bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards understanding intrinsic degradation and breakdown mechanisms in SiOCH low-k dielectrics
Authors: Wu C. , Li Y. , Ciofi I. , Kauerauf Th. , Bömmels J. , De Wolf I. , Tőkei Zs. , Croes K.
Published: February 2015

The degradation and breakdown mechanisms of a SiOCH low-k material with k = 2.3 (25% porosity) and thicknesses ranging from 90 nm to 20 nm were investigated. By combining the time dependent dielectric breakdown data at positive/negative bias stress with the thickness scaling results, dielectric failure is proven to be intrinsic and not influenced by copper drift or metal barrier deposition induced dielectric damage. It is shown that stress induced leakage current (SILC) can be used as a measure of dielectric degradation. Therefore, low field lifetimes can be safely estimated using SILC extrapolation. Based on our results, both the impact damage model and the power law model have a good accuracy for low field lifetime prediction. Recovery and anneal experiments are used to study the physical nature causing the observed negative flatband voltage shifts in our metal-insulator-semiconductor planar capacitor structures, where hydrogen induced unstable fast and slow donor type interface states are hypothesized to be the root cause of the observed shifts. We suggest that atomic hydrogen is released from the dielectric during electron injection and migrates to the interfacial region. Our model is further supported by an observed irreversible SILC change during the recovery and anneal studies. The degradation mechanism proposed in this work, supported by the low field lifetime data, provides a feasible explanation for intrinsic low-k dielectric failure.
Synthesis, characterization of WS2 nanostructures by vapor phase deposition
Authors: Fan Yinping , Li Jun , Hao Guolin , Luo Siwei , Tang Chao , Zhong Jianxin
Published: February 2015

Ultrathin two-dimensional WS2 nanostructures with various morphologies have been prepared on SiO2/Si (300 nm) and sapphire substrates by vapor phase deposition method. Simultaneously, tungsten nanostructures have also been obtained during the growth process. The nanostructures and morphologies of as-prepared products were systematically characterized by employing atomic force microscopy, Raman spectroscopy as well as scanning electron spectroscopy. The electrostatic properties of WS2 nanostructures were investigated exhibiting uniform surface potential and charge distributions. We have also detected the photoluminescence properties of WS2 nanostructures, which are dependent on the thickness and nanostructures of synthesized WS2. These results suggest that the optoelectronic properties of WS2 nanostructures can be effectively tuned by quantum confinement effect and nanostructures.
Dewetting and detachment of Pt nanofilms on graphitic substrates: A molecular dynamics study
Authors: Li Yanru , Tang Chao , Zhong Jianxin , Meng Lijun
Published: February 2015

We have investigated the dynamics of dewetting and detachment of nanoscale platinum (Pt) films on graphitic substrates using molecular dynamics (MD). For the thinner Pt nanofilms (<0.6 nm), nanoscale holes are formed randomly during the dewetting process because of the strong interaction between the Pt films and substrate. In contrast, for the thicker Pt nanofilms (>0.6 nm), nanodroplets are formed directly. Interestingly, the nanodroplets can detach from the substrate and the detachment velocity (vd) increases and then decreases as the film gets thicker. We have analyzed the dependence of the detachment velocity on the thickness of the nanofilm by considering the conversion of surface energy to the kinetic energy of a droplet. In addition, the effect of temperature on the dewetting and detachment behavior of the Pt films is also discussed. Our results show that vd increases monotonically with temperature. These results are important for understanding the dewetting and detachment dynamics of metal films on solid substrates.
Multiple logic functions from extended blockade region in a silicon quantum-dot transistor
Authors: Lee Youngmin , Lee Sejoon , Im Hyunsik , Hiramoto Toshiro
Published: February 2015

We demonstrate multiple logic-functions at room temperature on a unit device of the Si single electron transistor (SET). Owing to the formation of the multi-dot system, the device exhibits the enhanced Coulomb blockade characteristics (e.g., large peak-to-valley current ratio ∼200) that can improve the reliability of the SET-based logic circuits. The SET displays a unique feature useful for the logic applications; namely, the Coulomb oscillation peaks are systematically shifted by changing either of only the gate or the drain voltage. This enables the SET to act as a multi-functional one-transistor logic gate with AND, OR, NAND, and XOR functions.
Magnetotransport phenomena in Bi2Se3 thin film topological insulators grown by hybrid physical chemical vapor deposition
Authors: Kumar Raj , Brom Joseph E. , Redwing Joan M. , Hunte Frank
Published: February 2015

Intrinsic defects in Bi2Se3 topological insulators tend to produce a high carrier concentration and current leakage through the bulk material. Bi2Se3 thin films were grown by hybrid physical chemical vapor deposition on (0001) Al2O3 substrates with high Se vapor pressure to reduce the occurrence of Se vacancies as the main type of defect. Consequently, the carrier concentration was reduced to ∼5.75 × 1018 cm−3 comparable to reported carrier concentration in Bi2Se3 thin films. Magnetotransport measurements were performed on the films and the data were analyzed for weak anti-localization using the Hikami-Larkin-Nagaoka model. The estimated α and lϕ values showed good agreement with the symplectic case of 2-D transport of topological surface states in the quantum diffusion regime. The temperature and angular dependence of magnetoresistance indicate a large contribution of the 2-D surface carriers to overall transport properties of Bi2Se3 thin film.
Photoconductive properties of Bi2S3 nanowires
Authors: Andzane J. , Kunakova G. , Varghese J. , Holmes J. D. , Erts D.
Published: February 2015

