bluuebunny/crossref_metadata_2025 huggingface dataset:
Depósitos de vertente e evolução quaternária do planalto do Itatiaia
Authors: Modenesi May Christine
Published: November 2013

Nas médias e baixas encostas do vale dos Lírios e em alvéolos menores da bacia do ribeirão das Flores, encontram-se depósitos correlativos da evolução quaternária do planalto do Itatiaia. Os processos responsáveis pela deposição dos tálus suspensos, concentrações lineares de matacões, depósitos de seixos angulosos e duas gerações de colúvios refletem influências de reativação tectônica e de variações climáticas pleistoceno-holocênicas. Eventos mais antigos e eficientes na liberação de blocos e matacões das vertentes rochosas íngremes - explicados por um conjunto de ações de amplo espectro, que incluiria processos de gelivação - teriam dado lugar a episódios de coluvionamento. Colúvios C I heterométricos, com blocos do regolito, e colúvios C II mais homogêneos e finos, com pequenos seixos e grânulos, resultariam da ação de processos cada vez menos agressivos, capazes de retrabalhar apenas os produtos de fases erosivas anteriores. A diminuição da atividade denudacional nas encostas do planalto favoreceu o preenchimento das várzeas e depressões hidromórficas, com sedimentos holocênicos relativamente finos, e a formação de turfeiras.
Síntese dos conhecimentos e novas concepções sobre a bioestratigrafia do Subgrupo Itararé, Bacia do Paraná, Brasil
Authors: Petri Setembrino , Souza Paulo Alves de
Published: November 2013

Este trabalho constitui-se de uma análise crítica das contribuições paleontológicas publicadas, visando à melhor definição do quadro cronológico e da sucessão bioestratigráfica do Subgrupo ltararé, Bacia do Paraná, Brasil. Esta unidade exibe variadas associações de diferentes fácies, envolvendo depósitos glaciais, periglaciais e provavelmente pós-glaciais (incluindo depósitos marinhos). A análise detalhada da distribuição vertical e lateral dos diferentes táxons sugere idades envolvendo o intervalo compreendido entre o Westphaliano (Carbonífero Superior) e o Kunguriano (Permiano Médio). Observações prévias da mudança da microflora (esporomorfos) entre o Artinskiano e o Kunguriano, com a primeira indicação do surgimento de representantes de florestas no início do Kunguriano, são interpretadas, neste trabalho, como indicativo do fim da glaciação no final do Artinskiano
Neotectônica da área do Alto Rio Pardo (SP e MG)
Authors: Melo Mário Sérgio de , Stein Dirceu Pagotto , Ponçano Waldir Lopes , Bistrichi Carlos Alberto
Published: November 2013

A área da bacia do rio Pardo, a montante da barragem da UHE Armando de Salles Oliveira, foi analisada quanto a características indicativas de atividade neotectônica. Tais estudos, efetuados nas escalas 1:250.000 e 1:50.000, objetivaram fornecer subsídios para previsão do risco sísmico e compreensão da geomorfogênese e dinâmica atual. As características analisadas foram: distribuição dos níveis planálticos e feições morfológicas típicas (lineamentos, rupturas de declive, escarpas rochosas, corredeiras, encostas retilíneas, leques aluviais, capturas, densidade e controle estrutural da drenagem, terraços fluviais), estruturas rúpteis (juntas, falhas) e acumulações neocenozóicas (tálus, colúvios, aluviões em planícies e terraços). A área revelou-se muito pobre em evidências de atividade neotectônica. A maioria das feições morfológicas estudadas bem como as acumulações de depósitos não mostraram padrões de distribuição que permitissem interpretações. As estruturas rúpteis, raras e de difícil análise, permitiram interpretar as principais zonas de movimentações neotectônicas quando associadas a evidências de natureza morfológica. A distribuição dos níveis planálticos e os lineamentos, ambos analisados em escala 1:250 000, revelaram-se as características mais significativas. A idade dos aplainamentos indicou atividade tectônica mais pronunciada no Paleógeno e reativações subseqüentes pouco marcadas no relevo. A correlação destas evidências com dados estruturais revelou estruturação cenozóica orientada principalmente a ENEWSW e NW-SE, refletindo propagação, muito amenizada na área, dos eventos tectônicos da faixa costeira do Sudeste do Brasil. Os procedimentos adotados destacaram a conveniência, para áreas de discreta atividade neotectônica, de análise em escala tanto regional (organização geomorfológica) quanto de detalhe (estruturas). A integração dos dados destas duas escalas de abordagem permitiu chegar às interpretações sobre a evolução neotectônica do alto rio Pardo
A Validity and Reliability Study of a Chinese Assessment Tool for Persons with Moderate to Severe Intellectual Disabilities
Authors: Chan Christopher L.F. , Lai Claudia , Chi Iris
Published: November 2013

