bluuebunny/crossref_metadata_2025 huggingface dataset:
CHINESE STAR-TOF MRPC PRODUCTION AND QA TESTING
Authors:   for the STAR Collaboration (This work is supported by NSF China, under Grant Nos. 10620120287 & 10610285.), WANG YI , WANG XIAOBIN
Published: November 2007

Multi-gap resistive plate camber (MRPC) has been demonstrated to have good time resolution (less than 100 ps), high detection efficiency (higher than 95%) and will be used to construct a full barrel time-of-flight (TOF) detector for the STAR experiment at RHIC. The cylindrical TOF covers a total area of approximately 64 m 2 and about 4000 MRPC modules will be produced. Tsinghua University and University of Science and Technology of China (USTC) are responsible for the STAR MRPC production. In this paper we will describe the Tsinghua and USTC MRPC production facilities. Our MRPC manufacture procedures, detector assembly and testing results are also presented.
THE MONTE-CARLO SIMULATION OF TRANSPORT IN QUANTUM WELL GaAs/AlGaAs HETEROSTRUCTURE DOPED WITH SHALLOW DONORS UNDER IMPURITY BREAKDOWN
Authors: GAVRILENKO L. V. , YA. ALESHKIN V. , DUBINOV A. A.
Published: November 2007

The impurity breakdown was simulated in numerical calculations. The distribution function for an electron in the electric field was calculated using the Monte-Carlo method. The electron concentration in the impurity ground state and in the first subband was determined by solving the rate equations. It was found out that a population inversion between the 1s-level and the bottom of the first subband is likely to arise. The requirements for the population inversion to occur were determined.
PHOTOINDUCED 2D PLASMON MODES IN Cs NANOCLUSTERS ON THE GaAs(100)Ga-RICH SURFACE
Authors: BENEMANSKAYA G. V. , EVTIKHIEV V. P. , FRANK-KAMENETSKAYA G. E.
Published: November 2007

The method of photoyield spectroscopy with s- and p-polarized light excitation is developed for studies of 2D collective modes. The formation of nanoclusters has been studied for the Cs / GaAs (100) Ga -rich interface in a wide coverage range up to ~ 2 ML. Two adsorption phases with the strong Cs – Ga bonding and weak Cs – Cs bonding are found by using both stepwise and dynamic Cs deposition regimes. In the first adsorption phase, local interaction of Cs adatoms with Ga dimers occurs. The transition from the first to the second phase is found to take place at ~ 0.7 ML that corresponds to the saturation of all the Ga -dangling bonds. In the second phase, collective modes in quasi-2D Cs clusters of several sizes depending on the coverage and surface plasmon are revealed.
SEMICONDUCTOR LASERS FOR EFFICIENT AND RELIABLE CW OPERATION IN THE MID- AND FAR-INFRARED: INTERSUBBAND QUANTUM-BOX LASERS
Authors: BOTEZ DAN
Published: November 2007

Intersubband quantum-box (IQB) lasers, that is, devices consisting of 2D arrays of single-stage intersubband QB emitters, are proposed, as an alternative to 30-stage quantum-cascade (QC) devices, as sources for efficient room-temperature (RT) emission in the mid- and far-IR (3–5 and 8–12 μm) wavelength ranges. Preliminary results include: (1) the realization of the first mid-IR (λ = 4.7 μ m ) single-stage emitters operating at RT; (2) etch-and-regrowth at the nanoscale level by employing in situ gas etching and MOCVD regrowth; (3) the formation of 30 nm-diameter SiO 2 posts on 80 nm centers, thus forming the mask for the fabrication of IQBs via in situ etch and regrowth.
FORMATION OF MAGNETIC GaAs:Mn LAYERS FOR InGaAs/GaAs LIGHT EMITTING QUANTUM-SIZE STRUCTURES
Authors: DOROKHIN M. V. , ZVONKOV B. N. , DANILOV YU. A. , PODOLSKII V. V. , DEMINA P. B. , VIKHROVA O. V. , MALYSHEVA E. I. , SAPOZHNIKOV M. V.
Published: November 2007

A possibility of the formation of light emitting devices, containing GaAs : Mn layers, by the MOCVD epitaxy process was demonstrated. It was shown that produced GaAs : Mn layers exhibit ferromagnetic properties at room temperature. Luminescent and electrical properties of the In(Ga)As / GaAs quantum-size heterostructures with incorporated GaAs : Mn layers were studied.
NEAR-FIELD OPTICAL VORTEXES AT NANOSTRUCTURED METALLIC FILMS
Authors: EZHOV A. A. , MAGNITSKII S. A. , MASLOVA N. S. , MUZYCHENKO D. A. , NIKULIN A. A. , PANOV V. I.
Published: November 2007

The scattering of linearly polarized monochromatic light by a small protrusion on a metal surface is analyzed within the framework of perturbation theory. It is shown that even at normal incidence of light slight deviations of the protrusion shape from a circularly symmetric one can lead to formation of optical vortexes in the near-field region. The effect is due to resonant excitation of cylindrical surface plasmon waves. This agrees with the fact that the in-plane near-field intensity distribution experimentally observed by scanning near-field optical microscopy has distinct spiral patterns near metallized nanostructured polymer substrates.
LIGHT EMISSION, ABSORPTION AND AMPLIFICATION IN InAs/GaAs QUANTUM DOTS AND GaAs/AlGaAs QUANTUM WELLS RESULTING FROM OPTICAL PUMPING
Authors: FIRSOV D. A. , VOROBJEV L. E. , BARZILOVICH M. A. , YU. PANEVIN V. , MIKHAYLOV I. V. , FEDOSOV N. K. , SHALYGIN V. A. , TONKIKH A. A. , POLYAKOV N. K. , SAMSONENKO YU. B. , CIRLIN G. E. , ZHUKOV A. E. , PIKHTIN N. A. , TARASOV I. S. , USTINOV V. M. , JULIEN F. H. , SEKOWSKI M. , HANNA S. , SEILMEIER A.
Published: November 2007

