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151.
Maria Luisa Grilli Daniele Valerini Anca Elena Slobozeanu Bogdan O. Postolnyi Sebastian Balos Antonella Rizzo Radu Robert Piticescu 《Materials》2021,14(7)
Several applications, where extreme conditions occur, require the use of alloys often containing many critical elements. Due to the ever increasing prices of critical raw materials (CRMs) linked to their high supply risk, and because of their fundamental and large utilization in high tech products and applications, it is extremely important to find viable solutions to save CRMs usage. Apart from increasing processes’ efficiency, substitution, and recycling, one of the alternatives to preserve an alloy and increase its operating lifetime, thus saving the CRMs needed for its manufacturing, is to protect it by a suitable coating or a surface treatment. This review presents the most recent trends in coatings for application in high temperature alloys for aerospace engines. CRMs’ current and future saving scenarios in the alloys and coatings for the aerospace engine are also discussed. The overarching aim of this paper is to raise awareness on the CRMs issue related to the alloys and coating for aerospace, suggesting some mitigation measures without having the ambition nor to give a complete overview of the topic nor a turnkey solution. 相似文献
152.
Ribatti D Crivellato E Candussio L Vacca A Nico B Benagiano V Roncali L Dammacco F 《Haematologica》2002,87(5):465-471
BACKGROUND AND OBJECTIVES: Many data suggest that the density of mast cells (MC) is strongly correlated with the extent of both normal and pathologic angiogenesis, such as the vessel formation that occurs in chronic inflammatory diseases and tumors. We have previously demonstrated that isolated MC and their secretory granules, but not degranulated MC, induce an angiogenic response in the chick embryo chorioallantoic membrane (CAM) assay. DESIGN AND METHODS: The aim of this study was to investigate whether pre-treatment of MC with an anti-angiogenic molecule, namely recombinant human interferon-alpha2a (rhIFN-alpha2a), reduced the angiogenic activity of their conditioned media (CM) in the CAM assay. RESULTS: Our data indicate that rhIFN-alpha2a at 500-1000 IU is able to reduce the angiogenic activity of CM significantly. When MC were treated with rhIFN-alpha2a at 25-250 IU they retained their angiogenic activity. Addition of anti-fibroblast growth factor-2 (FGF-2) antibodies (but not anti-vascular endothelial growth factor) substantially reduced the angiogenic activity of CM treated with sub-optimal concentrations of rhIFN-alpha2a. INTERPRETATION AND CONCLUSIONS: FGF-2 may be the main angiogenic factor secreted by MC and higher concentrations of rhIFN-alpha2a possibly inhibit angiogenesis by blocking the actions of FGF-2 produced by MC. Finally, the morphologic features of MC treated with rhIFN-alpha2a, characterized by an atypical secretory pathway, are compatible with a slow release of the angiogenic cytokines stored in MC granules. 相似文献
153.
Major histocompatibility complex gene mapping in the amphibian Xenopus implies a primordial organization 下载免费PDF全文
154.
Asselta R Spena S Duga S Peyvandi F Malcovati M Mannucci PM Tenchini ML 《Haematologica》2002,87(8):855-859
BACKGROUND AND OBJECTIVES: Congenital afibrinogenemia is a rare coagulation disorder whose molecular basis is still poorly characterized. Most mutations have been identified in the fibrinogen Aalpha- and gamma-chain genes, whereas only two missense mutations have been reported in the Bbeta-chain gene. The aim of this work was to widen knowledge about the mutational spectrum of this disease by analyzing the molecular bases of congenital afibrinogenemia in three unrelated Iranian patients. DESIGN AND METHODS: All patients showed unmeasurable levels of clottable fibrinogen in plasma. Mutational screening was performed by sequencing the whole coding region, including exon-intron boundaries and part of the promoter region of the three fibrinogen genes. RESULTS: Sequencing in one patient revealed the presence of a novel nonsense mutation (3282C-->T) in exon 2 of the fibrinogen Bbeta-chain gene, causing a severe truncation of the corresponding polypeptide (R17X). In the remaining probands, two already known small deletions (4209delA and 4220delT), both located in exon 5 of the fibrinogen Aalpha-chain gene, were identified, and their effect at the protein level explored by computer-assisted analysis. INTERPRETATION AND CONCLUSIONS: The identification of the first truncating mutation in the fibrinogen Bbeta-chain gene confirms the involvement of all three fibrinogen genes in the pathogenesis of congenital afibrinogenemia and widens the mutational spectrum of the disease. This knowledge is clinically essential in order to carry out prenatal diagnosis in families at risk. 相似文献
155.
Bernaciak J Spina JC Curros ML Maya G Venditti J Chacon C 《Seminars in respiratory and critical care medicine》2002,23(6):597-600
A 48-year-old woman underwent surgery for a lesion seen on ultrasound and interpreted as a uterine myoma. The surgery revealed multiple nodules that had seeded on the omentum, peritoneum, and ovaries. The macroscopic interpretation was either metastasis or tuberculosis. The biopsy showed noncaseating granulomas, and a diagnosis of peritoneal sarcoidosis was reported. The AFB (acid fast bacillus) and L?wenstein-Jensen culture were negative. She was treated with methylprednisolone for 1 year for pulmonary sarcoidosis progression, with a resulting decrease in her DLCO (diffusing lung capacity for carbon monoxide). Computed tomography showed only a slight decrease in the multiple nodules and cysts. She is currently symptom-free. 相似文献
156.
