bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photocurrents in crystal‐amorphous hybrid stannous oxide/alumina binary nanofibers
Authors: Ling JinKiong , Pal Bhupender , Chong KwokFeng , Schmidt‐Mende Lukas , Bisquert Juan , Jose Rajan 
Published: April 2019

AbstractSuppression of charge recombination by thin amorphous alumina layers on metal oxide semiconductors has demonstrated a vital role in electronic appliances beside its role as an insulator. This study reports effect of amorphous alumina (Al2O3) on the structural, electrical, and optical properties of stannous oxide (SnO2). The samples for the present study are prepared as nanofibers by electrospinning a polymeric solution containing aluminum and stannous precursors and subsequent annealing; six samples with varying concentrations of aluminum and stannous are considered. A crystal‐amorphous SnO2/Al2O3 hybrid system was confirmed by both XRD and XPS analysis. Both BET and Mott‐Schottky analysis showed increase in the surface area and conduction band minimum of the sample with increase in the Al content, however, at the expense of its electrical conductivity. The electron lifetime of the sample increased with increase in the Al content, but the electron transport time increase with decrease in the electrical conductivity of the sample. Both Urbach energy measurement and Stoke's shift showed generation of deeper trap state with increase in the Al content. Investigation on sample photovoltaic performance showed that the loss in electrical conductivity of the sample can be compensated by the improved surface area to a certain extent. Interestingly, a composite nanofiber containing equal molar fraction of aluminum and stannous showed orders of magnitude higher photocurrent despite its similar resistivity as that of pure alumina fibers, which is shown to originate from a Fermi energy gradient at the Al2O3/SnO2 interface.
Improved magnetic and electromagnetic absorption properties of xSrFe12O19/(1−x)NiFe2O4 composites
Authors: Liu Yin , Wang Zhecheng , Zhao Li , Zhou Jun , Wang Yueqin 
Published: April 2019

AbstractxSrFe12O19/(1−x)NiFe2O4 composites (0 ≤ x ≤ 1.0) were synthesized by using a conventional solid‐state synthetic route. The results show that magnetic hysteresis loops of the xSrFe12O19/(1−x)NiFe2O4 composites are similar to those of individual component ferrites, except for the 0.1SrFe12O19/0.9NiFe2O4 and 0.3SrFe12O19/0.7NiFe2O4, suggesting that the hard/soft magnetic phases are well exchange‐coupled. The saturation magnetization, coercivity, and remanent magnetization of the xSrFe12O19/(1−x)NiFe2O4 composites are increased with increasing content of SrFe12O19, with maximal values of 42.1 Am2 kg−1, 78.7 kA m−1, 17.2 Am2 kg−1, respectively, as the content x is about 0.5. They are higher than those of the individual components, implying that interface coupling is present in the magnetic composites. The coercivity and remanent magnetization of the composites are increased initially with increasing sintering temperature and then show a downward tendency. For the component SrFe12O19 and NiFe2O4, the minimum reflection losses are −12.5 dB and −18.3 dB at match thicknesses of 2.5 mm and 2 mm, respectively. Compared with those of the component SrFe12O19 and NiFe2O4, the microwave absorption performances of the xSrFe12O19/(1−x)NiFe2O4 composites are improved remarkably, especially for the samples of x = 0.3 and x = 0.9. The minimum reflection losses values of the 0.3SrFe12O19/0.7NiFe2O4 composite are −31.6 dB (12.7 GHz) and −20.2 dB (13 GHz), while those of the 0.9SrFe12O19/0.1NiFe2O4 composites are −23.7 dB (16.3 GHz) and −33.5 dB (15.8 GHz), as the matching thicknesses are 2.5 mm and 2 mm, respectively. Therefore, the xSrFe12O19/(1−x)NiFe2O4 composites could be used as potential microwave absorption materials.
Zero stress aging in notched multi‐component glass fibers
Authors: Van Sant Joseph , Diercks David , Fett Theo , Reimanis Ivar E. 
Published: April 2019

