bluuebunny/crossref_metadata_2025 huggingface dataset:
Manipulating the Optical Properties of Carbon Dots by Fine‐Tuning their Structural Features
Authors: Luo Hui , Papaioannou Nikolaos , Salvadori Enrico , Roessler Maxie M. , Ploenes Gereon , van Eck Ernst R. H. , Tanase Liviu C. , Feng Jingyu , Sun Yiwei , Yang Yan , Danaie Mohsen , Belen Jorge Ana , Sapelkin Andrei , Durrant James , Dimitrov Stoichko D. , Titirici Maria‐Magdalena
Published: August 2019

As a new class of sustainable carbon material, “carbon dots” is an umbrella term covering many types of materials. Herein, a broad range of techniques was used to develop the understanding of hydrothermally synthesized carbon dots, and it is shown how fine‐tuning the structural features by simple reduction/oxidation reactions can drastically affect their excited‐state properties. Structural and spectroscopic studies found that photoluminescence originates from direct excitation of localized fluorophores involving oxygen functional groups, whereas excitation at graphene‐like features leads to ultrafast phonon‐assisted relaxation and largely quenches the fluorescent quantum yields. This is arguably the first study to identify the dynamics of photoluminescence including Stokes shift and allow the relaxation pathways in these carbon dots to be fully resolved. This comprehensive investigation sheds light on how understanding the excited‐state relaxation processes in different carbon structures is crucial for tuning the optical properties for any potential commercial applications.
Exploring Chinese EFL teachers' knowledge and beliefs relating to the teaching of English reading in public primary schools in China
Authors: Luo Meina , Main Susan , Lock Graeme , Joshi R. Malatesha , Zhong Chenyin
Published: August 2019

The present study explored knowledge and beliefs about reading instruction of Chinese teachers teaching English as a foreign language (EFL). Theoretical Orientation to Reading Profile and the Survey of Basic Language Constructs Related to Literacy Acquisition were administered to 262 EFL teachers in the south‐eastern part of China. Additionally, three teachers were interviewed, and their instructional practices were observed. The results showed that there was no correlation between teachers' self‐efficacy beliefs and the performance on the knowledge of basic language construct survey. However, it was found that teachers' knowledge, beliefs, and instructional practices were mediated by the Chinese EFL contextual factors. Educational and practical implications are discussed.
Rapid automatized naming in a developmental perspective between ages 4 and 10
Authors: Åvall Malena , Wolff Ulrika , Gustafsson Jan‐Eric
Published: August 2019

During the last decades, rapid automatized naming (RAN) has been widely examined as a predictor of reading ability, but very few studies have examined the development of RAN itself. The present study followed children from ages 4 until 10, focusing on RAN performance in a developmental perspective. Relations within and between alphanumeric and nonalphanumeric RAN were investigated both concurrently and over time. The result shows that individual differences in RAN objects are stable between ages 4 and 10, with the most rapid growth of mean performance between ages 4 and 6. Early performance on RAN objects predicts both performance on RAN digits and RAN letters at age 8 and the further development between ages 8 and 10. Further, low‐performing children at age 4 develop their performance on RAN digits and RAN letters later compared with high‐performing children, and RAN digits performance reaches a plateau earlier than RAN letters performance.
Linking properties of an orb‐weaving spider's capture thread glycoprotein adhesive and flagelliform fiber components to prey retention time
Authors: Opell Brent D. , Burba Cassandra M. , Deva Pritesh D. , Kin Matthew H. Y. , Rivas Malik X. , Elmore Hannah Mae , Hendricks Mary L.
Published: August 2019

An orb web's adhesive capture spiral is responsible for prey retention. This thread is formed of regularly spaced glue droplets supported by two flagelliform axial lines. Each glue droplet features a glycoprotein adhesive core covered by a hygroscopic aqueous layer, which also covers axial lines between the droplets, making the entire thread responsive to environmental humidity.

We characterized the effect of relative humidity (RH) on ability of Argiope aurantia and Argiope trifasciata thread arrays to retain houseflies and characterize the effect of humidity on their droplet properties. Using these data and those of Araneus marmoreus from a previous study, we then develop a regression model that correlated glycoprotein and flagelliform fiber properties with prey retention time. The model selection process included newly determined, humidity‐specific Young's modulus and toughness values for the three species' glycoproteins.

Argiope aurantia droplets are more hygroscopic than A. trifasciata droplets, causing the glycoprotein within A. aurantia droplets to become oversaturated at RH greater than 55% RH and their extension to decrease, whereas A. trifasciata droplet performance increases to 72% RH. This difference is reflected in species' prey retention times, with that of A. aurantia peaking at 55% RH and that of A. trifasciata at 72% RH.

Fly retention time was explained by a regression model of five variables: glue droplet distribution, flagelliform fiber work of extension, glycoprotein volume, glycoprotein thickness, and glycoprotein Young's modulus.

