bluuebunny/crossref_metadata_2025 huggingface dataset:
Amplitude modulation of all three velocity components in turbulent boundary layers
Authors: Talluru K. M. , Baidya R. , Hutchins N. , Marusic I.
Published: March 2014

A combination of cross-wire probes with an array of flush-mounted skin-friction sensors are used to study the three-dimensional conditional organisation of large-scale structures in a high-Reynolds-number turbulent boundary layer. Previous studies have documented the amplitude modulation of small-scale motions in response to conditionally averaged large-scale events, but the data are largely restricted to the streamwise component of velocity alone. Here, we report results based on all three components of velocity and find that the small-scale spanwise and wall-normal fluctuations ($v$ and $w$) and the instantaneous Reynolds shear stress ($-{uw}$) are modulated in a very similar manner to that previously noted for the streamwise fluctuations ($u$). The envelope of the small scale fluctuations for all velocity components is well described by the large-scale component of the $u$ fluctuation. These results also confirm the conditional existence of roll modes associated with the very large-scale or ‘superstructure’ motions.
Richness and diversity of helminth species in eels from a hypersaline coastal lagoon, Mar Menor, south-east Spain
Authors: Mayo-Hernández E. , Peñalver J. , García-Ayala A. , Serrano E. , Muñoz P. , Ruiz de Ybáñez R.
Published: March 2014

The composition and diversity of parasite communities and intestinal components, as well as infra-community structure, were assessed in eelsAnguilla anguilla,from Mar Menor, a permanent Mediterranean hypersaline coastal lagoon. Data were used to determine whether this helminth community differs in composition and structure from that of eels in lagoons with lower salinity regimes and higher freshwater inputs. A total prevalence of 93% was detected. Specifically, parasites were identified asDeropristis inflata,Bucephalus anguillae,Contracaecumsp.,Anguillicoloides crassusand two plerocercoid larvae belonging to the order Proteocephalidae, the marine species representing 91% of the isolated helminths. In the total community, digenetic trematodes were the dominant group of helminths, andD. inflata, an eel specialist, dominated both the component community and the infra-community. Richness and diversity were low but similar to those reported in other saline lagoons, and maximum species per eel did not exceed four. At the infra-community level, higher abundance than in other brackish or marine Mediterranean environments was detected. The findings provide further evidence of the similarity in composition and structure of helminth communities in eels from various Mediterranean coastal lagoons. Moreover, salinity-dependent specificities are well supported and reflect the life history of individual eels.
Differential Influence of 5-HTTLPR - Polymorphism and COMT Val158Met - Polymorphism on Emotion Perception and Regulation in Healthy Women
Authors: Weiss Elisabeth M. , Freudenthaler H. Harald , Fink Andreas , Reiser Eva M. , Niederstätter Harald , Nagl Simone , Parson Walther , Papousek Ilona
Published: March 2014

Converging evidence indicates that a considerable amount of variance in self-estimated emotional competency can be directly attributed to genetic factors. The current study examined the associations between the polymorphisms of the Catechol-O-methyltransferase (COMT Met158Val) and the serotonin transporter (5-HTTLPR) and specific measures of the self-estimated effectiveness of an individual’s emotion perception and regulation. Emotional competence was measured in a large sample of 289 healthy women by using the Self-report Emotional Ability Scale (SEAS), which includes two subscales for the assessment of emotion perception and regulation in the intra-personal domain and two subscales for the assessment of emotion perception and regulation in the inter-personal domain. Participants’ reports of effective emotion regulation in everyday life were associated with the COMT Met-allele, with women homozygous for the Val-allele scoring lowest on this scale. Self-estimated effectiveness of emotion perception of the individual’s own emotions was related to the 5-HTTLPR. Both homozygous groups (s/s and l/l) rated their intra-personal emotion perception less effective than participants in the heterozygous s/l group. Taken together, the results indicate that genetic variants of the COMT and 5HTTLPR genes are differentially associated with specific measures of the self-estimated effectiveness of an individual’s emotion perception and regulation in the intra-personal domain. (JINS, 2014, 20, 1–9)
Impact of vitamin D supplementation on health-care use in a 25-hydroxyvitamin D-tested population in France: a population-based descriptive cohort study
Authors: Caillet Pascal , Jaglal Susan B , Laforest Laurent , Chapurlat Roland , Rabilloud Muriel , Ducher Michel , Schott Anne-Marie
Published: March 2014

Objective

Chronic vitamin D deficiency has been associated in some patients with diffuse musculoskeletal pain. These unspecific symptoms may partly explain why vitamin D deficiency is often diagnosed late. Our aim was to analyse health-care claims after vitamin D supplementation in patients likely to have vitamin D deficiency.

Design

Ambulatory health-care claims were compared before and after a vitamin D supplementation prescribed following a 25-hydroxyvitamin D assay.

Setting

Health Insurance Fund (FHIF) database of the Rhône-Alpes area, France.

Subjects

Among patients reimbursed for a 25-hydroxyvitamin D assay between 1 December 2008 and 31 January 2009, those supplemented with vitamin D after the assay were matched on the date of assay to patients who did not receive vitamin D.

Results

Among the 3023 patients who had a 25-hydroxyvitamin D assay, 935 were consequently supplemented and matched to 935 patients not supplemented. Their median age was 50·0 and 49·5 years, respectively. Patients supplemented decreased their muscle relaxant consumption whereas no change was observed in the reference group, the difference between the two groups was significant (P=0·03). Second and third Pain Relief Ladder prescriptions decreased in both groups but not significantly differently between groups (P=0·58). There was a decrease in prescriptions of biological examination in both groups with no significant difference.

