Showing papers by "Hanyang University published in 1990"
TL;DR: This article found that country of origin had a greater influence on product evaluations but affected the interpretation of attribute descriptions when presented in the same experimental session as the country-of-origin and intrinsic attribute information.
Abstract: Concepts related to country of origin can affect interpretation of information about specific product attributes However, these effects are likely to be pronounced only when country of origin is conveyed some time before attribute descriptions, allowing a separate concept of the product to be formed on the basis of it When country of origin and intrinsic attribute information were presented in the same experimental session, subjects perceived country of origin as simply another product attribute When presented the day before, however, country of origin not only had a greater influence on product evaluations but affected the interpretation of attribute descriptions
285 citations
TL;DR: In this article, three new process selection rules which can be applied to the FMS with limited local buffers and can flexibly cope with the change of system configuration {machine breakdown, etc.) are developed.
Abstract: SUMMARY This paper is concerned with the operational control problems in Flexible Manufacturing Systems (FMS) with limited local buffers. Three new process selection rules which can be applied to the FMS with limited local buffers and can flexibly cope with the change of system configuration {machine breakdown, etc.) are developed. In addition, AGV dispatching and AGC route selection rules are also developed for the simultaneous scheduling of jobs and material handling devices. The three new process selection rules (ARD, ARP and ARPD) are then compared with two existing rules (NAR and WINQ) by simulation experiments. The simulation experiments include the six operational control sub-problems for jobs and AG Vs. The multi-criteria performance measures considered simultaneously are makespan, mean flowtime, mean tardiness, maximum tardiness, and system utilization. The simulation results indicate that ARD gives the best results in four performance measures except for system utilization. Secondly, ARD, ARPD a...
73 citations
TL;DR: It is suggested that Rv and Ad40/41 in stools be accepted critically as an important cause of diarrhea among young children in Korea.
Abstract: To examine the role of rotavirus (Rv) and adenovirus types 40 and 41 (Ad40/41) in Korean children with acute gastroenteritis, we evaluated 345 children with acute gastroenteritis and 90 children without acute gastroenteritis in Seoul, Korea, during a 29-month period. Stools were tested for group A Rv antigen and for Ad40/41 by using monoclonal antibody (MAb)-based assays. Rv was found in 68% of the ill children and 19% of the controls (P less than 0.001), whereas Ad40/41 was detected in 9% of the ill children and 2% of the controls (P less than 0.05). Also, 6% of the ill children and 0.01% of the controls excreted Rv and Ad40/41 simultaneously. Among the ill children, 96% of children with Rv and 94% of those with Ad40/41 were younger than 24 months. Although a peak of Rv infection was detected in early winter in both years of the study, there was no apparent seasonal trend with Ad40/41. Diarrhea with more than 10 stools per day, vomiting, or fever was most strongly associated with Rv shedding, whereas the first two manifestations were associated with coinfection of Rv and Ad40/41. To investigate the genetic and serotypic diversity of Rv strains, we tested 195 and 144 fecal Rv specimens isolated from the gastroenteritis cases, respectively, by polyacrylamide gel electrophoresis of the segmented RNA genome and by an enzyme-linked immunosorbent assay with serotype-specific MAbs. Of the 195 specimens, 154 yielded RNA patterns characteristic of group A Rv: 18% had short electrophoretic migration patterns, 81% had long patterns, and 1% had a mixture of short and long patterns. Of the 144 specimens, serotype specificity was determined in 51%: 89% were serotype 1, 10% were serotype 2, and 1% were serotype 3. Analysis of the specimens for which electropherotypes and serotypes were available indicated that a given RNA pattern corresponded to a particular serotype, except in one strain that showed short patterns but serotype 1. We suggest that Rv and Ad40/41 in stools be accepted critically as an important cause of diarrhea among young children in Korea.
66 citations
TL;DR: A brief review of the literature concerning cestode infections in Korea finds that H. nana infection is relatively rare, showing 0.22% egg positive rate in a nationwide survey in 1986, and cysticercosis by T. solium often reveals serious clinical manifestations.
