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ETP-AKEP: enhanced three-party authenticated key exchange protocols for data integrity in cloud environments

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Journal of control and Decision 2023年第1期10卷 126-133页

作者： Kalluri Rama Krishna c.v.Guru Rao Faculty of Informatics Osmania UniversityHyderabadIndia School of computer Science&Artificial Intelligence S.R.UniversityWarangalIndia

With key exchange protocols, a secure session key is generated between two remote users, andservers and exchanged between them. It is generally used to prevent unauthorised users fromgaining access to sensitive data. This article presents an enhanced three-party authenticated keyexchange protocols (ETP-AKE) protocol that does not depend on symmetric key encryption andinstead uses asymmetric key encryption. A key component of the proposed ETP-AKE protocol isusing elliptic curve encryption in conjunction with a one-way hash function. Its integrity certificationwas confirmed via the usage of the AvISPA tool package. Our proposed protocol is intendedto protect against various security threats, including the man-in-the-middle assault, the parallelattack, and the key-compromise attack, among others.

关键词： Ecc hash function cloud integrity third party key exchange

Petrology and geochemical characteristics of Precambrian granitic basement complex rocks in the southernmost part of North-central Nigeria

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chinese Journal Of Geochemistry 2009年第4期28卷 377-385页

作者： Obiora S.c. Ukaegbu v.U. National Geophysical Research Institute Geological Studies DivisionUppal Road Hyderabad-500007 India Department of Geology University of NigeriaNsukka Nigeria Department of Geology University of Port HarcourtPort Harcourt Nigeria

The Precambrian basement complex in the southernmost part of North-central Nigeria is underlain by migmatitic banded gneisses, granitic intrusions and dykes of dolerite, rhyolite porphyry and pegmatite. The rocks are generally felsic, containing modal and normative hypersthene, as well as normative corundum. The basement complex has experienced high-grade regional metamorphism as indicated by the presence of hypersthene and plagioclase of andesine composition. Anatectic melting is suggested by the occurrence of ptygmatic folds, folded gneissose foliation, numerous quartzo-feldspathic veins and lenses of dark-colured, micaceous schistose rocks. Geochemically, the rocks have magnesian, calc-alkalic and strongly peraluminous characteristics. Their overall characteristics suggest derivation from progressive (fractional) partial melting of pelitic rocks during high-grade regional metamorphism, possibly associated with intense hydrothermal activities. The magnesian characteristics reflect close affinity to relatively hydrous, oxidizing melts and source regions in settings broadly related to subduction.

关键词：岩石地球化学特征前寒武纪基底尼日利亚花岗岩中央区域变质作用流纹斑岩叶状结构

L-asparaginase production by mangrove derived Bacillus cereus MAB5:optimization by response surface methodology

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Asian Pacific Journal of Tropical Medicine 2011年第6期4卷 486-491页

作者： Thenmozhi c Sankar R Karuppiah v Sampathkumar P centre of Advanced Study in Marine Biology Faculty of Marine Sciences Annamalai University Parangipettai-608 502Tamil NaduIndia

Objective:To isolate marine bacteria,statistically optimize them for maximum asparaginase ***:In the present study,statistically based experimental designs were applied to maximize the production of L-asparaginase from bacterial strain of Bacillus cereus（***） MAB5（HQ675025） isolated and identified by 16S rDNA sequencing from mangroves rhizosphere ***:Plackett-Barman design was used to identify the interactive effect of the eight variables *** extract,soyabean meal,glucose,magnesium sulphate,KH2PO4,wood chips,aspargine and sodium *** the variables are denoted as numerical factors and investigated at two widely spaced intervals designated as -1（low level） and +1（high level）. The effect of individual parameters on L-asparaginase production was *** meal,aspargine,wood chips and sodium chloride were found to be the significant among eight *** maximum amount of L-asparaginase produced（51.54 IU/mL） from the optimized medium containing soyabean meal（6.282 8 g/L）,aspargine（5.5 g/L）,wood chips（1.383 8 g/L） and Nacl（4.535 4 g/L）.conclusions:The study revealed that,it is useful to produce the maximum amount of L-asparaginase from *** MAB5 for the treatment of various infections and diseases.

