bluuebunny/crossref_metadata_2025 huggingface dataset:
Photochemical Study of Chalconoid‐like Compounds: Synthesis of 4‐Flavanoids
Authors: Kamboj Ramesh C. , Kumar Dinesh , Berar Surinder , Sharma Geeta , Arora Rita
Published: December 2013

The photo‐irradiation of chalconoid‐like compounds; (2E,4E)‐1‐(2‐hydroxyaryl)‐4‐methyl‐5‐phenylpenta‐2,4‐dien‐1‐ones to 4‐flavanoids in solution phase has been described. The molecular scaffold of the probed substrates is responsive to intramolecular cyclization as well as cis‐trans isomerizations and photoproducts corresponding to both of reactions have been realized also. The formation of photoproducts has been explained on the basis of excited state intramolecular proton transfer that further depends upon the different substituents present on the phenolic moiety.
Suspension and optical properties of the crystalline lens in the eyes of basal vertebrates
Authors: Kröger Ronald H.H. , Gustafsson Ola S.E. , Tuminaite Inga
Published: December 2013

We have investigated the apparatus suspending the crystalline lens in the eyes of basal vertebrates. Data are presented for Holocephali (Chondrichthyes) and the actinopterygians Polypteriformes, Polyodontidae (Acipenseriformes), Lepisosteiformes, Amiiformes, and one teleost species, the banded archerfish (Toxotes jaculatrix). We also studied the optical properties of the lens in Polypteriformes, Lepisosteiformes, and the archerfish. Together with previously published results, our findings show that there are three basic types of lens suspension in vertebrates. These are i) a rotationally symmetric suspension (Petromyzontida, lampreys; Ceratodontiformes, lungfishes; Tetrapoda), ii) a suspension with a dorso‐ventral axis of symmetry and a ventral papilla (all Chondrichthyes and Acipenseriformes), and iii) an asymmetric suspension with a ventral muscle and a varying number of ligaments (all Actinopterygii except for Acipenseriformes). Large eyes with presumably high spatial resolution have evolved in all groups. Multifocal lenses creating well‐focused color images are also present in all groups studied. Stable and exact positioning of the lens, in many cases in combination with accommodative changes in lens position or shape, is achieved by all three types of lens suspension. It is somewhat surprising that lens suspensions are strikingly similar in Chondrichthyes and Acipenseriformes (Actinopterygii), while the suspension apparatus in Polypteriformes, usually being regarded as an actinopterygian group more basal than Acipenseriformes, are considerably more teleostean‐like. This study completes a series of investigations on lens suspensions in nontetrapod vertebrates, covering all major groups except for the rare and highly derived coelacanths. J. Morphol. 275:613–622, 2014. © 2013 Wiley Periodicals, Inc.
Mass spectrometry analysis of nitrotyrosine‐containing proteins
Authors: Zhan Xianquan , Wang Xiaowei , Desiderio Dominic M.
Published: December 2013

Oxidative stress plays important roles in a wide range of diseases such as cancer, inflammatory disease, neurodegenerative disorders, etc. Tyrosine nitration in a protein is a chemically stable oxidative modification, and a marker of oxidative injuries. Mass spectrometry (MS) is a key technique to identify nitrotyrosine‐containing proteins and nitrotyrosine sites in endogenous and synthetic nitroproteins and nitropeptides. However, in vivo nitrotyrosine‐containing proteins occur with extreme low‐abundance to severely challenge the use of MS to identify in vivo nitroproteins and nitrotyrosine sites. A preferential enrichment of nitroproteins and/or nitropeptides is necessary before MS analysis. Current enrichment methods include immuno‐affinity techniques, chemical derivation of the nitro group plus target isolations, followed with tandem mass spectrometry analysis. This article reviews the MS techniques and pertinent before‐MS enrichment techniques for the identification of nitrotyrosine‐containing proteins. This article reviews future trends in the field of nitroproteomics, including quantitative nitroproteomics, systems biological networks of nitroproteins, and structural biology study of tyrosine nitration to completely clarify the biological functions of tyrosine nitration. © 2013 Wiley Periodicals, Inc. Mass Spec Rev 34: 423–448, 2015.
Multivariate age‐dependent imperfect repair
Authors: Sheu Shey‐Huei , Griffith William S.
Published: December 2013

In this article we consider models of systems whose components have dependent life lengths with specific multivariate distributions. Upon failure, components are repaired. Two types of repair are distinguished. After perfect repair, a unit has the same life distribution as a new item. After imperfect repair, a unit has the life distribution of an item which is of the same age but has never failed. We study a model in which the mechanism for determining the nature of the repair is age dependent.
Testing guaranteed exponentiality
Authors: Shanmugam Ramalingam
Published: December 2013

Among distributions that are used in survival analysis, of interest to us here is the Guaranteed exponential (for details about the distribution, see Gross and Clark 7). In this article, we present a new approach to testing guaranteed exponentiality. Using engineering data on the number of load cycles until a crack appears in the titanium and steel sheet in aircraft, medical data on the number of weeks tumor patients survived, data on modulus of rupture, a measurement on the breaking strength of lumber, and original I.Q. data on 112 children attending kindergarten classes in San Jose and San Mateo Counties, CA, we illustrate our method. The first two data sets are known to follow exponential distribution, while the last data set is known to follow normal distribution. Our method confirms these and nonexponentiality for the third data set. A discussion on the merits and disadvantages of our approach is included. Based on simulation, a comparison is made between the power of our test and EDF test statisticA2. Our test has excellent power for many nonexponential alternatives.
Maternal obesity and risk of Down syndrome in the offspring
Authors: Hildebrand Eric , Källén Bengt , Josefsson Ann , Gottvall Tomas , Blomberg Marie
Published: December 2013

Objective

The objective of this article is to determine if maternal obesity is associated with an increased risk of Down syndrome in the offspring and whether the risk estimates for trisomy 21 based on combined screening is affected by maternal body mass index (BMI).

