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11.
Electronic documents used in the framework of the goods delivery industry—i.e. electronic bills of lading (e-BOLs)—are the enablers of any payment, and therefore exposed to frauds. As of today, e-BOLs are handled by special private companies, which provide paperless trading services through their trade chains. This paper contributes a zero-knowledge open solution to the problem of designing secure electronic bills of lading, in the framework of a shipper-carrier-buyer transmission model. The suggested solution is a cryptographic protocol based on digital signatures and blind merchandise counts—that is, counts that do not reveal any information about actually counted quantities. The model is designed to mitigate a number of security threats and assumes the existence of both a trusted third party and a bank in charge of payment procedures. The paper discusses the drawbacks of the existing proprietary solutions and shows how the suggested open protocol addresses them. 相似文献
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Mikhail G. Akimov Alina M. Gamisonia Polina V. Dudina Natalia M. Gretskaya Anastasia A. Gaydaryova Andrey S. Kuznetsov Galina N. Zinchenko Vladimir V. Bezuglov 《International journal of molecular sciences》2021,22(2)
GPR55 is a GPCR of the non-CB1/CB2 cannabinoid receptor family, which is activated by lysophosphatidylinositol (LPI) and stimulates the proliferation of cancer cells. Anandamide, a bioactive lipid endocannabinoid, acts as a biased agonist of GPR55 and induces cancer cell death, but is unstable and psychoactive. We hypothesized that other endocannabinoids and structurally similar compounds, which are more hydrolytically stable, could also induce cancer cell death via GPR55 activation. We chemically synthesized and tested a set of fatty acid amides and esters for cell death induction via GPR55 activation. The most active compounds appeared to be N-acyl dopamines, especially N-docosahexaenoyl dopamine (DHA-DA). Using a panel of cancer cell lines and a set of receptor and intracellular signal transduction machinery inhibitors together with cell viability, Ca2+, NO, ROS (reactive oxygen species) and gene expression measurement, we showed for the first time that for these compounds, the mechanism of cell death induction differed from that published for anandamide and included neuronal nitric oxide synthase (nNOS) overstimulation with concomitant oxidative stress induction. The combination of DHA-DA with LPI, which normally stimulates cancer proliferation and is increased in cancer setting, had an increased cytotoxicity for the cancer cells indicating a therapeutic potential. 相似文献
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Anastasia V. Ponasenko Maria V. Khutornaya Anton G. Kutikhin Natalia V. Rutkovskaya Anna V. Tsepokina Natalia V. Kondyukova Arseniy E. Yuzhalin Leonid S. Barbarash 《International journal of molecular sciences》2016,17(9)
Severe bioprosthetic mitral valve calcification is a significant problem in cardiovascular surgery. Unfortunately, clinical markers did not demonstrate efficacy in prediction of severe bioprosthetic mitral valve calcification. Here, we examined whether a genomics-based approach is efficient in predicting the risk of severe bioprosthetic mitral valve calcification. A total of 124 consecutive Russian patients who underwent mitral valve replacement surgery were recruited. We investigated the associations of the inherited variation in innate immunity, lipid metabolism and calcium metabolism genes with severe bioprosthetic mitral valve calcification. Genotyping was conducted utilizing the TaqMan assay. Eight gene polymorphisms were significantly associated with severe bioprosthetic mitral valve calcification and were therefore included into stepwise logistic regression which identified male gender, the T/T genotype of the rs3775073 polymorphism within the TLR6 gene, the C/T genotype of the rs2229238 polymorphism within the IL6R gene, and the A/A genotype of the rs10455872 polymorphism within the LPA gene as independent predictors of severe bioprosthetic mitral valve calcification. The developed genomics-based model had fair predictive value with area under the receiver operating characteristic (ROC) curve of 0.73. In conclusion, our genomics-based approach is efficient for the prediction of severe bioprosthetic mitral valve calcification. 相似文献
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Anastasia Ktenioudaki Valérie Chaurin Sofia F. Reis Eimear Gallagher 《International Journal of Food Science & Technology》2012,47(8):1765-1771
