bluuebunny/crossref_metadata_2025 huggingface dataset:
Variation in Utilization of Computed Tomography Imaging at Tertiary Pediatric Hospitals
Authors: Lodwick Daniel L. , Cooper Jennifer N. , Kelleher Kelly J. , Brilli Richard , Minneci Peter C. , Deans Katherine J.
Published: October 2015

BACKGROUND:

Recent efforts have focused on reducing computed tomography (CT) imaging in children. Although published reports show variability in CT scanning for specific indications, an assessment of the effects of institutional factors (case-mix or hospital volume) on the rate of CT scanning for any indication is necessary to better understand variability across pediatric hospitals.

METHODS:

Data from 2009 to 2013 on inpatient, observation, and emergency department (ED) encounters were extracted from the Pediatric Health Information System. Chronological trends and institutional variability in CT scan rates were examined by using negative binomial regression models. Case-mix was adjusted by using All Patient Refined Diagnosis Related Groups and severity level.

RESULTS:

Thirty hospitals were included. There were 12 531 184 patient encounters and 701 644 CT scans resulting in a mean of 56 scans per 1000 encounters (range: 26–108). The most common scan types were head (60.1%) and abdomen/pelvis (19.9%). There was an inverse relationship between the CT scan rate and hospital volume (P = .002) and a direct relationship between the CT scan rates for inpatient/observation and ED encounters (P < .001). The rate of CT imaging decreased from 69.2 to 49.6 scans per 1000 encounters during the study period (P < .001).

CONCLUSIONS:

The overall use of CT imaging is decreasing, and significant variability remains in CT use across tertiary pediatric hospitals. Hospital volume and institutional-level practices account for a significant portion of the variability. This finding suggests an opportunity for standardization through multi-institutional quality improvement projects to reduce CT imaging.
Public Policy to Protect Children From Tobacco, Nicotine, and Tobacco Smoke
Authors:   SECTION ON TOBACCO CONTROL, Groner Judith A. , Walley Susan C. , Etzel Ruth A. , Wilson Karen M. , Farber Harold J. , Balk Sophie J. , Groner Judith A. , Moore John E.
Published: October 2015

This Policy Statement was revised. See https://doi.org/10.1542/peds.2023-061804.

Tobacco use and tobacco smoke exposure are among the most important health threats to children, adolescents, and adults. There is no safe level of tobacco smoke exposure. The developing brains of children and adolescents are particularly vulnerable to the development of tobacco and nicotine dependence. Tobacco is unique among consumer products in that it causes disease and death when used exactly as intended. Tobacco continues to be heavily promoted to children and young adults. Flavored and alternative tobacco products, including little cigars, chewing tobacco, and electronic nicotine delivery systems are gaining popularity among youth. This statement describes important evidence-based public policy actions that, when implemented, will reduce tobacco product use and tobacco smoke exposure among youth and, by doing so, improve the health of children and young adults.
Global Climate Change and Children’s Health
Authors:   COUNCIL ON ENVIRONMENTAL HEALTH, Paulson Jerome A. , Ahdoot Samantha , Baum Carl R. , Bole Aparna , Brumberg Heather L. , Campbell Carla C. , Lanphear Bruce P. , Lowry Jennifer A. , Pacheco Susan E. , Spanier Adam J. , Trasande Leonardo
Published: October 2015

This Policy Statement was revised. See https://doi.org/10.1542/peds.2023-065504.

Rising global temperatures are causing major physical, chemical, and ecological changes in the planet. There is wide consensus among scientific organizations and climatologists that these broad effects, known as “climate change,” are the result of contemporary human activity. Climate change poses threats to human health, safety, and security, and children are uniquely vulnerable to these threats. The effects of climate change on child health include: physical and psychological sequelae of weather disasters; increased heat stress; decreased air quality; altered disease patterns of some climate-sensitive infections; and food, water, and nutrient insecurity in vulnerable regions. The social foundations of children’s mental and physical health are threatened by the specter of far-reaching effects of unchecked climate change, including community and global instability, mass migrations, and increased conflict. Given this knowledge, failure to take prompt, substantive action would be an act of injustice to all children. A paradigm shift in production and consumption of energy is both a necessity and an opportunity for major innovation, job creation, and significant, immediate associated health benefits. Pediatricians have a uniquely valuable role to play in the societal response to this global challenge.
Mambe en contextos urbanos, o la producción de nuevas modalidades de consumo
Authors: Cure Salima
Published: October 2015

En este artículo se analiza el consumo del mambe amazónico en contextos urbanos y entre diversos sujetos no indígenas en las ciudades de Leticia y Bogotá. Se trata de un consumo en constante aumento que me llevó a preguntarme en cuáles contextos culturales está siendo incorporada la sustancia y con cuáles significados. En Leticia, uno de los escenarios contemplados fue el de la Universidad Nacional, Sede Amazonia, donde se presenta un difundido consumo de mambe entre investigadores, profesores y estudiantes. En Bogotá, los lugares estudiados fueron el consultorio de un médico homeópata que usa la sustancia en contextos terapéuticos y una comunidad espiritual guiada por un líder indígena re-etnizado. El análisis realizado profundiza en las relaciones sociales que se tejen en las nuevas trayectorias de circulación y consumo del mambe, así como en la creación de nuevos escenarios de relaciones interétnicas, de construcción de representaciones sobre lo indígena, de constitución de identidades de quienes han incorporado el mambe en diversas prácticas y de nuevos significados y modos de consumo de la sustancia.
Documentación de las prácticas lingüísticas y socioculturales de la Gente de centro, Amazonia noroccidental
Authors: Fagua Rincón Doris
Published: October 2015

