bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterising spatio-temporal variability in seasonal snow cover at a regional scale from MODIS data: the Clutha Catchment, New Zealand
Authors: Redpath Todd A. N. , Sirguey Pascal , Cullen Nicolas J.
Published: August 2019

Abstract. A 16-year series of daily snow-covered area (SCA) for 2000–2016
is derived from MODIS imagery to produce a regional-scale snow cover
climatology for New Zealand's largest catchment, the Clutha Catchment.
Filling a geographic gap in observations of seasonal snow, this record
provides a basis for understanding spatio-temporal variability in
seasonal snow cover and, combined with climatic data, provides insight
into controls on variability. Seasonal snow cover metrics including daily SCA, mean snow
cover duration (SCD), annual SCD anomaly and
daily snowline elevation (SLE) were derived and assessed for temporal
trends. Modes of spatial variability were characterised, whilst also preserving
temporal signals by applying raster principal component analysis (rPCA) to
maps of annual SCD anomaly. Sensitivity of SCD to temperature and precipitation variability
was assessed in a semi-distributed way for mountain ranges across the catchment.
The influence of anomalous winter air flow, as characterised by HYSPLIT back-trajectories,
on SCD variability was also assessed. On average, SCA peaks in late
June, at around 30 % of the catchment area, with 10 % of the catchment
area sustaining snow cover for > 120 d yr−1. A persistent mid-winter reduction in
SCA, prior to a second peak in August, is attributed to the prevalence of winter
blocking highs in the New Zealand region. In contrast to other regions
globally, no significant decrease in SCD was observed, but substantial spatial
and temporal variability was present. rPCA identified
six distinct modes of spatial variability, characterising 77 % of
the observed variability in SCD. This analysis
of SCD anomalies revealed strong spatio-temporal variability beyond
that associated with topographic controls, which can result in snow
cover conditions being out of phase across the catchment. Furthermore,
it is demonstrated that the sensitivity of SCD to temperature and
precipitation variability varies significantly across the catchment.
While two large-scale climate modes, the SOI and SAM, fail to explain
observed variability, specific spatial modes of SCD are favoured by
anomalous airflow from the NE, E and SE. These findings illustrate
the complexity of atmospheric controls on SCD within the catchment
and support the need to incorporate atmospheric processes that govern
variability of the energy balance, as well as the re-distribution of
snow by wind in order to improve the modelling of future changes in
seasonal snow.
Interações medicamentosas de interesse em odontologia
Authors: Ioris Lisiane Marcelli Dalmédico , Bacchi André Demambre
Published: August 2019

Objetivo: evidenciar a importância do conhecimento farmacológico na odontologia e identificar as principais interações medicamentosas que podem ocorrer nesse âmbito, fornecendo informações para uma prescrição mais segura e eficaz. Revisão de literatura: foi possível observar que as classes mais prescritas na prática odontológica são os anti-inflamatórios não esteroidais (Aines), antibióticos e analgésicos. As interações mais expressivas em relação aos Aines são com anticoagulantes, provocando aumento de risco de sangramento, fármacos anti-hipertensivos, reduzindo a eficácia anti-hipertensiva, e Lítio, aumentando a toxicidade dessa droga; além disso, podem interagir com fármacos como Efavirenz ou Naltrexona, potencializando risco de lesão hepática. Para antibióticos, as interações mais comuns são: com etanol, podendo ocasionar reação tipo dissulfiram; com Etinilestradiol, comprometendo a eficácia contraceptiva; além de interações importantes com anticoagulantes, Isotretinoina e Metotrexato. Opioides associados a benzodiazepínicos ou a outros depressores, como a Amitriptilina, podem resultar em profunda sedação; interações com a Fluoxetina podem diminuir a analgesia. Considerações finais: há significativa possibilidade de interações medicamentosas na odontologia, podendo comprometer a saúde dos pacientes, sendo importante o conhecimento do cirurgião-dentista sobre as possíveis interações e seus potenciais riscos, a fim de evitar complicações durante o tratamento.
Talent Management and its Relationship to Career Stability among Academic Leaders at Al-Hussein Bin Talal University
Authors: Waswas Dima , Jwaifell Mustafa
Published: August 2019

This study aimed to identify the level of applying talent management and achieving career stability among academicleaders at Al-Hussein Bin Talal University (AHU), and to investigate the relation between talent management and itsdomains with career stability. The study population consisted of all the (55) administrative academics in Al-HusseinBin Talal University occupying positions: Dean, Vice Dean, and Head of Department. The analytical approach wasused to develop the study tools and the descriptive approach to determine the level of applying talent managementand the degree of career stability. To achieve the study objectives, two tools were used: applying talent managementand achieving career satisfaction where its validity and reliability calculated. The results showed that means fortalent management ranged between (3.236-3.448) with medium agreement; the highest among them was the domainof (talents acquisition), followed by the domain of (talents development), while the lowest was the talentsmaintenance domain. The total mean was (3.344) with a medium degree of agreement. The results also indicated thatthe means for the items of achieving career stability ranged between (3.218-4.273) with high and medium degrees ofagreement, and the mean for the total was (3.82) with a high degree of agreement.The results showed that correlation coefficients between the talent management and the career stability rangedbetween (0.685-0.799), which indicates that there is a positive relationship between them.
Pelos interiores - a invenção do caipira: cultura, tradição e cozinha
Authors: Ferreira Elton Bruno , Santos de Matos Maria Izilda
Published: August 2019

