bluuebunny/crossref_metadata_2025 huggingface dataset:
Urinalysis as a diagnostic tool in severe malaria
Authors: Barrera Sebastián , Tobón-Castaño Alberto
Published: January 2018

La malaria produce complicaciones y muerte especialmente en poblaciones con acceso limitado a la atención en salud. La malaria grave puede reconocerse tempranamente mediante la detección en la orina de hallazgos como la hematuria, la coluria y la proteinuria.Se hizo una revisión narrativa basada en estudios sobre malaria grave y el empleo del análisis de orina mediante la consulta de 91 publicaciones.Mediante el análisis de la orina, se pueden detectar alteraciones metabólicas y lesiones en distintos órganos. En estudios recientes en Colombia se ha confirmado su utilidad como apoyo en el diagnóstico de la disfunción renal, la disfunción hepática y la anemia asociada con hemólisis, las cuales son complicaciones frecuentes en la malaria.El examen constituye una herramienta de fácil aplicación en la consulta ambulatoria y en pacientes hospitalizados para reconocer tempranamente casos complicados, y permite la detección oportuna de diferentes lesiones en el paciente con malaria, contribuyendo así a la reducción de la morbilidad grave y la mortalidad.
Results of the national surveillance of antimicrobial resistance of Enterobacteriaceae and Gram negative bacilli in health care-associated infections in Colombia, 2012-2014
Authors: Ovalle María Victoria , Saavedra Sandra Yamile , González María Nilse , Hidalgo Andrea Melissa , Duarte Carolina , Beltrán Mauricio
Published: January 2018

Introducción. En el tercer trimestre de 2012, comenzó a operar el Sistema Nacional de Vigilancia de Resistencia Antimicrobiana en las infecciones asociadas a la atención en salud, con el fin de recabar y analizar la información referente al problema en Colombia.Objetivo. Describir los perfiles de resistencia y los resultados de la vigilancia por el laboratorio con base en los datos recolectados en el Sistema.Materiales y métodos. Se hizo un estudio descriptivo y retrospectivo con base en la información del Sistema Nacional de Vigilancia en Salud Pública, Sivigila, 1 de septiembre de 2012 a 31 de diciembre de 2014, así como de las bases de datos Whonet con los datos notificados por las unidades primarias generadoras de datos y los resultados de la confirmación por el laboratorio de la caracterización fenotípica y genotípica de la resistencia a carbapenemasas en 1.642 aislamientos (927 de enterobacterias, 614 de Pseudomonas spp. y 101 de Acinetobacter spp.).Resultados. La resistencia de Escherichia coli a las cefalosporinas de tercera generación presentó un incremento significativo, alcanzando 26,3 % en unidades de cuidados intensivos y 22,5 % en otras áreas de hospitalización. La resistencia a ertapenem de Klebsiella pneumoniae registró un incremento y alcanzó 14,6 % en unidades de cuidados intensivos. La resistencia de Acinetobacter baumannii a los carbapenémicos superó el 50 % en dichas unidades, en tanto que en Pseudomonas aeruginosa se presentaron porcentajes más bajos (38,8 %). Las carbapenemasas más frecuentes en enterobacterias fueron la KPC (n=574), seguida de la NDM (n=57); en P. aeruginosa, la VIM (n=229) y la KPC (n=114), y en A. baumannii, la OXA-23 (n=87). Se detectaron varias combinaciones de carbapenemasas, siendo la de KPC y VIM la más frecuente en Pseudomonas spp., y en enterobacterias.Conclusión. La información obtenida a partir del Sistema Nacional de Vigilancia ha permitido conocer los perfiles y los mecanismos de resistencia a carbapenémicos de las cepas que están circulando en las instituciones de salud del país.
In vitro susceptibility of Cuban Aspergillus spp. strains of clinical and environmental origin
Authors: San Juan Javier L. , Fernández Carlos M. , Almaguer Michel , Perurena Mayda R. , Martínez Gerardo F. , Velar Rosario E. , Illnait María T.
Published: January 2018

Introducción. En Cuba se desconoce el comportamiento de la sensibilidad de Aspergillus spp. a los antifúngicos recomendados para el tratamiento de la aspergilosis: la anfotericina B, el itraconazol, el voriconazol y las equinocandinas. La influencia del ambiente puede condicionar la aparición de resistencia en estos microorganismos.Objetivo. Evaluar la sensibilidad in vitro de cepas de Aspergillus spp. a la anfotericina B, el itraconazol y el voriconazol, y la relación de los patrones de sensibilidad con su origen.Materiales y métodos. Se determinaron las concentraciones inhibitorias mínimas de la anfotericina B, el itraconazol y el voriconazol para 60 cepas de Aspergillus spp. de origen clínico y ambiental mediante el método M38-A2 del Clinical and Laboratory Standard Institute.Resultados. Se encontraron 21 cepas resistentes a la anfotericina B (principalmente en muestras clínicas y ambientes hospitalarios) y tres cepas resistentes al itraconazol (en ambientes interiores y exteriores no hospitalarios). No se hallaron cepas resistentes al voriconazol. No se encontró relación entre el origen de las cepas y su sensibilidad.Conclusiones. Se sugiere la posible existencia de factores ambientales o interacciones con genotipos resistentes que pueden dar origen a fenotipos resistentes en Cuba. Este es el primer reporte del país de cepas de Aspergillus spp. resistentes in vitro. Los resultados ameritan ampliar el estudio para incluir análisis moleculares y filogenéticos.
Wernicke-Korsakoff syndrome secondary to cytomegalovirus encephalitis: A case report
Authors: Uribe Luis Guillermo , Pérez María Alejandra , Lara Camilo Andrés , Rueda Natalia , Hernández Javier Augusto
Published: January 2018