Conclusions

Besides a decrease in muscle relaxant prescriptions in the supplemented group, it was difficult to assess the impact of vitamin D supplementation in patients likely to have vitamin D deficiency. Prospective cohort studies and randomized trials are needed to assess the efficiency of screening and supplementing vitamin D deficiency.
Construction of Wife and Mother Identities in Women’s Talk of Intrafamily Violence in Saraycık-Turkey
Authors: Güvenç Gülden
Published: March 2014

The present study explored how Turkish women in squatter communities on the fringes of an urban center positioned themselves in talk about family violence. Women’s talk revealed their interpretative repertoires with respect to intrafamily violence and power relations, how they constructed identities as wives and mothers, and how they envisioned alternative, more egalitarian social relations. Three focus groups, each comprising 10 women from Saraycık, a poor neighborhood of Ankara, met for an hour once every week for a period of 9 weeks. Six questions about intrafamily violence provoked conversations about power relations and violence with their children and husbands. Transcriptions of these conversations were analyzed for manifest content, latent content, interpretative repertoires, and the functions served by the interpretative repertoires. On the basis of the categorization, I identified the complexity of women’s positions, particularly with respect to their children as both the central meaning of life and children as getting on women’s nerves. Many interpretations placed blame on a member of the family—the woman herself, her children, or husband. Some women envisioned an alternative future that would be achieved through education, employment, and the exercise of agency. The findings imply that the constructed wife and mother identities of Turkish women in the economically vulnerable urban squatter settlements include tension and complex experiences that are in flux as the women imagine other possibilities.
Engineering cyanobacteria for the production of a cyclic hydrocarbon fuel from CO2and H2O
Authors: Halfmann Charles , Gu Liping , Zhou Ruanbao
Published: March 2014

Engineering the filamentous, N2-fixing cyanobacteria as a cellular factory to produce and secrete a cyclic hydrocarbon fuel using atmospheric gases (CO2and N2), water, and sunlight.
Polymeric micelles as drug delivery vehicles
Authors: Ahmad Zaheer , Shah Afzal , Siddiq Muhammad , Kraatz Heinz-Bernhard
Published: March 2014

Though much progress has been made in drug delivery systems, the design of a suitable carrier for the delivery of hydrophobic drugs is still a major challenge for researchers.
Flexible Cu2ZnSnS4 solar cells based on successive ionic layer adsorption and reaction method
Authors: Sun Kaiwen , Su Zhenghua , Yan Chang , Liu Fangyang , Cui Hongtao , Jiang Liangxing , Shen Yansong , Hao Xiaojing , Liu Yexiang
Published: March 2014

Using a commercially viable and environmentally friendly aqueous chemical method, Cu2ZnSnS4 films with different stacked structure precursors are prepared on flexible Mo foil substrates, and then solar cells with the structure of Ag/AZO/i-ZnO/CdS/CZTS/Mo foil are fabricated.
A DNA–scaffolded silver nanocluster/Cu2+ ensemble as a turn-on fluorescent probe for histidine
Authors: Zhou Ying , Zhou Tianshu , Zhang Min , Shi Guoyue
Published: March 2014

A new type of rapid, sensitive, and selective fluorescence turn-on assay was developed for detection of histidine using a DNA–scaffolded silver nanocluster/Cu2+ ensemble (DNA–AgNC/Cu2+).
Investigation of the facet-dependent performance of α-Fe2O3 nanocrystals for heavy metal determination by stripping voltammetry
Authors: Xu Wei-Hong , Meng Qiang-Qiang , Gao Chao , Wang Jing , Li Qun-Xiang , Liu Jin-Huai , Huang Xing-Jiu
Published: March 2014

The electrochemical performances of α-Fe2O3 nanocubes, nanoplates, and nanorods modified GCEs toward Pb2+ detection strongly depend on their exposed facets.
Site-specific cross-linking of collagen peptides by lysyl advanced glycation endproducts
Authors: Kamalov M. , Harris P. W. R. , Cooper G. J. S. , Brimble M. A.
Published: March 2014

Cross-linking lysyl AGEs were synthesised and incorporated into two types of collagen peptides and now enable detailed analysis of the effects these cross-links have on biological systems.
Development of a transverse thermoelectric voltage effect in artificial SrTiO3/SrTi1−xNbxO3 epitaxial multilayer films with incline-oriented sublayers
Authors: Qin Yi , Zhao Ting , Wang Bo , Zhang Pengxiang , Yang Jianfeng
Published: March 2014

The TTE voltage effect was greatly improved by constructing the artificial multilayer structure of STO/NSTO with accurate inclined orientation.
In situ precipitation of amorphous and crystalline calcium sulphates in cellulose thin films
Authors: Nissinen Tomi , Li Mei , Davis Sean A. , Mann Stephen
Published: March 2014

Cellulose films regenerated with calcium sulphate are fabricated using N-methylmorpholine N-oxide as a solvent and capping agent for polysaccharide dissolution and nanoparticle stabilization, respectively.
A molecular porous zirconium–organic material exhibiting highly selective CO2 adsorption, high thermal stability, reversible hydration, facile ligand exchange and exclusive dimerization of phenylacetylene
Authors: Lee Nam Hee , Lee Dong Woo , Yeo Hakmin , Kwak Kyungwon , Chun Hyang Sook , Ok Kang Min
Published: March 2014