Inseridos numa perspectiva da história cultural, estes escritos focalizam a polêmica em torno do caipira e da cultura caipira, tendo como foco central a produção de Cornélio Pires (publicações, composições, registros sonoros, espetáculos, ações de divulgação). A cultura caipira é aqui identificada como modo de ser e de viver do homem do campo na área denominada de Paulistânia (ELLIS JUNIOR, 1951; CANDIDO, 2010), que incorpora Vale do Paraíba (Rio de Janeiro e São Paulo), se estendendo pelo oeste do estado de São Paulo (Piracicaba/Tiete/Pirapora), e atingindo o sul de Minas Gerais e Mato Grosso e norte do Paraná. O desafio da análise é discutir a construção cultural do caipira, rastreando suas representações imagéticas, os debates em torno da figura do Jeca, bem como, focalizar gostos, hábitos, práticas e tradições alimentares dos caipiras, privilegiando as décadas iniciais do século XX.Palavras-chave: Cultura Popular. Pires, Cornélio, 1884-1958. Culinária Brasileira.
Nedd4 E3 ligase and beta-arrestins regulate ubiquitination, trafficking, and stability of the mGlu7 receptor
Authors: Lee Sanghyeon , Park Sunha , Lee Hyojin , Han Seulki , Song Jae-man , Han Dohyun , Suh Young Ho
Published: August 2019

The metabotropic glutamate receptor 7 (mGlu7) is a class C G protein-coupled receptor that modulates excitatory neurotransmitter release at the presynaptic active zone. Although post-translational modification of cellular proteins with ubiquitin is a key molecular mechanism governing protein degradation and function, mGlu7 ubiquitination and its functional consequences have not been elucidated yet. Here, we report that Nedd4 ubiquitin E3 ligase and β-arrestins regulate ubiquitination of mGlu7 in heterologous cells and rat neurons. Upon agonist stimulation, β-arrestins recruit Nedd4 to mGlu7 and facilitate Nedd4-mediated ubiquitination of mGlu7. Nedd4 and β-arrestins regulate constitutive and agonist-induced endocytosis of mGlu7 and are required for mGlu7-dependent MAPK signaling in neurons. In addition, Nedd4-mediated ubiquitination results in the degradation of mGlu7 by both the ubiquitin-proteasome system and the lysosomal degradation pathway. These findings provide a model in which Nedd4 and β-arrestin act together as a complex to regulate mGlu7 surface expression and function at presynaptic terminals.
A geometric attractor mechanism for self-organization of entorhinal grid modules
Authors: Kang Louis , Balasubramanian Vijay
Published: August 2019

Grid cells in the medial entorhinal cortex (MEC) respond when an animal occupies a periodic lattice of ‘grid fields’ in the environment. The grids are organized in modules with spatial periods, or scales, clustered around discrete values separated on average by ratios in the range 1.4–1.7. We propose a mechanism that produces this modular structure through dynamical self-organization in the MEC. In attractor network models of grid formation, the grid scale of a single module is set by the distance of recurrent inhibition between neurons. We show that the MEC forms a hierarchy of discrete modules if a smooth increase in inhibition distance along its dorso-ventral axis is accompanied by excitatory interactions along this axis. Moreover, constant scale ratios between successive modules arise through geometric relationships between triangular grids and have values that fall within the observed range. We discuss how interactions required by our model might be tested experimentally.
Spatiotemporal patterns of urban thermal environment and comfort across 180 cities in summer under China’s rapid urbanization
Authors: Ren Zhibin , Fu Yao , Du Yunxia , Zhao Hongbo
Published: August 2019

Background

China is considered as the largest and most rapidly urbanizing nation in the world. However, possible changes of urban thermal environment and comfort under the rapid urbanization in China still remain poorly understood at a national scale.

Methods

Based on the data collected from 180 cities in 1990, 2005, and 2015 in China, the spatiotemporal patterns of urban thermal environment and comfort in summer and their relationships with urbanization variables were investigated in this study.

Results

Our results indicate that urban thermal environment has changed greatly during the 25 years. Furthermore, the changes of urban climate in different regions are inconsistent. The Physiological Equivalent Temperature (PET) at most cities (81%) in China increased from 1990 to 2015, which suggested that urban thermal comfort in China was also deteriorating during the 25 years. However, while the PET of some cities in China began to decrease from 2005 to 2015, there were still 33% of cities that had positive trends,which mainly located in North region. Urbanization resulted in a significant influence on urban climate. Compared to southern cities, northern cities were more sensitive to urbanization impact. The most important contribution to increasing of PET for urbanization variables is gross domestic product, followed by urban population. The analysis results reveal changing patterns of urban thermal comfort in China during summer season. It can help urban government and managers improve urban thermal environment and comfort.
Age-associated changes of cytochrome P450 and related phase-2 gene/proteins in livers of rats
Authors: Xu Shang-Fu , Hu An-Ling , Xie Lu , Liu Jia-Jia , Wu Qin , Liu Jie
Published: August 2019

