bluuebunny/crossref_metadata_2025 huggingface dataset:
Crystal structures and band‐gap energies of Cu2Sn(S,Se)3 (0≤ x ≤1.0) solid solution
Authors: Nomura Takeshi , Maeda Tsuyoshi , Takei Kouji , Morihama Masaru , Wada Takahiro
Published: May 2013

Cu2Sn(S1–xSex)3 (CTSSe) solid solutions with 0 ≤ x ≤ 1.0 were synthesized by mixing the elemental powders and post‐annealing at 600 °C. The crystal structure of Cu2SnS3 (CTS), Cu2SnSe3 (CTSe), and their solid solution were determined by Rietveld refinement of the powder X‐ray diffraction data. CTSSe solid solution had a monoclinic crystal system [space group: Cc (No. 9)]. The refined lattice parameters of CTS were a =6.654(8) Å, b =11.534(2) Å, c =6.659(4) Å, and β =109.40(5)° and those of CTSe were a =6.964(6) Å, b =12.056(6) Å, c =6.972(4) Å, and β =109.49(1)°. The lattice parameters, a, b, and c of CTSSe solid solution monotonically increased with increasing Se content. The band gap of the CTSSe solid solution linearly decreased from 0.87 eV (x=0.0) to 0.67 eV (x=0.60) with increasing Se content. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Excitonic emissions of AgInS2 crystals with chalcopyrite and orthorhombic structure
Authors: Wakita Kazuki , Miyamoto Umihito , Paucar Raul , Honjo Kazuhiro , Shim YongGu , Tokuda Takahiro , Yoshino Kenji
Published: May 2013

Micro‐structure of AgInS2 grown by the hot‐press method has been examined by the properties of free‐exciton emission using a scanning confocal‐microscopy system. The crystal structures are distinguished by a two‐dimensional image of free‐exciton emission at RT. The excitonic emissions with the orthorhombic structure were also analyzed and a bound exciton emission was observed in addition to a free exciton emission. Furthermore, it is indicated that the two‐dimensional image of decay‐time constant is more insusceptible to resolve the structures than that of emission intensity. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plasmonic protection of the hot‐electron energy
Authors: Kempa Krzysztof
Published: May 2013

It is shown, that hot electrons generated in a semiconductor can transfer their excess free energy into an embedded/adjacent plasmonic metallic structure (reservoir), before it is lost irreversibly to phonons in the semiconductor. Since the plasmon–phonon (and plasmon–photon) scattering in the metallic structure could be much slower than the electron–phonon scattering in the semiconductor, free energy of the hot electrons can be this way effectively protected from phonon emission for a significant amount of time. While the cubic point‐dipole crystal is proposed and studied here specifically as the plasmonic reservoir, other plasmonic structures including planar can be employed. It is also shown how the plasmon‐protected energy can by recycled in a novel, 3rd generation solar cell, be employing a planar plasmonic structure that is simultaneously also an electron collector of the cell. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Intermolecular interactions in uracil–nitrous acid complexes: structures, binding energy, topological properties, and nuclear magnetic resonance study
Authors: Makiabadi Batoul , Zakarianejad Mohammad , Bagheri Sotoodeh , Masoodi Hamid Reza , Aghaie Raziyeh Sadaat
Published: May 2013

Molecular interactions between uracil and nitrous acid (U–NA) [C4N2O2H4NO2H] have been studied using B3LYP, B3PW91, and MP2 methods with different basis sets. The optimized geometries, harmonic vibrational frequencies, charge transfer, topological properties of electron density, nucleus‐independent chemical shift (NICS), and nuclear magnetic resonance one‐ and two‐bonds spin–spin coupling constants were calculated for U–NA complexes. In interaction between U and NA, eight cyclic complexes were obtained with two intermolecular hydrogen bonds N(C)HU…N(O) and OHNA…OU. In these complexes, uracil (U) simultaneously acts as proton acceptor and proton donor. The most stable complexes labeled, UNA1 and UNA2, are formed via NH bond of U with highest acidity and CO group of U with lowest proton affinity. There is a relationship between hydrogen bond distances and the corresponding frequency shifts. The solvent effect on complexes stability was examined using B3LYP method with the aug‐cc‐pVDZ basis set by applying the polarizable continuum model (PCM). The binding energies in the gas phase have also been compared with solvation energies computed using the PCM. Natural bond orbital analysis shows that in all complexes, the charge transfer takes place from U to NA. The results predict that the Lone Pair (LP)(O)U → σ*(OH) and LP(N(O)NA → σ*(N(C)H)U donor–acceptor interactions are most important interactions in these complexes. Atom in molecule analysis confirms that hydrogen bond contacts are electrostatic in nature and covalent nature of proton donor groups decreases upon complexation. The relationship between spin–spin coupling constant (1hJH…Y and 2hJH…Y) with interaction energy and electronic density at corresponding hydrogen bond critical points and H‐bonds distances are investigated. NICS used for indicating of aromaticity of U ring upon complexation. © 2013 Wiley Periodicals, Inc.
β‐D‐Glucosidase Assisted Gold Dissolution as Non‐Optical and Quantifiable Detection Technique for Immunoassays
Authors: Koehler F. M. , Raso R. A. , Grass R. N. , Stark W. J.
Published: May 2013