Optical phenomena in quantum dot and quantum well nanostructures aimed at the development of mid-infrared lasers based on intraband electron transitions are investigated in the conditions of interband optical pumping. Evolution of photoluminescence spectra and interband light absorption with intensity of interband optical excitation is investigated in InAs / GaAs quantum dot structures. Optically induced intersubband mid-infrared light absorption is studied in undoped tunnel-coupled GaAs / AlGaAs quantum wells. The stabilization of the electron concentration at the ground level of tunnel-coupled quantum wells under increasing pumping level is established.
INFLUENCE OF HYDROSTATIC PRESSURE ON EXCITON PHOTOLUMINESCENCE SPECTRUM OF EXCITON MOLECULES InAs/GaAs
Authors: GAISIN V. A. , NOVIKOV B. V. , SOKOLOV A. S. , SHTROM I. V. , CHUGUNOV V. A. , TALALAEV V. G. , ZAKHAROV N. D. , CIRLIN G. E. , SAMSONENKO YU. B. , TONKIKH A. A. , USTINOV V. P.
Published: November 2007

The influence of hydrostatic pressure in the range 0–12 kbar on exciton photoluminescence spectrum of InAs quantum dot molecules was studied. The molecular terms related luminescence with the increase of excitation density was obtained. For all components baric coefficients were found. Anomalies in baric dependences for p+- and d+- excited molecule states are discussed.
DEPHASING IN PRESENCE OF A MAGNETIC FIELD
Authors: GERMANENKO A. V. , LARIONOVA V. A. , GORNYI I. V. , MINKOV G. M.
Published: November 2007

Effect of the magnetic field on the rate of phase breaking is studied. It is shown that the magnetic field resulting in the decrease of phase relaxation rate [Formula: see text] makes the negative magnetoresistance due to suppression of the electron interference to be smoother in shape and lower in magnitude than that found with constant [Formula: see text]-value. Nevertheless our analysis shows that experimental magnetoconductance curves can be well fitted by the Hikami–Larkin–Nagaoka expression.1 The fitting procedure gives the value of τ/τϕ, where τ is the quasi-momentum relaxation time, which is close to the value of τ/τϕ(B = 0) with an accuracy of 25% or better when the temperature varies within the range from 0.4 to 10 K. The value of the prefactor α found from this procedure lies within the interval 0.9–1.2.
FINE STRUCTURE OF EXCITED EXCITONIC STATES IN QUANTUM DISKS
Authors: GLAZOV M. M. , IVCHENKO E. L. , BALTZ R. V. , TSITSISHVILI E. G.
Published: November 2007

We report on a theoretical study of the fine structure of excited excitonic levels in semiconductor quantum disks. A particular attention is paid to the effect of electron–hole long-range exchange interaction. We demonstrate that even in the axisymmetric quantum disks, the exciton P-shell is split into three sublevels. The analytical results are obtained in the limiting cases of strong and weak confinement. A possibility of exciton spin relaxation due to the resonant LO-phonon-assisted coupling between the P and S shells is discussed.
HIGH TEMPERATURE STABILITY OF OPTICAL PROPERTIES OF InAs QUANTUM DOTS REALIZED BY CONTROLLING OF QUANTUM DOTS ELECTRONIC SPECTRUM
Authors: KRYZHANOVSKAYA N. V. , GLADYSHEV A. G. , BLOKHIN S. A. , VASIL'EV A. P. , SEMENOVA E. S. , ZHUKOV A. E. , MAXIMOV M. V. , LEDENTSOV N. N. , USTINOV V. M. , WARMING T. , WIECZOREK W. , BIMBERG D.
Published: November 2007

The optical properties of InAs /( Al ) GaAs quantum dots (QDs) overgrowth by thin AlAs / InAlAs layers are studied as a function of temperature from 10 to 500 K. The QDs emit at 1.27 μm at room temperature. It is shown that the QD energetic spectrum can be tuned by overgrowth of AlAs / InAlAs to provide high temperature stability of the QDs optical properties. Transport of carriers between neighboring QDs is absent, and the carrier distribution remains nonthermal up to room temperature. It is shown that suppression of the thermal escaping of the carriers from QDs is conditioned by high energy separation between ground and excited states, absence of wetting layer level, and increase of carrier localization energy in QDs in case of the Al 0.3 Ga 0.7 As matrix.
GROWTH AND CHARACTERIZATION OF MULTI-LAYER 1.3 μm QUANTUM DOT LASERS
Authors: MOWBRAY DAVID , BADCOCK TOM , SELLERS IAN , RAMSAY ANDREW , SKOLNICK MAURICE , LIU HUI-YUN , HOPKINSON MARK , GROOM KRISTIAN , HOGG RICHARD , BEANLAND RICHARD , CHILDS DAVID , ROBBINS DAVID
Published: November 2007