Cytochrome P450s (CYPs) are phase-I metabolic enzymes playing important roles in drug metabolism, dietary chemicals and endogenous molecules. Age is a key factor influencing P450s expression. Thus, age-related changes of CYP 1–4 families and bile acid homeostasis-related CYPs, the corresponding nuclear receptors and a few phase-II genes were examined. Livers from male Sprague-Dawley rats at fetus (−2 d), neonates (1, 7, and 14 d), weanling (21 d), puberty (28 and 35 d), adulthood (60 and 180 d), and aging (540 and 800 d) were collected and subjected to qPCR analysis. Liver proteins from 14, 28, 60, 180, 540 and 800 days of age were also extracted for selected protein analysis by western blot. In general, there were three patterns of their expression: Some of the drug-metabolizing enzymes and related nuclear receptors were low in fetal and neonatal stage, increased with liver maturation and decreased quickly at aging (AhR, Cyp1a1, Cyp2b1, Cyp2b2, Cyp3a1, Cyp3a2, Ugt1a2); the majority of P450s (Cyp1a2, Cyp2c6, Cyp2c11, Cyp2d2, Cyp2e1, CAR, PXR, FXR, Cyp7a1, Cyp7b1. Cyp8b1, Cyp27a1, Ugt1a1, Sult1a1, Sult1a2) maintained relatively high levels throughout the adulthood, and decreased at 800 days of age; and some had an early peak between 7 and 14 days (CAR, PXR, PPARα, Cyp4a1, Ugt1a2). The protein expression of CYP1A2, CYP2B1, CYP2E1, CYP3A1, CYP4A1, and CYP7A1 corresponded the trend of mRNA changes. In summary, this study characterized three expression patterns of 16 CYPs, five nuclear receptors, and four phase-II genes during development and aging in rat liver, adding to our understanding of age-related CYP expression changes and age-related disorders.
Contribution of Home Gardening to Household Dietary Intake among Peri-urban Households of Imo State, Nigeria
Authors: Uzoamaka N. Akwiwu, , Chinwe N. Obichere,
Published: August 2019

Rapid urbanization, industralization, land grabbing and dwindling land resources is fast eroding the practice of home gardening in peri-urban areas. This has altered the dietary intake pattern of peri-urban households who hitherto could augment their meals from products of gardens around their homes. The study assessed home gardening contribution to dietary intake among households in peri-urban areas of Imo State. Specifically, the study sought to ascertain the types of home gardening practiced, the contribution of home garden to the household dietary intake and identify the constraints of peri-urban households in practicing home gardening. Multistage sampling procedure was adopted in the selection of sample. Okigwe, Orlu and Owerri-West Local Government Areas (LGAs) were purposively selected from each of the agricultural zones in Imo State for their peri-urban nature. Four communities were purposively selected from the three LGAs were home gardening was mostly practiced. A survey was conducted to find out households which practiced home gardening. Ten households each were then randomly selected from these communities, making a total of one hundred and twenty (120) respondents for the study. Data collected were analysed using descriptive statistics (mean, frequency and percentage). The result showed that majority (54.2%) of the respondents practiced mixed crop home gardening while 43.3% practiced mixed farm home gardening. The level of contribution of home gardening to dietary intake among households was (53.3%). A fairly high number (47.5%) of peri-urban households expressed experiencing high constraints to practicing home gardening. It is recommended that peri-urban households should be educated on other methods of  home gardening where land is in limited supply to improve household dietary intake.
The Potential and Challenges of Using ICT as a Vehicle for Rural Communication as Characterised by Smallholder Farmers
Authors: Dlamini Mbuyazwe M. , Worth Steven
Published: August 2019

Agricultural extension is a communication network linking different stakeholders in agriculture to improve their productivity and Information Communication Technology (ICT) has been utilised as an extension tool for enhancing information flow between agricultural extension services and their clients. The application of ICT in agricultural extension and rural development has significantly increased in several countries where it has provided an adequate access to agricultural information. Efforts are, therefore, needed to scale up investments in physical ICT infrastructure and services across developing country. This could be realised through the implementation of interventions aimed at speeding up assimilation and adoption of improved agricultural technology and management practices of the less productive smallholder farmers. Drawing on relevant published works, this paper argues that agricultural knowledge and information management within an extension system can improve productivity of smallholder farmers. The role of ICTs in agricultural extension is discussed together with its challenges towards the improvement of productivity among smallholder farmers. Smallholder farmers need to develop and utilize ICT based knowledge management techniques to implement strategies and interventions to transform the agricultural sector and improve their productivity. Agricultural extension is the ideal mechanism that can facilitate the introduction and subsequent adoption of ICTs for effective knowledge and information management.
Factors of Performance of Secondary Schools in Science, Mathematics and English
Authors: Cabrella Jem Boy B. , Junsay Marilou D.
Published: August 2019