Methods

Study group I consisted of a nationwide cohort of 1 568 604 women giving birth; outcome was infants born with Down syndrome [Correction made here after initial online publication.]. Adjustment was made for maternal age. Study group II consisted of 10 224 women undergoing 1st trimester combined screening. Outcome was risk assessment for Down syndrome. All women were divided into six BMI groups, and outcomes were evaluated over the BMI strata with BMI 18.5 to 24.9 as reference and correcting for maternal age.

Results

Obese women had an increased risk for giving birth to an infant with Down syndrome compared with normal‐weight women, BMI 30 to 34.9 odds ratio (OR) 1.31 [95% confidence interval (CI) 1.10–1.55], BMI 35 to 39.9 OR 1.12 (95% CI 0.82–1.53), BMI ≥ 40 OR 1.56 (95% CI 1.00–2.43). The observed and the expected numbers of women with a risk of Down syndrome >1/300 based on 1st trimester combined screen and maternal age were similar in each BMI group.

Conclusion

Maternal obesity seems to increase the risk for Down syndrome births. The risk estimate for Down syndrome with 1st trimester combined screening is unaffected by BMI. © 2013 John Wiley & Sons, Ltd.
Polymer physics inspired approaches for the study of the mechanical properties of amyloid fibrils
Authors: Volpatti Lisa R. , Knowles Tuomas P. J.
Published: December 2013

Amyloid structures constitute a class of highly ordered nanomaterials formed by insoluble protein aggregates. These aggregates are characterized by a cross‐β structural motif in which β‐sheets are oriented perpendicular to the fibril axis and bound together by a dense hydrogen bonding network. Although they have been associated with several neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases, amyloid fibrils have also been found in many physiologically beneficial roles, for instance in adhesives and hormone storage. Inspired by this natural occurrence of functional amyloid, the hierarchal self‐assembly of these structures has recently been used to develop artificial biomaterials for applications in medicine and nanotechnology. In order to realize the full potential of amyloids as functional materials, it is important to understand their fundamental mechanical properties. This review explores a range of experimental strategies to determine the mechanical properties of amyloid fibrils and discusses the results in the context of polymer physics concepts. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys.2014,52, 281–292
Antitubercular and Antibacterial Activity of Quinonoid Natural Products Against Multi‐Drug Resistant Clinical Isolates
Authors: Dey Diganta , Ray Ratnamala , Hazra Banasri
Published: December 2013

Multi‐drug resistant Mycobacterium tuberculosis and other bacterial pathogens represent a major threat to human health. In view of the critical need to augment the current drug regime, we have investigated therapeutic potential of five quinonoids, viz. emodin, diospyrin, plumbagin, menadione and thymoquinone, derived from natural products. The antimicrobial activity of quinonoids was evaluated against a broad panel of multi‐drug and extensively drug‐resistant tuberculosis (M/XDR‐TB) strains, rapid growing mycobacteria and other bacterial isolates, some of which were producers of β‐lactamase, Extended‐spectrum β‐lactamase (ESBL), AmpC β‐lactamase, metallo‐beta‐lactamase (MBL) enzymes, as well as their drug‐sensitive ATCC counterparts. All the tested quinones exhibited antimycobacterial and broad spectrum antibacterial activity, particularly against M. tuberculosis (lowest MIC 0.25 µg/mL) and Gram‐positive bacteria (lowest MIC <4 µg/mL) of clinical origin. The order of antitubercular activity of the tested quinonoids was plumbagin > emodin ~ menadione ~ thymoquinone > diospyrin, whereas their antibacterial efficacy was plumbagin > menadione ~ thymoquinone > diospyrin > emodin. Furthermore, this is the first evaluation performed on these quinonoids against a broad panel of drug‐resistant and drug‐sensitive clinical isolates, to the best of our knowledge. Copyright © 2013 John Wiley & Sons, Ltd.
Historical Published Maintenance Data: What Can It Tell Us About Reliability Modelling?
Authors: McCollin Chris , Coleman Shirley
Published: December 2013

The paper discusses physical assumptions versus statistical assumptions illustrated by some reliability data, which if modelled ignoring physical assumptions (which are more important) gives incorrect results. The importance of physical assumptions can be extended to each stage of systems and service to improve the modelling being done (or that should be done). Explanatory physical information regarding systems is available within reliability data. It just has to be searched for. Four typical data sets are analysed in detail in the paper. In these analyses, an attempt has been made to convert operational time to ‘failure’ to calendar time to maintenance event. There are many other data sets that this straightforward methodology can be applied to. Previous research has developed methods for analysing the operational time of individual equipment but a more comprehensive approach is required to model the whole maintenance system taking into account both the planned and unplanned events. Copyright © 2013 John Wiley & Sons, Ltd.
ALPPS for Patients with Colorectal Liver Metastases: Effective Liver Hypertrophy, but Early Tumor Recurrence
Authors: Oldhafer Karl J. , Donati Marcello , Jenner Robert M. , Stang Axel , Stavrou Gregor A.
Published: December 2013

Background

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a promising method to increase resectability rates of liver tumors. Little has been published about oncological results so far. This report describes clinical evidence regarding a possible effect of ALPPS on tumor recurrence.

