bluuebunny/crossref_metadata_2025 huggingface dataset:
SUBURBANISATION AND INTERNATIONAL IMMIGRATION: THE CASE OF THE BARCELONA METROPOLITAN REGION (1998–2009)
Authors: BAYONA‐CARRASCO JORDI , GIL‐ALONSO FERNANDO
Published: December 2011

In this last decade, Spanish urban areas have received large amounts of international immigrants, modifying (sub)urban dynamics. The paper specifically explores the metropolitan region of Barcelona (RMB), where, between 1998 and 2009, foreign nationality residents rose from 1.8 to 14.9 per cent of total population. Research focuses on the impact of foreign immigration on three specific dynamics: population growth and distribution/segregation of both Spanish and foreign populations within the metropolitan area; their respective residential mobility patterns; and consequences on their age and sex structure. Results show that there are remarkable differences between the two populations: foreign immigrants have preferably settled in the core city's least affluent neighbourhoods and, in a second phase, in inner ring municipalities, while the Spanish population continues to move to suburban municipalities.
Metabolic abnormalities and viral replication are associated with biomarkers of vascular dysfunction in HIV‐infected children
Authors: Miller TL , Borkowsky W , DiMeglio LA , Dooley L , Geffner ME , Hazra R , McFarland EJ , Mendez AJ , Patel K , Siberry GK , Van Dyke RB , Worrell CJ , Jacobson DL ,   Pediatric HIV/AIDS Cohort Study (PHACS)
Published: December 2011

Objectives

HIV‐infected children may be at risk for premature cardiovascular disease. We compared levels of biomarkers of vascular dysfunction in HIV‐infected children (with and without hyperlipidaemia) with those in HIV‐exposed, uninfected (HEU) children enrolled in the Pediatric HIV/AIDS Cohort Study (PHACS), and determined factors associated with these biomarkers.

Methods

A prospective cohort study was carried out. Biomarkers of inflammation [C‐reactive protein (CRP), interleukin‐6 (IL‐6) and monocyte chemoattractant protein‐1 (MCP1)], coagulant dysfunction (fibrinogen and P‐selectin), endothelial dysfunction [soluble intracellular cell adhesion molecule‐1 (sICAM), soluble vascular cell adhesion molecule‐1 (sVCAM) and E‐selectin], and metabolic dysfunction (adiponectin) were measured in 226 HIV‐infected and 140 HEU children. Anthropometry, body composition, lipids, glucose, insulin, HIV disease severity, and antiretroviral therapy were recorded.

Results

The median ages of the children were 12.3 years in the HIV‐infected group and 10.1 years in the HEU group. Body mass index (BMI) z‐scores, waist and hip circumferences, and percentage body fat were lower in the HIV‐infected children. Total and non‐high‐density lipoprotein (HDL) cholesterol and triglycerides were higher in HIV‐infected children. HIV‐infected children also had higher MCP‐1, fibrinogen, sICAM and sVCAM levels. In multivariable analyses in the HIV‐infected children alone, BMI z‐score was associated with higher CRP and fibrinogen, but lower MCP‐1 and sVCAM. Unfavourable lipid profiles were positively associated with IL‐6, MCP‐1, fibrinogen, and P‐ and E‐selectin, whereas increased HIV viral load was associated with markers of inflammation (MCP‐1 and CRP) and endothelial dysfunction (sICAM and sVCAM).

Conclusions

HIV‐infected children have higher levels of biomarkers of vascular dysfunction than do HEU children. Risk factors associated with higher biomarkers include unfavourable lipid levels and active HIV replication.
Levodopa infusion combined with entacapone or tolcapone in Parkinson disease: a pilot trial
Authors: Nyholm D. , Johansson A. , Lennernäs H. , Askmark H.
Published: December 2011

Background and purpose:  Catechol‐O‐methyltransferase inhibitors may be used to decrease levodopa requirement. The objective was to investigate whether the levodopa/carbidopa intestinal gel infusion dose can be reduced by 20% without worsening of motor fluctuations and levodopa concentration stability when oral catechol‐O‐methyltransferase inhibitors are added.

Methods:  A short‐term, randomized, partly blinded, crossover, investigator‐initiated clinical trial was performed, with levodopa/carbidopa intestinal gel combined with oral entacapone and tolcapone on two different days in 10 patients. The primary outcome measure was difference in coefficient of variation of levodopa in plasma between levodopa/carbidopa, levodopa/carbidopa/entacapone, and levodopa/carbidopa/tolcapone. The secondary outcome measures other pharmacokinetic variables, patient‐reported outcome, and blinded analysis of motor performance.

Results:  Variation of plasma levodopa concentrations did not differ significantly between the treatments. The treatments did not differ regarding motor performance. Levodopa concentrations were significantly higher using tolcapone. Concentrations of the metabolite 3‐O‐methyldopa decreased gradually during catechol‐O‐methyltransferase inhibition.