This study was designed to test the psychometric properties of the Chinese interRAI Intellectual Disability (ID) tool in a Chinese population with learning disabilities in Hong Kong. The Chinese interRAI ID was prepared based on the original interRAI ID which is a standardized, comprehensive instrument and is designed to evaluate the strengths, preferences, and needs of persons with all levels of ID living in various care settings. A sample of 100 people with moderate to severe intellectual disabilities was assessed with the Chinese interRAI ID and its criterion measures. The subscales of the interRAI ID, including the Cognitive Performance Scale, Depression Rating Scale, Aggressive Behavior Scale, Activities of Daily Living Hierarchy Scale, and Instrumental Activities of Daily Living Involvement Scale, had high internal consistency (Cronbach’s α = .66 to .87) and test–retest reliability (r = .96 to .99; κ = .68 to .81). Comparison of the interRAI ID scales with criterion measures supported concurrent and discriminant validity of these scales. The study results provide preliminary support for the Chinese interRAI ID as a reliable and valid tool for assessing Chinese individuals with learning disabilities in Hong Kong.
Verbal Memory and IQ Predict Adaptive Behavior in Children and Adolescents with High-Functioning Autism Spectrum Disorders
Authors: Puig O. , Calvo R. , Rosa M. , Serna E. de la , Lera-Miguel S. , Sánchez-Gistau V. , Castro-Fornieles J.
Published: November 2013

Adaptive deficits are commonly found in high functioning autism spectrum disorders (HF-ASD) despite of cognitive potential. Most studies have focused on the relationships between adaptive behavior and intellectual quotient (IQ) and have used correlations to study relationships between them. Few studies have analyzed cognitive variables other than IQ as potential predictors of adaptive behavior in HF-ASD using regression methods. This study aimed to analyze the impact of several cognitive variables on adaptive behavior in a sample of children and adolescents with HF-ASD. METHODS: Sample included 16 child and adolescent boys with HF-ASD (age between 7-17 years). Cognitive assessment included measures of general intelligence, visual memory, verbal memory, working memory and problem solving/flexibility tests. Vineland Adaptive Behavior Scales (VABS) was used to evaluate adaptive behavior. To establish the predictive capacity of the cognitive variables for adaptive functioning, linear regression models were fitted for each adaptive domain using a stepwise method. RESULTS: Verbal memory and IQ emerged as the main independent predictors for VABS adaptive scores. The 41% of the variance in Communication was predicted by IQ. The 35% of the variance in Daily Living Skills was predicted by verbal memory. Almost half of the variance in Socialization was predicted by both, verbal memory and IQ (49%). No other cognitive functions were associated with adaptive scores. CONCLUSIONS: The results highlight the strong impact of IQ and verbal memory on adaptive behavior in HF-ASD patients. These findings could contribute to identify potential targets of intervention.
Pharmacologic Management of Aggression in Adults with Intellectual Disability
Authors: Roy Durga , Hoffman Pamela , Dudas Melissa , Mendelowitz Alan
Published: November 2013

Introduction: Aggression is a common behavioral problem seen in patients with intellectual disabilities (ID). The safety and efficacy of second generation antipsychotics (SGAs), mood stabilizers and antidepressants in the management of aggression in these individuals have minimally been studied. This review aims to 1) summarize the studies conducted using second generation antipsychotics, mood stabilizers and antidepressants in treating aggressive behaviors in patient with ID and 2) determine based on the existing literature, which medications have been examined in the most rigorous study design that might suggest the most efficacy for use in clinical practice.
Methods: Literature searches using PUBMED Central, CINAHL Plus, PsychINFO, and Embase databases were conducted using the following terms: intellectual disability/disabilities, mental retardation, developmental disability/disabilities, aggression, agitation, behavior disorder, adult, treatment, management. Studies predominantly including children with ID, and autism/pervasive developmental disabilities spectrum disorders were excluded. Analyses were done by class of medication: SGAs, mood stabilizers and antidepressants. The primary outcome measure was reduction in aggressive or self injurious behaviors as measured by each individual study.
Results: The most rigorous study designs found using these agents were randomized controlled trials (RCT). A total of 10 RCTs were found, the majority being with risperidone (3) and lithium (2). Treatment with risperidone showed reduction in aggression when compared to placebo in most RCTs with the exception of one study in which risperidone was not better than placebo. Both lithium studies showed reduction in aggression when compared to placebo. The most abundant literature exists in retrospective chart reviews. The most commonly studied agent was risperidone which showed reduction in aggression in majority of the studies.
Conclusions: Limited data exists for treatment of aggression in adults with ID. There are very few studies examining pharmacologic agents using RCTs. Given that risperidone and lithium were the most commonly studied agents in the most rigorous experimental design, it is suggested that these two agents prove efficacious for treatment of aggression in patients with ID. Limitations to most of these studies included concomitant psychotropic administration with variations in types and dosing, severity of ID, and the idea that a wide variety of aggression scales were used to assess outcome. Further research with more scientific rigor is required in this field.
Number Sense in Siblings of Children with Mathematical Learning Disabilities: A Longitudinal Study
Authors: Praet Magda , Titeca Daisy , Ceulemans Annelies , Desoete Annemie
Published: November 2013