Ante el peligro de extinción de las lenguas originarias, el proyecto “Documentación de las lenguas de la Gente de centro”, realizado a través del programa DoBeS (Dokumentatio Bedrohter Sprachen) del mpi (Max Planck Institute) en convenio con el iiap (Instituto de Investigaciones de la Amazonía Peruana), ilustra la documentación lingüística como medio para salvaguardar y proteger el patrimonio sociocultural amazónico. Ofrecemos aquí una rápida caracterización tanto de la Gente de centro —una de las auto-denominaciones de las comunidades con las cuales se ha adelantado dicho proyecto— como de algunos de los programas informáticos y formatos utilizados en la documentación sociocultural; al final exponemos las proyecciones en cuanto transferencia de uso de estas herramientas metodológicas a la comunidad regional y nacional de hablantes de lenguas amenazadas y sus estudiosos.
Modelowanie aktywności nabywców mieszkań na rynku województwa zachodniopomorskiego
Authors: Foryś Iwona , Batóg Barbara
Published: October 2015

The activity of participants on the housing market is related to the economic situation of the households, which itself is related to the overall business climate. The tendency for activity on the housing market to weaken during economic recession is not the same on different local markets. The aim of the paper is to analyse the intensity of the purchase-sale transactions during different business cycles in the West Pomeranian voivodship. The research includes analysis of the number of transactions in time, split into different business cycles or different seasons. The dependency of the number of purchase-sale transactions on the housing market and economic variables such as household income, sales revenue, retail sales and the unemployment rate is also analysed. The econometric models with lagged variables and time series models with seasonality are also applied. The data concerning transactions come from the real estate price and value registers from the District Governor's Office, the National Bank of Poland and the Central Statistical Office.
The Problem of Zero Cells in the Analysis of Contingency Tables
Authors: Brzezińska Justyna
Published: October 2015

Log-linear analysis is a statistical tool used to analyse the independence of categorical data in contingency tables. With this method, any number of nominal or ordinal variables can be analysed: interactions can be included in the model, various types of association can be analysed, and the analysis provides a formal model equation. Although log-linear analysis is a versatile statistical method, there are some limitations in using it due to zero cells. Zero cells in contingency table are of two types: fixed (structural) and sampling zeros. Fixed zeros occur when it is impossible to observe values for certain combinations of the variable. Sampling zeros are due to sampling variations and the relatively small size of the sample when compared with a large number of cells. In the paper several options will be presented for how to deal with zero cells in a table. All calculations will be conducted in R.
Rynek energii ze źródeł odnawialnych w Unii Europejskiej - analiza statystyczna
Authors: Frodyma Katarzyna
Published: October 2015

The ongoing dynamic development of civilization has translated into growing demand for energy. The use of traditional energy sources such as coal, oil and natural gas is not only associated with an increase in pollution, but also causes the depletion of natural resources. Renewable sources of energy are an alternative to non-renewable energy sources such as fossil fuels. The main aim of this article is to assess the changes occurring in the market of renewable energy in the European Union. Based on available data, countries were ordered linearly, according to the share of energy from renewable sources they used to produce electricity. Changes in how energy from renewable sources is obtained are discussed. The countries were classified according to how they obtained energy from renewable sources.
Overlapping Generation Models with Heterogeneous Agents and Aggregate Uncertainty in Macroeconomic Modelling
Authors: Acedański Jan
Published: October 2015

The paper introduces the methodology of the overlapping generations models with heterogeneous agents and aggregate uncertainty - macroeconomic, stochastic general equilibrium models that account for consumer heterogeneity mainly with respect to age and wealth. Taking as an example my own model, which additionally allows for labour market status and skill heterogeneity, I show how consumer consumption and investment decision rules are derived. I also provide a detailed discussion of the most popular computational algorithms used to deal with those models. The model is then used to examine welfare gains from eliminating business cycle fluctuations on the labour market in Poland for different groups of consumers.
Model grawitacyjny jako narzędzie analizy handlu zagranicznego
Authors: Klimczak Łukasz
Published: October 2015

The aim of the paper is to determine whether a standard gravity model of trade can work effectively or if a need exists to supplement it with additional measures of "distance". The region of the Western Balkans from 1995 to 2012 was studied. The estimation results of the standard model are compared to the results of the model augmented by variables: border effect, war and post-war effects, minorities, difference in development, religious and language distance, FTA and FDI stock. In order to check for robustness of the results, apart from "pooled" type estimation, models with random effects, one-way and two-way fixed effects were estimated. A model with alternative explanatory variables was also considered. The findings show that there are a number of trade determinants specific to this region, which need to be included in the model. The most important are: similarities in language and religious structures, wars and free trade agreements.
Milestones of chemical technology institute: our past and present
Authors: Bezmaternykh M. A. , Selezneva I. S
Published: October 2015