Conclusions:  According to this small, short‐term pilot study, oral catechol‐O‐methyltransferase inhibitors administered in 5‐h intervals may be useful in cases where levodopa/carbidopa intestinal gel dose reduction is wanted. Stability of plasma levodopa levels is not significantly altered, and off‐time is not increased when decreasing the levodopa/carbidopa intestinal gel dose by 20%. Rather, the dose should probably be decreased more than 20%, especially under tolcapone co‐treatment, to avoid increased dyskinesias with time.
Kanter Revisited: Gender, Power and (In)Visibility
Authors: Lewis Patricia , Simpson Ruth
Published: December 2011

This paper revisits Kanter's (1977) seminal workMen and Women of the Corporation, rereading her account of numerical advantage and disadvantage through a poststructuralist lens which exposes hidden dimensions of gendered power. This lens is captured in the ‘(In)visibility Vortex’ (Lewis and Simpson, 2010) which highlights struggles and tensions around the norm through processes of preservation and concealment within the norm as well as dynamics of revealing, exposure and disappearance as features of the margins. The study draws on developments in feminist theorizing, specially around visibility, invisibility and power, to facilitate this rereading. In so doing, the author demonstrate that while Kanter retreated from explanations based on the gendering of organizations or from recognition of gendered power, these dynamics can be identified in her text. The authors suggest that rereading classic texts can surface dimensions of organizations that have contemporary significance and can inform future research.
A comment on ‘Climate change: Social workers’ roles and contributions to policy debates and interventions'
Authors: Peeters Jef
Published: December 2011

Peeters J. A comment on ‘Climate change: Social workers’ roles and contributions to policy debates and interventions'

In this commenting article, I present several critical remarks about Lena Dominelli's contribution to the issue of climate change and its implications for social work.1 In my view, her article lacks three important considerations. First, I argue that the issue of climate change should be addressed as part of a broader, fundamental challenge: the transition of the growth‐based economic system upon which our society is built. Second, within a context of social and ecological injustice, dealing with climate change inevitably requires a dimension of social struggle. Third and lastly, I emphasise social work's role in challenging the social, political and economic structures and processes that bring about climate change.
Isoprene emission‐free poplars – a chance to reduce the impact from poplar plantations on the atmosphere
Authors: Behnke Katja , Grote Rüdiger , Brüggemann Nicolas , Zimmer Ina , Zhou Guanwu , Elobeid Mudawi , Janz Dennis , Polle Andrea , Schnitzler Jörg‐Peter
Published: December 2011

Featured paper: See also the Commentary by Ellis
Neonatal assessments for the preterm infant up to 4 months corrected age: a systematic review
Authors: NOBLE YOLANDE , BOYD ROSLYN
Published: December 2011

Aim  The aim of this study was to systematically review the clinimetric properties of longitudinal neonatal neurobehavioural and neuromotor assessments for preterm infants.

Method  Twenty‐seven assessment measures were identified. The following eight measures met the study inclusion criteria: Assessment of Preterm Infants’ Behaviour (APIB), Neonatal Intensive Care Unit Network Neurobehavioural Scale (NNNS), Test of Infant Motor Performance (TIMP), Prechtl’s Assessment of General Movements (GMs), Neurobehavioural Assessment of the Preterm Infant (NAPI), Dubowitz Neurological Assessment of the Preterm and Full‐term Infant (Dubowitz), Neuromotor Behavioural Assessment (NMBA), and the Brazelton Neonatal Behavioural Assessment Scale (NBAS). The primary purposes included prediction (TIMP, GMs, Dubowitz), discrimination (all assessments), and evaluation of change (TIMP, NAPI). Measures of assessment were included in the study if they were (1) primarily neurobehavioural or neuromotor assessments that were suitable for use with preterm infants (<37 weeks gestation) up to 4 months corrected age and were discriminative, predictive, or evaluative; (2) standardized procedures designed for serial/longitudinal use; or (3) criterion or norm referenced. However, all assessment tools that were not published in English in a peer‐reviewed journal or were primarily neurological assessments, one‐time evaluations, screening tools, or not commercially available were not used.

Results  All of the measures included in the review demonstrated adequate content and construct validity. Concurrent validity was reported for APIB, NNNS, Dubowitz, and GMs. Predictive validity was high for GMs with studies reporting up to 100% senstivity for predicting cerebral palsy at the age of 12 to 24 months. Interrater reliability was strong for the TIMP (intraclass correlation=0.95), GMs (K=0.8), and moderate for the NAPI (r=0.67–0.97). Clinical utility was variable for ease of scoring, interpretability, cost, and access.

Interpretation  In the absence of a criterion standard for neonatal neuromotor assessments, the NNNS and APIB have strong psychometric qualities with better utility for research. Similarly, the GMs, TIMP, and NAPI have strong psychometric qualities but better utility for clinical settings. The GMs has best prediction of future outcome and the TIMP has best evaluative validity.
Indian herbal medicines in the treatment of liver diseases: problems and promises
Authors: Girish Chandrashekaran , Pradhan Suresh Chandra
Published: December 2011

Plant drugs are known to play a major role in the management of liver diseases. There are many plants and their extracts that have been shown to possess hepatoprotective activities. There are more than 300 preparations in Indian system of medicine for the treatment of jaundice and chronic liver diseases. About 600 commercial herbal formulations with claimed hepatoprotective activity are being sold all over the globe. The active phytochemical fraction that imparts hepatoprotective activity has been identified in many plants. These phytochemicals can be isolated and developed as single‐ingredient drugs, with quality and standards of modern medicine. The major problem faced with herbal products is their standardization and their quality assurance. There can be batch‐to‐batch variations in their efficacies as a result of natural and genetic alterations, seasonal changes, differences in soil and climatic conditions, and nutritional status of the medicinal plant. Pharmacological validation of each hepatoprotective plant should include efficacy evaluation against liver diseases induced by various agents. The most effective drugs for each kind of liver disease have to be selected by separate efficacy evaluations. To treat liver disease of known, unknown, or multiple causes, a combination of different herbs with active fractions (or purified compounds) has to be developed. They may prove to be useful in the treatment of infective, toxic, and degenerative diseases of the liver.
A combinatorial in silico and cellular approach to identify a new class of compounds that target VEGFR2 receptor tyrosine kinase activity and angiogenesis
Authors: Kankanala J , Latham AM , Johnson AP , Homer‐Vanniasinkam S , Fishwick CWG , Ponnambalam S
Published: December 2011

BACKGROUND AND PURPOSE Vascular endothelial growth factor receptor 2 (VEGFR2) is an attractive therapeutic target for the treatment of diseases such as cancer. Small‐molecule VEGFR2 inhibitors of a variety of chemical classes are currently under development or in clinical use. In this study, we describe the de novo design of a new generation pyrazole‐based molecule (JK‐P3) that targets VEGFR2 kinase activity and angiogenesis.

