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51.
Wesley Pacheco Calixto A. Paulo Coimbra Jesus Carlos da Mota Marcel Wu Wander G. da Silva Bernardo Alvarenga Leonardo da Cunha Brito Aylton Jose Alves Elder Geraldo Domingues Daywes Pinheiro Neto 《International Journal of Numerical Modelling》2015,28(1):78-95
This work presents a genetic operator developed from mathematical methods of curve extrapolation applied in solving problems in geoelectrical prospection. This operator will assist the production of fitter individuals in the population of a genetic algorithm in which inherent patterns of the best individuals of each generation are recognized. The proposed operator in conjunction with a real‐coded genetic algorithm is compared to five alternative optimization techniques known and used in the application to problems in geoelectrical prospection. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
52.
A paradoxical situation exists where vernacular building traditions are in a state of decline and are being replaced by modern counterparts, but they are repeatedly cited in the academic literature as exemplary models of environmental practice. This paradox is examined through research on whether vernacular passive cooling systems in the hot and dry climates of present-day Iran are practicable for the provision of comfortable indoor temperatures. Investigating their technical thermal performance as well as user perceptions and behaviour, positive and negative attributes of the cooling systems are identified. If conclusions about the long-term viability of vernacular buildings are to be drawn, then social, cultural, economic and environmental attributes need to be taken into consideration. Despite rather widespread and persistent assumptions, vernacular building traditions are not necessarily able to survive and the choices made by local people regarding the continuation or abandonment of specific traditions are influenced by a variety of cultural and practical factors. This substantiates the necessity of an integrated and holistic approach that engages with these variables in order to acquire a better understanding of the conditions for the survival of vernacular traditions. Le fait que les traditions architecturales vernaculaires se trouvent dans un état de déclin et sont remplacées par leurs équivalents modernes, alors même qu'elles sont citées à maintes reprises dans la littérature universitaire comme des modèles exemplaires de pratique environnementale, constitue une situation paradoxale. Ce paradoxe est étudié au travers de recherches visant à déterminer si les systèmes de refroidissement passif vernaculaires sous les climats chauds et secs de l'Iran d'aujourd'hui peuvent être mis en pratique pour assurer des températures intérieures confortables. L’étude de leurs performances thermiques techniques aussi bien que des perceptions et du comportement des utilisateurs permet d'identifier les attributs positifs et négatifs des systèmes de refroidissement. S'il faut tirer des conclusions concernant la viabilité à long terme des bâtiments vernaculaires, il est alors nécessaire de prendre en considération les attributs sociaux, culturels, économiques et environnementaux. En dépit de présomptions plutôt répandues et tenaces, les traditions architecturales vernaculaires ne sont pas nécessairement capables de survivre et les choix opérés par les populations locales quant à la poursuite ou l'abandon de traditions spécifiques sont influencés par divers facteurs culturels et pratiques. Ceci confirme la nécessité d'une approche intégrée et holistique qui, par ces variables, incite à acquérir une meilleure compréhension des conditions propres à assurer la survie des traditions vernaculaires. Mots clés: confort adaptatif, performances des bâtiments, attentes, traditions locales, occupants, refroidissement passif, architecture vernaculaire, Iran 相似文献
53.
