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Catheter ablation for atrial fibrillation (AF) in comparison to medical therapy alone is known to improve freedom from arrhythmia and quality of life, but the benefit regarding mortality is unclear. The publication of several recent large randomized controlled trials (RCT) comparing ablation with medical therapy has warranted an updated meta-analysis.We sought to compare the effectiveness of catheter ablation versus medical therapy only in patients with AF. MEDLINE, Cochrane, and ClinicalTrials.gov databases were searched from inception until 04/30/2021. Relevant RCTs comparing catheter ablation versus medical therapy in patients with AF were selected.A total of 24 RCTs involving 5730 adult patients were included (2992 in catheter ablation and 2738 in medical therapy). There was a reduction in all-cause mortality with catheter ablation compared with medical therapy only (risk ratio (RR) 0.70 [95% confidence interval (CI) 0.55-0.89]; p = .003). Catheter ablation also demonstrated a reduction in hospitalizations (RR 0.50 [95% CI 0.36-0.70]; p .001), improvement in left ventricular ejection fraction (LVEF) (mean difference [MD] + 5.94% [95% CI 0.40-11.48] p = .04), greater freedom from atrial arrhythmia (RR 2.23 [95% CI 1.79-2.76]; p .001), and AF (RR 1.95 [95% CI 1.44-2.66]; p .001). In subgroup analysis, catheter ablation demonstrated a significant reduction in mortality and hospitalizations among patients with reduced LVEF, and when ablation was compared with antiarrhythmic drug use.In comparison to medical therapy only, catheter ablation for atrial fibrillation reduces mortality, hospitalizations, and increases freedom from arrhythmia.

Empirical evidence suggests that both leisure time and medical care are important for maintaining health. We develop a general equilibrium macroeconomic model in which taxation is a key determinant of the composition of these two inputs in the endogenous accumulation of health capital. In our model, higher taxes lead to using relatively more leisure time and less medical care in maintaining health. We find that difference in taxation between the US and Europe can account for a large fraction of their difference in health expenditure-GDP ratio and almost all of their difference in time input for health production.

BACKGROUND Radiofrequency (RF) ablation with half-normal saline (HNS) has shown promise as a bail-out strategy following failed ventricular tachycardia ablation using standard approaches. OBJECTIVE To use a novel infrared thermal imaging (ITI) model to evaluate biophysical and lesion characteristics during RF ablation using normal saline (NS) and HNS irrigation. METHODS Left ventricular strips of myocardium were excised from fresh porcine hearts. RF ablation was performed using an open-irrigated ablation catheter (Thermocool ST/SF) with NS (n = 75) and HNS (n = 75) irrigation using different power settings (40/50 W), RF durations (30/60 s), contact force of 10-15 g, and flow rate of 15 ml/min. RF lesions were recorded using an infrared thermal camera and border zone, lethal, 100° isotherms were matched with necrotic borders after 2% triphenyltetrazolium chloride staining. Lesion dimensions and isotherms (mm2 ) were measured. RESULTS In total, 150 lesions were delivered. HNS lesions were deeper (6.4 ± 1.1 vs. 5.7 ±0.8 mm; p = .03), and larger in volume (633 ± 153 vs. 468 ± 107 mm3 ; p = .007) than NS lesions. Steam pops (SPs) occurred during 19/75 lesions (25%) in the NS group and 32/75 lesions (43%) in the HNS group (p = .34). Lethal (57.8 ± 6.5 vs. 36.0 ± 3.9 mm2 ; p = .001) and 100°C isotherm areas (16.9 ± 6.9 vs. 3.8 ± 4.2 mm2 ; p = .003) areas were larger and were reached earlier in the HNS group. CONCLUSIONS RFA using HNS created larger lesions than NS irrigation but led to more frequent SPs. The presence of earlier lethal isotherms and temperature rises above 100°C on ITI suggest a potentially narrower therapeutic-safety window with HNS.