El citomegalovirus (CMV) es uno de los microorganismos oportunistas con mayor prevalencia en pacientes inmunocomprometidos, aunque su reactivación ha descendido después de la introducción de la terapia antirretroviral altamente activa (Highly Active Antiretroviral Therapy, HAART). En las coinfecciones, la encefalitis se ha reportado como una de las condiciones más frecuentes.Se presenta el caso de un paciente adulto joven con infección por virus de la inmunodeficiencia humana (HIV) que tuvo un rápido deterioro neurológico evidenciado en síntomas y signos clínicos clásicos del síndrome de Wernicke-Korsakoff y que no presentaba factores de riesgo para deficiencia de tiamina. En las imágenes de la resonancia magnética cerebral, se detectaron hallazgos típicos del síndrome, y se identificó citomegalovirus (CMV) en el líquido cefalorraquídeo. Con el tratamiento específico para el CMV, se logró el control de los síntomas, aunque hubo secuelas neurológicas que mejoraron.Este es uno de los pocos casos reportados a nivel mundial de síndrome de Wernicke secundario a encefalitis por citomegalovirus.
Validation of an analytical methodology to determine polychlorinated biphenyls in samples from blood plasma
Authors: Ávila Boris Santiago , Ramírez Carolina
Published: January 2018

Introducción. Los bifenilos policlorados se encuentran entre los cinco contaminantes orgánicos persistentes más tóxicos para los organismos vivos, según la Agency for Toxic Substances and Disease Registry (ATSDR) de los Estados Unidos.Objetivo. Estandarizar y validar un método analítico para la determinación y cuantificación de los bifenilos policlorados indicadores en muestras de plasma sanguíneo, mediante cromatografía de gases acoplada a espectrometría de masas.Materiales y métodos. Se fortificó un pool de plasma para hacer los ensayos en la matriz. Además, se utilizó el material de referencia NIST SRM® 1958 (Organic Contaminants in Fortified Human Serum, Freeze-Dried) para los ensayos de veracidad y precisión intermedia.Resultados. Los porcentajes de recuperación obtenidos con la metodología estuvieron entre 88,4 y 97,5 %, y el sesgo fue menor del 20 %. Los límites de detección y cuantificación de los bifenilos policlorados indicadores policlorados fueron de 0,04 μg/L y 0,10 μg/L, respectivamente. La linealidad representada por el coeficiente de determinación (R2) varió entre 0,9866 y 0,9886. La precisión expresada como desviación estándar relativa fue menor del 20 % en todo el rango lineal de trabajo (0,5-500 μg/L). Por último, se analizaron 115 muestras de población colombiana de diferentes zonas del país y se encontraron 65 muestras positivas, de las cuales dos estuvieron por encima de los valores de control biológico en humanos (Human Biomonitoring Values, HBM- II): 7,0 μg/L, 2XΣPCB 138, 153, 180, y otras dos, por encima del HBM-I: 3,5 μg/L, 2XΣPCB 138, 153, 180.Conclusión. El método desarrollado resultó ser preciso para el análisis de los bifenilos policlorados en muestras de plasma sanguíneo y se puede utilizar para el control biológico de estos contaminantes en población colombiana.
Curvas de fusión de regiones genómicas específicas: una herramienta prometedora para el diagnóstico y tipificación de las especies causantes de la leishmaniasis cutánea en Colombia
Authors: Marin Johana , Urrea Daniel , Muskus Carlos , Echeverry María Clara , Mejía Ana María , Triana Omar
Published: January 2018

Introducción. La leishmaniasis cutánea es una enfermedad causada por parásitos del género Leishmania que tiene gran incidencia en Colombia. El diagnóstico y la identificación de la especie infecciosa son factores críticos en el momento de escoger e iniciar el tratamiento. Actualmente, los métodos de diagnóstico y tipificación requieren procedimientos complejos, por lo que es necesario validar nuevos marcadores moleculares y métodos que simplifiquen el proceso.Objetivo. Desarrollar una herramienta basada en la reacción en cadena de la polimerasa (PCR) con curvas de fusión (High Resolution Melting; PCR-HRM) para el diagnóstico y tipificación de las tres especies de Leishmania de importancia epidemiológica en casos de leishmaniasis cutánea en Colombia.Materiales y métodos. Los genomas de Leishmania panamensis, L. braziliensis y L. guyanensis se compararon mediante métodos bioinformáticos. Las regiones específicas de especie identificadas se validaron mediante PCR. Para los marcadores seleccionados se diseñó una PCR-HRM y se estimaron algunos parámetros de validez y seguridad usando aislamientos de pacientes colombianos caracterizados previamente mediante PCR y análisis de polimorfismos en la longitud de los fragmentos de restricción (Restriction Fragment Length Polymorphism – RFLP; PCR-RFLP) del gen hsp70.Resultados. El análisis genómico comparativo mostró 24 regiones específicas de especie. Sin embargo, la validación mediante PCR solo identificó un marcador específico para cada especie de Leishmania. Los otros marcadores mostraron amplificación cruzada. El límite de detección para los tres marcadores seleccionados fue de un parásito, mientras que la sensibilidad, la especificidad, el valor predictivo positivo y el negativo fueron de 91,4, 100, 100 y 75 %, respectivamente.Conclusiones. Las tres regiones seleccionadas pueden emplearse como marcadores moleculares en el diagnóstico y tipificación de las especies causantes de la leishmaniasis cutánea en Colombia.
Establishment of an immortalized mouse dermal papilla cell strain with optimized culture strategy
Authors: Guo Haiying , Xing Yizhan , Zhang Yiming , He Long , Deng Fang , Ma Xiaogen , Li Yuhong
Published: January 2018