Methods

Ten ALPPS procedures were performed for otherwise non‐resectable colorectal liver metastases. Seven of these ten patients had a follow‐up of at least 3 months and were analyzed for tumor recurrence.

Results

Six of these seven patients had tumor recurrence to the liver. Three of seven patients presented with lung metastases, occurring earlier than liver metastases in two of three cases. One patient with a follow‐up of 3 months had no visible recurrent disease, but increasing carcinoembryonic antigen levels.

Conclusions

The patient group operable only through ALPPS is at high risk for recurrence and early tumor progression. Still, this new method is the only chance for an oncological treatment strategy including a surgical approach and possibly better outcome.
Short-term functional outcome and premorbid adjustment in clinical high-risk patients. Results of the EPOS project
Authors: Salokangas R.K.R. , Heinimaa M. , From T. , Löyttyniemi E. , Ilonen T. , Luutonen S. , Hietala J. , Svirskis T. , von Reventlow H.G. , Juckel G. , Linszen D. , Dingemans P. , Birchwood M. , Patterson P. , Schultze-Lutter F. , Ruhrmann S. , Klosterkötter J.
Published: December 2013

Purpose

In patients with schizophrenia, premorbid psychosocial adjustment is an important predictor of functional outcome. We studied functional outcome in young clinical high-risk (CHR) patients and how this was predicted by their childhood to adolescence premorbid adjustment.

Methods

In all, 245 young help-seeking CHR patients were assessed with the Premorbid Adjustment Scale, the Structured Interview for Prodromal Syndromes (SIPS) and the Schizophrenia Proneness Instrument (SPI-A). The SIPS assesses positive, negative, disorganised, general symptoms, and the Global Assessment of Functioning (GAF), the SPI-A self-experienced basic symptoms; they were carried out at baseline, at 9-month and 18-month follow-up. Transitions to psychosis were identified. In the hierarchical linear model, associations between premorbid adjustment, background data, symptoms, transitions to psychosis and GAF scores were analysed.

Results

During the 18-month follow-up, GAF scores improved significantly, and the proportion of patients with poor functioning decreased from 74% to 37%. Poor premorbid adjustment, single marital status, poor work status, and symptoms were associated with low baseline GAF scores. Low GAF scores were predicted by poor premorbid adjustment, negative, positive and basic symptoms, and poor baseline work status. The association between premorbid adjustment and follow-up GAF scores remained significant, even when baseline GAF and transition to psychosis were included in the model.

Conclusion

A great majority of help-seeking CHR patients suffer from deficits in their functioning. In CHR patients, premorbid psychosocial adjustment, baseline positive, negative, basic symptoms and poor working/schooling situation predict poor short-term functional outcome. These aspects should be taken into account when acute intervention and long-term rehabilitation for improving outcome in CHR patients are carried out.
Conscientious objection or fear of social stigma and unawareness of ethical obligations
Authors: Faúndes Anibal , Duarte Graciana Alves , Osis Maria José Duarte
Published: December 2013

Conscientious objection is a legitimate right of physicians to reject the practice of actions that violate their ethical or moral principles. The application of that principle is being used in many countries as a justification to deny safe abortion care to women who have the legal right to have access to safe termination of pregnancy. The problem is that, often, this concept is abused by physicians who camouflage under the guise of conscientious objection their fear of experiencing discrimination and social stigma if they perform legal abortions. These colleagues seem to ignore the ethical principle that the primary conscientious duty of OB/GYNs is—at all times—to treat, or provide benefit and prevent harm to, the patients for whose care they are responsible. Any conscientious objection to treating a patient is secondary to this primary duty. One of the jobs of the FIGO Working Group for the Prevention of Unsafe Abortion is to change this paradigm and make our colleagues proud of providing legal abortion services that protect women's life and health, and concerned about disrespecting the human rights of women and professional ethical principles.
State-Building and Tax Regimes in Central America. By Aaron Schneider. New York: Cambridge University Press, 2012. 260p. $90.00.
Authors: Easter Gerald M.
Published: December 2013