Abstract: Epidemiological surveys concerning cestodes of medical importance in Korea have been sporadically reported by many workers. Among various parasitic infections, cestode infections occur less frequently than other helminthiases, but they often cause serious clinical complications. Cestodes reported so far in Korea belong to the Order Pseudophyllidea or Cyclophyllidea (Subclass Cestoda), i.e., Diphyllobothrium latum, D. yonagoense, Spirometra erinacei, sparganum, Hymenolepis diminuta, H. nana, Mesocestoides lineatus, Taenia saginata, T. solium, metacestode of T. solium (cysticercus), and Echinococcus granulosus. The present paper is a brief review of the literature concerning these cestode infections in Korea. Taeniases by T. saginata or T. solium are prevalent cestode infections in Korea, and cysticercosis by T. solium often reveals serious clinical manifestations. H. nana infection is relatively rare, showing 0.22% egg positive rate in a nationwide survey in 1986. Sparganosis by the plerocercoid larva of Spirometra is not an uncommon cestode infection in man, and 16 kinds of animal hosts including the snakes and frogs have been reported. D. latum infection has been an uncommon intestinal parasitosis, but it tends to increase nowadays. Most of human hydatidosis cases have been recognized as imported ones from outside Korea, but one case was proven indigenous. Other 4 kinds of cestodiases are extremely rare in Korea and only a few cases have been recorded.
66 citations
TL;DR: The first report of an oncocytic glomus tumor arising from the trachea is reported, in a 47-year-old woman, who experienced intermittent cough and hemoptysis for about three years.
41 citations
TL;DR: In this paper, the rates of densification and the mechanical properties of pure ZrO{sub 2}O(sub 3) and Zr O{sub 3}-toughened ZTA (ZTA hot isostatically pressed at 1600{degrees}C and 100 MPa, respectively, were investigated as a function of the temperatures and time schedules used for HIP.
Abstract: The rates of densification and the mechanical properties of pure Al{sub 2}O{sub 3} and ZrO{sub 2}-toughened Al{sub 2}O{sub 3} (ZTA) have been investigated as a function of the temperatures and time schedules used for hot isostatic pressing (HIP) as a postsintering heat treatment for samples which had already been pressureless sintered in air at 1460{degrees}C for 45 min. ZTA hot isostatically pressed at 1400{degrees}C had a finer grain size and a narrower grain size distribution than ZTA hot isostatically pressed at 1600{degrees}C. At both HIP conditions, the density which could be obtained was almost the maximum theoretical density. The amount of grinding-induced and fracture-induced monoclinic ZrO{sub 2} formed as a result of the tetragonal {r arrow} monoclinic martensitic transformation in ZTA was higher in the samples hot isostatically pressed at 1400{degrees}C. ZTA hot isostatically pressed at 1600{degrees}C and 100 MPa had fewer flaws and higher strengths than ZTA hot isostatically pressed at 1400{degrees}C for the same time, with a gradual improvement in mechanical properties with increasing HIP time at each of these two temperatures.
29 citations
TL;DR: The distributions of trace metals in the Geum Estuary of western Korea were studied with regard to changes in other estuarine chemical parameters as discussed by the authors, including dissolved oxygen, pH, and alkalinity increased with increasing salinity.
Abstract: The distributions of trace metals in the Geum Estuary of western Korea were studied with regard to changes in other estuarine chemical parameters. Dissolved oxygen, pH, and alkalinity increased with increasing salinity. Dissolved aluminum concentrations increased at low salinities and were perhaps influenced by the solubility of particulate aluminosilicate phases. Iron, managanese, cobalt, and zinc are removed from solution in the low salinity end of the estuary. Cobalt and nickel have mid-estuary concentration maxima that may be due to an anthropogenic source. Cadmium, copper, lead, and zinc concentrations also increased in the estuary, possibly as the result of remobilization in the sediments. Cadmium increases are also linked to remineralization from tidal flat sediments in the outer estuary. The source of an increase in dissolved lead at low salinity is unclear, but may be due to release from particles.
27 citations
TL;DR: Child battering was more serious in families in the lower social strata, with poor living conditions, in broken families such as those with stepparents or absent mothers, and where parents were unskilled workers or unemployed.
26 citations
TL;DR: Cardiac arrhythmias seem to originate from a combination of the ion channel properties, intercellular conduction properties, and geometry of the heart, and close similarities between chaotic rhythms observed in single cardiac cells and clinically observed devil's staircase suggest that some arrh rhythmias may be described by the nonlinear nature of membrane excitability of single cell.
