Malaria elimination campaigns in the Lake Kariba region of Zambia: a spatial dynamical model

Background As more regions approach malaria elimination, understanding how different interventions interact to reduce transmission becomes critical. The Lake Kariba area of Southern Province, Zambia, is part of a multi-country elimination effort and presents a particular challenge as it is an interconnected region of variable transmission intensities. Methods In 2012-13, six rounds of mass-screen-and-treat drug campaigns were carried out in the Lake Kariba region. A spatial dynamical model of malaria transmission in the Lake Kariba area, with transmission and climate modeled at the village scale, was calibrated to the 2012-13 prevalence survey data, with case management rates, insecticide-treated net usage, and drug campaign coverage informed by surveillance. The model was used to simulate the effect of various interventions implemented in 2014-22 on reducing regional transmission, achieving elimination by 2022, and maintaining elimination through 2028. Findings The model captured the spatio-temporal trends of decline and rebound in malaria prevalence in 2012-13 at the village scale. Simulations predicted that elimination required repeated mass drug administrations coupled with simultaneous increase in net usage. Drug campaigns targeted only at high-burden areas were as successful as campaigns covering the entire region. Interpretation Elimination in the Lake Kariba region is possible through coordinating mass drug campaigns with high-coverage vector control. Targeting regional hotspots is a viable alternative to global campaigns when human migration within an interconnected area is responsible for maintaining transmission in low-burden areas

Flexible transbronchial optical frequency domain imaging smart needle for biopsy guidance

Transbronchial needle aspiration (TBNA) is a procedure routinely performed to diagnose peripheral pulmonary lesions. However, TBNA is associated with a low diagnostic yield due to inappropriate needle placement. We have developed a flexible transbronchial optical frequency domain imaging (TB-OFDI) catheter that functions as a “smart needle” to confirm the needle placement within the target lesion prior to biopsy. The TB-OFDI smart needle consists of a flexible and removable OFDI catheter (430 µm dia.) that operates within a standard 21-gauge TBNA needle. The OFDI imaging core is based on an angle polished ball lens design with a working distance of 160 µm from the catheter sheath and a spot size of 25 µm. To demonstrate the potential of the TB-OFDI smart needle for transbronchial imaging, an inflated excised swine lung was imaged through a standard bronchoscope. Cross-sectional and longitudinal OFDI results reveal the detailed network of alveoli in the lung parenchyma suggesting that the TB-OFDI smart needle may be a useful tool for guiding biopsy acquisition to increase the diagnostic yield

Global air conditioning performance indicator (ACPI) for buildings, in tropical climate

The selection of the most suitable HVAC technology for buildings, is a complex challenge. Many factors such as, the features of the building, climatic conditions, energy consumption, Indoor Air Quality (IAQ), thermal comfort, regulations, aspects, economic and environmental aspects, all of which are shown on a local and national scope. There is no standard methodology that guarantees a single criterion for the selection of HVAC systems. Therefore, in its solution, as in almost all decision-making problems in the field of engineering, two different aspects are considered, theoretical and practical (Moreno, 2002) [1], thus forming a typical multi-criteria decision problem. This study proposes an integral performance indicator for the selection of air conditioning systems (ACPI), based on the multicriteria method of the Analytic Hierarchy Process (AHP), in order to choose the best HVAC system variant, based on its classification by integrating energy, environmental, and economic criteria. For the definition of the criteria, studies on HVAC system selection were reviewed and classified, applying multi-criteria on methods. The criteria were weighted based on surveys issued by a team made up of Professors/Researchers, architects, engineers, installers and managers linked to the HVAC sector. The ACPI model obtained, shows that the highest weighting corresponds to building energy consumption index 26.6%, IAQ 20.6%, thermal comfort 18.6%, CO2 emissions 12.1%, and finally, investment costs, operation and maintenance costs 11.6% and 10.3% respectively. The proposed ACPI, together with its analysis methodology, will allow researchers, architects, engineers, and government administration, to consider a wide range of alternative HVAC systems applied in buildings. With this, it will be possible to select them based on a decision-making model with a reliable source of information

Energy evaluation and energy savings analysis with the 2 selection of AC systems in an educational building

This paper presents an energy performance assessment on an educational building in Barranquilla, Colombia. The electricity consumption performance was assessed using the software DesignBuilder for two different Air Conditioning (AC) systems. The current electricity intensity is 215.3 kWh/m2 -year and centralized AC systems with individual fan coils and a water chiller share 66% of the total consumption and lighting at 16%. The simulation of the AC technology change to Variable Refrigerant Flow (VRF) resulted in an improvement of 38% in AC energy intensity with 88 kWh/m2 -year and significant savings in electricity consumption and life-cycle cost of AC systems in buildings.Este artículo presenta una evaluación del desempeño energético en un edificio educativo en Barranquilla, Colombia. El rendimiento del consumo de electricidad se evaluó mediante el software DesignBuilder para dos sistemas de aire acondicionado (AC) diferentes. La intensidad actual de la electricidad es 215,3 kWh / m2-año y sistemas de aire acondicionado centralizados con fan coils individuales y un enfriador de agua compartido 66% del consumo total e iluminación al 16%. La simulación de la tecnología AC cambia a El flujo de refrigerante variable (VRF) resultó en una mejora del 38% en la intensidad de energía de CA con 88 kWh / m2 al año y ahorros significativos en el consumo de electricidad y el costo del ciclo de vida de los sistemas de CA en edificios

