Worldwide tuberculosis (TB) takes more lives than any other infectious diseases. WHO estimates around 68,000 incident TB cases in Nepal. However, in 2018 only around 27,232 new TB cases were reported ...in the national system, resulting around 40,768 incident TB cases missing every year in Nepal. National Tuberculosis Control Center carried out this study in anti-retroviral therapy (ART) sites to estimate the prevalence of TB and identify the associated risk factors for TB among the people living with Human Immunodeficiency Virus (PLHIVs) in Nepal.
It was a cross-sectional institution-based study conducted between March and August 2018. Six ART sites with high caseloads of PLHIVs were selected. PLHIVs who were equal or above 18 years of age and were in ART program at the selected study sites were considered eligible for the study. Diagnosis of tuberculosis among PLHIVs who agreed to participate in the study was carried out as per the National Tuberculosis Management Guideline of National Tuberculosis Program of Nepal.
Among 403 PLHIVs, tuberculosis was diagnosed in 40 (9.9%) individuals. Median age of the participants was 36 (30-43) years. Prevalence of TB was significantly higher among male PLHIVs than female PLHIVs (13.6% Vs 5.8%; P = 0.02) and Dalit ethnic group compared to Brahmin/Chettri (22.0%Vs5.9%, P = 0.01). The risk of developing TB was found significant among those with HIV stage progressed to WHO stage 3 and 4 (OR = 4.85, P<0.001) and with the family history of TB (OR = 4.50, P = 0.002).
Prevalence of TB among PLHIVs in Nepal was found 9.9%. Risk of developing TB was higher among PLHIVs who were male, Dalit, with HIV stage progressed to WHO stage 3 and 4 and with family history of TB. Hence, targeted interventions are needed to prevent the risk of developing TB among PLHIVs. Similarly, integrated, and comprehensive TB and HIV diagnosis and treatment services are needed for the management of TB/HIV co-infection in Nepal.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A novel flux-intensifying interior (FII) permanent magnet synchronous motor (PMSM) based on multilayer barriers in rotor structure with improved torque performance for solar water pump system is ...proposed here. The conventional interior (CI) PMSM generates maximum total torque on application of negative current along d-axis, resulting in an increment of demagnetization possibility of permanent magnets (PMs). Although flux-intensifying PMSMs solve this issue, their reluctance torque is lower due to the reduced saliency difference. This problem is solved by the presented FII-PMSM, which produces higher reluctance torque through specially designed barriers. Two types of barriers namely, inner and outer cutoff barriers are designed in rotor along quadrature axis. The inner barriers realize flux-intensifying effect while the outer cutoff barriers increase the saliency difference and hence the reluctance torque. Besides, the dimensions of barriers are optimized by using parametric optimization to maximize saliency difference and minimize torque ripples. The finite element methods based electromagnetic performances of FII-PMSM like inductance curves, torque profiles, airgap gap flux density, back electromotive force plots, efficiency map, output power map and PM flux density are obtained and compared with the CI-PMSM to show the superiority of presented motor.
•AC-DC Power Conversion.•Low Power-Input Ceiling Fan.•Power Factor Correction.•Commutation Control of Voltage Source Inverter.•Low Supply-Current Total Harmonics Distortion (THD).
This paper presents ...a permanent magnet brushless direct current motor (PMBLDCM) ceiling-fan (CF) that operates on AC mains with a unity power factor (UPF). An AC-DC power-factor-corrected converter (PFCC) performs in discontinuous-conduction mode (DCM) to facilitate various merits such as an inherent UPF, reduced passive components size, stable operation, and required voltage control. The PMBLDCM ceiling fan speed is controlled by a smooth change in converter voltage output, and it helps to operate a voltage source inverter (VSI) at a fundamental frequency with low switching losses. This control maximizes efficiency of a ceiling fan. The THD (Total Harmonics Distortion) of a supply-current is reduced with a wide range of speed control and supply voltage fluctuations. A prototype of it is developed to validate the design and control. Its performance is compared with a conventional PMBLDCM ceiling fan. Test results are shown to verify the design of PFCC. The power quality indices (PQI) at input supply are meeting the IEC61000-3-2 standard.
