• Title/Summary/Keyword: Small Samples

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Effect of Chromium Chloride on the Mechanical and Dielectric Properties of EPDM Rubber

  • Salem, M.A.;Khaled, M.A.;Hussein, A.M.;Elway, E.
    • Macromolecular Research
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    • v.11 no.4
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    • pp.256-259
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    • 2003
  • Measurements of Young's modulus, dielectric loss and a.c. conductivity have been carried out on EPDM rubber samples loaded with different concentrations of $CrCl_3$ (0,2,4 and 6 phr). The values of Young's modulus was found to be linearly dependent on the $CrCl_3$ content. Variation of the dielectric loss with temperature showed that $CrCl_3$ may act as plasticizer. However, at higher frequencies the dielectric loss was found to be independent of frequency and the rubber samples may behave as non-polar dielectric. Investigations of the a.c conductivity suggested that the conduction in these rubber samples can be described by small polaron tunneling. In addition, conductivity was found to increase with $CrCl_3$ content.

Preparation and Properties of Co$_{9-x}M_xS_8$(M = Ni, Rh, Ru, and Fe)

  • Kim, Kwan
    • Bulletin of the Korean Chemical Society
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    • v.7 no.2
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    • pp.102-105
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    • 1986
  • Samples with the nominal composition of $Co_{9-x}M_xS_8$(M = Ni, Rh, Ru, and Fe) were prepared, and their magnetic properties were measured. X-ray diffraction analysis showed that small amount of the elements Ni, Rh, and Fe could be incorporated into $Co_9S_8$ forming a homogeneous ${\pi}$-phase, whereas the Ru-incorporated sample could not be prepared in a single phase. The lattice parameter was observed to increase as other elements were incorporated into $Co_9S_8$. Samples incorporated with the elements of Ni, Rh, and Ru showed Pauli-paramagnetism while the Fe-incorporated sample exhibited weak ferromagnetism. The values of magnetic susceptibility for the Ni, Rh, Ru-incorporated samples were nearly the same as that of pure $Co_9S_8$.

Integrating Spatial Proximity with Manifold Learning for Hyperspectral Data

  • Kim, Won-Kook;Crawford, Melba M.;Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.26 no.6
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    • pp.693-703
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    • 2010
  • High spectral resolution of hyperspectral data enables analysis of complex natural phenomena that is reflected on the data nonlinearly. Although many manifold learning methods have been developed for such problems, most methods do not consider the spatial correlation between samples that is inherent and useful in remote sensing data. We propose a manifold learning method which directly combines the spatial proximity and the spectral similarity through kernel PCA framework. A gain factor caused by spatial proximity is first modelled with a heat kernel, and is added to the original similarity computed from the spectral values of a pair of samples. Parameters are tuned with intelligent grid search (IGS) method for the derived manifold coordinates to achieve optimal classification accuracies. Of particular interest is its performance with small training size, because labelled samples are usually scarce due to its high acquisition cost. The proposed spatial kernel PCA (KPCA) is compared with PCA in terms of classification accuracy with the nearest-neighbourhood classification method.

Determination of MDMA and MDA in 44 hair samples during 2002 to 2003

  • Han, Eun-Young;Yang, Won-Kyung;Lee, Jae-Sin;Park, Yong-Hoon;Kim, Eun-Mi;Lim, Mi-Ae;Chung, Hee-Sun
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.112.1-112.1
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    • 2003
  • The qualitative and quantitative analysis of MDMA and MDA in hair samples by GC/MS were reported. Hairs were collected from subjects aged 22-37 years, who were suspected of abusing MDMA. After washing with methanol, hair samples were cut into small pieces, extracted with methanol containing 1 percent hydrochloric acid for 20th, and the solution was evaporated. MDMA or MDA in the extract were determined by GC/MS using selected ion monitoring after derivatization with trifluoroacetic anhydride. (omitted)

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Study on the Closure Time in Healthy Small-Breed Dogs by Platelet Function Analyzer-200

