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Are polymorphisms of the SDF1 and CCR2b genes related to the course of hepatitis C or HIV/HCV co-infection?

DEUTSCHE MEDIZINISCHE WOCHENSCHRIFT 2002年第36期127卷 1807-1812页

作者： Woitas, RP Ahlenstiel, G Iwan, A Rockstroh, JK Brackmann, HH Kupfer, B Matz, B Offergeld, R Sauerbruch, T Spengler, U Univ Bonn Med Klin & Poliklin 1 D-53105 Bonn Germany Univ Bonn Inst Expt Hamatol & Transfus Med D-53105 Bonn Germany Univ Bonn Inst Med Mikrobiol & Immunol D-53105 Bonn Germany

Background and objective: Complementary to the CCR5-Delta32 mutation polymorphisms in the genes of CCR2b (CCR2b-V64 I) and stromal derived factor (SDF)-1 (SDF-1 3'A) affect the course of the human immunodeficiency virus (HIV) infection. While the CCR5-Delta32 mutation is also increased in chronic hepatitis C virus (HCV) infection it is unclear, whether the CCR2b-V64 I and the SDF-1 3'A polymorphisms also are associated with chronic HCV infection. Methods: We analyzed the frequencies of the CCR2b-V64I and SDF1-3'A mutation in patients with HIV/HCV coinfection (n = 130), HIV infection (n = 105), HCV infection (n = 153) and 112 healthy blood donors. We stratified each group into homozygous mutations, heterozygous mutations and homozygous wildtypes, respectively. The resulting subsets were compared with respect to HIV and HCV loads, CD4 and CD8 cell counts. Results: The mutant SDF1-3'A allele was found at 20.3% frequency in patients with HCV infection and at 20.4% frequency in patients with HIV/HCV coinfection, respectively. It was present in 27.1% of the patients with HIV infection and 27.9% of the healthy controls (not significant). The number of SDF-1 3'A homozygous patients was highest in patients with HIV/HCV coinfection and significantly different compared to the Hardy-Weinberg equilibrium (p = 0.010, chi(2) = 9.15). However, CD4- and CD8-cell counts or viral loads were not affected by this mutation. The frequency of the CCR2b-V64 I allele was similar in all patient groups. However, CCR2b-V64 I heterozygous patients showed HIV loads that were threefold lower than in CCR2b wildtype patients (22.9 x 10(3) vs. 6.4 x 10(3) copies/ml, not significant). Furthermore, hepatitis C viral loads were reduced roughly by 30%. Conclusion: These results suggest that the SDF1-3'A and CCR2b-V64I mutations do not affect the course of HCV and HIV/HCV infection in the same manner as does the CCR5-Delta32 mutation.

关键词： Human immunodeficiency virus infection diagnosis Human immunodeficiency virus infection drug therapy HIV Infections CXCL12 gene density estimation robust algorithm Mutation HIV Hepatitis C COL14A1 gene CD8-Positive T-Lymphocytes Patients Chemokine CXCL12

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A METHODOLOGY FOR THE FAST AND TESTABLE IMPLEMENTATION OF STATE DIAGRAM SPECIFICATIONS

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IEEE JOURNAL OF SOLID-STATE CIRCUITS 1985年第2期20卷 548-554页

作者： SPAANENBURG, L SMIT, J VANDERVEEN, H Department of Electronic Engineering Twente Technical University Enschede Netherlands

A methodology is presented for the hierarchical structured design of state diagram specifications. It is based on a set of restrictions on the composition of the hierarchy that allows a design to be proven correct by construction. Furthermore, silicon primitives are introduced that permit a direct mapping of asynchronous and synchronous state diagrams. Special attention is paid to the use of scanpath testability enhancement. The design methodology and implementation technique combined facilitate a fast and area efficient integration of control structures. From the development of a DRAM controller IC, it is shown how layout design can be automated through several phases of standard cell design, permitting silicon compilation in the near future.

