bluuebunny/crossref_metadata_2025 huggingface dataset:
Tendência, variação espacial da soja e caracterização socioeconômica de municípios produtores do Paraná, Brasil
Authors: Carmello Vinicius
Published: July 2018

The Paraná State in Southern Brazil is the second most soybean producer from Brazil; Paraná comes behind only the Mato Grosso state in Brazilian central area. This paper aims to analyze the soybean trend and spatial variation productivity data, as well as carry out a social and economic characterization of the municipalities producers and thus create regional indicators unfold different patterns of productivity of soybean in a representative region of Paraná in the years between 1999 to 2010. To finish this research was collected soybean data from 132 counties. These counties represent the southern slope of Paranapanema river basin. Was applied two statistic testes: Mann-Kendall and the Ward. The results were represented in cartographic system and boxplots graphics and they showed the visible soybean yield crop and spatial variation between all counties. The crop and spatial variation have relation with agriculture characteristics analyzed by IBGE data.
Thermo-hygrometric modeling using ENVI-met® software to an urban park in Cuiabá – Brazil
Authors: Joaquim Thiago D'Orazio , Novais Jonathan Willian Zangeski , Andrade Levi Pires de , Rosseti Karyna De Andrade Carvalho , Vilani Maricéia Tatiana , Pereira Susana Pacheco
Published: July 2018

Climate in urban areas, not under the effect of vegetation, was investigated and its benefits were observed in both vegetated and un-vegetated areas. The objective of this research was to model the air temperature and relative humidity using the Software ENVI-met® in an urban park in Cuiabá. The development of the methodology of this work involved two phases: survey (microclimate) and simulation. The microclimate survey was conducted through a mobile transect, for the periods of January 2014 to March 2014 (hot/wet) and July 2015 to September 2015 (hot/dry). The simulation was developed using ENVI-met® software during these two periods of the year. Generally maximizing the parameters, the ENVI-met® model for microclimate varied in the presence of too much vegetation. Simulations showed an increase in temperature and relative humidity in areas not surrounding the Mãe Bonifacia City Park, and this was particularly apparent in areas laid with asphalt and concrete. Vegetated parks play an important role in how hot climate thermoregulatory agents behave in the city of Cuiabá and the surrounding region.
Artisanal fishing characterization and spatio-temporal occurrence of marine shrimp (Crustacea, Decapoda, Penaeidae) in the littoral of Lucena, Paraíba, Brazil
Authors: Nascimento Glória Cristina Cornélio do , Costa Dimitri De Araújo , Sá Raquel Ferreira de , Christoffersen Martin Lindsey , Crispim Maria Cristina Basilio
Published: July 2018

The present study distinguishes types of fishing activities. It records the most economically exploited shrimps in the municipality of Lucena, Paraíba, Xiphopenaeus kroyeri (“espigudo”), and Penaeus schmitti (white shrimp). From October 2014 to October 2015, samples containing 700 gr of shrimp were collected at three sites of artisanal fishing. Data on temperature, ammonium, nitrate, nitrite, chlorophyll-a, salinity, pH, and dissolved oxygen were recorded.  Two different shrimp species are commercially used in the region, of 2,628 sampled individuals, X. kroyeri predominated, with 1,957 individuals, followed by P. schmitti, with 671 individuals. At localities 1 (in Lucena beach) and 2 (Fagundes beach) both species were present, the X. kroyeri being predominant, but at locality 3 (Costinha beach) only the P. schmitti was recorded. The regional wet season influenced salinity during the months of the year, producing positive or negative correlations among species found at each locality depending on what was analysed. It is relevant to understand the relationship between fishing resources and environmental variables which provide information about fishing dynamics and permits the development of strategies for the maintenance of stocks and fishing areas, as well as permitting the establishment of public regulations for the better preservation and conservation of marine areas and estuaries on which many species depend for the completion of their life cycles.
A destruição da natureza em ambientes rurais e urbanos no Brasil – uma tragédia que ainda pode ser revista
Authors: Castilho Cláudio Jorge Moura de , Pontes Bruno Bruno Augusto Nogueira Monteiro , Brandão Robson José Alves
Published: July 2018

This article aims to denounce the permanent process of the nature’s destruction as a tragedy in the time-space, which is based on research carried out in rural and urban environments located in the Brazilian Northeast, in the current context of the acceleration in terms of generating values as a major goal of capitalism. The methodology of this work was based on a relational approach with regard to the process of geographical space’s production, considering, mainly, the dialectical interrelationship between its material and immaterial dimensions, shaping a complex totality in permanent movement in the history of men and women. The elaboration of maps and representative figures of the object being treated were technical procedures used to reinforce the argument, which had as main result the defense of the idea that it is still possible to change the current process of nature’s destruction, through the analysis of the cases occurred in two microregions located in the West of Bahia and in a coastal area of the Metropolitan Region of Recife.
Estudo cooperativo: uma interessante prática para o sucesso acadêmico
Authors: Bezerra João Inácio Moreira , Pergher Rejane
Published: July 2018

High failure rates in the Differential and Integral Calculus courses and the subsequent dropout caused by them are a reason for concern in many universities around the world, both in developing countries such as Brazil and developed ones such as the United States of America. So, it is not surprising that there is lots of interest in researching about this context, and possible ways of action. This is the focus of this article, to study about the origins of this situation, analyzing the causes of the students’ difficulties and presenting Collaborative Learning as an effective way to change this situation. The article is based on data from several universities that have shown interest in this method. The results demonstrate the effectiveness of this practice, both in academic and psychological performance of the students, thus showing the need for a greater incentive of this technique, as well as an intense study of the way it should be done.
Synoptic patterns for days with intense atmospheric electrical activity from 2013 to 2015
Authors: Rodrigues Vanessa Gehm , Piva Everson Dal , Puhales Franciano Scremin , Anabor Vagner
Published: July 2018

