Observation of anisotropic Dirac cones in the topological material Ti2Te2P

Anisotropic bulk Dirac (or Weyl) cones in three dimensional systems have recently gained intense research interest as they are examples of materials with tilted Dirac (or Weyl) cones indicatig the violation of Lorentz invariance. In contrast, the studies on anisotropic surface Dirac cones in topological materials which contribute to anisotropic carrier mobility have been limited. By employing angle-resolved photoemission spectroscopy and first-principles calculations, we reveal the anisotropic surface Dirac dispersion in a tetradymite material Ti2Te2P on the (001) plane of the Brillioun zone. We observe the quasi-elliptical Fermi pockets at the M -point of the Brillouin zone forming the anisotropic surface Dirac cones. Our calculations of the Z2 indices confirm that the system is topologically non-trivial with multiple topological phases in the same material. In addition, the observed nodal-line like feature formed by bulk bands makes this system topologically rich.Comment: 21 pages, 17 figures, Supplementary Information include

A humid electronic nose based on pulse voltammetry: A proof-of-concept design

[EN] We report herein the design, manufacture and use of a "humid electronic nose" prototype based on voltammetric techniques. It consists of an array of four working electrodes (i.e., Au, Pt, Ir and Rh) housed inside a homemade stainless steel cylinder, in contact with a fabric mesh made of nylon damped with a NaCl aqueous solution, used as the supporting humid membrane. The "humid electronic nose" was tested for the discrimination of different samples displaying different volatile compounds. The samples chosen involve aqueous solutions of different simple volatile products (i.e., ammonia, acetone, acetic acid and 6-amino-1-hexanol) and different food samples (i.e., onion, coffee and Roquefort cheese). Under working conditions, the volatile compounds from the corresponding sample were generated in the measurement chamber and were partially dissolved in the damped nylon fabric, which was in contact with the set of electrodes. It was envisioned that provided different samples offer different vapours, the application of a suitable set of pulses to the electrodes will differentiate the samples. This proof-of-concept study employed a Large Amplitude Pulse Voltammetry (LAPV) waveform. The increment for the potential steps was of 200 mV and potentials ranged from +1 to -1 V with each pulse applied for 50 ms. PCA studies from the response obtained by the "humid electronic nose" discriminated the different samples studied. The neural network Self Organized Map (SOM) was also used to analyze the electrochemical data obtained from the "humid electronic nose". © 2013 Elsevier B.VThe financial support from the Spanish Government (project MAT2012-38429-C04) and the Generalitat Valenciana (Valencian Regional Government; projects PROMETEO/2009/016 and GV/2012/094); is gratefully acknowledged.Bataller Prats, R.; Campos Sánchez, I.; Alcañiz Fillol, M.; Gil Sánchez, L.; García Breijo, E.; Martínez Mañez, R.; Pascual Vidal, L.... (2013). A humid electronic nose based on pulse voltammetry: A proof-of-concept design. Sensors and Actuators B: Chemical. 186:666-673. https://doi.org/10.1016/j.snb.2013.06.033S66667318

The Cost of Providing Comprehensive HIV Services to Key Populations : An Analysis of the LINKAGES Program in Kenya and Malawi

Introduction: Timely data on HIV service costs are critical for estimating resource needs and allocating funding, but few data exist on the cost of HIV services for key populations (KPs) at higher risk of HIV infection in low- and middle-income countries. We aimed to estimate the total and per contact annual cost of providing comprehensive HIV services to KPs to inform planning and budgeting decisions. Methods: We collected cost data from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV (LINKAGES) program in Kenya and Malawi serving female and male sex workers, men who have sex with men, and transgender women. Data were collected prospectively for fiscal year (FY) 2019 and retrospectively for start-up activities conducted in FY2015 and FY2016. Data to estimate economic costs from the provider’s perspective were collected from LINKAGES headquarters, country offices, implementing partners (IPs), and drop-in centers (DICs). We used top-down and bottom-up cost estimation approaches. Results: Total economic costs for FY2019 were US$6,175,960 in Kenya and US$4,261,207 in Malawi. The proportion of costs incurred in IPs and DICs was 66% in Kenya and 42% in Malawi. The costliest program areas were clinical services, management, peer outreach, and monitoring and data use. Mean cost per contact was US$127 in Kenya and US$279 in Malawi, with a mean cost per contact in DICs and IPs of US$63 in Kenya and US$104 in Malawi. Conclusion: Actions undertaken above the service level in headquarters and country offices along with those conducted below the service level in communities, comprised important proportions of KP HIV service costs. The costs of pre-service population mapping and size estimation activities were not negligible. Costing studies that focus on the service level alone are likely to underestimate the costs of delivering HIV services to KPs

Predictors of Hospitalized Exacerbations and Mortality in Chronic Obstructive Pulmonary Disease

