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We have investigated the origins of photoluminescence from quantum dot (QD) layers prepared by alternating depositions of sub-monolayers and a few monolayers of size-mismatched species, termed as sub-monolayer (SML) epitaxy, in comparison with their Stranski–Krastanov (SK) QD counterparts. Using measured nanostructure sizes and local In-compositions from local-electrode atom probe tomography as input into self-consistent Schrödinger–Poisson simulations, we compute the 3D confinement energies, probability densities, and photoluminescence (PL) spectra for both InAs/GaAs SML- and SK-QD layers. A comparison of the computed and measured PL spectra suggests one-dimensional electron confinement, with significant 3D hole localization in the SML-QD layers that contribute to their enhanced PL efficiency in comparison to their SK-QD counterparts. [ABSTRACT FROM AUTHOR]

We have examined the origins of polytype selection during metal-mediated molecular-beam epitaxy of GaN nanowires (NWs). High-angle annular dark-field scanning transmission electron microscopy reveals [111]-oriented zinc blende (ZB) NWs and [0001]-oriented wurtzite (WZ) NWs, with SixNy at the interface between individual NWs and the Si (001) substrate. Quantitative energy dispersive x-ray spectroscopy reveals a notably higher Si concentration of 7.0% ± 2.3% in zinc blende (ZB) NWs than 2.3% ± 1.2% in wurtzite (WZ) NWs. Meanwhile, density functional theory calculations show that incorporation of 8 at. % Si on the Ga sublattice inverts the difference in formation energies between WZ and ZB GaN, such that the ZB polytype of GaN is stabilized. This identification of Si and other ZB polytype stabilizers will enable the development of polytype heterostructures in a wide variety of WZ-preferring compounds. [ABSTRACT FROM AUTHOR]

ObjectiveTo describe the frequency of myocardial infarction (MI) prior to the diagnosis of systemic lupus erythematosus (SLE) and within the first 2 years of follow-up.MethodsThe systemic lupus international collaborating clinics (SLICC) atherosclerosis inception cohort enters patients within 15 months of SLE diagnosis. MIs were reported and attributed on a specialised vascular event form. MIs were confirmed by one or more of the following: abnormal ECG, typical or atypical symptoms with ECG abnormalities and elevated enzymes (≥2 times upper limit of normal), or abnormal stress test, echocardiogram, nuclear scan or angiogram. Descriptive statistics were used.Results31 of 1848 patients who entered the cohort had an MI. Of those, 23 patients had an MI prior to SLE diagnosis or within the first 2 years of disease. Of the 23 patients studied, 60.9% were female, 78.3% were Caucasian, 8.7% black, 8.7% Hispanic and 4.3% other. The mean age at SLE diagnosis was 52.5±15.0 years. Of the 23 MIs that occurred, 16 MIs occurred at a mean of 6.1±7.0 years prior to diagnosis and 7 occurred within the first 2 years of follow-up. Risk factors associated with early MI in univariate analysis are male sex, Caucasian, older age at diagnosis, hypertension, hypercholesterolaemia, family history of MI and smoking. In multivariate analysis only age (OR=1.06 95% CI 1.03 to 1.09), hypertension (OR=5.01, 95% CI 1.38 to 18.23), hypercholesterolaemia (OR=4.43, 95% CI 1.51 to 12.99) and smoking (OR=7.50, 95% CI 2.38 to 23.57) remained significant risk factors.ConclusionsIn some patients with lupus, MI may develop even before the diagnosis of SLE or shortly thereafter, suggesting that there may be a link between autoimmune inflammation and atherosclerosis.

A classic T-cell phenotype in systemic lupus erythematosus (SLE) is the downregulation and replacement of the CD3ζ chain that alters T-cell receptor signaling. However, genetic associations with SLE in the human CD247 locus that encodes CD3ζ are not well established and require replication in independent cohorts. Our aim was therefore to examine, localize and validate CD247-SLE association in a large multiethnic population. We typed 44 contiguous CD247 single-nucleotide polymorphisms (SNPs) in 8922 SLE patients and 8077 controls from four ethnically distinct populations. The strongest associations were found in the Asian population (11 SNPs in intron 1, 4.99 × 10(-4) < P < 4.15 × 10(-2)), where we further identified a five-marker haplotype (rs12141731-rs2949655-rs16859085-rs12144621-rs858554; G-G-A-G-A; P(hap) = 2.12 × 10(-5)) that exceeded the most associated single SNP rs858554 (minor allele frequency in controls = 13%; P = 4.99 × 10(-4), odds ratio = 1.32) in significance. Imputation and subsequent association analysis showed evidence of association (P < 0.05) at 27 additional SNPs within intron 1. Cross-ethnic meta-analysis, assuming an additive genetic model adjusted for population proportions, showed five SNPs with significant P-values (1.40 × 10(-3) < P< 3.97 × 10(-2)), with one (rs704848) remaining significant after Bonferroni correction (P(meta) = 2.66 × 10(-2)). Our study independently confirms and extends the association of SLE with CD247, which is shared by various autoimmune disorders and supports a common T-cell-mediated mechanism.