关键词： Logic testing Logic design CMOS logic circuits Design methodology Automatic control Random access memory Silicon Monitoring density estimation robust algorithm Integrated circuit layout

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The effect of regeneration on the received signal strength

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PROCEEDINGS OF THE INSTITUTE OF RADIO ENGINEERS 1928年第8期16卷 1045-1052页

作者： van der Pol, B Philips Glowlamp Works Ltd Phys Lab Eindhoven HOLLAND

It is the purpose of this paper to give a theory of the effect of regeneration using the solution of a non-linear differential equation, and to present experimental verification of the theory. It is shown that: (a) as a first approximation, detection has no effect on the radio-frequency grid voltage developed under the influence of an incoming signal, (b) the amplification obtained through regeneration equals the two-thirds power of the ratio of the "grid space" to the amplitude obtained with zero regeneration. It is apparent from (b) that much greater gain is obtained through regeneration with weak signals than with strong signals. The verification of the theory is made with a circuit arrangement operating at 500 cycles per second. Application is made to radio frequencies using this as a model of a high-frequency system, following a theorem for model systems which is stated.

关键词： Anodes Radio frequency Voltage density estimation robust algorithm Laboratories Differential equations RLC circuits Tuned circuits Silicon compounds Transconductance

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Cytokine receptor common β chain as a potential activator of cytokine withdrawal-induced apoptosis

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MOLECULAR AND CELLULAR BIOLOGY 1999年第11期19卷 7399-7409页

作者： Lee, SF Huang, HM Chao, JR Lin, S Yang-Yen, HF Yen, JJY Acad Sinica Inst Biomed Sci Taipei 11529 Taiwan Acad Sinica Inst Mol Biol Taipei 11529 Taiwan Natl Def Med Ctr Grad Inst Life Sci Taipei Taiwan Fu Jen Catholic Univ Grad Inst Biol Taipei Taiwan

Growth factors and cytokines play an important role in supporting cellular viability of various tissues during development due to their ability to suppress the default cell death program in each cell type. To date, neither the triggering molecule nor the transduction pathway of these default apoptosis programs is understood. In this study, we explored the possibility that cytokine receptors are involved in modulating cytokine withdrawal-induced apoptosis (CWIA) in hematopoietic cells. Expression of the exogenous cytokine receptor common beta chain (beta c), but not the alpha chains, accelerated CWIA in multiple cytokine-dependent cell lines. Reduction of the expression level of endogenous beta c by antisense transcripts resulted in prolonged survival during cytokine deprivation, suggesting a critical role of beta c in modulating CWIA. Fine mapping of the beta c subunit revealed that a membrane-proximal cytoplasmic sequence, designated the death enhancement region (DER), was critical to the death acceleration effect of beta c. Furthermore, DER accelerated cell death either as a chimeric membrane protein or as a cytosolic protein, suggesting that DER functions independently of the cytokine receptor and membrane anchorage. Cross-linking of the chimeric membrane-bound DER molecules by antibody or of the FK506-binding protein-DER fusion protein by a synthetic dimerizing agent, AP1510, did not abrogate the death acceleration effect. Transient transfection assays further indicated that DER promoted cell death in the absence of serum in the nonhematopoietic 293 cell line. In summary, our data suggest that beta c plays an important role in modulating CWIA via an anchorage-independent and aggregation-insensitive mechanism. These findings may facilitate further studies on the signaling pathways of CWIA.

