bluuebunny/crossref_metadata_2025 huggingface dataset:
Importancia de los hábitos de estudio en el rendimiento académico del adolescente: diferencias por género
Authors: Capdevila Seder Ana , Bellmunt Villalonga Héctor
Published: February 2017

Los hábitos de estudio juegan un papel fundamental en el desempeño académico, pero éstos no se miden únicamente por la cantidad de tiempo dedicado a estudiar, es más bien una cuestión de calidad del estudio. En el presente artículo se analizan en profundidad los hábitos de estudio de 203 adolescentes de 2º ciclo de ESO de centros públicos de Castellón de la Plana. Los
instrumentos utilizados son el cuestionario CHTE (Cuestionario de Hábitos y Técnicas de Estudio) y las calificaciones escolares. El objetivo es detectar qué aspectos de los hábitos de estudio se relacionan con el rendimiento académico, así como hallar diferencias por género. Aspectos como la
planificación del tiempo, la actitud o el lugar de estudio, se presentan como elementos importantes a tener en cuenta de cara a mejorar el rendimiento académico. Existen importantes diferencias por género, tanto en hábitos de estudio como en el rendimiento académico.
Experiencia de la clase inversa en didáctica de las lenguas extranjeras
Authors: Barreras Gómez María Asunción
Published: February 2017

Este artículo se centra en la aplicación del modelo de la clase inversa en la asignatura de didáctica de las lenguas extranjeras en la Universidad de La Rioja. Esta metodología invierte los modelos tradicionales en el proceso de enseñanza-aprendizaje, facilitando pautas de trabajo online desde
fuera de la clase. En el aula el profesor ayuda al alumno en la aplicación de esos contenidos y se puede centrar en las necesidades del alumno. Para ello se han utilizado varias herramientas como
Power Points, Youtube, aunque se destaca especialmente Wikis y Kahoot. Cuando se planteó esta metodología los alumnos parecieron un poco desorientados. Sin embargo, la experiencia ha resultado ser muy beneficiosa.
Acciones matemáticas de 0 a 3 años a partir de instalaciones artísticas
Authors: Alsina Ángel , León Noemí
Published: February 2017

En este estudio se analizan las acciones matemáticas que llevan a cabo niños de 0-3 años en instalaciones artísticas, considerados espacios estéticos que fomentan la participación y les ayuda a desarrollarse. Las instalaciones artísticas se han organizado en el mesoespacio, que requiere el movimiento del cuerpo para poder ser analizado de forma completa. Han participado 85 niños de uno a tres años que han llevado a cabo acciones en dos instalaciones artísticas diferentes. Los resultados muestran que los niños de menor edad realizan un número reducido de acciones matemáticas (vinculadas a las cualidades sensoriales y a las cantidades), pero a medida que van
creciendo, el número de acciones se incrementa y a la vez se diversifica en relación a todos los bloques de contenido (cualidades sensoriales, cantidades, posiciones y formas, atributos mesurables).
Prácticas y recursos de ocio en la adolescencia
Authors: Ricoy María-Carmen , Fernández-Rodríguez Jennifer
Published: February 2017

En general los adolescentes cuentan con muchos recursos y grandes facilidades para disfrutar del ocio, con todo su desarrollo no está exento de problemáticas. Por ello, el objetivo central de este estudio es analizar las actividades y recursos de ocio de los adolescentes, así como determinar los lugares y círculos a los que lo circunscriben. El trabajo presentado se
aborda desde un enfoque cualitativo. Para la recogida de información se utilizó la técnica del relato participando 95 adolescentes, de entre 13 y 17 años, que residen en el entorno urbano. Los resultados y conclusiones de la investigación ponen de manifiesto que desarrollan distintas
actividades saludables en su tiempo libre  a través de recursos variados. Cabe destacarla realización de prácticas de ocio deportivo, las asociadas con la música, así como las de tipo digital. Estas últimas se centran en ver la TV, chatear, navegar por la red y jugar con videojuegos; mientras el uso de las redes sociales adquiere una incidencia moderada. Por otra parte, es de resaltar que  muestran preferencia por las actividades llevadas a cabo en solitario y con el grupo de iguales, siendo reducidas las desarrolladas con la familia y en lugares cerrados. Los hábitos de ocio consumista no se revelan como abusivos.
Los grupos de innovación educativa en la Enseñanza de la Historia en España: Análisis póstumo de los resultados de la aplicación del método por descubrimiento y estado de la cuestión de los aprendizajes por descubrimiento
Authors: Sallés Tenas Neus , Santacana Mestre Joan
Published: February 2017

La investigación se ha centrado en describir los principales grupos de innovación educativa en la enseñanza de la historia desde el año 1975 hasta la década de los años noventa, en especial de aquellos métodos que se basaban en el uso de fuentes primarias y en metodologías por descubrimiento. Una vez identificados, el trabajo pretende conocer mediante métodos cualitativos, la percepción y los recuerdos de un grupo de alumnos que, en este periodo desarrollaron esta metodología, con la finalidad de deducir la eficacia de estas metodologías.
Evaluando la formación virtual en sensibilización ambiental para sectores profesionales
Authors: Martínez-Villar Alberto , Gutiérrez-Pérez José , Perales-Palacios F. Javier
Published: February 2017