ObjectiveAnti-C1q has been associated with systemic lupus erythematosus (SLE) and lupus nephritis in previous studies. We studied anti-C1q specificity for SLE (vs rheumatic disease controls) and the association with SLE manifestations in an international multicenter study.MethodsInformation and blood samples were obtained in a cross-sectional study from patients with SLE (n = 308) and other rheumatologic diseases (n = 389) from 25 clinical sites (84% female, 68% Caucasian, 17% African descent, 8% Asian, 7% other). IgG anti-C1q against the collagen-like region was measured by ELISA.ResultsPrevalence of anti-C1q was 28% (86/308) in patients with SLE and 13% (49/389) in controls (OR = 2.7, 95% CI: 1.8-4, p

We conducted a study to examine how a writing-to-learn assignment influenced student learning of polymer behavior. In particular, we examined the role of specific content and a rhetorical framework as well as a structured writing process including peer review and revision. The student-generated writing was analyzed via a content-directed rubric. Students' conceptual understanding of stress-strain behavior was gauged via a multitiered assessment. Finally, interviews were conducted to probe students' experiences during the writing process. Results indicate that the writing-to-learn assignment was effective in promoting understanding of stress-strain properties, but that further support is needed to help students connect polymer microscopic properties to macroscopic behavior. Specifically, the content requirements and rhetorical framework guided what students included in their writing. Peer review and revision provided students with further opportunities to engage and learn the material.

This paper investigates the cross-linguistic applicability of the concept of frame as developed in the Berkeley FrameNet project. We examine whether the frames created for the annotation of English texts can also function as a tool for the assessment of the accuracy of English-to-Japanese translations. If the semantic structure of a source text is analyzed in terms of the frames evoked by its constituent words and the ways in which the elements of those frames are realized, then those frames, their constituent elements, and their interconnections must somehow be present in the translation. The paper concentrates on passages involving causation, as causal relationships are considered by many to exhibit the most salient differences in rhetorical preference between the two languages.

Objective Thrombosis is a serious complication of systemic lupus erythematosus (SLE). Studies that have investigated the genetics of thrombosis in SLE are limited. We undertook this study to assess the association of previously implicated candidate genes,

We have investigated the influence of non-stoichiometry and local atomic environments on carrier transport in GaAs(N)Bi alloy films using local-electrode atom probe tomography (LEAP) in conjunction with time-resolved terahertz photoconductivity measurements. The local concentrations of N, Bi, and excess As, as well as Bi pair correlations, are quantified using LEAP. Using time-resolved THz photoconductivity measurements, we show that carrier transport is primarily limited by excess As, with the highest carrier mobilities for layers with yBi > 0.035. [ABSTRACT FROM AUTHOR]

Elon Eisenberg,1,2 Rephael Goldman,3 Dorit Schlag-Eisenberg,4 Anat Grinfeld5 1Pain Research Unit, Institute of Pain Medicine, Rambam Health Care Campus, Haifa, Israel; 2B. Rappaport Faculty of Medicine, Technion – Israel Institute of Technology, Haifa, Israel; 3Amitim Clinic, Haifa, Israel; 4Department of Medical Imaging, Carmel Medical Center, Haifa, Israel; 5Department of Medical Imaging, Rambam Health Care Campus, Haifa, Israel Abstract: Lumbar epidural steroid injections (LESIs) are commonly used for managing lower back pain (LBP) and radicular pain. LESIs are generally considered safe with only rare serious complication. One very rare complication that is frequently cited in the literature is adhesive arachnoiditis. However, a literature search failed to detect even one published manuscript, clearly documenting LESI induced arachnoiditis. This article presents two patients who received a transforaminal L5–S1 and two L3–L4 interlaminar LESIs. Although the presented patients developed clear radiological (MRI) findings of arachnoiditis, they were not accompanied by any improvement or deterioration in their clinical condition. The article also reviews the literature on the prevalence, pathogenesis, diagnosis, and clinical features of adhesive arachnoiditis. Literature suggests that adhesive arachnoiditis following LESIs is a rare entity, which – as seen in our patients – has clear radiological characteristics but uncertain pathogenesis. It has a large spectrum of clinical presentation, ranging from an incidental finding to a serious neurological sequela. In at least some patients with adhesive arachnoiditis following LESI, the radiological and clinical findings may fail to correlate with each other. In light of the fact that LESI is one of the most commonly performed procedures for managing LBP, clinicians should be aware of this rare yet existing entity. Keywords: sciatica, spinal stenosis, magnetic resonance imaging, MRI, radicular pain