This study includes the utilization of sweet lemon peel (SLP) and sugarcane bagasse (SB) in solid‐state fermentation using Kluyveromyces marxianus for bioflavor compounds production adopting response ...surface methodology. The major flavor compounds, 2‐phenylethanol (2‐PE) and 2‐phenylethyl acetate (2‐PEA) were quantified using gas chromatography–mass spectrometry with and without adding any supplements. Quantification of flavor compounds indicated that without adding any accessory in the substrate, the concentration of 2‐PE using SLP and SB was 0.15 ± 0.003 mg/g and 0.14 ± 0.002 mg/g, respectively. Whereas 2‐PEA concentration using SLP and SB was observed as 0.01 ± 0.008 mg/g and 0.02 ± 0.001 mg/g, respectively. The addition of l‐phenylalanine (l‐phe) in the substrates showed 30%–75% enhancement in the production of 2‐PE and 2‐PEA. The present study indicates that the K. marxianus is a potential microbial cell factory for the production of 2‐PE and 2‐PEA with the addition of synthetic l‐phe having a plethora of applications in food and pharmaceutical industries.
This study deals with the analysis and implementation of an HPF (high power factor) single-stage, single switch buck converter-based power supply design for an LED (light emitting diode) lamp load of ...13 W operated at the universal ac mains. In general purpose lighting applications, a buck converter is a good candidate for power factor correction with low component count and reduced cost. In low-power lighting, it is a tough task to control the THDi (total harmonic distortion) of ac mains current under the limits of strict international standards such as IEC-61000-3-2 with universal ac mains for class D equipments. In the proposed optocouplerless topology, HPF operation at input ac mains is achieved by operating the buck ac–dc converter in continuous conduction mode. The design, modelling and simulation of the proposed topology are executed using MATLAB-Simulink and sim-power system toolboxes. A prototype of the power supply for LED lamp is developed for multiple LEDs connected in series configuration. The efficiency of the proposed LED lamp driver is observed as 83.76% at rated voltage of 220 V and the THD of ac mains current less than 17.27% for a wide range of voltages of 90–270 V.
► Cellulose acetate Zr (IV) phosphate nanocomposite was synthesized. ► The ion exchange capacity of CA/ZPNC was explored. ► CA/ZPNC was highly selective for lead ions. ► CA/ZPNC proved to be an ...efficient photocatalyst for dye degradation.
Cellulose acetate–zirconium (IV) phosphate nanocomposite (CA/ZPNC) was synthesized by sol–gel technique at pH 0–1 and was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, Fourier infrared spectroscopy (FTIR) and thermal analysis (TGA/DTA/DSC). Ion exchange capacity, pH titration, elution concentration, elution behaviour, thermal stability and distribution coefficient were investigated to explore ion exchange behaviour of CA/ZPNC. The nanocomposite showed an ion-exchange capacity of 1.4mequiv.g−1 for Na+ and was highly selective for Pb2+ and Zn2+ over many other metal ions. The photocatalytic activity of the CA/ZPNC was explored for degradation of a model Congo red dye from aqueous phase. 90% of dye was removed in 60min of irradiation. Simultaneous adsorption and photocatalysis had synergetic effect on dye degradation.
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•Styrene–tin (IV) phosphate nanocomposite (ST/TPNC) ion exchanger was chemically prepared by simple sol–gel method at pH 0–1.•ST/TPNC exhibited higher ion exchange capacity as ...compared to its inorganic component.•ST/TPNC retained about 35.5% of the initial value of ion exchange capacity after heating up to 400°C.•ST/TPNC was used as efficient photocatalyst for the degradation of MB dye from aqueous system in the presence of solar light.•The pH titrations studies confirmed the monofunctional strong cationic nature of ST/TPNC.
