Ferroelectric Domain Wall Warp Memristor.

Domain walls are quasi-one-dimensional topological defects in ferroic materials, which can harbor emergent functionalities. In the case of ferroelectric domain wall (FEDW) devices, an exciting frontier has emerged: memristor-based information storage and processing approaches. Memristor solid-state FEDW devices presented thus far, however predominantly utilize a complex network of domain walls to achieve the desired regulation of density and charge state.

Effect of high-dose multivitamin supplements on alanine aminotransferase elevations among adults living with HIV on antiretroviral therapy in Tanzania.

Background: HIV infection can cause malabsorption and rapid utilization of nutrients. A randomized trial of multivitamin supplementation among people living with HIV/AIDS (PLWHA) initiating antiretroviral therapy (ART) in Tanzania was stopped early due to increased alanine aminotransferase (ALT) concentrations in the multiple recommended dietary allowances (RDA) multivitamin group. We conducted detailed analysis to assess the effect of multivitamins on ALT elevations and evaluate whether subgroups of PLWHA have greater hepatotoxicity risks associated with the use of high-dose multivitamins.

Trends and correlates in HIV viral load monitoring and viral suppression among adolescents and young adults in Dar es Salaam, Tanzania.

Background: Adolescents and young adults (AYA) living with HIV have been shown to have lower rates of viral load testing and viral suppression as compared to older adults. We examined trends over time and predictors of HIV viral load monitoring and viral suppression among AYA in a large HIV treatment programme in Dar es Salaam, Tanzania.

Methods: We analysed longitudinal data of AYA aged 10-24 years initiated on antiretroviral therapy between January 2017 and October 2022.

School health and nutrition services for children and adolescents in Tanzania: A review of policies and programmes.

School health and nutrition programmes are effective strategies to address the health problems among school-going children and adolescents. We examined the policy environments, successes and bottlenecks associated with school health and nutrition programmes in Tanzania. We used the 'policy triangle framework' to examine 22 national and regional school health and nutrition policies and programmes in Tanzania.

Resistance-informed versus empirical management of viraemia in children and adolescents with HIV in Lesotho and Tanzania (GIVE MOVE trial): a multisite, open-label randomised controlled trial.

Background: Children and adolescents with HIV taking antiretroviral therapy (ART) have high rates of viraemia. We assessed if genotypic resistance testing (GRT) to inform onward treatment improved treatment outcomes in Lesotho and Tanzania, two countries with little access to GRT.

Methods: The Genotype-Informed Versus Empirical Management of Viremia (GIVE MOVE) open-label, parallel-group randomised controlled trial enrolled children and adolescents with HIV between the ages of 6 months and 19 years, taking ART, and with a viral load at least 400 copies per mL.

Demonstrating service delivery models for effective initiation and retention on pre-exposure prophylaxis (PrEP) among female bar workers in Dar es Salaam, Tanzania: A double randomized intervention study protocol.

Background: Pre-Exposure Prophylaxis (PrEP) has demonstrated efficacy in preventing HIV infection. Female Bar Workers (FBWs) often act as informal sex workers, placing them at risk of HIV infection. Despite expressing interest in PrEP, FBWs face barriers to accessing public-sector clinics where PrEP is delivered.

Accelerating COVID-19 Vaccination Among People Living With HIV and Health Care Workers in Tanzania: A Case Study.

Background: There is limited evidence on COVID-19 vaccination uptake among people living with HIV (PLHIV) and health care workers (HCWs), with the current evidence concentrated in high-income countries. There is also limited documentation in the published literature regarding the feasibility and lessons from implementing targeted vaccination strategies to reach PLHIV and HCWs in low- and middle-income countries.

Program Development, Piloting, And Implementation: We designed and implemented multifaceted strategies to scale up targeted COVID-19 vaccination among PLHIV and HCWs in 11 administrative regions on the mainland of Tanzania plus Zanzibar.

Anemia and Iron Supplementation in Relation to Viral Load and Mortality among 70,442 People Living with Human Immunodeficiency Virus in Tanzania.

Background: Anemia may be associated with poor clinical outcomes among people living with human immunodeficiency virus (HIV) (PLHIV) despite highly active antiretroviral therapy (HAART). There are concerns that iron supplementation may be unsafe to prevent and treat anemia among PLHIV.

Objective: The objective of the study was to evaluate the associations of anemia and iron supplementation with mortality and viral load among PLHIV in Tanzania.

Engineering Domain Variants in 0.7Pb(MgNb)-0.3PbTiO Single Crystals Using High-Frequency AC Poling.

Single crystals of (001)-oriented 0.7Pb(MgNb)-0.3PbTiO (PMN-30PT) with a composition near the morphotropic phase boundary have attracted considerable attention due to their superior dielectric and electromechanical performance.

Long-term retention on antiretroviral treatment after enrolment in prevention of vertical HIV transmission services: a prospective cohort study in Dar es Salaam, Tanzania.

Introduction: To prevent vertical HIV transmission and ensure healthy mothers and children, pregnant women with HIV must remain on antiretroviral treatment (ART) for life. However, motivation to remain on ART may decline beyond the standard 2-year breastfeeding/postpartum period. We assessed attrition and retention in ART care among women with HIV up to 6 years since enrolment in vertical transmission prevention services in Dar es Salaam, Tanzania.

Magnetocapacitance at the Ni/BiInO Schottky Interface.

We report the observation of a magnetocapacitance effect at the interface between Ni and epitaxial nonpolar BiInO thin films at room temperature. A detailed surface study using X-ray photoelectron spectroscopy (XPS) reveals the formation of an intermetallic Ni-Bi alloy at the Ni/BiInO interface and a shift in the Bi 4f and In 3d core levels to higher binding energies with increasing Ni thickness. The latter infers band bending in BiInO, corresponding to the formation of a p-type Schottky barrier.