  • Kyoungyoun Lee;Yoonhee Kim;Ulsoo Choi
    • Journal of Veterinary Clinics
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    • v.40 no.5
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    • pp.330-335
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    • 2023
  • Platelet function evaluation by PFA-100 or -200 has been known to be objective and sensitive for assessing platelet function and dysfunction of Von Willebrand Factor in humans and dogs. However, using the C/EPI cartridge in dogs is controversial. This study aimed to establish a reference range for PFA closure time in healthy small breed dogs (body weight < 10 kg) and to evaluate the effectiveness of both C/ADP and C/EPI cartridges for these dogs. Citrated blood samples were collected from 50 clinically healthy small breed dogs that were admitted for presurgical procedures or health checkups, and closure times were measured using the PFA-200. Reference ranges were determined as 42-144 s (median 67 s, mean 71.2 s, SD ± 21.2 s, 95% RI 43-140 s) , for CT-C/ADP and 41-200 s (median 87, mean 91.2 s, SD ± 31.8 s, 95% RI 44-195 s) for CT-C/EPI. The present study demonstrated that the reference ranges for PFA closure times in small breed dogs are in line with existing reference ranges. The utilization of C/ADP cartridges is the preferred choice for evaluating platelet function in small breed dogs. However, due to variable responses of epinephrine to platelet aggregation in dogs, caution should be exercised when using C/EPI cartridges.

Mechanical Property and Crystallization of Glass by Femtosecond Laser Pulses (Femto Second Laser Pulse에 의한 유리의 결정화 및 기계적 특성)

  • Cha, Jae-Min;Moon, Pil-Yong;Kim, Dong-Hyun;Park, Sung-Je;Cho, Sung-Rak;Ryu, Bong-Ki
    • Journal of the Korean Ceramic Society
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    • v.42 no.6 s.277
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    • pp.377-383
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    • 2005
  • Generally, the strength achieved of glass-ceramics is higher as is the fracture toughness, as compared with the original glass. This improvement is due to the microstructure consisting of very small crystals. In this study, Ag-doped $45SiO_2-24CaO-24Na_2O-4P_2O_5$ glasses were irradiated to strengthen by the crystallization using Femto second laser Pulses. Through the UV/VIS spectroscope, XRD, Nano-indenter and SEM etc., heat-treated and irradiation of laser pulses without heat-treated samples were analyzed. Two kinds of samples, heat-treated and laser irradiated without heat-treated samples, showed the peaks in the same wavelength near 360 nm. Especially, samples irradiated by 140 mW laser with XYZ stage having at the rate of 100$\~$l000 $\mu$m/s had the largest absorption peak among them, and heat-treated samples was shown lower absorption range than over 90 mW laser irradiated samples. Moreover, samples irradiated by laser had higher values ($4.4\~4.56{\times}10^{-3}(Pa)$) of elastic modulus which related with strength of glass than values of heat-treated samples and these are 1.2$\~$1 .5 times higher values than them of mother glass.

High Feasibility of Liquid-Based Cytological Samples for Detection of EGFR Mutations in Chinese Patients with NSCLC

  • Wu, Chun-Yan;Hou, Li-Kun;Ren, Sheng-Xiang;Su, Bo;Chen, Gang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7885-7889
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    • 2014
  • Background: Activating mutations of epidermal growth factor receptor (EGFR) could predict response to tyrosine kinase inhibitor (TKI) treatment in patients with non-small cell lung cancer (NSCLC). However, the detection of EGFR mutation is frequently challenging in clinical practice for the lack of tumor tissue. The aim of this study was to investigate the feasibility of performing EGFR mutation testing on various types of liquid-based cytology (LBC) samples. Materials and Methods: A total of 434 liquid-based cytology samples were collected from March 2010 and November 2013. Among them, 101 with diagnosis of lung adenocarcinoma had paired surgically resected specimens. The ADx Amplification Refractory Mutation System (ADx-ARMS) was used to determine EGFR mutation status both in LBC and resected samples. Results: All liquid-based cytology samples were adequate for EGFR mutation analysis. The mutation rate was 50.5% in the 434 NSCLC patients with LBC samples and the incidence rates of EGFR mutation were consistent among different specimens. We also detected EGFR positives in 52.5% (53/101) patients with paired histologic specimens. The concordance rate of EGFR mutation between LBC samples and paired histologic specimens was 92.1%. Conclusions: Our results suggest that liquid-based cytology samples are highly reliable for EGFR mutation testing in patients with NSCLC.

