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We develop a new method to analyze the total electron content (TEC) depression in the ionosphere after a tsunami occurrence. We employ Gaussian process regression to accurately estimate the TEC disturbance every 30 s using satellite observations from the global navigation satellite system (GNSS) network, even over regions without measurements. We face multiple challenges. First, the impact of the acoustic wave generated by a tsunami onto TEC levels is nonlinear and anisotropic. Second, observation points are moving. Third, the measured data are not uniformly distributed in the targeting range. Nevertheless, our method always computes the electron density depression volumes, along with estimated uncertainties, when applied to the 2011 Tohoku-Oki earthquake, even with random selections of only 5 % of the 1000 GPS Earth Observation Network System receivers considered here over Japan. Also, the statistically estimated TEC depression area mostly overlaps the range of the initial tsunami, which indicates that our method can potentially be used to estimate the initial tsunami. The method can warn of a tsunami event within 15 min of the earthquake, at high levels of confidence, even with a sparse receiver network. Hence, it is potentially applicable worldwide using the existing GNSS network.

Objectives: This study aimed to determine whether texture analysis of positron emission tomography (PET) images from patients with oral squamous cell carcinoma (OSCC) can accurately diagnose cervical lymph node (LN) metastases. Methods: We conducted a retrospective chart review of 166 patients with newly pathologically diagnosed OSCC. The patient inclusion criteria were LNs exhibiting high 18F-fluorodeoxyglucose uptake [maximum standardised uptake value (SUVmax) ≥2.5] and/or LNs diagnosed as metastatic cervical LNs by a board-certified nuclear medicine physician, irrespective of the SUVmax value. The patient exclusion criteria were LNs with a metabolic tumour volume (MTV) of ≤1.0 cm3. The primary predictor variables were 31 textural indices, SUVmax and MTV. The diagnostic performance was evaluated by receiver operating characteristic (ROC) curve analysis. Results: Analyses of 91 cervical LNs (48 positives, 43 negatives) indicated that long-run emphasis (LRE) could demonstrate the highest area under the ROC curve (AUC) of 0.809. Comparison of the AUCs between SUVmax and LRE indicated that the AUC of LRE was marginally higher than that of SUVmax (p = 0.067). Furthermore, the diagnostic performance of the combination of SUVmax and LRE was more accurate than that of SUVmax alone (p = 0.04). Conclusions: The combination of SUVmax and LRE may improve the diagnostic accuracy of determining cervical LN metastases.

We evaluated whether texture analysis of positron emission tomography (PET) scans could predict the response to induction chemotherapy (ICT) in patients with oral squamous cell carcinoma (OSCC). Our retrospective cohort study included 21 patients with OSCC who underwent ICT. We extracted 31 textural indices from pretreatment PET scans and performed receiver operating characteristic curve (ROC) analysis to evaluate these indices’ efficacy in predicting ICT response. The area under the ROC curve was statistically significant for one texture index: short-zone emphasis (SZE; p = 0.041).

Observations from the new Japanese geostationary satellite Himawari-8 permit quasi-real-time estimation of global shortwave radiation at an unprecedented temporal resolution. However, accurate comparisons with ground-truthing observations are essential to assess their uncertainty. In this study, we evaluated the Himawari-8 global radiation product AMATERASS using observations recorded at four SKYNET stations in Japan and, for certain analyses, from the surface network of the Japanese Meteorological Agency in 2016. We found that the spatiotemporal variability of the satellite estimates was smaller than that of the ground observations; variability decreased with increases in the time step and spatial domain. Cloud variability was the main source of uncertainty in the satellite radiation estimates, followed by direct effects caused by aerosols and bright albedo. Under all-sky conditions, good agreement was found between satellite and ground-based data, with a mean bias in the range of 20–30 W m−2 (i.e., AMATERASS overestimated ground observations) and a root mean square error (RMSE) of approximately 70–80 W m−2. However, results depended on the time step used in the validation exercise, on the spatial domain, and on the different climatological regions. In particular, the validation performed at 2.5 min showed largest deviations and RMSE values ranging from about 110 W m−2 for the mainland to a maximum of 150 W m−2 in the subtropical region. We also detected a limited overestimation in the number of clear-sky episodes, particularly at the pixel level. Overall, satellite-based estimates were higher under overcast conditions, whereas frequent episodes of cloud-induced enhanced surface radiation (i.e., measured radiation was greater than expected clear-sky radiation) tended to reduce this difference. Finally, the total mean bias was approximately 10–15 W m−2 under clear-sky conditions, mainly because of overall instantaneous direct aerosol forcing efficiency in the range of 120–150 W m−2 per unit of aerosol optical depth (AOD). A seasonal anticorrelation between AOD and global radiation differences was evident at all stations and was also observed within the diurnal cycle.

