bluuebunny/crossref_metadata_2025 huggingface dataset:
OCIO, REDES SOCIALES Y ESTUDIANTES ESPAÑOLES
Authors: Sanz Arazuri Eva , Alonso Ruiz Rosa Ana , Saénz de Jubera Ocón Magdalena , Ponce de León Elizondo Ana , Valdemoros San Emeterio Mª Ángeles
Published: June 2018

Las redes sociales se constituyen en modelo de comunicación de referencia para la juventud española y se erigen como la actividad de ocio digital juvenil preferente. El objetivo de este estudio fue determinar las actividades principales de ocio más publicadas en las redes sociales por los jóvenes españoles, identificando las características sociodemográficas asociadas. La muestra estuvo constituida por 1764 estudiantes españoles de educación secundaria postobligatoria que representaron a todas las áreas territoriales del estado español. Se registraron sus actividades de ocio más importantes, el número y tipo de estas publicadas en las redes sociales, el sexo del estudiante y las áreas territoriales a las que pertenecían los participantes. El 64.2% de los estudiantes españoles de secundaria postobligatoria publica en las redes sociales la práctica de al menos una de sus tres actividades de ocio principales. Las fiestas y celebraciones se erigen como el ocio más difundido.Existen diferencias significativas en cuanto al sexo y área geográfica de residencia. Las mujeres comparten más su ocio prioritario en las redes sociales. Quienes dan importancia relevante al turismo, las fiestas y las actividades digitales, son los que más publican su ocio. Las conclusiones ofrecen claves de intervención educativa en un escenario social prioritario para la juventud y resultan de gran utilidad para los agentes implicados en la promoción del ocio entre los jóvenes españoles.
TREINTA AÑOS DE EVALUACIÓN DE CENTROS EDUCATIVOS EN ESPAÑA
Authors: Tiana Ferrer Alejandro
Published: June 2018

por la calidad de la educación, que renovó el discurso pedagógico y llevó aparejado un refuerzo de las actividades de evaluación, al ser esta entendida como un instrumento clave para producir la anhelada mejora. Fue en ese contexto en el que comenzó a construirse en España una política común de evaluación de los centros educativos, considerados el lugar donde se encarna la tarea educativa y se debe producir la mejora. Dicha política fue cambiando a lo largo del tiempo, en función de los cambios registrados en la orientación política general, el reparto de competencias en materia de educación y las iniciativas concretas de los diversos agentes y administraciones. En este artículo se analizan las características de las políticas desarrolladas en los últimos treinta años para evaluar los centros docentes, así como de las prácticas en que se han traducido. El enfoque adoptado se inscribe en la política de la educación, centrándose en los planteamientos adoptados y las prácticas desarrolladas por las diversas administraciones. Para ello se ha recurrido a la identificación y consulta de obras académicas y de investigación, informes oficiales, normas legales y «literatura gris». Tras llevar a cabo dicho análisis, el trabajo concluye que la política adoptada a lo largo de estos treinta años se ha caracterizado por los avances y retrocesos, los cambios de orientación, la falta de coherencia entre las intenciones y la práctica y la insuficiencia de las acciones desarrolladas.
Association Analysis of Piping Materials of an Offshore Structure Using Big Data Technology
Authors: Park Sung-Woo , Roh Myung-II , Oh Min-Jae , Kim Seong-Hoon
Published: June 2018

Various types of data are produced by the shipbuilding and offshore industry. As the number of ships and offshore structures that were built over time increased, an enormous amount of data, called big data, had to be handled. However, it is difficult to handle effectively such big data with the existing methodology for data storage and processing. Therefore, big data technology needs to be applied to the systems of shipyards, such as the product lifecycle management system. On the other hand, the construction of an offshore structure requires a lot of piping, and there are many materials as much as piping. For a shipyard that executes multiple projects at once, it is not easy to correlate so much piping material. A piping designer should check all materials based on his or her understanding of the design characteristics. However, depending on the maturity of the designer, it can be difficult to handle such large data manually; as a result, there can be errors in piping design. In this study, a big data framework applicable to the shipyard is proposed and used for the analysis. That is, the association analysis of piping materials of an offshore structure is performed based on the big data framework that can process a large amount of data to assist piping designers. As an application, after analyzing the material data for one offshore structure, the applicability of this study was evaluated through the results. We believe this study can help piping designers.

1. Introduction

1.1. Research background

One of the fastest growing technologies in several industries is big data and its applications. Big data can be defined as a series of computer technologies that can store, process, and manage much more data than were handled before. From this next-generation technology and architecture, data can be easily gathered and analyzed. Big data is often characterized by three different words that start with "V" (Beyer 2011). The first "V" word is volume and it refers to a large volume of data. The next "V" word is velocity, referring to how fast the data processing is. Usually, it should be enough to obtain the result of the analysis in real time without any delay. Also, there are many types of processable data, which can also be unstructured; hence, the last "V" word stands for variety. Recently, two more words are used because we cannot define the characteristics of big data with only three words. One is "veracity"; another is "value." Veracity is for selecting high-quality data from all of it (Villanova University 2018) and value is the main reason why people use big data technology (Mauro et al. 2013). Table 1 describes the characteristics of big data briefly.
Una metodología multivariante versus una metodología tradicional en la identificación y clasificación del paisaje
Authors: Alcántara Manzanares Jorge , Muñoz Álvarez Jesús Miguel
Published: June 2018

