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排序方式: 共有2459条查询结果,搜索用时 156 毫秒
111.
Cold groundwater temperatures and conductive heat flow in the Mt. Amiata geothermal area, Tuscany, Italy 总被引:1,自引:0,他引:1
Giovanni Chiodini Paola Comodi Stefano Giaquinto Bruno Mattioli Anna Rosa Zanzari 《Geothermics》1988,17(4)
The hydrogeochemical study of the cold springs present in the Mt. Amiata geothermal area, where the Bagnore and Piancastagnaio geothermal fields are situated, has defined the different shallow groundwater systems.The cold groundwater temperature of the volcanic phreatic aquifer is largely correlated with the geothermal heat flow. Through the analysis of the temperature of cold groundwaters, a possible method for geothermal prospection has been developed, supported by the results obtained in the studied area. Through the enthalpic balance of the aquifer and in agreement with available data, a geothermal flow of about 200 mW m-2 has been calculated. 相似文献
112.
Erica Costantini Lisa Aielli Federica Serra Lorenzo De Dominicis Katia Falasca Pamela Di Giovanni Marcella Reale 《International journal of molecular sciences》2022,23(4)
Wound healing (WH) proceeds through four distinct phases: hemostasis, inflammation, proliferation, and remodeling. Impaired WH may be the consequence of the alteration of one of these phases and represents a significant health and economic burden to millions of individuals. Thus, new therapeutic strategies are the topics of intense research worldwide. Although radiofrequency electromagnetic field (RF-EMF) has many medical applications in rehabilitation, pain associated with musculoskeletal disorders, and degenerative joint disorders, its impact on WH is not fully understood. The process of WH begins just after injury and continues during the inflammatory and proliferative phases. A thorough understanding of the mechanisms by which RF-EMF can improve WH is required before it can be used as a non-invasive, inexpensive, and easily self-applicable therapeutic strategy. Thus, the aim of this study is to explore the therapeutic potential of different exposure setups of RF-EMF to drive faster healing, evaluating the keratinocytes migration, cytokines, and matrix metalloproteinases (MMPs) expression. The results showed that RF-EMF treatment promotes keratinocytes’ migration and regulates the expression of genes involved in healing, such as MMPs, tissue inhibitors of metalloproteinases, and pro/anti-inflammatory cytokines, to improve WH. 相似文献
113.
114.
Pablo J. Giraudi Noel Salvoza Deborah Bonazza Carlo Saitta Daniele Lombardo Biagio Casagranda Nicol de Manzini Teresa Pollicino Giovanni Raimondo Claudio Tiribelli Silvia Palmisano Natalia Rosso 《International journal of molecular sciences》2022,23(5)
Fibrosis is the strongest predictor for disease-specific mortality in non-alcoholic fatty liver diseases (NAFLD), but the need for liver biopsy limits its diagnosis. We assessed the performance of plasma ficolin-2 (FCN-2) as a biomarker of fibrosis identified by an in silico discovery strategy. Two hundred and thirty-five morbidly obese (MO) subjects with biopsy-proven NAFLD stratified by fibrosis stage (F0, n = 44; F1, n = 134; F2, n = 46; F3/F4, n = 11) and 40 cirrhotic patients were enrolled. The cohort was subdivided into discovery (n = 76) and validation groups (n = 159). The plasma level of FCN-2 and other candidate markers was determined. FCN-2 was inversely correlated with the stage of liver fibrosis (ρ = −0.49, p < 0.001) independently of steatosis (p = 0.90), inflammation (p = 0.57), and ballooning (p = 0.59). In the global cohort, FCN-2 level decreased significantly in a stepwise fashion from F0/F1 (median 4753 ng/mL) to F2–F3–F4 (2760 ng/mL) and in cirrhotic subjects (1418 ng/mL). The diagnostic performance of FCN-2 in detecting F ≥ 2 was higher than other indexes (APRI, FIB-4) (AUROC 0.82, 0.68, and 0.6, respectively). The accuracy improved when combined with APRI score and HDL values (FCNscore, AUROC 0.85). Overall, the FCN-2 plasma level can accurately discriminate liver fibrosis status (minimal vs. moderate/advanced) significantly improving the fibrosis diagnostic algorithms. 相似文献
115.
