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Fulltext Tuning the Magnetism in Boron-Doped Strontium Titanate

Zeng H, Wu M, Wang HQ, Zheng JC, Kang J

Materials (Basel), 2020 Dec 12;13(24).
PMID: 33322841 DOI: 10.3390/ma13245686

The magnetic and electronic properties of boron-doped SrTiO3 have been studied by first-principles calculations. We found that the magnetic ground states of B-doped SrTiO3 strongly depended on the dopant-dopant separation distance. As the dopant-dopant distance varied, the magnetic ground states of B-doped SrTiO3 can have nonmagnetic, ferromagnetic or antiferromagnetic alignment. The structure with the smallest dopant-dopant separation exhibited the lowest total energy among all configurations considered and was characterized by dimer pairs due to strong attraction. Ferromagnetic coupling was observed to be stronger when the two adjacent B atoms aligned linearly along the B-Ti-B axis, which could be associated with their local bonding structures. Therefore, the symmetry of the local structure made an important contribution to the generation of a magnetic moment. Our study also demonstrated that the O-Ti-O unit was easier than the Ti-B-Ti unit to deform. The electronic properties of boron-doped SrTiO3 tended to show semiconducting or insulating features when the dopant-dopant distance was less than 5 Å, which changed to metallic properties when the dopant-dopant distance was beyond 5 Å. Our calculated results indicated that it is possible to manipulate the magnetism and band gap via different dopant-dopant separations.

Matched MeSH terms: Electronics
Fulltext Structural and Optical Characteristics of PVA:C-Dot Composites: Tuning the Absorption of Ultra Violet (UV) Region

Aziz SB, Hassan AQ, Mohammed SJ, Karim WO, Kadir MFZ, Tajuddin HA, et al.

Nanomaterials (Basel), 2019 Feb 06;9(2).
PMID: 30736346 DOI: 10.3390/nano9020216

: In this work the influence of carbon nano-dots (CNDs) on absorption of ultra violet (UV) spectra in hybrid PVA based composites was studied. The FTIR results reveal the complex formation between PVA and CNDs. The shifting was observed in XRD spectrum of PVA:CNDs composites compared to pure PVA. The Debye-Scherrer formula was used to calculate the crystallite size of CNDs and crystalline phases of pure PVA and PVA:CNDs composites. The FESEM images emphasized the presence and dispersion of C-dots on the surface of the composite samples. From the images, a strong and clear absorption was noticed in the spectra. The strong absorption that appeared peaks at 280 nm and 430 nm can be ascribed to the n-π* and π-π* transitions, respectively. The absorption edge shifted to lower photon energy sides with increasing CNDs. The luminescence behavior of PVA:CNDs composite was confirmed using digital and photo luminescence (PL) measurements. The optical dielectric constant which is related to the density of states was studied and the optical band gap was characterized accurately using optical dielectric loss parameter. The Taucs model was used to determine the type of electronic transition in the samples.

Matched MeSH terms: Electronics
Fulltext Development of Smart Shoes Using Piezoelectric Material

Affa Rozana Abdul Rashid, Nur Insyierah Md Sarif, Khadijah Ismail

Malaysian Journal of Science, Health & Technology, 2021;7(1):49-55.
MyJurnal

The consumption of low-power electronic devices has increased rapidly, where almost all applications use power electronic devices. Due to the increase in portable electronic devices’ energy consumption, the piezoelectric material is proposed as one of the alternatives of the significant alternative energy harvesters. This study aims to create a prototype of “Smart Shoes” that can generate electricity using three different designs embedded by piezoelectric materials: ceramic, polymer, and a combination of both piezoelectric materials. The basic principle for smart shoes’ prototype is based on the pressure produced from piezoelectric material converted from mechanical energy into electrical energy. The piezoelectric material was placed into the shoes’ sole, and the energy produced due to the pressure from walking, jogging, and jumping was measured. The energy generated was stored in a capacitor as piezoelectric material produced a small scale of energy harvesting. The highest energy generated was produced by ceramic piezoelectric material under jumping activity, which was 1.804 mJ. Polymer piezoelectric material produced very minimal energy, which was 55.618 mJ. The combination of both piezoelectric materials produced energy, which was 1.805 mJ from jumping activity.

