Given the mode of transmission of Middle East respiratory syndrome (MERS), healthcare workers (HCWs) in contact with MERS patients are expected to be at risk of MERS infections. We evaluated the ...prevalence of MERS coronavirus (CoV) immunoglobulin (Ig) G in HCWs exposed to MERS patients and calculated the incidence of MERS-affected cases in HCWs. We enrolled HCWs from hospitals where confirmed MERS patients had visited. Serum was collected 4 to 6 weeks after the last contact with a confirmed MERS patient. We performed an enzyme-linked immunosorbent assay (ELISA) to screen for the presence of MERS-CoV IgG and an indirect immunofluorescence test (IIFT) to confirm MERS-CoV IgG. We used a questionnaire to collect information regarding the exposure. We calculated the incidence of MERS-affected cases by dividing the sum of PCR-confirmed and serology-confirmed cases by the number of exposed HCWs in participating hospitals. In total, 1169 HCWs in 31 hospitals had contact with 114 MERS patients, and among the HCWs, 15 were PCR-confirmed MERS cases in study hospitals. Serologic analysis was performed for 737 participants. ELISA was positive in five participants and borderline for seven. IIFT was positive for two (0.3%) of these 12 participants. Among the participants who did not use appropriate personal protective equipment (PPE), seropositivity was 0.7% (2/294) compared to 0% (0/443) in cases with appropriate PPE use. The incidence of MERS infection in HCWs was 1.5% (17/1169). The seroprevalence of MERS-CoV IgG among HCWs was higher among participants who did not use appropriate PPE.
The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations. Antineutrinos from six 2.8 ... GW(th) reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors located at 294 and 1383 m, respectively, from the reactor array center. In the 229 d data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of antineutrinos in the far detector is 0.920±0.009(stat)±0.014(syst). From this deficit, we determine sin(2)2θ(13)=0.113±0.013(stat)±0.019(syst) based on a rate-only analysis.
Manic episodes are one of the major diagnostic symptoms in a spectrum of neuropsychiatric disorders that include schizophrenia, obsessive-compulsive disorder and bipolar disorder (BD). Despite a ...possible association between BD and the gene encoding phospholipase Cγ1 (PLCG1), its etiological basis remains unclear. Here, we report that mice lacking phospholipase Cγ1 (PLCγ1) in the forebrain (Plcg1
; CaMKII) exhibit hyperactivity, decreased anxiety-like behavior, reduced depressive-related behavior, hyperhedonia, hyperphagia, impaired learning and memory and exaggerated startle responses. Inhibitory transmission in hippocampal pyramidal neurons and striatal dopamine receptor D1-expressing neurons of Plcg1-deficient mice was significantly reduced. The decrease in inhibitory transmission is likely due to a reduced number of γ-aminobutyric acid (GABA)-ergic boutons, which may result from impaired localization and/or stabilization of postsynaptic CaMKII (Ca
/calmodulin-dependent protein kinase II) at inhibitory synapses. Moreover, mutant mice display impaired brain-derived neurotrophic factor-tropomyosin receptor kinase B-dependent synaptic plasticity in the hippocampus, which could account for deficits of spatial memory. Lithium and valproate, the drugs presently used to treat mania associated with BD, rescued the hyperactive phenotypes of Plcg1
; CaMKII mice. These findings provide evidence that PLCγ1 is critical for synaptic function and plasticity and that the loss of PLCγ1 from the forebrain results in manic-like behavior.
Gliomas are associated with high mortality because of their exceedingly invasive character. As these tumors acquire their invasiveness from low-grade tumors, it is very important to understand the ...detailed molecular mechanisms of invasion onset. Recent evidences suggest the significant role of microRNAs in tumor invasion. Thus, we hypothesized that deregulation of microRNAs may be important for the malignant progression of gliomas. We found that the aberrant expression of miR-21 is responsible for glioma invasion by disrupting the negative feedback circuit of Ras/MAPK signaling, which is mediated by Spry2. Upregulation of miR-21 was triggered by tumor microenvironmental factors such as hyaluronan and growth factors in glioma cells lacking functional phosphatase and tensin homolog (PTEN), but not harboring wild-type PTEN. Consistently with these in vitro results, Spry2 protein levels were significantly decreased in 79.7% of invasive WHO grade II-IV human glioma tissues, but not in non-invasive grade I and normal tissues. The Spry2 protein levels were not correlated with their mRNA levels, but inversely correlated with miR-21 levels. Taken together, these results suggest that the post-transcriptional regulation of Spry2 by miR-21 has an essential role on the malignant progression of human gliomas. Thus, Spry2 may be a novel therapeutic target for treating gliomas.