EXPERIMENTAL APPROACH JK‐P compound series were designed using de novo structure‐based identification methods. Compounds were tested in an in vitro VEGFR2 kinase assay. Using primary endothelial cells, JK‐P compounds were assessed for their ability to inhibit VEGF‐A‐stimulated VEGFR2 activation and intracellular signalling. We tested these compounds in cell migration, proliferation and angiogenesis assays.

KEY RESULTS JK‐P3 and JK‐P5 were predicted to bind the VEGFR2 kinase domain with high affinity, and both compounds showed pronounced inhibition of endogenous VEGFR2 kinase activity in primary human endothelial cells. Only JK‐P3 inhibited VEGF‐A‐stimulated VEGFR2 activation and intracellular signalling. Interestingly, JK‐P3 inhibited endothelial monolayer wound closure and angiogenesis but not endothelial cell proliferation. Both compounds inhibited fibroblast growth factor receptor kinase activity in vitro, but not basic fibroblast growth factor‐mediated signalling in endothelial cells.

CONCLUSIONS AND IMPLICATIONS This is the first report that describes an anti‐angiogenic inhibitor based on such a pyrazole core. Using a de novo structure‐based identification approach is an attractive method to aid such drug discovery. These results thus provide an important basis for the development of multi‐tyrosine kinase inhibitors for clinical use in the near future.
Delivering Alcohol Neurotoxicity into Nucleus, When Clusterin Meets BclXL: A Commentary
Authors: Suk Kyoungho
Published: December 2011

The study by Kim and colleagues (in press) demonstrated that the expression of nuclear isoform of clusterin is induced by ethanol (EtOH) to participate in apoptotic cell death of neurons in developing rodent brain. EtOH‐induced nuclear clusterin interacts with BclXL, thereby liberating proapoptotic Bax. This study indicates the proapoptotic role of nuclear clusterin in EtOH‐exposed neurons, linking specific nuclear events to alcohol neurotoxicity. The study provides novel insights into the molecular mechanisms underlying fetal alcohol spectrum disorders.
Complementary Learning Systems
Authors: O’Reilly Randall C. , Bhattacharyya Rajan , Howard Michael D. , Ketz Nicholas
Published: December 2011

This paper reviews the fate of the central ideas behind the complementary learning systems (CLS) framework as originally articulated in McClelland, McNaughton, and O’Reilly (1995). This framework explains why the brain requires two differentially specialized learning and memory systems, and it nicely specifies their central properties (i.e., the hippocampus as a sparse, pattern‐separated system for rapidly learning episodic memories, and the neocortex as a distributed, overlapping system for gradually integrating across episodes to extract latent semantic structure). We review the application of the CLS framework to a range of important topics, including the following: the basic neural processes of hippocampal memory encoding and recall, conjunctive encoding, human recognition memory, consolidation of initial hippocampal learning in cortex, dynamic modulation of encoding versus recall, and the synergistic interactions between hippocampus and neocortex. Overall, the CLS framework remains a vital theoretical force in the field, with the empirical data over the past 15 years generally confirming its key principles.
Self‐Service Technology Users and Their Causal Attributions for Service Outcomes
Authors: Jin Rui , DeVaney Sharon A.
Published: December 2011

The increasing infusion of self‐service technologies (SSTs) in service encounters calls for a better understanding of consumers’ responses to this service option. The objective of this study was to investigate how consumers attribute reasons for their success or failure experiences with SSTs and how such attributions affect their service evaluations. A scenario and questionnaire approach was used. Data were collected through an Internet survey sent to randomly selected students from a large Midwestern university. Quantitative analyses revealed that SST users displayed self‐serving bias by tending to ascribe the reasons to be more internal, stable, and controllable for a positive service outcome than for a negative service outcome. In addition, SST uses and employee‐served consumers showed different satisfaction patterns. Findings of the study provided new insight on attribution research and SST research.
Non‐occupational contact sensitization to epoxy resin of bisphenol A among general dermatology patients
Authors: Majasuo Susanna , Liippo Jussi , Lammintausta Kaija
Published: December 2011

Background. Sensitization to epoxy resins often results from occupational exposure in various fields of construction and industry. Non‐occupational sensitization sources and environments have remained overlooked.

Objectives. To analyse non‐occupational and occupational contact sensitization to epoxy resin of bisphenol A among general dermatology patients. Special attention was paid to patients sensitized from non‐occupational sources.

Patients and methods. During a 10‐year period, 6042 general dermatology patients were patch tested with epoxy resin (bisphenol A) in the Dermatology Clinic of Turku University Hospital. The clinical data and the sources of occupational and non‐occupational exposure to epoxy resin were analysed in sensitized patients.

Results. Epoxy resin sensitization was found in 59 patients. Non‐occupational sensitization was found in 21 (35%) patients, whereas the number of occupational cases was 38 (65%). The most common sources of non‐occupational epoxy resin sensitization were materials used in domestic renovation and construction projects and in boat repair.