关键词： L-asparaginase Bacillus cereus Mangroves Plackett-Barman design central composite design

Neuroendocrine and squamous colonic composite carcinoma:case report with molecular analysis

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World Journal of Gastroenterology 2011年第42期17卷 4729-4733页

作者： Sabrina c Wentz cindy vnencak-Jones William v chopp Department of Pathology Vanderbilt University Medical Center Molecular Genetics Laboratory Vanderbilt University Medical Center Department of Pathology Veterans Affairs Medical Center

composite colorectal carcinomas are rare. There are amodest number of cases in the medical literature,with even fewer cases describing composite carcinoma with neuroendocrine and squamous components. There areto our knowledge no reports of composite carcinomamolecular alterations. We present a case of composite carcinoma of the splenic flexure in a 33 year-old cau-casian male to investigate the presence and prognos-tic significance of molecular alterations in rare coloniccarcinoma subtypes. Formalin-fixed paraffin-embedded(FFPE) tissue was hematoxylin and eosin- and mucicar-mine-stained according to protocol,and immuno-stained with cytokeratin(cK) 7,cK20,cDX2,AE1/AE3,chromo-granin-A and synaptophysin. DNA was extracted from FFPE tissues and molecular analyses were performed according to lab-developed methods,followed by capil-lary electrophoresis. Hematoxylin and eosin staining showed admixed neuroendocrine and keratinized squamous cells. Positive nuclear cDX2 expression confirme dintestinal derivation. cK7 and cK20 were *** cells stained positively for synaptophysin and AE1/AE3 and negatively for chromogranin and mucicarmine. Hepatic metastases showed a similar immunohistochemical profile. Molecular analysis revealeda G13D KRAS mutation. BRAF mutational testing wasnegative and microsatellite instability was not *** patient had rapid disease progression on chemotherapy and died 60 d after presentation. Although theG13D KRAS mutation normally predicts an intermed iateoutcome,the aggressive tumor behavior suggests other modifying factors in rare types of colonic carcinomas.

关键词： composite carcinoma Neuroendocrine Squamous KRAS BRAF Microsatellite instability

characteristic Study of the Boundary Layer Parameters over the Arabian Sea and the Bay of Bengal Using the QuikScAT Dataset

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Advances in Atmospheric Sciences 2007年第4期24卷 631-643页

作者： v.HAMZA c.A.BABU T.P.SABIN Department of Atmospheric Sciences Cochin University of Science and TechnologyCochin-682 016India

The marine atmospheric boundary layer （MABL） plays a vital role in the transport of momentum and heat from the surface of the ocean into the atmosphere. A detailed study on the MABL characteristics was carried out using high-resolution surface-wind data as measured by the QuikScAT （Quick scatterometer） satellite. Spatial variations in the surface wind, frictional velocity, roughness parameter and drag coefficient for the different seasons were studied. The surface wind was strong during the southwest monsoon season due to the modulation induced by the Low Level Jetstream. The drag coefficient was larger during this season, due to the strong winds and was lower during the winter months. The spatial variations in the frictional velocity over the seas was small during the post-monsoon season （-0.2 m s^-1）. The maximum spatial variation in the frictional velocity was found over the south Arabian Sea （0.3 to 0.5 m s^-1） during the southwest monsoon period, followed by the pre-monsoon over the Bay of Bengal （0.1 to 0.25 m s^-1）. The mean wind-stress curl during the winter was positive over the equatorial region, with a maximum value of 1.5×10^-7 N m^-3, but on either side of the equatorial belt, a negative wind-stress curl dominated. The area average of the frictional velocity and drag coefficient over the Arabian Sea and Bay of Bengal were also studied. The values of frictional velocity shows a variability that is similar to the intraseasonal oscillation （ISO） and this was confirmed via wavelet analysis. In the case of the drag coefficient, the prominent oscillations were ISO and quasi-biweekly mode （QBM）. The interrelationship between the drag coefficient and the frictional velocity with wind speed in both the Arabian Sea and the Bay of Bengal was also studied.

关键词： boundary layer characteristics drag coefficient frictional velocity roughness length QuikScAT wind

Early Growth Response gene 1 (Egr-1) regulates HSv-1 IcP4 and IcP22 gene expression

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cell Research 2007年第6期17卷 546-555页

作者： Gautam R Bedadala Rajeswara c Pinnoji Shao-chung v Hsia Department of Basic Pharmaceutical Sciences College of Pharmacy The University of Louisiana at Monroe 700 University AvenueMonroeLA 71209 USA

