10 research outputs found

    Flexible CO<sub>2</sub> sensor architecture with selective nitrogen functionalities by one-step laser-induced conversion of versatile organic ink

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    Nitrogen-doped carbons (NC) are a class of sustainable materials for selective CO2 adsorption. We introduce a versatile concept to fabricate flexible NC-based sensor architectures for room-temperature sensing of CO2 in a one-step laser conversion of primary coatings cast from abundant precursors. By the unidirectional energy impact in conjunction with depth-dependent attenuation of the laser beam, a layered sensor heterostructure with porous transducer and active sensor layer is formed. Comprehensive microscopic and spectroscopic cross-sectional analyses confirm the preservation of a high content of imidazolic nitrogen in the sensor. The performance was optimized in terms of material morphology, chemical composition, and surface chemistry to achieve a linear relative resistive response of up to ∆R/R0 = -14.3% (10% of CO2). Thermodynamic analysis yields ΔadsH values of -35.6 kJ·mol-1 and 34.1 kJ·mol-1 for H2O and CO2, respectively. The sensor is operable even in humid environments (e.g., ∆R/R0,RH=80% = 0.53%) and shows good performance upon strong mechanical deformation

    Adherence to Artemisinin-based Combination Therapy for the Treatment of Malaria: A Systematic Review of the Evidence.

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    Increasing access to and targeting of artemisinin-based combination therapy (ACT) is a key component of malaria control programmes. To maximize efficacy of ACT and ensure adequate treatment outcomes, patient and caregiver adherence to treatment guidelines is essential. This review summarizes the current evidence base on ACT adherence, including definitions, measurement methods, and associated factors. A systematic search of the published literature was undertaken in November 2012 and updated in April 2013. Bibliographies of manuscripts were also searched and additional references identified. Studies were included if they involved at least one form of ACT and reported an adherence measurement. The search yielded 1,412 records, 37 of which were found to measure adherence to ACT. Methods to measure adherence focused on self-report, pill counts and bioassays with varying definitions for adherence. Most studies only reported whether medication regimens were completed, but did not assess how the treatment was taken by the patient (i.e. timing, frequency and dose). Adherence data were available for four different ACT formulations: artemether-lumefantrine (AL) (range 39-100%), amodiaquine plus artesunate (AQ + AS) (range 48-94%), artesunate plus sulphadoxine-pyrimethamine (AS + SP) (range 39-75%) and artesunate plus mefloquine (AS + MQ) (range 77-95%). Association between demographic factors, such as age, gender, education and socio-economic status and adherence to ACT regimens was not consistent. Some evidence of positive association between adherence and patient age, caregiver education levels, drug preferences, health worker instructions, patient/caregiver knowledge and drug packaging were also observed. This review highlights the weak evidence base on ACT adherence. Results suggest that ACT adherence levels varied substantially between study populations, but comparison between studies was challenging due to differences in study design, definitions, and methods used to measure adherence. Standardising methodologies for both self-report and bioassays used for evaluating adherence of different formulations across diverse contexts would improve the evidence base on ACT adherence and effectiveness; namely, specific and measurable definitions for adherence are needed for both methodologies. Additionally, further studies of the individual factors and barriers associated with non-adherence to ACT are needed in order to make informed policy choices and to improve the delivery of effective malaria treatment

    Flexible CO2 Sensor Architecture with Selective Nitrogen Functionalities by One Step Laser Induced Conversion of Versatile Organic Ink

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    Nitrogen containing carbons NC are a class of sustainable materials for selective CO2 adsorption. A versatile concept is introduced to fabricate flexible NC based sensor architectures for room temperature sensing of CO2 in a one step laser conversion of primary films cast from abundant precursors. By the unidirectional energy impact in conjunction with depth dependent attenuation of the laser beam, a layered sensor heterostructure with a porous transducer and active sensor layer is formed. Comprehensive microscopic and spectroscopic cross sectional analyses confirm the preservation of the high content of imidazolic nitrogen in the sensor. The performance is optimized in terms of material morphology, chemical composition, and surface chemistry to achieve a linear relative resistive response of up to amp; 916;R R0 amp; 8722;14.3 10 of CO2 . Thermodynamic analysis yields amp; 916;adsH values of amp; 8722;35.6 and 34.1 kJ mol amp; 8722;1 for H2O and CO2, respectively. The sensor is operable even in humid environments e.g., amp; 916;R R0,RH 80 0.53 and shows good performance upon strong mechanical deformatio
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