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921.
Receptor‐Mediated Uptake of Boron‐Rich Neuropeptide Y Analogues for Boron Neutron Capture Therapy 下载免费PDF全文
Dr. Verena M. Ahrens Dr. René Frank Solveig Boehnke Dr. Christian L. Schütz Dr. Gabriele Hampel Dorothée S. Iffland Prof. Dr. Nicolas H. Bings Prof. Dr. Evamarie Hey‐Hawkins Prof. Dr. Annette G. Beck‐Sickinger 《ChemMedChem》2015,10(1):164-172
Peptidic ligands selectively targeting distinct G protein‐coupled receptors that are highly expressed in tumor tissue represent a promising approach in drug delivery. Receptor‐preferring analogues of neuropeptide Y (NPY) bind and activate the human Y1 receptor subtype (hY1 receptor), which is found in 90 % of breast cancer tissue and in all breast‐cancer‐derived metastases. Herein, novel highly boron‐loaded Y1‐receptor‐preferring peptide analogues are described as smart shuttle systems for carbaboranes as 10B‐containing moieties. Various positions in the peptide were screened for their susceptibility to carbaborane modification, and the most promising positions were chosen to create a multi‐carbaborane peptide containing 30 boron atoms per peptide with excellent activation and internalization patterns at the hY1 receptor. Boron uptake studies by inductively coupled plasma mass spectrometry revealed successful uptake of the multi‐carbaborane peptide into hY1‐receptor‐expressing cells, exceeding the required amount of 109 boron atoms per cell. This result demonstrates that the NPY/hY receptor system can act as an effective transport system for boron‐containing moieties. 相似文献
922.
Septic tanks are widely used in on‐site wastewater treatment systems. In addition to anaerobic pretreatment, hydraulic buffering is one of the roles attributed to septic tanks. However, there is still no tool for assessing it, especially in dynamic conditions. For gravity fed‐system, it could help both researchers and system designers. This technical note reports a simple mechanistic model based on the assumption of flow transition between the septic tank and the outflow pipe. The only parameter of this model was calibrated using computational fluid dynamics (CFD) modeling for a wide range of discharge rates. The resulting model highlights that a septic tank plays a hydraulic buffer role when faced with sudden and large discharge flow, but this role tends to disappear when input hydrographs are smoother. In those cases, there is an observable lag between the input hydrograph and outflow hydrograph. 相似文献
923.
Roey Elnathan Bahman Delalat Daniel Brodoceanu Hashim Alhmoud Frances J. Harding Katrin Buehler Adrienne Nelson Lucio Isa Tobias Kraus Nicolas H. Voelcker 《Advanced functional materials》2015,25(46):7215-7225
Vertically aligned silicon nanowire (VA‐SiNW) arrays are emerging as a powerful new tool for gene delivery by means of mechanical transfection. In order to utilize this tool efficiently, uncertainties around the required design parameters need to be removed. Here, a combination of nanosphere lithography and templated metal‐assisted wet chemical etching is used to fabricate VA‐SiNW arrays with a range of diameters, heights, and densities. This fabrication strategy allows identification of critical parameters of surface topography and consequently the design of SiNW arrays that deliver plasmid with high transfection efficiency into a diverse range of human cells whilst maintaining high cell viability. These results illuminate the cell‐materials interactions that mediate VA‐SiNW transfection and have the potential to transform gene therapy and underpin future treatment modalities. 相似文献
924.
Characterization of Lactobacillus isolates from fermented olives and their bacteriocin gene profiles
Hurtado A Ben Othman N Chammem N Hamdi M Ferrer S Reguant C Bordons A Rozès N 《Food microbiology》2011,28(8):1514-1518
Near one hundred isolates of Lactobacillus paraplantarum, Lactobacillus pentosus and Lactobacillus plantarum from table olives were studied. Strains were genotyped by rep-PCR. Although the technique failed to differentiate some isolates at the species level, it proved a robust and easy procedure that could be useful for distinguishing between related strains of L. paraplantarum, L. pentosus and L. plantarum from a large pool of unrelated strains of these species. A PCR-based screening revealed the presence of the plantaricin encoding genes plnA, plnB, plnC, plnD, plnE/F, plnF, plnI, plnJ, plnK, plnG and plnN in most isolates of the three species. Sequences of bacteriocin genes present in L. paraplantarum and L. pentosus were homologous to L. plantarum genes. Through a discriminating analysis of the bacteriocin gene profiles, it was possible to establish a relationship between the origin of isolation and the LAB isolates, regardless of species. 相似文献
925.
Wafer bonded four‐junction GaInP/GaAs//GaInAsP/GaInAs concentrator solar cells with 44.7% efficiency
Frank Dimroth Matthias Grave Paul Beutel Ulrich Fiedeler Christian Karcher Thomas N. D. Tibbits Eduard Oliva Gerald Siefer Michael Schachtner Alexander Wekkeli Andreas W. Bett Rainer Krause Matteo Piccin Nicolas Blanc Charlotte Drazek Eric Guiot Bruno Ghyselen Thierry Salvetat Aurlie Tauzin Thomas Signamarcheix Anja Dobrich Thomas Hannappel Klaus Schwarzburg 《Progress in Photovoltaics: Research and Applications》2014,22(3):277-282
Triple‐junction solar cells from III–V compound semiconductors have thus far delivered the highest solar‐electric conversion efficiencies. Increasing the number of junctions generally offers the potential to reach even higher efficiencies, but material quality and the choice of bandgap energies turn out to be even more importance than the number of junctions. Several four‐junction solar cell architectures with optimum bandgap combination are found for lattice‐mismatched III–V semiconductors as high bandgap materials predominantly possess smaller lattice constant than low bandgap materials. Direct wafer bonding offers a new opportunity to combine such mismatched materials through a permanent, electrically conductive and optically transparent interface. In this work, a GaAs‐based top tandem solar cell structure was bonded to an InP‐based bottom tandem cell with a difference in lattice constant of 3.7%. The result is a GaInP/GaAs//GaInAsP/GaInAs four‐junction solar cell with a new record efficiency of 44.7% at 297‐times concentration of the AM1.5d (ASTM G173‐03) spectrum. This work demonstrates a successful pathway for reaching highest conversion efficiencies with III–V multi‐junction solar cells having four and in the future even more junctions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
926.