Context. The near-Earth asteroid 3200 Phaethon (1983 TB) is an attractive object not only from a scientific viewpoint but also because of JAXA’s DESTINY+ target. The rotational lightcurve and spin ...properties were investigated based on the data obtained in the ground-based observation campaign of Phaethon. Aims. We aim to refine the lightcurves and shape model of Phaethon using all available lightcurve datasets obtained via optical observation, as well as our time-series observation data from the 2017 apparition. Methods. Using eight 12-m telescopes and an optical imager, we acquired the optical lightcurves and derived the spin parameters of Phaethon. We applied the lightcurve inversion method and SAGE algorithm to deduce the convex and non-convex shape model and pole orientations. Results. We analysed the optical lightcurve of Phaethon and derived a synodic and a sidereal rotational periods of 3.6039 h, with an axis ratio of a∕b = 1.07. The ecliptic longitude (λp) and latitude (βp) of the pole orientation were determined as (308°, −52°) and (322°, −40°) via two independent methods. A non-convex model from the SAGE method, which exhibits a concavity feature, is also presented.
The RENO experiment reports more precisely measured values of θ_{13} and |Δm_{ee}^{2}| using ∼2200 live days of data. The amplitude and frequency of reactor electron antineutrino (νover ¯_{e}) ...oscillation are measured by comparing the prompt signal spectra obtained from two identical near and far detectors. In the period between August 2011 and February 2018, the far (near) detector observed 103 212 (850 666) νover ¯_{e} candidate events with a background fraction of 4.8% (2.0%). A clear energy and baseline dependent disappearance of reactor νover ¯_{e} is observed in the deficit of the measured number of νover ¯_{e}. Based on the measured far-to-near ratio of prompt spectra, we obtain sin^{2}2θ_{13}=0.0896±0.0048(stat)±0.0047(syst) and |Δm_{ee}^{2}|=2.68±0.12(stat)±0.07(syst)×10^{-3} eV^{2}.
Isostructural metal-insulator transition in VO2 Lee, D; Chung, B; Shi, Y ...
Science (American Association for the Advancement of Science),
11/2018, Letnik:
362, Številka:
6418
Journal Article
Recenzirano
Odprti dostop
Separating structure and electrons in VO2Above 341 kelvin—not far from room temperature—bulk vanadium dioxide (VO2) is a metal. But as soon as the material is cooled below 341 kelvin, VO2 turns into ...an insulator and, at the same time, changes its crystal structure from rutile to monoclinic. Lee et al. studied the peculiar behavior of a heterostructure consisting of a layer of VO2 placed underneath a layer of the same material that has a bit less oxygen. In the VO2 layer, the structural transition occurred at a higher temperature than the metal-insulator transition. In between those two temperatures, VO2 was a metal with a monoclinic structure—a combination that does not occur in the absence of the adjoining oxygen-poor layer.Science, this issue p. 1037The metal-insulator transition in correlated materials is usually coupled to a symmetry-lowering structural phase transition. This coupling not only complicates the understanding of the basic mechanism of this phenomenon but also limits the speed and endurance of prospective electronic devices. We demonstrate an isostructural, purely electronically driven metal-insulator transition in epitaxial heterostructures of an archetypal correlated material, vanadium dioxide. A combination of thin-film synthesis, structural and electrical characterizations, and theoretical modeling reveals that an interface interaction suppresses the electronic correlations without changing the crystal structure in this otherwise correlated insulator. This interaction stabilizes a nonequilibrium metallic phase and leads to an isostructural metal-insulator transition. This discovery will provide insights into phase transitions of correlated materials and may aid the design of device functionalities.
Design of the RAON accelerator systems Jeon, D.; Hong, I. S.; Kim, H. J. ...
