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251.
This paper deals with the approximate controllability problem for a class of linear neutral evolution systems with infinite delay in Banach spaces. Since the concerned system involves additional linear terms, the fundamental solution theory is used to describe the mild solutions. Based on the spectral analysis and the adjoint system, sufficient conditions for the approximate controllability of the concerned system are established. The rank condition is also shown when the control space is finite-dimensional. A practical example is given to show the application of the obtained results.
相似文献252.
AlMeraj Zainab Boujarwah Fatima Alhuwail Dari Qadri Rumana 《Universal Access in the Information Society》2021,20(1):121-138
Universal Access in the Information Society - The objective of this study is to evaluate the current state of accessibility of higher education institution websites in the State of Kuwait.... 相似文献
253.
Aqeel AHMED Muhammad WASIF Anis FATIMA Liming WANG Syed Amir IQBAL 《Frontiers of Mechanical Engineering》2021,16(2):298-314
Frontiers of Mechanical Engineering - The machining industry must maximize the machine tool utilization for its efficient and effective usage. Determining a feasible workpiece location is one of... 相似文献
254.
Rivas A Cerrillo I Granada A Mariscal-Arcas M Olea-Serrano F 《The Science of the total environment》2007,382(1):14-21
The widespread presence of organochlorine (OC) pesticides in human samples may be explained by the environmental exposure of the population. Foods are considered a constant source of exposure, despite compliance with maximum permitted residue levels. This study aimed to examine the relationship between nutritional habits of women in Southeast Spain and their serum concentrations of OCs. A semi-quantitative questionnaire was used to estimate the frequency of consumption of foods by two age groups of women, pre-menopausal (Pre-M) and post-menopausal (Post-M), and their serum pesticide levels were measured by gas chromatography (GC) with electron capture detector and confirmed by GC and mass spectrometry. The Pre-M group showed significantly higher serum concentrations of all OCs studied with the exception of DDE. The groups significantly differed in consumption of all food groups with the exception of fruit. In the Pre-M group, the mean serum p,p-DDT concentration was significantly associated with milk/yoghurt (p<0.045) and red meat (p<0.023), serum o,p-DDT with red meat (p<0.049), serum aldrin with eggs (p<0.038) and poultry (p<0.024), and serum DDE with eggs (p<0.025). In the Post-M group, serum lindane was associated with fresh and cured cheese (p<0.001), red meat (p<0.001) and white and oily fish (p<0.001), and both serum DDE and dieldrin were associated with fresh cheese, cured cheese, red meat, and white and oily fish (p<0.001). These results confirm foods as a source of human exposure to persistent organic molecules. Consideration should be given to the reduction of permitted residue levels to minimize this threat to human and animal health. 相似文献
255.
Saliha Alehyen Fatima Bensejjay Mohammed El Achouri Lourdez Pérez Maria Rosa Infante 《Journal of surfactants and detergents》2010,13(2):225-231
The solubilization and interaction of an azo-dye (methyl orange) with dodecyl trimethyl ammonium bromide and cationic gemini
surfactants in the series of alkanediyl α,ω-bis[(dimethyl alkyl ammonium)bromide)] referred to as (m-s-m), m = 10, 12, 14 and s = 2, 3, 4 were investigated by means of UV–Vis spectroscopy. Aggregation with the anionic dye was reflected by a hypsochromic
shift with a decrease in the intensity of the absorption band. The results also show a bathochromic shift followed by a sharp
increase in the intensity of the maximum absorption band λmax after the critical micellar concentration (CMC). This indicates that the dye solubility increased with increasing surfactant
concentration. It was also observed that the aggregation of surfactant and dye takes place at a surfactant concentration far
below the CMC of the individual surfactant. The effects of the chain length as well as the spacer length of gemini surfactants
on the critical aggregation concentration and CMC were also examined. Moreover, the partition coefficients between the bulk
water and surfactant micelles K
S and K
X as well as the Gibbs energies of distribution of dye between the bulk water and surfactant micelles were determined using
the pseudo-phase model. The effect of the hydrophobic chain length and spacer of gemini surfactants on the distribution parameters
is also reported. 相似文献
256.