The article is devoted to the 95th anniversary of the Chemical technological Institute (CTI) of the Ural Federal University named after the first President of Russia B. N. Yeltsin (UrFU), which will be held in October 2015. Over the years Chemical technological Institute (CTI) has undergone many structure transformations in accordance with the tasks which were set before it the time and the development of our country. Currently this is a fairly large educational and research Institute, which employs more than 100 lecturers including more than 70 associate professors – candidates (Dr), 30 professors – doctors of Sciences (DSc), 3 academics and 1 corresponding member of RAS, trained more than 850 students.
Quantitative assessment of reentrainment in the electrocyclone
Authors: Titov A. G. , Gil'vanova Z. R. , Shevchenko E. A. , Masnaviev M. K. , Bir A. A.
Published: October 2015

The paper was devoted to the investigation of the reentrainment which was a parasitic effect incipient at the gas-cleaning systems – cyclones. It was demonstrated that the reentrainment. Arises at the speed of the aerosol from 14 to 27 m/sec. The quantitative characteristics of the reentrainment were determined.
Evaluation of Delayed Puberty in Adolescents with Cleft Lip/Palate
Authors: Crês Maria Cristina , Marques Ilza Lazarini , Bettiol Heloisa
Published: October 2015

Objective

To assess the frequency of delayed puberty in adolescents with cleft lip and/or cleft palate (CL/P).

Design

This was a cross-sectional study of 203 patients with CL/P and no associated syndromes treated at the Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo, Bauru, Brazil. We evaluated boys aged 14-19 years and girls aged 13-18 years. The patients were classified according to Tanner stages of sexual development. The age of menarche was recorded. Patients were assigned to three groups according to cleft type: isolated cleft lip (CL), cleft lip and palate (CLP), and isolated cleft palate (CP). The results were expressed as frequencies and averages and compared with pubertal changes described for typically developing adolescents as reported in the literature.

Results

Subjects were 115 boys and 88 girls. All boys in the CL group and the CP group had already started puberty, and two boys in the CLP group (2.3%) had delayed puberty. All girls had started puberty. The average age at menarche was 12.3 years in the CL group, 12.1 years in the CLP group, and 12.5 years in the CP group.

Conclusions

The frequency of delayed puberty and the average age at menarche in adolescents with CL/P and no associated genetic syndromes or anomalies were within the expected range for typically developing adolescents (i.e., those without CL/P) in the same age group.
Blepharophimosis, Ptosis, and Epicanthus Inversus Syndrome: Expanding the Phenotype
Authors: Kaba Sultan , DoğAn Murat , Bulan Keziban , Demir Nihat , Üner Abdurrahman , Deniz Bulut Mehmet , Kocaman Selami
Published: October 2015

We present a 3-month-old girl who displayed typical clinical characteristics of blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES). She was referred to our clinic with an initial diagnosis of Down syndrome. Clinical features of elevated follicle stimulating hormone and low estradiol levels in the case were diagnosed as BPES syndrome and were consistent with BPES type 2. To date, there are no cases of BPES with cleft palate and cardiomyopathy, suggesting that these novel findings can be part of this condition.
Antenatal Ultrasound Detection of Cleft in Western Australia from 2003 to 2012: A Follow-Up Study
Authors: Nicholls W. , Jennings R. , Yeung Y. , Walters M. , Hewitt B.
Published: October 2015

Aim

To investigate trends in the rate of antenatal detection of cleft lip and palate (CLP) patients referred to the CLP Unit at Princess Margaret Hospital for Children in Perth, Western Australia during the period 2003-2012 and compare data with a previously published report covering the years 1996-2003.

Methods

This is a single-center, retrospective survey of antenatal transabdominal ultrasound screenings of mothers of infants born between July 1, 2003 and June 30, 2012 that were referred to the CLP Unit at Princess Margaret Hospital.

Results

Detection rates of oral clefts increased significantly when compared with outcomes reported in the same population between 1996 and 2003 ( P < .05). An overall detection rate of 71.7% (165/230) was achieved for clefts involving lip and palate. Detection of isolated cleft palate (1/99) and microform (0/8) remained elusive. Most detections (76.5%) were achieved at 15 to 20 weeks of gestational age, corresponding with routine anatomical screening. A further 16.8% were detected post-20 weeks of gestation. Scans were performed by specialist obstetricians, and sonography clinics reported a detection rate of 84.6% (55/65), whereas nonspecialist clinics reported a detection rate of only 67.1% (110/164).

Conclusion

The antenatal detection rates of oral clefts involving the lip have improved to the extent that the majority of mothers are now being referred to a cleft unit in Western Australia prior to the births of their children. As a result of this improvement, antenatal counseling is now a common facet of cleft management.
DOZE ANOS DE ESCRAVIDÃO: BREVE ANÁLISE JURÍDICA
Authors: Da Silva Waldimeiry Correa , Dos Santos Adriana Caetana
Published: October 2015

O presente artigo tem como objetivo promover a discussão crítico jurídica do filme Doze Anos de Escravidão (12 years a slave de Steve McQueen, 2014) a partir da análise da escravidão, do tráfico de pessoas, e do trabalho forçado, considerando os seus conceitos, os elementos constitutivos do tipo e a caracterização desses institutos com base nos instrumentos legais internacionais pertinentes ao assunto, bem como por meio do referencial teórico adequado. Para tanto, o estudo é realizado através do método hipotético-dedutivo, a partir de um visionado geral das cenas pontuais que envolvem o contexto do tráfico de pessoas para fins escravidão, permitindo um conhecimento sobre a realidade da escravatura de outrora e aproximando a discussão acerca das práticas atuais desse universo de exploração e violação dos direitos humanos. Dessa forma, chega-se a conclusão de que o filme contribui para o esclarecimento das questões que envolvem a exploração por meio da escravidão e que essa prática é algo que não ficou adstrito ao passado, sendo presente na contemporaneidade apresentando-se em moldes distintos, embora com a mesma finalidade: explorar economicamente a mão-de-obra humana.
UM ESTUDO BIBLIOMÉTRICO SOBRE DIREITO DO CONSUMIDOR
Authors: LOURO ALAMIR COSTA
Published: October 2015

