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Cryogenian magmatism and crustal reworking in the Southern Granulite Terrane, India
Understanding Neoproterozoic crustal evolution is fundamental to reconstructing the Gondwana supercontinent, which was assembled at this time. Here we report evidence of Cryogenian crustal reworking in the Madurai Block of the Southern Granulite Terrane of India. The study focuses on a garnet-bearing granite-charnockite suite, where the granite shows in situ dehydration into patches and veins of incipient charnockite along the contact with charnockite. The granite also carries dismembered layers of Mg-Al-rich granulite. Micro-textural evidence for dehydration of granite in the presence of CO2-rich fluids includes the formation of orthopyroxene by the breakdown of biotite, neoblastic zircon growth in the dehydration zone, at around 870C and 8 kbar. The zircon U-Pb ages suggest formation of the granite, charnockite, and incipient charnockite at 836 73, 831 31, and 772 49 Ma, respectively. Negative zircon ?Hf (t) (-5 to -20) values suggest that these rocks were derived from a reworked Palaeoproterozoic crustal source. Zircon grains in the Mg-Al-rich granulite record a spectrum of ages from ca. 2300 to ca. 500 Ma, suggesting multiple provenances ranging from Palaeoproterozoic to mid-Neoproterozoic, with neoblastic zircon growth during high-temperature metamorphism in the Cambrian. We propose that the garnet-bearing granite and charnockite reflect the crustal reworking of aluminous crustal material indicated by the presence of biotite + quartz + aluminosilicate inclusions in the garnet within the granite. This crustal source can be the Mg-Al-rich layers carried by the granite itself, which later experienced high-temperature regional metamorphism at ca. 550 Ma. Our model also envisages that the CO2 which dehydrated the garnet-bearing granite generating incipient charnockite was sourced from the proximal massive charnockite through advection. These Cryogenian crustal reworking events are related to prolonged tectonic activities prior to the final assembly of the Gondwana supercontinent. 2015 Taylor & Francis. -
Cryptic species and taxonomic troubles: A rebuttal of the systematic treatment of the Asian ladies' tresses orchids (Spiranthes species; Orchidaceae) by Pace et al. (2019)
In a recent research article by Pace et al. (2019), the authors claimed to have used information from phenology, morphology and molecular phylogenetics in their nomenclatural review of the Spiranthes sinensis complex. However, there are several scientific and botanical nomenclature issues with the Pace et al. (2019) paper in addition to its many errors and misinformation, which can be severely misleading and have the potential to affect our understanding of the highly complex Asian Spiranthes group. Here, we compare and critique their study in light of our study published prior to the article in the Botanical Journal of the Linnean Society. We suggest that the authors should have resorted to improved and new molecular data and a truly integrative analysis to support: (1) re-circumscription of the S. sinensis species complex for each of the six species they recognized, and the treatment of S. hongkongensis as a hybrid; and (2) all the new synonymies they proposed for Asian Spiranthes. 2020 The Linnean Society of London, Botanical Journal of the Linnean Society, 2020, 194, 375-381 -
Cryptocurrencies: An Epitome of Technological Populism
From a global perspective, which holds significant cryptocurrencies, this study discusses the volatility and spillover effect between the whales cryptocurrencies. Volatility in cryptocurrency markets has always been a time-varying concept that changes over time. As opposed to the stock market, which has historically and recently, the cryptocurrency market is much more volatile. The markets have evidenced many fluctuations in the prices of cryptos. As a result, countries are transforming their policies to suit financial technologies in their economic practices. Blockchain technology allows people to obtain more benefits in a financial transaction and breaks hurdles in the financial system. The study has found no ARCH effect in BinanceCoin, BT Cash, Bitcoin, Vechain, and Zcash. It is discovered that there is an ARCH effect in the case of Ethereum, Tether, Tezos, and XRP. Whale cryptocurrencies have an ARCH effect. Daily closing prices of ten cryptocurrencies, including bitcoin, from January 1, 2019, to December 31, 2020, to determine the price volatility where the bitcoin whales hold significant cryptocurrency values. It has given significant results in case of volatility since we also found that Bitcoin's largest cryptocurrencies among the sample taken for the study have less volatility than other currencies. 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG. -