For the prediction of the expected Tokai Earthquake (EQ), Japan Meteorological Agency (JMA) has been observing volumetric strain changes to detect its presumed pre-slip phenomena in Tokai and South Kanto regions. In 1998, an anomalous volumetric strain change, lasting for 5 days, which initially attracted much attention as a possible precursor to the Tokai EQ, was observed at Shimizu station in the Tokai area. Eventually, the Tokai EQ did not occur and the causal mechanism of the observed anomaly was unknown. However, we found variations of geoelectric potential differences (GPD) possibly associated with the anomaly by applying Principal Component Analysis (PCA) to the GPD data taken in the same area. From the polarities of the observed GPD changes, we infer that these GPD variations were caused by electrokinetic effects of groundwater motion, which might have been related with the strain changes. These results imply that the GPD observations may assist us in understanding the nature of EQ precursory phenomena.

Ce3+, Eu3+ ions singly doped, and Ce3+/Eu3+ codoped bismuth phosphate (BiPO4) nanophosphors were synthesized by a simple precipitation method and their structural, morphological, and photoluminescence properties were investigated. The structural and morphological analysis confirms the pure hexagonal crystal structure of the synthesized nanophosphors. From the Fourier transform infrared (FTIR) spectra various absorption bands respective to functional groups such as PO4 and phonon vibrations including the bending modes of the PO4 units are identified. The Ce3+ doped nanophosphors show spectrally broad luminescence in the blue (centred at 459 nm) wavelength region under the direct optical excitation of Ce3+ at 417 nm. For Eu3+ doped nanophosphors, five emission bands have been observed with 394 nm excitation wavelength. Among them, 595 nm has shown bright yellowish-orange emission. These results demonstrate that by appropriately tuning the excitation wavelength of these codoped nanophosphors the emission color in the visible region (blue and orange) can be flexibly controlled in a single sample without varying its chemical composition and size. The mechanism for this excitation energy dependent tunable emission is explained on the basis of nonenergy transfer (ET) occurring among Ce3+/Eu3+ dopant ions.

OBJETIVO: Estudar a produção de anticorpos a antígenos polissacarídicos em pacientes com ataxia-telangiectasia CASUÍSTICA E MÉTODO: Utilizando a técnica de ELISA, determinamos os níveis de IgG aos sorotipos 1, 3, 5, 6B, 9V e 14 do pneumococo em 14 pacientes com ataxia-telangiectasia, antes e após a imunização com a vacina pneumocócica 23-valente. Resposta adequada a cada sorotipo foi definida como IgG > 1,3 µg/ml ou o incremento de quatro vezes dos níveis pós em relação aos pré-imunização. RESULTADOS: Seis pacientes (43%) não responderam a todos os sorotipos analisados, quatro a apenas um sorotipo, um paciente a dois, dois a três e apenas um paciente a quatro dos seis sorotipos analisados. Nenhum paciente apresentou resposta adequada a todos os sorotipos testados. Os níveis de IgG ao pneumococo pós-imunização foram superiores aos pré-imunização para todos os sorotipos testados, exceto o 3. Apesar disso, os valores médios pós-imunização foram inferiores a 1,3 µg/ml para todos os sorotipos analisados, exceto o 14. A média de incremento da resposta foi inferior a quatro para todos os sorotipos analisados. CONCLUSÃO: Nossos resultados sugerem que pacientes com ataxia-telangiectasia têm grande risco de apresentar resposta inadequada ao pneumococo, o que pode ser uma das causas das infecções sinopulmonares de repetição.OBJECTIVE: To analyze the production of antibodies to polysaccharide antigens in patients with ataxia-telangiectasia. PATIENTS AND METHODS: We used the ELISA technique to measure the levels of IgG antibodies to serotypes 1, 3, 5, 6B, 9V and 14 of Streptococcus pneumoniae in 14 patients with ataxia-telangiectasia before and after immunization with 23-valent polysaccharide vaccine. Adequate response to individual polysaccharide can be defined as a postimmunization antibody titer equal to or greater than 1.3 µg/ml or as a minimum fourfold increase over the baseline (preimmunization) value. RESULTS: Six (43%) patients showed an absent response to all serotypes analyzed. Four patients showed adequate response to only one serotype, one patient to two serotypes, two patients to three serotypes and only one patient to four out of six serotypes analyzed. No patient had adequate response to all serotypes tested. Postimmunization pneumococcus IgG levels were higher than preimmunization levels to all serotypes analyzed, except for serotype 3. In spite of this, the mean postimmunization levels were lower than 1.3 µg/ml in all serotypes, except for serotype 14. Mean increment was less than four in all serotypes analyzed. CONCLUSION: Our results suggest that patients with ataxia-telangiectasia are at a high risk of having an impaired response to pneumococcus, which may be one of the causes of recurrent sinopulmonary infections in these patients.