A multi-functional molecular porous zirconium-organic material, CAUMOF-12, has been discovered.
Viscosity scaling of the self-diffusion and velocity cross-correlation coefficients of two functionalised ionic liquids and of their non-functionalized analogues
Authors: Harris Kenneth R. , Makino Takashi , Kanakubo Mitsuhiro
Published: March 2014

Functionalised and unfunctionalised ammonium based ionic liquid analogues show a common Stokes–Einstein–Sutherland scaling with viscosity.
Heat and mass transfer through interfaces of nanosized bubbles/droplets: the influence of interface curvature
Authors: Wilhelmsen Øivind , Bedeaux Dick , Kjelstrup Signe
Published: March 2014

Heat and mass transfer through interfaces is central in nucleation theory, nanotechnology and many other fields of research.
Benzene⋯acetylene: a structural investigation of the prototypical CH⋯π interaction
Authors: Ulrich Nathan W. , Seifert Nathan A. , Dorris Rachel E. , Peebles Rebecca A. , Pate Brooks H. , Peebles Sean A.
Published: March 2014

The benzene⋯acetylene dimer is a symmetric top with μ = 0.438(11) D and H⋯π = 2.4921(1) Å.
On the faradaic selectivity and the role of surface inhomogeneity during the chlorine evolution reaction on ternary Ti–Ru–Ir mixed metal oxide electrocatalysts
Authors: Zeradjanin Aleksandar R. , Menzel Nadine , Schuhmann Wolfgang , Strasser Peter
Published: March 2014

Faradaic selectivity of the chlorine and oxygen evolution (left) is linked to the spatial inhomogeneity of the surface reactivity of Ti–Ru–Ir mixed metal oxide catalysts.
Fluorescent push–pull pH-responsive probes for ratiometric detection of intracellular pH
Authors: Ipuy Martin , Billon Cyrielle , Micouin Guillaume , Samarut Jacques , Andraud Chantal , Bretonnière Yann
Published: March 2014

Fluorophores displaying a sensitive response to pH are reported. Structural variations allow fine tuning of pKa and ratiometric intracellular pH imaging.
Core–shell ZnSe–CdSe quantum dots: a facile approach via decomposition of cyclohexeno-1,2,3-selenadiazole
Authors: Bhanoth Sreenu , More Priyesh V. , Jadhav Aditi , Khanna Pawan K.
Published: March 2014

For the first time ever cyclohexeno-1,2,3-selenadiazole (SDZ) has been employed for the synthesis of core–shell ZnSe–CdSe quantum dots thus promoting an eco-friendly and reasonably less toxic synthesis method for such quantum dot hetero-structures.
Fabrication, modification, and biomedical applications of anodized TiO2nanotube arrays
Authors: Huo Kaifu , Gao Biao , Fu Jijiang , Zhao Lingzhou , Chu Paul K.
Published: March 2014

Recent research activities on the surface modification and biomedical applications of TiO2NTAs are reviewed.
Denser fluids of charge-stabilized colloids form denser sediments
Authors: Nanikashvili Pilkhaz M. , Butenko Alexander V. , Liber Shir R. , Zitoun David , Sloutskin Eli
Published: March 2014

We employ simple fluids of charge-stabilized colloidal spheres to form granular packings under an elevated gravity, establishing links between thermodynamics and granular matter physics.
Effective recovery of acids from iron-based electrolytes using graphene oxide membrane filters
Authors: Sun Pengzhan , Wang Kunlin , Wei Jinquan , Zhong Minlin , Wu Dehai , Zhu Hongwei
Published: March 2014

Efficient recovery of acids from iron-based electrolytes using GO membranes was demonstrated. The trans-membrane transport of H+ was two orders of magnitude greater than that of Fe3+. The circular penetration of iron-based electrolytes could produce acids with high purity, which was superior to other traditional diffusion dialysis processes conducted by polymer-based anion-exchange membranes.
Establishment and biological characterization of a dermal mesenchymal stem cells line from bovine
Authors: Sun Tingting , Yu Chao , Gao Yuhua , Zhao Chenqiong , Hua Jinlian , Cai Lianshun , Guan Weijun , Ma Yuehui
Published: March 2014

The DMSCs (dermal mesenchymal stem cells) are multipotent stem cells, which can differentiate in vitro into many cell types. Much work has been done on DMSCs from humans, mice, rabbits and other mammals, but the related literature has not been published about these cells in cattle. In this study, we isolated and established the DMSC lines from cattle, thereby initiating further research on these cells, such as growth kinetics, detection of special surface antigen and RT–PCR (reverse transcription–PCR) assays to identify the biological characterization of the cell line. Furthermore, the DMSCs are induced to differentiate into adipocytes, osteoblasts and neural cells in vitro. Our results suggest that DMSCs isolated from cattle possess similar biological characteristics with those from other species. Their multi-lineage differentiation capabilities herald a probable application model in tissue engineering and induced pluripotent stem cells.
L’appréciation de la beauté : revue de littérature
Authors: Faure Jacques , Bolender Yves
Published: March 2014