The growth and characterization of multi-layer 1.3 μm InAs - GaAs quantum dot lasers is reported. It is demonstrated that the growth of the GaAs spacer layer, placed between the InAs quantum dot layers, must be carefully optimized to prevent defect formation. With optimized growth very low room temperature threshold current density (J th ) devices are obtained. Typical cw values are 32.5 and 17 A cm-2 for as-grown and HR coated facet devices, respectively. Operation above 100°C is possible. Mechanisms contributing to the temperature sensitivity of J th above room temperature are discussed. By combining the optimized growth with p-type modulation doping of the QDs both low J th and high temperature stability of J th are achieved at room temperature.
VARIATION OF IN-PLANE LATTICE CONSTANT OF Si/Ge/Si HETEROSTRUCTURES WITH Ge QUANTUM DOTS
Authors: NIKIFOROV ALEXANDER , ULYANOV VLADIMIR , SHAIDUK ROMAN , TEYS SERGEY , GUTAKOVSKY ANTON , PCHELYAKOV OLEG
Published: November 2007

Experimental data are presented on variations of the in-plane lattice constant of Ge and Si films in the course of the MBE film growth on the silicon (100) surface. The in-plane lattice constant of the silicon film is shown to alter as the film grows; the changes reflect the process of relaxation of elastic strains that result from the misfit of the germanium and silicon lattice constants. Due to the presence of germanium islands, a considerably thicker silicon film is required to provide the strain relaxation. The dependence of distortion penetration depth to the silicon film on the effective germanium film thickness is obtained. TEM studies indicate the vertical ordering of the germanium island layers when the thickness of the Si layer in between Ge layers is not sufficient to provide the full strain relaxation.
BICHKOV–RASHBA SPIN–ORBIT SPLITTING IN KINETIC BINDING REGIME IN HgCdTe ACCUMULATION LAYERS
Authors: RADANTSEV V. F. , KRUZHAEV V. V.
Published: November 2007

The Rashba effect peculiarities in gated accumulation layers on the zero-gap HgCdTe are studied theoretically and experimentally. It is shown that the kinetic binding is strongly affected by spin–orbit interaction. Although the spin–orbit splitting is smaller in accumulation layers as compared with inversion ones, the "Rashba polarization", Δn/n, can achieve 100% in the kinetic confinement regime.
Outcomes of Stent Thrombosis and Restenosis During Extended Follow-Up of Patients Treated With Bare-Metal Coronary Stents
Authors: Doyle Brendan , Rihal Charanjit S. , O’Sullivan Crochan J. , Lennon Ryan J. , Wiste Heather J. , Bell Malcolm , Bresnahan John , Holmes David R.
Published: November 2007

Background—

Concern regarding risk of late thrombosis after “off-label” treatment with drug-eluting stents has prompted increased use of bare-metal stents (BMS) in current practice. The sequelae of late BMS failures, however, have been poorly characterized.

Methods and Results—

We performed a retrospective study of 4503 consecutive patients treated with at least 1 BMS and dual antiplatelet therapy between 1994 and 2000. The cumulative incidence of stent thrombosis was 0.5% at 30 days (95% CI, 0.3% to 0.7%), 0.8% at 1 year (95% CI, 0.6% to 1.1%), and 2.0% at 10 years (95% CI, 1.5% to 2.5%). Risk of late (30 days to 1 year) and very late (>1 year) BMS thrombosis was increased among patients considered off label for drug-eluting stent use (
P
=0.024). When saphenous vein graft interventions were excluded, however, risk after off-label use was not significantly increased (
P
=0.23). Other correlates included vein graft intervention, prior myocardial infarction (MI), peripheral vascular disease, and ulcerated lesion (
P
<0.001). Mortality was markedly increased after late and very late BMS thrombosis, particularly during the first 30 days (hazard ratios, 22 [95% CI, 3.1 to 159] and 40 [95% CI, 15 to 107], respectively). The 10-year incidence of clinical restenosis was 18.1% (95% CI, 16.5% to 19.7%), presenting with MI in 2.1% (95% CI, 1.6% to 2.6%). Restenosis presenting with MI was associated with increased mortality compared with no restenosis (hazard ratio, 2.37;
P
<0.001) and with restenosis with a non-MI presentation (hazard ratio, 2.42;
P
<0.001).

Conclusions—

The incidence of BMS thrombosis and of MI caused by restenosis during extended follow-up is significant. Both complications are associated with mortality.
Dark Chocolate Improves Coronary Vasomotion and Reduces Platelet Reactivity
Authors: Flammer Andreas J. , Hermann Frank , Sudano Isabella , Spieker Lukas , Hermann Matthias , Cooper Karen A. , Serafini Mauro , Lüscher Thomas F. , Ruschitzka Frank , Noll Georg , Corti Roberto
Published: November 2007

Background—

Dark chocolate has potent antioxidant properties. Coronary atherosclerosis is promoted by impaired endothelial function and increased platelet activation. Traditional risk factors, high oxidative stress, and reduced antioxidant defenses play a crucial role in the pathogenesis of atherosclerosis, particularly in transplanted hearts. Thus, flavonoid-rich dark chocolate holds the potential to have a beneficial impact on graft atherosclerosis.

Methods and Results—

We assessed the effect of flavonoid-rich dark chocolate compared with cocoa-free control chocolate on coronary vascular and platelet function in 22 heart transplant recipients in a double-blind, randomized study. Coronary vasomotion was assessed with quantitative coronary angiography and cold pressor testing before and 2 hours after ingestion of 40 g of dark (70% cocoa) chocolate or control chocolate, respectively. Two hours after ingestion of flavonoid-rich dark chocolate, coronary artery diameter was increased significantly (from 2.36±0.51 to 2.51±0.59 mm,
P
<0.01), whereas it remained unchanged after control chocolate. Endothelium-dependent coronary vasomotion improved significantly after dark chocolate (4.5±11.4% versus −4.3±11.7% in the placebo group,
P
=0.01). Platelet adhesion decreased from 4.9±1.1% to 3.8±0.8% (
P
=0.04) in the dark chocolate group but remained unchanged in the control group.

