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A modularized electronic payment system for agent-based e-commerce
With the explosive growth of the Internet, electronic-commerce (e-commerce) is an increasingly important segment of commercial activities on the web. The Secure Agent Fabrication, Evolution & Roaming (SAFER) architecture was proposed to further facilitate e-commerce using agent technology. In this paper, the electronic payment aspect of SAFER will be explored. The Secure Electronic Transaction (SET) protocol and E-Cash were selected as the bases for the electronic payment system implementation. The various modules of the payment system and how they interface with each other are shown. An extensible implementation done using JavaTM will also be elaborated. This application incorporates agent roaming functionality and the ability to conduct e-commerce transactions and carry out intelligent e-payment procedures
Synthesis and photophysical studies on 5-ethoxycarbonyl-4-cinnamyl-6-methyl- 3,4-dihydropyrimidine-2(1H)-one in various solvents
The 5-ethoxycarbonyl-4-cinnamyl-6-methyl-3,4-dihydropyrimidine-2(1H)-one (DHPM) was synthesized via Biginelli reaction and was characterized by NMR, IR, UV–Visible absorption and fluorescencespectroscopy. The fluorescence of the compound exhibits red shift from its absorption spectra and correlated with the solvent polarity. The quantum yield of fluorescence of the DHPM was found to vary with solvent polarity. The absorption spectrum of DHPM overlaps significantly with anthracene fluorescence spectrum. Therefore fluorescence quenching experiments were performed in 1,4-dioxane. The fluorescence of anthracene was found to be quenched and quenching is in accordance with Stern-Volmer relation. The Stern-Volmer constant (KSV = 2.52 x 103 M-1) was obtained. The quenching rate constant (kq = 7.145 x 1011 M-1 s-1) was calculated from the fluorescence lifetime of anthracene measured on time resolved fluorimeter (TRF) in absence of DHPM. The fluorescence quenching explained on the basis of energy transfer from anthracene to DHPM derivative. The rate constant as well as efficiency of energy transfer depends on the distance between donor and acceptor and found to be r = 6.39 nm which indicates energy transfer
A plasmonic nanosensor with inverse sensitivity for circulating cell-free DNA quantification
A plasmonic nanosensor (using gold nanorods) with inverse sensitivity is presented for circulating cell-free DNA quantification. The inverse sensitivity (i.e. the lower the analyte concentration, the higher the response intensity) is achieved by the unusual DNA concentration-dependent gold nanorod aggregation. This assay method can adjust the dynamic range by controlling the concentration of nanoparticles in solution.
Graphical abstract: A plasmonic nanosensor with inverse sensitivity for circulating cell-free DNA quantificatio
Determination of the tension softening curve of nuclear graphites using the incremental displacement collocation method
postprin
Continuous variable quantum key distribution with two-mode squeezed states
Quantum key distribution (QKD) enables two remote parties to grow a shared
key which they can use for unconditionally secure communication [1]. The
applicable distance of a QKD protocol depends on the loss and the excess noise
of the connecting quantum channel [2-10]. Several QKD schemes based on coherent
states and continuous variable (CV) measurements are resilient to high loss in
the channel, but strongly affected by small amounts of channel excess noise
[2-6]. Here we propose and experimentally address a CV QKD protocol which uses
fragile squeezed states combined with a large coherent modulation to greatly
enhance the robustness to channel noise. As a proof of principle we
experimentally demonstrate that the resulting QKD protocol can tolerate more
noise than the benchmark set by the ideal CV coherent state protocol. Our
scheme represents a very promising avenue for extending the distance for which
secure communication is possible.Comment: 8 pages, 5 figure
Exploring the diverse definitions of ‘evidence’: a scoping review
OBJECTIVES:
To systematically collect and analyse diverse definitions of ‘evidence’ in both health and social sciences, and help users to correctly use the term ‘evidence’ and rethink what is the definition of ‘evidence’ in scientific research.
DESIGN:
Scoping review.
METHODS:
Definitions of evidence in the health sciences and social sciences were included. We have excluded the definition of evidence applied in the legal field, abstracts without full text, documents not published in either Chinese or English and so on. We established a multidisciplinary working group and systematically searched five electronic databases including Medline, Web of Science, EBSCO, the Chinese Social Sciences Citation Index and the Chinese Science Citation Database from their inception to 26 February 2022. We also searched websites and reviewed the reference lists of the identified studies. Six reviewers working in pairs, independently, selected studies according to the inclusion and exclusion criteria, and extracted information. Any differences were discussed in pairs, and if there was disagreement, it was resolved via discussion or with the help of a third reviewer. Reviewers extracted document characteristics, the original content for the definitions of ‘evidence’, assessed definitions as either intensional or extensional, and any citations for the given definition.
