bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photoinduced current in molecular conduction junctions with semiconductor contacts
Authors: Fainberg Boris , Seideman Tamar 
Published: October 2012

AbstractWe propose a new approach to coherent control of transport via molecular junctions, which bypasses several of the hurdles to experimental realization of optically manipulated nanoelectronics noted in the previous literature. The method is based on the application of intrinsic semiconductor contacts and optical frequencies below the semiconductor bandgap. It relies on a simple and general concept, namely the controllable photonic replication of molecular levels through the dipole driving the molecular bridge by an electromagnetic field. We predict the effect of coherent destruction of induced tunneling that extends the certain effect of coherent destruction of tunneling. Our results illustrate the potential of semiconductor contacts in coherent control of photocurrent.
Study of the low‐temperature properties of multiferroic YbMnO3 and YbMn0.7Ga0.3O3 single crystals
Authors: Abramov N. , Lofland S. , Mukovskii Ya. 
Published: October 2012

AbstractThe specific heat, magnetization, and magnetocapacitance of YbMnO3 and YbMn0.7Ga0.3O3 multiferroic single crystal manganites were measured in magnetic field. From the specific heat data it was stated that the effect of dilution of Mn by non‐magnetic Ga3+ ions led to reduced Mn magnetic interactions and suppressed the magnetic ordering of Yb in both the 2a and 4b positions. Combining the results of all measurements, the magnetic‐field–temperature phase diagram YbMnO3 was drawn, and the types of the Yb magnetic ordering in both positions were determined.
Real‐time manipulation of ZnO nanowires on a flat surface employed for tribological measurements: Experimental methods and modeling
Authors: Dorogin Leonid M. , Vlassov Sergei , Polyakov Boris , Antsov Mikk , Lõhmus Rünno , Kink Ilmar , Romanov Alexey E. 
Published: October 2012

AbstractElastic and tribological properties of zinc oxide nanowires (NWs) on Si wafer and highly oriented pyrolytic graphite (HOPG) are experimentally investigated and theoretically interpreted. Measurements are performed inside a scanning electron microscope (SEM) using real‐time manipulation technique that enables two possible ways of data registration: “external” force registration with quartz tuning fork (QTF) based sensor and “internal” force registration utilizing in situ observed elastic deformation of NWs. Young modulus is determined by loading half‐suspended NW at its free end and then employed for the following tribological experiments. Maximal static friction force is estimated when NW is being pushed at one end and switches from partial to complete motion upon overcoming static friction. Kinetic friction is extracted from the profile of the NW being uniformly dragged at the midpoint. After being brought to rest after the manipulations, the NW causes redistribution of static friction force from the supporting surface which is calculated and compared with kinetic friction. Thus, it is possible to describe the complete range of tribological phenomena: static friction upon the transition to kinetic friction, pure kinetic friction, and the relaxation of kinetic friction to self‐balanced static friction.
Au/TiO2 nanorod‐based Schottky‐type UV photodetectors
Authors: Karaagac Hakan , Erdal Aygun Levent , Parlak Mehmet , Ghaffari Mohammad , Biyikli Necmi , Kemal Okyay Ali 
Published: October 2012

AbstractTiO2 nanorods (NRs) were synthesized on fluorine‐doped tin oxide (FTO) pre‐coated glass substrates using hydrothermal growth technique. Scanning electron microscopy studies have revealed the formation of vertically‐aligned TiO2 NRs with length of ∼2 µm and diameter of 110–128 nm, homogenously distributed over the substrate surface. 130 nm thick Au contacts using thermal evaporation were deposited on the n‐type TiO2 NRs at room temperature for the fabrication of NR‐based Schottky‐type UV photodetectors. The fabricated Schottky devices functioned as highly sensitive UV photodetectors with a peak responsivity of 134.8 A/W (λ = 350 nm) measured under 3 V reverse bias. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theoretical and experimental studies on solubility and reactivity behavior of lysergol, elymoclavine, and dihydrolysergol
Authors: Rohilla Mehak , Goel Neetu , Singh Tej Vir , Venugopalan P. , Kumar N. V. Suresh , Tewari K. 
Published: October 2012

