Improvement in short-circuited coaxial flange for evaluating microwave superconducting properties at low temperature

5-10In the present study, we have proposed an improvement in terms of the determination of S-parameters of an open flange from its characteristic impedance and propagation constant. With the help of these S-parameters, the actual reflection coefficient of YBCO films deposited on LAO substrate is obtained from the measured reflection coefficient. The surface impedance of three YBCO films is obtained in the range of few ohms in the frequency range from 1 GHz to 40 GHz. The surface resistance of the films reduces at liquid nitrogen temperature, i.e., 77 K, whereas, the surface reactance slightly increases due to kinetic inductance. The conductivity and skin depth are also determined to validate the improvement in the method

Improvement in short-circuited coaxial flange for evaluating microwave superconducting properties at low temperature

In the present study, we have proposed an improvement in terms of the determination of S-parameters of an open flange from its characteristic impedance and propagation constant. With the help of these S-parameters, the actual reflection coefficient of YBCO films deposited on LAO substrate is obtained from the measured reflection coefficient. The surface impedance of three YBCO films is obtained in the range of few ohms in the frequency range from 1 GHz to 40 GHz. The surface resistance of the films reduces at liquid nitrogen temperature, i.e., 77 K, whereas, the surface reactance slightly increases due to kinetic inductance. The conductivity and skin depth are also determined to validate the improvement in the method

A simple method to estimate the loading effects of Al/Si on the characteristic impedance of multilayer microstrip line

The present study aims to experimentally determine the microwave transmission and reflection properties of aluminum thin film grown on silicon using sputtering. A simple microstrip line based structure has been used for the microwave characterization in the frequency range 10 MHz to 26.5 GHz. Complex S-parameter measurements reveal only small differences on silicon loading and aluminum/silicon loading in comparison to the microstrip line. The characteristic impedance (Z) of the microstrip line loaded with silicon and with aluminum/silicon have been obtained corresponding to the length of the loadings using two port microwave analysis. Comparison of loaded microstrip line with no loading shows large changes in the real part well as imaginary part of the characteristic impedance in the frequency range less than 10 GHz. Percentage changes in the real (Z) and imaginary (Z) have been found as ± 40% and ± 10% in average, respectively, for silicon loading in comparison to the no loading case, whereas these changes have been found to be below ±5% for aluminium/silicon loading, thus these smaller changes suggest the similar responses for aluminium/silicon loading and no loading. The results reveal that the propagation can be restored with the application of aluminum with any semiconductor or dielectric as loading on the microstrip line, which shows its potential to be explored for making an individual microwave component

Distribution and sources of polychlorinated biphenyls in air, dust and sediment from India

Persistent organic pollutants, such as polychlorinated biphenyls (PCBs), pose a serious risk for human health and the environment. In this study, PCBs contamination and sources of ambient air, road dust, and sediments in the most polluted city in India, Raipur, has been measured over the period 2008–2015. The seasonal variations of particulate matter (PM), elemental carbon (EC), organic carbon (OC), and carbonate carbon (CC) were studied, and maximum concentrations were detected in the December–January period each year. Total PCBs concentrations in the ambient air (associated with PM), road dust, and sediments samples during 2008 were in the 186–645 pg m−3, 102–537, and 241–538 ng g−1 range, respectively. 2-chlorobiphenyl (PCB-1) and 4-chlorobiphenyl (PCB-3) were the dominant chemical compounds identified. A substantial vertical migration of the PCBs in the sediments was observed. Concentration variations (spatial and temporal), correlations, and sources of PCB are discussed. In particular, an average increment rate of 6.2%, 4.9%, and 5.4% of PCBs concentration in the particulate matter (PM10), road dust, and sediments, respectively, was observed over the 2008–2015 period. The reported data points to India's low degree of accomplishment of the Stockholm Convention's requirement to phase out the use of PCBs in equipment by 2025 and ensure elimination of PCBs by 2028

Potential Development of N-Doped Carbon Dots and Metal-Oxide Carbon Dot Composites for Chemical and Biosensing

Funding Information: The authors are would like to thank the Department of Chemistry, Government VYT PG Autonomous College Durg, Chhattisgarh, sponsored by DST-FIST (New Delhi), India and the Fundação para a Ciência e a Tecnologia (FCT), Portugal, for the Scientific Employment Stimulus-Institutional Call (CEEC-INST/00102/2018) and the Associate Laboratory for Green Chemistry-LAQV, financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/5006/2020). Publisher Copyright: © 2022 by the authors.Among carbon-based nanomaterials, carbon dots (CDs) have received a surge of interest in recent years due to their attractive features such as tunable photoluminescence, cost effectiveness, nontoxic renewable resources, quick and direct reactions, chemical and superior water solubility, good cell-membrane permeability, and simple operation. CDs and their composites have a large potential for sensing contaminants present in physical systems such as water resources as well as biological systems. Tuning the properties of CDs is a very important subject. This review discusses in detail heteroatom doping (N-doped CDs, N-CDs) and the formation of metal-based CD nanocomposites using a combination of matrices, such as metals and metal oxides. The properties of N-CDs and metal-based CDs nanocomposites, their syntheses, and applications in both chemical sensing and biosensing are reviewed.publishersversionpublishe