En este trabajo se evalúa un programa de formación virtual (AULAVEA) centrado en la sensibilización ambiental de colectivos profesionales de sectores primarios diversos como cocina, albañilería y gestión de residuos, entre otros. En dicho curso participó una muestra internacional de estudiantes del ámbito iberoamericano seleccionados previamente. Tras una revisión
de los antecedentes en esta línea de investigación se describe la plataforma diseñada al efecto. Para la evaluación de la oferta formativa se utilizó un cuestionario centrado en dimensiones propias
de la evaluación de programas. El trabajo aporta una parrilla de criterios empíricos de evaluación de la calidad del modelo formativo e-learning. Los resultados evidencian un alto nivel de satisfacción con el curso implementado, consiguiendo capacitar para el desarrollo de competencias
ambientales, si bien se considera que incluye una excesiva densidad informativa. Se concluye planteando diversas acciones de mejora para iniciativas como esta.
Chemotherapy induces tumor immune evasion by upregulation of programmed cell death ligand 1 expression in bone marrow stromal cells
Authors: Yang Mengqi , Liu Panpan , Wang Kefeng , Glorieux Christophe , Hu Yumin , Wen Shijun , Jiang Wenqi , Huang Peng
Published: February 2017

Programmed cell death ligand 1 (PD‐L1) is a negative regulator of the immune response that enables tumor cells to escape T‐cell immunity. Although PD‐L1 expression in cancer cells has been extensively studied, the expression of PD‐L1 in stromal cells and its clinical significance remain largely unknown. Here, we show that bone marrow stromal cells express a low level of PD‐L1 and that this molecule is significantly upregulated by key drugs used in the treatment of lymphoma at clinically relevant concentrations. Mechanistically, chemotherapeutic drugs induce PD‐L1 expression in stromal cells through upregulation of granulocyte macrophage colony‐stimulating factor and activation of the extracellular signal‐regulated kinase (ERK) 1/2 signaling pathway. Suppression of ERK by a chemical inhibitor or genetic silencing of ERK2 expression prevents drug‐induced PD‐L1 expression. PD‐L1 expression is upregulated in the bone marrow stromal cells of mice treated with doxorubicin and in drug‐treated bone marrow specimens from lymphoma patients. Drug‐induced PD‐L1 expression in stromal cells can cause significant impairment of T‐cell functions. Overall, our study reveals a previously unrecognized mechanism by which chemotherapy induces tumor immune evasion by upregulation of PD‐L1 in bone marrow stromal cells, and provides new evidence for the combination of chemotherapy and anti‐PD‐L1/PD‐1 as an effective strategy for treatment of lymphoma and other cancers.
Long‐term and seasonal Caspian Sea level change from satellite gravity and altimeter measurements
Authors: Chen J. L. , Wilson C. R. , Tapley B. D. , Save H. , Cretaux Jean‐Francois
Published: February 2017

We examine recent Caspian Sea level change by using both satellite radar altimetry and satellite gravity data. The altimetry record for 2002–2015 shows a declining level at a rate that is approximately 20 times greater than the rate of global sea level rise. Seasonal fluctuations are also much larger than in the world oceans. With a clearly defined geographic region and dominant signal magnitude, variations in the sea level and associated mass changes provide an excellent way to compare various approaches for processing satellite gravity data. An altimeter time series derived from several successive satellite missions is compared with mass measurements inferred from Gravity Recovery and Climate Experiment (GRACE) data in the form of both spherical harmonic (SH) and mass concentration (mascon) solutions. After correcting for spatial leakage in GRACE SH estimates by constrained forward modeling and accounting for steric and terrestrial water processes, GRACE and altimeter observations are in complete agreement at seasonal and longer time scales, including linear trends. This demonstrates that removal of spatial leakage error in GRACE SH estimates is both possible and critical to improving their accuracy and spatial resolution. Excellent agreement between GRACE and altimeter estimates also provides confirmation of steric Caspian Sea level change estimates. GRACE mascon estimates (both the Jet Propulsion Laboratory (JPL) coastline resolution improvement version 2 solution and the Center for Space Research (CSR) regularized) are also affected by leakage error. After leakage corrections, both JPL and CSR mascon solutions also agree well with altimeter observations. However, accurate quantification of leakage bias in GRACE mascon solutions is a more challenging problem.
Long‐term impacts of ocean wave‐dependent roughness on global climate systems
Authors: Shimura Tomoya , Mori Nobuhito , Takemi Tetsuya , Mizuta Ryo
Published: February 2017

Ocean surface waves can play an active role in climate systems, but they are often ignored in Global Climate Models (GCMs). Wave‐dependent surface roughness was implemented within the Atmospheric GCM (MRI‐AGCM) using the spectral wave model WAVEWATCH III. Two types of wave‐dependent roughness, due to wave steepness and to wave age, were considered. Climate simulations with wave‐dependent roughness were compared to simulations with just wind speed‐dependent roughness. In climate simulation with wave steepness‐dependent roughness, the spatial distribution of roughness is correlated to that of swell dominance. In simulation with wave age‐dependent roughness, the spatial distribution of roughness is correlated to that of wind direction stationarity. Both simulations show reduced roughness in the tropics, which leads to an enhancement of surface wind speeds by up to 15%; these enhanced wind speeds are closer to observations compared with the baseline simulation with just wind speed‐dependent roughness. We find that the reduced roughness and the enhanced wind speeds in the tropics lead to significant changes in atmospheric circulation, as in Hadley circulation and precipitation. The characteristic responses of the Hadley circulation and precipitation to changing sea surface roughness are presented.
Sensitivity of U.S. summer precipitation to model resolution and convective parameterizations across gray zone resolutions
Authors: Gao Yang , Leung L. Ruby , Zhao Chun , Hagos Samson
Published: February 2017