Conclusions. Non‐occupational sensitization sources account for approximately one‐third of epoxy resin sensitization cases, and therefore represent an important risk among hobbies and leisure activities.
Inhibitory effects of melatonin on the lipopolysaccharide‐induced CC chemokine expression in BV2 murine microglial cells are mediated by suppression of Akt‐induced NF‐κB and STAT/GAS activity
Authors: Min Kyoung‐Jin , Jang Ji Hoon , Kwon Taeg Kyu
Published: December 2011

Abstract:  Melatonin influences sleep and circadian rhythm, and it has anti‐inflammatory functions. However, the mechanism of its anti‐inflammatory roles is not well understood. In our studies, we show that melatonin blocked lipopolysaccharide (LPS)‐induced CCL2 (monocyte chemotactic protein‐1; MCP‐1), CCL5 (Regulated upon Activation, Normal T‐cell Expressed, and Secreted), and CCL9 (macrophage inflammatory protein‐1γ) chemokine mRNA expression in BV2 murine microglial cells. Melatonin markedly inhibited LPS‐induced Akt phosphorylation and NF‐κB activation. Furthermore, melatonin inhibited LPS‐induced STAT1/3 phosphorylation and interferon‐gamma activated sequence (GAS)‐driven transcriptional activity. Interestingly, these effects were not associated with reactive oxygen species scavenging effects of melatonin or melatonin receptor signal pathways. Taken together, our results suggested that melatonin has anti‐inflammatory functions through down‐regulation of chemokine expression by inhibition of NF‐κB and STAT/GAS activation in LPS‐stimulated BV2 murine microglial cell line.
Applying plant DNA barcodes to identify species of Parnassia (Parnassiaceae)
Authors: YANG JUN‐BO , WANG YI‐PING , MÖLLER MICHAEL , GAO LIAN‐MING , WU DING
Published: December 2011

DNA barcoding is a technique to identify species by using standardized DNA sequences. In this study, a total of 105 samples, representing 30 Parnassia species, were collected to test the effectiveness of four proposed DNA barcodes (rbcL, matK, trnH‐psbA and ITS) for species identification. Our results demonstrated that all four candidate DNA markers have a maximum level of primer universality and sequencing success. As a single DNA marker, the ITS region provided the highest species resolution with 86.7%, followed by trnH‐psbA with 73.3%. The combination of the core barcode regions, matK+rbcL, gave the lowest species identification success (63.3%) among any combination of multiple markers and was found unsuitable as DNA barcode for Parnassia. The combination of ITS+trnH‐psbA achieved the highest species discrimination with 90.0% resolution (27 of 30 sampled species), equal to the four‐marker combination and higher than any two or three marker combination including rbcL or matK. Therefore, matK and rbcL should not be used as DNA barcodes for the species identification of Parnassia. Based on the overall performance, the combination of ITS+trnH‐psbA is proposed as the most suitable DNA barcode for identifying Parnassia species. DNA barcoding is a useful technique and provides a reliable and effective mean for the discrimination of Parnassia species, and in combination with morphology‐based taxonomy, will be a robust approach for tackling taxonomically complex groups. In the light of our findings, we found among the three species not identified a possible cryptic speciation event in Parnassia.
Response Measurement Accuracy for Off-Resonance Excitation in Atomic Force Microscopy
Authors: Parker Eason R. , Dick Andrew J.
Published: December 2011

Displacement measurement in atomic force microscopy (AFM) is most commonly obtained indirectly by measuring the slope of the AFM probe and applying a calibration factor. Static calibration techniques operate on the assumption that the probe response approximates single mode behavior. For off-resonance excitation or different operating conditions the contribution of higher modes may become significant. In this paper, changes to the calibrated slope-displacement relationship and the corresponding implications on measurement accuracy are investigated. A model is developed and numerical simulations are performed to examine the effect of laser spot position, tip mass, quality factor and excitation frequency on measurement accuracy. Free response conditions and operation under nonlinear tip-sample forces are considered. Results are verified experimentally using a representative macroscale system. A laser spot positioned at a nominal position between x = 0.5 and 0.6 is determined to minimize optical lever measurement error under conditions where the response is dominated by contributions from the first two modes, due to excitation as well as other factors.
Employing Adaptive Particle Swarm Optimization Algorithm for Parameter Estimation of an Exciter Machine
Authors: Darabi Ahmad , Alfi Alireza , Kiumarsi Bahare , Modares Hamidreza
Published: December 2011

Winding inductances of an exciter machine of brushless generator normally consist of nonsinusoidal terms versus rotor position angle, so evaluations of the inductances necessitate detailed modeling and complicated parameter identification procedures. In this paper, an adaptive particle swarm optimization (APSO), which is a novel heuristic computation technique, is proposed to identify parameters of an exciter machine. The proposed approach evaluates the model parameters just knowing the main field impedance, measured exciter field voltage and current. APSO is employed to solve the optimization problem of minimizing the difference between output quantities (exciter field current) of the model and real systems. Two modifications are incorporated into the conventional particle swarm optimization (PSO) scheme that prevents local convergence and provides excellent quality of final result. Performance of the proposed APSO is compared with those of the real-coded genetic algorithm (GA) and PSO with linearly decreasing inertia weight (LDW-PSO), in terms of the parameter accuracy and convergence speed. Simulation results illustrated in the paper show that the proposed APSO is more successful in comparison with LDW-PSO and GA.
Measurements of SiO2, Polycrystalline Silicon, and Si3N4 Etching Yields Depending on Ion Incident Angle
Authors: Kurihara Kazuaki
Published: December 2011

