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排序方式: 共有1328条查询结果,搜索用时 31 毫秒
31.
Ashmitha P. Munasur Thirumala Govender Irene Mackraj 《Drug development and industrial pharmacy》2013,39(7):709-716
ABSTRACTThis study sought to identify and quantify the effects of environmental test parameters on the mucoadhesivity of a propranolol tablet. Their effects on Maximum Detachment Force (MDF) measurements were evaluated using a Box-Behnken design matrix. Prehydration time (PT) had a statistically significant negative main effect while contact force (CF) had no significant effect on in vitro MDF measurements. While contact time (CT) had no significant main or quadratic effects, it had a positive interaction effect with PT. The mathematical model was statistically validated and a PT of 3.5 min and a CT of 5 min was proposed for mucoadhesion testing by the tensile method during formulation optimization. 相似文献
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Gabriella Di Lena Irene Casini Roberto Caproni Elena Orban 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(3):175-182
This study investigated mercury contamination levels in eight commercially valuable crustacean species caught off the Central Adriatic and Tyrrhenian coasts of Italy. Total mercury levels were measured by Thermal Decomposition-Amalgamation-Atomic Absorption Spectrophotometry. Results showed a high variability among species with values ranging from 0.070 to 1.24 (mg kg?1 wet weight). The lowest mercury levels were detected in caramote prawn (Penaeus kerathurus), warty crab (Eriphia verrucosa) and European spider crab (Maja squinado), decapods living in shallow waters. Levels exceeding the limits established by the European Commission were found in species living in close contact with bottom sediments: deepwater rose shrimp (Parapenaeus longirostris), blue and red shrimp (Aristeus antennatus) and Norway lobster (Nephrops norvegicus). For shrimps, the inter-individual variability observed was mostly related to the body size, indicating the accumulation of mercury with age. An estimation of the human intake of mercury associated to the consumption of the crustaceans sampled and its comparison with the Tolerable Weekly Intake are provided. 相似文献
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Performance of different advanced oxidation processes for tertiary wastewater treatment to remove the pesticide acetamiprid 下载免费PDF全文
35.
Goyanes Manuel Demeter Márton Grané Aurea Albarrán-Lozano Irene Gil de Zúñiga Homero 《Scientometrics》2020,125(3):2299-2322
Scientometrics - With today’s research production and global dissemination, there is growing pressure to assess how academic fields foster diversity. Based on a mathematical problem/solve... 相似文献
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Iria da Cunha Eric San Juan Juan Manuel Torres-Moreno Marina Lloberese Irene Castellóne 《Expert systems with applications》2012,39(2):1671-1678
Nowadays discourse parsing is a very prominent research topic. However, there is not a discourse parser for Spanish texts. The first stage in order to develop this tool is discourse segmentation. In this work, we present DiSeg, the first discourse segmenter for Spanish, which uses the framework of Rhetorical Structure Theory and is based on lexical and syntactic rules. We describe the system and we evaluate its performance against a gold standard corpus, divided in a medical and a terminological subcorpus. We obtain promising results, which means that discourse segmentation is possible using shallow parsing. 相似文献
38.
Irene Pagana Ruben Morawicki Tiffany J. Hager 《International Journal of Food Science & Technology》2014,49(2):641-649
Organic waste generated from industrial sweet potato canning is estimated to be 30% of incoming raw material with significant residual carbohydrate content. The purpose of this study was to evaluate the potential of waste generated from sweet potato processing material to support the growth of lactic acid bacteria and the production of lactic acid. The waste was comprised of 16.5% solids consisting of 18.5% ash, 4.4% protein, 20.5% simple sugars and 19% soluble starch. Following a screening of three lactic acid bacteria strains, Lactobacillus rhamnosus was deemed the best candidate for lactic acid production. The potential of various dilutions of the enzyme‐hydrolysed waste, with and without pH control, as a fermentation substrate was evaluated. Lactic acid production was highest in hydrolysed waste (without dilution) at pH set point 5.0, yielding 10 g L?1 in 72 h. Thus, lactic acid, a valuable organic compound, can be generated from sweet potato waste. 相似文献
39.
Aldo Attanasio Elisabetta Ceretti Irene Fassi Claudia Pagano 《The International Journal of Advanced Manufacturing Technology》2017,92(5-8):1721-1729
In recent years, innovative materials such as carbon nanotube composites are finding growing interest in several industrial sectors, from sports and leisure to electronics, automotive, aircraft, and defence. The reinforcing influence of the carbon nanotube is of prime interest. However, technological issues concerning the production methods and the manufacturing processes of carbon nanotube components limit the industrial application of this innovative and interesting material, especially whether small features are required. For this reason, manufacturing strategy involving new production technologies must be designed and developed. This paper studies the challenges of a manufacturing chain based on two manufacturing processes: injection moulding and micro milling. A case study based on these innovative processes is reported and discussed. The propagation chain effect and the influence of each considered process parameter on cutting force and geometrical accuracy of the features (the key characteristics of the process chain) were assessed by means of statistical analysis of variance (ANOVA). The ANOVA analysis demonstrated that cutting forces in micro milling are mainly influenced by the material and percentage of carbon nanotubes, while the main parameter influencing the geometrical accuracy of micro features is the matrix material. 相似文献
40.
Irene Appolloni Sebastiano Curreli Sara Caviglia Manuela Barilari Eleonora Gambini Aldo Pagano Paolo Malatesta 《International journal of molecular sciences》2012,13(11):14667-14678
Tumor progression is a key aspect in oncology. Not even the overexpression of a powerful oncogenic stimulus such as platelet derived growth factor-B (PDGF-B) is sufficient per se to confer full malignancy to cells. In previous studies we showed that neural progenitors overexpressing PDGF-B need to undergo progression to acquire the capability to give rise to secondary tumor following transplant. By comparing the expression profile of PDGF-expressing cells before and after progression, we found that progressed tumors consistently downregulate the expression of the antiproliferative gene Btg2. We therefore tested whether the downregulation of Btg2 is sufficient and necessary for glioma progression with loss and gain of function experiments. Our results show that downregulation of Btg2 is not sufficient but is necessary for tumor progression since the re-introduction of Btg2 in fully progressed tumors dramatically impairs their gliomagenic potential. These results suggest an important role of Btg2 in glioma progression. Accordingly with this view, the analysis of public datasets of human gliomas showed that reduced level of Btg2 expression correlates with a significantly worse prognosis. 相似文献