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Aim: To compare the accuracy of digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) in preoperative assessment of local extent of breast cancer. Materials and methods: Lesion sizes of breast cancers on DBT and FFDM images were independently evaluated by breast radiologists. Each lesion was flagged as either mis-sized or not depending on whether the assessment of size at imaging was within 1 cm of the lesion size at surgery. Additional analyses were made by mammographic parenchymal density and by lesion size, using 2 cm as the boundary to separate the two subgroups. Statistical comparisons were performed using a repeated measures linear model on the percent mis-sized. P-values < 0.05 were considered statistically significant. Results: The dataset included 173 malignant breast lesions (mean size 23.8 mm, 43% of lesions were ≤2 cm in size) in 169 patients, two-thirds of which had heterogeneously or extremely dense breasts. Overall, the percentage of lesions mis-sized at DBT was significantly lower than at FFDM (19% versus 29%, p = 0.003). There was significantly less mis-sizing at DBT in both heterogeneously dense breasts (11.1% difference between DBT and FFDM, p = 0.016) and extremely dense breasts (15.8% difference, p = 0.024). DBT also had significantly less mis-sizing than FFDM in the subgroup of lesions that were ≤2 cm in size (14.7% difference, p = 0.005). Conclusion: DBT was significantly superior to FFDM for the evaluation of lesion size overall, and specifically for small lesions and for lesions in dense breasts. The superiority of DBT versus FFDM increased with parenchymal density. [Copyright &y& Elsevier]

Abstract: Total electron yield (TEY) measurement was applied to the scanning photoelectron microscopy (SPEM). The resultant image showed the thickness variation of a zinc overlayer deposited on an iron substrate with 18nm nominal thickness. The contrast and signal-to-noise ratio of the image were much higher than those of the images obtained by the conventional SPEM. When the order-sorting aperture (OSA) located between the Fresnel zone plate and the sample was biased to +80V relative to the sample, the contrast of the image was further improved. It also made it possible to perform microscopic X-ray absorption spectroscopy in TEY mode by preventing the unwanted photoelectrons emitted from the OSA, which can cause false TEY, from reaching the sample. Oxidized areas of the iron substrate under the thick zinc overlayer were clearly identified. [Copyright &y& Elsevier]

Abstract: Oxygen-free and amorphous Ge1Sb2Te4 thin film was obtained in an ultra-high vacuum and then annealed in situ to the stable-phase temperature. High-resolution X-ray photoelectron spectroscopy using synchrotron radiation was performed on the film at the different annealing temperatures of 100, 130, 150, 180, and 250°C. The Te 4d, Sb 4d, and Ge 3d shallow core levels as well as the valence-band spectra were acquired. In the shallow core-level spectra, we observed distinguishable changes in the Sb 4d and Ge 3d levels as the film phase changed. As the temperature increased, a higher binding-energy (BE) component appeared at the Sb 4d level, the intensity of the component increased, and the spin-orbit split feature was enhanced at the Ge 3d level. In the valence-band spectra, a slight increase was observed at 0–1, ~3, ~9, and ~12eV BE, and a decrease, at ~1.5 and ~4.5eV BE. The energy resolution employed in this study was about 150meV. [Copyright &y& Elsevier]