The material properties of both glycoprotein and flagelliform fibers appear to be phylogenetically constrained, whereas natural selection can more freely act on the amount of each material invested in a thread and on components of the thread's aqueous layer. Thus, it becomes easier to understand how natural selection can tune the performance of viscous capture threads by directing small changes in these components.
Litter addition decreases plant diversity by suppressing seeding in a semiarid grassland, Northern China
Authors: Zhang Ang , Wang Dong , Wan Shiqiang
Published: August 2019

Plant community diversity is conducive to maintain the regional ecosystems stability and ecosystem services. Seed germination is one of the main ways to regulate plant diversity, owing to seedling recruitment as a basis for plant community renewal. However, the exact mechanism of how plant litter affects seedling recruitment, and species richness is not yet fully understood. Therefore, a litter addition and removal experiment was established in a semiarid grassland to study the effects of plant litter on seedling recruitment and species richness from April to August in 2016 and 2017 in Northern China. The positive correlation between species richness and seedling recruitment indicated that a guarantee of seedling recruitment was the main precondition to protect species richness. Adding rather than removing litter significantly reduced species richness. Litter addition inhibited species richness by directly increasing mechanical damage or indirectly reducing photosynthetically active radiation and seedling recruitment. The results of this study are conducive to understand the evolutionary and regulatory mechanisms of community species richness and seedling recruitment in grassland ecosystems after adding or removing plant litter.

OPEN RESEARCH BADGES

This article has been awarded Open Data, Open Materials and Preregistered research design Badges. All materials and data are publicly accessible via the Open Science Framework at https://doi.org/10.5061/dryad.5dj3jg5 and http://doi.org/10.5061/dryad.13gj03s
Old divergence and restricted gene flow between torrent duck (Merganetta armata) subspecies in the Central and Southern Andes
Authors: Alza Luis , Lavretsky Philip , Peters Jeffrey L. , Cerón Gerardo , Smith Matthew , Kopuchian Cecilia , Astie Andrea , McCracken Kevin G.
Published: August 2019

Aim

To investigate the structure and rate of gene flow among populations of habitat‐specialized species to understand the ecological and evolutionary processes underpinning their population dynamics and historical demography, including speciation and extinction.

Location

Peruvian and Argentine Andes.

Taxon

Two subspecies of torrent duck (Merganetta armata).

Methods

We sampled 156 individuals in Peru (M. a. leucogenis; Chillón River, n = 57 and Pachachaca River, n = 49) and Argentina (M. a. armata; Arroyo Grande River, n = 33 and Malargüe River, n = 17), and sequenced the mitochondrial DNA (mtDNA) control region to conduct coarse and fine‐scale demographic analyses of population structure. Additionally, to test for differences between subspecies, and across genetic markers with distinct inheritance patterns, a subset of individuals (Peru, n = 10 and Argentina, n = 9) was subjected to partial genome resequencing, obtaining 4,027 autosomal and 189 Z‐linked double‐digest restriction‐associated DNA sequences.

Results

Haplotype and nucleotide diversities were higher in Peru than Argentina across all markers. Peruvian and Argentine subspecies showed concordant species‐level differences (ΦST mtDNA = 0.82; ΦST autosomal = 0.30; ΦST Z chromosome = 0.45), including no shared mtDNA haplotypes. Demographic parameters estimated for mtDNA using IM and IMa2 analyses, and for autosomal markers using ∂a∂i (isolation‐with‐migration model), supported an old divergence (mtDNA = 600,000 years before present (ybp), 95% HPD range = 1.2 Mya to 200,000 ybp; and autosomal ∂a∂i = 782,490 ybp), between the two subspecies, characteristic of deeply diverged lineages. The populations were well‐differentiated in Argentina but moderately differentiated in Peru, with low unidirectional gene flow in each country.

Main conclusions

We suggest that the South American Arid Diagonal was preexisting and remains a current phylogeographic barrier between the ranges of the two torrent duck subspecies, and the adult territoriality and breeding site fidelity to the rivers define their population structure.
Divergence in drought‐response traits between sympatric species of Mimulus
Authors: Mantel Samuel J. , Sweigart Andrea L.
Published: August 2019

Differential adaptation to local environmental conditions is thought to be an important driver of speciation. Plants, whose sedentary lifestyle necessitates fine‐tuned adaptation to edaphic conditions such as water availability, are often distributed based on these conditions. Populations occupying water‐limited habitats may employ a variety of strategies, involving numerous phenotypes, to prevent and withstand desiccation. In sympatry, two closely related Mimulus species—M. guttatus and M. nasutus—occupy distinct microhabitats that differ in seasonal water availability. In a common garden experiment, we characterized natural variation within and between sympatric M. guttatus and M. nasutus in the ability to successfully set seed under well‐watered and drought conditions. We also measured key phenotypes for drought adaptation, including developmental timing, plant size, flower size, and stomatal density. Consistent with their microhabitat associations in nature, M. nasutus set seed much more successfully than M. guttatus under water‐limited conditions. This divergence in reproductive output under drought was due to differences in mortality after the onset of flowering, with M. nasutus surviving at a much higher rate than M. guttatus. Higher seed set in M. nasutus was mediated, at least in part, by a plastic increase in the rate of late‐stage development (i.e., fruit maturation), consistent with the ability of this species to inhabit more ephemeral habitats in the field. Our results suggest adaptation to water availability may be an important factor in species maintenance of these Mimulus taxa in sympatry.
Effects of extreme drought and wet events for tree mortality: Insights from tree‐ring width and carbon isotope ratio in a Siberian larch forest
Authors: Tei Shunsuke , Sugimoto Atsuko , Yonenobu Hitoshi , Kotani Ayumi , Maximov Trofim C.
Published: August 2019