Number sense, counting and logical thinking were assessed in 14 siblings of children with Mathematical Learning Disabilities (MLD) and in 41 age matched children without family members with MLD. The children were tested in kindergarten and followed up in grade 1. A 0-100 number line estimation paradigm with three formats (Arabic digits, dots and number) was used as a measure of number sense. Results reveal that siblings of children with MLD are less proficient in number line placements compared to non-siblings, with both groups having a logarithmic representation in kindergarten and grade 1. Siblings also differ from non siblings on procedural and conceptual counting knowledge and logical thinking in kindergarten. In addition, our findings suggest that nnumber line estimation in kindergarten is especially predictive for untimed procedural calculation performances in grade 1, whereas procedural counting knowledge is related to timed fact retrieval skills in grade 1. Our findings also reveal that MLD had a familial aggregation. Clinical siblings especially differ from non-clinical siblings on the estimation with Arabic numbers (in kindergarten and grade 1) and number words (in grade 1), pointing to the fact that especially symbolic number line estimation tasks on a 0-100 scale can be used as screeners for MLD. Implications for the understanding and diagnosis of MLD are discussed.
La réussite scolaire des jeunes Québécois issus de l’immigration au secondaire de langue française : une comparaison entre la première et la deuxième génération
Authors: Mc Andrew Marie , Ledent Jacques
Published: November 2013

Cet article dresse un portrait du cheminement scolaire des élèves québécois issus de l’immigration qui ont commencé leur secondaire au secteur français en 1998 et 1999. Les élèves nés à l’étranger sont comparés avec leurs pairs dont au moins un parent est né à l’étranger ainsi que ceux dont les deux parents sont nés au Canada. En premier lieu, nous présentons un profil des trois groupes selon leurs caractéristiques sociodémographiques, leur processus de scolarisation ainsi que les caractéristiques des écoles qu’ils fréquentent. Leur cheminement scolaire est ensuite analysé selon trois indicateurs, le retard scolaire accumulé deux ans après l’entrée au secondaire, la diplomation et le décrochage net qui tient compte des départs de la province et de la fréquentation du secteur des adultes.
Library as Scholarly Publishing Partner: Keys to Success
Authors: McIntyre Gordon , Chan Janice , Gross Julia
Published: November 2013

Many academic libraries are looking at new ways to add value when they deliver services to faculty, and one potential area where the library can provide new services is in partnering with academic staff to support the dissemination of faculty research. Librarians have traditionally helped faculty researchers at the beginning of the research cycle, with the discovery and delivery of information sources. However, they are now playing a role at the end of the research cycle, providing services that support scholarly publishing. This paper examines library participation in faculty-led publishing ventures. In particular, it explores the value that smaller research libraries can provide to faculty editors through journal hosting, which will be analysed through an examination of the successful migration of the Australian Journal of Teacher Education, a faculty-administered journal at Edith Cowan University in Perth, Western Australia, to the University’s institutional repository. This transition provided library staff members at Edith Cowan University opportunities to develop new knowledge and skills in journal publishing, while meeting the journal’s need for a better way to manage a growing influx of article submissions. The resultant faculty-library partnership enabled more effective management of the journal and has contributed to its growing success. The evaluative framework developed to enable assessment of the success of this journal’s transition can help other libraries demonstrate the success of their own journal hosting ventures.
Speaking as One: Supporting Open Access with Departmental Resolutions
Authors: Cohen Madeline , Smale Maura A , Cirasella Jill , Tobar Cynthia , Daniels Jessie
Published: November 2013

Library faculty at the City University of New York (CUNY) have engaged in promoting and advocating for open access publishing at each of our campuses as well as across the University. Inspired by the passing of a faculty senate resolution in support of the creation of an open access institutional repository and associated policies, many CUNY librarians felt the need to raise their level of commitment. In this article, the authors—four library faculty members and one faculty member from outside the library—share their experiences creating and approving open access policies in the library departments of four CUNY schools and promoting open access beyond the libraries. They offer practical advice and guidance for other librarians and faculty seeking to encourage the embrace of open access publishing in departments or other sub-institutional contexts.
Radio Telescope Gets Star Treatment
Authors: Showstack Randy
Published: November 2013

Actress Jodie Foster, who played a scientist in search of extraterrestrial life in the 1997 film Contact, narrates a new promotional film to reintroduce the public to the National Radio Astronomy Observatory's (NRAO) renovated Karl G. Jansky Very Large Array (VLA) radio telescope in New Mexico. The 24‐minute film, Beyond the Visible, which will air in the VLA Visitor Center, focuses on the operation of the telescope and scientific achievements associated with it.
Impacts of U.S. Government Shutdown on Earth Science Teaching and Education
Authors: Singh Ramesh P.
Published: November 2013

The federal government shutdown, apart from the impact on the U.S. economy and cancellation of some important nationally funded research, greatly affected scientists studying Earth and space science across the nation. Much coverage has highlighted how the fallout from this will influence large research projects, but the fallout goes beyond this. In particular, Earth science education involving natural hazards in the United States and in developing countries was put on hold.
Ganymede's auroral footprint has multiple spots
Authors: Balcerak Ernie
Published: November 2013

The moons of giant planets can create a phenomenon called an “auroral footprint,” which is due to an interaction between the moon and the planet's magnetosphere. This phenomenon, which has been observed for Jupiter's moons Io, Europa, and Ganymede as well as Saturn's moon Enceladus, is usually seen as a single spot in the planet's aurora. However, Io has an auroral footprint that is known to be made up of at least three spots. Scientists wondered if a multispot auroral footprint is common or unique to Io.
High‐resolution model captures global atmospheric deep convection
Authors: Schultz Colin
Published: November 2013