AbstractLysergol, elymoclavine (Δ9,10 and Δ8,9 regioisomers), and dihydrolysergol are important members of ergolines. The present work reports their comparative study in gas and solvent phase (water) that has been performed both experimentally and theoretically. Theortical calculations have been carried within the density functional theory formalism to analyze the structural and electronic properties of these molecules with B3LYP hybrid exchange–correlational fuctional in conjunction with 6‐311++G (d,p) basis set. Hessian calculations are performed at B3LYP/6‐31G (d,p) level of theory in gas phase as well as other solvent phases. Solvent phase calculations are performed using Onsager reaction field model as implemented in Gaussian 03. A good agreement has been found between experimental and theoretical infrared and nuclear magnetic resonance (NMR) spectra. The calculated NMR data has been analyzed statistically. Stability of these regioisomers has been analyzed in terms of the energy gap between highest occupied molecular orbital and lowest unoccupied molecular orbital (HOMO–LUMO gap). Calculations for lysergol and elymoclavine in water as solvent were carried to examine the effect of solvent on the HOMO–LUMO levels and energy of these molecules. © 2012 Wiley Periodicals, Inc.
Real‐time quantum chemistry
Authors: Haag Moritz P. , Reiher Markus 
Published: October 2012

AbstractSignificant progress in the development of efficient and fast algorithms for quantum chemical calculations has been made in the past two decades. The main focus has always been the desire to be able to treat ever larger molecules or molecular assemblies—especially linear and sublinear scaling techniques are devoted to the accomplishment of this goal. However, as many chemical reactions are rather local, they usually involve only a limited number of atoms so that models of about 200 (or even less) atoms embedded in a suitable environment are sufficient to study their mechanisms. Thus, the system size does not need to be enlarged, but remains constant for reactions of this type that can be described by less than 200 atoms. The question then arises how fast one can obtain the quantum chemical results. This question is not directly answered by linear‐scaling techniques. In fact, ideas such as haptic quantum chemistry (HQC) or interactive quantum chemistry require an immediate provision of quantum chemical information which demands the calculation of data in “real time.” In this perspective, we aim at a definition of real‐time quantum chemistry, explore its realm and eventually discuss applications in the field of HQC. For the latter, we elaborate whether a direct approach is possible by virtue of real‐time quantum chemistry. © 2012 Wiley Periodicals, Inc.
The structure and electronic property of the smallest C20‐glycine and Gd‐encapsulated C20‐glycine derivatives with potentially biological activity
Authors: Cao Yang , Wang Dawei , Liu Bin , Yao Guijun , Fu Yutuo , Li Xiaojun , Bi Zhenggang 
Published: October 2012

AbstractTheoretical calculations on interaction of the C20 fullerene (consists solely by pentagons) with the smallest amino acid (glycine) were carried out using density‐functional theory method. The glycine molecule energetically prefers to interact with the Top‐site on the C20 cage via its amino nitrogen (N) active site. The stable ordering of three active sites on glycine molecule is NH2‐site > O‐site > OH‐site. Moreover, when the Gd atom is encapsulated to the center of C20‐glycine, the cage volume obviously increase ∼24.8%; and the endohedral atom induces the generation of two strong bands in the partial density of states spectra, which could cause the effect on optical properties. Additionally, it is also found that the modified C20‐glycine derivative by Gd atom can reduce the thermodynamic and kinetic stabilities. It could be expected that the study may provide a theoretical reference in exploring their intrinsic feature structurally to antitumor activity. © 2012 Wiley Periodicals, Inc.
Theoretical investigation of ytterbium trichelates compounds
Authors: Lakehal Salima , Ouddai Nadia , Hannachi Douniazed , Bououdina Mohmed 
Published: October 2012

AbstractTheoretical studies on ytterbium trichelates, Yb(L)3(L = trifluoromethanesulfonate (OTF), perchlorate (ClO4), p‐toluenesulfonic (TOS), nitrobenzenesulfonic (NBSA), and dodecylsulfate (DOS), are carried out using density functional theory method at the PW91/TZP level, for the first time. All ligands are bidentate and the compounds exhibit a distorted trigonal prismatic structure, with a maximum twist angle obtained for ytterbium p‐toluenesulfonic compound Yb(TOS)3. The quantum theory of atoms in molecules (AIM) and energy decomposition analysis reveal the dominant ionic character in ytterbium–oxygen bonding with a little covalent character. According to the Pearson terminology, the Yb(NBSA)3complex reveals the higher acidity. © 2012 Wiley Periodicals, Inc.
Carbon isotopic (13C and 14C) composition of synthetic estrogens and progestogens
Authors: Griffith David R. , Wacker Lukas , Gschwend Philip M. , Eglinton Timothy I. 
Published: October 2012