关键词： Cytokine Receptors Cell Line Cell Death density estimation robust algorithm Cytokines cell type

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ITERATIVE APPROACH TO THE FREQUENCY-DOMAIN SOLUTION OF THE INVERSE-SCATTERING PROBLEM FOR AN INHOMOGENEOUS LOSSLESS DIELECTRIC SLAB

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 1984年第7期32卷 711-716页

作者： TIJHUIS, AG VANDERWORM, C Laboratory of Electromagnetic Research Department of Electrical Engineering Delft University of Technnology Delft Netherlands

A previously developed time-domain iterative inverse-scattering method is generalized to the problem of reconstructing the susceptibility of an inhomogeneous lossless dielectric slab from frequency-domain reflection data. In subsequent iteration steps, approximations for the electric field inside the slab and the unknown susceptibility profile are obtained by alternately solving an approximate direct-scattering problem and an approximate inverse-scattering problem. Numerical results are presented and discussed.

关键词： Dielectric losses Iterative methods Slabs Electromagnetic scattering Particle scattering Frequency Nonuniform electric fields Dielectric loss measurement Electromagnetic reflection density estimation robust algorithm

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TRENCH SIDEWALL IMPLANTATION WITH A PARALLEL SCANNED ION-BEAM

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IEEE TRANSACTIONS ON ELECTRON DEVICES 1990年第4期37卷 1052-1056页

作者： KAKOSCHKE, R KAIM, RE VANDERMEULEN, PFHM WESTENDORP, JFM VARIAN EXTRION DIV BEVERLYMA 01915

The sidewalls of trenches on 100-mm wafers were doped by implantation with an implanter whose beam scan is accurately parallel over the whole wafer surface. The doping was characterized with a staining technique and transmission electron microscopy. All the trenches exhibited symmetrical doping, with the main differences between trenches from the center and edge of a wafer being due to nonuniformity of the trench etching rather than the implant step. Although the measurements were made on 100-mm wafers, symmetrical doping should be achievable for all trenches on wafers up to 200 nm in diameter.< >

关键词： Ion beams Implants Doping Very large scale integration Random access memory density estimation robust algorithm Transmission electron microscopy Etching Circuits Capacitors

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RELATIONSHIP BETWEEN TEMPERATURE BEHAVIOR OF RESONANT AND ANTIRESONANT FREQUENCIES AND ELECTROMECHANICAL COUPLING FACTORS OF PIEZOELECTRIC RESONATORS

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PROCEEDINGS OF THE IEEE 1969年第4期57卷 702-&页

作者： ONOE, M University of Tokyo Roppongi Tokyo Japan

A relationship between temperature behavior of the resonant frequency FR, the antiresonant frequency FA, and the coupling factor k is given by an equation of the form FA/FA- FR/FR= Gk/k. The factor G as a function of the coupling factor and the order of overtone is calculated for both piezoelectrically unstiffened and stiffened modes. An application of this relationship yields the curve of turnover temperature versus the coupling factor of X-cut lithium tantalate resonators.

关键词： Resonance Resonant frequency Equations Lithium compounds density estimation robust algorithm Temperature dependence Aging Capacitance

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BASE RESISTANCE IN I-2-L STRUCTURES - ITS DETERMINATION AND ITS INFLUENCE ON UPWARD CURRENT GAIN

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IEEE JOURNAL OF SOLID-STATE CIRCUITS 1982年第4期17卷 783-786页

作者： KOOPMANS, JM VANDERMEIJ, CJ Department of Electrical Engineering Delft University of Technnology Delft Netherlands

A sectionalized structure-oriented model is used for the description of the DC behavior of a multicollector integrated injection logic (I/SUP 2/L) gate. The model includes high-injection effects in the p-n-p transistor base and lateral base resistance in the n-p-n transistor. Methods for measuring the base resistance are outlined. The validity of the obtained model is demonstrated by measurement and simulation of two methods of measuring upward current gain.