Na evolução do surgimento dos Direitos (VASAK, Karel 1982), sua terceira geração, ou dimensão, que são aqueles que buscam tutelar direitos coletivos e difusos, o ‘Direito do Consumidor’ é historicamente destaque. Já ‘Consumidor’ é um tema mundialmente estudado por distintas áreas do conhecimento humano, carregando em si várias interpretações e possibilidades epistemológicas que nesse artigo serão discutidas sucintamente. No Brasil, a relevância desses assuntos se repete. Assim sendo, este artigo possui o objetivo de efetivar um levantamento sobre pesquisas publicadas inicialmente em periódicos acadêmicos e posteriormente, e de forma mais efetiva, no maior site sobre a área de conhecimento “Direito” no Brasil, foram encontrados artigos postados nos últimos 17 anos. Para tal, utilizou-se o método descritivo e bibliográfico, com abordagem quantitativa. Após a análise dos dados, foi possível observar a relevância da necessidade de uma discussão mais acadêmica sobre Direito do Consumidor. Concomitantemente a isso, uma predominância dos princípios como assunto relacionado pode indicar uma incipiência da discussão acadêmica.
A COMPANHIA DE JESUS: MODELO INOVADOR E MODERNIZANTE DO ENSINO NO INÍCIO DOS TEMPOS MODERNOS
Authors: Mainka Peter Johann
Published: October 2015

Por volta de 1500, na virada da Idade Média para os Tempos Modernos, Estado e sociedade na Europa em geral e no Sacro Império Romano-Germânico passaram por transformações diferentes e profundas. Nesse período histórico de continuidade e mudança, de tensões e contradições, de tradição e inovação, a Companhia de Jesus, recém-fundada, se tornou um modelo inovador e modernizante da igreja católica, de Estado e sociedade e, especialmente, do ensino médio e superior. No foco deste artigo, colocaremos o momento histórico de reviravolta e a Companhia de Jesus que, como representante exemplar de um novo modelo de inovação e modernização, tornou-se o instrumento principal da Renovação Católica e da Contrarreforma no início dos Tempos Modernos, adquirindo monopólio no ensino médio e superior católico do Sacro Império Romano-Germânico, de quase toda Europa e, também, no Ultramar.
História e memória educacional na região oeste do Paraná
Authors: Silva João Carlos Da
Published: October 2015

Examina a importância dos arquivos na preservação do patrimônio documental nas esferas governamentais. Explicar o passado, prenhe dos acontecimentos humanos, talvez seja e a principal função social do historiador. Mediante suas fontes, consiste a rigor dar significado as atitudes, valores, intenções e convenções que fazem parte das ações humanas. Pretendemos com este artigo calcado em estudo bibliográfico e levantamento em arquivos escolares, pontuar alguns elementos históricos acerca da constituição da escolarização em Cascavel. O desafios do trabalho do historiador da educação, consiste num esforço constante fazer suas fontes falarem sobre os homens, sobre a sociedade que as produziu. A qualidade do conhecimento histórico depende da relação dos historiadores com as fontes. E uma relação mais sólida com as fontes, só vai ser possível, quando ele não precisar gastar boa parte do tempo de pesquisa para localizá-las nos arquivos
Microbiome impact on metabolism and function of sex, thyroid, growth and parathyroid hormones.
Authors: Kunc Michał , Gabrych Anna , Witkowski Jacek M
Published: October 2015

Commensal bacteria and their genes associated with host are known as microbiome. In recent years, microbial influence on host endocrine system has been under detailed investigation. The role of microbiome in the pathogenesis of insulin resistance and obesity, the function of hypothalamic-pituitary-adrenal axis and secretion of hormones regulating appetite is well described in world literature. In this article we discuss poorly reviewed issues: the microbiome role in modulation of non-peptide (sex and thyroid) and peptide (growth hormone and parathyroid hormone) functions. Understanding complex bidirectional relations between host endocrine system and bacteria is of fundamental importance to understanding microbial impact on host reproduction, risk of endocrine-related cancers, pathogenesis of non-thyroidal illness syndrome, growth failure in children and hormonal changes during chronic kidney disease. This article also highlights effects of dietary compounds on microbiome composition and bacterial enzymes activity, and thus host hormonal status.
Simulating Maize Yield and Biomass with Spatial Variability of Soil Field Capacity
Authors: Ma Liwang , Ahuja Lajpat R. , Trout Thomas J. , Nolan Bernard T. , Malone Robert W.
Published: October 2015

