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Lower and upper flammability limits (LFL and UFL) are widely and effectively used as simple safety boundaries for preventing gas-mixture ignition, and predicting them for new compounds would be valuable, especially the LFLs for low-flammability non-C/H/O species. Prediction with mechanistic flame models uses the idea that as these limits are reached, the flame speed and temperature drop below a threshold of flame feasibility because of radiant heat loss. Using methane as a reference study because its mechanisms and flammability are well characterized, non-adiabatic laminar flame speeds and profiles of temperature, flame structure, and chemiluminescent OH* and CH* are calculated using a modification of the hydrocarbon kinetics model of Hashemi et al. (2016), executed in CHEMKIN and Cantera. LFL prediction is emphasized here; large-hydrocarbon and soot radiant losses have been proven to be necessary for accurate UFL values (Bertolino et al., 2019) but were not included in this work. Property dependences on concentration are compared to published flammability limits of 5–15% methane concentration for methane/air mixtures at T 0 = 298 K and 1, 5, and 10 atm. At 1 atm, the LFL occurs at a laminar flame speed of 2.7 cm/s, and at the UFL, flame speeds between 4.5 and 6 cm/s correspond to the limit. Similarly, adiabatic temperature of 1450 K in a fuel-lean environment and 1560–1670 K in a fuel-rich environment correlate with the flammability limits. The ASTM standard test for flammability uses visual detection of a flame; ultraviolet chemiluminescence of OH* radical at limits of less than mole fraction of 10−3 is shown to reflect the methane LFL, and the equivalence-ratio dependence of OH* should resemble that of the visible C2* emission. Effects of pressure and challenges for modeling are discussed.

Objective Premature and ill neonates undergo painful but medically necessary procedures while hospitalized. Although opiate drugs are administered as analgesics, problems associated with their side effects, tolerance, and potential dependence necessitate research into alternative pain-relieving medications. Here we test two plant-derived compounds in infant rats: sinomenine, which targets the Mas-related G-protein-coupled receptor member X2 opioid receptor; and salvinorin A, which is a κ opioid receptor agonist. In adult animals both sinomenine and salvinorin A are analgesic, but neither has been tested in infants. Methods We used the formalin and thermal plantar tests in rats 7 and 21 days of age (PN7 and PN21) for behavioral signs of pain. In addition, brain sections were stained using Fos immunohistochemistry to examine patterns of brain activation in the midbrain periaqueductal gray and the paraventricular nucleus of the hypothalamus. Results Sinomenine was analgesic in both the formalin and thermal tests on animals 21 days of age. At PN7 only the highest dose elevated response latencies in the thermal test and there were no effects of sinomenine in the formalin test. Analysis of Fos expression in the sinomenine-treated animals showed no drug effect, in contrast to the behavioral results. Salvinorin A was analgesic in the formalin test only at the highest dose at 21 days of age but not in the thermal test at either age. Conclusion The increased modest effectiveness of sinomenine in older animals and the minimum salvinorin A drug effect suggest that the compounds act on sites that develop during the preweaning period (sinomenine) or after weaning (salvinorin A).

Tizanidine hydrochloride (TZD) is a muscle relaxant and alpha2 adrenergic agonist. TZD overdose possesses some potentially unwanted side effects including hallucinations, delusion, low blood pressure, liver damage, etc. Thus, the development of an analytical method for the sensitive detection of TZD in clinical and real samples is essential. Zinc oxide (ZnO) is a non-hazardous material and its amazing surface properties, and wide bandgap makes it a good modifier for electrochemical sensor development. In the present work, a novel sensor system is developed for the electrochemical determination of TZD. The fabrication of the glassy carbon electrode (GCE) was done by the drop cast method, where suspension of ZnO was coated on the sparkling surface of the GCE. Voltammetric investigation of TZD was performed by employing cyclic voltammetry (CV), linear sweep voltammetry (LSV), and square wave voltammetry (SWV) techniques. The electroanalytical study of TZD shows one peak in the forward scan indicating the irreversibility of TZD at bare GCE and ZnO/GCE. In comparison to bare GCE, sensitive detection with a higher peak current was obtained at the modified electrode, due to the increase in the active surface area. Optimization of the amount of modifier, accumulation time, and pH of the electrolyte was done methodically. The analytical performance of the fabricated sensor towards TZD detection was investigated by using the SWV technique, and the limit of detection was found to be 1.15 × 10−8 M. To check the effectiveness and real-time application, the developed electrode was assessed in the detection of TZD in commercially available pharmaceutical formulations and TZD spiked human urine samples. The fabricated sensor has also shown a sensitive detection and higher % recovery values, indicating its direct commercial and clinical importance.