Abstract: Ordinarily, the heart beats with a regular rhythm. Under certain circumstances, however, the heart discharges abnormal rhythms and/or ceases beating entirely. Since the heart consists of a network of excitable cells, the heart rhythm is controlled by the ionic channel activity in the constituent cells as well as the global nature of a network system. Cardiac arrhythmias seem to originate from a combination of the ion channel properties, intercellular conduction properties, and geometry of the heart. Nevertheless, close similarities between chaotic rhythms observed in single cardiac cells'-3 and clinically observed devil's staircase4 suggest that some arrhythmias may be described by the nonlinear nature of membrane excitability of single cell^.^-'^ This nonlinear nature is due to the conductance of the ionic channel, which depends on membrane potential In the heart cells, voltage-gated Ca2+ channels are important for the genesis of the action potentials.'' Several types of CaZ+ channels have been identified by their electrophysiological properties in the heart cells\"~\" and in other excitable The so-called \"slow\" Ca2+ channels are most often observed in the excitable cells.22 Inactivation of this channel is commonly believed to be the key to the electrical activity in heart cells, as well as nerve and endocrine cells.22 During 150-ms depolarization potentials, this channel inactivates only partially in the presence of Ca2+ ions and inactivates very little in the presence of Ba2+ ions.\"~'3~'2~'9~20~23~24 If the duration of the step potential is increased to several seconds, the slow Ca2+ channel inactivates almost ~ o m p l e t e l y . ' ~ , ~ ~ This slow inactivation depends on membrane In some cardiac and neuronal cells, the fast inactivating inward current is caused either by a N a + current or a Ca2' current through other types of Ca2+ channels (e.g., Tor N-types). inactivation of a Na' current is partly responsible for the refractory
26 citations
TL;DR: In this paper, the authors investigate the effect of small sample bias in regression on the lagged value of the dependent variable and show that a number of the characteristica of the historical results can be replicated simply by the combined effects of the two small sample biases.
Abstract: Recent research suggests that stock returns are predictable from fundamentals such as dividend yield, and that the degree of predictability rises with the length of the horizon over which return is measured. This paper investigates the magnitude of two sources of small simple bias in these results. First, it is a standard result in econometrics that regression on the lagged value of the dependent variable is biased in finite samples. Since a fundamental such as the price/dividend ratio is a statistical proxy for lagged price, predictive regressions are potentially subject to a corresponding small sample bias. This may create the illusion that one can buy low and sell high in the sample even if the relationship is useless for forecasting. Second, multiperiod returns are positively autocorrelated by construction, raising the possibility of spurious regression. Standard errors which are computed from the asymptotic formula may not be large enough in small samples. A set of Monte Carlo experiments are presented in which data are generated by a version of the present value model in which the discount rate is constant so returns are not in fact predictable. We show that a number of the characteristica of the historical results can be replicated simply by the combined effects of the two small sample biases.
16 citations
TL;DR: In this paper, a total of 1,100 American hotel sales and marketing professionals were surveyed to examine how these professionals became committed to their organization and found that organizational commitment was mainly a function of work-related characteristics (Job satisfaction and professional commitment).
Abstract: A total of 1,100 American hotel sales and marketing professionals were surveyed to examine how these professionals became committed to their organization. It was found that organizational commitment was mainly a function of work-related characteristics (Job satisfaction and professional commitment). Some theoretical and practical implications are also discussed.
TL;DR: The superplastic properties of this material were evaluated in the temperature range of 400 °C to 545 °C over the strain-rate range of 2.8 X 10-4 to 2.2 s-1 as mentioned in this paper.
Abstract: Thermomechanical processes were developed which give fine grain sizes of 6 and 8 μm in the 7475 Al alloy. Superplastic properties of this material were evaluated in the temperature range of 400 °C to 545 °C over the strain-rate range of 2.8 x 10-4 to 2.8 X 10-2 s-1. The maximum ductility exhibited by the alloy was approximately 2000 pct, and optimum superplasticity was achieved at a strain rate of 2.8 X 10-3 s-1 which is higher by an order of magnitude than other 7475 Al alloys. This result is attributed to the presence of fine dispersoids which maintain the fine grain size at high homologous temperatures. The flow stress and strain-rate sensitivity strongly depend on the grain size. The superplastic 7475 Al alloy has strain-rate sensitivities of 0.67 (6 μm) and 0.5 (13 μm) and an activation energy which is similar to the one for grain boundary diffusion of aluminum. Microstructural investigation after superplastic tests revealed zones free of dispersoid particles at grain boundaries primarily normal to the tensile direction. These dispersoidfree zones (DFZs) appear even after 100 pct elongation and are occasionally as large as 5 μm across. This result demonstrates the importance of diffusional flow in superplastic deformation of the fine-grained 7475 Al alloy especially at low elongations.
