bluuebunny/crossref_metadata_2025 huggingface dataset:
Comportamento do dióxido de nitrogênio sobre a região nordeste do Brasil e sua relação com variáveis meteorológicas
Authors: Freitas Ismael Guidson Farias , Alves José Carlos da Silva , Mariano Ericka Voss Chagas , Mariano Glauber Lopes
Published: December 2018

The emission of pollutants has become one of the subjects most debated in the last years, due to the increase of fixed emitting sources like industries and movable like the motor vehicles. In the Northeast of Brazil, the high concentrations of pollutants occur mainly in large urban centers, where one of these pollutants is emitted nitrogen dioxide, which is a highly polluting gas. Once observed high concentrations of this pollutant in the atmosphere can cause effects on human health and also influence the formation of acid rain. Thus the objective of this work was to investigate and quantify the total column of nitrogen dioxide gas over the northeastern region of Brazil based on data from the OMI sensor (Ozone Monitoring Instrument) between 2005 and 2015, through statistical techniques for analysis graphic and spatial. Significant variations of the pollutant were identified in the study area, highlighting Salvador, Teresina and Fortaleza, where they showed significant correlation results with meteorological variables. The results showed that Salvador had concentrations of up to 3.5 E+15 (1/m²) in the total NO2 column, while Teresina and Fortaleza had a maximum of 3.0 E+15 (1/m²) and 2,6 E+15 (1/m²), respectively. Therefore, the variations were different in the cities.
Observação direta da turbulência atmosférica na pluma emitida por uma Usina Termoelétrica
Authors: Martins Luís Gustavo Nogueira , Acevedo Otávio Costa , Puhales Franciano Scremin , Oliveira Pablo Eli Soares De , Teichrieb Cláudio Alberto , Silva Samuel , Demarco Giuliano , Costa Felipe Denardin
Published: December 2018

A micrometeorological tower with 11 levels of turbulence observation has been in operation near to the Linhares Geração SA Thermoelectric Plant since August 2016. In particular cases, when the wind blows towards the tower, it is possible to observe directly the physical characteristics of the emitted plume, such as the turbulence and fluxes inside the emitted plume. In the present work, a case is analyzed in which it has occurred. The analysis shows that these events are characterized by an increase in the airwind speed and temperature fluctuations, which starts exactly when the wind direction becomes south, direction which the power plant is located in relation to the tower. Next, it is proved that these events of increase of the fluctuations are in fact turbulent signs, the spectra of the observed time series during the period follow the Law of Kolmogorov. Finally, it is presented the temporal evolutions of the vertical profiles of turbulent kinetic energy and heat turbulent fluxes in the period of the plume passage by the tower.
Sae2/CtIP prevents R-loop accumulation in eukaryotic cells
Authors: Makharashvili Nodar , Arora Sucheta , Yin Yizhi , Fu Qiong , Wen Xuemei , Lee Ji-Hoon , Kao Chung-Hsuan , Leung Justin WC , Miller Kyle M , Paull Tanya T
Published: December 2018

The Sae2/CtIP protein is required for efficient processing of DNA double-strand breaks that initiate homologous recombination in eukaryotic cells. Sae2/CtIP is also important for survival of single-stranded Top1-induced lesions and CtIP is known to associate directly with transcription-associated complexes in mammalian cells. Here we investigate the role of Sae2/CtIP at single-strand lesions in budding yeast and in human cells and find that depletion of Sae2/CtIP promotes the accumulation of stalled RNA polymerase and RNA-DNA hybrids at sites of highly expressed genes. Overexpression of the RNA-DNA helicase Senataxin suppresses DNA damage sensitivity and R-loop accumulation in Sae2/CtIP-deficient cells, and a catalytic mutant of CtIP fails to complement this sensitivity, indicating a role for CtIP nuclease activity in the repair process. Based on this evidence, we propose that R-loop processing by 5’ flap endonucleases is a necessary step in the stabilization and removal of nascent R-loop initiating structures in eukaryotic cells.
Teacher Collegiality in Context of Institutional Logics: A Conceptual Literature Review
Authors: Samuelsson Katarina
Published: December 2018

This article presents an analysis and discussion of the conceptions of teacher collegiality in times of restructuring, where a shift in the governance of teachers’ work from bureaucratic to market principles can be identified. In addition, several actors from different cultural and social worlds want to contribute to education policy and school success, often through collegiality. Through a conceptual research review, a selection of articles on how teacher collegiality is assigned meaning in the context of different institutional logics is analysed. Different kinds of collegiality are presented, all of which have something to contribute to the understanding of teachers’ work; however, they imply different things. Such differences need to be clarified in order to improve the exchange of ideas, cooperation, and mutual understanding between actors in different cultural and social worlds. Researchers, actors, and experts in market-driven societies will thereby have a better chance to exchange ideas and actually understand each other.
Starving at the Laid Table? Journalism, Digitalization and Corporate Capitalism
Authors: Schnell Christiane
Published: December 2018

Professional journalism fulfills an important role in modern democracies, while always standing with one leg in the public sphere and the other in the private media economy. Within the era of digitalization, the limits of a market-driven professionalism become apparent. Since information appears to be easily accessible due to new media, journalism lost its role as a gatekeeper for “what the world needs to know”. But dropping an anachronistic idea of professional authority—as reform projects within the journalistic profession demanded for decades—does not necessarily lead to a more open and participatory public sphere. On the contrary, the chance for reliable news seems to shrink in the everyday flood of information. Facing a severe shortage of professionalism against the background of an oversupply in the field of journalism might indicate a general paradox of contemporary societies.
Profile of anti-retroviral agents use in Colombia
Authors: Machado-Alba Jorge E. , Atehortua-Otero Miguel A. , Cortés-Mejía Diego A.
Published: December 2018

