This work demonstrates enhanced valley contrasting spin-momentum locked chiral states at the van der Waals interface of chiral L-cysteine and single layer (SL) MoS2 placed on a Si/SiO2 substrate at ...ambient conditions. Helicity dependent photoluminescence and resonance Raman measurements highlight spin-locked transitions for the chiral L-cysteine modified SL-MoS2 at ambient conditions. Selective adsorption of chiral L-cysteine dimer/cysteine stabilizes the in-plane effective magnetic field due to the Si/SiO2 substrate and blocks the intervalley spin relaxation. The observed polarization efficiency can be useful for improving the functionality of valley-based light emitting diodes and encoding information in logical devices.
Introduction: Coronavirus Disease-2019 (COVID-19) causes respiratory tract infections in human beings ranging from mild illnesses like common cold to severe disease like pneumonia. Currently, nucleic ...acid amplification tests Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR), Cartridge Based Nucleic Acid Amplification Test (CBNAAT) and TrueNat) and rapid antigen detection tests are approved for diagnostic purpose by Indian Council of Medical Research (ICMR). Medical interns, the primary contact healthcare personnel, need to be sensitised regarding proper utilisation of CBNAAT, so that rapid and accurate diagnosis of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can be made in comparison to the more commonly used RT-PCR technique. Aim: To evaluate the Knowledge, Attitude and Practices (KAP) of Bachelor of Medicine and a Bachelor of Surgery (MBBS) interns towards accessibility of CBNAAT in SARS-CoV-2 infection in a tertiary care hospital. Materials and Methods: A cross-sectional study was performed through questionnaire shared via online platform amongst 102 Medical interns working at College of Medicine and Sagore Dutta Hospital from 22nd August 2021 to 21st September 2021. Based on their response, KAP was assessed by using a three-point Likert Scale. The collected data was entered in Microsoft excel, and reported as frequencies and percentages. Results: Among 102 internees, 84 interns responded. Among 84 medical interns 31% had good, 50% had average whereas 19% had poor level of knowledge. About 58 (69%) agreed that CBNAAT can be used as a method for rapid diagnosis of SARS-CoV-2. About 75 (89.3%) answered that they are sending samples for COVID-19 testing. Only 56 (66.7%) agreed that CBNAAT should be recommended. Conclusion: The present study revealed that majority of the MBBS interns had positive attitude towards different aspects of CBNAAT utility but most of them had gaps in their KAP. This demands extra efforts to sensitise and train them adequately.
Selection of plant extracts as bioactive phytochemical source to synthesize nanoparticles is highly demanding due to the biocompatibility, nontoxicity, and cost-effectiveness over other available ...physical and chemical methods. Here, for the first time, Coffee arabica leaf extracts (CAE) were used to produce highly stable silver nanoparticles (AgNPs) and the corresponding bio reduction, capping and stabilization mechanism mediated by dominant isomer 5-caffeoylquinic acid (5-CQA) is discussed. UV-Vis, FTIR, μRaman spectroscopy, TEM, DLS and Zeta potential analyzer measurements were employed to characterize these green synthesized NPs. The affinity of 5-CQA capped CAE-AgNPs to thiol moiety of amino acid is utilized for the selective as well as sensitive detection of L-cysteine (L-Cys) to a low detection limit of 0.1 nM, as obtained from its μRaman spectra. Hence, the proposed novel, simple, eco-friendly, and economically sustainable method can provide a promising nanoplatform in the field of biosensors compliant with large-scale industrial production of AgNPs without aid of further instrumentation.