Simulating summer precipitation is a significant challenge for climate models that rely on cumulus parameterizations to represent moist convection processes. Motivated by recent advances in computing that support very high‐resolution modeling, this study aims to systematically evaluate the effects of model resolution and convective parameterizations across the gray zone resolutions. Simulations using the Weather Research and Forecasting model were conducted at grid spacings of 36 km, 12 km, and 4 km for two summers over the conterminous U.S. The convection‐permitting simulations at 4 km grid spacing are most skillful in reproducing the observed precipitation spatial distributions and diurnal variability. Notable differences are found between simulations with the traditional Kain‐Fritsch (KF) and the scale‐aware Grell‐Freitas (GF) convection schemes, with the latter more skillful in capturing the nocturnal timing in the Great Plains and North American monsoon regions. The GF scheme also simulates a smoother transition from convective to large‐scale precipitation as resolution increases, resulting in reduced sensitivity to model resolution compared to the KF scheme. Nonhydrostatic dynamics has a positive impact on precipitation over complex terrain even at 12 km and 36 km grid spacings. With nudging of the winds toward observations, we show that the conspicuous warm biases in the Southern Great Plains are related to precipitation biases induced by large‐scale circulation biases, which are insensitive to model resolution. Overall, notable improvements in simulating summer rainfall and its diurnal variability through convection‐permitting modeling and scale‐aware parameterizations suggest promising venues for improving climate simulations of water cycle processes.
Electrical discharges in the overshooting tops of thunderstorms
Authors: MacGorman Donald R. , Elliott Matthew S. , DiGangi Elizabeth
Published: February 2017

Previous studies have found that the vertical distribution of sources of very high frequency (VHF) signals from discharges mapped by Lightning Mapping Arrays typically have a secondary maximum in a storm's overshooting top. Low rates of these sources tend to occur continually throughout the lifetime of the overshooting top (OT), rather than sources occurring in the episodic distinct flashes observed at lower altitudes. This study examines the evolution of the VHF OT signature (VHF OT, defined here as a sustained period of ≥4 VHF sources per minute per 200 m layer above a storm's level of neutral buoyancy (LNB)) relative to the evolution of radar reflectivity and IR imagery of overshooting tops in three supercell and two multicell storms. The VHF OT began before OTs were detected in IR satellite imagery of the supercell storms. No OT was observed in IR imagery for either multicell storm, but this lack may have been due to the spatial and temporal resolution of the current IR imager. The VHF OT began near the time the 18 or 30 dBZ echo top rose above the LNB and ended near the time it fell below the LNB. There were too few radar volume scans of OTs in the multicell storms for a correlation analysis. In the supercell storms, however, the maximum altitude of VHF sources typically was less than or equal to the altitude of 18 dBZ echo tops and was correlated with these echo tops (linear correlation coefficient ≥0.86) during the period of the VHF OT.
The occurrence of ice production in slightly supercooled Arctic stratiform clouds as observed by ground‐based remote sensors at the ARM NSA site
Authors: Zhang Damao , Wang Zhien , Luo Tao , Yin Yan , Flynn Connor
Published: February 2017

Ice particle formation in slightly supercooled stratiform clouds is not well documented or understood. In this study, 4 years of combined lidar depolarization and radar reflectivity (Ze) measurements are analyzed to distinguish between cold drizzle and ice crystal formations in slightly supercooled Arctic stratiform clouds over the Atmospheric Radiation Measurement Program Climate Research Facility North Slope of Alaska Utqiaġvik (“Barrow”) site. Ice particles are detected and statistically shown to be responsible for the strong precipitation in slightly supercooled Arctic stratiform clouds at cloud top temperatures as high as −4°C. For ice precipitating Arctic stratiform clouds, the lidar particulate linear depolarization ratio (δpar_lin) correlates well with radar Ze at each temperature range, but the δpar_lin‐Ze relationship varies with temperature ranges. In addition, lidar depolarization and radar Ze observations of ice generation characteristics in Arctic stratiform clouds are consistent with laboratory‐measured temperature‐dependent ice growth habits.
An efficient hybrid method for estimating clear‐sky surface downward longwave radiation from MODIS data
Authors: Cheng Jie , Liang Shunlin , Wang Wenhui , Guo Yamin
Published: February 2017

This paper proposes an efficient hybrid method for estimating 1 km instantaneous clear‐sky surface downward longwave radiation (LWDN) from Moderate Resolution Imaging Spectroradiometer (MODIS) thermal infrared observations and the MODIS near‐infrared column water vapor (CWV) data product. The LWDN was formulated as a nonlinear function of surface upwelling longwave radiation estimated from the MODIS top‐of‐atmosphere (TOA) radiance of channels 29, 31, and 32, as well as CWV and the MODIS TOA radiance of channel 29. Ground measurements collected at 62 globally distributed sites from six networks were used to develop and validate the proposed hybrid method. The validation results showed that the bias and root‐mean‐square error (RMSE) were 0.0597 W/m2 and 21.008 W/m2. These results demonstrate that the performance of our method is superior to that of other studies reported in the literature. The drawback of our method is that LWDN is overestimated over high‐elevation areas with extremely low CWV (<0.5 g/cm2) and underestimated over regions with tropical climates that have extremely high CWV. A power function relating LWDN to CWV was derived and used as a complementary method to address these circumstances. The overestimation was overcome, and the bias and RMSE decreased from 9.407 W/m2 and 23.919 W/m2 to −0.924 W/m2 and 19.895 W/m2. The underestimation was also alleviated.
Transient aspects of the Hadley circulation forced by an idealized off‐equatorial ITCZ
Authors: Gonzalez Alex O. , Mora Rojas Gabriela , Schubert Wayne H. , Taft Richard K.
Published: February 2017