Dermal papilla (DP) plays important roles in hair follicle regeneration. Long-term culture of mouse DP cells can provide enough cells for research and application of DP cells. We optimized the culture strategy for DP cells from three dimensions: stepwise dissection, collagen I coating, and optimized culture medium. Based on the optimized culture strategy, we immortalized primary DP cells with SV40 large T antigen, and established several immortalized DP cell strains. By comparing molecular expression and morphologic characteristics with primary DP cells, we found one cell strain named iDP6 was similar with primary DP cells. Further identifications illustrate that iDP6 expresses FGF7 and α-SMA, and has activity of alkaline phosphatase. During the process of characterization of immortalized DP cell strains, we also found that cells in DP were heterogeneous. We successfully optimized culture strategy for DP cells, and established an immortalized DP cell strain suitable for research and application of DP cells.
Modeling Air Pollution, Climate, and Health Data Using Bayesian Networks: A Case Study of the English Regions
Authors: Vitolo Claudia , Scutari Marco , Ghalaieny Mohamed , Tucker Allan , Russell Andrew
Published: January 2018

The link between pollution and health is commonly explored by trying to identify the dominant cause of pollution and its most significant effect on health outcomes. The use of multivariate features to describe exposure is less explored because investigating a large domain of scenarios is theoretically (i.e., interpretation of results) and technically (i.e., computational effort) challenging. In this work we explore the use of Bayesian Networks with a multivariate approach to identify the probabilistic dependence structure of the environment‐health nexus. This consists of environmental factors (topography and climate), exposure levels (concentration of outdoor air pollutants), and health outcomes (mortality rates). The information is collated with regard to a data‐rich study area: the English regions (UK), which incorporate environmental types that are different in character from urban to rural. We implemented a reproducible workflow in the R programming language to collate environment‐health data and analyze almost 50 millions of observations making use of a graphical model (Bayesian Network) and Big Data technologies. Results show that for pollution and weather variables the model tests well in sample but also has good predictive power when tested out of sample. This is facilitated by a training/testing split in the data along time and space dimension and suggests that the model generalizes well to new regions and time periods.
Oxidative Processing Lowers the Ice Nucleation Activity of Birch and Alder Pollen
Authors: Gute Ellen , Abbatt Jonathan P. D.
Published: January 2018

Pollen carry water extractable compounds with ice nucleating (IN) activity. This study investigates whether the hydroxyl radical, as the major atmospheric oxidant, can affect the IN activity of silver birch and grey alder subpollen particles under in‐cloud conditions for deposition freezing mode conditions at 234 K. It is found that oxidation increases the supersaturation ratio with respect to ice necessary for the onset of ice nucleation and decreases the fraction of particles which initiate ice nucleation. This reduction of IN activity under equivalent oxidation conditions does not occur with a mineral dust sample (Arizona Test Dust). Chemical analysis of fresh and oxidized pollen material indicates a change of molecular structure with a loss of conjugation and an increase in oxidized functional groups, such as carbonyls. This is the first demonstration that in‐cloud oxidation may lower the IN abilities of biological particles such as pollen.
Geologic Inheritance and Earthquake Rupture Processes: The 1905 M ≥ 8 Tsetserleg‐Bulnay Strike‐Slip Earthquake Sequence, Mongolia
Authors: Choi Jin‐Hyuck , Klinger Yann , Ferry Matthieu , Ritz Jean‐François , Kurtz Robin , Rizza Magali , Bollinger Laurent , Davaasambuu Battogtokh , Tsend‐Ayush Nyambayar , Demberel Sodnomsambuu
Published: January 2018

In 1905, 14 days apart, two M ~ 8 continental strike‐slip earthquakes, the Tsetserleg and Bulnay earthquakes, occurred on the Bulnay fault system, in Mongolia. Together, they ruptured four individual faults, with a total length of ~676 km. Using submetric optical satellite images “Pleiades” with ground resolution of 0.5 m, complemented by field observation, we mapped in detail the entire surface rupture associated with this earthquake sequence. Surface rupture along the main Bulnay fault is ~388 km in length, striking nearly E‐W. The rupture is formed by a series of fault segments that are 29 km long on average, separated by geometric discontinuities. Although there is a difference of about 2 m in the average slip between the western and eastern parts of the Bulnay rupture, along‐fault slip variations are overall limited, resulting in a smooth slip distribution, except for local slip deficit at segment boundaries. We show that damage, including short branches and secondary faulting, associated with the rupture propagation, occurred significantly more often along the western part of the Bulnay rupture, while the eastern part of the rupture appears more localized and thus possibly structurally simpler. Eventually, the difference of slip between the western and eastern parts of the rupture is attributed to this difference of rupture localization, associated at first order with a lateral change in the local geology. Damage associated to rupture branching appears to be located asymmetrically along the extensional side of the strike‐slip rupture and shows a strong dependence on structural geologic inheritance.
Migration Imaging of the Java Subduction Zones
Authors: Dokht Ramin M. H. , Gu Yu Jeffrey , Sacchi Mauricio D.
Published: January 2018