The following study aimed to analyze data from Atmospheric Electric Discharge (AEDs) from the period between 2013 to 2015, with the objective of obtaining atmospheric patterns for the days with the maximum AED detected near the city of Santa Maria, in the state of Rio Grande do Sul. Data from the Sferics Timing and Ranging NETwork (STARNET) have been used. With a FORTRAN routine, a search at the AED data was performed to obtain the daily maximum of AED in an area of 1 ° per 1 ° centered in the city Santa Maria.One day of each year were found with maximum numbers of AEDs.The gridded atmospheric dataset used to dynamic and thermodynamic analysis were the final analysis from the National Centers for Environmental Prediction (NCEP).The main characteristics found were the proximity of the equatorial entrance of the high-level jet streak and the thermodynamics indices indicating moderate-to-high possibility for storm occurrence. This analysis enabled in the atmospheric characterization associated to events with large daily amount of DEAs and can be used to improve forecast.
Conocimiento histórico y evaluación de competencias en los exámenes de Educación Secundaria. Un análisis comparativo España-Inglaterra
Authors: Gómez Carrasco Cosme J. , Monteagudo Fernández José , Miralles Martínez Pedro
Published: July 2018

Este artículo analiza el conocimiento histórico
evaluado en los exámenes de Inglaterra
y España al finalizar la Educación
Secundaria Obligatoria. Para ello se ha recogido
una muestra de carácter incidental
con un total de 40 exámenes (20 por cada
país) y 400 preguntas. Para analizar estos
documentos se ha diseñado una base de
datos con diferentes categorías: tipología
de preguntas; nivel cognitivo exigido;
conceptos de pensamiento histórico evaluados.
Los datos cuantitativos han sido

exportados al programa estadístico SPSS
19.0 para analizar las frecuencias, porcentajes
y la relación entre variables. Los
resultados diferencias significativas entre
ambos países. Mientras que en España
sigue primando el conocimiento conceptual
y memorístico de hechos, datos y
conceptos, en Inglaterra se prima más los
aspectos metodológicos: uso de pruebas
históricas, análisis de fuentes, y argumentación
histórica.
El uso de la televisión en el hogar y en el aula de Educación Primaria
Authors: López-Mondéjar Loida M.
Published: July 2018

El presente artículo expone los resultados
obtenidos en una investigación llevada a
cabo en el alumnado de Educación Primaria
sobre el consumo que se realiza
del medio televisivo en el hogar, así como
sobre el uso que se hace del mismo en el
aula escolar. El estudio ha sido desarrollado
en diferentes centros educativos de la
Región de Murcia con alumnado (N = 320)
de entre 9 y 10 años de edad y está enmarcado
dentro de una investigación de carácter
descriptivo donde se ha utilizado la técnica
de encuesta. Los resultados muestran
que la televisión sigue siendo uno de los
medios más utilizados por el alumnado de
Educación Primaria en el hogar, señalada
como segunda actividad más deseada después
de ‘jugar con los amigos’. También sacan
a la luz la tendencia generalizada, por
parte del profesorado, de escaso uso de la
televisión en el aula para el desarrollo de
contenidos curriculares, así como la falta
de trabajo con los alumnos sobre los contenidos
visualizados. Siendo la televisión
uno de los medios de comunicación más
utilizados por los niños, este escaso uso
que se realiza de la misma desde el aula
escolar evidencia la gran separación entre
escuela y sociedad y, por tanto, el absurdo

que los niños viven en relación a los modelos
educativos y procesos de enseñanzaaprendizaje
desarrollados en la escuela y
sus actividades fuera de la misma.
¿Hemos cambiado? La perspectiva de los profesores eméritos sobre el cambio educativo en la universidad
Authors: Trillo Alonso Felipe , Zabalza Beraza Miguel , Zabalza Cerdeiriña María Ainoa
Published: July 2018

El presente trabajo forma parte de una in-
vestigación más amplia desarrollada en el
marco de una convocatoria nacional de
I+D 2  en la que han participado varias uni-
versidades españolas. Su objetivo princi-
pal fue recuperar el conocimiento experto
del profesorado emérito, esto es, recons-
truir el proceso personal y profesional se-
guido por profesores-as que han sido muy
relevantes en el mundo de la docencia y
de la investigación.
En este trabajo se presentan e interpre-
tan las reflexiones que sobre los procesos
de cambio, de reforma, de innovación y/o

de mejora educativa en la universidad, ex-
presan 20 profesores eméritos de 13 uni-
versidades públicas españolas. El acceso a
la visión personal de los profesores eméri-
tos se efectuó mediante la realización de
una entrevista semi-estructurada. Los da-
tos que resultan de sus respuestas han sido
sometidos a un análisis de contenido del
que se derivan muchas consideraciones,
valoraciones y recomendaciones dignas
de ser tomadas en consideración para  la
comprensión de las transformaciones
acaecidas en la universidad a lo largo del
amplio período que abarca su trayectoria
profesional (1965-2015).
Traduction de genres économiques de l’espagnol vers l’allemand, le français et l’anglais et vice-versa. Enquête auprès d’entreprises exportatrices
Authors: Gallego-Hernández Daniel , Tolosa-Igualada Miguel , Masseau Paola
Published: July 2018

Nous cherchons dans cet article à compléter une série de travaux sur la traduction de genres appartenant à l’économie et aux affaires : de l’espagnol vers l’allemand, le français et l’anglais et vice-versa. Nous avons conçu une enquête comme instrument pour collecter des données auprès des entreprises qui, par leurs caractéristiques, sont susceptibles d’avoir besoin des services d’un traducteur pour mener à bien leurs activités commerciales. L’objectif de cette enquête est d’identifier les genres et les domaines économiques le plus fréquemment traduits. Les résultats obtenus montrent des similitudes et des différences entre notre enquête et les travaux dont nous rendons compte et peuvent être pris en compte à différentes fins, notamment pour ce qui est de la formation de futurs traducteurs. À moyen terme, notre objectif principal étant d’aider les formateurs à concevoir leurs programmes.
Translators’ Perspectives: The Construction of the Peruvian Indigenous Languages Act in Indigenous Languages
Authors: De Pedro Ricoy Raquel , Howard Rosaleen , Andrade Ciudad Luis
Published: July 2018