Spatial variability in field soil properties is a challenge for system modelers who use single representative values, such as means, for model inputs, rather than their distributions. In this study, the root zone water quality model (RZWQM2) was first calibrated for 4 yr of maize (Zea mays L.) data at six irrigation levels in northern Colorado and then used to study spatial variability of soil field capacity (FC) estimated in 96 plots on maize yield and biomass. The best results were obtained when the crop parameters were fitted along with FCs, with a root mean squared error (RMSE) of 354 kg ha−1 for yield and 1202 kg ha−1 for biomass. When running the model using each of the 96 sets of field‐estimated FC values, instead of calibrating FCs, the average simulated yield and biomass from the 96 runs were close to measured values with a RMSE of 376 kg ha−1 for yield and 1504 kg ha−1 for biomass. When an average of the 96 FC values for each soil layer was used, simulated yield and biomass were also acceptable with a RMSE of 438 kg ha−1 for yield and 1627 kg ha−1 for biomass. Therefore, when there are large numbers of FC measurements, an average value might be sufficient for model inputs. However, when the ranges of FC measurements were known for each soil layer, a sampled distribution of FCs using the Latin hypercube sampling (LHS) might be used for model inputs.
The Cost of Compliance: FIN 48 and Audit Fees
Authors: Erickson Matthew J. , Goldman Nathan C. , Stekelberg James
Published: October 2015

Effective for fiscal years beginning after December 15, 2006, FIN 48 significantly altered uncertain tax benefit (UTB) recognition and disclosure requirements relative to its predecessor standard, FAS 5. We examine the effect of the new standard on audit pricing. We first document that UTB-related audit fees increased following the implementation of FIN 48. However, we also find that this increase is primarily driven by a spike in the audit pricing of UTBs in 2007. Indeed, we find that the audit pricing of UTBs in the 2008–2012 period is not significantly different from that of the 2002–2006 period. We interpret these results to indicate that although firms incurred significant FIN 48 implementation costs, the ongoing audit pricing of UTBs under FIN 48 is similar to that of FAS 5. Our findings suggest that any potential benefits of FIN 48 may outweigh associated costs related to a temporary increase in audit fees.

JEL Classifications: H25; M40; M41; M42; M48.
The impact of consolidation and interparticle forces on cohesive cement powder
Authors: Turki Djamel , Fatah Nouria , Saidani Messaoud
Published: October 2015

Cement powder particles of micronic size tend to form agglomerates due to the influence of interparticle forces (Van der Waals forces). The formation of agglomerates results in an increased air-void in the solid structure (aerated powder) requiring an increase in water demand to sustain the feasibility of the structure. Consequently, if the compound formed is not stabilized, it would have low mechanical strength that may result in cracking of hardened cement. In this study, the results of cement powder consolidation and its flow properties show that its behaviour is controlled by internal forces (Van der Waals) and external forces (elastic and plastic). These forces have a direct influence on the powder structure, leading to a variable packing behaviour (void reduction). Consolidated cement powder shows a decrease in the void structure leading to a more efficient material. This study intends to determine the impact of interaction forces between cement particles during consolidation.
A new constitutive approach to large strain plastic deformation
Authors: Korbel Andrzej , Bochniak Włodzimierz , Ostachowski Pawel , Paliborek Anna , Łagoda Marek , Brzostowicz Adelajda
Published: October 2015

This paper presents the results of studies regarding the effect of nonconventional plastic deformation on the mechanism of plastic flow of metals. The applied method, called KOBO extrusion, in which monotonic large deformation is accompanied by cyclic reversible plastic twisting, falls into the category of severe plastic deformation. The cyclic reversible plastic twisting, which proved to be redundant in terms of changes in the material's geometry, appears to be a particularly efficient source of point defects. The experimentally proven Newtonian viscosity of metals at low temperatures under KOBO extrusion conditions implies that it is necessary to conduct a study on the crystal plasticity from the point of view of the constitutive law in which a crystal's viscosity totally controls the kinetics of the process. The well known dependency of the viscosity parameter on the diffusion coefficient, which, in turn, is a function of point defect concentration, dictates the link between the frequency of reversible plastic twist and the crystal's viscosity and, consequently, determines the mode of plastic flow. The results of this work provide experimental verification which justifies this new approach to crystal plasticity.
Effect of heat treatment on the microstructure and dielectric properties of plasma-sprayed barium titanate films
Authors: Pakseresht Amir Hossein , Rahimipour Mohammad Reza , Vaezi Mohammad Reza , Salehi Mehdi
Published: October 2015

Thick films of barium titanate were produced by using atmospheric plasma spraying, and their microstructures and dielectric properties were analyzed. X-ray diffraction analysis of the coating was performed to study the phase and structural properties. The results showed that the crystalline structures of the initial powder and the produced film were different and the latter displayed some amorphous phase. The percentage of amorphous phase varied with the amount of melted particles. The analysis of dielectric properties of the barium titanate films showed that these films have a minimum relative permittivity of 85 at room temperature. This was increased up to 165 by heat treatment at 1050°C for 3 h, due to the crystallization of amorphous phase and reduction of some of the defects because of the thermal spraying.
Wear behavior of Ni/WC surface-infiltrated composite coating on copper substrate
Authors: Yang Gui-rong , Song Wen-ming , Li Jian , Ma Ying , Lu Jin-jun , Hao Yuan
Published: October 2015

