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PURPOSE OF THE RESEARCH: With online education taking centerstage in recent times, the primary objective of this study is to find out the student perception of online classes from teachers who had no past experience of online teaching, with respect to their teaching effectiveness, teaching style and pedagogy in an online classroom. This study is exploratory in nature. Using a structured questionnaire, 356 completed responses were received and analysed using the available research tools. PRINCIPLE RESULTS: The dynamics of education have changed overnight. The findings of the study indicate that pedagogy, teaching style and teaching effectiveness significantly affect student perception towards online classes by first time online teachers. MAJOR CONCLUSIONS: The role of the teachers has changed drastically and there is a need for them to prepare themselves for the new normal using the suitable pedagogical tools for creating an effective online classroom.
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Norovirus is one of the leading causes of gastroenteritis, acute vomiting, intense diarrhoea, acute pain in the stomach, high fever, headaches, and body pain. Conventional methods of detection gave us very promising results but had disadvantages such as low sensitivity, cost ineffectiveness, reduced specificity and selectivity, etc. Therefore, biosensors can be a viable alternative device which can overcome all setbacks associated with the conventional method. An electrochemical sensor based on oxidized graphitic carbon nitride (Ox-g-C3N4) modified electrochemical paper-based analytical device (ePAD) was fabricated for the detection of norovirus DNA. The synthesized Ox-g-C3N4 nanosheets were characterized by field emission scanning electron microscopy (FESEM), X-ray Diffraction (XRD), UV-Vis spectroscopy and X-Ray Photoelectron Spectroscopy. The capture probe DNA (PDNA) modified electrodes were characterized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). These two characterization techniques were also employed to find the optimal scan rate, response time and temperature of the fabricated sensor. The fabricated biosensor showed a limit of detection (LOD) of 100 fM. Furthermore, the specificity of the reported biosensor was affirmed by testing the response of capture probe DNA with oxidized graphitic carbon nitride (PDNA/Ox-g-C3N4) modified ePAD on the introduction of a non-complimentary DNA. The fabricated ePAD sensor is easy to fabricate, cost effective and specific, and requires a minimum analysis time of 5 s.
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Técnicas Biossensoriais/métodos , Grafite/química , Compostos de Nitrogênio/química , Norovirus/genética , Papel , RNA Viral/análise , Técnicas Biossensoriais/instrumentação , Sondas de DNA/química , Sondas de DNA/metabolismo , Técnicas Eletroquímicas/métodos , Eletrodos , Ácidos Nucleicos Imobilizados/química , Ácidos Nucleicos Imobilizados/metabolismo , Limite de Detecção , Azul de Metileno/química , Nanoestruturas/química , Hibridização de Ácido Nucleico , RNA Viral/metabolismoRESUMO
Advancements in health care monitoring demand a rapid, accurate and reliable early diagnosis of "Heart Attack" (acute myocardial infarction) with an objective to develop a cost-effective, rapid and label-free point of care diagnostic test kit for the detection of cardiac troponin I (cTnI) on paper-based multi-frequency impedimetric transducers. Paper based sensing platforms were developed by integrating carboxyl group functionalized multi-walled carbon nanotubes (MWCNT) with antibodies of cardiac troponin I (anti-cTnI) biomarker and was characterized using Electrochemical Impedance Spectroscopy (EIS). Various concentrations of cTnI with anti cTnI were studied as a function of impedance change. The suitability of the proposed immunosensor is demonstrated by spiking cTnI in blood serum samples. The limit of detection (LoD) and sensitivity of the proposed sensor was determined to be 0.05 ng/mL and 1.85 mΩ/ng/mL respectively, with a response time of ~1 min. The shelf life of the fabricated sensor was nearly 30 days. The rapid response, very low detection limit, and cost effectiveness offer a portable platform to detect cTnI in blood serum samples. The proposed immunosensor, therefore, offers an affordable healthcare diagnostic platform in resource limited areas.