This sequential exploratory mixed methods research aimed to describe which among the demographics, school profile, teacher factor, student factor, learning resources and classroom management, management and governance, family background and parental involvement significantly influenced and predicted the performance of the secondary schools in Science, Mathematics and English in Davao del Sur Division and thereafter to develop empirical models. The instrument used was developed through the responses of the KII informants, concepts of Creswell, and factor analyses. Using complete enumeration, the researcher selected 68 teachers and principals as respondents. Findings revealed that educational attainment, school based management, field of specialization significantly predicted competition; school type, teachers’ attitude and motivation, class size were linked with NAT results in Science; school type, length of service, teachers’ attitude and motivation, principal’s projects and programs, and school size were associated with NAT results in Mathematics; school type, teachers’ attitude and motivation, and classroom management positively correlated with NAT results in English; and school type, teacher’s attitude and motivation, family background and parental involvement, and length of service significantly linked with NAT results in Science, Mathematics and English. The empirical models adopted were: (1) YCompetition = -5.028 + 2.472*Educational Attainment + 1.514*School Based Management – 1.531*Field of Specialization, (2) YNATScience = 7.814 – 32.872*School Type + 13.007*Teacher’s Attitude and Motivation + 14.318*Class Size, (3) YNATMathematics = 74.026 – 28.828*School Type + 5.381* Length of Service + 9.523* Teacher’s Attitude and Motivation – 6.782* Principal’s Projects and Programs – 4.935* School Size, (4) YNATEnglish = 52.674 – 18.505* School Type + 11.362* Teacher’s Attitude and Motivation – 6.518* Classroom Management, and (5) YNATAverage = 60.645 – 26.052*School Type + 8.362* Teacher’s Attitude and Motivation – 4.902* Family Background and Parental Involvement + 4.158* Length of Service.
Evaluation of Staphylococcal Activity of Garcinia kola Almonds
Authors: Karamoko Ouattara , Didier Dibi Koffi Saint , Monon Kone , Abou Ouattara , Issa Bagre
Published: August 2019

The emergence of infectious diseases, particularly staphylococcal infections, treatment failures and the more high cost of treatment of infections caused by resistant staphylococci called to find other care alternatives. This study was initiated to evaluate the antibacterial activity of the aqueous extract from Garcinia kola almonds on the in vitro growth of Staphylococcus aureus strains. The methods of diffusion in agar and liquid media were used for susceptibility testing and MIC and MBC determination. The tests were performed on four strains of S. aureus and one reference strain. The minimum inhibitory concentrations of the extracts ranged from 3.12 mg/mL and 12.5 mg/mL and the minimum bactericidal concentrations between 6.25 mg/mL and 25 mg/mL. The lowest value of MIC and MBC was observed with S. aureus ATCC 29213 while the greatest value of these same parameters was obtained on S. aureus 993C/18 and S. aureus 1075C/18. The aqueous almonds extract of Garcinia kola had a bactericidal activity on all the strains of S. aureus studied. This could justify the use of Garcinia kola almonds in the treatment of various diseases in traditional society.
Geostatistics
Authors: Zimmerman Dale L.
Published: August 2019

Geostatistics is an application of the theory of random functions to spatially indexed data. The methods, initially proposed by Matheron in mining and petroleum exploration, found their way into mainstream statistics in the 1980s. Topics in geostatistical methodology considered here are classical univariate geostatistics, multivariate geostatistics, nonstationary geostatistics, geostatistics on non‐Euclidean (including space–time) domains, and geostatistical simulation.
Computational Statistics for Cybersecurity
Authors: Marchette David J.
Published: August 2019

This article discusses several applications of computational statistics for cybersecurity. Nonparametric probability density estimation is widely used in computational statistics, and has many applications in cybersecurity, both for understanding and analyzing data and for classification and anomaly detection. These methods are described and applied to network flows and malware characterization. Streaming data methods are discussed and illustrated on the network flows data. Methods for analyzing graphs and time series of graphs are discussed and illustrated.
Circulating IGFBP‐2: a novel biomarker for incident dementia
Authors: McGrath Emer R. , Himali Jayandra J. , Levy Daniel , Conner Sarah C. , DeCarli Charles S. , Pase Matthew P. , Courchesne Paul , Satizabal Claudia L. , Vasan Ramachandran S. , Beiser Alexa S. , Seshadri Sudha
Published: August 2019

Objective

To determine the association between plasma insulin‐like growth factor binding protein 2 (IGFBP‐2) and cognitive outcomes.

Methods

We measured plasma IGFBP‐2 levels in 1596 (53% women, mean age 68.7 [SD 5.7] years) dementia‐free Framingham Offspring cohort participants between 1998 and 2001. Multivariable Cox proportional hazards models related plasma IGFBP‐2 to subsequent risk of incident dementia and Alzheimer’s disease. MRI brain measures and cognitive performance were included as secondary outcomes.

Results

During a median follow‐up of 11.8 (Q1, Q3: 7.1, 13.3) years, 131 participants developed incident dementia, of whom 98 were diagnosed with Alzheimer’s disease. The highest tertile of IGFBP‐2, compared to the lowest tertile, was associated with an increased risk of incident all‐cause dementia (hazard ratio [HR] 2.89, 95% CI 1.63–5.13) and Alzheimer’s disease (HR 3.63, 95% CI 1.76–7.50) in multivariable analysis. Higher circulating IGFBP2 levels were also cross‐sectionally associated with poorer performance on tests of abstract reasoning but not with MRI‐based outcomes. After adding plasma IGFBP‐2 levels to a conventional dementia prediction model, 32% of individuals with dementia were correctly assigned a higher predicted risk, while 8% of individuals without dementia were correctly assigned a lower predicted risk (overall net reclassification improvement index, 0.40, 95% CI 0.22–0.59).