Journal of the Korean Physical Society,
10/2014, Letnik:
65, Številka:
7
Journal Article
Recenzirano
The RAON is the name of the heavy ion accelerator facility under construction in Korea that includes the In-flight Fragment (IF) and Isotope Separation On-Line (ISOL) facilities to support ...cutting-edge research in various science fields. The superconducting linac is the driver for the IF facility that can accelerate beams from proton to uranium with 200 MeV/u, 400 kW (for uranium beam). A 70-MeV, 1-mA H
−
cyclotron is the driver for the ISOL facility and is followed by a post-accelerator consisting of s superconducting linac that can accelerate rare-isotope (RI) beams and deliver them to experimental halls. These facilities provide high-intensity stable ion and rare isotope (RI) beams for domestic and international users. In this paper, design and prototyping efforts for the RAON accelerator systems are presented.
Endocrine treatment is recommended by clinical guidelines as the preferred treatment option for premenopausal as well as postmenopausal women with hormone receptor-positive, HER2-negative metastatic ...breast cancer. In real-world clinical practice, however, a substantial number of patients are treated with chemotherapy. We aimed to compare the clinical antitumour activity and safety of palbociclib plus endocrine therapy with that of capecitabine chemotherapy in premenopausal women with hormone receptor-positive, HER2-negative metastatic breast cancer.
This multicentre, open-label, randomised, phase 2 study was done in 14 academic institutions in South Korea. Premenopausal women aged 19 years or older with hormone receptor-positive, HER2-negative breast cancer that had relapsed or progressed during previous tamoxifen therapy and with an Eastern Cooperative Oncology Group performance status of 0–2 were included. One line of previous chemotherapy for metastatic breast cancer was allowed. Patients were randomly assigned, using a random permuted block design (with a block size of two), to receive palbociclib plus combination endocrine therapy (oral exemestane 25 mg per day for 28 days and oral palbociclib 125 mg per day for 21 days every 4 weeks plus leuprolide 3·75 mg subcutaneously every 4 weeks) or chemotherapy (oral capecitabine 1250 mg/m2 twice daily for 2 weeks every 3 weeks). Randomisation was stratified by previous chemotherapy for metastatic breast cancer and visceral metastasis. The primary endpoint was progression-free survival. All analyses were done in a modified intention-to-treat population that excluded patients who did not receive study medication. This study is registered with ClinicalTrials.gov, NCT02592746, and is ongoing for follow-up of overall survival.
Between June 15, 2016, and Dec 10, 2018, 189 patients were enrolled, of whom 184 were randomly assigned to the palbociclib plus endocrine therapy group (n=92) or the capecitabine group (n=92). Six patients in the capecitabine group withdrew from the study before drug administration; therefore, 92 patients in the palbociclib plus endocrine therapy group and 86 patients in the capecitabine group were included in the modified intention-to-treat analyses. 46 (50%) of 92 patients in the palbociclib plus endocrine therapy group and 45 (51%) of 92 in the capecitabine group were treatment naive for metastatic breast cancer. During a median follow-up of 17 months (IQR 9–22), median progression-free survival was 20·1 months (95% CI 14·2–21·8) in the palbociclib plus endocrine therapy group versus 14·4 months (12·1–17·0) in the capecitabine group (hazard ratio 0·659 95% CI 0·437–0·994, one-sided log-rank p=0·0235). Treatment-related grade 3 or worse neutropenia was more common in the palbociclib plus endocrine therapy group than in the capecitabine group (69 75% of 92 vs 14 16% of 86 patients). 2 (2%) patients in the palbociclib plus endocrine therapy group and 15 (17%) patients in the capecitabine group had treatment-related serious adverse events. No treatment-related deaths occurred.
Exemestane plus palbociclib with ovarian function suppression showed clinical benefit compared with capecitabine in terms of improved progression-free survival in premenopausal patients with hormone receptor-positive, HER2-negative metastatic breast cancer. Palbociclib plus exemestane with ovarian suppression is an active treatment option in premenopausal patients with hormone receptor-positive, HER2-negative metastatic breast cancer who have been pretreated with tamoxifen.
Pfizer, Shinpoong, and Daewoong Korea and Takeda.