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Imunoensaio/métodos , Miocárdio/metabolismo , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Troponina I/análise , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Biomarcadores/análise , Biomarcadores/sangue , Impedância Elétrica , Eletroquímica , Eletrodos , Humanos , Limite de Detecção , Nanotubos de Carbono/química , Troponina I/sangue , Troponina I/metabolismoRESUMO
South Asians (SAs) are at heightened risk for cardiovascular disease as compared to other ethnic groups, facing premature and more severe coronary artery disease, and decreased insulin sensitivity. This disease burden can only be partially explained by conventional risk factors, suggesting the need for a specific cardiovascular risk profile for SAs. Current research, as explored through a comprehensive literature review, suggests the existence of population specific genetic risk factors such as lipoprotein(a), as well as population specific gene modulating factors. This review catalogues the available research on cardiovascular disease and genetics, anthropometry, and pathophysiology, and cancer genetics among SAs, with a geographical focus on the U.S. A tailored risk profile will hinge upon population customized classification and treatment guidelines, informed by continued research.
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Povo Asiático/estatística & dados numéricos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Neoplasias/epidemiologia , Ásia/epidemiologia , Povo Asiático/genética , Etnicidade , Feminino , Predisposição Genética para Doença/epidemiologia , Humanos , Masculino , Neoplasias/genética , PrevalênciaRESUMO
OBJECTIVE: Hypertriglyceridemic waist (HTG-waist), an increased waist circumference (WC) with an elevated triglyceride (TG) concentration, can identify increased cardiometabolic risk in apparently healthy individuals. Since WC and BMI are highly correlated, we examined whether an HTG-BMI would be as effective as an HTG-waist in identifying cardiometabolic risk in apparently healthy South Asians. DESIGN SETTING AND PARTICIPANTS: In this cross-sectional study, we classified South Asian women (n=1156) and men (n=1842) without diabetes mellitus as having an HTG-waist (TG ≥150 mg/dL and a WC ≥80 cm in women or ≥ 90 cm in men) and an HTG-BMI (TG ≥150 mg/dL and a BMI ≥23 kg/m²). OUTCOME MEASURES: We measured cardiometabolic risk factors, including blood pressure and fasting lipid profile, glucose, insulin, fibrinogen, and high-sensitivity C-reactive protein. RESULTS: An HTG-waist was present in 670 individuals, of whom 648 (97%) had an HTG-BMI. The cardiometabolic profile was significantly more adverse in those in whom an HTG-waist was present vs absent; and the same was true when individuals with an HTG-BMI were compared with those without. CONCLUSIONS: Essentially every individual with an HTG-waist also had an HTG-BMI. An HTG-BMI identified cardiometabolic risk as effectively as an HTG-waist in a population composed entirely of South Asians.
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Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Cintura Hipertrigliceridêmica , Adulto , Povo Asiático , Pressão Sanguínea , Proteína C-Reativa/metabolismo , California , Doenças Cardiovasculares/etnologia , Estudos Transversais , Diabetes Mellitus , Feminino , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Triglicerídeos/sangue , Circunferência da CinturaRESUMO
BACKGROUND & OBJECTIVES: Prevalence of insulin resistance and associated dyslipidaemia [high triglyceride (TG) and low high-density lipoprotein cholesterol (HDL-C) concentrations] are increased in South Asian individuals; likely contributing to their increased risk of type-2 diabetes and cardiovascular disease. The plasma concentration ratio of TG/HDL-C has been proposed as a simple way to identify apparently healthy individuals at high cardio-metabolic risk. This study was carried out to compare the cardio-metabolic risk profiles of high-risk South Asian individuals identified by an elevated TG/HDL-C ratio versus those with a diagnosis of the metabolic syndrome. METHODS: Body mass index, waist circumference, blood pressure, and fasting plasma glucose, insulin, TG, and HDL-C concentrations were determined in apparently healthy men (n=498) and women (n=526). The cardio-metabolic risk profile of "high risk" individuals identified by TG/HDL-C ratios in men (≥ 3.5) and women (≥2.5) was compared to those identified by a diagnosis of the metabolic syndrome. RESULTS: More concentrations of all cardio-metabolic risk factors were significantly higher in "high risk" groups, identified by either the TG/HDL-C ratio or a diagnosis of the metabolic syndrome. TG, HDL-C, and insulin concentrations were not significantly different in "high risk" groups identified by either criterion, whereas plasma glucose and blood pressure were higher in those with the metabolic syndrome. INTERPRETATION & CONCLUSIONS: Apparently healthy South Asian individuals at high cardio-metabolic risk can be identified using either the TG/HDL-C ratio or the metabolic syndrome criteria. The TG/HDL-C ratio may be used as a simple marker to identify such individuals.
