Abul K. Azad

Person-to-person transmission of Nipah virus in a Bangladeshi community.

Transmission of this virus highlights the need for infection control strategies for resource-poor settings.

Clinical Presentation of Nipah Virus Infection in Bangladesh

BACKGROUNDnIn Bangladesh, 4 outbreaks of Nipah virus infection were identified during the period 2001-2004.nnnMETHODSnWe characterized the clinical features of Nipah virus-infected individuals affected by these outbreaks. We classified patients as having confirmed cases of Nipah virus infection if they had antibodies reactive with Nipah virus antigen. Patients were considered to have probable cases of Nipah virus infection if they had symptoms consistent with Nipah virus infection during the same time and in the same community as patients with confirmed cases.nnnRESULTSnWe identified 92 patients with Nipah virus infection, 67 (73%) of whom died. Although all age groups were affected, 2 outbreaks principally affected young persons (median age, 12 years); 62% of the affected persons were male. Fever, altered mental status, headache, cough, respiratory difficulty, vomiting, and convulsions were the most common signs and symptoms; clinical and radiographic features of acute respiratory distress syndrome of Nipah illness were identified during the fourth outbreak. Among those who died, death occurred a median of 6 days (range, 2-36 days) after the onset of illness. Patients who died were more likely than survivors to have a temperature >37.8 degrees C, altered mental status, difficulty breathing, and abnormal plantar reflexes. Among patients with Nipah virus infection who had well-defined exposure to another patient infected with Nipah virus, the median incubation period was 9 days (range, 6-11 days).nnnCONCLUSIONSnNipah virus infection produced rapidly progressive severe illness affecting the central nervous and respiratory systems. Clinical characteristics of Nipah virus infection in Bangladesh, including a severe respiratory component, appear distinct from clinical characteristics reported during earlier outbreaks in other countries.

Structural origins of the differing grain conductivity values in BaZr0.9Y0.1O2.95 and indication of novel approach to counter defect association

Proton conducting oxides such as BaCe0.9Y0.1O3−δ have considerable promise for intermediate temperature fuel cells. Unfortunately these tend to be unstable, e.g. to attack by carbonation. Previous work has highlighted the possibility of utilising barium zirconate to provide a chemically stable electrolyte; however such materials are difficult to sinter yielding very high overall resistances. Whilst this sintering problem is soluble, there are still very significant questions about the intrinsic grain conductivity, which varies by orders of magnitude for different reports. Here we demonstrate that there are two variants of BaZr0.9Y0.1O2.95, both with the cubic perovskite structure. The α-form exhibits a slightly smaller unit cell and much lower protonic conductivity than the β-form. The α-form is observed in better equilibrated samples and neutron diffraction demonstrates that this difference originates in a small degree of cross substitution of the Y atom onto the A-sites for the β-form, suggesting a novel approach to enhance ionic conductivity by reducing defect association through A-site substitution.

Risk of nosocomial transmission of Nipah virus in a Bangladesh Hospital

We conducted a seroprevalence study and exposure survey of healthcare workers to assess the risk of nosocomial transmission of Nipah virus during an outbreak in Bangladesh in 2004. No evidence of recent Nipah virus infection was detected despite substantial exposures and minimal use of personal protective equipment.

Overview of a multi-stakeholder dialogue around Shared Services for Health: the Digital Health Opportunity in Bangladesh

BackgroundNational level policymaking and implementation includes multiple stakeholders with varied interests and priorities. Multi-stakeholder dialogues (MSDs) can facilitate consensus building through collective identification of challenges, recognition of shared goals and interests, and creation of solution pathways. This can shape joint planning and implementation for long-term efficiency in health and other sectors. Scaling up the effective use of information and communication technologies (ICTs) requires cohesive strategic planning towards a shared goal. In Bangladesh, the government and partners convened an MSD in March 2015 to increase stakeholder engagement in policymaking and implementation of a national ICT or electronic or mobile health (eHealth or mHealth) strategy, which seeks to incorporate ICTs into the national health system, aligning with the Digital Bangladesh Vision 2021.MethodsRelevant stakeholders were identified and key priorities and challenges were mapped through key informant interviews. An MSD was conducted with key stakeholders in Dhaka, Bangladesh. The MSD included presentations, group option generation, agreement and prioritization of barriers to scaling up ICTs.ResultsThe MSD approach to building consensus on key priorities highlights the value of dialogue and collaboration with relevant stakeholders to encourage country ownership of nationwide efforts such as ICT scale-up. This MSD showed the dynamic context in which stakeholders operate, including those from academia, donors and foundations, healthcare professionals, associations, multilateral organizations, non-governmental organizations, partner countries and the private sector. Through this MSD, participants improved understanding of each other’s contributions and interests, identified existing relationships, and agreed on policy and implementation gaps that needed to be filled. Collaboration among stakeholders in ICT efforts and research can promote a cohesive approach to scaling up, as well as improve policymaking by integrating interests and feedback of different key cross sectoral actors.ConclusionMSDs can align stakeholders to identify challenges and solution pathways, and lead to coordinated action and accountability for resources and results. In addition, the MSD template and approach has been useful to guide ICT scale up in Bangladesh and could be replicated in other contexts to facilitate multi-constituency, multi-sector collaboration.