Introducción. La infección por VIH es una pandemia para la que actualmente existe tratamiento farmacológico que puede controlarla y prolongar la expectativa de vida del paciente.Objetivo. Determinar los patrones de prescripción de fármacos antirretrovirales en una población de personas afiliadas al régimen contributivo del Sistema General de Seguridad Social en Salud, Colombia, durante 2015,Materiales y métodos. Estudio de corte transversal, analizando la formulación de pacientes tratados con fármacos antirretrovirales entre el 1 de abril y el 30 septiembre de 2015. Se identificaron variables sociodemográficas, farmacológicas y comorbilidades de los casos. Se hizo análisis mediante SPSS 23.0.Resultados. Se hallaron 641 pacientes con edad media de 39,0±17 años y predominio masculino (60,2%). Los medicamentos más empleados fueron lamivudina-zidovudina (51,6%), lopinavir-ritonavir (36%) y efavirenz (24,5%). La asociación lamivudina-zidovudina más lopinavir-ritonavir fue el esquema más prescrito (29,5%), pero se identificó un total de 80 esquemas diferentes. Ser un adulto entre 45 y 64 años (OR:2,25; IC95%: 1,367-3,713; p=0,001) se asoció con mayor probabilidad de recibir 4 o más antirretrovirales. Un total de 267 (41,6%) pacientes tenían alguna comedicación (rango: 1-18 fármacos); en especial antiulcerosos (57,3%), hipolipemiantes (28,8%) y antihipertensivos (28,5%).Conclusiones. Los pacientes en tratamiento antirretroviral están recibiendo medicamentos de elevado valor intrínseco, a dosis recomendadas, y presentan las mismas comorbilidades asociadas con las condiciones crónicas relacionadas con la edad, pero con gran variedad de esquemas que no se encuentran incluidos en las guías de práctica clínica.
Effects of exercise on the cognition of older women treated with lovastatin
Authors: Molina-Sotomayor Edgardo , Arreguín-Moreno Rocío , Rodríguez Fernando , Pradas Francisco , León Juan Antonio , Gonzalez-Jurado José Antonio
Published: December 2018

Introducción. El deterioro cognitivo tiene una alta incidencia en el adulto mayor.Objetivo. El principal objetivo de este estudio fue analizar los efectos de un programa de caminatas sobre la cognición y la concentración de lípidos en mujeres mayores de 60 años que estaban tratándose con lovastatinaMateriales y métodos. Los participantes fueron distribuidos en dos grupos: grupo ejercicio (EG, n=45) sometido a entrenamiento aeróbico y un grupo inactivo o sedentario (SG, n=22). El estado cognitivo fue evaluado mediante la versión en español del Mini mental test: los niveles de lipoproteínas fueron medidas usando un test de perfil lipídico y la aptitud cardiorrespiratoria es valoró con el Test de marcha de 6 minutos (6MWT)Resultados. EG mostró una mejora significativa (p<0,05) de la aptitud cardiorrespiratoria y en las concentraciones de HDL-Col. Además los resultados en el test de cognición mostraron un tamaño del efecto grande en la orientación espacial, en la atención y en el cálculo. Los decrementos de LDL-Col no fueron significativos (p>0,05)Conclusión. Un programa de entrenamiento progresivo y supervisado para mujeres mayores tratadas con Lovastatina podría inducir una mejora de la actividad cerebral relacionada con HDL-Col, lo cual podría retrasar el deterioro cognitivo.
Puntos de corte provisionales para el diagnóstico de sarcopenia en ancianos de Caldas (Colombia)
Authors: Villada-Gómez Johan Sebastián , González-Correa Clara Helena , Marulanda-Mejía Felipe
Published: December 2018

Introducción. Sarcopenia es la disminución de masa muscular asociado a reducción del rendimiento y función física, siendo predictor de desenlaces adversos en ancianos. Su diagnóstico requiere datos de composición corporal de población joven sana para establecer valores de referencia de baja masa muscular.Objetivo. Establecer puntos de corte provisionales para sarcopenia en ancianos Caldenses a partir de datos de composición muscular esquelética de jóvenes usando bioimpedancia eléctrica.Materiales y métodos. Se utilizaron datos de composición corporal de jóvenes sanos entre 18 y 35 años medidos por bioimpedancia eléctrica. Se derivaron de allí los datos de índice de masa muscular esquelética. Se aplicó la prueba de Kolmogorov Smirnov para evaluar normalidad de los datos y luego se estableció el promedio de índice de masa muscular con sus desviaciones estándar, tanto para hombres como para mujeres.Resultados. A partir de estos datos se estableció como baja masa muscular un índice de masa muscular esquelética 2 desviaciones estándar por debajo de la media del índice de masa muscular en jóvenes, correspondiendo en mujeres a un valor de 6,42 kg/m2 y en hombres de 8,39 kg/m2.Conclusión. Estos valores son similares a los propuestos por algunos autores asiáticos, lo que muestra que la población de esta región tiene características de composición corporal similares a la asiática. Este es el primer estudio que ofrece una descripción de composición corporal muscular esquelética en jóvenes colombianos, y aporta puntos de corte para diagnóstico de sarcopenia en ancianos en región centroandina.
Dopamine and eye movement control in Parkinson’s disease: deficits in corollary discharge signals?
Authors: Railo Henry , Olkoniemi Henri , Eeronheimo Enni , Pääkkönen Oona , Joutsa Juho , Kaasinen Valtteri
Published: December 2018