The photoconductive properties of Bi2S3 nanowires synthesized inside anodized alumina (AAO) membrane have been characterized as a function of illuminating photon energy between the wavelengths of 500 to 900 nm and at constant illumination intensity of 1–4 μW·cm−2. Photoconductivity spectra, photocurrent values, photocurrent onset/decay times of individual Bi2S3 nanowires liberated from the AAO membrane were determined and compared with those of arrays of as-produced Bi2S3 nanowires templated inside pores of AAO membrane. The alumina membrane was found to significantly influence the photoconductive properties of the AAO-hosted Bi2S3 nanowires, when compared to liberated from the AAO membrane individual Bi2S3 nanowires, possibly due to charge carrier trapping at the interface between the nanowire surface and the pore walls.
Controlling the transparency window in terahertz band using mode coupling metamaterials
Authors: Qiao Shen , Zhang Yaxin , Xu Gaiqi , Sun Linlin , Sun Han , Li Ling , Liang Shixiong , Zhao Yuncheng , Yang Ziqiang
Published: February 2015

Mode-coupling metamaterials are typically composite structures with different resonance modes. Controlling couplings among these modes results in a sharp transparency window within the absorption spectrum of the metamaterials. Here, we present a composite structure of ring and split-ring resonators to constitute a new structure with entirely new mode. Experimental results show that the asymmetric combination of these resonators can result in a variation in transparency strength. The dimensions and relative positions of the split-ring resonator are discussed particularly with a series of experimental results. Simulation results show that the coupling intensity is the main reason for this behavior. Exploiting this aspect, a way to control the transparency window between composite structure metamaterials is proposed.
Confirmation of chloride deficiency as the cause of leaf spotting in durum wheat grown in the Australian northern grains region
Authors: Schwenke G. D. , Simpfendorfer S. R. , Collard B. C. Y.
Published: February 2015

During the 2007 winter cropping season in Australia, severe leaf-spotting (necrosis) symptoms resembling chloride (Cl–) deficiency found in North America were reported in the newly released durum wheat variety Jandaroi. Testing for bacterial, fungal and viral pathogens all proved negative. Four Australian durum and four Australian bread wheat varieties were grown, along with a North American variety of each, in a glasshouse experiment using a sterile sand–vermiculite mix and nutrient solutions containing 0 (nil), 0.5, 1.0 or 2.0 mm Cl–. When grown in the nil Cl– solution, all durum and some bread wheat varieties produced leaf-spotting symptoms the same as observed in the field. Nil Cl– also delayed flowering, reduced biomass, decreased grain size, and depressed grain yield in most durum and bread wheat varieties. In field experiments, additions of Cl– fertiliser as KCl at sowing provided no biomass or yield response from a range of wheat varieties, probably because the plants accessed sufficient Cl– from below 0.9 m depth in the soil. Chloride concentrations in whole-plant tissue sampled at head emergence suggested that unfertilised plants were borderline deficient in Cl– according to critical values established in North America. An in-crop foliar Cl– application experiment showed linear uptake of applied Cl–, as MgCl2, until the end of tillering. However, because leaf-spotting symptoms typically appear only after tillering, it is not possible to correct Cl– deficiency by adding Cl– fertiliser to the affected crop after symptoms appear. Managing Cl– in susceptible crops therefore needs to be preventative rather than curative. Among commercial varieties, Jandaroi was highly sensitive to low Cl–, Caparoi was moderately sensitive, and EGA Bellaroi was tolerant. Several elite durum breeding lines grown in 2010 showed considerably reduced leaf spotting compared with Jandaroi under low Cl– conditions, indicating potential for conventional breeding to reduce the potential impact of low Cl– soils on durum production in northern Australia.
The ameliorating effects of biochar and compost on soil quality and plant growth on a Ferralsol
Authors: Agegnehu Getachew , Bird Michael I. , Nelson Paul N. , Bass Adrian M.
Published: February 2015

Deteriorating soil fertility and the concomitant decline in agricultural productivity are major concerns in many parts of the world. A pot experiment was conducted with a Ferralsol to test the hypothesis that application of biochar improves soil fertility, fertiliser-use efficiency, plant growth and productivity, particularly when combined with compost. Treatments comprised: untreated control; mineral fertiliser at rates of 280 mg nitrogen, 70 mg phosphorus and 180 mg potassium pot–1 (F); 75% F + 40 g compost pot–1 (F + Com); 100% F + 20 g willow biochar pot–1 (F + WB); 75% F + 10 g willow biochar + 20 g compost pot–1 (F + WB + Com); 100% F + 20 g acacia biochar pot–1 (F + AB); and 75% F + 10 g acacia biochar + 20 g compost pot–1 (F + AB + Com). Application of compost with fertiliser significantly increased plant growth, soil nutrient status and plant nutrient content, with shoot biomass (as a ratio of control value) decreasing in the order F + Com (4.0) > F + WB + Com (3.6) > F + WB (3.3) > F + AB + Com (3.1) > F + AB (3.1) > F (2.9) > control (1.0). Maize shoot biomass was positively significantly correlated with chlorophyll content, root biomass, plant height, and specific leaf weight (r = 0.99, 0.98, 0.96 and 0.92, respectively). Shoot and root biomass had significant correlations with soil water content, plant nutrient concentration, and soil nutrient content after harvesting. Principal component analysis (PCA) showed that the first component provided a reasonable summary of the data, accounting for ~84% of the total variance. As the plants grew, compost and biochar additions significantly reduced leaching of nutrients. In summary, separate or combined application of compost and biochar together with fertiliser increased soil fertility and plant growth. Application of compost and biochar improved the retention of water and nutrients by the soil and thereby uptake of water and nutrients by the plants; however, little or no synergistic effect was observed.
Metabolic resting-state brain networks in health and disease
Authors: Spetsieris Phoebe G. , Ko Ji Hyun , Tang Chris C. , Nazem Amir , Sako Wataru , Peng Shichun , Ma Yilong , Dhawan Vijay , Eidelberg David
Published: February 2015