AbstractDegradation of glass under zero applied load in the presence of humidity at ambient temperature is of great interest to the container and fiber glass industries. The phenomenon is well documented for fused silica used in optical fibers, but has not been studied in detail for multi‐component glasses. In this work notches of varying length (500‐1500 nm) were placed with a focused ion beam into two types of multi‐component glass fibers, E‐glass (48 μm diameter) and soda‐lime‐silicate (35 μm diameter). Notched specimens were exposed to dry and humid conditions for up to 32 days. Transmission electron microscopy revealed the presence of extensive reaction products within the root of the notch, even after only 1 day of aging in the nominally dry environment for the soda‐lime‐silicate glass. Surprisingly, the extensive reactions have no measurable effect on the fiber strength. The uniaxial tensile strength of the notched glass fibers, measured with the fracture surface mirror radius method, does not follow a classic fracture mechanics prediction, implying that the notches are not classic Griffith flaws. Fracture mechanics is applied to show that sharpness at the notch base may be important, especially when subcritical crack growth is present during the strength measurement.
Structure and microwave dielectric characteristics of Sr2[Ti1−x(Al0.5Nb0.5)x]O4 (x ≤ 0.50) ceramics
Authors: Hameed Iqra , Wu Shu Ya , Li Lei , Liu Xiao Qiang , Chen Xiang Ming 
Published: April 2019

AbstractSr2[Ti1−x(Al0.5Nb0.5)x]O4 (x = 0, 0.10, 0.25, 0.30, 0.5) ceramics were synthesized by a standard solid‐state reaction process. Sr2[Ti1−x(Al0.5Nb0.5)x]O4 solid solutions with tetragonal Ruddlesdon‐Popper (R‐P) structure in space group I4/mmm were obtained within x ≤ 0.50, and only minor amount (1‐2 wt%) of Sr3Ti2O7 secondary phase was detected for the compositions x ≥ 0.25. The temperature coefficient of resonant frequency τf of Sr2[Ti1−x(Al0.5Nb0.5)x]O4 ceramics was significantly improved from 132 to 14 ppm/°C correlated with the increase in degree of covalency (%) with increasing x. The dielectric constant ɛr decreased linearly with increasing x, while high Qf value was maintained though it decreased firstly. The variation tendency of Qf value was dependent on the trend of packing fraction combined with the microstructure. Good combination of microwave dielectric properties was achieved for x = 0.50: ɛr = 25.1, Qf = 77 580 GHz, τf = 14 ppm/°C. The present ceramics could be expected as new candidates of ultra‐high Q microwave dielectric materials without noble element such as Ta.
Multiple colonizations, hybridization and uneven diversification in Cyrtandra (Gesneriaceae) lineages on Hawai'i Island
Authors: Johnson Melissa A. , Pillon Yohan , Sakishima Tomoko , Price Donald K. , Stacy Elizabeth A. 
Published: April 2019

AbstractAimThe diversity and composition of species pools within oceanic archipelagos is determined by a combination of colonization, abiotic tolerance, in situ diversification, biotic interactions and extinction. The signature of biogeographic events and evolutionary processes, however, may be masked by recent coalescence and hybridization between closely related species. We used the species‐rich plant genus Cyrtandra (Gesneriaceae) to investigate the roles of colonization and hybridization in shaping community assemblages on the geologically young Hawai'i Island.LocationHawaiian Islands.TaxonCyrtandra (Gesneriaceae).MethodsWe sampled 29 Cyrtandra taxa and putative hybrids across the main Hawaiian Islands and generated single nucleotide polymorphisms (SNPs) from nine single‐copy nuclear genes. Maximum likelihood and Bayesian inference were used to reconstruct phylogenetic relationships, divergence times were estimated using secondary calibrations and island ages, and ancestral area estimation was done using likelihood models. Lastly, we used a Bayesian population assignment test and principal components analysis to infer population genetic structure.ResultsCyrtandra colonization of the main Hawaiian Islands appears to have followed the progression rule, whereby the oldest high Hawaiian Islands (Kaua'i and O'ahu) were colonized first, followed by colonization of the younger islands as habitat became available. Hawai'i Island was colonized four times, with two dispersal events from O'ahu and two from Maui Nui. The different colonization events gave rise to significantly uneven numbers of species, and hybridization among the incipient lineages was detected in the form of intermediate genotypes.Main conclusionsOur investigation into community assembly in a species‐rich plant genus on a geologically young oceanic island revealed a history of multiple colonizations and hybridization among colonizing lineages. The rapid diversification (3.5 species/My) of one of four Cyrtandra lineages on Hawai'i Island may be the result of hybridization between genetically diverse lineages that stem from independent colonization events. Multiple colonization events followed by a merging of lineages may be particularly common during early‐stage community assembly on islands and, through the generation of genetic variation, may be especially important for species diversification.
The psychological and aesthetic impact of age‐related hair changes in females
Authors: Ahluwalia Jusleen , Fabi Sabrina G. 
Published: April 2019