When moist air is mixed high into the atmosphere, a process known as deep convection, the motion can give rise to towering storm clouds. Deep convection is also an important process for balancing momentum and energy within the atmosphere. Atmospheric deep convection is a relatively small‐scale physical process, with the motion spanning anywhere from 1 to 10 kilometers. Its effects, though, are globally relevant, dictating storm patterns and climatological changes. Modeling deep convection in a global simulation, then, is challenging because these small‐scale processes need to be represented and tracked across the whole planet.
Near cessation of Eighteen Degree Water renewal in the western North Atlantic in the warm winter of 2011–2012
Authors: Billheimer Sam , Talley Lynne D.
Published: November 2013

The winter of 2011–2012 was a particularly weak season for the renewal of “Eighteen Degree Water” (EDW), the Subtropical Mode Water of the western North Atlantic, as demonstrated by Argo and repeat hydrography. Weak, late winter buoyancy forcing produced shallower than usual winter mixed layers throughout the subtropical gyre, failing to thoroughly ventilate the underlying mode water, and can likely be attributed to the coinciding high, positive phase of the North Atlantic Oscillation (NAO). The only region where EDW was renewed was in the far northeastern Sargasso Sea where it is understood that the Gulf Stream plays a central role in formation; no EDW formed over the large regions of the gyre where deep winter mixed layers driven by surface buoyancy loss normally create EDW. The present investigation evaluates 2011–2012 winter buoyancy content anomalies, surface buoyancy fluxes, and advection of buoyancy via the Gulf Stream and compares them with the previous seven winters that exhibited more vigorous EDW formation. The weak 2011–2012 formation did not result from increased Gulf Stream heat advection, and was also not driven by preconditioning as the buoyancy content of the region prior to the onset of winter forcing was not unusually high. Rather, the weak formation resulted from climatologically weak surface cooling late in winter. The winter of 2007–2008 also experienced particularly weak EDW formation under similar conditions, including a high NAO and weak late winter surface cooling.
Sea state dependence of the wind stress over the ocean under hurricane winds
Authors: Reichl Brandon G. , Hara Tetsu , Ginis Isaac
Published: November 2013

The impact of the surface wave field (sea state) on the wind stress over the ocean is investigated with fetch‐dependent seas under uniform wind and with complex seas under idealized tropical cyclone winds. Two different approaches are employed to calculate the wind stress and the mean wind profile. The near‐peak frequency range of the surface wave field is simulated using the WAVEWATCH III model. The high‐frequency part of the surface wave field is empirically determined using a range of different tail levels. The results suggest that the drag coefficient magnitude is very sensitive to the spectral tail level but is not as sensitive to the drag coefficient calculation methods. The drag coefficients at 40 m/s vary from
to
depending on the saturation level. The misalignment angle between the wind stress vector and the wind vector is sensitive to the stress calculation method used. In particular, if the cross‐wind swell is allowed to contribute to the wind stress, it tends to increase the misalignment angle. Our results predict enhanced sea state dependence of the drag coefficient for a fast moving tropical cyclone than for a slow moving storm or for simple fetch‐dependent seas. This may be attributed to swell that is significantly misaligned with local wind.
Colors of Jupiter's large anticyclones and the interaction of a Tropical Red Oval with the Great Red Spot in 2008
Authors: Sánchez‐Lavega A. , Legarreta J. , García‐Melendo E. , Hueso R. , Pérez‐Hoyos S. , Gómez‐Forrellad J. M. , Fletcher L. N. , Orton G. S. , Simon‐Miller A. , Chanover N. , Irwin P. , Tanga P. , Cecconi M.
Published: November 2013

The nature and mechanisms producing the chromophore agents that provide color to the upper clouds and hazes of the atmospheres of the giant planets are largely unknown. In recent times, the changes in red coloration that have occurred in large‐ and medium‐scale Jovian anticyclones have been particularly interesting. In late June and early July 2008, a particularly color intense tropical red oval interacted with the Great Red Spot (GRS) leading to the destruction of the tropical red oval and cloud dispersion. We present a detailed study of the tropical vortices, usually white but sometimes red, and a characterization of their color spectral signatures and dynamics. From the spectral reflectivity in methane bands we study their vertical cloud structure compared to that of the GRS and BA. Using two spectral indices we found a near correlation between anticyclones cloud top altitudes and red color. We present detailed observations of the interaction of the red oval with the GRS and model simulations of the phenomena that allow us to constrain the relative vertical extent of the vortices. We conclude that the vertical cloud structure, vertical extent, and dynamics of Jovian anticyclones are not the causes of their coloration. We propose that the red chromophore forms when background material (a compound or particles) is entrained by the vortex, transforming into red once inside the vortex due to internal conditions, exposure to ultraviolet radiation, or to the mixing of two chemical compounds that react inside the vortex, confined by a potential vorticity ring barrier.
A radiative transfer model to simulate light scattering in a compact granular medium using a Monte‒Carlo approach: Validation and first applications
Authors: Pilorget C. , Vincendon M. , Poulet F.
Published: November 2013

