Biosynthesized Silver Nanoparticle (AgNP) From Pandanus odorifer Leaf Extract Exhibits Anti-metastasis and Anti-biofilm Potentials

Cancer and the associated secondary bacterial infections are leading cause of mortality, due to the paucity of effective drugs. Here, we have synthesized silver nanoparticles (AgNPs) from organic resource and confirmed their anti-cancer and anti-microbial potentials. Microwave irradiation method was employed to synthesize AgNPs using Pandanus odorifer leaf extract. Anti-cancer potential of AgNPs was evaluated by scratch assay on the monolayer of rat basophilic leukemia (RBL) cells, indicating that the synthesized AgNPs inhibit the migration of RBL cells. The synthesized AgNPs showed MIC value of 4–16 µg/mL against both Gram +ve and Gram -ve bacterial strains, exhibiting the anti-microbial potential. Biofilm inhibition was recorded at sub- MIC values against Gram +ve and Gram -ve bacterial strains. Violacein and alginate productions were reduced by 89.6 and 75.6%, respectively at 4 and 8 µg/mL of AgNPs, suggesting anti-quorum sensing activity. Exopolysaccharide production was decreased by 61–79 and 84% for Gram +ve and Gram -ve pathogens respectively. Flagellar driven swarming mobility was also reduced significantly. Furthermore, In vivo study confirmed their tolerability in mice, indicating their clinical perspective. Collective, we claim that the synthesized AgNPs have anti-metastasis as well as anti-microbial activities. Hence, this can be further tested for therapeutic options to treat cancer and secondary bacterial infections

Biosynthesized Silver Nanoparticle (AgNP) From Pandanus odorifer Leaf Extract Exhibits Anti-metastasis and Anti-biofilm Potentials

Cancer and the associated secondary bacterial infections are leading cause of mortality, due to the paucity of effective drugs. Here, we have synthesized silver nanoparticles (AgNPs) from organic resource and confirmed their anti-cancer and anti-microbial potentials. Microwave irradiation method was employed to synthesize AgNPs using Pandanus odorifer leaf extract. Anti-cancer potential of AgNPs was evaluated by scratch assay on the monolayer of rat basophilic leukemia (RBL) cells, indicating that the synthesized AgNPs inhibit the migration of RBL cells. The synthesized AgNPs showed MIC value of 4–16 µg/mL against both Gram +ve and Gram -ve bacterial strains, exhibiting the anti-microbial potential. Biofilm inhibition was recorded at sub- MIC values against Gram +ve and Gram -ve bacterial strains. Violacein and alginate productions were reduced by 89.6 and 75.6%, respectively at 4 and 8 µg/mL of AgNPs, suggesting anti-quorum sensing activity. Exopolysaccharide production was decreased by 61–79 and 84% for Gram +ve and Gram -ve pathogens respectively. Flagellar driven swarming mobility was also reduced significantly. Furthermore, In vivo study confirmed their tolerability in mice, indicating their clinical perspective. Collective, we claim that the synthesized AgNPs have anti-metastasis as well as anti-microbial activities. Hence, this can be further tested for therapeutic options to treat cancer and secondary bacterial infections

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Novel Level-Shifted PWM Technique for Equal Power Sharing among Quasi-Z-Source Modules in Cascaded Multilevel Inverter

Phase-shifted pulsewidth modulation (PS-PWM) is a well-known switching technique for quasi-Z-source (qZS)-based cascaded multilevel inverters (qZS-CMI). PS-PWM ensures equal power distribution (among operating modules) and equal switchings in all the semiconductors of the every given module; however, this technique suffers from higher number of switchings. On the other hand, level-shifted pulsewidth modulation (LS-PWM) ensures optimal switching but suffers from uneven distribution of power among the all the operating modules and also all the semiconductors of the same module of qZSI. This article proposes a novel switching technique which combines the advantages of both PS-PWM and LS-PWM, such as equal power distribution (among operating modules) and optimal switching sequence along with equal switch utilization. The proposed method is phase opposed disposed PS-PWM. This article details the switching technique along with switching loss analysis and compares it with the PS-PWM technique to show its superiority. Simulation results are carried out to study the cascaded multilevel inverter (CMLI) performance. Experimental prototype is developed to validate the performance of the proposed modulation.10.13039/100008982-Qatar National Research Fund (Grant Number: NPRP X-033-2-007)Scopu