Significance

We present an innovative approach to evaluate default mode network (DMN) activity in individual subjects using metabolic imaging. After characterizing a distinct set of metabolic resting state networks (RSNs) in healthy subjects, network activity was tracked over time in patients with neurodegenerative disorders, such as Parkinson’s disease and Alzheimer’s disease. We found that the dominant normal metabolic RSN, which corresponded to the DMN, is preserved in early-stage Parkinson’s disease patients. Although significant DMN reductions developed later, these changes were reversible in part by dopamine treatment. This finding contrasts with Alzheimer’s disease, in which DMN loss is rapid and continuous, beginning before clinical diagnosis. Metabolic imaging can provide a versatile, quantitative means of assessing brain disease at the network level.
Coincidence avoidance principle in surface haptic interpretation
Authors: Manuel Steven G. , Klatzky Roberta L. , Peshkin Michael A. , Colgate James Edward
Published: February 2015

Significance

When multiple fingertips experience force sensations during movement, how does the brain decide whether to interpret the forces separately or as an integrated whole? To investigate this question, a force feedback device was used to display forces to two fingertips as they moved collinearly. The force patterns on each finger were constructed to produce illusory virtual bumps, and the distance between these bumps was varied across trials. When bump and finger spacing were identical, subjects tended to report only one bump. This result suggests that the brain selects interpretations of touch sensations that rely on the fewest coincidental alignments between the fingertips and environmental features. This result also has significance for the design of advanced multitouch displays with haptic feedback.
Etiology of distinct membrane excitability in pre- and posthearing auditory neurons relies on activity of Cl
−
channel TMEM16A
Authors: Zhang Xiao-Dong , Lee Jeong-Han , Lv Ping , Chen Wei Chun , Kim Hyo Jeong , Wei Dongguang , Wang Wenying , Sihn Choong-Ryoul , Doyle Karen Jo , Rock Jason R. , Chiamvimonvat Nipavan , Yamoah Ebenezer N.
Published: February 2015

Significance

One of the major issues in auditory neuroscience is the mechanism by which the developing hair cells and spiral ganglion neurons (SGNs) transition from prehearing characteristics to posthearing features. For decades it was thought that spontaneous action potentials in SGNs emanate from spontaneously firing prehearing hair cells. Here, we demonstrate that developing SGNs use Ca
2+
-activated Cl
−
conductance to depolarize the resting membrane potential and to prime the neurons in a hyperexcitable prehearing state. Moreover, SGNs undergo global changes in intracellular Cl
−
homeostasis to alter their coding properties during development. Our findings address the endogenous origin of spontaneous activity in SGNs, transcend auditory-neuron-specific phenomena, and could open the flood gate for investigation on the mechanisms of Cl
−
regulation in systems neuroscience.
MmTX1 and MmTX2 from coral snake venom potently modulate GABA
A
receptor activity
Authors: Rosso Jean-Pierre , Schwarz Jürgen R. , Diaz-Bustamante Marcelo , Céard Brigitte , Gutiérrez José M. , Kneussel Matthias , Pongs Olaf , Bosmans Frank , Bougis Pierre E.
Published: February 2015

Significance

In this study, we report the identification of the first potent GABA
A
receptor-targeting toxins, to our knowledge, in snake venom, which provides a conceptual example for discovering novel ligands to study this receptor family, both functionally and structurally. Moreover, successful synthetic and recombinant production of these toxins [micrurotoxin1 (MmTX1) and MmTX2] will be valuable to further enhance their subtype selectivity or potency. In a broader context, both toxins may provide tools to evoke seizures in assays geared toward testing antiepileptic drugs or as lead molecules for designing therapeutics that modulate GABA
A
receptor activity.
Ongoing unraveling of a continental fauna: Decline and extinction of Australian mammals since European settlement
Authors: Woinarski John C. Z. , Burbidge Andrew A. , Harrison Peter L.
Published: February 2015

Significance

The island continent of Australia harbors much of the world’s most distinctive biodiversity, but this review describes an extent of recent and ongoing loss of its mammal fauna that is exceptionally high and appreciably greater than previously recognized. The causes of loss are dissimilar to those responsible for most biodiversity decline elsewhere in the world.
Oxalic acid and diacylglycerol 36:3 are cross-species markers of sleep debt
Authors: Weljie Aalim M. , Meerlo Peter , Goel Namni , Sengupta Arjun , Kayser Matthew S. , Abel Ted , Birnbaum Morris J. , Dinges David F. , Sehgal Amita
Published: February 2015