Matched MeSH terms: Electronics
Fulltext Infusion phlebitis assessment method used in paediatric setting: a systematic review of literature

Li Tsu Chong, Deena Clare Thomas, Renie Martha Joanes, Rose A Nain

Malaysian Journal of Medicine and Health Sciences, 2020;16(105):62-0.
MyJurnal

Introduction: Phlebitis may localise to the insertion site or travel along the vein. The risk of phlebitis is higher in children as they have thin and weak blood vessels and move continuously due to the pain associated with insertion. Therefore, regular assessment of the risk of developing phlebitis is crucial. This review aimed to identify infusion phlebitis assessment tool used in the paediatric setting. Methods: Electronic databases used were Scopus, ProQuest, ScienceDirect, and Google Scholar. A total of ten studies which assess the development of infusion phlebitis on hos- pitalised children included in this reviewed. Study findings were discussed and concluded with a recommendation for clinical practice and future studies. Results: Phlebitis development rate was the primary outcome measures in ten studies. Of ten studies, six provided no actual definition of phlebitis. Eight reported phlebitis incidence and/or severity, eight used a scale and two used a definition alone in assessing the development of phlebitis. This review identified five different phlebitis assessment scales. Conclusion: Although there are applicable phlebitis scales can be used for paediatric setting, Limited studies have been conducted on infusion phlebitis assessment method in chil- dren. Therefore, it is suggested that more studies and vigorous test needed to identify applicable assessment tools in paediatric setting.

Matched MeSH terms: Electronics
Fulltext Investigations on physical characteristics of three-dimensional coil structure for MEMS magnetometer

N. Sulaiman, B. Y. Majlis

ASM Science Journal, 2013;7(1):27-36.
MyJurnal

Measurement of low magnetic field has played an important role in many electronics applications such as navigation, military, non-destructive test, traffic detection as well as medical diagnosis and treatment. The presence of magnetic field, particularly its strength and direction, can be measured using magnetometer. There are many types of magnetometers being investigated through the years and one of the prominent types is fluxgate magnetometer. The main components of fluxgate magnetometer consisting of driving coils, sensing coils and magnetic core are developed by MEMS silicon processing technology. In this paper, an investigation on physical characteristics of the three-dimensional coil structure for a micro-scaled fluxgate magnetometer is presented. The physical characteristics such as width of the coil, distance between successive coils, and gap between the top and bottom coils which would influence the magnetic energy in magnetometer is discussed. In this work, finite-element method simulations to investigate the physical characteristics of the sensing coils were carried out, where the parameter of interest is the coils’ inductance as well as the magnetic flux density. Based on the simulation results, the varying of physical characteristics of the coils had its effects particularly in coil inductance, magnetic flux density, and magnetic energy. It could also be seen that the simulated results agreed with the theoretical aspects of magnetism in a coil. From the investigations, suitable coil dimensions were proposed.

Matched MeSH terms: Electronics
Fulltext Left-handed metamaterial bandpass filter for GPS, Earth Exploration-Satellite and WiMAX frequency sensing applications

Alam MJ, Ahamed E, Faruque MRI, Islam MT, Tamim AM

PLoS One, 2019;14(11):e0224478.
PMID: 31714917 DOI: 10.1371/journal.pone.0224478

Interferences and accuracy problem are one of the most talked issues in today's world for sensor technology. To deal with this contention, a microstrip framework consisting of a dual mode double negative (DNG) metamaterial based bandpass filter is presented in this article. To obtain the ultimate noise reduction bandpass filter, the proposed structure has to go through a series of development process, where the characteristics of the structure are tested to the limit. This filter is built on Rogers RT-5880 substrate with a 50Ω microstrip line. To pursue the elementary mode of resonant frequency, the ground layer of the structure is kept partially filled and a gradual analysis is executed on the prospective metamaterial (resonator) unit cell. Depending on the developed unit cell, the filter is constructed and fabricated to verify the concept, concentrating on GPS (1.55GHz), Earth Exploration-Satellite (2.70GHz) and WiMAX (3.60GHz) bands of frequencies. Moreover, the structure is investigated using Nicolson-Ross-Weir (NRW) approach to justify the metamaterial characteristics, and also tested on S-parameters, current distribution, electric and magnetic fields and quality factor. Having a propitious architecture and DNG characteristics, the proposed structure is suitable for bandpass filter for GPS, Earth Exploration-Satellite and WiMAX frequency sensing applications.

