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Suppression of inflammatory gene expression in T cells by Porphyromonas gingivalis is mediated by targeting MAPK signaling

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Cellular & Molecular Immunology 2013年第5期10卷 413-422页

作者： Hazem Khalaf Isak Demirel Torbjorn bengtsson Division of Clinical Medicine School of Health and Medical Sciences Orebro University Orebro Sweden

There is increasing awareness of the effects of Porphyromonas gingivalis on host immune responses. Degradation of cytokines and chemokines by cysteine proteinases has previously been reported. However, the precise mechanisms by which P. gingivalis is able to alter intracellular signaling, and thus proliferation and inflammation, have not been descri bed. We have previously reported s u ppression of activator protei n-1 （AP-1） and degradation of I L-2 by protei nases from P. gingivalis. In the present study, we have analyzed the effects of P. gingivalis on Jurkat T-cell signal transduction and subsequent IL-2 and CXCL8 expression. We found that CXCL8, but not IL-2, gene expression levels were significantly suppressed by viable P. gingivalis. Analysis of intracellular signaling revealed an inhibitory effect of P. gingivalis on c-Jun and c-Fos, but not NFκB（p50and p65）, NFATor STAT5expression. This inhibitory effect was not due to suppression of mitogen-activated protein kinase （MAPK）（p38, erkand JNK） gene expression, but was rather due to prevention of protein kinase C （PKC） and p38 phosphorylation, as demonstrated by western blot analysis. Furthermore, SOCS1 and SOCS3 expression levels decreased following treatment of Jurkat T cells with viable P. gingivalis. The results indicate that P. gingivalis is able to suppress inflammatory gene expression by targeting the activity of MAPK pathways in T cells, which was confirmed by using specific inhibitors of NF-κB, PKC, ERK, p38 and JNK.

关键词： MAPK Porphyromonas gingivalis protei nases T cells

Towards a holistic user innovation policy

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International Journal of Innovation Studies 2022年第1期6卷 35-52页

作者： Lars bengtsson Charles Edquist Division of Innovation Engineering Department of Design SciencesFaculty of Engineering e LTHLund University22100 LundSweden CIRCLE Lund University22100 LundSweden

This paper aims to synthesize previous user innovation policy proposals into an adapted system of innovation framework,on which a future holistic user innovation policy for the household sector can be *** do this in three ***,we introduce the systems of innovation framework as a comprehensive basis for a holistic approach to innovation ***,we identify and review policy proposals made by user innovation researchers and categorize them according to ten key activities in the systems of innovation ***,from a system of innovation perspective,we synthesize the policy proposals identified into an adapted framework,including determinants specific to user innovation in the household *** synthesized proposals are intended to strengthen the systemic and multi-causal effects of policy on household sector user innovation in a country,region,or *** policies for user innovation may,on this basis,be instrumental in avoiding mono-causality,or the concentration on only a few policy instruments in a proposed policy.

关键词： User innovation Household sector Systems of innovation Innovation policy Holistic innovation policy

Implementation of Control Algorithms in Small Embedded Systems

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Engineering（科研） 2020年第9期12卷 623-639页

作者： Lars bengtsson Department of Physics University of Gothenburg Gothenburg Sweden

This work describes how a control algorithm can be implemented in a small (8-bit) microcontroller for the main purpose of merging embedded systems and control theory in electrical engineering undergraduate classes. Two different methods for discretizing the control expression are compared: Euler transformation and bilinear transformation. The sampling rate’s impact on the algorithm is discussed and theoretical results are verified by an application to a temperature control system in a heating plant. Four control algorithms are compared: PID and PI algorithms discretized with Euler and bilinear transformation, respectively. It is shown that for the heating plant used in this work, a bilinear PI algorithm implemented in a small 8-bit microcontroller outperforms a commercial controller from Panasonic. It is also demonstrated that all the derived algorithms can be implemented using integer calculations only, obviating the need for expensive and time-consuming floating-point calculations. This work bridges the gap between control theory equations and the implementation of control systems in small embedded systems with no inherent floating-point processing power.