The electrochemical oxidation of Ferulic acid (FA) was assiduously scrutinized by cyclic voltammetry and more sensitive amperometry technique using silver decorated multi-walled carbon nano-tubes modified carbon paste electrode. The modified electrode showed superior catalytic activity at physiological pH. The synergistic outcome of multiwalled carbon nano-tubes and silver nano-particles resulted in superior electro-catalytic activity and a significant three time increase of anodic peak current sensitivity and a remarkable lower energetics by 120 mV shift in potential thereby decreasing over-potential for electro-oxidation of FA in comparison to bare carbon paste electrode. Under optimized conditions, a linear dynamic range of 4.0 × 10− 8 to 1.0 × 10− 3 M, with a lower detection limit of 3.0 × 10− 8 M (S/N = 3) was obtained. The surface morphology of the sensor was studied using field emission scanning electron microscopy and atomic force microscopy. EDX was used determine the elemental composition of the electrode. The electrochemical impedance study revealed the least charge transfer resistance for the modified electrode. The effect of variation of scan rate, pH and concentration towards the electro-catalytic oxidation of FA was also investigated. Absence of peak for interfering molecules like Ascorbic acid, Uric acid and Glucose makes this sensor unique with significant analytical advantage. The fabricated sensor revealed adequate reproducibility, long term stability and enhanced selectivity in presence of commonly existing interfering molecules. The sensor was employed for the validation of spiked human urine and the wine which gave recoveries ranging from 97.5 to 99.4%, making it a potential alternative tool for the quantitative detection of FA in the biomedical field.

The fossil fuel issues due to toxic carbon dioxide emissions and climate change have a direct link with the particulate matter that has caused severe threat to the environment. The bio-based products such as biodiesel and bio-compressed natural gas (Bio-CNG) can be less expensive and adaptable. Biofuels are increasingly being used in transportation, heat, and power development requiring the need for renewable sources of energy. This review highlights the use of dreck organic matters from aquatic environment and soil supplies for renewable energy production for human requirements, sustaining a clean and healthy environment. Dreck can be harnessed to manufacture bioenergy that would help to mitigate greenhouse gases and preserve the environment. Methane, hydrogen, ethanol, bioelectricity, algal diesel, and butanol, or other forms of fuels provide a renewable supply of bioenergy, which can be created by the biological systems. The waste-to-energy methodologies (thermal plus biochemical) for energy production via agro-residues are covered. The key focus of this study is the recent advances in the area of 'synchronous waste mitigation with energy development' techniques. This review addresses the significance of organic substances for the production of clean and renewable energy, including alternate solutions for non-renewable fuels. The needs for appropriate and renewable alternatives for fossil fuels are discussed.

An amperometric sensor was developed based on multi-walled carbon nanotubes and poly (Bromocresol purple) modified carbon paste electrode, for the sensitive investigation of L-Tyrosine (Tyr). The surface morphology of the electrodes was studied using field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) while electron impedance spectroscopy (EIS) was employed to throw light on electrode – electrolyte interface properties. The symbiotic effect of the bulk modification and electro-polymerization was evident by 5.5 times increase in the peak current compared to the bare carbon paste electrode (CPE). Cyclic voltammetry (CV) technique was used for the qualitative analysis of Tyr at the modified electrode. The amperometric results showed that the anodic current was proportional to the Tyr concentration in ranges of 2.0 μM–100.0 μM with a lower detection limit of (1.91 ± 0.27) × 10−7 M (signal/noise = 3) at physiological pH. The CV and amperometric response of Tyr was examined in the presence of co-existing bio-molecules and the results indicated that the electrode had good anti-interference ability and could be subjected easily to real sample analysis. The low cost, high sensitivity, stability, reproducibility and anti-interference ability of the sensor offer an avenue to broaden its applications. The sensor was also tested for its practical applications by spiking Tyr in milk and blood serum samples and the recoveries obtained were found to be satisfactory.