Le jugement esthétique est bien sûr subjectif, mais ceci n’exclut pas une étude rigoureuse mettant en jeu des méthodes scientifiques. La base factuelle de la «science de l’esthétique» ne doit pas établir qu’une personne ou une image est «objectivement» belle, mais elle doit plutôt déterminer comment un groupe social représentatif ou des jurys ressentent cet «objet esthétique» comme beau ou laid. Le but de cet article est la revue des aspects définitionnels, théoriques et méthodologiques de la perception par un groupe social homogène et représentatif, du caractère attractif d’un visage ou d’un sourire. La première partie pose les principes de l’attirance faciale : la perception suppose un jury, un champ d’investigation, et un test susceptible de produire des données quantifiées; les déterminants généraux de la beauté sont ensuite passés en revue : la morphologie moyenne, le background culturel du juge, la numérologie, l’origine ethnique du juge. Les déterminants indirects qui peuvent intervenir sont la denture, l’architecture osseuse et l’enveloppe musculaire. Des facteurs perturbateurs altérant le jugement peuvent être mis en cause; ce sont des facteurs périphériques comme la coiffure et la couleur des cheveux, la texture de la peau, les rides, le rouge à lèvres... ou des facteurs psycho-sociaux comme l’aura du sujet évalué, son intelligence, son comportement. La seconde partie traite de la méthodologie employée pour apprécier «l’attractivité» d’une face et la corréler avec telle ou telle morphologie. Classiquement ceci est réalisé en déterminant la préférence esthétique moyenne pour divers groupes d’images faciales au sein d’un jury qui a pour tache spécifique d’estimer leurs qualités esthétiques. L’échantillon à juger, la présentation des documents, le ou les jurys, la procédure de notation sont discutés; ils doivent être précisés avant de commencer la collecte des données. Une attention spécifique est enfin portée sur la démarche d’appréciation associée à telle ou telle morphologie, décrite par des méthodes morpho-métriques. L’objectif ultime est bien sûr la sélection des morphologies les plus attractives pour nos patients.
Finitions, stabilité et harmonie
Authors: Fourquet Lucile , Göttle Magalie , Bounoure Guy
Published: March 2014

La phase de finition, dernière étape du traitement orthodontique actif, permet de
parfaire l’occlusion, en respectant les critères définis par les différents auteurs et
d’améliorer le résultat esthétique, jusqu’à atteindre les objectifs préalablement fixés.
La pérennité des résultats de fin de traitement ne peut être assurée sans une analyse
initiale et personnalisée des facteurs de risque de récidive propres à chaque patient.
C’est à partir de cette étude que l’orthodontiste va pouvoir chercher à répondre aux
critères de stabilité communs à tout traitement, et choisir individuellement quels
procédés stabilisants employer. La recherche de cette stabilité permettra aux patients
orthodontiques d’accéder à une harmonie durable. Ce cheminement est le processus
inévitable pour lui garantir un équilibre et une harmonie. Huit types d’harmonies, souvent
déjà décrits dans la littérature, sont ici exposés et analysés.
Excellent electrode material of carbon nanotube macro-fibers for electric arc generator
Authors: Ping Wu Zi , Bo Zhang Wei , Zhao Mang , Hong Yin Yan , Yan Hu Ying , Sheng Li Ye , Gao Yang Jian , Feng Xu Qian
Published: March 2014

Macroscopic carbon nanotube (CNT) fibers approximately 1 mm in diameter and 6 m long were prepared from CNT socks. The as-prepared macro-fiber exhibited excellent flexibility and manipulability. Microscopic examination showed that the fibers mainly consisted of CNTs with a fine graphitic structure and a large diameter (approximately 4.6 nm to 6.3 nm). Electric arcs were generated when the macro-fiber came in contact with a metallic electrode at a voltage as low as 30 V. These arcs had high intensity, and the generated temperature was sufficiently high such that the metallic anode electrode (stannum or copper wire) easily melted. CNT crystallinity was only slightly damaged after the electric circuit was discharged. The high intensity of the generated electric arcs suggested the potential applications of the macro-fiber in welding, melting metals, or other related fields.
The changes on physical characteristics of lightning discharge plasma during individual return stroke process
Authors: Xu He , Yuan Ping , Cen Jian-Yong , Zhang Guang-Shu
Published: March 2014

A cloud-to-ground lightning with six return strokes has been recorded with a slit-less spectrograph in Qinghai province. According to the spectra of return strokes without continuous current, the electron density, the channel temperature, and the gas pressure have been calculated. Then, the correlativity of these parameters has been analyzed. The results indicate that the total intensity of spectra is positive correlated to the intensity of spectral line, they both decrease with time rapidly; furthermore, the channel temperature and the gas pressure decrease with time slowly in the similar trends.
The roles of non-extensivity and dust concentration as bifurcation parameters in dust-ion acoustic traveling waves in magnetized dusty plasma
Authors: Narayan Ghosh Uday , Kumar Mandal Pankaj , Chatterjee Prasanta
Published: March 2014

Dust ion-acoustic traveling waves are studied in a magnetized dusty plasma in presence of static dust and non-extensive distributed electrons in the framework of Zakharov-Kuznesstov-Burgers (ZKB) equation. System of coupled nonlinear ordinary differential equations is derived from ZKB equation, and equilibrium points are obtained. Nonlinear wave phenomena are studied numerically using fourth order Runge-Kutta method. The change from unstable to stable solution and consequently to asymptotic stable of dust ion acoustic traveling waves is studied through dynamical system approach. It is found that some dramatical features emerge when the non-extensive parameter and the dust concentration parameters are varied. Behavior of the solution of the system changes from unstable to stable and stable to asymptotic stable depending on the value of the non-extensive parameter. It is also observed that when the dust concentration is increased the solution pattern is changed from oscillatory shocks to periodic solution. Thus, non-extensive and dust concentration parameters play crucial roles in determining the nature of the stability behavior of the system. Thus, the non-extensive parameter and the dust concentration parameters can be treated as bifurcation parameters.
Precision control of thermal transport in cryogenic single-crystal silicon devices
Authors: Rostem K. , Chuss D. T. , Colazo F. A. , Crowe E. J. , Denis K. L. , Lourie N. P. , Moseley S. H. , Stevenson T. R. , Wollack E. J.
Published: March 2014

