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Assessing internal Software Quality Attributes of the Object-Oriented and Service-Oriented Software Development Paradigms: A Comparative Study

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Journal of Software Engineering and Applications 2011年第4期4卷 244-252页

作者： Yaser i. Mansour Suleiman H. Mustafa 不详

Service-Oriented Architecture (SOA) is becoming the dominant approach for developing and organizing distributed enterprise-wide applications. Although the concepts of SOA have been extensively described in the literature and in-dustry, the effects of adopting SOA on software quality are still unclear. The aim of the paper is to analyze how adopt-ing SOA can affect software quality as opposed to the Object-Oriented (OO) paradigm and expose the differential implications of adopting both paradigms on software quality. The paper provides a brief introduction of the architectural differences between the Service-Oriented (SO) and OO paradigms and a description of internal software quality metrics used for the comparison. The effects and differences are exposed by providing a case study architected for both paradigms. The quantitative measure concluded in the paper showed that a software system developed using SOA approach provides higher reusability and lower coupling among software modules, but at the same time higher complexity than those of the OO approach. it was also found that some of the existing OO software quality metrics are inapplicable to SOA software systems. As a consequence, new metrics need to be developed specifically to SOA software systems.

关键词： Service-Oriented Architecture Object-Orientation internal Software Quality Attributes Software Quality Metrics

Simultaneous Preservation of Soil Structural Properties and Phospholipid Profiles: A Comparison of Three Drying Techniques

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Pedosphere 2008年第3期18卷 284-287页

作者： L. J. DEACON D. V. GRiNEV J. W. CRAWFORD J. HARRiS K. RiTZ i. M. YOUNG National Soil Resources institute Department of Natural Resources School of Applied Sciences Cranfield University Cranfield MK43 0AL (UK) SiMBiOS Centre University of Abertay Dundee DD1 1HG (UK) integrated Earth Systems Science institute Department of Natural Resources School of Applied Sciences Cranfield University Cranfield MK43 0AL (UK)

There is a need to simultaneously preserve evidence of interactions between the biological community and soil struc- tural properties of a soil in as near an intact(natural)state as *** dehydration techniques were implemented and assessed for their ability to minimise disruption of both biological and physical properties of the same arable soil *** techniques applied until samples were at constant weight were i)air-drying at 20°C(AD);ii) -80°C freeze for 24 h,followed by freeze-drying(-80FD);and iii)liquid nitrogen snap freeze,followed by freeze-drying (LNFD)and were compared to a moist *** structure was determined and quantified in three dimensions using X-ray computed tomography and microbial phenotypic community composition was assessed using phospholipid fatty acid(PLFA)*** study confirms that any form of dehydration,when preparing soil for simultaneous biological and physical analysis,will alter the soil physical properties,and cause some change in apparent community ***-drying(both the LNFD and-80FD treatments)was found to minimise disruption(when compared to the moist control soil)to both the soil physical properties and the community structure and is a preferable technique to air-drying which markedly alters the size and character of the pore network,as well as the phenotypic *** LNFD was the preferred treatment over the-80FD treatment as samples show low variability between replicates and a fast turn-around time between *** snap freezing in liquid nitrogen,followed by freeze drying is the most appropriate form of dehydration when two sets of data,both physical and biological,need to be preserved simultaneously from a soil core.

关键词：生物群落脱水作用磷脂干燥环境

Apoptosis induced by N-Nitrosamines in Two Cancer Cell Lines

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Journal of Environmental Protection 2010年第3期1卷 314-323页