Imaging of tectonically complex regions can greatly benefit from dense network data and resolution enhancement techniques. Conventional methods in the analysis of SS precursors stack the waveforms to obtain an average discontinuity depth, but smearing due to large Fresnel zones can degrade the fine‐scale topography on the discontinuity. To provide a partial solution, we introduce a depth migration algorithm based on the common scattering point method while considering nonspecular diffractions from mantle transition zone discontinuities. Our analysis indicates that, beneath the Sunda arc, the depth of the 410 km discontinuity (the 410) is elevated by 30 km and the 660 km discontinuity (the 660) is depressed by 20–40 km; the region of the strongest anticorrelation is correlated with the morphology of the subducting Indo‐Australian slab. In eastern Java, a “flat” 410 coincides with a documented slab gap, showing length scales greater than 400 km laterally and 200 km vertically. This observation could be explained by the arrival of a buoyant oceanic plateau at the Java trench at approximately 8 Ma ago, which may have caused a temporary cessation of subduction and formed a tear in the subducting slab. Our results highlight contrasting depths of the 410 and 660 along the shallow‐dipping slab below the Banda trench. The 660, however, becomes significantly uplifted beneath the Banda Sea, which is accompanied by enhanced reflection amplitudes. We interpret these observations as evidence for a subslab low‐velocity zone, possibly related to the lower mantle upwelling beneath the subducting slab.
Remote Triggering in the Koyna‐Warna Reservoir‐Induced Seismic Zone, Western India
Authors: Bansal Abhey Ram , Rao N. Purnachandra , Peng Zhigang , Shashidhar D. , Meng Xiaofeng
Published: January 2018

Dynamic triggering following large distant earthquakes has been observed in many regions globally. In this study, we present evidence for remote dynamic triggering in the Koyna‐Warna region of Western India, which is known to be a premier site of reservoir‐induced seismicity. Using data from a closely spaced broadband network of 11 stations operated in the region since 2005, we conduct a systematic search for dynamic triggering following 20 large distant earthquakes with dynamic stresses of at least 1 kPa in the region. We find that the only positive cases of dynamic triggering occurred during 11 April 2012, Mw8.6 Indian Ocean earthquake and its largest aftershock of Mw8.2. In the first case, microearthquakes started to occur in the first few cycles of the Love waves, and the largest event of magnitude 3.3 occurred during the first few cycles of the Rayleigh waves. The increase of microseismicity lasted for up to five days, including a magnitude 4.8 event occurred approximately three days later. Our results suggest that the Koyna‐Warna region is stress sensitive and susceptible for remote dynamic triggering, although the apparent triggering threshold appears to be slightly higher than other regions.
Attribution and Statistical Parameterization of the Sensitivity of Surface Ozone to Changes in Leaf Area Index Based On a Chemical Transport Model
Authors: Wong Anthony Y. H. , Tai Amos P. K. , Ip Yin‐Ying
Published: January 2018

Many studies have shown that global land cover change can significantly affect surface ozone air quality, albeit still with great uncertainties due to the complex pathways involved. In this study, we develop a framework to systematically examine the effects of any changes in foliage density as represented by leaf area index (LAI) on surface ozone concentration. We perform a series of perturbation experiments using the GEOS‐Chem chemical transport model. The spatial variability of the simulated results is used as a proxy to build a statistical model to quantify the sensitivity of surface ozone to LAI changes, which is found to arise mostly from the associated changes in dry deposition velocity and isoprene emission rate, whereas other factors and second‐order effects are negligible. The spatial variations of ozone responses to LAI changes are found to be the most correlated with anthropogenic NOx emission, biogenic isoprene emission, wind speed, ozone concentration, baseline LAI, and changes in LAI. We also show that the sign of change in surface ozone under future LAI changes for a given location can be inferred by distinguishing between three different regimes based on local anthropogenic NOx emission and LAI. The statistical model is optimized so that it is applicable to a wide range of LAI changes and can be used as a quick assessment tool to estimate the impacts of various land use policies on ozone air quality, and a diagnostic tool to estimate the relative contribution of different pathways toward the overall ozone‐LAI relationship.
First Effort for Constructing a Direct Solar Radiation Data Set in China for Solar Energy Applications
Authors: Tang Wenjun , Yang Kun , Qin Jun , Min Min , Niu Xiaolei
Published: January 2018

Accurate estimate of direct solar radiation is a prerequisite for the design of concentrated solar power thermal systems; however, direct radiation observations are very sparse compared to observations of routine meteorological variables. Therefore, this study developed a method for estimating daily direct radiation from routine observations, based mainly on a clear‐sky physical model to compute clear‐sky direct radiation and a parameterized formula to compute cloud transmittance from sunshine duration data. The parameters of the cloud transmittance formula were calibrated with high‐quality radiation data measured in the United States. The validation results at independent stations in the United States were comparable to those at the calibration stations, indicating that the method is suitable for various climatic and geographic conditions. We applied this method to compile a long‐term, high‐density data set of daily direct radiation over China based on observations from 2,473 routine weather stations of the China Meteorological Administration (CMA) network. Although the root‐mean‐square error of the data set from the 20 CMA radiation stations at which the direct solar radiations have been observed since 1993 is about 27.3 W m−2, the accuracy of the data set for CMA routine weather stations with less severe air pollution should be better. The newly developed data set in this study, which is available upon request, will contribute to the development of concentrated solar power thermal systems throughout China.
Adaptive sliding mode control for fuzzy singular systems with time delay and input nonlinearity
Authors: Kchaou Mourad , Gassara Hamdi , El‐Hajjaji Ahmed
Published: January 2018

This paper addresses the sliding mode control problem for a class of uncertain Takagi‐Sugeno fuzzy singular systems with state delay and subject to input nonlinearity. Our purpose is focused on designing an adaptive sliding mode controller for such a complex system. First, a new fuzzy integral‐type sliding function is designed. Then, an adaptive sliding mode control scheme is established such that the resulting closed‐loop system is insensitive to all admissible uncertainties and satisfies the reaching condition. Moreover, delay‐dependent sufficient conditions are derived such that the admissibility and the L2‐L∞ performance requirement of the sliding mode dynamics can be guaranteed in the presence of time delays, external disturbances, and sector nonlinearity input. Finally, the validity and applicability of the proposed theory are illustrated by a numerical example.
Hybrid Silver Nanowire and Graphene‐Based Solution‐Processed Transparent Electrode for Organic Optoelectronics
Authors: Ricciardulli Antonio Gaetano , Yang Sheng , Wetzelaer Gert‐Jan A. H. , Feng Xinliang , Blom Paul W. M.
Published: January 2018