Conclusions—

Dark chocolate induces coronary vasodilation, improves coronary vascular function, and decreases platelet adhesion 2 hours after consumption. These immediate beneficial effects were paralleled by a significant reduction of serum oxidative stress and were positively correlated with changes in serum epicatechin concentration.
Angiotensin-(1-7) Counterregulates Angiotensin II Signaling in Human Endothelial Cells
Authors: Sampaio Walkyria O. , Henrique de Castro Carlos , Santos Robson A.S. , Schiffrin Ernesto L. , Touyz Rhian M.
Published: November 2007

Angiotensin (Ang)-(1-7), acting through the Mas receptor, opposes the actions of Ang II. Molecular mechanisms for this are unclear. Here we sought to determine whether Ang-(1-7) influences Ang II signaling in human endothelial cells, focusing specifically on Src homology 2-containing inositol phosphatase 2 (SHP-2) and its interaction with c-Src. Ang II–induced phosphorylation of c-Src, extracellular signal regulated kinase (ERK)1/2, and SHP-2 and activation of NAD(P)H oxidase were assessed in the absence and presence of Ang-(1-7) (10−6mol/L, 15 minutes) by immunoblotting and lucigenin-enhanced chemiluminescence, respectively. (D-Ala7)-Ang I/II (1-7) (Ang fragment 1-7 receptor antagonist) was used to block Ang-(1-7) effects. Association between SHP-2 and c-Src was assessed by immunoprecipitation/immunoblotting studies. Ang II significantly increased activation of c-Src, ERK1/2, and NAD(P)H oxidase and reduced phosphorylation of SHP-2 (P<0.05) in human endothelial cells. These effects were abrogated in cells pre-exposed to Ang-(1-7). Ang fragment 1-7 receptor antagonist pretreatment blocked the negative modulatory actions of Ang-(1-7) on Ang II–induced signaling. Ang-(1-7) alone did not significantly alter phosphorylation of c-Src, ERK1/2, and SHP-2 and had no effect on basal activity of NAD(P)H oxidase. SHP-2 and c-Src were physically associated in the basal state. This association was increased by Ang-(1-7) and blocked by Ang fragment 1-7 receptor antagonist. Our findings demonstrate that, in human endothelial cells, Ang-(1-7) negatively modulates Ang II/Ang II type 1 receptor–activated c-Src and its downstream targets ERK1/2 and NAD(P)H oxidase. We also show that SHP-2-c-Src interaction is enhanced by Ang-(1-7). These phenomena may represent a protective mechanism in the endothelium whereby potentially deleterious effects of Ang II are counterregulated by Ang-(1-7).
LA419, a Novel Nitric Oxide Donor, Prevents Pathological Cardiac Remodeling in Pressure-Overloaded Rats Via Endothelial Nitric Oxide Synthase Pathway Regulation
Authors: Ruiz-Hurtado Gema , Fernández-Velasco María , Mourelle Marisabel , Delgado Carmen
Published: November 2007

Reduced endogenous NO production has been described in cardiovascular disorders as cardiac hypertrophy and heart failure. The therapy with conventional nitrates is limited by their adverse hemodynamic effects and drug tolerance. The novel NO donor LA419 has demonstrated important antithrombotic and anti-ischemic properties without those adverse effects. The aim of this study was to evaluate the effect of LA419 chronic treatment on cardiac hypertrophy development in a progressive model of left ventricular hypertrophy. Rats were randomly divided into 6 groups: sham and clip (euthanized 7 weeks after aortic stenosis), sham+vehicle, sham+LA419, clip+vehicle, and clip+LA419 (euthanized 14 weeks after the surgery and treated with vehicle or 30 mg/kg of LA419 once left ventricular hypertrophy was established). LA419 treatment for 7 weeks induced a marked reduction in the heart:body weight ratio (4.10±0.28 and 3.38±0.06 mg/g in clip+vehicle versus clip+LA419;
P
<0.001) and left ventricular diameter (11.96±0.25 and 9.90±0.20 mm in clip+vehicle versus clip+LA419;
P
<0.001) without modifying the high blood pressure observed in stenosed rats. Histological analysis revealed that LA419 attenuated myocardial and perivascular fibrosis observed in rats with pressure overload for 14 weeks. In addition, LA419 treatment restored endothelial NO synthase and caveolin-3 expression levels, enhanced the interaction between endothelial NO synthase and its positive regulator the heat shock protein 90, and re-established the normal cardiac content of cGMP in stenosed rats. Thus, LA419 prevented the progression to maladaptative cardiac hypertrophy in response to prolonged pressure overload through a mechanism that involved the re-establishment of the endothelial NO synthase signaling pathway.
Natriuretic Peptide Precursor A Gene Polymorphisms and Risk of Blood Pressure Progression and Incident Hypertension
Authors: Conen David , Glynn Robert J. , Buring Julie E. , Ridker Paul M , Zee Robert Y.L.
Published: November 2007