We report on the diffusive-ballistic thermal conductance of multi-moded single-crystal silicon beams measured below 1 K. It is shown that the phonon mean-free-path ℓ is a strong function of the surface roughness characteristics of the beams. This effect is enhanced in diffuse beams with lengths much larger than ℓ, even when the surface is fairly smooth, 5–10 nm rms, and the peak thermal wavelength is 0.6 μm. Resonant phonon scattering has been observed in beams with a pitted surface morphology and characteristic pit depth of 30 nm. Hence, if the surface roughness is not adequately controlled, the thermal conductance can vary significantly for diffuse beams fabricated across a wafer. In contrast, when the beam length is of order ℓ, the conductance is dominated by ballistic transport and is effectively set by the beam cross-sectional area. We have demonstrated a uniformity of ±8% in fractional deviation for ballistic beams, and this deviation is largely set by the thermal conductance of diffuse beams that support the micro-electro-mechanical device and electrical leads. In addition, we have found no evidence for excess specific heat in single-crystal silicon membranes. This allows for the precise control of the device heat capacity with normal metal films. We discuss the results in the context of the design and fabrication of large-format arrays of far-infrared and millimeter wavelength cryogenic detectors.
Structural phase transitions of robust insulating Bi1-xLaxFe1-yTiyO3 multiferroics
Authors: Zhang Linlin , Yu Jian , Itoh Mitsuru
Published: March 2014

In contrast to leaky BiFeO3, of which two structural phase transitions of cycloidal modulated antiferromagnetic-paramagnetic and ferroelectric-paraelectric are observed below 850 °C, chemical co-substitution to form Bi1−xLaxFe1−yTiyO3 ternary solid solution makes these multiferroic ceramics become robust insulating low dielectric loss and exhibit rich structural phase transitions. Differential thermal analysis and temperature-dependent X-ray diffraction measurements probe four first-order structural phase transitions, e.g., TH = 305 °C, TN = 365 °C, TC = 810 °C, and TS = 830 °C observed in the Bi0.98La0.02Fe0.99Ti0.01O3 system, which are reasonably attributed to Brazovskii-type cycloidal modulated antiferromagnetic-helimagnetic (at TH) and helimagnetic-paramagnetic (at TN) magnetic phase transitions, ferroelectric-paraelectric (at TC) and rhombohedral-cubic (at TS) structural phase transitions, respectively. Magnetic phase transition temperatures change a little but ferroelectric and lattice structural phase transition temperatures decrease gradually with increasing co-substitution up to composition-induced rhombohedral-(pseudo-)cubic structural phase boundary. The first-order nature of magnetic phase transition and emergence of helimagnetic phase were attributed to Ti3+ d1 magnetic disorder distribution in the Fe3+ d5-O-Fe3+ d5 chains, while the first-order nature becomes weak with increasing co-substitution, owing to decreased ferroelectric rhombohedral lattice distortion. An intermediate rhombohedral paraelectric phase is discovered intervening between ferroelectric rhombohedral and paraelectric cubic phase, of which the temperature range defined by difference between TC and TS increases with increasing co-substitution. It was found that TC and TS are able to be predicted quantitatively by reduced mass of unit cell. These findings enrich our understanding of ferroic phase transitions and advance designing novel high temperature multiferroic compounds.
Hanle measurements of electrodeposited Fe/GaAs spin tunnel contacts
Authors: Majumder Sarmita , Hohertz Donna , McNeil James , SpringThorpe Anthony , Kavanagh Karen L.
Published: March 2014

We report spin transport in electrodeposited Fe/n-GaAs tunnel diodes via three-terminal Hanle measurements. For temperatures between 20 K and 150 K, the spin resistance was up to 20 times higher than expected from theoretical calculations and 1000 times larger compared to a vacuum-deposited counterpart. This higher spin resistance was correlated with a higher contact resistance, and a higher concentration of oxygen impurities in the electrodeposited Fe film and interface, as detected via x-ray photoelectron and Auger spectroscopies, and inferred from Fe film nucleation rates. These results can be explained via a small effective tunnel-contact area of 5%, but extra spin filtering via interfacial states or magnetic oxide layers cannot be ruled out. The spin diffusion times (8.5 ± 0.4 ns to 1.8 ± 0.4 ns, for 20 K to 150 K) extracted from Lorentzian fits were in good agreement with values obtained from earlier 4-terminal Hanle measurements (7.8 ± 0.4 ns to 3.2 ± 0.4 ns, for 25 K to 77 K), both 10 times slower than reported vacuum-deposited contacts.
Atomistic simulation of surface functionalization on the interfacial properties of graphene-polymer nanocomposites
Authors: Wang M. C. , Lai Z. B. , Galpaya D. , Yan C. , Hu N. , Zhou L. M.
Published: March 2014

