1,106 research outputs found

    Suppressed Superconductivity of the Surface Conduction Layer in Bi2_2Sr2_2CaCu2_2O8+x_{8+x} Single Crystals Probed by {\it c}-Axis Tunneling Measurements

    Full text link
    We fabricated small-size stacks on the surface of Bi2_2Sr2_2CaCu2_2O8+x_{8+x} (BSCCO-2212) single crystals with the bulk transition temperature TcT_c\simeq90 K, each containing a few intrinsic Josephson junctions. Below a critical temperature TcT_c' (\ll TcT_c), we have observed a weakened Josephson coupling between the CuO2_2 superconducting double layer at the crystal surface and the adjacent one located deeper inside a stack. The quasiparticle branch in the IVIV data of the weakened Josephson junction (WJJ) fits well to the tunneling characteristics of a d-wave superconductor(')/insulator/d-wave superconductor (D'ID) junction. Also, the tunneling resistance in the range TcT_c'<<TT<<TcT_c agrees well with the tunneling in a normal metal/insulator/d-wave superconductor (NID) junction. In spite of the suppressed superconductivity at the surface layer the symmetry of the order parameter appears to remain unaffected.Comment: 13 pages, 6 figure

    In Vitro Chemosensitivity Using the Histoculture Drug Response Assay in Human Epithelial Ovarian Cancer

    Get PDF
    The choice of chemotherapeutic drugs to treat patients with epithelial ovarian cancer has not depended on individual patient characteristics. We have investigated the correlation between in vitro chemosensitivity, as determined by the histoculture drug response assay (HDRA), and clinical responses in epithelial ovarian cancer. Fresh tissue samples were obtained from 79 patients with epithelial ovarian cancer. The sensitivity of these samples to 11 chemotherapeutic agents was tested using the HDRA method according to established methods, and we analyzed the results retrospectively. HDRA showed that they were more chemosensitive to carboplatin, topotecan and belotecan, with inhibition rates of 49.2%, 44.7%, and 39.7%, respectively, than to cisplatin, the traditional drug of choice in epithelial ovarian cancer. Among the 37 patients with FIGO stage Ⅲ/Ⅳ serous adenocarcinoma who were receiving carboplatin combined with paclitaxel, those with carboplatin-sensitive samples on HDRA had a significantly longer median disease-free interval than patients with carboplatin- resistant samples (23.2 vs. 13.8 months, p<0.05), but median overall survival did not differ significantly (60.4 vs. 37.3 months, p=0.621). In conclusion, this study indicates that HDRA could provide useful information for designing individual treatment strategies in patients with epithelial ovarian cancer

    Prediction Forecast for Culex tritaeniorhynchus Populations in Korea

    Get PDF
    AbstractObjectivesJapanese encephalitis is considered as a secondary legal infectious disease in Korea and is transmitted by mosquitoes in the summer season. The purpose of this study was to predict the ratio of Culex tritaeniorhynchus to all the species of mosquitoes present in the study regions.MethodsFrom 1999 to 2012, black light traps were installed in 10 regions in Korea (Busan, Gyeonggi, Gangwon, Chungbuk, Chungnam, Jeonbuk, Jeonnam, Gyeongbuk, Gyeongnam, and Jeju) to capture mosquitoes for identification and classification under a dissecting microscope. The number of mosquitoes captured/week was used to calculate its daily occurrence (mosquitoes/trap/night). To predict the characteristics of the mosquito population, an autoregressive model of order p (AR(p)) was used to execute the out-of-sample prediction and the in-sample estimation after presumption.ResultsCompared with the out-of-sample method, the sample-weighted regression method's case was relatively superior for prediction, and this method predicted a decrease in the frequency of Cx. tritaeniorhynchus for 2013. However, the actual frequency of this species showed an increase in frequency. By contrast, the frequency rate of all the mosquitoes including Cx. tritaeniorhynchus gradually decreased.ConclusionThe number of patients with Japanese encephalitis has been strongly associated with the occurrence and density of vector mosquitoes, and the importance of this infectious disease has been highlighted since 2010. The 2013 prediction indicated an increase after an initial decrease, although the ratio of the two mosquito species decreased. The increase in vector density may be due to changes in temperature and the environment. Thus, continuous prevalence prediction is warranted

    Far-Ultraviolet Cooling Features of the Antlia Supernova Remnant

    Full text link
    We present far-ultraviolet observations of the Antlia supernova remnant obtained with Far-ultraviolet IMaging Spectrograph (FIMS, also called SPEAR). The strongest lines observed are C IV 1548,1551 and C III 977. The C IV emission of this mixed-morphology supernova remnant shows a clumpy distribution, and the line intensity is nearly constant with radius. The C III 977 line, though too weak to be mapped over the whole remnant, is shown to vary radially. The line intensity peaks at about half the radius, and drops at the edge of the remnant. Both the clumpy distribution of C IV and the rise in the C IV to C III ratio towards the edge suggest that central emission is from evaporating cloudlets rather than thermal conduction in a more uniform, dense medium.Comment: 9 pages, 4 figures, will be published in ApJ December 1, 2007, v670n2 issue. see http://astro.snu.ac.kr/~jhshinn/ms.pd