ObjectiveEvidence points to a decreased breast cancer risk in systemic lupus erythematosus (SLE). We analyzed data from a large multisite SLE cohort, linked to cancer registries.MethodsInformation on age, SLE duration, cancer date, and histology was available. We analyzed information on histological type and performed multivariate logistic regression analyses of histological types according to age, SLE duration, and calendar year.ResultsWe studied 180 breast cancers in the SLE cohort. Of the 155 cases with histology information, 11 were referred to simply as 'carcinoma not otherwise specified'. In the remaining 144 breast cancers, the most common histological type was ductal carcinoma (n = 95; 66%) followed by lobular adenocarcinoma (n = 11; 8%), 15 cancers were of mixed histology, and the remaining ones were special types. In our regression analyses, the independent risk factors for lobular versus ductal carcinoma was age [odds ratio (OR) 1.07, 95% confidence interval (CI) 1.01-1.14] and for the 'special' subtypes it was age (OR 1.06, 95% CI 1.01-1.10) and SLE duration (OR 1.05, 95% CI 1.00-1.11).ConclusionsGenerally, up to 80% of breast cancers are ductal carcinomas. Though our results are not definitive, in the breast cancers that occur in SLE, there may be a slight decrease in the ductal histological type. In our analyses, age and SLE duration were independent predictors of histological status.

We investigate the influence of strain and dislocations on band alignment in GaSb/GaAs quantum dot systems. Composition profiles from cross-sectional scanning tunneling microscopy images are interpolated onto a finite element mesh in order to calculate the distribution of local elastic strain, which is converted to a spatially varying band alignment using deformation potential theory. Our calculations predict that dislocation-induced strain relaxation and charging lead to significant local variations in band alignment. Furthermore, misfit strain induces a transition from a nested (type I) to a staggered (type II) band alignment. Although dislocation-induced strain relaxation prevents the type I to type II transition, electrostatic charging at dislocations induces the staggered band alignment once again. [ABSTRACT FROM AUTHOR]

The different conclusions reached by studies investigating the utility of DSEPs prevent a confident conclusion regarding utility. Some investigators are strong believers in the diagnostic usefulness of this technique. Others are mere skeptical. One possible cause is variable study design. Most studies provide evidence no higher than level III (case reports, expert opinions). Controlled studies, especially with blinded interpreters of the tests, would provide needed evidence of efficacy in view of the existing confusion in the literature. It is our consensus that the current evidence supporting the diagnostic use of DSEPs is Type D and that DSEPs should be regarded as Investigational, meaning that current evidence is insufficient to determine appropriateness. This group does encourage further study.

Complex oxides such as tin-doped indium oxide (ITO) are widely utilized as transparent conductors in a variety of functional devices. Typically, they are fabricated by sputtering, which often requires additional annealing to achieve high transparency and conductivity. Using pulsed laser deposition (PLD), both high transparency and high conductivity have been achieved without annealing, using instead selected gas species and pressures. However, the relative roles of Stranski-Krastanov-like and vapor-liquid-solid (VLS) growth modes during morphological transitions remain controversial. Here, we report on PLD of ITO in an inert-gas environment, identifying the role of plasma-plume expansion in the selection of VLS vs vapor-solid (VS) growth. For the lowest N2 pressure, indium-tin droplet formation, followed by self-catalyzed VLS growth, is observed. With increasing N2 pressure, a transition from VLS to VS growth is apparent. It is hypothesized that oxygen scattering at the lowest N2 pressure induces a metal-rich plume, which leads to metal droplet formation, followed by VLS growth. As the N2 pressure is increased, the plasma-plume and its metal-rich core are compressed, resulting in a transition to VS growth. This tunable compression of the plasma-plume offers a route to the morphological design of a wide range of functional complex oxide devices with tunable optical and electronic performance. [ABSTRACT FROM AUTHOR]