Interpretation

Elevated circulating IGFBP‐2 levels were associated with an increased risk of both all‐cause dementia and Alzheimer’s disease. Addition of IGFBP2 plasma levels to a model of traditional risk factors significantly improved dementia risk classification. Manipulation of insulin‐like growth factor signaling via IGFBP‐2 may be a promising therapeutic target for dementia.
Mediation of Adverse Pregnancy Outcomes in Autoimmune Conditions by Pregnancy Complications: A Mediation Analysis of Autoimmune Conditions and Adverse Pregnancy Outcomes
Authors: Bandoli Gretchen , Singh Namrata , Strouse Jennifer , Baer Rebecca J. , Donovan Brittney M. , Feuer Sky K. , Nidey Nichole , Ryckman Kelli K. , Jelliffe‐Pawlowski Laura L. , Chambers Christina D.
Published: August 2019

Objective

Autoimmune conditions are associated with an increased risk of adverse pregnancy complications and outcomes, suggesting that pregnancy complications may mediate the excess risk. We performed a causal mediation analysis to quantify the mediated effects of autoimmune conditions on adverse pregnancy outcomes.

Methods

We queried a California birth cohort created from linked birth certificates and hospital discharge summaries. From 2,963,888 births, we identified women with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), psoriasis, and inflammatory bowel disease (IBD). Pregnancy complications included preeclampsia/hypertension, gestational diabetes mellitus, and infection in pregnancy. Adverse pregnancy outcomes were preterm birth, cesarean delivery, and small for gestational age. We performed a mediation analysis to estimate the total effects of each autoimmune condition and adverse pregnancy outcome and the indirect effects through pregnancy complications.

Results

All 4 autoimmune conditions were associated with preterm birth and cesarean delivery, and RA, SLE, and IBD were associated with offspring that were small for gestational age. The strongest mediator of RA, SLE, and psoriasis was preeclampsia/hypertension, accounting for 20–33% of the excess risk of preterm births and 10–19% of excess cesarean deliveries. Gestational diabetes mellitus and infections generally mediated <10% of excess adverse pregnancy outcomes. Of the 4 autoimmune conditions, selected pregnancy complications mediated the least number of adverse pregnancy outcomes among women with IBD.

Conclusion

We found evidence that some excess risk of adverse pregnancy outcomes is mediated through pregnancy complications, particularly preeclampsia/hypertension. Quantifying excess risk and associated pathways provides insight into the underlying etiologies of adverse pregnancy outcomes and can inform intervention strategies.
“I Don’t Have to Think About Watching the Ground”: A Qualitative Study Exploring the Concept of Vigilance as an Important Outcome for Ankle Reconstruction
Authors: Pinsker Ellie B. , Sale Joanna E. M. , Gignac Monique A. M. , Daniels Timothy R. , Beaton Dorcas E.
Published: August 2019

Objective

To understand patients’ experiences of ankle reconstruction for treatment of end‐stage ankle osteoarthritis.

Methods

Individuals were recruited from a cohort of individuals who had undergone total ankle replacement or ankle fusion. English‐speaking individuals who had surgery at least 1 year prior were invited to participate. Semistructured, face‐to‐face interviews relying on a phenomenological approach were conducted in a private hospital clinic room.

Results

A total of 25 adults (12 women, 13 men), ages 25–82 years, were interviewed for 1–2 hours. Participants commonly described a state of having to keep careful watch for potential environmental challenges. Vigilance was related to ongoing symptoms (i.e., pain, stiffness) and concerns regarding balance, stability, and potential damage to the fused ankle or implant. Vigilance was described along a continuum, with higher levels associated with stress and mental exhaustion. Vigilance affected participants’ perception of their surgical outcome, with high vigilance levels linked to negative perceptions of outcome. The degree to which individuals perceived the need for vigilance was influenced by environmental factors like uneven ground or crowds. Contrary to descriptions of vigilance in the coping literature, vigilance related to ankle reconstruction constituted a situational, rather than dispositional, response.

Conclusion

Vigilance and its associated burden are not captured by current instruments. The mental load and worry associated with vigilance was important to patients, distinct from related pain or functional status. Thus, reducing high levels of vigilance appears to be an appropriate target for patient‐centered treatment outcomes. A thorough battery of outcome measures for ankle reconstruction should consider this domain.
Laser‐Generated Nanocrystals in Perovskite: Universal Embedding of Ligand‐Free and Sub‐10 nm Nanocrystals in Solution‐Processed Metal Halide Perovskite Films for Effectively Modulated Optoelectronic Performance
Authors: Guo Pengfei , Yang Xiaokun , Ye Qian , Zhang Jin , Wang Hongyue , Yu Huiwu , Zhao Wenhao , Liu Chen , Yang He , Wang Hongqiang
Published: August 2019