Matched MeSH terms: Electronics
E-waste recycling intention paradigm of small and medium electronics store managers in Bangladesh: An S-O-R perspective

Mahmud I, Sultana S, Rahman A, Ramayah T, Cheng Ling T

Waste Manag Res, 2020 Dec;38(12):1438-1449.
PMID: 32364437 DOI: 10.1177/0734242X20914753

Each year Bangladesh produces around 400,000 metric tonnes of e-waste. E-waste accumulation is expected to increase by 20% annually. In order to facilitate e-waste recycling, it is crucial to identify the factors. In this study, building on the stimulus-organism-response framework, we develop a research model to explore the effect of information publicity, ascription of responsibility and convenience of recycling on the recycling attitude, subjective norm, personal norm and perceived behaviour control which lead to recycling intention. Data were gathered from 127 small and medium electronics store managers. The structural equation modelling technique was used to test the paths. The result suggests a significant influence of the element of stimulus (S) on the element of organism (O). The relationship between the element of organism (O) and the element of response (R) is partial. This paper contributes to the body of work dedicated to helping us better understand the recycling behaviour from the stimulus-organism-response perspective. From the viewpoint of practice, this research sheds light on some of the challenges that the implementer might face when making strategy and policy for e-waste management in Bangladesh.

Matched MeSH terms: Electronics
Fulltext Electronic informed consent criteria for research ethics review: a scoping review

Yusof MYPM, Teo CH, Ng CJ

BMC Med Ethics, 2022 Nov 21;23(1):117.
PMID: 36414962 DOI: 10.1186/s12910-022-00849-x

BACKGROUND: The research shows a growing trend in using an electronic platform to supplement or replace traditional paper-based informed consent processes. Instead of the traditionally written informed consent document, electronic informed consent (eConsent) may be used to assess the research subject's comprehension of the information presented. By doing so, respect for persons as one of the research ethical principles can be upheld. Furthermore, these electronic methods may reduce potential airborne infection exposures, particularly during the pandemic, thereby adhering to the beneficence and nonmaleficence principle. This scoping review aims to identify the ethics related criteria that have been included in electronic informed consent processes and to synthesize and map these criteria to research ethics principles, in order to identify the gaps, if any, in current electronic informed consent processes.
METHODS: The search was performed based on internet search and three main databases: PubMed, SCOPUS and EBSCO. PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and Explanation guideline was used to report this work.
RESULTS: Of 34 studies that met the inclusion criteria, 242 essential original constructs were collated, and 7 concepts were derived. Digital content showed the highest percentage of collated original constructs (27%, n = 65) followed by accessibility (24%, n = 56), comprehension engagement (18%, n = 43), autonomy (14%, n = 34), confidentiality (11%, n = 25), language (5%, n = 13), and parental consent (1%, n = 2). Twenty-five new items were synthesized for eConsent criteria which may provide guidance for ethical review of research involving eConsent.
CONCLUSION: The current study adds significant value to the corpus of knowledge in research ethics by providing ethical criteria on electronic informed consent based on evidence-based data. The new synthesized items in the criteria can be readily used as an initial guide by the IRB/REC members during a review process on electronic informed consent and useful to the future preparation of a checklist.

Matched MeSH terms: Electronics
Fulltext Soldering Characteristics and Mechanical Properties of Sn-1.0Ag-0.5Cu Solder with Minor Aluminum Addition

Leong YM, Haseeb ASMA

Materials (Basel), 2016 Jun 28;9(7).
PMID: 28773645 DOI: 10.3390/ma9070522

Driven by the trends towards miniaturization in lead free electronic products, researchers are putting immense efforts to improve the properties and reliabilities of Sn based solders. Recently, much interest has been shown on low silver (Ag) content solder SAC105 (Sn-1.0Ag-0.5Cu) because of economic reasons and improvement of impact resistance as compared to SAC305 (Sn-3.0Ag-0.5Cu. The present work investigates the effect of minor aluminum (Al) addition (0.1-0.5 wt.%) to SAC105 on the interfacial structure between solder and copper substrate during reflow. The addition of minor Al promoted formation of small, equiaxed Cu-Al particle, which are identified as Cu₃Al₂. Cu₃Al₂ resided at the near surface/edges of the solder and exhibited higher hardness and modulus. Results show that the minor addition of Al does not alter the morphology of the interfacial intermetallic compounds, but they substantially suppress the growth of the interfacial Cu₆Sn₅ intermetallic compound (IMC) after reflow. During isothermal aging, minor alloying Al has reduced the thickness of interfacial Cu₆Sn₅ IMC but has no significant effect on the thickness of Cu₃Sn. It is suggested that of atoms of Al exert their influence by hindering the flow of reacting species at the interface.

