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Enzyme inhibitors are vital aspects for studying enzymes and are employed as drugs to treat certain disorders, thus implying pivotal role in drug discovery. In the current study, a series of triazole compounds 4(a-o) were synthesised to explore their inhibitory potential against α-glucosidase and urease enzymes. These derivatives with dichlorophenyl substituents were prepared by cyclization of thiosemicarbazides and their structures were confirmed through spectroanalytical techniques. The in vitro biological screening revealed that the compounds 4a, 4b, 4k, 4l, 4m, 4o having IC50 values of 121.09 ± 1.25, 137.22 ± 0.22, 110.4 ± 2.4, 114.79 ± 1.1, 146.72 ± 1.29, 94.21 ± 0.15 [µM] respectively, exhibited good potential α-glucosidase inhibition, in comparison to Acarbose: IC50 51.23 µM, while the compounds 4a, 4b, 4c, 4k, 4l, having IC50 values of 48.52 ± 0.39, 52.22 ± 1.37, 60.98 ± 0.34, 37.06 ± 0.51, 38.66 ± 1.7 [µM] respectively exhibited good potential for urease inhibition near to standard(Thiourea: IC50 24.14 [µM]). These in vitro findings were accompanied further by molecular docking simulations, which revealed significant binding interactions of the synthesized derivatives within the active sites of the enzymes.

The experimental reports of structural modification, mechanical and magnetic properties of the Saudi meteorite were studied and discussed. The meteorite specimen was studied using the following different characterization techniques like X-ray powder diffraction, scanning electron microscopy, backscattered electron imaging, Energy Dispersive X-Ray Analysis, magnetic property measurements and hardness testing (Rockwell, Vicker, Brinell). The compositional analysis of the meteorite revealed that the sample was mainly composed of an iron-nickel alloy role. The hardness testing showed that the meteorite consisted of a soft material with 22.5 HRC Rockwell hardness. The magnetic measurements of the meteorite specimen indicated that it is a soft ferromagnetic material. The magnetic saturation (Ms) of 0.701 emu/g was observed for the saturation field of (Hs) = 5025 Oe. A sensitive GM counter showed no traces of radioactivity. Mathematical modelling of hysteresis data is also performed using already available models. Few modified models are also proposed and evaluated for the goodness of fit. Finally, most suitable model is proposed as bi-exponential model based on the goodness of fit parameters.

Our study demonstrated the biological changes produced in the Rhabdomyosarcoma (RD) cell line triggered by the photochemical reaction between PHOTOGEM® (photosensitizing agent) and He-Ne laser light (wavelength = 632.8 nm of red light). The basic parameters of photodynamic therapy were optimized to study photosensitizer localization/uptake, PHOTOGEM® absorption spectra, cytotoxic effects, phototoxic effects, and morphological changes in the RD cell line. The experiment included three steps. First, spectrometric measurements were obtained to optimize the absorbance and optimal density of PHOTOGEM® in the experimental biological model (RD cell line). A neutral red assay was used to estimate the loss of cellular viability. Second, the RD cell line containing PHOTOGEM® was irradiated with laser light (dose up to 100 J/cm2). In addition, a non-fluorescent compound was used to determine the intracellular production of reactive oxygen species. The treated cells were examined and photographed. The optical density of the PHOTOGEM®-exposed RD cell line was insignificant after 0–2 h but increased significantly after 20 and 24 h. A photosensitizer concentration of 120 μg/ml and a red He-Ne laser dose of 100 J/cm2 having wavelength 632.8 nm produced the maximum phototoxic effect in the RD cell line. The cell viability of the PHOTOGEM®-labeled RD cells decreased to 65% in the absence of the laser dose, but there was significant cell viability loss under suitable laser exposure (100 J/cm2).