Graphene has been increasingly used as nano sized fillers to create a broad range of nanocomposites with exceptional properties. The interfaces between fillers and matrix play a critical role in dictating the overall performance of a composite. However, the load transfer mechanism along graphene-polymer interface has not been well understood. In this study, we conducted molecular dynamics simulations to investigate the influence of surface functionalization and layer length on the interfacial load transfer in graphene-polymer nanocomposites. The simulation results show that oxygen-functionalized graphene leads to larger interfacial shear force than hydrogen-functionalized and pristine ones during pull-out process. The increase of oxygen coverage and layer length enhances interfacial shear force. Further increase of oxygen coverage to about 7% leads to a saturated interfacial shear force. A model was also established to demonstrate that the mechanism of interfacial load transfer consists of two contributing parts, including the formation of new surface and relative sliding along the interface. These results are believed to be useful in development of new graphene-based nanocomposites with better interfacial properties.
CO2 Pressure Shift and Broadening of Water Lines Near 790 nm
Authors: Lu Yan , Li Xin-fei , Liu An-wen , Hu Shui-ming
Published: March 2014

Carbon dioxide pressure-broadened ro-vibrational transitions belonging to the v2+3v3 band of H216O have been measured with a sensitive cavity ring-down spectrometer. Water vapor of relatively low pressures (<0.5 Torr) was used to limit the self-collisions among water molecules. After the calibration using the precise atomic transitions of Rb and a thermostabilized Fabry-Pérot interferometer, 10−5 cm−1 frequency accuracy has been achieved. Line parameters are derived from least-squares fitting of the spectra using the “soft” collision model. The retrieved line parameters can be applied in the study of water absorption in the CO2-rich atmospheres of planets like Venus and Mars.
Interaction Study between DNA and Histone Proteins on Single-molecule Level using Atomic Force Microscopy
Authors: Liu Yu-ying , Wang Peng-ye , Dou Shuo-xing , Lv Hong-feng
Published: March 2014

DNA and histone protein are important in the formation of nucleosomal arrays, which are the first packaging level of DNA into a more compact chromatin structure. To characterize the interactions of DNA and histone proteins, we reconstitute nucleosomes using lambda DNA and whole histone proteins by dialysis and perform direct atomic force microscopy (AFM) imaging. Compared with non-specific DNA and histone binding, nucleosomes are formed within the assembled “beads-on-a-string” nucleosomal array by dialysis. These observations facilitate the establishment of the molecular mechanisms of nucleosome and demonstrate the capability of AFM for protein-DNA interaction analysis.
New Hexagonal-rhombic Trilayer Ice Structure Confined between Hydrophobic Plates
Authors: Jia Min , Zhao Wen-hui , Yuan Lan-feng
Published: March 2014

We perform molecular dynamics simulations for water confined between two smooth hydrophobic walls and observe two crystalline structures with one being first reported. Both of these structures obey the ice rule. The novel ice phase is a flat hexagonal-rhombic trilayer ice, obtained under 1 GPa load at wall separation of 1.0 nm. In this structure, the water molecules in the two layers next to one of the walls (outer layers) and in the middle layer form hexagonal rings and rhombic rings, respectively. For a molecule in the outer layers, three of its four hydrogen bonds are in the same layer, and the other one hydrogen bond connects to the middle layer. For a molecule in the middle layer, only two of its four hydrogen-bonds are located in the same layer, and the other two connect to two different outer layers. Despite their different motifs, the area densities of the three layers are almost equal. The other structure is a flat hexagonal bilayer ice produced at wall separation of 0.8 nm under lateral pressure of 100 MPa, analogous to a system demonstrated by Koga et al. [Phys. Rev. Lett. 79, 5262 (1997)]. Both first-order and continuous phase transitions take place in these simulations.
GPCR A2AAR Agonist Binding and Induced Conformation Changes of Functional Switches
Authors: Pang Xue-qin , Liu Jian-yong
Published: March 2014

Agonist binding of A2A adenosine receptor (A2AAR) shows protective effects against inflammatory and immune. Efforts are exerted in understanding the general mechanism and developing A2AAR selectively binding agonists. Using molecular dynamics (MD) simulations, we have studied the interactions between A2AAR and its agonist (adenosine), and analyzed the induced dynamic behaviors of the receptor. Key residues interacting with adenosine are identified: A632.61, I662.64, V843.32, L853.33, T883.36, F1685.29, M1775.38, L2496.51, H2506.52, and N2536.55 interacting with adenosine with affinities larger than 0.5 kcal/mol. Moreover, no interaction between adenosine and L1675.28 is observed, which supports our previous findings that L1675.28 is an antagonist specific binding reside. The dynamic behaviors of agonist bound A2AAR are found to be different from apo-A2AAR in three typical functional switches: (i) tight “ionic lock” forms in adenosine-A2AAR, but it is in equilibrium between formation and breakage in apo-A2AAR; (ii) the “rotamer toggle switch”, T883.36/F2426.44/W2466.48, adopted different rotameric conformations in adenosine-A2AAR and apo-A2AAR; (iii) adenosine-A2AAR has a flexible intracellular loop 2 (IC2) and α-helical IC3, while apo-A2AAR preferred α-helical IC2 and flexible IC3. Our results indicate that agonist binding induced different conformational rearrangements of these characteristic functional switches in adenosine-A2AAR and apo-A2AAR.
Effect of Ar+, He+, and S+ Irradiation on n-InP Single Crystal
Authors: Hu Jing-yu , Mahmood Waqas , Zhao Qing
Published: March 2014

The irradiation effects of Ar+, He+ and S+ with energy from 10 eV to 180 eV on n-InP(100) surface are analyzed by X-ray photoelectron spectroscopy and low energy electron diffraction. After irradiation on the n-InP surface, damage on the surface, displacement of the Fermi level and formation of sulfur species on S+ exposed surface are found and studied. Successive annealing is done to suppress the surface states introduced by S+ exposure. However, it is unsuccessful in removing the damage caused by noble ions. Besides, S+ ions can efficiently repair the Ar+ damaged surface, and finally form a fine 2×2 InP surface.
Spontaneous Cracking of Graphite Oxide Sheet on Oxygen Deficient ZnO Film
Authors: Liu Jin-yang , Hong-bin Cai , Ding Huan-yi , Zhang Kun , Pan Nan , Wang Xiao-ping
Published: March 2014

