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41.
Christopher J. Wilson Henny Volders Marianna Pantouvaki Alton B. Horsfall Zsolt T?kei 《Microelectronic Engineering》2010,87(3):398-401
An in situ study of self-forming barriers from a Cu-Mn alloy was performed to investigate the barrier growth using X-ray diffraction on damascene lines. The associated evolution in interconnect texture and Cu stress was also observed. The shift in Cu diffraction peak position was used to determine the change in Mn concentration and hence, estimate the thickness of the MnSixOy barrier. The observed peak shift followed a log(t) behaviour and is described well by metal oxidation kinetics, following the field enhanced diffusion model. We used multiple anneal temperatures to study the activation of the formation process, demonstrating a faster barrier formation with higher ion excitation. A strong [1 1 1] Cu texture was shown to develop during the anneal in contrast to traditional PVD barrier systems. Finally, the stress in the 100 nm Cu lines was calculated, observing a large in-plane relaxation when using a self-forming barrier due to reduced confinement. 相似文献
42.
Marianna N. Xanthopoulou Tzortzis Nomikos Elizabeth Fragopoulou Smaragdi Antonopoulou 《Food research international (Ottawa, Ont.)》2009,42(5-6):641-646
Pumpkin seeds have been implicated in providing health benefits. However their antioxidant or anti-inflammatory activity of their extracts has never been studied. Therefore, four commercially available pumpkin seeds were treated with two different extraction methodologies in order to obtain fractions with different content. The extracts were screened for their antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and for their inhibitory activity against lipid peroxidation catalyzed by soybean lipoxygenase.Most extracts tested have demonstrated radical scavenging activity, which depends on their total phenolic content, with fractions rich in phenolics showing the strongest activity. On the other hand, the phenolic content of extracts does not determine their activity against lipoxygenase, as acetone and polar lipid fractions are its strongest inhibitors. The presence of molecules being able to scavenge radicals and inhibit lipoxygenase in pumpkin seeds may in part explain the health benefits attributed to them. 相似文献
43.
To study the structure of grains of suspension poly(vinyl chloride) (PVC), the authors applied a capillary viscometer for cyclic measurements of viscosity of the PVC–cyclohexanone solution during dissolution of the polymer. Final concentration of the solution was 0.5–1.0 g/100 cm3 and the measurements were made at temperatures of 313, 333, 353, and 373 K. It was found that at 353 K, a temperature close to the glass transition temperature of PVC, the curve describing changes of viscosity vs. the dissolution time has a pronounced maximum. It follows from a preliminary analysis of the obtained results that this maximum corresponds to the viscosity of a PVC solution in which average apparent mass is many times larger than true average molecular mass of the studied sample. It mans that into the solution enter single chains and some formations, called microdomains in the literature, that are composed of tens of macromolecules. The microdomains disintegrate later to single macromolecules. 相似文献
44.
Veronica Dimuccio Linda Bellucci Marianna Genta Cristina Grange Maria Felice Brizzi Maddalena Gili Sara Gallo Maria Laura Centomo Federica Collino Benedetta Bussolati 《International journal of molecular sciences》2022,23(20)
Simple SummaryDiabetic nephropathy is one of the most frequent complications of diabetes, resulting from diffuse damage to different kidney cells. The identification of subjects at risk is mandatory to prevent its development and provide appropriate therapies reducing the unmanageable evolution towards end-stage kidney disease. The aim of this work was to identify urinary-derived extracellular vesicles (EVs) miRNA cargo to be used as biomarker of kidney damage in diabetic patients. The miRNA profile was then correlated with the molecular mechanism associated with the glomerular and tubular damage using a diabetic-like model. In patients, miR145 and miR126 in urinary EVs increased together with albuminuria. MiR145 and miR126 increased in parallel in EVs from renal epithelial cells undergoing transition to a fibrotic mesenchymal phenotype. These data unveiled a role for miR126 and miR145 as the biomarkers of damage progression and proteinuria development in diabetic nephropathy. AbstractDiabetic nephropathy (DN) is a severe kidney-related complication of type 1 and type 2 diabetes and the most frequent cause of end-stage kidney disease. Extracellular vesicles (EVs) present in the urine mainly derive from the cells of the nephron, thus representing an interesting tool mirroring the kidney’s physiological state. In search of the biomarkers of disease progression, we here assessed a panel of urinary EV miRNAs previously related to DN in type 2 diabetic patients stratified based on proteinuria levels. We found that during DN progression, miR145 and miR126 specifically increased in urinary EVs from diabetic patients together with albuminuria. In vitro, miRNA modulation was assessed in a model of TGF-β1-induced glomerular damage within a three-dimensional perfusion system, as well as in a model of tubular damage induced by albumin and glucose overload. Both renal tubular cells and podocytes undergoing epithelial to mesenchymal transition released EVs containing increased miR145 and miR126 levels. At the same time, miR126 levels were reduced in EVs released by glomerular endothelial cells. This work highlights a modulation of miR126 and miR145 during the progression of kidney damage in diabetes as biomarkers of epithelial to mesenchymal transition. 相似文献
45.