Regulating the chemical/physical features of solution processed metal halide perovskite films by integrating sub‐10 nm nanocrystals is a highly promising strategy to advance their outstanding optoelectronic performance. However, significant challenges remain for the universal embedding of the well‐defined nanocrystals in the film matrix. By generating nanocrystals in desired solvents via pulsed laser irradiation in liquid, the authors demonstrate the effective decoration of sub‐10 nm nanocrystals in perovskite films for enhanced optoelectronic performance. It is believed that this improved performance is due to the modification of the widely adopted “antisolvent” to a novel “anti‐colloidal‐solution” (ACS). Exemplified by a typical ACS; carbon dots in chlorobenzene, its encouraging superiority in regulating, not only the films morphology, but also the electronic structure, is demonstrated. This results in perovskite solar cells with a champion efficiency of 21.41% as well as a pronounced stability over 5000 h in relative humidity of 40%. The capability of nanocrystal embedding for boosted photovoltaic performance is further exploited by employing other laser generated ACSs. Such a strategy may open up a route to regulating hybrid perovskite film performance via nanocrystal embedding for photovoltaics or even beyond optoelectronic applications.
Optimal heating profiles in tubular reactors with solid‐phase axial wall conduction for isothermal operation
Authors: Venkateswaran Sunjeev , Wilhite Benjamin , Kravaris Costas
Published: August 2019

Optimal heat input profiles to maintain near isothermal operation in endothermic tubular reactors with axial solid‐phase conduction were derived using a one‐dimensional steady state plug flow model capturing the main transport phenomena in flow reactors. A cost criterion to minimize the deviation from isothermality was defined and optimal control theory is applied to calculate the optimal heating profiles as a function of position. It is shown the perfect isothermality is mathematically possible only if the wall conduction term is infinitesimally small. Using singular optimal control theory, analytical expressions of the input profiles are derived including a simple criterion for near‐isothermal operation in terms of dimensionless reactor parameters.
Male infant with paternal uniparental diploidy mosaicism and a 46,XX/46,XY karyotype
Authors: Spier Isabel , Engels Hartmut , Stutte Sonja , Reutter Heiko , Bartels Enrika , Matos Meder Sarah , Begemann Matthias , Mangold Elisabeth , Eggermann Thomas
Published: August 2019

A male patient with mosaic paternal uniparental diploidy (PUD) is presented. After birth, the patient presented with hypoglycemia, hemihypertrophy, umbilical hernia, and hepatomegaly. Afterward pancreatic hypertrophy, liver hemangiomas, and cysts were detected sonographically. At the age of 3.5 months, hepatoblastoma was diagnosed. To investigate suspected Beckwith‐Wiedemann syndrome (BWS), extensive genetic analyses were performed using DNA from chorionic villus sampling, amniocentesis, and peripheral blood lymphocytes (chromosome analysis, methylation‐specific multiplex ligation‐dependent probe amplification assays, microsatellite analyses, and single nucleotide polymorphism array analysis). These analyses led to the detection of mosaic PUD. In peripheral blood lymphocytes, a male cell line (46,XY[27]/46,XX[5]) predominated, suggesting a mixture of uniparental isodisomy and heterodisomy. The genetic analyses suggest that the mosaic PUD status was attributable to fertilization of an oocyte by two sperms, with subsequent triploidy rescue giving rise to haploidy, which in turn was rescued. Notably, in the majority of the 28 mosaic PUD patients reported to date, BWS was initially suspected. Mosaic PUD status is associated with a higher risk for a broad range of malignant and benign tumors than in BWS. As tumors can also occur after childhood surveillance into adolescence is indicated. Mosaic PUD must therefore be considered in patients with suspected BWS.
Early life maternal sociality predicts juvenile sociality in blue monkeys
Authors: Thompson Nicole A. , Cords Marina
Published: August 2019

Maternal effects are widespread in living organisms though little is known about whether they shape individual affiliative social behavior in primates. Further, it remains a question whether maternal effects on affiliative behavior differ by offspring sex, as they do in other physiological systems, especially in species with high levels of adult sexual dimorphism and divergence in social niches. We explored how direct and indirect experiences of maternal affiliative behavior during infancy predicted affiliative behavior approximately 1–6 years later during the juvenile period, using behavioral data from 41 wild blue monkey juveniles and their 29 mothers, and controlling for individual age, sex, and maternal rank. Female juveniles spent less time grooming with any partner and with peers the more maternal grooming they received during infancy, whereas males groomed more with any partner and with peers. Similarly, the more that mothers groomed with other adult females during subjects’ infancy, female subjects played less with peers, and male subjects played more as juveniles. Further, this maternal effect on social behavior appears specific to early life, as the same aspects of mothers’ sociality measured throughout subjects’ development did not predict juvenile behavior. Overall, our results suggest that both direct and indirect experience of mother's affiliative behavior during infancy influence an individual's affiliation later in life that sexes respond differently to the maternal affiliation, and that the first year of life is a critical window.
Bioinspirierte Nicht‐Häm‐Eisenoxidationskatalyse: Beteiligung von Oxoeisen(V)‐Oxidantien an der Spaltung starker C‐H‐Bindungen
Authors: Kal Subhasree , Xu Shuangning , Que Lawrence
Published: August 2019