Experimental Investigation and Comparative Evaluation of Standard Level Shifted Multi-Carrier Modulation Schemes with a Constraint GA Based SHE Techniques for a Seven-Level PUC Inverter

This paper investigates a reduced switch count topology for seven-level single-phase voltage-source inverter, nomenclatures as asymmetrical holding capacitor or also known as asymmetrical flying level capacitor or packed U-cell (PUC). Modular configuration of the inverter consists of one U-cell, four additional power switches, and one dc link. U-cell network is an arrangement of two semiconductor switches with one holding or clamping capacitor. Topology offers a reduced switch count solution with simple control strategy compared to the existing seven-level inverters. Different standard multicarrier sinusoidal pulse-width modulation techniques (SPWMs) are adapted for the generation of switching gate signals for the PUC power switches, and these SPWMs are compared with novel optimization-based selective harmonic elimination (SHE) that employs genetic algorithm (GA) for solving nonlinear SHE equation with a constraint that eliminated all third-order harmonics efficiently. The investigation that involves analysis and comparison is done for obtaining reduced total harmonic distortion (THD) by using different level-shifted multicarrier SPWM schemes along with proposed GA-based SHE. Obtained findings with design of dc voltage and load current controllers are elaborated and presented in this paper. For better understanding, the converter topology is tested under different dynamic conditions. Mathematical background developed on the theoretical basis is verified by numerical simulation software and also validated on the developed laboratory-scale prototype experimental setup.This work was supported in part by the Qatar University under High Impact Grant QUHI-CENG-19/20-2, and in part by the Qatar National Library, Doha, Qatar.Scopu

A hybrid active and reactive power control with Quasi Z-source inverter in single-phase grid-connected PV systems

This paper presents a hybrid method of active power and reactive power control strategy with Quasi Z-source inverter (QZSI) in single phase grid connected photovoltaic (PV) systems. The maximum power from the PV panel is extracted and most of it is supplied as active power to the grid. The major portion of required reactive power exchange to the grid is done by means of thyristor switched capacitor (TSC) and thyristor switched reactor (TSR) to improve the generation capacity of the PV system. In the proposed topology inverter shares the minimum reactive power and large change in reactive power will be delivered/absorbed by the TSC-TSR to get smoother operation in reactive power control. The DC voltage controller and the AC current controller is discussed in brief. The mathematical analysis for grid synchronization method is presented in detail. The control algorithm for active power and reactive power is analyzed and discussed in the paper. The simulation results are shown for validating the proposed concept.This publication was made possible by NPRP-EP grant # [X-033-2-007] from the Qatar National Research Fund (a member of Qatar Foundation).Scopu

Switched Inductor Quazi Switched boost Converter for Nano - Grid Applications

Each commercial and residential buildings energy management system can be efficiently/ economically realized by integration of the solar photovoltaics (acting as the renewable power generator), battery energy storage system (ESS) along with the power electronic converters. The switched boost converters are the attractive solutions for the nano-grid applications where with a single stage operation, voltage boost, storage in battery and simultaneously inversion to the required AC voltage levels can be achieved. Here, a novel switched inductor Quasi switched boost converter is proposed. The proposed converter can operate in different modes such as multiple inputs and multiple outputs for the battery storage, PV and the load. The proposed converter reduces the shoot through requirement and improves the modulation index by increasing the gain of the DC-DC stage. The benefits of the proposed converter are: 1) high gain during PV to BESS mode, 2) high modulation index for the DC-AC stage, 3) continuous input current, 4) reduced shoot-through time which reduces the current ripple, 5) high efficiency and 6) increased reliability. The different operating modes to achieve these benefits are also presented in this paper. The detailed mathematical modelling of the proposed converter is carried out. MATLAB/SIMULINK simulation results which validates the benefits with proposed converter are given. Experimental results are obtained by developing a 120W prototype in the laboratory.ACKNOWLEDGMENT This publication was made possible by QUCG grant # [CENG-19/20-5] from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.Scopu