AbstractBackgroundWhile dermatologists focus on practices to promote anti‐aging, thinning hair that frames a more rejuvenated face can affect age perception and cosmesis.ObjectivesTo characterize the effects of age‐related hair changes on age determination and perceived attractiveness.MethodsA search was conducted for articles on intrinsic and extrinsic aging as it relates to hair. Key studies on the hair aging process and its effects on self‐perception, confidence, and anti‐aging were reviewed.ResultsAccording to several studies, hair density peaks about 27 years of age or earlier and then decreases from the mid‐thirties onward. This serves as an opportunity to prevent or treat hair loss in a similar way we treat aging skin. Without optimizing appearance of hair, overall cosmesis to foster self‐perception can be curtailed despite multiple efforts to rejuvenate and restore the aging face.ConclusionThe discrepancy between rejuvenated faces and thinner appearing hair that frames the face highlights the importance of a holistic approach to the anti‐aging consultation. To more comprehensively address the aesthetic patient, we need to promote awareness of the onset of these hair changes in order to incorporate prevention and therapeutic strategies to preserve hair to complement overall appearance.
Tadpoles modulate antipredator responses according to the abundance of vegetation experienced during the embryonic stage
Authors: Lucon‐Xiccato T. 
Published: April 2019

AbstractBecause of the selection pressures imposed by predation and the costs of antipredator responses, prey often exhibit phenotypically plastic behavioural defences that vary with risk level. For anuran larvae, the presence of vegetation is a critical environmental factor that predicts predation risk: in habitats with abundant vegetation, tadpoles are much less likely to be caught by fish and invertebrate predators. Hence, tadpoles might display the ability to match their antipredator behaviour with the amount of vegetation in the environment. I investigated this hypothesis by comparing the acute antipredator responses of tadpoles experimentally raised under high‐vegetation and low‐vegetation treatment from the egg stage. To address at which developmental stage the behavioural plasticity appeared, I additionally tested two groups of tadpoles that switched from a high‐ to low‐vegetation habitat and vice versa soon after hatching. I observed a stronger antipredator response in tadpoles that experienced the environment with abundant vegetation at the embryonic stage. The environment experienced during the larval stage did not affect the tadpoles' antipredator behaviour. The direction of the observed plasticity aligns with the prediction of the risk allocation model. Therefore, my study seems to support the hypothesis that tadpoles can tune their antipredator behaviour not only based on the direct risk experienced (i.e. the number of predatory attacks) but also based on vegetation, an environmental factor that indirectly predicts predation risk.
More yellow more toxic? Sex rather than alkaloid content is correlated with yellow coloration in the fire salamander
Authors: Preißler K. , Gippner S. , Lüddecke T. , Krause E. T. , Schulz S. , Vences M. , Steinfartz S. 
Published: April 2019

AbstractPrey species signalling their toxicity to potential predators via conspicuous coloration occur frequently in nature. This survival strategy, called aposematism, is thought to be successful when based on honest qualitative or quantitative signalling of toxicity and predator learning behaviour. However, evidence supporting these basic assumptions is absent for most species considered aposematic. Due to their conspicuous black and yellow coloration – in combination with the production of toxic steroidal alkaloids – fire salamanders (genus Salamandra) are textbook examples of aposematism; but whether this signal combination meets the requirements to be considered aposematic in a strict sense remains unclear. We therefore tested one assumption that would support aposematism in this species, that is, whether the alkaloid content is honestly correlated with their warning coloration. We studied fire salamanders (Salamandra salamandra terrestris) from different locations in the Solling, an area in Lower Saxony (Germany) known for individuals with high dorsal yellow ratios. We measured the dorsal yellow ratio of 50 individuals from each of three populations, and quantified toxicity (steroidal alkaloid content of the parotoid glands) of twelve individuals per location. We then analysed the correlation between the yellow ratio and various parameters (alkaloid content, sex, and location), as well as the interactions between these. We found no correlation between yellow ratio and toxicity; instead yellow coloration was significantly affected by sex (males displaying more yellow), and location. Our data suggest that besides possibly serving as warning coloration in a toxic species, the conspicuous colour pattern of the fire salamander might be further shaped by sexual selection and genetic drift. Thus, unravelling the effects of coloration in the context of aposematism might not be possible without disentangling the various other influences acting on coloration as a whole.
Simplicity and Language: Bonaventure's Semiotic Asymptoticism
Authors: Luy David 
Published: April 2019