This paper presents analytical solutions of large‐scale, zonally symmetric overturning circulations in the tropical free troposphere forced by transient diabatic heating in the off‐equatorial intertropical convergence zone (ITCZ). The dynamics are discussed in the context of the time‐dependent meridional circulation equation arising in an equatorial β‐plane model. The solutions of these differential equations contain terms for the slow, quasi‐balanced part of the response and terms for the transient, zonally symmetric, inertia‐gravity wave part of the response. When the off‐equatorial (north of the equator) ITCZ diabatic heating is switched on at various rates, both parts of the response reveal a basic asymmetry between the southern and northern hemispheres, with the southern hemisphere side containing most of the quasi‐balanced compensating subsidence and transient inertia‐gravity wave activity. The inertia‐gravity waves travel in wave packets that bounce off a spectrum of turning latitudes and are analyzed in the context of an average conservation law approach. These traveling wave packets cause the mass flux in the southern and northern Hadley cells to pulsate on timescales of about 1, 2, and 3 days for diabatic heating of the external, first internal, and second internal vertical modes, respectively. The spectral characteristics of the vertical motion in the ITCZ and subsidence regions are slightly more complicated and depend on ITCZ location.
Longitudinal relations between children's cognitive and affective theory of mind with reactive and proactive aggression
Authors: Austin Gina , Bondü Rebecca , Elsner Birgit
Published: February 2017

Aggression may be performed for different reasons, such as defending oneself (reactive aggression) or to reach egoistic aims (proactive aggression). It is a widely accepted notion that a lack of theory of mind (ToM) as a basic social competence should be linked to higher aggression, but findings on the developmental links between ToM and different functions of aggression have been inconsistent. One reason for this may be the failure of taking the bi‐dimensionality of both ToM (cognitive vs. affective) and aggression (reactive vs. proactive) into account. In addition, the direction of effect remains unclear because longitudinal studies examining the mutual influences of both constructs are rare. Because research on ToM has focused on the preschool years, little is known about its development in middle childhood. Therefore, the present study examined the bi‐directional developmental links of cognitive and affective ToM with reactive and proactive aggression in a longitudinal study in N = 232, 6‐ to 9‐year‐olds. Two points of measurement with a delay of about 1 year were conducted, and data were analyzed via cross‐lagged structural equation modeling (SEM), controlling for age, gender, and information processing. In general, early ToM predicted later functions of aggression, but not vice versa. Cognitive and affective ToM were inversely related to later reactive aggression, but only affective but not cognitive ToM was inversely related to later proactive aggression. These findings emphasize the importance of ToM for the occurrence of aggression and of taking the bi‐dimensionality of both constructs into account when investigating their developmental links across childhood.
“Sounds a Bit Crazy, But It Was Almost More Personal:” A Qualitative Study of Patient and Clinician Experiences of Physical Therapist–Prescribed Exercise For Knee Osteoarthritis Via Skype
Authors: Hinman R. S. , Nelligan R. K. , Bennell K. L. , Delany C.
Published: February 2017

Objective

To explore the experience of patients and physical therapists with Skype for exercise management of knee osteoarthritis (OA).

Methods

This was a qualitative study. The Donabedian model for quality assessment in health care (structure, process, and outcomes) informed semistructured individual interview questions. The study involved 12 purposively sampled patients with knee OA who received physical therapist–prescribed exercise over Skype, and all therapists (n = 8) who delivered the intervention in a clinical trial were interviewed about their experiences. Interviews were audio recorded and transcribed. Two investigators undertook coding and analysis using a thematic approach.

Results

Six themes arose from both patients and therapists. The themes were Structure: technology (easy to use, variable quality, set‐up assistance helpful) and patient convenience (time efficient, flexible, increased access); Process: empowerment to self‐manage (facilitated by home environment and therapists focusing on effective treatment) and positive therapeutic relationships (personal undivided attention from therapists, supportive friendly interactions); and Outcomes: satisfaction with care (satisfying, enjoyable, patients would recommend, therapists felt Skype more useful as adjunct to usual practice) and patient benefits (reduced pain, improved function, improved confidence and self‐efficacy). A seventh theme arose from therapists regarding process: adjusting routine treatment (need to modify habits, discomfort without hands‐on, supported by research environment).

Conclusion

Patients and physical therapists described mostly positive experiences using Skype as a service delivery model for physical therapist–supervised exercise management of moderate knee OA. Such a model is feasible and acceptable and has the potential to increase access to supervised exercise management for people with knee OA, either individually or in combination with traditional in‐clinic visits.
Serious Infection Rates Among Children With Systemic Lupus Erythematosus Enrolled in Medicaid
Authors: Hiraki Linda T. , Feldman Candace H. , Marty Francisco M. , Winkelmayer Wolfgang C. , Guan Hongshu , Costenbader Karen H.
Published: February 2017

Objective

To investigate the nationwide prevalence and incidence of serious infections among children with systemic lupus erythematosus (SLE) enrolled in Medicaid, the US health insurance program for low‐income patients.