RATIONALESteroids are potent hormones that are found in many environments. Yet, contributions from synthetic and endogenous sources are largely uncharacterized. The goal of this study was to evaluate whether carbon isotopes could be used to distinguish between synthetic and endogenous steroids in wastewater and other environmental matrices.METHODSEstrogens and progestogens were isolated from oral contraceptive pills using semi‐preparative liquid chromatography/diode array detection (LC/DAD). Compound purity was confirmed by gas chromatography/flame ionization detection (GC/FID), gas chromatography/time‐of‐flight mass spectrometry (GC/TOF‐MS) and liquid chromatography/mass spectrometry using negative electrospray ionization (LC/ESI‐MS). The 13C content was determined by gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and 14C was measured by accelerator mass spectrometry (AMS).RESULTSSynthetic estrogens and progestogens are 13C‐depleted (δ13Cestrogen = –30.0 ± 0.9 ‰; δ13Cprogestogen = –30.3 ± 2.6 ‰) compared with endogenous hormones (δ13C ~ –16 to –26 ‰). The 14C content of the majority of synthetic hormones is consistent with synthesis from C3 plant‐based precursors, amended with 'fossil' carbon in the case of EE2 and norethindrone acetate. Exceptions are progestogens that contain an ethyl group at carbon position 13 and have entirely 'fossil' 14C signatures.CONCLUSIONSCarbon isotope measurements have the potential to distinguish between synthetic and endogenous hormones in the environment. Our results suggest that 13C could be used to discriminate endogenous from synthetic estrogens in animal waste, wastewater effluent, and natural waters. In contrast, 13C and 14C together may prove useful for tracking synthetic progestogens. Copyright © 2012 John Wiley & Sons, Ltd.
Cipher feedback mode under go‐back‐N and selective‐reject protocols in error channels
Authors: Liang Xiannuan , Xiao Yang , Ozdemir Suat , Vasilakos Athanasios V. , Deng Hongmei 
Published: October 2012

ABSTRACTTo produce ciphertexts, two modes of encryption are applied—block ciphers, which encrypt a fixed size block of plaintext at a time, and stream ciphers, which encrypt stream data, one or more bits at a time. As one of stream ciphers, the cipher feedback (CFB) mode is implemented by a block cipher via multiple stages, and in each stage, 1 bit or a number of bits of plaintext are encrypted at a time. Throughout this paper, the study will focus upon the error performance of the stream‐based CFB under two sliding‐window protocols, go‐back‐N and selective‐reject, in an error channel in terms of throughput. We model the performance of the CFB in terms of application‐level throughput and derive the number of stages needed to achieve the optimal throughput, under a given error rate in an error channel. Copyright © 2012 John Wiley & Sons, Ltd.
Tor traffic analysis using Hidden Markov Models
Authors: Zhioua Sami 
Published: October 2012

ABSTRACTTor protocol has been designed primarily to defend against traffic analysis, which threatens privacy while using Internet. In this paper, we consider a very common threat model where an attacker can observe only the local traffic between the target Tor client and the first Tor relay. We show that even with this restricted threat model, the attacker can infer relevant information about the client's traffic, in particular when exactly new circuits are constructed. This is achieved by analyzing the Tor traffic using Hidden Markov Models (HMMs). The experimental analysis shows that the proposed HMM‐based approach has a high precision (93 % on average) and F‐measure (75 % on average). The more interesting part of the paper discusses how a local attacker can identify the hops forming circuits initiated by the Tor client victim. The attack is based on sampling the timing patterns of the most “probable” paths and then estimating the likelihood of each one of them given a circuit construction packets sequence. The experimental analysis shows that the proposed approach has an acceptable precision (around 50 %) as long as the time delay between HMM learning and the actual traffic analysis is relatively small. Copyright © 2012 John Wiley & Sons, Ltd.
‘Fairy Chimney’‐Shaped Tandem Metamaterials as Double Resonance SERS Substrates
Authors: Cinel Neval A. , Bütün Serkan , Ertaş Gülay , Özbay Ekmel 
Published: October 2012

