•CO gas sensing response studies of the rf magnetron sputtered ZnO thin films have been performed using SPR.•The effect of deposition temperature on the structural, surface morphological, and gas ...sensing properties of ZnO thin film have been studied.•The developed sensor shows a quick response (1s) and high sensitivity (0.091°/ppm) towards CO gas.
Optical gas sensors provide an alternative over the conventional conductometric gas sensors. Carbon monoxide (CO) gas is generally regarded as one of the most dangerous air pollutants, hence, a room temperature operated CO gas sensor using ZnO sensing film deposited on Au coated prisms has been developed using an indigenously developed surface plasmon resonance (SPR) measurement setup. This system is found to be highly sensitive with very fast response towards a wide concentration range (0.5–100ppm) of CO gas at room temperature and hence pave way for commercial application of an efficient optical CO gas sensor.
Alcohol is a well‐established teratogen that can cause variable physical and behavioral effects on the fetus. The most severe condition in this spectrum of diseases is known as fetal alcohol syndrome ...(FAS). The differences in maternal and fetal enzymes, in terms of abundance and efficiency, in addition to reduced elimination, allow for alcohol to have a prolonged effect on the fetus. This can act as a teratogen through numerous methods including reactive oxygen species (generated as by products of CYP2E1), decreased endogenous antioxidant levels, mitochondrial damage, lipid peroxidation, disrupted neuronal cell–cell adhesion, placental vasoconstriction, and inhibition of cofactors required for fetal growth and development. More recently, alcohol has also been shown to have epigenetic effects. Increased fetal exposure to alcohol and sustained alcohol intake during any trimester of pregnancy is associated with an increased risk of FAS. Other risk factors include genetic influences, maternal characteristics, for example, lower socioeconomic statuses and smoking, and paternal chronic alcohol use. The treatment options for FAS have recently started to be explored although none are currently approved clinically. These include prenatal antioxidant administration food supplements, folic acid, choline, neuroactive peptides, and neurotrophic growth factors. Tackling the wider impacts of FAS, such as comorbidities, and the family system have been shown to improve the quality of life of FAS patients. This review aimed to focus on the pathogenesis, especially mechanisms of alcohol teratogenicity, and risks of developing FAS. Recent developments in potential management strategies, including prenatal interventions, are discussed.
This article is an update on fetal alcohol syndrome (FAS), its pathogenesis, potential treatments, and preventative measures. Risk factors for the development of FAS and alcohol's mechanisms as a teratogen are also discussed. With FAS being the most extreme type of fetal alcohol spectrum disorder, knowledge of this condition can help to tackle alcohol consumption during pregnancy. We invite the readership to gain a detailed yet simple understanding of this broad and complex topic.
•SO2 gas sensor prepared by integrating of MWCNTs/RGO with SnO2.•Low sensing response of 1.2 is obtained for bare SnO2 sensor at 220°C.•Sensing response ∼5 obtained for MWCNT-SnO2 sensor at ...60°C.•Enhanced sensing response of ∼22 observed for the RGO-SnO2 sensor at 60°C.
An attempt has been made in the present work to develop a hybrid nanocomposite sensor by exploiting the novel properties of Tin oxide (SnO2), MWCNTs (Carbon nanotubes) and reduced graphene oxide (RGO) for the efficient detection of SO2 gas. MWCNT-SnO2 and RGO-SnO2 hybrid nanocomposite sensors have been prepared by incorporating MWCNTs and RGO into SnO2 nanoparticle colloidal solution respectively by chemical route. Low sensing response of 1.2 is obtained for bare SnO2 sensor at 220°C towards 500ppm SO2 gas. However, enhanced sensing response of ∼22 has been observed for the RGO-SnO2 sensor compared to ∼5 obtained for MWCNT-SnO2 sensor at a lower operating temperature of 60°C towards the same concentration of SO2 gas. Modulation of space charge region at the interface of n-SnO2 and p-RGO on interaction with the target SO2 gas is responsible for the enhanced response.
•NiO thin film-based label-free electrochemical immunosensor has been devised using rf magnetron sputtering.•A low detection limit of 0.32 pg/mL in a broad range of linearity from 1 pg/mL to 10 μg/mL ...has been achieved.•The fabricated immunoelectrode possesses high selectivity against other common interferents.•The cortisol biosensor exhibits a stability of 9 weeks.•Cortisol in actual saliva samples have been successfully assessed and validated using standard ELISA.
A non-invasive electrochemical immunosensor for detection of salivary cortisol has been proposed using RF sputtered NiO thin film as sensing platform. Cortisol, a steroid hormone, plays a vital part in administrating various physiological activities and also functions to be a stress biomarker. Thus, extremely sensitive and selective non-invasive mechanism for the detection of salivary cortisol has been focused in the present work. Covalently immobilized cortisol specific antibody on the NiO matrix has been used as the sensing platform. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) studies have been implemented to calibrate the electrode using standard cortisol solutions. The label-free immunoelectrode has been successfully devised and used to achieve detection limit as low as 0.32 pg/mL with high sensitivity in a broad range of linearity from 1 pg/mL to 10 μg/mL. It has been further assessed to detect cortisol in actual saliva samples and the results exhibit a great scope to foster the development of portable, integrated and efficient miniaturized non-invasive sensing devices for cortisol determination.