We tested the hypothesis that natriuretic peptide precursor A gene polymorphisms are significantly associated with blood pressure progression and incident hypertension among healthy, middle-aged women. We performed a prospective cohort study among 18 437 white women participating in the Women’s Health Study who were free of hypertension at baseline. Two previously characterized single nucleotide polymorphisms within the natriuretic peptide precursor A gene (rs5063 G>A and rs5065 T>C) were genotyped. Blood pressure progression at 48 months and incident hypertension during the entire follow-up according to the different genotypes and inferred haplotypes were assessed by logistic regression and Cox proportional hazards models, respectively. At 48 months, 47.4% of women had blood pressure progression. The odds ratio (95% CIs) for blood pressure progression associated with the rs5063 variant was 0.85 (0.76 to 0.94;
P
=0.002). For the rs5065 variant, the corresponding odds ratio was 0.94 (0.88 to 1.00;
P
=0.050). During 9.8 years of follow-up, 29.6% of women developed incident hypertension. Hazard ratios (95% CIs) for incident hypertension were 0.88 (0.80 to 0.96;
P
=0.005) for the rs5063 variant and 0.95 (0.90 to 1.00;
P
=0.068) for the rs5065 variant. The odds ratios (95% CIs) of blood pressure progression for the G-T, G-C, and A-T haplotypes were 1.0 (referent), 0.91 (0.85 to 0.98;
P
=0.007), and 0.80 (0.71 to 0.89;
P
<0.001), respectively. For incident hypertension, the corresponding hazard ratios were 1.0 (referent), 0.95 (0.90 to 1.01;
P
=0.095), and 0.90 (0.81 to 0.99;
P
=0.031), respectively. If corroborated by other large-scale, prospective studies, our findings indicate that the natriuretic peptide precursor A gene plays a significant role in blood pressure regulation and development of hypertension.
A Wind-Induced Thermohaline Circulation Hysteresis and Millennial Variability Regimes
Authors: Ashkenazy Yosef , Tziperman Eli
Published: November 2007

The multiple equilibria of the thermohaline circulation (THC: used here in the sense of the meridional overturning circulation) as function of the surface freshwater flux has been studied intensively following a Stommel paper from 1961. It is shown here that multistability and hysteresis of the THC also exist when the wind stress amplitude is varied as a control parameter. Both the Massachusetts Institute of Technology ocean general circulation model (MITgcm) and a simple three-box model are used to study and explain different dynamical regimes of the THC and THC variability as a function of the wind stress amplitude. Starting with active winds and a thermally dominant thermohaline circulation state, the wind stress amplitude is slowly reduced to zero over a time period of ∼40 000 yr (40 kyr) and then increased again to its initial value over another ∼40 kyr. It is found that during the decreasing wind stress phase, the THC remains thermally dominant until very low wind stress amplitude at which pronounced Dansgaard–Oeschger-like THC relaxation oscillations are initiated. However, while the wind stress amplitude is increased, these relaxation oscillations are present up to significantly larger wind stress amplitude. The results of this study thus suggest that under the same wind stress amplitude, the THC can be either in a stable thermally dominant state or in a pronounced relaxation oscillations state. The simple box model analysis suggests that the observed hysteresis is due to the combination of the Stommel hysteresis and the Winton and Sarachik “deep decoupling” oscillations.
Global Ocean Meridional Overturning
Authors: Lumpkin Rick , Speer Kevin
Published: November 2007

A decade-mean global ocean circulation is estimated using inverse techniques, incorporating air–sea fluxes of heat and freshwater, recent hydrographic sections, and direct current measurements. This information is used to determine mass, heat, freshwater, and other chemical transports, and to constrain boundary currents and dense overflows. The 18 boxes defined by these sections are divided into 45 isopycnal (neutral density) layers. Diapycnal transfers within the boxes are allowed, representing advective fluxes and mixing processes. Air–sea fluxes at the surface produce transfers between outcropping layers. The model obtains a global overturning circulation consistent with the various observations, revealing two global-scale meridional circulation cells: an upper cell, with sinking in the Arctic and subarctic regions and upwelling in the Southern Ocean, and a lower cell, with sinking around the Antarctic continent and abyssal upwelling mainly below the crests of the major bathymetric ridges.
Localization of Multidecadal Variability. Part II: Spectral Origin of Multidecadal Modes
Authors: Dijkstra Henk A. , von der Heydt Anna
Published: November 2007

In a companion paper, the authors have shown that in an idealized Atlantic–Pacific Ocean configuration with a conveyor-type overturning circulation, localized multidecadal variability occurs in the Atlantic. Results suggest that the multidecadal variability originates from the instability of the three-dimensional thermohaline circulation and that the physics of the spatial patterns of the SST anomalies can be understood from a study of an Atlantic-only configuration. Specific internal (multidecadal) modes, which obtain a positive growth factor depending on the background thermohaline flow, are associated with the instability. In this paper, the spectral origin of these internal modes is studied using eigensolution continuation techniques. As in the single-hemispheric case, multidecadal modes arise through mergers of so-called SST modes. In the double-hemispheric case studied here, there actually are two types of multidecadal modes that lead to oscillatory behavior. Depending on the background conditions, one of these oscillatory flows is preferred.
Mass Transport Velocity in Shallow-Water Waves Reflected in a Rotating Ocean with a Coastal Boundary
Authors: Hoydalsvik Frode
Published: November 2007

The mass transport velocity in shallow-water waves reflected at right angles from an infinite and straight coast is studied theoretically in a Lagrangian reference frame. The waves are weakly nonlinear and monochromatic, and propagate in a homogenous, viscous, and rotating ocean. Unlike the traditional approach where the domain is divided into thin boundary layers and a core region, the uniform solution is obtained here without constraints on the thickness of the bottom wave boundary layer. It is shown that the mass transport velocity is not only sensitive to topography, but depends heavily on the interplay between the vertical length scales. Similarities and differences between the cases of a constant depth, a linearly sloping bottom, and a wavy and linearly sloping bottom are discussed. The mass transport velocity can be divided into two main categories—that induced by waves with a frequency close to the inertial frequency, and that induced by waves with a much larger frequency. For waves significantly affected by rotation to first order, the cross-shore mass transport velocity is very small relative to the alongshore mass transport velocity, and the direction of the mass transport velocity is reversed relative to that in waves of much higher frequencies.
Interoperability among Parallel DEVS Simulators and Models Implemented in Multiple Programming Languages
Authors: Wutzler Thomas , Sarjoughian Hessam S.
Published: November 2007