Cryptocurrency Market Anomaly: The Day-of-the-Week-Effect
Cryptocurrency has emerged as a fad amongst investors, academicians and policy-makers as a financial asset, making it important to empirically test the price behaviour of this emerging market. This paper is designed to investigate the presence of a well-known day-of-the-week effect in the young and emerging cryptocurrency market returns from August 2015 to March 2019. Using varied statistical techniques, this anomaly is examined for six cryptocurrencies (Bitcoin, Ethereum, Ripple, Litecoin, Stellar and Tether). The study applies both parametric and non-parametric statistical tests, i.e.,Bar Graph, Heat map, Students t-test, Analysis of Variance (ANOVA),regression analysis with dummy variables and the Kruskal Wallis Test. The studys findings show that no sample cryptocurrency returns exhibit the day-of-the-week effect phenomenon.The statistically insignificant result of the day-of-the-week effect in thecryptocurrency returns showcases the evidence of market efficiency in the cryptocurrency market. Indian Institute of Finance. -
Cryptocurrency Security and Privacy Issues: A Research Perspective
Cryptocurrency has developed as a new mode of money exchange since it has become easier, faster and safer. The first cryptocurrency was introduced in 2009 and since then, the growth rate of cryptocurrency has been increasing drastically. As of 2020, the cryptocurrency exchange all over the world has exceeded 300%. The researchers face many challenges during their research on the various cryptocurrencies. For example, most of the high-tech companies still do not support bitcoin on mobile platforms. High-tech companies like Google and Apple are also thinking into banning the bitcoin wallet from their app stores. The work provides a review of cryptocurrency and its types, scope on the investment plans and its advantages also discussed. The growth and comparison between bitcoins and gold is also discussed. The challenges researchers face and the security issues concerning it. This review provides an overview of how the different forms of cryptocurrency are increasing from over a decade. It explains the different types and the year in which they were invented. It also gives a brief comparison with respect to bitcoin, which is one of the most used cryptocurrency. Furthermore, it gives a brief explanation on investments, and schemes for those who are new in the cryptomarket. Later emphasizes on the security issues faced by this technology. It talks about proof of work and the different data attacks the software faced and how the issues were overcome. In the end, it talks about the challenges researchers face while researching cryptocurrency. 2021 IEEE. -
Cryptographic key distribution using artificial intelligence for data security and location privacy in VANET
Location privacy & data security in VANET are now becoming most important in todays paradigm of information age. Unauthorized access to location information of vehicles may pose a significant security threat, thus it is necessary to secure this information from intruders. In proposed work, Artificial intelligence based RF range approximation is used with multi key controlled cryptography for enhancement of location privacy and data security in service location protocol of VANETS. 2022 Taru Publications. -
Cryptographic Protocols for Securing Internet of Things (IoT)
Cryptographic protocols are used to relax the ever-developing quantity of linked gadgets that make up the net of things (IoT). Those cryptographic protocols have been designed to make certain that IoT tool traffic stays cozy and personal, even while nevertheless allowing tool-to-device and cloud-to-tool communications. Examples of these protocols consist of TLS/SSL, PGP/GPG, IPsec, SSL VPN, and AES encryption. Every one of these protocols enables authentication, message integrity, and confidentiality via encryption and key trade. Moreover, a lot of these protocols are carried out in the form of diverse hardware and software answers, such as smart playing cards and gateways, to make certain that IoT traffic is secured. With the appropriate implementation of those cryptographic protocols, establishments can ensure that their IoT facts are blanketed and securely transmitted. 2024 IEEE. -
Cryptography: Advances in Secure Communication and Data Protection