El objetivo de este estudio ha sido validar una identificación de tipos de paisaje desarrollada gracias a un método multivariante de clasificación (TWINSPAN), tomando como ámbito de estudio la provincia de Huelva (Andalucía, España), mediante su comparación con una identificación realizada utilizando métodos no estadísticos. Para ello se eligió la identificación de tipos de paisajes del Atlas de los Paisajes de España Sanz. El análisis comparado muestra un grado de similitud óptimo entre ambas. Esto respalda la validez del método multivariante, que además presenta una serie de ventajas frente al tradicional, aunque probablemente la excelencia se consiga mediante la combinación de ambos
Portrait de la pratique évaluative des troubles du comportement des psychoéducateurs dans les écoles primaires au Québec
Authors: Bégin Jean-Yves , Massé Line , Couture Caroline , Villeneuve Madeleine
Published: June 2018

En milieu scolaire, le psychoéducateur est appelé à jouer un rôle clef dans l’évaluation des difficultés d’adaptation vécues par les élèves, notamment sur le plan comportemental. À l’heure actuelle, peu d’informations sont disponibles sur ce que font les psychoéducateurs lorsqu’ils mènent une évaluation dans le cadre de leur fonction. Cette étude descriptive vise donc à dresser un portrait de la pratique évaluative des psychoéducateurs dans les écoles primaires au Québec en considérant les différences pouvant exister selon leur niveau de formation universitaire et leur région d’appartenance. Le devis de recherche mixte allie des données provenant de six groupes de discussion (n total de participants = 34), d’entrevues téléphoniques (n = 21) et des données issues de questionnaires (N = 159). Les résultats indiquent que la pratique évaluative des psychoéducateurs est somme toute homogène en considérant le niveau de formation et la région d’appartenance. De plus, ils démontrent que les psychoéducateurs rapportent avoir une pratique évaluative qui correspond d’assez près aux recommandations de pratiques dans le domaine de l’évaluation en milieu scolaire. Enfin, les résultats mettent en lumière les besoins des psychoéducateurs et les contraintes auxquels ils font face en exercice par rapport à l’évaluation et qui peuvent être causés par des enjeux d’identité professionnelle.
Le vécu partagé, une notion fondatrice qui appelle un consensus à actualiser
Authors: Daigle Sonia , Couture Caroline , Renou Marcel , Potvin Pierre , Rousseau Michel
Published: June 2018

Au Québec, à compter des années 1990, de nombreuses professions du domaine psychosocial font face à la nécessité de résoudre différents enjeux relatifs à la spécificité de leur contribution professionnelle. Très peu de connaissances scientifiques ont été produites relativement aux interrelations entre la spécificité identitaire des psychoéducateurs et des psychoéducatrices et le vécu partagé, une notion considérée comme fondatrice de cette discipline universitaire à vocation professionnelle. Dans quelle mesure le vécu partagé est-il encore le fondement de la spécificité identitaire des psychoéducateurs et des psychoéducatrices? Afin d’apporter des éléments de réponse à cette question, un devis de recherche mixte séquentiel exploratoire a été utilisé. Des entrevues semi-structurées menées auprès de 21 membres de l’Ordre des psychoéducateurs et psychoéducatrices du Québec (OPPQ) ont conduit à l’élaboration d’un questionnaire traitant spécifiquement de la psychoéducation, rempli par 462 membres. La majorité d’entre eux soutiennent que le devenir de leur profession est liée à l’affirmation de sa singularité, qu’ils considèrent être le vécu partagé. Les résultats obtenus montrent que le vécu partagé dont les membres de l’OPPQ font usage dans l’exercice de leur profession ne correspond pas aux éléments constitutifs de sa définition initiale. Ils révèlent que la singularité de l’intervention psychoéducative ne repose plus sur la seule notion de vécu partagé. En bref, le consensus qui existait à l’effet de considérer le vécu partagé comme étant le socle de l’intervention psychoéducative apparait en voie de rupture.
La perception de parents d’enfants et d’adolescents dysphasiques de 2 à 17 ans quant à l’accès aux services orthophoniques au Québec
Authors: Michallet Bernard , Mongrain Julie , Duchesne Louise
Published: June 2018

Les difficultés vécues par les enfants et les adolescents dysphasiques, bien démontrées dans les écrits scientifiques, sont persistantes et rendent leur parcours et celui de leurs parents parsemés d’embûches. Cette étude vise à connaître la perception des parents à l’égard de l’accès aux services orthophoniques offerts au Québec pour leur enfant dysphasique âgé de 2 à 17 ans, et ce, dans les établissements de santé, scolaires ou privés. 377 parents à travers le Québec ont répondu à un questionnaire en ligne. L’analyse de leurs réponses permet de faire certains constats. D’abord, l’accès aux services orthophoniques visant le dépistage, l’identification, l’évaluation et l’intervention auprès des enfants et adolescents dysphasiques semble limité dans le réseau public. Les parents soulignent également que les services ne se poursuivent généralement pas dans une transition harmonieuse entre les établissements de santé et le milieu scolaire. De plus, la grande variabilité observée quant aux délais d’accès aux services orthophoniques selon les régions du Québec est difficilement compréhensible. Enfin, pour remédier à l’offre de services orthophoniques limitée dans les établissements publics, une majorité des répondants a fait appel aux services orthophoniques privés et a déboursé des sommes importantes. Les résultats de l’étude suggèrent que les principes promus dans le Plan d’accès ministériel aux services pour les personnes ayant une déficience du Gouvernement du Québec, tels que l’équité, la réponse adéquate aux besoins des personnes ayant une déficience et de leur famille, l’intégration et la complémentarité des services, ne semblent actuellement pas respectés.
Remote sensing tree classification with a multilayer perceptron
Authors: Sumsion G Rex , Bradshaw Michael S , Hill Kimball T , Pinto Lucas D G , Piccolo Stephen R ,   BYU Bioinformatics Research Group (BRG)
Published: June 2018

