Strain and localization effects in InGaAs(N) quantum wells: Tuning the magnetic response

We investigated effects of localization and strain on the optical and magneto-optical properties of diluted nitrogen III-V quantum wells theoretically and experimentally. High-resolution x-ray diffraction, photoluminescence (PL), and magneto-PL measurements under high magnetic fields up to 15 T were performed at low temperatures. Bir-Pikus Hamiltonian formalism was used to study the influence of strain, confinement, and localization effects. The circularly polarized magneto-PL was interpreted considering localization aspects in the valence band ground state. An anomalous behavior of the electron-hole pair magnetic shift was observed at low magnetic fields, ascribed to the increase in the exciton reduced mass due to the negative effective mass of the valence band ground state

Chlamydia trachomatis genotypes in a cross-sectional study of urogenital samples from remote Northern and Central Australia

his is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/Abstract OBJECTIVES: The objective was to determine the frequency of trachoma genotypes of Chlamydia trachomatis-positive urogenital tract (UGT) specimens from remote areas of the Australian Northern Territory (NT). SETTING: The setting was analysis of remnants of C. trachomatis positive primarily UGT specimens obtained in the course of clinical practice. The specimens were obtained from two pathology service providers. PARTICIPANTS: From 3356 C. trachomatis specimens collected during May 2012-April 2013, 439 were selected for genotyping, with a focus on specimens from postpubescent patients, in remote Aboriginal communities where ocular trachoma is potentially present. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was the proportion of successfully genotyped UGT specimens that were trachoma genotypes. The secondary outcome measures were the distribution of genotypes, and the frequencies of different classes of specimens able to be genotyped. RESULTS: Zero of 217 successfully genotyped UGT specimens yielded trachoma genotypes (95% CI for frequency=0-0.017). For UGT specimens, the genotypes were E (41%), F (22%), D (21%) and K (7%), with J, H and G and mixed genotypes each at 1-4%. Four of the five genotyped eye swabs yielded trachoma genotype Ba, and the other genotype J. Two hundred twenty-two specimens (50.6%) were successfully genotyped. Urine specimens were less likely to be typable than vaginal swabs (p<0.0001). CONCLUSIONS: Unlike in some other studies, in the remote NT, trachoma genotypes of C. trachomatis were not found circulating in UGT specimens from 2012 to 2013. Therefore, C. trachomatis genotypes in UGT specimens from young children can be informative as to whether the organism has been acquired through sexual contact. We suggest inclusion of C. trachomatis genotyping in guidelines examining the source of sexually transmitted infections in young children in areas where trachoma genotypes may continue to circulate, and continued surveillance of UGT C. trachomatis genotypes

Caractérisation thermophysique et suivi thermique de deux bâtisses réalisées en blocs de terre comprimée

La relance de la construction en terre peut constituer une réponse efficiente pour la réduction des impacts environnementaux liés au secteur du bâtiment. Si, les performances mécaniques du bloc de terre comprimée (BTC) sont avérées, néanmoins leur qualité thermique reste à évaluer. L’objectif de ce travail est justement de quantifier ces performances en saison estivale et hivernale. Dans ce contexte, le CNERIB a construit et instrumenté deux bâtisses en BTC, en vue de décrire leur comportement thermique d’été et d’hiver, vis-à-vis d’une sollicitation climatique extérieure représentative de la région Nord du pays. Cette investigation a nécessité de mettre en place une chaîne de métrologie pour la collecte de mesures in situ. Dans cet article, le comportement thermique de ces deux bâtisses est décrit et les paramètres de l’inertie thermique des parois de mur en BTC déterminés. Les investigations menées ont montré qu’une construction réalisée en mur homogène (sans isolant) peut aisément satisfaire les conditions passives pour les besoins de chauffage et de rafraîchissement, ce qui peut constituer une solution garante d’économies d’énergie et de respect de l’environnement

Separation of blended data by iterative estimation and subtraction of interference noise

Conventional data acquisition practice dictates the existence of sufficient time intervals between the firing of successive sources in the field. However, much attention has been drawn recently to the possibility of shooting in an overlapping fash- ion. Numerous publications have addressed the issue from dif- ferent scopes (denoising, compressing, blind signal separation etc.) while others have defined the theoretical background. The term ‘blending’ was introduced to describe this new trend in acquisition designs, the time-overlapping data acquisition. In turn, the term ‘deblending’ refers to an algorithm that re- covers the data as if they were shot in the conventional way. Such an algorithm is presented in this chapter for application on both impulsive and vibrating sources. This algorithm is based on iterative interference estimation and subtraction and is applied to field data.GeotechnologyCivil Engineering and Geoscience