Immunoassays are used for detecting protein targets for various applications. Here, a modification of immunoassays to allow a purely electrical detection of the target protein concentration is shown. The modification comprises a β‐D‐glucosidase as reporter enzyme and a cyanogenic glycoside as substrate. The enzymatic reaction produces cyanide in small quantities. For electrical detection of the cyanide, a novel sensor is developed, based on a gold micro wire. The cyanide dissolves the gold wire and changes the electrical resistance of the wire. Monitoring the resistance change allows a quantitative measurement of the target human C‐reactive protein (an inflammatory marker) in blood plasma in the physiological relevant concentration range.
Adiabatic Carbon Rate of Alternative Ironmaking Processes to Produce Hot Metal
Authors: Jiang Xin , Wang Lin , Shen Fengman , Lu Weikao
Published: May 2013

From economic viability and sustainable development of view, the future alternative ironmaking processes, in general, may be classified into two representative routes, “Pre‐reduction‐Smelting reduction” process and “Direct reduction‐Melting” process. In the present work, aimed for hot metal production, the carbon rate (in kg tHM−1) is considered as the yardstick for the measurement of the “goodness” of these two processes, because it reflects the consumption of coal and energy, and the amount of carbon dioxide eventually to be emitted to atmosphere. By the thermodynamic calculation, under the idealized conditions, the total adiabatic carbon rate along “Direct reduction‐Melting” process is approximately 145 kg tHM−1 lower than that along “Pre‐reduction‐Smelting reduction” process. Therefore, direct reduction would likely lead to an alternative process with much lower carbon rate, and it should be reasonable and successfully developed.
Learning from Experience: Recollections of Working with Howard S. Becker
Authors: Sanders Clinton R.
Published: May 2013

Howard S. Becker is, and has been, a major figure in contemporary sociology, especially within the symbolic interactionist perspective. This discussion describes my initial encounter with Howie in the mid‐1960s and moves to identify the substantive and methodological areas in which he has had major impact. I then briefly outline various ways in which the foci of my own work have been shaped by Becker's instruction and example.
Inhabitants Moving In: Prospective Sense‐Making and the Reproduction of Inhabited Institutions in Teacher Education
Authors: Everitt Judson G.
Published: May 2013

This article advances the scholarship on inhabited institutions with analysis of the professional socialization of new teachers. My findings show that incoming teachers develop a perspective I call an “injunction to adapt” to prospective classroom contingencies, and define this as fundamental to effective teaching. Teacher candidates become primed to perform prospective work in ways that are tightly‐coupled with institutional mandates of public schools in some ways, and loosely‐coupled with them in others. I argue that attention to professional socialization highlights the ways that people's sense‐making can be prospective and anticipatory as well as ongoing and retrospective. Furthermore, I argue that analyzing professional socialization as a process of “interpretive reproduction” offers fruitful opportunity to wed the key strengths of symbolic interactionism with new institutionalism, as it reveals ways in which interaction and sense‐making can serve to reproduce and maintain the legitimacy of institutional logics while also serving as a source of individual creativity.
Oceanic sources of continental precipitation and the correlation with sea surface temperature
Authors: van der Ent Rudi J. , Savenije Hubert H. G.
Published: May 2013

Identifying the sources of continental precipitation has received increasing attention in recent years. With the use of various numerical methods, sources of precipitation have been identified from local to global scales. In this paper we identify the oceanic sources based on an atmospheric backtracking analysis of continental precipitation. We find that the strongest source areas are located close to the continents. In general, we define an oceanic area as a significant source when on average more than 20% of the total evaporation, and at least 250 mm/yr of evaporation ends up as continental precipitation. We grouped these identified source areas into 15 regions and performed a forward tracking analysis of oceanic evaporation. We identified the areas on the adjacent continents that receive this oceanic moisture and whether this is nearby or remote. Moreover, we showed how the oceanic sources vary over the year in time and space. Furthermore, we correlated sea surface temperatures (SSTs) in the 15 source regions and the Niño 3.4 region with precipitation on all continents. For South America, we found that the El Niño Southern Oscillation (altering wind patterns) has a larger effect on precipitation than local SSTs. For West Africa, however, we show that SST in the source regions is strongly correlated with precipitation in the rainy season. In Australia, both local SST and the Niño 3.4 region appear to have a big influence on precipitation. As such this research provides new insight in the ocean‐atmosphere‐land coupling, which can be useful for studying seasonal weather predictions as well as climate change impact.
K13CoSn17–x (x = 0.1): A New Ternary Phase Containing ­Cobalt Centered [Sn9] Cluster Synthesized via High‐Temperature Reaction
Authors: Yue Cheng‐Yang , Wang Ming‐Feng , Yuan Zhuang‐Dong , Zhou Fang‐Xia , Zhang Hui‐Ping , Lei Xiao‐Wu
Published: May 2013