Significance

Reduced sleep duration is a hallmark of modern-day society and is increasingly associated with medical conditions, such as diabetes, obesity, metabolic syndrome, and cardiovascular disease. Here we present data from a rat model and human clinical study of chronic sleep restriction, both revealing that two metabolites in blood, oxalic acid and diacylglycerol 36:3, are quantitatively depleted under sleep-restricted conditions and restored after recovery sleep. Our findings also reveal a significant overall shift in lipid metabolism, with higher levels of phospholipids in both species and evidence of a systemic oxidative environment. This work provides a potential link between the known pathologies of reduced sleep duration and metabolic dysfunction.
FT-like proteins induce transposon silencing in the shoot apex during floral induction in rice
Authors: Tamaki Shojiro , Tsuji Hiroyuki , Matsumoto Ayana , Fujita Akiko , Shimatani Zenpei , Terada Rie , Sakamoto Tomoaki , Kurata Tetsuya , Shimamoto Ko
Published: February 2015

Significance

FLOWERING LOCUS T (FT) acts as a mobile floral activator that is synthesized in leaf and transported to shoot apex. A Rice FT-like protein, Heading date 3a (Hd3a), requires interaction with 14-3-3 proteins and transcription factor FD to induce flowering. We confirm that Hd3a and its interactors, as well as their transcriptional target, coexist in the shoot apex at the appropriate time during floral transition. RNA-sequencing analysis of shoot apices from wild-type and RNA-interference plants for FT-like genes showed that 58% of classified transposable elements are transcribed, and >200 are down-regulated in response to FT-like. Our results indicate a link between reproductive development and transposon behavior in the shoot apical meristem, supporting and extending recent evidence for such a link during gametophyte development.
Structures of the Gβ-CCT and PhLP1–Gβ-CCT complexes reveal a mechanism for G-protein β-subunit folding and Gβγ dimer assembly
Authors: Plimpton Rebecca L. , Cuéllar Jorge , Lai Chun Wan J. , Aoba Takuma , Makaju Aman , Franklin Sarah , Mathis Andrew D. , Prince John T. , Carrascosa José L. , Valpuesta José M. , Willardson Barry M.
Published: February 2015

Significance

G-protein signaling contributes to nearly all aspects of cell physiology. In order for signaling to occur, the G-protein αβγ heterotrimer must be assembled from its individual subunits. The G-protein βγ subcomplex does not assemble spontaneously, but requires the protein-folding chaperone cytosolic chaperonin containing TCP-1 (CCT) and its cochaperone phosducin-like protein 1 (PhLP1). To understand the molecular mechanism underlying this process, we determined the structures of two key intermediates in Gβγ assembly, Gβ-CCT and PhLP1–Gβ-CCT, using cryo-electron microscopy and chemical cross-linking. These structures reveal the molecular basis for chaperone-mediated Gβγ assembly that can be exploited to design novel therapeutics to regulate G-protein signaling.
Elevated intraocular pressure decreases response sensitivity of inner retinal neurons in experimental glaucoma mice
Authors: Pang Ji-Jie , Frankfort Benjamin J. , Gross Ronald L. , Wu Samuel M.
Published: February 2015

Significance

Glaucoma is a leading cause of blindness, associated with elevated intraocular pressure (IOP) and progressive loss of the optic nerve and retinal ganglion cells (RGCs). Glaucoma patients exhibit diffuse loss of visual sensitivity, but the cellular origins of such sensitivity loss is unknown. In this study, we present evidence showing that elevated IOP decreases the efficacy of the rod bipolar cell to the AII amacrine cell synapse, resulting in reduction of RGC sensitivity. These findings, for the first time to our knowledge, identify the synaptic loci mediating visual sensitivity loss in early glaucoma, and can be used to develop new diagnostic tools and treatments for this blinding disease.
Rapid behavioral maturation accelerates failure of stressed honey bee colonies
Authors: Perry Clint J. , Søvik Eirik , Myerscough Mary R. , Barron Andrew B.
Published: February 2015

Significance

Honey bee colony death rates are unsustainably high. While many stressors have been identified that contribute to this problem, we do not know why colonies transition so rapidly from a state of apparent health to failure. It is well known that individual bees react to nutritional and pathogen stresses by foraging precociously: our study explains how colony failure arises from the social responses of individual bees to stress. We used radio tracking to monitor performance of bees and found that workers who begin foraging prematurely perform very poorly. This compounds the stresses on the colony and accelerates failure. We suggest how colonies at risk can be identified early, and the most effective interventions to prevent failure.
Probing equilibrium glass flow up to exapoise viscosities
Authors: Pogna Eva Arianna Aurelia , Rodríguez-Tinoco Cristian , Cerullo Giulio , Ferrante Carino , Rodríguez-Viejo Javier , Scopigno Tullio
Published: February 2015

