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91.
Leena Maunula Agnieszka Kaupke Petra Vasickova Kirsi Söderberg Iwona Kozyra Sava Lazic Wim H.M. van der Poel Martijn Bouwknegt Saskia Rutjes Kris A. Willems Rita Moloney Martin D'Agostino Ana Maria de Roda Husman Carl-Henrik von Bonsdorff Artur Rzeżutka Ivo Pavlik Tamas Petrovic Nigel Cook 《International journal of food microbiology》2013
In recent years, numerous foodborne outbreaks due to consumption of berry fruit contaminated by human enteric viruses have been reported. This European multinational study investigated possible contamination routes by monitoring the entire food chain for a panel of human and animal enteric viruses. 相似文献
92.
国家空间选择反映了国家治理的空间偏
好,通过在选定空间进行尺度建构,引发地方多
尺度空间重构。国家级新区作为一种基于地方的
国家空间选择策略,2010年以来得到学界广泛关
注。现有研究重点审视这一策略建构实施的过
程、机制和内在逻辑,对其如何嵌构并影响地
方空间重构的探讨尚不深入。本文以中国内陆首
个国家级新区——重庆两江新区为例,揭示其
在都市区北部的治理建构对产业和人口的多层
次空间影响,比照欧美20世纪90年代以来国家
空间选择向都市区尺度上移后在次区域层面形
成的新空间非均衡现象,从政策治理环境、地
方政府角色探讨了中国与欧美国家空间选择对地
方空间影响的异同,丰富了国家空间选择理论的
地方化理解。 相似文献
93.
This work reports tests performed to evaluate the stability of aqueous dispersions of inorganic oxide pigments with different specific surface areas, with the use of anionic and non-ionic surfactants and concentrators. Color mixtures of oxide compounds of blue, green, olive and brown with the unit cell spinel structure were used as pigments. The sodium salt of sulfosuccinic acid monoester, oxyethylenated nonylphenol and ethoxylated derivatives of lauryl alcohol, fatty alcohol and fatty amine were used as surfactants. The concentrators used were: poly(vinyl alcohol), the sodium salt of carboxymethyl cellulose as well as a water-based polyurethane oligomer. The highest dispersion efficiency was found for dispersed systems in which surfactant and concentrator were incorporated in the formula. The one containing the sodium salt of carboxymethyl cellulose or polyurethane oligomer with ethoxylated saturated fatty alcohol or fatty amine was found to be the most efficient. It was discovered that a higher dispersion efficiency corresponds to pigments with larger specific surface. The efficiency is also found to improve when the concentrator is an acrylic polymer or copolymer made up of two acrylic species. In this case, the concentrator interaction with the surfactant is more effective if the value of its boundary viscosity number is higher. This observation confirms the existence of interactions between macro-chains of the concentrator and surfactant molecules forming micelles with the pigment particles. 相似文献
94.
95.
96.
D. A. Kritskaya E. F. Abdrashitov V. Ch. Bokun A. N. Ponomarev A. V. Chernyak S. G. Vasil’ev V. I. Volkov 《Petroleum Chemistry》2011,51(8):644-651
The distribution of water and methanol and their self-diffusion coefficients (SDCs) in carbon-doped MF-4SK perfluorinated
membranes have been studied by NMR. It has been shown that at a concentration of 12–35 wt % in the external solution, the
methanol concentration inside the membrane is higher by a factor of 1.4–2 than that in the external solution and increases
with increasing the carbon phase content. It has been found that SDC values for water and methanol in the membrane decrease
with an increase in the C phase content. In a membrane with 23 wt % C, the SDC of methanol is reduced by a factor of 1.6.
It has been shown that the SDC of methanol in these membranes is below that of water by a factor of 1.5. The activation energies
of self-diffusion of water and methanol have been determined. It has been found that they remain almost unaffected by the
C content and have close values of 19–20 kJ/mol, which are 2–4 kJ/mol above the activation energy of self-diffusion of pure
water in these membranes. 相似文献
97.