AbstractA highly tunable design for obtaining double resonance substrates to be used in surface‐enhanced Raman spectroscopy is proposed. Tandem truncated nanocones composed of Au‐SiO2‐Au layers are designed, simulated and fabricated to obtain resonances at laser excitation and Stokes frequencies. Surface‐enhanced Raman scattering experiments are conducted to compare the enhancements obtained from double resonance substrates to those obtained from single resonance gold truncated nanocones. The best enhancement factor obtained using the new design is 3.86 × 107. The resultant tandem structures are named after “Fairy Chimneys” rock formation in Cappadocia, Turkey.
Layered Hybrid Selenoantimonates with Reduced Thermal Conductivity
Authors: Chen Yu‐Chu , Yao Hongbin , Thiagarajan Suraj , Wu Min , Emge Thomas J. , Yang Ronggui , Yu Shuhong , Li Jing 
Published: October 2012

AbstractFour ternary selenoantimonates, Ag2SbSe3(enH) (I), KCu2SbSe3 (II), Cu2SbSe3(pdaH2)0.5 (III), and Cu2SbSe3(bdaH2)0.5 (IV) (en = ethylenediamine, pda = propanediamine, bda = butanediamine) were synthesized by solvothermal reactions using amines as solvents. The structures consist of M/Sb (M = Cu, Ag) intermetallic layers connected by either protonated amines or potassium ions. The optical bandgaps of these compounds were estimated from their optical absorption spectra (Kubelka‐Munk function) with the values ranging from 0.9 to 1.8 eV. Thermal conductivity measurements were carried out on I, III, and IV, as well as on related compounds Cu2SbSe3(en)0.5 and Cu2SbSe3(en). In comparison with the inorganic counterpart compound CuSbSe2, the hybrid structures clearly show significantly reduced thermal conductivity, as a result of incorporation of inorganic‐organic interface. The study demonstrates an effective approach to enhance the thermoelectric efficiency of such material systems.
Mesopores in USY Zeolites II
Authors: Lutz Wolfgang , Enke Dirk , Einicke Wolf‐Dietrich , Täschner Dirk , Kurzhals Rolf 
Published: October 2012

AbstractMicroporous zeolites Na‐Y and K‐Y were converted into the NaNH4‐Y and KNH4‐Y modifications by ion exchange being active in dealumination. Removal of framework aluminium and silicon is accompanied by formation of secondary mesopores. Internal mesopores are formed in the centre of zeolite crystals and external pores at their surface. Formation of mesopores changes the sorption behaviour.Residual alkali metal cations as Na+ or K+ stabilise, however, the framework ≡Si‐O‐Al≡ bonds. Because of inhomogeneous distribution of sodium ions, in NaNH4‐Y less internal but more external mesopores are formed. Potassium ions of KNH4‐Y are more homogeneous distributed over the framework why a more balanced formation of secondary pores takes place.
Muscle fiber‐type distribution, fiber‐type‐specific damage, and the Pompe disease phenotype
Authors: den van Berg L. E. M. , Drost M. R. , Schaart G. , de Laat J. , van Doorn P. A. , van der Ploeg A. T. , Reuser A. J. J. 
Published: October 2012

AbstractPompe disease is a lysosomal storage disorder caused by acid α‐glucosidase deficiency and characterized by progressive muscle weakness. Enzyme replacement therapy (ERT) has ameliorated patients’ perspectives, but reversal of skeletal muscle pathology remains a challenge. We studied pretreatment biopsies of 22 patients with different phenotypes to investigate to what extent fiber‐type distribution and fiber‐type‐specific damage contribute to clinical diversity. Pompe patients have the same fiber‐type distribution as healthy persons, but among nonclassic patients with the same GAA mutation (c.‐32‐13T>G), those with early onset of symptoms tend to have more type 2 muscle fibers than those with late‐onset disease. Further, it seemed that the older, more severely affected classic infantile patients and the wheelchair‐bound and ventilated nonclassic patients had a greater proportion of type 2x muscle fibers. However, as in other diseases, this may be caused by physical inactivity of those patients.
The Model of Human Occupation-Based Intervention for Patients with Stroke: A Randomised Trial
Authors: Shinohara Kazuya , Yamada Takashi , Kobayashi Norikazu , Forsyth Kirsty 
Published: October 2012