Brewer’s spent grain (BSG) was evaluated for its potential as a functional baking ingredient. Scanning electron microscopy (SEM) was used to examine the microstructure of BSG and wheat flours. Baked snacks (breadsticks) were prepared using 15%, 25% and 35% BSG and evaluated for their baking quality and fibre and protein content (over a period of 3 months). The addition of BSG altered the baking characteristics of the breadsticks by affecting their structure and texture. The snacks appeared to lack in cellular structure and crispiness. However, they had quite a stable shelf‐life, as changes in texture, moisture and aw progressed at a low rate. Addition of 25% and 35% BSG significantly increased the protein content of the snacks, and addition of 15% BSG more than doubled the content of dietary fibre in the samples. 相似文献
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Anastasia Stamatiou Peter G. Loutzenhiser Aldo Steinfeld 《American Institute of Chemical Engineers》2012,58(2):625-631
The solar thermochemical production of H2 and CO (syngas) from H2O and CO2 is examined via a two‐step cycle based on Zn/ZnO redox reactions. The first, endothermic step is the thermolysis of the ZnO driven by concentrated solar energy. The second, nonsolar step is the exothermic reaction of Zn with a mixture of H2O and CO2 yielding syngas and ZnO; the latter is recycled to the first step. A series of experimental runs of the second step was carried out in a packed‐bed reactor where ZnO particles provided an effective inert support for preventing sintering and enabling simple and complete recycling to the first, solar step. Experimentation was performed for Zn mass fractions in the range of 33–67 wt % Zn‐ZnO, and inlet gas concentrations in the range 0–75% H2O–CO2, yielding molar Zn‐to‐ZnO conversions up to 91%. A 25 wt % Zn‐ZnO sample mixture produced from the solar thermolysis of ZnO was tested in the same reactor setup and exhibited high reactivity and conversions up to 96%. © 2011 American Institute of Chemical Engineers AIChE J, 2012 相似文献
18.
This article describes the experiences of a Los Angeles inner-city neighbourhood in its attempt for revitalization. The authors headed a Community-University Partnership and worked with graduate students to offer technical support to a neighbourhood-based coalition. The students, local residents, merchants and neighbourhood institutions attempted to follow an asset-based consensus building approach to community development. The article describes the different components of their strategy for physical, economic, cultural and social revitalization, and analyzes the lessons learned from the successes and setbacks of this effort. Finally, the authors discuss some apparent limitations of the asset-based consensus approach. 相似文献
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George C. Papanicolaou Lykourgos C. Kontaxis Anastasia F. Koutsomitopoulou Stephanos P. Zaoutsos 《应用聚合物科学杂志》2015,132(12)
The purpose of the present study is to investigate the quasi‐static and the viscoelastic behavior of epoxy resin reinforced with starch powder. An increase in the elastic modulus on the order of 42% was achieved; a behavior that was predicted by the modulus prediction model (MPM). Next, the composite was subjected to flexural relaxation experiments, in order to determine the relaxation modulus, at different filler‐weight fractions and flexural deflections imposed. The viscoelastic models of the standard linear solid, the power law model and the residual property model (RPM) were applied in order to simulate/predict the stress relaxation curves. Predicted values derived from the application of the above models were compared to each‐other as well as to respective experimental findings. From the above comparison it was proved the superiority of the RPM model in predicting both the linear and the nonlinear viscoelastic response of the materials investigated. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41697. 相似文献
20.
Anastasia Loukaitou-sideris 《Journal of the American Planning Association. American Planning Association》2013,79(2):130-143
This article discusses successful common grounds for children—public settings that enable the harmonious intermingling of children of different backgrounds, races, and ethnicities and that encourage their social interchange, play, educational development, and collaboration. Our study focused on three types of public space that tend to bring these children together: the public school, the park, and the neighborhood community center. The research employed a variety of methods to study the interaction of children 9 to 12 years of age. Field work took place at four sites in West Los Angeles, Santa Monica, and the San Fernando Valley that enjoy a high level of intermixing and have a reputation for promoting diversity. Subjects in the research included children, teachers, and administrators. The article highlights the findings of the field work and concludes with a comparative analysis of the different settings and a discussion of the environmental and programmatic attributes that contribute to their success. 相似文献