A new ternary potassium cobalt stannide, K13CoSn17–x (x = 0.1), was obtained by reacting the mixture of the corresponding pure elements at high temperature, and structurally characterized by single‐crystal X‐ray diffraction study. K13CoSn17–x (x = 0.1) crystallizes in the orthorhombic space group Pbca (No. 61) with a = 26.2799(7) Å, b = 24.1541(6) Å, c = 29.8839(6) Å, V = 18969.3(8) Å3, and Z = 16. Its structure contains isolated [CoSn9] monocapped square antiprism and [Sn4] tetrahedron in the ratio 1:2, forming a hierarchical variant of Laves phase MgZn2. The structural relation between the title compound with MgZn2 as well as other binary stannides is also discussed.
THE WATER RELATIONS AND IRRIGATION REQUIREMENTS OF MANGO (Mangifera indicaL.): A REVIEW
Authors: CARR M. K. V.
Published: May 2013

The results of research on the water relations and irrigation requirements of the mango fruit tree are collated. The stages of development (including roots) are summarised, followed by reviews of plant water relations, water requirements, water productivity and water management. This long-lived tree is well adapted to a wide range of tropical and subtropical environments. In the low-latitude tropics, flowering is initiated after a period of water stress (at least six weeks duration) and is ended by rain or irrigation. In the high-latitude tropics and subtropics, flower buds are initiated during the cool winter months (<15 °C). Less than 1% of the flowers that set fruit reach maturity. Roots can reach depths of 5 m. Stomata occur mainly on the lower (abaxial) leaf surface. They are sensitive to dry air, closing as the saturation deficit increases (from 0.5 to 4.0 kPa). In humid tropical areas, the mean seasonal potential evapotranspiration rates (ETc) average 4–5 mm d−1, with peak rates of 5–6 mm d−1. The crop coefficient (Kc) varies between 0.65 and 1.05. Water productivities are in the range 3–6 kg (fresh fruit) m−3(irrigation). Micro-sprinklers and drip irrigation are the preferred methods of irrigation. The trend towards greater intensification of production will impact on the water relations and irrigation needs of mango and provide a focus for future research.
Effect of high pressure on the structure and antibacterial activity of bovine lactoferrin treated in different media
Authors: Franco Indira , Pérez Mańa. D. , Castillo Eduardo , Calvo Miguel , Sánchez Lourdes
Published: May 2013

The effect of high-pressure treatment (400, 500 and 650 MPa) on the structure and activity of bovine lactoferrin in different iron-saturation forms has been studied by several techniques. The structural changes produced in lactoferrin by high-pressure were analysed by differential scanning calorimetry and fluorescence spectroscopy, and the immunoreactivity by ELISA. The effect of high-pressure was also studied on some biological properties of lactoferrin, such as iron binding capacity, retention of the bound iron, and antibacterial activity against Escherichia coli O157:H7. Results obtained indicate that treatment at 400 MPa does not substantially modify the conformation of lactoferrin, meanwhile treatments at 500 and 650 MPa greatly affect some of its properties. With respect to the antibacterial activity, the apo and native forms of lactoferrin maintain that activity against Esch. coli only after 400 MPa treatment.
The Arctic Council and the Search and Rescue Agreement: the case of Norway
Authors: Rottem Svein Vigeland
Published: May 2013

On 12 May 2011 at the seventh ministerial meeting, the member states of the Arctic Council (AC) signed the Arctic SAR agreement, the first legally binding agreement negotiated under the auspices of the AC. Its objective is to strengthen search and rescue cooperation and coordination in the Arctic. The purpose of this article is to explore why an agreement on search and rescue under the auspices of the AC has been negotiated; what its key features are; and lastly, how it is and will be implemented. It is argued that the SAR agreement is more important for the AC than for Norway. It has had limited practical consequences in that country. The agreement may be politically and symbolically significant but it has neither financially nor organisationally changed Norwegian search and rescue policy.
Transdiagnostic and disorder-specific models of intergenerational transmission of internalizing pathology
Authors: Starr L. R. , Conway C. C. , Hammen C. L. , Brennan P. A.
Published: May 2013

Background

Numerous studies have supported an association between maternal depression and child psychiatric outcomes, but few have controlled for the confounding effects of both maternal and offspring co-morbidity. Thus, it remains unclear whether the correspondence between maternal and offspring depressive and anxiety disorders is better explained by associations between shared features of maternal and offspring internalizing disorders or by specific effects exerted by unique aspects of individual disorders.

Method

Pairs of mothers and offspring overselected for maternal depression (n = 815) were assessed at offspring age 15 years for anxiety and depressive disorders; 705 completed a follow-up at offspring age 20 years. For both mothers and offspring, structural equation modeling was used to distinguish transdiagnostic internalizing pathology – representing the overlap among all depressive and anxiety disorders – from diagnosis-specific forms of pathology. To discriminate between general versus specific pathways of intergenerational transmission of psychopathology, we examined (a) the general association between the maternal and offspring internalizing factors and (b) the correlations between maternal and offspring diagnosis-specific pathology for each disorder.

Results

For mothers and offspring, a unidimensional latent variable model provided the best fit to the correlations among depressive and anxiety disorders. The maternal transdiagnostic internalizing factor strongly predicted the corresponding factor among offspring. In addition, the unique component of post-traumatic stress disorder among offspring was significantly related to the analogous unique component among mothers, but specific components of other maternal disorders, including depression, did not predict corresponding offspring pathology.