Locally advanced uterine cervical cancer (UCC) is treated by radiotherapy with concurrent chemotherapy, but heterogenous treatment responses are frequently observed. To better optimize therapeutic options based on molecular signatures, we performed proteogenomic analysis of UCC. UCC tissue and blood samples were collected from patients who underwent primary radiotherapy ± chemotherapy at the National Cancer Center (NCC) in Korea from July 2004 to March 2020. Most samples were obtained via biopsy. Genomic DNA for WES was isolated from frozen biopsy tumor tissues and peripheral blood buffy-coat of patients. Both global proteome and phosphoproteome were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Whole exome sequencing, RNA sequencing, global proteomics and phosphoproteomics were performed using 253, 337, and 147 cervical cancer samples, respectively. Patient-derived xenograft were established using intratongue implantation using 2 primary cell lines from sub3 and sub5, and flow cytometric analysis was performed. Fourteen significantly mutated genes (SMG) were found in our study cohort which include 5 newly identified SMGs. Mutation-phosphorylation analysis revealed association with apoptosis and actin cytoskeleton pathway. Proteogenomic analysis defined 6 molecular subtypes of UCC. Of those, 3 subtypes (i.e., Sub3, Sub5 and Sub6) were associated with treatment-resistant phenotypes. The cell-type deconvolution analysis suggested activated stroma with activation of cancer-associated fibroblast in Sub 3, while Sub5 showed low levels of activated stroma and high levels of myeloid immune cells. FACS analysis of UCC mouse models established from these 2 radio-resistant primary cell lines showed high component of PDGFRA+CAF infiltration in Sub 3, and high level of PVR+CD45+ immune cells mainly composed of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) in Sub5. For Sub6, genes and/or protein signatures represented mucin-related processes (e.g., mucin glycosylation/sugar metabolism), which are linked to metastasis-associated Tn antigen production. The proteogenomic analysis thus suggests potential targets for radiotherapy-resistant subtypes of UCC; secretory factors from activated stroma and cancer-associated fibroblast (Sub3); RHOA signaling, PVR, and PMN-MDSCs (Sub5), and keratin/chondroitin sulfate proteoglycan and Tn antigen production (Sub6). Our study shows the importance of proteogenomic analysis in unveiling the subtype specific molecular pathways of UCC that are beyond reach by genomic data alone. The validity of our molecular pathway and cellular signatures linking these pathways should be further validated through detailed functional experiments and in larger UCC cohorts. [ABSTRACT FROM AUTHOR]

The air quality of Northeast Asia cannot be improved by the individual national efforts because of the proximity of countries. To foster understanding of this problem, the Fine Particle Research Initiative in East Asia considering National Differences (FRIEND) Project was launched in 2020. During the first FRIEND campaign conducted from December 15, 2020 to January 15, 2021, gaseous and aerosol components were monitored simultaneously with high temporal resolution at the following key sites in Northeast Asia: Ulaanbaatar, Mongolia; Beijing, China; Seosan and Seoul, Republic of Korea; and Noto, Japan. The chemical components of PM 1.0 were monitored with Aerosol Chemical Speciation Monitors (ACSMs) at the Beijing, Seoul, and Noto sites. Over the upwind region of Northeast Asia (Beijing and Seoul), sulfate aerosol (SO 4 2−) was a high as a fraction of PM 1.0 and nitrate aerosol (NO 3 −) was high, whereas over the downwind region (Noto), SO 4 2− was high and NO 3 − was low. We used regional numerical modeling to clarify the reason for these distinctive PM 1.0 differences over the upwind and downwind regions. The model also reproduced higher NO 3 − in the upwind region and higher SO 4 2− in the downwind region, and captured the ACSMs measurements based on the statistical analyses. The conversion ratio from SO 2 to SO 4 2− (F S) indicated lower oxidation over the Asian continent and increased oxidation toward the downwind region. The OH radical and cloud fraction suggested that the gas- and aqueous-phase SO 2 oxidation processes were inactive over the Asian continent. In contrast to F S , the conversion ratio from HNO 3 to NO 3 − (F N) indicated a higher production ratio over the Asian continent and a strong decline toward the downwind region. HNO 3 concentration in northeastern China was close to zero, whereas NH 3 concentration was high, suggesting NH 3 -rich conditions where HNO 3 was fully neutralized to form NO 3 −, whereas the conditions were NH 3 -poor toward the downwind region. Therefore, these factors govern the transformation process of PM 1.0 during long-range transport from the upwind to downwind region in Northeast Asia and determine the distinctive features of inorganic PM 1.0. [Display omitted] • FRIEND project identified the distinctive difference in inorganic PM 1.0 components. • Sulfate (SO 4 2−) was low at Beijing and Seoul whereas high at Noto (Japan). • An inactive SO 2 oxidation process was found over the Asian continent. • Nitrate (NO 3 −) was high over the Asian continent and declined toward downwind. • NH 3 -rich status can maintain a formation of ammonium-nitrate (NH 4 NO 3). [ABSTRACT FROM AUTHOR]

