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A Systematic Review and International Web-Based Survey of Randomized Controlled Trials in the Perioperative and Critical Care Setting: Interventions Reducing Mortality
No full textThe authors aimed to identify interventions documented by randomized controlled trials (RCTs) that reduce mortality in adult critically ill and perioperative patients, followed by a survey of clinicians’ opinions and routine practices to understand the clinicians’ response to such evidence. The authors performed a comprehensive literature review to identify all topics reported to reduce mortality in perioperative and critical care settings according to at least 2 RCTs or to a multicenter RCT or to a single-center RCT plus guidelines. The authors generated position statements that were voted on online by physicians worldwide for agreement, use, and willingness to include in international guidelines. From 262 RCT manuscripts reporting mortality differences in the perioperative and critically ill settings, the authors selected 27 drugs, techniques, and strategies (66 RCTs, most frequently published by the New England Journal of Medicine [13 papers], Lancet [7], and Journal of the American Medical Association [5]) with an agreement ≥67% from over 250 physicians (46 countries). Noninvasive ventilation was the intervention supported by the largest number of RCTs (n = 13). The concordance between agreement and use (a positive answer both to “do you agree” and “do you use”) showed differences between Western and other countries and between anesthesiologists and intensive care unit physicians. The authors identified 27 clinical interventions with randomized evidence of survival benefit and strong clinician support in support of their potential life-saving properties in perioperative and critically ill patients with noninvasive ventilation having the highest level of support. However, clinician views appear affected by specialty and geographical location. © 2018 Elsevier Inc
Dengue protease inhibition activity of selected malaysian medicinal herbs
No full textDengue fever is one of major health problem around the world including Malaysia. It is caused by the arthropode-borne flavivirus and transmitted by the bite of the Aedes aegypti or Aedes albopictus mosquito infected with one of the four dengue virus serotypes (DENV-1, DENV-2, DENV-3, or DENV-4). In this study, a screening exercise of various Malaysian medicinal plants showed that the extracts of Lawsonia inermis, Dryobalanops aromatica, Punica granatum, Zizyphus jujuba Lam. and Zingiber zerumbet exhibited potent inhibitory activity against NS2B-NS3 serine protease. The methanol extracts of Dryobalanops aromatica showed inhibition of 99.70 % at concentration of 200 µg/mL with IC50 value of 0.30 ± 0.16 µg/mL. © 2019, Malaysian Society for Parasitology. All rights reserved
Absolute Configuration of Alkaloids from Uncaria longiflora through Experimental and Computational Approaches
No full textThe structure elucidation of three new alkaloids named isoformosaninol (1), formosaninol (2), and longiflorine (3), isolated from the leaves of Uncaria longiflora var. pteropoda (Miq.) Ridsdale, along with their biosynthetic pathways are discussed. Their absolute structures were determined through a combination of physical data interpretation and quantum chemical calculations using the time-dependent density functional theory (TDDFT) method. Copyright © 2019 American Chemical Society and American Society of Pharmacognosy
Preparation and characterization of ZnO/ZnAl2O4-mixed metal oxides for dye-sensitized photodetector using Zn/Al-layered double hydroxide as precursor
No full textIn this article, a simple new technique has been developed for the preparation of ZnO/ZnAl2O4-mixed metal oxide (MMO) as anode materials for visible light dye-sensitized (DS) photodetector using Zn/Al-layered double hydroxide (LDH) as precursor. Subsequently, a detailed correlation between the structural properties of the prepared samples and the photo-responsive behavior of the fabricated DS photodetectors was elucidated. Specifically, it is evidenced that a high surface area of the prepared mesoporous MMO anode materials exhibit excellent dye absorptivity and thus facilitate free electron transfer and increase the photocurrent in the fabricated DS photodetector. A significant bathochromic shift was observed in the optical energy of the prepared MMO samples under the increment of molar ratio, providing a short electron transfer pathway in the optimized Z7A DS photodetector, which in turn demonstrated photo-responsivity and photo-detectivity of 6 mA/W and 1.7 × 10+10 Jones, respectively. This work presents an alternative approach for the design of an eco-friendly MMO-based DS photodetector. [Figure not available: see fulltext.]. © 2019, Springer Nature B.V
Modeling, simulation and control issues on standalone photovoltaic system
No full textFor application in the design and implementation of standalone PV solar electric application, as well as, control of its output characteristics and performance, to meet particular electric application requirements, different PV system models and corresponding control approaches are derived, built and tested in MATLAB/Simulink. The models and approaches were tested. For a given PV system design parameters with variable output from PV subsystem and under specific given PV system working conditions, all to control outputs characteristics of overall PV system, as well as, each subsystem output characteristics, all to meet overall PV system desired output characteristics, performance and meeting desired values of voltage and current. © International Research Publication House
A systems biology approach towards the identification of candidate therapeutic genes and potential biomarkers for Parkinson’s disease
No full textParkinson’s disease (PD) is an irreversible and incurable multigenic neurodegenerative disorder. It involves progressive loss of mid brain dopaminergic neurons in the substantia nigra pars compacta (SN). We compared brain gene expression profiles with those from the peripheral blood cells of a separate sample of PD patients to identify disease-associated genes. Here, we demonstrate the use of gene expression profiling of brain and blood for detecting valid targets and identifying early PD biomarkers. Implementing this systematic approach, we discovered putative PD risk genes in brain, delineated biological processes and molecular functions that may be particularly disrupted in PD and also identified several putative PD biomarkers in blood. 20 of the differentially expressed genes in SN were also found to be differentially expressed in the blood. Further application of this methodology to other brain regions and neurological disorders should facilitate the discovery of highly reliable and reproducible candidate risk genes and biomarkers for PD. The identification of valid peripheral biomarkers for PD may ultimately facilitate early identification, intervention, and prevention efforts as well. © 2019 Sakharkar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Investigation on gel polymer electrolyte-based dye-sensitized solar cells using carbon nanotube
