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排序方式: 共有622条查询结果,搜索用时 15 毫秒
51.
Marcello Candelli Laura Franza Giulia Pignataro Veronica Ojetti Marcello Covino Andrea Piccioni Antonio Gasbarrini Francesco Franceschi 《International journal of molecular sciences》2021,22(12)
Lipopolysaccharides (LPSs) are bacterial surface glycolipids, produced by Gram-negative bacteria. LPS is known to determine acute inflammatory reactions, particularly in the context of sepsis. However, LPS can also trigger chronic inflammation. In this case, the source of LPS is not an external infection, but rather an increase in endogenous production, which is usually sustained by gut microbiota (GM), and LPS contained in food. The first site in which LPS can exert its inflammatory action is the gut: both GM and gut-associated lymphoid tissue (GALT) are influenced by LPS and shift towards an inflammatory pattern. The changes in GM and GALT induced by LPS are quite similar to the ones seen in IBD: GM loses diversity, while GALT T regulatory (Tregs) lymphocytes are reduced in number, with an increase in Th17 and Th1 lymphocytes. Additionally, the innate immune system is triggered, through the activation of toll-like receptor (TLR)-4, while the epithelium is directly damaged, further triggering inflammation. In this review, we will discuss the importance of the crosstalk between LPS, GM, and GALT, and discuss the possible implications. 相似文献
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1923 Gleno Dam Break: Case Study and Numerical Modeling 总被引:2,自引:0,他引:2
Marco Pilotti Andrea Maranzoni Massimo Tomirotti Giulia Valerio 《Canadian Metallurgical Quarterly》2011,137(4):480-492
On the morning of December 1, 1923, the Gleno Dam (located in the Central Italian Alps) suddenly collapsed a few days after the first complete reservoir filling. Nearly 4.5×106??m3 of water was released. The consequent inundation caused significant destruction along the downstream valley and a death toll of at least 356 lives. This failure is the only historical case of dam break caused by structural deficiencies that has occurred in Italy. As a result, it has deeply influenced the evolution of Italian regulations regarding dam design and hydraulic risk evaluation. However, in spite of its relevance, this event has never been characterized from a hydraulic standpoint. This paper reports the main information obtained from the analysis of a vast amount of historical documents regarding the Gleno Dam break to set up a case study useful for validating dam-break models in mountain settings. Moreover, it presents the main results of one-dimensional (1D) modeling of the dam break wave propagation accomplished with a first-order finite volume numerical scheme recently proposed in the literature for field applications. The overall effectiveness and reliability of the model are evaluated for this case characterized by very irregular topography. Finally, the practical relevance of several choices that the numerical reconstruction of this kind of event demands is tested. 相似文献
54.
Dane Bicanic Vincenzo Fogliano Svjetlana Luterotti Jan Swarts Giovanni Piani Giulia Graziani 《Journal of the science of food and agriculture》2005,85(7):1149-1153
A new photothermal method suitable for direct, accurate and highly reproducible quantitative measurements of lycopene in tomato products has been introduced. The intrinsic precision of the method is typically better than 0.2%; the repeatability of determination is comparable to that of high‐performance liquid chromatography, with 0.86% least overall error. Copyright © 2005 Society of Chemical Industry 相似文献
55.
Cristina Mazzaccara Bruno Mirra Ferdinando Barretta Martina Caiazza Barbara Lombardo Olga Scudiero Nadia Tinto Giuseppe Limongelli Giulia Frisso 《International journal of molecular sciences》2021,22(11)
Mitochondrial Cardiomyopathy (MCM) is a common manifestation of multi-organ Mitochondrial Diseases (MDs), occasionally present in non-syndromic cases. Diagnosis of MCM is complex because of wide clinical and genetic heterogeneity and requires medical, laboratory, and neuroimaging investigations. Currently, the molecular screening for MCM is fundamental part of MDs management and allows achieving the definitive diagnosis. In this article, we review the current genetic knowledge associated with MDs, focusing on diagnosis of MCM and MDs showing cardiac involvement. We searched for publications on mitochondrial and nuclear genes involved in MCM, mainly focusing on genetic screening based on targeted gene panels for the molecular diagnosis of the MCM, by using Next Generation Sequencing. Here we report twelve case reports, four case-control studies, eleven retrospective studies, and two prospective studies, for a total of twenty-nine papers concerning the evaluation of cardiac manifestations in mitochondrial diseases. From the analysis of published causal mutations, we identified 130 genes to be associated with mitochondrial heart diseases. A large proportion of these genes (34.3%) encode for key proteins involved in the oxidative phosphorylation system (OXPHOS), either as directly OXPHOS subunits (22.8%), and as OXPHOS assembly factors (11.5%). Mutations in several mitochondrial tRNA genes have been also reported in multi-organ or isolated MCM (15.3%). This review highlights the main disease-genes, identified by extensive genetic analysis, which could be included as target genes in next generation panels for the molecular diagnosis of patients with clinical suspect of mitochondrial cardiomyopathies. 相似文献
56.