The molecular mechanisms mediating herpes simplex virus type 1 (HSv-1) gene silencing during latent infection arenot clear. Five copies of early growth response gene 1 (Egr-1) binding elements were identified in the intron of HSv-1IcP22 (infected cell protein No. 22) gene, leading to the hypothesis that Egr-1 binds to the viral genome and regulates theviral gene expression. Transient co-transfection assays indicated that Egr-1 negatively regulated the transcription of bothfull-length and intron-removed IcP22 promoters. The same assays also revealed that Egr-1 repressed IcP4 (infected cellprotein No. 4) promoter activity in a dose-dependent manner but showed less inhibition when the intron was *** deacetylation was not involved in this regulation since histone deacetylase inhibitor trichostatin Adid not exhibitany effect on Egr-1-mediated repression. chromatin immunoprecipitation assays showed that Egr-1 reduced the bindingof Spl to the promoters and that the co-repressor Nab2 (NGFI-A/EGR1-binding protein) was recruited to the proximityof IcP4 in the presence of Egr-1. These results suggested that the multifunctional transcription factor Egr-1 can repressHSv-1 immediate-early gene expression through the recruitment of co-repressor Nab2 and reduction of Sp1 occupancy,and thus may play a critical role in HSv-1 gene silencing during latency.

关键词： HSv-1 latency Egr-1 Sp1 Nab2 transcription regulation

Spectroscopy of a Gamma Irradiated Poly(Acrylic Acid)-clotrimazole System

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chinese Physics Letters 2011年第12期28卷 274-277页

作者： M.Todica c.v.Pop Luciana Udrescu Traian Stefan Faculty of Physics Babes-Bolyai University400084 Cluj-NapocaRomania

A poly(acrylic acid)-clotrimazole system,gamma irradiated at different doses,is investigated by Raman *** of the spectrum of the polymeric matrix appear for doses of radiation greater than 333 Gy,whereas the spectrum of clotrimazole remains unaffected at these doses of *** changes correlate with modification of the vibration modes of cOOH and cH_(2) groups of a polymeric matrix after irradiation.

关键词： spectroscopy polymeric matrix

Sea Urchin Spines as a Model-System for Permeable,Light-Weight ceramics with Graceful Failure Behavior. Part I. Mechanical Behavior of Sea Urchin Spines under compression

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Journal of Bionic Engineering 2009年第4期6卷 203-213页

作者： v.Presser S.SchultheiB c.Berthold K.GNickel Institute

The spines of pencil and lance urchins Heterocentrotus mammillatus and Phyllacanthus imperialis were studied as a model of light-weight material with high impact *** complex and variable skeleton construction ('stereom') of body and spines of sea urchins consists of highly porous Mg-bearing calcium *** basically brittle material with pronounced single-crystal cleavage does not fracture by spontaneous catastrophic device failure but by graceful failure over the range of tens of millimeter of bulk compression *** was observed in bulk compression tests and blunt indentation experiments on regular,infiltrated and latex coated sea urchin spine *** characterization was carried out using X-ray computer tomography,optical and scanning electron *** behavior is interpreted to result from the hierarchic structure of sea urchin spines from the rnacroscale down to the *** derived from this study see ceramics with layered porosity as a possible biomimetic construction for appropriate applications.

关键词： sea urchin urchin spines biominmitic mechanical behavior compression calcite

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Microstructures and mechanical properties of nanocrystalline NiTi intermetallics formed by mechanosynthesis

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 80-87页

作者： S.Arunkumar P.Kumaravel c.velmurugan v.Senthilkumar vinayaka Mission's Kimpananda variyar Engineering college Salem 636308TamilnaduIndia Institute of Road and Transport Technology Erode 638316TamilnaduIndia National Institute of Technology Trichy 620015TamilnaduIndia

The formulation of nanocrystallinc NiTi shape memory alloys has potential effects in mechanical stimulation and medical im- plantology. The present work elucidates the effect of milling time on the product＇s structural characteristics, chemical composition, and mi- crohardness for NiTi synthesized by mechanical alloying for different milling durations. Increasing the milling duration led to the formation of a nanocrystalline NiTi intermetallic at a higher level. The formation of nanocrystalline materials was directed through cold fusion, fractur- ing, and the development of a steady state, which were influenced by the accumulation of strain energy. In the morphological study, uninter- rupted cold diffusion and fracturing were visualized using transmission electron microscopy. Particle size analysis revealed that the mean particle size was reduced to -93 μm after 20 h of milling. The mechanical strength was enhanced by the formation of a nanocrystalline in- termetallic phase at longer milling time, which was confirmed by the results of vickers hardness analyses.

关键词： nickel-titanium shape memory alloy lattice strain nano-crystalline mechanical alloying microstructural characterization