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With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
In the collapsing phase of a molecular cloud, the molecular gas temperature is a key to understand the evolutionary process from a dense molecular cloud to stars. In order to know this, mapping observations in NH3 lines are required. Therefore, we made them based on the FUGIN (FOREST Unbiased Galactic plane Imaging survey with Nobeyama 45m telescope). The 6 maps were observed in NH3 (J,K) = (1,1), (2,2), (3,3) and H2O maser lines and obtained temperature maps; some show temperature gradient in a cloud. Additionally 72 cores were observed. These candidates were called as KAGONMA or KAG objects as abbreviation of KAgoshima Galactic Object survey with Nobeyama 45-M telescope in Ammonia lines. We show the results of two regions in W33 and discuss their astrophysical properties.
The mid-infrared range contains many spectral features associated with large molecules and dust grains such as polycyclic aromatic hydrocarbons and silicates. These are usually very strong compared to fine-structure gas lines, and thus valuable in studying the spectral properties of faint distant galaxies. In this paper, we evaluate the capability of low-resolution mid-infrared spectroscopic surveys of galaxies that could be performed by SPICA. The surveys are designed to address the question how star formation and black hole accretion activities evolved over cosmic time through spectral diagnostics of the physical conditions of the interstellar/circumnuclear media in galaxies. On the basis of results obtained with Herschel far-infrared photometric surveys of distant galaxies and Spitzer and AKARI near- to mid-infrared spectroscopic observations of nearby galaxies, we estimate the numbers of the galaxies at redshift z > 0.5, which are expected to be detected in the polycyclic aromatic hydrocarbon features or dust continuum by a wide (10 deg2) or deep (1 deg2) blind survey, both for a given observation time of 600 h. As by-products of the wide blind survey, we also expect to detect debris disks, through the mid-infrared excess above the photospheric emission of nearby main-sequence stars, and we estimate their number. We demonstrate that the SPICA mid-infrared surveys will efficiently provide us with unprecedentedly large spectral samples, which can be studied further in the far-infrared with SPICA.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
Our current knowledge of star formation and accretion luminosity at high redshift (z > 3–4), as well as the possible connections between them, relies mostly on observations in the rest-frame ultraviolet, which are strongly affected by dust obscuration. Due to the lack of sensitivity of past and current infrared instrumentation, so far it has not been possible to get a glimpse into the early phases of the dust-obscured Universe. Among the next generation of infrared observatories, SPICA, observing in the 12–350 µm range, will be the only facility that can enable us to trace the evolution of the obscured star-formation rate and black-hole accretion rate densities over cosmic time, from the peak of their activity back to the reionisation epoch (i.e., 3 < z ≲ 6–7), where its predecessors had severe limitations. Here, we discuss the potential of photometric surveys performed with the SPICA mid-infrared instrument, enabled by the very low level of impact of dust obscuration in a band centred at 34 µm. These unique unbiased photometric surveys that SPICA will perform will fully characterise the evolution of AGNs and star-forming galaxies after reionisation.
The physical processes driving the chemical evolution of galaxies in the last ~ 11Gyr cannot be understood without directly probing the dust-obscured phase of star-forming galaxies and active galactic nuclei. This phase, hidden to optical tracers, represents the bulk of the star formation and black hole accretion activity in galaxies at 1 < z < 3. Spectroscopic observations with a cryogenic infrared observatory like SPICA, will be sensitive enough to peer through the dust-obscured regions of galaxies and access the rest-frame mid- to far-infrared range in galaxies at high-z. This wavelength range contains a unique suite of spectral lines and dust features that serve as proxies for the abundances of heavy elements and the dust composition, providing tracers with a feeble response to both extinction and temperature. In this work, we investigate how SPICA observations could be exploited to understand key aspects in the chemical evolution of galaxies: the assembly of nearby galaxies based on the spatial distribution of heavy element abundances, the global content of metals in galaxies reaching the knee of the luminosity function up to z ~ 3, and the dust composition of galaxies at high-z. Possible synergies with facilities available in the late 2020s are also discussed.
The Fukushima Nuclear Energy Workers' Support (NEWS) Project Study previously showed that experiences related to the Fukushima nuclear disaster on 11 March 2011 had a great impact on psychological states, including post-traumatic stress response (PTSR) and general psychological distress (GPD), among the Fukushima nuclear plant workers. To determine the causal relationship between disaster-related experiences and levels of psychological states, we conducted a 3-year longitudinal study from 2011 to 2014.
Method
PTSR and GPD of the nuclear plant workers were assessed by annual questionnaires conducted from 2011 to 2014. The present study included a total of 1417 workers who provided an assessment at baseline (2011). A total of 4160 observations were used in the present analysis. The relationship between disaster-related experiences and psychological states over time was analysed using mixed-effects logistic regression models.
Results
A declining influence of disaster-related experiences on PTSR over time was found. However, the impact on PTSR remained significantly elevated even 3 years after the disaster in several categories of exposure including the experience of life-threatening danger, experiences of discrimination, the witnessing of plant explosion, the death of a colleague and home evacuation. The associations between GPD and disaster-related experiences showed similar effects.
Conclusions
The effects of disaster-related experiences on psychological states among the nuclear plant workers reduced over time, but remained significantly high even 3 years after the event.