Graphite oxide (GO) is an important material of wide applications. Owing to its good mechanical property, the GO sheet is always expected to be stable and remains flat on various substrates. Here we demonstrate for the first time an unexpected behavior of the GO sheet on oxygen deficient ZnO film, namely the spontaneous cracking of the entire GO sheet into many small pieces. This unusual behavior has been carefully investigated by a series of control experiments and SEM, XPS and PL measurements. It is anticipated that the oxygen vacancies in the oxygen deficient ZnO film can annihilate epoxy groups of the GO sheet, resulting in the unzipping of the aligned epoxy groups on GO sheet. A prototype of the white light detector made from the cracked GO sheet is fabricated and the device demonstrates high stability and good reproducibility.
Time spent on daytime direct care activities by personal carers in two Australian residential aged care facilities: a time–motion study
Authors: Qian Siyu , Yu Ping , Hailey David M. , Zhang Zhenyu , Davy Pamela J. , Nelson Mark I.
Published: March 2014

Objective
To examine the time, frequency and duration of each direct care activity conducted by personal carers in Australian residential aged care homes.

Methods
A time–motion study was conducted to observe 46 personal carers at two high-care houses in two facilities (14 days at Site 1 and 16 days at Site 2). Twenty-three direct care activities were classified into eight categories for analysis.

Results
Overall, a personal carer spent approximately 45% of their time on direct care, corresponding to 3.5 h in an 8-h daytime shift. The two sites had similar ratios of personal carers to residents, and each resident received 30 min of direct care. No significant differences between the two sites were found in the time spent on oral communication, personal hygiene and continence activities. Personal carers at Site 1 spent significantly less time on toileting and mobility activities than those at Site 2, but more time on lunch activity. Although oral communication took the longest time (2 h), it occurred concurrently with other activities (e.g. dressing) for 1.5 h.

Conclusions
The findings provide information that may assist decision makers in managing the operation of high-care residential aged care facilities, such as planning for task allocation and staffing.

What is known about the topic?
Overall, 30%–45% of the care staff’s time is spent on direct care in residential aged care facilities.

What does this paper add?
This paper adds knowledge about how much time is required to conduct each direct care activity and the frequency and duration of conducting these activities to meet residents’ day-to-day care needs in two high-care houses in two aged care facilities.

What are the implications for practitioners?
On average, a resident with high-care needs requires 30 min direct care. There may exist a basic minimum desirable ratio of personal carers to residents in high-care facilities. Residents’ toileting needs are high after meals. Communication with residents represents an essential role in providing care.
Fruit presence negatively affects photosynthesis by reducing leaf nitrogen in almond
Authors: Saa Sebastian , Brown Patrick H.
Published: March 2014

Fruit presence often positively and seldom negatively affects leaf carbon assimilation rate in fruit-trees. In almond (Prunus dulcis (Mill.) DA Webb) the presence of fruit often results in the death of the fruit bearing spurs. The mechanism of this effect is unclear, but may be a consequence of diminished carbon assimilation rate in leaves adjacent to fruit and the subsequent depletion of nutrient and carbohydrates reserves. This study evaluated the influence of fruit on leaf carbon assimilation rate and leaf nitrogen throughout the season. Carbon assimilation rate (Aa), rubisco carboxylation capacity at leaf temperature (Vcmax@Tleaf), maximum rate of RubP regeneration at leaf temperature (Jmax@Tleaf), leaf nitrogen on a mass basis (N%) and area basis (Na), and specific leaf weight data were recorded. Fruit presence negatively affected leaf nitrogen concentration by a reduction in specific leaf weight and leaf nitrogen content. The impact of fruit presence on carbon assimilation rate was predominantly associated with the negative effect of fruit on Na and resulted in a significant reduction in Jmax@Tleaf and therefore in Aa, especially after full leaf and fruit expansion. The reduction in leaf area, leaf nitrogen, reduced Jmax@Tleaf and decreased carbon assimilation rate in the presence of fruit explains the negative effects of fruit presence on spur vitality.
Ram spermatozoa migrating through artificial mucus in vitro have reduced mitochondrial membrane potential but retain their viability
Authors: Martínez-Rodríguez Carmen , Alvarez Mercedes , López-Urueña Elena , Gomes-Alves Susana , Anel-López Luis , Chamorro Cesar A. , Anel Luis , de Paz Paulino
Published: March 2014

Sperm motility in vitro is one of the most common predictors of fertility in male screening. We propose that a mucus-penetration assay can isolate a cellular subpopulation critical to reproductive success. To this end, a device was designed with three modules (sample, test and collection) and its conditions of use evaluated (length of mucus, incubation time, mucus medium, sperm concentration and position in relation to the horizontal). The number of spermatozoa migrating and the viability and acrosomal status of the spermatozoa not migrating were calculated. The second objective was to evaluate the qualitative parameters of the spermatozoa migrating in 1.6% polyacrylamide for 30 min. The number of spermatozoa migrating and the sperm motility, viability and the acrosomal and mitochondrial status of three sperm populations (fresh, not migrating and migrating) were determined. A higher number of migrating spermatozoa were observed after 60 min of incubation, but this situation adversely affected sperm quality. The methylcellulose-based test showed a significantly lower number of migrating spermatozoa than the polyacrylamide test. The position at an angle of 45° resulted in a higher number of migrating spermatozoa in the polyacrylamide-based test. The sperm counts for three consecutive assays indicated an acceptable repeatability of the method. The viability and acrosomal status of the migrating spermatozoa showed no significant changes with regard to the control when the device was placed at 45°, whereas these parameters showed lower values at 0°. The percentage of high mitochondrial membrane potential spermatozoa was significantly reduced in the population of migrating spermatozoa.
Variation in soil microbial biomass in the dry tropics: impact of land-use change
Authors: Singh Mahesh Kumar , Ghoshal Nandita
Published: March 2014

