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The discovery of exogenous contrast agents (CAs) is one of the key factors behind the success and widespread acceptability of MRI as an imaging tool. To the long list of CAs, the newest addition is the chemical exchange saturation transfer (CEST)-based CAs. Among them, the diaCEST CAs are the safer metal-free option constituted by a large pool of organic and macromolecules, but the tradeoff comes in terms of smaller natural offset. Another major challenge for the CEST CAs is that they need to operate in the tens of millimolar concentration range to produce any meaningful contrast. The quest for high efficiency diaCEST agents has led to a number of strategies such as use of hydrogen bonding, use of equivalent protons, and use of diatropic ring current. Here, we present carbon quantum dot formation using hydrothermal treatment as a new strategy to amplify diaCEST contrast efficiency. We show that while the well-known analgesic drug lidocaine hydrochloride when repurposed as a diaCEST CA produces no contrast at the physiological pH and temperature, the carbon dots prepared from it elevate the physiological contrast to a sizable 11%. Also, the maximum efficiency at an acidic pH gets amplified by a factor of 2 to 46%. The study showed that the enhancement in CEST efficiency is reproducible and the pH response of these carbon dots is tunable through variation in synthesis conditions such as temperature, duration, and precursor concentration.

A Smartbin for waste management is presented in this work, as an attempt to maintain clean and hygienic environment. The concept of the Internet of Things (IoT) has been implemented through GSM module integrated with Arduino UNO to design this bin along with Bluetooth connectivity. The Bluetooth Controller App is employed for establishing connection with the Bluetooth module. The module is therefore leveraged to detect distance between the user and the bin, and the information enables the planning of an optimal route for the bin to move towards the user. As it detects the object, the lid of the bin opens automatically and allows the object to dispose the waste into it. The waste is then segregated into dry or wet particles and then the lid will get close automatically. Level indicators allow estimation of remaining capacity of the bin to store further waste. On exhaustion of the capacity of the bin, SMS-based notification is provided to the user via a GSM module. In this work, a low cost, user-friendly, economically viable waste management solution to control pollution is demonstrated.

Coronavirus disease (COVID-19) is an infectious disease that has posed a global health challenge caused by the SARS-CoV-2 virus. Early management and diagnosis of SARS-CoV-2 are crucial for the timely treatment, traceability, and reduction of viral spread. We have developed a rapid method using a Graphene-based Field-Effect Transistor (Gr-FET) for the ultrasensitive detection of SARS-CoV-2 Spike S1 antigen (S1-Ag). The in-house developed antispike S1 antibody (S1-Ab) was covalently immobilized on the surface of a carboxy functionalized graphene channel using carbodiimide chemistry. Ultraviolet-visible spectroscopy, Fourier-Transform Infrared Spectroscopy, X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM), Optical Microscopy, Raman Spectroscopy, Scanning Electron Microscopy (SEM), Enzyme-Linked Immunosorbent Assays (ELISA), and device stability studies were conducted to characterize the bioconjugation and fabrication process of Gr-FET. In addition, the electrical response of the device was evaluated by monitoring the change in resistance caused by Ag-Ab interaction in real time. For S1-Ag, our Gr-FET devices were tested in the range of 1 fM to 1 μM with a limit of detection of 10 fM in the standard buffer. The fabricated devices are highly sensitive, specific, and capable of detecting low levels of S1-Ag.

This research paper is aimed to deliver a novel approach to prepare a popular probiotic beverage i.e., kombucha from infusion of tea waste to valorize the by-product of tea industry. In this study, a GC-MS based approach in combination with preliminary in vitro biochemical analysis was used to investigate the metabolic profiles, especially the antioxidant compounds produced during the fermentation of waste tea infusion. Waste tea infusion was found to be rich in xanthosine, the precursor of caffeine while the fermented sample was seen to be rich in more bioactive secondary metabolites derived from the substrate compounds i.e., xanthosine and sucrose. In addition, GC-MS based metabolomics helped to propose biosynthesis pathways of the metabolome which suggest the later breakdown of xanthosine and other substrate components into microbial metabolites during fermentation process. These findings are expected to be useful for further studies on production of bioactive formulations from tea waste.

Tea is a major plantation crop and the socioeconomic pillar of Terai region of West Bengal. Use of various inorganic fertilizers may have increased the crop production but affected the environment badly. Importance of biomass of different trees in accumulation of carbon had long been known but few studies on characterization of biomass accumulation are reported. So, selection of different species for getting the good amount of organic nutrients is important. In tea plantation, various leguminous trees are used as shade trees. This research, conducted in the tea plantation of University of North Bengal, has provided some approaches which could possibly reduce the application of inorganic fertilizers. Different tests on physicochemical parameters, micronutrients status, biomass etc. were conducted with the collected plant litters. The results of this comparative analysis suggested and validated the beneficial effects of each shade tree in organically maintaining nutrient profile of tea plantation soil.