11C‐ and 18F‐Labeled Radioligands for P‐Glycoprotein Imaging by Positron Emission Tomography
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Dr. Mariangela Cantore Marcel Benadiba Philip H. Elsinga Chantal Kwizera Rudi A. J. O. Dierckx Nicola Antonio Colabufo Gert Luurtsema 《ChemMedChem》2016,11(1):108-118
P‐Glycoprotein (P‐gp) is an efflux transporter widely expressed at the human blood–brain barrier. It is involved in xenobiotics efflux and in onset and progression of neurodegenerative disorders. For these reasons, there is great interest in the assessment of P‐gp expression and function by noninvasive techniques such as positron emission tomography (PET). Three radiolabeled aryloxazole derivatives: 2‐[2‐(2‐methyl‐(11C)‐5‐methoxyphenyl)oxazol‐4‐ylmethyl]‐6,7‐dimethoxy‐1,2,3,4‐tetrahydroisoquinoline ([11C]‐ 5 ); 2‐[2‐(2‐fluoromethyl‐(18F)‐5‐methoxyphenyl)oxazol‐4‐ylmethyl]‐6,7‐dimethoxy‐1,2,3,4‐tetra‐hydroisoquinoline ([18F]‐ 6 ); and 2‐[2‐(2‐fluoroethyl‐(18F)‐5‐methoxyphenyl)oxazol‐4‐ylmethyl]‐6,7‐dimethoxy‐1,2,3,4‐tetrahydroisoquinoline ([18F]‐ 7 ), were tested in several in vitro biological assays to assess the effect of the aryl substituent in terms of potency and mechanism of action toward P‐gp. Methyl derivative [11C]‐ 5 is a potent P‐gp substrate, whereas the corresponding fluoroethyl derivative [18F]‐ 7 is a P‐gp inhibitor. Fluoromethyl compound [18F]‐ 6 is classified as a non‐transported P‐gp substrate, because its efflux increases after cyclosporine A modulation. These studies revealed a promising substrate and inhibitor, [11C]‐ 5 and [18F]‐ 7 , respectively, for in vivo imaging of P‐gp by using PET. 相似文献
54.
Structure–Activity Relationships of JMV4463, a Vectorized Cathepsin D Inhibitor with Antiproliferative Properties: The Unique Role of the AMPA‐Based Vector
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Dr. Lubomir L. Vezenkov Clément A. Sanchez Dr. Virginie Bellet Dr. Vincent Martin Dr. Marie Maynadier Dr. Nadir Bettache Prof. Vincent Lisowski Prof. Jean Martinez Dr. Marcel Garcia Dr. Muriel Amblard Dr. Jean‐François Hernandez 《ChemMedChem》2016,11(3):302-308
Cathepsin D (CathD) is overexpressed and secreted by several solid tumors and stimulates their growth, the mechanism of which is still not understood. In this context, the pepstatin bioconjugate JMV4463 [Ac‐arg‐O2Oc‐(Val)3‐Sta‐Ala‐Sta‐(AMPA)4‐NH2; O2Oc=8‐amino‐3,6‐dioxaoctanoyl, Sta=statine, AMPA=ortho‐aminomethylphenylacetyl], containing a new kind of cell‐penetrating vector, was previously shown to exhibit potent antiproliferative effects in vitro and to delay the onset of tumors in vivo. In this study, we performed a structure–activity relationship analysis to evaluate the significance of the inhibitor and vector moieties of JMV4463. By modifying both statine residues of pepstatin we found that the antiproliferative activity is correlated with CathD inhibition, supporting a major role of the catalytic activity of intracellular CathD in cancer cell proliferation. Replacing the vector composed of four AMPA units with other vectors was found to abolish cytotoxicity, although all of the conjugates enabled pepstatin transport into cells. In addition, the AMPA4 vector must be localized at the C terminus of the bioconjugate. The unexpected importance of the vector structure and position for cytotoxic action suggests that AMPA4 enables pepstatin to inhibit the proteolysis of critical CathD substrates involved in cell proliferation via a unique mechanism of action. 相似文献
55.
Marcel Richter Yuriy Zakrevskyy Michael Eisele Nino Lomadze Svetlana Santer Regine v. Klitzing 《Polymer》2014
The contraction/swelling transition of anionic PNIPAM-co-AAA particles can be manipulated by light using interactions with cationic azobenzene-containing surfactant. In this study the influence of pH-buffers and their concentrations, the charge density (AAA content) in microgel particles as well as the spacer length of the surfactant on the complex formation between the microgel and surfactant is investigated. It is shown that the presence of pH buffer can lead to complete blocking of the interactions in such complexes and the resulting microgel contraction/swelling response. There is a clear competition between the buffer ions and the surfactant molecules interacting with microgel particles. When working in pure water solutions with fixed concentration (charge density) of microgel, the contraction/swelling of the particles is controlled only by relative concentration (charge ratio) of the surfactant and AAA groups of the microgel. Furthermore, the particle contraction is more efficient for shorter spacer length of the surfactant. The onset point of the contraction process is not affected by the surfactant hydrophobicity. This work provides new insight into the interaction between microgel particles and photo-sensitive surfactants, which offers high potential in new sensor systems. 相似文献
56.