After a long period waiting in the wings, the Fisc (the state treasury, or the larger system of public finance) has returned to center stage in comparative politics. During this time, fiscal sociologist Joseph Schumpeter was more likely to be cited for his “creative destruction” thesis, than for his “crisis of the tax state” analysis. While the “return to the state” dates back to the late 1970s, it still took another decade before taxation became a monograph headliner, with influential works by Margaret Levi (Of Rule and Revenue, 1988), Charles Tilly (Coercion, Capital and European States: AD 990–1992, 1992) and Sven Steinmo (Taxation and Democracy: Swedish, British and American Approaches to Financing the Modern State, 1996). Since then, tax policy and extractive capacity have increasingly come to be recognized by comparativists as central to state-building projects, thus confirming Edmund Burke's old adage that “the revenue of the state is the state.” As part of this fiscal revival in comparative politics, Aaron Schneider has rightfully earned the status as leading expert on Central America with his new book, State-Building and Tax Regimes in Central America.
Modification of coordination networks through a photoinduced charge transfer process
Authors: Easun Timothy L. , Jia Junhua , Reade Thomas J. , Sun Xue-Zhong , Davies E. Stephen , Blake Alexander J. , George Michael W. , Champness Neil R.
Published: December 2013

A photoinduced charge transfer process within the framework of a coordination network leads to an irreversible process that facilitates writing on crystals.
Nucleotide/Tb3+ coordination polymer as a luminescent nanosensor: synthesis and sensing of iron(ii) in human serum
Authors: Liu Baoxia , Sun Chunlei , Chen Yang
Published: December 2013

Lanthanide ions and nucleotides were used to design and prepare a kind of responsive luminescent nanosensor for iron ions through a self-assembly process.
A new look at the photodissociation of methyl iodide at 193 nm
Authors: Xu Hong , Pratt S. T.
Published: December 2013

A new measurement of the photodissociation of CH3I at 193 nm is reported in which we use a combination of vacuum ultraviolet photoionization and velocity map ion imaging. The iodine photofragments are probed by single-photon ionization at photon energies above and below the photoionization threshold of I(2P3/2). The relative I(2P3/2) and I*(2P1/2) photoionization cross sections are determined at these wavelengths by using the known branching fractions for the photodissociation at 266 nm. Velocity map ion images indicate that the branching fraction for I(2P3/2) atoms is non-zero, and yield a value of 0.07 ± 0.01. Interestingly, the translational energy distribution extracted from the image shows that the translational energy of the I(2P3/2) fragments is significantly smaller than that of the I*(2P1/2) atoms. This observation indicates the internal rotational/vibrational energy of the CH3 co-fragment is very high in the I(2P3/2) channel. The results can be interpreted in a manner consistent with the previous measurements, and provide a more complete picture of the dissociation dynamics of this prototypical molecule.
A mode converter to generate a Gaussian-like mode for injection into the VENUS electron cyclotron resonance ion source
Authors: Lyneis C. , Benitez J. , Hodgkinson A. , Plaum B. , Strohmeier M. , Thuillier T. , Todd D.
Published: December 2013

A number of superconducting electron cyclotron resonance (ECR) ion sources use gyrotrons at either 24 or 28 GHz for ECR heating. In these systems, the microwave power is launched into the plasma using the TE01 circular waveguide mode. This is fundamentally different and may be less efficient than the typical rectangular, linearly polarized TE10 mode used for launching waves at lower frequencies. To improve the 28 GHz microwave coupling in VENUS, a TE01-HE11 mode conversion system has been built to test launching HE11 microwave power into the plasma chamber. The HE11 mode is a quasi-Gaussian, linearly polarized mode, which should couple strongly to the plasma electrons. The mode conversion is done in two steps. First, a 0.66 m long “snake” converts the TE01 mode to the TE11 mode. Second, a corrugated circular waveguide excites the HE11 mode, which is launched directly into the plasma chamber. The design concept draws on the development of similar devices used in tokamaks and stellerators. The first tests of the new coupling system are described below.
A minimally-resolved immersed boundary model for reaction-diffusion problems
Authors: Pal Singh Bhalla Amneet , Griffith Boyce E. , Patankar Neelesh A. , Donev Aleksandar
Published: December 2013

We develop an immersed boundary approach to modeling reaction-diffusion processes in dispersions of reactive spherical particles, from the diffusion-limited to the reaction-limited setting. We represent each reactive particle with a minimally-resolved “blob” using many fewer degrees of freedom per particle than standard discretization approaches. More complicated or more highly resolved particle shapes can be built out of a collection of reactive blobs. We demonstrate numerically that the blob model can provide an accurate representation at low to moderate packing densities of the reactive particles, at a cost not much larger than solving a Poisson equation in the same domain. Unlike multipole expansion methods, our method does not require analytically computed Green's functions, but rather, computes regularized discrete Green's functions on the fly by using a standard grid-based discretization of the Poisson equation. This allows for great flexibility in implementing different boundary conditions, coupling to fluid flow or thermal transport, and the inclusion of other effects such as temporal evolution and even nonlinearities. We develop multigrid-based preconditioners for solving the linear systems that arise when using implicit temporal discretizations or studying steady states. In the diffusion-limited case the resulting linear system is a saddle-point problem, the efficient solution of which remains a challenge for suspensions of many particles. We validate our method by comparing to published results on reaction-diffusion in ordered and disordered suspensions of reactive spheres.
Real-time observation of the interface between SiC and a liquid alloy and its application to the dissolution behavior of SiC at 1573 K
Authors: Kawanishi Sakiko , Yoshikawa Takeshi , Morita Kazuki , Kusunoki Kazuhiko , Kamei Kazuhito , Suzuki Hiroshi , Sakamoto Hidemitsu
Published: December 2013

