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31.
Katja Akgün Johanna Behrens Dirk Schriefer Tjalf Ziemssen 《International journal of molecular sciences》2022,23(22)
B cell-depleting therapies such as ocrelizumab (OCR) are highly effective in people with multiple sclerosis (MS). Especially at treatment start and initial infusion, infusion-related reactions (IRR) are a common adverse event. The relevance of acute changes of cell-depleting therapies on peripheral immune compartments and routine lab testing is important for clinical practice. We systematically analyzed routine blood parameters, detailed blood immunophenotyping and serum cytokine profiles in 45 MS patients starting on OCR. Blood samples were collected before and after corticosteroid premedication and directly after each OCR infusion of the first three ocrelizumab infusions. Blood B cells were rapidly depleted and accompanied only by a mild cytokine release at the first OCR infusion. Cytokine release was not significantly detectable from a third application in line with decreasing IRRs. B cell depletion was accompanied by short-lived changes in other immune cell populations in number, activation and cytokine secretion after each OCR infusion. Standard lab parameters did not show any clinically relevant changes. Our data demonstrate only mild changes during the first OCR infusion, which are not present any more during long-term treatment. 相似文献
32.
There is difficulty for distinguishing of river and shadow in Synthetic Aperture Radar (SAR) images. A method of river segmentation in SAR images based on wavelet energy and gradient is proposed in this paper. It mainly includes two algorithms: coarse segmentation and refined segmentation. Firstly, The river regions are coarsely segmented by the wavelet energy feature,and then refined segmented accurately by the gradient threshold which is got adaptively. The experimental results show the validity of the method, which provides a good foundation for targets detection above the river. 相似文献
33.
After a thorough review of some controllable parameters, which included field investigations, cavern dimensions, explosive,
rock strength etc., cut, contour, lifters and stoping holes were introduced for blasting cavern of nucleus submarine. These
design were conducted using a U. Langefors and B. Kihlstrom theory.
Supported by the Navy Cavern Project Foundation of China (02) 相似文献
34.
Shreyasee Das Nele Dewit Dirk Jacobs Yolande A. L. Pijnenburg Sjors G. J. G. In t Veld Salom Coppens Milena Quaglia Christophe Hirtz Charlotte E. Teunissen Eugeen Vanmechelen 《International journal of molecular sciences》2022,23(13)
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
35.
36.
Yuling Liu Shuhong Liu Cong Zhang Yong Du Jiong Wang Yiwei Li 《Journal of Phase Equilibria and Diffusion》2017,38(2):121-134
The Cu-Zr binary system is re-investigated via experiment and thermodynamic modeling. Four alloys were prepared by arc melting in order to check the controversial phase equilibria reported in the literature. Both as-cast and annealed alloys were examined by optical microscopy, x-ray diffraction and electron probe microanalysis, and the phase transformation temperatures were measured by differential scanning calorimetry. The intermetallic compounds, Cu24Zr13, Cu2Zr and Cu5Zr8, were demonstrated to be not the stable phases. Based on the literature information and present experimental data, the Cu-Zr system was critically evaluated by means of CALculation of PHAse Diagram approach. A set of self-consistent thermodynamic parameters was obtained, and the calculated phase diagram and thermodynamic properties are in a satisfactory agreement with the experimental data. 相似文献
37.
In this report, a combination of the diffusion multiple technique and the recently developed pragmatic numerical inverse method was employed for a high-throughput determination of interdiffusivity matrices in Co-Cr-FeMn-Ni high-entropy alloys (HEAs). Firstly, one face-centered cubic (fcc) quinary Co-Cr-Fe-Mn-Ni diffusion multiple at 1373 K was carefully prepared by means of the hot-pressing technique. Based on the composition profiles measured by the field emission electron probe micro analysis (FE-EPMA), the composition-dependent interdiffusivity matrices in quinary Co-Cr-Fe-Mn-Ni system at 1373 K were then efficiently determined using the pragmatic numerical inverse method. The determined interdiffusivities show good agreement with the limited results available in the literature. Moreover, the further comparison with the interdiffusivities in the lower-order systems indicates the sluggish diffusion effect in Co-Cr-Fe-Mn-Ni HEAs, which is however not observed in tracer diffusivities. In order for the convenience in further analysis, a generalized transformation relation among interdiffusivities with different dependent components in multicomponent systems was finally derived. 相似文献
38.
T. Karthikeyan Arup Dasgupta S. Saroja M. Vijayalakshmi 《Journal of Materials Engineering and Performance》2005,14(2):241-248
The successful replacement of the present generation of corrosion-resistant materials (nitric acid-grade stainless steel and
Ti) by Ti-5Ta-1.8Nb, which has better corrosion resistance, depends on its weldability characteristics. This article presents
the results of a study on the fabrication, qualification, and microstructural characterization of the welds. Welding was carried
out using the direct current electrode negative (DCEN) polarity tungsten inert gas (TIG) (manual) welding method with high-purity
Ar shielding. Testing was carried out as per the ASME standard (section IX, welding and brazing). Qualification tests found
that the weldment met the required properties. The weldment showed heterogeneous microstructures, which are rationalized based
on differences in phase transformation mechanisms that are dictated by the thermal cycles experienced by various microscopic
regions. The results, described in this article, confirm that the weldability of the developmental Ti-Ta-Nb alloy is excellent.
A preliminary evaluation of the corrosion behavior of the welds showed rates comparable to that of the base metal, establishing
that this alloy could be considered as an alternative material for use in highly corrosive environments. 相似文献
39.
Large-scale single-crystalline SnO2 nanocauliflowers were successfully synthesized using a hydrothermal growth method without any template. The samples were
characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy
(EDS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). FE-SEM images show that the
as-grown SnO2 nanocauliflowers are constructed of tetragonal prisms with a width of 500–600 nm. XRD, EDS, and SAED results indicate that
the as-grown SnO2 nanocauliflowers are single crystalline with the tetragonal rutile crystalline structure. The growth mechanism of SnO2 nanocauliflowers is also preliminarily discussed on the basis of different Sn(OH)62− concentrations, and it is found that Sn(OH)62− concentration plays an important role in determining the shape of the prepared SnO2. Room temperature photoluminescence was further carried out on SnO2 nanocauliflowers to investigate their optical properties. An intense blue luminescence centered at a wavelength of 424 nm
is observed in the as-grown SnO2 nanocauliflowers. 相似文献
40.
For the multi-item and small lot size production mode and single machine job shop scheduling sequence independent setup time, many setup times are difficult to estimate accurately, which influences the ability to achieve accurate production cycles and costs of products. The survey shows that the length of the setup time depends on the level of employee’s knowledge. Therefore, a method for determining the standard setup time quota based on the level of employees’ knowledge is proposed. First, an evaluation index system for the level of employee’s knowledge is built; the level of employee’s knowledge is estimated by the masses and experts fuzzy comprehension evaluation and entropy method. Second, the range and definition of the level of employees’ knowledge index are developed. Third, the relational model of the employee’s knowledge level and the level of employees’ knowledge index is constructed through the least squares method. Finally, an example application is presented to verify the feasibility and effectiveness of the proposed model. 相似文献