Recent studies suggest that forest vulnerability to tree mortality has increased as a result of extreme climate events such as severe drought and heavy rain. However, little is known about the mortality processes, particularly when they are induced by heavy rain. A dendroecological analysis was conducted on living and dead trees in a Siberian larch forest using the chronologies of 30 years of radial growth and carbon isotope (Δ13C) discrimination. The analysis demonstrates the relationship between heavy rain and larch tree mortality. Radial growth and Δ13C patterns in dead trees at a wet subsite diverged from those of living trees only during the heavy rain period in 2005–2007. On the other hand, the radial growth and Δ13C patterns in dead trees at the dry subsite diverged from those of living trees after severe drought events in 1998 and in 2002–2003. At the wet subsite, the heavy rain was intense enough to push the larch trees past their mortality threshold, whereas previous drought conditions also contributed to tree mortality at the dry subsite. Our results demonstrated that the process of larch tree mortality differs with site‐specific topographical soil moisture conditions, even when synchronous tree death occurs in a specific year of climatic extremes.
Improved root turnover assessment using field scanning rhizotrons with branch order analysis
Authors: Huo Changfu , Cheng Weixin
Published: August 2019

Root turnover is a key process contributing to soil carbon storage, nutrient cycling, and other ecosystem functions. However, quantifying root turnover rates remains highly uncertain and methodologically challenging. Field rhizotrons were employed to quantify root turnover times using median longevities of five branching orders in a Larix gmelinii plantation. Root images were recorded by scanning the rhizotron windows at a monthly interval during four growing seasons. Root demographic data and branching orders were obtained by analyzing these images using Rootfly software coupled with manual mouse‐tracing of individual roots. Root longevities and turnover estimates were calculated using these data. Roots of different branching orders showed significantly different turnover times. The mean turnover times of the first‐order roots and second‐order roots were 284 and 994 d, respectively. Roots of higher branching orders (third to fifth orders) remained alive at the end of the 4‐yr experimental period, indicating much longer turnover times than the duration of the experiment. Root turnover times increased exponentially with branching orders. Further analysis of these data suggested that root branching orders combined with sampling biases, timing of root cohorts, and longevity distribution patterns crucially influenced root turnover times. The method of combining field glass rhizotrons with electronic scanning permits quantification of root turnover for five branching orders in a temperate forest. The overall result empirically demonstrates the crucial role of branching orders for accurately quantifying root turnover times.
Accounting for aboveground carbon storage in shrubland and woodland ecosystems in the Great Basin
Authors: Fusco Emily J. , Rau Benjamin M. , Falkowski Michael , Filippelli Steven , Bradley Bethany A.
Published: August 2019

Improving the accuracy of carbon accounting in terrestrial ecosystems is critical for understanding carbon fluxes associated with land cover change, with significant implications for global carbon cycling and climate change. Semi‐arid ecosystems account for an estimated 45% of global terrestrial ecosystem area and are in many locations experiencing high degrees of degradation. However, aboveground carbon accounting has largely focused on tropical and forested ecosystems, while drylands have been relatively neglected. Here, we used a combination of field estimates, remotely sensed data, and existing land cover maps to create a spatially explicit estimate of aboveground carbon storage within the Great Basin, a semi‐arid region of the western United States encompassing 643,500 km2 of shrubland and woodland vegetation. We classified the region into seven distinct land cover categories: pinyon‐juniper woodland, sagebrush steppe, salt desert shrub, low sagebrush, forest, non‐forest, and other/excluded, each with an associated carbon estimate. Aboveground carbon estimates for pinyon‐juniper woodland were continuous values based on tree canopy cover. Carbon estimates for other land cover categories were based on a mean value for the land cover type. The Great Basin ecosystems contain an estimated 295.4 Tg in aboveground carbon, which is almost double the previous estimates that only accounted for forested ecosystems in the same area. Aboveground carbon was disproportionately stored in pinyon‐juniper woodland (43.7% carbon, 16.9% land area), while the shrubland systems accounted for roughly half of the total land area (49.1%) and one‐third of the total carbon. Our results emphasize the importance of distinguishing and accounting for the distinctive contributions of shrubland and woodland ecosystems when creating carbon storage estimates for dryland regions.
Evaluation of cytotoxicity and genotoxicity induced by oleic acid‐coated iron oxide nanoparticles in human astrocytes
Authors: Fernández‐Bertólez Natalia , Costa Carla , Brandão Fátima , Duarte José Alberto , Teixeira Joao Paulo , Pásaro Eduardo , Valdiglesias Vanessa , Laffon Blanca
Published: August 2019

