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1.
Growth of aerobic mesophilic bacteria in mixed salad without dressing, containing cooked sweet corn and raw endive, was similar to that of raw endive alone. At 9°C, sweet corn permitted the growth of the lactic acid bacterium Leuconostoc mesenteroides , whenever the bacterium was present on raw endive, whereas no growth of lactic acid bacteria was recorded on raw endive alone. Listeria monocytogenes , artificially inoculated in the samples, grew more in the mixed salad than in the raw endive alone, for products stored at 6°C and 9°C. Acidification of sweet corn to pH 5.0 was proposed to reduce the development of L. monocytogenes in the mixed salad to a level similar to that recorded in the raw endive alone. Acidification with citric acid reduced spoilage of sweet corn, whereas acetic acid caused necrosis on the leaves of raw endive.  相似文献   
2.
With the recent availability of commercial plasma-generating devices capable of reliable performance at powers as high as 30 MW, the applications of plasma technology in high-temperature extractive metallurgy are rapidly increasing. Some of the more promising process developments are reviewed in this paper, as are newer reactor designs.  相似文献   
3.
Neurofilament light chain (Nf-L) is a well-known biomarker for axonal damage; however, the corresponding circulating Nf-L analyte in cerebrospinal fluid (CSF) is poorly characterized. We therefore isolated new monoclonal antibodies against synthetic peptides, and these monoclonals were characterized for their specificity on brain-specific intermediate filament proteins. Two highly specific antibodies, ADx206 and ADx209, were analytically validated for CSF applications according to well-established criteria. Interestingly, using three different sources of purified Nf-L proteins, a significant impact on interpolated concentrations was observed. With a lower limit of analytical sensitivity of 100 pg/mL using bovine Nf-L as the calibrator, we were able to quantify the Nf-L analyte in each sample, and these Nf-L concentrations were highly correlated to the Uman diagnostics assay (Spearman rho = 0.97, p < 0.001). In the clinical diagnostic groups, the new Nf-L ELISA could discriminate patients with Alzheimer’s disease (AD, n = 20) from those with frontotemporal lobe dementia (FTD, n = 20) and control samples with subjective cognitive decline (SCD, n = 20). Henceforth, this novel Nf-L ELISA with well-defined specificity and epitopes can be used to enhance our understanding of harmonizing the use of Nf-L as a clinically relevant marker for neurodegeneration in CSF.  相似文献   
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5.
In case of an incident in the nuclear industry or an act of war or terrorism, the dissemination of plutonium could contaminate the environment and, hence, humans. Human contamination mainly occurs via inhalation and/or wounding (and, less likely, ingestion). In such cases, plutonium, if soluble, reaches circulation, whereas the poorly soluble fraction (such as small colloids) is trapped in alveolar macrophages or remains at the site of wounding. Once in the blood, the plutonium is delivered to the liver and/or to the bone, particularly into its mineral part, mostly composed of hydroxyapatite. Countermeasures against plutonium exist and consist of intravenous injections or inhalation of diethylenetetraminepentaacetate salts. Their effectiveness is, however, mainly confined to the circulating soluble forms of plutonium. Furthermore, the short bioavailability of diethylenetetraminepentaacetate results in its rapid elimination. To overcome these limitations and to provide a complementary approach to this common therapy, we developed polymeric analogs to indirectly target the problematic retention sites. We present herein a first study regarding the decontamination abilities of polyethyleneimine methylcarboxylate (structural diethylenetetraminepentaacetate polymer analog) and polyethyleneimine methylphosphonate (phosphonate polymeric analog) directed against Th(IV), used here as a Pu(IV) surrogate, which was incorporated into hydroxyapatite used as a bone model. Our results suggest that polyethylenimine methylphosphonate could be a good candidate for powerful bone decontamination action.  相似文献   
6.