Significance

“Does the glass cease to flow at some finite temperature?” Answering this question––of pivotal importance for glass formation theories––would require ridiculously long observation times. We circumvent this infeasibility relating the (directly inaccessible) ultraviscous flow of a liquid to the elastic properties of the corresponding glass, which we measure as a function of its age. The older the glass, the lower the temperature at which viscosity can be determined. Taking advantage of physical vapor deposition, we rapidly obtain a wide spectrum of ages rivaling those of millenary ambers, enabling viscosity determinations at values as large as those pertaining to the asthenosphere. Our result ultimately rules out the finite-temperature divergence of the molecular diffusion timescale in a glass.
Low expression of CD39 on regulatory T cells as a biomarker for resistance to methotrexate therapy in rheumatoid arthritis
Authors: Peres Raphael Sanches , Liew Foo Y. , Talbot Jhimmy , Carregaro Vanessa , Oliveira Rene D. , Almeida Sergio L. , França Rafael F. O. , Donate Paula B. , Pinto Larissa G. , Ferreira Flavia I. S. , Costa Diego L. , Demarque Daniel P. , Gouvea Dayana Rubio , Lopes Norberto P. , Queiroz Regina Helena C. , Silva Joao Santana , Figueiredo Florencio , Alves-Filho Jose Carlos , Cunha Thiago M. , Ferreira Sérgio H. , Louzada-Junior Paulo , Cunha Fernando Q.
Published: February 2015

Significance

Methotrexate (MTX) is the first-line therapy for rheumatoid arthritis (RA). However, about 40% of patients are resistant to MTX. Furthermore, MTX resistance is only apparent after a prolonged continuous MTX treatment (>3 mo), by which time the disease of the nonresponders would have aggravated. Thus, there is a considerable unmet need for a biomarker to select MTX-resistant patients and place them immediately on alternative therapy. We found here that the low density of CD39 on peripheral regulatory T cells in RA patients is a rapid, convenient, and reliable (
P
< 0.01) biomarker for MTX resistance. Our findings also provide previously unrecognized information on aspects of immune regulation in RA and the mechanism of action of MTX.
Lemon-shaped halo archaeal virus His1 with uniform tail but variable capsid structure
Authors: Hong Chuan , Pietilä Maija K. , Fu Caroline J. , Schmid Michael F. , Bamford Dennis H. , Chiu Wah
Published: February 2015

Significance

Many lemon-shaped double-stranded DNA viruses have been observed to infect archaeal cells in both extreme and moderate environments. We used cryo-electron tomography with subtomogram classification and averaging to reveal the three-dimensional structures of a lemon-shaped haloarchaeal virus, His1. Although the His1 exhibited size and shape heterogeneity, its tail structure was found to be constant. Extensive biochemical studies show that, while extremely stable, under certain conditions the capsid can transform into a tube without the genome. These observations demonstrate that the capsid proteins are able to perform a remarkable surface lattice transformation.
Autism-associated mutation inhibits protein kinase C-mediated neuroligin-4X enhancement of excitatory synapses
Authors: Bemben Michael A. , Nguyen Quynh-Anh , Wang Tongguang , Li Yan , Nicoll Roger A. , Roche Katherine W.
Published: February 2015

Significance

The last decade has delivered astounding advances in DNA sequencing technology, which has led to the wide discovery of point mutations in genes associated with neuropsychiatric disorders. However, the mechanism by which the majority of mutations may contribute to the disease is unknown. Here we show that a reported autism mutation can dramatically inhibit a posttranslational modification, which leads to profound synaptic changes. These data underscore how a simple perturbation of a protein at the synapse can lead to dramatic changes in synaptic transmission and supports a model by which imbalances of excitatory/inhibitory currents may underlie the pathophysiology of autism.
Feedback stabilizes propagation of synchronous spiking in cortical neural networks
Authors: Moldakarimov Samat , Bazhenov Maxim , Sejnowski Terrence J.
Published: February 2015

Significance

Feedback projections are ubiquitous in the brain, but little is known about what they contribute to information processing. The results presented here provide testable hypotheses for the functional role of the feedback projections in the brain. Our work suggests that feedback projections could be responsible for information encoded in spike times to reliably propagate through cortex, and thus could serve as an attentional mechanism to regulate the flow of information in the cortex. Our work also suggests that feedback projections may also be critically involved in organizing neural populations involved in cognitive functions by generating and sharpening spike-time synchronization among populations of neurons. Thus, feedback projections could be key to understanding how the cortex is globally organized.
Response to Davies and Fuchs
Authors: Mukherjee Joybrato
Published: February 2015

Commentary to: Davies, Mark, and Robert Fuchs. 2015. "Expanding horizons in the study of World Englishes with the 1.9 billion word Global Web-based English Corpus (GloWbE)". English World-Wide 36:1–28 (This issue). DOI:10.1075/eww.36.1.01dav
At the interface of contact linguistics and second language acquisition research
Authors: Gilquin Gaëtanelle
Published: February 2015

This paper examines the possible interface between contact linguistics and second language acquisition research by comparing the institutionalized second-language varieties of English known as “New Englishes” and the foreign varieties of English called “Learner Englishes”. On the basis of corpus data representing several populations of various origins, it investigates four linguistic phenomena, ranging from syntax (embedded inversion) to lexis (phrasal verbs withup), through phraseology (word clusters) and pragmatics (discourse markers), with a view to identifying similarities and differences between the two types of varieties at several levels of the language. The paper also explores avenues for going beyond a descriptive account towards a more explanatory one, in an attempt to build the foundations of a theoretical rapprochement between contact linguistics and second language acquisition research.
Hot water extracts of edible Chrysanthemum morifolium Ramat. exert antidiabetic effects in obese diabetic KK-Ay mice
Authors: Yamamoto Junpei , Tadaishi Miki , Yamane Takumi , Oishi Yuichi , Shimizu Makoto , Kobayashi-Hattori Kazuo
Published: February 2015

