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In this paper, a method of tuning a proportional-integral-derivative controller for a four degree-of-freedom lower limb exoskeleton using hybrid of genetic algorithm and particle swarm optimization is presented. Transfer function of each link of the lower limb exoskeleton acquired from a pendulum model, was used in a closed-loop proportional-integral-derivative control system, while each link was assumed as one degree-of-freedom linkage. In the control system, the hybrid algorithm was applied to acquire the parameters of the controller for each joint for minimizing the error. The algorithm started with genetic algorithm and continued via particle swarm optimization. Furthermore, a 3-dimensional model of the lower limb exoskeleton was simulated to validate the proposed controller. The trajectory of the control system with optimized proportional-integral-derivative controller via hybrid precisely follows the input signal of the desired. The result of the hybrid optimized controller was compared with genetic algorithm and particle swarm optimization based on statistics. The average error of the proposed algorithm showed the optimized results in comparison with genetic algorithm and particle swarm optimization. Furthermore, the advantages of the hybrid algorithm have been indicated by numerical analysis.

We previously reported that hydroxylated oxime ether lipids (OELs) efficiently deliver functional Dicer substrate siRNAs (DsiRNAs) in cells. Here, we explored in vivo utility of these OELs, using OEL4 as a prototype and report that surface modification of the OEL4 formulations was essential for their in vivo applications. These surface-modified OEL4 formulations were developed by inclusion of various PEGylated lipids. The vesicle stability and gene knock-down were dependent on the PEG chain length. OEL4 containing DSPE-PEG350 and DSPE-PEG1000 (surprisingly not DSPE2000) promoted gene silencing in cells. In vivo studies demonstrated that OEL4 vesicles formulated using 3 mol% DSPE-PEG350 accumulate in human lung cancer (A549-luc2) xenografts in mice and exhibit a significant increase in tumor to liver ratios. These vesicles also showed a statistically significant reduction of luciferase signal in tumors compared to untreated mice. Taken together, the scalable OEL4:DSPE-PEG350 formulation serves as a novel candidate for delivery of RNAi therapeutics.

Large middle cerebral artery (MCA) strokes remain a major cause for mortality and morbidity all over the world, and therefore early identification of patients with the highest risk for malignant cerebral edema is crucial for early intervention. Neutrophils to lymphocytes ratio (NLR) and peripheral total white blood cell (WBC) count are inflammatory markers done routinely for all patients, and this study evaluated the use of NLR and elevated white blood cell count within the first 24 h of MCA ischemic stroke onset, with the absence of significant hemorrhagic transformation, to predict malignant cerebral edema.A total of 156 patients with large MCA strokes were included. We collected demographic, clinical, radiological data, and NLR and WBCs within the first 24 h from admission.We excluded patients who had any underlying infections diagnosed 7 days before or within 72 h after admission. We used a body temp of 38 C or more, abnormal CXR or abnormal urine analysis within the first 72 h to exclude patients with possible infections.We excluded immune-compromised patients and patients on steroid therapy. We compared the NLR and WBC count in patients who developed malignant cerebral edema versus the patients who did not. NLR3.5 and3.5 was used for comparison. We then conducted multivariate logistic regression models to explore the relationship between cerebral edema, WBCs and NLR count simultaneously.NLR, WBC, radiological involvement of more than 50% of MCA territory infarction on presentation, hyperdense MCA sign, and NIH stroke scale were all significantly higher in patients with malignant cerebral edema within the first 24 h. Using univariate logistic regression, NLR performs better than WBC when predicting the occurrence of malignant cerebral edema (AUC = 0.74 vs. 0.62). However, NIH stroke scale scores, and radiological involvement of more than 50% of MCA territory infarction on the first 24 h of presentation on CT scan both showed better discriminative performance for malignant cerebral edema than NLR (AUC = 0.84 and 0.76, respectively). When combined, NLR3.5 paired with the NIH stroke scale score had the best predictive performance (AUC = 0.87).NLR3.5 can be used for early prognostication in patients with large vessel MCA ischemic strokes with no significant hemorrhagic transformation within the first 24 h regardless if they had reperfusion therapy or not. Combining NLR of3.5 in addition to high NIHSS provided the best predictive model in our study. Further studies are needed to further develop the best predictive model in diverse populations.

Helicobacter pylori (H. pylori) is a Gram-negative bacteria that colonizes the gastrointestinal mucosa and causes chronic inflammation.There are several studies related to cytokines concentrations in H. pylori infection, but there is no study that clarifies the role of IL-4 and IL-6 together in H. pylori infection.and methods: A total of (65) individuals, (25) healthy controls and (40) patients with H. pylori infection which are submitted to the hepato-gastrointestinal unit of AL-Imamian Al-Kadhimiyain medical hospital city in Baghdad consulted and diagnosed by traditional ways. In addition, the diagnosis was confirmed by ELISA Helicobacter pylori IgG kit. IL-4 and IL-6 levels were also assessed by using ELISA kits, according to the manufactures procedures.Significant increase of IL-4 and IL-6 concentration in seropositive patients compared with seronegative controls.Our findings and previous researches indicate that the immune response of gastric mucosa to H. pylori varies among patients. It depends on the stage of infection, and increases the cytokines secretion in the chronic stage, which is expected because of increased immune cell infiltration at the site of infection.

