Microheater: Material, design, fabrication, temperature control, and applications—a role in COVID-19

Heating plays a vital role in science, engineering, mining, and space, where heating can be achieved via electrical, induction, infrared, or microwave radiation. For fast switching and continuous applications, hotplate or Peltier elements can be employed. However, due to bulkiness, they are ineffective for portable applications or operation at remote locations. Miniaturization of heaters reduces power consumption and bulkiness, enhances the thermal response, and integrates with several sensors or microfluidic chips. The microheater has a thickness of ~ 100 nm to ~ 100 μm and offers a temperature range up to 1900℃ with precise control. In recent years, due to the escalating demand for flexible electronics, thin-film microheaters have emerged as an imperative research area. This review provides an overview of recent advancements in microheater as well as analyses different microheater designs, materials, fabrication, and temperature control. In addition, the applications of microheaters in gas sensing, biological, and electrical and mechanical sectors are emphasized. Moreover, the maximum temperature, voltage, power consumption, response time, and heating rate of each microheater are tabulated. Finally, we addressed the specific key considerations for designing and fabricating a microheater as well as the importance of microheater integration in COVID-19 diagnostic kits. This review thereby provides general guidelines to researchers to integrate microheater in micro-electromechanical systems (MEMS), which may pave the way for developing rapid and large-scale SARS-CoV-2 diagnostic kits in resource-constrained clinical or home-based environments. Graphical abstract: [Figure not available: see fulltext.

Review on Climate Control Chamber studies in studying plant environment interaction under climate change scenarios

This Technical brief summarizes some of the studies conducted on rice using a climate control chamber and outlines the studies that will be undertaken in the Climate Control Chamber facility that has been established at the Agro Climate Research Center at Tamil Nadu Agricultural University, Coimbatore. In recent years a numbers of technologies have been developed to study the impact of climate change on agricultural systems. Crop response to climate change could be studied by using a climate control chamber and data base generated using these facilities will be more realistic for impact assessment analysis under changing climatic conditions. Most of the research on plant response to climate change have been studies conducted under a controlled environment. Controlled climatic condition technologies have been successfully applied to study the response of plant to increasing temperature, green house gases and light quality variation

Regeneration of chitosan after heavy metal sorption

266-269This study presents desorption of Cr(VI) ions from chitosan by various eluants (dilute mineral acids and organic acids). A maximum of 88% of Cr (VI) was desorbed from metal loaded chitosan with 0.1 M H2SO4 without any physical damage to adsorbent. Numerical optimization has been carried out by a central composite design (CCD) in response surface methodology (RSM). Chitosan was regenerated by successive washing with deionised water many times until a neutral pH was obtained. Regenerated adsorbent/chitosan was dried and used to initiate another cycle of sorption and desorption. Absence of noticeable change in adsorption capacities of reused adsorbent confirms reusable potential of chitosan

Application of response surface methodology for adsorption of Cr(VI) from wastewater streams by chitosan

283-290The performance of chitosan as an adsorbent in the removal of chromium ion (Cr(VI)) from wastewater in batch and continuous modes has been investigated. The column performance of Cr(VI) adsorption onto chitosan has been studied at different bed height (3-9 cm) and flow rate (50-200 mL/min). The column has been designed based on the break through curves. Initially, adsorption tests of Cr(VI) on chitosan have been carried out in batch modes. The effects of pH, chitosan concentration, Cr(VI) concentration, contact time and shaking speed on the removal of Cr(VI) from synthetic and industrial wastewater have been studied. The highest adsorption capacity of 99.2% has been observed in the recycle column<span style="mso-bidi-font-weight: bold">. An ideal experimental design has been carried out based on central composite design (CCD) with response surface methodology (RSM) using the design expert software 8.0.6.1 to evaluate the effect of the different parameters on Cr (VI) adsorption capacity in batch mode and continuous mode. A multiple response method is applied for optimization of process parameters. </span

Comparison Statistical Rice Yield Prediction with Multiple Weather Parameters

Advance knowledge of harvestable products, especially essential food crops such as rice, wheat, maize, and pulses, would allow policymakers and traders to plan procurement, processing, pricing, marketing, and related infrastructure and procedures. There are many statistical models are being used for the yield prediction with different weather parameter combinations. The performance of these models are dependent on the location’s weather input and its accuracy. In this context, a study was conducted at Agro Climate Research Centre, Tamil Nadu Agricultural University, Coimbatore during Kharif (2020) season to compare the performance of four multivariate weather-based models viz., SMLR, LASSO, ENET and Bayesian models for the rice yield prediction at Tanjore district of Tamil Nadu State with Tmax, Tmin, Mean RH, WS, SSH, EVP and RF.&nbsp; The results indicated that the R2, RMSE, and nRMSE values of the above models were ranged between 0.54 to 0.79 per cent, 149 to 398 kg/ha, 4.0 to 10.6 per cent, respectively. The study concluded that the Bayesian model was found to be more reliable followed by LASSO and ENET. In addition, it was found that the Bayesian model could perform better even with limited weather parameters and detention of wind speed, sunshine hours and evaporation data would not affect the model performance. It is concluded that Bayesian model may be a better option for rice yield forecasting in Thanjavur districts of Tamil Nadu