Methods

From Medicaid claims (2000–2006) we identified children ages 5 to <18 years with SLE (≥3 International Classification of Diseases, Ninth Revision [ICD‐9] codes of 710.0, each >30 days apart) and lupus nephritis (LN; ≥2 ICD‐9 codes for kidney disease on/after SLE codes). From hospital discharge diagnoses, we identified infection subtypes (bacterial, fungal, and viral). We calculated incidence rates (IRs) per 100 person‐years, mortality rates, and hazard ratios adjusted for sociodemographic factors, medications, and preventive care.

Results

Among 3,500 children with identified SLE, 1,053 serious infections occurred over 10,108 person‐years; the IR was 10.42 per 100 person‐years (95% confidence interval [95% CI] 9.80–11.07) among all those with SLE and 17.65 per 100 person‐years (95% CI 16.29–19.09) among those with LN. Bacterial infections were most common (87%, of which 39% were bacterial pneumonias). In adjusted models, African Americans and American Indians had higher rates of infections compared with white children, and those with comorbidities or receiving corticosteroids had higher infection rates than those without. Males had lower rates of serious infections compared to females. The 30‐day postdischarge mortality rate was 4.4%.

Conclusion

Overall, hospitalized infections were very common in children with SLE, with bacterial pneumonia being the most common infection. Highest infection risks were among African American and American Indian children, those with LN, comorbidities, and those taking corticosteroids.
High‐Quality Epitaxial MgB2 Josephson Junctions Grown by Molecular Beam Epitaxy
Authors: Li Lin , Zhang Hui , Yang Yi‐Hang , Miao Guo‐Xing
Published: February 2017

Epitaxial MgB2 films are grown with molecular beam epitaxy (MBE) and optimized with the assistance of in situ reflection high‐energy electron diffraction (RHEED). The RHEED patterns clearly revealed the evolution of film structures with growth temperatures and Mg:B ratio, providing the most direct guidance on optimizing growth conditions. A threshold temperature is identified, below which excess Mg will physically condense into the film, and above which excess Mg vaporizes right away leading to a self‐limiting growth process for chemically‐bound MgB2 phases. Hetero‐epitaxial (0001)‐MgB2/(111)‐MgO/(0001)‐MgB2 stacks are deposited and fabricated into micro Josephson junctions, which revealed clear Fraunhofer patterns and Fiske steps, indicating superb materials quality.
Microstructure, Texture, and Mechanical Properties of Alternate α/β Mg–Li Composite Sheets Prepared by Accumulative Roll Bonding
Authors: Zhong Feng , Wang Tianzi , Wu Ruizhi , Hou Legan , Zhang Jinghuai , Li Xinlin , Zhang Milin , Dong Anping , Sun Baode
Published: February 2017

Mg–5Li–1Al sheet and Mg–12Li–1Al sheet are used to prepare α/β Mg–Li composite sheets with accumulative roll bonding (ARB). The microstructure, texture, and mechanical properties of the specimens are investigated. Results show that, Mg–5Li–1Al alloy and Mg–12Li–1Al alloy alternatively distribute with uniform deformations and a good continuity, during the ARB process. With the increase in ARB passes, the hardness values of α layer and β layer increase, and the strength of composite sheet first increases, then maintains in a stable range. During the initial several passes, the elongation decreases, and it increases again after five passes. As for the texture density, with the increase in ARB passes, it first increases, then decreases. In the interface areas between sheets, a cross shear zone exists.
Reversible Programing of Soft Matter with Reconfigurable Mechanical Properties
Authors: He Huimin , Cao Xiaodong , Dong Hua , Ma Ting , Payne Gregory F.
Published: February 2017

Biology uses various cross‐linking mechanisms to tailor material properties, and this is inspiring technological efforts to couple independent cross‐linking mechanisms to create hydrogels with complex mechanical properties. Here, it is reported that a hydrogel formed from a single polysaccharide can be triggered to reversibly switch cross‐linking mechanisms and switch between elastic and viscoelastic properties. Specifically, the pH‐responsive self‐assembling aminopolysaccharide chitosan is used. Under acidic conditions, chitosan is polycationic and can be electrostatically cross‐linked by sodium dodecyl sulfate (SDS) micelles to confer viscoelastic and self‐healing properties. Under basic conditions, chitosan becomes neutral, the electrostatic SDS–chitosan interactions are no longer operative, and chitosan chains can self‐assemble to form crystalline network junctions that serve as strong physical cross‐links that confer elastic properties. Mechanical measurements performed in water demonstrate these different mechanical behaviors and the repeated pH‐induced switching between these behaviors. Printing of SDS micelles onto a neutral chitosan film allows the cross‐linking mechanisms to be spatially programed to confer anisotropic mechanical properties. The reversibility of these cross‐linking mechanisms allows the patterned films to be erased and reprogramed with reconfigured mechanical properties. Potentially, the ability to reversibly program hydrogel networks enables fabrication of the dynamically reconfigurable networks required for soft machines.
Electrical Differentiation of Mesenchymal Stem Cells into Schwann‐Cell‐Like Phenotypes Using Inkjet‐Printed Graphene Circuits
Authors: Das Suprem R. , Uz Metin , Ding Shaowei , Lentner Matthew T. , Hondred John A. , Cargill Allison A. , Sakaguchi Donald S. , Mallapragada Surya , Claussen Jonathan C.
Published: February 2017