Nitrogen (N) is a major ingredient of the atmosphere, but a trace component in the silicate Earth. Its initial inventory in these reservoirs during Earth's early differentiation requires knowledge of N speciation in magmas, for example, whether it outgasses as N-2 or is sequestered in silicate melts as N3-, which remains largely unconstrained over the entire mantle regime. Here we examine N species in anhydrous and hydrous pyrolitic melts at varying P-T-redox conditions by ab-initio calculations, and find N-N bonding under oxidizing conditions from ambient to lower mantle pressures. Under reducing conditions, N interacts with the silicate network or forms N-H bonds, depending on the availability of hydrogen. Redox control of N speciation is demonstrated valid over a P-T space encompassing probable magma ocean depths. Finally, if the Earth accreted from increasingly oxidized materials toward the end of its accretion, an N-enriched secondary atmosphere might be produced and persist until later impacts., Geophysical Research Letters, 49 (7), ISSN:0094-8276, ISSN:1944-8007

The potential role of cyanide-bridged platinum-iron complexes as an anti-cancer Pt(IV) prodrug is studied. We present design principles of a dual-function prodrug that can upon reduction dissociate and release concurrently six cisplatin units and a ferricyanide anion per prodrug unit. The prodrug molecule is a unique complex of hepta metal centers consisting of a ferricyanide core with six Pt(IV) centers each bonded to the Fe(III) core through a cyano ligand. The functionality of the prodrug is addressed through density functional theory (DFT) calculations.

We present a macroeconomic analysis of loan sales driven by bank competition in lending and entrepreneur directed search for funding opportunities. We show how these two features of our macrofinance model can interact to reduce interest rates on loans financed via on‐balance‐sheet activities, and how this can motivate loan sales as a strategy of financing via off‐balance‐sheet activities. The results shed some light on the shift over the years preceding the global financial crisis in the practice of U.S. and European banks, from the traditional “originate‐to‐hold” model of credit provision, toward the “originate‐to‐distribute” approach for credit extension. (JEL E44, G21, G24).

INTRODUCTION Radiation exposure during catheter ablation procedures is a significant hazard for both patients and operators. Atrial fibrillation (AF) ablation procedures have been historically associated with higher fluoroscopy usage than other electrophysiology procedures. Recent efforts have been made to reduce dependence on fluoroscopy during pulmonary vein isolation (PVI) ablation procedures using alternative techniques. METHODS We performed a meta-analysis of studies comparing zero or low fluoroscopy (LF) vs conventional fluoroscopy (CF) approaches for AF ablation. Outcomes of interest included acute and 12-month procedural efficacy, safety, procedure duration, fluoroscopy time, and dose area product. Aggregated data were analyzed with random-effects models, using a Bayesian hierarchical approach. RESULTS A total of 2228 participants (LF, n = 1190 vs CF, n = 1038) from 15 studies were included in the meta-analysis. Risk of AF recurrence in 12 months (odds ratio [OR], 95% confidence interval [95% CI] = 1.343 [0.771-2.340]; P = .297), redo-ablation procedures (OR [95% CI] = 0.521 [0.198-1.323]; P = .186), and procedural complications (OR [95% CI] = 0.99 [0.485-2.204]; P = .979) were similar between LF- and CF-ablation groups. In comparison to CF ablation, LF ablation led to shorter procedure duration (weighted mean differences [WMDs] [95% CI] = -14.6 minutes [-22.5 to -6.8]; P

Schmitt-Grohe and Uribe (1997) demonstrate that a balanced-budget fiscal policy can induce aggregate instability unrelated to economic fundamentals. The empirical relevance of this result has been challenged by subsequent studies. In this paper we show, both analytically and numerically, that such extrinsic instability is an empirically robust plausibility associated with a balanced-budget rule once endogenous capital utilization is taken into consideration. This suggests that the design or operation of a balanced-budget fiscal policy must recognize that it may constitute a practical source of self-fulfilling prophecies and belief-driven fluctuations.

Objective The purpose of this study was to investigate the clinical and histopathological characteristics of GLUT1 in human tongue squamous cell carcinoma (TSCC) and the role of plumbagin (PLB)-mediating GLUT1 in the growth of TSCC. Subjects and methods Forty-five cases of TSCC samples were collected and the expression and location of GLUT1 was analyzed. The role and mechanism of PLB meditating GLUT1 in the inhibitory growth of human TSCC cell line CAL27 were investigated in vitro and vivo. Results The expression of GLUT1 was observed in all samples of human TSCC by immunohistochemical staining. GLUT1 expression was significantly correlated with lymph node metastasis and clinical stage in TSCC. PLB treatment decreased cell viability and colony formation, and increased cell apoptosis in association with the downregulation of GLUT1 via inhibiting PI3K/Akt pathway in vitro and PLB suppressed tumor growth in correlation with downregulation of GLUT1, compared with control group in vivo. Conclusions The findings demonstrated a novel anti-cancer mechanism of PLB, inhibitory TSCC growth via suppressing PI3K/Akt/GLUT1 pathway, which will supply a theoretical basis for PLB to treat TSCC.