Background: Food handler is any person who handles food, regardless whether he/she actually prepares or serves it. The chances of food getting contaminated depend on their knowledge of food hygiene ...and its application. Any incidence of food-borne diseases that affect medical students and doctors can result not only in sickness absenteeism but also in case of transmission of pathogen to patients and their relatives which ultimately affect the health care services to a great extent. Therefore, the present study was conducted to assess knowledge, attitude, and practice (KAP) of food hygiene and safety among food handlers of eating establishments of medical college and attached hospital. Materials and Methods: A present, cross-sectional study conducted among all the food handlers of food establishments in the premises of Medical College and attached General Hospital in Pune in June-July 2017 selected by the universal sampling method. They were interviewed with prestructured questionnaire. The data were entered in MS excel and analyzed using Epi Info version 7.2. Results: A total 105 food handlers, mean age of 29.4 ± 11.02 years were enrolled. Maximum study participants 71 (67.6%) had good knowledge, 74 (70.5%) had favorable attitude, and 82 (78.1%) had good practice. There was positive relationship between both knowledge and attitude, knowledge and practice, also attitude and practice. It can be anticipated that as knowledge will increase, attitude, and practice will improve accordingly. Conclusion: Education, training, and the development of food safety certification examinations are the key components in the process of ensuring that food handlers are proficient in and knowledgeable about food safety and sanitation principles.
Recent observations have demonstrated that the photoelectric conversion properties of perovskite materials are intimately related to the presence of superlattice structures and other unusual ...nanoscale features in them. The low-dimensional or mixed-dimensional halide perovskite families are found to be more efficient materials for device application than three-dimensional halide perovskites. The emergence of perovskite solar cells has revolutionized the solar cell industry because of their flexible architecture and rapidly increased efficiency. Tuning the dielectric constant and charge separation are the main objectives in designing a photovoltaic device that can be explored using the two-dimensional perovskite family. Thus, revisiting the fundamental properties of perovskite crystals could reveal further possibilities for recognizing these improvements toward device functionality. In this context, this review discusses the material properties of two-dimensional halide perovskites and related optoelectronic devices, aiming particularly for solar cell applications.
Introduction: Hybrid Problem-Based Learning (h-PBL) is a type of teaching-learning technique that incorporates both inperson learning and virtual learning via hybrid classroom tools. It reportedly ...increases student engagement, positively impact their learning process and improve communication skills. During Coronavirus Disease 2019 (COVID-19) times, its applicability was further enhanced as it allowed the flexibility of teaching as well as learning from home to both teachers and students. Aim: To assess the perception and experience of 2nd phase MBBS students after undergoing training by the h-PBL method. Materials and Methods: A cross-sectional study was conducted on 2nd phase MBBS students in the Department of Microbiology at College of Medicine and Sagore Dutta Hospital, Kolkata from 15th March to 14th April 2022. A total of 111 students of 2nd phase MBBS of the college gave an informed consent to be part of the study. All inductees underwent a structured training by h-PBL technique following which their perception and experience about the exercise was sought via questionnaire. Data were presented in frequency and percentage. Association between mean scores of male and female participants was calculated by Chi-square test. Results: Out of the 111 participants, 58 (52.2%) were male and 53 (47.8%) were female with mean age of 19.5±0.5 years (range 18- 22 years). The h-PBL technique was perceived to be motivating for self-directed learning by 97 (85.6%) of the respondents. A total of 107 (96.4%) students agreed that h-PBL is more effective than traditional teaching for acquiring both theoretical and practical knowledge, learning and understanding topics correctly and also identifying and rectifying their deficiencies in knowledge and skills. More than 90% participants (102 of 111) felt that h-PBL has more potential than traditional teaching to establish fruitful student-teacher interaction and provide better feedback opportunities. Overall student satisfaction in our study showed 96.4% agreement (107 of 111). Conclusion: The students considered h-PBL model to be better than traditional teaching to help them acquire theoretical knowledge and practical skills. They also felt that it improved their communication skills, teamwork ethics and motivated them to undertake self-directed learning.
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•Grain boundary defect passivation.•Points defects neutralisation.•Environmental stability.•Surface defects neutralisation.•Passivation of transporting layer.
Organo-metallic ...perovskite solar cells emerge as a disruptive technology having the potential to revolutionise solar photovoltaic harvesting industries and become one of the most efficient and low-cost technologies due to their fabrication methods and flexible designs. However, the light-harvesting capabilities of these devices are still limited by excessive non-radiative recombination arising from the surface/volume defects which inhibit its industrial applications. Therefore, the process of elimination of these defects commonly known as passivation is very much essential. This review illustrates and summarizes categorically these defects and their origins and demonstrates different passivation techniques that have been adopted recently to improve the efficiency and stability of hybrid perovskite materials toward its potential solar cell applications.