An urgent need is emerging in contemporary Latin America for the translation of legal texts from the languages of former European colonial powers into the many indigenous languages spoken across the region. This article addresses the issue in relation to the rise of legislation that requires States to uphold the principle of linguistic human rights. It takes as a case study the translation of the Peruvian Indigenous Languages Act (2011) from Spanish into five Amerindian languages, viewed as a postcolonial practice situated at the communicative interface between the State and the country’s indigenous populations. Our specific interest is the strategic behavior of the indigenous translators, as described by themselves, when communicating to their peoples the State norms contained in the Indigenous Languages Act. In order to analyze this behavior, we depart from text-analytical models and favor an approach based on the translators’ perceptions of their role and their rationales for the translation solutions adopted. The analysis combines theoretical strands from translation studies, legal studies and postcolonial studies so as to throw light on the translation of legal discourse from Spanish into the indigenous languages of Peru, as conducted, crucially, by bilingual translators situated on the cultural “inside.”
Deux haïkus de Bashô (étude comparative de quelques traductions françaises)
Authors: Marukawa Seiji
Published: July 2018

L’article compare plusieurs traductions françaises de deux haïkus de Bashô (1644-1694). Il s’agit moins d’observer l’amélioration accomplie au travers des années que de voir encore en quoi peut consister la soi-disant intraduisibilité de la poésie d’une langue si éloignée des langues indo-européennes. Si l’harmonie d’une langue mise en valeur dans la poésie n’est pas traduisible comme l’a dit Dante, il faudrait, concernant le chinois ou le japonais, ajouter « l’harmonie imitative » (Claudel), que propose la picturalité des signes et qui joue un certain rôle dans la poésie écrite dans ces langues. Pour la traduction d’un poème aussi bref (et dont l’énoncé risque de paraître si plat dans la traduction), doit-on se contenter de rendre seulement le sens ? Et s’il n’y a pas d’autres moyens, comment entreprendre cette traduction ? L’article aborde ces questions à travers l’analyse des versions françaises de deux haïkus. Or, même pour la restitution du sens, il y a des problèmes : le premier exemple soulève la question de l’ellipse agrammaticale de l’original, devant être complétée dans les traductions, et le deuxième, le rôle de la particule de ponctuation servant de césure, idiomatique et intraduisible. Il s’agit des rapports au non-dit ou aux sentiments inexprimables que la brièveté met encore en relief.
Japanese knotweed (Fallopia japonica): an analysis of capacity to cause structural damage (compared to other plants) and typical rhizome extension
Authors: Fennell Mark , Wade Max , Bacon Karen L.
Published: July 2018

Fallopia japonica(Japanese knotweed) is a well-known invasive alien species in the UK and elsewhere in Europe and North America. The plant is known to have a negative impact on local biodiversity, flood risk and ecosystem services; but in the UK it is also considered to pose a significant risk to the structural integrity of buildings that are within seven m of the above ground portions of the plant. This has led to the presence of the plant on residential properties regularly being used to refuse mortgage applications. Despite the significant socioeconomic impacts of such automatic mortgage option restriction, little research has been conducted to investigate this issue. The ‘seven-m rule’ is derived from widely adopted government guidance in the UK. This study considered if there is evidence to support this phenomenon in the literature, reports the findings of a survey of invasive species control contractors and property surveyors to determine if field observations support these assertions, and reports a case study of 68 properties, located on three streets in northern England whereF. japonicawas recorded. Additionally, given the importance of proximity, the seven-m rule is also tested based on data collected during the excavation based removal ofF. japonicafrom 81 sites. No support was found to suggest thatF. japonicacauses significant damage to built structures, even when it is growing in close proximity to them and certainly no more damage than other plant species that are not subject to such stringent lending policies. It was found that the seven-m rule is not a statistically robust tool for estimating likely rhizome extension.F. japonicarhizome rarely extends more than four m from above ground plants and is typically found within two m for small stands and 2.5 m for large stands. Based on these findings, the practice of automatically restricting mortgage options for home buyers whenF. japonicais present, is not commensurate with the risk.
Performance comparison of machine learning techniques in sleep scoring based on wavelet features and neighboring component analysis
Authors: Alizadeh Savareh Behrouz , Bashiri Azadeh , Behmanesh Ali , Meftahi Gholam Hossein , Hatef Boshra
Published: July 2018

Introduction

Sleep scoring is an important step in the treatment of sleep disorders. Manual annotation of sleep stages is time-consuming and experience-relevant and, therefore, needs to be done using machine learning techniques.

Methods

Sleep-EDF polysomnography was used in this study as a dataset. Support vector machines and artificial neural network performance were compared in sleep scoring using wavelet tree features and neighborhood component analysis.

Results

Neighboring component analysis as a combination of linear and non-linear feature selection method had a substantial role in feature dimension reduction. Artificial neural network and support vector machine achieved 90.30% and 89.93% accuracy, respectively.