Background The aim of this study was to investigate the prevalence of epidemiologic and physician‐diagnosed pollen‐induced AR (PiAR) in the grasslands of northern China and to study the impact of the intensity and time of pollen exposure on PiAR prevalence. Methods A multistage, clustered and proportionately stratified random sampling with a field interviewer‐administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count. Results A total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P

The lack of acid stability in the stomach and of temporal stability when moving through the gastrointestinal (GI) tract has made the development of oral magnetic resonance imaging (MRI) contrast agents based on the platform of Gd3+ -complexes problematic.On the other hand, the negative contrast enhancement produced by the T2 -weighted magnetic metal oxide nanoparticles (NPs) often renders the image readout difficult. Biocompatible NPs of the manganese Prussian blue analog K2 Mn3 [FeII (CN)6 ]2 exhibit extremely high stability under the acidic conditions of the gastric juice. Additionally, the high r1 relaxivity, low toxicity, and high temporal stability of such NPs offer great potential for the development of a true T1 -weighted oral contrast agent for MRI of the entire GI tract.

Aim To describe the clinical characteristics and radiographic findings of horizontal root fractures (HRF) in posterior teeth without a history of dental trauma. Methodology A total 24 patients and 31 HRF cases in 28 posterior teeth were collected from 2006 to 2015. Clinical examinations and radiographic imaging were evaluated. Value of confidence intervals of the proportions were calculated for data presentation. Results The number of males (54%) was similar to females (46%). The patients were predominantly between 50 to 70 years of age (75%). Most HRF cases were found in non-endodontically-treated teeth (79%,), without crown and bridge restorations (82%), and maxillary molars (54%). Many roots of maxillary molars had developed HRF, and the probability was nearly equal. Fractured teeth usually presented with periodontal and apical bone loss, and most patients (92%) were diagnosed with full mouth chronic periodontitis. Tooth wear was another common clinical feature among these patients. Conclusions HRF in posterior teeth without dental trauma occurred mainly in patients’ age between 50 to 70 years old, in non-endodontically-treated teeth, teeth with attrition but without crown and bridge restorations, maxillary molars, and with periodontal and periapical bony destruction. Periodontal condition, occlusal wear, and patients’ age at diagnosis were the possible related factors. HRF in posterior teeth without dental trauma is a diagnostic challenge and even misdiagnosed. A thorough clinical examination, radiographic analysis, and recognition of the clinical characteristics are helpful in the early diagnosis and treatment of HRF. This article is protected by copyright. All rights reserved.

Background Hydrogen sulfide (H2S) is endogenously generated from L-cysteine (L-Cys) by the enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-Lyase (CSE). Hydrogen sulfide is also produced from D-cysteine (D-Cys) by D-Amino acid oxidase (DAO). Methods The H2S production was measured by the methylene blue assay. The expression of DAO was investigated by Western blotting and immunohistochemistry. The short-circuit current (Isc) was recorded using the Ussing chamber technique. Key Results The epithelium in rat jejunum possesses DAO, and generates H2S. D-cysteine, originally used as a negative control for L-Cys, significantly increases the H2S release, which is inhibited by I2CA, an inhibitor of DAO. In vitro study by Ussing chamber technique reveals that D-Cys decreases the Isc across the epithelium of the rat jejunum and enhances the Na+-coupled L-alanine transport. Conclusions & Inferences A novel pathway for the production of H2S by DAO exists in rat jejunum.