A new radiative transfer model to simulate light scattering in a compact granular medium using a Monte‒Carlo approach is presented. The physical and compositional properties of the sample can be specified at the grain scale, thus allowing to simulate different kinds of heterogeneties/mixtures within the sample. The radiative transfer is then calculated using a ray tracing approach between the grains, and probabilistic physical parameters such as a single scattering albedo and a phase function at the grain level. The reflectance and the albedo can be computed at different scales and for different geometries: from the grain scale to the sample one. The photometric behavior of the model is validated by comparing the bidirectional reflectance obtained for various media and geometries with the one of semi‒infinite multilayer models, and a few first applications are presented. This model will be used to refine our understanding of visible/NIR remote sensing data of planetary surfaces, as well as future measurements of hyperspectral microscopes which may be able to resolve spatial compositional heterogeneities within a given sample.
Tropospheric delay statistics measured by two site test interferometers at Goldstone, California
Authors: Morabito David D. , D'Addario Larry R. , Acosta Roberto J. , Nessel James A.
Published: November 2013

Site test interferometers (STIs) have been deployed at two locations within the NASA Deep Space Network tracking complex in Goldstone, California. An STI measures the difference of atmospheric delay fluctuations over a distance comparable to the separations of microwave antennas that could be combined as phased arrays for communication and navigation. The purpose of the Goldstone STIs is to assess the suitability of Goldstone as an uplink array site and to statistically characterize atmosphere‐induced phase delay fluctuations for application to future arrays. Each instrument consists of two ~1 m diameter antennas and associated electronics separated by ~200 m. The antennas continuously observe signals emitted by geostationary satellites and produce measurements of the phase difference between the received signals. The two locations at Goldstone are separated by 12.5 km and differ in elevation by 119 m. We find that their delay fluctuations are statistically similar but do not appear as shifted versions of each other, suggesting that the length scale for evolution of the turbulence pattern is shorter than the separation between instruments. We also find that the fluctuations are slightly weaker at the higher altitude site.
Thermal Degradation and Flammability Properties of Polypropylene Nanocomposite Using Organoclay‐graft‐poly(Ethylene Glycol Methacrylate Phosphate)
Authors: Alsharif Mohammad Ali , Zadhoush Ali , Mortazavi Sayed Majid
Published: November 2013

Phosphorus‐containing groups were grafted on organoclay using cold plasma technique, accompanied by polymerization of ethylene glycol methacrylate phosphate monomers. The obtained compound as a new flame retardant (FR) was added to isotactic polypropylene (iPP) to produce pigmented iPP nanocomposite using twin‐screw micro extruder. Characterization was carried out for the best dispersion and chemical structure using scanning electron microscope, X‐ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. Flammability and burning behavior of iPP nanocomposite were characterized by limiting oxygen index and mass loos cone calorimeter. Thermal properties were investigated by thermogravimetry and differential thermogravimetry. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21386; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21386
Studies on Gelling Characteristics of N‐Tertiary Butyl Acrylamide–Acrylic Acid Copolymer
Authors: Bera Rabin , Dey Ayan , Chakrabarty Debabrata
Published: November 2013

Organogel copolymers of N‐tertiary butyl acrylamide (in‐house synthesized) and acrylic acid were made by free radical polymerization using N,N′‐methylene bisacrylamide as cross‐linker and different proportions of the comonomers. N‐tertiary butyl acrylamide and the gels were characterized by spectroscopic analysis, swelling performances, morphological studies, and thermal analysis. Swelling performances of the different gels as a function of cross‐link density of the gels, dipole characteristic, structure, and chemical composition of solvent were studied. Swelling and deswelling kinetics of the gels in some suitable solvents were also studied. An attempt has been made to utilize the deswelling characteristic of the swelled gels in slow and sustained release of volatiles as required in fire starters/fire gels or fragrance release. Swelling of the gel was maximum with 2 mol% of cross‐linker beyond which, it decreased. It was also dependent on the H‐bonding ability, dipole characteristic, chemical structure, and viscosity of the solvent. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21387; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21387
Alternating Current Electrical Properties of Thin Films of Plasma Polymerized 1, 1, 3, 3‐Tetramethoxypropane
Authors: Afroze Tamanna , Bhuiyan A. H.
Published: November 2013

Plasma‐polymerized 1, 1, 3, 3‐tetramethoxy‐propane (PPTMP) thin films are prepared by using a capacitively coupled glow discharge reactor. The dielectric constant and the alternating current (AC) electrical conductivity of the PPTMP thin films are investigated in the frequency range from 30 to 104 Hz, and in the temperature range from 298 to 423 K. The AC electrical conduction mechanism in the PPTMP thin films is observed to be dominated by hopping of carriers between localized states. The trend of dielectric constant is to decrease slowly with the increasing frequency. The dielectric constant is weakly dependent on temperature (T). The dielectric loss tangent, tanδ decreases slightly with a broad minimum around 103 Hz and again increases with increasing frequency. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21394; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21394
Nano and Hybrid Composites Based on Poly(ethylene terephthalate): Blending and Characterization
Authors: Barbosa Carlos N. , Gonçalves Frederico , Viana Júlio C.
Published: November 2013