Real-time observation of the high temperature interface between silicon carbide (SiC) and liquid alloy is indispensable to optimize the conditions for producing high quality SiC crystals by the solution growth method. In this work, real-time observation of the interface was established by using the interference observation to measure the height profile of the interface. The temperature dependence of the refractive index of 4H-SiC was measured up to 1773 K. The height measurement was then carried out for the SiC/alloy interface at 1573 K. From interference observation, bunched step heights of less than 10 nm were measured. The developed technique was applied for the real-time observation of dissolution behavior of SiC into molten Fe-Si alloy at 1573 K. The dissolution kinetics was discussed in terms of carbon mass transfer in the solution and interfacial reaction.
Vibration responses of h-BN sheet to charge doping and external strain
Authors: Yang Wei , Yang Yu , Zheng Fawei , Zhang Ping
Published: December 2013

Based on density functional theory and density functional perturbation theory calculations, we systematically investigate the vibration responses of h-BN sheet to charge doping and external strains. It is found that under hole doping, the phonon frequencies of the ZO and TO branches at different wave vector q shift linearly with different slopes. Under electron doping, although the phonon frequencies shift irregularly, the shifting values are different at different phonon wave vectors. Interestingly, we find that external strain can restrain the irregular vibration responses of h-BN sheet to electron doping. The critical factor is revealed to be the relative position of the nearly free electron and boron pz states of h-BN sheet. Under external strains, the vibration responses of h-BN sheet are also found to be highly dependent on the phonon branches. Different vibration modes at different q points are revealed to be responsible for the vibration responses of h-BN sheet to charge doping and external strain. Our results point out a new way to detect the doping or strain status of h-BN sheet by measuring the vibration frequencies at different wave vector.
Half-metallicity and stability of the rock salt BaC and SrC (111) surfaces: A density functional study
Authors: Tabatabaeifar A. H. , Davatolhagh S. , Foroughpour M.
Published: December 2013

The electronic structure and magnetic properties of relaxed (111) surfaces of the alkaline-earth monocarbides BaC and SrC in the stable rock salt structure, are calculated on the basis of first principle density functional theory within the framework of self-consistent field plane wave pseudo-potential method, using the generalized gradient approximation for the exchange-correlation functional. The results of this study reveal that the C-terminated (111) surfaces retain the bulk half-metallic property in both BaC and SrC. The half-metallicity of the C-terminated BaC surface is found to be more robust compared to the bulk BaC due to the larger half-metallic energy gap. In contrast, the half-metallic energy gap of the C-terminated SrC surface is found to be smaller than that of the bulk. The Ba-terminated surface of BaC and the Sr-terminated surface of SrC, however, lose their bulk half-metallicity due to the formation of surface states in the majority spin band gap. The calculations also show that the atomic magnetic moments at the half-metallic C-terminated surfaces in both BaC and SrC increase considerably with respect to the corresponding bulk values, which is explained in terms of an increase in the number of unpaired 2p electrons of the carbon atom at the surface. We also discuss the stability of the surfaces via the calculated bulk formation energies. The bulk formation energies for both BaC and SrC in the rock salt structure are found to be positive, which indicate that the surfaces are not stable at normal pressure and temperature conditions, and non-equilibrium growth techniques may be required for the realization of BaC and SrC thin films.
Scanning-free grazing emission x-ray fluorescence by means of an angular dispersive arrangement with a two-dimensional position-sensitive area detector
Authors: Kayser Y. , Szlachetko J. , Sà J.
Published: December 2013

We report on the application of a two-dimensional position-sensitive area detector towards grazing emission x-ray fluorescence (GEXRF) spectroscopy. GEXRF allows for surface-sensitive studies with nanometer-scale accuracy in the depth direction by measuring the intensity variation of an x-ray fluorescence line with the grazing emission angle. The presented experimental setup is based on a fixed sample-detector arrangement and does not require any moving components. We show that the dispersion of the grazing emission angle along a position-sensitive detector allows to acquire with an excellent angular resolution a full GEXRF profile in a single measurement. Moreover, the use of a two-dimensional detector allows to perform experiments with an increased solid angle of detection per emission angle. This results in combination with the nonsequential and simultaneous acquisition of the GEXRF profiles of different emission lines in considerably reduced acquisition times. The realization, the demands, and the main characteristics of the scanning-free GEXRF setup will be presented. A few experimental examples will serve to illustrate the analytical possibilities offered by the presented setup.
Reliable self-powered highly spectrum-selective ZnO ultraviolet photodetectors
Authors: Shen H. , Shan C. X. , Li B. H. , Xuan B. , Shen D. Z.
Published: December 2013

Ultraviolet photodetectors (PDs) have been fabricated from p-ZnO:(Li,N)/n-ZnO structures in this Letter. The PDs can operate without any external power supply and show response only to a very narrow spectrum range. The self-power character of the devices is due to the built-in electric field in the p-n junctions that can separate the photogenerated electrons and holes while the high spectrum-selectivity has been attributed to the filter effect of the neutral region in the ZnO:(Li,N) layer. The performance of the self-powered highly spectrum-selective PDs degrades little after five months, indicating their good reliability.
Photoacoustic elastic bending in thin film—Substrate system
Authors: Todorović D. M. , Rabasović M. D. , Markushev D. D.
Published: December 2013