OBJETIVO: Rever as publicações recentes mais relevantes sobre alergia medicamentosa e oferecer ao clínico subsídios para uma maior compreensão dessa problemática de grande relevância para a saúde pública. FONTES DOS DADOS: Busca de artigos originais e revisões indexados nas bases MEDLINE, Pubmed e Lilacs, publicados na última década, relacionando o tema de alergia a medicamentos com mecanismos imunológicos, epidemiologia, diagnóstico laboratorial, lesões cutâneas, manejo clínico e reexposição ao fármaco. SÍNTESE DOS DADOS: As reações alérgicas representam um terço das reações adversas a medicamentos. São consideradas eventos raros, mas com elevada morbimortalidade. Apesar da descrição de Gell & Coombs, útil para classificar reações alérgicas a fármacos, algumas permanecem sem classificação devido ao desconhecimento dos mecanismos imunológicos envolvidos. A existência de subpopulações de células T com características diversas daquelas comumente descritas revela a complexidade do tema e, ao mesmo tempo, elucida inúmeras questões inerentes ao mesmo. Recentemente, um novo conceito de apresentação de fármaco a linfócitos T surgiu, diante de evidências crescentes do seu envolvimento nas lesões cutâneas decorrentes de reações alérgicas a medicamentos. Na prática clínica, é muito difícil a correlação de sinais e sintomas das reações alérgicas a medicamentos com o mecanismo imunológico envolvido sem o auxílio de testes laboratoriais. Testes cutâneos in vivo e testes in vitro têm sido empregados nas suspeitas de reações alérgicas a medicamentos. No entanto, há poucos produtos comerciais adequados para sua execução. CONCLUSÕES: As reações alérgicas a fármacos constituem uma fração importante dos eventos adversos a medicamentos. É importante enfatizar a necessidade de notificação dessas reações pelos profissionais envolvidos no tratamento do paciente de forma sistematizada, por meio de ações de farmacovigilância, bem como a identificação dos possíveis mecanismos imunológicos envolvidos através de testes laboratoriais, história e avaliação clínica detalhadas.OBJECTIVE: This review addresses the most recent published literature regarding drug allergy, in order to provide physicians with a background for a better understanding of this problem of great relevance for public health. SOURCES OF DATA: The sources of data for obtaining the original and review articles published in the last 10 years were MEDLINE, Pubmed and Lilacs. The articles chosen for this review relate drug allergy to immunological mechanisms, epidemiology, clinical and laboratory evaluation, skin lesions, clinical management, and re-exposure to the drug. SUMMARY OF THE FINDINGS: Allergic reactions represent one third of adverse drug reactions. They are considered rare but with high morbimortality. Gell & Coombs' definition has been useful for classifying some types of drug allergic reactions; however, some still remain without classification because of poor knowledge of the mechanisms involved. The existence of T cell subpopulations with diverse characteristics reveals the complexity of the subject and, at the same time, elucidates several questions raised about it. It was recently postulated a new concept of chemically inert drug presentation to T cells, restricted to the major histocompatibility complex, but in a non-covalent and labile way. In clinical practice, without adequate laboratory tests, it is difficult to correlate clinical symptoms and immunological mechanisms. In vitro and in vivo skin tests have been employed in cases of suspected drug allergy reaction. However, there are very few commercially available reagents. CONCLUSIONS: Drug allergy constitutes an important problem in adverse drug reactions because of its potential of morbidity and mortality. It is necessary to emphasize the relevance of pharmacovigilance during treatment of patients, as well as the identification of possible immunological mechanisms involved in the events, through laboratory tests and detailed history and clinical evaluation.