This study addresses the characterization of nano and hybrid poly(ethylene terephthalate) (PET)‐based composites obtained by injection molding process. The aim is to demonstrate the effect of adding various nanoclay amounts on the morphology and mechanical behavior of unreinforced and glass fiber (GF) reinforced PET matrices. Also, it addresses the possibility of preserving the mechanical response of the composites while decreasing the amount of GF. Nanocomposites were prepared by adding 0.5, 1.0, 3.0, and 5.0 wt% of montmorillonite to the unreinforced PET matrix; hybrid composites were also prepared by adding the aforementioned nanoclay amounts to the 20% GF reinforced PET (PET20). A 35% GF reinforced PET was used as a reference material for the mechanical properties comparison. X‐ray diffraction and transmission electron microscopy studies revealed that the characteristic (001) peak of the nanocomposite obtained by extrusion shifted to the lower angle region stating an intercalated structure. The subsequent injection molding process altered the morphological structure of the composites, reducing the basal distance for small loadings of nanoclays. Differential scanning calorimetry showed that the addition of nanoclay increases the degree of crystallinity and decreases the cold crystallization temperature of both PET systems. Full exfoliation of the nanoclay was not attained but the nanoparticles dispersion in combination with their intercalated morphology improved the mechanical properties of PET composites optimally for 1% of incorporation. The envisaged mechanical properties of PET20 were improved (initial modulus ↑22%, stress at yield ↑14%, and strain at break ↑4%) for the aforementioned optimal value of incorporation. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21397; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21397
Optimization of Synthesis Amounts of Polymers with Two Monomers by Different Methods Based on Response Surface Methodology
Authors: Tian Minglei , Park Haeun , Row Kyung Ho
Published: November 2013

To synthesize a monolithic polymer with two different monomers, 17‐run Box–Behnken design (BBD) and 20‐run central composite design (CCD) were investigated and optimized three factors (volume of monomer, cross‐link, and porogen). According to the variance of the fitted quadratic polynomial model, BBD was more suitable for the two monomers than CCD. The adjusted coefficient of determination (RAdj2) for the model (0.995 and 0.997 for the two monomers) as well as the probability (p < 0.0001) revealed high significance of the regression model. The following optimized synthesis conditions were suggested by the BBD method (0.54 mL of monomer, 2.93 mL of cross‐link, and 2.95 mL of porogen for methyl methacrylate (MAA); 0.55 mL of monomer, 2.98 mL of cross‐link, and 2.86 mL of porogen for 2‐hydroxyethyl methacrylate (2‐HEMA)). Finally, 5137.6 and 4789.9 mg of MAA and 2‐HEMA monomers were predicted, respectively. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2014, 33, 21405; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21405
Sacred populations of Cercopithecus sclateri: Analysis of apparent population increases from census counts
Authors: Baker Lynne R. , Tanimola Adebowale A. , Olubode Oluseun S.
Published: November 2013

The development of effective conservation and management actions for populations of wild species generally requires monitoring programs that provide reliable estimates of population size over time. Primate researchers have to date given more attention to evaluating techniques for monitoring primates in natural habitats compared to populations that occur in villages or urban areas. We conducted censuses to estimate the abundance and density of two sacred, village‐dwelling populations (Lagwa and Akpugoeze) of Sclater's monkey (Cercopithecus sclateri), a threatened species endemic to southeastern Nigeria, and compared these data to previous census results. We recorded population increases in both sites: a 66% increase over 4½ years in Lagwa (from 124 to 206 individuals) at an annual rate of 10.2%, and a 29% increase over 4 years in Akpugoeze (from 193 to 249 individuals) at an annual rate of 5.7%. Mean group size also increased in both sites. Density in Lagwa was 24.2 individuals/km2, and density in a core survey area of Akpugoeze was 36–38 individuals/km2. Our results may have been affected by monkey ranging and grouping patterns and improved detectability due to our revised census technique, which included secondary observers. With further work on methodology for censusing populations that occur in human‐settled environments, techniques can be refined and customized to individual sites for more accurate estimates. Our investigation of Sclater's monkey in Lagwa and Akpugoeze, two sites critical for conservation of the species, indicated that both of these populations have increased, and neither faces immediate risk of extirpation. Such population growth, while encouraging, will likely exacerbate human–monkey conflict and thus should be understood in terms of potential socioeconomic impacts. Am. J. Primatol. 76:303–312, 2014. © 2013 Wiley Periodicals, Inc.
Plasmonische Synthese von metallischen Nanostrukturen
Authors: Langille Mark R. , Personick Michelle L. , Mirkin Chad A.
Published: November 2013