The impact of land-use change on soil microbial biomass carbon (C) and nitrogen (N) was studied through two annual cycles involving natural forest, degraded forest, agroecosystem and Jatropha curcas plantation. Soil microbial biomass C and N, soil moisture content and soil temperature were analysed at upper (0–10 cm), middle (10–20 cm) and lower (20–30 cm) soil depths during the rainy, winter and summer seasons. The levels of microbial biomass C and N were highest in the natural forest, followed in decreasing order by Jatropha curcas plantation, degraded forest and the agroecosystem. The highest level of soil microbial biomass C and N was observed during summer, decreasing through winter to the minimum during the rainy season. Soil microbial biomass C and N decreased with increasing soil depth for all land-use types, and for all seasons. Seasonal variation in soil microbial biomass was better correlated with the soil moisture content than with soil temperature. The microbial biomass C/N ratio increased with the soil depth for all land-use types, indicating changes in the microbial community with soil depth. It is concluded that the change in land-use pattern, from natural forest to other ecosystems, results in a considerable decrease in soil microbial biomass C and N. Jatropha plantation may be an alternative for the restoration of degraded lands in the dry tropics.
Complexin synchronizes primed vesicle exocytosis and regulates fusion pore dynamics
Authors: Dhara Madhurima , Yarzagaray Antonio , Schwarz Yvonne , Dutta Soumyajit , Grabner Chad , Moghadam Paanteha K. , Bost Anneka , Schirra Claudia , Rettig Jens , Reim Kerstin , Brose Nils , Mohrmann Ralf , Bruns Dieter
Published: March 2014

ComplexinII (CpxII) and SynaptotagminI (SytI) have been implicated in regulating the function of SNARE proteins in exocytosis, but their precise mode of action and potential interplay have remained unknown. In this paper, we show that CpxII increases Ca2+-triggered vesicle exocytosis and accelerates its secretory rates, providing two independent, but synergistic, functions to enhance synchronous secretion. Specifically, we demonstrate that the C-terminal domain of CpxII increases the pool of primed vesicles by hindering premature exocytosis at submicromolar Ca2+ concentrations, whereas the N-terminal domain shortens the secretory delay and accelerates the kinetics of Ca2+-triggered exocytosis by increasing the Ca2+ affinity of synchronous secretion. With its C terminus, CpxII attenuates fluctuations of the early fusion pore and slows its expansion but is functionally antagonized by SytI, enabling rapid transmitter discharge from single vesicles. Thus, our results illustrate how key features of CpxII, SytI, and their interplay transform the constitutively active SNARE-mediated fusion mechanism into a highly synchronized, Ca2+-triggered release apparatus.
Uniform nomenclature for the mitochondrial contact site and cristae organizing system
Authors: Pfanner Nikolaus , van der Laan Martin , Amati Paolo , Capaldi Roderick A. , Caudy Amy A. , Chacinska Agnieszka , Darshi Manjula , Deckers Markus , Hoppins Suzanne , Icho Tateo , Jakobs Stefan , Ji Jianguo , Kozjak-Pavlovic Vera , Meisinger Chris , Odgren Paul R. , Park Sang Ki , Rehling Peter , Reichert Andreas S. , Sheikh M. Saeed , Taylor Susan S. , Tsuchida Nobuo , van der Bliek Alexander M. , van der Klei Ida J. , Weissman Jonathan S. , Westermann Benedikt , Zha Jiping , Neupert Walter , Nunnari Jodi
Published: March 2014

The mitochondrial inner membrane contains a large protein complex that functions in inner membrane organization and formation of membrane contact sites. The complex was variably named the mitochondrial contact site complex, mitochondrial inner membrane organizing system, mitochondrial organizing structure, or Mitofilin/Fcj1 complex. To facilitate future studies, we propose to unify the nomenclature and term the complex “mitochondrial contact site and cristae organizing system” and its subunits Mic10 to Mic60.
Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps
Authors: Vedovato Natascia , Gadsby David C.
Published: March 2014

A single Na+/K+-ATPase pumps three Na+ outwards and two K+ inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na+ than K+ generates outward current across the cell membrane. Less well understood is the ability of Na+/K+ pumps to generate an inward current of protons. Originally noted in pumps deprived of external K+ and Na+ ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K+ and Na+ concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na+ release from phosphorylated Na+/K+ pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na+/K+ pumps that enables proton import is not required for completion of the 3 Na+/2 K+ transport cycle. However, the back-step occurs readily during Na+/K+ transport when external K+ ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na+-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na+ and K+ ions that passes through binding site II. The inferred occurrence of Na+/K+ exchange and H+ import during the same conformational cycle of a single molecule identifies the Na+/K+ pump as a hybrid transporter. Whether Na+/K+ pump–mediated proton inflow may have any physiological or pathophysiological significance remains to be clarified.