Barbara G. Delano Marianna S. Markell Frieda Wolf Ejiro Ugova Eli A. Friedman Moro O. Salifu 《Hemodialysis international. International Symposium on Home Hemodialysis》2002,6(1):54-57
There is limited use of home renal replacement therapies in the U.S.A. One percent of dialysis patients are on home hemodialysis (HHD) and only 9% undergo peritoneal dialysis (PD). In an effort to better understand this, 161 satellite hemodialysis patients in 6 units in Brooklyn were surveyed. Forty‐eight percent of patients were women, 86% were black, 5% white, 8% Hispanic, and 1% other. Mean age was 49.4 years (range 22 – 69 years). Etiology of renal disease was hypertension (41%), diabetes mellitus (31%), polycystic kidney disease (3%), systemic lupus erythematosus (4%), and other or unknown (21%). Patients were queried about knowledge of and attitudes toward home therapies. Seventy‐nine percent of patients knew of home dialysis. The source of this information was the nephrologist (59%), the social worker (14%), a nurse (8%), other patients (4%), and other sources (15%). Only 10% of patients had ever considered HHD. Fifty‐four percent were afraid to do self‐care at home and 35% were not interested. Surprisingly, only 3% felt they had no reliable helper and 8% felt that their housing was not suitable. Similarly, 78% of patients had been spoken to about PD, but only 11% had considered it. Forty‐one percent were afraid of doing self‐care on PD, and 45% were not interested. We conclude that, although the majority of patients in six inner‐city dialysis units had heard of home dialysis, only a small number ever considered it. As many patients were afraid of doing home therapy, better education about the risks and benefits needs to be disseminated. 相似文献
46.
Marianna A. Shubov 《Canadian Metallurgical Quarterly》2006,19(1):1-12
The present paper is the last part of a three-part survey paper, in which I give a review of several research directions in the area of mathematical analysis of flutter phenomenon. Flutter is known as a structural dynamical instability, which occurs in a solid elastic structure interacting with a flow of gas or fluid and consists of violent vibrations of the structure with rapidly increasing amplitudes. The focus of this paper is a collection of models of fluid-structure interaction, for which precise mathematical formulations are available. My main interest is in the analytical results on such models: the results that can be used to explain flutter and its qualitative and even quantitative treatments. This study does not pretend to be a comprehensive review of an enormous engineering literature on analytical, computational, and experimental aspects of the flutter problem. I present a brief exposition of the results obtained in several selected papers or groups of papers. In this paper, I concentrate on the most well-known cases of flutter, i.e., flutter in aeroelasticity. Namely, I discuss aircraft flutter in historical retrospective and outline some future directions of flutter analysis. The last two sections of the paper are devoted to the precise analytical results obtained in my several recent works on a specific aircraft wing model in a subsonic, inviscid, incompressible airflow. I also mention that in the previous papers (Parts I and II of the survey), I discuss such topics as: (1) bending–torsion vibrations of coupled beams; (2) flutter in transmission lines; (3) flutter in rotating blades; (4) flutter in hard disk drives; (5) flutter in suspension bridges; and (6) flutter of blood vessel walls. 相似文献
47.