Discussion and Conclusion

Similar to the state of the art performance, the introduced method in the present study achieved an acceptable performance in sleep scoring. Furthermore, its performance can be enhanced using a technique combined with other techniques in feature generation and dimension reduction. It is hoped that, in the future, intelligent techniques can be used in the process of diagnosing and treating sleep disorders.
Antinuclear Antibody–Negative Systemic Lupus Erythematosus in an International Inception Cohort
Authors: Choi May Y. , Clarke Ann E. , St. Pierre Yvan , Hanly John G. , Urowitz Murray B. , Romero‐Diaz Juanita , Gordon Caroline , Bae Sang‐Cheol , Bernatsky Sasha , Wallace Daniel J. , Merrill Joan T. , Isenberg David A. , Rahman Anisur , Ginzler Ellen M. , Petri Michelle , Bruce Ian N. , Dooley Mary A. , Fortin Paul R. , Gladman Dafna D. , Sanchez‐Guerrero Jorge , Steinsson Kristjan , Ramsey‐Goldman Rosalind , Khamashta Munther A. , Aranow Cynthia , Alarcón Graciela S. , Manzi Susan , Nived Ola , Zoma Asad A. , van Vollenhoven Ronald F. , Ramos‐Casals Manuel , Ruiz‐Irastorza Guillermo , Lim S. Sam , Kalunian Kenneth C. , Inanc Murat , Kamen Diane L. , Peschken Christine A. , Jacobsen Soren , Askanase Anca , Stoll Thomas , Buyon Jill , Mahler Michael , Fritzler Marvin J.
Published: July 2018

Objective

The spectrum of antinuclear antibodies (ANAs) is changing to include both nuclear staining as well as cytoplasmic and mitotic cell patterns (CMPs) and accordingly a change is occurring in terminology to anticellular antibodies. This study examined the prevalence of indirect immunofluorescence (IIF) anticellular antibody staining using the Systemic Lupus International Collaborating Clinics inception cohort.

Methods

Anticellular antibodies were detected by IIF on HEp‐2000 substrate using the baseline serum. Three serologic subsets were examined: ANA positive (presence of either nuclear or mixed nuclear/CMP staining), anticellular antibody negative (absence of any intracellular staining), and isolated CMP staining. The odds of being anticellular antibody negative versus ANA or isolated CMP positive was assessed by multivariable analysis.

Results

A total of 1,137 patients were included; 1,049 (92.3%) were ANA positive, 71 (6.2%) were anticellular antibody negative, and 17 (1.5%) had an isolated CMP. The isolated CMP–positive group did not differ from the ANA‐positive or anticellular antibody–negative groups in clinical, demographic, or serologic features. Patients who were older (odds ratio [OR] 1.02 [95% confidence interval (95% CI) 1.00, 1.04]), of white race/ethnicity (OR 3.53 [95% CI 1.77, 7.03]), or receiving high‐dose glucocorticoids at or prior to enrollment (OR 2.39 [95% CI 1.39, 4.12]) were more likely to be anticellular antibody negative. Patients on immunosuppressants (OR 0.35 [95% CI 0.19, 0.64]) or with anti‐SSA/Ro 60 (OR 0.41 [95% CI 0.23, 0.74]) or anti–U1 RNP (OR 0.43 [95% CI 0.20, 0.93]) were less likely to be anticellular antibody negative.

Conclusion

In newly diagnosed systemic lupus erythematosus, 6.2% of patients were anticellular antibody negative, and 1.5% had an isolated CMP. The prevalence of anticellular antibody–negative systemic lupus erythematosus will likely decrease as emerging nomenclature guidelines recommend that non‐nuclear patterns should also be reported as a positive ANA.
Chitosan‐Based Heparan Sulfate Mimetics Promote Epidermal Formation in a Human Organotypic Skin Model
Authors: Farrugia Brooke L. , Mi Yaolei , Kim Ha Na , Whitelock John M. , Baker Shenda M. , Wiesmann William P. , Li Zhe , Maitz Peter , Lord Megan S.
Published: July 2018

Biomimetic materials that replicate biological functions have great promise for use as therapeutics in regenerative medicine applications. Heparan sulfate (HS) is the natural binding partner for growth factors enabling longer half‐lives and potentiation of their signaling. In this study a water soluble chitosan‐arginine is modified with sulfate moieties in order to mimic the structure of HS. Sulfated chitosan‐arginine with a degree of sulfation of 58% binds fibroblast growth factor 2 with higher affinity than HS. The sulfated chitosan‐arginine also promotes epithelial cell migration and supports the formation of an expanded epidermis in an organotypic skin model. Furthermore, sulfated chitosan‐arginine promotes the expression of the HS proteoglycan, perlecan, by both epithelial and fibroblast cells. Perlecan itself modulates the activity of mitogens and is essential for the formation of the epidermis. The synthesized sulfated Ch‐Arg derivatives mimic HS, support formation of the epidermis, and thus have the potential to assist in wound healing.
High Efficiency Deep‐Blue Phosphorescent Organic Light‐Emitting Diodes with CIE x, y (≤ 0.15) and Low Efficiency Roll‐Off by Employing a High Triplet Energy Bipolar Host Material
Authors: Maheshwaran Athithan , Sree Vijaya Gopalan , Park Ho‐Yeol , Kim Hyein , Han Si Hyun , Lee Jun Yeob , Jin Sung‐Ho
Published: July 2018

Recently, bipolar host materials are the most promising candidates for achieving high performance phosphorescent organic light‐emitting diodes (PHOLEDs) in order to maximize recombination efficiency. However, the development of host material with high triplet energy (E
T) is still a great challenge to date to overcome the limitations associated with the present PHOLEDs. Herein, a highly efficient donor‐π‐acceptor (D‐π‐A) type bipolar host (4′‐(9H‐carbazol‐9‐yl)‐2,2′‐dimethyl‐[1,1′‐biphenyl]‐4‐yl)diphenylphosphine oxide (m‐CBPPO) comprising of carbazole, 2,2′‐dimethylbiphenyl and diphenylphosphoryl as D‐π‐A unit, respectively, is developed. Interestingly, a high E
T of 3.02 eV is observed for m‐CBPPO due to highly twisted conformation. Furthermore, the new host material is incorporated in PHOLEDs as emissive layer with a new carbene type Ir(cb)3 material as a deep‐blue emitter. The optimized devices show an excellent external quantum efficiency (EQE) of 24.8% with a notable Commission internationale de l'éclairage (x, y) ≤ 0.15, (0.136, 0.138) and high electroluminescence performance with extremely low efficiency roll‐off. Overall, the above EQE is the highest reported for deep‐blue PHOLEDs with very low efficiency roll‐off and also indicate the importance of appropriate host for the development of high performance deep‐blue PHOLEDs.
3D‐Plotted Beta‐Tricalcium Phosphate Scaffolds with Smaller Pore Sizes Improve In Vivo Bone Regeneration and Biomechanical Properties in a Critical‐Sized Calvarial Defect Rat Model
Authors: Diao Jingjing , OuYang Jun , Deng Ting , Liu Xiao , Feng Yanting , Zhao Naru , Mao Chuanbin , Wang Yingjun
Published: July 2018