Feng Zhu Berhane T. Weldegergis Boris Lhie Jeffrey A. Harvey Marcel Dicke Erik H. Poelman 《Journal of chemical ecology》2014,40(9):986-995
Foraging success of parasitoids depends on the utilization of reliable information on the presence of their often, inconspicuous hosts. These parasitic wasps use herbivore-induced plant volatiles (HIPVs) that provide reliable cues on host presence. However, host searching of hyperparasitoids, a group of parasitoids that parasitize the larvae and pupae of other parasitoids, is more constrained. Their hosts do not feed on plants, and often are even concealed inside the body of the herbivore host. Hyperparasitoids recently have been found to use HIPVs of plants damaged by herbivore hosts in which the parasitoid larvae develop. However, hyperparasitoids that search for these parasitoid larvae may be confronted with healthy and parasitized caterpillars on the same plant, further complicating their host location. In this study, we addressed whether the primary hyperparasitoid Baryscapus galactopus uses caterpillar body odors to discriminate between unparasitized herbivores and herbivores carrying larvae of parasitoid hosts. We show that the hyperparasitoids made faster first contact and spent a longer mounting time with parasitized caterpillars. Moreover, although the three parasitoid hosts conferred different fitness values for the development of B. galactopus, the hyperparasitoids showed similar behavioral responses to caterpillar hosts carrying different primary parasitoid hosts. In addition, a two-chamber olfactometer assay revealed that volatiles emitted by parasitized caterpillars were more attractive to the hyperparasitoids than those emitted by unparasitized caterpillars. Analysis of volatiles revealed that body odors of parasitized caterpillars differ from unparasitized caterpillars, allowing the hyperparasitoids to detect their parasitoid host. 相似文献
57.
Gerhard Heise Andreas Brner Marcel Dickmann Marina Englmaier Andreas Heiss Matthias Kemnitzer Jan Konrad Regina Moser Jrg Palm Helmut Vogt Heinz P. Huber 《Progress in Photovoltaics: Research and Applications》2015,23(10):1291-1304
In this paper, we present the selective structuring of all three patterns (P1, P2 and P3) of a monolithic interconnection of CIS (Cu(In,Ga)(S,Se)2) thin film solar cells by picosecond laser pulses at a wavelength of 1064 nm. We show results for single pulse ablation threshold values and line scribing of molybdenum films on glass (P1), CIS on molybdenum (P2) and zinc oxide on CIS (P3). The purposes of these processes are the p‐type isolation (P1), cell interconnect (P2) and n‐type isolation (P3), which are required for complete cell architecture. The half micron thick molybdenum back electrode can be structured with a process speed of more than 15 m/s at about 15 W average power without detectable residues and damage by direct induced laser ablation from the back side (P1). The CIS layer can be structured selectively down to the molybdenum at process speeds up to 1 m/s at about 15 W average power, due to the precision of direct laser ablation in the ultrashort pulse regime (P2). The ZnO front electrode layer is separated by clean trenches with straight side walls at process speeds of up to 15 m/s at about 10 W average power, as a result of indirect induced laser ablation (P3). A validation of functionality of all processes is demonstrated on CIS solar cell modules (30 × 30 cm2). By replacing one state‐of‐the‐art process by a picosecond laser process at a time, solar efficiencies could be increased for P1 and P2 and stayed on a similar level for P3. After an optimization of the patterning processes in the R&D pilot line of AVANCIS, we achieved a new record efficiency for an all‐laser‐patterned CIS solar module: 14.7% as best value for the aperture area efficiency of a 30 × 30 cm2 sized CIS module was reached. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
58.