Experimental study and analysis of thermal comfort in a university campus building in tropical climate

This study presents the evaluation of the performance and acceptability of thermal comfort by students in the classrooms of a university building with minisplit-type air-conditioning systems, in a tropical climate. To carry out the study, temperature and humidity measurements were recorded, both outside and inside the selected classrooms, while the students were asked to complete thermal surveys on site. The survey model is based on the template proposed by Fanger and it was applied to a total number of 584 students. In each classroom, the Predicted Mean Vote (PMV) and the Predicted Percentage Dissatisfied (PPD) were estimated according to Fanger’s methodology, as well as the Thermal Sensation Vote (TSV) and the Actual Percentage Dissatisfied (APD), which were obtained from the measurements and the surveys. The results of this study showed that the PMV values, although they may vary with the insulation of the clothing, do not affect the TSV. Furthermore, comparing PMV vs. TSV scores, a 2 ◦C to 3 ◦C difference in operating temperature was found, whereby the thermal sensitivity for TSV was colder, so it could be assumed that the PMV model overestimates the thermal sensitivity of students in low-temperature conditions. In addition, an acceptability by 90% with thermal preferences between 23 ◦C and 24 ◦C were also found. These results indicate that it is possible to increase the temperature set point in minisplit-type air-conditioning system from 4 ◦C to 7 ◦C with respect to the currently set temperatures, without affecting the acceptability of the thermal environment to the students in the building

Tailoring tobacco hairy root metabolism for the production of stilbenes

Tobacco hairy root (HR) cultures, which have been widely used for the heterologous production of target compounds, have an innate capacity to bioconvert exogenous t-resveratrol (t-R) into t-piceatannol (t-Pn) and t-pterostilbene (t-Pt). We established genetically engineered HR carrying the gene encoding stilbene synthase (STS) from Vitis vinifera and/or the transcription factor (TF) AtMYB12 from Arabidopsis thaliana, in order to generate a holistic response in the phenylpropanoid pathway and coordinate the up-regulation of multiple metabolic steps. Additionally, an artificial microRNA for chalcone synthase (amiRNA CHS) was utilized to arrest the normal flux through the endogenous chalcone synthase (CHS) enzyme, which would otherwise compete for precursors with the STS enzyme imported for the flux deviation. The transgenic HR were able to biosynthesize the target stilbenes, achieving a production of 40 μg L-1 of t-R, which was partially metabolized into t-Pn and t-Pt (up to 2.2 μg L-1 and 86.4 μg L-1, respectively), as well as its glucoside piceid (up to 339.7 μg L-1). Major metabolic perturbations were caused by the TF AtMYB12, affecting both primary and secondary metabolism, which confirms the complexity of biotechnological systems based on seed plant in vitro cultures for the heterologous production of high-value molecules

Dissociation of Water on Defective Carbon Substrates

Article on the dissociation of water on defective carbon substrates

Tailoring tobacco hairy root metabolism for the production of stilbenes

Tobacco hairy root (HR) cultures, which have been widely used for the heterologous production of target compounds, have an innate capacity to bioconvert exogenous t-resveratrol (t-R) into t-piceatannol (t-Pn) and t-pterostilbene (t-Pt). We established genetically engineered HR carrying the gene encoding stilbene synthase (STS) from Vitis vinifera and/or the transcription factor (TF) AtMYB12 from Arabidopsis thaliana, in order to generate a holistic response in the phenylpropanoid pathway and coordinate the up-regulation of multiple metabolic steps. Additionally, an artificial microRNA for chalcone synthase (amiRNA CHS) was utilized to arrest the normal flux through the endogenous chalcone synthase (CHS) enzyme, which would otherwise compete for precursors with the STS enzyme imported for the flux deviation. The transgenic HR were able to biosynthesize the target stilbenes, achieving a production of 40 μg L−1 of t-R, which was partially metabolized into t-Pn and t-Pt (up to 2.2 μg L−1 and 86.4 μg L−1, respectively), as well as its glucoside piceid (up to 339.7 μg L−1). Major metabolic perturbations were caused by the TF AtMYB12, affecting both primary and secondary metabolism, which confirms the complexity of biotechnological systems based on seed plant in vitro cultures for the heterologous production of high-value molecules.This work has been supported by a grant from the Spanish Ministry of Science and Innovation (BIO2014-51861-R, BIO2017-82374-R), Generalitat de Catalunya (2014SGR215). Diego Hidalgo is a predoctoral fellow of Mexican CONACyT