In this study, the antidiabetic effects of a hot water extract of edible Chrysanthemum morifolium Ramat. (HW-ECM) were investigated in type 2 diabetic mice. HW-ECM improved blood glucose levels and insulin resistance and increased adiponectin mRNA expression in adipose tissues and protein concentrations in the plasma. Moreover, it increased adipose mRNA and protein expressions of peroxisome proliferator-activated receptor γ (PPARγ), a regulator of adiponectin transcription, and mRNA expression of its downstream target genes. It also reduced the adipose cell size and attenuated the mRNA expression of pro-inflammatory adipocytokines in adipose tissues. These data presumably indicate a hypoglycemic mechanism of HW-ECM, involving increased PPARγ expression, decreased the adipocyte sizes, and suppression of chronic inflammation in adipose tissues. Finally, elevated adiponectin levels lead to amelioration of insulin resistance and the corresponding hypoglycemic effects. Therefore, HW-ECM indicates its potential as a functional food for type 2 diabetes.
Changes in the Economic Returns to Attending Prestigious Institutions in Norway
Authors: Borgen Nicolai T.
Published: February 2015

The purpose of this paper is to explore whether the returns to attending a prestigious higher education institution have increased in Norway for students who graduated in 1975 to students who graduated in 1999. A handful of published studies find that the returns to attending prestigious institutions have increased in the last decades. However, they all study the USA, which has a decentralized wage bargaining system. The results in this paper shed light on whether a centralized wage bargaining system, typical for many west-European countries, prevents the returns to attending prestigious institutions from increasing. I find that attending prestigious institutions pays off economically in Norway and that the returns have increased throughout the investigated period. Another aim of this paper is to investigate whether the returns have increased more at the top of the earnings distribution than at the bottom. I find that the returns are highest at the top of the earnings distribution and have increased the most at the top. At the 90th quantile, for instance, students who attended a prestigious business school between 1975 and 1979 obtained 80% higher earnings than students attending nonprestigious institutions in the same period. Among students who graduate 20 years later, this difference is 139%.
Tactical behaviour of winning athletes in major championship 1500‐m and 5000‐m track finals
Authors: Aragón Sonia , Lapresa Daniel , Arana Javier , Anguera M. Teresa , Garzón Belén
Published: February 2015

This article analyses the tactics employed by middle‐distance (1500‐m) and long‐distance (5000‐m) runners from an observational methodology perspective. The subject of investigation has received little attention from specialists in the field of athletics, with most research focusing on physiological studies of athlete performance. Using an ad hoc observation tool and a database containing systematically recorded data we detected time patterns (T‐patterns) within the data recorded using the Theme software program (version 5.0), and analysed the tactics employed by winners of the men's 1500‐m and 5000‐m finals of the World Championships in Athletics [Edmonton 2001, Paris 2003, Helsinki 2005 (1500‐m final only), Osaka 2007 (1500‐m final only), Berlin 2009 and Daegu 2011], the European Athletics Championships (Munich 2002, Göteborg 2006, and Barcelona 2010) and the Olympic Games (Sydney 2000, Athens 2004, Beijing 2008 and London 2012). T‐pattern detection and investigation of the relationship between category systems corresponding to the criteria comprising the observation tool revealed both similarities (starting lane and lane used during race, runner's position during race and sprint zone and lane) and differences (variations in pace, zones in which changes of pace occur, sprint initiation zone and winner's position at the start of the sprint) between the two disciplines.
Rhodopsin kinase and recoverin modulate phosphodiesterase during mouse photoreceptor light adaptation
Authors: Chen Ching-Kang , Woodruff Michael L. , Fain Gordon L.
Published: February 2015

Light stimulates rhodopsin in a retinal rod to activate the G protein transducin, which binds to phosphodiesterase (PDE), relieving PDE inhibition and decreasing guanosine 3′,5′-cyclic monophosphate (cGMP) concentration. The decrease in cGMP closes outer segment channels, producing the rod electrical response. Prolonged exposure to light decreases sensitivity and accelerates response kinetics in a process known as light adaptation, mediated at least in part by a decrease in outer segment Ca2+. Recent evidence indicates that one of the mechanisms of adaptation in mammalian rods is down-regulation of PDE. To investigate the effect of light and a possible role of rhodopsin kinase (G protein–coupled receptor kinase 1 [GRK1]) and the GRK1-regulating protein recoverin on PDE modulation, we used transgenic mice with decreased expression of GTPase-accelerating proteins (GAPs) and, consequently, a less rapid decay of the light response. This slowed decay made the effects of genetic manipulation of GRK1 and recoverin easier to observe and interpret. We monitored the decay of the light response and of light-activated PDE by measuring the exponential response decay time (τREC) and the limiting time constant (τD), the latter of which directly reflects light-activated PDE decay under the conditions of our experiments. We found that, in GAP-underexpressing rods, steady background light decreased both τREC and τD, and the decrease in τD was nearly linear with the decrease in amplitude of the outer segment current. Background light had little effect on τREC or τD if the gene for recoverin was deleted. Moreover, in GAP-underexpressing rods, increased GRK1 expression or deletion of recoverin produced large and highly significant accelerations of τREC and τD. The simplest explanation of our results is that Ca2+-dependent regulation of GRK1 by recoverin modulates the decay of light-activated PDE, and that this modulation is responsible for acceleration of response decay and the increase in temporal resolution of rods in background light.
The Sexual Dimorphism Associated with Pulmonary Hypertension Corresponds to a Fibrotic Phenotype
Authors: Rafikova Olga , Rafikov Ruslan , Meadows Mary Louise , Kangath Archana , Jonigk Danny , Black Stephen M.
Published: February 2015