Ni/WC surface-infiltrated composite coating was fabricated on copper alloy substrate through vacuum infiltration casting using Ni-based alloying powder and with different WC particle contents as raw materials. The wear behavior of Ni/WC surface-infiltrated composite coating was investigated using a block-on-ring tester at different loads and sliding speeds at room temperature. Results show that the wear rate of Ni/WC surface-infiltrated composite coating decreased to approximately one-sixth of the wear rate of the Ni-based alloy infiltrated coating. This phenomenon resulted from the supporting function of WC particles under varying loads applied on the specimen surface and the antifriction effect of the transformation layer. Wear rate was reduced by the Ni/WC-infiltrated composite coating with increasing load, especially when the load exceeded 100 N. The friction coefficient decreased with increasing sliding speed for all infiltrated coatings at any load condition. The reduction in the friction coefficient at high sliding speed was larger than that at low sliding speed with increasing load. The wear mechanism was dominated by oxidation under all experimental conditions and accompanied by adhesion and abrasion mechanisms at high load and high sliding speed.
Magnetocaloric and Hopkinson effects in slowly and rapidly cooled Gd7Pd3
Authors: Talik Ewa , Guzik Adam , Oboz Monika , Zajdel Paweł , Ziółkowski Grzegorz
Published: October 2015

Gd7Pd3 intermetallic compound was prepared as slowly cooled polycrystal and rapidly cooled (rc) casts. The slowly cooled polycrystalline samples were obtained by melting in an induction coil. The rc-cast Gd7Pd3 sample was obtained by means of a mould casting technique. The samples were characterized by means of X-ray diffraction, SQUID magnetometry and scanning electron microscopy in order to elucidate the Hopkinson effect and magnetocaloric properties in relation to the technological aspects. The investigated ferromagnetic system is sensitive to grain size. The magnetocaloric and Hopkinson effect decreases with the decrease of the grain size. The results were compared to the data of single crystal obtained by the Czochralski method from a levitating melt.
Synthesis of dihydropyrazole derivatives using modified calcium oxide as a solid basic catalyst
Authors: Tang Ying , Zhang Li , Wang Shanshan , Zhang Jie , Miao Yanqing
Published: October 2015

Abstract

A highly efficient method for the synthesis of dihydropyrazole derivatives has been established by using CaO as a solid basic catalyst. It was found that a 77.1% yield of 3,5-diphenyl-4,5-dihydropyrazole-1-carboxamide was obtained at ratio of aminourea hydrochloride/chalcone of 1.2:1 after 3 h at a reaction temperature of 65°C. The reaction efficiency was greatly enhanced, with the 3,5-diphenyl-4,5-dihydropyrazole-1-carboxamide yield reaching 91.2%, when the commercial CaO was modified by benzyl bromide in a simple way. The effects of modification and reaction conditions on the yields as well as the mechanism were studied thoroughly. From the results of FTIR and thermogravity analysis characterisation, the modifier was shown to be bonded on the surface of CaO chemically, and almost no Ca(OH)2 was formed during the modification process. The type of chalcone has a strong influence on the yield of dihydropyrazole derivative.
Investigation of hydrogen reduction of cuprous sulfide through the Law of Additive Reactions using a virtual model
Authors: Abolpour Bahador , Afsahi M. Mehdi
Published: October 2015

ABSTRACT

A virtual structural model has been developed for predicting the behaviour of cuprous sulfide reduction by hydrogen in the presence of lime. This model treats the complex successive reactions as a simple reaction. Then the kinetic and structural parameters of this assumed simple reaction were obtained by fitting the experimental data to the additive reaction times equation. Finally, the results predicted by the virtual model have been evaluated and validated using experimental data, and compared with those of mathematical modelling. This virtual model could be useful for predicting the behaviour of complex reactions without needing time-consuming computations.
Dehydrogenation-hydrogenation of methylcyclohexane-toluene system on 1.0 wt% Pt/zeolite beta catalyst
Authors: Usman Muhammad R. , Alotaibi Faisal M. , Aslam Rabya
Published: October 2015

The dehydrogenation of methylcyclohexane is a reversible reaction where methylcyclohexane is dehydrogenated to toluene and hydrogen in the forward reaction while the hydrogenation of toluene occurs is the reverse reaction. In the present work, both the forward and the reverse reactions were studied over the same catalyst: 1.0 wt% Pt/zeolite beta. The catalyst was prepared using the ion exchange method and it was characterised using ICP-OES, XRD, SEM, XPS, N2-BET, and NH3-TPD. The catalytic reactions were studied in a 1.02 cm internal diameter fixed bed tubular reactor under integral conditions and the effect of reaction operating conditions were studied on both the forward and reverse reactions. The kinetic modelling of the overall reactions, as well as of the by-products formed in the forward reaction, was carried out using simple power law models.
Diels-Alder versus 1,3-dipolar cycloaddition pathways in the reaction of C20 fullerene and 2-furan nitrile oxide
Authors: Siadati Seyyed Amir , Mirabi Ali
Published: October 2015

As one of the smallest carbon cages, C20 and its properties are very important. The nature of these compounds, and the development of procedures for their functionalisation for end-use in nano sized devices, have become important fields. Both Diels–Alder and 1,3-dipolar cycloaddition reactions are appropriate strategies to functionalise carbon nano tubes and C60 fullerenes. In this regard a comparison between two pathways of interaction between C20 and 2-furan nitrile oxide has been performed here to determine which reaction, Diels–Alder or 1,3-dipolar addition, is more suitable for functionalisation of C20. The results showed that 1,3-dipolar cycloaddition is faster than the Diels–Alder reaction for the functionalisation of C20 fullerene by 2-furan nitrile oxide.
DNA Cleavage Activity: Comparison of two Lanthanum Complexes Based on Aza-Crown Ethers with Different Numbers of Nitrogen Atoms
Authors: Yu Lan , Li Fang-zhen , Xie Jia-qing , Cai Shulan
Published: October 2015