Matched MeSH terms: Electronics
Fulltext Free-Radical Photopolymerization of Acrylonitrile Grafted onto Epoxidized Natural Rubber

Whba R, Su'ait MS, Tian Khoon L, Ibrahim S, Mohamed NS, Ahmad A

Polymers (Basel), 2021 Feb 23;13(4).
PMID: 33672185 DOI: 10.3390/polym13040660

The exploitation of epoxidized natural rubber (ENR) in electrochemical applications is approaching its limits because of its poor thermo-mechanical properties. These properties could be improved by chemical and/or physical modification, including grafting and/or crosslinking techniques. In this work, acrylonitrile (ACN) has been successfully grafted onto ENR- 25 by a radical photopolymerization technique. The effect of (ACN to ENR) mole ratios on chemical structure and interaction, thermo-mechanical behaviour and that related to the viscoelastic properties of the polymer was investigated. The existence of the -C≡N functional group at the end-product of ACN-g-ENR is confirmed by infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses. An enhanced grafting efficiency (~57%) was obtained after ACN was grafted onto the isoprene unit of ENR- 25 and showing a significant improvement in thermal stability and dielectric properties. The viscoelastic behaviour of the sample analysis showed an increase of storage modulus up to 150 × 103 MPa and the temperature of glass transition (Tg) was between -40 and 10 °C. The loss modulus, relaxation process, and tan delta were also described. Overall, the ACN-g-ENR shows a distinctive improvement in characteristics compared to ENR and can be widely used in many applications where natural rubber is used but improved thermal and mechanical properties are required. Likewise, it may also be used in electronic applications, for example, as a polymer electrolyte in batteries or supercapacitor.

Matched MeSH terms: Electronics
Fulltext The Role of Zinc Chloride in Enhancing Mechanical, Thermal and Electrical Performance of Ethylene Vinyl Acetate/Carbonized Wood Fiber Conductive Composite

Mohd Pisal MH, Osman AF, Jin TS, Rahman RA, Alrashdi AA, Masa A

Polymers (Basel), 2021 Feb 17;13(4).
PMID: 33671304 DOI: 10.3390/polym13040600

Carbonized natural filler can offer the production of low cost composites with an eco-friendliness value. The evolving field of electronics encourages the exploration of more functions and potential for carbonized natural filler, such as by modifying its surface chemistry. In this work, we have performed surface modification on carbonized wood fiber (CWF) prior to it being used as filler in the ethylene vinyl acetate (EVA) composite system. Zinc chloride (ZnCl2) with various contents (2 to 8 wt%) was used to surface modify the CWF and the effects of ZnCl2 composition on the surface morphology and chemistry of the CWF filler were investigated. Furthermore, the absorptive, mechanical, thermal, and electrical properties of the EVA composites containing CWF-ZnCl2 were also analyzed. SEM images indicated changes in the morphology of the CWF while FTIR analysis proved the presence of ZnCl2 functional groups in the CWF. EVA composites incorporating the CWF-ZnCl2 showed superior mechanical, thermal and electrical properties compared to the ones containing the CWF. The optimum content of ZnCl2 was found to be 6 wt%. Surface modification raised the electrical conductivity of the EVA/CWF composite through the development of conductive deposits in the porous structure of the CWF as a channel for ionic and electronic transfer between the CWF and EVA matrix.

Matched MeSH terms: Electronics
Fulltext Teaching listening skills in the 21st century

Wan Faizatul Azirah Ismayatim, Nur Dalila Mohamad Nazri, Ramiaida Darmi, Nursyuhada’ Ab Wahab, Nur Adibah Zamri, Haliza Harun, et al.

