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101.
Laryngotracheal stenosis (LTS) is a complex and heterogeneous disease whose pathogenesis remains unclear. LTS is considered to be the result of aberrant wound-healing process that leads to fibrotic scarring, originating from different aetiology. Although iatrogenic aetiology is the main cause of subglottic or tracheal stenosis, also autoimmune and infectious diseases may be involved in causing LTS. Furthermore, fibrotic obstruction in the anatomic region under the glottis can also be diagnosed without apparent aetiology after a comprehensive workup; in this case, the pathological process is called idiopathic subglottic stenosis (iSGS). So far, the laryngotracheal scar resulting from airway injury due to different diseases was considered as inert tissue requiring surgical removal to restore airway patency. However, this assumption has recently been revised by regarding the tracheal scarring process as a fibroinflammatory event due to immunological alteration, similar to other fibrotic diseases. Recent acquisitions suggest that different factors, such as growth factors, cytokines, altered fibroblast function and genetic susceptibility, can all interact in a complex way leading to aberrant and fibrotic wound healing after an insult that acts as a trigger. However, also physiological derangement due to LTS could play a role in promoting dysregulated response to laryngo-tracheal mucosal injury, through biomechanical stress and mechanotransduction activation. The aim of this narrative review is to present the state-of-the-art knowledge regarding molecular mechanisms, as well as mechanical and physio-pathological features behind LTS.  相似文献   
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103.
The problem of see-through cancelation in digital images of double-sided documents is addressed. We show that a nonlinear convolutional data model proposed elsewhere for moderate show-through can also be effective on strong back-to-front interferences, provided that the recto and verso pure patterns are estimated jointly. To this end, we propose a restoration algorithm that does not need any classification of the pixels. The see-through PSFs are estimated off-line, and an iterative procedure is then employed for a joint estimation of the pure patterns. This simple and fast algorithm can be used on both grayscale and color images and has proved to be very effective in real-world cases. The experimental results we report in this paper demonstrate that our algorithm outperforms the ones based on linear models with no need to tune free parameters and remains computationally inexpensive despite the nonlinear model and the iterative solution adopted. Strategies to overcome some of the residual difficulties are also envisaged.  相似文献   
104.
项目地点:沙特阿拉伯利雅得项目类型:建筑(住宅)开工日期:未知该项目获2005年豪瑞可持续建筑大奖赛非洲中东地区提名奖  相似文献   
105.
There are many abandoned underground mines beneath the city of Rome, created in the Pleistocene pyroclastic deposits over thousands of years. These pose a serious public safety risk hence the study was undertaken to better assess the stability of the underground workings. The Villa de Sanctis public park was selected as a suitable test site, as in this area the cavity network can be inspected and the different steps of the progressive migration of voids toward the surface can be identified. In addition to an underground geological survey, geophysical investigations were undertaken to elucidate some key characteristics of the involved lithological units, including elastic stiffness and layer thickness. Recommendations are made for further studies of the accessible and inaccessible areas.  相似文献   
106.
In many cases masonry buildings present structural problems related to development of local mechanisms under seismic actions. The solution to this weakness has to be chosen taking into account several aspects if the construction is ancient and is gifted of monumental significance. In this paper the case of the Bell Tower of Santa Maria del Carmine (Napoli, Italy) is discussed; the construction has been deeply examined by the writers performing experimental inquires in situ and theoretical analysis with three-dimensional models. While the results obtained in the hypothesis of compact behavior of the structure have pointed out a low risk condition under seismic actions, in contrast the study of local out-of-plane mechanisms, dealt with in detail in this paper, have evidenced an unsafe situation. To avoid such mechanisms, connective systems with tie rods made of glass fiber-reinforced polymer laminates have been designed to be inserted where local verifications are not satisfied. Design, application, and monitoring procedures of this innovative intervention are discussed in detail herein.  相似文献   
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108.
Thirty commercially available Italian carbonic macerated young red wines, have been analysed by HPLC–DAD–MS with the aim to characterise their pigment composition and find possible correlations with the colour features evaluated by means of spectrophotometric measurements. The composition in anthocyanin monoglucosides, acetates, p-coumarates as well as that in pyranoanthocyanins and direct and ethyl-bridged adducts with flavanols, was studied. Because of the peculiar maceration process, carbonic macerated wines demonstrated to be qualitatively rich in pyranoanthocyanins and pigment adducts. A number of ethyl-bridged anthocyanin isomers was found, together with significant contents of vitisin A and vitisin B (up to 15.5 mg/L as a sum). Malvidin-3-glc-4-vinylphenol was the main pyranoanthocyanin-vinylphenol adduct (up to 1.10 mg/L). The colour features of the wines were broadly distributed as a consequence of the percentage of carbonic macerated wine present in the marketed product. The statistical treatment of the entire data set revealed that pyranoanthocyanins are positively correlated with colour density (while no correlation was found for monoglucosides) and that direct adducts and/or ethyl-bridged compounds can play a role for what concerns the hue of carbonic macerated wines.  相似文献   
109.
Different yeast nutrient additions were studied for the 2008 and 2009 vintages of Verdicchio grape juice fermentation. Addition of yeast derivatives at the beginning of fermentation and/or different amounts of diammonium phosphate at various times within the first half of fermentation were examined, with initial yeast assimilable nitrogen concentrations set at 200 and 250 mg l?1. Supplementation with glutathione in combination with this nitrogen addition was also evaluated. Fermentation rates were monitored throughout these fermentations carried out under different nutrient conditions. H2S production during fermentation and synthesis of volatile compounds in the finished wines were quantified; the wines also underwent sensory evaluation. The fermentation kinetics were almost exclusively influenced by the inorganic nitrogen supplementation with diammonium phosphate. H2S evolution was more affected by assimilable nitrogen than glutathione. Diammonium phosphate significantly reduced H2S production, with a further reduction in the presence of yeast derivative. This nitrogen supplementation yielded higher concentrations of acetate esters, and in particular of isoamyl acetate (fruity aromas), which positively influences the analytical and aroma profile of wines and results in a general reduction in 2-phenylethanol production (floral aromas). Overall results (two harvesting times and vintages) indicate that the management with diammonium phosphate and yeast derivative supplementation improves the kinetics of fermentation and provides a good tool to reduce H2S formation and increase the analytical and sensory quality of Verdicchio wine.  相似文献   
110.
The precipitation temperatures of sodium caseinate in H2O and D2O in the presence of Mg2+, Ca2+, Sr2+ and Ba2+ were investigated through fluorescence, turbidity and conductivity experiments.  相似文献   
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