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51.
The formation of Cu–alginate complexes and the impact of free or bound copper on the oxidative stability of model water/oil mixtures containing edible sunflower or corn oil were examined. Equilibrium dialysis showed that copper binding capacity of alginate increased proportionally with copper concentration and the binding was rapid. The results indicated that 25 mM CuCl2 was necessary in obtaining beads of spherical shape and adequate mechanical strength (0.45 N at 80% compression) to avoid rupture during mixing, whereas lower CuCl2 concentrations resulted in weak gel beads (0.34 N) of irregular shape. When Cu–alginate beads were dispersed in the aqueous phase to give 0.5 mM copper, the peroxide value of water/corn oil mixtures was 3.7 mEq peroxide/kg oil after 7 days. Corn oil-containing mixtures with 0.5 mM free Cu2+ in the aqueous phase had a peroxide value ∼3 times higher (P < 0.001) after the same storage time. However, copper binding by alginate did not significantly reduce the peroxide values of the water/sunflower oil mixtures. Results indicated that the binding of pro-oxidant minerals, such as copper, in alginate beads can reduce the levels of oxidation in water/oil mixtures. 相似文献
52.
Somà Aurelio Iamoni Sonia Voicu Rodica Müller Raluca Al-Zandi Muaiyd H. M. Wang Changhai 《Microsystem Technologies》2018,24(2):1053-1060
Microsystem Technologies - This paper presents the design, fabrication and experimental characterization of an electro-thermally actuated microgripper suitable for single-cell manipulation. The... 相似文献
53.
Raluca Dumitru Adelina Ianculescu Cornelia Păcurariu Lavinia Lupa Aniela Pop Bogdan Vasile Adrian Surdu Florica Manea 《Ceramics International》2019,45(2):2789-2802
Pure bismuth ferrite was successfully obtained through the thermolysis of new bismuth ferrioxalate coordination compound, namely BiFe(C2O4)3·3H2O. The synthesized precursor was characterized by chemical analysis, infrared spectroscopy and thermal analysis. The bismuth ferrite obtained after a heating treatment of the precursor for at 450–800?°C/1?h was investigated by X-ray diffraction, FE-SEM, TEM and HRTEM. The obtained pure bismuth ferrite nanoparticles (480?°C) was tested as photocatalyst towards the degradation of doxorubicin (DOX), a well-known anti-cancer drug commonly used for the treatment of various cancer types, which has been detected in hospital effluent water. The comparative results of DOX degradation through photolysis and photocatalysis under UV irradiation showed a great photocatalytic activity of bismuth ferrite towards DOX degradation and mineralization from water. The kinetics aspects were discussed based on the first-order kinetics model that fitted the best the experimental photocatalysis results. 相似文献
54.
Hanie Hashtroudi Rajesh Kumar Raluca Savu Stanislav Moshkalev Go Kawamura Atsunori Matsuda Mahnaz Shafiei 《International Journal of Hydrogen Energy》2021,46(10):7653-7665
A novel microwave assisted two-dimensional (2D) hybrid material based on nanostructured reduced graphene oxide (rGO) doped with Pd nanoparticles (Pd/rGO) has been synthesised to investigate its hydrogen sensing performance at different operational conditions. The sensing performance has been evaluated at various operating temperatures (room temperature up to 120 °C), hydrogen concentrations (up to 1%), and relative humidity (up to ~44%). The material characterization of the hybrid Pd/rGO analysed by different techniques which confirms homogeneous distribution of Pd NPs (<35 nm) on the multi-layered porous structure of the rGO nanosheets (NSs) and forming the hybrid Pd/rGO NSs. Moreover, the fundamental hydrogen sensing mechanism as well as recovery enhancement by ultraviolet (UV) light are investigated. This work offers an environmentally friendly and energy-saving synthesis approach for hydrogen sensing with excellent control over experimental parameters which can lead to fabrication of a highly selective and sensitive hydrogen sensor. 相似文献
55.
