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This work ensemble the structural features of Porous Silicon (PS) layers which are being fabricated employing modified stain etch method. Additionally, this study also categorizes the optimal etching parameters which are extensively used to grow Porous Silicon (PS) layers enabling Metal Induced Vapor Phase Stain Etching methodology. Various growth conditions are considered to fabricate uniform porous structures. The structural morphology of PS layers has been studied in scanning electron microscopy (SEM) that reveals macroporous nature of pore morphology supported by investigation of optical properties. This has been supported by characterizing ultraviolet-visible (UV-VIS) spectrophotometer absorption spectra. Surface and optical investigations discover uniform porous structure which augments the size of silicon substrate. This augmented surface of planar silicon substrate can be used as sensing platform for different kinds of sensors.

Micro-grid integrates the different distributed renewable energy resources such as solar, wind, and biomass. It can operate either in the stand-alone condition or in synchronization with the utility grid. Extensive research is being done on the implementation of SCADA systems for micro-grids that perform efficiently and are cost-effective. The development of effective and cost-effective real-time data acquisition and remote monitoring systems for micro-grid is essential to study the generated and consumed power quality measurement, stability, reliability, and maintenance optimization. Incomplete data and inaccurate measurement of energy output can lead to false conclusions and lost revenue. In this work, we have used Raspberry Pi for data communication and remote monitoring in a solar-wind-biogas integrated micro-grid system. Data acquisition has been done from smart meters of Elite 440-443 series of Secure Pvt. Ltd. Once the data comes to Raspberry Pi it has been used for different purposes like data display, warnings as parameters go off-limit and online remote monitoring. The operation, results and future scope of the developed data communication and remote monitoring system have been studied and analyzed in detail.

Non-invasive ultrasound imaging is an emerging approach for detection of prostate cancer. However appropriate segmentation of ultrasound images of prostate tissue is challenging due to their inherent complex structure and heterogeneity. To overcome such limitation, sonoelastography is a promising method for cancer detection based on variation in tissue stiffness. In this study, a scaling based segmentation algorithm has been developed for sonoelastography (SE) images of prostate. Proposed algorithm converts the input color SE image in the form of a parametric image by representing pixels in terms of elasticity values. Further, segmentation of images was performed through Otsu's multilevel method. Segmentation results are verified by expert clinician justifying the validation of the method for probable use in segmentation of SE images.

Cellular auto-fluorescence along with morphological and cytoskeletal features were assessed in lung cancer cells undergoing induced epithelial mesenchymal transition (EMT). During EMT progression, significant increase was observed in cellular aspect ratio (AR), filamentous (F)-actin and green auto-fluorescence intensities while blue intensity decreased. These features were provided to a kernel classification framework. The classification accuracy were impressive, thus these features along with the classification technique can be considered as suitable tools for automated grading of lung cancer cells undergoing EMT progression.

In the present work, we have considered the daily signal of Solar Radio flux of 2800 Hz recorded daily by radio telescopes near Ottawa (operated during 14th February, 1947–31st May, 1991) and Penticton, British Columbia, Dominion Radio Astrophysical Observatory (operating since 1st June, 1991) during the period from 29th October, 1972 to 28th February, 2013. We have applied FIR nonlinear phase filter on the present discrete signal to denoise it. The memory of this denoising signal has been analyzed and it indicates short memory trend (anti-persistent) hidden in this spectrum. Then we have examined whether the signal possesses stationary properties. On the basis of autocorrelation analysis, quasi or partly stationary nature of the spectrum has been revealed.

Remarkable effects on the records on Integrated Field Intensity of Atmospherics (IFIA) over Kolkata (latitude: 22.56° N, longitude: 88.5° E) at 3 kHz and 9 kHz are observed due to severe electrical activity in a thunderstorm, AILA, followed by severe thundershowers and lightning. The analyses and evaluation of the recorded data have been presented here.