Theoretical model for optically excited two-layer elastic plate, which includes plasmaelastic, thermoelastic, and thermodiffusion mechanisms, is given in order to study the dependence of the photoacoustic (PA) elastic bending signal on the optical, thermal, and elastic properties of thin film—substrate system. Thin film-semiconductor sample (in our case Silicon) is modeled by simultaneous analysis of the plasma, thermal, and elastic wave equations. Multireflection effects in thin film are included in theoretical model and analyzed. Relations for the amplitude and phase of electronic and thermal elastic bending in the optically excited two-layer mechanically-supported circular plate are derived. Theoretical analysis of the thermodiffusion, plasmaelastic, and thermoelastic effects in a sample-gas-microphone photoacoustic detection configuration is given. Two normalization procedures of the photoacoustic elastic bending signal in function of the modulation frequency of the optical excitation are established. Given theoretical model can be used for various photoacoustic detection configurations, for example, in the study of optical, thermal, and elastic properties of the dielectric-semiconductor or metal-semiconductor structure, etc., Theoretical analysis shows that it is possible to develop new noncontact and nondestructive experimental method—PA elastic bending method for thin film study, with possibility to obtain the optical, thermal, and elastic parameters of the film thinner than 1 μm.
Communication: A reduced-space algorithm for the solution of the complex linear response equations used in coupled cluster damped response theory
Authors: Kauczor Joanna , Norman Patrick , Christiansen Ove , Coriani Sonia
Published: December 2013

We present a reduced-space algorithm for solving the complex (damped) linear response equations required to compute the complex linear response function for the hierarchy of methods: coupled cluster singles, coupled cluster singles and iterative approximate doubles, and coupled cluster singles and doubles. The solver is the keystone element for the development of damped coupled cluster response methods for linear and nonlinear effects in resonant frequency regions.
Detailed energy distributions in laser-produced plasmas of solid gold and foam gold planar targets
Authors: Dong Yunsong , Zhang Lu , Yang Jiamin , Shang Wanli
Published: December 2013

Foam gold was proposed to increase the laser to x-ray conversion efficiency due to its important applications. To understand the mechanism of x-ray enhancement, the detailed energy distributions and plasma profiles for laser-irradiated solid gold and foam gold targets were studied comparatively by hydrodynamic simulations using the code Multi-1D. It is confirmed that the radiation heat wave is subsonic for the normal solid gold target, while supersonic for the foam gold target. The shock wave, which is behind the supersonic radiation heat wave for the foam gold target, generates a plasma temperature gradient with high temperature near the shock wave front to produce an additional net outward radiation for enhancement of the x-ray emission. Much larger inward plasma velocity is also driven by the shock wave as an initial plasma velocity for the laser deposition and electron thermal conduct zone, which decreases the expanding plasma kinetic energy loss and helps to increase the x-ray radiation.
Solution-based silk fibroin dielectric in n-type C60 organic field-effect transistors: Mobility enhancement by the pentacene interlayer
Authors: Tsai Li-Shiuan , Hwang Jenn-Chang , Lee Chun-Yi , Lin Yi-Ting , Tsai Cheng-Lun , Chang Ting-Hao , Chueh Yu-Lun , Meng Hsin-Fei
Published: December 2013

A pentacene interlayer of 2 nm thick is inserted between fullerene (C60) and the solution-based silk fibroin dielectric in C60 organic field-effect transistors (OFETs). The pentacene interlayer assists to improve crystal quality of the C60 layer, leading to the increase of field-effect mobility (μFE) from 0.014 to 1 cm2 V−1 s−1 in vacuum. The μFE value of the C60 OFET is further enhanced to 10 cm2 V−1 s−1 when the OFET is exposed to air in a relative humidity of 55%. Generation of mobile and immobile charged ions in solution-based silk fibroin in air ambient is proposed.
Growth of CdTe thin films on graphene by close-spaced sublimation method
Authors: Jung Younghun , Yang Gwangseok , Chun Seungju , Kim Donghwan , Kim Jihyun
Published: December 2013

CdTe thin films grown on bi-layer graphene were demonstrated by using the close-spaced sublimation method, where CdTe was selectively grown on the graphene. The density of the CdTe domains was increased with increasing the number of the defective sites in the graphene, which was controlled by the duration of UV exposure. The CdTe growth rate on the bi-layer graphene electrodes was 400 nm/min with a bandgap energy of 1.45–1.49 eV. Scanning electron microscopy, micro-Raman spectroscopy, micro-photoluminescence, and X-ray diffraction technique were used to confirm the high quality of the CdTe thin films grown on the graphene electrodes.
Magnetic edge states in Aharonov-Bohm graphene quantum rings
Authors: Farghadan R. , Saffarzadeh A. , Heidari Semiromi E.
Published: December 2013