    The resistance anomaly in the surface layer of Bi2_2Sr2_2CaCu2_2O8+x_{8+x} single crystals under radio-frequency irradiation

    Full text link
    We observed that radio-frequency (rf) irradiation significantly enhances the cc-axis resistance near and below the superconducting transition of the CuO2_{2} layer in contact with a normal-metal electrode on the surface of Bi2_{2}Sr2_{2}CaCu2_{2}O8+x_{8+x} single crystals. We attribute the resistance anomaly to the rf-induced charge-imbalance nonequilibrium effect in the surface CuO2_{2} layer. The relaxation of the charge-imbalance in this highly anisotropic system is impeded by the slow quasiparticle recombination rate, which results in the observed excessive resistance.Comment: 8 pages, 5 figure

    Polymorphism of a COLIA1 Gene Sp1 Binding Site in Korean Women with Pelvic Organ Prolapse

    Get PDF
    PURPOSE: To evaluate the possible influence of G-->T substitution at the Sp1-binding site of the COLIA1 gene on the risk of pelvic organ prolapse (POP). MATERIALS AND METHODS: The study group consisted of 15 women with advanced stage POP. Fifteen control subjects with uterine myomas among the postmenopausal women were matched for age and parity. DNA was obtained from peripheral blood leukocytes. The fragments of the first intron of the COLIA1 gene were amplified by real time polymerase chain reaction. The polymorphism was identified using LightCycler Technology with hybridization probes. Sequencing reactions were performed on each template using commercial primer. RESULTS: Two groups had no significant difference in medical history, surgical, and smoking history. The homozygous peaks in two groups were noted at 57 on melting curve analysis. Sequencing reactions confirmed the G/G alleles in the 30 specimens tested. We could not find any polymorphism at the Sp1-binding site in COLIA1 gene with advanced stage POP. Statistical significance was considered to be p < .05. CONCLUSION: The polymorphism of the Sp1-binding site in the COLIA1 gene did not contribute to the development of POP in Korea.ope

    Comparison of physicochemical traits of dry-cured ham from purebred Berkshire and crossbred Landrace × Yorkshire × Duroc (LYD) pigs

    Get PDF
    This study was conducted to compare the physicochemical traits of dry-cured hams made from two different pig breeds: Berkshire and Landrace × Yorkshire × Duroc (LYD). Pigs were slaughtered at a live weight of approximately 110 kg and cooled at 0°C for 24 h in a chilling room. Then, the ham portion of the carcasses were cut and processed by dry-curing for physicochemical analyses. The dry-cured hams from Berkshire contain higher crude protein, fat, and ash level than those from LYD, whereas the hams from LYD had higher moisture contents than those from Berkshire(p < 0.05). The pH values of the hams from Berkshire were lower than those from LYD (p < 0.05). The hams from Berkshire had lower L* and b* values than those from LYD (p < 0.05). Palmitoleic acid (C16:1), oleic acid (C18:1), elaidic acid (C18:1t), monounsaturated fatty acids, and ratio of n-6 and n-3 fatty acids (n-6/n-3) in the ham from Berkshire were higher than LYD (p < 0.05). Free amino acids such as aspartic acid, threonine, serine, asparagine, glutamic acid, and lysine in hams from Berkshire were higher than those from LYD (p < 0.05). The microbial population had no significant difference between Berkshire and LYD dry-cured ham. The cross sections of dry cured ham showed difference from different breeds using scanning electron microscope and indicates some differences in texture. Considering the meat quality parameters of ham, hams from Berkshire could provide variety of ham for consumer who are seeking various different qualities and stories

    Tetrahydroabietic Acid, a Reduced Abietic Acid, Inhibits the Production of Inflammatory Mediators in RAW264.7 Macrophages Activated with Lipopolysaccharide

    Get PDF
    Abietic acid (AA), the main component of the rosin fraction of oleoresin synthesized by conifer species, has been reported to have anti-inflammatory effects. AA is a weak contact allergen; however, compounds resulting from its oxidation by air elicit stronger allergic response. Hydrogenation of the conjugated double bonds of AA, as in tetrahydroabietic acid (THAA), decreases its susceptibility to air oxidation and would thus reduce the allergenicity of AA. The aim of this study was to investigate whether THAA could exert anti-inflammatory effects to the same extent as AA in RAW264.7 macrophages activated with the endotoxin lipopolysaccharide (LPS). THAA and AA inhibited the production of nitric oxide (NO) and prostaglandin E2 by suppressing the expression of inducible NO synthase and cyclooxygenase-2, respectively, in LPS-activated RAW264.7 macrophages. They also inhibited the LPS-induced production of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. Both THAA and AA prevented the LPS-induced nuclear translocation of the nuclear factor-κB/p65 subunit, suggesting that THAA may inhibit the production of pro-inflammatory mediators through the same mechanism as AA. In comparison, the anti-inflammatory effects of THAA and AA were almost identical, indicating that THAA retains the anti-inflammatory activity of AA at least in LPS-activated RAW264.7 macrophages
    corecore