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Revalorization of selected municipal solid wastes as new precursors of “green” nanocellulose via a novel one-pot isolation system: A source perspective
No full textIn the present work, four types of newly chosen municipal solid wastes (Panax ginseng, spent tea residue, waste cotton cloth, and old corrugated cardboard) were studied as the promising sources for nanocellulose, which has efficiently re-engineered the structure of waste products into highly valuable nanocellulose materials. The nanocellulose was produced directly via a facile one-pot oxidative hydrolysis process by using H2O2/Cr(NO3)3 solution as the bleaching agent and hydrolysis medium under acidic condition. The isolated nanocellulose products were well-characterized in terms of chemical composition, product yield, morphological structure and thermal properties. The study has found that the crystallinity index of the obtained nanocellulose products were significantly higher (62.2–83.6%) than that of its starting material due to the successive elimination of lignin, hemicellulose and amorphous regions of cellulose, which were in good agreement with the FTIR analysis. The evidence of the successful production of nanocellulose was given by TEM observation which has revealed the fibril widths were ranging from 15.6 to 46.2 nm, with high cellulose content (>90%), depending on the cellulosic origin. The physicochemical properties of processed samples have confirmed that the isolation of high purity nanocellulose materials from different daily spent products is possible. The comparative study can help to provide a deep insight on the possibility of revalorizing the municipal solid wastes into nanocellulose via the simple and versatile one-pot isolation system, which has high potential to be used in commercial applications for sustainable development
Comparison of clinical performance of size 1.5 Supreme™ LMA and Proseal™ LMA among Asian children: a randomized controlled trial
No full textTo date, most of the studies on safety and efficacy of supraglottic airway devices were done in Caucasian patients, and the results may not be extrapolated to Asian patients due to the different airway anatomy. We conducted this study to compare Supreme™ LMA (SLMA) and Proseal™ LMA (PLMA) size 1.5 in anaesthetized children among an Asian population. This prospective randomized clinical trial was conducted in a tertiary teaching hospital from September 2013 until May 2016. Sixty children, weighing 5–10 kg, who were scheduled for elective surgery under general anaesthesia were recruited and completed the study. Patients were randomly assigned to have either SLMA or PLMA as the airway device for general anaesthesia, and standard anaesthesia protocol was followed. The primary outcome measured was the oropharyngeal leak pressure (OLP). The rate of successful insertion, insertion time, fibreoptic view of larynx and airway complications for each device were also assessed. There were no statistically significant differences between SLMA and PLMA size 1.5 in oropharyngeal leak pressure [19.1 (± 5.5) cmH2O vs. 19.8 (± 4.5) cmH2O, p = 0.68]. Secondary outcomes including time to insertion [20.8 (± 8.3) vs. 22.1 (± 8.3) s, p = 0.57], first attempt success rate for device insertion, fibreoptic view of larynx, and airway complications were also comparable between the two devices. We found that all the patients who had a failed device insertion (either PLMA or SLMA) were of a smaller size (5–6.2 kg). The oropharyngeal leak pressure of the SLMA 1.5 was comparable with the PLMA 1.5, and both devices were able to maintain an airway effectively without significant clinical complications in anaesthetized children from an Asian population
Long-term exposure to insulin and volumetric mammographic density: observational and genetic associations in the Karma study
No full textBackground: Long-term insulin exposure has been implicated in breast cancer etiology, but epidemiological evidence remains inconclusive. The aims of this study were to investigate the association of insulin therapy with mammographic density (MD) as an intermediate phenotype for breast cancer and to assess associations with long-term elevated circulating insulin levels using a genetic score comprising 18 insulin-associated variants. Methods: We used data from the KARolinska MAmmography (Karma) project, a Swedish mammography screening cohort. Insulin-treated patients with type 1 (T1D, n = 122) and type 2 (T2D, n = 237) diabetes were identified through linkage with the Prescribed Drug Register and age-matched to 1771 women without diabetes. We assessed associations with treatment duration and insulin glargine use, and we further examined MD differences using non-insulin-treated T2D patients as an active comparator. MD was measured using a fully automated volumetric method, and analyses were adjusted for multiple potential confounders. Associations with the insulin genetic score were assessed in 9437 study participants without diabetes. Results: Compared with age-matched women without diabetes, insulin-treated T1D patients had greater percent dense (8.7% vs. 11.4%) and absolute dense volumes (59.7 vs. 64.7 cm3), and a smaller absolute nondense volume (615 vs. 491 cm3). Similar associations were observed for insulin-treated T2D, and estimates were not materially different in analyses comparing insulin-treated T2D patients with T2D patients receiving noninsulin