The effect of electron-electron interaction on the electronic structure of Aharonov-Bohm (AB) graphene quantum rings (GQRs) is explored theoretically using the single-band tight-binding Hamiltonian and the mean-field Hubbard model. The electronic states and magnetic properties of hexagonal, triangular, and circular GQRs with different sizes and zigzag edge terminations are studied. The results show that, although the AB oscillations in the all types of nanoring are affected by the interaction, the spin splitting in the AB oscillations strongly depends on the geometry and the size of graphene nanorings. We found that the total spin of hexagonal and circular rings is zero and therefore, no spin splitting can be observed in the AB oscillations. However, the non-zero magnetization of the triangular rings breaks the degeneracy between spin-up and spin-down electrons, which produces spin-polarized AB oscillations.
Photoluminescence properties and energy levels of RE (RE = Pr, Sm, Er, Tm) in layered-CaZnOS oxysulfide
Authors: Zhang Zhi-Jun , Feng Ang , Chen Xiang-Yang , Zhao Jing-Tai
Published: December 2013

RE3+ (RE = Pr, Sm, Er, Tm)-activated CaZnOS samples were prepared by a solid-state reaction method at high temperature, and their photoluminescence properties were investigated. Doping with RE3+ (RE = Pr, Sm, Er, Tm) into layered-CaZnOS resulted in typical RE3+ (RE = Pr, Sm, Er, Tm) f-f line absorptions and emissions, as well as the charge transfer band of Sm3+ at about 3.3 eV. The energy level scheme containing the position of the 4f and 5d levels of all divalent and trivalent lanthanide ions with respect to the valence and conduction bands of CaZnOS has been constructed based on the new data presented in this work, together with the data from literature on Ce3+ and Eu2+ doping in CaZnOS. The detailed energy level scheme provides a platform for interpreting the optical spectra and could be used to comment on the valence stability of the lanthanide ions in CaZnOS.
Controlled deposition of sulphur-containing semiconductor and dielectric nano-structured films on metals in SF6 ion-ion plasma
Authors: Rafalskyi Dmytro , Bredin Jérôme , Aanesland Ane
Published: December 2013

In the present paper, the deposition processes and formation of films in SF6 ion-ion plasma, with positive and negative ion flows accelerated to the surface, are investigated. The PEGASES (acronym for Plasma Propulsion with Electronegative GASES) source is used as an ion-ion plasma source capable of generating almost ideal ion-ion plasma with negative ion to electron density ratio more than 2500. It is shown that film deposition in SF6 ion-ion plasma is very sensitive to the polarity of the incoming ions. The effect is observed for Cu, W, and Pt materials. The films formed on Cu electrodes during negative and positive ion assisted deposition were analyzed. Scanning electron microscope analysis has shown that both positive and negative ion fluxes influence the copper surface and leads to film formation, but with different structures of the surface: the low-energy positive ion bombardment causes the formation of a nano-pored film transparent for ions, while the negative ion bombardment leads to a continuous smooth insulating film. The transversal size of the pores in the porous film varies in the range 50–500 nm, and further analysis of the film has shown that the film forms a diode together with the substrate preventing positive charge drain, and positive ions are neutralized by passing through the nano-pores. The film obtained with the negative ion bombardment has an insulating surface, but probably with a multi-layer structure: destroying the top surface layer allows to measure similar “diode” IV-characteristics as for the nano-pored film case. Basing on results, practical conclusions for the probes and electrodes cleaning in ion-ion SF6 plasmas have been made. Different applications are proposed for the discovered features of the controlled deposition from ion-ion plasmas, from Li-sulphur rechargeable batteries manufacturing and nanofluidics issues to the applications for microelectronics, including low-k materials formation.
Quantitative hard x-ray phase contrast imaging of micropipes in SiC
Authors: Kohn V. G. , Argunova T. S. , Je J. H.
Published: December 2013

Peculiarities of quantitative hard x-ray phase contrast imaging of micropipes in SiC are discussed. The micropipe is assumed as a hollow cylinder with an elliptical cross section. The major and minor diameters can be restored using the least square fitting procedure by comparing the experimental data, i.e. the profile across the micropipe axis, with those calculated based on phase contrast theory. It is shown that one projection image gives an information which does not allow a complete determination of the elliptical cross section, if an orientation of micropipe is not known. Another problem is a weak accuracy in estimating the diameters, partly because of using pink synchrotron radiation, which is necessary because a monochromatic beam intensity is not sufficient to reveal the weak contrast from a very small object. The general problems of accuracy in estimating the two diameters using the least square procedure are discussed. Two experimental examples are considered to demonstrate small as well as modest accuracies in estimating the diameters.
TGF-β directs trafficking of the epithelial sodium channel ENaC which has implications for ion and fluid transport in acute lung injury
Authors: Peters Dorothea M. , Vadász István , Wujak Łukasz , Wygrecka Małgorzata , Olschewski Andrea , Becker Christin , Herold Susanne , Papp Rita , Mayer Konstantin , Rummel Sebastian , Brandes Ralph P. , Günther Andreas , Waldegger Siegfried , Eickelberg Oliver , Seeger Werner , Morty Rory E.
Published: December 2013

Significance

The acute respiratory distress syndrome (ARDS) is a devasting clinical problem with high mortality, no drug therapy, and poorly understood pathogenesis. The hallmark of ARDS is persistent pulmonary edema, attributable in part to impaired Na
+
and fluid transport across the alveolo-capillary barrier, undertaken by the epithelial sodium channel (ENaC). We describe a unique signaling pathway driven by TGF-β, which acutely dysregulates ENaC trafficking, blocking alveolar Na
+
transport and edema resolution. This pathway represents a unique pathomechanism in ARDS, highlights potential “druggable” targets, and may represent a physiological means of acutely regulating ENaC in lungs and other organs.
Stepwise artificial evolution of a plant disease resistance gene
Authors: Harris C. Jake , Slootweg Erik J. , Goverse Aska , Baulcombe David C.
Published: December 2013