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HDL-Colesterol/sangue , Síndrome Metabólica/sangue , Triglicerídeos/sangue , Adulto , Feminino , Humanos , Índia , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
Health coaching is an effective strategy for improving cardiovascular disease risk factors. Coaching interventions have primarily been studied in Caucasians, and the effectiveness in other ethnic groups is not known. Further, adaptation of coaching to include culturally specific components has not been studied. Our aim is to describe a culturally specific coaching program targeted at reducing cardiovascular disease risk in South Asians. Participants initially underwent comprehensive cardiovascular disease risk screening, then received individualized risk assessment and behavioral recommendations. A health coach then contacted participants regularly for one year to provide encouragement with behavior change, troubleshoot challenges, and assess adherence. In the first five years of the program, 3,180 people underwent risk assessment, 3,132 were candidates for coaching, 2,726 indicated a desire to participate in coaching, 1,359 received coaching, and 1,051 completed coaching for at least one year. Culturally specific health coaching is an appealing and feasible intervention for reducing cardiovascular disease risk in South Asians, with very low attrition. Coaching strategies for risk reduction are proven to be effective, but further longitudinal research is needed to determine whether the impact of incorporating cultural specificity improves the effectiveness. This program utilizes non-medically trained personnel as coaches and is relatively inexpensive, with potential for great cost savings in prevention of cardiovascular disease.
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Doenças Cardiovasculares/prevenção & controle , Comportamentos Relacionados com a Saúde/etnologia , Promoção da Saúde/métodos , Comportamento de Redução do Risco , Adulto , Ásia Ocidental/etnologia , California , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etnologia , Dieta , Escolaridade , Feminino , Humanos , Estilo de Vida/etnologia , Masculino , Pessoa de Meia-Idade , Atividade Motora , Medição de RiscoRESUMO
Hypothyroidism is a global concern that needs to be monitored, controlled and treated. Thyroxine is the most common biomarker for the diagnosis of hypothyroidism and a therapeutic hormonal replacement for hypothyroid patients. People suffering from hypothyroidism need to monitor their levels of thyroxine to avoid health complications. Diagnostic labs are not always easily accessible and, hence, point-of-care biosensors can become a useful alternative. Several studies have shown high sensitivity, selectivity and stability but there is no commercial point-of-care biosensing device available. This paper presents the critical aspects, including the need for thyroxine biosensors, the physicochemical properties of the thyroxine molecule, nanomaterials and bioreceptors used for sensing. The challenges and prospects of thyroxine biosensors are also discussed.
