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排序方式： 共有2134条查询结果，搜索用时 15 毫秒
951.
Piero Sestili Elena Barbieri Chiara Martinelli Michela Battistelli Michele Guescini Luciana Vallorani Lucia Casadei Alessandra D'Emilio Elisabetta Falcieri Giovanni Piccoli Deborah Agostini Giosuè Annibalini Marco Paolillo Anna Maria Gioacchini Vilberto Stocchi 《Molecular nutrition & food research》2009,53(9):1187-1204
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Foods with different moisture and fat contents (i.e. meat sauce and biscuits) were subjected to treatments at 4, 12 and 19 kPa for increasing lengths of time to remove furan and 5-hydroxymethylfurfural (HMF). The vacuum treatments were ineffective in removing HMF from both food types, as well as furan from the biscuits, unless this food was preliminary hydrated at high water activity. However, the vacuum treatments allowed furan to be removed from the high moisture food. In particular, 67% furan removal from the meat sauce was achieved by applying 12 kPa for 10 min. Sensory analysis results showed that meat sauce subjected to such a treatment presented the same odor intensity of the untreated sample. The post-process vacuum treatment could represent a reliable strategy to mitigate the furan levels in high moisture foods. 相似文献
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Damiana Pieragostino Michele D'Alessandro Maria di Ioia Carmine Di Ilio Paolo Sacchetta Piero Del Boccio 《Proteomics. Clinical applications》2015,9(1-2):169-186
Proteomics and metabolomics investigations of body fluids present several challenges for biomarker discovery of several diseases. The search for biomarkers is actually conducted in different body fluids, even if the ideal biomarker can be found in an easily accessible biological fluid, because, if validated, the biomarker could be sought in the healthy population. In this regard, tears could be considered an optimum material obtained by noninvasive procedures. In the past years, the scientific community has become more interested in the study of tears for the research of new biomarkers not only for ocular diseases. In this review, we provide a discussion on the current state of biomarkers research in tears and their relevance for clinical practice, and report the main results of clinical proteomics studies on systemic and eye diseases. We summarize the main methods for tear samples analyses and report recent advances in “omics” platforms for tears investigations. Moreover, we want to take stock of the emerging field of metabolomics and lipidomics as a new and integrated approach to study protein-metabolites interplay for biomarkers research, where tears represent a still unexplored and attractive field. 相似文献
956.
This study relies on the core ideas of the health belief model and suggests that short informational videos on Internet ‘addiction’ can be an effective means towards preventing problematic use of the Internet through their ability to drive changes in viewers’ attitudes towards reducing their Internet use. Building on the heuristic-systematic model of information processing viewpoint, it is further suggested that this attitude change is guided by the information the videos provide, as well as the surprise emotion they generate. To test this model, data were collected at three points in time from 223 participants who were exposed to one of two video interventions. Partial least-square analyses indicated that the videos were efficacious in improving viewers’ attitudes towards reducing their Internet use, after accounting for viewers’ preexisting attitudes, levels of Internet ‘addiction’, demographics and social desirability bias. Consistent with the heuristic-systematic model of information-processing perspective this effect was mobilised simultaneously through the information and surprise induced by the videos. 相似文献
957.