Conclusions

Results suggest that intergenerational transmission of internalizing disorders is largely non-specific.
Secret Codes of Political Propaganda: The Unknown System of Writing Teams
Authors: Tsai Wen-Hsuan , Kao Peng-Hsiang
Published: May 2013

Within the Chinese Communist Party (CCP), some Party units have established a largely unknown network of writing teams which propagate the policies or perspectives of a particular unit by publishing feature articles in Party journals. These writing teams often make use of a pseudonym in the form of a person's name, leading outsiders to believe that the work is written by a journalist. In fact, the pseudonyms of the Party unit writing teams function as a form of secret code. Through this code, inner Party members can recognize which unit's views an article reflects. In order to reveal exactly which units the codes represent, we have collated the names of over 20 writing teams. In addition, we provide an introduction to the functioning of the writing teams and the manner in which articles are produced. Finally, we propose that the CCP's mechanism of “propaganda codes” is gradually undergoing the process of institutionalization.
Spontaneous regression of a large rhabdomyoma of the interventricular septum
Authors: Milano Elena G. , Prioli Maria A. , Vassanelli Corrado
Published: May 2013

We report the case of a large congenital rhabdomyoma of the interventricular septum diagnosed prenatally. The foetus was strictly monitored with ultrasound throughout the gestation period showing that the mass had increased in size until delivery. Despite the size of the mass, which appeared to occupy the right ventricle, the baby presented no symptoms both in utero and after birth. Serial echocardiography was used to document the regression of the mass in childhood.
The Differential Effects of Written and Spoken Presentation for the Modification of Interpretation and Judgmental Bias in Children
Authors: Vassilopoulos Stephanos P. , Blackwell Simon E. , Misailidi Plousia , Kyritsi Alexandra , Ayfanti Maria
Published: May 2013

Background: Interpretation training programs, in which individuals are trained to interpret ambiguous scenarios in either a negative or benign way, have proven effective in altering anxiety-related cognitive biases in both children and adults. Aims: The current study investigated whether the effects of the interpretation training procedure in children are differentiated according to the mode of presentation of the training. Method: Ninety-four primary school children (aged 10–12 years) scoring above the mean on a social anxiety scale were randomly allocated to four groups, in which they were trained using written or spoken presentation of training materials in either the negative or benign direction. Results: For the negative training, children who heard the training material spoken aloud (spoken presentation) made more negative interpretations of ambiguous social events, compared to children who read the training material (written presentation). However, for the benign training, there was less clear evidence for a differentiation of the effects between the two modes of presentation, although children in the spoken presentation group performed better in a stressful task and showed a trend to rate their mood as more positive after the task than children in the written presentation group. Conclusions: These results not only forward our understanding of the mechanism of the genesis of cognitive bias in children, but also highlight the need for further investigation of how to optimize the effectiveness of interpretation training in children.
Electron Backscatter Diffraction in Conservation Science: Phase Identification of Pigments in Paint Layers
Authors: Gambirasi A. , Peruzzo L. , Bianchin S. , Favaro M.
Published: May 2013

Electron backscatter diffraction (EBSD) was used in Conservation Science for characterization of ancient materials collected from works of art. The results demonstrate the feasibility of EBSD analysis on heterogeneous matrices as very small samples of paint layers collected from paintings. Two reference pigments were selected from those used by artists to investigate the relationship existing between EBSD pattern quality and properties of the investigated material (i.e., average atomic number, density, and Mohs hardness). The technique was also tested to investigate the pigment phases on two real samples collected from Romanino's Santa Giustina altarpiece, an oil on wood painting dated 1514 (Civic Museum, Padova, Italy). Results show for the first time the acquisition of EBSD patterns from painting samples mounted in resin, i.e., painting cross sections, opening a new powerful tool to elucidate the pigment phases avoiding large sampling on works of arts and to further study the complex mechanisms of pigment deterioration.
Inherited Fabric in an Omphacite Symplectite: Reconstruction of Plastic Deformation under Ultra-High Pressure Conditions
Authors: Heidelbach Florian , Terry Michael P.
Published: May 2013

We investigated an eclogitic gneiss from the Western Gneiss Region in Norway, which underwent subduction as part of Baltica lithosphere beneath Laurentia during the Scandian orogeny. Petrologic data indicate that the eclogite was deformed plastically at about 4 GPa and 800°C producing a strong macroscopic foliation and lineation. Whereas garnet remained largely stable during the retrograde uplift, omphacite was transformed statically into a symplectite consisting of lamellar diopside and plagioclase with more equant grains of hornblende and orthopyroxene. Measurements of the crystallographic preferred orientation with electron backscatter diffraction show that diopside and hornblende, as well as orthopyroxene, have a systematic orientation relationship with the macroscopic fabric, as well as the (presumed) orientation of the host omphacite. The orientation relationship between the chain silicates is very sharp with the crystallographic forms {100}, {010}, and ⟨001⟩ being parallel. Their bulk texture shows a maximum of ⟨001⟩ parallel to the lineation and girdles of {010} and {110} perpendicular to the lineation with maxima subparallel to the foliation corresponding to an L-type texture of the original omphacite and indicating constrictional strain with an additional component of pure shear/simple shear component.
Is it Really God's Century? An Evaluation of Religious Support and Discrimination from 1990 to 2008
Authors: Fox Jonathan
Published: May 2013