AbstractLuy engages in a close reading of Bonaventure's doctrine of divine simplicity. He offers this reading in light of a keen awareness of contemporary critiques of the doctrine, especially from philosophers of religion who suggest that divine simplicity either means that our human words really cannot say anything intelligible about God, or that divine properties that are surely distinct (such as justice and goodness) are in fact absolutely identical. In sum, Luy recognizes that the doctrine of simplicity challenges the intelligibility of religious language. He points out that medieval thinkers, too, recognized this challenge, but they regarded it as a salutary reminder that God is ultimately incomprehensible to finite minds, even though we can speak true things about God. In expositing divine simplicity according to Bonaventure, Luy shows that Bonaventure expects that creation itself is designed to reveal God's limitless self‐communication. Divine simplicity, then, serves to affirm divine perfection, in a manner limited by the effort of finite words to express the infinite; but divine simplicity also reflects the “semiotic universe” that allows for, and exalts in, the wondrous expression of the divine plenitude.
AtEDT1/HDG11 regulates stomatal density and water‐use efficiency via ERECTA and E2Fa
Authors: Guo Xiao‐Yu , Wang Yao , Zhao Ping‐Xia , Xu Ping , Yu Guo‐Hua , Zhang Li‐Yong , Xiong Yan , Xiang Cheng‐Bin 
Published: April 2019

Summary

Improvement of crop drought resistance and water‐use efficiency (WUE) has been a major endeavor in agriculture. Arabidopsis ENHANCED DROUGHT TOLERANCE1/HOMEODOMAIN GLABROUS11 (AtEDT1/HDG11), a homeodomain‐START transcription factor we previously identified from the enhanced drought tolerance1 mutant (edt1), has been demonstrated to improve drought tolerance and WUE significantly in multiple plant species when constitutively overexpressed.

Here, we report the genetic evidence suggesting a genetic pathway, which consists of EDT1/HDG11, ERECTA, and E2Fa loci, and regulates WUE by modulating stomatal density. AtEDT1/HDG11 transcriptionally activates ERECTA by binding to homeodomain‐binding (HD) cis‐elements in the ERECTA promoter. ERECTA, in turn, depends on E2Fa to modulate the expression of cell cycle‐related genes.

This modulation affects the transition from mitosis to endocycle, leading to increased ploidy levels in leaf cells, and therefore increased cell size and decreased stomatal density.

Our results suggest a possible EDT1/HDG11‐ERECTA‐E2Fa genetic pathway that reduces stomatal density by increasing cell size and provide a new avenue to improve WUE of crops.
Energy costs of salt tolerance in crop plants
Authors: Munns Rana , Day David A. , Fricke Wieland , Watt Michelle , Arsova Borjana , Barkla Bronwyn J. , Bose Jayakumar , Byrt Caitlin S. , Chen Zhong‐Hua , Foster Kylie J. , Gilliham Matthew , Henderson Sam W. , Jenkins Colin L. D. , Kronzucker Herbert J. , Miklavcic Stanley J. , Plett Darren , Roy Stuart J. , Shabala Sergey , Shelden Megan C. , Soole Kathleen L. , Taylor Nicolas L. , Tester Mark , Wege Stefanie , Wegner Lars H. , Tyerman Stephen D. 
Published: April 2019

SummaryAgriculture is expanding into regions that are affected by salinity. This review considers the energetic costs of salinity tolerance in crop plants and provides a framework for a quantitative assessment of costs. Different sources of energy, and modifications of root system architecture that would maximize water vs ion uptake are addressed. Energy requirements for transport of salt (NaCl) to leaf vacuoles for osmotic adjustment could be small if there are no substantial leaks back across plasma membrane and tonoplast in root and leaf. The coupling ratio of the H+‐ATPase also is a critical component. One proposed leak, that of Na+ influx across the plasma membrane through certain aquaporin channels, might be coupled to water flow, thus conserving energy. For the tonoplast, control of two types of cation channels is required for energy efficiency. Transporters controlling the Na+ and Cl− concentrations in mitochondria and chloroplasts are largely unknown and could be a major energy cost. The complexity of the system will require a sophisticated modelling approach to identify critical transporters, apoplastic barriers and root structures. This modelling approach will inform experimentation and allow a quantitative assessment of the energy costs of NaCl tolerance to guide breeding and engineering of molecular components.
Dynamic panel modelling of electricity consumption and Economic Community of West African States (ECOWAS)
Authors: Inuwa Nasiru , Adamu Sagir , Saidu Abubakar Mohammed , Sani Muhammad Bello 
Published: April 2019