To accelerate scientific progress on remote tree classification—as well as biodiversity and ecology sampling—The National Institute of Science and Technology created a community-based competition where scientists were invited to contribute informatics methods for classifying tree species and genus using crown-level images of trees. We predicted tree species and genus at the pixel level using hyperspectral and LIDAR observations. We compared three algorithms that have been implemented extensively across a broad range of research applications: support vector machines, random forests, and multilayer perceptron. At the pixel level, the multilayer perceptron algorithm predicted species or genus with high accuracy (92.7 and 95.9%, respectively) on the training data and performed better than the other algorithms (85.8-93.5%). This indicates promise for the use of the MLP algorithm for tree-species classification and coincides with a growing body of research in which neural network-based algorithms outperform other types of classification algorithms for machine vision. To aggregate patterns across the images, we used an ensemble approach that averages the pixel-level outputs of the MLP algorithm to predict species at the crown level. The accuracy of these predictions on the test set was 68.8% for species.
The eukaryotic bell-shaped temporal rate of DNA replication origin firing emanates from a balance between origin activation and passivation
Authors: Arbona Jean-Michel , Goldar Arach , Hyrien Olivier , Arneodo Alain , Audit Benjamin
Published: June 2018

The time-dependent rate I(t) of origin firing per length of unreplicated DNA presents a universal bell shape in eukaryotes that has been interpreted as the result of a complex time-evolving interaction between origins and limiting firing factors. Here, we show that a normal diffusion of replication fork components towards localized potential replication origins (p-oris) can more simply account for the I(t) universal bell shape, as a consequence of a competition between the origin firing time and the time needed to replicate DNA separating two neighboring p-oris. We predict the I(t) maximal value to be the product of the replication fork speed with the squared p-ori density. We show that this relation is robustly observed in simulations and in experimental data for several eukaryotes. Our work underlines that fork-component recycling and potential origins localization are sufficient spatial ingredients to explain the universality of DNA replication kinetics.
Exercise Behavior, Facilitators and Barriers among Socio-economically Disadvantaged African American Young Adults
Authors: Kosma Maria , R. Buchanan David
Published: June 2018

Background: Although exercise participation has numerous benefits among young adults, socio-economically disadvantaged ethnic minorities tend to be less active than their White counterparts of higher SES. Instead of relying on logical positivism in exercise promotion, a phronetic (humanistic) approach may better assist with understanding exercise behavior. Objective: The study purpose was to examine the exercise behavior and qualitatively distinct exercise values (e.g., activity and inactivity reasons) among socio-economically disadvantaged African American young adults. Method: This was a phronetic, qualitative study among 14 African American young adults (Mage = 32.97 years old ±14.13), who attended General Educational Development classes in an inner-city learning center. An in-depth and dialogical interview process was conducted regarding exercise behavior, positive and negative exercise experiences, reasons for exercise participation or not, exercise behavior of participants’ peers and significant others, and neighborhood safety. Results: Only three men met the minimum aerobic exercise recommendations and their main activity was basketball. Three individuals were somewhat active, while the rest of the participants were inactive. Based on the phronetic, thematic analysis, two themes emerged. Exercise facilitators included enjoyment (from skill and fitness development in a playful setting), health improvement, weight loss and toned physique, and utilitarian purpose (i.e., karate to work for campus security). Exercise barriers included time constraints and other priorities (school, work, caretaking), injuries, accessibility and cost issues, safety issues (unsafe neighborhoods), personality (lack of motivation and self-discipline), and undesirable results on appearance and performance. Conclusion: Exercise promoters should emphasize: a) playful, culturally meaningful, and socially supported activities to increase fitness, skill development, and enjoyment; b) policy change via the provision of parental leave for both parents; c) safe and accessible exercise settings, especially among women of lower SES; d) information about safe exercises and injury recovery; and e) fit and healthy physiques for personal fulfilment and enjoyment.
Influences of Athletic Footwear on Ground Reaction Forces During A Sidestep Cutting Maneuver on Artificial Turf
Authors: R. Gdovin Jacob , C. Williams Charles , J. Wilson Samuel , A. Luginsland Lauren , Allen Charles R. , Wade Chip , Garner III John C.
Published: June 2018