Iron oxide nanoparticles (ION) are gaining importance as diagnostic and therapeutic tool of central nervous system diseases. Although oleic acid‐coated ION (O‐ION) have been described as stable and biocompatible, their potential neurotoxicity was scarcely evaluated in human nervous cells so far. The primary aim of this work was to assess the molecular and cellular effects of O‐ION on human astrocytes (A172 cells) under different experimental conditions. An extensive set of cyto‐ and genotoxicity tests was carried out, including lactate dehydrogenase release assay, cell cycle alterations, and cell death production, as well as comet assay, γH2AX assay, and micronucleus (MN) test, considering also iron ion release capacity and alterations in DNA repair ability. Results showed a moderate cytotoxicity related to cell cycle arrest and cell death promotion, regardless of serum presence. O‐ION induced genotoxic effects, namely primary DNA damage, as detected by the comet assay and H2AX phosphorylation, but A172 cells were able to repair this particular damage because no chromosome alterations were found (confirmed by MN test results). Accordingly, no effects on the DNA repair ability were observed. The presence of serum proteins did not influence O‐ION toxicity. Iron ions released from the O‐ION surface seemed not to be responsible for the cytotoxic and genotoxic effects observed. Environ. Mol. Mutagen. 2019. © 2019 Wiley Periodicals, Inc.
Enhanced lipid production by Rhodotorula glutinis CGMCC 2.703 using a two‐stage pH regulation strategy with acetate as the substrate
Authors: Zhang Wen , Wu Jing , Zhou Yu‐Jie , Liu Hong‐Juan , Zhang Jian‐An
Published: August 2019

In recent years, VFAs as a novel, inexpensive substrate for biodiesel production have become a hot research topic. The effect of pH on lipid production by Rhodotorula glutinis when using acetate as a substrate was studied. The optimized initial acetate concentration and C/N ratio were 23 g/L and 350, respectively. In 1‐L bioreactors containing an initial acetate concentration of 23 g/L, the most suitable pH for cell growth was 6.6, while pH 7.0 was found optimal for lipid production. In the pH‐stat fed‐batch fermentation, an increased biomass yield of 67.2 g/L was obtained at pH 6.6, while an increased lipid titer of 29.3 g/L was obtained at pH 7.0. When using a two‐stage pH regulation culture strategy, the biomass yield, lipid titer, and lipid content reached 68.2 g/L, 35.8 g/L, and 52.5%, respectively. Both the biomass yield and lipid production were obviously enhanced. Compared with the batch culture, the biomass yield, lipid titer, and lipid content were increased 15.6‐fold, 19.1‐fold, and 21.0%, respectively, by using the two‐stage pH regulation culture strategy. The composition of the main fatty acids was compared when acetate or glucose was used as the substrate. The composition of the lipids produced using both substrates was similar to that of palm oil, indicating that lipids produced by R. glutinis in the presence of acetate showed promise for use as a biodiesel feedstock.
Porcine placental extract facilitates memory and learning in aged mice
Authors: Yamauchi Akihiro , Tone Takahiro , Sugimoto Koji , Seok Lim Hong , Kaku Taiichi , Tohda Chihiro , Shindo Takayuki , Tamada Koji , Mizukami Yoichi , Hirano Eiichi
Published: August 2019

Aging induces a decline in both memory and learning ability without predisposing an individual to diseases of the central nervous system, such as dementia. This decline can have a variety of adverse effects on daily life, and it can also gradually affect the individual and the people they are surrounded by. Since recent evidence indicated that placental extract has effects on brain function such as memory, we hypothesized that placental extract could ameliorate the age‐associated reduction in cognitive function in aging. Here, we investigated the effect of new modified porcine placental extract (SD‐F) on memory ability in aged mice at both the behavioral and molecular levels. Our results revealed that SD‐F significantly enhanced memory ability in the object recognition and object location tasks in a dose‐dependent manner in aged mice relative to controls. The numbers of Nissl‐positive cells in the hippocampal cornu ammonis 3 (CA3) and dentate gyrus (DG) regions were increased in SD‐F‐treated aged mice relative to controls. RNA‐seq analysis of the hippocampus of aged mice identified 542 differentially expressed genes, of which 216 were up‐regulated and 326 were down‐regulated in SD‐F‐treated mice relative to controls. Of the 216 up‐regulated genes, we identified four characteristic genes directly related to memory, including early growth response protein 1 (Egr1), growth arrest and DNA‐damage‐inducible, beta (Gadd45b), NGFI‐A binding protein 2 (Nab2), and vascular endothelial growth factor a (Vegfa). These results suggest that the efficacy of SD‐F involves upregulation of these genes.
Headquarters‐subsidiary knowledge strategies at the cluster level
Authors: Li Pengfei , Bathelt Harald
Published: August 2019

Research Summary

This article examines how multinational enterprises (MNEs) leverage knowledge across clusters. Based on the geographical sources and the contextuality of knowledge, we construct a typology of four MNE knowledge strategies across space: replicating, scouting, connecting, and integrating, and take into consideration their spatial, industrial, and leadership contexts. A fuzzy‐set qualitative comparative analysis of 49 pairs of headquarters‐subsidiary linkages between Canada and China suggests that replicating strategies occur in cluster‐to‐non‐cluster contexts or in fields with a knowledge gap between the two countries, whereas scouting strategies are typical in non‐cluster‐to‐cluster investments. Connecting and integrating strategies are focused on cluster‐to‐cluster contexts. We also find that while connecting occurs in fields where knowledge is locally bounded, integrating takes place in nonlocally bounded contexts. Finally, scouting and integrating strategies are associated with home nationals as subsidiary leaders.