In this research work, the linear and nonlinear optical properties of linear low-density polyethylene (LLDPE) composites with anatase phase of titanium dioxide nanoparticles in different weight percentages are investigated. Solvent casting method have been used to synthesize the thin film of LLDPE/anatase nanocomposites. Thin films are characterized via XRD technique and field emission scanning electron microscope (FESEM). Wrinkles formed on the surface of thin films by adding the titanium dioxide. Linear optical and electrical parameters such as linear absorption coefficient, extinction coefficient, refractive indices, optical conductivity, and dielectric constants at various wavelengths from 190 nm to 2700 nm are determined for different weight percentages of nanoparticles in polymer nanocomposites. Z-scan technique has been employed to explore the nonlinear optical properties using CW laser at 532 nm wavelength. The nonlinearity is examined at various irradiance of laser to study the effect of irradiance on nonlinear optical properties. Pure LLDPE has saturable absorption (SA) at low laser irradiance. As the laser irradiance increases, the nonlinearity behavior turns from SA to reverse saturable absorption (RSA). The results show the suitability of the thin films for the applications in optical devices that involve the use of optical limiting properties of materials.

Copper oxide nanoparticle (CuO-NPs) attracts the attentions of human beings due to unique physicochemical and biological properties. The chemical and green synthesis approaches were used to synthesis of CuO-NPs and plant leaves extract Azadirachta indica (A. indica) was preferred in green synthesis approach. The XRD analysis was used to analyze the monoclinic crystal structure and calculate the average crystallite size in the range of 15 ∼ 16 nm. While, the information about different rotational and vibrational modes attached on the spectrum of CuO-NPs was identified by FTIR. After that the UV–VIS analysis provided the information about the absorbance spectrums in the range of 235 and 220 nm. The MTT assay was perfomed to investigate liver carcinoma (HepG2 cells) interaction and absorbance of CuO-NPs towards mentioned cell lines were recorded and loss in HepG2 cells viability. In an overall assessment, anticancer response of comparative study of CuO-NPs towards liver carcinoma treatment contributes significantly after successful demonstration of essential steps of suggested experimental study. Finally, comparative study of experimental and mathematical modeling of anticancer activity towards normal and liver cancer cell lines were conducted and investigated.

Introduction: In December 2019, the city of Wuhan, located in the Hubei province of China became the epicentre of an outbreak of a pandemic called COVID-19 by the World Health Organisation. The detection of this virus by rRTPCR (Real-Time Reverse Transcription-Polymerase Chain Reaction) tests reported high false negative rate. The manifestations of CXR (Chest X-Ray) images contained salient features of the virus. The objective of this paper is to establish the application of an early automated screening model that uses low computational power coupled with raw radiology images to assist the physicians and radiologists in the early detection and isolation of potential positive COVID-19 patients, to stop the rapid spread of the virus in vulnerable countries with limited hospital capacities and low doctor to patient ratio in order to prevent the escalating death rates. Materials and methods: Our database consists of 447 and 447 CXR images of COVID-19 and Nofindings respectively, a total of 894 CXR images. They were then divided into 4 parts namely training, validation, testing and local/Aligarh dataset. The 4th (local/Aligarh) folder of the dataset was created to retest the diagnostics efficacy of our model on a developing nation such as India (Images from J.N.M.C., Aligarh, Uttar Pradesh, India). We used an Artificial Intelligence technique called CNN (Convolutional Neural Network). The architecture based on CNN used was MobileNet. MobileNet makes it faster than the ordinary convolutional model, while substantially decreasing the computational cost. Results: The experimental results of our model show an accuracy of 96.33%. The F1-score is 93% and 96% for the 1st testing and 2nd testing (local/Aligarh) datasets (Tables 3.3 and 3.4). The false negative (FN) value, for the validation dataset is 6 (Fig. 3.6), for the testing dataset is 0 (Fig. 3.7) and that for the local/Aligarh dataset is 2. The recall/sensitivity of the classifier is 93% and 96% for the 1st testing and 2nd testing (local/Aligarh) datasets (Tables 3.3 and 3.4). The recall/sensitivity for the detection of specifically COVID-19 (+) for the testing dataset is 88% and for the locally acquired dataset from India is 100%. The False Negative Rate (FNR) is 12% for the testing dataset and 0% for the locally acquired dataset (local/Aligarh). The execution time for the model to predict the input images and classify them is less than 0.1 s. Discussion and conclusion: The false negative rate is much lower than the standard rRT-PCR tests and even 0% on the locally acquired dataset. This suggests that the established model with end-to-end structure and deep learning technique can be employed to assist radiologists in validating their initial screenings of Chest X-Ray images of COVID-19 in developed and developing nations. Further research is needed to test the model to make it more robust, employ it on multiclass classification and also try sensitise it to identify new strains of COVID-19. This model might help cultivate tele-radiology.