Ultrastructural evaluation of mesenchymal stem cells from inflamed periodontium in different in vitro conditions
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Raluca Zaganescu Emoke Pall Adrian Florea Alexandra Roman Andrada Soanca Carmen Mihaela Mihu 《Microscopy research and technique》2015,78(9):792-800
This research aimed to observe the behavior of mesenchymal stem cells (MSCs) isolated from periodontal granulation tissue (gt) when manipulated ex vivo to induce three‐dimensional (3D) spheroid (aggregates) formation as well as when seeded on two bone scaffolds of animal origin. Periodontal gt was chosen as a MSC source because of its availability, considering that it is eliminated as a waste material during conventional surgical therapies. 3D aggregates of cells were generated; they were grown for 3 and 7 days, respectively, and then prepared for transmission electron microscopic analysis. The two biomaterials were seeded for 72 h with gtMSCs and prepared for scanning electronic microscopic observation. The ultrastructural analysis of 3D spheroids remarked some differences between the inner and the outer cell layers, with a certain commitment observed at the inner cells. Both scaffolds showed a relatively smooth surface at low magnification. Macro‐ and micropores having a scarce distribution were observed on both bone substitutes. gtMSCs grew with relative difficulty on the biomaterials. After 72 h of proliferation, gtMSCs scarcely covered the surface of bovine bone scaffolds, demonstrating fibroblast‐like or star‐like shapes with elongated filiform extensions. Our results add other data on the possible usefulness of gtMSC and could question the current paradigm regarding the complete removal of chronically inflamed gts from the defects during periodontal surgeries. Until optimal protocols for ex vivo manipulation of MSCs are available for clinical settings, it is advisable to use biocompatible bone substitutes that allow the development of progenitor cells. Microsc. Res. Tech. 78:792–800, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
56.
Petrican Raluca; Burris Christopher T.; Bielak Tania; Schimmack Ulrich; Moscovitch Morris 《Canadian Metallurgical Quarterly》2011,100(6):1111
Perceived closeness that preserves the distinctness of each partner enhances intimate relationship quality, whereas pseudocloseness or enmeshment—reflecting an inability to distinguish one's own thoughts and emotions from a partner's—may have more negative outcomes (R. J. Green & P. D. Werner, 1996). Two studies investigated whether a dispositional inability to differentiate self from other is manifested at the attentional level as reduced capacity to inhibit following the gaze of another (A. Frischen, A. P. Bayliss, & S. P. Tipper, 2007). Among healthy elderly spouses in Study 1, superior gaze control predicted superior sociocognitive functioning, and those with poorer gaze control abilities were perceived by the partner as constricting the perceiving partner's autonomy, which in turn predicted lower relationship satisfaction among the latter. Moreover, these links were mediated by enmeshment, as indicated by the percentage of “we”-focused versus “I”- or partner-focused thoughts and emotions in the partners' independent accounts of the same relationship events. Extending these findings in a sample of Parkinson's disease patients and their spouses, Study 2 revealed a biphasic effect of self–other differentiation on relationship dynamics: In the early stages of the disease, increased couple focus promoted superior relationship quality, whereas lack of self–other differentiation predicted poorer relationship quality later. Thus, dispositional variations in fundamental social-perceptual processes predict both close relationship dynamics and long-term relationship quality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
57.
A Ardizzoni M Bonavia M Viale E Baldini C Mereu A Verna S Ferrini A Cinquegrana S Molinari GL Mariani 《Canadian Metallurgical Quarterly》1994,73(5):1353-1360
BACKGROUND: Interleukin-2 (IL-2) has shown antitumor activity in some neoplasms, such as melanoma and renal carcinoma, but toxicity derived from bolus administration is significant, particularly at the cardiorespiratory level. METHODS: To test feasibility, antitumor activity, pulmonary and systemic immunologic effects, and pulmonary function changes of continuous-infusion recombinant IL-2 given to patients with non-small cell lung cancer, eleven subjects with Stage III-IV disease were treated in a standard pulmonary medicine unit with a dose of 18 million IU/m2/day from day 1 to day 13 with 1-day rest on day 7. A second induction course was given after a 3-week rest. In patients with nonprogressive disease, four maintenance courses of 6 days' duration at the same dose were planned. Immunologic tests, including lymphocyte phenotype analysis and assays for the detection of tumor necrosis factor (TNF) and of anti-IL-2 antibodies, were performed before and after treatment in serum and bronchoalveolar lavage fluid (BAL). Cardiopulmonary function tests, including spirometry, arterial blood gas analysis, diffusion capacity, and echocardiography, were obtained before, during, and after treatment. RESULTS: Twenty-one cycles (15 induction courses plus 6 maintenance courses) were administered. No patient was able to complete the six planned courses, and only 3 patients entered the maintenance phase. Reasons for discontinuation included progressive disease in five cases, toxicity in three cases, and patient request in three cases. The most common side effects were fever, hypotension, oliguria, and elevated serum creatinine and liver enzyme levels. No patient required intubation or intensive care. No objective response was seen, and the median survival time was 10 months. Lymphocytosis and eosinophilia were observed in all patients. Surface marker analysis revealed a statistically significant increase in the percentage of CD3+, CD4+, CD25+ and DR+ cells in peripheral blood. Lymphoid cells derived from BAL disclosed an increased natural killer activity after IL-2 treatment, and TNF was increased in BAL fluid. Pulmonary function tests evidenced an increased alveolar-arterial difference for oxygen allied with a decrease of forced expiratory volume in 1 second, forced vital capacity, and carbon monoxide transfer coefficient consistent with a significant, albeit not clinically relevant, interstitial lung defect. CONCLUSION: Continuous-infusion IL-2 is feasible in patients with advanced lung cancer even outside an intensive care unit, but overall compliance is poor. Although clinical pulmonary toxicity is negligible, small but statistically significant alterations of the pulmonary function are evident. In addition, this regimen produces a significant activation of the immune system at the pulmonary level. 相似文献
58.