Managerial Summary

How do multinational enterprises (MNEs) transfer knowledge over space between clusters and between other locations? To explore this question, we construct a typology of four MNE knowledge strategies (replicating, scouting, connecting, and integrating) and examine the spatial, industrial, and leadership conditions of each. By examining 49 headquarter‐subsidiary linkages between Canada and China through detailed interviews, we find that replicating strategies occur in cluster‐to‐non‐cluster contexts or industries with a knowledge gap between the two countries, whereas scouting strategies are typical in non‐cluster‐to‐cluster investments. Connecting and integrating strategies are focused on cluster‐to‐cluster contexts. We also find that while connecting occurs in fields where knowledge is locally bounded, integrating dominates where this is not the case. Finally, scouting and integrating strategies are associated with home nationals as subsidiary leaders.
Serious immune‐related adverse events in patients with head and neck cancer after checkpoint blockade: Systematic review
Authors: Shah Mohsin , Jomaa Mona K. , Ferrarotto Renata , Yeung Sai‐Ching J. , Hanna Ehab Y. , Reyes‐Gibby Cielito C.
Published: August 2019

Background

Immune checkpoint inhibitors confer significant clinical benefit by bolstering immune‐system activity, however, they also produce a spectrum of immune‐related adverse events (irAEs). Rapid recognition and timely treatment of these patients is essential for improved outcomes.

Methods

We conducted a systematic review of English‐language articles in MEDLINE, EMBASE, Web of Science, PubMed, and Cochrane CENTRAL databases on patients with head and neck cancer treated with immune checkpoint inhibitors who developed treatment‐related adverse events.

Results

Of 1715 unique citations, 11 studies met inclusion criteria. Eight patients with serious irAEs were reported from case reports and case series. Overall, 46 treatment‐related AEs were identified from the pooled 791 patients with at least 12 having potential relevance to irAEs. The most frequent AEs observed in patients receiving PD‐1 inhibitors involved the endocrine, cutaneous, and gastrointestinal systems.

Conclusions

Characterizing irAEs in longitudinal studies is needed for developing strategies for their prompt recognition and management.
Retro‐Corey‐Chaykovsky Epoxidation: Converting Geminal Disubstituted Epoxides to Ketones
Authors: Li Siqi , Li Pingfan , Xu Jiaxi
Published: August 2019

Corey‐Chaykovsky epoxidation has been widely applied in the conversion of aldehydes and ketones to epoxides with sulfonium and sulfoxonium ylides. The reverse transformation is realized for conversion of geminal disubstituted epoxides to ketones in the presence of DABCO in refluxing mesitylene. The method is a weak basic transformation from epoxides to ketones with loss of a methylene group and can be applied as an alternative strategy of the acid‐catalyzed Meinwald rearrangement or oxidation for conversion of epoxides to carbonyl compounds.
Maternal depression and infant attachment security: A meta‐analysis
Authors: Barnes Jennifer , Theule Jennifer
Published: August 2019

The purpose of this study is to clarify the magnitude of the association between maternal depression and infant attachment nonsecurity, and to identify possible moderators of this relationship. An extensive literature search was conducted using multiple databases of both published and unpublished studies. A meta‐analysis was conducted to determine the relationship between maternal depression and infant attachment security and to establish the effect size. The main findings from this meta‐analysis, which included 42 studies, indicate that there is a small, yet significant, relationship between maternal depression and infant attachment nonsecurity. The rate of nonsecurity in infants of mothers with depression was approximately 20% higher than expected rates in a nonclinical population, and the association between depressive symptoms and nonsecurity was small, but significant. Infants of mothers with depression were nearly twice as likely to have a nonsecure attachment than were infants of healthy mothers. Depression measure and maternal sample source were identified as significant moderators of the odds ratio effect size. Results of this study demonstrate that there is a significant relationship between maternal depression and infant attachment nonsecurity, and suggest that interventions that focus on both maternal mental health and the attachment relationship are warranted.
A machine perspective of atomic defects in scanning transmission electron microscopy
Authors: Dan Jiadong , Zhao Xiaoxu , Pennycook Stephen J.
Published: August 2019

Enabled by the advances in aberration‐corrected scanning transmission electron microscopy (STEM), atomic‐resolution real space imaging of materials has allowed a direct structure‐property investigation. Traditional ways of quantitative data analysis suffer from low yield and poor accuracy. New ideas in the field of computer vision and machine learning have provided more momentum to harness the wealth of big data and sophisticated information in STEM data analytics, which has transformed STEM from a localized characterization technique to a macroscopic tool with intelligence. In this review article, we discuss the prime significance of defect topology and density in two‐dimensional (2D) materials, which have proved to be a powerful means to tune a wide range of properties. Subsequently, we systematically review advanced data analysis methods that have demonstrated promising prospects in analyzing STEM data, particularly for identifying structural defects, with high throughput and veracity. A unified framework for atomic structure identification is also summarized.
Chemoresistive materials for electronic nose: Progress, perspectives, and challenges
Authors: Park Seo Yun , Kim Yeonhoo , Kim Taehoon , Eom Tae Hoon , Kim Soo Young , Jang Ho Won
Published: August 2019