A review of data processing of electromagnetic emission observation collected at the Complex Geophysical Observatory Karimshino (Kamchatka peninsula) during the first 5 months (July–November, 2000) of its operation is given. The main goal of this study addresses the detection of the phenomena associated with Kamchatka seismic activity. The following observations have been conducted at CGO: variations of ULF/ELF magnetic field, geoelectric potentials (telluric currents), and VLF signals from navigation radio transmitters. The methods of data processing of these observations are discussed. The examples of the first experimental results are presented.

Regular monitoring of some geophysical parameters in association with seismicity has been carried out since last year at the Japan-Russian Complex Geophysical Observatory in the Kamchatka region. This observatory was organized in connection with the ISTC project in Russia and was motivated by the results of the FRONTIER/RIKEN and FRONTIER/NASDA research projects in Japan. The main purpose of the observations is to investigate the electromagnetic and acoustic phenomena induced by the lithosphere processes (especially by seismic activity). The seismicity of the Kamchatka area is analyzed and a description of the observatory equipment is presented. At present, the activity of the observatory includes the seismic (frequency range ∆F = 0.5 – 40 Hz) and meteorological recordings, together with seismo-acoustic (∆F = 30 – 1000 Hz) and electromagnetic observations: three-component magnetic ULF variations ( ∆F = 0.003 – 30 Hz), three-component electric potential variations ( ∆F < 1.0 Hz), and VLF transmitter’s signal perturbations ( ∆F ~ 10 – 40 kHz).

The sensitivity in surface enhanced infrared spectroscopy (SEIRS) strongly depends on where the resonant excitation is spectrally located compared to the molecular vibration that is to be enhanced. In this contribution, we study the effect of coupling in the electromagnetic properties of 2D gold nanorod arrays in the IR. We also study the SEIRS activity of higher order resonant excitations in long nanoantennas to identify polaritonic signals of a supporting SiO2 layer with nanometer thickness (3 nm) on a silicon substrate.

Changes in the levels of liver cellular aetinol- and retinoic acid-binding proteins were studied after partial (about 70%) hepatectomy for 14 days in the rat. It was found that a novel binding protein designated F-type appears transiently in liver cytosol 3 days after the operation. The appearance of this protein coincides with the peak level of the alpha 1-fetoproteain. In contrast, cellular retinoic acid-binding protein was detected only the first day after hepatectomy, whereas no significant change was observed in the level of the cellular retinol-binding protein during the entire observation period. [3H]Retinol or [3H]retinoic acid complexed with serum retinol-binding protein injected intravenously into vitamin A-deficient rats 1 day after the hepatectomy was recovered 5 min or 20 min later bound specifically to cellular retinol- or retinoic acid-binding protein, respectively. The results presented here strongly suggest that each of the three cellular retinoid-binding proteins plays a distinct role in cell proliferation and differentiation.