Simona Puzelli Giada Rossini Marzia Facchini Gabriele Vaccari Livia Di Trani Angela Di Martino Paolo Gaibani Caterina Vocale Giovanni Cattoli Michael Bennett John W. McCauley Giovanni Rezza Maria Luisa Moro Roberto Rangoni Alba Carola Finarelli Maria Paola Landini Maria Rita Castrucci Isabella Donatelli the Influenza Task Force 《Emerging infectious diseases》2014,20(10):1745-1749
During an influenza A(H7N7) virus outbreak among poultry in Italy during August–September 2013, infection with a highly pathogenic A(H7N7) avian influenza virus was diagnosed for 3 poultry workers with conjunctivitis. Genetic analyses revealed that the viruses from the humans were closely related to those from chickens on affected farms. 相似文献
157.
Alessandra Ferramosca Annalea Conte Fabrizio Damiano Luisa Siculella Vincenzo Zara 《European journal of nutrition》2014,53(4):1103-1114
Purpose
Hepatic fatty acid synthesis is influenced by several nutritional and hormonal factors. In this study, we have investigated the effects of distinct experimental diets enriched in carbohydrate or in fat on hepatic lipogenesis.Methods
Male Wistar rats were divided into four groups and fed distinct experimental diets enriched in carbohydrates (70 % w/w) or in fat (20 and 35 % w/w). Activity and expression of the mitochondrial citrate carrier and of the cytosolic enzymes acetyl-CoA carboxylase and fatty acid synthetase were analyzed through the study with assessments at 0, 1, 2, 4, and 6 weeks. Liver lipids and plasma levels of lipids, glucose, and insulin were assayed in parallel.Results
Whereas the high-carbohydrate diet moderately stimulated hepatic lipogenesis, a strong inhibition of this anabolic pathway was found in animals fed high-fat diets. This inhibition was time-dependent and concentration-dependent. Moreover, whereas the high-carbohydrate diet induced an increase in plasma triglycerides, the high-fat diets determined an accumulation of triglycerides in liver. An increase in the plasmatic levels of glucose and insulin was observed in all cases.Conclusions
The excess of sucrose in the diet is converted into fat that is distributed by bloodstream in the organism in the form of circulating triglycerides. On the other hand, a high amount of dietary fat caused a strong inhibition of lipogenesis and a concomitant increase in the level of hepatic lipids, thereby highlighting, in these conditions, the role of liver as a reservoir of exogenous fat. 相似文献158.
159.
Alcohol Use Behaviors Among Indigenous Migrants: A Transnational Study on Communities of Origin and Destination 总被引:1,自引:0,他引:1
Miguel Pinedo Yasmin Campos Daniela Leal Julio Fregoso Shira M. Goldenberg María Luisa Zúñiga 《Journal of immigrant and minority health / Center for Minority Public Health》2014,16(3):348-355
The association between international and domestic migration and alcohol use among indigenous communities is poorly understood. We explored migration-related factors associated with alcohol use behaviors among an indigenous Mayan, binational population. From January to March 2012, 650 indigenous participants from the high-emigration town of Tunkás in the Mexican state of Yucatán (n = 650) residing in Mexico and California completed surveys. Multivariate logistic regression identified migration-related factors associated with alcohol use behaviors. US migration of shorter duration (<5 years) was independently associated with at-risk drinking (adjusted odds ratio (AOR) 2.34; 95 % confidence interval (CI) 1.09–5.03), as was longer-duration domestic migration (≥5 years) (AOR 2.34; 95 % CI 1.12–4.87). Ability to speak Maya (AOR 0.26; 95 % CI 0.13–0.48) was protective against at-risk drinking. Culturally appropriate alcohol use prevention interventions are needed for domestic and international indigenous Mexican migrants to address alcohol use behavior in the context of migration. 相似文献
160.
Hugo Salgado Isa Haviland Marcella Hernandez Diana Lozano Ruby Osoria David Keyes Eastern Kang María Luisa Zúñiga 《Journal of immigrant and minority health / Center for Minority Public Health》2014,16(3):340-347
Evidence suggests that in the US perceived discrimination among migrants of Mexican origin is associated with depressive symptoms. Factors that confer resilience, such as religiosity, could serve as a mediating factor in the context of migration stressors. We hypothesized that migration is associated with higher depressive symptoms and that discrimination and religiosity would mediate this relationship in a binational (US and Mexican) sample of indigenous Mexican migrants. We applied path analysis modeling to test our hypotheses with a sample of 650 individuals (n = 583 in Mexico; n = 67 in US). Results indicated that migration experience and current US residence were associated with perceived discrimination, which in turn were associated with a higher risk for depressive symptoms. Among women not living in the US, religiosity was associated with lower perceived discrimination. Discrimination is pervasive among male and female transnational and domestic migrants and religiosity may serve as a protective factor against discrimination for some women. 相似文献