RESULTS:
Forty-nine documents were finally included after screening, and 68 definitions were obtained. After excluding duplicates, a total of 54 different definitions of ‘evidence’ were identified. There were 42 intensional definitions and 12 extensional definitions. The top three definiens were ‘information’, ‘fact’ and ‘research/study’. The definition of ‘evidence’ differed between health and social sciences. The term ‘research’ appeared most frequently in the definitions.
CONCLUSIONS:
The definition of ‘evidence’ has gradually attracted the attention of many scholars and decision-makers in health and social sciences. Nevertheless, there is no widely recognised and accepted definition in scientific research. Given the wide use of the term, we need to think about whether, or under what circumstances, a standardised, clear, meaningful and widely applicable definition of ‘evidence’ might be helpful
Preliminary Results on Evaluation of Chickpea, Cicer arietinum, Genotypes for Resistance to the Pulse Beetle, Callosobruchus maculatus
The chickpea, Cicer arietinum L. (Fabales: Fabaceae), seeds are vulnerable, both in the field and in storage, to attack by seed-beetles. Beetles of the genus Callosobruchus are major storage pests of chickpea crops and cause considerable economic losses. In the present study, a total of 11 chickpea genotypes including five ‘kabuli’ (Mexican white, Diyar, CA 2969, ILC 8617 and ACC 245) and six ‘desi’ chickpeas (ICC 1069, ICC 12422, ICC 14336, ICC 4957, ICC 4969 and ICC 7509) were evaluated for resistance to the pulse beetle Callosobruchus maculatus F. (Coleoptera: Bruchidae). Resistance was evaluated by measuring percent damage to seeds. Damage to seeds by C. maculatus was manifested by the round exit holes with the ‘flap’ of seed coat made by emerging adults. Of the 11 genotypes tested, only one (ICC 4969) exhibited a complete resistance to C. maculatus in both free-choice and no-choice tests; no seed damage was found over the test period. In general, the ‘desi’ chickpeas were more resistant to C. maculatus than the ‘kabuli’ chickpeas. Among the tested chickpea genotypes, only ICC 4969 can be used as a source of C. maculatus resistance in breeding programmes that could then be grown in organic cultivation free from pesticides
Rheumatoid arthritis patients exhibit impaired Candida albicans-specific Th17 responses
Introduction: Accumulating data implicate the CD4+ T cell subset (Th17 cells) in rheumatoid arthritis (RA). IL-17 is an inflammatory cytokine that induces tumor necrosis factor (TNF)α, IL-1β and IL-6, all of which are targets of biologic therapies used to treat RA. RA patients are well documented to experience more infections than age-matched controls, and biologic therapies further increase the risk of infection. The Th17/IL-17 axis is vital for immunity to fungi, especially the commensal fungus Candida albicans. Therefore, we were prompted to examine the relationship between RA and susceptibility to C. albicans because of the increasing interest in Th17 cells and IL-17 in driving autoimmunity, and the advent of new biologics that target this pathway.Methods: We analyzed peripheral blood and saliva from 48 RA and 33 healthy control subjects. To assess C. albicans-specific Th17 responses, PBMCs were co-cultured with heat-killed C. albicans extract, and IL-17A levels in conditioned supernatants were measured by ELISA. The frequency of Th17 and Th1 cells was determined by flow cytometry. As a measure of IL-17A-mediated effector responses, we evaluated C. albicans colonization rates in the oral cavity, salivary fungicidal activity and levels of the antimicrobial peptide β-defensin 2 (BD2) in saliva.Results: Compared to controls, PBMCs from RA subjects exhibited elevated baseline production of IL-17A (P = 0.004), although they had similar capacity to produce IL-17A in response to Th17 cell differentiating cytokines (P = 0.91). However RA PBMCs secreted less IL-17A in response to C. albicans antigens (P = 0.006). Significantly more RA patients were colonized with C. albicans in the oral cavity than healthy subjects (P = 0.02). Concomitantly, RA saliva had reduced concentrations of salivary BD2 (P = 0.02). Nonetheless, salivary fungicidal activity was preserved in RA subjects (P = 0.70).Conclusions: RA subjects exhibit detectable impairments in oral immune responses to C. albicans, a strongly Th17-dependent opportunistic pathogen, despite an overall elevated baseline production of IL-17A. © 2014 Bishu et al.; licensee BioMed Central Ltd
Ictal asystole secondary to suspected herpes simplex encephalitis: a case report
Herpes simplex virus is a leading cause of sporadic encephalitis. While seizures are a common feature of Herpes simplex virus encephalitis, and periods of asystole have been reported in Herpes simplex virus patients, there have been no prior reports of ictal asystole secondary to such an infection
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