Aims To investigate whether preoperative magnetic resonance imaging (MRI) in patients with primary breast cancer is predictive of disease-free (DFS) and overall survival and to determine the prognostic factors indicating survival. Materials and methods This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. From 2009 to 2010, 828 women with primary breast cancer and preoperative MRI were matched with 1613 women without such imaging. Patients were matched with regards to 25 patient and tumour-related covariates. A Cox proportional hazards model was used to investigate the time to recurrence and to estimate the hazard ratio for preoperative MRI. Log-rank tests and Cox proportional hazards survival analysis were carried out on total recurrence DFS and overall survival in the unmatched datasets. Results In total, 799 matched pairs were available for survival analysis. The MRI group showed a tendency towards better survival outcome; however, there were no significant differences in DFS and overall survival. Age at diagnosis (DFS hazard ratio = 0.98; overall survival hazard ratio = 1.04), larger tumour size (DFS hazard ratio = 1.01; overall survival hazard ratio = 1.02), triple negative breast cancer (DFS hazard ratio = 2.64; overall survival hazard ratio = 3.44) and the presence of lymphovascular invasion (DFS hazard ratio = 2.12; overall survival hazard ratio = 2.70) were independent significant variables for worse DFS and overall survival. Conclusion Preoperative MRI did not result in an improvement in a patient's outcome. Age at diagnosis, tumour size, molecular subtype and lymphovascular invasion were significant independent factors affecting both DFS and overall survival. [ABSTRACT FROM AUTHOR]

The Center for Fine Particle Research Initiative in East Asia considering National Differences (FRIEND) project was launched in 2020 to characterize air pollution in Northeast Asia with effective collaboration. One of the goals of this study is to elucidate the spatiotemporal characteristics of atmospheric aerosols (e.g., PM 2.5) in Northeast Asia. To achieve this objective, (1) the chemical speciation of fine particles was measured in high resolution, (2) the physical characteristics of fine particles were also elucidated, and (3) the gaseous and particulate components of the atmospheric aerosols were comprehensively monitored. The first field campaign was conducted from December 15, 2020, to January 15, 2021, and simultaneously monitored five key sites in Northeast Asia: Ulaanbaatar, Mongolia; Beijing, China; Seosan and Seoul, Republic of Korea (Korea); and Noto, Japan. The synoptic weather conditions mainly determined the periods of high PM 2.5 mass concentration. During the first high-pollution event, the air over the Northeast Asian region was generally stagnant, and the inland wind speed over China, Korea, and Japan was very low. The PM 2.5 mass concentration in Beijing, Seosan, and Seoul had increased simultaneously. Then, the prevailing westerlies in Northeast Asia caused the polluted air mass observed in Seoul to move to the background site in Noto. During the second high-pollution event, the Asian dust phenomenon occurred in the Gobi Desert and moved to all sites. Though the synoptic weather conditions largely determined the trend of the PM 2.5 mass concentrations at the five sites, the levels of chemical components in both gaseous and particulate phases were different at each site, reflecting local emission and formation characteristics. Overall, the concentrations of air pollutants were highest in Ulaanbaatar; comparable in Beijing, Seoul, and Seosan and very low in Noto. A common characteristic of the five sites was the high organic aerosol (OA) proportion in fine particles. The chemical components that increased with the PM 2.5 mass concentration were OA at Ulaanbaatar, OA and nitrate at Beijing and Seosan, nitrate at Seoul, and sulfate and OA at Noto. Further study directions for each site are discussed. • FRIEND project was launched to determine the characteristics of air pollution in Northeast Asia by simultaneous measurement. • The trend of PM 2.5 at the five sites was largely determined by synoptic weather conditions in the Northeast Asia. • The difference of major chemical components at each site reflect the significance of local emission and formation. [ABSTRACT FROM AUTHOR]