TL;DR: Grain boundary self-and 57Co impurity diffusion was measured in sintered tungsten on a large temperature interval in this paper, where the results were discussed in terms of the grain boundary phase transition model of Militzer and Wieting.
Abstract: Grain boundary self- and 57Co impurity diffusion were measured in sintered tungsten on a large temperature interval. Additionally the diffusion of 185W was investigated in Ni-doped tungsten grain boundaries in the context of the activated sintering process. In al1 three cases an unusual discontinuity was obseved in the Arrhenius plot occurring around 1370 K with quite different magnitudes for self and impurity diffusion. The results were discussed in terms of the grain boundary phase transition model of Militzer and Wieting.
TL;DR: In this paper, the separation of water-ethanol binary mixture through polyacrylonitrile (PAN) and its modified membranes was studied using pervaparation processes.
Abstract: In the present work the separation of water-ethanol binary mixture through polyacrylonitrile (PAN) and its modified membranes was studied using pervaparation processes. PAN was chosen as a base polymer because of its high affinity with water. As a result, homogeneous PAN membrane has an extremely high selectivity toward water and has low fiuxes in pervaparation. Membrane morphology of PAN influences to a great extent on the membrane performance when separating the aqueous ethanol solution. This study investigates the way to control the membrane morphology and the membrane performance. The key factors affecting the membrane morphology include the membrane casting variables such as concentration of casting solution, solvent evaporation temperature, solvent evaporation pressure, the membrane thickness and the presence of nonsolvents in casting solution. Membranes we investigated are homogeneous, blend-type and copolymer-type PAN membranes. A statistical method was adopted in the experiment. As a consequence it was possible to effectively predict fiuxes and separafion factors using these membranes to dehydrate aqueous ethanol solution.
TL;DR: A nation-wide collection of biopsy-confirmed and surgically removed thyroid lesions from 30 pathology laboratories of university and general hospitals was made over a 3-year-period from 1986 to 1988, finding thyroid diseases were common at the 3rd to 6th decades with peak incidence at the 4th decade.
Abstract: In order to determine the incidence and to understand recent trend of thyroid neoplasm and other thyroid diseases among Korean, a nation-wide collection of biopsy-confirmed and surgically removed thyroid lesions from 30 pathology laboratories of university and general hospitals was made over a 3-year-period from 1986 to 1988. These tumors and tumor-like lesions of the thyroid were classified according to the WHO classification. Results of this study were compared with those of the previous in Korea and other countries. Among the 7758 collected cases from 7449 patients, adenomatous goiter was the most common, comprising 2681 cases (34.6%), followed by follicular adenoma, 1868 cases (24.1%) and papillary carcinoma, 1474 cases (19%). Neoplastic condition comprised 48.8% (3786 cases). Of malignant tumors, papillary carcinoma was the most frequent accounting for 79.8%. The female to male ratio was 7.5:1 with female predominance. This female predominance was noted in all but two thyroid diseases. Medullary carcinoma showed equal distribution in both sexes, and two cases of malignant lymphoma developed in males. Thyroid diseases were common at the 3rd to 6th decades with peak incidence at the 4th decade. The right lobe of the thyroid was more frequently involved than the left lobe (1.6:1). The diagnoses were made largely on the surgically excised specimen (85.3%). Multiplicity of the lesions revealed single lesion in 64%, multiple and diffuse lesion in 36% of cases investigated. Average size of the lesion was in the range of 1-5 cm in diameter (62%).
TL;DR: The method, which employs the model algorithmic control concept in the iteration sequence, is shown to be convergent for linear time-varying systems and applicable for continuous-path control of a robot manipulator.
Abstract: A new type of an iterative learning control method is proposed for dynamic systems with uncertain parameters. The method, which employs the model algorithmic control concept in the iteration sequence, is shown to be convergent for linear time-varying systems. Then the method is shown to be applicable for continuous-path control of a robot manipulator.