No full textA new poly (acrylonitrile) (PAN)-based gel polymer electrolyte (GPE) is fabricated to study the effect of carbon nanotube (CNT) on dye-sensitized solar cell (DSSC) efficiency. The GPEs are examined using electrochemical impedance spectroscopy (EIS) to analyze ionic conductivity. A maximum of 4.45 mS cm −1 ionic conductivity is achieved at room temperature with incorporation of 11 wt.% CNT. Performance of DSSC is examined with a solar simulator, and the highest energy conversion efficiency of 8.87% is achieved with the addition of 11 wt.% CNT. All GPE samples are found to follow Arrhenius model with temperature-dependent ionic conductivity testing. Structural properties are also characterized by X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature
Personalized administration of contrast medium with high delivery rate in low tube voltage coronary computed tomography angiography
No full textBackground: High delivery rate is an important factor in optimizing contrast medium administration in coronary computed tomography angiography (CCTA). A personalized contrast volume calculation algorithm incorporating high iodine delivery rate (IDR) can reduce total iodine dose (TID) and produce optimal vessel contrast enhancement (VCE) in low tube voltage CCTA. In this study, we developed and validated an algorithm for calculating the volume of contrast medium delivered at a high rate for patients undergoing retrospectively ECG-gated CCTA with low tube voltage protocol. Methods: The algorithm for an IDR of 2.22 gI·s-1 was developed based on the relationship between VCE and contrast volume in 141 patients; test bolus parameters and characteristics in 75 patients; and, tube voltage in a phantom study. The algorithm was retrospectively tested in 45 patients who underwent retrospectively ECG-gated CCTA with a 100 kVp protocol. Image quality, TID and radiation dose exposure were compared with those produced using the 120 kVp and routine contrast protocols. Results: Age, sex, body surface area (BSA) and peak contrast enhancement (PCE) were significant predictors for VCE (P<0.05). A strong linear correlation was observed between VCE and contrast volume (r=0.97, P<0.05). The 100-to-120 kVp contrast enhancement conversion factor (Ec) was calculated at 0.81. Optimal VCE (250 to 450 HU) and diagnostic image quality were obtained with significant reductions in TID (32.1%) and radiation dose (38.5%) when using 100 kVp and personalized contrast volume calculation algorithm compared with 120 kVp and routine contrast protocols (P<0.05). Conclusions: The proposed algorithm could significantly reduce TID and radiation exposure while maintaining optimal VCE and image quality in CCTA with 100 kVp protocol. © Quantitative Imaging in Medicine and Surgery. All rights reserved
A novel and non‐invasive approach utilising nasal washings for the detection of nasopharyngeal carcinoma
No full textNasopharyngeal carcinoma (NPC) is an epithelial cancer of the nasopharynx which is highly associated with Epstein–Barr virus (EBV). Worldwide, most of the top 20 countries with the highest incidence and mortality rates of NPC are low- and middle-income countries. Many studies had demonstrated that EBV could be detected in the tissue, serum and plasma of NPC patients. In this study, we explored the potential of assays based on non-invasive nasal washings (NW) as a diagnostic and prognostic tool for NPC. A total of 128 patients were evaluated for NW EBV DNA loads and a subset of these samples were also tested for 27 EBV and human miRNAs shortlisted from literature. EBV DNA and seven miRNAs showed area under the receiver operating characteristic curve (AUC) values of more than 0.7, suggestive of their potential utility to detect NPC. Logistic regression analyses suggested that combination of two NW assays that test for EBNA-1 and hsa-miR-21 had the best performance in detecting NPC. The trend of NW EBV DNA load matched with clinical outcome of 71.4% (10 out of 14) NPC patients being followed-up. In summary, the non-invasive NW testing panel may be particularly useful for NPC screening in remote areas where healthcare facilities and otolaryngologists are lacking, and may encourage frequent testing of individuals in the high risk groups who are reluctant to have their blood tested. However, further validation in an independent cohort is required to strengthen the utility of this testing panel as a non-invasive detection tool for NPC. © 2019 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UIC
Preventing delayed cracks in SUS304 deep drawn cups using extreme blank holding forces aided by nanolubrication
No full textDisappearance and reappearance of delayed cracks were observed in deep drawing process of SUS304 cylindrical cups under elevated blank holding forces (BHF) of 8~32 kN with nanolubricants containing 1~3 wt% SiO 2 concentrations at limiting draw ratio. The widest crack-free BHF range determined experimentally, i.e., 29~31 kN was for 2 wt% SiO 2 . Delayed cracks were observed below and beyond this BHF range. The frictional force at the flange surfaces slightly increased when entering the crack-free BHF range, as evidenced by the rebound in sidewall thickness, relative intensity of α′-martensite, elongated height, and drawing force beyond 28 kN. The coefficients of friction for each BHF were obtained with finite element simulations. Since residual stresses developed along the outer surface of the cup due to the unbending of the material when the material left the draw die profile, the slight increase in frictional force in the radial direction along the flange surfaces reduced the circumferential tensile residual stress of the cup, particularly at 80% cup height. The elimination of delayed cracks was attributed to the lower tensile residual stress gradient, i.e., lower and higher tensile residual stresses at 80% and 100% cup heights, respectively. However, the excessive increase at 100% cup height was a result of the increase in longitudinal compressive stress at BHF beyond 31 kN due to the stress equilibrium, leading to the reappearance of cracks. The minimum BHF required to eliminate cracks changed minimally with increasing SiO 2 concentration. © 2018, Springer-Verlag London Ltd., part of Springer Nature