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41.
Commiphora myrrha (Nees) Engl. extracts: evaluation of antioxidant and antiproliferative activity and their ability to reduce microbial growth on fresh‐cut salad 下载免费PDF全文
Luisa Boffa Arianna Binello Valentina Boscaro Margherita Gallicchio Gabriella Amisano Stefania Fornasero Giancarlo Cravotto 《International Journal of Food Science & Technology》2016,51(3):625-632
With the aim to develop natural preservatives displaying also chemopreventive activity, different Commiphora myrrha (Nees) Engl. extracts were studied. Myrrh essential oils, obtained by steam distillation and microwave‐assisted hydrodistillation, and several other extracts, obtained by sequential procedures with petroleum ether (PE), ethanol, ethyl acetate and butanol, have been screened for their antioxidant (DPPH· scavenging assay) and antiproliferative activity (on both nontumour and colon cancer cell lines) without previous purification. Considering that the colon cancer cell lines were more sensitive to PE and ethanol extracts, the latter of which showed the highest antioxidant activity (EC50 = 0.160 ± 0.008 mg mL?1), both have been selected for further antibacterial/antifungal activity tests using an antimicrobial diffusion test and a growth inhibition test on salads. Results showed that the ethanol extract possessed the higher antibacterial and antifungal activity. Compared to untreated product, fresh‐cut salads treated with these two myrrh extracts displayed a significant lower bacterial growth. Although further investigation is required, these promising results offer hints as how to improve the shelf life of fresh‐cut salad. 相似文献
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Massimiliano Lanzi Francesco Paolo Di-Nicola Massimiliano Livi Luisa Paganin Fabio Cappelli Filippo Pierini 《Journal of Materials Science》2013,48(11):3877-3893
This article describes the preparation of thin films of conjugated polymers which can enhance their specific electrical conductivity by several orders of magnitude by changing their state from insulating to conducting materials. The examined polymers, i.e., a polyacetylenic and a polythiophenic derivative, are functionalized with thioalkylic side chains and are soluble in common organic solvents from which they lead to thick homogeneous films. The films can be deposited on different substrates, either rigid or flexible, and can be easily exposed to laser radiation to make them conductive. The process is irreversible, and the final conductivity is stable over time, even in the presence of high temperatures (up to 180 °C), moisture, and air. The high stability of treated samples, easy polymer synthesis and quick and inexpensive suitably tailored laser tracing procedure make these materials very promising for applications in organic electronics and in the development of new electronic circuitry. 相似文献
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Luisa Sánchez Brea Noelia Barreira Rodríguez Antonio Mosquera González Hugo Pena-Verdeal Eva Yebra-Pimentel Vilar 《Pattern Analysis & Applications》2018,21(2):563-577
Hyperaemia is an excess of blood in a tissue that causes the appearance of an unusual red hue in the affected area. It is a common occurrence in the bulbar conjunctiva, where it can be related to multiple pathologies, such as conjunctivitis or dry eye syndrome. Specialists grade hyperaemia by means of a tedious, subjective, non-repeatable and time-consuming process. These drawbacks can be solved with the automatisation of the process by means of image processing techniques. The automatic segmentation of the conjunctiva is an important part of the process, as it ensures the absence of noise in posterior stages of the methodology. However, there are several issues of illumination and focus in the input videos that difficult the process. In this work, several segmentation algorithms are proposed and compared in order to obtain an accurate location of the bulbar conjunctiva. 相似文献
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D. Caccavo P. Apicella G. Lamberti A. A. Barba 《Chemical Engineering Communications》2017,204(12):1333-1340
One of the main aims in agriculture is to guarantee soil wellness, which is a fundamental requirement to produce high-quality crops with high yields. Focused on this aim, periodical administrations of nutrients or phytostrengtheners are often necessary. The most relevant disadvantages of these administrations are the high dosage number required and the low availability of the substance within the soil. For these reasons, a crucial goal to increase the economic and environmental sustainability of the cultivation process is to reduce the dosage number, which can be obtained increasing the active substance availability in the soil. A granular hydroxypropyl methylcellulose (HPMC) matrix, produced using the wet granulation process, was used to encapsulate a phytostrengthener and to guarantee its controlled release. The granular product was characterized in terms of granules properties and phytostrengtheners leaching within the soil. The results showed good flowability and mechanical properties of the granules as well as the possibility to reduce the product leaching with the phytostrengtheners encapsulation in the HPMC matrices. 相似文献
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Alberto Abad Anna Pompili Angela Costa Isabel Trancoso José Fonseca Gabriela Leal Luisa Farrajota Isabel P. Martins 《Computer Speech and Language》2013,27(6):1235-1248
One of the most common effects among aphasia patients is the difficulty to recall names or words. Typically, word retrieval problems can be treated through word naming therapeutic exercises. In fact, the frequency and the intensity of speech therapy are key factors in the recovery of lost communication functionalities. In this sense, speech and language technology can have a relevant contribution in the development of automatic therapy methods. In this work, we present an on-line system designed to behave as a virtual therapist incorporating automatic speech recognition technology that permits aphasia patients to perform word naming training exercises. We focus on the study of the automatic word naming detector module and on its utility for both global evaluation and treatment. For that purpose, a database consisting of word naming therapy sessions of aphasic Portuguese native speakers has been collected. In spite of the different patient characteristics and speech quality conditions of the collected data, encouraging results have been obtained thanks to a calibration method that makes use of the patients’ word naming ability to automatically adapt to the patients’ speech particularities. 相似文献
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