Background: Recreational athletes can select their desired footwear based on personal preferences of shoe properties such as comfort and weight. Commonly worn running shoes and cleated footwear with similar stud geometry and distribution are worn when performing sport-specific tasks such as a side-step cutting maneuver (SCM) in soccer and American football (hereafter, referred to as football). The effects of such footwear on injury mechanics have been documented with less being known regarding their effect on performance. Objective: The purpose of this study was to examine performance differences including peak ground reaction forces (pGRF), time-to-peak ground reaction forces (tpGRF) and the rate of force development (RFD) between football cleats (FB), soccer cleats (SOC), and traditional running sneakers (RUN) during the braking and propulsive phases of a SCM. Methodology: Eleven recreationally active males who participated in football and/or soccer-related activities at the time of testing completed the study. A 1 x 3 [1 Condition (SCM) x 3 Footwear (RUN, FB, SOC)] repeated measures ANOVA was utilized to analyze the aforementioned variables. Results: There were no significant differences (p > 0.05) between footwear conditions when comparing pGRF, tpGRF, or RFD in either the braking or propulsive phases. Conclusion: The results suggest that the studded and non-studded footwear allowed athletes to generate similar forces over a given time frame when performing a SCM.
Cytotoxic effects of zinc oxide nanoparticles on cyanobacteriumSpirulina (Arthrospira) platensis
Authors: Djearamane Sinouvassane , Lim Yang Mooi , Wong Ling Shing , Lee Poh Foong
Published: June 2018

Background

The extensive usage of zinc oxide nanoparticles (ZnO NPs) in industrial and consumer products raises the risk of releasing their residues into the aquatic environment. The presence of ZnO NPs in the aquatic environment could potentially cause cytotoxic effects on aquatic organisms. Thus, investigating the cytotoxic effects of ZnO NPs on microalgae, which form the base for the food web of aquatic biota, is essential to gain information regarding the ecotoxicological effects of metallic oxide nanoparticles in the aquatic ecosystem. Therefore, the present study has investigated in detail the assorted cytotoxic effects of ZnO NPs onS. platensisusing various concentrations of ZnO NPs (10–200 mg/L) from 6 to 96 h to explore the dose- and time-dependent cytotoxic effects.

Methods

The cytotoxic effects were all assessed through quantification of loss in cell viability, reduction in biomass and decrease in photosynthetic pigments such as chlorophyll-a, carotenoids and phycocyanin. The surface interactions of nanoparticles and the subsequent morphological alterations on algal cells were examined by optical and scanning electron microscopy (SEM). The intracellular alterations of algal cells were studied using transmission electron microscopy. Furthermore, Fourier transformed infrared (FTIR) spectrum was obtained to investigate the involvement of algal surface biomolecules in surface binding of ZnO NPs on algal cells.

Results

The treatment of ZnO NPs onS. platensisexhibited a typical concentration- and time-dependent cytotoxicity. Results showed a significant (p < 0.05) cytotoxicity from 24 h onwards for all tested concentrations of ZnO NPs. The maximum cytotoxicity on algal cells was achieved at 96 h of exposure to ZnO NPs. In comparison with control, the algal cells that interacted with 200 mg/L of ZnO NPs for 96 h showed 87.3 ± 1% loss in cell viability, 76.1 ± 1.7% reduction in algal biomass, 92.5 ± 2.2%, 76.2 ± 2.2% and 74.1 ± 3.4% decrease in chlorophyll-a, carotenoids and phycocyanin contents respectively. Our study confirmed the cytotoxicity of ZnO NPs through the algal growth inhibition with 72 h EC10and EC50values of 1.29 and 31.56 mg/L, respectively. The microscopic examinations of the algal cells that interacted with ZnO NPs showed severe cell membrane and intracellular damage. The SEM EDX spectrum of ZnO NPs treated algal biomass evidenced the surface accumulation of zinc in the biomass. Finally, the FTIR spectrum confirmed the involvement of amino, hydroxyl and carboxylic groups of algal cell wall in the surface interaction of ZnO NPs on the algal cells.

Discussion

The results showed that the treatment of ZnO NPs onS. platensistriggered substantial cytotoxicity and caused cell death. Hence,S. platensiscould be potentially used as a bioindicator for testing toxicity of ZnO NPs in aquatic environment.
Comparing the biomechanical characteristics between squat and standing serves in female table tennis athletes
Authors: Yu Changxiao , Shao Shirui , Baker Julien S. , Gu Yaodong
Published: June 2018

Background

The table tennis serve involves complex spatial movements combined with biomechanial characteristics. Although the differences in lower-limb biomechanial characteristics to a great extent influence the translational and spinning velocity of the ball when using the different styles of table tennis serve, few researchers have studied their mechanics. Therefore, the aim of this study was to investigate the differences in lower-limb activity between the squat and standing serves during a table tennis short serve.

Methods

Ten advanced female table tennis participants performed a squat serve and standing serve in random order. A Vicon motion analysis system and a Novel Pedar insole plantar pressure measurement system were used to record kinematics and kinetics data, respectively.

Results

Key findings from the study were that the squat serve not only showed significantly larger hip and knee flexion, as well as ankle dorsiflexion, it also showed significantly larger hip adduction and external knee rotation, with larger changing angular rate of the lower limb joints in the sagittal and the transverse planes when the two serving styles were compared. In addition, the force-time integral (FTI) was higher in the rear foot area for the standing serve.

Discussion

The results demonstrated that the squat serve needs higher lower limb drive during a table tennis short serve compared with a standing serve. These biomechanical considerations may be beneficial for table tennis athletes and coaches as a method of optimizing performance characteristics during both competition and training.
Exploring constructs of well-being, happiness and quality of life
Authors: Medvedev Oleg N. , Landhuis C. Erik
Published: June 2018

Background

Existing definitions of happiness, subjective well-being, and quality of life suggest conceptual overlap between these constructs. This study explored the relationship between these well-being constructs by applying widely used measures with satisfactory psychometric properties.