Towards host-directed therapies for tuberculosis

The treatment of tuberculosis is based on combinations of drugs that directly target Mycobacterium tuberculosis. A new global initiative is now focusing on a complementary approach of developing adjunct host-directed therapies. Despite the availability of effective antibiotics for tuberculosis (TB) for the past half century, it remains an important global health problem; there are ~9 million active TB cases and ~1.5 million TB-induced deaths per year (see the World Health Organization (WHO) Global Tuberculosis Report in Further information). Health services around the world face major barriers to achieving optimal outcomes from current TB treatment regimens. These barriers include: the spread of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB); complex and toxic treatment regimens for MDR-TB; HIV co-infection; pharmacokinetic interactions between TB drugs and antiretroviral drugs; relapse; permanent damage to lung and other tissues; long-term functional disability; immune reconstitution inflammatory syndrome (IRIS); and co-morbidity with non-communicable diseases such as diabetes and chronic obstructive airway diseases. Another fundamental problem is the long duration of TB drug treatment (6 months for drug-sensitive TB and at least 18 months for drug-resistant TB) to achieve a cure, owing to the presence of dormant Mycobacterium tuberculosis bacilli that are phenotypically resistant to current classes of anti-TB drugs, which can only target bacterial replication. There is therefore an urgent need for new TB treatments. However, the TB drug pipeline is thin1, 2. For the past 60 years, efforts to develop new treatments have focused on compounds and regimens that target M. tuberculosis directly. Recently, however, attention has focused on investigating a range of adjunct treatment interventions known as host-directed therapies (HDTs) that instead target the host response to infection. Here, we highlight the rationale for HDTs, the current portfolio of HDTs and their mechanisms of action, and a consortium-based approach to drive forward their evaluation in clinical trials

Formulation and characterization of self compacting concrete with silica fume

Self-compacting concrete (SCC) was elaborated using local materials and silica fume (SF) as admixture in 15% of cement quantity, two different Portland cements (PC) and two different superplasticizer that the chemical nature is polycarboxylate and plynaphtalene, the aggregates used are (AG 3/8 mm, AG 8/15 mm), coarse and fine sand (SC, SF) witch fineness modulus 3.2 and 1 in the order. The dosage of the different superplasticizer used is chosen after experimental spreading tests of each self compacting concrete formulation. Results of fresh concrete tests executed, as L-box and segregation resistance are on concordance whit values recommended by the French association of civil engendering. Also the mechanical characterization was conducted by compressive strength and splitting compression testing procedure, results values are in the range higher than 20 Mpa at the seven day by the compressive test for the all compositions, and the highest value was 40.93 MPa at the 28 day bay compressive test of the fourth’s formulation specimens, the values of splitting compressive tests of al formulation specimens at 7, 14 and 28 days, was situated between 2.01 and 4.40 MPa. In order to determine the superplasticizer saturation assay in of cement pasts used in self compacting concrete, the stady was completed by a rheological stady with a variable velocity gradient, so as to estimate the quantity of saturation assay of superplasticizer and the formulation, also the flow models of cement past

HIV gp120 in the lungs of antiretroviral therapy–treated Individuals impairs alveolar macrophage responses to pneumococci

Rationale People living with HIV (PLWH) are at significantly increased risk of invasive pneumococcal disease, despite long-term antiretroviral therapy (ART). The mechanism explaining this observation remains undefined. Objectives We hypothesized apoptosis-associated microbicidal mechanisms, required to clear intracellular pneumococci that survive initial phagolysosomal killing, are perturbed. Methods Alveolar macrophages (AM) were obtained by bronchoalveolar lavage (BAL) from healthy donors or HIV-1-seropositive donors on long-term ART with undetectable plasma viral load. Monocyte-derived macrophages (MDM) were obtained from healthy donors and infected with HIV-1BaL or treated with gp120. Macrophages were challenged with opsonized serotype 2 Streptococcus pneumoniae and assessed for apoptosis, bactericidal activity, protein expression and mitochondrial reactive oxygen species (mROS). AM phenotyping, ultra-sensitive HIV-1 RNA quantification and gp120 measurement were also performed in BAL. Measurements and Main Results HIV-1BaL infection impaired apoptosis, induction of mROS and pneumococcal killing by MDM. Apoptosis-associated pneumococcal killing was also reduced in AM from ART treated HIV-1-seropositive donors. BAL fluid from these individuals demonstrated persistent lung CD8+ T-cell lymphocytosis, and gp120 or HIV-1 RNA was also detected. Despite this, transcriptional activity in AM freshly isolated from PLWH was broadly similar to healthy volunteers. Instead, gp120 phenocopied the defect in pneumococcal killing in healthy MDM through post-translational modification of Mcl-1, preventing apoptosis induction, caspase activation and increased mROS generation. Moreover gp120 also inhibited mROS dependent pneumococcal killing in MDM. Conclusions. Despite ART, HIV-1, via gp120, drives persisting innate immune defects in AM microbicidal mechanisms, enhancing susceptibility to pneumococcal disease