Mathias JD Tessier-Doyen N Michaud P 《International journal of molecular sciences》2011,12(2):1175-1186
Developing biofoams constitutes a challenging issue for several applications. The present study focuses on the development of a chitosan-based biofoam. Solutions of chitosan in acetic acid were dried under vacuum to generate foams with high-order structures. Chitosan concentration influenced significantly the morphology of developed porosity and the organization of pores in the material. Physico-chemical characterizations were performed to investigate the effects of chitosan concentration on density and thermal conductivity of foams. Even if chitosan-based biofoams exhibit interesting insulating properties (typically around 0.06 W·m(-1)·K(-1)), it has been shown that their durabilities are limited when submitted to a wet media. So, a way of application consists to elaborate a ceramic material with open porosity from a slurry prepared with an organic solvent infiltrating the porous network of the foam. 相似文献
927.
928.
Didier Saury Nicolas RougerFrancis Djanna François Penot 《International Communications in Heat and Mass Transfer》2011,38(6):679-687
A large-scale experimental setup is built and instrumented. It consists in a 4 m-high cavity with a horizontal cross-section equal to 0.86 × 1.00 m². Two opposite vertical walls are heated and cooled down; other walls (lateral walls, ceiling and floor) are made of insulating medium covered with a thin and low-emissivity film designed to minimize radiative effects into the cavity. The temperatures of active walls are imposed, constant and equally distributed around the ambient temperature in order to reduce heat losses. The temperature difference between the hot and cold walls is chosen to respect the Boussinesq approximation. Under these assumptions, Rayleigh number values up to 1.2 × 1011 (ΔT = 20 °C) can be obtained. The centre-symmetry is verified on the thermal stratification. Influence of the temperature difference and of wall emissivities on the stratification parameter (dimensionless vertical temperature gradient) is discussed. Velocity measurements allow the velocity field to be obtained and provide information on flows encountered in the cavity. Temperature measurements are also carried out in the whole cavity. In the paper, a complete experimental characterization is provided: airflow inside the cavity is analyzed and the Nusselt number along the hot and the cold wall is presented. 相似文献
929.
Chang HS Um W Rod K Serne RJ Thompson A Perdrial N Steefel CI Chorover J 《Environmental science & technology》2011,45(19):8313-8320
Leaching behavior of Sr and Cs in the vadose zone of Hanford site (Washington) was studied with laboratory-weathered sediments mimicking realistic conditions beneath the leaking radioactive waste storage tanks. Unsaturated column leaching experiments were conducted using background Hanford pore water focused on first 200 pore volumes. The weathered sediments were prepared by 6 months reaction with a synthetic Hanford tank waste leachate containing Sr and Cs (10(-5) and 10(-3) molal representative of LO- and HI-sediment, respectively) as surrogates for (90)Sr and (137)Cs. The mineral composition of the weathered sediments showed that zeolite (chabazite-type) and feldspathoid (sodalite-type) were the major byproducts but different contents depending on the weathering conditions. Reactive transport modeling indicated that Cs leaching was controlled by ion-exchange, while Sr release was affected primarily by dissolution of the secondary minerals. The later release of K, Al, and Si from the HI-column indicated the additional dissolution of a more crystalline mineral (cancrinite-type). A two-site ion-exchange model successfully simulated the Cs release from the LO-column. However, a three-site ion-exchange model was needed for the HI-column. The study implied that the weathering conditions greatly impact the speciation of the secondary minerals and leaching behavior of sequestrated Sr and Cs. 相似文献
930.
Abstract: Addition of wheat bran to flours modifies their expansion properties after cooking extrusion. This can be attributed to changes in the melt shear viscosity at the die. The effect of wheat bran concentration added to achieve 2 levels of dietary fibers of 12. 6% and 24.4%, and process conditions on the shear viscosity of wheat flour was therefore assessed using an online twin‐slit rheometer. The shear viscosity measured at 30 s?1 ranged from 9.5 × 103 to 53.4 × 103 Pa s. Regardless of the process conditions and bran concentration, the extruded melts showed a pseudoplastic behavior with a power law index n ranging from 0.05 to 0.27. Increasing the barrel temperature of the extruder from 120 to 180 °C, the water content from 18% to 22% or the screw speed from 400 to 800 rpm significantly decreased the melt shear viscosity at the extruder exit. The addition of bran significantly increased the melt shear viscosity only at the highest bran concentration. The effect was process condition dependant. Mathematical interpretations, based upon observations, of the experimental data were carried out. They can be used to predict the effect of the process conditions on the melt shear viscosity at the die of extruded wheat flour with increasing bran concentration. The viscosity data will be applied in future works to study the expansion properties of extruded wheat flour supplemented with bran. Practical Application: Incorporation of wheat bran, a readily available and low cost by‐product, in extruded puffed foods is constrained due to its negative effect on the product texture. Understanding the effect of wheat bran on rheological properties of extruded melts, driving the final product properties, is essential to provide solutions to the food industry and enhance its use. 相似文献