Control on the size of copper oxide (CuO) in the nano range is a highly motivating approach to study its multifunctional nature. The present investigation reports a sol-gel derived Ni doped CuO ...nanoparticles (Cu1-xNixO). Rietveld refinement of the XRD spectra confirms the formation of single monoclinic phase of Cu1-xNixO nanoparticles having crystallite size within the range of 19–21 nm. Raman spectra show the presence of characteristics Raman active modes and vibrational bands in the Cu1-xNixO samples that corroborate the monoclinic phase of the samples as revealed by refinement of XRD data. The estimated band gap of pure CuO is found to be ∼1.43 eV, which decreases with the increase of dopant concentration into CuO matrix. This result is in line with estimated crystallite size. Magnetization curves confirm the weak ferromagnetic nature of Cu1-xNixO nanoparticles which reveal the DMS phase. This weak magnetic nature may be induced in the samples due to the exchange interaction between the localized magnetic d-spins of Ni ions and carriers (holes or electrons) from the valence band of pristine CuO lattice. Replacement of Cu+2 by Ni+2 ions into the host CuO lattice induces the magnetization. The quantified value of squareness ratio (S < 0.5) confirms the inter-grain magnetic interactions in the Cu1-xNixO nanoparticles which is also the reason of weak induced magnetization.
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•Cu1-xNixO nanoparticles were successfully synthesized via chemical sol-gel route.•Structural study shows the formation of single phase nanoparticles (19–21 nm).•Optical band gap of CuO (∼1.43 eV) found to red shifted on doping with Ni ion.•M-H loops show the weak ferromagnetism for Cu1-xNixO nanoparticles.•Present study reveals the DMS phase at room temperature.
Metabolic regulation is the key mechanism implicated in plants maintaining cell osmotic potential under drought stress. Understanding drought stress tolerance in plants will have a significant impact ...on food security in the face of increasingly harsh climatic conditions. Plant primary and secondary metabolites and metabolic genes are key factors in drought tolerance through their involvement in diverse metabolic pathways. Physio-biochemical and molecular strategies involved in plant tolerance mechanisms could be exploited to increase plant survival under drought stress. This review summarizes the most updated findings on primary and secondary metabolites involved in drought stress. We also examine the application of useful metabolic genes and their molecular responses to drought tolerance in plants and discuss possible strategies to help plants to counteract unfavorable drought periods.
Object recognition is a key research area in the field of image processing and computer vision, which recognizes the object in an image and provides a proper label. In the paper, three popular ...feature descriptor algorithms that are Scale Invariant Feature Transform (SIFT), Speeded Up Robust Feature (SURF) and Oriented Fast and Rotated BRIEF (ORB) are used for experimental work of an object recognition system. A comparison among these three descriptors is exhibited in the paper by determining them individually and with different combinations of these three methodologies. The amount of the features extracted using these feature extraction methods are further reduced using a feature selection (k-means clustering) and a dimensionality reduction method (Locality Preserving Projection). Various classifiers i.e. K-Nearest Neighbor, Naïve Bayes, Decision Tree, and Random Forest are used to classify objects based on their similarity. The focus of this article is to present a study of the performance comparison among these three feature extraction methods, particularly when their combination derives in recognizing the object more efficiently. In this paper, the authors have presented a comparative analysis view among various feature descriptors algorithms and classification models for 2D object recognition. The Caltech-101 public dataset is considered in this article for experimental work. The experiment reveals that a hybridization of SIFT, SURF and ORB method with Random Forest classification model accomplishes the best results as compared to other state-of-the-art work. The comparative analysis has been presented in terms of recognition accuracy, True Positive Rate (TPR), False Positive Rate (FPR), and Area Under Curve (AUC) parameters.
Zingiberaceae plants are well known for their use in ethnomedicine. Curcuma mutabilis Škorničk., M. Sabu & Prasanthk., is an endemic Zingiberaceae species from Western Ghats of Kerala, India. Here, ...we report for the first time, the anticancer potential of petroleum ether extract from C. mutabilis rhizome (CMRP) and a novel labdane diterpenoid, (E)-14, 15-epoxylabda-8(17), 12-dien-16-al (Cm epoxide) isolated from it. CMRP was found to be a mixture of potent bioactive compounds including Cm epoxide. Both the extract and the compound displayed superior antiproliferative activity against several human cancer cell lines, without any display of cytotoxicity towards normal human cells such as peripheral blood derived lymphocytes and erythrocytes. CMRP treatment resulted in phosphatidylserine externalization, increase in the levels of intracellular ROS, Ca
, loss of mitochondrial membrane potential as well as fragmentation of genomic DNA. Analyses of transcript profiling and immunostained western blots of extract-treated cancer cells confirmed induction of apoptosis by both intrinsic and extrinsic pathways. The purified compound, Cm epoxide, was also found to induce apoptosis in many human cancer cell types tested. Both CMRP and the Cm epoxide were found to be pharmacologically safe in terms of acute toxicity assessment using Swiss albino mice model. Further, molecular docking interactions of Cm epoxide with selected proteins involved in cell survival and death were also indicative of its druggability. Overall, our findings reveal that the endemic C. mutabilis rhizome extract and the compound Cm epoxide isolated from it are potential candidates for development of future cancer chemotherapeutics.