Objective/Background This study examined a group of people with cerebrovascular accidents who were in a chronic phase in a Health Care Facility for the Elderly in Japan. The model of human occupation (MOHO)-driven occupational therapy (OT) intervention was compared with interventions that were based on other theories, for example, biomechanical and neurodevelopmental frames of reference. Methods A total of 36 service users were randomly assigned to either an experimental group (who received MOHO-based OT) or a control group (who received “usual OT”). All the service users were assessed using the Activities of Daily Living (ADL), WHO Quality of Life 26 (QOL-26), MOS-36-Item Short Form Health (SF-36) before and after a 12-week OT intervention. Results Based on the results of our study, we found that the experimental group significantly improved in ADL and QOL scores following the MOHO-based OT intervention; in fact, these scores were higher (p < .05) than before the practice. The control group, however, only improved on ADL scores following OT intervention. In addition, when compared with the control group after the interventions, the experimental group had significantly improved (p < .05) scores in the following: ADL, all five domains of QOL-26, and physical functioning, role physical, bodily pain, general health perception, social functioning of SF-36. Conclusion The MOHO-based intervention was more effective in the improvement of ADL and QOL than non-MOHO-based intervention.
New insights into desmosome regulation and pemphigus blistering as a desmosome‐remodeling disease
Authors: Kitajima Yasuo 
Published: October 2012

AbstractDesmosomes in keratinocytes are the most important intercellular adhering junctions that provide structural strength for the epidermis. These junctions are connected directly with desmosomal cadherin proteins. Desmosomal cadherins are divided into four desmogleins (Dsgs), Dsg1–4, and three desmocollins (Dscs), Dsc1–3, all of which are involved in desmosomal adhesion by homo‐ and/or heterophilic binding between Dsgs and Dscs in a Ca2+‐dependent manner. Cadherins are present on the cell surface and anchor keratin intermediate filaments (KIFs) to their inner cytoplasmic surface to generate an intracellular KIF‐skeletal scaffold through several associate proteins, including plakoglobin, plakophillin, and desmoplakins. As such, the desmosomal contacts between adjacent cells generate an intercellular KIF scaffold throughout the whole epidermal sheet. However, despite these critical roles in maintaining epidermal adhesion and integrity, desmosomes are not static structures. Rather, they are dynamic units that undergo regular remodeling, i.e., assembly and disassembly, to allow for cell migration within the epidermis in response to outside‐in signaling during epidermal differentiation. Recently, two cell–cell adhesion states controlled by desmosomes have been recognized, including “stable hyperadhesion (Ca2+‐independent)” and “dynamic weak‐adhesion (Ca2+‐dependent)” conditions. These conditions are mutually reversible through cell signaling events involving protein kinase C (PKC) and epidermal growth factor receptor. Pemphigus vulgaris (PV) is an autoimmune bullous disease caused by anti‐Dsg3 antibodies. Binding of these antibodies to Dsg3 causes endocytosis of Dsg3 from the cell surface and results in the specific depletion of Dsg3 from desmosomes, an event linked to acantholysis in the epidermis. This binding of anti‐Dsg3 antibody to Dsg3 in epidermal keratinocytes activates PKC, to generate the “weak‐adhesion (Ca2+‐dependent)” state of desmosomes. The weak‐adhesion desmosomes appear to be the susceptible desmosomal state and a prerequisite for Dsg3 depletion from desmosomes, pivotal and specific events leading to PV blistering. These observations allow us to propose a concept for pemphigus blistering disorders as a “desmosome‐remodeling impairment disease” involving a mechanism of Dsg3 nonassembly and depletion from desmosomes through PV immunoglobulin G‐activated intracellular signaling events.
URBAN IDENTITY IN COLONIAL TUNISIA: THEMAQĀMĀTOF SALIH SUWAYSI AL-QAYRAWANI
Authors: Katz Kimberly 
Published: October 2012

AbstractThis article presents a microhistory of an early 20th-century Tunisian intellectual, Salih Suwaysi, within the context of cross-regional (Maghrib–Mashriq) literary and intellectual trends. Analyzing Suwaysi's use of the conventional literary genre ofmaqāmātillustrates his deep understanding of the problems caused by France's occupation of Tunisia and highlights the significance of historical and contemporary urban space for the author. Revitalized during thenahḍaperiod,maqāmātwere employed by writers to address issues and problems facing contemporary society, in contrast to some of the earliermaqāmātthat focused on language and language structure more than on narrative content. Suwaysi followed his eastern Mediterranean, especially Egyptian, contemporaries in turning to this genre to convey his critical commentaries on social, religious, and political life under the French Protectorate in Tunisia.