FleXible yet efficient eXecution of heterogeneous simulations benefits from concepts and methods that can support distributed simulation eXecution and independent model development. To enable formal model specification with submodels implemented in multiple programming languages, we propose a novel approach called the Shared Abstract Model (SAM) approach, which supports simulation interoperability for the class of Parallel Discrete Event System Specification (DEVS) compliant simulation models. Using this approach, models written in multiple programming languages can be eXecuted together using alternative implementations of the Parallel DEVS abstract simulator. In this paper, we describe the SAM concept, detail its specification and eXemplify its implementation with two disparate DEVS-simulation engines. We demonstrate the simplicity of integrating simulation of component models written in the programming languages Java, C++ and Visual Basic. We describe a set of illustrative eXamples that are developed in an integrated DEVSJAVA and Adevs environment. Further, we stage simulation eXperiments to investigate the eXecution performance of the proposed approach and compare it with alternatives. We conclude that application domains, in which independently-developed heterogeneous component models consistent with the Parallel DEVS formalism, benefit from a rigorous foundation and are also interoperable across different simulation engines.
Log-Linear Randomized-Response Models Taking Self-Protective Response Behavior Into Account
Authors: Cruyff Maarten J. L. F. , van den Hout Ardo , van der Heijden Peter G. M. , Böckenholt Ulf
Published: November 2007

Randomized response (RR) is an interview technique designed to eliminate response bias when sensitive questions are asked. In RR the answer depends partly on the true status of the respondent and partly on the outcome of a randomizing device. Although RR elicits more honest answers than direct questions do, it is susceptible to self-protective response behavior; that is, the respondent gives an evasive answer irrespective of the outcome of the randomizing device. The authors present a log-linear RR model that accounts for this kind of self-protection (SP). The main results of this SP model are estimates of (1) the probability of SP, (2) the log-linear parameters describing the associations between the sensitive characteristics, and (3) the prevalence of the sensitive characteristics that are corrected for SP. The model is illustrated with two examples from a Dutch survey measuring noncompliance with social welfare rules.
An Introduction to the Dataverse Network as an Infrastructure for Data Sharing
Authors: King Gary
Published: November 2007

The author introduces a set of integrated developments in Web application software, networking, data citation standards, and statistical methods designed to increase scholarly recognition for data contributions; to put some of the universe of data and data-sharing practices on firmer ground; and to facilitate the public distribution of persistent, authorized, and verifiable data, with powerful and easy-to-use technology, even when the data are confidential or proprietary. The goal is to solve some of the political and sociological problems of data sharing via technological means, with the result intended to benefit both the scientific community and the sometimes apparently contradictory goals of individual researchers.
Notes on Replication
Authors: Abbott Andrew
Published: November 2007

This comment argues that although replication will and should gain ground in sociology, that process will be complicated by issues of ownership, mechanics, and security. Replicationism will also change the economy of peer review. Ironically, it could also reveal that sociologists have less agreement on methodological issues than we think.
Overcoming Objections to Open-Source Social Science
Authors: Freese Jeremy
Published: November 2007

Commentators appreciate the benefits of developing improved standards for replicating quantitative results in sociology. Nonetheless, reservations remain, and the author addresses several of them and explains why improved replication standards do not endanger participant confidentiality, do not undermine incentives for collecting data, do not need to wait for greater standardization of data formats, need not require that editors assign a reviewer to actually replicate results, and do not diminish methodological diversity in any positive sense. The author concludes by encouraging sociologists to find a way of moving beyond intermittent discussions of replication standards to collective action.
John Rawls
Authors: Frazer Michael L.
Published: November 2007

John Rawls shares the Enlightenment's commitment to finding moral and political principles which can be reflectively endorsed by all individuals autonomously. He usually presents reflective autonomy in Kantian, rationalist terms: autonomy is identified with the exercise of reason, and principles of justice must be constructed which are acceptable to all on the basis of reason alone. Yet David Hume, Adam Smith and many other Enlightenment thinkers rejected such rationalism, searching instead for principles which can be endorsed by all on the basis of all the faculties of the human psyche, emotion and imagination included. The influence of these sentimentalists on Rawls is clearest in his descriptive moral psychology, but I argue that it is also present in Rawls's understanding of the sources of normativity. Although this debt is obscured by Rawls's explicit “Kantianism,” his theory would be strengthened by a greater understanding of its debts to the sentimentalist Enlightenment.
The Force of Ideas in Spinoza
Authors: Sharp Hasana
Published: November 2007

This paper offers an interpretation of Spinoza's theory of ideas as a theory of power. The consideration of ideas in terms of force and vitality figures ideology critique as a struggle within the power of thought to give life support to some ideas, while starving others. Because ideas, considered absolutely on Spinoza's terms, are indifferent to human flourishing, they survive, thrive, or atrophy on the basis of their relationship to ambient ideas. Thus, the effort to think and live well requires attention to the collective dimensions of thinking life, where “collective” refers to a transpersonal accumulation of ideal power that includes human as well as nonhuman beings. Because it is a matter of force and power rather than truth and falsity, the project of thinking otherwise entails an effort to displace and to reorganize ideas that is best undertaken by coordinating and galvanizing many thinking powers.
Consent and the Legitimacy of Punishment
Authors: Lovett Frank
Published: November 2007

In his paper, “The Right of the Guilty,” Corey Brettschneider aims to develop and defend a theory of punishment within the framework of a liberal-contractarian conception of political legitimacy. My response argues that this attempt to extend the liberal-contractarian theory reveals, in a particularly clear and striking manner, deep and ultimately insurmountable conceptual difficulties for that theory.
Convergence Between Cluster Analysis and the Angoff Method for Setting Minimum Passing Scores on Credentialing Examinations
Authors: Hess Brian , Subhiyah Raja G. , Giordano Carolyn
Published: November 2007