Edelmetall‐Nanostrukturen können in gewünschter Zusammensetzung, Größe und Form und mit ebenso maßgeschneiderten Eigenschaften hergestellt werden. Ihre Anwendungsmöglichkeiten sind äußerst vielfältig und reichen von der Medizin bis zur Elektronik. Besonders interessant ist die Möglichkeit, für ihre Synthese Licht zu verwenden. Im Prinzip kann man mit einer Anregungswellenlänge, die von den Nanostrukturen absorbiert wird, das Wachstum der Partikel gezielt steuern und z. B. aus einer heterogenen Ausgangspopulation eine homogene Endpopulation von Nanopartikeln gewinnen. Das beste Beispiel dafür ist die Synthese von Metall‐Nanopartikeln durch chemische Reduktion von Ag+ durch Citrat unter Anregung von Oberflächenplasmonen durch Licht. Als erstes wurde entdeckt, dass sich mithilfe von sichtbarem Licht sphärische Ag‐Nanopartikel in trigonale Ag‐Prismen umwandeln lassen. Diese plasmonische Synthese wurde dann zu einer leistungsfähigen Technik weiterentwickelt, um Ag‐Partikel sowie zahlreiche dimetallische Au‐Ag‐Nanostrukturen mit definierten Morphologien herzustellen. Wir erörtern, welche physikalischen und chemischen Faktoren für die strukturelle Selektion ausschlaggebend sind. Aus den Studien zu den plasmonischen Reaktionen folgern wir dann, welche Überlegungen für das Design der Partikelform wichtig sind. Diese Grundlagen lassen sich auf alle Synthesemethoden für Edelmetall‐Nanokristalle übertragen.
A Reusable Unsupported Rhenium Nanocrystalline Catalyst for Acceptorless Dehydrogenation of Alcohols through γ‐C–H Activation
Authors: Yi Jing , Miller Jeffrey T. , Zemlyanov Dmitry Y. , Zhang Ruihong , Dietrich Paul J. , Ribeiro Fabio H. , Suslov Sergey , Abu‐Omar Mahdi M.
Published: November 2013

Rhenium nanocrystalline particles (Re NPs), of 2 nm size, were prepared from NH4ReO4 under mild conditions in neat alcohol. The unsupported Re NPs convert secondary and benzylic alcohols to ketones and aldehydes, respectively, through catalytic acceptorless dehydrogenation (AD). The oxidant‐ and acceptor‐free neat dehydrogenation of alcohols to obtain dihydrogen gas is a green and atom‐economical process for making carbonyl compounds. Secondary aliphatic alcohols give quantitative conversion and yield. Transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), Re K‐edge X‐ray absorption near‐edge structure (XANES), and X‐ray absorption fine structure (EXAFS) data confirmed the characterization of the Re NPs as metallic rhenium with surface oxidation to rhenium(IV) oxide (ReO2). Isotope labeling experiments revealed a novel γ‐CH activation mechanism for AD of alcohols.
Kombination von On‐Chip‐Synthese einer fokussierten kombinatorischen Bibliothek mit computergestützter Vorhersage der biologischen Aktivität enthüllt Imidazopyridine als GPCR‐Liganden
Authors: Reutlinger Michael , Rodrigues Tiago , Schneider Petra , Schneider Gisbert
Published: November 2013

Am Beispiel der Ugi‐Dreikomponentenreaktion stellen wir ein schnelles und effizientes Verfahren für die Kopplung von On‐Chip‐Mikroflusssynthesen mit einer neuen Methode zur Vorhersage biologischer Targets vor, um neue Liganden‐Protein‐Beziehungen zu entdecken. Wir konnten auf diese Weise eine GPCR‐modulierende, kombinatorisch zugängliche Verbindungsklasse identifizieren. Diese effizienten Liganden binden mit antagonistischen Eigenschaften an die humanen Adenosin‐A1/2B‐ und adrenergen α1A/B‐Rezeptoren. Die Integration von Mikrofluidiksystemen für die chemische Synthese mit computergestützten Targetvorhersagen ist ein vielversprechendes Verfahren zur raschen Erstellung fokussierter Substanzbibliotheken mit hohen Trefferraten.
Plasmon‐Mediated Syntheses of Metallic Nanostructures
Authors: Langille Mark R. , Personick Michelle L. , Mirkin Chad A.
Published: November 2013

The ability to prepare noble metal nanostructures of a desired composition, size, and shape enables their resulting properties to be exquisitely tailored, which has led to the use of these structures in numerous applications, ranging from medicine to electronics. The prospect of using light to guide nanoparticle reactions is extremely attractive since one can, in principle, regulate particle growth based on the ability of the nanostructures to absorb a specific excitation wavelength. Therefore, using the nature of light, one can generate a homogenous population of product nanoparticles from a heterogeneous starting population. The best example of this is afforded by plasmon‐mediated syntheses of metal nanoparticles, which use visible light irradiation and plasmon excitation to drive the chemical reduction of Ag+ by citrate. Since the initial discovery that Ag triangular prisms could be prepared by the photo‐induced conversion of Ag spherical nanoparticles, plasmon‐mediated synthesis has become a highly controllable technique for preparing a number of different Ag particles with tight control over shape, as well as a wide variety of Au‐Ag bimetallic nanostructures. We discuss the underlying physical and chemical factors that drive structural selection and conclude by outlining some of the important design considerations for controlling particle shape as learned through studies of plasmon‐mediated reactions, but applicable to all methods of noble metal nanocrystal synthesis.
Single‐Electron‐Transfer‐Induced Coupling of Arylzinc Reagents with Aryl and Alkenyl Halides
Authors: Shirakawa Eiji , Tamakuni Fumiko , Kusano Eugene , Uchiyama Nanase , Konagaya Wataru , Watabe Ryo , Hayashi Tamio
Published: November 2013