Structure and properties of MgMxCr2−xO4 (M = Li, Mg, Ti, Fe, Cu, Ga) spinels for electrode supports in solid oxide fuel cells

Novel electrode scaffold materials based on chromium-rich spinels, such as MgMxCr2−xO4, (M = Li, Mg, Ti, Fe, Cu, Ga) have been investigated for solid oxide fuel cell (SOFC) applications, in terms of conductivity and chemical stability when operated in fuel environments. Cation distributions were obtained by Rietveld refinement from X-ray diffraction data (XRD), with cation site preference considered in agreement with literature, and correlated with electrical properties determined experimentally. The substitutions with cations such as Li and Cu on B site improved the conductivity of the materials in air, while introducing Fe and Ga in the structure led to a decrease in conductivity in air. However, Fe had a positive contribution under reducing conditions, generating a change in the conductivity mechanism from p-type in air, to n-type. Conductivity measurements indicated that MgFexCr2−xO4 spinels exhibit faster reduction kinetics, in comparison with other substituted cations at the B site which is desirable in fuel cell application, for a reasonably fast response of a cell or a stack to reach its full functional potential. MgFeCrO4 showed fast reduction kinetics, with increase of the conductivity in reducing conditions from 0.014 S cm−1 to 0.4 S cm−1 and equilibration time for reaching the maximum conductivity value of 10 hours, under dry 5% H2/Ar at 850 °C.

Remarkable transition from rocksalt/perovskite layered structure to fluorite/rocksalt layered structure in rapidly cooled Ln2CuO4

Lanthanide cuprates of formula Ln2CuO4 exist in two principal forms, T and T′ which are renowned for their exhibition at low temperatures of hole and electronic types of superconductivity, respectively. These structures differ primarily in the arrangement of oxygen between the perovskite layers and also in nature of the copper oxygen planes. The Cu-O distance in the T structure (~1.90 Å) is much shorter than the T′ (1.97Å), reflecting a transition between partial Cu+ and partial Cu3+ character. In seeking to find compositions that bridge these two structure/electron carrier types, we observed the transition from a T structure to a T′ type structure, resulting in the metastable form T″ with slightly larger volume but similar character to T′. This transition from T to T″ is associated with 5% increase in a and a 5% decrease in c parameters of the tetragonal unit cells, which results in disintegration of ceramic bodies.

Thermochemical characterisation of Acacia auriculiformis tree parts via proximate, ultimate, TGA, DTG, calorific value and FTIR spectroscopy analyses to evaluate their potential as a biofuel resource

ABSTRACT Continuously increasing energy requirements coupled with environmental pollution have established pressure to utilise lignocellulosic biomass for energy production. Acacia auriculiformis is a fast-growing species capable of accumulating large quantities of biomass without requiring major agricultural inputs. The aim of this research was to investigate the thermochemical properties of its tree parts including phyllodes (leaves), trunk, bark and branches to utilise them as solid fuel to produce bioenergy. Thermogravimetric and derivative thermogravimetric (TGA and DTG ) analyses were performed to study the biomass degradation behaviour, which showed the decomposition of biomass in three major stages corresponding to the decomposition of hemicellulose, cellulose and lignin components. Fourier transform infrared (FTIR) analysis was carried out to determine the functional groups. Proximate analysis showed the weight percentages of moisture contents, volatile matter, fixed carbon and ash contents as 7.25–9.27%, 61.79–73.28%, 16.50–27.92% and 2.13–3.72%, respectively. Ultimate analysis showed the ranges of carbon, hydrogen and oxygen as 44.27–49.41%, 5.3–6.10% and 41.93–49.44% respectively, while lower values of sulphur and nitrogen components were reported which are encouraging from an environmental perspective. Higher heating values (HHV) for the parts were reported to range between 17.85 and 20.93 MJ/kg on a dry basis.

Synthesis and Investigation of the Structural Properties of Al3+ Doped Mg Ferrites

The polycrystalline ferrites of MgAlxFe2-xO4 (0.0≤x≤0.4) were prepared by the conventional solid state ceramic method. The specimens were sintered at 13500C and X-ray diffraction experiments were done at room temperature which showed single phased cubic spinel structure. The lattice parameters were determined from the XRD data using Nelson-Riley extrapolation method and found to decrease with increasing Al concentration obeying Vegard’s law. The cation distribution and oxygen position parameters have also been determined by refining the data using the RIETAN-2000 in the Rietveld method which reveals that the samples possess cubic symmetry corresponding to the space group Fd-3m. The X-ray density and bulk density of each sample were calculated using the lattice parameters. The porosity has been determined from X-ray density (ρx) and bulk density (ρB) and it changes monotonically with Al content.

Robust doped BaCeO3-δ electrolyte for IT-SOFCs

Single phase polycrystalline BaZr0.3Ce0.5Y0.1Yb0.1O3 - δ electrolyte material was prepared by solid state reaction route. Rietveld analysis of the XRD data confirms the tetragonal symmetry in the I4/mcm space group with unit cell parameters of axa0=xa0bxa0=xa06.0567(3) Å and cxa0=xa08.5831(5) Å. The addition of ZnO as a sintering additive was found to reduce the sintering temperature and enhance both overall sinterability and grain growth. Sintering temperature was reduced by 200–300xa0°C, and a very high relative density of about 98% was achieved at 1400xa0°C. Impedance spectroscopy in humidified 5% H2/Ar atmosphere shows that the protonic conductivity at 600xa0°C was 8.60xa0×xa010−3xa0Sxa0cm−1. Thermal analysis performed in pure CO2 atmosphere shows very good chemical stability up to 1200xa0°C. Good biaxial flexure strength of 100–200xa0MPa was reported which makes this material a promising electrolyte material for intermediate temperature solid oxide fuel cells (IT-SOFCs).