Pure and copper doped zinc oxide nanoparticles (Zn1−xCuxO) of different concentrations (x = 0.0, 0.03, 0.06 and 0.09 wt%) were synthesized by using co precipitation method. During the next phase, effect of Cu concentration on structural, electrical and optical properties of ZnO-NPs were investigated with the multiple techniques like XRD, UV–visible spectroscopy, FTIR, and two probe methods. The XRD analysis confirmed hexagonal wurtzite crystal structure having crystallite sizes ranging between 18.3 and 24.2 nm. Rotational and vibration mode of different functional groups (OH, CH, C = O and ZnO) were calculated using FTIR spectra. Moreover, the UV visible spectroscopy identified a band gap (3.10–2.30 eV) of pure and Cu doped ZnO-NPs. Finally, electrical properties like conductivity was increased and whereas, the resistivity decreased with increasing Cu dopant concentrations. Overall, addition of Cu as doping agent improved the structural, optical and electrical properties ZnO-NPs and could enable multiple further potential applications like solar cell, energy storage and other optoelectronic devices.

Zinc oxide (ZnO) has attracted significant interest due to its exceptional material characteristics like its wide band gap (3.37 eV) and the high exciton binding energy. However, the application of ZnO is constrained by the difficulty in obtaining P-type samples. In this study, p- type ZnO thin films were fabricated using the co-doping technique with ZnO and AlN targets. Different RF powers were used for ZnO to deposite the films. However, the power on AlN target was fixed at 90 W. The structural, optical and electrical properties of the prepared films were inspected. The results of XRD showed that all the films exhibited ZnO (002) peak of wurzite structure. The UV emission peaks (3.24 eV–3.53 eV) identified in PL spectra is possibly due to the recombination of free excitons. The Raman peaks which shown at 576.22 cm−1 and 274 cm−1 denote ZnO:AlN and ZnO:N respectively. The Hall measurements of the films deposited at RF powers of 250 W and 200 W for ZnO target exhibited n-type conduction with corresponding mobilities of 2.75 cm2 V−1 s−1 and 1.58 cm2 V−1 s−1 respectively with electron concentrations of 2.35 × 1018cm−3 and 5.26 × 1018cm−3, respectively. However, the films deposited using RF powers of (150, 175) W and 225 W for ZnO target exhibited p-type conduction with hole concentrations of 2.14 × 1017 cm−3, 2.37 × 1019 cm−3 and 3.68 × 1021 cm−3 with corresponding mobilities of 9.21 cm2 V−1 s−1, 0.129 cm2 V−1 s−1 and 3.41 × 10−3 cm2 V−1 s−1 respectively. Therefore, RF power values of (150, 175) W and 225 W might be ideal for dopants activation to obtain p-type ZnO.

The study focusses on synthesis and modification of structural, optical and electrical characteristics of nanostructured titanium dioxide anatase embedded Poly(methyl methacrylate) (PMMA) nanocomposite with different weight percentages (0.03, 0.06, 0.12, 0.18 and 0.24%) by the solvent casting method. Modification in the morphology of PMMA nanocomposites with an increasing amount of titanium dioxide anatase is studied by using a field emission scanning electron microscope (FE-SEM). Micrograms of FE-SEM show spherical shaped nanoparticles distribution in PMMA nanocomposites thin films. In optical characterization, transmission, optical band gaps, the real and imaginary part of dielectric constant, linear susceptibility, optical conductivity, refractive index and extinction coefficient are calculated using experimental data. It is observed that the optical band gap has an overall decreasing trend with increasing the weight percentage of TiO2 (anatase) in PMMA nanocomposites. It is also found that values of all electrical parameters decrease with increasing the weight percentage of TiO2 (anatase) in PMMA nanocomposites. All wavelength depending parameters are investigated in the wavelength range from 190 nm to 2700 nm. Single oscillator model is used to analyze the refractive index dispersion and estimation of the oscillator energy and dispersion energy of the films. The study is applicable to optical sensors and other optoelectronic devices.