The present work proposed to correlate serum antibody avidity and salivary antibody titers as parameters for time of infection and antigen exposure in a co-hort study evaluating leprosy patients in different periods of treatment. Colorimetric enzyme-immunoassays for salivary antibodies, serum antibody IgG titers and avidities were performed in the samples. Anti-PGL-1 IgA and IgM salivary antibodies were significantly higher in multibacillar (MB-L) patients compared to normal controls (p0.05). A good correlation was found between salivary anti-PGL-1 IgA and IgM levels in MB-L patients (r=0.41, p

The electron momentum density (EMD) in liquid silicon (Si) has been measured by synchrotron-based Compton scattering. The observed variation in the valence EMD upon melting, reflecting a semi conductor-metal transition of Si, is well explained by the collapse of the Jones zone of crystalline Si. However, the shape of the EMD of liquid Si is considerably broad and retains fairly solid (α-Si)-like characteristics. The analysis of the Fourier-transformed Compton profiles reveals that the valence electronic state in liquid Si exhibits a marked deviation from the free-electron gas features. [ABSTRACT FROM AUTHOR]

We investigated the fraction of [OII] emitters in galaxies at z ~ 0.9 as a function of the local galaxy density in the Hubble Space Telescope (HST) COSMOS 2 deg2 field. [O II] emitters are selected by the narrowband excess technique with the NB711-band imaging data taken with Suprime-Cam on the Subaru telescope. We carefully selected 614 photo-z-selected galaxies with MU3500 < -19.31 at z = 0.901 - 0.920, which includes 195 [OII] emitters, to directly compare the results with our previous study at z ~ 1.2. We found that the fraction is almost constant at 0.3 Mpc-2 < Σ10th < 10 Mpc-2. We also checked the fraction of galaxies with blue rest-frame colors of NUV -R < 2 in our photo-z-selected sample, and found that the fraction of blue galaxies does not significantly depend on the local density. On the other hand, the semi-analytic model of galaxy formation predicted that the fraction of star-forming galaxies at z ~ 0.9 decreases with increasing projected galaxy density even if the effects of the projection and the photo-z error in our analysis were taken into account. The fraction of [OII] emitters decreases from ~60% at z ~ 1.2 to ~30% at z ~ 0.9 independent of galaxy environment. The decrease of the [OII] emitter fraction could be explained mainly by the rapid decrease of star formation activity in the universe from z ~ 1.2 to z ~ 0.9. [ABSTRACT FROM AUTHOR]

In order to understand environmental effects on star formation in high-redshift galaxies, we investigate the physical relationships between the star formation activity, stellar mass, and environment for z ≃1.2 galaxies in the 2 deg² COSMOS field. We estimate star formation using the [OII]λ3727 emission line and environment from the local galaxy density. Our analysis shows that for massive galaxies (M* ≳ 1010 M⊙), the fraction of [O II] emitters in high-density environments (Σ10th ≲ 3.9 Mpc-2) is 1.7 ± 0.4 times higher than in low-density environments (Σ10th ≾ 1.5 Mpc-2), while the [OII] emitter fraction does not depend on environment for low-mass M*≲1010 M⊙ galaxies. In order to understand what drives these trends, we investigate the role of companion galaxies in our sample. We find that the fraction of [OII] emitters in galaxies with companions is 2.4 ± 0.5 times as high as that in galaxies without companions at M* ≥ 1010 M⊙. In addition, massive galaxies are more likely to have companions in high-density environments. However, although the number of star-forming galaxies increases for massive galaxies with close companions and in dense environments, the average star formation rate of star-forming galaxies at a given mass is independent of environment and the presence/absence of a close companion. These results suggest that interactions and/or mergers in a high-density environment could induce star formation in massive galaxies at z ~ 1.2, increasing the fraction of star-forming galaxies with M* ≳ 1010 M⊙. [ABSTRACT FROM AUTHOR]