We have developed a nanodevice with the aid of adsorption strategy. The key factor being the extensive π-π interactions between sp 2 carbons of nano-Graphene-platelets (nGp) and π-e- of cationic Brilliant green (Bg) at the electrode surface, that synergistically promoted Hesperidin (HES) oxidation. From our observations, electrochemical catalytic oxidation of HES significantly magnified on nGp-Bg/Modified carbon paste electrode (nGp-Bg/MCPE), under optimized experimental conditions, such as the volume of composite cast-coated, cationic active sites in the nGp-Bg film, and the pH of the buffer. Surface morphology was characterized using Field Emission Scanning Electron Microscopy (FESEM) and Electron Diffraction X-ray (EDX). Nyquist plots revealed the least charge transfer resistance at nGp-Bg/MCPE compared to other control electrodes. Further, at physiological pH, HES displayed an irreversible electrochemical charge transfer at nGp-Bg/MCPE. The cationic Bg moieties on nGp-Bg/MCPE portrayed a great affinity towards deprotonated HES and its accumulation on the electrode surface. Interactions between aromatic rings in nGp-Bg structure and HES molecules consequently enhanced total surface coverage concentration by 3.6-fold compared to control electrodes via adsorption-controlled-electron-transfer feature. We have demonstrated that the reaction capability of nGp-Bg/MCPE towards HES quantification via synergistic electrocatalytic effect, with the ability to lower the activation energy and hastened oxidation. Quantification of HES was performed using Differential Pulse Voltammetry (DPV). Gp-Bg/MCPE showed selective mediated oxidation current response with the lowest detection limit of 5.0 × 10 −8 M in two linear ranges. We have successfully validated trace analysis of HES in fortified fruit juice samples, also extendable to various practical applications. Therefore, the present work has established simplicity in the principle of the novel approach in the development of an ultrasensitive voltammetric sensor for HES.

Psidium guajava extract is sold as a dietary supplement for delaying the onset of various diseases. It has been reported to have exemplary antioxidant properties. Herein we report an electrochemical sensor for the detection of Morin (MR) for the first time in Psidium guajava leaf extract which has been reported to have MR. Nickel (II) phthalocyanine (NiPc) complex is used in the surface modification of the carbon paste electrode (CPE) by bulk modification method and characterized by spectroscopic techniques. Combining the favorable properties of NiPc and CPE assembles into a formidable sensor for facile quantification of biomolecules. We observed a significant electroactivity at the modified electrode with a notable twelvefold enhancement in anodic peak current at physiological pH. A wide linear dynamic range of 2.5 × 10−3 to 1.0 × 10−7 M, with a limit of quantification and limit of detection achieved, was 6.9 nM and 2.0 nM (S/N = 3) respectively. The proposed sensor could resolve the peaks of quercetin and morin effortlessly and simultaneously. The proposed biosensor is swift, simple to fabricate, with low limits of detection and remarkable antifouling properties. The sensor was used in the validation of spiked red wine, human urine, tea decoction and commercially available guava leaf capsules, with satisfactory recoveries.