Future Projections of Rainfall for Tamil Nadu from Coupled Model Intercomparison Project- 6 (CMIP6)

Precipitation is a crucial input for agriculture and living things in the world, which changes drastically under a warmer climate due to climate change. Hence, the study was carried out to project the changes in annual and seasonal precipitation based on the France Centre National de Recherches Météorologiques (CNRM-CM6) model. In the present study, Coupled Model Intercomparison Project phase six (CMIP6) datasets were used for two SSP scenarios: SSP2-4.5 and SSP5-8.5 and three-time slices for the future viz., near (2021–2050), mid (2051–2080) and end-century (2081–2099) and base period (1991–2020) dataset obtained from the India Meteorological Department (IMD) was used to compare with the future climate over Tamil Nadu. The result revealed that the highest positive mean deviations in annual (81%), SWM (21%), NEM (79%) and summer (163%) were observed in the projected precipitation under the SSP5-8.5 scenario during the Near, mid, near and mid-century respectively. For winter, SSP2-4.5 showed the highest mean deviation of 122% in the near century. According to the three future time scale simulations for the twenty-first century, annual rainfall is predicted to increase by 81% in the near future and 19% in the mid-century, while it is expected to decline by 1.5% at the end of the century under SSP5-8.5. In the SSP2-4.5 scenario, rainfall would increase by 1% in the near future, decrease by 30% in the end century and decrease by 30.5% in the mid-century. From the result, it is concluded that there would be an increase in heavy precipitation occurrences at the near, mid and end of the 21st century under both the SSP5-8.5 and SSP2-4.5 scenarios. These findings might be helpful in framing future agricultural water management regulations to deal with threats from heavy precipitation and researchers to study precipitation changes at the global level

Garlic Peel Surface Modification and Fixed-Bed Column Investigations towards Crystal Violet Dye

Garlic peel, a low-cost agro-waste, was explored as an adsorbent for the remediation of wastewater containing the crystal violet (CV) cationic dye. The garlic peel was treated with NaOH at 1 : 1.5 ratios in order to modify the surface and increase its porosity. The surface-modified garlic peel was ground to a smaller size in order to increase its surface area and used as an adsorbent in the continuous column investigations. Column parameters such as bed height, flow rate, and initial concentration were optimised and found that optimal removal efficiency was achieved at 3 ml rate of flow, 3 cm column depth, and 100 mg l-1 initial concentration. The surface-modified garlic peel exhibited a higher loading capacity of 99.9 mg g-1 towards CV at optimised conditions. SEM investigations confirmed the surface modification and increase in porosity of the garlic peel. The column data was tending to fit well with Thomas and Yoon-Nelson’s models suggesting the scalability to an industrial level. Regeneration of MGP was successful with 0.01 M HCl solution. These results conclude that garlic peel is a potential agro-waste material that can be used to mitigate water pollution

ANTIHYPERGLYCEMIC AND ANTIOXIDANT ACTIVITY OF PRUNETIN IN STREPTOZOTOCIN-INDUCED DIABETIC NEPHROTOXIC RATS

In the present study, we evaluated the protective impacts of Prunetin (PRU; 5-hydroxy-3-(4-hydroxyphenyl)-7-methoxy-4H-chromen-4-one / 5,4'-dihydroxy-7-methoxyisoflavone) altering plasma lipid peroxides and antioxidant in streptozotocin (STZ)-induced diabetic nephrotoxic&nbsp;(DN) rats. Wistar albino rats were given a single intraperitoneal (i.p) dosage of 45 mg/kg of STZ to cause diabetic nephropathy, which was then treated with Group-III, an effective dose of prunetin of 80 mg/kg. We examined the levels of body weight, blood glucose, insulin, lipid peroxidation products, and antioxidants in experimental rats. In STZ -induced diabetic rats, we observed an increased blood glucose level and reduced levels of insulin as compared to control rats. Whereas prunetin administration to diabetic nephrotoxic-induced rats resulted in significantly lower blood glucose level and increased the insulin levels as compared to DN rats. In diabetic nephrotoxic rats, prunetin treatment enhanced the antioxidant enzymes activity in the liver and renal tissues. Overall, the finding suggests that prunetin have significant an antioxidant and hypoglycemic activity in STZ-induced Wistar rats by scavenging free radicals thereby reducing the risk of diabetic complecations

Patient dose analysis in total body irradiation through in vivo dosimetry

Total body irradiation (TBI) is a special radiotherapy technique, administered prior to bone marrow transplantation. Due to the complex nature of the treatment setup, in vivo dosimetry for TBI is mandatory to ensure proper delivery of the intended radiation dose throughout the body. Lithium fluoride (LiF) TLD-100 chips are used for the TBI in vivo dosimetry. Results obtained from the in vivo dosimetry of 20 patients are analyzed. Results obtained from forehead, abdomen, pelvis, and mediastinum showed a similar pattern with the average measured dose from 96 to 97% of the prescription dose. Extremities and chest received a dose greater than the prescription dose in many instances (more than 20% of measurements). Homogeneous dose delivery to the whole body is checked by calculating the mean dose with standard deviation for each fraction. Reasons for the difference between prescription dose and measured dose for each site are discussed. Dose homogeneity within ±10% is achieved using our in-house TBI protocol