An electronic nose (e‐nose) is a device that can detect and recognize odors and flavors using a sensor array. It has received considerable interest in the past decade because it is required in several areas such as health care, environmental monitoring, industrial applications, automobile, food storage, and military. However, there are still obstacles in developing a portable e‐nose that can be used for a wide variety of applications. For practical applications of an e‐nose, it is necessary to collect a massive amount of data from various sensing materials that can transduce interactions with molecules reliably and analyze them via pattern recognition. In addition, the possibility of miniaturizing the e‐nose and operating it with low power consumption should be considered. Moreover, it should work efficiently over a long period of time. To satisfy these requirements, several different chemoresistive material platforms including metal oxides, organics such as polymers and carbon‐based materials, and two‐dimensional materials were investigated as sensor elements for an e‐nose. As an individual material has limited selectivity, there is a continuing effort to improve the selectivity and gas sensing properties through surface decoration and compositional and structural variations. To produce a reliable e‐nose, which can be used for practical applications, researches in various fields have to be harmonized. This paper reviews the progress of research on e‐noses based on a chemoresistive gas sensor array and discusses the inherent challenges and potential solutions.
Metal halide perovskite nanocrystals and their applications in optoelectronic devices
Authors: Lu Po , Lu Min , Wang Hua , Sui Ning , Shi Zhifeng , Yu William W. , Zhang Yu
Published: August 2019

In recent years, metal halide perovskite nanocrystals (NCs) have been favored by many researchers due to their unique properties including long carrier diffusion length, high carrier mobility, tunable emission wavelength, and narrow full width at half maximum, making them great application potentials in optoelectronic devices. The photoluminescence quantum yields of perovskite NCs are nearly 100%, and the device efficiency of perovskite NC‐based light‐emitting diodes (LEDs) has been improved significantly from below 0.1% to over 20%. In addition, perovskite NC‐based solar cells and photodetectors have also developed rapidly in recent years. Here, we summarize the synthesis and the basic optoelectronic properties of metal halide perovskite NCs and introduce their applications in LEDs, solar cells, and photodetectors.
Challenges for the adoption of ICT for diabetes self‐management in South Africa
Authors: Petersen Fazlyn , Brown Afeefa , Pather Shaun , Tucker William D.
Published: August 2019

The increasing disease burden in developing countries inhibits the provision of quality care to citizens. However, the increased availability of information communication and technology (ICT) tools makes this a viable option for inclusion in primary health care. Even so, barriers are impeding the successful adoption and usage of ICT tools in health care contexts. This research focuses on one such context to identify the challenges and barriers for the adoption of ICT tools for diabetes self‐management in the Western Cape province of South Africa.

The extended technology acceptance model (TAM) and four factors (educational, technological, economic, and sociocultural factors) were identified as a basis for investigation. Evidence was gathered from a sample of 131 diabetic patients using semistructured interviews. These factors, together with TAM constructs, explore how patients interact with ICT and their attitudes towards the use of ICT for diabetes self‐management. The results indicate that all four factors form barriers to ICT adoption for diabetes self‐management. These findings provide a basis to inform how future interventions at the primary health care level may be developed to overcome the identified barriers in efforts to integrate ICT tools into diabetic patients' daily self‐management routines.
Distributed ledger technology and European Union General Data Protection Regulation compliance in a flexible working context
Authors: Rotondi Domenico , Saltarella Marco , Giordano Gaetano , Pellecchia Francesco
Published: August 2019

Compliance of distributed ledger technology (DLT) based solutions with the European Union General Data Protection Regulation (EU GDPR) is currently a hot topic both from a technical point of view, as well as from a legal and normative one. Flexible working is a new working model where employees can perform their work activity without specific time and space constraints. In this context privacy and information trustworthiness are relevant and, therefore, on the one hand it can gain benefit from using DLT based solutions, on the other hand it must comply with the GDPR. This paper describes a solution that combines DLTs and the new Ciphertext‐Policy Attribute Based Encryption cryptographic techniques to support compliance with the EU GDPR in the context of flexible working. The devised solution is being concretely experimented, in the context of the EU H2020 CITADEL project, by the Municipality of Bari (Italy).
A comparison of accumulated and distributed reinforcement periods with children exhibiting escape‐maintained problem behavior
Authors: Fulton Caitlin J. , Tiger Jeffrey H. , Meitzen Hannah M. , Effertz Hannah M.
Published: August 2019

Differential reinforcement is a common treatment for escape‐maintained problem behavior in which compliance is reinforced on a fixed‐ratio (FR) 1 schedule with brief access to positive and/or negative reinforcement. Recent research suggests some individuals prefer to complete longer work requirements culminating in prolonged (i.e. accumulated) reinforcement periods relative to brief (i.e. distributed) periods, but prolonged work exposure may evoke problem behavior and prevent compliance from contacting reinforcement when treating escape‐maintained problem behavior. We exposed 3 children with escape‐maintained problem behavior to both distributed (FR 1 resulting in 30 s of reinforcement) and accumulated (FR 15 resulting in 7.5 min of reinforcement) arrangements to compare their efficacy in maintaining low levels of problem behavior. We then assessed participants' preferences for these conditions in a concurrent‐chains arrangement. Accumulated‐reinforcement arrangements did not occasion additional problem behavior, but rather resulted in consistently lower levels of problem behavior for 2 of 3 participants. Participants demonstrated idiosyncratic preferences.
Food‐grade titanium dioxide (E171) by solid or liquid matrix administration induces inflammation, germ cells sloughing in seminiferous tubules and blood‐testis barrier disruption in mice
Authors: Rodríguez‐Escamilla Juan Carlos , Medina‐Reyes Estefany I. , Rodríguez‐Ibarra Carolina , Déciga‐Alcaraz Alejandro , Flores‐Flores José O. , Ganem‐Rondero Adriana , Rodríguez‐Sosa Miriam , Terrazas Luis I. , Delgado‐Buenrostro Norma L. , Chirino Yolanda I.
Published: August 2019

