Justification of binder material selection for carbon particles incorporation into fibrous electromagnetic radiation absorber

The paper presents justification of a binder material for incorporating carbon particles into the interfiber space of electromagnetic radiation absorber. A method for carbon particles incorporation into a fibrous material has been developed. It is based on applying a carbon-containing nanocomposite to the fibrous material’s surface. Previously, the research of carbon particles incorporation into a synthetic material by using an aqueous solution were carried out, which ensured a uniform distribution of carbon particles in the material structure. However, the properties of the material have changed significantly upon mechanical deformation. Therefore, the carbon particles incorporation process was investigated using various nanocomposites obtained on the basis of mixtures of vinyl acetate polymer, or epoxy polymer, or surface-active substance with carbon black. Based on the results of electron microscopic analysis and the reflection and transmission coefficients frequency dependences in the frequency range 0.7–17 GHz, the efficiency of using a nanocomposite based on a mixture of surface-active substance and carbon black to create electromagnetic radiation absorbers was justified. Such electromagnetic radiation absorbers have the transmission coefficient value about –18 dB and reflection coefficient value about –12 dB in the frequency range 7–13 GHz. Carbon-containing electromagnetic radiation absorbers based on fibrous material have thickness less than 3 mm, properties of flexibility and resistance to mechanical deformation. It can be used in various fields, in particular for hiding objects from radio frequency reconnaissance or protecting equipment from external interference.The paper presents justification of a binder material for incorporating carbon particles into the interfiber space of electromagnetic radiation absorber. A method for carbon particles incorporation into a fibrous material has been developed. It is based on applying a carbon-containing nanocomposite to the fibrous material’s surface. Previously, the research of carbon particles incorporation into a synthetic material by using an aqueous solution were carried out, which ensured a uniform distribution of carbon particles in the material structure. However, the properties of the material have changed significantly upon mechanical deformation. Therefore, the carbon particles incorporation process was investigated using various nanocomposites obtained on the basis of mixtures of vinyl acetate polymer, or epoxy polymer, or surface-active substance with carbon black. Based on the results of electron microscopic analysis and the reflection and transmission coefficients frequency dependences in the frequency range 0.7–17 GHz, the efficiency of using a nanocomposite based on a mixture of surface-active substance and carbon black to create electromagnetic radiation absorbers was justified. Such electromagnetic radiation absorbers have the transmission coefficient value about –18 dB and reflection coefficient value about –12 dB in the frequency range 7–13 GHz. Carbon-containing electromagnetic radiation absorbers based on fibrous material have thickness less than 3 mm, properties of flexibility and resistance to mechanical deformation. It can be used in various fields, in particular for hiding objects from radio frequency reconnaissance or protecting equipment from external interference

Factors associated with unfavourable treatment outcomes among people with rifampicin-resistant tuberculosis in Armenia, 2014-2017.

Rifampicin-Resistant/Multidrug-Resistant Tuberculosis (RR/MDR-TB) is recognized as a major public health concern globally. In Armenia, the proportion of RR/MDR-TB is increasing among all people affected with TB. We conducted a nationwide cohort study involving analysis of programmatic data to investigate the rates of and factors associated with unfavourable treatment outcomes among patients with RR/MDR-TB registered by the national TB programme from 2014 to 2017 in Armenia. We used Cox regression to identify factors associated with the outcome. Among 451 RR/MDR-TB patients, 80% were men and median age was 46 years. Of them, 53 (11.8%) had Extensively Drug-Resistant Tuberculosis (XDR-TB) and 132 (29.3%) had pre-XDR-TB. Almost half (224, 49.7%) of the patients had unfavourable treatment outcome, which included 26.8% Loss To Follow-Up (LTFU), 13.3% failures and 9.5% deaths. In multivariable analysis, people with pre-XDR-TB [adjusted Hazard Ratio [aHR] 3.13, 95% confidence intervals [CI] 2.16-4.55] and XDR-TB (aHR 4.08, 95% CI 2.45-6.79) had a higher risk of unfavourable outcomes. Patients receiving home-based treatment (71/451, 15.7%) and treatment with new drugs (172/451, 38.1%) had significantly lower risk (aHR 0.45, 95% CI 0.28-0.72 and aHR 0.26, 95% CI 0.18-0.39) of unfavourable treatment outcome. The proportion of MDR-TB patients reaching favourable treatment outcome in Armenia was substantially lower than the recommended level (75%). The most common treatment outcome was LTFU indicating the need for further assessment of underlying determinants. Home-based treatment looks promising and future studies are required to see if expanding it to all RR/MDR-TB patients is feasible and cost-effective