TL;DR: A rare example of multiple fibrous hamartoma of infancy is described and it will be further elucidated whether multiple forms and early recurrence are related or not as cases accumulate.
Abstract: Fibrous hamartoma of infancy is an uncommon benign fibrous proliferation, usually presenting as a solitary nodule. A rare example of multiple fibrous hamartoma of infancy is described. Two masses which developed in the upper arm of a 10-month-old boy were successfully excised, and one month later three small nodules 2 cm below the previous operation field appeared. It will be further elucidated whether multiple forms and early recurrence are related or not as cases accumulate.
TL;DR: In this article, the authors carried out metallurgical investigations on the relation between wear rate and plastic flow phenomena in the subsurface zone of high carbon Cr-Ti alloy steel and commercial rail steel under rolling contact conditions.
TL;DR: In this article, a cross-linked blendmer (XSC-PVA) was obtained by mixing two aqueous solutions of the anionic charged PVA, whose degrees of substitution were 25%, respectively, using glutaraldehyde as the cross-linking agent.
Abstract: Based on the anionic groups which appear in heparin, sulfonated poly(vinyl alcohol) (S-PVA), and carboxymethylated poly(vinyl alcohol) (C-PVA) were synthesized. Cross-linked blendmer (XSC-PVA)s were obtained by mixing two aqueous solutions of the anionic charged PVA, whose degrees of substitution were 25%, respectively, using glutaraldehyde as the cross-linking agent. These XSC-PVA membranes were prepared under various conditions in order to determine a suitable mixing ratio of S-PVA to C-PVA and concentration of cross-linking agent. Effect of amount of cross-linker on permeability and mechanical property of the membranes was also examined.
TL;DR: In this paper, the electrical and physical properties of the CuS and CdS-introduced polyacrylonitrile (PAN) films were studied and temperature dependence of surface conductivity for CuS-PAN composite film was investigated.
Abstract: Electrical and physical properties of the CuS- and CdS-introduced polyacrylonitrile (PAN) films were studied. Electrically conducting PAN film was prepared by introducing CuS and CdS by the organosol method. Electrical surface conductivity of CuS- and CdS—PAN composite film prepared by the organosol method was 10−1 and 10−5 S/cm, respectively. Temperature dependence of surface conductivity for CuS—PAN composite film was investigated. The IV characteristics and time dependence of conductivity of samples were observed. The conduction mechanism of CuS– and CdS–PAN composite film was mainly electronic. Electrical properties of the CuS– and CdS—PAN composite film were mainly governed by the CuS and CdS crvstal formed in the PAN film. Temperature dependence of surface conductivity of the heat-treated CuS—PAN composite film was also investigated. Results show that the electrical properties of the sample were varied slightly according to annealing temperature. Tensile strength and modulus of CuS– and CdS—PAN composite film were slightly decreased than original PAN film, but this decrease was not prevented utilization in electronic devices.
TL;DR: In this article, the incorporation of carboxylic acid groups into the glassy polyacrylonitrile membrane made it possible to selectively separate water from aqueous ethanol solution by pervaporation.
Abstract: Pervaporation performance of poly(acrylonitrile-co-acrylic acid) membranes was examined at several feed ethanol concentrations and temperatures. The incorporation of carboxylic acid groups into the glassy polyacrylonitrile membrane made it possible to selectively separate water from aqueous ethanol solution by pervaporation. Carboxylic groups play a role as carriers for water. Concentration dependent diffusion of water through the membranes was assumed and a new permeation equation is proposed and discussed.
TL;DR: In this article, three derivatives of chitosan, namely, thiosemicarbazide, phosphoric acid and amidoxime derivatives, were synthesized and their ability for metal ion adsorptions was discussed.
Abstract: Thiosemicarbazide, phosphoric acid and amidoxime derivatives of chitosan were synthesized and their ability for metal ion adsorptions was discussed. Thiosemicarbazide derivative, synthesized by treating chlorodeoxychitosan with ammonium thiocyanate followed by treatment with hydrazine, was considered to have cross-linked network structure. Phosphoric acid derivative containing both N-phosphonic acid and phosphoric acid groups was synthesized by cyanoethylation of chitosan using acrylonitrile, followed by treatment with hydroxylamine. These derivatives were found to adsorb effectively infinitesimal concentration (ppb order) of uranyl ion in seawater. Stability constants of some metal ion chitosan chelates were determined. To improve the selectivity in the adsorption of metal ions, a novel method utilizing metal ion as a template was adopted, and the results are discussed.