In the last three decades, a lot of scientific research has been carried out in the field of Carbon nanomaterials all over the world due to their significant electronic, optical, mechanical, chemical ...and thermal properties. The zero, one, two and three dimensional Carbon nanomaterials (i.e. fullerenes, Carbon nanotubes, Graphene, Carbon quantum dots, Carbon Nanohorns, Nanodiamonds, Carbon Nanofibres and Carbon black) have exhibited such inherent features that can be easily exploited in the development of advanced technology for sensing applications. The employment of nanomaterials within sensors has paved new way and opportunities for the detection of analytes or target molecules. Carbon nanomaterials based electrochemical biosensors have reported biocompatibility, better sensitivity, better selectivity and lower limits of detection to detect a wide range of chemical to biological molecules. In this paper, a comprehensive review has been made to cover recent developments in the field of Carbon based nanomaterials as electrochemical biosensors. The characteristic features of a variety of nanomaterials like fullerenes, Carbon nanotubes, Graphene, Carbon quantum dots, Carbon Nanohorns, Carbon Nanodiamonds, Carbon Nanofibres, Carbon black etc. have been discussed along with their synthesis methods. The recent application of all these nanomaterials as electrochemical biosensors for the detection of various biomolecules have been highlighted; the future prospects and possibilities in this field have been outlined.
PANI/SWCNT composites were prepared by electrochemical polymerisation of polyaniline onto SWCNTs and their capacitive performance was evaluated by means of cyclic voltammetry and charge–discharge ...cycling in 1
M H
2SO
4 electrolyte. The PANI/SWCNT composites single electrode showed much higher specific capacitance, specific energy and specific power than pure PANI and SWCNTs. The highest specific capacitance, specific power and specific energy values of 485
F/g, 228
W
h/kg and 2250
W/kg were observed for 73
wt.% PANI deposited onto SWCNTs. PANI/SWCNT composites also showed long cyclic stability. Based upon the variations in the surface morphologies and specific capacitance of the composite, a mechanism is proposed to explain enhancement in the capacitive characteristics. The PANI/SWCNT composites have demonstrated the potential as excellent electrode materials for application in high performance supercapacitors.
Zinc oxide (ZnO) nanostructures possessing flower-like morphology have been synthesised onto platinized silicon substrate by simple and economical hydrothermal method. The interaction of physically ...immobilized single stranded thiolated DNA (ss th-DNA) probe of N. meningitides onto the nanostructured ZnO (ZNF) matrix surface have been investigated using cyclic voltammetry (CV) and electrochemical impeadance spectroscopy (EIS). The electrochemical sensing response behaviour of the DNA bioelectrode (ss th-DNA/ZNF/Pt/Si) has been studied by both differential pulse voltammetric (DPV) as well as impedimetric techniques. The fabricated DNA biosensor can quantify wide range of the complementary target ss th-DNA in the range 5–240ngμl−1 with good linearity (R=0.98), high sensitivity (168.64μAng−1μlcm−2) and low detection limit of about 5ngμl−1. Results emphasise that the fabricated flower-like ZnO nanostructures offer a useful platform for the immobilization of DNA molecules and could be exploited for efficient detection of complementary target single stranded DNA corresponding to N. meningitides.
•DNA biosensor based on flower-like ZnO nanostructures for Meningitis detection has been reported.•ZnO nanostructures have been synthesized by very simple and economical hydrothermal method.•The fabricated DNA biosensor, insures a highly developed active surface for DNA immobilization.•Very high sensitivity, wide detection range of the target DNA along with long stability has been observed.
Substantial global effort has been devoted to curtailing the tobacco epidemic over the past two decades, especially after the adoption of the Framework Convention on Tobacco Control
by the World ...Health Organization in 2003. In 2015, in recognition of the burden resulting from tobacco use, strengthened tobacco control was included as a global development target in the 2030 Agenda for Sustainable Development
. Here we show that comprehensive tobacco control policies-including smoking bans, health warnings, advertising bans and tobacco taxes-are effective in reducing smoking prevalence; amplified positive effects are seen when these policies are implemented simultaneously within a given country. We find that if all 155 countries included in our counterfactual analysis had adopted smoking bans, health warnings and advertising bans at the strictest level and raised cigarette prices to at least 7.73 international dollars in 2009, there would have been about 100 million fewer smokers in the world in 2017. These findings highlight the urgent need for countries to move toward an accelerated implementation of a set of strong tobacco control practices, thus curbing the burden of smoking-attributable diseases and deaths.
The presence of long-period pulses in the near-fault pulse-type ground motions increases the damage potential of such ground motions, particularly for the flexible structures like bridges. It is ...necessary to carry out nonlinear analyses of structural systems for ensuring their safety in the near-source regions. This study considers the simulation of fling-step motions under the assumption that a fling-step accelerogram can be decomposed into a pulse component and a component without any pulse. Fling-step pulses are extracted from a database of 20 recorded fling-step accelerograms through smoothening via the five-point moving average method and are base-line adjusted for zero velocity and permanent displacement at the end of the pulse time-window. The velocity waveform of these pulses is modelled by a mathematical function characterized by three parameters related to amplitude, duration and location of the pulse. The amplitude and duration parameters are proposed to be estimated for an anticipated motion in terms of the closest distance of site from the fault for a given magnitude and faulting mechanism, while the location parameter is proposed to be taken same as the location of peak ground acceleration in the non-pulse component. It is shown through a numerical study that the proposed method of simulation works well provided the amplitude parameter of the pulse is chosen with care.
•Simulation of fling-step motions by addition of pulse component on non-pulse motion.•Fling-step pulses extracted from 20 records via smoothing and base-line adjustment.•Pulse velocity waveform modelled in terms of amplitude, duration and location.•Pulse amplitude and duration estimated in terms of closest distance from the fault.•Pulse location taken same as location of PGA in non-pulse component.
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