Although female predominance in the development of all types of pulmonary hypertension (PH) is well established, many clinical studies have confirmed that females have better prognosis and higher survival rate than males. There is no clear explanation of why sex influences the pathogenesis and progression of PH. Using a rat angioproliferative model of PH, which closely resembles the primary pathological changes observed in humans, we evaluated the role of sex in the development and progression of PH. Female rats had a more pronounced increase in medial thickness in the small pulmonary arteries. However, the infiltration of small pulmonary arteries by inflammatory cells was found only in male rats, and this corresponded to increased myeloperoxidase activity and abundant adventitial and medial fibrosis that were not present in female rats. Although the level of right ventricle (RV) peak systolic pressure was similar in both groups, the survival rate in male rats was significantly lower. Moreover, male rats presented with a more pronounced increase in RV thickness that correlated with diffuse RV fibrosis and significantly impaired right cardiac function. The reduction in fibrosis in female rats correlated with increased expression of caveolin‐1 and reduced endothelial nitric oxide synthase–derived superoxide. We conclude that, in the pathogenesis of PH, female sex is associated with greater remodeling of the pulmonary arteries but greater survival. Conversely, in males, the development of pulmonary and cardiac fibrosis leads to early and severe RV failure, and this may be an important reason for the lower survival rate among males.
Effects of in-plane stiffness and charge transfer on thermal expansion of monolayer transition metal dichalcogenide*
Authors: Wang Zhan-Yu , Zhou Yan-Li , Wang Xue-Qing , Wang Fei , Sun Qiang , Guo Zheng-Xiao , Jia Yu
Published: February 2015

The temperature dependence of lattice constants is studied by using first-principles calculations to determine the effects of in-plane stiffness and charge transfer on the thermal expansions of monolayer semiconducting transition metal dichalcogenides. Unlike the corresponding bulk material, our simulations show that monolayer MX
2 (M = Mo and W; X = S, Se, and Te) exhibits a negative thermal expansion at low temperatures, induced by the bending modes. The transition from contraction to expansion at higher temperatures is observed. Interestingly, the thermal expansion can be tailored regularly by alteration of the M or X atom. Detailed analysis shows that the positive thermal expansion coefficient is determined mainly by the in-plane stiffness, which can be expressed by a simple relationship. Essentially the regularity of this change can be attributed to the difference in charge transfer between the different elements. These findings should be applicable to other two-dimensional systems.
Systolic Blood Pressure Control Among Individuals With Type 2 Diabetes: A Comparative Effectiveness Analysis of Three Interventions
Authors: Espeland Mark A. , Probstfield Jeffery , Hire Donald , Redmon J. Bruce , Evans Gregory W. , Coday Mace , Lewis Cora E. , Johnson Karen C. , Wilmoth Sharon , Bahnson Judy , Dulin Michael F. , Green Jennifer B. , Knowler William C. , Kitabchi Abbas , Murillo Anne L. , Osei Kwame , Rehman Shakaib U. , Cushman William C. ,   the Look AHEAD Research Group,   the ACCORD Study Group
Published: February 2015

BACKGROUND

The relative effectiveness of 3 approaches to blood pressure control—(i) an intensive lifestyle intervention (ILI) focused on weight loss, (ii) frequent goal-based monitoring of blood pressure with pharmacological management, and (iii) education and support—has not been established among overweight and obese adults with type 2 diabetes who are appropriate for each intervention.

METHODS

Participants from the Action for Health in Diabetes (Look AHEAD) and the Action to Control Cardiovascular Risk in Diabetes (ACCORD) cohorts who met criteria for both clinical trials were identified. The proportions of these individuals with systolic blood pressure (SBP) <140mm Hg from annual standardized assessments over time were compared with generalized estimating equations.

RESULTS

Across 4 years among 480 Look AHEAD and 1,129 ACCORD participants with baseline SBPs between 130 and 159mm Hg, ILI (OR = 1.46; 95% CI = [1.18–1.81]) and frequent goal-based monitoring with pharmacotherapy (OR = 1.51; 95% CI = [1.16–1.97]) yielded higher rates of blood pressure control compared to education and support. The intensive behavioral-based intervention may have been more effective among individuals with body mass index >30kg/m2, while frequent goal-based monitoring with medication management may be more effective among individuals with lower body mass index (interaction P = 0.047).

CONCLUSIONS

Among overweight and obese adults with type 2 diabetes, both ILI and frequent goal-based monitoring with pharmacological management can be successful strategies for blood pressure control.