Movement in Parkinson’s disease (PD) is fragmented, and the patients depend on visual information in their behavior. This suggests that the patients may have deficits in internally monitoring their own movements. Internal monitoring of movements is assumed to rely on corollary discharge signals that enable the brain to predict the sensory consequences of actions. We studied early-stage PD patients (N = 14), and age-matched healthy control participants (N = 14) to examine whether PD patients reveal deficits in updating their sensory representations after eye movements. The participants performed a double-saccade task where, in order to accurately fixate a second target, the participant must correct for the displacement caused by the first saccade. In line with previous reports, the patients had difficulties in fixating the second target when the eye movement was performed without visual guidance. Furthermore, the patients had difficulties in taking into account the error in the first saccade when making a saccade toward the second target, especially when eye movements were made toward the side with dominant motor symptoms. Across PD patients, the impairments in saccadic eye movements correlated with the integrity of the dopaminergic system as measured with [123I]FP-CIT SPECT: Patients with lower striatal (caudate, anterior putamen, and posterior putamen) dopamine transporter binding made larger errors in saccades. This effect was strongest when patients made memory-guided saccades toward the second target. Our results provide tentative evidence that the motor deficits in PD may be partly due to deficits in internal monitoring of movements.
Symmetry breaking of the cellular lobes closely relates to phylogenetic structure within green microalgae of theMicrasteriaslineage (Zygnematophyceae)
Authors: Neustupa Jiri , Stastny Jan
Published: December 2018

Green microalgae of theMicrasteriaslineage are unicellular microorganisms with modular morphology consisting of successively differentiated lobes. Due to their morphological diversity and peculiar morphogenesis, these species are important model systems for studies of cytomorphogenesis and cellular plasticity. Interestingly, the phylogenetic structure of theMicrasteriaslineage and most other Desmidiales is poorly related to the traditional morphological characters used for delimitation of taxa. In this study, we focused on symmetry breaking between adjacent cellular lobes in relation to phylogeny of the studied species. While pronounced morphological asymmetry between the adjacent lobes is typical for some species, others have been characterized by the almost identical morphologies of these structures. We asked whether there is any detectable average shape asymmetry between the pairs of lobes and terminal lobules in 19Micrasteriasspecies representing all major clades of this desmidiacean lineage. Then, we evaluated whether the asymmetric patterns among species are phylogenetically structured. The analyses showed that the phylogeny was in fact strongly related to the patterns of morphological asymmetry between the adjacent cellular lobes. Thus, evolution of the asymmetric development between the adjacent lobes proved to be the key event differentiating cellular shape patterns ofMicrasterias. Conversely, the phylogeny was only weakly related to asymmetry between the pairs of terminal lobules. The subsequent analyses of the phylogenetic morphological integration showed that individual hierarchical levels of cellular morphology were only weakly coordinated with regard to asymmetric variation among species. This finding indicates that evolutionary differentiation of morphogenetic processes leading to symmetry breaking may be relatively independent at different branching levels. Such modularity is probably the key to the evolvability of cellular shapes, leading to the extraordinary morphological diversity of these intriguing microalgae.
Incidence of Thyroid Carcinoma Among Patients With Hyper and Hypothyroidism
Authors: Nayci Ali Emre , Arikan Soykan , Akkus Onder , Segmen Ozgur , Gunver Feray
Published: December 2018

Objective:

Our aim was to determine the incidence of thyroid carcinoma in patients with hyperthyroidism and hypothyroidism and to demonstrate whether hyperthyroidism is actually a protective state against carcinoma.

Background:

In endemic regions for goiter such as Turkey, the rate of cancer is reported to be lower among patients with hyperthyroidism than those with hypothyroidism. However, we observed in our clinic that carcinoma incidence in patients with hyperthyroidism is at least as high as those with hypo-euthyroidism.

Methods:

Cases of bilateral total thyroidectomy performed in the Istanbul Training and Research Hospital General Surgery Clinic between the years 2000 and 2014 were retrospectively examined. Age, gender, hormone levels, and postoperative pathological diagnoses were independently compared.

Results:

Data from 1200 patients was analyzed. Mean age was 49.2. Of the patients 220 (17.5%) were male and 990 (82.5%) were female; 722 of the female patients had benign pathologies and 268 had malignant pathologies, whereas 144 of the male patients had benign and 66 had malignant pathologies. Compared by age, no significant difference was detected in pathological diagnoses and hormone levels. Comparing the pathological diagnoses according to hormone levels, rate of malignancy was significantly higher in patients with hyperthyroidism than those with hypothyroidism or euthyroidism.

Conclusions:

Unlike what is previously accepted, hyperthyroid patients also carry a risk for thyroid carcinoma. Thus, these patients should be followed up for cancer at least as closely as those with hypothyroidism and euthyroidism.
Relationship between classroom plan types and the degree of concentration of the children in elementary schools: A comparative study of open‐plan classrooms and conventional‐plan classrooms
Authors: Ito Keiko , Yokoyama Yurika
Published: December 2018

In this study, the authors collected the data of 229 classrooms in 15 municipal elementary schools in a city, and sorted them into 5 categories according to the degree of openness of the classrooms in the design of borders between classroom and hallway. First, the authors examined the influence of 5 major factors on the degree of concentration of the children during classwork. As a result, the following were found: (1) the degree of concentration of the children is influenced by the classroom plan type and the number and ratio of children in the class who require special supports, and is neither affected by teaching experience of the teacher nor the total number of the children in the class. (2) The general trend of concentration of children in full‐open classrooms does not differ significantly from that in conventional classrooms. However, in the classrooms equipped with movable partition panels for partially separating the classroom from the hallway, it is significantly lower than in the classrooms of other types. The factors of distraction in physical environments were then further analyzed and discussed.
FDA supports medical devices as a viable option for preventing and treating OUD
Authors: Knopf Alison
Published: December 2018