Abstract  Since 1572, 33 phreatic to phreatomagmatic eruptions have occurred on Taal volcano (Philippines), some of them causing several hundred casualties. Considering the time delay between two consecutive eruptions, there is an 88% probability that Taal volcano should have already erupted. Since 1992, several phases of seismic activity have been recorded accompanied by ground deformation, opening of fissures, and surface activity. The volcanic activity of Taal appears to be controlled by dike injections and magma supply, buffered by a hydrothermal system that releases fluids and heat through boiling and subsequent steaming. In early 2005, a multidisciplinary project was launched for studying the hydrothermal activity. To map the hydrothermal system, combined surveys were carried out to investigate self-potential, total magnetic field, ground temperature and carbon dioxide soil degassing, along with satellite thermal imaging of the Main Crater Lake. The elevated temperatures and high concentrations of carbon dioxide, as well as electromagnetic anomalies, indicate large-scale hydrothermal degassing. This process is enhanced along the tectonic features (e.g., crater rim and faults) of the volcano, while active fissures opened along the E–W northern flank during the 1992–1994 seismic activity. Heat and fluids from the hydrothermal system are essentially released in the northern part of the crater, which is bounded to the South by a suspected NW–SE fault along which seismicity seems to take place, and dikes are thought to be intruded. During the January 2005 surveys, a new seismic crisis started, and the felt earthquakes prompted spontaneous evacuation of hundreds of inhabitants living on the volcano. Repeated surveys show changes of self-potential, total magnetic field, and ground temperature with time, without any noticeable spatial enlargement. These observations suggest that the northern flank located between the crater rim and the 1992–1994 fissures is connected with a deep thermal source in Main crater and is reactivated during seismic crises. This sector could be subjected to flank failure. [ABSTRACT FROM AUTHOR]

CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients. [ABSTRACT FROM AUTHOR]

We present observations of the stellar and molecular gas mass of SDSS J163909+282447.1, a luminous quasar at z = 3.84 with an extreme mass for a supermassive black hole (SMBH; MBH = 2.5 × 1010M⊙). The local SMBH mass–galaxy mass relation predicts a massive host galaxy with Mstellar ≳ 1012M⊙ for this quasar. Based on sensitive near-infrared imaging with adaptive optics (AO) using Subaru, the stellar light from the host is undetected, thus resulting in an upper limit on the mass, Mstellar < 6.3 × 1010M⊙, a factor of ≳16 less than expected. The CO(4 − 3) observations at 0.″2 resolution using the Atacama Large Millimeter/submillimeter Array indicate a molecular gas mass from CO of M⊙ and a dynamical mass within a radius of 0.45 ± 0.2 kpc of M⊙. With the SMBH accounting for ∼60% of the dynamical mass and considering the amount of molecular gas, we find an upper limit on the stellar mass to be Mstellar ≲ 1.5 × 1010M⊙, a value consistent with the limit from Subaru AO imaging. Based on these results, this SMBH has one of the largest host stellar mass deficits known given its SMBH mass; hence, it is unclear how to grow a SMBH/host galaxy to such a state since there is not enough molecular gas available to form a substantial amount of stellar mass to make up for the difference. Any physical model is likely to require an earlier phase of super-Eddington accretion onto the SMBH. [ABSTRACT FROM AUTHOR]

We report on the discovery of a merger-driven starburst at z = 1.52, PACS-787, based on high signal-to-noise ALMA observations. CO(5–4) and continuum emission (850 μm) at a spatial resolution of 0.″3 reveal two compact (r1/2 ∼ 1 kpc) and interacting molecular gas disks at a separation of 8.6 kpc, indicative of an early stage in a merger. With an SFR of 991 M⊙ yr−1, this starburst event should occur closer to final coalescence, as is usually seen in hydrodynamical simulations. From the CO size, inclination, and velocity profile for both disks, the dynamical mass is calculated through a novel method that incorporates a calibration using simulations of galaxy mergers. Based on the dynamical mass, we measure (1) the molecular gas mass, independent from the CO luminosity, (2) the ratio of the total gas mass and the CO(1–0) luminosity (), and (3) the gas-to-dust ratio, with the latter two being lower than typically assumed. We find that the high star formation triggered in both galaxies is caused by a set of optimal conditions: a high gas mass/fraction, a short depletion time (τdepl = 85 and 67 Myr) to convert gas into stars, and the interaction of likely counter-rotating molecular disks that may accelerate the loss of angular momentum. The state of interaction is further established by the detection of diffuse CO and continuum emission, tidal debris that bridges the two nuclei and is associated with stellar emission seen by HST/WFC3. This observation demonstrates the power of ALMA to study the dynamics of galaxy mergers at high redshift. [ABSTRACT FROM AUTHOR]