This study uses data from the Religion and State Round 2 dataset to examine the trends in religious discrimination and religious support between 1990 and 2008, finding a statistically significant increase in both variables. These findings are based on a longer time span and more comprehensive variables than previous studies, remain constant when controlling for world region and majority religion, and predate the events of September 11, 2001. This undermines the aspects of secularization theory which predict a decline in religion's public influence. Furthermore, economic development, one of the processes predicted by secularization theory decrease religion's public influence, is correlated with increased religious discrimination and support.
The Fight Against the Illicit Trade in Asian Cultural Artefacts: Connecting International Agreements, Regional Co-operation, and Domestic Strategies
Authors: GRUBER Stefan
Published: May 2013

Looting and illicit trafficking of cultural artefacts pose major threats to Asia's cultural heritage. This not only causes a continuing loss of cultural objects but also the destruction of large numbers of archaeological and historical sites as objects are often looted from tombs or cut off from larger pieces in order to obtain transportable parts for sale on the international art market. In addition, items are stolen from collections and museums or are trafficked in violation of export bans. This article explores the relevant international conventions dealing with the prevention of the illicit export of cultural artefacts and their repatriation, examines how those legal instruments are implemented in Asia and extended in bilateral agreements between market and source countries, and how particularly regional co-operation between Asian nations, international solidarity and assistance, and relevant domestic approaches can assist in improving the situation.
Personal Perspective
Authors: Scheraga Harold A.
Published: May 2013

A personal perspective of biomolecular modeling and simulation.
Parathyroid hormone-related protein is induced by hypoxia and promotes expression of the differentiated phenotype of human articular chondrocytes
Authors: Pelosi Michele , Lazzarano Stefano , Thoms Brendan L. , Murphy Chris L.
Published: May 2013

PTHrP (parathyroid hormone-related protein) is crucial for normal cartilage development and long bone growth and acts to delay chondrocyte hypertrophy and terminal differentiation in the growth plate. After growth plate closure adult HACs (human articular chondrocytes) still produce PTHrP, suggesting a possible role for this factor in the permanent articular cartilage. However, the expression regulation and function of PTHrP in the permanent articular cartilage is unknown. Human articular cartilage is an avascular tissue and functions in a hypoxic environment. The resident chondrocytes have adapted to hypoxia and use it to drive their tissue-specific functions. In the present study, we explored directly in normal articular chondrocytes isolated from a range of human donors the effect of hypoxia on PTHrP expression and whether PTHrP can regulate the expression of the permanent articular chondrocyte phenotype. We show that in HACs PTHrP is up-regulated by hypoxia in a HIF (hypoxia-inducible factor)-1α and HIF-2α-dependent manner. Using recombinant PTHrP, siRNA-mediated depletion of endogenous PTHrP and by blocking signalling through its receptor [PTHR1 (PTHrP receptor 1)], we show that hypoxia-induced PTHrP is a positive regulator of the key cartilage transcription factor SOX9 [SRY (sex determining region on the Y chromosome)-box 9], leading to increased COL2A1 (collagen type II, α1) expression. Our findings thus identify PTHrP as a potential factor for cartilage repair therapies through its ability to promote the differentiated HAC phenotype.
In-process estimation of time-variant contingently correlated measurands
Authors: D’Errico G. E. , Murru N.
Published: May 2013

This paper is devoted to the study and implementation of real-time techniques for the estimation of time-varying, contingently correlated quantities, and relevant uncertainty. An estimation algorithm based on a metrological customization of the Kalman filtering technique is presented, starting from a Bayesian approach. Moreover, a fuzzy-logic routine for real-time treatment of possible outliers is incorporated in the overall software procedure. The system applicability is demonstrated by results of simulations performed on dimensional measurement models.
Sampling strategies and long term variation modelling for a statistical feed-forward controller
Authors: Hernández C. , Tutsch R.
Published: May 2013

The Statistical Feed-Forward Control Model (SFFCM) relies on a sequence of specification adjustments made on subsets of a population to counter the influence of the long time component of the variation. The difficulty strives in finding a proper estimate for the measure of the central tendency of each subset to minimize the number of the required adjustments. By means of simulating the assembly of two components having high dimensional variation, forty experiments were designed to compare the individual influence of different factors such as the number of adjustments, the sampling strategy and two measures of central tendency: the sample mean and the cumulative de-noised average. Simulation results showed that, regardless of the sampling strategy but keeping the inspection rate at 20%, the use of the cumulative de-noised average instead of the sample mean made possible to reduce the number of adjustments by 20%. Thus, while the shift mean of the resulting assembly was decreased by 90%; the standard deviation was reduced by 15%. Hence, the selection of a proper central tendency measure is crucial when modeling the long time variation. The cumulative de-noised average proved to be a valid alternative.
Corrections and input quantities in measurement models
Authors: Pavese F.
Published: May 2013

The Guide to the expression of uncertainty in measurement (GUM) requires, “that the results of a measurement have been corrected for all recognised significant systematic effects and that every effort has been made to identify such effects”, before the issue of evaluating their uncertainty is tackled. In addition, the GUM also requires that a model is used, expressing the functional dependence of the measurand on identified input quantities. The paper discusses the inter-relations between the so-defined two sets of influence quantities and proposes to unify their treatment.
Phase effect in time-stamped accelerometer measurements – an experimental approach
Authors: Moschas F. , Stiros S.
Published: May 2013