In the innovative work secure communication and data protection are being main field, which are emerged by cryptography as a fundamental pillar. Strong cryptographic methods are now essential given the rising reliance on digital technologies and the threats posed by bad actors. This abstract examines the evolution of secure communication protocols and data protection techniques as it relates to the advancements in cryptography. The development of post-quantum cryptography is the most notable development in cryptography discussed in this study. As quantum computers become more powerful, they pose a serious threat to traditional cryptographic algorithms, such as RSA and ECC. Designing algorithms that are immune to attacks from quantum computers is the goal of post-quantum cryptography. Lattice-based, code-based, and multivariate-based cryptography are only a few of the methods that have been investigated in this context. 2023 EDP Sciences. All rights reserved. -
Crystal and Molecular Structure of 1,1-Bis(methylthio)-5-(4-chlorophenyl)-1,4-pentadien-3-one
Journal of Crystallography, pp. 2014. -
Crystal shape engineering and studies on the performance of vapour deposited InSe platelets
The influence of growth conditions on the morphology of stoichiometric indium monoselenide (InSe) crystals has been explored. Crystalline habits such as microfibres, needles, platelets and spherulites were obtained from physical vapour deposition by optimizing supersaturation, which sturdily depends on the temperature difference between charge (TC) and substrate (TS) zones ?T, (= TC ? TS). Morphology and growth mechanism were investigated with the aid of scanning electron microscopy and high-resolution transmission electron microscopy, which justified the layer by layer addition of atoms as per the KosselStranskiVolmer model. Thermogravimetric measurements revealed the stability of InSe, confirming its melting point, M.P. = 611C, which reflects the formation of monophase. The mobility and carrier concentration calculated from the Hall effect experiment are found to be 11.14cm2V?1s?1 and 1.52 1020cm?3 respectively. Furthermore, optical characterizations such as UVVisNIR and photoluminescence spectrometric analysis established the value of band gap as 1.45eV, manifesting the versatility of the grown semiconducting platelets for photovoltaic applications. 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
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Crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3-dithiolan-2-ylidene)-1, 6-heptadiene-3,5-dione
The synthesis and crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound is a curcuminoid analogue, configurationally symmetric about the C4-C5 atoms and also retains the two fold axis in the crystal phase. This compound crystallizes in the space group C2/c with unit cell parameters a = 19.203(1) b = 13.147(1) c = 8.801(1) ? = 112.99(1), with half a molecule in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The push-pull nature of the ketenedithioacetal functionality organizes the cinnamoyl groups parallel to each other. 2008 Springer Science+Business Media, LLC. -
Crystal structure of 4-{(E)-[2-(pyridin-4-ylcarbonyl)hydrazin-1-ylidene]methyl}-phenyl acetate monohydrate
The asymmetric unit of the title compound, C15H13N3O3H2O, comprises a 4-{(E)-[2-(pyridin-4-ylcarbonyl)hydrazinyl-idene]methyl}phenyl acetate molecule and a solvent water molecule linked by O - H?O and O - H?N hydrogen bonds from the water molecule and a C - H?O contact from the organic molecule. The compound adopts an E conformation with respect to the azomethine bond and the dihedral angle between the pyridine and benzene rings is 21.90 (7). The azomethine bond [1.275 (2) distance is very close to the formal C=N bond length, which confirms the azomethine bond formation. An extensive set of O - H?O, O - H?N, N - H?O and C - H?O hydrogen bonds builds a two-dimensional network progressing along the c axis. -
Crystal structures of 1,7-bis(furyl)-4-(1,3-dithiolan-2-ylidene)-1, 6-heptadiene-3,5-dione and 1,7-bis(thienyl)-4-(1,3-dithiolan- 2-ylidene)-1,6-heptadiene-3,5-dione
The title compounds (bis(alkenoyl) ketene dithioacetals) were prepared starting from the cyclic acyl ketene dithioacetal and aromatic aldehydes. These compounds were characterized by IR, 1H NMR, mass spectral studies and X-ray crystal structure analysis. The bis(furyl) ketene dithioacetal crystallized in the space group P1? with unit cell dimensions a = 7.7626(12) , b = 9.0217(13) , c = 26.827(5) , ? = 86.271(14), ? = 87.643(14), ? = 66.286(11) and the structure was refined to an R-factor of 0.0528 while bis(thienyl) ketene dithioacetal crystallized in the space group P21/c with unit cell dimensions a = 10.2433(9) , b = 10.4142(6) , c = 18.0973(18) , ? = 106.0 and the structure was refined to an R-factor of 0.0446. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in these compounds. In both the crystal structures, the crystal packing is stabilized by C-H?O hydrogen bonds as well as van der Waals interactions. Springer Science+Business Media, LLC 2011. -
CSR as an agent of financial stability: A use case of banking industry