Arylzinc reagents, prepared from aryl halides/zinc powder or aryl Grignard reagents/zinc chloride, were found to undergo coupling with aryl and alkenyl halides without the aid of transition‐metal catalysis to give biaryls and styrene derivatives, respectively. In this context, we have already reported the corresponding reaction using aryl Grignard reagents instead of arylzinc reagents. Compared with the Grignard cross‐coupling, the present reaction features high functional‐group tolerance, whereby electrophilic groups such as alkoxycarbonyl and cyano groups are compatible as substituents on both the arylzinc reagents and the aryl halides. Aryl halides receive a single electron and thereby become activated as the corresponding anion radicals, which react with arylzinc reagents, thus leading to the cross‐coupling products.
Temporal changes in the taxonomic and functional diversity of fish communities in shallow Chinese lakes: the effects of river–lake connections and aquaculture
Authors: Cheng Lin , Blanchet Simon , Loot Géraldine , Villéger Sebastien , Zhang Tanglin , Lek Sovan , Lek‐Ang Sithan , Li Zhongjie
Published: November 2013

Habitat modification by humans has severe impacts on the biotic and abiotic components of freshwater ecosystems. In China, shallow lakes in the Yangtze River basin are facing major habitat modification owing to the loss of their natural connections with rivers and the development of aquaculture.

In this study, temporal data (ranging from 1970 to 2010) from a set of lakes (n = 8) were used to quantify the abiotic and biotic consequences (i.e. taxonomic and functional diversity of fish communities) of such human activities. There were significant abiotic changes that mainly occurred after the 1990s. Specifically, water transparency decreased and the total nitrogen content of the lakes increased considerably.

A trend (although not significant) was detected towards a decrease in fish species richness over the period studied. The taxonomic dissimilarity (i.e. beta‐diversity) among fish communities decreased significantly over the years, indicating a strong homogenization of the fauna across the lakes.

In addition, it was found that fish functional diversity has decreased in most lakes since the 1970s. In particular most migratory fish species with long life‐spans and large body size disappeared from the lakes, hence contributing substantially to the observed decrease in functional diversity.

Based on the findings, it is argued that both the abiotic and biotic integrity of the lakes were seriously affected after the lakes lost their connections to the rivers. It would therefore be helpful to reconnect the lakes to rivers with wise sluice‐gate management, and regulate fishery activities in those lakes to restore fish diversity.

Copyright © 2013 John Wiley & Sons, Ltd.
Tweeting biomedicine: An analysis of tweets and citations in the biomedical literature
Authors: Haustein Stefanie , Peters Isabella , Sugimoto Cassidy R. , Thelwall Mike , Larivière Vincent
Published: November 2013

Data collected by social media platforms have been introduced as new sources for indicators to help measure the impact of scholarly research in ways that are complementary to traditional citation analysis. Data generated from social media activities can be used to reflect broad types of impact. This article aims to provide systematic evidence about how often Twitter is used to disseminate information about journal articles in the biomedical sciences. The analysis is based on 1.4 million documents covered by both PubMed and Web of Science and published between 2010 and 2012. The number of tweets containing links to these documents was analyzed and compared to citations to evaluate the degree to which certain journals, disciplines, and specialties were represented on Twitter and how far tweets correlate with citation impact. With less than 10% of PubMed articles mentioned on Twitter, its uptake is low in general but differs between journals and specialties. Correlations between tweets and citations are low, implying that impact metrics based on tweets are different from those based on citations. A framework using the coverage of articles and the correlation between Twitter mentions and citations is proposed to facilitate the evaluation of novel social‐media‐based metrics.
New perspective for biorefining cereals
Authors: Abecassis Joel , de Vries Huug , Rouau Xavier
Published: November 2013

We present a novel approach for the valorization of cereals as major renewable resources for food, functional molecules, and materials as well as for bioenergy. We use a dual approach matching numerous production options (technology push) with the wide range of requested and needed end‐products in a bio‐based society (market pull or reversed engineering). The approach is based on the enlarged concept of biorefining, taking into account global and local requirements and trends. Hence, on one hand, it focuses on large‐scale, main stream production, thus following traditional supply chain methodologies with additional attention to the utilization of co‐ and by‐products (visualized as branches of a tree). On the other hand, it is centered on value‐added, small‐scale production of a wide range of cereal constituents for a wide range of end‐products (visualized as a complex network). In both cases, the innovation needs and research questions are highlighted in view of the diverse local and global challenges. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd
DNA methylation reprogramming in cancer: Does it act by re‐configuring the binding landscape of Polycomb repressive complexes?
Authors: Reddington James P. , Sproul Duncan , Meehan Richard R.
Published: November 2013

DNA methylation is a repressive epigenetic mark vital for normal development. Recent studies have uncovered an unexpected role for the DNA methylome in ensuring the correct targeting of the Polycomb repressive complexes throughout the genome. Here, we discuss the implications of these findings for cancer, where DNA methylation patterns are widely reprogrammed. We speculate that cancer‐associated reprogramming of the DNA methylome leads to an altered Polycomb binding landscape, influencing gene expression by multiple modes. As the Polycomb system is responsible for the regulation of genes with key roles in cell fate decisions and cell cycle regulation, DNA methylation induced Polycomb mis‐targeting could directly drive carcinogenesis and disease progression.

Editor's suggested further reading in BioEssays Unmasking risk loci: DNA methylation illuminates the biology of cancer predisposition Abstract