FeVO4 was synthesised by conventional solid state technique. Impedance measurements using a silver electrode were unsuccessful due to a solid state reaction between FeVO4 and Ag, forming α-AgVO3 and α-Fe2O3 at the interface. Impedance measurements, with a platinum electrode, reaffirmed that FeVO4 exhibits semiconductor behaviour in air. In a reducing atmosphere, 5% H2/Ar, high electronic conductivity, from 1 S cm−1 at 300 °C to 2 S cm−1 at 700 °C, was observed with an activation energy of 0.13(1) eV. X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry data determined that the change in electronic conductivity was due to the degradation of the material into FeV2O4 and α-Fe2O3. It is believed that the conduction was due to electron hopping between vanadium d-orbitals. Neither FeVO4 nor FeV2O4 are deemed suitable as anode materials for solid oxide fuel cells, due to redox instability.  相似文献   
7.
We address the problem of the segmentation of cerebral white matter structures from diffusion tensor images (DTI). A DTI produces, from a set of diffusion-weighted MR images, tensor-valued images where each voxel is assigned with a 3 x 3 symmetric, positive-definite matrix. This second order tensor is simply the covariance matrix of a local Gaussian process, with zero-mean, modeling the average motion of water molecules. As we will show in this paper, the definition of a dissimilarity measure and statistics between such quantities is a nontrivial task which must be tackled carefully. We claim and demonstrate that, by using the theoretically well-founded differential geometrical properties of the manifold of multivariate normal distributions, it is possible to improve the quality of the segmentation results obtained with other dissimilarity measures such as the Euclidean distance or the Kullback-Leibler divergence. The main goal of this paper is to prove that the choice of the probability metric, i.e., the dissimilarity measure, has a deep impact on the tensor statistics and, hence, on the achieved results. We introduce a variational formulation, in the level-set framework, to estimate the optimal segmentation of a DTI according to the following hypothesis: Diffusion tensors exhibit a Gaussian distribution in the different partitions. We must also respect the geometric constraints imposed by the interfaces existing among the cerebral structures and detected by the gradient of the DTI. We show how to express all the statistical quantities for the different probability metrics. We validate and compare the results obtained on various synthetic data-sets, a biological rat spinal cord phantom and human brain DTIs.  相似文献   
8.
Ubiquitous computing applications or widespread robots interactions execute in unforeseen environments and need to adapt to changeful available services, user needs, and variations of the environment. Context-awareness ability addresses such a need, enabling, through adaptation rules, applications to react to the perceived dynamic variations. Responses to adaptation have to be quick enough to maximize the time during which the application is coherent with its environment. Adaptation rules, associating variations of the environment to application reactions, are usually established at design time. However, in unforeseen and partially anticipated environments, we claim that adaptation rules have to be dynamically extensible to match previously unexpected variations. Our approach enables rule composition and ensures a deterministic result. We propose to use parameter adaptation to quickly respond to environmental variations and dynamic compositional adaptation to provide extensibility to the parameter adaptation. To foster even lower response times, we internalize context-awareness processing and decision into the application.  相似文献   
9.
The influence of the interface of the dielectric SiO2 on the performance of bottom‐contact, bottom‐gate poly(3‐alkylthiophene) (P3AT) field‐effect transistors (FETs) is investigated. In particular, the operation of transistors where the active polythiophene layer is directly spin‐coated from chlorobenzene (CB) onto the bare SiO2 dielectric is compared to those where the active layer is first spin‐coated then laminated via a wet transfer process such that the film/air interface of this film contacts the SiO2 surface. While an apparent alkyl side‐chain length dependent mobility is observed for films directly spin‐coated onto the SiO2 dielectric (with mobilities of ≈10?3 cm2 V?1 s?1 or less) for laminated films mobilities of 0.14 ± 0.03 cm2 V?1 s?1 independent of alkyl chain length are recorded. Surface‐sensitive near edge X‐ray absorption fine structure (NEXAFS) spectroscopy measurements indicate a strong out‐of‐plane orientation of the polymer backbone at the original air/film interface while much lower average tilt angles of the polymer backbone are observed at the SiO2/film interface. A comparison with NEXAFS on crystalline P3AT nanofibers, as well as molecular mechanics and electronic structure calculations on ideal P3AT crystals suggest a close to crystalline polymer organization at the P3AT/air interface of films from CB. These results emphasize the negative influence of wrongly oriented polymer on charge carrier mobility and highlight the potential of the polymer/air interface in achieving excellent “out‐of‐plane” orientation and high FET mobilities.  相似文献   
10.
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