A novel kit for enrichment of fecal helminth eggs

  • Eunsol Lee;Seon-Ok Back;Young-Ju Lee;Jung-Won Ju;Hee-Il Lee;Myoung-Ro Lee
    • Parasites, Hosts and Diseases
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    • v.62 no.3
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    • pp.323-329
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    • 2024
  • We developed a new concentration kit, called the ParaEgg (PE), for easy detection trematode eggs from fecal samples in endemic areas of clonorchiasis and metagonimiasis in Korea. To create a standard of detection efficiency, 120 fecal samples were examined using the water-ether concentration method (WECM). The PE kit and Mini ParaSep (PS) kit were used to compare the detection sensitivity of 100 egg-positive and 20 egg-negative samples in WECM. Additionally, stool samples, which were intentionally spiked with 10, 20, and 30 Clonorchis sinensis eggs, were evaluated to assess the sensitivity in low-infection cases. The PE and PS kits showed detection rates of 100% and 92%, respectively, from 100 egg-positive samples in WECM. Meanwhile, eggs were detected in 3 (PE) and 2 (PS) out of 20 egg-negative samples in WECM. The PE kit detected the highest number of eggs per gram of feces (727 on average), followed by the WECM (524) and PS kit (432). In fecal samples that were intentionally spiked with 10, 20, and 30 C. sinensis eggs, PE only detected eggs 2 out of 5 samples in 10 eggs spiked (40%), and the detection rates were 80% and 100%, respectively. The PE kit enabled a more accurate identification of trematode eggs because of the clearance of small fecal debris in the microscopic field. In conclusion, the PE kit is obviously helpful to detect and identify trematode eggs in stool examinations especially in endemic areas of clonorchiasis and metagonimiasis.

A Study on the Least Squared Estimator of Autoregressive Models when Consecutive Missing Observations Exist

  • Ryu, Gui-Yeol
    • Communications for Statistical Applications and Methods
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    • v.3 no.3
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    • pp.59-74
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    • 1996
  • The properties of the residuals are investigated when K-consecutive observations are interpolated. The central limit theorem is also proved for the LSE for autoregressive parameters when $\kappa4--consecutive observations are contaminated. The performance of the interpolated LSE in small samples is investigated by simulation. And the interpolated with the Yule-Walker type estimator.

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Small and Large Deformation Rheological Behaviors of Commercial Hot Pepper-Soybean Pastes

  • Choi, Su-Jin;Kang, Kyoung-Mo;Yoo, Byoung-Seung
    • Food Science and Biotechnology
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    • v.15 no.6
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    • pp.871-876
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    • 2006
  • Rheological behavior of commercial hot pepper-soybean paste (HPSP) was evaluated in small amplitude oscillatory and steady shear tests. Storage modulus (G'), loss modulus (G"), and complex viscosity (${\eta}^*$) as a function of angular frequency (${\omega}$), and shear stress (${\sigma}$) as a function of shear rate (${\gamma}$) data were obtained for 5 commercial HPSP samples. HPSP samples at $25^{\circ}C$ exhibited a non-Newtonian, shear-thinning flow behavior with high yield stresses and their flow behaviors were described by power law, Casson, and Herschel-Bulkley models. Time-dependent flow properties were also described by the Weltman, Hahn, and Figoni & Shoemaker models. Apparent viscosity over the temperature range of $5-35^{\circ}C$ obeyed the Arrhenius temperature relationship with activation energies (Ea) ranging 18.3-20.1 kJ/mol. Magnitudes of G' and G" increased with an increase in ${\omega}$, while ${\eta}^*$ decreased. G' values were higher than G" over the most of the frequency range (0.63-63 rad/sec), showing that they were frequency dependent. Steady shear viscosity and complex viscosity of the commercial HPSP did not fit the Cox-Merz rule.