We estimated the temporal course of posttraumatic stress disorder (PTSD) in Vietnam-era veterans using a national sample of male twins with a 20-year follow-up. The complete sample included those twins with a PTSD diagnostic assessment in 1992 and who completed a DSM-IV PTSD diagnostic assessment and a self-report PTSD checklist in 2012 (n = 4,138). Using PTSD diagnostic data, we classified veterans into 5 mutually exclusive groups, including those who never had PTSD, and 4 PTSD trajectory groups: (a) early recovery, (b) late recovery, (c) late onset, and (d) chronic. The majority of veterans remained unaffected by PTSD throughout their lives (79.05% of those with theater service, 90.85% of those with nontheater service); however, an important minority (10.50% of theater veterans, 4.45% of nontheater veterans) in 2012 had current PTSD that was either late onset (6.55% theater, 3.29% nontheater) or chronic (3.95% theater, 1.16% nontheater). The distribution of trajectories was significantly different by theater service (p < .001). PTSD remains a prominent issue for many Vietnam-era veterans, especially for those who served in Vietnam.

The World Health Organization (WHO) Composite International Diagnostic Interview (CIDI) posttraumatic stress disorder (PTSD) module is widely used in epidemiological studies of PTSD, yet relatively few data attest to the instrument's diagnostic utility. The current study evaluated the diagnostic utility of the CIDI 3.0 PTSD module with U. S. women Vietnam-era veterans. The CIDI and the Clinician-Administered PTSD Scale (CAPS) were independently administered to a stratified sample of 160 women, oversampled for current PTSD. Both lifetime PTSD and recent (past year) PTSD were assessed within a 3-week interval. Forty-five percent of the sample met criteria for a CAPS diagnosis of lifetime PTSD, and 21.9% of the sample met criteria for a CAPS diagnosis of past-year PTSD. Using CAPS as the diagnostic criterion, the CIDI correctly classified 78.8% of cases for lifetime PTSD (κ = .56) and 82.0% of past year PTSD cases (κ = .51). Estimates of diagnostic performance for the CIDI were sensitivity of .61 and specificity of .91 for lifetime PTSD and sensitivity of .71 and specificity of .85 for past-year PTSD. Results suggest that the CIDI has good utility for identifying PTSD, though it is a somewhat conservative indicator of lifetime PTSD as compared to the CAPS.

Summary Introduction To determine the polymorphism at position 247 of the β2-glycoprotein I (β2GPI) gene in patients with systemic lupus erythematosus (SLE) and healthy controls in the Chinese Han Population and elucidate the relationship between β2GPI polymorphisms and anti-β2GPI levels, and furthermore investigate the correlation between β2GPI polymorphisms and thrombosis in patients with SLE. Methods The β2GPI polymorphisms of 300 patients with SLE and 300 healthy controls were examined by single-specific–primer polymerase chain reaction (SSP-PCR), the efficacy of which was confirmed by sequencing technology. Anti-β2GPI antibodies were tested by enzyme-linked immunosorbent assay. β2GPI polymorphisms associated with thrombosis and the presence of anti-β2GPI antibodies were also statistically evaluated with SPSS software. Results The genotype expressions and the allele frequencies were obtained in both patients with SLE and healthy controls. The SLE patients with thrombosis had significantly higher frequencies of the VV genotype and V allele than those without thrombosis and the controls, and there were no differences in VV genotype and V allele expression between the SLE patients without thrombosis and the controls. In contrast, the presence of anti-β2GPI antibody was related to the VV genotype of β2GPI, and the anti-β2GPI-positive patients had obviously higher frequencies of the VV genotype than the negative ones and the controls. Conclusion The study results suggested that the V/V genotype and the V-encoding allele at position 247 of the β2GPI gene had strong correlation with the occurrence of thrombosis and the production of the anti-β2GPI antibodies, showing that the Val247 β2GPI allele may be one of the genetic risk factors for the development of thrombosis in patients with SLE.

Increasing returns to scale and firms' market power are two potential sources of sunspot expectations in neoclassical models. We show that in New Keynesian models, returns to scale and market power can have fundamentally different implications for broad macroeconomic issues, including self-fulfilling expectations, depending on the nature of price rigidity. Our findings suggest that the design of stabilization monetary policy can depend on precise knowledge about the economy's real and nominal features. Therefore, a clear understanding of the specific economic environment and its relevance to monetary policymaking for ensuring macroeconomic stability can be an integrated part of monetary policy practice.