The research on transparent conductive electrodes is in rapid ascent in order to respond to the requests of novel optoelectronic devices. The synergic coupling of silver nanowires (AgNWs) and high‐quality solution‐processable exfoliated graphene (EG) enables an efficient transparent conductor with low‐surface roughness of 4.6 nm, low sheet resistance of 13.7 Ω sq−1 at high transmittance, and superior mechanical and chemical stabilities. The developed AgNWs–EG films are versatile for a wide variety of optoelectronics. As an example, when used as a bottom electrode in organic solar cell and polymer light‐emitting diode, the devices exhibit a power conversion efficiency of 6.6% and an external quantum efficiency of 4.4%, respectively, comparable to their commercial indium tin oxide counterparts.
Strong Enhancement of PbS Quantum Dot NIR Emission Using Plasmonic Semiconductor Nanocrystals in Nanoporous Silicate Matrix
Authors: Litvin Aleksandr P. , Babaev Anton A. , Dubavik Aliaksei , Cherevkov Sergei A. , Parfenov Peter S. , Ushakova Elena V. , Baranov Mikhail A. , Andreeva Olga V. , Purcell‐Milton Finn , Gun'ko Yurii , Fedorov Anatoly V. , Baranov Alexander V.
Published: January 2018

Strong enhancement of near‐infrared (NIR) emission of lead sulfide quantum dots (QDs) induced by Cu2−xSe semiconductor plasmonic nanocrystals (PNCs), both embedded into nanoporous silicate matrix is reported. The emission enhancement comes from resonant interaction of QD optical transition dipole with the near field of plasmons of semiconductor PNCs. Possible mechanisms of QD photoluminescence broadening and shift, including Rabi splitting and trap‐state‐related photoluminescence enhancement, are considered. As a result, a novel optical luminescent material, which can be used as an efficient source of NIR emission is demonstrated.
Triflic acid‐Mediated Expedient Synthesis of Benzo[a]fluorenes and Fluorescent Benzo[a]fluorenones
Authors: Mandal Mou , Balamurugan Rengarajan
Published: January 2018

Fluorene‐based polyaromatic hydrocarbons are renowned compounds for materials applications. Herein, a straightforward route via in situ acetal formation has been presented to access benzo[a]fluorenes by a triflic acid promoted cationic cycloisomerization of enynones in presence of trimethyl orthoformate under metal‐free conditions. In the absence of trimethyl orthoformate, the same reaction results in benzo[a]fluorenones. All the synthesized benzo[a]fluorenones are highly fluorescent in solution phase with high Stokes shift while the corresponding benzo[a]fluorenes are not fluorescent.

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Harmonizing Energy and Power Density toward 2.7 V Asymmetric Aqueous Supercapacitor
Authors: Xiong Ting , Tan Teck Leong , Lu Li , Lee Wee Siang Vincent , Xue Junmin
Published: January 2018

Tremendous research efforts are devoted to developing wide potential window aqueous supercapacitors to resolve their low energy density concern. While the operational potential window is dictated by the intrinsic electrochemical stability of water (1.23 V), such a bottleneck may be surpassed by leveraging the additional overpotential of the oxygen evolution reaction and the hydrogen evolution reaction (HER). Herein, by employing an electroreduction technique, Na+ is adsorbed onto the carbon negative electrode which effectively acts as a physical barrier to hinder intermediate HER product formation, thereby reducing HER activity. To complement the wide potential carbon electrode, Na0.25MnO2 is employed as the positive electrode to take advantage of the extra energy (i.e., increased overpotential) required for Na+ insertion process into the structure. The asymmetric supercapacitor exhibits high energy density of 61.1 W h kg−1 at a power density of 982 W kg−1, and even at an ultrahigh power density of 42.9 kW kg−1, a respectable energy density of 16.3 W h kg−1 is attained. In addition, 93.7% capacitance retention is recorded after cycling for 10 000 cycles which further demonstrates its suitability as supercapacitor. The present success in fabricating a 2.7 V asymmetric supercapacitor will open a promising research route toward achieving high energy density and high power density.
Wireless Electric Energy Transmission through Various Isolated Solid Media Based on Triboelectric Nanogenerator
Authors: Liu Guanlin , Chen Jie , Tang Qian , Feng Li , Yang Hongmei , Li Jien , Xi Yi , Wang Xue , Hu Chenguo
Published: January 2018

Wireless electric energy transmission is an important energy supply technology. However, most wireless energy supply based on electromagnetic induction cannot be used for energy transmission through a metal chamber. Herein, a novel idea for wireless electric energy transmission through various isolated solid media based on triboelectric nanogenerator (TENG) is presented. The electric energy is first transformed into mechanical vibration energy in mechanical wave that can propagate well in solid medium, and then the vibration energy is harvested by a TENG. By employing the spring steel sheets and freestanding triboelectric‐layer structure, the vibration TENG as an energy conversion unit has the advantages of high efficiency and facilitation, boosting this wireless energy transmission technology to be an alternative way of delivering electric energy through metal medium. The working principle and output performance have been systematically studied. A commercial capacitor can be charged from 0 to 10 V in 33 and 86 s isolated by an acrylic plate and a copper plate in thickness of 3 mm, respectively. The wireless electric transmission technology is also applied to deliver electric energy into a vacuum glove box and across glass wall successfully. This novel technology has great potential applications in implantable microelectronic devices, encrypted wireless communication, and even nondestructive testing.
Lewis Acid‐Catalyzed Yne‐Carbonyl Metathesis of Ynamides and Cyclobutanones: Facile Synthesis of Functionalized Alkylidenecyclobutanes
Authors: Sun Yu‐Li , Chen Ling , Cao Jian , Sun Feng‐Na , Xu Zheng , Zheng Zhan‐Jiang , Cui Yu‐Ming , Xu Li‐Wen
Published: January 2018

