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71.
Esther Hontañón Marcel Rouenhoff Alfredo Azabal Emilio Ramiro Frank Einar Kruis 《Aerosol science and technology》2014,48(3):333-339
An existing differential mobility analyzer (DMA) of cylindrical electrodes and a novel DMA of rectangular plate electrodes are demonstrated for size fractionation of nanoparticles at high-aerosol flow rates in this work. The two DMAs are capable of delivering monodisperse size selected nanoparticles (SMPS σg < 1.1) at gas flow rates ranging from 200 slm to 500 slm. At an aerosol flow rate of 200 slm, the maximum attainable particle mean size is of about 20 nm for the cylindrical DMA and of nearly 50 nm for the rectangular plate DMA. The number concentration of the monodisperse nanoparticles delivered by the high-flow DMAs spans from 104 cm?3 to 106 cm?3 depending upon the particle mean size and particle size dispersion.
Copyright 2014 American Association for Aerosol Research 相似文献
72.
For measurement outside the laboratory, uncertainty evaluations have to be model-based. Therefore models should not only represent the measurand but also its environment. For measurement in social science these models will be too complex, therefore instead of white-box models, grey-box (modular-designed) models are preferred. They are much simpler. Uncertainty evaluations of measurements outside the laboratory are more of the kind of Type B evaluations. In social science, due to the lack of authoritative scientific institutions, Type B evaluations will be of a different character. In case of measurements based on grey-box models they are the so-called structure-oriented behaviour tests. 相似文献
73.
The presence of saliva in the oral environment is relevant for several essential health processes. However, the noncontrolled early saliva interaction with biomaterials manufactured for oral rehabilitation may generate alterations in the superficial properties causing negative biological outcomes. Therefore, the present review aimed to provide a compilation of all possible physical–chemical–biological changes caused by the early saliva interaction in dental implants and materials for oral regeneration. Dental implants, bone substitutes and membranes in dentistry possess different properties focused on improving the healing process when in contact with oral tissues. The early saliva interaction was shown to impair some positive features present in biomaterials related to quick cellular adhesion and proliferation, such as surface hydrophilicity, cellular viability and antibacterial properties. Moreover, biomaterials that interacted with contaminated saliva containing specific bacteria demonstrated favorable conditions for increased bacterial metabolism. Additionally, the quantity of investigations associating biomaterials with early saliva interaction is still scarce in the current literature and requires clarification to prevent clinical failures. Therefore, clinically, controlling saliva exposure to sites involving the application of biomaterials must be prioritized in order to reduce impairment in important biomaterial properties developed for rapid healing. 相似文献
74.
Daniela Grimm Herbert Schulz Marcus Krüger Jos Luis Corts-Snchez Marcel Egli Armin Kraus Jayashree Sahana Thomas J. Corydon Ruth Hemmersbach Petra M. Wise Manfred Infanger Markus Wehland 《International journal of molecular sciences》2022,23(6)
Cancer is a disease exhibiting uncontrollable cell growth and spreading to other parts of the organism. It is a heavy, worldwide burden for mankind with high morbidity and mortality. Therefore, groundbreaking research and innovations are necessary. Research in space under microgravity (µg) conditions is a novel approach with the potential to fight cancer and develop future cancer therapies. Space travel is accompanied by adverse effects on our health, and there is a need to counteract these health problems. On the cellular level, studies have shown that real (r-) and simulated (s-) µg impact survival, apoptosis, proliferation, migration, and adhesion as well as the cytoskeleton, the extracellular matrix, focal adhesion, and growth factors in cancer cells. Moreover, the µg-environment induces in vitro 3D tumor models (multicellular spheroids and organoids) with a high potential for preclinical drug targeting, cancer drug development, and studying the processes of cancer progression and metastasis on a molecular level. This review focuses on the effects of r- and s-µg on different types of cells deriving from thyroid, breast, lung, skin, and prostate cancer, as well as tumors of the gastrointestinal tract. In addition, we summarize the current knowledge of the impact of µg on cancerous stem cells. The information demonstrates that µg has become an important new technology for increasing current knowledge of cancer biology. 相似文献
75.