glucose-lowering medication. In both T1D and T2D, the magnitude of the association with the absolute dense volume was highest for long-term insulin therapy (≥ 5 years) and the long-acting insulin analog glargine. No consistent evidence of differential associations by insulin treatment duration or type was found for percent dense and absolute nondense volumes. Genetically predicted insulin levels were positively associated with percent dense and absolute dense volumes, but not with the absolute nondense volume (percentage difference [95% CI] per 1-SD increase in insulin genetic score = 0.8 [0.0; 1.6], 0.9 [0.1; 1.8], and 0.1 [- 0.8; 0.9], respectively). Conclusions: The consistency in direction of association for insulin treatment and the insulin genetic score with the absolute dense volume suggest a causal influence of long-term increased insulin exposure on mammographic dense breast tissue
A Fuzzy Logic Controller Based on Maximum Power Point Tracking Algorithm for Partially Shaded PV Array-Experimental Validation
No full textIn the last two decades, the maximum power point tracking (MPPT) methods for PV system is becoming very interesting subject. Among these methods there is Fuzzy-MPPT, which is mainly based on two inputs and at least 25 rules. This structure need more calculation time and not easy to be implemented in hardware. For these reasons and in order to facilitate the MPPT synthesis, this paper proposes an intelligent MPPT controller based on a single-input Takagi-Sugeno fuzzy logic controller (SI-TS-FLC) with three linguistic variables and three rules. The proposed controller is simulated using MATLAB-SIMULINK for a PV system, which consists of a PV generator, DC-DC converter, and resistive load under varied temperature and irradiance levels. An experimental study is conducted using DSPACE 1104 card real-time board under partial shading condition. Simulation and experimental results show that the proposed controller exhibits less settling time and lower overshoot than the commonly used perturb and observe (P&O) algorithm in the transient state and minimum oscillation around the optimal operating point
Structural characterization of copper (II) tetradecanoate with 2,2′-bipyridine and 4,4′-bipyridine to study magnetic properties
No full textThis paper presents synthesis, structural characterization and spintronic applications of copper (II) tetradecanoate derived magnetic complexes. The complexes were prepared by a chemical reaction between [Cu2(CH3(CH2)12COO)4](EtOH)2 and 2,2′-bipyridine-4,4′-bipyridine ligands respectively. The complexes were further reacted between the product of the first reaction and 4,4′-bipyridine-2,2′-bipyridine respectively. The structural characterization techniques included elemental analysis, Fourier transformed infrared spectroscopy (FTIR), Ultra-violet–Visible (UV–Vis) spectroscopy, polarized optical microscopy, magnetic moment and thermogravimetric analysis. The structural and characterization results suggested that the synthesized complexes were binuclear and mononuclear covalent complexes of copper(II) with structural formulas [Cu2(η2-(OOCR)4](4,4′-bpy)2H2O] and [Cu(η1-(OOCR)2(2,2′-bpy) (4,4′-bpy)] respectively
Pricing convertible bonds
No full textConvertible bonds are an important segment of the corporate bond market although their pricing is compromised by the presence of complex option features and difficulty in measuring the risk factors needed as inputs to standard valuation models. Using a unique sample of pure U.S. convertible bonds, devoid of other optionality, we show that underpricing is affected mainly by the degree of underlying asset volatility and liquidity. Convertible bonds with a greater debt component (more credit sensitive), longer time to maturity and lower quality credit ratings are also found to be more underpriced. The global financial crisis (GFC) is an episode with high-underlying asset volatility and one subject to short-selling constraints. During this period there was deep convertible bond discounting, which highlights the importance of market conditions and the temporal, rather than systematic, nature of the pricing errors
Antiemetic doses of dexamethasone and their effects on immune cell populations and plasma mediators of inflammation resolution in healthy volunteers
No full textIntroduction: The synthetic glucocorticoid dexamethasone is a commonly administered antiemetic. It has immunosuppressive effects and may alter postoperative blood glucose concentrations. Dexamethasone can effect key enzymes involved in inflammation resolution that is an active process driven by specialised lipid mediators of inflammation resolution (SPM). The purpose of this study in healthy volunteers was to examine whether dexamethasone effects cell populations and synthesis of SPM that are critical for the resolution of inflammation. Methods: Thirty-two healthy volunteers were randomly allocated to receive saline (Control) or dexamethasone 2 mg, 4 mg or 8 mg intravenously. Venous blood samples were collected at baseline before administration of treatment, and at 4 h, 24 h and one-week post-treatment. At each time point, measurements included blood glucose and macrophage migration inhibition factor (MMIF), full blood count including lymphocyte subsets, monocytes, neutrophils, eosinophils and basophils by flow cytometry, and plasma SPM using liquid chromatography tandem mass spectrometry. The effect of dexamethasone dose and time on all measures was analysed