Graphene‐based materials (GBMs) have displayed tremendous promise for use as neurointerfacial substrates as they enable favorable adhesion, growth, proliferation, spreading, and migration of immobilized cells. This study reports the first case of the differentiation of mesenchymal stem cells (MSCs) into Schwann cell (SC)‐like phenotypes through the application of electrical stimuli from a graphene‐based electrode. Electrical differentiation of MSCs into SC‐like phenotypes is carried out on a flexible, inkjet‐printed graphene interdigitated electrode (IDE) circuit that is made highly conductive (sheet resistance < 1 kΩ/sq) via a postprint pulse‐laser annealing process. MSCs immobilized on the graphene printed IDEs and electrically stimulated/treated (etMSCs) display significant enhanced cellular differentiation and paracrine activity above conventional chemical treatment strategies [≈85% of the etMSCs differentiated into SC‐like phenotypes with ≈80 ng mL−1 of nerve growth factor (NGF) secretion vs. 75% and ≈55 ng mL−1 for chemically treated MSCs (ctMSCs)]. These results help pave the way for in vivo peripheral nerve regeneration where the flexible graphene electrodes could conform to the injury site and provide intimate electrical simulation for nerve cell regrowth.
Fully Printed Electrodes on Stretchable Textiles for Long‐Term Electrophysiology
Authors: Bihar Eloïse , Roberts Timothée , Ismailova Esma , Saadaoui Mohamed , Isik Mehmet , Sanchez‐Sanchez Ana , Mecerreyes David , Hervé Thierry , De Graaf Jozina B. , Malliaras George G.
Published: February 2017

Fully printed electrodes consisting of a conducting polymer and an ionic liquid gel are fabricated on a stretchable textile. They are shown to record cardiac activity while the wearer is moving and for long periods of time, paving the way for the development of low‐cost devices for continuous health monitoring.
Hyperspectral Nonlinear Optical Light Generation from a Monolithic GaN Microcavity
Authors: Butler Sween , Jiang Hongxing , Lin Jingyu , Neogi Arup
Published: February 2017

Localized spatial excitation of a single hexagonal GaN micropyramid with () facets formed by selective area growth is optimized for nonlinear optical light (NLO) generation due to second harmonic generation (SHG) and multiphoton luminescence (MPL). Multiphoton transition induced ultraviolet and yellow luminescence is observed for excitations above and below half bandgap energy. SHG and MPL observed for excitations below half the bandgap energy are superimposed to realize broadband emission in the UV–visible range. The light generation is optimized by controlling the cavity modes formed by the hexagonal facets and the tip enhanced effects from the pyramid. The MPL is optimum at the apex of the pyramid. The SHG is most efficient within the pyramid (≈4 µm above the base) due to the formation of spatially stable cavity modes within the cavity. The NLO interactions within the pyramid are optimized to realize microphotonic white light sources and coherent tunable UV–visible sources using spatially controlled excitation without any change in material parameters. At the bandgap of GaN, the resonant two‐photon emission dominates the nonlinear light generation process compared to the coherent SHG light generated within the cavity.
Polar Dynamics at a Functional Group Level: Infrared‐Visible Sum‐Frequency Generation Study on Polar Columnar Liquid Crystals
Authors: Araoka Fumito , Isoda Morio , Miyajima Daigo , Seo Inseon , Oh‐e Masahito , Aida Takuzo , Takezoe Hideo
Published: February 2017

Organic ferroelectrics (OFEs) are an attractive topic in material science because of their usefulness in modern technologies. There are a variety of OFEs that have been developed through various approaches using various materials. To further design and understand OFEs, it is essentially important to evaluate the dynamical behaviors of individual molecules during polarization switching. Although recent developments in theoretical calculations offer powerful tools to predict how molecules assemble into complex structures at the molecular level, it is still too difficult to determine the dynamics in response to external stimuli at the functional group level. Here, this study adopts infrared‐visible sum‐frequency generation (IV‐SFG) to probe the electric‐field‐induced dynamics at the functional group level and reports on the switching mechanism of the bulk ferroelectricity and paraelectricity in an organic system for the first time. This paper demonstrates an IV‐SFG study on a recently‐discovered polar columnar liquid crystal system of tapered‐paraffinic‐wedge molecules, whose favorable wet‐processability may provide a suitable design for “paintable” organic ferroelectrics. Dynamic motions of dipoles, such as of phthalonitriles and amides, are successfully probed. In ferroelectric compounds, the phthalonitriles are responsible both for the ferroelectric and paraelectric switching, whereas the amides only for the ferroelectric switching.
A Flexible PMN‐PT Ribbon‐Based Piezoelectric‐Pyroelectric Hybrid Generator for Human‐Activity Energy Harvesting and Monitoring
Authors: Chen Yan , Zhang Yang , Yuan Feifei , Ding Fei , Schmidt Oliver G.
Published: February 2017

The rapid advancements of wearable electronics require continued innovation in sustainable power sources and human interactive sensors. An abundance of energy in various forms, such as mechanical, thermal, optical, and sound, are ubiquitous in the environment and human activities. Hybrid generators using piezoelectric polymers with relatively low piezoelectric and pyroelectric constants have been fabricated to simultaneously scavenge mechanical and thermal energies. In this work, micropatterned single‐crystal (1−x)Pb(Mg,Nb)O3‐xPbTiO3 (PMN‐PT) ribbons, which possess excellent piezoelectric and pyroelectric properties, are utilized to build human activities energy harvesting and monitoring systems. The flexible PMN‐PT ribbon‐based sensor conformally attached on the surface of human skin enables high sensitivity for human body motions and can detect acoustic sounds precisely. The sensor has been used for monitoring temperature‐related activities, caused for instance by warm water flow and even light illumination. The multifunctional performance of the PMN‐PT ribbon‐based hybrid generator shows great potential for self‐powered wearable and human activities monitoring devices.
Determinants and outcomes of upfront surgery versus medical therapy for chronic rhinosinusitis in cystic fibrosis
Authors: Ayoub Noel , Thamboo Andrew , Habib Al‐Rahim , Nayak Jayakar V. , Hwang Peter H.
Published: February 2017

Background

The indications for surgical management of chronic rhinosinusitis (CRS) in patients with cystic fibrosis (CF) are poorly defined. In this study we compare outcomes of medical versus surgical treatment and examine trends associated with the transition from medical to surgical therapy in CF patients.