Based on the unique characteristics of lanthanum ion and aza-crown ethers, the lanthanum complexes of two aza-crown ether (L1: 1,10-Dioxa-4,7,13,16-tetraazacyclo-octadecane and L2: 1,4,10,13-tetraoxa-7,16-diazacyclooctadecane) were designed and synthesised. The interaction between these two complexes and DNA was measured by UV-Vis spectroscopy and gel electrophoresis. Moreover, a series of experiments of cleavage of pUC19 DNA were conducted to illustrate the acidity, time and concentration effects. The results indicated that the two metal complexes can accelerate the breakage of DNA from its supercoiled form (form I) to the nicked form (form II) at near-physiological conditions, and the optimum acidity of DNA catalytic cleavage is pH=6.5 and pH=7.0 for LaL1 and LaL2, respectively. Furthermore, the LaL1 exhibited better cleavage activity than LaL2 under the same conditions, thus supercoiled DNA was thoroughly cleaved to the nicked form under the appropriate conditions. The hydrolytic mechanism was verified by applying several oxygen-scavengers to the DNA catalytic cleavage.
A proposed kinetic model for hydrogen sorption in MgH2
Authors: Rahman Md. Wasikur
Published: October 2015

The role of ternary Mg–Nb oxides on H2 absorption and desorption properties of ball milled MgH2 is discussed on the basis of a kinetic model involving the formation of reaction pathways of ternary oxide species with easier splitting of H2 that facilitate the transport of H2 into the solid structure. The kinetic model comprised three key steps: dissociation of molecular hydrogen into H atoms, diffusion of H into Mg to form MgH2 during adsorption, and successive recombination of H–H on the surface of the additives during desorption to make a pathway for H2 sorption in the structure. The presence of transition metal oxides remarkably increases the H2 sorption rates of nano-structured MgH2, as determined by a volumetric Sievert apparatus. The H2 desorption rate increases with increasing temperature from 593 to 673 K and under the same conditions, the absorption rate decreases. The most promising results were obtained for Mg3Nb6O11-doped MgH2 nanoparticles. The MgH2/Mg3Nb6O11 system is completely dehydrogenated at 673 K under 0.1 MPa H2 and the samples fully rehydrogenated at 613 K under 2.5 MPa H2 pressure. Activation energies were obtained for MgH2/Mg3Nb6O11 mixture, and without additive (ball milled MgH2), to be 88 and 127 kJ mol−1, respectively, underlying the effect of the ternary additive.
Bacillus Calmette-Guérin (BCG) Treatment Failures in Non-Muscle Invasive Bladder Cancer: What Truly Constitutes Unresponsive Disease
Authors: Steinberg Ryan L. , Thomas Lewis J. , O’Donnell Michael A.
Published: October 2015

Bacillus Calmette-Guérin (BCG) remains the most effective intravesical therapy for non-muscle invasive bladder cancer but will fail in up to 40% of patients. The ability to identify patients who are least likely to respond to further BCG therapy allows urologists to pursue secondary treatments more likely to convey a recurrence or survival benefit to the patient. We examined the literature to determine what constitutes BCG unresponsive disease. After review, we believe that BCG unresponsive disease should be defined as (1) patients with recurrent high grade T1 disease within 6 months of their primary tumor after at least one course of BCG or patients who have failed at least 2 courses of BCG with either (2) persistent or recurrent pure papillary (Ta) disease within 6 months or (3) persistent or recurrent carcinoma in situ (CIS) within 12 months.
Alvimopan in an Enhanced Recovery Program Following Radical Cystectomy
Authors: Hamilton Zach , Parker Will , Griffin Josh , Isaacson Tanner , Mirza Moben , Wyre Hadley , Holzbeierlein Jeffrey , Lee Eugene K.
Published: October 2015

Background: Radical cystectomy (RC) carries a high complication rate, including post-operative ileus. Alvimopan is an FDA approved peripherally acting μ-opioid receptor antagonist that has shown favorable results for improved recovery of gastro-intestinal function resulting in decreased hospital length of stay. Many enhanced recovery pathways (ERP) have been published demonstrating improved outcomes with decreased hospital stay and morbidity.

Objective: We evaluated the addition of alvimopan to an ERP in patients undergoing RC.

Methods: Patients undergoing RC at our institution during the implementation phase of alvimopan to our established ERP were retrospectively reviewed. Effect of alvimopan as it related to the use of nasogastric tubes, time to initiation of regular diet, and length of hospital stay was assessed using Chi-squared and Student’s T-tests. Linear regression was performed for univariate analysis and binary logistic regression was performed as a multivariate assessment of the effect of alvimopan.

Results: Between July 2011 and January 2013, 80 patients were identified who underwent RC under the ERP (34 alvimopan and 46 standard care). Age, sex, neoadjuvant chemotherapy, surgical technique (open vs. robotic), and type of urinary diversion were not different between groups. Alvimopan was associated with a reduction in mean time to regular diet (5.3 vs 4.1 days, p <  0.01) and a reduction in mean length of hospital stay (6.9 vs 5.7 days, p = 0.01). After controlling for other variables, alvimopan usage predicted for shorter time to regular diet and total hospital stay.