Cluster analysis can be a useful statistical technique for setting minimum passing scores on high-stakes examinations by grouping examinees into homogenous clusters based on their responses to test items. It has been most useful for supplementing data or validating minimum passing scores determined from expert judgment approaches, such as the Ebel and Nedelsky methods. However, there is no evidence supporting how well cluster analysis converges with the modified Angoff method, which is frequently used in medical credentialing. Therefore, the purpose of this study is to investigate the efficacy of cluster analysis for validating Angoff-derived minimum passing scores. Data are from 652 examinees who took a national credentialing examination based on a content-by-process test blueprint. Results indicate a high degree of consistency in minimum passing score estimates derived from the modified Angoff and cluster analysis methods. However, the stability of the estimates from cluster analysis across different samples was modest.
Assessment of Family Physicians' Performance Using Patient Charts
Authors: Goulet François , Jacques André , Gagnon Robert , Racette Pierre , Sieber William
Published: November 2007

Peer-assessment processes with chart review have been used for many years to assess the clinical performance of physicians. The Quebec medical licensing authority has been required by provincial law to assess the practicing Quebec physicians on a nonvoluntary basis. During the period from January 2001 to November 2004, 25 family physicians in active practice were randomly selected from a pool of about 300. For each physician, 25 to 40 patients' medical charts were randomly selected to evaluate the interrater reliability of peer-review assessment of medical charts and to compare ratings based on chart review with a chart-stimulated recall interview to those based on chart review alone. The concordance between chart review alone and that of chart review with chart-stimulated recall interview was 75% for chart keeping, 69% for clinical investigation, 81% for diagnostic accuracy, and 74% for treatment plan. Ratings based on chart review alone achieve moderate levels of reliability (Kappa = 0.44 to 0.56). It appears that some important information about quality of care is missed when only chart review is used.
An Exploration of the Effect of On-Site 12-Step Meetings on Post-Treatment Outcomes among Polysubstance-Dependent Outpatient Clients
Authors: Laudet Alexandre , Stanick Virginia , Sands Brian
Published: November 2007

Rates of return to active substance use after addiction treatment tend to be high; participation in 12-step fellowships (e.g., Alcoholics Anonymous) reduces relapse rates but many clients do not attend or attend for a short period only. This quasi-experimental study uses repeated measurement to explore the role of presence/absence of on-site 12-step meetings during treatment on post-treatment outcomes. Polysubstance-dependent clients ( N = 219) recruited at a program with and one without 12-step on-site, were followed for one year post-treatment. On-site 12-step enhanced 12-step attendance, especially during treatment, and predicted continuous abstinence for the post-treatment year. Holding 12-step meetings on-site is a low-cost strategy that programs should consider to foster post-treatment remission maintenance.
Treated and Untreated Alcohol-Use Disorders
Authors: Moos Rudolf H. , Moos Bernice S.
Published: November 2007

The research described here focused on personal, life context, and help-related factors to trace the long-term course of treated and untreated alcohol-use disorders. A group of 461 individuals who sought help for alcohol problems was surveyed at baseline and 1, 3, 8, and 16 years later. Compared with individuals who remained untreated, individuals who entered treatment and/or Alcoholics Anonymous (AA), and participated in these modalities for a longer interval, were more likely to attain remission. Personal resources associated with social learning, stress and coping, behavior economic, and social control theories predicted the maintenance of remission.
The Life Course Perspective on Drug Use
Authors: Hser Yih-Ing , Longshore Douglas , Anglin M. Douglas
Published: November 2007

This article discusses the life course perspective on drug use, including conceptual and analytic issues involved in developing the life course framework to explain how drug use trajectories develop during an individual's lifetime and how this knowledge can guide new research and approaches to management of drug dependence. Central concepts include trajectories marked by transitions and social capital and turning points influencing changes. The life course perspective offers an organizing framework for classifying varying drug use trajectories, identifying critical events and factors contributing to the persistence or change in drug use, analytically ordering events that occur during the life span, and determining contributory relationships.
Synthesis of Aliphatic-Aromatic Copolyesters by a Melting Bulk Reaction Between Poly(butylene terephthalate) and DL-Oligo(lactic acid)
Authors: Xiang Jun Zhu  , Yiwang Chen  , Jiying Suxiaohui He  , Licheng Tan  , Yang Wang
Published: November 2007

DL-Oligo(lactic acid) (OLA) readily reacts with poly(1,4-butylene terephthalate) (PBT) in the melt leading to the formation of high molecular mass poly(1,4-butylene terephthalate-co-DL-lactide) (BLA) copolymers. The analysis from 1H NMR reveals that transesterification between butylene terephthalate (BT) and lactide (LA) segments during synthesis has occurred. The BLA copolymers are segmented copolyesters with random arrangement, as shown by the sequence structure of BLA copolyester chains and as confirmed by their thermal behavior. The BLA copolyesters show only one melting temperature ( Tm), crystallization temperature ( Tc), and thermal decomposition temperature ( T d) when the reaction between PBT and OLA takes place at 280°C for more than 0.5 h. With increased OLA composition, the Tm, Tc and Td decrease due to fewer aromatic sequences. The copolyester with a PBT/OLA starting molar ratio of 5.9/94.1 is soluble in chloroform, while pristine PBT is only soluble in mixed chloroform/phenol solvent. Conventional size-exclusion chromatography (SEC) polystyrene calibration determined weight-average molecular weight of the copolyester (5.9/94.1 mol mol-1 PBT/OLA) to be 11200 g mol-1.
Synthesis and Thermal Properties of Polythioetherimides Derived from 4,4'-[p-Thiobis(phenylenesulfanyl)]Diphthalic Anhydride and Various Aromatic Diamines
Authors: Liu Jin-Gang , Shibasaki Yuji , Ando Shinji , Ueda Mitsuru
Published: November 2007