Objectives Heritability in the risk for developing posttraumatic stress disorder (PTSD) has been established, but most genome-wide association studies (GWASs) of PTSD involve relatively small sample sizes and limited identification of associated genetic loci. This report describes the methodology of a Veterans Affairs (VA) Cooperative Studies Program GWAS of PTSD among combat-exposed U.S. veterans. Methods Probable cases (with PTSD) and probable controls (without PTSD) were identified from among veterans enrolled in the VA Million Veteran Program (MVP) with an algorithm developed using questionnaire responses and electronic health record information. This algorithm, based on a statistical model, relied on medical chart reviews as a reference standard and was refined using telephone interviews. Subsequently, to evaluate the impact of probabilistic phenotyping on statistical power, the threshold probability for case-control selection was varied in simulations. Results As of September 2018, >695,000 veterans have enrolled in MVP. For current analyses, genotyping data were available for >353,000 participants, including >83,000 combat-exposed veterans. A threshold probability of 0.7 for case and control designation yielded an interim >16,000 cases and >33,000 controls. Conclusions A formal methodological approach was used to identify cases and controls for subsequent GWAS analyses to identify genetic risk loci for PTSD.

The effects of thermal annealing treatment on the spectroscopic properties of Pr3+-doped PbWO4 crystals were discussed in detail. The polarized absorption spectra, polarized fluorescence spectra, and fluorescence decay curves of main emission manifolds of the as-grown and annealed Pr3+-doped PbWO4 crystals were measured at room temperature and analyzed. Thermal annealing treatment can diminish most defect centers related to oxygen vacancies and thermal stress. The results demonstrate that thermal annealing treatment can exert a distinct influence on the spectroscopic properties of Pr3+: PbWO4 crystals as promising phosphors and laser materials.

Guidewire insertion is an imperative task of minimally invasive medical procedures. During the procedure, surgeons need to steer long flexible thin wires through patient's blood vessels to reach a clinical target. In this paper, we present a novel approach to model haptics of guidewire insertion process for training simulation. The algorithm also allows for the analysis of the insertion process through subtle physical behaviours of guidewires via force feedbacks. The method includes a 6-DoF dynamic coupling between a rigid body, i.e. the virtual tool and the deformation of the wire simulated as an elastic rod. Instead of using the frictional contact force or the acceleration of the guidewire tip for haptic feedbacks, we compute constrained forces by directly connecting the virtual tool to the end of the guidewire. Therefore, the coupling scheme transmits haptic interactions through constrained dynamics between the virtual tool and the guidewire. Both positional and rotational control modes are implemented and evaluated with respect to the dynamics of the guidewire, user inputs and feedback forces. Experiments highlight the usability of our algorithm for an insertion procedure simulation with complex blood vessel structures. Copyright © 2011 John Wiley & Sons, Ltd.

Labeling of hepatocytes with micron-sized iron oxide particles (MPIOs) enables cell detection using clinical magnetic resonance equipment. For clinical applications, large numbers of cells must be labeled in a simple and rapid manner and have to be applied in suspension. However, all existing protocols are based on adhesion culture labeling with subsequent resuspension, only suitable for small experimental settings. The aim of this study was to investigate the feasibility of preparing MPIO-labeled primary human hepatocytes in a temporary suspension culture. Human hepatocytes were isolated from 16 donors and labeled with MPIOs in suspension, using the Rotary Cell Culture System. Particle incorporation was investigated by light and electron microscopy. Cells were compared with adhesion culture-labeled and subsequently enzymatically resuspended cells. During a period of 5 days, hepatocyte-specific parameters of cell damage (aspartate aminotransferase and alanine aminotransferase) and metabolic activity (urea and albumin) were analyzed (n = 7). Suspension cultures showed a higher outcome in cell recovery compared with the conventional labeling method. When incubated with 180 particles/viable cell for 4 h, the mean particle uptake was 28.8 particles/cell at a labeling efficiency of 95.1%. Labeling in suspension had no adverse effects on cell integrity or metabolic activity. We conclude that labeling of human hepatocytes in suspension is feasible and simple and may serve future large-scale processing of cells.