Materials and Methods

University students (n = 180) completed widely used well-being measures including the Oxford Happiness Questionnaire (OHQ), the World Health Organization Quality of Life Questionnaire, the Satisfaction with Life Scale, and the Positive and Negative Affect Scale. We analyzed the data using correlation, regression, and exploratory factor analysis.

Results

All included well-being measures demonstrated high loadings on the global well-being construct that explains about 80% of the variance in the OHQ, the psychological domain of Quality of Life and subjective well-being. The results show high positive correlations between happiness, psychological and health domains of quality of life, life satisfaction, and positive affect. Social and environmental domains of quality of life were poor predictors of happiness and subjective well-being after controlling for psychological quality of life.

Conclusion

Together, these data provide support for a global well-being dimension and interchangeable use of terms happiness, subjective well-being, and psychological quality of life with the current sample and measures. Further investigation with larger heterogeneous samples and other well-being measures is warranted.
Occupational health and safety characteristics of agricultural workers in Adana, Turkey: a cross-sectional study
Authors: Okyay Ramazan Azim , Tanır Ferdi , Ağaoğlu Pelin Mutlu
Published: June 2018

Background

Among agricultural workers, especially in the seasonal migratory ones, housing and hygiene related issues, occupational accidents, low levels of education, poverty and absence of social security problems emerge as significant public health problems. This study aims to compare migrant-seasonal workers (MSWs) and resident agricultural workers (RAWs) in terms of socio-demographic characteristics and occupational health and safety in Adana, one of Turkey’s most important agricultural cities.

Methods

This cross-sectional study was conducted on RAWs and MSWs, aged 15–65, operating in the province of Adana. The calculated sample sizes for both MSWs and RAWs were distributed using stratified simple random sampling to five districts of Adana.

Results

The mean age of the 798 participating agricultural workers was 34.6 ± 14.2. Of the RAWs, 78.8% and of the MSWs 57.0% were male; 5.8% of RAWs and 32.8% of MSWs were illiterate. The mean number of people in the households of the participating workers was 5.1 for RAWs and 6.6 for MSWs. Of the RAWs, 20.5% were not covered by any social security scheme while this percentage was 35.1% in MSWs. RAWs worked 9.9 h a day while MSWs worked 10.9 h a day. Of the agricultural workers, 12.9% had injuries caused by occupational accidents.

Discussion

Agricultural workers, who are a large part of Turkey’s economically active population, do not have healthy and safe working conditions. New regulations in the fields of social security, record keeping, monitoring, supervision, education and occupational health have been implemented recently to solve these problems. Despite the recent improvements there are still some problematic issues in the auditing of the necessary practices.
N-acetylcysteine protects against motor, optomotor and morphological deficits induced by 6-OHDA in zebrafish larvae
Authors: Benvenutti Radharani , Marcon Matheus , Reis Carlos G. , Nery Laura R. , Miguel Camila , Herrmann Ana P. , Vianna Monica R.M. , Piato Angelo
Published: June 2018

Background

Parkinson’s disease (PD) is the second most common neurodegenerative disorder. In addition to its highly debilitating motor symptoms, non-motor symptoms may precede their motor counterparts by many years, which may characterize a prodromal phase of PD. A potential pharmacological strategy is to introduce neuroprotective agents at an earlier stage in order to prevent further neuronal death.N-acetylcysteine (NAC) has been used against paracetamol overdose hepatotoxicity by restoring hepatic concentrations of glutathione (GSH), and as a mucolytic in chronic obstructive pulmonary disease by reducing disulfide bonds in mucoproteins. It has been shown to be safe for humans at high doses. More recently, several studies have evidenced that NAC has a multifaceted mechanism of action, presenting indirect antioxidant effect by acting as a GSH precursor, besides its anti-inflammatory and neurotrophic effects. Moreover, NAC modulates glutamate release through activation of the cystine-glutamate antiporter in extra-synaptic astrocytes. Its therapeutic benefits have been demonstrated in clinical trials for several neuropsychiatric conditions but has not been tested in PD models yet.

Methods

In this study, we evaluated the potential of NAC to prevent the damage induced by 6-hydroxydopamine (6-OHDA) on motor, optomotor and morphological parameters in a PD model in larval zebrafish.

Results

NAC was able to prevent the motor deficits (total distance, mean speed, maximum acceleration, absolute turn angle and immobility time), optomotor response impairment and morphological alterations (total length and head length) caused by exposure to 6-OHDA, which reinforce and broaden the relevance of its neuroprotective effects.