Two new bis(perfluoroalkyl)arylsulfonyl imide monomers, which contain the aryl diazonium moiety and intramolecular zwitterionic fragment, have been designed and prepared for the first time from perfluoro(3-oxa-4-pentene)sulfonyl fluoride. As promising monomer candidates for high-performance proton exchange membrane fuel cell electrolytes, these two monomers have furnished perfluorinated electrolytes that include the polymers from perfluorinated sulfonic acid or perfluorinated sulfonimide monomers. The synthesis strategies and NMR analysis are summarized and discussed in details.

A facile and efficient base-mediated protocol for debromination of vic-dibromides in perfluoroalkyl(aryl) compounds in aqueous medium has been demonstrated. With mild reaction conditions, the developed strategy has a good substrate scope and electron-deficient olefin products were obtained in good yields. A mechanistic explanation of the debromination is offered with three key experimental observations: (1) the reactions are accelerated by the more electron-rich nucleophiles, (2) the reactions are promoted by the more electron poor vic-dibromides in perfluoroalkyl compounds, and (3) the nucleophilic side reaction is preventable. It is evident that the electronic factors strongly dictate vic-dibromides elimination to the perfluorovinyl ethers, which are the precursors for various perfluorinated polymers. The different reaction conditions were tested in implicit solvent (water) conditions, which helped to confirm the E2-like mechanism.

Background Corona Virus Disease 2019 (COVID-19) cases continue to increase around the World. Typical symptoms include fever and respiratory illness but a constellation of multisystem involvement including central nervous system (CNS) and peripheral nervous system (PNS) have been reported with COVID-19. Acute ischemic strokes (AIS) have also been reported as a complication. Methodology We analyzed patient characteristics, clinical outcomes, laboratory results and imaging results of four patients with COVID-19 who had AIS. Results All four patients were =< 60 years, had hypoxemic respiratory failure secondary to pneumonia, elevated D-dimer and inflammatory markers. Conclusion Ischemic strokes are known complications in patients with severe COVID-19., Highlights • There is an association between acute ischemic stroke and COVID-19 infection. • COVID-19 related strokes can be multifocal. • Hypercoagulability and vasculitis due to intracranial cytokine storm are among the proposed mechanisms for AIS in COVID-19.

Achieving precise parameters of multi-joints actuators for Hip–Knee Exoskeleton (HKE) is a crucial process due to its non-linear characteristics. In this paper, a Genetic Algorithm (GA) based optimization is used for parameter estimation of the mathematical model for a four-Degree of Freedom (DoF) multi-joint HKE, which is a type of Lower Limb Exoskeleton (LLE). Mathematical model for electro-mechanical, mechanical, and electrical components of the HKE has been formulated, and its parameters are estimated using GA and experimental method. An objective function is determined based on the difference between the simulated and actual angular trajectory for each joint. The performance of the mathematical model is examined with different voltages under the range of 4 V to 8 V for hip and knee, respectively. Furthermore, the performance of the estimated model is compared with Particle Swarm Optimization (PSO). The results and numerical analysis demonstrated that the estimated model by GA and PSO with varying voltages predicted the actual angular trajectory with acceptable error, while GA provides the more accurate model. It can be ascertained that the proposed method of estimation for mathematical model of the HKE is applicable to identify its parameters, and useful for designing a control system.

Students Feedback Online (SuFO) is an online system that is used to evaluate the overall teaching and learning components in terms of lecturer's quality assurance and performance, content and infrastructure. In view of the importance of SuFO, a reliable instrument is deemed necessary for the evaluation of students’ perception of a lecturer's quality assurance and performance, content and infastructure in higher education in Malaysia. The objective of this study is to investigate the perception of students towards SuFO survey. This study was conducted at one of the campus of a public university in the centre region of Sarawak, Malaysia using a survey to investigate the perception of students towards SuFO survey. A total of 158 full time diploma students completed a questionnaire about views on the perceptions of students towards SuFO survey. The questionnaire had high internal consistency whereby the alpha value reported to be 0.863 for 30 items. Analysis of the students’ perception by gender (on independent samples t-test) showed that there is a significant difference in mean perception rating between male and female students (p

A technique for the modeling of nonlinear control processes using fuzzy modeling approach based on the Takagi–Sugeno fuzzy model with a combination of genetic algorithm and recursive least square is proposed. This paper discusses the identification of the parameters at the antecedent and consequent parts of the fuzzy model. For the antecedent fuzzy parameters, genetic algorithm is used to tune them while at the consequent part, recursive least squares approach is used to identify the system parameters. This approach is applied to a process control rig with three subsystems: a heating element, a heat exchanger and a compartment tank. Experimental results show that the proposed approach provides better modeling when compared with Takagi Sugeno fuzzy modeling technique and the linear modeling approach.