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1.
Vegetable-based polyurethane (PU) was prepared in the thin film form by spin coating. This polymer is synthesised from castor oil, which can be extracted from the seeds of a native plant in Brazil called mamona. This polymer is biocompatible and is being used as material for artificial bone. The PU was characterised by dielectric spectroscopy in a wide range of frequency (10–5 Hz to 105 Hz) and by thermally stimulated discharge current (TSDC) measurements. The glass transition temperature (T g = 39°C) was determined and using the initial rise method the activation energy was found to be 1.58 eV.  相似文献   
2.
在滤波应用中,超低失真的表面贴装多层陶瓷电容(MLCC),已经成为模拟电路设计者在SMD塑料薄膜(薄膜片式)电容之外的另一种选择,它的体积更小、成本更低、也更为可靠。这些潜在的模拟电路应用实例包括:音响设备、无线设备、锁相环(PLL)和通信设备(如调制/解调器)等。这些新型电容的等效串连电阻(ESR)极低,因此非常适合于高效率的DC/DC变换器和高速微处理器应用。低失真电容的应用随着处理器速度的提高和工作电压的降低,噪声会给信号完整性带来严重的影响,除非能通过过滤或解耦的办法将其去除。在声频、射频、PLL和通信电路中,跟踪误差…  相似文献   
3.
OBJECTIVE: To better understand the immunoglobulin variable (V) region repertoire of rheumatoid factors (RF). METHODS: We characterized the heavy (H) and light (L) chain gene segments utilized in a monospecific IgG RF secreting hybridoma (AEE111F) which were derived from a patient with rheumatoid arthritis (RA). The hybridoma was established by fusion of a mouse myeloma cell line with bone marrow derived mononuclear cells from a patient with RA. First strand complementary DNA (cDNA) was generated and used for a polymerase chain reaction amplification of the H and L chain V domains. The amplified V domains were sequenced and compared with an extensive database of germline and cDNA V gene segments. RESULTS: The VH sequence was found to be 96% homologous to a previously described fetal VH3 cDNA (60P2). The VL sequence was also highly homologous to the previously described V lambda II gene (96%) derived from a patient with systemic lupus erythematosus which correlated with an 8.12 idiotype (Id), and to an antibacterial antibody against the Haemophilus influenzae type b capsular polysaccharide (94.7%). CONCLUSION: The overlap among this RF VL gene and the 2 reported V lambda sequences of antibodies that expressed anti-DNA related Id and an environmental pathogen specificity suggests that a part of the IgG RF isolated from patients with RA may thus be derived from the physiological natural antibody repertoire during an abnormal immune response and then develop high affinity, monospecific RF by the selection of an antigen driven mechanism.  相似文献   
4.
Full-wave solutions to the problem of radiation by open-ended rectangular waveguides (OEG) are presented. The radiation problem is formulated in terms of an electric field integral equation (EFIE). The EFIE is solved using the method of moments for three OEG antennas covering the frequency range from 200 to 750 MHz. Results for the near-zone gains as a function of both frequency and distance from the OEG aperture are presented. Estimates for uncertainties in the calculated gain are also given  相似文献   
5.
We propose a micro-benchmark for XML data management to aid engineers in designing improved XML processing engines. This benchmark is inherently different from application-level benchmarks, which are designed to help users choose between alternative products. We primarily attempt to capture the rich variety of data structures and distributions possible in XML, and to isolate their effects, without imitating any particular application. The benchmark specifies a single data set against which carefully specified queries can be used to evaluate system performance for XML data with various characteristics.  相似文献   
6.
The 3107 cm−1 hydrogen related local mode was produced in HPHT grown diamonds after annealing at temperatures above 2100°C. A correlation was found between the intensity of the peak and the concentration of nitrogen at different locations of the same specimen. The peak position did not shift in 15N doped samples.  相似文献   
7.
Polytetrafluoroethylene (PTFE) microstructures’ processing characteristics using X-ray photo dcomposition and desorption are studied in the highest energy region (2 keV to >12 keV). While the exposed surface states are seen melting and boiling from the remaining bubble structure of the irradiated surface, basic photochemistry of PTFE is also same as previous reports and high-aspect ratio structures are successfully formed. We developed new Ni stencil electroformed stencil masks and successfully fabricated first and practical example of PTFE micro fluidic parts. The characteristics of fabricated micro fluidic parts, a PTFE fluid filter for vertical fluid flow operation which works as passive valve, agreed with the calculated results. This suggests that the accuracy of patterning is adequate to apply this technique to fabricate microfluidic parts and other various microparts.  相似文献   
8.
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis.  相似文献   
9.
Free and open source software (FOSS) plays an important role in source code reuse practice. They usually come with one or more software licenses written in the header part of source files, stating the requirements and conditions which should be followed when been reused. Removing or modifying the license statement by re-distributors will result in the inconsistency of license with its ancestor, and may potentially cause license infringement. In this paper, we describe and categorize different types of license inconsistencies and propose a method to detect them. Then we applied this method to Debian 7.5 and a collection of 10,514 Java projects on GitHub and present the license inconsistency cases found in these systems. With a manual analysis, we summarized various reasons behind these license inconsistency cases, some of which imply potential license infringement and require attention from the developers. This analysis also exposes the difficulty to discover license infringements, highlighting the usefulness of finding and maintaining source code provenance.  相似文献   
10.
Identifying the extent to which the appearance of a humanoid robot affects human behavior toward it is important. We compared participant impressions of and behaviors toward two real humanoid robots in simple human-robot interactions. These two robots, which have different appearances but are controlled to perform the same recorded utterances and motions, are adjusted by a motion-capturing system. We conducted an experiment with 48 human participants who individually interacted with the two robots and also with a human for reference. The results revealed that different appearances did not affect participant verbal behaviors, but they did affect such nonverbal behaviors as distance and delay of response. These differences are explained by two factors: impressions and attributions.  相似文献   
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