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Background South Asian individuals are at higher risk for arteriosclerotic cardiovascular disease and diabetes. The factors associated with arteriosclerotic cardiovascular disease severity and their interactions are unknown. Methods and Results This is a retrospective cohort study of the first 1162 South Asian participants enrolled in the South Asian Heart Center's AIM to Prevent Program who completed noncontrast coronary computed tomography scans. Using machine-learning algorithms, we identified and modeled the interaction of predictor variables with coronary artery calcification (CAC) severity in South Asian individuals. Anthropometric, laboratory, demographic, and lifestyle predictor variables were analyzed using continuous boosted regression trees to model the relationship with and in between predictor variables and CAC. Participants with CAC were older, predominately men, had smoking history, had personal histories of diabetes, hypertension, and hypercholesterolemia, and had family histories of coronary artery disease. Insulin, body mass index, blood pressure, fasting blood sugar, hemoglobin A1c, and waist-to-height ratio were associated with CAC but not low-density lipoprotein cholesterol or lipoprotein (a). The arteriosclerotic cardiovascular disease score failed to classify individuals. Only age, body mass index, non-high-density lipoprotein cholesterol/apolipoprotein B ratio, smoking risk, fasting blood sugar, and diastolic blood pressure were predictive, explaining 30.3% of CAC severity. A non-high-density lipoprotein cholesterol/apolipoprotein B ratio of 1.4 or less markedly increased coronary calcification. Conclusions Our findings highlight factors associated with dysmetabolism and cholesterol-depleted non-high-density lipoprotein cholesterol particles with coronary arteriosclerosis, possibly explaining the dual epidemics of diabetes and arteriosclerotic cardiovascular disease in this population. Markers of glucose dysmetabolism and the non-high-density lipoprotein cholesterol to apolipoprotein B ratio should become the focus of assessment for cardiovascular risk in South Asian individuals, with prevention strategies directed at improving glucose metabolic health.
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Calcinose , Doenças Cardiovasculares , Doença da Artéria Coronariana , Masculino , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/metabolismo , Glicemia , Estudos Retrospectivos , Colesterol , Fatores de Risco , Estudos de Coortes , Lipoproteína(a) , ApolipoproteínasRESUMO
Human Papilloma Virus 16 (HPV 16) is the well-known causative species responsible for triggering cervical cancer. When left undiagnosed and untreated, this disease leads to life-threatening events among the female populace, especially in developing nations where healthcare resources are already being stretched to their limits. Considering various drawbacks of conventional techniques for diagnosing this highly malignant cancer, it becomes imperative to develop miniaturized biosensing platforms which can aid in early detection of cervical cancer for enhanced patient outcomes. The current study reports on the development of an electrochemical biosensor based on reduced graphene oxide (rGO)/DNA hybrid modified flexible carbon screen-printed electrode (CSPE) for the detection of HPV 16. The carbon-coated SPEs were initially coated with rGO followed by probe DNA (PDNA) immobilization. The nanostructure characterization was performed using UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and X-ray diffraction (XRD) techniques. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were employed to study the electrochemical characterization of the nano-biohybrid sensor surface. The optimization studies and analytical performance were assessed using differential pulse voltammetry (DPV), eventually exhibiting a limit of detection (LoD) ~2 pM. The developed sensor was found to be selective solely to HPV 16 target DNA and exhibited a shelf life of 1 month. The performance of the developed flexible sensor further exhibited a promising response in spiked serum samples, which validates its application in future point-of-care scenarios.
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Anisotropic gold nanostructures have fascinated with their exceptional electronic properties, henceforth exploited for the fabrication of electrochemical sensors. However, their synthesis approaches are tedious and often require a growth template. Modern lifestyle has caused an upsurge in the risk of heart attack and requires urgent medical attention. Cardiac troponin I can serve as a biomarker in identification of suspected myocardial infection (heart attack). Hence the present work demonstrates the fabrication of a sensing platform developed by assimilating anisotropic gold nanoclusters (AuNCs) with anti cTnI antibody (acTnI) for the detection of cardiac troponin I (cTnI). The uniqueness and ease of synthesis by a template-free approach provides an extra edge for the fabrication of AuNC coated electrodes. The template-free growth of anisotropic AuNCs onto the indium tin oxide (ITO) glass substrates offers high sensitivity (2.2 × 10-4 A ng-1 mL cm-2) to the developed sensor. The immunosensor was validated by spiking different concentrations of cTnI in artificial serum with negligible interference under optimized conditions. The sensor shows a wide range of detection from 0.06-100 ng/mL with an ultralow detection limit. Thus, it suggests that the template-free immunosensor can potentially be used to screen the traces of cTnI present in blood serum samples, and the AuNCs based platform holds great promise as a transduction matrix, hence it can be exploited for broader sensing applications.