Iron nanoparticles decorated multi-wall carbon nanotubes modified carbon paste electrode (Fe-MWCNTs/MCPE) was prepared by bulk-modification method. The electrochemical impedance spectroscopy (EIS) suggests least charge transfer resistance at the modified electrode. The electrochemical behavior of UA was studied in 0.1M phosphate buffer solution (PBS) of pH3.0 using cyclic voltammetry (CV) while differential pulse voltammetry (DPV) was used for quantification. The spectroelectrochemial study of oxidation of UA at Fe-MWCNTs/MCPE showed a decrease in the absorbance of two peaks with time, which are ascribed to π to π(⁎) and n to π(⁎) transitions. Under optimum condition, the DPV response offered two linear dynamic ranges for UA in the concentration range 7.0×10(-8)M-1.0×10(-6)M and 2.0×10(-6)M-1.0×10(-5)M with detection limit (4.80±0.35)×10(-8)M (S/N=3). The practical analytical application of this sensor was successfully evaluated by determination of spiked UA in clinical samples, such as human blood serum and urine with good percentage recovery. The proposed electrochemical sensor offers a simple, reliable, rapid, reproducible and cost effective analysis of a quaternary mixture of biomolecules containing AA, DA, UA and Tyr which was free from mutual interferences.

Enhanced sensitivity and electro-catalytic activity for the sensor was achieved by incorporating platinum decorated multi-walled carbon nanotubes (PtMWCNTs) into the carbon paste matrix and TritonX-100 (TX100) layered onto its surface. The modification of carbon paste electrode (CPE) using PtMWCNTs and TX100 was accomplished by employing bulk modification and drop cast methods, respectively. The electrochemical behaviour of Paracetamol (PA) at PtMWCNTs and TX100 modified CPE was investigated by cyclic voltammetry and amperometry. The electrode sensitivity for PA has shown significant variation on varying the amount of Pt nanoparticles on MWCNTs and the PtMWCNTs content in carbon paste matrix. The influence of variation of concentration, volume and time of adsorption of TX100 on the response of PA was investigated. The developed sensor was employed for the selective detection of PA using hydrodynamic amperometry at physiological pH in the presence of ascorbic acid (AA), dopamine (DA) and tryptophan (Trp). The surface morphology of the electrode was studied using FE-SEM images and the interface properties of bare and modified electrodes were investigated by electrochemical impedance spectroscopy. PtMWCNTs in combination with TX100 resulted in an impressive enhancement in the redox current with an analytical advantage of complete elimination of the interference of AA in the simultaneous determination of PA in a mixture. A lower detection limit of (17.71 ± 2.03) nM ( S / N = 3) was achieved for PA. The modified electrode showed excellent reproducibility, long-term stability and antifouling effects. The practical analytical application was demonstrated by carrying out determination of PA in real samples.

Ruxolitinib, a selective JAK1/JAK2 inhibitor, is the current first line therapy for myelofibrosis (MF), which reduces symptomatology and splenomegaly, but does not clearly modify disease course. Panobinostat, a histone deacetylase inhibitor, was shown to be safe and tolerable in phase I and II trials and demonstrated clinical activity in approximately a third of treated patients. Combination therapy of ruxolitinib and panobinostat showed synergistic activity in a preclinical MF model, which prompted clinical evaluation of this combination in both ruxolitinib naïve and treated MF patients. Herein, we report the results of an investigator-initiated, dose escalation, phase I trial of ruxolitinib and panobinostat in 15 patients with primary MF and post-polycythemia vera/essential thrombocythemia MF. This combination treatment proved to be safe and tolerable without dose limiting thrombocytopenia and a maximum tolerated dose of both agents in combination was not determined. The majority of patients maintained stable disease with this combination treatment and 40 % attained a clinical improvement (spleen n = 5, anemia n = 1) by modified IWG-MRT at the end of 6 cycles. This is one of the first attempts of rationally designed, JAK inhibitor-based, combination therapy studies and exemplifies the feasibility of such an approach in patients with advanced MF.

