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81.
Berardinelli A Cevoli C Silaghi FA Fabbri A Ragni L Giunchi A Bassi D 《Journal of food science》2010,75(7):E462-E468
Abstract: The nondestructive assessment of apricot fruit quality (Bora cultivar) was carried out by means of FT-NIR reflectance spectroscopy in the wavenumber range 12000 to 4000 cm−1. Samples were harvested at four different ripening stages and scanned by a fiber optical probe immediately after harvesting and after a storage of 3 d (2 d at 4 °C and 1 d at 18 °C); the flesh firmness (FF), the soluble solids content (SSC), the acidity (A), and the titratable acidity (malic and citric acids) were then measured by destructive methods. Soft independent modeling of class analogy (SIMCA) analysis was used to classify spectra according to the ripening stage and the storage: partial least squares regression (PLS) models to predict FF, SSC, A, and the titratable acidity were also set-up for both just harvested and stored apricots. Spectral pretreatments and wavenumber selections were conducted on the basis of explorative principal component analysis (PCA). Apricot spectra were correctly classified in the right class with a mean classification rate of 87% (range: 80% to 100%). Test set validations of PLS models showed R2 values up to 0.620, 0.863, 0.842, and 0.369 for FF, SSC, A, and the titratable acidity, respectively. The best models were obtained for the SSC and A and are suitable for rough screening; a lower power prediction emerged for the other maturity indices and the relative predictive models are not recommended. Practical Application : The results of the study could be used as a tool for the assessment of the ripening stage during the harvest and the quality during the postharvest storage of apricot fruits. 相似文献
82.
Giacomo Luigi Petretto Carlo Ignazio Giovanni Tuberoso Maurizio Antonio Fenu Jonathan P. Rourke Omar Belhaj Giorgio Pintore 《International Journal of Food Properties》2017,20(9):2016-2027
The bioprospecting of several monofloral Moroccan honeys was carried out. The antiradical activity expressed as mmol Trolox equivalents/kg of honey and evaluated by 2,2-diphenyl-1-picrylhydrazyl assay, ranged from 0.15 for euphorb honey to 1.08 for citrus honey. The antioxidant activity expressed as mmol Fe2+/kg and evaluated by ferric ion reducing antioxidant power assay, ranged from 0.96 for euphorb honey to 4.74 for orange honey. The total phenol content was evaluated by colorimetric assay, while the color attributes were evaluated as transmittance data. Significant Pearson correlation factors were found between total polyphenol amount and antioxidant activity and between color attributes and antioxidant activity. Furthermore the chemical composition of volatile organic compounds was determined. The volatile organic compounds chemical composition of the studied honeys was mainly represented by terpene and benzene derivatives, Maillard reaction products, isoprenoids, and hydrocarbons. The volatiles fingerprint, as well as a targeted high-performance liquid chromatography analysis of the polar components, was used to tentatively confirm the declared botanical origin of the samples studied. 相似文献
83.
84.
Martina Casarin Tiago Moderno Fortunato Saima Imran Martina Todesco Deborah Sandrin Giulia Borile Ilaria Toniolo Massimo Marchesan Gino Gerosa Andrea Bagno Filippo Romanato Emanuele Luigi Carniel Alessandro Morlacco Fabrizio Dal Moro 《International journal of molecular sciences》2022,23(5)
Bladder cancer (BC) is among the most common malignancies in the world and a relevant cause of cancer mortality. BC is one of the most frequent causes for bladder removal through radical cystectomy, the gold-standard treatment for localized muscle-invasive and some cases of high-risk, non-muscle-invasive bladder cancer. In order to restore urinary functionality, an autologous intestinal segment has to be used to create a urinary diversion. However, several complications are associated with bowel-tract removal, affecting patients’ quality of life. The present study project aims to develop a bio-engineered material to simplify this surgical procedure, avoiding related surgical complications and improving patients’ quality of life. The main novelty of such a therapeutic approach is the decellularization of a porcine small intestinal submucosa (SIS) conduit to replace the autologous intestinal segment currently used as urinary diversion after radical cystectomy, while avoiding an immune rejection. Here, we performed a preliminary evaluation of this acellular product by developing a novel decellularization process based on an environmentally friendly, mild detergent, i.e., Tergitol, to replace the recently declared toxic Triton X-100. Treatment efficacy was evaluated through histology, DNA, hydroxyproline and elastin quantification, mechanical and insufflation tests, two-photon microscopy, FTIR analysis, and cytocompatibility tests. The optimized decellularization protocol is effective in removing cells, including DNA content, from the porcine SIS, while preserving the integrity of the extracellular matrix despite an increase in stiffness. An effective sterilization protocol was found, and cytocompatibility of treated SIS was demonstrated from day 1 to day 7, during which human fibroblasts were able to increase in number and strongly organize along tissue fibres. Taken together, this in vitro study suggests that SIS is a suitable candidate for use in urinary diversions in place of autologous intestinal segments, considering the optimal results of decellularization and cell proliferation. Further efforts should be undertaken in order to improve SIS conduit patency and impermeability to realize a future viable substitute. 相似文献
85.