Significance

Plant nucleotide-binding leucine-rich repeat (NB-LRR) proteins are responsible for detecting potential pathogens and triggering a defense response. However, disease resistance can also involve a cost. Here we show that the trailing necrosis cost associated with a broad-recognition version of the NB-LRR protein, Rx, can be overcome by selecting for mutations that increase the sensitivity of the NB-LRR protein. Using homology modeling, we predict that these mutations are colocalized to the ATP/ADP nucleotide-binding pocket, which is thought to control the switch between “active” and “inactive” states. These results suggest that a stepwise approach to coordinating recognition and response could be used to design improved NB-LRRs for use in agriculture.
Reproducible copy number variation patterns among single circulating tumor cells of lung cancer patients
Authors: Ni Xiaohui , Zhuo Minglei , Su Zhe , Duan Jianchun , Gao Yan , Wang Zhijie , Zong Chenghang , Bai Hua , Chapman Alec R. , Zhao Jun , Xu Liya , An Tongtong , Ma Qi , Wang Yuyan , Wu Meina , Sun Yu , Wang Shuhang , Li Zhenxiang , Yang Xiaodan , Yong Jun , Su Xiao-Dong , Lu Youyong , Bai Fan , Xie X. Sunney , Wang Jie
Published: December 2013

Significance

In a few milliliters of blood from a cancer patient, one can isolate a few circulating tumor cells (CTCs). Originating from the primary tumor, CTCs seed metastases, which account for the majority of cancer-related deaths. We demonstrate the analyses of the whole genome of single CTCs, which are highly needed for personalized treatment. We discovered that copy number variations (CNVs), one of the major genomic variations, are specific to cancer types, reproducible from cell to cell, and even from patient to patient. We hypothesize that CNVs at certain genomic loci are selected for and lead to metastasis. Our work shows the prospect of noninvasive CTC-based cancer diagnostics.
Composite ideophone-gesture utterances in the Ashéninka Perené ‘community of practice’, an Amazonian Arawak society from Central-Eastern Peru
Authors: Mihas Elena
Published: December 2013

Based on extensive fieldwork in Peru among Ashéninka Perené Arawaks, this study is a preliminary report on ideophone-gesture composites, with special focus on the meaning and functions of ideophone-gesture couplings within participatory learning frameworks. In expert-novice learning environments, ideophone-gesture composites appear to carry a unique cognitive-communicative load by forming scaffolding knowledge structures on the basis of the conventionalized ideophone-gesture inventories. The data are illustrative of Streeck’s (2009) vision of the hands’ involvement in meaning-making, i.e., that some of the ways in which depictive gestures evoke the world ascend from a basic set of everyday activities of hands in the world, within particular ecological and cultural settings.
The prosody of formulaic expression in the IBM/Lancaster Spoken English Corpus
Authors: Lin Phoebe M.S.
Published: December 2013

This article examines the distribution of the nucleus around selected formulaic expressions in the IBM/Lancaster Spoken English Corpus (SEC). The study reveals the presence of a positional bias such that formulaic expressions found at the end of intonation units are more likely to receive the nucleus than those found at the beginning. Amongst the formulaic expressions located at the end of intonation units, 70 percent have the nucleus assigned to the last lexical word of the expressions. For the remaining cases, the obligatory nuclei are found either on the lexical words immediately preceding the expressions or on the first words, the degree words or the flexible slots within the expressions. The study shows how prosodically annotated corpora may facilitate research on the prosody of formulaic expressions. At the same time, it also raises awareness of the issues confronting this new research avenue.
“People, Places, and Things:” Network Factors Matter in the Experiences of Mental Health Court Participants
Authors: Canada Kelli
Published: December 2013

Mental health courts (MHC) are expanding nationally but the evidence base involves substantial gaps in research. Although positive outcomes are associated with MHC participation, it is unclear as to what factors contribute to outcomes. The current study addresses gaps in research by exploring the experiences of MHC participants and associations between network factors and treatment adherence from consumers participating in two MHCs (N = 80). A mixed method design drawing from multiple data sources is utilized. Study results suggest network factors are significantly associated with treatment adherence and play an important role in recovery. Results have implications for social work practice and research.
Increasing Alternative Sentencing in the Juvenile Justice System Through a Partnership Between Public Defenders and Social Workers
Authors: GEURIN LYNN , Otis Melanie D. , Royse David
Published: December 2013

This study evaluated the effectiveness of a partnership between public defender attorneys and the Alternative Sentencing Social Work Field Education Program. An outcome was to increase alternative sentences that match the rehabilitative needs of juveniles in court. Sentencing outcomes of youth receiving the social work program (n = 116) were compared to youth receiving conventional public defender representation (n = 94). A logistical regression analysis found that juveniles represented by attorneys with social workers were nearly three times more likely (odds ratio = 2.72) to receive alternative sentences than those without social workers when controlling for prior record and charge severity.