关键词： Electrical resistance measurement Current measurement Gain measurement Equivalent circuits Diodes density estimation robust algorithm Logic gates Conductivity Current supplies Voltage

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RESTORING CROPLAND PRODUCTIVITY AND PROFITABILITY IN NORTHERN ETHIOPIAN DRYLANDS AFTER NINE YEARS OF RESOURCE-CONSERVING AGRICULTURE

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EXPERIMENTAL AGRICULTURE 2016年第2期52卷 165-187页

作者： Araya, Tesfay Nyssen, Jan Govaerts, Bram Baudron, Frederic Carpentier, Louise Bauer, Hans Lanckriet, Sil Deckers, Jozef Cornelis, Wim M. Univ Ft Hare Dept Agron PBX1314 ZA-5700 Alice South Africa Mekelle Univ Dept Crop & Hort Sci POB 231 Mekelle Ethiopia Univ Ghent Dept Geog Krijgslaan 281 S8 B-9000 Ghent Belgium CIMMYT Int Maize & Wheat Improvement Ctr AP 6-641 Mexico City 06600 DF Mexico CIMMYT Int Maize & Wheat Improvement Ctr POB 5689 Addis Ababa Ethiopia Univ Ghent Dept Soil Management Coupure Links 653 B-9000 Ghent Belgium Katholieke Univ Leuven Dept Earth & Environm Sci Celestijnenlaan 200E B-3001 Heverlee Belgium

Long-term in situ soil and water conservation experiments are rare in sub-Saharan Africa, particularly in Eastern Africa. A long-term experiment was conducted (2005-2013) on a Vertisol to quantify the impacts of resource-conserving agriculture (RCA) on runoff, soil loss, soil fertility and crop productivity and economic profitability in northern Ethiopia. Two RCA practices were developed from traditional furrow tillage practices: (i) derdero+ (DER+) and terwah+ (TER+). DER+ is a furrow and permanent raised bed planting system, tilled once at planting time by refreshing the furrow and 30% of crop residue is retained. TER+ is ploughed once at planting, furrows are made at 1.5 m intervals and 30% crop residue is retained. The third treatment was a conventional tillage (CT) with a minimum of three tillage operations and complete removal of crop residues. Wheat, teff, barley and grass pea crops were grown in rotation. Runoff, and soil and nutrient loss were measured in plastic sheet-lined collector trenches. Significantly different (P < 0.05) runoff coefficients (%) and soil losses (t ha(-1)) averaged over 9 yrs were 14 and 3, 22 and 11 and 30 and 17 for DER+, TER+ and CT, respectively. Significant improvements in crop yield and gross margin were observed after a period of three years of cropping This study demonstrated that RCA systems in semi-arid agro-ecosystems constitute a field rainwater conservation and soil fertility improvement strategy that enhances crop productivity and economic profitability. Adoption of RCA systems (DER+ and TER+) in the study area requires further work to improve smallholder farmers' awareness on benefits, to guarantee high standards during implementation and to design appropriate weed management strategies.

关键词： TECR gene nutrient loss furrow density estimation robust algorithm Root Cause Analysis planting time crop residues Runoff coefficient

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Frequency modulation

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PROCEEDINGS OF THE INSTITUTE OF RADIO ENGINEERS 1930年第7期18卷 1194-1205页

作者： Van der pol, B Philips Incandescent Lamp Works Phys Lab Eindhoven HOLLAND

The differential equation of a frequency modulated transmitter is considered and the expression of the current as a function of time is derived. Frequency analysis of this function is made for two specific cases, (A) sinusoidal frequency modulation (telephony) and (B), right-angle frequency modulation (telegraphy with "marking" and "spacing" wave). The distribution and amplitudes of the frequencies present are seen to depend upon the value of an absolute parameter, the "frequency modulation index," equal to the ratio of the maximum frequency deviation to the imposed modulating frequency. The overall width of the band occupied is found to be approximately double the highest of these two frequencies. In the case of high-speed frequency modulated telegraphy, however, side frequencies of noticeable amplitude may occur outside this band. Charts are included showing the derived frequency spectra.

关键词： Frequency modulation Differential equations Telephony Telegraphy Circuits Amplitude modulation Inductance density estimation robust algorithm Laboratories Lamps

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