Incidence of HIV and hepatitis C virus among people who inject drugs, and associations with age and sex or gender: a global systematic review and meta-analysis

Background: Measuring the incidence of HIV and hepatitis C virus (HCV) infection among people who inject drugs (PWID) is key to track progress towards elimination. We aimed to summarise global data on HIV and primary HCV incidence among PWID and associations with age and sex or gender. Methods: In this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies among PWID by searching MEDLINE, Embase, and PsycINFO, capturing studies published between Jan 1, 2000, and Dec 12, 2022, with no language or study design restrictions. We contacted authors of identified studies for unpublished or updated data. We included studies that estimated incidence by longitudinally re-testing people at risk of infection or by using assays for recent infection. We pooled incidence and relative risk (RR; young [generally defined as ≤25 years] vs older PWID; women vs men) estimates using random-effects meta-analysis and assessed risk of bias with a modified Newcastle–Ottawa scale. This study is registered with PROSPERO, CRD42020220884. Findings: Our updated search identified 9493 publications, of which 211 were eligible for full-text review. An additional 377 full-text records from our existing database and five records identified through cross-referencing were assessed. Including 28 unpublished records, 125 records met the inclusion criteria. We identified 64 estimates of HIV incidence (30 from high-income countries [HICs] and 34 from low-income or middle-income countries [LMICs]) and 66 estimates of HCV incidence (52 from HICs and 14 from LMICs). 41 (64%) of 64 HIV and 42 (64%) of 66 HCV estimates were from single cities rather than being multi-city or nationwide. Estimates were measured over 1987–2021 for HIV and 1992–2021 for HCV. Pooled HIV incidence was 1·7 per 100 person-years (95% CI 1·3–2·3; I2=98·4%) and pooled HCV incidence was 12·1 per 100 person-years (10·0–14·6; I2=97·2%). Young PWID had a greater risk of HIV (RR 1·5, 95% CI 1·2–1·8; I2=66·9%) and HCV (1·5, 1·3–1·8; I2=70·6%) acquisition than older PWID. Women had a greater risk of HIV (RR 1·4, 95% CI 1·1–1·6; I2=55·3%) and HCV (1·2, 1·1–1·3; I2=43·3%) acquisition than men. For both HIV and HCV, the median risk-of-bias score was 6 (IQR 6–7), indicating moderate risk. Interpretation: Although sparse, available HIV and HCV incidence estimates offer insights into global levels of HIV and HCV transmission among PWID. Intensified efforts are needed to keep track of the HIV and HCV epidemics among PWID and to expand access to age-appropriate and gender-appropriate prevention services that serve young PWID and women who inject drugs. Funding: Canadian Institutes of Health Research, Fonds de recherche du Québec–Santé, Canadian Network on Hepatitis C, UK National Institute for Health and Care Research, and WHO

Justification of binder material selection for carbon particles incorporation into fibrous electromagnetic radiation absorber