Nicht‐Häm‐Eisenenzyme generieren leistungsstarke und vielfältige Oxidantien, die eine Vielzahl an Oxidationsreaktionen vermitteln, einschließlich der Funktionalisierung von inerten C‐H‐Bindungen, die eine anspruchsvolle Aufgabe für Chemiker darstellt. Die oxidativen Fähigkeiten dieser Enzyme inspirieren Bioorganiker zur Entwicklung synthetischer Modelle, um die Fähigkeit solcher Enzyme zur Vermittlung schwierigster Oxidationsreaktionen nachzuahmen und die Mechanismen derartiger Transformationen zu erforschen. Eisen‐Sauerstoff‐Intermediate wie Eisen(III)‐Hydroperoxo‐Spezies und hochvalente Eisen‐Sauerstoff‐Spezies wurden bei Untersuchungen dieser bioinspirierten katalytischen Systemen abgefangen und identifiziert, wobei Letztgenannte als aktives Oxidationsmittel für die meisten dieser Systeme vorgeschlagen wurden. In diesem Aufsatz heben wir die jüngsten spektroskopischen und mechanistischen Fortschritte hervor, die Licht auf die verschiedenen Wege geworfen haben, die von bioinspirierten Nicht‐Häm‐Eisensystemen zur Bildung der hochvalenten Eisen‐Sauerstoff‐Zwischenprodukte genutzt werden können.
Novel bifunctional lanthanide‐centered nanophosphors for latent fingerprint detection and anti‐counterfeiting applications
Authors: Saif M. , Fouad R.
Published: August 2019

Production of hybrid organic/inorganic complexes such as lanthanide phosphors in the nanodomain for human fingerprint visualization and anti‐counterfeiting ink under biocompatible UVA and blue light has not yet been studied that thoroughly. This paper presents the preparation of novel, bifunctional, green and red nanophosphors based on Eu3+ and Tb3+ complexes with quinolinone ligand (H2L). They have been prepared and characterized for latent fingerprint detection and anti‐counterfeiting ink applications. The analytical data confirm that the ligand acts in a monoanionic bidentate manner through OO donor sites, forming mononuclear complexes, formulated as [Ln(HL)3(C2H5OH)3] (Ln = Eu3+ or Tb3+; L = 1‐ethyl‐4‐hydroxy‐3‐(nitroacetyl)quinolin‐2‐(1H)‐one). The Eu3+ and Tb3+ complexes have nanospherical morphologies with average particle sizes of 17 and 5 nm, respectively. Pure red and green photoluminescence with long lifetime values has been obtained from the Eu3+ and Tb3+ complexes, respectively, under non‐harmful UVA and blue illumination. Latent fingerprint details, including their characteristic three levels, have been clearly identified from various forensic (non‐porous, semi‐porous, highly fluorescent porous) substrates using red (Eu3+) and green (Tb3+) nanophosphors. The green nanophosphor powder has a greater capability for visualizing latent fingerprints from highly fluorescent porous surfaces as compared to the red one. Both nanophosphor complexes have been used to develop luminescent ink for anti‐counterfeiting applications.
Silicotungstic acid modified Ce‐Fe‐Ox catalyst for selective catalytic reduction of NOx with NH3: Effect of the amount of HSiW
Authors: Song Zhongxian , Xing Yun , Zhang Xuejun , Zhao Heng , Zhao Min , Zhao Jinggang , Ma Zi'ang , Zhang Qiulin
Published: August 2019

The HSiW(x)/Ce‐Fe catalysts were used to research the effect of silicotungstic acid contents on the catalytic activity in the selective catalytic reduction of NOx with NH3. Doping different contents of silicotungstic acid affected surface species and redox property as well as the catalytic activity. With the increasing amount of HSiW (x = 5%, 10% and 20%), the redox reaction between Fe3+/Fe2+ and Ce4+/Ce3+ enhanced, which could improve the ratio of Ce3+ and Fe3+. And then, more Ce3+ increased the ratio of chemisorbed oxygen (Oα). Besides, the type and strength of acid sites over HSiW(x)/Ce‐Fe was affected by the HSiW contents. These factors facilitated the catalytic performance. Thus, the NOx conversion of HSiW(x)/Ce‐Fe(x = 20%) was higher than 90%, which maintained in a wide temperature range between 200 and 400 °C.
Investigating the catalytic activity of a novel phase‐boundary catalyst in oxidation of styrene
Authors: Yaghoubidoust Fatemeh , Salimi Esmaeil , A. Ati Ali , Nur Hadi
Published: August 2019

Inhibiting the environment pollutions motivated the development of green catalytic systems. The present research proposed a novel model of phase‐boundary catalyst by using octadecyltrichlorosilane/polypyrrole/reduced graphene oxide/cotton (OTS/PPy/RGO/CT) for the oxidation of styrene by aqueous hydrogen peroxide. The catalytic activities were examined in both stirring and static conditions. The effect of electric current was also studied in static condition. The structural properties of the fabricated catalysts were characterized by X‐ray diffractometer, Fourier transformed infrared spectroscopy, field emission scanning electron microscopy, and thermal analysis. Moreover, the influence of PPy and RGO on electrical current of textile was also examined by using four‐point probe technique. The catalytic activity of OTS/RGO/CT showed that the RGO could act as the catalytic active site in the oxidation of styrene with aqueous hydrogen peroxide, as indicated by the 21% enhancement in the conversion of styrene when the RGO amount was increased (12 times) in OTS/RGO/CT in stirring condition. Finally, it could be stated that RGO‐loaded cotton textile was a promising heterogonous catalyst for the oxidation reaction, specifically for the oxidation of styrene with aqueous hydrogen peroxide.
Near‐visible stereolithography of a low shrinkage cationic/free‐radical photopolymer blend and its nanocomposite
Authors: Invernizzi Marta , Suriano Raffaella , Muscatello Allegra , Turri Stefano , Levi Marinella
Published: August 2019