Optical Properties of Highly Conductive SrMoO₃ Oxide Thin Films in the THz Band and Beyond

Strontium molybdate (SrMoO₃) thin films are grown epitaxially by pulsed laser deposition onto gadolinium scandate (GdScO₃) substrates and characterized in the terahertz (THz) and visible part of the electromagnetic spectrum. X-ray diffraction measurements prove a high crystallinity and phase-pure growth of the thin films. The high-quality SrMoO₃ thin films feature a room temperature DC conductivity of around 3 1/μΩm. SrMoO₃ is characterized in the THz frequency range by time domain spectroscopy. The resulting AC conductivity is in excellent agreement with the DC value. A Lorentz-Drude oscillator approach models the THz and visible conductivity of SrMoO₃ very well. We compare the results of the SrMoO₃ thin films to a standard, sputtered gold film, with a resulting THz conductivity of 8 1/μΩm. The comparison demonstrates that oxide thin film–based devices can play an important role in future THz technology

A G1-like state allows HIV-1 to bypass SAMHD1 restriction in macrophages.

An unresolved question is how HIV-1 achieves efficient replication in terminally differentiated macrophages despite the restriction factor SAMHD1. We reveal inducible changes in expression of cell cycle-associated proteins including MCM2 and cyclins A, E, D1/D3 in macrophages, without evidence for DNA synthesis or mitosis. These changes are induced by activation of the Raf/MEK/ERK kinase cascade, culminating in upregulation of CDK1 with subsequent SAMHD1 T592 phosphorylation and deactivation of its antiviral activity. HIV infection is limited to these G1-like phase macrophages at the single-cell level. Depletion of SAMHD1 in macrophages decouples the association between infection and expression of cell cycle-associated proteins, with terminally differentiated macrophages becoming highly susceptible to HIV-1. We observe both embryo-derived and monocyte-derived tissue-resident macrophages in a G1-like phase at frequencies approaching 20%, suggesting how macrophages sustain HIV-1 replication in vivo Finally, we reveal a SAMHD1-dependent antiretroviral activity of histone deacetylase inhibitors acting via p53 activation. These data provide a basis for host-directed therapeutic approaches aimed at limiting HIV-1 burden in macrophages that may contribute to curative interventions

Hyaluronidase treatment of synovial fluid is required for accurate detection of inflammatory cells and soluble mediators

Background Synovial fluid (SF) is commonly used for diagnostic and research purposes, as it is believed to reflect the local inflammatory environment. Owing to its complex composition and especially the presence of hyaluronic acid, SF is usually viscous and non-homogeneous. In this study, we investigated the importance of homogenization of the total SF sample before subsequent analysis. Methods SF was obtained from the knee of 29 arthritis patients (26 rheumatoid arthritis, 2 osteoarthritis, and 1 juvenile idiopathic arthritis patient) as part of standard clinical care. Synovial fluid was either treated with hyaluronidase as a whole or after aliquoting to determine whether the concentration of soluble mediators is evenly distributed in the viscous synovial fluid. Cytokine and IgG levels were measured by ELISA or Luminex and a total of seven fatty acid and oxylipin levels were determined using LC-MS/MS in all aliquots. For cell analysis, synovial fluid was first centrifuged and the pellet was separated from the fluid. The fluid was subsequently treated with hyaluronidase and centrifuged to isolate remaining cells. Cell numbers and phenotype were determined using flow cytometry. Results In all patients, there was less variation in IgG, 17-HDHA, leukotriene B-4 (LTB4), and prostaglandin E-2 (PGE(2)) levels when homogenization was performed before aliquoting the SF sample. There was no difference in variation for cytokines, 15-HETE, and fatty acids arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Between 0.8 and 70% of immune cells (median 5%) remained in suspension and were missing in subsequent analyses when the cells were isolated from untreated SF. This percentage was higher for T and B cells: 7-85% (median 22%) and 7-88% (median 23 %), respectively. Conclusions Homogenization of the entire SF sample leads to less variability in IgG and oxylipin levels and prevents erroneous conclusions based on incomplete isolation of synovial fluid cells.Orthopaedics, Trauma Surgery and Rehabilitatio