Due to the difficulty in fabricating bioceramic scaffolds with smaller pore sizes by the current 3D printing technique, the effect of smaller pore sizes (below 400 µm) of 3D printed bioceramic scaffolds on the bone regeneration and biomechanical behavior is never studied. Herein beta‐tricalcium phosphate (β‐TCP) scaffolds with interconnected smaller pores of three different sizes (100, 250, and 400 µm) are fabricated by 3D plotting. The resultant scaffolds are then implanted into rat critical‐sized calvarial defects without any seeded cells. A custom‐designed device is developed to investigate the biomechanical properties of the scaffolds after surgical implantation for 4, 8, and 12 weeks. The scaffolds with the 100 µm pore size are found to present the highest maximum load and stiffness, comparable to those of the autogenous bone, after being implanted for 12 weeks. Micro‐computed tomography (micro‐CT) and histological analysis further indicate that the scaffolds with the 100 µm pore size achieve the highest percentage of new bone ingrowth, which correlates to their best in vivo biomechanical properties. This study demonstrates that tailoring the pore size of β‐TCP scaffolds to a smaller range by 3D‐plotting can be a facile and efficient approach to enhanced bone regeneration and biomechanical behaviors in bone repair.
Carbon‐Rich Nanomaterials: Fascinating Hydrogen and Oxygen Electrocatalysts
Authors: Zhang Jian , Chen Guangbo , Müllen Klaus , Feng Xinliang
Published: July 2018

Hydrogen energy is commonly considered as a clean and sustainable alternative to the traditional fossil fuels. Toward universal utilization of hydrogen energy, developing high‐efficiency, low‐cost, and sustainable energy conversion technologies, especially water‐splitting electrolyzers and fuel cells, is of paramount significance. In order to enhance the energy conversion efficiency of the water‐splitting electrolyzers and fuel cells, earth‐abundant and stable electrocatalysts are essential for accelerating the sluggish kinetics of hydrogen and oxygen reactions. In the past decade, carbon‐rich nanomaterials have emerged as a promising class of hydrogen and oxygen electrocatalysts. Here, the development and electrocatalytic activity of various carbon‐rich materials, including metal‐free carbon, conjugated porous polymers, graphdiyne, covalent organic frameworks (COFs), atomic‐metal‐doped carbon, as well as metal–organic frameworks (MOFs), are demonstrated. In particular, the correlations between their porous nanostructures/electronic structures of active centers and electrocatalytic performances are emphatically discussed. Therefore, this review article guides the rational design and synthesis of high‐performance, metal‐free, and noble‐metal‐free carbon‐rich electrocatalysts and eventually advances the rapid development of water‐splitting electrolyzers and fuel cells toward practical applications.
High‐Efficiency and Wide‐Angle Beam Steering Based on Catenary Optical Fields in Ultrathin Metalens
Authors: Guo Yinghui , Ma Xiaoliang , Pu Mingbo , Li Xiong , Zhao Zeyu , Luo Xiangang
Published: July 2018

Recent advances in artificial subwavelength structures promise the realization of ultrathin, lightweight, and flat metalens, providing a potential candidate for traditional bulky and curved lens. Nevertheless, most metalenses are generally suffering from serious off‐axis aberration, resulting in a limited field‐of‐view (FOV). Here, a methodology to extend the FOV of metalens is presented by exploring the local catenary optical fields and symmetry transformation from rotational symmetry to transversal symmetry. As a proof of the concept, a high efficiency (>80% even when the incidence angle is titled by 60°) and ultrathin (≈0.127 λ) metalens consisting of bilayer geometric metasurface is designed, fabricated, and characterized. The wide FOV of metalens benefiting from local catenary fields and symmetry transformation is numerically demonstrated by full‐wave simulation and ray tracing method. Moreover, the wide‐angle beam steering ability beyond ± 60° is experimentally demonstrated, which exhibits obvious advantages compared with previous beam steering transmitarrays. The novelty of the proposed methodology lies at the fact that both transversal and longitudinal local catenary fields are excited in a single component: the transversal catenary field is utilized for high efficiency spin–orbit interaction and phase modulation, while the longitudinal catenary field and symmetry transformation ensure wide‐angle operation.
Further evidence for complex inheritance of holoprosencephaly: Lessons learned from pre‐ and postnatal diagnostic testing in Germany
Authors: Hinreiner Sophie , Wieczorek Dagmar , Mueller Dietmar , Roedl Tanja , Thiel Gundula , Grasshoff Ute , Chaoui Rabih , Hehr Ute
Published: July 2018