TL;DR: It is assumed that P. westermani infection can induce the non-specific activation of peritoneal macrophage, and serum antibodies including IgE antibody might enhance the cytotoxicity by macrophages.
Abstract: Paragonimus westermani is a tissue migrating parasite in the early stage until arriving at lung, and most of the parasites spend their life spans there. Considerable immune responses including activation of macrophages are taken place during the residence of parasites in the host. However, concerning the immunologic defense mechanisms of the host against this parasite, only a few document is available so far. In this study, the cytotoxic effect of peritoneal macrophages under the presence of antibody and/or complement against metacercariae of P. westermani was investigated in vitro. Metacercariae were collected from the crayfish, Cambaroides similis and hatched out in Tyrode solution (pH 7.4). Plastic adherent cells from normal or infected rat (Wistar) peritoneal exudates were used as experimental macrophages. Polyclonal antibodies were obtained from infected rats and a cat. Cat IgG was fractioned with ion exchange chromatography. Fresh rabbit complement was used according to experimental scheme. Various combinations of peritoneal macrophages, normal or infected rat serum, complement and cat IgG were incubated at 36 degrees C in 5% CO2 incubator for 6, 14, 24 and 48 hours. The results obtained were as follows: 1. P. westermani infection activated peritoneal macrophages non-specifically and this activation induced increases of cell adherence and cytotoxicity on metacercariae. 2. In the presence of infected rat serum the antibody-dependent cell-mediated cytotoxicity of peritoneal macrophages on metacercariae was significantly increased and showed a peak at 6-hour incubation. But the cytotoxic effect was markedly reduced after inactivation of complement and heat-labile IgE antibody by the heating of infected serum at 56 degrees C for 30 minutes. 3. The highest cytotoxic effect (100%) of concomitant incubation with IgG and complement showed 24 hours after incubation, although cell adherence was relatively low at 6-hour incubation and 0% at 24-hour incubation. 4. Coordinative functions of complement with serum and IgG were effective in cell adherence and in cytotoxicity, but it is not clear the independent role of complement on the macrophage-mediated cytotoxicity in this study. With these results it is assumed that P. westermani infection can induce the non-specific activation of peritoneal macrophages, and serum antibodies including IgE antibody might enhance the cytotoxicity by macrophages.
01 Nov 1990
TL;DR: In this article, the 2nd order maximum entropy method (MEM) was used to estimate the mean frequency of the myoelectric (ME) signal during muscle contraction.
Abstract: During a sustained muscle contraction, it is observed that the power spectrum of the myoelectric (ME) signal shifts toward lower frequencies. The mean frequency can be a parameter to monitor the local muscle fatigue. We found that the 2nd order Maximum Entropy Method (MEM) approach provides more accurate and noise-immune mean frequency estimation than the FFT method. The advantage of the 2nd order MEM is simple and fast, and it yields unbiased and consistent estimation of mean frequency of ME signal.
TL;DR: Cross-linked blendmers of the polyvinyl alcohol (PVA) with substituted anion have been prepared by measuring tensile strength and elongation under dry and wet condition, and studied by in-vitro blood tests as discussed by the authors.
Abstract: Cross-linked blendmers of the poly(vinyl alcohol) (PVA) with substituted anion have been prepared Possibilities of the samples for the usage as biomaterial were estimated by measuring the tensile strength and elongation under dry and wet condition, and studied by in-vitro blood tests And the contact angle of the samples were also investigated in order to examine the surface properties The most improved anticoagulation activity was observed in XSC-3 which is a blendmer of 60 wt% of the sulfonated PVA and 40 wt% of the carboxymethylated PVA
TL;DR: In this paper, the superconducting YBa2Cu3O7-x (YBCO) thin films on MgO(100) substrates were prepared by a reactive evaporation method.