using linear mixed models. Results: There was a dose-dependent increase in neutrophil count after dexamethasone that persisted for 24 h. In contrast, there was a dose-dependent reduction in counts of monocytes, lymphocytes, basophils and eosinophils 4 h after dexamethasone, followed by a rebound increase in cell counts at 24 h. Seven days after administration of dexamethasone, all cell counts were similar to baseline levels. MMIF concentration, glucose and natural killer cell counts were not significantly affected by dexamethasone. There was a significant gender effect on plasma SPM such that levels of 17-HDHA, RvD1, 17R-RvD1 and RvE2 in females were on average 14%–50% lower than males. In a linear mixed model that adjusted for neutrophil count, there was a significant interaction between the dose of dexamethasone and time, on plasma 17R-RvD1 such that plasma 17R-RvD1 fell in a dose-dependent manner until 4 h after administration of dexamethasone. There were no significant effects of dexamethasone on the other plasma SPM (18-HEPE, RvE2, 17-HDHA, RvD1, RvD2 and 14-HDHA) measured. Discussion: This is the first study in healthy volunteers to demonstrate that commonly employed antiemetic doses of dexamethasone affect immune cell populations and plasma levels of 17R-RvD1 an SPM with anti-nociceptive properties. If similar changes occur in surgical patients, then this may have implications for acute infection risk in the post-operative period
Self-esteem, empathy and their impacts on cyberbullying among young adults
No full textThis paper investigated the impacts of self-esteem and empathy on cyber bullies, victims and bystanders. Additionally, it also examined their impacts on emotional responses experienced, and actions taken by the perpetrators, victims and bystanders. Self-administered surveys were used to gather data from a large sample of 1263 young adults, mostly university students in Malaysia (Mage = 20.9 years; SD = 1.22). The Rosenberg Self-Esteem Scale and Toronto Empathy Scale were used to measure self-esteem and empathy, respectively. Binary logistic regressions revealed no significant impacts of self-esteem and empathy on the participants, regardless of their roles. However, self-esteem was found to have significant relationships with victims’ feeling angry and reporting a cyberbullying incident. As for bystanders, self-esteem also had significant relationships with feeling angry, sad, victim-pity and defending the victims. Empathy had no significant relationships with any of the actions and emotional responses for bullies, victims and bystanders
Multi-Objective Network Reconfiguration with Optimal DG Output Using Meta-Heuristic Search Algorithms
No full textNetwork reconfiguration is a well-known technique for the distribution system to reduce power losses. However, the reconfiguration technique, by itself, could only minimize power losses up to a certain point. Further power losses reduction could be realized via the application of distributed generation (DG). However, the integration of DG to the distribution system at a non-optimal value could instead increase power losses and voltage fluctuation. Therefore, it is vital to develop an effective optimization strategy to determine the optimal output of the DG and simultaneously ensure optimal configuration. This paper presents a simultaneous optimal network reconfiguration with optimal DG output to minimize power losses and improve the voltage profile. Different objectives are discussed in this paper: (1) to minimize power losses, (2) to improve voltage profile index, (3) to maximize DG output. Evolutionary programming, particle swarm optimization, firefly, and gravitational search algorithm methods have been applied for optimal distribution network reconfiguration with optimal DG output. To evaluate the possibilities of the suggested method, simulations using MATLAB software are carried out on an IEEE 33-bus radial distribution system. The obtained outcomes prove the efficiency of the proposed strategy to find an optimal network configuration and optimal output of DG units
Electrodeposited Nickel Cobalt Sulfide Flowerlike Architectures on Disposable Cellulose Filter Paper for Enzyme-Free Glucose Sensor Applications
No full textThree-dimensional flowerlike nickel cobalt sulfide (NiCo2S4) nanostructures are electrochemically deposited over the Ni-modified cellulose filter paper (CFP). The fabricated NiCo2S4/Ni/CFP is explored as a binder-free and self-standing electrode for enzyme-free electrochemical detection of glucose in alkaline media, in which Ni/CFP and NiCo2S4 serve as the current collector and active material, respectively. Owing to the rich redox active sites, synergistic effect between Co4+ and Ni3+, and rapid electron transportation tuned with the substitution of sulfur (S) with oxygen labile functional group, NiCo2S4/Ni/CFP exhibits considerable enzyme-free glucose-sensing performance with wide linear glucose concentration ranging from 0.5 μM to 6 mM, high sensitivity of 283 μA mM-1 cm-2, and low detection limit of 50 nM. The developed NiCo2S4/Ni/CFP's sensing performances are reproducible, stable, and highly selective toward the analyte of interest in physiological interfering species. Thus, the self-standing, binder-free, inexpensive, easily disposable, and facile electrode fabrication process proposed in this study opens a new paradigm architecture for the development of efficient electrochemical sensor devices with affordable cost