Holoprosencephaly (HPE) has been defined as a distinct clinical entity with characteristic facial gestalt, which may—or may not—be associated with the true brain malformation observed postmortem in autopsy or in pre‐ or postnatal imaging. Affected families mainly show autosomal dominant inheritance with markedly reduced penetrance and extremely broad clinical variability even between mutation carriers within the same families. We here present advances in prenatal imaging over the last years, increasing the proportion of individuals with HPE identified prenatally including milder HPE forms and more frequently allowing to detect more severe forms already in early gestation. We report the results of diagnostic genetic testing of 344 unrelated patients for HPE at our lab in Germany since the year 2000, which currently with the application of next generation sequencing (NGS) panel sequencing identifies causal mutations for about 31% (12/38) of unrelated individuals with normal chromosomes when compared to about 15% (46/306) using conventional Sanger sequencing and Multiplex Ligation‐dependent Probe Amplification (MLPA). More comprehensive genetic testing by our in house NGS panel sequencing of 10 HPE associated genes (MiSeq™ and NextSeq™500, Illumina, Inc., San Diego, CA) not only allowed to include genes with smaller contribution to the phenotype, but may also unravel additional low frequency or more common genetic variants potentially contributing to the observed large intrafamiliar variability and may ultimately guide our understanding of the individual clinical manifestation of this complex developmental disorder.
Rh(III)‐Catalyzed C‐H Amination of Azobenzenes with Anthranils
Authors: Fu Ting , Yang Jun , Sun Huihui , Zhang Chichen , Xiang Haifeng , Zhou Xiangge
Published: July 2018

An efficient Rh(III)‐catalyzed C−H amination of azobenzenes with anthranils was developed. A range of azobenzenes were aminated under mild conditions in high yields (up to 92%) with good regioselectivity and atomic economy. The formed ortho‐aminocarbonyl skeleton could be converted to a series of biologically interesting heterocyclic compounds including a dibenzodiazepine, an acridine and an N‐aryl indole.
Concurrent Radical Addition and [3+2] Cycloaddition between Nitrones and Maleimide‐Based Acyclic Enediynes
Authors: Li Jing , Zhang Mengsi , Huang Shuai , Ding Yun , Hu Aiguo
Published: July 2018

Enediyne compounds undergo Bergman cyclization while being activated with thermal or UV‐light triggers, and generate benzyne diradical intermediates, endowing their great potential as antitumor agents. The radical nature of the Bergman cyclization is generally confirmed through radical trapping experiments. While using phenyl tert‐butyl nitrone (PBN) as a radical trapping agent to study the Bergman cyclization of maleimide‐based enediyne compounds, we uncovered concurrent radical addition and [3+2] cycloaddition reactions between nitrones and enediyne compounds. The radical addition between the diradical intermediates and PBN was revealed through EPR analysis, while the [3+2] cycloaddition products were separated out and their structures were confirmed by NMR, HRMS and single crystal XRD analysis. Computational investigations showed that the energy barrier of the [3+2] cycloaddition was much lower than that of the Bergman reaction, corroborating the dominance of [3+2] cycloaddition between nitrone and enediyne compounds.
Förster‐Resonanzenergietransfer‐basierter Nachweis intrazellulärer Ketal‐Hydrolyse in synthetisch vernetzten Nanopartikeln
Authors: Nuhn Lutz , Van Herck Simon , Best Andreas , Deswarte Kim , Kokkinopoulou Maria , Lieberwirth Ingo , Koynov Kaloian , Lambrecht Bart N. , De Geest Bruno G.
Published: July 2018

Der Einbau abbaubarer Vernetzungen gilt als vielversprechende Strategie, synthetische Nanopartikel, die durch Verdünnungs‐ und Verdrängungseffekte zerfallen könnten, in komplexen physiologischen Umgebung besser zu stabilisieren. Hierbei haben sich in vielen biomedizinischen Anwendungen Ketale als äußerst nützlich erwiesen, da sie unter physiologischen Bedingungen recht stabil sind, aber gegenüber krankheitsbedingt oder intrazellulär niedrigen pH‐Werten eine hohe Hydrolyseempfindlichkeit aufweisen. Trotz der Vielzahl an spektroskopisch oder chromatographisch zugänglichen Nachweismethoden, mit denen der chemische Abbau in Lösung recht einfach gezeigt werden kann, gestaltet sich der Nachweis einer Ketalhydrolyse innerhalb synthetischer Nanomaterialien durch lebende Organismen als schwierig. In dieser Arbeit stellen wir eine Förster‐Resonanzenergietransfer(FRET)‐basierte Methode vor, mit der die Disassemblierung Blockpolymer‐basierter Nanopartikel bestätigt wurde. Dabei wurden einzelne Ketten jeweils mit einem FRET‐Farbstoffpaar markiert, ehe sie nach Selbstassemblierung kovalent mit pH‐sensiblen Ketal‐Vernetzern stabilisiert wurden.
Dynamische Kopplung bei niedriger Reynoldszahl
Authors: Dey Krishna Kanti
Published: July 2018

Aktive Kolloide, bei denen kollektives und emergentes Verhalten auftritt, gewähren nützliche Einblicke in die statistische Physik von Nichtgleichgewichtssystemen. Um die Prinzipien des Energietransfers unter den Bedingungen einer niedrigen Reynoldszahl kennenzulernen, hat man Kolloidsuspensionen untersucht, die aktive Mikroschwimmer enthalten. Studien an aktiven Enzymen und metallorganischen Katalysatoren im Ångström‐Bereich belegten, dass bereits Moleküle Energie auf ihre Umgebung übertragen und dadurch die Gesamtdynamik des Systems substantiell beeinflussen können. Anhand der Diffusion von unreaktiven Tracern in einer aktiven Lösung wurde gezeigt, dass der Energietransfer in Systemen mit unterschiedlichen Schwimmern ähnlich abläuft – ungeachtet der Größe, der Art der Energieübertragung und des Antriebssystems des Schwimmers. Dieser Aufsatz diskutiert bisherige Forschungsergebnisse und die beobachteten Gemeinsamkeiten bei der dynamischen Kopplung von Schwimmern mit der Umgebung.
Intensely Photoluminescent Diamidophosphines of the Alkaline‐Earth Metals, Aluminum, and Zinc
Authors: Bestgen Sebastian , Schoo Christoph , Neumeier B. Lilli , Feuerstein Thomas J. , Zovko Christina , Köppe Ralf , Feldmann Claus , Roesky Peter W.
Published: July 2018