High viral suppression and detection of dolutegravir-resistance associated mutations in treatment-experienced Tanzanian adults living with HIV-1 in Dar es Salaam.

To curb HIV infection rate in Tanzania, antiretroviral therapy (ART) has been scaled up since 2006, and in 2019, the country shifted to regimen including dolutegravir as a default first line. We assessed the success of ART and the contribution of HIV drug resistance (HIVDR) to unsuppressed viral loads. Between February and May 2023 a cross-sectional survey with random sampling was conducted in the six clinics in an urban cohort in Dar es Salaam.

Temporal and spatial tracking of ultrafast light-induced strain and polarization modulation in a ferroelectric thin film.

Ultrashort light pulses induce rapid deformations of crystalline lattices. In ferroelectrics, lattice deformations couple directly to the polarization, which opens the perspective to modulate the electric polarization on an ultrafast time scale. Here, we report on the temporal and spatial tracking of strain and polar modulation in a single-domain BiFeO thin film by ultrashort light pulses.

Ferroelectric solitons crafted in epitaxial bismuth ferrite superlattices.

In ferroelectrics, complex interactions among various degrees of freedom enable the condensation of topologically protected polarization textures. Known as ferroelectric solitons, these particle-like structures represent a new class of materials with promise for beyond-CMOS technologies due to their ultrafine size and sensitivity to external stimuli. Such polarization textures have scarcely been demonstrated in multiferroics.

Effect of peer-mother interactive programme on prevention of mother-to-child HIV transmission outcomes among pregnant women on anti-retroviral treatment in routine healthcare in Dar es Salaam, Tanzania.

Peer support services are increasingly being integrated in programmes for the prevention of mother-to-child HIV transmission (PMTCT). We aimed to evaluate the effect of a peer-mother interactive programme on PMTCT outcomes among pregnant women on anti-retroviral treatment (ART) in routine healthcare in Dar es Salaam, Tanzania. Twenty-three health facilities were cluster-randomized to a peer-mother intervention and 24 to a control arm.

Effects of Multiple Local Environments on Electron Energy Loss Spectra of Epitaxial Perovskite Interfaces.

The role of local chemical environments in the electron energy loss spectra of complex multiferroic oxides was studied using computational and experimental techniques. The evolution of the O K-edge across an interface between bismuth ferrite (BFO) and lanthanum strontium manganate (LSMO) was considered through spectral averaging over crystallographically equivalent positions to capture the periodicity of the local O environments. Computational techniques were used to investigate the contribution of individual atomic environments to the overall spectrum, and the role of doping and strain was considered.

Vertical HIV transmission within 18 months post partum among women on lifelong antiretroviral therapy for HIV in Dar es Salaam, Tanzania: a prospective cohort study.

Background: The UNAIDS estimate of vertical HIV transmission in Tanzania is high (11%), despite 84% uptake of antiretroviral therapy (ART) among pregnant women with HIV. We aimed to evaluate vertical transmission and its determinants by 18 months post partum among women on lifelong ART in routine health-care settings in Tanzania.

Methods: We conducted a prospective cohort study in 226 health facitilies across Dar-es-Salaam, Tanzania.

The impact of a community health worker intervention on uptake of antenatal care: a cluster-randomized pragmatic trial in Dar es Salaam.

The provision of high-quality antenatal care (ANC) is important for preventing maternal and newborn mortality and morbidity, but only around half of pregnant women in Tanzania attended four or more ANC visits in 2019. Although there is emerging evidence on the benefit of community health worker (CHW) interventions on ANC uptake, few large-scale pragmatic trials have been conducted. This pragmatic cluster-randomized trial, implemented directly through the public sector health system, assessed the impact of an intervention that trained public sector CHWs to promote the uptake of ANC.

Re-evaluating the health impact and cost-effectiveness of tuberculosis preventive treatment for modern HIV cohorts on antiretroviral therapy: a modelling analysis using data from Tanzania.

Background: Isoniazid preventive therapy (IPT) can prevent tuberculosis among people receiving antiretroviral therapy (ART). HIV programmes are now initiating patients on ART with higher average CD4 cell counts and lower tuberculosis risks under test-and-treat guidelines. We aimed to investigate how this change has affected the health impact and cost-effectiveness of IPT.

A Room-Temperature Ferroelectric Resonant Tunneling Diode.

Resonant tunneling is a quantum-mechanical effect in which electron transport is controlled by the discrete energy levels within a quantum-well (QW) structure. A ferroelectric resonant tunneling diode (RTD) exploits the switchable electric polarization state of the QW barrier to tune the device resistance. Here, the discovery of robust room-temperature ferroelectric-modulated resonant tunneling and negative differential resistance (NDR) behaviors in all-perovskite-oxide BaTiO /SrRuO /BaTiO QW structures is reported.

Strain and orientation engineering in ABOperovskite oxide thin films.

Perovskite oxides with chemical formula ABOare widely studied for their properties including ferroelectricity, magnetism, strongly correlated physics, optical effects, and superconductivity. A thriving research direction using such materials is through their integration as epitaxial thin films, allowing many novel and exotic effects to be discovered. The integration of the thin film on a single crystal substrate, however, can produce unique and powerful effects, and can even induce phases in the thin film that are not stable in bulk.

Anisotropic epitaxial stabilization of a low-symmetry ferroelectric with enhanced electromechanical response.

Piezoelectrics interconvert mechanical energy and electric charge and are widely used in actuators and sensors. The best performing materials are ferroelectrics at a morphotropic phase boundary, where several phases coexist. Switching between these phases by electric field produces a large electromechanical response.