Cinzia Panigada Micol Rossini Lorenzo Busetto Michele Meroni Francesco Fava Roberto Colombo 《International journal of remote sensing》2013,34(12):3307-3332
Airborne hyperspectral remote observations, characterized by high spatial and spectral resolution, allow the estimation of quantitative vegetation variables useful in forest condition assessment. In this research, total chlorophyll (a?+ b) concentration (C ab), a biochemical variable describing crown discoloration rate, was mapped to assess oak (Quercus robur L.) condition in the Ticino Regional Park. A simulation experiment was conducted to evaluate the error in C ab estimation due to ecological variables (i.e. canopy leaf area index and understorey characteristics) and to sun-sensor configurations when optical indices are used. Canopy reflectance was simulated by means of the PROSPECT leaf radiative transfer model (Jacquemoud and Baret 1990) coupled with the SAILH canopy radiative transfer model, a variation of the SAIL (Scattering by Arbitrarily Inclined Leaves) model modified to include the hot spot effect (Verhoef 1984, Kuusk 1991). The vegetation was modelled as a two layer medium with oak canopy as the top layer and the understorey as the bottom layer. Simulations were performed for varying leaf C ab and canopy Leaf Area Index (LAI) of the top layer, θl (mean leaf inclination angle) and LAI of the bottom layer (LAIu) and sun-sensor geometry. Optical indices were calculated and used in C ab retrieval. Simulations demonstrated that errors in C ab estimation were negligible when MTCI (MERIS Terrestrial Chlorophyll Index) was used, thus indicating that MTCI was the most reliable index in mapping C ab in this forest environment. Empirical models based on optical indices were developed to map C ab from Multispectral Infrared and Visible Imaging Spectrometer (MIVIS) images acquired by an airborne survey on the Park forested area. A regression analysis between C ab concentration measured in leaves sampled in field and optical indices computed from hyperspectral MIVIS data was conducted. The MTCI index showed the highest performances and was therefore used to map C ab concentration of the Ticino Park oak forest. The C ab map was then used to assess crown discoloration level. 相似文献
958.
Giulio Concas Maria Ilaria Lunesu Michele Marchesi Hongyu Zhang 《Journal of Software: Evolution and Process》2013,25(12):1225-1248
A software maintenance process is important for reducing maintenance effort and for improving software quality. In recent years, the Lean–Kanban approach has been widely applied in software practice including software maintenance. This approach minimizes Work‐in‐Progress (WIP), which is the number of items that are worked on by the team at any given time, thus improving the maintenance process. In this paper, we describe our simulation studies, which show that the Lean–Kanban approach can indeed help reduce the average time needed to complete maintenance requests. We develop a process simulator that can simulate both existing maintenance processes that do not use a WIP limit and that adopt it. We perform two case studies using real maintenance data collected from a Microsoft project and from a Chinese software firm. The main results of our study are twofold. First, we demonstrate that it is possible to effectively model and simulate, using actors and events, a maintenance process where a flow of issues is processed through a sequence of activities, correctly reproducing key statistics of real data. Second, our results confirm that the WIP‐limited process could be useful to increase the efficiency of software maintenance, as reported in previous industrial practices. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
959.
The incidence of congenital cardiac abnormalities remains high. Paediatric patients with congenital cardiac defects often require surgery at a young age. The surgeries are often long and complex, rendering this population particularly vulnerable to the deleterious effects of cardiopulmonary bypass and cardiac surgery. The search for cardioprotective strategies is ongoing in an attempt to reduce the morbidity in this population. In the post-genomic era, it is apparent that simply determining the genomic sequences holds little diagnostic potential and means to determine progression of disease and response to treatment. The field of proteomics is expanding and application of proteomic techniques in the clinical setting holds great potential to advance our understanding of the proteomic changes involved in specific disease stages. This review will assess the application of proteomic techniques in the setting of paediatric cardiac surgery and highlight the need to obtain a clear understanding of the role of various proteins in children with cardiac conditions. The success and challenges of the available proteomic technology will be discussed as well as the future potential of proteomic methods for advancing our understanding of protein changes in children requiring cardiac surgery. 相似文献
960.
In this paper, a general frame to study relations between additive and multiplicative representations of rational matrix functions is presented. Various extensions of the positive real lemma, as well as of other classical factorization results, both in the continuous and discrete-time cases, are established. In the case of square factorizations, the map between solutions to an asymmetric algebraic Riccati equation and pairs of factors is shown to be a homeomorphism. In this framework, we also derive a geometric characterization of non-square factorizations. 相似文献