We present an analysis of the molecular gas properties, based on CO (2−1) emission, of 12 starburst galaxies at z ∼ 1.6 selected by having a boost (≳4×) in their star formation rate (SFR) above the average star-forming galaxy at an equivalent stellar mass. ALMA observations are acquired of six more galaxies than previously reported through our effort. As a result of the larger statistical sample, we significantly detect, for the first time at high z, a systematically lower /LIR ratio in galaxies lying above the star-forming “main sequence” (MS). Based on an estimate of αCO (i.e., the ratio of molecular gas mass to ), we convert the observational quantities (e.g., /LIR) to physical units (Mgas/SFR) that represent the gas depletion time or its inverse, the star formation efficiency. We interpret the results as indicative of the star formation efficiency increasing in a continuous fashion from the MS to the starburst regime, whereas the gas fractions remain comparable to those of MS galaxies. However, the balance between an increase in star formation efficiency and gas fraction depends on the adopted value of αCO as discussed. [ABSTRACT FROM AUTHOR]

We study the heating mechanisms and Lyα escape fractions of 35 Lyα blobs (LABs) at z ≈ 3.1 in the SSA22 field. Dust continuum sources have been identified in 11 of the 35 LABs, all with star formation rates (SFRs) above 100 M⊙ yr−1. Likely radio counterparts are detected in 9 out of 29 investigated LABs. The detection of submillimeter dust emission is more linked to the physical size of the Lyα emission than to the Lyα luminosities of the LABs. A radio excess in the submillimeter/radio-detected LABs is common, hinting at the presence of active galactic nuclei. Most radio sources without X-ray counterparts are located at the centers of the LABs. However, all X-ray counterparts avoid the central regions. This may be explained by absorption due to exceptionally large column densities along the line-of-sight or by LAB morphologies, which are highly orientation dependent. The median Lyα escape fraction is about 3% among the submillimeter-detected LABs, which is lower than a lower limit of 11% for the submillimeter-undetected LABs. We suspect that the large difference is due to the high dust attenuation supported by the large SFRs, the dense large-scale environment as well as large uncertainties in the extinction corrections required to apply when interpreting optical data. [ABSTRACT FROM AUTHOR]

We present the result of our spectroscopic follow-up observation for faint quasar candidates at z ∼ 5 in part of the Canada–France–Hawaii Telescope Legacy Survey wide field. We select nine photometric candidates and identify three z ∼ 5 faint quasars, one z ∼ 4 faint quasar, and a late-type star. Since two faint quasar spectra show the C iv emission line without suffering from a heavy atmospheric absorption, we estimate their black hole masses () and Eddington ratios (). The inferred are 9.04 ± 0.14 and 8.53 ± 0.20, respectively. In addition, the inferred are −1.00 ± 0.15 and −0.42 ± 0.22, respectively. If we adopt that , the seed black hole masses () of our z ∼ 5 faint quasars are expected to be in most cases. We also compare the observational results with a mass accretion model, where angular momentum is lost due to supernova explosions. Accordingly, of the z ∼ 5 faint quasars in our sample can be explained even if is . Since z ∼ 6 luminous qusars and our z ∼ 5 faint quasars are not on the same evolutionary track, z ∼ 6 luminous quasars and our z ∼ 5 quasars are not the same populations but different populations, due to the difference of a period of the mass supply from host galaxies. Furthermore, we confirm that one can explain of z ∼ 6 luminous quasars and our z ∼ 5 faint quasars even if their seed black holes are formed at z ∼ 7. [ABSTRACT FROM AUTHOR]