Abstract: The superconducting YBa2Cu3O7-x (YBCO) thin films on MgO(100) substrates were prepared by a reactive evaporation method. Superconducting transition temperature and crystal quality were examined as a function of the substrate temperature (Ts) and the oxygen partial pressure (PO2 ). The as-grown thin films at the substrate temperature of 620°C exhibited a zero resistance temperature (Tczero ) of 83 K with the onset (Tconset ) temperature of 88 K under the PO2 of 2×10-3 Torr. The lattice parameter c was about 11.74 A for the as-grown film with Tczero of 80 K and was shortened to about 11.70 A by the post-annealing at 900°C for 10 min in O2 flow, although Tczero was not changed. This phenomena may be ascribed to the deficiency of oxygen in the CuO2 plane of the YBCO layered perovskite structure.
TL;DR: In this paper, an off-line geometric adaptive control (GAC) scheme is proposed to compensate for machining straightness errors due to the machine tool's inaccuracy and those arising as a result of the metal cutting process during the finish peripheral end milling process.
Abstract: An off-line Geometric Adaptive Control (GAC) scheme is proposed to compensate for machining straightness errors due to the machine tool's inaccuracy and those arising as a result of the metal cutting process during the finish peripheral end milling process. In the milling process, the workpiece travels along the guideway while the spindle system remains fixed. The scheme is based on the exponential smoothing of post-process measurements of relative machining errors due to the tool and bed deflections. Without a priori knowledge of the variations of the cutting parameters, the time-varying parameters are estimated by an Exponentially Weighted Recursive Least Squares (EWRLS) method. This method is able to incorporate a straightedge which is not necessarily accurate to identify the guideway errors. To reduce the drift of the cutting parameters, a single parameter adaptation method is introduced. Experimental results show that the location error is controlled within the range of the fixing error of the milling bed on the guideway. Further, the waviness error is reduced to less than 10 μm in the machining of a 508-mm long prismatic workpiece regardless of the machining conditions.
TL;DR: It is indicated that mouse peritoneal macrophages are spontaneously cytotoxic for T. vaginalis and lymphokine increases the cytotoxicity by activating macrophage activation for the killing.
Abstract: This study was aimed to observe the direct and lymphokine-activated cell mediated cytotoxic effects against Trichomonas vaginalis by mouse peritoneal macrophages. Cytotoxicity was measured as release of 3H-thymidine from prelabeled protozoa, and tested in U-bottom microtiter plates. A 0.1 ml suspension of labeled protozoa (2 x 10(5)/ml) was placed in each well, followed by 0.1 ml of a suspension containing increasing numbers of peritoneal cells. After a 24 hr incubation at 37 degrees C, 0.1 ml of the supernatant was collected and counted in liquid scintillation counter. Mouse peritoneal macrophages had appreciable level of spontaneous cytotoxicity against T. vaginalis at the effector to target cell ratios from 5:1 to 50:1. Treatment of macrophages with lymphokine, produced by PHA-stimulated spleen cells, increased the cytotoxicity in comparison with resident macrophages against T. vaginalis. The degree of macrophage activation for the killing was not dependent upon the lymphokine concentration. Peritoneal cells adherent to plastic displayed significant levels of cytotoxicity against T. vaginalis. This study indicates that mouse peritoneal macrophages are spontaneously cytotoxic for T. vaginalis and lymphokine increases the cytotoxicity by activating macrophages to kill T. vaginalis.
TL;DR: It is assumed that ELISA is a reliable method for the diagnosis of T. vaginalis infection and simultaneous measurement of serum IgG and IgM with this technique is recommended.
Abstract: The direct wet mount examination of vaginal secretion, widely applied for the diagnosis of Trichomonas vaginalis infection in woman patients, is rapid and economical, however, the sensitivity of this technique is not so high. In this study enzyme-linked immunosorbent assay (ELISA) was employed for the detection of serum anti-T. vaginalis IgG and IgM antibodies from 30 vaginal trichomoniasis patients and 30 non-infected healthy persons. The results were as follows: 1. Serum ELISA-IgG value was 0.37 +/- 0.134 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.21 +/- 0.054 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgG antibody were 70.0% and 96.7%, respectively. 2. Serum ELISA-IgM value was 0.33 +/- 0.177 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.11 +/- 0.051 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgM antibody were 70.0% and 96.7%, respectively. 3. The ELISA-IgG values showed a significant correlation with ELISA-IgM values (r = 0.77, p less than 0.005). With above results, it is assumed that ELISA is a reliable method for the diagnosis of T. vaginalis infection and simultaneous measurement of serum IgG and IgM with this technique is recommended.