The ion incident angle dependences of the etching yields of SiO2, polycrystalline silicon (poly-Si), and Si3N4 were studied using a plasma beam irradiation apparatus. The angle dependences were affected not only by the etchant chemistry produced by Ar and/or fluorocarbon gas plasmas, but also by the incident ion energy. Since the incident etchant characteristics were measured, the results are useful for constructing an etching profile simulator.
Electron Transport Properties in HSi(OC2H5)3Vapor
Authors: Yoshida Kosaku , Sato Ran , Yokota Takuya , Kishimoto Yasutaka , Date Hiroyuki
Published: December 2011

The electron swarm parameters in HSi(OC2H5)3(triethoxysilane, TRIES) vapor have been investigated for relatively wide ranges of reduced electric field (E/N). Based on the arrival-time spectra (ATS) method for electrons using a double-shutter drift tube, the drift velocity and the longitudinal diffusion coefficient were measured for theE/N=20–5000 Td, and the ionization coefficient was obtained forE/N=300–5000 Td. The results were compared with those for SiH4and Si(OC2H5)4(tetraethoxysilane, TEOS), to show characteristics similar to the parameters in TEOS. We also determined the electron collision cross sections for TRIES by means of the Boltzmann equation analysis.
Local Spin-Seebeck Effect Enabling Two-Dimensional Position Sensing
Authors: Uchida Ken-ichi , Kirihara Akihiro , Ishida Masahiko , Takahashi Ryo , Saitoh Eiji
Published: December 2011

The spin-Seebeck effect (SSE) in magnetic insulators is shown to be applicable to two-dimensional (2D) position sensing using an Y3Fe5O12 (YIG) slab covered with a Pt-film mesh. When a part of the YIG-slab/Pt-mesh sample was heated, the position of the heated part of the sample was found to be known from the measured SSE signals in the Pt mesh. Since the SSE-based position-sensing method allows commonly-used insulators to produce 2D position information, it may be useful for constructing versatile thermally-driven user-interface devices and image-information sensors.
Composition Analysis of High-Stable Transparent Conductive Zinc Oxide by X-ray Photoelectron Spectroscopy and Secondary Ion Mass Spectroscopy
Authors: Kuchiyama Takashi , Hasegawa Shigehiko , Yamamoto Kenji , Teraoka Yuden , Asahi Hajime
Published: December 2011

The physical properties of high-stable transparent Si-doped zinc oxide (ZnO) films were determined by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS). From XPS, the peak corresponding to the energy of ionized silicon (Si 2p) was observed for all samples after damp heat exposure, even in the aluminum (Al)-doped Si-undoped zinc oxide (ZnO:Al) thin film. SIMS profiles showed an increase in silicon concentration at the surface of ZnO thin films after damp heat exposure. The Ar concentration determined from SIMS measurement showed a clear relationship between the stability and Ar concentration. This can be explained by the packing density of ZnO and a barrier model. Additionally, comparing ZnO:Si with ZnO:Al prepared under the same deposition conditions, we found that silicon can make ZnO thin films more stable.
Investigation of the Galvanic Effect between RuN Barriers and Cu Seed Layers
Authors: Wu Chia-Yang , Lee Wen-Hsi , Chang Shih-Chieh , Wang Ying-Lang
Published: December 2011

In this study, we investigated the galvanic effect between the Cu metals and ruthenium nitride (RuN
x
) films that were deposited at various nitrogen (N2) gas flow rates in chemical mechanical polishing slurries. It was found that the galvanic corrosion of the RuN
x
films was inhibited with increasing N2 gas flow ratio, whereas the galvanic corrosion of the Cu seed layers was enhanced. Electrochemical impedance spectroscopy showed that the galvanic corrosion resistance of RuN
x
increased and that of the ruthenium oxide layer decreased as N2 flow ratio increased. This was because the increase in the N content in the RuN
x
films inhibited the corrosion and oxidation of the Ru metals.
Polarization Dependences of Two-Photon Absorption in Si and GaAs Photodiodes at a Wavelength of 1.55 µm
Authors: Kagawa Toshiaki
Published: December 2011

Photocurrents induced by two-photon absorption (TPA) at a wavelength of 1.55 µm in GaAs and Si photodiodes (PDs) were measured and compared. The photocurrent generated by a GaAs PD depends strongly on the linear polarization direction, which is consistent with the anisotropic nature of TPA in GaAs. In contrast, the photocurrent of a Si PD has a negligible dependence on the polarization direction, indicating that TPA is isotropic in this PD at a wavelength of 1.55 µm. The photocurrents generated by GaAs and Si PDs by elliptically polarized light are consistent with analysis based on the third-order nonlinear susceptibility tensor.
Radio Frequency Performance of Hetero-Gate-Dielectric Tunneling Field-Effect Transistors
Authors: Kang In Man , Jang Jung-Shik , Choi Woo Young
Published: December 2011

Radio frequency (RF) performances of hetero-gate-dielectric tunneling field-effect transistors (HG TFETs) have been compared with those of SiO2-only and high-k-only TFETs in terms of f
T, f
max, gate capacitance, channel resistance, and transconductance. HG TFETs can have higher f
T/f
max and smaller switching time than SiO2-only TFETs and high-k-only TFETs because they have higher g
m and current drivability than SiO2-only TFET and smaller gate capacitance than high-k-only TFET.
Impact of Random Dopant Fluctuation on Size-Dependence of Contact Resistance
Authors: Matsuzawa Kazuya
Published: December 2011