The Food and Drug Administration (FDA) has awarded eight companies “Innovation Challenge” grants to spur the development of medical devices, including diagnostic tests and mobile medical applications, to prevent and treat opioid use disorder (OUD). The FDA launched the challenge last spring, and there were more than 250 applications. “The FDA remains committed to addressing this national crisis on all fronts, with a focus on encouraging medical product innovation to prevent new cases of opioid abuse and addiction and to treat those addicted,” the agency stated in announcing the grants last month.
Ashley pulls lending website after Twitter scuffle
Authors: Knopf Alison
Published: December 2018

Last week, Sarah E. Wakeman, M.D., medical director of the substance use disorders initiative at Massachusetts General Hospital, and assistant professor of medicine at Harvard University, posted a message on Twitter that implied Ashley Addiction Treatment Center, based in Le Havre, Maryland, “says ‘financing available’ including your vehicle as collateral.” She then posted a picture from a lending website, which Ashley had posted a link to on its website.
Telemedicine for SUD: Underused, but will expansion help?
Authors: Knopf Alison
Published: December 2018

Substance use disorder (SUD) treatment by telemedicine — referred to as tele‐SUD — is on the increase, but overall rates of use are still very low compared to the use of telemedicine for mental illness, researchers have found. Reporting in the December issue of Health Affairs, they note that the shortage of SUD treatment providers, especially in rural areas, is contributing to the treatment gap in the United States. However, there are regulatory and reimbursement barriers to tele‐SUD, and federal and state lawmakers are considering ways to reduce these.
Achieving Amorphous Ultralong Room Temperature Phosphorescence by Coassembling Planar Small Organic Molecules with Polyvinyl Alcohol
Authors: Wu Hongwei , Chi Weijie , Chen Zhao , Liu Guofeng , Gu Long , Bindra Anivind Kaur , Yang Guangbao , Liu Xiaogang , Zhao Yanli
Published: December 2018

Development of novel strategies for achieving amorphous ultralong organic phosphorescence (UOP) at room temperature is highly desired. Herein, a simple approach is reported by coassembling small organic molecules with polyvinyl alcohol (PVA) to afford amorphous UOP. These small organic molecules with planar conformation present quenched triplet state emission in an excessive stacking solid state. When coassembling these molecules with PVA, their planar structures are well confined in coassembly films. Such a confined environment leads to restricted molecular rotation and vibration, permitting these molecules to show stable triplet state and generate UOP. In control studies, corresponding structurally distorted molecules are also coassembled with PVA. However, they exhibit very weak or quenched UOP, since distorted structures with molecular rotation and vibration could easily dissipate the excitation energy in dilute film state. By employing this polymer confinement strategy, multicomponent luminescence dyes are further coassembled with PVA for multicolor luminescence displays, providing multicolor, uniform, and flexible luminescence films. This work demonstrates a general strategy of employing small organic molecules to coassemble with PVA to obtain amorphous UOP, which greatly expands the scope of organic molecules for developing simple but useful UOP films.
Self‐Powered MoS2–PDPP3T Heterotransistor‐Based Broadband Photodetectors
Authors: Sun Mengxing , Yang Pengfei , Xie Dan , Sun Yilin , Xu Jianlong , Ren Tianling , Zhang Yanfeng
Published: December 2018

Photodetectors based on monolayer molybdenum disulfide (MoS2) have been demonstrated to exhibit good photodetecting capabilities. However, the relatively large bandgap of monolayer MoS2 has inhibited its application in near‐infrared (NIR) photodetectors. Here, the narrow‐bandgap organic semiconductor poly(diketopyrrolopyrrole‐terthiophene) (PDPP3T) is firstly introduced to the monolayer MoS2 transistor as a NIR light absorbing layer. The MoS2–PDPP3T heterojunction‐based transistor (heterotransistor) shows a broadband photodetecting range from ultraviolet (UV) to NIR region. About one or two orders of magnitude improvement of photoresponsivities have been realized for the MoS2–PDPP3T heterotransistor compared with that of MoS2 transistor. Moreover, due to the formation of MoS2–PDPP3T heterojunction and asymmetric electrodes, the MoS2–PDPP3T heterotransistor shows the self‐powered behavior under zero bias voltage. Flexible MoS2–PDPP3T heterostructure photodetector is also fabricated on the poly(ethylene terephthalate) substrate with reliable performance, which enables a promising photodetection platform for future wearable optoelectronics.
Doping Effect on Conducting Polymer‐Metal Schottky DC Generators
Authors: Shao Hao , Fang Jian , Wang Hongxia , Zhou Hua , Niu Haitao , Chen Fanyan , Yan Guilong , Fu Sida , Cao Yuying , Lin Tong
Published: December 2018

Conducting polymer‐metal Schottky diodes show an interesting mechanical energy‐to‐electricity conversion ability to generate direct current (DC) power without rectification. However, little is reported about how dopants in conducting polymer affect the energy conversion behavior of Schottky diodes. In this study, a novel effect of dopants on mechanical energy‐to‐DC electricity conversion of conducting polymer‐metal Schottky devices is demonstrated. Using polyaniline (PANI) as a model, conducting polymers doped with a series of protonic acids is prepared. Without dopant, the device exhibits low mechanical‐to‐electrical outputs. Protonic acid doping enhances device energy conversion ability, and the dopant molecular dimension plays a significant part in deciding device performance. When HCl is used as dopant, the PANI device could produce peak outputs of 0.9 V and 33.9 µA cm−2 under compressive impact. These novel understandings foster the design of DC generators for various applications.
The ethics of global psychiatric genomics: Multilayered challenges to integrating genomics in global mental health and disability—A position paper of the Oxford Global Initiative in Neuropsychiatric GenEthics (NeuroGenE)
Authors: Kong Camillia , Singh Ilina
Published: December 2018