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Técnicas Biossensoriais , Nanopartículas Metálicas , Infarto do Miocárdio , Humanos , Troponina I , Ouro/química , Imunoensaio , Infarto do Miocárdio/diagnóstico , Eletrodos , Técnicas Eletroquímicas , Limite de Detecção , Nanopartículas Metálicas/químicaRESUMO
This study systematically reviews and characterizes the existing literature on transferrin/transferrin receptor-mediated drug delivery. Transferrin is an iron-binding protein. It can be used as a ligand to deliver various proteins, genes, ions, and drugs to the target site via transferrin receptors for therapeutic or diagnostic purposes via transferrin receptors. This study is based on a cross-sectional bibliometric analysis of 583 papers limited to the subject areas of pharmacology, toxicology, and pharmaceutics as extracted from the Scopus database in mid-September 2022. The data were analyzed, and we carried out a performance analysis and science mapping. There was a significant increase in research from 2018 onward. The countries that contributed the most were the USA and China, and most of the existing research was found to be from single-country publications. Research studies on transferrin/transferrin receptor-mediated drug delivery focus on drug delivery across the blood-brain barrier in the form of nanoparticles. The thematic analysis revealed four themes: transferrin/transferrin receptor-mediated drug delivery to the brain, cancer cells, gene therapy, nanoparticles, and liposomes as drug delivery systems. This study is relevant to academics, practitioners, and decision makers interested in targeted and site-specific drug delivery.
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The extensive use of organophosphates (OPs) pollutes the environment, leading to serious health hazards for human beings. The current need is to fabricate a sensing platform that will be sensitive and selective towards the detection of OPs at trace levels in the nM to fM range. With this discussed in the present report, an ultra-sensitive immunosensing platform is developed using digestive-ripened copper oxide quantum dots grafted on a gold microelectrode (Au-µE) for the impedimetric detection of parathion (PT). The copper oxide quantum dots utilized in this study were of ultra-small size with a radius of approximately 2 to 3 nm and were monodispersed with readily available functional groups for the potential immobilization of antibody parathion (Anti-PT). The miniaturization is achieved by the utilization of Au-µE and the microfluidic platform utilized has the sample holding capacity of about 2 to 10 µL. The developed immunosensor provided a wide linear range of detection from 1 µM to 1 fM. The lower Limit of Detection (LoD) for the developed sensing platform was calculated to be 0.69 fM, with the sensitivity calculated to be 0.14 kΩ/nM/mm2. The stability of the sensor was found to be ~40 days with good selectivity. The developed sensor has the potential to integrate with a portable device for field applications.
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Amoxicillin (AMX) is a widely used antibiotic, which induces harmful effects to nature via bioaccumulation and persistence in the environment if discharged untreated into water bodies. In the current study, a novel bionanocomposite, bismuth oxyiodide-chitosan (BiOI-Ch), was synthesized by a facile precipitation method and its amoxicillin (AMX) adsorption capacity in the presence of ultrasonic waves has been explored. Multiple batch experiments were performed to achieve the optimum operational parameters for maximum adsorption of AMX and the obtained results were as follows: pH 3, 80 mg g-1 AMX concentration, 1.7 g L-1 adsorbent dose, temperature 298 K and ultrasonication time 20 min. Composite removed approximately 90% AMX from the solution under optimized conditions, while the maximal adsorption capacity was determined to be 81.01 mg g-1. BiOI-Ch exhibited superior adsorption capacity as compared to pure BiOI (33.78 mg g-1). To understand the dynamics of reaction, several kinetic and isotherm models were also examined. The adsorption process obeyed pseudo-second-order kinetic model (R2 = 0.98) and was well fitted to Freundlich isotherm (R2 = 0.99). The addition of biowaste chitosan to non-toxic bismuth-based nanoparticles coupled with ultrasonication led to enhanced functional groups as well as surface area of the nanocomposite resulting in superior adsorption capacity, fast adsorption kinetics and improved mass transfer for the removal of AMX molecules. Thus, this study demonstrates the synergistic effect of ultrasonication in improved performance of novel BiOI-Ch for potential application in the elimination of persistent and detrimental pollutants from industrial effluent after necessary optimization for large-scale operation.