Surgical Site Infection (SSI) is the most common healthcare associated infection that could be averted by antibiotics prophylaxis against the probable offending organisms. As
has been playing a ...substantial role in the aetiology of SSIs, Methicillin Resistant
(MRSA) happens to be a problem while dealing with the postoperative wound infection.
To determine the prevalence of SSI caused by MRSA and the antibiotic sensitivity pattern of MRSA.
A cross-sectional study was conducted at Nil Ratan Sircar Medical College, Kolkata, West Bengal from July 2009 to December 2012. A total of 19,359 surgical procedures were done of which 3003 culture positive SSIs have been documented. The clinical samples were collected from patients of both sexes and all ages suspected to be suffering from SSI from different specialities. Samples were processed according to CLSI, 2007 guidelines. The isolated strains of
were screened for MRSA by detection of resistance to Cefoxitin disc (zone of inhibition was ≤21 mm) and slidex staph latex agglutination tests were done on cefoxitin resistant strains to spot phenotypic expression of
gene. Then PCR was performed for detection of
gene. Antibiotic sensitivity test was done following Kirby Bauer technique.
In this 3½ year study, 1049
(34.93%) were reported from 3003 cases of SSI followed by
(20.34%),
spp. (18.08%),
spp. (7.99%),
spp. (7.49%) respectively. Among the
267 strains were derived as MRSA (25.45%). MRSA were isolated from 167 (62.54%) male patients and 100 (37.45%) female patients having surgical site infections. Inpatients and outpatients distribution of MRSA were 235 (88.01%) and 32 (11.98%) respectively. Majority of the MRSA cases were reported from Surgery (12.49%) and Orthopaedics (11.85%) departments in the age group above 75 years (15.63%). The MRSA strains have been found to be 100% sensitive to linezolid and tigecycline followed by fucidin (92.51%), mupirocin (88.39%), levofloxacin (75.66%) and doxycycline (72.28%). No vancomycin resistant strains were detected, but 3 strains (1.12%) were found to be intermediately susceptible to it (VISA). Incidence of MRSA in SSI has been decreased by 15.17 % in 2012 in comparison to 2009. PCR revealed
gene was present in 96.25% of cefoxitin resistant
strains.
being the predominant organism causing SSIs, MRSA needs the attention for its resistance to commonly used antibiotics in the hospital like penicillin, cephalosporin group of drugs. Regular monitoring of the MRSA, involved in the SSI of a particular setup is the basic requirement to trim down the incidence of the postoperative wound infections by proper antibiotic prophylaxis.
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•PCA of Raman data discriminates molecular structure of HEWL protein and fibrils.•SD of scores in PCA plots determines variability in the structure within a species.•Overall structure ...significantly differs for fibrils grown at different pH values.•Overall structure of fibrils grown at different pH values in Cu(II) has similarity.•Presence of Cu(II), inhibits the formation β-sheet component in HEWL fibrils.
The difference in molecular structure of native HEWL and its fibrils, grown at a pH value near physiological pH 7.4 and at a pH value just above the pI, 10.7 in presence and absence of Cu(II) ions, is discussed. We focus on differences between the molecular structure of the native protein and fibrils using principal component analysis of their Raman spectra. The overlap areas of the scores of each species are used to quantify the difference in the structure of the native HEWL and fibrils in different environments. The overall molecular structures are significantly different for fibrils grown at two pH values. However, in presence of Cu(II) ions, the fibrils have similarities in their molecular structures at these pH environments. Spectral variation within each species, as obtained from the standard deviations of the scores in PCA plots, reveals the variability in the structure within a particular species.
In vitro fibrillation of hen egg white lysozyme (HEWL) causes complete reduction of Cu(II) to Cu(I) at pH 7. Here in the present article, we have shown the presence of both Cu(II) and Cu(I) at pH 11 ...during fibrillation of HEWL using electron paramagnetic resonance and Raman spectroscopy. Our results suggest the existence of a partially reducing environment during fibrillation of hen egg white lysozyme at pH 11. The fibrillation process is governed by the pH of the solution and maximum fibrillation is found to occur at pH 11. Fibrils formed in the absence of Cu(II) were also found to cause significant hemolysis of RBC.
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