-Quantum computer is no longer a hypothetical idea. It is the world's most important technology and there is a race among countries to get supremacy in quantum technology. It is the technology that ...will reduce the computing time from years to hours or even minutes. The power of quantum computing will be a great support for the scientific community. However, it raises serious threats to cybersecurity. Theoretically, all the cryptography algorithms are vulnerable to attack. The practical quantum computers, when available with millions of qubits capacity, will be able to break nearly all modern public-key cryptographic systems. Before the quantum computers arrive with sufficient ‘qubit’ capacity, we must be ready with quantum-safe cryptographic algorithms, tools, techniques, and deployment strategies to protect the ICT infrastructure. This paper discusses in detail the global effort for the design, development, and standardization of various quantum-safe cryptography algorithms along with the performance analysis of some of the potential quantum-safe algorithms. Most quantum-safe algorithms need more CPU cycles, higher runtime memory, and a large key size. The objective of the paper is to analyze the feasibility of the various quantum-safe cryptography algorithms.
Rainfall is a principal element of the hydrological cycle and its variability is important from both the scientific as well as socio-economic point of view. This study presents an analysis based on ...the precipitation variation in Assam, India over 102 years from 1901 to 2002. Precipitation data from 21 stations have been collected. These data have been analyzed for both annual and seasonal variation. For trend analysis, Mann-Kendell and Sen’s slope estimator test were used. To compare seasonal variations, three seasons of winter, summer and monsoon have been considered. Mean annual precipitation varied from 2,074 mm (at Tinsukia) to 3,538 mm (at North Chahar Hills). The most probable year of change was 1959 in annual precipitation. Time series of the Standardized Precipitation Index (SPI) depict that near normal occurs in about 68 years out 102 years, and in 2.48 years out of 102 years there was an extreme wet. All these findings can help provide rational regulatory and policy in relation to water resources to maintain the health of the various ecosystems that make up Assam, India.
•The performance analysis of utility-scale canal-top PV system has been carried out.•Experimental results show the low performance of PV module on the water surface.•High degradation rate has been ...found in the present 10 MWp canal-top PV system.•Shunt resistance degradation of PV module has been observed on the water surface.•Evaporation reduction by PV cover on the water surface is found to be 29.1%.
The canal-top PV systems have different environmental conditions than the land-based system which may affect its performance and degradation rate. The performance and reliability of PV modules on the canal and reservoir are critical for ensuring the long lifetime, improvement and economic viability of the canal-top PV systems. The long-term performance analysis of the canal-top PV systems and their comparison with conventional land-based PV systems is not reported widely. The objective of the present study is to assess the suitability of PV systems on the canals for their large scale installations and reliable operation. In order to understand the long-term performance behavior of the PV systems on the canals, the performance and degradation analysis of world’s first commercial multicrystallinesilicon (Multi-Si) based 10 MWp canal-top PV system installed in the Indian state of Gujarat has been carried out for their initial 2 years 8 months operation. An experimental setup was fabricated to compare the performance of canal-top PV systems with the conventional land-based PV systems and measurements were carried out in the outdoor conditions for six months in the outdoor laboratory of Indian Institute of Technology Roorkee, India. To achieve a better understanding of the performance and degradation of PV modules, a single-diode PV model was developed to characterize the PV modules. Furthermore, the evaporation loss reduction by canal-top PV systems has not been reported widely and has been experimentally quantified under this study. The annual average performance ratio and degradation rate of 10 MWp canal-top PV system are found to be 77.85% and 1.93 ± 0.28%/year, respectively. Experimental comparison of water tank-based PV module and land-based PV module shows that the average performance ratio of Multi-Si module on the water surface is about 1.5% lower compared to land-based Multi-Si module which is contrary to the general perception of higher power production by the Multi-Si PV systems on the canals.
•A non-stationary meteorological drought index is developed using large-scale climate indices.•A copula-based bivariate analysis of drought properties is carried ...out.•Reliability-Resilience-Vulnerability of the non-stationary drought index is evaluated.
The most of the available drought indices do not incorporate the environmental changes in the present scenario of climate change. In an attempt to encompass the climate variability in the computation of meteorological drought, a non-stationary gamma distribution with climate indices in its location parameter as a covariate is proposed. The performance of the non-stationary drought is evaluated based on the statistical performance as compared to the stationary drought. Focusing on two Himalayan states in India, the meteorological drought events are described and assessed based on the stationary and non-stationary drought index. Moreover, the bivariate analysis of different drought properties is carried out and compared with the univariate analysis. The management indices such as reliability, resilience, and vulnerability are also computed based on the developed drought index. The results in the study indicate that in most of the cases the non-stationary drought index is capable of capturing the drought characteristics over the study areas. The variability in the probability density of different drought properties is observed under 12-month drought scale in most of the cases. During bivariate analysis, a compare difference is noticed between secondary and primary return periods. Moreover, higher reliability and resilience is noticed during 12-month scale drought period. The newly developed drought index and the copula-based analysis of drought properties provide a new concept for robust and effective management practices in the changing environment.
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