The phase error in a high quality accelerometer was investigated on the basis of systematic experiments on a prototype platform permitting controlled vertical harmonic oscillations. The recordings of an accelerometer and of an ultra-high frequency GPS fixed on this platform were compared with those of a LVDT transducer, controlling the platform movement. All sensors were supported by independent GPS timing. The output of this study is that the recordings of accelerometers are characterized by a random phase error, which, however, decreases with the increase of the oscillation frequency, as dictated from the laws of mechanics. Such errors are important given the increasing use of combinations of accelerometers with various sensors for a wide range of applications. A simple method for the correction of such errors is proposed.
Confidence intervals and other statistical intervals in metrology
Authors: Willink R.
Published: May 2013

Typically, a measurement is regarded as being incomplete without a statement of uncertainty being provided with the result. Usually, the corresponding interval of measurement uncertainty will be an evaluated confidence interval, assuming that the classical, frequentist, approach to statistics is adopted. However, there are other types of interval that are potentially relevant, and which might wrongly be called a confidence interval. This paper describes different types of statistical interval and relates these intervals to the task of obtaining a figure of measurement uncertainty. Definitions and examples are given of probability intervals, confidence intervals, prediction intervals and tolerance intervals, all of which feature in classical statistical inference. A description is also given of credible intervals, which arise in Bayesian statistics, and of fiducial intervals. There is also a discussion of the term “coverage interval” that appears in the International Vocabulary of Metrology and in the supplements to the Guide to the Expression of Uncertainty in Measurement.
Optical time domain reflectometry with low noise waveguide-coupled superconducting nanowire single-photon detectors
Authors: Schuck C. , Pernice W. H. P. , Ma X. , Tang H. X.
Published: May 2013

We demonstrate optical time domain reflectometry over 200 km of optical fiber using low-noise NbTiN superconducting single-photon detectors integrated with Si3N4 waveguides. Our small detector footprint enables high timing resolution of 50 ps and a dark count rate of 3 Hz with unshielded fibers, allowing for identification of defects along the fiber over a dynamic range of 37.4 dB. Photons scattered and reflected back from the fiber under test can be detected in free-running mode without showing dead zones or other impairments often encountered in semiconductor photon-counting optical time domain reflectometers.
Direct observation of nanometer-scale Joule and Peltier effects in phase change memory devices
Authors: Grosse Kyle L. , Xiong Feng , Hong Sungduk , King William P. , Pop Eric
Published: May 2013

We measure power dissipation in phase change memory (PCM) devices by scanning Joule expansion microscopy (SJEM) with ∼50 nm spatial and 0.2 K temperature resolution. The temperature rise in the Ge2Sb2Te5 (GST) is dominated by Joule heating, but at the GST-TiW contacts it is a combination of Peltier and current crowding effects. Comparison of SJEM and electrical measurements with simulations of the PCM devices uncovers a thermopower of ∼350 μV K−1 and a contact resistance of ∼2.0 × 10−8 Ω m2 (to TiW) for 25 nm thick films of face centered-cubic crystalline GST. Knowledge of such nanometer-scale Joule, Peltier, and current crowding effects is essential for energy-efficient design of future PCM technology.
Minority current distribution in InGaAs/GaAs transistor-vertical-cavity surface-emitting laser
Authors: Xiang Y. , Yu X. , Berggren J. , Zabel T. , Hammar M. , Akram M. N.
Published: May 2013

We compare experimental data with three-dimensional numerical calculations of the local minority current in an InGaAs/GaAs transistor vertical-cavity surface-emitting laser at different bias levels. It is demonstrated that lateral potential variations within the device greatly affect the transistor operating conditions. As a result, it locally operates in the active mode in the center of the device, allowing for efficient stimulated recombination, while it globally operates in the saturation regime as reflected by the measured current-voltage characteristics. This allows for excellent laser performance, including mW-range output power, sub-mA threshold base current, and continuous-wave operation well above room temperature.
Residual strain and piezoelectric effects in passivated GaAs/AlGaAs core-shell nanowires
Authors: Hocevar Moïra , Thanh Giang Le Thuy , Songmuang Rudeesun , den Hertog Martien , Besombes Lucien , Bleuse Joël , Niquet Yann-Michel , Pelekanos Nikos T.
Published: May 2013

We observe a systematic red shift of the band-edge of passivated GaAs/Al0.35Ga0.65As core-shell nanowires with increasing shell thickness up to 100 nm. The shift is detected both in emission and absorption experiments, reaching values up to 14 meV for the thickest shell nanowires. Part of this red shift is accounted for by the small tensile strain imposed to the GaAs core by the AlGaAs shell, in line with theoretical calculations. An additional contribution to this red shift arises from axial piezoelectric fields which develop inside the nanowire core due to Al fluctuations in the shell.
Interpreting medium ring canonical conformers by a triangular plane tessellation of the macrocycle
Authors: Khalili Pegah , Barnett Christopher B. , Naidoo Kevin J.
Published: May 2013