Reducing the size of semiconductor devices causes contact in deca-nano size. Substantial fluctuation of contact resistance is anticipated owing to the reduction of impurity atoms in the contact holes. In this study, the impact of the random dopant fluctuation on the contact resistance is revealed by three-dimensional device simulation with a Schottky contact model. The standard deviation of the contact resistance could become 50%, dominated by the number of impurity atoms in the depletion layer formed by the Schottky barrier. The average value of the contact resistance could increase as the impurity concentration decreases because of the reduction of the tunneling path.
Fabrication and Characterization of Cu2ZnSnSxSe4-xSolid Solution Nanocrystallines
Authors: Cao Yun , Wang Chunrui , Li Bin , Zhang Kang , Xu Xiaofeng , Hu Junqing , Chen Xiaoshuang
Published: December 2011

Cu2ZnSnSxSe4-xnanocrystallines have been synthesized via solvothermal route in ethylenediamine using CuCl, ZnCl2, SnCl4·5H2O, Se, and S powders as reaction reagents. The as-synthesized products were characterized by X-ray powder diffraction, transmission electron microscopy, and high-resolution transmission electron microscopy. The results confirm that the Cu2ZnSnSxSe4-x(0≤x≤4) is a complete solid solution with single phase and uniform composition. The solid solutions Cu2ZnSnSxSe4-x(0<x<4) are single crystalline nanoplates with the diameter of 20–50 nm. Raman spectra of the Cu2ZnSnSxSe4-xnanocrystallines revealed that vibrating modes were modulated byx-values. Photoluminescence spectra of the as-prepared Cu2ZnSnSxSe4-xnanocrystallines showed that one wide emission band with peak position around 1.40 eV which slightly changed withx-values.
Production of Various Carbon Nanoclusters by Impact Reaction Using Light-Gas Gun as Simulation of Asteroid Collisions in Space
Authors: Mieno Tetsu , Hasegawa Sunao , Mitsuishi Kazutaka
Published: December 2011

An impact production of carbon nanoclusters is carried out in nitrogen gas using a two-stage light-gas gun. A small polycarbonate ball (or a stainless steel ball) is injected at about 6.5 km/s into a pressurized target chamber to collide with an aluminum target (or a hexane + aluminum target) in 1 atm of nitrogen gas. We can confirm the production of many types of carbon nanoclusters such as aluminum-encapsulated carbon nanoparticles, carbon nanotubes, and balloonlike nanocarbons. Therefore, it is expected that many types of carbon nanoclusters are produced by impact reactions of asteroids in space, when such reactions take place in a carbon-rich atmosphere. Particularly on Titan satellite, a large number of carbon clusters produced by impacts of asteroids are expected to be stored.
Theoretical Study of Gallium Nitride Crystal Growth Reaction Mechanism
Authors: Ikeda Yuji , Ohmori Norifumi , Maida Noriaki , Senami Masato , Tachibana Akitomo
Published: December 2011

In this work, we investigate GaN(0001) crystal growth focusing on gas-phase and surface reactions from the viewpoint of metalorganic chemical vapor deposition (MOCVD) by ab initio calculations. We consider the adsorption of compounds of Ga and N atoms on a Ga-covered surface cluster model. For the adsorption of these compounds, it is found that Ga–Ga bonds undesirable for the steady growth appear for alkylgallium with amino group, and the compounds which have coordinate bonds with NH3 can be a solution for this problem, since they do not make Ga–Ga bonds.
Characterization of Shock-Recovered BaSi2 Powder
Authors: Kishimura Hiroaki , Matsumoto Hitoshi
Published: December 2011

Shock recovery experiments at pressures of up to 22 GPa on BaSi2 powder are performed using a propellant gun. The shocked samples are characterized using X-ray diffraction analysis, Raman spectroscopy, and scanning electron microscopy (SEM). Only the orthorhombic BaSi2 phase is detected and no evidence of amorphization or phase transition is obtained. The SEM images reveal that the BaSi2 powder is consolidated at pressures below 10 GPa, whereas many cavities in addition to whiskers with diameters of several hundreds of nanometers are formed on the surface of the sample shocked at 10 GPa. These whiskers are due to the eruption of BaSi2 vapor from the cavities and the subsequent mixing of this vapor with air. The shock-induced heat may be the cause of this vaporization.
Universal Formula for Secondary Electron Yield of Metals at High Electron Energy and Incident Angle θ
Authors: Xie Ai-Gen , Zhang Jian , Wang Tie-Bang
Published: December 2011

On the basis of the main physical processes of secondary electron emission, the relationships among the incident energy (W
p0) of primary electrons, the number of secondary electrons (δPEθ) released per primary electron entering the metal at high electron energy and incident angle θ and incident angle (θ) are deduced. In addition, the relationship between the number of secondary electrons (δPE0) released per primary electron entering the metal at θ= 0° and W
p0 is determined. From the experimental results, the relationships among the ratio βθ (the subscript θ means the primary electron is incident at θ in this paper), the ratio at θ= 0° (β0) and θ are obtained. On the basis of relationships among δPEθ, δPE0, βθ, β0, backscattered coefficient ηθ, backscattered coefficient at θ= 0° (η0), secondary electron yield δθ, and secondary electron yield at θ= 0° (δ0), the universal formula for expressing δθ using δ0, ηθ, η0, and θ is deduced. The secondary electron yield calculated from this universal formula and the yields measured experimentally from aluminum and copper are compared. The results suggest that the proposed formula is universal for the estimation of secondary electron yields in the angle range of 0–80° and the energy range of 10–102 keV.
Evaluation of Electrophoretic Migration by Optical and Current Responses to Cyclic-Polarity-Reversed Triangular Voltage
Authors: Sugita Tatsuya , Ohshima Tetsuya
Published: December 2011