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Quitosana , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Quitosana/química , Bismuto , Purificação da Água/métodos , Amoxicilina/química , Poluentes Químicos da Água/análise , Nanocompostos/química , Cinética , Termodinâmica , Água , Ondas Ultrassônicas , Concentração de Íons de HidrogênioRESUMO
In this study, we report on a novel aptasensor based on an electrochemical paper-based analytical device (ePAD) that employs a tungsten disulfide (WS2)/aptamer hybrid for the detection of Listeria monocytogenes. Listeria is a well-known causative pathogen for foodborne diseases. The proposed aptasensor signifies many lucrative features which include simple, cost-effective, reliable, and disposable. Furthermore, the use of an aptamer added more advantageous features in the biosensor. The morphological, optical, elemental composition, and phase properties of the synthesized tungsten disulfide (WS2) nanostructures were characterized by field-emission scanning electron microscopy (FESEM), RAMAN spectroscopy, photoluminescence (PL), and X-ray diffraction (XRD), while electrochemical impedance spectroscopy was performed to corroborate the immobilization of aptamer and to assess the L. monocytogenes sensing performance. The limit of detection (LoD) and limit of quantification (LoQ) of the aptasensor was found to be 10 and 4.5 CFU/mL, respectively, within a linear range of 101-108 CFU/mL. The proposed sensor was found to be selective solely towards Listeria monocytogenes in the presence of various bacterial species such as Escherichia coli and Bacillus subtilis. Validation of the aptasensor operation was also evaluated in real samples by spiking them with fixed concentrations (101, 103, and 105) of Listeria monocytogenes, thereby, paving the way for its potential in a point-of-care scenario.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Listeria monocytogenes , Nanoestruturas , Sulfetos/química , Compostos de Tungstênio/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Escherichia coli/química , Limite de DetecçãoRESUMO
Vertically aligned multi-walled carbon nanotubes (CNTs) were grown on p-type silicon wafer using thermal chemical vapor deposition process and subsequently treated with oxygen plasma for oxidation. It was observed that the electron field emission (EFE) characteristics are enhanced. It showed that the turn-on electric field (E(TOE)) of CNTs decreased from 0.67 (untreated) to 0.26 V/microm (oxygen treated). Raman spectra showed that the numbers of defects are increased, which are generated by oxygen-treatment, and absorbed molecules on the CNTs are responsible for the enhancement of EFE. Scanning electron microscopy and Transmission electron microscopy images were used to identify the quality and physical changes of the nanotube morphology and surfaces; revealing the evidence of enhancement in the field emission properties after oxygen-plasma treatment.
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Nanotubos de Carbono , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução , Análise Espectral RamanRESUMO
The occurrence of heavy metal ions in food chain is appearing to be a major problem for mankind. The traces of heavy metals, especially Pb(II) ions present in water bodies remains undetected, untreated, and it remains in the food cycle causing serious health hazards for human and livestock. The consumption of Pb(II) ions may lead to serious medical complications including multiple organ failure which can be fatal. The conventional methods of heavy metal detection are costly, time-consuming and require laboratory space. There is an immediate need to develop a cost-effective and portable sensing system which can easily be used by the common man without any technical knowhow. A portable resistive device with miniaturized electronics is developed with microfluidic well and α-MnO2 /GQD nanocomposites as a sensing material for the sensitive detection of Pb(II). α-MnO2 /GQD nanocomposites which can be easily integrated with the miniaturized electronics for real-time on-field applications. The proposed sensor exhibited a tremendous potential to be integrated with conventional water purification appliances (household and commercial) to give an indication of safety index for the drinking water. The developed portable sensor required low sample volume (200 µL) and was assessed within the Pb(II) concentration range of 0.001 nM to 1 uM. The Limit of Detection (LoD) and sensitivity was calculated to be 0.81 nM and 1.05 kΩ/nM/mm2 , and was validated with the commercial impedance analyser. The shelf-life of the portable sensor was found to be â¼45 days.