The positively charged and weakly polarizable s‐block metals commonly do not usually have phosphine ligands in molecular complexes. Herein, we report mono‐ and dinuclear small diamidophosphine complexes of the alkaline‐earth metals Mg, Ca, and Sr, which were prepared from simple precursors and a phosphine‐functionalized diamine ligand N,N‐bis(2‐(diphenyl‐phosphino)phenyl)ethane‐1,2‐diamine (PNHNHP). The alkaline‐earth metal based complexes [(PNNP)Mg]2 and [(PNNP)M(thf)3] (M=Ca, Sr), exhibit unusual coordination spheres and show bright fluorescence, both in the solid state and in solution. For comparison, the even stronger luminescent Al and Zn complexes [(PNNP)Zn]2 and [(PNNP)AlCl] were prepared. Emission lifetimes in the nanosecond range and high photoluminescence quantum yields up to 93 % are observed at room temperature.
Dissipative Self‐Assembly of Photoluminescent Silicon Nanocrystals
Authors: Grötsch Raphael K. , Angı Arzu , Mideksa Yonatan G. , Wanzke Caren , Tena‐Solsona Marta , Feige Matthias J. , Rieger Bernhard , Boekhoven Job
Published: July 2018

Solutions of silicon nanocrystals (SiNCs) are used in a diverse range of applications because of their tunable photoluminescence, biocompatibility, and the abundance of Si. In dissipative supramolecular materials, self‐assembly of molecules or nanoparticles is driven by a chemical reaction network that irreversible consumes fuel. The properties of the emerging structures are controlled by the kinetics of the underlying chemical reaction network. Herein, we demonstrate the dissipative self‐assembly of photoluminescent SiNCs driven by a chemical fuel. A chemical reaction induces self‐assembly of the water‐soluble SiNCs. However, the assemblies are transient, and when the chemical reaction network runs out of fuel, the SiNCs disassemble. The lifetime of the assemblies is controlled by the amount of fuel added. As an application of the transient supramolecular material, we demonstrate that the platform can be used to control the delayed uptake of the nanocrystals by mammalian cells.
Nano–silica functionalized with thiol–based dendrimer as a host for gold nanoparticles: An efficient and reusable catalyst for chemoselective oxidation of alcohols
Authors: Haghshenas Kashani Sara , Landarani‐Isfahani Amir , Moghadam Majid , Tangestaninejad Shahram , Mirkhani Valiollah , Mohammadpoor‐Baltork Iraj
Published: July 2018

In this paper, we present the synthesis of Au nanoparticles supported on nanosilica thiol based dendrimer, nSTDP. The catalyst was prepared by reduction of HAuCl4 with NaBH4 in the presence of nSTDP. The resulting Aunp–nSTDP materials were characterized by FT–IR and UV–vis spectroscopic methods, SEM, TEM, TGA, XPS and ICP analyses. The characterization of the catalyst showed that Au nanoparticles with the size of 2–6 nm are homogeneously distributed on the nSTDP dendrimer with a catalyst loading of about 0.19 mmol/g of catalyst. The Aunp–nSTDP catalyst was used in the oxidation of alcohols with tert–butyl hydroperoxide (TBHP) as oxidant. The influence of vital reaction parameters such as solvent, oxidant and amount of catalyst on the oxidation of alcohols was investigated. These reactions were best performed in an acetonitrile/water mixture (3:2) in the presence of 0.76 mol% of the catalyst on the basis of the Au content at 80 °C under atmospheric pressure of air to afford the desired products in high yields (80–93% for benzyl alcohols). The Aunp–nSTDP catalyst exhibited a high selectivity toward the corresponding aldehyde and ketone (up to 100%). Reusabiliy and stability tests demonstrated that the Aunp–nSTDP catalyst can be recycled with a negligible loss of its activity. Also this catalytic exhibited a good chemoselectivity in the oxidation of alcohols.
Copper Schiff base complex immobilized on silica‐coated Fe3O4 nanoparticles: a recoverable and efficient catalyst for synthesis of polysubstituted pyrroles
Authors: Hamrahian Seyedeh Aghigh , Rakhtshah Jamshid , Mousavi Davijani Seyedeh Mohadeseh , Salehzadeh Sadegh
Published: July 2018

In this work, a copper Schiff base complex immobilized on silica‐coated Fe3O4 nanoparticles is synthesized, and studied as a highly efficient, recyclable, green and heterogeneous catalyst for the preparation of polysubstituted pyrroles under solvent‐free and mild conditions. This new catalyst was characterized by different techniques, such as Fourier transform infrared (FT‐IR), X‐ray powder diffraction (XRD), field‐emission scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), inductively coupled plasma (ICP) and vibrating sample magnetometry (VSM). The simple and environmentally one‐pot multicomponent condensation of nitromethane, an aryl aldehyde, a 1,3‐dicarbonyl compound and an amine in the presence of above catalyst affords the title compounds at room temperature. At the end, we compared the results for the synthesis of polysubstituted pyrroles in the presence of our nanocatalyst with previously reported catalysts in the literature.
Vitamin B12 supported on graphene oxide: As a bio‐based catalyst for selective aerobic oxidation of alcohols
Authors: Shaabani Ahmad , Rashidi Vahid Adina , Shaabani Shabnam , Mohammadian Reza , Nazeri Mohammad Taghi , Keramati Nejad Mina
Published: July 2018

The environmental impact of chemical processes has now opened new windows of opportunity for bio‐based catalysts. In this paper a highly active bio‐based catalyst of vitamin B12 supported on graphene oxide nanosheets is reported for the selective aerobic oxidation of alcohols to the corresponding carbonyl compounds. Operational simplicity, mild reaction conditions, high yield and selectivity, non‐hazardous nature, commercial availability and affordability are the main advantages of this novel catalytic system.
MoP/Al2O3 as a novel catalyst for sulfur‐resistant methanation
Authors: Wang Baowei , Zhao Jun , Meng Dajun , Li Zhenhua , Xu Yan , Ma Xinbin
Published: July 2018