Discussion

NAC acts in different targets relevant to PD pathophysiology. Further studies and clinical trials are needed to assess this agent as a candidate for prevention and adjunctive treatment of PD.
A Description of a Noninvasive Surgical Training Pathway Using Translational Tools to Teach Intracoelomic Implantation of Acoustic Transmitters in Fish
Authors: Brosnan Ian G. , Williams Wendy O. , Sanders George E. , McGarry Louise P. , Greene Charles H.
Published: May 2018

Researchers engaged in surgical implantation of acoustic transmitters into fish must receive adequate and appropriate training to ensure the welfare of their subjects and the quality of the data collected. Increasingly, researchers are being encouraged to partner with veterinarians to improve training and to consider the principles of animal welfare in training. Here, we describe a five-stage training pathway, including implementation of new training tools (the Translational Training Tools and field certification), that was developed collaboratively by researchers and veterinarians and addresses the “three Rs” of animal welfare in the context of surgical training. The three Rs include animal replacement, reduction of the number of animals used, and refinement of techniques to decrease or eliminate pain or distress. The Translational Training Tools, described in the context of the training pathway, use tools as replacement models during training to reduce the number of animals used and allow for refinement of surgical skills prior to working on live animals. The purpose of this paper is to document the Translational Training Tools and the training pathway, which will be useful in developing de novo protocols for review by Institutional Animal Care and Use Committees and similar bodies.
Tuning of Calcite Crystallographic Orientation to Support Brachiopod Lophophore
Authors: Cusack Maggie , Chung Peter , Zhu Wenzhong , Endo Kazuyoshi
Published: May 2018

Organisms exert exquisite control on mineral formation by tuning structural and material properties to meet functional requirements. Brachiopods are sessile marine organisms that filter feed via a large lophophore which is supported by a delicate calcite loop that grows from the inner surface of the shell. How does the loop support the weight of the large lophophore? Electron backscatter diffraction (EBSD) and nanoindentation analyses of the loop as it emerges from the shell of Laqueus rubellus reveal that calcite fiber crystallography generates asymmetry in the material properties of the structure. In the core of the emergent loop, the fibers are short and kernel‐like. Either side of the core, the long fibers have a different crystallographic orientation and resultant material properties. fibers on the anterior, load‐bearing side, are harder (H = 3.76 ± 0.24 GPa) and less stiff (E = 76.87 ± 4.87 GPa) than the posterior (H = 3.48 ± 0.31 GPa, E = 81.79 ± 5.33 GPa). As a consequence of the asymmetry in the material properties, the loop anterior may be more flexible under load. The brachiopod strategy of tuning crystallographic orientation to confer spatially determined material properties is attractive for additive manufacturing of synthetic materials that have complex heterogeneous material property requirements.
Layered P2‐Type K0.65Fe0.5Mn0.5O2 Microspheres as Superior Cathode for High‐Energy Potassium‐Ion Batteries
Authors: Deng Tao , Fan Xiulin , Chen Ji , Chen Long , Luo Chao , Zhou Xiuquan , Yang Junhe , Zheng Shiyou , Wang Chunsheng
Published: May 2018

Potassium‐ion batteries have been regarded as the potential alternatives to lithium‐ion batteries (LIBs) due to the low cost, earth abundance, and low potential of K (−2.936 vs standard hydrogen electrode (SHE)). However, the lack of low‐cost cathodes with high energy density and long cycle life always limits its application. In this work, high‐energy layered P2‐type hierarchical K0.65Fe0.5Mn0.5O2 (P2‐KFMO) microspheres, assembled by the primary nanoparticles, are fabricated via a modified solvent‐thermal method. Benefiting from the unique microspheres with primary nanoparticles, the K+ intercalation/deintercalation kinetics of P2‐KFMO is greatly enhanced with a stabilized cathodic electrolyte interphase on the cathode. The P2‐KFMO microsphere presents a highly reversible potassium storage capacity of 151 mAh g−1 at 20 mA g−1, fast rate capability of 103 mAh g−1 at 100 mA g−1, and long cycling stability with 78% capacity retention after 350 cycles. A full cell with P2‐KFMO microspheres as cathode and hard carbon as anode is constructed, which exhibits long‐term cycling stability (>80% of retention after 100 cycles). The present high‐performance P2‐KFMO microsphere cathode synthesized using earth‐abundant elements provides a new cost‐effective alternative to LIBs for large‐scale energy storage.
Dynamic Photoswitching of Electron Energy Levels at Hybrid ZnO/Organic Photochromic Molecule Junctions
Authors: Wang Qiankun , Ligorio Giovanni , Diez‐Cabanes Valentin , Cornil David , Kobin Björn , Hildebrandt Jana , Nardi Marco Vittorio , Timpel Melanie , Hecht Stefan , Cornil Jérôme , List‐Kratochvil Emil J. W. , Koch Norbert
Published: May 2018

The functionality of interfaces in hybrid inorganic/organic (opto)electronic devices is determined by the alignment of the respective frontier energy levels at both sides of the heterojunctions. Controlling the interface electronic landscape is a key element for achieving favourable level alignment for energy and charge transfer processes. Here, it is shown that the electronic properties of polar ZnO surfaces can be reversibly modified using organic photochromic switches. By employing a range of surface characterization techniques combined with density functional theory calculations, it is demonstrated that self‐assembled monolayers (SAMs) of photochromic phosphonic acid diarylethenes (PA‐DAEs) can be employed to reversibly change the electronic properties of polar ZnO/SAM structures by light stimuli. The highest occupied molecular orbital level of PA‐DAE is raised by 0.7 eV and the lowest unoccupied one lowered by 0.9 eV, respectively, upon illumination by ultraviolet light and the levels shift back to their original position upon illumination by green light. The results thus provide a pathway to tailor hybrid interface electronic properties in a dynamic manner upon simple light illumination, which can be exploited to reversibly tune the electrical properties of photoswitchable (opto)electronic devices.
Natural Biomaterials for Corneal Tissue Engineering, Repair, and Regeneration
Authors: Palchesko Rachelle N. , Carrasquilla Santiago D. , Feinberg Adam W.
Published: May 2018