Fatima Bisbal Jose Vicente Gil Daniel Ramón Pedro Vicente Martínez-Culebras 《European Food Research and Technology》2009,229(5):751-755
In the present study, ochratoxigenic mycobiota in cocoa beans was identified at species level by digestion of the ITS products
using the endonucleases HhaI, NlaIII and RsaI. Of the 132 isolates of Aspergillus section Nigri collected from cocoa beans, 89 were identified as A. tubingensis, 27 as A. niger, 10 as A. tubingensis-like and 6 as A. carbonarius. No variation was observed between RFLP patterns (C, N, T1 and T2) described previously for grape isolates and those of the
cocoa isolates analysed. With respect to OTA-producing fungi, a high percentage of black aspergilli (50.7%) was able to produce
OTA. Additionally, most of the OTA-producing isolates were of moderate toxigenicity, producing amounts of OTA from 10 μg g−1 to 100 μg g−1. Percentages of OTA-producing isolates in the A. niger aggregate were higher than in other substrates, ranging from 30% to 51.7%. Furthermore, the detected levels of OTA production
in the A. niger aggregate, particularly in A. tubingensis species was higher than in A. carbonarius, ranging from 0.7 μg g−1 to 120 μg g−1 (mean 24.55 μg g−1). Due to the high occurrence, percentage of ocratoxigenic isolates and their ability to produce OTA, isolates belonging to
the A. niger aggregate could be considered as the main cause of OTA contamination in cocoa beans used for manufacturing cocoa products. 相似文献
257.
Ionic liquid droplet as e-microreactor 总被引:1,自引:0,他引:1
Dubois P Marchand G Fouillet Y Berthier J Douki T Hassine F Gmouh S Vaultier M 《Analytical chemistry》2006,78(14):4909-4917
A powerful approach combining a droplet-based, open digital microfluidic lab-on-a-chip using task-specific ionic liquids as soluble supports to perform solution-phase synthesis is reported as a new tool for chemical applications. The negligible volatility of ionic liquids enables their use as stable droplet reactors on a chip surface under air. The concept was validated with different ionic liquids and with a multicomponent reaction. Indeed, we showed that different ionic liquids can be moved by electrowetting on dielectric (EWOD), and their displacement was compared with aqueous solutions. Furthermore, we showed that mixing ionic liquids droplets, each containing a different reagent, in "open" systems is an efficient way of carrying supported organic synthesis. This was applied to Grieco's tetrahydroquinolines synthesis with different reagents. Analysis of the final product was performed off-line and on-line, and the results were compared with those obtained in a conventional reaction flask. This technology opens the way to easy synthesis of minute amounts of compounds ad libitum without the use of complex, expensive, and bulky robots and allows complete automation of the process for embedded chemistry in a portable device. It offers several advantages, including simplicity of use, flexibility, and scalability, and appears to be complementary to conventional microfluidic lab-on-a-chip devices usually based on continuous-flow in microchannels. 相似文献
258.
L Gravina F Ruiz E Diaz JA Lekue A Badiola J Irazusta SM Gil 《Journal of the International Society of Sports Nutrition》2012,9(1):32-11
Background
Soccer is a form of exercise that induces inflammatory response, as well as an increase in free radicals potentially leading to muscle injury. Balanced nutritional intake provides important antioxidant vitamins, including vitamins A, C and E, which may assist in preventing exercise-related muscle damage. The purpose of the present study was to determine the effect of macro/micronutrient intake on markers of oxidative stress, muscle damage, inflammatory and immune response in female soccer players.Methods
Twenty-eight female players belonging to two soccer teams of the same professional soccer club participated in this study after being informed about the aims and procedures and after delivering written consent. Each team completed an 8-day dietary record and played one competition match the same week. Participants were divided into two groups: the REC group (who complied with recommended intakes) and the NO-REC group (who were not compliant). Laboratory blood tests were carried out to determine hematological, electrolytic and hormonal variables, as well as to monitor markers of cell damage and oxidative stress. Blood samples were obtained 24 h before, immediately after and 18 h after official soccer matches. Student t-test or Mann?CWhitney U-test was used to compare both groups throughout the match.Results
At rest, we observed that the REC group had higher levels of total antioxidant status (TAS), glutathione peroxidase (GPx), and lower levels of creatine kinase (CK) and lactate dehydrogenase (LDH) in comparison to the NO-REC group. Immediately after the match, levels of TAS, GPx, superoxide dismutase (SOD), LDH and % lymphocytes were higher and the % of neutrophils were lower in the REC group compared to the NO-REC group. These differences were also maintained 18 h post-match, only for TAS and GPx.Conclusions
Our data reveal an association between nutritional intake and muscle damage, oxidative stress, immunity and inflammation markers. The benefit of the intake of specific nutrients may contribute to preventing the undesirable physiological effects provoked by soccer matches. 相似文献259.
Al-bahrani Majid Raissan Ahmad Waqar Mehnane Hadja Fatima Chen Ying Cheng Ze Gao Yihua 《纳微快报(英文)》2015,7(3):298-306
Nano-Micro Letters - We applied the reduced graphene oxide/multi-walled carbon nanotubes/nickel oxide (RGO/MWCNTs/NiO) nanocomposite as the counter electrode (CE) in dye-sensitized solar cells... 相似文献
260.