Natural product like honey is well known for its compositional diversity, medicinal properties including anti-inflammatory role, wound repair efficacy and nutritional competence. This multi-dimensional character of honey attracts regenerative medicine researchers. However, flow behavior of honey restricts its applications as a sustainable biomaterial matrix. In this juncture this study develops honey-biomaterial formulations and fabricates fibrous scaffold through wet spinning technique towards regenerative medicine applications. The cell culture study demonstrates the bio-compatibility of the fabricated constructs for fibroblasts (3T3) and keratinocyte (HaCaT) through MTT assay and by scanning electron microscopy regarding adhesion and penetration of cells on the scaffold. Better performance has been exhibited by the honey-biomaterial based scaffolds in comparison to alginate fibrous construct. This study also shows better expression of prime molecules like collagen I and III in 3T3 and p63 and E-cadherin in HaCaT on honey based matrix than that of alginate matrix or control group. Thus present work develops a honey-based fibrous matrix with biocompatible interface for plausible tissue engineering applications.

Imaging bio-molecules especially in tissues, cells and even in in-vitro live conditions require expertise not only in staining and tagging of the particular molecules of interest but also their imaging so as to make any meaningful analysis and quantification of the obtained images. This necessitates a microscopic facility which can grab fluorescent images with minimum bleaching of the dyes and gives clear and crisp images without the blur caused by out of focus light. In this context ApoTome provides an alternative with metal halide light source and structural illumination with the help of grids, along with integrated image processing modality to generate images with digital interface. In the current study ApoTome was used to grab images of p63 and E-cadherin on histological sections of Oral Submucous Firosis an oral pre-cancer. The obtained images could aptly localize the expression of p63 and E-cadherin and distinguish the early and advanced stages of the precancer and did not show any effect of photo-bleaching. This demonstrated the applicability of ApoTome and its potential impact on diagnostics.

Confluent monolayers of cells in culture media are usually fragile and are susceptible to mechanical disruption. To assess the growth and migration of the cells towards recovery, the mechanical disruption is often done deliberately to perform wound healing assay. In such analysis, after a scratch in the cell monolayer, electrical characterization has been done to provide related quantitative description of the cellular behavior compared to the microscopic observation. In this direction for cellular electrical characterization, biosensors are usually designed with photolithographically patterned electrodes which are of the dimensions of the cells. This increases the cost and complexity of the analysis. Here we report the electrical characterization of in vitro wound healing for keratinocytes monolayer in DMEM-F12 medium with a low cost and sensitive macroporous silicon platform using simple electrode geometries for the first time. Impedance spectroscopy results show that there is a distinct difference between the electrical properties like the effective capacitance and the resistance of the keratinocytes (HaCaT) in the frequency range from 100Hz to 1MHz at two different time instants after wounding. The difference in the electrical properties has been qualitatively explained with the microscopic and immunocytochemical findings. This analysis may help to assess the cell behaviour during its growth and repair through a less complex and low cost electrical route.

Investigation of electrical properties along with molecular expressions of the keratinocyte and fibroblast under different physiological conditions can provide insight into their functioning which can contribute significantly towards skin tissue engineering application. For electrical characterization, cell based biosensors are usually designed with photolithographically patterned electrodes which are of the dimensions of cells. This increases cost and complexity of the analysis. In this paper, we report electrical characterization of keratinocyte and fibroblast cells, cultured in DMEM-F12 and DMEM media with a low cost and sensitive macroporous silicon platform using simple electrode geometries for the first time. Impedance spectroscopy results show that, there is a distinct difference between the electrical properties like effective capacitance and resistance of HaCaT (keratinocyte) and 3T3 (fibroblast) cells in the frequency range from 100Hz to 1MHz. The keratinocyte cells are observed to possess lower impedance than the fibroblast cells. The differences in the electrical properties have been correlated with the immunocytochemically detected prime molecular expressions of these cells. This multimodal analysis will help in the estimation of the degree of normalcy of these cells through a less complex and low cost electrical route.

Non-invasive visualization of wound bed with depth information is important to understand the tissue repair under therapeutic interventions. In this context, present study performs skin swept source-optical coherence tomography (i.e. optical biopsy/OCT) and correlates findings with histo-pathological observations on different types of traumatic non-healing wounds under honey dressing. Correlation between OCT and microscopic observations were explored especially in respect to progressive growth and maturation of the epithelial and sub-epithelial components. Characteristic transition of uniform hypo-lucid band for de-pigmented zone to wavy highly lucid band for the pigmented zone in the OCT images could be directly correlated with the microscopic findings on transformation of flattened pre-mature epithelium of de-pigmented area to thicker and matured epithelium with rete-pegs in pigmented zone. This correlated evaluation of multimodal images demonstrates the applicability of SS-OCT in wound research and importance of integrated approach in validation of newer technology.