We studied the electrophoretic migration of electrophoretic inks by measuring the total reflection at the interface between the electrode and the ink solvent simultaneous with the current response to a cyclic-polarity-reversed triangular voltage. We demonstrated that the current peaks and optical responses to the cyclic-polarity-reversed triangular voltage are effective for the easy evaluation of mobility, the charge amount of ions and ink particles, and the interactions of particles with the electrode and inter-particles. The mobility of the ink particles was measured from the slopes of these peak voltages as functions of the square root of the time rate of the scanning voltage. The offset of line extrapolation indicated the interaction of the particles with the electrode. The optical response was effective for measuring the mobility even when the conductivity of the cell was too large to detect the drift current peaks.
Water-Repellent Silicon Surface with Nanostructure Formed by Catalysis of Single Nanosized Silver Particle
Authors: Nishioka Kensuke , Sueto Tsuyoshi , Yoshino Kenji , Saito Nobuo
Published: December 2011

A water-repellent silicon (Si) surface with a nanostructure was formed by simple wet chemical etching using catalysis of a silver nanoparticle. Water repellency can be increased by forming micro- or nanostructures on the Si surface. A single nanosized silver particle dispersion solution was coated onto a Si(100) substrate with a polished surface. The samples were soaked in an aqueous etching solution of hydrofluoric acid and hydrogen peroxide. The roughness and depth of the surface structure increased with increasing etching time. The Si surface with the nanostructure had a contact angle of 130°, indicating a water-repellent surface, whereas the surface without the nanostructure had a contact angle of 68°.
Power Linearity Measurement in Terahertz Time-Domain Spectroscopy Using Metalized Film Attenuators
Authors: Iida Hitoshi , Shimada Yozo , Kinoshita Moto , Kuroda Hideki , Kitagishi Keiko , Izutani Yusuke
Published: December 2011

We describe a method for evaluating the power linearity over a wide dynamic range of a terahertz time-domain spectroscopy (THz-TDS) system. The dynamic range is achieved by means of metalized film attenuators (MFAs). The evaluation was based on repeated measurements of transmittance in a particular sample at different incident power levels. We apply the method to both focused- and collimated-beam systems and show that the method can be applied to reflectance measurements as well.
A Rapid Culture Technique Produces Functional Dendritic‐Like Cells from Human Acute Myeloid Leukemia Cell Lines
Authors: Ning Jian , Morgan David , Pamphilon Derwood
Published: December 2011

Most anti‐cancer immunotherapeutic strategies involving dendritic cells (DC) as vaccines rely upon the adoptive transfer of DC loaded with exogenous tumour‐peptides. This study utilized human acute myeloid leukemia (AML) cells as progenitors from which functional dendritic‐like antigen presenting cells (DLC) were generated, that constitutively express tumour antigens for recognition by CD8+ T cells. DLC were generated from AML cell lines KG‐1 and MUTZ‐3 using rapid culture techniques and appropriate cytokines. DLC were evaluated for their cell‐surface phenotype, antigen uptake and ability to stimulate allogeneic responder cell proliferation, and production of IFN‐γ; compared with DC derived from normal human PBMC donors. KG‐1 and MUTZ‐3 DLC increased expression of CD80, CD83, CD86, and HLA‐DR, and MUTZ‐3 DLC downregulated CD14 and expressed CD1a. Importantly, both KG‐1 and MUTZ‐3‐derived DLC promoted proliferation of allogeneic responder cells more efficiently than unmodified cells; neither cells incorporated FITC‐labeled dextran, but both stimulated IFN‐γ production from responding allogeneic CD8+ T cells. Control DC produced from PBMC using the FastDC culture also expressed high levels of critical cell surface ligands and demonstrated good APC function. This paper indicates that functional DLC can be cultured from the AML cell lines KG‐1 and MUTZ‐3, and FastDC culture generates functional KG‐1 DLC.
Some Finite Sums Involving Generalized Fibonacci and Lucas Numbers
Authors: Kılıç E. , Ömür N. , T. Ulutaş Y.
Published: December 2011

By considering Melham′s sums (Melham, 2004), we compute various more general nonalternating sums, alternating sums, and sums that alternate according to involving the generalized Fibonacci and Lucas numbers.
Overview of Cell Death Mechanisms Induced by Rose Bengal Acetate-Photodynamic Therapy
Authors: Panzarini Elisa , Inguscio Valentina , Dini Luciana
Published: December 2011

Photodynamic Therapy (PDT) is a non-invasive treatment for different pathologies, cancer included, using three key components: non-toxic light-activated drug (Photosensitizer, PS), visible light, and oxygen. Their interaction triggers photochemical reactions leading to Reactive Oxygen Species (ROS) generation, that mediate cytotoxicity and cell death. In the present paper, the most important findings about the synthetic dye Rose Bengal Acetate (RBAc), an emerging photosensitizer for its efficient induction of cell death, will be reported with the aim to integrate RBAc phototoxicity to novel therapeutic PDT strategies against tumour cells. After its perinuclear intracellular localization, RBAc causes multiple subcellular organelles damage, that is, mitochondria, Endoplasmic Reticulum (ER), lysosomes, and Golgi complex. Indeed, RBAc exerts long-term phototoxicity through activation of both caspase-independent and- dependent apoptotic pathways and autophagic cell death. In particular, this latter cell death type may promote cell demise when apoptotic machinery is defective. The deep knowledge of RBAc photocytotoxicity will allow to better understand its potential photomedicine application in cancer.
Autologous Mesenchymal Stem Cells in Chronic Stroke
Authors: Bhasin Ashu , Srivastava M.V. Padma , Kumaran S. Senthil , Mohanty Sujata , Bhatia Rohit , Bose Sushmita , Gaikwad Shailesh , Garg Ajay , Airan Balram
Published: December 2011