关键词： Bilinear Transformation Euler Transformation Microcontroller Control System PID Algorithm Temperature Sensor Set Value Process Value Plant

Segmentation and Tracking of Neural Stem Cell

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Chinese Journal of Biomedical Engineering(English Edition) 2005年第3期14卷 93-103页

作者： Ewert bengtsson Information & Communication Institute Harbin Engineering UniversityHarbin 150001China

In order to understand the development of stem cells into specialized mature cells it is necessary to study the growth of cells in culture. For this purpose it is very useful to have an efficient computerized cell tracking system. In this paper a prototype system for tracking neural stem cells in a sequence of images is described. In order to get reliable tracking results it is important to have good and robust segmentation of the cells. To achieve this we have implemented three levels of segmentation. The primary level, applied to all frames, is based on fuzzy threshold and watershed segmentation of a fuzzy gray weighted distance transformed image. The second level, applied to difficult frames where the first algorithm seems to have failed, is based on a fast geometric active contour model based on the level set algorithm. Finally, the automatic segmentation result on the crucial first frame can be interactively inspected and corrected. Visual inspection and correction can also be applied to other frames but this is generally not needed. For the tracking all cells are classified into inactive, active, dividing and clustered cells. Different algorithms are used to deal with the different cell categories. A special backtracking step is used to automatically correct for some common errors that appear in the initial forward tracking process.

关键词： Tracking Stem cells Level set Time lapse image sequence

Patient Characteristics, Safety, and Tolerability With Telaprevir Treatment for HCV in the Clinic:a Retrospective, Multicenter Study

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Journal of Clinical and Translational Hepatology 2014年第2期2卷 65-73页

作者： Steven L. Flamm Paul J. Pockros Leif bengtsson Mark Friedman Northwestern University Feinberg School of Medicine Chicago Illinois USA Scripps Clinic and Scripps Translational Science Institute La Jolla California USA Vertex Pharmaceuticals Incorporated Boston Massachusetts USA

Background and Aims: There is a paucity of information regarding similarities and differences between patients from the phase 3 studies of telaprevir and those receiving telaprevir in clinical practice. Methods: This retrospective chart review evaluated baseline characteristics and follow-up safety and tolerability data for patients with hepatitis C virus (HCV) infection treated with telaprevir and peginterferon alfa and ribavirin (PR) in clinical practice. Results: In total, 338 charts from patients at four academic and three community US treatment centers who received telaprevir and PR and had at least 12 weeks of follow-up data were included;62%were from academic centers and 38% were from community centers. Of the 338 patients, 269 completed 12 weeks of telaprevir and PR;32 discontinued due to adverse events. Mean age was 55 years;patients were predominantly white (79.3%) males (58.9%) with genotype 1a HCV infection (61.8%);35.5%were reported to have cirrhosis at baseline;and 55.3%previously received PR. Hypertension and depres-sion were the most common comorbidities. Patient charac-teristics outside the per-protocol minimum criteria used in the phase 3 studies of telaprevir were, e.g., hemoglobin, 9.2%;albumin, 5.3%;platelets, 11.5%;and neutrophil count, 5.6%. Adverse events occurred in 329/338 (97.3%) patients, with anemia, fatigue, nausea, and rash being the most common. Of 38 hospitalizations, 26 were deemed related to telaprevir and PR. Three patients died due to pneumonia, septic shock, and hepatorenal syndrome (n=1 each). Conclusions: These findings complement those reported from rigorous, randomized controlled studies with telaprevir-based treatment and provide a general assess-ment of similarities and/or differences between patients from the phase 3 studies of telaprevir and those treated with telaprevir in clinical practice.