Francesco Borgia Lucia Peterle Paolo Custurone Mario Vaccaro Giovanni Pioggia Sebastiano Gangemi 《International journal of molecular sciences》2022,23(6)
Acne Vulgaris (AV) and Hidradenitis suppurativa (HS) are common chronic inflammatory skin conditions that affect the follicular units that often coexist or are involved in differential diagnoses. Inflammation in both these diseases may result from shared pathways, which may partially explain their frequent coexistence. MicroRNAs (miRNAs) are a class of endogenous, short, non-protein coding, gene-silencing or promoting RNAs that may promote various inflammatory diseases. This narrative review investigates the current knowledge regarding miRNAs and their link to AV and HS. The aim is to examine the role of these molecules in the pathogenesis of AV and HS and to identify possible common miRNAs that could explain the similar characteristics of these two diseases. Five miRNA (miR-155 miR-223-, miR-21, and miRNA-146a) levels were found to be altered in both HS and AV. These miRNAs are related to pathogenetic aspects common to both pathologies, such as the regulation of the innate immune response, regulation of the Th1/Th17 axis, and fibrosis processes that induce scar formation. This review provides a starting point for further studies aimed at investigating the role of miRNAs in AV and HS for their possible use as diagnostic-therapeutic targets. 相似文献
116.
The purpose of the article is to provide some evidence on the interconnection between capital structure, R&D investment and ownership concentration using a unique panel data-set of Italian firms. We study the effect of R&D intensity on leverage for two groups of firms which are different in terms of their degree of ownership concentration. Our results suggest for Public Limited Companies, a nonlinear relationship between R&D intensity and leverage, with the latter first increasing and then decreasing. Interestingly, the same result is not found to hold true for Private Limited Companies, which are characterized by a more concentrated ownership. 相似文献
117.
Cu and Zn modified 13X zeolites prepared by ion exchange or impregnation and activated carbons (ACs) treated with KOH, NaOH or Na2CO3 solutions were studied as H2S sorbents for biogas purification for fuelling molten carbonate fuel cells. H2S sorption was studied in a new experimental set-up equipped with a high sensitivity potentiometric system for the analysis of H2S. Breakthrough curves were obtained at 40 °C with a fixed bed of 20 mg of the samples under a stream (6 L h−1) of 8 ppm H2S/He mixture. The adsorption properties of 13X zeolite improved with addition of Cu or Zn:Cu exchanged zeolite showed the best performances with a breakthrough time of 580 min at 0.5 ppm H2S, that is 12 times longer than the parent zeolite. In general, unmodified and modified ACs were more effective H2S sorbents than zeolites. Treating ACs with NaOH, KOH, or Na2CO3 solutions improved the H2S adsorption properties: AC treated with Na2CO3 was the most effective sorbent, showing a breakthrough time of 1222 min at 0.5 ppm, that is twice the time of the parent AC. 相似文献
118.
Daniele Penchini Giovanni Cinti Gabriele Discepoli Umberto Desideri 《International Journal of Hydrogen Energy》2014
High temperature steam electrolyzers, taking advantage of high temperature heat, can produce more hydrogen by using less electrical energy than low temperature electrolyzers. This paper presents an experimental study on hydrogen production by using a 200 W solid oxide stack working in reverse mode. A thermodynamic study of the process was performed by measuring the heat and mass balance of stack at different operating conditions. Different definitions of efficiency were used to highlight the limit and potential of the process. The I–V curve, the flow rate measurements and the GC analysis on outlet flows were used to calculate the hydrogen and oxygen productions. In addition, the influence of steam dilution, water utilization and operating temperature on conversion efficiency and stack's thermal balance was evaluated. With this aim, the tests were performed at three operating temperature (700 °C, 750 °C and 800 °C) over a range of steam inlet concentration from 50% to 90% and water utilization up to 70%. The hydrogen and oxygen flows produced by electrolysis, at different loads, were directly measured after water condensation: net flows up to 2.4 ml/(min cm2) of hydrogen and 1.2 ml/(min cm2) of oxygen were measured and compared to the theoretical ones, showing a good agreement. 相似文献
119.
The literature dedicated to the analysis of the difference in research productivity between the sexes tends to agree in indicating
better performance for men. Through bibliometric examination of the entire population of research personnel working in the
scientific-technological disciplines of Italian university system, this study confirms the presence of significant differences
in productivity between men and women. The differences are, however, smaller than reported in a large part of the literature,
confirming an ongoing tendency towards decline, and are also seen as more noticeable for quantitative performance indicators
than other indicators. The gap between the sexes shows significant sectorial differences. In spite of the generally better
performance of men, there are scientific sectors in which the performance of women does not prove to be inferior. 相似文献
120.
Food traceability is essential to preserve the identity of unique quality traits against frauds or commercial disputes. Therefore, there is a growing demand of new traceability systems for the collection of information related to units/batches of food ingredients and products. 相似文献