The study was undertaken to examine the importance of corporate social responsibility (CSR) as an agent to improve the firm's performance and financial stability by enhancing goodwill and competitive advantage in the Indian banking industry. In the study, it has been hypothesized that CSR expenses have a positive relationship with financial stability. A correlation study has also been undertaken to determine any relationship among these variables, followed by a dependency regression test to show the levels of dependency of financial stability on CSR expenses and the Granger Causality test to find their causal relationship. The study has revealed a significant relationship between the financial stability variables and CSR expenses, and the Granger Causality level supports the findings. 2021 Ecological Society of India. All rights reserved. -
CSR initiatives: A way of enhancing employees' wellbeing
Employees are seen as a valuable resource for assessing a business's competitiveness. Providing for their wellness, health, and running employee support programmes may increase their drive and commitment to the organization. This chapter will explain the role of CSR activities on employees' well-being, examine the impact of CSR activities on well-being of employees, and provide CSR strategies to maximize employees' well-being. A qualitative research technique was applied in this study. A systematic literature review was based on articles in national and international journals, magazines, working papers, etc. gathered and analyzed to achieve the research objective. The implementation of employees CSR activities has been significant, since employee health and wellness have a direct impact on the competitiveness of the business and have been a driving force behind employee's performance. 2024 by IGI Global. All rights reserved. -
Cu/Pd bimetallic supported on mesoporous TiO2 for suzuki coupling reaction
Generally bimetallic catalysts are more superior to monometallic catalysts and provide a better platform for the development of novel catalysts with enhanced activity, selectivity, and stability. In the current work we have prepared Cu/Pd bimetallic supported on mesoporous TiO2 by hydrothermal method. The prepared system was characterized by various physico-chemical techniques such as XRD, TG-DTG, SEM, EDAX, BJH isotherm, and XPS. Thermal stability and complete electronic structure were identified from TG and XPS measurements respectively. The bimetallic system was found to be very active in Suzuki cross-coupling reaction using different substrates. The products were separated and purified by column chromatography and the resultant products were characterized thoroughly by 1H NMR, and FT-IR analysis. Copyright 2018 BCREC Group. All rights reserved. -
Cu/Pd bimetallic supported on mesoporous TiO2 for suzuki coupling reaction /
Bulletin of Chemical Reaction Engineering & Catalysis, Vol.13, Issue 2, pp. 1-11, ISSN No. 1978-2993. -
Cubic spline curve public key cryptography
In this work, a cubic spline curve is considered for Asymmetric mode encrypting data. A Cubicspline curve is used to generate a set of points under initial known boundary conditions. This set of points is considered as generator points. Given the field, known the generator points, considering for some time and space steps and for a considered private key, Public key will be generated based on Discrete Logarithm problem. Thus for a set of public and private keys, data can be transmitted securely with features like Authenticity of users, Security & Confidentiality of data transmitted. Going by the construction of the algorithm, Encryption is being done on blocks of data for which it consumes less computing resources. Going by complexity of the algorithm, the key length needed is about 120 bit lengths to provide sufficient strengths against cryptoanalysis. 2017 Taru Publications. -
Cuda implementation of non-local means algorithm for GPU processors
Non-Local Means algorithm (NLM) is a prominent image denoising algorithm. One of the major limitations of NLM algorithm and its variants is the time requirement. In this era of high performance computing, an efficient alternative to reduce the time complexity of any algorithm is its parallelization. In this paper, a parallelized version of basic NLM algorithm using CUDA architecture is proposed. The algorithm is developed on NVIDIA GeForce 940M GPU which follows Maxwell architecture with 3 SMs and 384 CUDA cores. Experiments are carried out using selected set of natural and medical images of various sizes. Our proposed parallelized version of NLM algorithm reduces the time requirement approximately by 50% in comparison to its basic version and also achieves comparable denoising performance in terms of PSNR, SSIM and FSIM evaluation metrics. The proposal is a model which can be customized for newer GPU architectures. 2020, Engg Journals Publications. All rights reserved.