Food‐grade titanium dioxide labeled as E171 has been approved for human consumption by the Food and Drug Administration (USA) and by the European Union for five decades. However, titanium dioxide has been classified as a possible carcinogen for humans by the International Agency of Research in Cancer raising concerns of its oral intake and the translocation to bloodstream, which could disturb barriers such as the blood‐testis barrier. There is evidence that titanium dioxide by intragastric/intraperitoneal/intravenous administration induced alterations on testosterone levels, testicular function and architecture, but studies of the E171 effects on the testicle structure and blood‐testis barrier are limited. E171 is contained not only in foods in liquid matrix but also in solid ones, which can exert different biological effects. We aimed to compare the effects of E171 consumption in a solid matrix (0.1%, 0.5% and 1% in pellets) and liquid suspension (5 mg/kg body weight) on testis structure, inflammation infiltrate and blood‐testis barrier disruption of male BALB/c mice. Results showed that none of the administration routes had influence on body weight but an increase in germ cell sloughing and the infiltrate of inflammatory cells in seminiferous tubules, together with disruption of the blood‐testis barrier were similar in testis of both groups even if the dose received in mice in liquid matrix was 136 or 260 times lower than the dose reached by oral intake in solid E171 pellets in 0.5% E171 and 1% E171, respectively. This study highlights the attention on matrix food containing E171 and possible adverse effects on testis when E171 is consumed in a liquid matrix.
Fetal bovine serum impacts the observed N‐glycosylation defects in TMEM165 KO HEK cells
Authors: Vicogne Dorothée , Houdou Marine , Garat Anne , Climer Leslie , Lupashin Vladimir , Morelle Willy , Foulquier François
Published: August 2019

TMEM165 is involved in a rare genetic human disease named TMEM165‐CDG (congenital disorders of glycosylation). It is Golgi localized, highly conserved through evolution and belongs to the uncharacterized protein family 0016 (UPF0016). The use of isogenic TMEM165 KO HEK cells was crucial in deciphering the function of TMEM165 in Golgi manganese homeostasis. Manganese is a major cofactor of many glycosylation enzymes. Severe Golgi glycosylation defects are observed in TMEM165 Knock Out Human Embryonic Kidney (KO HEK) cells and are rescued by exogenous manganese supplementation. Intriguingly, we demonstrate in this study that the observed Golgi glycosylation defect mainly depends on fetal bovine serum, particularly its manganese level. Our results also demonstrate that iron and/or galactose can modulate the observed glycosylation defects in TMEM165 KO HEK cells. While isogenic cultured cells are widely used to study the impact of gene defects on proteins' glycosylation patterns, these results emphasize the importance of the use of validated fetal bovine serum in glycomics studies.
Time‐domain homogenization of multiturn windings based on RL Cauer ladder networks
Authors: Niyomsatian Korawich , Gyselinck Johan , Sabariego Ruth V.
Published: August 2019

This paper deals with the synthesis of an RL Cauer ladder network to homogenize multiturn windings in time‐domain finite element (FE) computations. In frequency domain, the macroscopic model of eddy currents in the winding can be described by frequency‐dependent complex impedance and reluctivity for skin and proximity effects respectively. To represent those in time domain, two RL Cauer networks are synthesized to match each, with the accuracy depending on the order of the network to be appended. The proposed method yields an improved accuracy as compared with the previous work in which the topology of the ladder network was not well chosen. The results are validated by means of a 2‐D axisymmetric inductor with a nonlinear gapped core.
Historical and future storm surge around New Zealand: From the 19th century to the end of the 21st century
Authors: Cagigal Laura , Rueda Ana , Castanedo Sonia , Cid Alba , Perez Jorge , Stephens Scott A. , Coco Giovanni , Méndez Fernando J.
Published: August 2019

We developed a new hindcast for storm surge at a 0.25° spatial scale for the whole New Zealand area using a statistical downscaling technique that links the mean local atmospheric conditions with the maximum storm surge levels at a daily scale. After validating the hindcast against sea level instrumental records from 17 tidal gauges around New Zealand, the same technique has been applied to obtain storm surge projections until 2,100 using different global climate models. The global climate models have been previously classified according to their ability to reproduce the past climatology in the studied area and seven models have been selected in order to explore their effect on storm surge projections. For the two representative Concentration Pathways studied, the projections indicate that the storm surge associated with the 50 years return period will increase in magnitude in the Southern areas while it will decrease in the Northern region. Even where a decreasing linear trend over the annual maxima is observed in the future time series, sporadic events of higher magnitude than the historical peaks can be.
Multi‐year assessment of atmospheric circulation and impacts on air temperature variation on James Ross Island, Antarctic Peninsula
Authors: Ambrožová Klára , Láska Kamil , Kavan Jan
Published: August 2019