Corneal blindness is a major cause of vision loss, estimated to affect over 10 million people worldwide. Once impaired through clouding or shape change, the best treatment option for restoring vision is corneal transplantation using full or partial thickness cadaveric grafts. However, donor corneas are globally limited and face rejection and graft failure, similar to other transplanted organs. Thus, there is a need for viable alternatives to donor corneas in order to increase supply, reduce rejection, and to minimize variability in tissue quality. To address this, researchers have developed new materials and strategies to tissue engineer full or partial thickness cornea grafts in order to repair, regenerate, or replace the diseased cornea. This progress report first reviews the anatomy and physiology of the cornea to frame the biological requirements and discuss the injuries and diseases that necessitate the need fortransplantation, as well as the requirements for a suitable donor tissue alternative. This is followed by recent progress using naturally derived biomaterials including silk, collagen, amniotic membranes, and decellularized corneas. Finally, remaining challenges in the field as they relate to the biomaterials discussed are identified, and the future research directions that should result in further advances in restoring corneal vision are highlighted.
EGaIn‐Assisted Room‐Temperature Sintering of Silver Nanoparticles for Stretchable, Inkjet‐Printed, Thin‐Film Electronics
Authors: Tavakoli Mahmoud , Malakooti Mohammad H. , Paisana Hugo , Ohm Yunsik , Green Marques Daniel , Alhais Lopes Pedro , Piedade Ana P. , de Almeida Anibal T. , Majidi Carmel
Published: May 2018

Coating inkjet‐printed traces of silver nanoparticle (AgNP) ink with a thin layer of eutectic gallium indium (EGaIn) increases the electrical conductivity by six‐orders of magnitude and significantly improves tolerance to tensile strain. This enhancement is achieved through a room‐temperature “sintering” process in which the liquid‐phase EGaIn alloy binds the AgNP particles (≈100 nm diameter) to form a continuous conductive trace. Ultrathin and hydrographically transferrable electronics are produced by printing traces with a composition of AgNP‐Ga‐In on a 5 µm‐thick temporary tattoo paper. The printed circuit is flexible enough to remain functional when deformed and can support strains above 80% with modest electromechanical coupling (gauge factor ≈1). These mechanically robust thin‐film circuits are well suited for transfer to highly curved and nondevelopable 3D surfaces as well as skin and other soft deformable substrates. In contrast to other stretchable tattoo‐like electronics, the low‐cost processing steps introduced here eliminate the need for cleanroom fabrication and instead requires only a commercial desktop printer. Most significantly, it enables functionalities like “electronic tattoos” and 3D hydrographic transfer that have not been previously reported with EGaIn or EGaIn‐based biphasic electronics.
Dual Role of Vinyl Sulfonamides as N‐Nucleophiles and Michael Acceptors in the Enantioselective Synthesis of Bicyclic δ‐Sultams
Authors: Mulet Cristina , Escolano Marcos , Llopis Sebastián , Sanz Sergio , Ramírez de Arellano Carmen , Sánchez‐Roselló María , Fustero Santos , del Pozo Carlos
Published: May 2018

A new methodology for the synthesis of enantiomerically enriched bicyclic δ‐sultams is described, involving an initial organocatalytic intramolecular aza‐Michael reaction of vinyl sulfonamides bearing a conjugated ketone at a remote position. The resulting Michael adducts were then subjected to an intramolecular conjugate addition over the vinyl sulfone moiety, thus rendering the final bicyclic sultams containing two stereocenters. The key point of this strategy relies on the use of vinyl sulfonamides as both, nitrogen nucleophiles and Michael acceptors. The use of phosphazene‐derived bases avoided the racemization of the intermediate derivatives, rendering 6‐membered ring bicyclic δ‐sultams in enantiomerically enriched manner with a small erosion of enantiopurity. Anyway, after recrystallization, final sultams were obtained in almost enantiomerically pure form. Nevertheless, the enantioselective synthesis of either 5‐membered ring products or benzofused derivatives was found to be out of the scope of our strategy.

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Improved Processability and Efficiency of Colloidal Quantum Dot Solar Cells Based on Organic Hole Transport Layers
Authors: Aqoma Havid , Mubarok Muhibullah Al , Lee Wooseop , Hadmojo Wisnu Tantyo , Park Cheolwoo , Ahn Tae Kyu , Ryu Du Yeol , Jang Sung‐Yeon
Published: May 2018

High‐efficiency solid‐state‐ligand‐exchange (SSE) step‐free colloidal quantum dot photovoltaic (CQDPV) devices are developed by employing CQD ink based active layers and organic (Polythieno[3,4‐b]‐thiophene‐co‐benzodithiophene (PTB7) and poly(3‐hexylthiophene) (P3HT)) based hole transport layers (HTLs). The device using PTB7 as an HTL exhibits superior performance to that using the current leading organic HTL, P3HT, because of favorable energy levels, higher hole mobility, and facilitated interfacial charge transfer. The PTB7 based device achieves power conversion efficiency (PCE) of 9.60%, which is the highest among reported CQDPVs using organic HTLs. This result is also comparable to the PCE of an optimized device based on a thiol‐exchanged p‐type CQD, the current‐state‐of‐the‐art HTL. From the viewpoint of device processing, the fabrication of CQDPVs is achieved by direct single‐coating of CQD active layers and organic HTLs at low temperature without SSE steps. The experimental results and device simulation results in this work suggest that further engineering of organic HTL materials can open new doors to improve the performance and processing of CQDPVs.
Objective Realism and Joint Measurability in Quantum Many Copies
Authors: Bednorz Adam
Published: May 2018