关键词： Hepatitis C virus Combination drug therapy Protease inhibitors Liver diseases

Lookup Table Optimization for Sensor Linearization in Small Embedded Systems

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Journal of Sensor Technology 2012年第4期2卷 177-184页

作者： Lars E. bengtsson Physics Department University of Gothenburg Gothenburg Sweden

This paper treats the problem of designing an optimal size for a lookup table used for sensor linearization. In small embedded systems the lookup table must be reduced to a minimum in order to reduce the memory footprint and intermediate table values are estimated by linear interpolation. Since interpolation introduces an estimation uncertainty that increases with the sparseness of the lookup table there is a trade-off between lookup table size and estimation precision. This work will present a theory for finding the minimum allowed size of a lookup table that does not affect the overall precision, i.e. the overall precision is determined by the lookup table entries’ precision, not by the interpolation error.

关键词： Lookup Table Sensor Linearization Embedded Systems Interpolation

The Highest Practical Good and the Ethical Demand:Lines of Development in Phenomenological Ethics

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The Highest Practical Good and the Ethical Demand:Lines of D...

作者： Jan bengtsson 瑞典Gteborg大学教育系

The phenomenological tradition is today one of the leading research traditions in the *** although ethics is a central issue in contemporary philosophy as well as in the social sciences,especially in education,the contributions of phenomenology to ethics are little *** purpose of this article is,therefore,to explore the history of phenomenological ethics and make its results available for the ongoing discussion of *** is possible to outline the history of phenomenological ethics in two different main *** of them is a value theoretical line and its central concept is "the highest practical good".This line of thought has its origin in the philosophy of Franz Brentano and its leading representative is Max *** second line of phenomenological ethics is normative and its basic concept is "the ethical demand".This line of thought has Edmund Husserl as its originator and its foremost representatives are Knud Ejler Lφgstrup and Emmanuel *** are,however,also several other approaches in phenomenological ethics,which for different reasons have not had the same influence as the two principal lines of *** excursions from the main lines are,therefore,necessary to make.

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数值天气预报的进展和展望

气象科技 1993年第1期21卷 18-24页

作者： L.bengtsson 程翠娥欧洲中期天气预报中心

该文系统地回顾了近10—15年来中期数值天气预报在数值模拟,资料同化,业务预报技巧,模式系统误差方面的研究进展。着重介绍了欧洲中期天气预报中心(ECMWF)业务预报模式和资料同化系统的主要变化。最后,对数值天气预报的未来前景作一展望。

关键词：天气预报数值天气预报发展

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螺旋齿轮与正齿轮的表面致密化

粉末冶金技术 2009年第1期27卷 67-73页

作者： Sven bengtsson Linnéa Fordén Magnus Bergstrm Claes Kuylenstierna 亓家钟 Hgans A B Sweden Scania C V Sweden Volvo Trucks Materials Technology Sweden

过去几十年,用于汽车的粉末冶金零件不断增长,对零件性能的要求也越来越高。汽车用的变速器齿轮的形状复杂,按照齿轮质量要求(DIN,ISO,AGMA等)几何精度很高,按齿面与齿根的耐久性要求力学性能也很高。对于制造复杂形状零件,粉末冶金法... 详细信息

过去几十年,用于汽车的粉末冶金零件不断增长,对零件性能的要求也越来越高。汽车用的变速器齿轮的形状复杂,按照齿轮质量要求(DIN,ISO,AGMA等)几何精度很高,按齿面与齿根的耐久性要求力学性能也很高。对于制造复杂形状零件,粉末冶金法对控制成本很有效。通过增加对齿的选择性致密化,在增加很少费用下就能满足精度与力学性能要求。由压制、烧结、碾压致密化及最后热处理组成的工艺路线,可评估用粉末冶金制造的变速器齿轮的可行性。在研究中所用的螺旋齿轮与正齿轮,对致密化及所得到的齿轮的质量与齿根疲劳都进行了试验。

关键词：螺旋齿轮正齿轮表面致密化齿轮质量齿根疲劳