The electronic structures of the Zn-stannate nanoparticles of ZnSnO 3 and Zn 2 SnO 4 , which are the potential nano-structured semiconductor oxides for a dye sensitized solar cell (DSSC), have been investigated by employing photoemission spectroscopy (PES) and soft X-ray absorption spectroscopy (XAS), and compared to those of reference materials. The divalent and tetravalent valence states of Zn 2+ and Sn 4+ ions are confirmed experimentally. The energy levels of both the valence-band and conduction-band edges are determined experimentally. The top of the valence band in PES is slightly higher in Zn 2 SnO 4 than in ZnSnO 3 . The onset energies of the O 1 s XAS spectra of the Zn-stannates are found to be similar to each other, but higher than that of TiO 2 . The O 1 s XAS spectrum of ZnSnO 3 exhibits the higher unoccupied density of states near the bottom of the conduction band than those of Zn 2 SnO 4 , SnO 2 and ZnO, reflecting the larger number of holes in the Zn 3 d bands of ZnSnO 3 . Hence, the easier electron transfer is expected from the LUMO (lowest unoccupied molecular orbital) of a dye molecule to the conduction band of ZnSnO 3 nanoparticles on the transparent conductive electrode of a DSSC. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the effect of proton irradiation on the electrical properties of a-As2S3 in the temperature range of 323–418K and frequency range 0.1–100kHz. The variation of transport property is studied with proton irradiation dose (1×1013 ions/cm2 and 1×1015 ions/cm2). It has been observed that proton irradiation changes the dc conductivity (σ dc ), dc activation energy (ΔE dc ) and ac conductivity (σ ac (ω)). The σ dc and σ ac (ω) increases with dose of proton irradiation. The value of frequency exponent (s) decreases with the temperature and irradiation dose. These results are explained in terms of change in density of defect states in these glasses. [Copyright &y& Elsevier]

abstract: The chemical states of Bi (6 at.%)-doped GeTe thin film (GBT) in structural phase transition were investigated by high-resolution X-ray photoelectron spectroscopy (HRXPS). Clean amorphous GBT was phase changed to the NaCl-type crystalline structure by in-situ annealing under ultrahigh vacuum, during which transition, the binding energy and shape of the Te 4d core-level showed no changes, the Ge 3d core-level showed a spin-orbit split-enhanced feature with negligible chemical shift, and the Bi 4f core-level became narrower and shifted towards the higher binding energy side by 0.25 eV. We suggest that as the film phase changed to the meta-stable crystalline structure, the Ge and Bi atoms moved to more constrained sites in the electron configuration. [Copyright &y& Elsevier]

Abstract: The degradation mechanism of a polymer light-emitting device (PLED) based on poly(3,4-ethylenedioxythiophene) poly(4-styrenesulfonate) (PEDOT:PSS) was investigated by X-ray scanning photoelectron microscopy. Spectromicroscopic analysis of the surface of the emission layer (EML) of the degraded PLED revealed that island-like structures, containing sulfur (S) presumably in sulfide (–C–S–C–) and thiol (–C–S–H) configurations, were generated. The analysis results further suggest that S out-diffused from the PEDOT:PSS layer and formed sulfide and thiol configurations in the EML, and that effective conduction path channels were generated through the island-like structures for current dissipation between the electrodes, resulting in PLED degradation. [Copyright &y& Elsevier]