Stefano Sivolella Giulia Brunello Nadia Ferrarese Alessandro Della Puppa Domenico D’Avella Eriberto Bressan Barbara Zavan 《International journal of molecular sciences》2014,15(2):3088-3117
Injury to peripheral nerves can occur as a result of various surgical procedures, including oral and maxillofacial surgery. In the case of nerve transaction, the gold standard treatment is the end-to-end reconnection of the two nerve stumps. When it cannot be performed, the actual strategies consist of the positioning of a nerve graft between the two stumps. Guided nerve regeneration using nano-structured scaffolds is a promising strategy to promote axon regeneration. Biodegradable electrospun conduits composed of aligned nanofibers is a new class of devices used to improve neurite extension and axon outgrowth. Self assembled peptide nanofibrous scaffolds (SAPNSs) demonstrated promising results in animal models for central nervous system injuries, and, more recently, for peripheral nerve injury. Aims of this work are (1) to review electrospun and self-assembled nanofibrous scaffolds use in vitro and in vivo for peripheral nerve regeneration; and (2) its application in peripheral nerve injuries treatment. The review focused on nanofibrous scaffolds with a diameter of less than approximately 250 nm. The conjugation in a nano scale of a natural bioactive factor with a resorbable synthetic or natural material may represent the best compromise providing both biological and mechanical cues for guided nerve regeneration. Injured peripheral nerves, such as trigeminal and facial, may benefit from these treatments. 相似文献
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Alberto Regattieri Giulia Santarelli Mauro Gamberi Rita Gamberini 《Packaging Technology and Science》2014,27(8):591-608
This paper focuses on the analysis of the internal flow traceability of goods (products and/or packages) along the supply chain by Radio Frequency IDentification (RFID) technology. Traditionally, the traceability system is performed through the asynchronous fulfilment of checkpoints (i.e. doorways) by materials. In such cases, the tracking is manual, executed by operators that manually trace the path. Often, companies are not aware of the inefficiencies because of these traceability systems such as low precision and accuracy in measurements (i.e. no information between doorways), more time spent by operators and costs (due to the full effort of operators who have to search for the good positions and movements). In order to overcome these limitations, automatic identification procedures have been introduced in many service industries, purchasing and distribution logistics, manufacturing companies and material flow systems. Automatic identification procedures can also be applied to the packaging of products, instead of to each item contained in the package. Sometimes, products are very expensive, and packages contain important and critical goods (e.g. dangerous or explosive materials); thus, the tracking of goods – and packages in particular – is a critical function. In order to analyse the traceability of the packaging system, the authors have developed an innovative system based on Radio Frequency IDentification‐Ultra Wide Band (RFID‐UWB) technology. A prototype of this system has been realized and used for an experimental research that has consisted of several tests (static and dynamic), tracing the position (static) and movements (dynamic) of products and in particular packages in indoor environments, in continuous and in real time. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
59.
The Role of Higher Lying Electronic States in Charge Photogeneration in Organic Solar Cells
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Giulia Grancini Maddalena Binda Stefanie Neutzner Luigino Criante Vittorio Sala Alberto Tagliaferri Guglielmo Lanzani 《Advanced functional materials》2015,25(44):6893-6899
The role of excess photon energy on charge generation efficiency in bulk heterojunction solar cells is still an open issue for the organic photovoltaic community. Here, the spectral dependence of the internal quantum efficiency (IQE) for a poly[2,6‐(4,4‐bis‐(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b]dithiophene)‐alt‐4,7‐(2,1,3‐benzothiadiazole)]:6,6‐phenyl‐C61‐butyric acid methyl ester (PCPDTBT:PC60BM)‐based solar cell is derived combining accurate optoelectronic characterization and comprehensive optical modeling. This joint approach is shown to be essential to get reliable values of the IQE. Photons with energy higher than the bandgap of the donor material can effectively contribute to enhance the IQE of the solar cell. This holds true independently of the device architecture, reflecting an intrinsic property of the active material. Moreover, the nanomorphology of the bulk heterojunction plays a crucial role in determining the IQE spectral dependence: the coarser and more crystalline, the lesser the gain in IQE upon high energy excitation. 相似文献
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