space in order to obtain pKa values consistent with experimental results. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Attitudinal impact of hybridized writing about a socioscientific issue
Authors: Tomas Louisa , Ritchie Stephen M. , Tones Megan
Published: July 2011

The development of scientifically literate citizens remains an important priority of science education; however, growing evidence of students' disenchantment with school science continues to challenge the realization of this aim. This triangulation mixed methods study investigated the learning experiences of 152 9th grade students as they participated in an online science‐writing project on the socioscientific issue of biosecurity. Students wrote a series of hybridized scientific narratives, or BioStories, that integrate scientific information about biosecurity with narrative storylines. The students completed an online Likert‐style questionnaire, the BioQuiz, which examined selected aspects of their attitudes toward science and science learning, prior to their participation in the project, and upon completion of the writing tasks. Statistical analyses of these results and interview data obtained from participating students suggest that hybridized writing about a socioscientific issue developed more positive attitudes toward science and science learning, particularly in terms of the students' interest and enjoyment. Implications for research and teaching are also discussed. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 48: 878–900, 2011