CLINICAL TRIALS REGISTRY

clinicaltrials.gov identifiers NCT00017953 (Look AHEAD) and NCT00000620 (ACCORD).
Trade-offs between invertebrate fisheries catches and ecosystem impacts in coastal New Zealand
Authors: Eddy Tyler D. , Coll Marta , Fulton Elizabeth A. , Lotze Heike K.
Published: February 2015

Invertebrate catches are increasing globally following the depletion of many finfish stocks, yet stock assessments and management plans for invertebrates are limited, as is an understanding of the ecosystem effects of these fisheries. Using an ecosystem modelling approach, we explored the trade-offs between invertebrate catches and their impacts on the associated ecosystem on the south coast of Wellington, New Zealand. We simulated exploitation of lobster (Jasus edwardsii), abalone (Haliotis australis, H. iris), and sea urchin (Evechinus chloroticus) over a range of depletion levels—from no depletion to local extinction—to estimate changes in target catches and associated effects on other species groups, trophic levels, and benthic and pelagic components. Exploitation of lobster showed the strongest ecosystem effects, followed by abalone and urchin. In all three fisheries, the current exploitation rate exceeds that which produces maximum sustainable yield, with considerable ecosystem effects. Interestingly, a reduced exploitation rate is predicted to increase target catches (and catch-per-unit-effort), thereby strongly reducing ecosystem effects, a win–win situation. Our results suggest that invertebrate exploitation clearly influences ecosystem structure and function, yet the direction and magnitude of responses depend on the target group and exploitation rate. An ecosystem-based fisheries management approach that includes the role of invertebrates would improve the conservation and management of invertebrate resources and marine ecosystems on broader scales.
Classification of group B streptococci with reduced β-lactam susceptibility (GBS-RBS) based on the amino acid substitutions in PBPs
Authors: Kimura Kouji , Nagano Noriyuki , Arakawa Yoshichika
Published: February 2015

All clinical isolates of group B Streptococcus (GBS; Streptococcus agalactiae) are considered uniformly susceptible to β-lactams, including penicillins. However, GBS with reduced penicillin susceptibility (PRGBS) were first identified by our group in Japan and have also been reported from North America. PRGBS are non-susceptible to penicillin because of acquisition of amino acid substitutions near the conserved active-site motifs in PBP2X. In particular, V405A and Q557E are considered the key amino acid substitutions responsible for penicillin non-susceptibility. We revealed that in addition to the substitutions in PBP2X, an amino acid substitution in PBP1A confers high-level cephalosporin resistance in GBS. As the number of publications on GBS with reduced β-lactam susceptibility (GBS-RBS), especially PRGBS, and concomitantly the need for a systematic classification of GBS-RBS is increasing, we propose here a classification of GBS-RBS based on the amino acid substitutions in their PBPs.
Comparative outcome studies of clinical decision support software: limitations to the practice of evidence-based system acquisition
Authors: Dhiman Gaurav Jay , Amber Kyle T , Goodman Kenneth W.
Published: February 2015

Clinical decision support systems (CDSSs) assist clinicians with patient diagnosis and treatment. However, inadequate attention has been paid to the process of selecting and buying systems. The diversity of CDSSs, coupled with research obstacles, marketplace limitations, and legal impediments, has thwarted comparative outcome studies and reduced the availability of reliable information and advice for purchasers. We review these limitations and recommend several comparative studies, which were conducted in phases; studies conducted in phases and focused on limited outcomes of safety, efficacy, and implementation in varied clinical settings. Additionally, we recommend the increased availability of guidance tools to assist purchasers with evidence-based purchases. Transparency is necessary in purchasers’ reporting of system defects and vendors’ disclosure of marketing conflicts of interest to support methodologically sound studies. Taken together, these measures can foster the evolution of evidence-based tools that, in turn, will enable and empower system purchasers to make wise choices and improve the care of patients.
The discovery of the periodic table as a case of simultaneous discovery
Authors: Scerri Eric
Published: February 2015

The article examines the question of priority and simultaneous discovery in the context of the discovery of the periodic system. It is argued that rather than being anomalous, simultaneous discovery is the rule. Moreover, I argue that the discovery of the periodic system by at least six authors in over a period of 7 years represents one of the best examples of a multiple discovery. This notion is supported by a new view of the evolutionary development of science through a mechanism that is dubbed Sci-Gaia by analogy with Lovelock's Gaia hypothesis.
Third row transition metals for the treatment of cancer
Authors: Johnstone Timothy C. , Suntharalingam Kogularamanan , Lippard Stephen J.
Published: February 2015

Platinum compounds are a mainstay of cancer chemotherapy, with over 50% of patients receiving platinum. But there is a great need for improvement. Major features of the cisplatin mechanism of action involve cancer cell entry, formation mainly of intrastrand cross-links that bend and unwind nuclear DNA, transcription inhibition and induction of cell-death programmes while evading repair. Recently, we discovered that platinum cross-link formation is not essential for activity. Monofunctional Pt compounds such as phenanthriplatin, which make only a single bond to DNA nucleobases, can be far more active and effective against a range of tumour types. Without a cross-link-induced bend, monofunctional complexes can be accommodated in the major groove of DNA. Their biological mechanism of action is similar to that of cisplatin. These discoveries opened the door to a large family of heavy metal-based drug candidates, including those of Os and Re, as will be described.
The periodic table: icon and inspiration
Authors: Poliakoff Martyn , Tang Samantha
Published: February 2015

To start this discussion meeting on the new chemistry of the elements held on 12 May 2014, Martyn Poliakoff, Foreign Secretary of the Royal Society, was invited to give the opening remarks. As a chemist and a presenter of the popular online video channel ‘The periodic table of videos’, Martyn communicates his personal and professional interest in the elements to the public, who in turn use these videos both as an educational resource and for entertainment purposes. Ever since Mendeleev’s first ideas for the periodic table were published in 1869, the table has continued to grow as new elements have been discovered, and it serves as both icon and inspiration; its form is now so well established that it is recognized the world over as a symbol for science. This paper highlights but a few of the varied forms that the table can take, such as an infographic, which can convey the shortage of certain elements with great impact.