In this prospective study, children from 1-month to 12-years, admitted with positive IgM ELISA testing for scrub typhus, were enrolled over 1-year and administered an empirical single dose of azithromycin (10 mg/kg). All 189 (median age 4.84-years) children had fever with median duration of 8 days at admission. Shortness of breath, altered sensorium, headache, lymphadenopathy, hepatosplenomegaly, pallor, oedema and hypotension were the most prominent symptoms/signs. About 46% of children developed complications, among them hepatic, neurological and cardiovascular were most common. Our study showed a remarkable response to azithromycin, with mean defervescence of 32 h and no mortality. The presence of shortness of breath, headache, altered sensorium, hepatosplenomegaly, meningeal signs, severe anemia, leucocytosis, hyponatremia along with/without any of above mentioned three systemic complications were independent predictors for delayed treatment response by multivariate logistic regression analysis. Hepatic, neurological and cardiovascular complications are an emerging trend. Empiric azithromycin based on clinical suspicion of scrub typhus can be lifesaving.

Haria, the traditional rice based liquor of eastern India and Nepal, is an indigenous alcoholic beverage prepared by different ethnic communities where bakhar is used as starter culture which is a tablet like mixed culture of various yeasts, filamentous molds, and lactic acid bacteria etc. This research work was designed to make a fusion of tea infusion and bakhar to produce “Tea Haria”. Tea infusion and bakhar were co-cultured for fermentation which was further characterized by different physicochemical and biochemical parameters. In vitro assessment of antioxidant, antidiabetic, anti-ipid peroxidation activity and antibacterial activity were assessed. Primary investigations for qualitative characters on this fermented broth or tea haria revealed the presence of steroids, tannin, flavonoids, phenol, cardiac glycosides, coumarin, caffeine etc. Tea haria, the fermented broth showed high free radical scavenging activity. The antioxidant activity, acidity and alcohol percentage were seen to be gradually increased while brix and specific gravity of broth were decreased during the first fifteen days of fermentation. Gas chromatography-mass spectrometry analysis revealed the presence of thirty-three compounds including many potential antioxidant molecules and other bioactive agents which validated the qualities detected and estimated through in vitro assays in tea haria. Presence of alcohol with medicinally active compounds and antioxidant, antibacterial and other biological activities have made this tea haria a bioactive probiotic-fermented formulation and, furthermore, brought out the ethnic knowledge of haria fermentation, specifically, ethnic starter bakhar as a useful biotechnological tool which can be utilized in research and development of fermentation technology.

A battery energy storage system (BESS) can play a critical role in regulating system frequency and voltage in an islanded microgrid. A $\mu$ -synthesis-based robust control has been proposed for dc link voltage regulation of BESS for achieving frequency regulation and voltage quality enhancement of islanded microgrid. Variation in the operating condition of ac microgrid affects the operating condition of the BESS’ converter. This controller synthesis accounts for such uncertain variations as parametric uncertainty. The stability and performance of the proposed controller can be guaranteed for bounded parametric variations. The bounds on parameters are selected based on practical limitations of BESS. In this article, the proposed controller's performance is tested on an islanded CIGRE TF C6:04:02 benchmark low voltage ac microgrid system. The importance of dc link voltage regulation is analyzed based on performance comparison with a benchmark controller. The controller performance is also validated using a real-time Typhoon HIL emulator.

A comparison of different diacetamide isomers shows the influence of hydrogen-bonding networks in tuning the diaCEST MRI contrast efficiency.

The COVID-19 pandemic exposed health care workers to unique challenges facing a previously unknown virulent disease. A balance was needed between personal health and fulfilling professional duties. Previous research identified barriers in the willingness and ability of health care professionals to work in a hypothetical pandemic scenario. Our aim was to identify if such barriers existed amongst a largely Asian health care work force in delivering their professional responsibilities at the initial phase of COVID-19 pandemic. Methods: A GDPR compliant survey of 28 questions was designed using Microsoft forms. Social media (WhatsApp and Facebook messenger group) and professional emails were used to contact health care workers internationally. Data were analysed using Microsoft Excel and SPSS24. Results: 334 responded; 188 doctors (56·3%) and 90 nurses (26·9%). 236 participants lived in south Asia (70·7%) and 81 in Europe (24·3%). 215 out of 334 (64·4%) were Indians, 60 (18%) Bangladeshi and 41 (12·3%) Caucasian. A positive association between obesity (perceived) and fear of COVID-19 infection was found (OR 1·77 (95% CI 1·06, 2·98)). We didn't find any association between ages of the participants, country of residence, ethnicity or comorbidities with worry of being infected by COVID-19. Our respondents mostly remained satisfied with their profession. Only 37 out of 334 (11%) said they wished they were in a different profession. Conclusion: Contrary to predictive data, health care workers showed a more balanced approach in dealing with the COVID-19 pandemic from the very early days of the 1 pandemic according to real time data. MRCPCH, Consultant Respiratory Paediatrician, Kings College Hospital, London

Carbon dot formation through the hydrothermal treatment of amino-thioamide improves the diaCEST contrast efficiency.