Cyclic conformational coordinates are essential for the distinction of molecular ring conformers as the use of Cremer-Pople coordinates have illustrated for five- and six-membered rings. Here, by tessellating medium rings into triangular planes and using the relative angles made between triangular planes we are able to assign macrocyclic pucker conformations into canonical pucker conformers such as chairs, boats, etc. We show that the definition is straightforward compared with other methods popularly used for small rings and that it is computationally simple to implement for complex macrocyclic rings. These cyclic conformational coordinates directly couple to the motion of individual nodes of a ring. Therefore, they are useful for correlating the physical properties of macrocycles with their ring pucker and measuring the dynamic ring conformational behavior. We illustrate the triangular tessellation, assignment, and pucker analysis on 7- and 8-membered rings. Sets of canonical states are given for cycloheptane and cyclooctane that have been previously experimentally analysed.
Spherical Schrödinger operators with δ-type interactions
Authors: Albeverio Sergio , Kostenko Aleksey , Malamud Mark , Neidhardt Hagen
Published: May 2013

We investigate spectral properties of spherical Schrödinger operators (also known as Bessel operators) with δ-point interactions concentrated on a discrete set. We obtain necessary and sufficient conditions for these Hamiltonians to be self-adjoint, lower-semibounded and also we investigate their spectra. We also extend the classical Bargmann estimate to such Hamiltonians. In certain cases we express the number of negative eigenvalues explicitly by means of point interactions and the corresponding intensities. We apply our results to Schrödinger operators in \documentclass[12pt]{minimal}\begin{document}$L^2(\mathbb {R}^n)$\end{document}L2(Rn) with a singular interaction supported by an infinite family of concentric spheres.
Strain-driven control of piezoelectricity in (Na,Bi)TiO3-BaTiO3 epitaxial thin films
Authors: Tanaka Y. , Harigai T. , Adachi H. , Sakamoto N. , Wakiya N. , Suzuki H. , Fujii E.
Published: May 2013

Thermal strain effect on the piezoelectricity was investigated for (Na,Bi)TiO3−BaTiO3 (NBT−BT) thin films on various substrates with (100) and (110) orientations. The compressive-thermal strain caused an increase in the remnant polarization unaccompanied by a decrease in dielectric permittivity, which resulted in enhancement of the piezoelectric coefficient, e*31. For films on (110) substrates, the crystal lattices were distorted to orthorhombic symmetry under both the tensile- and compressive-strains and the in-plane anisotropy of piezoelectricity emerged with e*31 as large as −19 to −20.6 C/m2. We conclude that the large piezoelectricity in NBT−BT films on (110) substrates is related to the appearance of orthorhombic phase.
Steady-state simulation of metastable stochastic chemical systems
Authors: Milias-Argeitis Andreas , Lygeros John
Published: May 2013

We address the problem of steady-state simulation for metastable continuous-time Markov chains with application to stochastic chemical kinetics. Such systems are characterized by the existence of two or more pseudo-equilibrium states and very slow convergence towards global equilibrium. Approximation of the stationary distribution of these systems by direct application of the Stochastic Simulation Algorithm (SSA) is known to be very inefficient. In this paper, we propose a new method for steady-state simulation of metastable Markov chains that is centered around the concept of stochastic complementation. The use of this mathematical device along with SSA results in an algorithm with much better convergence properties, that facilitates the analysis of rarely switching stochastic biochemical systems. The efficiency of our method is demonstrated by its application to two genetic toggle switch models.
Dual effect of crowders on fibrillation kinetics of polypeptide chains revealed by lattice models
Authors: Co Nguyen Truong , Hu Chin-Kun , Li Mai Suan
Published: May 2013

We have developed the lattice model for describing polypeptide chains in the presence of crowders. The influence of crowding confinement on the fibrillation kinetics of polypeptide chains is studied using this model. We observed the non-trivial behavior of the fibril formation time τfib that it decreases with the concentration of crowders if crowder sizes are large enough, but the growth is observed for crowders of small sizes. This allows us to explain the recent experimental observation on the dual effect of crowding particles on fibril growth of proteins that for a fixed crowder concentration the fibrillation kinetics is fastest at intermediate values of total surface of crowders. It becomes slow at either small or large coverages of cosolutes. It is shown that due to competition between the energetics and entropic effects, the dependence of τfib on the size of confined space is described by a parabolic function.
Qualitative study of temperature-dependent spin signals in n-Ge-based lateral devices with Fe3Si/n+-Ge Schottky-tunnel contacts
Authors: Hamaya K. , Baba Y. , Takemoto G. , Kasahara K. , Yamada S. , Sawano K. , Miyao M.
Published: May 2013

We study electrical spin injection and detection in n-Ge across Fe3Si/n+-Ge Schottky tunnel barriers. Spin-accumulation signals detected electrically by the three-terminal Hanle-effect measurements have large temperature dependence, and the spin signals disappear at around 200 K. We find that the temperature variation in the spin signals is strongly related to that in the interface resistance of the Fe3Si/n+-Ge contacts. We also observe marked reduction in nonlocal spin-valve signals with increasing temperature in the four-terminal device with almost the same Fe3Si/n+-Ge/n-Ge heterostructure. Note that the nonlocal spin signals depend on not only the measurement temperature but also on the electrical characteristics of the spin injector. Considering the results of three-terminal and four-terminal measurements, we conclude that temperature dependence of the spin signals in our Fe3Si/n+-Ge/n-Ge devices is governed by the electrical characteristics of the spin injector. This study means that it is necessary to consider the effective Schottky-tunnel contacts with the stability on temperature variations for next-generation Ge-based spintronic applications.
Isolated substitutional cobalt and Co-related complexes in silicon
Authors: Scheffler L. , Kolkovsky Vl. , Weber J.
Published: May 2013

