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31.
Sergiu Cecoltan Izabela-Cristina Stancu Diana Maria Drăguşin Andrada Serafim Adriana Lungu Cătălin Ţucureanu Iuliana Caraş Vlad Constantin Tofan Aurora Sălăgeanu Eugeniu Vasile Romain Mallet Daniel Chappard Cristin Coman Mircea Istodorescu Horia Iovu 《Journal of materials science. Materials in medicine》2017,28(10):153
32.
Daniel E. Azofeifa Neville Clark William E. Vargas Hugo Solis E. Avendano Michael Cambronero Diana Valverde-Mendez 《International Journal of Hydrogen Energy》2017,42(35):22373-22378
We report measurements of the optical transmission, between 240 and 1040 nm, and electrical resistivity of polycrystalline zirconium thin films as they absorb hydrogen. Both are measured as H2 pressure is increased up to 880 mbar, at room temperature. Films, 20–22 nm thick, are deposited on fused quartz substrates by e-beam evaporation at 5.3 × 10?7 mbar base pressure and covered with a 8.0 nm Pd over-coat. The morphology of the films is studied by means of AFM images. The complex refractive indices of Zr and Pd are extracted numerically from the transmission spectra by using a spectral projected gradient method for different hydrogen pressures. The corresponding dielectric functions for various Zr hydrogen concentrations are described with the parametric Drude-Lorentz and Brendel-Bormann (DL & BB) models. The Acceptance-Probability-Controlled Simulated Annealing approach is applied to calculate the parameters of the DL & BB model. This allows us to describe the effect of increasing hydrogen absorption on these parameters and in derived quantities, like the relaxation time and the effective mass of conduction electrons, the electrical resistance, the Fermi energy, and the electronic density of states at the Fermi level. 相似文献
33.
Nanoparticulate Delivery of Cancer Cell Membrane Elicits Multiantigenic Antitumor Immunity 下载免费PDF全文
Ashley V. Kroll Ronnie H. Fang Yao Jiang Jiarong Zhou Xiaoli Wei Chun Lai Yu Jie Gao Brian T. Luk Diana Dehaini Weiwei Gao Liangfang Zhang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(47)
Anticancer vaccines train the body's own immune system to recognize and eliminate malignant cells based on differential antigen expression. While conceptually attractive, clinical efficacy is lacking given several key challenges stemming from the similarities between cancerous and healthy tissue. Ideally, an effective vaccine formulation would deliver multiple tumor antigens in a fashion that potently stimulates endogenous immune responses against those antigens. Here, it is reported on the fabrication of a biomimetic, nanoparticulate anticancer vaccine that is capable of delivering autologously derived tumor antigen material together with a highly immunostimulatory adjuvant. The two major components, tumor antigens and adjuvant, are presented concurrently in a fashion that maximizes their ability to promote effective antigen presentation and activation of downstream immune processes. Ultimately, it is demonstrated that the formulation can elicit potent antitumor immune responses in vivo. When combined with additional immunotherapies such as checkpoint blockades, the nanovaccine demonstrates substantial therapeutic effect. Overall, the work represents the rational application of nanotechnology for immunoengineering and can provide a blueprint for the future development of personalized, autologous anticancer vaccines with broad applicability. 相似文献
34.