Psychiatric genomics has the potential to radically improve the prevention and early intervention of serious mental and neurodevelopmental disorders worldwide. However, little work has been done on the ethics of psychiatric genomics—an oversight that could result in poor local uptake, reduced practical/clinical application, and ethical violations in this rapidly developing area of scientific research. As part of the Global Project of the Stanley Center for Psychiatric Research, the Global Initiative in Neuropsychiatric GenEthics (NeuroGenE) based at the University of Oxford aims to embed ethical inquiry within scientific investigation and engage with fundamental ethical questions around a psychiatric genomics approach to mental and neurodevelopmental disorder. This position paper sets out the core aims of the NeuroGenE research programme and explores the importance of a crosscutting research orientation in this field based on multidisciplinary methodologies which can ensure that efforts to translate and apply global psychiatric genomics in public policy and clinical practice are ethically grounded strategies, respectful of different cultures and contexts.
The array of clinical phenotypes of males with mutations in Methyl‐CpG binding protein 2
Authors: Neul Jeffrey L. , Benke Timothy A. , Marsh Eric D. , Skinner Steven A. , Merritt Jonathan , Lieberman David N. , Standridge Shannon , Feyma Timothy , Heydemann Peter , Peters Sarika , Ryther Robin , Jones Mary , Suter Bernhard , Kaufmann Walter E. , Glaze Daniel G. , Percy Alan K.
Published: December 2018

Mutations in the X‐linked gene MECP2 are associated with a severe neurodevelopmental disorder, Rett syndrome (RTT), primarily in girls. It had been suspected that mutations in Methyl‐CpG‐binding protein 2 (MECP2) led to embryonic lethality in males, however such males have been reported. To enhance understanding of the phenotypic spectrum present in these individuals, we identified 30 males with MECP2 mutations in the RTT Natural History Study databases. A wide phenotypic spectrum was observed, ranging from severe neonatal encephalopathy to cognitive impairment. Two males with a somatic mutation in MECP2 had classic RTT. Of the remaining 28 subjects, 16 had RTT‐causing MECP2 mutations, 9 with mutations that are not seen in females with RTT but are likely pathogenic, and 3 with uncertain variants. Two subjects with RTT‐causing mutations were previously diagnosed as having atypical RTT; however, careful review of the clinical history determined that an additional 12/28 subjects met criteria for atypical RTT, but with more severe clinical presentation and course, and less distinctive RTT features, than females with RTT, leading to the designation of a new diagnostic entity, male RTT encephalopathy. Increased awareness of the clinical spectrum and widespread comprehensive genomic testing in boys with neurodevelopmental problems will lead to improved identification.
High‐Yield and Damage‐free Exfoliation of Layered Graphdiyne in Aqueous Phase
Authors: Yan Hailong , Yu Ping , Han Guangchao , Zhang Qinghua , Gu Lin , Yi Yuanping , Liu Huibiao , Li Yuliang , Mao Lanqun
Published: December 2018

The two‐dimensional carbon material graphdiyne (GDY) holds great promise as a semiconductor and porous material, however, exfoliation of bulk GDY into single‐ or few‐layered GDY in the aqueous phase remains a challenge. We report an efficient method for the damage‐free exfoliation of bulk GDY into single‐ or few‐layered GDY with high yield in an aqueous solution of inorganic salts (e.g., Li2SiF6). This was confirmed by spherical‐aberration‐corrected scanning transmission electron microscopy, scanning/transmission electron microscopy, atomic force microscopy, Fourier transform infrared/Raman spectroscopy, X‐ray photoelectron spectroscopy. The method gives high exfoliation efficiency (75 wt %) without creating additional structural defects or oxides in the exfoliated GDY. Theoretical calculations suggest that non‐covalent adsorption of the anion, diffusion of the cation, and subsequent repulsive forces between adjacent flakes are the main driving force for the efficient exfoliation.
Round‐the‐Clock Photocatalytic Hydrogen Production with High Efficiency by a Long‐Afterglow Material
Authors: Cui Guanwei , Yang Xiuli , Zhang Yujia , Fan Yaqi , Chen Ping , Cui Hongyu , Liu Yan , Shi Xifeng , Shang Qiaoyan , Tang Bo
Published: December 2018

Long afterglow materials can store and release light energy after illumination. A brick‐like, micrometer‐sized Sr2MgSi2O7:Eu2+,Dy3+ long‐afterglow material is used for hydrogen production by the photocatalytic reforming of methanol under round‐the‐clock conditions for the first time, achieving a solar‐to‐hydrogen (STH) conversion efficiency of 5.18 %. This material is one of the most efficient photocatalysts and provides the possibility of practical use on a large scale. Its remarkable photocatalytic activity is attributed to its unique carrier migration path and large number of lattice defects. These findings expand the application scope of long afterglow materials and provide a new strategy to design efficient photocatalysts by constructing trap levels that can prolong carrier lifetimes.
Achieving Efficient Incorporation of π‐Electrons into Graphitic Carbon Nitride for Markedly Improved Hydrogen Generation
Authors: Li Jing , Wu Dandan , Iocozzia James , Du Haiwei , Liu Xueqin , Yuan Yupeng , Zhou Wei , Li Zhen , Xue Zhaoming , Lin Zhiqun
Published: December 2018