Aromatic Stacking Facilitated Self-Assembly of Ultrashort Ionic Complementary Peptide Sequence: β-Sheet Nanofibers with Remarkable Gelation and Interfacial Properties

Understanding peptide self-assembly mechanisms and stability of the formed assemblies is crucial for development of functional nanomaterials. Herein, we have adopted rational design approach to demonstrate how minimal structural modification to a non-assembling ultra-short ionic self-complementary tetrapeptide FEFK (Phe4) remarkably enhanced stability of self-assembly into β-sheet nanofibres and induced hydrogelation. This was achieved by replacing flexible phenylalanine residue (F) by the rigid phenylglycine (Phg) resulting in constrained analogue PhgEPhgK (Phg4), which positioned aromatic rings in an orientation favourable for aromatic stacking. Phg4 self-assembly into stable β-sheet ladders was facilitated by π-staking of aromatic sidechains alongside hydrogen bonding between backbone amides along the nanofibre axis. The contribution of these non-covalent interactions in stabilising self-assembly was predicted by in silico modelling using molecular dynamics simulations and semi-empirical quantum mechanics calculations. In aqueous medium, Phg4 β-sheet nanofibres entangled at a critical gelation concentration > 20 mg/mL forming a network of nanofibrous hydrogel. Phg4 also demonstrated unique surface activity in presence of immiscible oils and was superior to commercial emulsifiers in stabilising oil-in-water emulsions. This was attributed to interfacial adsorption of amphiphilic nanofibrilles forming nanofibrillised microspheres. To our knowledge, Phg4 is the shortest ionic self-complementary peptide rationally designed to self-assemble into stable β-sheet nanofibres capable of gelation and emulsification. Our results suggest that Ultra-short Ionic-complementary Constrained Peptides or UICPs have significant potential for the development of cost-effective, sustainable and multifunctional soft bionanomaterials