Luigi Catuogno Roberto Gassirà Michele Masullo Ivan Visconti 《Information Security Technical Report》2013,17(3):93-104
A smart card is a tamper-resistant miniature computer that performs some basic computations on input a secret information. So far, smart cards have been widely used for securing many digital transactions (e.g., pay television, ATM machines).We focus on the implementation of operating system security services leveraging on smart cards. This very challenging feature allows one to personalize some functionalities of the operating system by simply changing a smart card. Current solutions for integrating smart card features in operating system services require at least a partial execution of some of the operating system functionalities at “user level”. Unfortunately, system functionalities built on top of components lying at both kernel and user levels may negatively affect the overall system security, due to the introduction of multiple points of failure.In this work, we present the design and implementation of SmartK: a framework that integrates features of smart cards uniquely in the Linux kernel. In order to validate our approach, we propose a host of enhancements to the Linux operating system built on top of SmartK: 1) in-kernel clients' authentication with Kerberos; 2) execution of trusted code; 3) key management in secure network filesystems.In particular, we present an experimental Linux OS distribution (SalSA), which addresses the security issues related to downloading packages and to updating an operating system through the Internet. 相似文献
86.
The evaluation of the work of a researcher and its impact on the research community has been deeply studied in literature through the definition of several measures, first among all the h-index and its variations. Although these measures represent valuable tools for analyzing researchers?? outputs, they usually assume the co-authorship to be a proportional collaboration between the parts, missing out their relationships and the relative scientific influences. In this work, we propose the d-index, a novel measure that estimates the dependence degree between authors on their research environment along their entire scientific publication history. We also present a web application that implements these ideas and provides a number of visualization tools for analyzing and comparing scientific dependences among all the scientists in the DBLP bibliographic database. Finally, relying on this web environment, we present case and user studies that highlight both the validity and the reliability of the proposed evaluation measure. 相似文献
87.
Gianluca Paravati Andrea Sanna Fabrizio Lamberti Luigi Ciminiera 《Mobile Networks and Applications》2011,16(3):385-393
Wireless communication advances have enabled emerging video streaming applications to mobile handheld devices. For example,
it is possible to display and interact with complex 3D virtual environments on mobile devices that don’t have enough computational
and storage capabilities (e.g. smart phones, PDAs) through remote rendering techniques, where a server renders 3D data and
streams the corresponding image flow to the client. However, due to fluctuations in bandwidth characteristics and limited
mobile device CPU capabilities, it is extremely challenging to design effective systems for streaming interactive multimedia
over wireless networks. This paper presents a novel approach based on a controller that can automatically adjust streaming
parameters basing on feedback measures from the client device. Experimental results prove the effectiveness of the proposed
solution in coping with bandwidth changes, thus providing high Quality of Service (QoS) in remote visualizations. 相似文献
88.
Luigi Catuogno Hans Löhr Mark Manulis Ahmad-Reza Sadeghi Christian Stüble Marcel Winandy 《Datenschutz und Datensicherheit - DuD》2010,34(5):289-294
Trusted Virtual Domains (TVDs) provide a secure IT infrastructure offering a homogeneous and transparent enforcement of access
control policies on data and network resources. In this article, we give an overview of the fundamental ideas and basic concepts
behind TVDs, present a realization of TVDs, and discuss application scenarios. 相似文献
89.
Desmin and troponin T are degraded faster in type IIb muscle fibers than in type I fibers during postmortem aging of porcine muscle 总被引:1,自引:0,他引:1
A novel approach was applied in this study to directly evaluate the effect of muscle fiber type on postmortem protein degradation. Porcine muscle fibers were isolated from longissimus muscle at day 1, 3, and 6 postmortem. Fibers were sorted by immunochemical myosin heavy chain isoform typing. Western blot analysis of fibers pooled separately into type I or IIb showed that the relative amounts of 39- and 50-kDa desmin degradation fragments at day 6, and 28- to 31-kDa fragments of troponin T fast type isoform (fTnT) at day 1 and 6 postmortem were higher in type IIb than in type I fibers. At day 6 troponin T slow type isoform (sTnT) was less degraded than fTnT in type I fibers. These results indicated greater rate and extent of proteolysis in type IIb than in type I fibers and higher susceptibility of fTnT to proteolysis than that of sTnT isoform. 相似文献
90.
Francesco Venditti Francesca Cuomo Andrea Ceglie Luigi Ambrosone Francesco Lopez 《Journal of hazardous materials》2010,173(1-3):552-557
The feasibility of utilizing CTAB–silica gelatin composite (C-SGC) to remove hexavalent chromium from aqueous solutions under different conditions was investigated. Removal of chromate was assessed through evaluation of the adsorption kinetics of chromate ions on the composite under equilibrium conditions in the presence of sulfate ions and at a slightly acidic pH condition (pH 5.8). Adsorption competition tests in the presence of sulfate ions showed that Cr(VI) was still effectively adsorbed from aqueous solution regardless of the presence of the competing anions. In fact, the adsorption kinetics performed at different initial chromate concentrations were unaffected by the presence of 100 mg L?1 sulfate ions (pH 7.5). The equilibrium adsorption data were fitted by Freundlich adsorption isotherms which confirmed that the adsorption efficiency of chromium on the CTAB–silica gelatin composite was unchanged in the presence of sulfate ions. Further, the adsorption process was shown to be pH dependent and more efficient at slightly acidic pH (5.8). These findings demonstrated a high specificity of the CTAB–silica gelatin composite for chromium, and highlight the possibility of using this matrix for efficient removal of chromium from industrial wastewater without the need to eliminate contaminant sulfate ions. 相似文献