The influence of synoptic‐scale circulation on air temperature variation in the ice‐free and glaciated areas on the eastern side of the Antarctic Peninsula (AP) has been analysed. For this purpose, a new classification of atmospheric circulation with 15 synoptic patterns in the AP region was developed using the self‐organizing maps technique. The synoptic patterns were compared with air temperature observations from coastal and glacial sites on James Ross Island, northeastern AP, in the period 2005–2015. The most frequent synoptic pattern with a frequency of 13.7% was dominated by a low‐pressure centre in the northwestern Bellingshausen Sea, which extended over the AP to the Weddell Sea. On the other hand, the largest inter‐annual variability was observed for a synoptic pattern with a low‐pressure centre in the southern Bellingshausen Sea. This synoptic pattern also had the highest air temperature anomalies at both investigated sites year‐round. Air temperature anomalies at the lower lying site (Mendel station) were the lowest during a high‐pressure ridge dominating the AP region due to a combination of local and synoptic‐scale processes. At Davies Dome, the glacial site, southerly barrier winds advecting cold air from the ice‐covered Weddell Sea during a strong low‐pressure system in the Weddell Sea ensured the coldest air temperature anomalies.
A new analytical method to measure S‐methyl‐l‐methionine in grape juice reveals the influence of yeast on dimethyl sulfide production during fermentation
Authors: Deed Rebecca C , Pilkington Lisa I , Herbst‐Johnstone Mandy , Miskelly Gordon M , Barker David , Fedrizzi Bruno
Published: August 2019

BACKGROUND

Dimethyl sulfide (DMS) is a small sulfur‐containing impact odorant, imparting distinctive positive and / or negative characters to food and beverages. In white wine, the presence of DMS at perception threshold is considered to be a fault, contributing strong odors reminiscent of asparagus, cooked cabbage, and creamed corn. The source of DMS in wine has long been associated with S‐methyl‐l‐methionine (SMM), a derivative of the amino acid methionine, which is thought to break down into DMS through chemical degradation, particularly during wine ageing.

RESULTS

We developed and validated a new liquid chromatography–tandem mass spectrometry (LC–MS/MS) method with a stable isotope dilution assay (SIDA) to measure SMM in grape juice and wine. The application of this new method for quantitating SMM, followed by the quantitation of DMS using headspace‐solid phase micro‐extraction coupled with gas chromatography–mass spectrometry (HS‐SPME/GC–MS), confirmed that DMS can be produced in wine via the chemical breakdown of SMM to DMS, with greater degradation observed at 28 °C than at 14 °C. Further investigation into the role of grape juice and yeast strain on DMS formation revealed that the DMS produced from three different Sauvignon blanc grape juices, either from the SMM naturally present or SMM spiked at 50 mmol L−1, was modulated depending on each of the four strains of Saccharomyces cerevisiae wine yeast used for fermentation.

CONCLUSION

This study confirms the existence of a chemical pathway to the formation of DMS and reveals a yeast‐mediated mechanism towards the formation of DMS from SMM during alcoholic fermentation. © 2019 Society of Chemical Industry
Untargeted metabolomics of strawberry (Fragaria x ananassa ‘Camarosa’) fruit from plants grown under osmotic stress conditions
Authors: Antunes Ana CN , Acunha Tanize dos S , Perin Ellen C , Rombaldi Cesar V , Galli Vanessa , Chaves Fabio C
Published: August 2019

BACKGROUND

Plants activate defense mechanisms to cope with adverse environmental conditions, leading to the accumulation and / or depletion of general and specialized metabolites. In this study, a multiplatform untargeted metabolomics strategy was employed to evaluate metabolic changes in strawberry fruit of cv. Camarosa grown under osmotic stress conditions. Liquid chromatography‐mass spectrometry (LC‐MS/MS) and gas chromatography‐mass spectrometry (GC‐MS) data from strawberries grown under two water‐deficit conditions, irrigated at 95% crop evapotranspiration (ETc) and 85% ETc, and one excess salt condition with a 80 mmol L−1 NaCl solution, were analyzed to determine treatment effects on fruit metabolism.

RESULTS

Multivariate principal component analysis, orthogonal projections to latent structures – discriminant analysis (OPLS‐DA), and univariate statistical analyses were applied to the data set. While multivariate analyses showed group separation by treatment, T‐tests and fold change revealed 12 metabolites differentially accumulated in strawberries from different treatments – among them phenolic compounds, glycerophospholipids, phytosterols, carbohydrates, and an aromatic amino acid.

CONCLUSION

Untargeted metabolomic analysis allowed for the annotation of compounds differentially accumulated in strawberry fruit from plants grown under osmotic stress and non‐stressed plants. The metabolic disturbance in plants under stress involved metabolites associated with the inhibition of reactive oxygen species and cell‐wall and membrane lipid biosynthesis, which might serve as osmotic stress biomarkers. © 2019 Society of Chemical Industry
Dynamic interaction of tourism, finance, and institutions in explaining growth in Asia's little dragon economies
Authors: Tang Chor Foon , Salman Asma , Abosedra Salah
Published: August 2019

This study attempts to investigate the role of institutions in enhancing the effect of tourism and financial development on economic growth in Asia using a panel sample from 1984 to 2016. Our findings reveal that tourism and finance are two important variables accountable for growth in our selected countries. Furthermore, our empirical results suggest that their effects on growth are enhanced by the level of institutional quality. Therefore, institutional reforms should thus precede tourism attraction and financial development policies used in these countries in an effort to enhance the benefits from the tourism and financial sector development on growth.