Jurnal Inovasi Malaysia, 2020;4(1):173-192.
MyJurnal

This paper presents an innovation of a revolutionized self-directed English learning module entitled My Electronic Visual and Audio (MyEVO), which is designed and developed to assist language learners to conveniently acquire the required listening skills through the combination of current and state-of-the-art technology - Augmented Reality (AR) and mobile applications. Using Video Media method introduced by Gruba (1997, 2004), all listening practices in this module are based on video recording. Feedbacks gained from the users of the module indicate that learners are very excited and happy to use technology assisted module in acquiring listening skills compared to the traditional module. Educators also believe that this module cater the needs of the 21st century learners and is suitable to be used inside the classroom or as a self-directed learning module. Another key feature of this smart module highlighted by the educators is the ability of the mobile application that allows learners to engage with the e-global community known as ‘MyEVO community, where all users can share their answers and exchange opinions regarding the given questions. In addition, listening activities that were designed in this module also cover the Higher Order Thinking Skills (HOTS) needed in learning. Educators also agreed that this interactive feature does not only encourage the learners to be active in their learning but it also helps to reduce their anxiety, learning process becomes more interesting and helps to aid their understanding of the topics covered.

Matched MeSH terms: Electronics
Dual-response quadratic model for optimisation of electricity generation and chlorophenol degradation by electro-degradative Bacillus subtilis in microbial fuel cell system

Hassan H, Jin B, Dai S

Environ Technol, 2021 Apr 01.
PMID: 33749543 DOI: 10.1080/09593330.2021.1907451

The interactions within microbial, chemical and electronic elements in microbial fuel cell (MFC) system can be crucial for its bio-electrochemical activities and overall performance. Therefore, this study explored polynomial models by response surface methodology (RSM) to better understand interactions among anode pH, cathode pH and inoculum size for optimising MFC system for generation of electricity and degradation of 2,4-dichlorophenol. A statistical central composite design by RSM was used to develop the quadratic model designs. The optimised parameters were determined and evaluated by statistical results and the best MFC systematic outcomes in terms of current generation and chlorophenol degradation. Statistical results revealed that the optimum current density of 106 mA/m2 could be achieved at anode pH 7.5, cathode pH 6.3-6.6 and 21-28% for inoculum size. Anode-cathode pHs interaction was found to positively influence the current generation through extracellular electron transfer mechanism. The phenolic degradation was found to have lower response using these three parameter interactions. Only inoculum size-cathode pH interaction appeared to be significant where the optimum predicted phenolic degradation could be attained at pH 7.6 for cathode pH and 29.6% for inoculum size.

Matched MeSH terms: Electronics
Fulltext Does quality stimulate customer satisfaction where perceived value mediates and the usage of social media moderates?

Uzir MUH, Jerin I, Al Halbusi H, Hamid ABA, Latiff ASA

Heliyon, 2020 Dec;6(12):e05710.
PMID: 33367128 DOI: 10.1016/j.heliyon.2020.e05710

Customer is considered as the king in the world of business. The issue of customer satisfaction in electronics home appliances has received greater attention from academics and practitioners. In other words, customer satisfaction is a vital consideration in marketing. With the development of technology, new and innovative electronic home appliances are available in the market. Customers purchase and use the costly electronic home appliances where the satisfaction issue is an important concern. In Bangladesh, working families find the electronic home appliance very necessary. Companies offer state-of- the-art appliances for customers' household works. Therefore, the study intends to investigate the effect of product quality (PQ), quality of service (SQ) and perceived value on customer satisfaction (CS). In addition, this study also seeks this relationship shaped by customer's perceived value (CPV) as a key mechanism and interacted by social media usage. A total of 300 households were selected on a judgmental basis from Dhaka city in Bangladesh using a structured questionnaire. Collected data were CB-SEM (AMOS-v24) and SPSS. The findings showed PQ and SQ have positive effects on CS; SQ affects, but PQ does not affect CPV. CPV has a mixing mediating effect on SQ and CS relationship and PQ and CS relationship. Importantly, the positive impact of PQ, SQ and CPV is greater on customers who exhibit higher social media use. The conceptual framework was buttressed by EDT theory. The study contributed to contextual and theoretical knowledge in regards to home appliances. The practicing managers can collect an insight of customer satisfaction for their business.