In the standard quantum theory, one can measure precisely only a subset of the incompatible observables. It results in lack of a formal joint probability defining objective realism even if we accept nonlocal or certain faster‐than‐light interactions. Here, a construction of such realism extending the usual single‐copy description to many copies, partially analogous to familiar many worlds, is proposed. Failure of the standard single copy can be easily looked for experimentally. The copies should interact weakly at the macroscopic level, leading to effective collapse to a single identical pointer state. Experimental evidence for this conjecture could be obtained by detecting incomplete collapse in sequential measurements or finding deviations from the single‐copy Born rule when observing simple quantum systems.
Eine strukturelle Evaluierung medizinalchemischer Strategien gegen Wirkstoffresistenzen
Authors: Agnello Stefano , Brand Michael , Chellat Mathieu F. , Gazzola Silvia , Riedl Rainer
Published: May 2018

Das natürliche Phänomen der Wirkstoffresistenz stellt eine universelle Beeinträchtigung des Nutzens von pharmazeutischen Wirkstoffen in vielen klinischen Indikationen dar. Antibakterielle und antifungale Wirkstoffe sind dabei ebenso betroffen wie Wirkstoffe zur Behandlung von Krebs, Virusinfektionen oder durch Parasiten hervorgerufene Erkrankungen. Trotz der unterschiedlichen biologischen Zielstrukturen und Organismen, die bei der Entwicklung von Wirkstoffresistenzen involviert sind, konnten grundlegende molekulare Prozesse identifiziert werden, die zum Verständnis des Auftretens von Resistenzen beitragen und die Bekämpfung dieser nachteiligen Mechanismen erlauben. Strukturelle Informationen über die Prinzipien von Wirkstoffresistenzen sind heute vielfältig vorhanden, sodass neue Wirkstoffe entwickelt werden können, die weniger anfällig gegenüber einer Resistenzbildung sein werden. Dieser wissensbasierte Ansatz ist eine Grundlage für den Kampf gegen das unvermeidbare Auftreten von Wirkstoffresistenzen.
A Modified System for the Synthesis of Enantioenriched N‐Arylamines through Copper‐Catalyzed Hydroamination
Authors: Ichikawa Saki , Zhu Shaolin , Buchwald Stephen L.
Published: May 2018

Despite significant recent progress in copper‐catalyzed enantioselective hydroamination chemistry, the synthesis of chiral N‐arylamines, which are frequently found in natural products and pharmaceuticals, has not been realized. Initial experiments with N‐arylhydroxylamine ester electrophiles were unsuccessful and, instead, their reduction in the presence of copper hydride (CuH) catalysts was observed. Herein, we report key modifications to our previously reported hydroamination methods that lead to broadly applicable conditions for the enantioselective net addition of secondary anilines across the double bond of styrenes, 1,1‐disubstituted olefins, and terminal alkenes. NMR studies suggest that suppression of the undesired reduction pathway is the basis for the dramatic improvements in yield under the reported method.
An Unusual Phase Transition Driven by Vibrational Entropy Changes in a Hybrid Organic–Inorganic Perovskite
Authors: Wei Wenjuan , Li Wei , Butler Keith T. , Feng Guoqiang , Howard Christopher J. , Carpenter Michael A. , Lu Peixiang , Walsh Aron , Cheetham Anthony K.
Published: May 2018

The driving forces for the phase transitions of ABX3 hybrid organic–inorganic perovskites have been limited to the octahedral tilting, order–disorder, and displacement. Now, a complex structural phase transition has been explored in a HOIP, [CH3NH3][Mn(N3)3], based on structural characterizations and ab initio lattice dynamics calculations. This unusual first‐order phase transition between two ordered phases at about 265 K is primarily driven by changes in the collective atomic vibrations of the whole lattice, along with concurrent molecular displacements and an unusual octahedral tilting. A significant entropy difference (4.35 J K−1 mol−1) is observed between the low‐ and high‐temperature structures induced by such atomic vibrations, which plays a main role in driving the transition. This finding offers an alternative pathway for designing new ferroic phase transitions and related physical properties in HOIPs and other hybrid crystals.
Copper‐Catalyzed Borocarbonylative Coupling of Internal Alkynes with Unactivated Alkyl Halides: Modular Synthesis of Tetrasubstituted β‐Borylenones
Authors: Cheng Li‐Jie , Mankad Neal P.
Published: May 2018

Reported is a general procedure to synthesize tetrasubstituted enones, which are borylated in the β‐position, using a copper‐catalyzed four‐component coupling reaction of simple chemical feedstocks: internal alkynes, alkyl halides, bis(pinacolato)diboron (B2pin2), and CO. A broad scope of highly functionalized β‐borylated enones, a largely unknown class of organic compounds, can be accessed efficiently using this method. The synthesis of all‐carbon tetrasubstituted enones was realized by employing the β‐borylated enone unit, without purification, in a Suzuki–Miyaura coupling. The utility of the method was further demonstrated by various transformations, including halogenation, oxidation, and protodeboration, of the corresponding reduced oxaborole species to provide densely substituted allylic alcohol and ketone products.