We reported γ‐alumina supported molybdenum phosphide (MoP) catalysts as a novel catalyst for sulfur‐resistant methanation reaction. The precursors of the catalyst were prepared by impregnation method and the effect of reduction temperatures (550 °C, 600 °C, 650 °C) of the precursors for sulfur‐resistant methanation was examined. The results indicated catalyst obtained by lower reduction temperature delivered better sulfur‐resistant methanation performance. Meanwhile, the influence of H2/CO ratios and H2S content was also investigated. The results indicated that high H2/CO ratio and low H2S content was favorable for methanation of MoP catalysts. The catalysts were characterized by N2 adsorption–desorption, XRD, XPS and TEM. The results confirmed that the MoP phase was formed on all the catalysts and the physicochemical properties of the samples influenced the performance for sulfur‐resistant methanation.
Poly(Ethylene Glycol)‐Crosslinked Poly(Vinyl Pyridine)‐based Gel Polymer Electrolytes
Authors: Shin Inseop , Lee Kukjoo , Kim Eunsoo , Kim Tae‐Hyun
Published: July 2018

A series of poly(ethylene glycol) (PEG)‐crosslinked poly(vinylpyridine)s (PVPs)—with PVP serving as the polymer backbone, and PEG side chain of the PVP as the ionic conductor and crosslinker—were developed as novel gel polymer electrolytes. These PEG‐crosslinked PVPs combined the advantages of the pendant PEG as ionic conductors on the polymer side chains with the thermomechanically stable PVPs, and showed self‐standing film‐forming properties without the use of any support. The composition with a pyridine:PEG weight ratio of 45:1 and an ethylene oxide:LiTFSI weight ratio of 10:1, denoted as PVP (45:1)–[10:1], showed a high ionic conductivity of over 1.34 × 10−5 S/cm at 25°C, and 2.94 × 10−4 S/cm at 80°C. These properties showed the PEG‐crosslinked PVPs to be promising candidate materials as gel polymer electrolytes for lithium‐ion batteries.
Enhanced Cleavage at Abasic Sites within Clustered Lesions in Nucleosome Core Particles
Authors: Yang Kun , Greenberg Marc M.
Published: July 2018

Clustered lesions are a hallmark of γ‐radiolysis, but are produced by other damaging agents as well. Bistranded clustered lesions are precursors to double‐strand breaks and are challenging to repair, thus making them an especially deleterious form of DNA damage. An abasic site (AP) is an alkaline‐labile lesion frequently present in clustered lesions. Strand scission at an AP site is accelerated ≈100‐fold in nucleosome core particles (NCPs). We examined how AP reactivity was affected within clustered lesions in NCPs. The rate constant of strand scission is increased as much as 2.5‐fold in the presence of a proximal abasic site or thymidine glycol in the complementary strand. A proximal mispair has a similar effect on AP reactivity. Increased AP reactivity within a clustered lesion correlates with decreased UV melting temperatures of the corresponding duplexes compared to one containing an isolated abasic site. However, the thermodynamics of duplex melting do not correlate with AP reactivity within different clustered lesions. Overall, increased AP reactivity within clustered lesions is attributed to greater access of histone proteins to the lesion due to decreased duplex stability.
Hybrid Molecular Container Based on Glycoluril and Triptycene: Synthesis, Binding Properties, and Triggered Release
Authors: Liu Wenjin , Lu Xiaoyong , Xue Weijian , Samanta Soumen K. , Zavalij Peter Y. , Meng Zihui , Isaacs Lyle
Published: July 2018

We designed and synthesized a “hybrid” molecular container 1, which is structurally related to both cucurbit[n]uril (CB[n]) and pillar[n]arene type receptors. Receptor 1 was fully characterized by 1H NMR, 13C NMR, IR, MS and X‐ray single crystal diffraction. The self‐association behavior, host–guest recognition properties of 1, and the [salt] dependence of Ka were investigated in detail by 1H NMR and isothermal titration calorimetry (ITC). Optical transmittance and TEM measurements provide strong evidence that receptor 1 undergoes co‐assemble with amphiphilic guest C10 in water to form supramolecular bilayer vesicles (diameter 25.6±2.7 nm, wall thickness ≈3.5 nm) that can encapsulate the hydrophilic anticancer drug doxorubicin (DOX) and the hydrophobic dye Nile red (NR). The release of encapsulated DOX or NR from the vesicles can be triggered by hexamethonium (8 c) or spermine (10) which leads to the disruption of the supramolecular vesicles.
Redox‐Active Chiroptical Switching in Mono‐ and Bis‐Iron Ethynylcarbo[6]helicenes Studied by Electronic and Vibrational Circular Dichroism and Resonance Raman Optical Activity
Authors: Shen Chengshuo , Srebro‐Hooper Monika , Weymuth Thomas , Krausbeck Florian , Navarrete Juan T. López , Ramírez Francisco J. , Nieto‐Ortega Belén , Casado Juan , Reiher Markus , Autschbach Jochen , Crassous Jeanne
Published: July 2018

Introducing one or two alkynyl–iron moieties onto a carbo[6]helicene results in organometallic helicenes (2 a,b) that display strong chiroptical activity combined with efficient redox‐triggered switching. The neutral and oxidized forms have been studied in detail by electronic and vibrational circular dichroism, as well as by Raman optical activity (ROA) spectroscopy. The experimental results were analyzed and spectra were assigned with the help of first‐principles calculations. In particular, a recently developed method for ROA calculations under resonance conditions has been used to study the intricate resonance effects on the ROA spectrum of mono‐iron ethynylhelicene 2 a.