Background: Cell transplantation is a ‘hype and hope’ in the current scenario. It is in the early stage of development with promises to restore function in chronic diseases. Mesenchymal stem cell (MSC) transplantation in stroke patients has shown significant improvement by reducing clinical and functional deficits. They are feasible and multipotent and have homing characteristics. This study evaluates the safety, feasibility and efficacy of autologous MSC transplantation in patients with chronic stroke using clinical scores and functional imaging (blood oxygen level-dependent and diffusion tensor imaging techniques). Methods: Twelve chronic stroke patients were recruited; inclusion criteria were stroke lasting 3 months to 1 year, motor strength of hand muscles of at least 2, and NIHSS of 4–15, and patients had to be conscious and able to comprehend. Fugl Meyer (FM), modified Barthel index (mBI), MRC, Ashworth tone grade scale scores and functional imaging scans were assessed at baseline, and after 8 and 24 weeks. Bone marrow was aspirated under aseptic conditions and expansion of MSC took 3 weeks with animal serum-free media (Stem Pro SFM). Six patients were administered a mean of 50–60 × 106 cells i.v. followed by 8 weeks of physiotherapy. Six patients served as controls. This was a non-randomized experimental controlled trial. Results: Clinical and radiological scanning was normal for the stem cell group patients. There was no mortality or cell-related adverse reaction. The laboratory tests on days 1, 3, 5 and 7 were also normal in the MSC group till the last follow-up. The FM and mBI showed a modest increase in the stem cell group compared to controls. There was an increased number of cluster activation of Brodmann areas BA 4 and BA 6 after stem cell infusion compared to controls, indicating neural plasticity. Conclusion: MSC therapy aiming to restore function in stroke is safe and feasible. Further randomized controlled trials are needed to evaluate its efficacy.
When What Had to Happen Was Not Bound to Happen: History, Chance, Narrative, Evolution
Authors: Beatty John , Carrera Isabel
Published: December 2011

Abstract

What is it for history to matter? Stephen Gould argued that unpredictability is part of the answer. For example, the “fact” that repeated replays of the history of life would end differently every time is a sign that history matters to the course of evolution. But there is a problem here: if a particular point in the past leaves open alternative possible futures, then in what sense does that point in the past matter with regard to which of the outcomes occurs? We argue that unpredictability is central to the importance of history. However, it is not the unpredictability of the future, but rather the unpredictability of the past itself that is the key. History matters when a particular future depends on a particular past that was not bound to happen, but did.
Aus Nordcarolina: The Jewish American South in German Jewish Periodicals of the Nineteenth Century
Authors: Hieke Anton
Published: December 2011

Abstract

For many German Jewish papers of the nineteenth century, the United States of America was held up as an ideal. This holds true especially for the Allgemeine Zeitung des Judentums, then Germany’s most influential Jewish publication. In America, Jews had already achieved what their co-religionists in Germany strove for until complete legal emancipation with the formation of the German Empire in 1871: the transition from ‘Jews in Germany’ via ‘German Jews’ to ‘Germans of the Jewish faith.’ Thus, the experiences of Jews from Germany in America represented the post-emancipation hopes for those who had remained behind.2 When examined for the representation of Jewry living in the American Southern states,3 it becomes apparent that German Jewish papers in their coverage of America largely refrained from a regionalization. Most articles and accounts concerning Jewish life in the South do not show any significant distinctiveness in the perception of the region and its Jews. The incidents presented or the comments sent to the papers might in fact have occurred in respectively dealt with any region of the United States at the time, barring anything that remotely dealt with slavery or secession prior to 1865. When the Jewish South was explicitly dealt with in the papers, however, it either functioned as an ‘über-America’ of the negative stereotypes in respect to low Jewish piety, or took the place of an alternative America of injustice and slavery—the ‘anti-America.’ Jewish Southerners who actively supported the region during the Civil War, or who had internalized the South’s moral values as supporters of the Confederacy and/or slavery were condemned in the strongest words for endangering the existence of ‘America the Ideal.’ As the concept of the United States and its Jewish life is represented in a largely unrealistic manner that almost exclusively focused on the positive aspects of Jewish life in America, the concept of the Jewish South was equally far from being accurate.
Paving the Way: Ismaʿili Genealogy and Mobility along Tajikistan’s Pamir Highway
Authors: Mostowlansky Till
Published: December 2011

Abstract

This article is an ethnographic study of Ismaʿili communities along the Pamir Highway. “The road,” as it is referred to locally, links Southern Kyrgyzstan with settlements in the eastern part of Tajikistan; its construction traces back to Soviet modernization policy. However, the highway’s construction in the course of the twentieth century led not only to a physical, but also a social transformation of the region. Labor migration of Ismaʿili Tajiks to various settlements along the road resulted in ethnically and confessionally mixed communities. Thus, the Pamir Highway as an ethnographic point of reference provides an entry to discussion of topics such as genealogy, identity, diaspora, and the notion of an Ismaʿili heartland.