Wael E. Houssen Dr. Stephen H. Wright Dr. Arnout P. Kalverda Dr. Gary S. Thompson Dr. Sharon M. Kelly Dr. Marcel Jaspars Prof. 《Chembiochem : a European journal of chemical biology》2010,11(13):1867-1873
The solution structure of the leader sequence of the patellamide precursor peptide was analysed by using CD and determined with NOE‐restrained molecular dynamics calculations. This leader sequence is highly conserved in the precursor peptides of some other cyanobactins harbouring heterocycles, and is assumed to play a role in targeting the precursor peptide to the post‐translational machinery. The sequence was observed to form an α‐helix spanning residues 13–28 with a hydrophobic surface on one side of the helix. This hydrophobic surface is proposed to be the site of the initial binding with modifying enzymes. 相似文献
76.
Social impacts and degrees of organization inherent to opinion formation for interacting agents on networks present interesting
questions of general interest from physics to sociology. We present a quantitative analysis of a case implying an evolving
small size network, i.e. that inherent to the ongoing debate between modern creationists (most are Intelligent Design (ID)
proponents (IDP) and Darwin’s theory of Evolution Defenders (DED)). This study is carried out by analyzing the structural
properties of the citation network unfolded in the recent decades by publishing works belonging to members of the two communities.
With the aim of capturing the dynamical aspects of the interaction between the IDP and DED groups, we focus on two key quantities,
namely, the degree of activity of each group and the corresponding degree of impact on the intellectual community at large.
A representative measure of the former is provided by the rate of production of publications (RPP), whilst the latter can
be assimilated to the rate of increase in citations (RIC). These quantities are determined, respectively, by the slope of
the time series obtained for the number of publications accumulated per year and by the slope of a similar time series obtained
for the corresponding citations. The results indicate that in this case, the dynamics can be seen as geared by triggered or
damped competition. The network is a specific example of marked heterogeneity in exchange of information activity in and between
the communities, particularly demonstrated through the nodes having a high connectivity degree, i.e. opinion leaders. 相似文献
77.
Comparison of vacuum impregnation and soaking techniques for addition of the probiotic Lactobacillus acidophilus to minimally processed melon
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Patrícia Martins de Oliveira Afonso Mota Ramos Eliane Maurício Furtado Martins Érica Nascif Rufino Vieira Ariana de Souza Soares Marcel Cardoso de Noronha 《International Journal of Food Science & Technology》2017,52(12):2547-2554
This study aimed to evaluate the vacuum impregnation (VI) and soaking methods in the addition of Lactobacillus acidophilusLA‐3 to minimally processed melon (MPM). The melons were washed, sanitised in chlorine solution (200 mg L?1), peeled and cutted into cubes. Lactobacillus acidophilusLA‐3 (1.4 × 1010 CFU g?1) were added to the MPM through both techniques. The L. acidophilusLA‐3 count in MPM was similar to those commonly found in dairy products having probiotic claim, but VI was more efficient than soaking in maintaining the viability (8.61 and 7.98 Log CFU g?1, respectively). The pH, acidity and soluble solids were not affected by probiotic culture and the incorporation technique; however, the VI affected the firmness of fruit. The MPM was within Brazilian standards for their microbiological characteristics. MPM may be used as a carrier of probiotic bacteria, being one more alternative for individuals who consume probiotic products. 相似文献
78.
Servervirtualisierung 总被引:4,自引:4,他引:0
79.
Jean Marcel Pallo 《Information Processing Letters》2009,109(10):514-50
A restricted rotation induced by a weak associative law is introduced. The corresponding equivalence relation is identical to the Glivenko congruence on Tamari lattices, i.e. lattices of binary trees endowed by the well-known rotation operation. 相似文献
80.
Univ.-Prof. DI Dr. Helmut Habersack DI Marlene Haimann Ass. Prof. Dr. Sándor Baranya Prof. Dr. János Józsa Mag. Angelika Riegler Dr Christine Sindelar DI Marcel Liedermann Johanna Ficsor Gabriella Mohácsiné Simon HR DI Dr. Michael Hengl 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):340-347
The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m3/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed. 相似文献