Jeremy A. Nestele Anne-Katrin Rohlfing Valerie Dicenta Alexander Bild Daniela Eißler Frederic Emschermann Marcel Kremser Konstantin Krutzke Tilman E. Schffer Oliver Borst Moran Levi Netanel Korin Meinrad Paul Gawaz 《International journal of molecular sciences》2022,23(1)
Traditional antithrombotic agents commonly share a therapy-limiting side effect, as they increase the overall systemic bleeding risk. A novel approach for targeted antithrombotic therapy is nanoparticles. In other therapeutic fields, nanoparticles have enabled site-specific delivery with low levels of toxicity and side effects. Here, we paired nanotechnology with an established dimeric glycoprotein VI-Fc (GPVI-Fc) and a GPVI-CD39 fusion protein, thereby combining site-specific delivery and new antithrombotic drugs. Poly(lactic-co-glycolic acid) (PLGA) nanoparticles, NP-BSA, NP-GPVI and NP-GPVI-CD39 were characterized through electron microscopy, atomic force measurements and flow cytometry. Light transmission aggregometry enabled analysis of platelet aggregation. Thrombus formation was observed through flow chamber experiments. NP-GPVI and NP-GPVI-CD39 displayed a characteristic surface coating pattern. Fluorescence properties were identical amongst all samples. NP-GPVI and NP-GPVI-CD39 significantly impaired platelet aggregation. Thrombus formation was significantly impaired by NP-GPVI and was particularly impaired by NP-GPVI-CD39. The receptor-coated nanoparticles NP-GPVI and the bifunctional molecule NP-GPVI-CD39 demonstrated significant inhibition of in vitro thrombus formation. Consequently, the nanoparticle-mediated antithrombotic effect of GPVI-Fc, as well as GPVI-CD39, and an additive impact of CD39 was confirmed. In conclusion, NP-GPVI and NP-GPVI-CD39 may serve as a promising foundation for a novel therapeutic approach regarding targeted antithrombotic therapy. 相似文献
59.
Optimization of alcohol‐free beer production by lager and cachaça yeast strains using response surface methodology
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Cláudia Puerari Jan Strejc Angélica C. Souza Marcel Karabín Rosane F. Schwan Tomáš Brányik 《Journal of the Institute of Brewing》2016,122(1):69-75
Alcohol‐free beers (AFBs) are an attractive segment of the beer market both for the brewing industry and for consumers. While AFBs produced by arrested/limited fermentation often suffer from a lack of volatile compounds, beer flavour can be improved by yeast selection and optimization of fermentation conditions. The yeast selection strategy was demonstrated by comparing traditional lager yeast with selected cachaça yeast strains. Correspondingly, response surface methodology was used to enhance the formation of the flavour‐active volatile compounds by optimization of the fermentation conditions (original wort extract, fermentation temperature, pitching rate). Statistical analysis of the experimental data revealed the relative significance of process variables and their interactions. The developed quadratic model describing the responses of total esters and higher alcohols to changes in process variables was used to predict the ideal fermentation conditions in terms of flavour formation. The predicted conditions were experimentally verified and alternative strategies of AFB production are suggested. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
60.
Due to the recognized toxicity of acrylamide, intensive efforts have been made to reduce the concentration of this undesired Maillard by-product in food. This work reports the results obtained from a series of experiments aimed at determining the concentration of acrylamide and the in vitro radical scavenging capacity in the same roasted and ground coffee samples, as it is well established that a significant part of the antioxidant activity in coffee is linked to the melanoidins, which are also considered as Maillard reaction products (MRPs). The radical scavenging capacity was measured using electroparamagnetic resonance (EPR). Coffee samples from the Robusta and Arabica varieties were roasted at 236 °C over different time periods to obtain very light, light, medium and dark roast. Color analyses were performed on all samples. Increasing the roasting degree led to a decrease in acrylamide concentration as well as radical scavenging capacity. The results of this work indicate that any mitigation efforts must also take into account the potential loss of desired food constituents and consequently changes to the risk/benefit characteristics of foods. 相似文献