A modified carbon paste electrode (CPE) for the selective detection of dopamine (DA) in presence of large excess of ascorbic acid (AA) and uric acid (UA) at physiological pH has been fabricated by bulk modification of CPE with multi-walled carbon nanotubes (MWCNTs) followed by electropolymerization of glycine (Gly). The surface morphology is compared using SEM images. The presence of nitrogen was confirmed by the energy dispersion X-ray spectroscopy (EDS) indicating the polymerization of Gly on the surface of the modified electrode. The impedance study indicates a better charge transfer kinetics for DA at CPE modified with MWCNT/polyglycine electrode. The presence of MWCNTs in carbon paste matrix triggers the extent of electropolymerization of Gly and imparts more selectivity towards DA by electrochemically not sensing AA below a concentration of 3.1×10-4M. Due to the exclusion of the signal for AA, the interference of AA in the determination of DA is totally ruled out by DPV method which is used for its detection at lower concentrations. Large peak separation, good sensitivity, reproducibility and stability allow this modified electrode to analyze DA individually and simultaneously along with AA and UA. Detection limit of DA was determined from differential pulse voltammetric (DPV) study and found to be 1.2×10-8M with a linear dynamic range of 5.0×10-7M to 4.0×10-5M. The practical analytical application of this electrode was demonstrated by measurement of DA content in dopamine hydrochloride injection and human blood serum.

An electrochemical sensor for the selective detection of dopamine was developed by the electropolymerization of Rhodamine B dye at a carbon paste electrode. Under physiological conditions, the modified electrode was able to resolve the voltammetric peak of dopamine from all interfering species whose concentrations were thousand folds more than that of dopamine. A wide linear dynamic range of 6–1000 μM and a detection limit of 3.99 × 10− 6 M were observed for dopamine. The main advantage of the modified electrode using differential pulse voltammetric technique is its inability to sense the presence of micro-molar levels of ascorbic acid and uric acid while it can detect dopamine at the micro-molar level. This unique property of the modified electrode eliminates the possible interferences of low concentrations of ascorbic acid while also making it more sensitive and convenient to use as a sensor for the detection of low concentrations of dopamine in real samples. Satisfactory results were obtained while the modified electrode was employed for determination of dopamine in human blood serum and dopamine hydrochloride injection. The electrode showed excellent reproducibility, selectivity and antifouling effects.

A novel electrochemical sensor for the selective and sensitive detection of dopamine (DA) in presence of large excess of ascorbic acid (AA) and uric acid (UA) at physiological pH was developed by the bulk modification of carbon paste electrode (CPE) with biocompatible graphite oxide (GO). Very small quantity of GO in carbon paste matrix imparted selectivity through electrostatic interactions. The modifier was characterized using infrared spectroscopy and powder X-ray diffraction. Large peak separation, good sensitivity and stability allow this modified electrode to analyze DA individually and simultaneously along with AA and UA. Applying differential pulse technique, DA could be detected even in the presence of 1000 fold excess of AA and UA. A linear dynamic range of 0.07–70 μM with detection limit of 1.5 × 10 −8 M was obtained for DA. None of the bulk modified electrodes reported in the literature have shown such a low detection limit at the physiological pH. The practical application of the modified electrode was demonstrated by spiking the human blood serum and cerebral fluid with dopamine and the results obtained were satisfactory.

The deposition and stripping processes of lead and copper and cadmium ions over the wide concentrations range of 1 × 10 −5 to 5 × 10 −9 M, have been studied at mercury film deposited on wax impregnated carbon paste electrode, using cyclic voltammetry, linear sweep anodic stripping voltammetry and differential pulse anodic stripping voltammetry. The carbon paste electrode modified with the mercury film was characterized for its physical and electrochemical properties. The parameters of deposition and stripping processes of the analytes have been investigated using standard solution of the metal ions at various concentrations and different supporting electrolytes and different pH. The linear sweep anodic stripping has been adopted for the determination of analytes at higher concentration whereas the analytes at lower concentrations were determined using DPASV. The DPASV behavior for the ions studied dependent on concentrations of the analyte as well as on the time used in the pre-concentration step. The method developed using standard solutions have been successfully applied for the determination of Cu(II), Pb(II) and Cd(II) in Fin Fish muscles and water samples.

The study analyzes medical residents (MRs) attitudes on the ethics of information disclosure in two case scenarios—HIV disease and cancer. A purposeful sample of 120 MRs took part in a self-completion questionnaire administered. Responses were factor analyzed and three factors (17 statements) protecting rights of (1) spouse/family, (2) patient and (3) society, were retained for study. Analysis revealed that: (1) MRs perceived greater justification (P