AbstractThe effect of electricity consumption on economic growth of the Economic Community of West African States (ECOWAS) Member Countries has been examined during the period 2007–2016. The study applied both static and dynamic panel models in the form of Fixed‐Effect, Random‐Effect, Difference GMM and System GMM. The results revealed that electricity consumption has a positive and statistically significant impact on economic growth for both static and dynamic panel models. Capital has also been found to have impacted positively and significantly on economic growth in both models. Similarly, labour showed a positive and significant impact on economic growth system GMM model only. Since the study supports electricity consumption led‐growth hypothesis, therefore, it is recommended that ECOWAS countries should explore other alternative sources of electricity generation in order to ensure sufficient and reliable supply of electricity. This can be achieved at individual country level by utilising the potentials of renewable endowments such as biomass, biofuels and solar energy available to each country. Equally, the regional efforts to establish West African Power Pool (WAPP) and West African Gas Pipeline (WAGP) in order to increase the supply as well as grid reliability should be strengthened.
The value of multidisciplinary team in syncope clinic for the effective diagnosis of complex syncope
Authors: Qian Xiao‐lin , Pan Ye‐sheng , Chen Jing‐jiong , Jiang Qing‐qing , Huang Dong , Li Jing‐bo 
Published: April 2019

AbstractBackgroundSyncope is a perplexing challenge that often receives thorough evaluation, yet the diagnosis remains unclear. Usually, the emergency department is the first point at which patients present with syncope. However, diverse medical factors, including low diagnostic rates and inconsistent management by doctors, add to healthcare costs and delay diagnosis for syncope patients.MethodsPatients who had been to the emergency department at least once but were not given a clear diagnosis of syncope were recruited into our study at the time they visited syncope clinic staffed by a multidisciplinary team. Complete medical histories and clinical examinations were conducted by both experienced cardiologists and neurologists. If patients were not given a conclusive diagnosis at the syncope clinic on the basis of outpatient examinations, they were admitted for further evaluation.ResultsA total of 209 consecutive patients claiming “syncope” visited the syncope clinic, yet only 167 patients were formally diagnosed with syncope. For these 167 patients, the mean age was 55.93 ± 17.40 years old, and 41.3% were male. The proportions of cardiac syncope, reflex syncope, orthostatic hypotension (OH), and syncope of uncertain etiology were 19.8%, 64.1%, 7.8%, and 8.4%, respectively. The diagnostic rate was 91.6%, and the hospitalization rate was 23.4%. Patients with reflex syncope and OH were younger than patients with cardiac syncope. Cardiac syncope tends to occur more frequently in males, while reflex syncope is more likely in females.ConclusionsThe cooperation of professional cardiologists and neurologists will play an important role in improving diagnostic rates, lowering admission rates, and reducing medical costs.
Transferring emotional capital as coerced discretion: Street‐level bureaucrats reconciling structural deficiencies
Authors: Lavee Einat , Strier Roni 
Published: April 2019

AbstractThe discretion of street‐level bureaucrats (SLBs) plays a key role in policy implementation. This study offers a new perspective on the meaning of discretion under social policy reforms, which created new structural deficiencies in the work of SLBs and have raised expectations of policy implementation without offering sufficient policy responses. Under such conditions, the discretion of SLBs should be understood as coerced, more so than as a positive element of freedom and choice. As such, SLBs are forced to employ informal practices and provide alternative resources for their clients. Findings indicate a transference of emotional resources from SLBs to clients, aimed at achieving policy outcomes of economically independent citizens, paradoxically accompanied by an awareness of powerful barriers to such conversion. The study contributes both to the understanding of discretion in policy implementation, in the context of an expanding public service gap, and to theories of emotion manifestation in public administration.