Abstract: An ultrafast X-ray detector system is under development at Lawrence Berkeley National Laboratory (LBNL) for application primarily to study of ultrafast magnetization dynamics. The system consists of an fs laser, an X-ray streak camera and an elliptically polarization undulator (EPU) beamline. Polarized X-rays from an EPU can be used to measure X-ray magnetic circular dichroism (XMCD) of a sample. XMCD has the unique ability to independently measure orbit and spin magnetization with sub-monolayer sensitivity and element specificity. The streak camera has simultaneously a sub-picosecond temporal resolution and a high spatial resolution. The combination of the streak camera and EPU allows us to study the transfer of angular momentum from spin to orbit to the lattice in the sample on an ultrafast time scale. We describe here the performance of the ultrafast detector, the laser and the X-ray synchronization system. The observation of the demagnetization process of different samples demonstrates the ability of the apparatus. [Copyright &y& Elsevier]

Cobalt films were deposited on a Si wafer at substrate temperatures ranging from 50 to 200 °C by metal-organic chemical vapor deposition (MOCVD) using Co2(CO)8 as a precursor. As-deposited MOCVD Co films contained low impurity contents and were obtained as a microcrystalline structure compared to sputtered Co films. After annealing at 400 °C, the resistivity of a 100 nm thick MOCVD Co film decreased to about 6 μΩ cm. This was similar to the resistivity of bulk Co and lower than that of a sputtered Co film. The decrease in resistivity coincides with grain growth in the Co film. In addition, annealing at 300 °C produced a stronger (0 0 2) fiber texture in the MOCVD Co film compared to a sputtered Co film. Grain growth appears to be coupled to the strong (0 0 2) texture evolution, possibly indicating that surface energy minimization can be a driving force for grain growth in MOCVD Co films. Formation of Co oxide inhibited grain growth and led to a high resistivity of the sputtered Co films. CoSi2 was formed in MOCVD Co films whereas Co2Si was formed in the sputtered Co films after annealing at 700 °C. [Copyright &y& Elsevier]

Abstract: Eighty-one dogs in the Chungnam province were tested for heartworm (Dirofilaria immitis) infection by ELISA (SNAP test, IDEXX Laboratories, Maine, USA). Seventeen (20.9%) of the 81 samples were found to be positive and further analyzed by 16S rRNA sequencing. In this study, all dogs tested lived outdoors. Using the χ 2 test and Fisher’s exact test, no significant differences in the prevalence of dirofilariasis were observed among different gender and age groups, although the prevalence of this disease among dogs 2–4yrs of age remains highest. Sequence analysis revealed that the species prevalent in Chungnam province were genetically distinct from the type strain of D. immitis based on the nucleotide deletion found at position nt 276 (cytosine) and nucleotide substitution at position 428 (G to A) of the partial 16S rRNA sequence of the type strain. Furthermore, phylogenetic analysis suggests at least 2 groups of D. immitis circulating in the Chungnam area between the year 2007 and 2008. [Copyright &y& Elsevier]

Abstract: Electronic structures of delafossite oxides have been investigated by using photoemission spectroscopy (PES) and soft X-ray absorption spectroscopy (XAS). T 2p XAS (, Ni) spectra of show that the valence states of Co ions are trivalent and do not change with . In contrast, Ni ions are in the mixed-valent states and the trivalent component increases with increasing . This finding suggests that the metallic nature of for low values of arises from the divalent Ni ions. The valence-band PES study of reveals that the Ni 3d states are more metallic like than the Co 3d states. [Copyright &y& Elsevier]

Abstract: The spatial concentration distribution and local electronic structure of ferromagnetic Ge1− x T x (T=Cr, Mn, Fe) DMS single crystals have been investigated by using scanning photoelectron microscopy (SPEM), X-ray absorption spectroscopy (XAS), and photoemission spectroscopy (PES). It is found that doped T ions in Ge1− x T x crystals are chemically phase-separated, suggesting that the observed ferromagnetism arises from the phase-separated T-rich phases in Ge1− x T x . [Copyright &y& Elsevier]