Michael D. Peck Emilio Mantero-Atienza Maria Jose Miguez-Burbano Mary Ann Fletcher Gail Shor-Posner Marianna K. Baum 《Lipids》1993,28(10):961
The online version of the original article can be found at 相似文献
48.
Antonio Bevilacqua Marianne Perricone Marianna Cannarsi Maria Rosaria Corbo & Milena Sinigaglia 《International Journal of Food Science & Technology》2009,44(11):2198-2207
This study focused to investigate the technological significance and the spoiling impact of diverse yeast strains, isolated from 'Bella di Cerignola' Italian table olives. Sixty-four isolates (belonging mainly to the species Candida famata and C. guilliermondii ) were studied to assess their growth at different temperatures (15, 25 and 37 °C), pHs (4.0, 5.0 and 9.5) and NaCl concentrations (0–10.0%) in lab medium. Their pectolytic, xylanolytic, lipolytic and catalase activities were also evaluated. Most of the yeasts showed a moderate pectolytic activity and were able to grow at pH 9.5 after 120 h of incubation. Salt and temperature were the most important environmental variables affecting yeast growth, which could exert a strong selective pressure on yeast population. Candida guilliermondii appeared more resistant to high salt concentrations, whereas C. famata was able to grow at 15 °C. 相似文献
49.
Marianna Mastromatteo Annalisa Lucera Milena Sinigaglia Maria Rosaria Corbo 《International Journal of Food Science & Technology》2009,44(12):2620-2628
Microbial characteristics under different atmospheres (vacuum, air, MAP1: 80% O2/20% CO2 and MAP2: 5% O2/65% N2/30% CO2) of poultry patties made of a mixture of ostrich, chicken and turkey meat were evaluated. The meat preparations were examined for changes in pH, colour properties (CIE L*, a*, b*), headspace composition, and bacterial counts (total viable cell, psychrotrophs, Enterobacteriaceae, lactic acid bacteria, Staphylococcus spp., Brochothrix thermosphacta, Pseudomonas spp.). The use of a high O2 atmosphere (MAP1) quickly leads to a loss of the appealing red colour. A limited alteration occurred with use of MAP2 and vacuum. For total viable counts a cell load higher than 8 log cfu g?1 for the samples packaged in air, MAP1 and MAP2 at the end of storage was observed. Whereas, for the vacuum packed samples the cell load never reached values higher than 8 log cfu g?1. Enterobacteriaceae, B. thermosphacta and Pseudomonas spp. cell load was less with the vacuum (7.60, 5.06 and 7.17 log cfu g?1, respectively) and MAP2 packaging (7.08, 5.60 and 7.40 log cfu g?1, respectively). However, the high microbial loads suggest that an improvement of the microbiological quality of poultry meat is necessary if the producers are going to propose this new meat preparation on the market. 相似文献
50.
Antonio Bevilacqua Marianna Cannarsi Mariangela Gallo Milena Sinigaglia Maria Rosaria Corbo 《Journal of food science》2010,75(1):M53-M60
ABSTRACT: Enterobacter cloacae can be recovered in the spontaneous fermentations of Italian table olives. In this study, the effects of salt (20 to 100 g/L), temperature (10 to 37 °C), pH (4 to 5 and 8 to 10), p -coumaric and vanillic acids (0.5 to 2 g/L), and the acidification of the medium through lactic, citric, and ascorbic acids were investigated on 15 strains of E. cloacae , isolated from Italian table olives "Bella di Cerignola." Finally, a confirmatory experiment in synthetic brine was run. The strains were inhibited only by an NaCl amount of 70 to 80 g/L and by p -coumaric acid; on the other hand, they showed the ability to grow also at low temperatures (10 to 15 °C). The confirmatory experiment highlighted their ability to survive both at 15 °C and at pH 5. Enterobacter cloacae could be a real problem for the fermentation of table olives in southern Italy; some hurdles could be used (salt or brine acidification), but some environmental conditions (for example, the temperature) should be controlled carefully to maintain olive safety at acceptable levels. 相似文献