Conclusions: Alvimopan may help to improve time to regular diet and decrease hospital stay in patients on an enhanced recovery pathway.
Multiscalar Narratives of a Disaster: From Media Amplification to Western Participation in Asian Tsunamis
Authors: Bonati Sara
Published: October 2015

The international recovery system responds differently to disasters with similar characteristics. It answers to specific motivations that are not necessarily connected to the nature of the disaster. The variability of the answers given not only depends on the type of disaster but also, in particular, on the local social structure and on the transcalar narrative of the disaster used to move communities not directly affected to action. This paper therefore analyses the level of Western involvement in two Asian tsunami recovery plans and the role of the media in attracting Western private donations. To this end, Italian involvement in the two cases is discussed. Beginning with a literature review to support the argument that the media are crucial in stimulating private participation through ‘spectacularizing’ the disaster, this paper illustrates that, when spectacularization is insufficient, the media additionally adopts the strategy of ‘transposition’, leading to ‘appropriation’ of the event. In particular, during the Boxing Day tsunami of 2004, the transposition became the ‘Westernization’ of the narrative of the disaster. The process of transposition or Westernization, however, did not happen with the same modalities in the narrative of the Tohoku tsunami of 2011. In this case, the focus was more on the technological disaster that followed the natural disaster. The author concludes that emotional transposition of the disasters by the media played an important role in stimulating private donations and in spurring governmental relief in both the disasters. Foreign governments, however, are mainly moved by other factors such as ‘flag policy’ or what Olsen et al. (2004) identified as the concept of ‘donor interests’.
Polyethylene Glycol (PEG)-Treated Hydroponic Culture Reduces Length and Diameter of Root Hairs of Wheat Varieties
Authors: Robin Arif , Uddin Md. , Bayazid Khandaker
Published: October 2015

Wheat is an important cereal crop worldwide that often suffers from moisture deficits at the reproductive stage. Polyethylene glycol (PEG)-treated hydroponic conditions create negative osmotic potential which is compared with moisture deficit stress. An experiment was conducted in a growth chamber to study the effects of PEG on root hair morphology and associated traits of wheat varieties. Plants of 13 wheat varieties were grown hydroponically and three different doses of PEG 6000 (w/v): 0% (control), 0.3% and 0.6% (less than −1 bar) were imposed on 60 days after sowing for 20 days’ duration. A low PEG concentration was imposed to observe how initial low moisture stress might affect root hair development. PEG-treated hydroponic culture significantly decreased root hair diameter and length. Estimated surface area reduction of root hairs at the main axes of wheat plants was around nine times at the 0.6% PEG level compared to the control plants. Decrease in root hair diameter and length under PEG-induced culture decreased “potential” root surface area per unit length of main root axis. A negative association between panicle traits, length and dry weight and the main axis length of young roots indicated competition for carbon during their development. Data provides insight into how a low PEG level might alter root hair development.
Converting Sugars to Biofuels: Ethanol and Beyond
Authors: Kang Aram , Lee Taek Soon
Published: October 2015

To date, the most significant sources of biofuels are starch- or sugarcane-based ethanol, which have been industrially produced in large quantities in the USA and Brazil, respectively. However, the ultimate goal of biofuel production is to produce fuels from lignocellulosic biomass-derived sugars with optimal fuel properties and compatibility with the existing fuel distribution infrastructure. To achieve this goal, metabolic pathways have been constructed to produce various fuel molecules that are categorized into fermentative alcohols (butanol and isobutanol), non-fermentative alcohols from 2-keto acid pathways, fatty acids-derived fuels and isoprenoid-derived fuels. This review will focus on current metabolic engineering efforts to improve the productivity and the yield of several key biofuel molecules. Strategies used in these metabolic engineering efforts can be summarized as follows: (1) identification of better enzymes; (2) flux control of intermediates and precursors; (3) elimination of competing pathways; (4) redox balance and cofactor regeneration; and (5) bypassing regulatory mechanisms. In addition to metabolic engineering approaches, host strains are optimized by improving sugar uptake and utilization, and increasing tolerance to toxic hydrolysates, metabolic intermediates and/or biofuel products.
Age-Related Response Bias in the Decoding of Sad Facial Expressions
Authors: Fölster Mara , Hess Ursula , Hühnel Isabell , Werheid Katja
Published: October 2015

Recent studies have found that age is negatively associated with the accuracy of decoding emotional facial expressions; this effect of age was found for actors as well as for raters. Given that motivational differences and stereotypes may bias the attribution of emotion, the aim of the present study was to explore whether these age effects are due to response bias, that is, the unbalanced use of response categories. Thirty younger raters (19–30 years) and thirty older raters (65–81 years) viewed video clips of younger and older actors representing the same age ranges, and decoded their facial expressions. We computed both raw hit rates and bias-corrected hit rates to assess the influence of potential age-related response bias on decoding accuracy. Whereas raw hit rates indicated significant effects of both the actors’ and the raters’ ages on decoding accuracy for sadness, these age effects were no longer significant when response bias was corrected. Our results suggest that age effects on the accuracy of decoding facial expressions may be due, at least in part, to age-related response bias.