Julian S. Cashmore Marco Apolloni Antonio Braga Onur Caglar Valentina Cervetto Yves Fenner Stephanie Goldbach‐Aschemann Celine Goury Jochen E. Htzel Takashi Iwahashi Jiri Kalas Masayuki Kitamura Markus Klindworth Markus Kupich George‐Felix Leu Jun Lin Marie‐Helene Lindic Paolo A. Losio Tomas Mates Daisuke Matsunaga Bogdan Mereu Xuan‐Viet Nguyen Ioanna Psimoulis Sergej Ristau Tobias Roschek Aurel Salabas Elena Lorena Salabas Ivan Sinicco 《Progress in Photovoltaics: Research and Applications》2015,23(11):1441-1447
Mass‐adoption of thin‐film silicon (TF‐Si) photovoltaic modules as a renewable energy source can be viable if the cost of electricity production from the module is competitive with conventional energy solutions. Increased module performance (electrical power generated) is an approach to reduce this cost. Progress towards higher conversion efficiencies for ‘champion’ large area modules paves the way for mass‐production module performance to follow. At TEL Solar AG, Trübbach, Switzerland, significant progress in the absolute stabilized module conversion efficiency has been achieved through optimized solar cell design that integrates high‐quality amorphous and microcrystalline TF‐Si‐deposited materials with efficient light management and transparent conductive oxide layers in a tandem MICROMORPH™ module. This letter reports a world record large area (1.43 m2) stabilized module conversion efficiency of 12.34% certified by the European Solar Test Installation; an increase of more than 1.4% absolute compared with the previous record for a TF‐Si triple junction large area module. This breakthrough result generates more than 13.2% stabilized efficiency from each equivalent 1 cm2 of the active area of the full module. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
59.
Maria Bercea Simona Morariu Loredana Elena Nita Raluca Nicoleta Darie 《Polymer-Plastics Technology and Engineering》2013,52(13):1354-1361
The application of Pluronic F127 as injectable gel-forming solution is limited by poor mechanical properties. The purpose of this study was to develop low viscosity formulations at ambient temperature that undergo a transition to gel under physiological conditions. Mixtures of Pluronic F127 and poly(vinyl alcohol) with different compositions were prepared in aqueous solutions and their in-situ gelation was investigated by dynamic light scattering and rheology. The results obtained for different formulations showed synergistic effects of polymer mixtures in aqueous media and their properties can be tuned by varying polymer concentration, system composition or changing temperature. 相似文献
60.
Elena Stoleru Silvestru B. Munteanu Raluca P. Dumitriu Adina Coroaba Mioara Drobotă Lidija Fras Zemljic Gina M. Pricope Cornelia Vasile 《Iranian Polymer Journal》2016,25(4):295-307
A dual-bioactive layer based on antimicrobial chitosan and antioxidant vitamin E was immobilized onto PE surface using electrospraying as coating technique. Covalent bonding of the antibacterial/antioxidant layer was achieved through amide bonds or carbamate linkage using both 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride and N-hydroxysuccinimide or carbonyldiimidazole coupling agents, respectively. The chitosan/vitamin E formulation was characterized by rheological measurements. The vitamin E addition in chitosan matrix leads to changes in chitosan rheological properties, such as viscosity decrease with increasing vitamin E content, change of the gel-like behavior to a fluid-like behavior, which further influences the electrospraying process and deposited coating morphology. The new stratified hybrid materials with improved properties have been characterized by different techniques as attenuated total reflectance-Fourier transform IR spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS), polyelectrolyte and potentiometric titration, contact angle titration, scanning electron microscopy (SEM) and antibacterial and antioxidative tests. The electrosprayed bioactive coatings exhibit antibacterial, antioxidant and pH responsive activity. The pH responsiveness was evidenced by switching from hydrophilic to hydrophobic surface at pH ≈ 6. The chitosan/vitamin E modified PE substrate inhibited the growth for three different bacterial strains (Gram-negative and Gram-positive) and presented good antioxidative properties, acting as DPPH radical scavenging surfaces. Moreover, the new obtained materials present good stability and maintain their antioxidative capacity even after subjecting to desorption in harsh medium because of relative strong electrostatic and hydrogen bonds interactions between components of the formulation. The obtained materials can find application in food packaging or in medical field where synergistic action of these bioactive compounds is required. 相似文献