Methods

One hundred thirty‐six patients with CF referred to a tertiary rhinology practice were retrospectively divided into 3 cohorts: Medical, Upfront Surgery, or Crossover, if they converted from medical to surgical management. The 22‐item Sino‐Nasal Outcome Test (SNOT‐22) and pulmonary function test (PFT) data were assessed up to 48 months.

Results

Compared to patients initially managed medically (n = 90), those who pursued upfront surgery (n = 46) had a greater incidence of nasal polyposis (p = 0.0011), prior sinus surgery (p = 0.0025), lower percent‐predicted forced expiratory volume in 1 second (%FEV1) (p = 0.0063), and higher Lund‐Mackay (p = 0.0025) and SNOT‐22 (p = 0.0229) scores. Within the medical group, 35.5% converted to surgery after a mean of 14.3 months. Crossover (n = 32) was associated with a 6.1‐point increase in SNOT‐22 and a 4.5% deterioration in %FEV1. Despite worsened symptom severity, the Crossover cohort ultimately achieved similar postoperative SNOT‐22 scores (p = 0.831) and %FEV1 (p = 0.114) as those who underwent upfront surgery. Although the Medical cohort had the lowest baseline SNOT‐22 scores (p < 0.001), surgery at any time normalized scores to the same baseline level (p = 0.652). Neither medical therapy nor surgery improved PFTs.

Conclusions

Surgery effectively reduces CRS‐related symptoms in CF patients but may not improve pulmonary function. In patients who first pursue medical therapy, symptomatic decline may prompt eventual conversion to surgery. Patients who delay surgery may achieve similar outcomes as those who pursue surgery upfront.
Active and recyclable ordered mesoporous magnetic organometallic catalyst as high‐performance visible light photocatalyst for degradation of organic pollutants
Authors: Nejat Razieh , Chamack Masoumeh , Mahjoub Alireza
Published: February 2017

A novel light‐active magnetic Pd complex as a photocatalyst was prepared through bonding organometallics to mesoporous silica channels formed on the surface of silica‐coated iron oxide nanoparticles. The nanocomposite (denoted as Fe3O4@SiO2@m‐SiO2@PDA‐Pd(0); PDA = 1,10‐phenanthroline‐2,9‐dicarbaldehyde) is more efficient and has higher photocatalytic capability in the degradation of 2,4‐dichlorophenol under visible light irradiation compared with virgin Pd complex (PDA‐Pd). This noteworthy photodegradation activity can be due to the high dispersion of Pd nanoparticles. High yield, low reaction time and non‐toxicity of the catalyst are the main merits of this protocol. Also magnetic separation is an environmentally friendly alternative method for the separation and recovery of the catalyst, since it minimizes the use of solvents and auxiliary materials, reduces operation time and minimizes catalyst loss by preventing mass loss and oxidation. The produced Pd catalyst was characterised using various techniques. Furthermore, transmission electron microscopy characterization was used for determining the structural properties of the Pd nanocatalyst.
Thermo‐oxidative stabilization of poly(lactic acid)‐based nanocomposites through the incorporation of clay with in‐built antioxidant activity
Authors: Dintcheva Nadka Tzankova , Al‐Malaika Sahar , Morici Elisabetta , Arrigo Rossella
Published: February 2017

In this work, an innovative approach to overcome the issue of the poor thermo‐oxidative stability of polymer/clay nanocomposites is proposed. Specifically, biodegradable poly(lactic acid) (PLA)‐based nanocomposites, containing organo‐modified clay with in‐built antioxidant activity, were prepared. Through a two‐step chemical protocol, a hindered phenol antioxidant was chemically linked to the ammonium quaternary salt which was then intercalated between the clay platelets [(AO)OM‐Mt]. The nanocomposites were characterized and their thermo‐oxidative stability during melt processing and under long‐term thermal test conditions was investigated. PLA nanocomposites containing the (AO)OM‐Mt showed higher oxidative stability, along with better clay dispersion, compared to PLA‐nanocomposites containing commercial clay and a free hindered phenol antioxidant. Obtained results can be explained considering that (AO)OM‐Mt may act locally, at the interface, between the silicate layers and the polymer macromolecules, thus contributing to the observed improved stability of the polymer both during processing and under long‐term thermal‐oxidative conditions. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44974.
Serum Urate Levels Predict Joint Space Narrowing in Non‐Gout Patients With Medial Knee Osteoarthritis
Authors: Krasnokutsky Svetlana , Oshinsky Charles , Attur Mukundan , Ma Sisi , Zhou Hua , Zheng Fangfei , Chen Meng , Patel Jyoti , Samuels Jonathan , Pike Virginia C. , Regatte Ravinder , Bencardino Jenny , Rybak Leon , Abramson Steven , Pillinger Michael H.
Published: February 2017

Objective

The pathogenesis of osteoarthritis (OA) includes both mechanical and inflammatory features. Studies have implicated synovial fluid uric acid (UA) as a potential OA biomarker, possibly reflecting chondrocyte damage. Whether serum UA levels reflect/contribute to OA is unknown. We investigated whether serum UA levels predict OA progression in a non‐gout knee OA population.