An atom‐economical strategy for the synthesis of functionalized alkylidenecyclobutanes (ACBs) via Lewis acid‐catalyzed yne‐carbonyl metathesis of ynamides and cyclobutanones is described. This strategy features mild reaction conditions, ready availability of starting materials, and broad functional group tolerability. Furthermore, the imide group is easily converted to acid, ester, and amide, thus providing an efficient access to various functionalized ACBs.
RNA Cloaking by Reversible Acylation
Authors: Kadina Anastasia , Kietrys Anna M. , Kool Eric T.
Published: January 2018

We describe a selective and mild chemical approach for controlling RNA hybridization, folding, and enzyme interactions. Reaction of RNAs in aqueous buffer with an azide‐substituted acylating agent (100–200 mm) yields several 2′‐OH acylations per RNA strand in as little as 10 min. This poly‐acylated (“cloaked”) RNA is strongly blocked from hybridization with complementary nucleic acids, from cleavage by RNA‐processing enzymes, and from folding into active aptamer structures. Importantly, treatment with a water‐soluble phosphine triggers a Staudinger reduction of the azide groups, resulting in spontaneous loss of acyl groups (“uncloaking”). This fully restores RNA folding and biochemical activity.
Silica‐Supported Pentamethylcyclopentadienyl Ytterbium(II) and Samarium(II) Sites: Ultrahigh Molecular Weight Polyethylene without Co‐Catalyst
Authors: Allouche Florian , Chan Ka Wing , Fedorov Alexey , Andersen Richard A. , Copéret Christophe
Published: January 2018

Designing highly active supported ethylene polymerization catalysts that do not require a co‐catalyst to generate electrophilic metal alkyl species is still a challenge despite its industrial relevance. Described herein is the synthesis and characterization of well‐defined silica‐supported cyclopentadienyl LnII sites (Ln=Yb and Sm) of general formula [(≡SiO)LnCp*]. These well‐defined surface species are highly activite towards ethylene polymerization in the absence of added co‐catalyst. Initiation is proposed to occur by single electron transfer.
Inhibition of the CSF‐1 receptor sensitizes ovarian cancer cells to cisplatin
Authors: Yu Rong , Jin Hao , Jin Congcong , Huang Xuefeng , Lin Jinju , Teng Yili
Published: January 2018

Ovarian cancer is one of the most common female malignancies, and cisplatin‐based chemotherapy is routinely used in locally advanced ovarian cancer patients. Acquired or de novo cisplatin resistance remains the barrier to patient survival, and the mechanisms of cisplatin resistance are still not well understood. In the current study, we found that colony‐stimulating‐factor‐1 receptor (CSF‐1R) was upregulated in cisplatin‐resistant SK‐OV‐3 and CaoV‐3 cells. Colony‐stimulating‐factor‐1 receptor knockdown suppressed proliferation and enhanced apoptosis in cisplatin‐resistant SK‐OV‐3 and CaoV‐3 cells. However, CSF‐1R overexpression had inverse effects. While parental SK‐OV‐3 and CaoV‐3 cells were more resistant to cisplatin after CSF‐1R overexpression, CSF‐1R knockdown in SK‐OV‐3 and CaoV‐3 cells promoted cisplatin sensitivity. Overexpression and knockdown studies also showed that CSF‐1R significantly promoted active AKT and ERK1/2 signalling pathways in cisplatin‐resistant cells. Furthermore, a combination of cisplatin and CSF‐1R inhibitor effectively inhibited tumour growth in xenografts. Taken together, our results provide the first evidence that CSF‐1R inhibition can sensitize cisplatin‐refractory ovarian cancer cells. This study may help to increase understanding of the molecular mechanisms underlying cisplatin resistance in tumours.
Virginal breast hypertrophy in a patient with Beckwith–Wiedemann syndrome
Authors: Szymańska Edyta , Moszczyńska Elżbieta , Polnik Dariusz , Szymańska Sylwia , Jurkiewicz Elżbieta , Pyzlak Michał , Armata Michał , Walewska‐Wolf Małgorzata , Kaliciński Piotr , Rokicki Dariusz , Szalecki Mieczysław
Published: January 2018

Key Clinical Message

Virginal breast hypertrophy is a multidisciplinary condition including surgical, pediatric, and endocrine/gynecological disciplines, and its successful diagnosis and management requires complex, team approach.
Fracture of a femoral hemodialysis catheter during placement in a man with metastatic cancer
Authors: Li Xiang‐Yang , He Hai‐Yan , Pai Pearl
Published: January 2018

Key Clinical Message

Central venous catheterization can be challenging in patients that had undergone repeated catheter placements. Ultrasound scan may overlook venous stenosis which is better visualized using venography. The use of venography should be considered to assess for venous stenosis or vascular anomalies in individuals with multiple catheterizations or in close proximity to cancer.
Fatal cardiac arrhythmia caused by tumor lysis in a patient with diffuse large B‐cell lymphoma upon start of R‐CHOP
Authors: Sørensen Nina , Jensen Paw , Clasen‐Linde Erik , Larsen Jacob Moesgaard , El‐Galaly Tarec
Published: January 2018