Styrene–tin (IV) phosphate nanocomposite (ST/TPNC) ion exchanger was used as efficient photocatalyst for the degradation of methylene blue dye from aqueous system in the presence of solar light. ST/TPNC exhibited a high efficiency in heterogeneous photocatalytic process for the removal of MB from the water system. The degradation efficiency after 2h illumination was 80%. The degradation of MB follows the pseudo-first-order kinetics with rate constant 0.00702min−1. The nanocomposite ion exchanger was explored for its ion exchange capacity, pH titration, elution behavior, elution concentration and distribution coefficient (Kd). ST/TPNC exhibited a higher ion exchange capacity (1.83meg/g) compared to its inorganic counterpart (0.55meg/g). ST/TPNC was characterized using some techniques such as Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and thermogravimetric analysis (TGA).
This paper deals with the design and performance analysis of a three-phase single stage solar photovoltaic integrated unified power quality conditioner (PV-UPQC). The PV-UPQC consists of a shunt and ...series-connected voltage compensators connected back-to-back with common dc-link. The shunt compensator performs the dual function of extracting power from PV array apart from compensating for load current harmonics. An improved synchronous reference frame control based on moving average filter is used for extraction of load active current component for improved performance of the PV-UPQC. The series compensator compensates for the grid side power quality problems such as grid voltage sags/swells. The compensator injects voltage in-phase/out of phase with point of common coupling (PCC) voltage during sag and swell conditions, respectively. The proposed system combines both the benefits of clean energy generation along with improving power quality. The steady state and dynamic performance of the system are evaluated by simulating in MATLAB-Simulink under a nonlinear load. The system performance is then verified using a scaled down laboratory prototype under a number of disturbances such as load unbalancing, PCC voltage sags/swells, and irradiation variation.
This article deals with the multimode operation of a photovoltaic (PV) array, a battery, the grid and the diesel generator (DG) set-based charging station (CS) for providing the continuous charging ...and uninterruptible supply to the household loads. In this CS, a single voltage source converter operates the CS in an islanded mode, the grid connected mode and the DG set connected mode (DGM) and performs various tasks, such as power management among different energy sources and charging the electric vehicles (EVs), extraction of maximum power from the PV array, the regulation of voltage and frequency of the generator, harmonics current compensation of nonlinear loads and intentional reactive power compensation. The control of charging station (CS) is designed such that it primarily takes power from the PV array and a storage battery. In the absence of these two sources, the charging station takes power from the grid, and at last, it utilizes a squirrel cage induction generator-based DG set. However, the DG set is operated such that it generates up to 33% more power than its rated capacity without exceeding the rated current in windings, therefore, the size of the DG is reduced. Moreover, the voltage and frequency of the generator are regulated at its rated values without a mechanical speed governor. In all operating modes, the CS complies with the IEEE 1547 standard and the total harmonic distortion of voltage and current, is achieved less than 5%.
This paper presents an implementation of sliding mode controller (SMC) along with a proportional and integral (PI) controller for a DSTATCOM (Distribution STATic COMpensator) for improving current ...induced power quality issues and voltage regulation of three-phase self-excited induction generator (SEIG). The use of SMC for regulating the DC link voltage of DSTATCOM offers various advantages such as reduction in number of sensors for estimating reference currents and the stable DC link voltage during transient conditions. The use of PI controller for terminal voltage control gives the error free voltage regulation in steady state conditions. The voltage regulation feature of DSTATCOM offers the advantages of single point voltage operation at the generator terminals with the reactive power compensation which avoids the saturation in the generator. Other offered advantages are balanced generator currents under any loading condition, harmonic currents mitigation, stable DC link voltage and the reduced number of sensors. The SMC algorithm is successfully implemented on a DSTATCOM employed with a three-phase SEIG feeding single phase or three phase loads. The performance of the proposed control algorithm is found satisfactory for voltage regulation and mitigation of power quality problems like reactive power compensation, harmonics elimination, and load balancing under nonlinear/linear loads.
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