Killeen Peter R.; Posadas-Sanchez Diana; Johansen Espen Borg?; Thrailkill Eric A. 《Canadian Metallurgical Quarterly》2009,35(1):35
[Correction Notice: An erratum for this article was reported in Vol 35(2) of Journal of Experimental Psychology: Animal Behavior Processes (see record 2009-05154-003). The URL provided for the supplemental material was incomplete. The complete URL is http://dx.doi.org/10.1037/a0012497.supp] Pigeons' pecks produced grain under progressive ratio (PR) schedules, whose response requirements increased systematically within sessions. Experiment 1 compared arithmetic (AP) and geometric (GP) progressions. Response rates increased as a function of the component ratio requirement, then decreased linearly (AP) or asymptotically (GP). Experiment 2 found the linear decrease in AP rates to be relatively independent of step size. Experiment 3 showed pausing to be controlled by the prior component length, which predicted the differences between PR and regressive ratio schedules found in Experiment 4. When the longest component ratios were signaled by different key colors, rates at moderate ratios increased, demonstrating control by forthcoming context. Models for response rate and pause duration based on Bizo and Killeen (1997) described performance on AP schedules; GP schedules required an additional parameter representing the contextual reinforcement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Bor‐Sen Chiou Diana Valenzuela‐Medina Mark Wechsler Cristina Bilbao‐Sainz Artur K. Klamczynski Tina G. Williams Delilah F. Wood Greg M. Glenn William J. Orts 《应用聚合物科学杂志》2015,132(10)
Torrefied almond shells and wood chips were incorporated into polypropylene as fillers to produce torrefied biomass‐polymer composites. The composites were prepared by extrusion and injection molding. Response surface methodology was used to examine the effects of filler concentration, filler size, and lignin factor (relative lignin to cellulose concentration) on the material properties of the composites. The heat distortion temperatures, thermal properties, and tensile properties of the composites were characterized by thermomechanical analysis, differential scanning calorimetry, and tensile tests, respectively. The torrefied biomass composites had heat distortion temperatures of 8–24°C higher than that of neat polypropylene. This was due to the torrefied biomass restricting mobility of polypropylene chains, leading to higher temperatures for deformation. The incorporation of torrefied biomass generally resulted in an increase in glass transition temperature, but did not affect melting temperature. Also, the composites had lower tensile strength and elongation at break values than those of neat polypropylene, indicating weak adhesion between torrefied biomass and polypropylene. However, scanning electron microscopy results did indicate some adhesion between torrefied biomass and polypropylene. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41582. 相似文献
36.
The concepts of both duality and fuzzy uncertainty in linear programming have been theoretically analyzed and comprehensively and practically applied in an abundance of cases. Consequently, their joint application is highly appealing for both scholars and practitioners. However, the literature contributions on duality in fuzzy linear programming (FLP) are neither complete nor consistent. For example, there are no consistent concepts of weak duality and strong duality. The contributions of this survey are (1) to provide the first comprehensive overview of literature results on duality in FLP, (2) to analyze these results in terms of research gaps in FLP duality theory, and (3) to show avenues for further research. We systematically analyze duality in fuzzy linear programming along potential fuzzifications of linear programs (fuzzy classes) and along fuzzy order operators. Our results show that research on FLP duality is fragmented along both dimensions; more specifically, duality approaches and related results vary in terms of homogeneity, completeness, consistency with crisp duality, and complexity. Fuzzy linear programming is still far away from a unifying theory as we know it from crisp linear programming. We suggest further research directions, including the suggestion of comprehensive duality theories for specific fuzzy classes while dispensing with restrictive mathematical assumptions, the development of consistent duality theories for specific fuzzy order operators, and the proposition of a unifying fuzzy duality theory. 相似文献
37.
Chemical Composition and Physical Properties of High Oleic Safflower Oils (Carthamus tinctorius,Var. CW88-OL and CW99-OL) 下载免费PDF全文
Florencia Salaberría Diana Constenla Amalia A. Carelli María E. Carrín 《Journal of the American Oil Chemists' Society》2016,93(10):1383-1391
Chemical composition and physical properties of CW88‐OL and CW99‐OL cultivars of high oleic safflower seeds and their hexane‐extracted oils were determined. Dry‐based seed composition of CW88‐OL and CW99‐OL was: moisture = 4.29 and 4.23 %, oil = 42.29 and 46.44 %, Crude protein = 20.94 and 16.41 %, neutral detergent fiber = 28.11 and 28.49 %, ash = 1.55 and 2.01 %, phosphorus content = 2033 and 3995 mg/kg, respectively. Major fatty acids in oils were ~78 % oleic (O), ~13 % linoleic (L), ~5 % palmitic (P) and ~2 % stearic (St) acids, for both cultivars. The main triacylglycerols were OOO (~50 %), OOL (~20 %), SOL + OPO (~10 %), and LLP (~5 %). The oil composition of CW88‐OL and CW99‐OL in main minor components was: α‐tocopherol = 582 and 551 mg/kg, total sterols = 3996 and 3362 mg/kg, phospholipids = 22 and 21 mg/kg and wax content = 70 and 74 mg/kg. For both cultivars, density and viscosity of the oils between 25 and 55 °C varied from 903.4 to 912.6 kg/m3 and 63 to 23 mPa.s showing linear and exponential behaviors, respectively. The refractive index was 1.4694. The CIELab color parameters were: 89.69 and 89.53 (L*), ?3.72 and ?3.07 (a*), and 47.28 and 47.78 (b*) (CW88‐OL and CW99‐OL, respectively). Thus, the high oil content of the seeds and nutritional quality of the oil accompanied by low levels of waxes and phospholipids makes the cultivars studied promising for producers and consumers. 相似文献
38.