Key Clinical Message

Tumor lysis syndrome is rare in diffuse large cell lymphoma, but it is important to recognize the risk in patients with massive tumor burden and reduced kidney function. Very intense vigilance can be necessary despite adequate prophylactic measures and certain drugs may exacerbate electrolyte derangements.
Ethyl Lactate Synthesis by Catalytic Membranes in a Pervaporation‐Assisted Membrane Reactor
Authors: Nigiz Filiz Ugur , Hilmioglu Nilufer Durmaz
Published: January 2018

A poly(styrenesulfonic acid)‐carboxymethylcellulose (PSSA‐CMC) blend catalytic membrane was prepared for ethyl lactate production in a pervaporation‐aided membrane reactor. The effects of PSSA/CMC concentration, initial molar ratio, and temperature on acid conversion were evaluated. Additionally, the separation performance of membrane was investigated as a function of flux and separation factor. Increasing the temperature enhanced lactic acid conversion at constant alcohol:acid ratio.
Stable Organic (Bi)Radicals by Delocalization of Spin Density into the Electron‐Poor Chromophore Core of Isoindigo
Authors: Rausch Rodger , Schmidt David , Bialas David , Krummenacher Ivo , Braunschweig Holger , Würthner Frank
Published: January 2018

The first isoindigo (bi)radicals were obtained by proton coupled oxidation of their 4‐hydroxyaryl substituted precursors. Optical and magnetic spectroscopic studies revealed a singlet open‐shell biradicaloid electronic ground state for the bisphenoxyl‐isoindigo (=1.20) with a small singlet–triplet energy gap of 0.065 eV and a large biradical character of y=0.79 that was corroborated by temperature‐dependent EPR spectroscopy and quantum chemical calculations. The concept of kinetic blocking of the radical centers and delocalization of spin density into the electron‐withdrawing chromophore core of isoindigo offers an entry into a new class of exceptionally stable open‐shell functional materials based on organic colorants.
C−C Bond Formation of Mg‐ and Zn‐Activated Carbon Dioxide
Authors: Miller Glenn B. S. , Uggerud Einar
Published: January 2018

Gas‐phase activation of CO2 by chloride tagged metal atoms, [ClM]− (M=Mg, Zn), has been investigated by mass spectrometry and high‐level quantum chemistry. Both metals activate CO2 with significant bending of the CO2 moiety to form complexes with the general formula [ClM,CO2]−. The structure of the metal–CO2 complex depends on the method of formation, and the energy landscapes and reaction dynamics have been probed by collisional induced dissociation and thermal ion molecule reactions with isotopically labeled species. Having established these structural relationships, the gas‐phase reactivity of [ClM(κ2‐O2C)]− with acetaldehyde (here considered a carbohydrate mimic) was then studied. Formation of lactate and enolate‐pyruvate complexes are observed, showing that CO2 fixation by C−C bond formation takes place. For M=Zn, even formation of free pyruvate ([C3H3O3]−) is observed. Implications of the observed CO2 reactivity for the electrochemical conversion of carbon dioxide, and to biochemical and artificial photosynthesis is briefly discussed. Detailed potential energy diagrams obtained by the quantum chemical calculations offer models consistent with experimental observation.
Asymmetric Catalytic Double Michael Additions for the Synthesis of Spirooxindoles
Authors: Kang Tengfei , Zhao Peng , Yang Jian , Lin Lili , Feng Xiaoming , Liu Xiaohua
Published: January 2018

Asymmetric cascade double Michael additions to construct 2′‐substituted 3,3′‐spirooxindoles by using a chiral guanidine organocatalyst has been developed. A series of spirooxindole derivatives containing dihydrofuran or pyrrolidine subunits were obtained with good to excellent diastereo‐ and enantioselectivities. The method showed great tolerance of a number of aromatic and aliphatic alkynones. The strategy gave access to the asymmetric synthesis of (−)‐salacin for the first time.
Intermolecular Desymmetrizing Gold‐Catalyzed Yne–Yne Reaction of Push–Pull Diarylalkynes
Authors: Weingand Vanessa , Wurm Thomas , Vethacke Vanessa , Dietl Martin C. , Ehjeij Daniel , Rudolph Matthias , Rominger Frank , Xie Jin , Hashmi A. Stephen K.
Published: January 2018

Push–pull diaryl alkynes are dimerized in the presence of a cationic gold catalyst. The polarized structure of the applied starting materials enables the generation of a highly reactive vinyl cation intermediate in an intermolecular reaction. Trapping of the vinyl cation by a nucleophilic attack of the electron‐poor aryl unit then leads to the selective formation of highly substituted naphthalenes in a single step and in complete atom economy.
Design of Metal Oxide Nanoparticles via Continuous Hydrothermal Synthesis
Authors: Türk Michael
Published: January 2018

Die außergewöhnlichen Eigenschaften von nahe‐ und überkritischem Wasser ermöglichen die Herstellung von metalloxidischen Nanopartikeln durch kontinuierliche hydrothermale Synthese. Dieser Prozess basiert auf dem Vermischen einer kalten, wässrigen Metallsalzlösung mit heißem Wasser unter Druck. Im Beitrag werden zunächst die für das Verständnis des Prozesses notwendigen Grundlagen und der aktuelle Stand des Wissens vorgestellt. Daran anschließend werden ausgewählte experimentelle und theoretische Ergebnisse präsentiert und diskutiert. Die wichtigsten Resultate werden zusammengefasst und ein Ausblick auf zukünftige Forschungsarbeiten wird gegeben.
The impact of illness‐related shame on psychological health and social relationships: Testing a mediational model in students with chronic illness
Authors: Trindade Inês A. , Duarte Joana , Ferreira Cláudia , Coutinho Mariana , Pinto‐Gouveia José
Published: January 2018

This study explores the impact of illness‐related shame on the quality of social relationships and psychological health in chronic patients. We aimed to examine the roles of fear of receiving compassion from others and experiential avoidance as potential mediators of this relationship. Although some studies have demonstrated the negative impact of chronic illness‐related shame on psychological functioning, the mechanisms that may underlie this link remain understudied.