Mallidis C Czerwiec A Filippi S O'Neill J Maggi M McClure N 《Reproduction (Cambridge, England)》2011,142(1):63-71
The synergistic effect of the co-morbidities that comprise metabolic syndrome (MetS) is increasingly being recognised as an important contributor in the pathology of a broad spectrum of seemingly disparate conditions. However, in terms of male reproductive function, beyond erectile dysfunction, little is known about the influence of this cohort (collectively or separately) on spermatogenesis and sperm quality. The aims of this study were to assess the reproductive tract of a MetS animal model for detrimental changes, to determine whether a group of compounds (advanced glycation end products and their receptor) known to cause cell dysfunction and DNA damage was present and assess whether hypogonadotropic hypogonadism was the main contributing factor for the changes seen. Animals fed a high-fat diet were found to have significantly increased cholesterol, triglycerides, blood glucose, mean arterial pressure and visceral fat levels. Although serum testosterone was decreased, no changes were seen in either testicular or epididymal histology. Immunolocalisation of N(ε)-carboxymethyl-lysine and the receptor for advanced glycation end products was found in the testes, epididymides and sperm of the two treated groups of animals; however, ELISA did not show any difference in protein levels. Similarly, assessment of sperm nuclear DNA (nDNA) fragmentation by acridine orange test did not find significant differences in nDNA integrity. We conclude that the minimal effect on spermatogenesis and sperm quality seen in our model is probably due to the moderate increase of blood glucose rather than the hypogonadism. 相似文献
98.
The mechanism of the environmentally important reaction between permanganate anion and trichloroethene (TCE) has been studied theoretically using modern DFT functional. It has been shown that IEFPCM/M05-2X/aug-cc-pVDZ theory level yields activation parameters and carbon isotopic fractionation factor in excellent agreement with the experimental data. Obtained results indicate that this reaction proceeds via the 3+2 mechanism with a very early transition state, in which the new C-O bonds are formed only in about 20%. An alternative, stepwise mechanism that involves initial formation of a single new C-O bond and a C-Mn bond, followed by rearrangement to the permanganate-TCE adduct, has been found to be more energetically demanding and in disagreement with the experimental isotopic fractionation. 相似文献
99.
Twenty Brochothrix thermosphacta strains tested for biogenic amines (BAs) production, formed histamine (6.6-16.2 mg/kg) and tyramine (18.7-35.4 mg/kg) but neither putrescine nor cadaverine. Six of the twenty strains were also investigated in respect of their influence on the synthesis of BAs by Escherichia coli, Pseudomonas sp., Proteus mirabilis and Lactobacillus sakei. In pure culture Escherichia coli produced all of the studied amines (histamine, tyramine, putrescine and cadaverine) with a total concentration of 167.7 mg/kg, P. mirabilis produced a total of 56.7 mg/kg histamine, tyramine and cadaverine, while Lactobacillus sakei and Pseudomonas sp. produced histamine and tyramine, totaling 37.9 and 35.2 mg/kg respectively. All B. thermosphacta promoted cadaverine production by Escherichia coli which increased by 12-68%, and some of them contributed to the appearance of this amine among the metabolites of Pseudomonas. The presence of B. thermosphacta decreased the potential ability of P. mirabilis to produce BAs. 相似文献
100.
Martyna Seta Katarzyna Hara
na Kaja Kasareo Daria Solarz-Keller Agnieszka Cudnoch-Jdrzejewska Tomasz Witko Zenon Rajfur Maciej Guzik 《International journal of molecular sciences》2022,23(24)
The human body’s natural protective barrier, the skin, is exposed daily to minor or major mechanical trauma, which can compromise its integrity. Therefore, the search for new dressing materials that can offer new functionalisation is fully justified. In this work, the development of two new types of dressings based on poly(3-hydroxyoctanoate) (P(3HO)) is presented. One of the groups was supplemented with conjugates of an anti-inflammatory substance (diclofenac) that was covalently linked to oligomers of hydroxycarboxylic acids (Oli-dicP(3HO)). The novel dressings were prepared using the solvent casting/particulate leaching technique. To our knowledge, this is the first paper in which P(3HO)-based dressings were used in mice wound treatment. The results of our research confirm that dressings based on P(3HO) are safe, do not induce an inflammatory response, reduce the expression of pro-inflammatory cytokines, provide adequate wound moisture, support angiogenesis, and, thanks to their hydrophobic characteristics, provide an ideal protective barrier. Newly designed dressings containing Oli-dicP(3HO) can promote tissue regeneration by partially reducing the inflammation at the injury site. To conclude, the presented materials might be potential candidates as excellent dressings for wound treatment. 相似文献