Background and Aim Exacerbations of chronic obstructive pulmonary disease (COPD) carry significant consequences for patients and are responsible for considerable health-care costs?particularly if hospitalization is required. Despite the importance of hospitalized exacerbations, relatively little is known about their determinants. This study aimed to analyze predictors of hospitalized exacerbations and mortality in COPD patients. Methods This was a retrospective population-based cohort study.We selected 900 patients with confirmed COPD aged 35 years by simple random sampling among all COPD patients in Cantabria (northern Spain) on December 31, 2011. We defined moderate exacerbations as events that led a care provider to prescribe antibiotics or corticosteroids and severe exacerbations as exacerbations requiring hospital admission.We observed exacerbation frequency over the previous year (2011) and following year (2012). We categorized patients according to COPD severity based on forced expiratory volume in 1 second (Global Initiative for Chronic Obstructive Lung Disease [GOLD] grades 1?4). We estimated the odds ratios (ORs) by logistic regression, adjusting for age, sex, smoking status, COPD severity, and frequent exacerbator phenotype the previous year. Results Of the patients, 16.4%had 1 severe exacerbations, varying from 9.3%in mild GOLD grade 1 to 44%in very severe COPD patients. A history of at least two prior severe exacerbations was positively associated with new severe exacerbations (adjusted OR, 6.73; 95%confidence interval [CI], 3.53?12.83) and mortality (adjusted OR, 7.63; 95%CI, 3.41?17.05). Older age and several comorbidities, such as heart failure and diabetes, were similarly associated. Conclusions Hospitalized exacerbations occurred with all grades of airflow limitation. A history of severe exacerbations was associated with new hospitalized exacerbations and mortality

Intensification of Antiretroviral Therapy with a CCR5 Antagonist in Patients with Chronic HIV-1 Infection: Effect on T Cells Latently Infected

Objective: The primary objective was to assess the effect of MVC intensification on latently infected CD4+ T cells in chronically HIV-1-infected patients receiving antiretroviral therapy. Methods: We performed an open-label pilot phase II clinical trial involving chronically HIV-1-infected patients receiving stable antiretroviral therapy whose regimen was intensified with 48 weeks of maraviroc therapy. We analyzed the latent reservoir, the residual viremia and episomal 2LTR DNA to examine the relationship between these measures and the HIV-1 latent reservoir, immune activation, lymphocyte subsets (including effector and central memory T cells), and markers associated with bacterial translocation. Results: Overall a non significant reduction in the size of the latent reservoir was found (p = 0.068). A mean reduction of 1.82 IUPM was observed in 4 patients with detectable latent reservoir at baseline after 48 weeks of intensification. No effect on plasma residual viremia was observed. Unexpectedly, all the patients had detectable 2LTR DNA circles at week 24, while none of them showed those circles at the end of the study. No changes were detected in CD4+ or CD8+ counts, although a significant decrease was found in the proportion of HLA-DR+/CD38+ CD4+ and CD8+ T-cells. LPS and sCD14 levels increased. Conclusions: Intensification with MVC was associated with a trend to a decrease in the size of the latent HIV-1 reservoir in memory T cells. No impact on residual viremia was detected. Additional studies with larger samples are needed to confirm the results

The use of plants in the traditional management of diabetes in Nigeria: Pharmacological and toxicological considerations

Ethnopharmacological relevance: The prevalence of diabetes is on a steady increase worldwide and it is now identified as one of the main threats to human health in the 21st century. In Nigeria, the use of herbal medicine alone or alongside prescription drugs for its management is quite common. We hereby carry out a review of medicinal plants traditionally used for diabetes management in Nigeria. Based on the available evidence on the species׳ pharmacology and safety, we highlight ways in which their therapeutic potential can be properly harnessed for possible integration into the country׳s healthcare system. Materials and methods: Ethnobotanical information was obtained from a literature search of electronic databases such as Google Scholar, Pubmed and Scopus up to 2013 for publications on medicinal plants used in diabetes management, in which the place of use and/or sample collection was identified as Nigeria. ‘Diabetes’ and ‘Nigeria’ were used as keywords for the primary searches; and then ‘Plant name – accepted or synonyms’, ‘Constituents’, ‘Drug interaction’ and/or ‘Toxicity’ for the secondary searches. Results: The hypoglycemic effect of over a hundred out of the 115 plants reviewed in this paper is backed by preclinical experimental evidence, either in vivo or in vitro. One-third of the plants have been studied for their mechanism of action, while isolation of the bioactive constituent(s) has been accomplished for twenty three plants. Some plants showed specific organ toxicity, mostly nephrotoxic or hepatotoxic, with direct effects on the levels of some liver function enzymes. Twenty eight plants have been identified as in vitro modulators of P-glycoprotein and/or one or more of the cytochrome P450 enzymes, while eleven plants altered the levels of phase 2 metabolic enzymes, chiefly glutathione, with the potential to alter the pharmacokinetics of co-administered drugs. Conclusion: This review, therefore, provides a useful resource to enable a thorough assessment of the profile of plants used in diabetes management so as to ensure a more rational use. By anticipating potential toxicities or possible herb–drug interactions, significant risks which would otherwise represent a burden on the country׳s healthcare system can be avoided