The sample was comprised by 115 college students, which had been diagnosed with at least 1 chronic illness. Participants completed self‐report measures on an online platform. This study's design was cross‐sectional. A path analysis was conducted using structural equation modelling.

Results showed that the impact of illness‐related shame on both psychological health (R2 = .45) and the quality of social relationships (R2 = .33) was fully accounted by fear of compassion from others and experiential avoidance. This model revealed an excellent fit. Fear of receiving compassion from others was the main mediator of the illness‐related shame link with the quality of social relationships (β = −.22). The main mediator of the association between shame‐related chronic illness and psychological health was experiential avoidance (β = −.21).This study shed light on possible psychological mechanisms linking feelings of shame associated with having a chronic condition and impaired social relationships and mental health. On one hand, resisting feelings of compassion and care from others and, on the other hand, avoiding difficult internal experiences and situations that might trigger them seem to underlie the impact of shame on psychological and social functioning in chronic patients.
Reciprocal associations of pain and post‐traumatic stress symptoms after whiplash injury: A longitudinal, cross‐lagged study
Authors: Ravn S.L. , Sterling M. , Lahav Y. , Andersen T.E.
Published: January 2018

Background

The objectives of the current study were to investigate (1) the longitudinal, reciprocal associations between pain and post‐traumatic stress symptoms as proposed by the mutual maintenance model, and (2)  to assess the predictive value of the three clusters of post‐traumatic stress, where the model revealed that post‐traumatic stress symptoms maintained pain in a consecutive cohort of whiplash‐injured.

Methods

Participants (n = 253; 66.4% women) were people with WAD grades I–III following motor vehicle crashes in Australia. Pain and post‐traumatic stress symptoms were assessed by questionnaires over the course of a year (at baseline (<4 weeks), 3, 6 and 12 months post‐injury). The objectives were tested using auto‐regressive cross‐lagged modelling and two additional structural equation models.

Results

The analyses revealed that post‐traumatic stress symptoms at baseline predicted an increase in pain between baseline and 3 months and that post‐traumatic stress symptoms at 6 months predicted an increase in pain between 6 and 12 months, beyond the stability of pain over time. Furthermore, hyperarousal at baseline significantly predicted pain at 3 months and hyperarousal at 6 months significantly predicted pain at 12 months with 16 and 23% explained variance, respectively. [Correction added on 2 March 2018 after first online publication: the explained variance for hyperarousal symptoms at 6 months was previously given incorrectly and has been corrected to 23% in this version.]

Conclusions

The results point to a temporal main effect of post‐traumatic stress symptoms on pain over and above the stability of pain itself within the first 3 months post‐injury and again in the chronic phase from 6 to 12 months with hyperarousal symptoms driving these effects. From 3 to 6 months, there was a slip in the maintenance patterns with no cross‐lagged effects.

Significance

Investigating mutual maintenance of pain and PTSS in whiplash, the present study found evidence suggesting a maintaining effect of PTSS on pain within the first 3 months post‐injury and from 6 to 12 months driven by hyperarousal, highlighting the importance of addressing PTSS.
A Sensitive Electrochemical Sensor for Voltammetric Determination of Ganciclovir Based on Au‐ZnS Nanocomposite
Authors: Yari Abdollah , Shams Azim
Published: January 2018

An electrode modified with ZnS and gold nanoparticles (Au‐ZnS NPs) is introduced for highly sensitive voltammetric determination of ganciclovir (GCV). Surface structure and topography of the modified electrode was studied by SEM, EDX and XRD techniques. Electrochemical oxidation of GCV was investigated by cyclic (CV) and square wave voltammetry (SWV) in Briton‐Robinson buffer solution (pH 1.5). The results showed that electrochemical oxidation of GCV at the Au‐ZnS modified glassy carbon electrode (GCE) is irreversible and exhibited diffusion controlled electrode process over the pH range from 1.0 to 6.0. The oxidation potential peak and pH relationship showed that electrons and protons were transferred simultaneously over the electrochemical oxidation process. Using the proposed sensor, the linear calibration curves were obtained in the ranges of 0.04–1.50 μM and 1.5–70.0 μM with detection limit of 0.01 μM GCV by SWV technique. The modified electrode was successfully applied as a sensitive, reproducible and repeatable sensor for determination of the trace amount of GCV in human serum, urine and cymevene vials. Reasonable results were obtained from comparing the measurements of the real samples by the new sensor to high performance liquid chromatography (HPLC) as a standard method.
Syngas Production from Chemical‐Looping Reforming of Methane Using Iron‐Doped Cerium Oxides
Authors: Yan Yuyuan , Xu Long , Wang Li , Fu Ke , Tang Mingchen , Fan Maohong , Ma Xiaoxun
Published: January 2018

A series of iron‐doped cerium oxide oxygen carriers CexFe10−xOδ (x=9, 7, 5) were prepared by citric acid sol‐gel method and characterized by X‐ray powder diffraction (XRD), Brunauer Emmett Teller (BET), Temperature‐Programmed Reduction, and Oxidation (H2‐TPR/O2‐TPO). The reaction activity and cycle stability of oxygen carriers with methane at 850 °C were investigated in a fixed bed reactor and the capacity of oxygen storage was studied by a chemical adsorption instrument. Results showed that methane conversion and oxygen storage capacity of oxygen carriers were improved significantly because of the doping iron oxide. For thermostatic cycle, Ce7Fe3Oδ showed considerable durability. A three stages isothermal reaction mechanism was proposed.