Background and purpose: Andrographolide is the active component of Andrographis paniculata, a plant used in both Indian and Chinese traditional medicine, and it has been demonstrated to induce apoptosis in different cancer cell lines. However, not much is known about how it may affect the key receptors implicated in cancer. Knowledge of how andrographolide affects receptor trafficking will allow us to better understand new mechanisms by which andrographolide may cause death in cancer cells. Experimental approach: We utilized the well-characterized epidermal growth factor receptor (EGFR) and transferrin receptor (TfR) expressed in epidermoid carcinoma (A-431) cells as a model to study the effect of andrographolide on receptor trafficking. Receptor distribution, the total number of receptors and surface receptors were analysed by immunofluorescence, Western blot as well as flow-cytometry respectively. Key results: Andrographolide treatment inhibited cell growth, down-regulated EGFRs on the cell surface and affected the degradation of EGFRs and TfRs. The EGFR was internalized into the cell at an increased rate, and accumulated in a compartment that co-localizes with the lysosomal-associated membrane protein in the late endosomes. Conclusion and implications: This study sheds light on how andrographolide may affect receptor trafficking by inhibiting receptor movement from the late endosomes to lysosomes. The down-regulation of EGFR from the cell surface also indicates a new mechanism by which andrographolide may induce cancer cell death.

We examine the local effects of equity ownership by investors who are classified as qualified foreign institutional investors in Taiwan. Our empirical analyses reveal a pronounced foreign ownership effect, whereby stocks with high foreign ownership outperform stocks with low foreign ownership. The valuation effect is present even after controlling for firm export, size, or transparency levels. We pursue a performance-based explanation for this effect and find that foreign ownership is strongly and positively associated with firm R&D expenditures and contemporaneous and subsequent firm performance. Our evidence is consistent with foreign investors who enjoy a long-run information advantage over domestic investors.

A methacryl polyhedral oligomeric silsesquioxane (POSS)-reinforced methylsilicone resin was prepared in this work. The structures of the obtained products were confirmed with Fourier transform infrared and atomic force microscopy. The influence of methacryl-POSS on the thermal behavior of the methylsilicone resin was studied by thermogravimetric analysis and isothermal thermogravimetric analysis. The results showed that the thermal stability of the methylsilicone resin was improved, and the degree of thermooxidative degradation was lowered; this was due to the retardation of polymer chain motion and the formation of a protective layer of SiO2. The interlaminar shear strength and flexural strength of quartz fiber/methylsilicone resin composites were tested to determine the effects of methacryl-POSS on the mechanical properties of methylsilicone resin. The results revealed that the mechanical properties of the methylsilicone composites also increased obviously after the incorporation of methacryl-POSS because of the increase in the cure degree and rigidity of the resin. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Colorless block crystals of MOF (metal-organic framework) 1 and 2 were prepared in respective yields of 65 and 60% by thermal treatment of HQA (HQA=6-methoxyl-(8S,9R)-cinchonan-9-ol-3-carboxylic acid) with ZnBr(2) in either H(2)O or D(2)O and 2-butanol at 70 degrees C for 1-2 days. The MOFs 1 and 2 are isostructural, one-dimensional chains in which the local coordination geometry around the Zn center can be best described as a slightly distorted tetrahedron defined by two bromine atoms, one nitrogen atom of quinoline from HQA, and an oxygen atom of carboxylate from HQA. The nitrogen atom of the quinuclidine of HQA is protonated in a zwitterionic form. The MOFs 1 and 2 crystallize in a polar point group (C(2), space group P2(1)) which belongs to ferroelectric active compounds. MOFs 1 and 2 display both ferroelectric behavior and large dielectric constants. Interestingly, at low frequency range the dielectric response to water can achieve an approximate increase of more than 600%. Crystal parameters: 1: C(20)H(28)Br(2)NO(7)Zn, M=619.62, monoclinic, P2(1), a=9.5711(8), b=12.0486(10), c=11.1972(9) A, alpha=gamma=90, beta=98.4(2) degrees , V=1277.39(18) A(3), Z=2, rho(cald)=1.611 mg m(-3), R(1)=0.0499, wR(2)=0.0982, mu=4.126 mm(-1), S=1.015, Flack value=0.032(13); 2: C(20)H(22)D(6)Br(2)NO(7)Zn, M=625.66, monoclinic, P2(1), a=9.5650(9), b=12.0392(11), c=11.1973(10) A, alpha=gamma=90, beta=98.44(2) degrees, V=1275.5(2) A(3), Z=2, rho(cald)=1.629 mg m(-3), R(1)=0.0543, wR(2)=0.1072, mu=4.133 mm(-1), S=1.056, Flack value=0.025(17).