The paper presents justification of a binder material for incorporating carbon particles into the interfiber space of electromagnetic radiation absorber. A method for carbon particles incorporation into a fibrous material has been developed. It is based on applying a carbon-containing nanocomposite to the fibrous material’s surface. Previously, the research of carbon particles incorporation into a synthetic material by using an aqueous solution were carried out, which ensured a uniform distribution of carbon particles in the material structure. However, the properties of the material have changed significantly upon mechanical deformation. Therefore, the carbon particles incorporation process was investigated using various nanocomposites obtained on the basis of mixtures of vinyl acetate polymer, or epoxy polymer, or surface-active substance with carbon black. Based on the results of electron microscopic analysis and the reflection and transmission coefficients frequency dependences in the frequency range 0.7–17 GHz, the efficiency of using a nanocomposite based on a mixture of surface-active substance and carbon black to create electromagnetic radiation absorbers was justified. Such electromagnetic radiation absorbers have the transmission coefficient value about –18 dB and reflection coefficient value about –12 dB in the frequency range 7–13 GHz. Carbon-containing electromagnetic radiation absorbers based on fibrous material have thickness less than 3 mm, properties of flexibility and resistance to mechanical deformation. It can be used in various fields, in particular for hiding objects from radio frequency reconnaissance or protecting equipment from external interference

Justification of binder material selection for carbon particles incorporation into fibrous electromagnetic radiation absorber

The paper presents justification of a binder material for incorporating carbon particles into the interfiber space of electromagnetic radiation absorber. A method for carbon particles incorporation into a fibrous material has been developed. It is based on applying a carbon-containing nanocomposite to the fibrous material’s surface. Previously, the research of carbon particles incorporation into a synthetic material by using an aqueous solution were carried out, which ensured a uniform distribution of carbon particles in the material structure. However, the properties of the material have changed significantly upon mechanical deformation. Therefore, the carbon particles incorporation process was investigated using various nanocomposites obtained on the basis of mixtures of vinyl acetate polymer, or epoxy polymer, or surface-active substance with carbon black. Based on the results of electron microscopic analysis and the reflection and transmission coefficients frequency dependences in the frequency range 0.7–17 GHz, the efficiency of using a nanocomposite based on a mixture of surface-active substance and carbon black to create electromagnetic radiation absorbers was justified. Such electromagnetic radiation absorbers have the transmission coefficient value about –18 dB and reflection coefficient value about –12 dB in the frequency range 7–13 GHz. Carbon-containing electromagnetic radiation absorbers based on fibrous material have thickness less than 3 mm, properties of flexibility and resistance to mechanical deformation. It can be used in various fields, in particular for hiding objects from radio frequency reconnaissance or protecting equipment from external interference

Preferences and decisional considerations relating to opioid agonist therapy among Ukrainian people who use drugs: A conjoint analysis survey.

Scaling up opioid agonist therapies (OAT) is the most effective strategy to control combined HIV and opioid epidemics, especially in Eastern Europe and Central Asia (EECA), where HIV incidence and mortality continue to increase. Patient concerns about OAT, however, have undermined scale-up. The objective of this study is to understand Ukrainian opioid use disorder patient preferences about OAT to guide the development of an evidence-informed decision aid for clinical decision-making. We conducted a conjoint-based choice (CBC) survey. Participants were asked to about their preferences relating to 7 attributes of OAT (cost, dosing frequency, concerns about withdrawal symptoms, adverse side effects, improvements in quality of life, precipitation of withdrawal and legislative requirements to be registered as a drug dependent person) and 20 attribute levels for receiving OAT under differing potential treatment constraints. Data were analyzed using Hierarchical Bayesian models. Using respondent-driven sampling and random sampling, we recruited 2,028 people who inject drugs with opioid use disorder. Relative importance (RIS) and partial-worth utility scores (PWUS) were used to assess preferences for attributes and thresholds within each attribute. Cost and dosing frequency were the most important attributes (RIS = 39.2% and RIS = 25.2%, respectively) to potential patients, followed by concerns about withdrawal symptoms (RIS = 10.8%), adverse side effects (RIS = 9.0%), quality-of-life improvement (RIS = 7.5%), precipitation of euphoria (5.2%) and requirement to be registered as a drug- dependent person (RIS = 3.1%). The monthly cost-threshold for willingness-to-pay was 1,900 UAH ($70 USD). In Ukraine, where both governmental and private OAT clinics have emerged and provide markedly different delivery strategies, preferences are mostly driven by out-of-pocket expenses, despite many patients being willing to pay for OAT. Programmatic demands (flexibility and ease of acquiring medications) remain an important consideration while for a minority, clinical concerns about withdrawal symptoms, adverse side effects and OAT impact on life play a smaller role