Two dominant peaks at EC − 0.39 eV and EV + 0.46 eV previously assigned to substitutional cobalt are shown to belong to different defects by high-resolution Laplace Deep Level Transient Spectroscopy. We assign the level in the upper half of the band gap to substitutional Cos, whereas the level in the lower half is attributed to a CoB pair. No electrically active levels which belong to interstitial Coi was found. Besides the dominant defects, a number of minor DLTS peaks were observed. We correlate these peaks with H-related defects and will also discuss their origin.
Pressure induced para-antiferromagnetic switching in BiFeO3–PbTiO3 as determined using in-situ neutron diffraction
Authors: Comyn Tim P. , Stevenson Tim , Al-Jawad Maisoon , Marshall William G. , Smith Ronald I. , Herrero-Albillos Julia , Cywinski Robert , Bell Andrew J.
Published: May 2013

BiFeO3–PbTiO3 exhibits both ferroelectric and antiferromagnetic order, depending on the composition. Moderate hydrostatic pressures have been used at room temperature to transform the crystallographic phase from P4mm to R3c for the compositions 0.7BiFeO3–0.3PbTiO3 and 0.65BiFeO3–0.35PbTiO3, as determined using in-situ neutron diffraction. Using Rietveld refinements, the resultant data showed that, for both compositions, a transformation from para- to G-type antiferromagnetic order accompanied the structural transition. The transformation occurred over the range 0.4–0.77 and 0.67–0.88 GPa for 0.7BiFeO3–0.3PbTiO3 and 0.65BiFeO3–0.35PbTiO3, respectively; at intermediate pressures, a mixture of P4mm and R3c phases were evident. These pressures are far lower than required to induce a phase transition in either the BiFeO3 or PbTiO3 end members. The driving force for this pressure induced first order phase transition is a significant difference in volume between the two phases, P4mm > R3c of 4%-5%, at ambient pressure. Upon removal of the pressure, 0.65BiFeO3–0.35PbTiO3 returned to the paramagnetic tetragonal state, whereas in 0.7BiFeO3–0.3PbTiO3 antiferromagnetic ordering persisted, and the structural phase remained rhombohedral. Using conventional laboratory x-ray diffraction with a hot-stage, the phase readily reverted back to a tetragonal phase, at temperatures between 100 and 310 °C for 0.7BiFeO3–0.3PbTiO3, far lower than the ferroelectric Curie point for this composition of 632 °C. To our knowledge, the reported pressure induced para- to antiferromagnetic transition is unique in the literature.
Heteroepitaxy between wurtzite and corundum materials
Authors: Hayashi Yuki , Banal Ryan G. , Funato Mitsuru , Kawakami Yoichi
Published: May 2013

Heteroepitaxy of wurtzite semiconductors on corundum substrates is widely used in modern optoelectronic devices, because both crystals belong to the same hexagonal close-packed system. However, the constituent atoms in the wurtzite structure align in an ideal hexagon within the (0001) plane, whereas those in the corundum structure are displaced due to empty octahedral sites. Herein, we demonstrate that this atomic arrangement mismatch at the interface generates low-angle grain boundaries in epilayers, and step bunching of corundum substrates with an even number of molecular layers can eliminate the boundaries. Furthermore, we propose that the weakened epitaxial relationship between epilayers and substrates also eliminates low-angle grain boundaries, which may be useful for practical applications.
Indeterminacy and instability in Petschek reconnection
Authors: Forbes Terry G. , Priest Eric R. , Seaton Daniel B. , Litvinenko Yuri E.
Published: May 2013

We explain two puzzling aspects of Petschek's model for fast reconnection. One is its failure to occur in plasma simulations with uniform resistivity. The other is its inability to provide anything more than an upper limit for the reconnection rate. We have found that previously published analytical solutions based on Petschek's model are structurally unstable if the electrical resistivity is uniform. The structural instability is associated with the presence of an essential singularity at the X-line that is unphysical. By requiring that such a singularity does not exist, we obtain a formula that predicts a specific rate of reconnection. For uniform resistivity, reconnection can only occur at the slow, Sweet-Parker rate. For nonuniform resistivity, reconnection can occur at a much faster rate provided that the resistivity profile is not too flat near the X-line. If this condition is satisfied, then the scale length of the nonuniformity determines the reconnection rate.
A deeper insight into the operation regime of all-polymeric electrochemical transistors
Authors: Demelas M. , Scavetta E. , Basiricò L. , Rogani R. , Bonfiglio A.
Published: May 2013

All-Organic Electrochemical Transistors (OECTs) realized by employing Poly(3,4-EthyleneDiOxyThiophene) doped with Poly(Styrene Sulfonate) as conductive polymer show a dependence of their behavior on the gate to channel area ratio. This peculiarity has been investigated and the working mechanism has been explained in view of the behavior of the ionic component of the device. In particular, taking into account the current theory of OECT behavior, we have focused our attention on the role of the gate, trying to clarify if these devices may be considered as working in Faradaic or capacitive regime.