作者： Paloma Morales Nuria Arranz Ana i. Haza 不详

in the present study, we investigated the induction of apoptosis by N-nitrosopyrrolidine (NPYR) and N-nitrosodimethy-lamine (NDMA) in two human cell lines: HL-60 (leukemia) and HepG2 (hepatoma). Apoptotic cells were identified by: 1) chromatin condensation, 2) flow cytometry analysis and 3) poly (ADP-ribose) polymerase cleavage. Both cell lines exhibited morphological changes consistent with apoptotic events following treatment with N-nitrosamines. Flow cytometry analysis showed that both N-nitrosamines induced apoptotic cell death in a concentration and time dependent- manner. NPYR was stronger than NDMA, since it induced a significant apoptotic cell death after 72 h starting from a concentration of 10 mM, whereas NDMA was effective at 27 mM. Furthermore, NPYR and NDMA caused the cleavage of PARP in HL-60 cells whereas no PARP cleavage was detected in HepG2 cells. However, NPYR- and NDMA-induced cell death in HepG2 cells was prevented by specific caspase inhibitors. Caspase-8 mediated main pathway and was responsible for 76% (NPYR) and 64% (NDMA) inhibition of apoptosis. The data demonstrate that NPYR and NDMA induce apoptosis in HL-60 and HepG2 cell lines via caspase-dependent pathway.

关键词： N-nitrosopyrrolidine N-nitrosodimethylamine Apoptosis Caspases HL-60 Cells HepG2 Cells

Evaluation of Left Ventricular Function after Percutaneous Recanalization of Chronic Coronary Occlusions: The Role of Two-Dimensional Speckle Tracking Echocardiography

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World Journal of Cardiovascular Diseases 2019年第12期9卷 899-914页

作者： Ahmed Emara shady Zahran Neveen i. Samy Faculty of Medicine Menoufia University Menoufia Egypt Elagouza Charity Hospital Giza Egypt

Background: The recanalization of a chronic total coronary occlusion is the possible way to improve left ventricular (LV) function through the recovery of hibernating myocardium. Aim: The aim of this study is to evaluate the role of 2D speckle tracking in evaluation of the left ventricular (LV) systolic function in chronic total occlusion (CTO) patients before and at 1 day as well as 3 months after percutaneous coronary intervention (PCi). Patients and Methods: A prospective observational study included 40 patients diagnosed with coronary angiography to have a chronic total occlusion. Percutaneous coronary revascularization was performed according to standard practices with the femoral approach. Conventional 2D echocardiography was used to assess LV functions and wall motion abnormalities scoring index (WMAi). Using speckle-tracking echocardiography was to measure global longitudinal strain (GLS) and. Follow-up of patients was done at day 1 and 3 months later after PCi. Results: Forty patients were included in this study, with a mean age of 58.55 ± 7.98 years. GLS and WMAi difference at baseline and follow-up shows a positive correlation with left ventricular ejection fraction (LVEF) changes at baseline and follow-up (p Conclusion: The results of this study provide evidence to support the clinical use of 2D-STE to monitor the early changes of LV function. in patients undergoing CTO revascularization, change in GLS was more sensitive predictors for LV function improvement at 3-month follow-up.

关键词： Chronic Total Occlusions Left Ventricular Function Percutaneous Coronary intervention Ejection Fraction Speckle Tracking Echocardiography

independence of the Residual Quadratic Sums in the Dispersion Equation with Noncentral χ<sup>2</sup>-Distribution

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Applied Mathematics 2011年第10期2卷 1303-1308页

作者： Nikolay i. Sidnyaev Kristina S. Andreytseva 不详

A model adequacy test should be carried out on the basis of accurate aprioristic ideas about a class of adequate models, as in solving of practical problems this class is final. in article, the quadratic sums entering into the equation of the dispersive analysis are considered and their independence is proved. Necessary and sufficient conditions of existence of adequate models are resulted. it is shown that the class of adequate models is infinite.

关键词： Noncentral χ2--Distribution Dispersion Analysis Adequate Models Quadratic Sums

Na induced Changes in the Electronic Band Structure of Graphene Grown on C-Face SiC

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Graphene 2013年第1期2卷 1-7页

作者： Leif i.Johansson Chao Xia Chariya Virojanadara Department of Physics Chemistry and BiologyLinkoping UniversityLinkopingSweden

Studies of the effects induced on the electron band structure after Na deposition, and subsequent heating, on a C-face 2 MLs graphene sample are reported. Na deposition shifts the Dirac point downwards from the Fermi level by about 0.5 eV due to electron doping. After heating at temperatures from around 120℃ to 300℃,thep-band appears considerably broadened. Collected Si 2p and Na 2p spectra then indicate Na intercalation in between the graphene layers and at the graphene SiC interface. The broadening is therefore interpreted to arise from the presence of two slightly shifted, but not clearly resolved,p-bands. Constant energy photoelectron distribution patterns, E(kx,ky);s, extracted from the clean 2MLs graphene C-face sample look very similar to earlier calculated distribution patterns for monolayer, but not Bernal stacked bilayer, graphene. After Na deposition the patterns extracted at energies below the Dirac point appear very similar so the doping had no pronounced effect on the shape or intensity distribution. At energies above the Dirac point the extracted angular distribution patterns show the flipped, “mirrored”, intensity distribution predicted for monolayer graphene at these energies. An additional weaker outer band is also discernable at energies above the Dirac point, which presumably is induced by the deposited Na.