We investigate the physical conditions of ionized gas in high-z star-forming galaxies using diagnostic diagrams based on the rest-frame optical emission lines. The sample consists of 701 galaxies with an Hα detection at , from the Fiber Multi-Object Spectrograph (FMOS)-COSMOS survey, that represent the normal star-forming population over the stellar mass range , with those at being well sampled. We confirm an offset of the average location of star-forming galaxies in the Baldwin–Phillips–Terlevich (BPT) diagram ( versus ), primarily toward higher , compared with local galaxies. Based on the [S ii] ratio, we measure an electron density (), which is higher than that of local galaxies. Based on comparisons to theoretical models, we argue that changes in emission-line ratios, including the offset in the BPT diagram, are caused by a higher ionization parameter both at fixed stellar mass and at fixed metallicity, with additional contributions from a higher gas density and possibly a hardening of the ionizing radiation field. Ionization due to active galactic nuclei is ruled out as assessed with Chandra. As a consequence, we revisit the mass–metallicity relation using and a new calibration including as recently introduced by Dopita et al. Consistent with our previous results, the most massive galaxies () are fully enriched, while those at lower masses have metallicities lower than local galaxies. Finally, we demonstrate that the stellar masses, metallicities, and star formation rates of the FMOS sample are well fit with a physically motivated model for the chemical evolution of star-forming galaxies. [ABSTRACT FROM AUTHOR]

X-ray Compton scattering measurements have been carried out for fluid rubidium (Rb) from near the melting point up to the critical regions. The electron kinetic energy (KE) was derived from the valence Compton profiles and its relative variation as a function of the fluid density was compared with that of the electron gas model. Reduction in the KE occurs more slowly than that predicted by the model as the fluid density decreases and an apparent deviation in the KE from the model is observed at the densities where the fluid is still metallic. These findings suggest that a fluctuation intrinsic to the low-density electron gas causes charge inhomogeneity in valence electrons in real fluid rubidium, being coupled with ionic density fluctuations. [ABSTRACT FROM AUTHOR]

One of the important unsettled problems regarding active galactic nuclei (AGNs) is the major ionization mechanism of gas clouds in AGN narrow-line regions (NLRs). In order to investigate this issue, we present our J-band spectroscopic observations of a sample of 26 nearby Seyfert galaxies. In our study, we use the flux ratio of the following two forbidden emission lines, [Fe ii]1.257 μm and [P ii]1.188 μm, because it is known that this ratio is sensitive to the ionization mechanism. We obtain the [Fe ii]/[P ii] flux ratio or its lower limit for 19 objects. In addition to our data, we compile this flux ratio (or its lower limit) for 23 nearby Seyfert galaxies from the literature. Based on the collected data, we find that three Seyfert galaxies show very large lower limits of the [Fe ii]/[P ii] flux ratios (≳10): NGC 2782, NGC 5005, and Mrk 463. It is thus suggested that the contribution of the fast shock in the gas excitation is significantly large for them. However, more than half of the Seyfert galaxies in our sample show moderate [Fe ii]/[P ii] flux ratios (∼2), which is consistent with pure photoionization by power-law ionizing continuum emission. We also find that the [Fe ii]/[P ii] flux ratio shows no clear correlation with the radio loudness, suggesting that the radio jet is not the primary origin of shocks in NLRs of Seyfert galaxies. [ABSTRACT FROM AUTHOR]

We aim to search for hyperluminous infrared (IR) galaxies (HyLIRGs) with IR luminosity > 1013L☉ by applying the selection method of dust-obscured galaxies (DOGs). They are spatially rare but could correspond to a maximum phase of cosmic star formation (SF) and/or active galactic nucleus (AGN) activity; hence, they are a crucial population for understanding the SF and mass assembly history of galaxies. Combining the optical and IR catalogs obtained from the Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE), we performed the extensive HyLIRGs survey; we selected 5311 IR-bright DOGs with i − [22] > 7.0 and flux at 22 μm > 3.8 mJy in 14,555 deg2, where i and [22] are i-band and 22 μm AB magnitudes, respectively. Among them, 67 DOGs have reliable spectroscopic redshifts that enable us to estimate their total IR luminosity based on the spectral energy distribution fitting. Consequently, we successfully discovered 24 HyLIRGs among the 67 spectroscopically confirmed DOGs. We found that (i) i − [22] color of IR-bright DOGs correlates with the total IR luminosity and (ii) the surface number density of HyLIRGs is >0.17 deg−2. A large fraction (∼73%) of IR-bright DOGs with i − [22] > 7.5 show > 1013L☉, and the DOG criterion we adopted could be independently effective against the “W1W2-dropout method,” based on four WISE bands, for searching hyperluminous IR populations of galaxies. [ABSTRACT FROM AUTHOR]