Methods

Eighty‐eight patients with medial knee OA (body mass index [BMI] <33 kg/m2) but without gout were studied. Baseline serum UA levels were measured in previously banked serum samples. At 0 and 24 months, patients underwent standardized weight‐bearing fixed‐flexion posteroanterior knee radiography to determine joint space width (JSW) and Kellgren/Lawrence grades. Joint space narrowing (JSN) was calculated as the change in JSW from 0 to 24 months. Twenty‐seven patients underwent baseline contrast‐enhanced 3T knee magnetic resonance imaging for assessment of synovial volume.

Results

Serum UA levels correlated with JSN values in both univariate (r = 0.40, P < 0.01) and multivariate (r = 0.28, P = 0.01) analyses. There was a significant difference in mean JSN after dichotomization at a serum UA cut point of 6.8 mg/dl, the solubility point for serum urate, even after adjustment (JSN of 0.90 mm for a serum UA ≥6.8 mg/dl and 0.31 mm for a serum UA <6.8 mg/dl; P < 0.01). Baseline serum UA levels distinguished progressors (JSN >0.2 mm) and fast progressors (JSN >0.5 mm) from nonprogressors (JSN ≤0.0 mm) in multivariate analyses (area under the receiver operating characteristic curve 0.63 [P = 0.03] and 0.62 [P = 0.05], respectively). Serum UA levels correlated with the synovial volume (r = 0.44, P < 0.01), a possible marker of JSN, although this correlation did not persist after controlling for age, sex, and BMI (r = 0.13, P = 0.56).

Conclusion

In non‐gout patients with knee OA, the serum UA level predicted future JSN and may serve as a biomarker for OA progression.
Secukinumab in Active Rheumatoid Arthritis: A Phase III Randomized, Double‐Blind, Active Comparator– and Placebo‐Controlled Study
Authors: Blanco Francisco J. , Möricke Rüdiger , Dokoupilova Eva , Codding Christine , Neal Jeffrey , Andersson Mats , Rohrer Susanne , Richards Hanno
Published: February 2017

Objective

To evaluate the efficacy and safety of secukinumab in patients with active rheumatoid arthritis (RA) who had an inadequate response to or intolerance of tumor necrosis factor (TNF) inhibitors.

Methods

In this phase III study, 551 patients were randomized (1:1:1:1) to receive intravenous secukinumab at a dose of 10 mg/kg (at baseline and weeks 2 and 4) followed by subcutaneous secukinumab at a dose of either 150 mg or 75 mg every 4 weeks or, alternatively, abatacept or placebo on the same dosing schedule. The primary end point was the proportion of patients achieving 20% improvement in disease activity according to the American College of Rheumatology response criteria (ACR20) at week 24 in the secukinumab 150 mg or 75 mg treatment groups as compared with placebo. Key secondary end points included change from baseline to week 24 in the Disease Activity Score in 28 joints using C‐reactive protein level (DAS28‐CRP) and the Health Assessment Questionnaire disability index (HAQ DI), as well as the ACR 50% improvement (ACR50) response rate at week 24.

Results

The primary efficacy end point was met in patients receiving 150 mg secukinumab, in whom the ACR20 response rate at week 24 was significantly higher than that in the placebo group. The ACR20 response rates at week 24 were 30.7% in patients receiving 150 mg secukinumab (P = 0.0305), 28.3% in those receiving 75 mg secukinumab (P = 0.0916), and 42.8% in those receiving abatacept, compared with 18.1% in the placebo group. A significant reduction in the DAS28‐CRP was seen in patients treated with 150 mg secukinumab (P = 0.0495), but not in patients treated with 75 mg secukinumab. Improvements in the HAQ DI and ACR50 response rates were not significant in the 2 secukinumab dose groups compared with the placebo group. The overall safety profile was similar across all treatment groups.

Conclusion

Secukinumab at a dose of 150 mg resulted in improvement in signs and symptoms and reduced disease activity in patients with active RA who had an inadequate response to TNF inhibitors. Improvements observed with abatacept were numerically higher than with secukinumab. There were no new or unexpected safety signals with secukinumab in this study.
How do ADARs bind RNA? New protein‐RNA structures illuminate substrate recognition by the RNA editing ADARs
Authors: Thomas Justin M. , Beal Peter A.
Published: February 2017

Deamination of adenosine in RNA to form inosine has wide ranging consequences on RNA function including amino acid substitution to give proteins not encoded in the genome. What determines which adenosines in an mRNA are subject to this modification reaction? The answer lies in an understanding of the mechanism and substrate recognition properties of adenosine deaminases that act on RNA (ADARs). Our recent publication of X‐ray crystal structures of the human ADAR2 deaminase domain bound to RNA editing substrates shed considerable light on how the catalytic domains of these enzymes bind RNA and promote adenosine deamination. Here we review in detail the deaminase domain‐RNA contact surfaces and present models of how full length ADARs, bearing double stranded RNA‐binding domains (dsRBDs) and deaminase domains, could process naturally occurring substrate RNAs.