Matched MeSH terms: Electronics
Fulltext Electrical transportation mechanisms of molybdenum disulfide flakes-graphene quantum dots heterostructure embedded in polyvinylidene fluoride polymer

Ooi PC, Mohammad Haniff MAS, Mohd Razip Wee MF, Goh BT, Dee CF, Mohamed MA, et al.

Sci Rep, 2019 May 01;9(1):6761.
PMID: 31043694 DOI: 10.1038/s41598-019-43279-3

In the interest of the trend towards miniaturization of electronic gadgets, this study demonstrates a high-density data storage device with a very simple three-stacking layer consisting of only one charge trapping layer. A simple solution-processed technique has been used to fabricate the tristable non-volatile memory. The three-stacking layer was constructed in between two metals to form a two-terminal metal-insulator-metal structure. The fabricated device showed a large multilevel memory hysteresis window with a measured ON/OFF current ratio of 107 that might be attributed to the high charge trapped in molybdenum disulphide (MoS2) flakes-graphene quantum dots (GQDs) heterostructure. Transmission electron microscopy was performed to examine the orientation of MoS2-GQD and mixture dispersion preparation method. The obtained electrical data was used further to speculate the possible transport mechanisms through the fabricated device by a curve fitting technique. Also, endurance cycle and retention tests were performed at room temperature to investigate the stability of the device.

Matched MeSH terms: Electronics
Simulated electronic health documentation: A cross-sectional exploration of factors influencing nursing students' intention to use

Chan KG, Pawi S, Ong MF, Kowitlawakul Y, Goy SC

Nurse Educ Pract, 2020 Oct;48:102864.
PMID: 32920369 DOI: 10.1016/j.nepr.2020.102864

The aim of this study was to investigate factors influencing nursing students' intention to use a simulated web-application 'Integrated Nursing Education System' for practicing electronic health documentation. The cross-sectional study was conducted at a Malaysian University that provides undergraduate nursing degree program. A total of 133 undergraduate nursing students in their year 2 to year 4 of the program were recruited. They had accessed the simulated web-application as part of the teaching-learning activities during the academic year 2016/2017. Technology Acceptance Model was used to guide the study. Validated questionnaires were used to measure the students' perceived ease of use, perceived usefulness, attitudes and intention to use the application. Data collection was done at the end of the semester. Data analysis was done using SPSS (19.0) and AMOS (23.0). Perceived usefulness was the most influential factor of the students' intention to use the simulated web-application. Perceived ease of use influenced their perceived usefulness significantly. Nurse educators should explain the usefulness of the simulated web-application before assigning students to access it to practice electronic health documentation. The availability of a stable internet access and IT support is important to influence students' perceived ease of use and intention to use the application.

Matched MeSH terms: Electronics
Fulltext Development and implementation of a potential coronavirus disease 2019 (COVID-19) vaccine: A systematic review and meta-analysis of vaccine clinical trials

Sathian B, Asim M, Banerjee I, Roy B, Pizarro AB, Mancha MA, et al.

Nepal J Epidemiol, 2021 Mar;11(1):959-982.
PMID: 33868742 DOI: 10.3126/nje.v11i1.36163

Background: To date, there is no comprehensive systematic review and meta-analysis to assess the suitability of COVID-19 vaccines for mass immunization. The current systematic review and meta-analysis was conducted to evaluate the safety and immunogenicity of novel COVID-19 vaccine candidates under clinical trial evaluation and present a contemporary update on the development and implementation of a potential vaccines.
Methods: For this study PubMed, MEDLINE, and Embase electronic databases were used to search for eligible studies on the interface between novel coronavirus and vaccine design until December 31, 2020.
Results: We have included fourteen non-randomized and randomized controlled phase I-III trials. Implementation of a universal vaccination program with proven safety and efficacy through robust clinical evaluation is the long-term goal for preventing COVID-19. The immunization program must be cost-effective for mass production and accessibility. Despite pioneering techniques for the fast-track development of the vaccine in the current global emergency, mass production and availability of an effective COVID-19 vaccine could take some more time.
Conclusion: Our findings suggest a revisiting of the reported solicited and unsolicited systemic adverse events for COVID-19 candidate vaccines. Hence, it is alarming to judiciously expose thousands of participants to COVID-19 candidate vaccines at Phase-3 trials that have adverse events and insufficient evidence on safety and effectiveness that necessitates further justification.