A rapid and highly efficient strategy for introducing C into g‐C3N4 involves copolymerizing π‐electron‐rich barbituric acid with melamine via a facile microwave‐assisted heating, thereby eliminating the issues in conventional electric furnace heating, such as the severe volatilization, owing to the mismatch of the sublimation temperatures of barbituric acid and melamine. The g‐C3N4 catalyst after optimizing the C‐doping content actively generates increased amounts of H2 under visible light exposure with the highest H2 generation rate of 25.0 μmol h−1, which is nearly 20 times above that using g‐C3N4 produced by conventional electric furnace heating of two identical monomers (1.3 μmol h−1). As such, the microwave‐assisted heating strategy may stand out as an extremely simple route to incorporating π‐electrons into g‐C3N4 with markedly improved photocatalytic performance.
A Masked Cuprous Hydride as a Catalyst for Carbonyl Hydrosilylation in Aqueous Solutions
Authors: Ritter Florian , Mukherjee Debabrata , Spaniol Thomas P. , Hoffmann Alexander , Okuda Jun
Published: December 2018

Redox‐unstable cuprous hydridotriphenylborate was isolated as an N‐heterocyclic carbene adduct [(IPr)Cu(HBPh3)] (IPr=1,3‐bis(2,6‐diisopropylphenyl)imidazol‐2‐ylidene) with good thermal stability. Although this compound displays a contact ion‐pair structure, CuIH‐like catalytic activity was envisaged in carbonyl hydrosilylation. Sufficient moisture stability allowed the catalysis in aqueous/organic media. Mechanistic study further showed that a phenyl group on the borate anion is abstracted by [(IPr)Cu]+ to give the cationic organocopper complex [(IPr)2Cu2(μ‐Ph)][BPh4].
Rapid Construction of Structurally Diverse Quinolizidines, Indolizidines, and Their Analogues via Ruthenium‐Catalyzed Asymmetric Cascade Hydrogenation/Reductive Amination
Authors: Chen Ya , He Yan‐Mei , Zhang Shanshan , Miao Tingting , Fan Qing‐Hua
Published: December 2018

A rapid construction of enantioenriched benzo‐fused quinolizidines, indolizidines, and their analogues by ruthenium‐catalyzed asymmetric cascade hydrogenation/reductive amination of quinolinyl‐ and quinoxalinyl‐containing ketones has been developed. This reaction proceeds under mild reaction conditions, affording chiral benzo‐fused aliphatic N‐heterocyclic compounds with structural diversity in good yields (up to 95 %) with excellent diastereoselectivity (up to >20:1 dr) and enantioselectivity (up to >99 % ee). Furthermore, this catalytic protocol is applicable to the formal synthesis of (+)‐gephyrotoxin.
Fe3O4@SiO2‐copper sucrose xanthate as a green nanocatalyst for N‐, O‐ and S‐arylation
Authors: Radfar Iman , Kazemi Miraki Maryam , Esfandiary Naghmeh , Ghandi Leila , Heydari Akbar
Published: December 2018

Formation of C(sp2)–X bonds was carried out using a Fe3O4@SiO2‐copper(I) sucrose xanthate nanoparticle catalyst with the aid of the copper(I) xanthate moiety in the catalyst which was prepared from the reaction between sucrose and carbon disulfide through an alkaline medium via the traditional Zeise approach. Various techniques were employed for the characterization of these novel nanoparticles. Three sorts of heteroatoms, N, O and S, successfully underwent heteroatom arylation to produce secondary or tertiary amines, ethers and thioethers, respectively.
Synthesis, Structures and Various Biological Applications of New Zn(II) Complexes Having Different Coordination Modes Controlled by the Drug Furosemide in Presence of Bioactive Nitrogen Based Ligands
Authors: Raymoni Ghana , Abu Ali Hijazi
Published: December 2018

Novel Zn(II) complexes with the general formula: [Zn(furo)2(L)n], n = 1 or 2, (furo = furosemide = (4‐chloro‐2‐(furan‐2‐ylmethylamino)‐5‐sulfamoylbenzoic acid) were prepared. The complexes [Zn(furo)2(MeOH)2] (1; MeOH = methanol), [Zn(furo)2(2‐ampy)2] (2; 2‐ampy = 2‐aminopyridine), [Zn(furo)2(2‐ammepy)2] (3; 2‐ammepy = 2‐aminomethylpyridine), [Zn(furo)2(H2O)(2,2‐bipy)] (4; 2,2′‐bipy = 2,2′‐bipyridine), [Zn(furo)2(H2O)(4,4′‐bipy)] (5; 4,4′‐bipy = 4,4′‐bipyridine), [Zn(furo)2(1,10‐phen)] (6; 1,10‐phen = 1,10‐phenanthroline), [Zn(furo)2(2,9‐dmp)] (7; 2,9‐dmp = 2,9‐dimethyl‐1,10‐phenanthroline), and [Zn (furo)2(quin)2] (8; quin = quinoline) were synthesized and characterized using different techniques such as IR, UV–Vis, 1H NMR, 13C NMR, LC/MS and others. The crystal structure of complex (4) was determined using single‐crystal X‐ray diffraction.

The anti‐bacterial activity of complexes (1–8) was tested using agar diffusion method against three gram‐positive (Staphylococcus aureus, Bacillus subtilis and Staphylococcus epidermidis) and three gram‐negative bacteria (Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa). The obtained results showed different Inhibition Zone Diameters (IZD) with various anti‐bacterial activities against the selected gram‐positive and gram‐negative bacteria.