Plasmonic metal nanoparticles are known to work as light-harvesting antennae and to enhance photocurrents of photovoltaic cells. Therefore, in this work, the effect of gold (Au) ions distribution on the efficiency of dye sensitized solar cells (DSSCs) has been investigated. Thin films of TiO2 have been deposited on FTO glass substrates by the doctor tape method. Au ions were then implanted on these films with different fluence rates (i.e., 2 × 1014, 4 × 1014 and 6 × 1014 ions/cm2). XRD results confirmed that TiO2 is present in the anatase phase up to a 4 × 104 ions/cm2 fluence rate. At a 6 × 1014 ions/cm2 fluence rate, one peak of rutile is obtained which confirmed that the film has mixed phases of TiO2. UV results show that dye is adsorbed into all photoanodes. Maximum dye absorption is seen at a fluence rate of 4 × 1014 ions/cm2. The energy conversion efficiency of DSSC is highly dependent on the fluence rate of Au. At a fluence rate of 4 × 1014 ions/cm2, the cell has a high short circuit current density (JSC) of 7.21 mA/cm2, resulting in a high efficiency (×) of 2.92%. Impedance spectroscopy shows that the cell formed by Au ions fluence rate of 4 × 1014 ions/cm2 has a low recombination rate of electron/hole pairs.

This work focuses on the performance of Al-doped CdS quantum dot (QD)/TiO2 solar cells. The devices were analyzed through current-voltage and capacitance-voltage measurements. It was observed from the analysis of absorption spectra that TiO2 nanowires improve the absorption of light of Al doped CdS QDs both in visible and near infrared (NIR) range. Current-voltage characteristics curve of Al doped CdS/TiO2 at different illuminations show that decrease in illumination (from 100 to 5 mW/cm2), affects the voltage and current correspondingly. Power-voltage curve at various intensities of light indicates that power of the solar cell increases with the increase of the bias voltage and reaches its maximum value at each value of light illumination intensity. The peak value of power at maximum illumination is 35 µW at 0.20 V and with decreasing illumination the peak value decreases. Capacitance-voltage measurements reveal that by increasing the bias voltage from −2.0 V to 0 V, the capacitance voltage indicates the rising trend. However, at 5 kHz and 10 kHz frequencies, it was observed that a marginal increase of capacitance was noticed with exceeding bias voltage. The results revealed that subsequent addition of the TiO2 nanowires significantly improved the output performance of QDSSC.

Dye sensitized solar cells (DSSCs) are attracting immense academic and industrial attention as a simple, low cost and potential photovoltaic device from last two decades. In a DSSC, photo-electrode is suggested as an important component which collects as well as transports the photo-excited electrons from sensitizer dye to external circuit. In this research, photoanodes of 1% copper doped Titanium dioxide (Cu-TiO2) have been prepared by doctor blade method on FTO-glass substrates. These photoanodes are implanted by Gold (Au) ions of energy 900 keV along with different exposure rate (1 × 104 and 4 × 104 ions/cm2). XRD pattern confirmed that all the photoanodes consist of anatase phase of TiO2. N719 dye is used as sensitizer in all films. UV–Visible absorption results show the absorbance peak of all films at 524 nm which confirmed the absorption of dye in photoanodes and the intensity of peaks increases with Cu doping and Au ions implantation. Solar simulation result showed that a maximum efficiency of about 2.15% is achieved by implanting gold ions with flounce rate of 4x104 ions/cm2 in Cu-TiO2 film. The present work suggest that optimization of the gold nanoparticles in the Cu: TiO2 layer plays a vital role in enhancing efficiency of DSSC. Keywords: Solar cell, Dye, Spectroscopy, Absorption