Matched MeSH terms: Electronics
Naked Eye Chemosensing of Anions by Schiff Bases

Junaid HM, Batool M, Harun FW, Akhter MS, Shabbir N

Crit Rev Anal Chem, 2020 Sep 08.
PMID: 32897731 DOI: 10.1080/10408347.2020.1806703

Spectacular color change during a chemical reaction is always fascinating. A variety of chemosensors including Schiff bases have been reported for selective as well as sensitive recognition of ions. This review explains the use of Schiff bases as color changing agents in the detection of anions. This magic of colors is attributed to change in the electronic structure of the system during reaction. Schiff base chemosensors are easy to synthesize, inexpensive and can be used for visual sensing of different ions. Development of Schiff base chemosensors is commonly based on the interactions between polar groups of Schiff bases and ionic species and the process of charge transfer, electron transfer and hydrogen bonding between Schiff bases and ionic species cause the color of the resultant to be changed. Therefore, designing of simple Schiff base chemosensors which are capable of selective sensing of different anions has attracted considerable interest. In particular, naked eye sensing through color change is important and useful since it allows sensing of ions through color changes without using any instrumental technique.HighlightsNaked eye sensors are of much interest these days due to their visual detection properties rather employing complex instrumentation.Optical sensors are sensitive, selective, cost effective and robust.The magic of color change is fascinating factor in detection by these sensors.The color change may be attributed by interaction between anion and Schiff base by different mechanism i.e. electron transfer, charge transfer, hydrogen bonding, ICT etc.LOD data is an evidence of their great efficiency.

Matched MeSH terms: Electronics
Preadmission use of inhaled corticosteroids and risk of fatal or severe COVID-19: a meta-analysis

Kow CS, Hasan SS

J Asthma, 2021 Feb 08.
PMID: 33461348 DOI: 10.1080/02770903.2021.1878531

Objective: With emerging of observational evidence, we aimed to perform a meta-analysis to summarize the overall effect of the chronic use of inhaled corticosteroids on the clinical outcomes in patients with coronavirus disease 2019 (COVID-19). Methods:Systematic literature search in electronic databases was performed to identify observational studies that investigated the preadmission use of inhaled corticosteroids on the risk of a fatal or severe course of illness in patients with COVID-19 and reported adjusted measures of association. Adjusted odds ratios or relative risks and the corresponding 95% confidence intervals from each study were pooled to produce pooled odds ratio and 95% confidence interval. Results: The meta-analysis revealed no significant difference in the risk for the development of a fatal course of COVID-19 with preadmission use of inhaled corticosteroids in patients with COVID-19 relative to non-use of inhaled corticosteroids (pooled odds ratio=1.28; 95% confidence interval 0.73-2.26). Similarly, the meta-analysis observed no significant difference in the risk for the development of a severe course of COVID-19 with preadmission use of inhaled corticosteroids in patients with COVID-19 relative to non-use of inhaled corticosteroids (pooled odds ratio=1.45; 95% confidence interval 0.96-2.20).Conclusions: Our findings assured the safety of continued use of inhaled corticosteroids during the COVID-19 pandemic.

Matched MeSH terms: Electronics
Chitin nanocrystals based complex fluids: A green nanotechnology

Kumar S, Foroozesh J

Carbohydr Polym, 2021 Apr 01;257:117619.
PMID: 33541647 DOI: 10.1016/j.carbpol.2021.117619

Chitin biopolymer has received significant attention recently by many industries as a green technology. Nanotechnology has been used to make chitin nanocrystals (ChiNCs) that are rod-shaped natural nanomaterials with nanoscale size. Owing to the unique features such as biodegradability, biocompatibility, renewability, rod-shape, and excellent surface and interfacial, physiochemical, and thermo-mechanical properties; ChiNCs have been green and attractive products with wide applications specifically in medical and pharmaceutical, food and packaging, cosmetic, electrical, and electronic, and also in the oil and gas industry. This review aims to give a comprehensive and applied insight into ChiNCs technology. It starts with reviewing different sources of chitin and their extraction methods followed by the characterization of ChiNCs. Furthermore, a detailed investigation into various complex fluids (dispersions, emulsions, foams, and gels) stabilized by ChiNCs and their characterisation have been thoroughly deliberated. Finally, the current status including ground-breaking applications, untapped investigations, and future prospective have been presented.

Matched MeSH terms: Electronics

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