In addition, the rate of bis‐(4‐nitrophenyl) phosphate hydrolysis was measured at different temperatures, different pH values and different concentrations. The rates for the eight complexes were in the following order: complex 4 > 2 > 5 > 8 > 7 > 6 > 3 > 1.
Synthesis of propyl aminopyridine modified magnetite nanoparticles for cadmium (II) adsorption in aqueous solutions
Authors: Tajali Rad Fatemeh , Kefayati Hassan , Shariati Shahab
Published: December 2018

In this study, 2‐aminopyridine functionalized magnetite nanoparticles were chemically synthesized and used for removing Cd2+ ions from aqueous solutions. The synthesized nanoparticles were characterized by Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive analysis of X‐rays (EDX), thermogravimetric analysis (TGA) and vibrating sample magnetometer (VSM). The SEM results showed the synthesized magnetite nanoparticles have particle size around 26 nm. The effects of several variables including solution pH and volume, adsorbent mass, ionic strength and contact time on the Cd2+ adsorption were studied in batch experiments and finally the optimum conditions for adsorption were obtained. The kinetic data were investigated by pseudo‐ first‐order, pseudo‐ second‐order, intraparticle diffusion and Elovich kinetic models and data were described reasonably by pseudo‐ second‐order model (R2 = 0.9996) with qe = 2.31 mg g−1. Adsorption data were analyzed using Langmuir, Freundlich and Temkin isotherm models. The results indicated that the data were well fitted to the Freundlich isotherm model (R2 = 0.9907). After study the possible interference effect of foreign ions on Cd2+ removal, the applicability of the proposed nanoparticles for adsorption from real samples confirmed the successfully removal of Cd2+ ions with removal efficiency higher than 92%. The obtained results showed that the synthesized nanoparticles as a reusable adsorbent can act as a good choice for Cd2+ removal with an easy procedure.
Seeing and thinking in pictures: A review of visual information processing
Authors: Adaval Rashmi , Saluja Geetanjali , Jiang Yuwei
Published: December 2018

Constructive and ecological theories of perception raise questions about whether visual perception is inherently data‐driven (bottom‐up) or interpreted in terms of higher‐order cognitions (top‐down). Analogies between these theoretical perspectives and the two visual systems involved in visual perception (the dorsal and ventral stream) suggest that the literature on visual information processing can be organized around two types of processes: object processing and spatial processing. Object processing involves the identification and recognition of stimuli in the environment and is shaped by existing concepts and associations in memory. It is associated with the processing of properties of objects such as color, size, shape, and pictorial details that are considered in this review. Spatial processing involves the perception of location, movement, spatial relations, and transformation of objects and other stimuli. Imagery‐based processes that are used to transform marketing stimuli in order to simulate various possibilities are reviewed in this section along with individual differences in spatial and visual abilities.
Effects of Substituents on Metastable‐State Photoacids: Design, Synthesis, and Evaluation of their Photochemical Properties
Authors: Liu Junning , Tang Wenqi , Sheng Lan , Du Zhen , Zhang Ting , Su Xing , Zhang Sean Xiao‐An
Published: December 2018

Recently, metastable‐state photoacids have been widely used to control proton transfer in numerous chemical and biological processes as well as applications with visible light. Generally, substituents have a great influence on the photochemical properties of molecules, which will further affect their applications. Yet, the effects of substituents on metastable‐state photoacids have not been studied systematically. In this work, 16 metastable‐state photoacid derivatives were designed and synthesized on the basis of substituents having a large range of σ–π electron–donor–acceptor capabilities. The effects of substituents on the color display [or maximum absorption band(s)], solubility, pKa values, dark/photoacidity, photosensitivity, and relaxation kinetic(s) were investigated in detail. This study will be helpful for the targeted design and synthesis of promising photoacids and the application of their photocontrolled proton‐release processes in functional materials/devices.
Predicting Strain Engineering Strategies Using iKS1317: A Genome‐Scale Metabolic Model ofStreptomyces coelicolor
Authors: Kumelj Tjaša , Sulheim Snorre , Wentzel Alexander , Almaas Eivind
Published: December 2018

Streptomyces coelicoloris a model organism for theActinobacteria, a phylum known to produce an extensive range of different bioactive compounds that include antibiotics currently used in the clinic. Biosynthetic gene clusters discovered in genomes of otherActinobacteriacan be transferred to and expressed inS. coelicolor, making it a factory for heterologous production of secondary metabolites. Genome‐scale metabolic reconstructions have successfully been used in several biotechnology applications to facilitate the over‐production of target metabolites. Here, the authors present iKS1317, the most comprehensive and accurate reconstructed genome‐scale metabolic model (GEM) forS. coelicolor. The model reconstruction is based on previous models, publicly available databases, and published literature and includes 1317 genes, 2119 reactions, and 1581 metabolites. It correctly predicts wild‐type growth in 96.5% of the evaluated growth environments and gene knockout predictions in 78.4% when comparing with observed mutant growth phenotypes, with a total accuracy of 83.3%. However, using a minimal nutrient environment for the gene knockout predictions, iKS1317 has an accuracy of 87.1% in predicting mutant growth phenotypes. Furthermore, we used iKS1317 and existing strain design algorithms to suggest robust gene‐knockout strategies to increase the production of acetyl‐CoA. Since acetyl‐CoA is the most important precursor for polyketide antibiotics, the suggested strategies may be implemented in vivo to improve the function ofS. coelicoloras a heterologous expression host.
Engineering Thermostable CYP2D Enzymes for Biocatalysis Using Combinatorial Libraries of Ancestors for Directed Evolution (CLADE)
Authors: Gumulya Yosephine , Huang Weiliang , D'Cunha Stephlina A. , Richards Katelyn E. , Thomson Raine E. S. , Hunter Dominic J. B. , Baek Jong‐Min , Harris Kurt L. , Boden M. , De Voss James J. , Hayes Martin A. , Isin Emre M. , Andersson Shalini , Jurva Ulrik , Gillam Elizabeth M. J.
Published: December 2018