In this work, a newly prepared cationic/free‐radical photopolymer, which consists of two epoxies and a tetrafunctional acrylate, is presented for the first time for a visible light stereolithography (SL), showing the advantages of both cationic and free‐radical resins. An onium salt, commonly used as a cationic UV initiator, and a photosensitizer make the blend suitable for a near‐visible (405 nm) SL. An increase in the polymerization rate and a drop in the induction period are observed for the newly prepared cationic/free‐radical blend, compared with either only cationic systems or free‐radical resins. This suggests that the combination of cationic and free‐radical polymerizations in a single resin has a positive synergistic effect. The addition of silica nanoparticles to the blend provides a reinforcing and toughening effect. Indeed, the resin loaded with silica shows a 31% increase in the elastic modulus, compared with the unfilled resin. Regarding the values of tensile strength and elongation at break, they, respectively, grow by 47 and 15%, when the nanocomposite resin is compared with the neat resin. A very low volumetric shrinkage of 0.7% and a remarkable printing quality of objects obtained with this new photopolymer will enable the 3D printing of microrobots, bioengineering microdevices, and sensors. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48333.
Porous carbon nanosheet with high surface area derived from waste poly(ethylene terephthalate) for supercapacitor applications
Authors: Wen Yanliang , Kierzek Krzysztof , Min Jiakang , Chen Xuecheng , Gong Jiang , Niu Ran , Wen Xin , Azadmanjiri Jalal , Mijowska Ewa , Tang Tao
Published: August 2019

Converting waste plastics into valuable carbon materials has obtained increasing attention. In addition, carbon materials have shown to be the ideal electrode materials for double‐layer supercapacitors owing to their large specific surface area, high electrical conductivity, and stable physicochemical properties. Herein, an easily operated approach is established to efficiently convert waste poly(ethylene terephthalate) beverage bottles into porous carbon nanosheet (PCNS) through the combined processes of catalytic carbonization and KOH activation. PCNS features an ultrahigh specific surface area (2236 m2 g−1), hierarchically porous architecture, and a large pore volume (3.0 cm3 g−1). Such excellent physicochemical properties conjointly contribute to the outstanding supercapacitive performance: 169 F g−1 (6 M KOH) and 135 F g−1 (1 M Na2SO4). Furthermore, PCNS shows a high capacitance of 121 F g−1 and a corresponding energy density of 30.6 Wh kg−1 at 0.2 A g−1 in the electrolyte of 1 M TEATFB/PC. When the current density increases to 10 A g−1, the capacitance remains at 95 F g−1, indicating the extraordinary rate capability. This work not only proposes a facile approach to synthesize PCNS for supercapacitors, but also puts forward a potential sustainable way to recycle waste plastics and further hopefully mitigates the waste plastics‐related environmental issues. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48338.
Deformation and failure of polycarbonate in an electric field
Authors: Zhang Ci , Li Zhenpeng , Zhu Lei , Olah Andrew , Baer Eric
Published: August 2019

Electrically induced mechanical stress was produced on a monolithic polycarbonate (PC) film when subjected to an instantaneous direct current voltage using a needle‐plane electrode setup. Three different experimental methods were used to investigate the electrically induced mechanical deformation on the glassy PC film, namely, morphological observation, energy loss analysis, and dielectric hysteresis study. It was found that the PC film exhibited elastic behavior at the nominal electric field below 200 MV m−1, showing no indentation on the film surface. When the nominal field was above 200 MV m−1, a spherical indentation was created. The depth and diameter of the deformation increased in response to the applied electric field. Subsequent thermal annealing of the deformed film revealed a recoverable “delayed elastic” and an unrecoverable “plastic” deformation. A three‐stage electrically induced mechanical deformation mechanism was proposed based on the experimental results, including a correlation between the energy loss and the deformed volume. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48341.
One‐Pot Cascade Transformation of Glucal into Structurally Diverse Drug‐Like Scaffolds
Authors: Yao Hui , Willam Ronny , Wang Siming , He Jingxi , Guo Tai , Liu Xue‐Wei
Published: August 2019

A diversity‐oriented synthesis strategy to produce three types of structurally drug‐like N‐heterocyclic‐fused rings has been developed from abundant biomass‐derived d‐glucal, aniline and water in a stereoselective manner. The overall transformation which entails a cascade of Ferrier reaction and 4π conrotatory imino‐Nazarov cyclization was performed in one‐pot allowing convenient preparation of scaffolds of high molecular complexity from relatively simple starting materials. While indoline‐fused products were readily accessible using ortho‐unsubstituted secondary anilines as substrates, reactions with ortho‐hydroxyl‐anilines furnished fused 1,4‐benzoxazines instead. In both cases, InBr3 acted as the Lewis acid catalyst. By altering InBr3 to Ln(OTf)3, the indoline‐fused products could be further converted into tetrahydroquinoline‐fused cyclopentenones via ensuing retro‐ene rearrangement.