Liquid diffusion experiments conducted on the MIR space station using the Canadian Space Agency QUELD II processing facility and the microgravity isolation mount (MIM) showed that g-jitter significantly increased the measured solute diffusion coefficients. In some experiments, milli-g forced vibration was superimposed on the sample when isolated from the ambient g-jitter; this resulted in markedly increased solute transport. To further explore the effects arising in these long capillary diffusion couples from the absence of unit-gravity and the presence of the forced g-jitter, the effects of a 1 milli-g forcing vibration on the mass transport in a 1.5 mm diameter long capillary diffusion couple have been simulated. In addition, to increase understanding of the role of unit gravity in determining the extent to which gravity can influence measured diffusion coefficient values, comparative experiments involving gold, silver, and antimony diffusing in liquid lead have been carried out using a similar QUELD II facility to that employed in the QUELD II/MIM/MIR campaign but under terrestrial conditions. It was found that buoyancy-driven convection may still persist in the liquid even when conditions are arranged for a continuously decreasing density gradient up the axis of a vertical long capillary diffusion couple due to the presence of small radial temperature gradients.

Background Investigations of work-related low back (LB) and upper extremity (UE) disorders have increasingly utilized multivariable models that include biomechanical/physical and work organization factors. However, the nature of any interactive effects is not well understood. Methods Using questionnaires, high and low exposure groups for biomechanical/physical factors, cognitive demands, cognitive processing, interpersonal demands, participatory management, skill discretion, and time pressure for 289 individuals (U.S. Marines) were identified. Musculoskeletal symptom status was also determined by questionnaire. Individual and biomechanical–psychosocial combinations were examined in adjusted multivariable logistic regression analyses. Results Time pressure was associated with both LB and UE symptoms (odds ratio(s) (OR) range = 2.13–3.09), while higher biomechanical exposures were risk factors for LB symptoms (OR = 2.07; 95% confidence intervals (CI): 1.00–4.35) and concurrent LB and UE symptoms (OR = 2.80; CI: 1.35–5.83). Greater risks for concurrent LB and UE symptoms were indicated for combinations involving higher biomechanical exposure and: time pressure (OR = 2.21; CI: 1.19–4.10); cognitive demands (OR = 2.25; CI: 1.23–4.09); cognitive processing (OR = 2.08; CI: 1.16–3.75); interpersonal demands (OR = 2.44; CI: 1.35–4.41); participatory management (OR = 2.50; CI: 1.30–4.81). Results did not suggest any interaction between biomechanical and work organization factors. Conclusions While no synergism was indicated, the present findings emphasize the need to consider both biomechanical factors and specific work organization factors, particularly time pressure, in reducing musculoskeletal-related morbidity. Am. J. Ind. Med. 43:495–506, 2003. Published 2003 Wiley-Liss, Inc.

This paper compares the quality of quotes submitted by electronic communication networks (ECNs) and by traditional market makers to the Nasdaq quote montage. An analysis of the most active Nasdaq stocks shows that ECNs not only post informative quotes, but also, compared to market makers, ECNs post quotes rapidly and are more often at the inside. Additionally, ECN quoted spreads are smaller than dealer quoted spreads. The evidence suggests that the proliferation of alternative trading venues, such as ECNs, may promote quote quality rather than fragmenting markets. Moreover, the results suggest that a more open book contributes to quote quality.

Background While research has suggested that interventions targeted at occupational stress (job stress) factors may improve clinical and work outcomes related to work-related musculoskeletal disorders, the emerging hypotheses relating occupational stress to work-related upper extremity disorders (WRUEDs) are not particularly well known among occupational health providers and researchers. Methods Generic job stress and health models and multivariable models of WRUEDs were described and evaluated. Results Models on occupational stress and health/WRUEDs offer unique perspectives on the role of occupational stressors on WRUEDs. However, the limited support for the structure and proposed mechanisms of these models suggest that investigations examining and validating proposed biobehavioral pathways are still needed. Discussion Difficulties in conceptualizing occupational stress have, in the past, hindered its systematic incorporation into occupational health research and prevention/intervention strategies. The present paper provides a common basis for researchers and practitioners with diverse backgrounds to understand job stress and its relation to WRUEDs in order to enhance future efforts. Given the present limitations in the field and the need for comprehensive approaches to WRUEDs, there is great potential for occupational health researchers and clinicians to advance knowledge in this area. Am. J. Ind. Med. 41:298–314, 2002. © 2002 Wiley-Liss, Inc.