The structure of metabolites of drug candidates must frequently be characterised during drug discovery and development. However, synthesising metabolites with the correct stereoselective modifications can be challenging for chemically complex parent compounds. Biocatalysis using human drug‐metabolising enzymes, such as cytochrome P450 2D6 (CYP2D6) is an alternative to chemical synthesis. However, most natural enzymes are unstable and have poor efficiency, limiting yields in preparative biotransformations. The aim of this study was to develop a library of robust mutant CYP2D enzymes for biocatalysis. The CLADE (combinatorial libraries of ancestors for directed evolution) approach increased the stability of CYP2D mutants obtained by DNA shuffling using three extant CYP2D forms. The resulting mutants showed divergent profiles of activity towards typical CYP2D substrates and included thermostable forms that may be useful for the further evolution of biocatalysts for specific applications.
Alkene Carboarylation through Catalyst‐Free, Visible Light‐Mediated Smiles Rearrangement
Authors: Whalley David M. , Duong Hung A. , Greaney Michael F.
Published: December 2018

A light‐mediated Truce–Smiles arylative rearrangement is described that proceeds in the absence of any photocatalyst. The protocol creates two C−C bonds from simple starting materials, with the installation of an aryl ring and a difluoroacetate moiety across unactivated alkenes. The reaction proceeds via a radical mechanism, utilizing a light‐mediated reduction of ethyl bromodifluoroacetate by N,N,N′,N′‐tetramethylethylenediamine (TMEDA) to set up intermolecular addition to an unactivated alkene, followed by Truce–Smiles rearrangement.
Mo‐Based Oxidizers as Powerful Tools for the Synthesis of Thia‐ and Selenaheterocycles
Authors: Franzmann Peter , Beil Sebastian B. , Schollmeyer Dieter , Waldvogel Siegfried R.
Published: December 2018

A highly efficient synthetic protocol for the synthesis of thia‐ and selenaheterocycles has been developed. By employing a MoCl5‐mediated intramolecular dehydrogenative coupling reaction, a broad variety of structural motifs was isolated in yields up to 94 %. The electrophilic key transformation is tolerated by several labile moieties like halides and tertiary alkyl groups. Due to the use of disulfide or diselenide precursors, a high atom efficiency was achieved.
2‐Fluoro‐1,3‐diamino‐4,6‐dinitrobenzene (ZXC‐7) and 2‐Fluoro‐1,3,5‐triamino‐4,6‐dinitrobenzene (ZXC‐8): Thermally Stable Explosives with Outstanding Properties
Authors: Zhang Zheng , Ma Jinchao , Zhou Qiuju , Hu Wenxiang , Zhang Xingcheng
Published: December 2018

Two novel, thermally stable explosives, 2‐fluoro‐1,3‐diamino‐4,6‐dinitrobenzene (ZXC‐7) and 2‐fluoro‐1,3,5‐triamino‐4,6‐dinitrobenzene (ZXC‐8), are reported. These two compounds can be prepared by means of simple synthetic methods and they show outstanding properties (detonation velocity, detonation pressure, sensitivity toward mechanical stimuli, and temperature of decomposition). Their structures are very similar to that of 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB). They were isolated and characterized by means of mass spectrometry and multinuclear (1H, 13C) NMR spectroscopy. The structure of ZXC‐7 in the crystalline state was determined by low‐temperature single‐crystal X‐ray diffraction. From the calculated standard molar enthalpy of formation (CBS‐4 M) and the densities (which were determined by a gas pycnometer), the Chapman‐Jouguet detonation properties were predicted by using the EXPLO5 V6.01 thermochemical computer code. The sensitivities of ZXC‐7 and ZXC‐8 towards impact and friction were determined.
Improving Quality, Reproducibility, and Usability of FRET‐Based Tension Sensors
Authors: Gates Evan M. , LaCroix Andrew S. , Rothenberg Katheryn E. , Hoffman Brenton D.
Published: December 2018

Mechanobiology, the study of how mechanical forces affect cellular behavior, is an emerging field of study that has garnered broad and significant interest. Researchers are currently seeking to better understand how mechanical signals are transmitted, detected, and integrated at a subcellular level. One tool for addressing these questions is a Förster resonance energy transfer (FRET)‐based tension sensor, which enables the measurement of molecular‐scale forces across proteins based on changes in emitted light. However, the reliability and reproducibility of measurements made with these sensors has not been thoroughly examined. To address these concerns, we developed numerical methods that improve the accuracy of measurements made using sensitized emission‐based imaging. To establish that FRET‐based tension sensors are versatile tools that provide consistent measurements, we used these methods, and demonstrated that a vinculin tension sensor is unperturbed by cell fixation, permeabilization, and immunolabeling. This suggests FRET‐based tension sensors could be coupled with a variety of immuno‐fluorescent labeling techniques. Additionally, as tension sensors are frequently employed in complex biological samples where large experimental repeats may be challenging, we examined how sample size affects the uncertainty of FRET measurements. In total, this work establishes guidelines to improve FRET‐based tension sensor measurements, validate novel implementations of these sensors, and ensure that results are precise and reproducible. © 2018 International Society for Advancement of Cytometry