An asymmetrical aromatic diamine, 1-(4'-aminophenoxy)-4-(4'-aminophenylenesulfanyl) benzene (OSDA) was synthesized. A series of polythioetherimides (PTEIs) were prepared from a thioether-bridged aromatic dianhydride 4,4'-[ p-thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA) and various aromatic diamines having ether or thioether linkages between phenylene rings by a two-step polycondensation procedure via their soluble poly(amic acid) (PAA) precursors. Medium to high molecular weight PAAs were obtained with inherent viscosities near or higher than 1.0 dL g-1, which is high enough to afford flexible and tough PTEI films except for PI-2 (3SDEA-134APB) and PI-6 (3SDEA- m2SPDA) derived from meta-ether-substituted diamines. PI-2 and PI-6 showed some extent of crystallinity compared to the amorphous natures of the other polymers. The PTEI films exhibit good resistance to organic solvents except for PI-3 (3SDEA-133APB), which is soluble in N-methyl-2-pyrrolidinone (NMP) and sulfuric acid at room temperature. The PTEI films show good thermal stability with the 5% weight loss temperatures being above 480°C both in nitrogen and in air. The glass transition temperatures of the PTEIs are in the range of 155—191°C, which are lower than those of the commercial polyetherimides due to their plural thioether linkages in the main chains.
Preparation and Properties of Novel Poly(urethane-imide)s via Blending of Reactive Polyimide and Epoxy-Terminated Urethane Prepolymers
Authors: Yeganeh Hamid , Mehdipour-Ataei Shahram , Ghaffari Mehdi
Published: November 2007

Polyurethane networks with enhanced thermal stability and electrical insulation properties were prepared from the reaction of epoxy-terminated urethane prepolymers (EPU) and polyimides containing pendant phenol groups (HPI). EPUs were prepared by the reaction of glycidol with NCO-terminated urethane oligomers. The oligomers were prepared from different molecular weight versions of polycaprolactone polyol (CAPA) and hexamethylene diisocyanate. The progress of the reaction was monitored by differential scanning calorimetric analysis in the presence and absence of suitable catalyst. The onset temperature of exothermic reaction of phenolic groups and epoxy rings was chosen as optimum curing temperature and the reaction duration was optimized by gel content measurement. The starting materials and polymers were characterized by conventional spectroscopic methods, and physical, thermal and electrical properties of the crosslinked networks were determined. The novel poly(urethane-imide)s exhibited considerable improvement in thermal and electrical properties in comparison to common polyurethanes.
Understanding Disadvantage Partly Through an Epistemology of Ignorance
Authors: Feenan Dermot
Published: November 2007

This article is concerned with the way in which ignorance is actively constituted or reproduced as an aspect of power. The significance of ignorance as an important site of study is suggested in this article through an examination of the results of a survey of applications by women for Silk, in recognition of senior status as an advocate, and judicial office in Northern Ireland. The survey found that in the male-dominated profession of law more women than men were unsure of criteria for appointment. The survey revealed also a different perceptual world between male and female lawyers and judges in terms of identifying disadvantage on the basis of gender. Male barristers were twice as likely as female barristers to state that female barristers were not under-represented in applications for Silk. None of the male judges acknowledged that the culture of the bench was male, while most women said it was. This survey is supported by analogous illustrations from other fields. The article concludes that the study of ignorance should be added to the field of vision of those working on the intersection of power/knowledge, and that identification of ignorance may require distinctive responses. The general observations in this article may be of relevance in other areas of anti-discrimination and equality law, policy and praxis.
Security and Migration Law in the Less Brave New World
Authors: Dauvergne Catherine
Published: November 2007

This article examines the shifting relationship between security concerns and migration law, considering in particular the tensions in this relationship since the events of September 11, 2001. It focuses on a series of high profile cases testing provisions allowing for the indefinite detention of non-nationals in the United Kingdom, the United States, New Zealand and Canada. These cases are the basis for the conclusion that the transformed securitization of migration law leads to a new challenge for the rule of law. As security becomes the norm for migration law, its traditional exceptionalism is being called into question.
Contributions to a Post-Sovereigntist Understanding of Law: Foucault, Law as Governance, and Legal Pluralism
Authors: Walby Kevin
Published: November 2007

This article proposes an understanding of law that goes beyond the popular association of law with sovereignty, constitutionalism and representative political institutions. By drawing on insights provided by the law as governance and `non-essentialist version of legal pluralism' approaches, the focus is on retrieving the specificity of plural legal and normative ordering strategies. The law as governance approach proposes a modest role for law where law is conceived as connectively situated among a multiplicity of other constitutive modes of regulation. The `non-essentialist version of legal pluralism' is a conventionalist rearticulation of the hitherto unproblematized tradition of legal pluralism. Comparing the law as governance and `non-essentialist version of legal pluralism' approaches contributes to a post-sovereigntist understanding of law. A post-sovereigntist understanding of law focuses on the state as a site for the unification of regulatory projects, but, inspired by Michel Foucault's later works, finds it important to place analyses of law within the context of a decentered economy of productive power and extensive government. This post-sovereigntist understanding not only provides a clearer depiction of the way legal and normative ordering and their interrelations work in the everyday, but raises questions regarding the future of legal pluralism in socio-legal theory.