关键词： Graphene on C-Face SiC Graphene Band Structure Na intercalation Constant Energy Photoelectron Angular Distribution Patterns

Dynamical Properties of the Superposition of Two Finite Trio Coherent States

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Journal of Quantum information Science 2019年第1期9卷 98-109页

作者： Salama i. Ali Ahmed M. Mosallem Mathematics Department Faculty of Science Hail University Hail City Saudi Arabia Mathematics Department Faculty of Science Al-Azher University Cairo Egypt Department of Mathematics and Theoretical Physics Nuclear Research Centre Atomic Energy Authority Cairo Egypt

in this contribution we study a superposition of two finite dimensional trio coherent states (FTCS). The state is regarded as a correlated three-mode state in finite dimensional bases. The framework of Pegg and Barnett formalism, and the phase distribution in addition to the Poissonian distribution are examined. it is shown that the eigenvalue of the difference of the photon number (the q-parameter) is responsible for the non-classical phenomenon. Furthermore, the quasi-probability distribution functions (the Wigner and Q-functions) are also discussed. in this case and for the Wigner function the non-classical behavior is only reported for the odd values of the q-parameter.

关键词： Entropy Squeezing Atomic Wehrl Entropy Marginal Atomic Q-Function

Simplified Life Cycle Analysis: A Rural School in La Pampa, Argentina

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American Journal of Climate Change 2014年第1期3卷 22-32页

作者： Mariela i. Marcilese Jorge D. Czajkowski Laboratorio de Arquitectura y Hábitat Sustentable (LAyHS) Facultad de Arquitectura y Urbanismo (FAU) La Plata Argentina Universidad Nacional de La Plata (UNLP) La Plata Argentina

This study case is a rural school in La Pampa, Argentina, where we compare two energy efficiency systems for construction: the local traditional building type and a proposed one, based on passive system design during its life cycle. in addition, we assume that savings of emissions of greenhouse-gases are valued in terms of Argentina’s energy matrix. The efficiency, in terms of energy, involves the consumption for its manufacture (extraction, transport and assembly of materials), construction, maintenance and dismantling, recycling and final disposal of waste. Knowing this information at the preliminary stage can be advantageous to evaluate the selected materials in terms of energy and cost savings to amortize its value over the life cycle, and introduce other types of design. At present, there are significant problems of resource scarcity. The implementation of the analysis of life cycle (LC) should be a significant contribution in the field of construction in reference to awareness about energy conservation and efficiency, and therefore contributing to the sustainable development of societies.

关键词： Energy Efficiency Rural School Life Cycle

Multiple stacking of inGaAs/GaAs(731) nanostructures

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Nano-Micro Letters 2009年第1期1卷 1-3页

作者： Y.Z.Xie V.P.Kunets Z.M.Wang V.Dorogan Y.i.Mazur J.Wu G.J.Salamo institute of Nanoscale Science and Engineering University of Arkansas

We studied the multilayering effects of inGaAs quantum dots(QDs) on GaAs(731), a surface lying inside of the stereographic triangle. The surfaces after stacking 16 inGaAs layers were characterized with highly non-uniformity of QD spatial distribution. The bunched step regions driven by strain accumulation are decorated by QDs, therefore GaAs(731) becomes a good candidate substrate for the growth of QD clusters. The unique optical properties of the QD clusters are revealed by photoluminescence measurements. By adjusting the coverage of inGaAs, a bamboo-like nanostructured surface was observed and the quantum dots aligned up in clusters to separate the "bamboo" into sections.

关键词： Quantum dots MBE High index surfaces Nanostructures Atomic force microscopy