Mechanisms of novel Hsp70 inhibitors and the co-chaperone Hsp110

Hsp70 is a ubiquitously expressed molecular chaperone and required for maintaining protein homeostasis. Hsp70 is also highly upregulated in many cancer cells and important for their survival. Therefore, small molecule inhibitors are being developed for clinical use. Of those that are available currently, most, if not all, have poor potency, specificity or off-target effects. Thus, there is a need for specific Hsp70 inhibitors. Our collaborators developed a novel inhibitor of Hsp70 called YK5 (YK-series), which was effective at killing cancer cells. YK5 interacts with an allosteric interaction site which contains a cysteine residue where it binds covalently. I established a cellular assay for the Hsp70-mediated protein folding and solubilization and show that YK5 indeed disrupts the core biochemical functions of Hsp70. Hsp70 is an ATP-dependent molecular chaperone with a cycle that requires an ATPase stimulating DNAJ protein and a nucleotide exchange factor, NEF, to displace ADP. These changes in the nucleotide state in the nucleotide-binding domain drive the conformational changes in the substrate-binding domain. In the ATP-bound state, Hsp70 does not bind substrate, whereas in the ADP or apo-state, it does. Understanding how the YK inhibitors affect Hsp70 is important, especially when using them as tools to study biological functions of Hsp70. I show that the reversible analog of YK5, 17l, increases peptide binding to Hsc70 and Hsp70 in the core ATPase cycle. The effects are on the kinetics of substrate release, but also for Hsc70 in the equilibrium between substrate free and bound states. However, with the NEF Hsp110 present in the cycle, peptide binding to Hsc70 and Hsp70 decreases due to faster dissociation of Hsp110 caused by 17l. In both cases, there is a disruption of the ATPase cycle, which affects the ability of the Hsp70s to fold and solubilize substrate, an effect we observed in cells. The mechanistic effects of 17l on substrate interaction suggested the importance of the Hsp70 chaperone complex, as a whole, specifically with Hsp110. First, I show that Hsp110 is indeed important for folding and solubilization of substrate in cells and cannot be substituted by the Bag family of NEFs. I specifically addressed the importance of the Hsp70-Hsp110 interaction by designing a mutant of Hsp70 predicted to lose interaction with Hsp110; Hsp70-R301E. With this mutant, I show the first direct evidence for the importance of this interaction for folding and solubilization of substrate by Hsp70 in cells. I then show that the disaggregation of a mutant implicated in amyotrophic lateral sclerosis, SOD1-G85R, is dependent on a mechanism involving Hsp70 and Hsp110. Overall, this work demonstrates the direct importance of the Hsp70-Hsp110 interaction in cells for Hsp70 chaperoning functions.Hsp70 est un chaperon moléculaire exprimé ubiquiteusement et nécessaire au maintien de l'homéostasie des protéines. Hsp70 est également régulé à la hausse dans plusieures des cellules cancéreuses et important pour leur survie. C'est pourquoi des petites molécules inhibitrices sont en développement pour une utilisation clinique. La quasi-totalité de ces inhibiteurs disponibles à ce jour ont une activité et spécificité très basse et ont des effets non-ciblés. C'est pourquoi il y a un besoin d'inhibiteurs spécifiques de Hsp70. Nos collaborateurs ont développé un nouvel inhibiteur de Hsp70; YK5 (série YK) qui s'est avéré être efficace à tuer des cellules cancéreuses. YK5 interagit en se liant d'une manière covalente au résidu cystéine d'un site allostérique. J'ai établi un test cellulaire de pliage et de solubilisation des agrégats protéique (les deux dépendant de Hsp70) et j'ai démontré que YK5 perturbe en effet les fonctions biochimiques essentielles de Hsp70. Hsp70 est un chaperon moléculaire qui dépend de l'ATP et qui nécessite la protéine DNAJ (qui stimule l'ATPase) ainsi que le facteur d'échange de nucléotides NEF, pour déloger l'ADP. Ces changements de nucléotide dans le domaine de liaison de nucléotides entraînent les changements conformationnels du domaine de liaison du substrat. Dans son état de liaison avec l'ATP, Hsp70 ne se lie pas à un substrat tandis que dans l'état de liaison avec l'ADP ou l'état-apo il se lie à un substrat. La compréhension du mécanisme par lequel les inhibiteurs YK affectent Hsp70 est importante, surtout dans le contexte de leur utilisation comme des outils moléculaires pour l'étude des fonctions biologiques de Hsp70. Je démontre que l'analogue réversible de YK5, 171, augmente la liaison du peptide à Hsc70 et à Hsp70 dans le cœur du cycle de l'ATPase. Les effets sont dûs à la cinétique de la libération du substrat, mais également, pour Hsc70, à l'équilibre entre les états de substrat libre et de substrat lié. Par contre, avec le NEF Hsp110 présent dans le cycle, la liaison du peptide avec Hsc70 et Hsp70 diminue en conséquence de la dissociation plus rapide de Hsp110 causé par 171. Dans les deux cas, il y a perturbation du cycle de l'ATPase, ce qui affecte la capacité des Hsp70s à plier et solubiliser le substrat, un effet observable dans les cellules. Les effets mécanistiques de 171 sur l'interaction avec le substrat suggéraient l'importance du complexe chaperon Hsp70, dans son entièreté, spécifiquement en conjonction avec Hsp110. Premièrement, je démontre que Hsp110 est en effet important pour le pliage et la solubilisation du substrat dans les cellules et ne peut être substitué par la famille BAG des NEFs. J'ai spécifiquement adressé l'importance de l'interaction Hsp70-Hsp110 en produisant un mutant de Hsp70 conçu pour perdre l'interaction avec Hsp110; Hsp70-R301E. Avec ce mutant je démontre la toute première preuve directe de l'importance de cette interaction pour le pliage et la solubilisation du substrat par Hsp70 dans les cellules. Par la suite, je démontre que la désagrégation du mutant SOD1-G85R, qui est impliqué dans la sclérose amyotropique latérale, est dépendante d'un méchanisme qui implique Hsp70 et Hsp110. Dans son ensemble, mon travail démontre l'importance directe de l'intéraction Hsp70-Hsp110 pour les fonctions cellulaires de chaperon de Hsp70

FINGERPRINT DETECTION AND RECOGNIZATION TECHNIQUES USING GABOR FILTER

Fingerprints are most extensively and effectively appropriate for the proof of identity in present days. Mostly because of their uniqueness among the people, public acceptance, originality, stability through life, and their least risk of invasion. Fingerprint technology, which is basically a biometric system, is utilized to identify an individual based on their physical qualities. Fingerprint matching is the trendiest biometric method appropriate to provide authentication. Fingerprint verification is one of the most trustable biometric security system in the world of computers. In this paper we proposed fingerprint algorithm which uses Gabor filter to capture local and global minute details in a fingerprint. The matching is based Euclidean distance between input image to test compared to trained fingerprints images. We are able to detect fingerprint with marginally best results. Our fingerprint framework performs best as compared to any other techniques

A simple method to estimate the loading effects of Al/Si on the characteristic impedance of multilayer microstrip line

959-964The present study aims to experimentally determine the microwave transmission and reflection properties of aluminum thin film grown on silicon using sputtering. A simple microstrip line based structure has been used for the microwave characterization in the frequency range 10 MHz to 26.5 GHz. Complex S-parameter measurements reveal only small differences on silicon loading and aluminum/silicon loading in comparison to the microstrip line. The characteristic impedance (Z) of the microstrip line loaded with silicon and with aluminum/silicon have been obtained corresponding to the length of the loadings using two port microwave analysis. Comparison of loaded microstrip line with no loading shows large changes in the real part well as imaginary part of the characteristic impedance in the frequency range less than 10 GHz. Percentage changes in the real (Z) and imaginary (Z) have been found as ± 40% and ± 10% in average, respectively, for silicon loading in comparison to the no loading case, whereas these changes have been found to be below ±5% for aluminium/silicon loading, thus these smaller changes suggest the similar responses for aluminium/silicon loading and no loading. The results reveal that the propagation can be restored with the application of aluminum with any semiconductor or dielectric as loading on the microstrip line, which shows its potential to be explored for making an individual microwave component