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Chumbo , Nanocompostos , Humanos , Compostos de Manganês , Óxidos , ÁguaRESUMO
Nanotubes of carbon are allotropic form of carbon material that rolled to form a cylindrical structure that may be singlewalled carbon nanotubes (SWCNTs) and multiwalled carbon nanotubes (MWCNTs) depending upon the number of carbon layers. These carbon nanotubes have exhibited characteristics properties such as âelectrical, optical, thermal and mechanical. Carbon nanotubes can be employed for immobilization matrix for biomolecules such as an enzyme, nucleic acid, etc. Enzymes can be immobilized onto carbon nanotubes via absorption or covalent bonding. Various enzymatic based biosensors are also developed for the detection of various analytes. Present chapter mainly emphasizes characteristics of carbon nanotubes, their preparation methods, purification and exploitation of CNTs as an immobilization matrix for theranostic applications.
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Técnicas Biossensoriais/métodos , Nanomedicina/métodos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Animais , Enzimas Imobilizadas/química , HumanosRESUMO
We report the development of an ultrasensitive electrochemical sensor using polyaniline (PANi) and carboxyl functionalized multi-walled carbon nanotubes (fMWCNT) for the detection of organophosphates (OPs) in real samples. The sensor was tested in the linear concentration range of 10 ng/L to 120 ng/L. The limit of detection (LoD) was found to be 8.8 ng/L with sensitivity 0.41 mA/ng/L/cm2 for chlorpyrifos (CPF); and 10.2 ng/L with sensitivity 0.58 mA/ng/L/cm2 for methyl parathion (MP). The vegetable samples (cucumber) were also tested. The average % recovery for CPF and MP were found to be 98.05% and 96.63% respectively. The developed sensor showed stability for a period of 30 days. The interference of the sensor was studied with heavy metals (cadmium (Cd), chromium (Cr), lead (Pb), arsenic (As)) which was found to be < 10%. The developed sensor will play a major role in real-time monitoring of food products, leading to food safety.
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Vaccines have contributed substantially to decreasing the morbidity and mortality rates of many infectious diseases worldwide. Despite this achievement, an increasing number of parents have adopted hesitant behaviours towards vaccines, delaying or even refusing their administration to children. This has implications not only on individuals but also society in the form of outbreaks for e.g. measles, chicken pox, hepatitis A, etc. A review of the literature was conducted to identify the determinants of vaccine hesitancy (VH) as well as vaccine confidence and link them to challenges and opportunities associated with vaccination in India, safety concerns, doubts about the need for vaccines against uncommon diseases and suspicions towards new vaccines were identified as major vaccine-specific factors of VH. Lack of awareness and limited access to vaccination sites were often reported by hesitant parents. Lastly, socio-economic level, educational level and cultural specificities were contextual factors of VH in India. Controversies and rumours around some vaccines (e.g., human papillomavirus) have profoundly impacted the perception of the risks and benefits of vaccination. Challenges posed by traditions and cultural behaviours, geographical specificities, socio-demographic disparities, the healthcare system and vaccine-specific features are highlighted, and opportunities to improve confidence are identified. To overcome VH and promote vaccination, emphasis should be on improving communication, educating the new generation and creating awareness among the society. Tailoring immunisation programmes as per the needs of specific geographical areas or communities is also important to improve vaccine confidence. Fig. 1 Plain language summary.