Damin M Maestri Diana O Labuckas Alicia L Lamarque Julio A Zygadlo Nelson R Grosso María J Martínez Carlos A Guzmn 《Journal of the science of food and agriculture》1996,70(3):334-336
Seeds of 11 sorghum cultivars ( Sorghum bicolor ) from Argentina were analysed for proximate composition, fatty acids and sterols. Oil, protein, carbohydrate and ash contents varied between 41 and 66 g kg−1, 111 and 156 g kg−1, 670 and 730 g kg−1 and 13·8 and 20·6 g kg−1 of dry matter, respectively. Fatty acid profiles revealed that the major acids were palmitic (15·1–24·8%), oleic (29·9–41·8%) and linoleic (35·9–51·3%). Unsaponifiable matter was examined for sterols. Sitosterol was the prominent component in all cultivars (43·8–57·9%), followed by campesterol (18·7–29·1%) and stigmasterol (12·4–20·5%). 相似文献
39.
Diana Salvador Vernica Bastos Helena Oliveira 《International journal of molecular sciences》2022,23(1)
Melanoma is the deadliest form of skin cancer, and its incidence has alarmingly increased in the last few decades, creating a need for novel treatment approaches. Thus, we evaluated the combinatorial effect of doxorubicin (DOX) and hyperthermia on A375 and MNT-1 human melanoma cell lines. Cells were treated with DOX for 24, 48, and 72 h and their viabilities were assessed. The effect of DOX IC10 and IC20 (combined at 43 °C for 30, 60, and 120 min) on cell viability was further analyzed. Interference on cell cycle dynamics, reactive oxygen species (ROS) production, and apoptosis upon treatment (with 30 min at 43 °C and DOX at the IC20 for 48 h) were analyzed by flow cytometry. Combined treatment significantly decreased cell viability, but not in all tested conditions, suggesting that the effect depends on the drug concentration and heat treatment duration. Combined treatment also mediated a G2/M phase arrest in both cell lines, as well as increasing ROS levels. Additionally, it induced early apoptosis in MNT-1 cells, while in A375 cells this effect was similar to the one caused by hyperthermia alone. These findings demonstrate that hyperthermia enhances DOX effect through cell cycle arrest, oxidative stress, and apoptotic cell death. 相似文献
40.
Paul-Mihai Boarescu Ioana Boarescu Raluca Maria Pop tefan Horia Roian Ioana Corina Bocan Vasile Rus Rzvan Olimpiu Mada Iulia Diana Popa Nicholas Neagu Adriana Elena Bulboac Anca Dana Buzoianu Sorana D. Bolboac 《International journal of molecular sciences》2022,23(3)
The present study aims to compare the oxidative stress biomarkers, pro-inflammatory cytokines, and histological changes induced by three cardiovascular risk factors, namely, hypertension, dyslipidemia, and type 1 diabetes mellitus. Hypertension was induced with 40 mg/kg body weight (b.w.) of N omega-nitro-L-arginine-methyl (L-NAME) administered orally. Dyslipidemia was induced by the administration of a diet with a high cholesterol (2%) content. Diabetes mellitus was induced by intraperitoneal administration of a single dose of streptozocin (65 mg/kg). Malondialdehyde (MDA) and total oxidative status (TOS) are increased by all three cardiovascular risk factors (up to 207%). The indirect assessment of NO synthesis (NOx) is observed to be reduced after L-NAME administration (43%), and dyslipidemia induction (16%), while type 1 diabetes mellitus is associated with the highest levels of NOx (increased 112%). Hypertension, dyslipidemia, and type 1 diabetes reduced the total antioxidative capacity (TAC) and total thiol (SH) levels (up to 57%). The values of evaluated pro-inflammatory cytokines, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), assessed from the ascending aorta were elevated by all three cardiovascular risk factors, with the highest levels induced by type 1 diabetes mellitus (up to 259%). The histopathological examination of the ascending and descending aorta revealed reversible pro-atherogenic changes consisting of the accumulation of lipid droplets in the subendothelial connective tissue on rats with hypertension and dyslipidemia. Irreversible pro-atherogenic changes consisting of a reduction of the specific elasticity of the arteries were observed in rats with type 1 diabetes mellitus. Type 1 diabetes mellitus demonstrates an alteration of the oxidative stress parameters, the elevation of tissue levels of the pro-inflammatory cytokines and causing irreversible pro-atherogenic changes on the aortic wall. 相似文献