The authors established a chromogen-based, double immunolabeling method using antibodies from the same species without any unwanted cross-reactivity. In addition, time-consuming staining steps were ...shortened by using polymer-based secondary antibodies. Taking advantage of the nature of the chromogen 3-amino-9-ethylcarbazole (AEC), which is used as a horseradish peroxidase substrate for antibody detection, the AEC-derived signals in the first color development were easily eliminated by alcohol treatment. Therefore, the signals from the first staining did not interfere with those from the subsequent second staining, which used the chromogen 3,3′-diaminobenzidine. The co-localization of antigens within the same cell could be confirmed using this method, because cell images of the individual dye staining steps could be obtained and developed. The images from each step could be expressed in pseudo-colors in a dark field by using a computer. As a result, merged images could be constructed that resembled the images acquired by the fluorescent immunolabeling technique. The resolution of this method enabled analysis of the coexpression of two antigens in the same cell in the same section. The authors have named this staining technique the elucidation of the coexpression of two antigens in a cell using antibodies from the same species (ECSS).
Achieving precision pointing performance plays a decisive role in future space missions. Pointing performance is specified by a set of requirements consisting of absolute, window- and stability-time ...errors. The European Cooperation for Space Standardization categorizes this set in the following pointing performance error indices: absolute performance error (APE), mean performance error (MPE), relative performance error (RPE), performance drift error (PDE) and performance reproducibility error (PRE). The analysis of pointing error indices in time-simulations is straightforward as error data time-series can be described by standard statistics. However, for design purposes there exists no method that can directly and systematically handle control loop performance in terms of window- and stability-time pointing error indices. In this article we extend the standard multi-objective
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control problem to explicitly take into account requirements on pointing error index performance. The main topic, however, is the derivation of a control design approach that subjects the closed-loop control system to only one matrix criterion, the
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-norm. Therefore an optimization is set up to map pointing error index requirements into closed-loop specifications. The advantage of this approach is that the derived closed-loop specifications serve as indicators for the direct identification of design drivers, limits of performance and eventually systematic design trade-offs. Unlike in multi-objective
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control design approaches, this can be done even before controller synthesis, and thus independently of the specified control problem feasibility. Moreover, the derived approach enables control design in the H
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closed-loop shaping framework. Thus, various design objectives including pointing performance and robustness can be treated with one matrix criterion.
Structural health monitoring (SHM) is certainly one of the key technologies required to achieve the goal for new space vehicles of having reduced maintenance costs with increased levels of safety. ...For the time being, sensor technology has reached a good technology readiness level, but the integration of these technologies into the design process of a space vehicle has not received much consideration. The present article aims at giving a reference about the existing technologies on the matter and an introduction to some of the key issues for the integration of a SHM system into the design process of future space vehicles. In addition, the accident that occurred to the space shuttle Columbia is analyzed in order to show how SHM could be effective for the improvement of safety in future space vehicles. Furthermore, since important changes to aeronautical design procedures have been introduced as a consequence of catastrophic events, the evolution of aeronautical design practices in parallel with accidents has been examined.
NF‐κB has been recognized as one of the factors responsible for the development of cancer; however, the mechanism by which high expression of NF‐κB contributes to the progression of human oesophageal ...squamous cell cancer (ESCC) is not fully understood. In our investigations, NF‐κBP65 was overexpressed in human ESCC tissues, especially in ESCC tissues with deep invasion and lymph node metastasis. Suppression of NF‐κBP65 by siRNA decreased the invasion and proliferation ability of EC9706 cells in vitro. Furthermore, siRNA‐mediated NF‐κBP65 knock‐down could lead to the downregulation of MMP‐9, a metastasis‐related gene. Reduced E‐cadherin is a hallmark of invasive carcinomas that have acquired epithelial–mesenchymal transition (EMT) phenotypes and Vimentin is another molecule that is used widely as a marker of the EMT. We found upregulation of E‐cadherin expression and downregulation of Vimentin was induced by NF‐κBP65 siRNA, which suggests that NF‐κBP65 siRNA could inhibit the invasion and proliferation ability of ECSS through attenuating the expression of MMP‐9 and EMT. Thus, ESCC NF‐κBP65 could be a useful target for cancer prevention and therapy.
On this article there is presented, in a general way, the specification of a project management platform for space projects. The main goal for this specification was to include the European ...Cooperation for Space Standardization standards and normative documents within the platform available for all projects during the entire life cycles. The platform's system was divided into its major areas, each one of these areas have features and functionalities that allow the users to effectively manage their activities and assignments.
Objective: To investigate the frequency of acute stroke in patients with a recent travel history and to analyse risk factors, stroke patterns and presence of a patent foramen ovale (PFO) in this ...patient group. Design: One-year prospective observational study. Setting: Single-centre study. Methods: Enrolling all patients presenting with a first cerebral ischaemia and complementing the usual history with a standardised travel history. Results: Of 338 patients with acute stroke, 42 had a positive travel history (PTH) (12.4%). Patients with a PTH were significantly younger (56.6 (SD 13) years) than patients (66.9 (13.2) years, p = 0.0001) with a negative travel history (NTH). Frequency of PFO in the PTH group (13; 44.8%) was significantly higher than in the NTH group (7; 10.8%) (p = 0.0001), even after patients were dichotomised into two age groups (younger and older than median of all patients: 31% v 6.1%, p = 0.007 and 13.8% v 4.6%, p = 0.022, respectively). PTH patients had fewer stroke risk factors (2.2 (1.4) v 3.3 (1.6), p = 0.0001) and a different risk profile with a lower frequency of diabetes (11.9% v 31.4%, p = 0.009), hypertension (52.4% v 78.7%, p = 0.0001), atrial fibrillation (7.1% v 22%, p = 0.025) and others (16.7% v 38.9%, p = 0.005). In contrast, PTH patients had significantly more cardioembolic (35.7% v 19.3%, p = 0.023) and cryptogenic strokes (50% v 19.9%, p = 0.0001) and more often ischaemia in the territory of the posterior cerebral artery (29.6% v 6.3%, p = 0.0001). Conclusions: The finding that more PTH patients had a PFO and a cardioembolic stroke pattern but that fewer had other typical stroke risk factors led to the hypothesis that PFO is a risk factor for economy class stroke syndrome.
Future satellite missions have high precision pointing performance requirements. This leads to the necessity of optimizing attitude estimators not only with respect to absolute, but also with respect ...to window- and stability-time errors. These errors are especially important for achieving unprecedented image quality. The standard attitude estimator is designed to be optimal with respect to its absolute knowledge error. In practice, such an estimator design is either assumed to be almost optimal for window- and stability-time errors or a cumbersome simulation-based optimization is conducted to achieve optimality in this respect. The first assumption is not sufficient for high precision pointing missions and simulation-based design is computationally expensive. In this article frequency-domain metrics are used to develop a continuous-time design approach for a fixed gain attitude estimator that is optimized with respect to window- or stability-time errors. Colored noise is explicitly taken into account in the optimization because its spectrum strongly affects the solution. However, that might lead to instability of the estimator. This issue is addressed and a solution is provided that guarantees stability with the burden of marginal performance losses only. The approach is applied to design a two-state attitude estimator and its results are verified in frequency-domain computations and time-domain simulations for the future ESA mission, Meteosat Third Generation. In this case, the computational time for optimizing the window-time error has been reduced from hours to a few seconds. The fast and high precision estimator design for window- and stability-time errors thus supports time-efficient design trade-offs.
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