The San Francisco Fire Department’s (SFFD; San Francisco, California USA) Homeless Outreach and Medical Emergency (HOME) Team is the United States’ first Emergency Medical Services (EMS)-based outreach effort using a specially trained paramedic to redirect frequent users of EMS to other types of services. The effectiveness of this program at reducing repeat use of emergency services during the first seven months of the team’s existence was examined.
Methods
A retrospective analysis of EMS use frequency and demographic characteristics of frequent users was conducted. Clients that used emergency services at least four times per month from March 2004 through May 2005 were contacted for intervention. Patterns for each frequent user before and after intervention were analyzed. Changes in EMS use during the 15-month study interval was the primary outcome measurement.
Results
A total of 59 clients were included. The target population had a median age of 55.1 years and was 68% male. Additionally, 38.0% of the target population was homeless, 43.4% had no primary care, 88.9% had a substance abuse disorder at time of contact, and 83.0% had a history of psychiatric disorder. The HOME Team undertook 320 distinct contacts with 65 frequent users during the study period. The average EMS use prior to HOME Team contact was 18.72 responses per month (SD=19.40), and after the first contact with the HOME Team, use dropped to 8.61 (SD=10.84), P<.001.
Conclusion
Frequent users of EMS suffer from disproportionate comorbidities, particularly substance abuse and psychiatric disorders. This population responds well to the intervention of a specially trained paramedic as measured by EMS usage.
TangherliniN, VillarJ, BrownJ, RodriguezRM, YehC, FriedmanBT, WadaP. The HOME Team: Evaluating the Effect of an EMS-based Outreach Team to Decrease the Frequency of 911 Use Among High Utilizers of EMS. Prehosp Disaster Med. 2016;31(6):603–607.
We present the first determination of the 18 μm luminosity function (LF) of galaxies at 0.006 < z < 0.7 (the average redshift is ~ 0.04) using the AKARI mid-infrared All-Sky Survey catalogue. We have selected a 18 μm flux-limited sample of 243 galaxies from the catalogue in the SDSS spectroscopic region. We then classified the sample into four types; Seyfert 1 galaxies (including QSOs), Seyfert 2 galaxies, LINERs and Star-Forming galaxies using mainly [OIII]/Hβ vs. [NII]/Hα line ratios obtained from the SDSS.
As a result of constructing Seyfert 1 and Seyfert 2 LFs, we found the following results; (i) the number density ratio of Seyfert 2s to Seyfert 1s is 3.98 ± 0.41 obtained from Sy1 and Sy2 LFs; this value is larger than the results obtained from optical LFs. (ii) the fraction of Sy2s in the entire AGNs may be anti-correlated with 18 μm luminosity. These results suggest that the torus structure probably depends on the mid-infrared luminosity of AGNs and most of the AGNs in the local Universe are obscured by dust.
The 7-valent pneumococcal conjugate vaccine (PCV7) is reported to decrease the incidence of community-acquired pneumonia (CAP) in children. To determine the annual incidence of CAP before the introduction of PCV7, we counted the number of children hospitalized with CAP between 2008 and 2009 in Chiba City, Japan. We investigated serotype and multilocus sequence typing (MLST) for Streptococcus pneumoniae isolates in CAP cases. The annual incidence of hospitalized CAP in children aged <5 years was 17·6 episodes/1000 child-years. In 626 episodes, S. pneumoniae was dominant in 14·7% and 0·8% of sputum and blood samples, respectively. The most common serotypes were 6B, 23F and 19F. The coverage rates of PCV7 were 66·7% and 80% in sputum samples and blood samples, respectively. MLST analysis revealed 37 sequence types. Furthermore, 54·1% of the sputum isolates and 40% of the blood isolate were related to international multidrug-resistant clones.
Japanese Disaster Medical Assistance Team (DMAT) has important duties to support and reinforce functionally insufficient key disaster hospitals in the large-scale disasters. However, it is difficult for Japanese DMAT to fulfill these duties in the current circumstances, because the DMAT consists of individual institutions and Teams have less experience to work in the other institutions. To resolve the issues, disaster drills for some DMATs which consist of several institutions have been held since 2008. We evaluated the effectiveness of the drills and educational system.
Methods
Investigation was performed by surveillance questionnaires to 129 participants in the drill (staffs from DMATs, Red Cross and local government, and sham patients). The questionnaires are: A. Was the cooperative medical practice performed smoothly? B. Was the support for hospitals conducted effectively?, C. Was the medical record for wide-area transportation completed? (for our staffs only), D. Was our activity enough? (for participants excluding us), and E. Was the drill beneficial?
Results
85 participants including 30 staffs in our institution answered the questionnaires (65.9%). The number of participants who answered ‘Yes’ was as follows: A. 48 (56.5%), B. 64 (75.3%), C. 8 (26.7%), D. 44 (83.0%) and E. 81 (95.3%).
Discussion
Although the cooperative medical practice was not so smooth, it was recognized that members in DMATs got mutual trust by their high knowledge and skills. And it was suggested that DMAT could not command and control the hospital staffs without their understanding the equipments and documentations used by DMAT. And it is ideal to change the mindset of hospital top managements towards the disaster medicine through the repeated drills.
Conclusion
The repeated disaster drills at the local area is essential to make DMAT function sufficiently.
The wettability of Pb-free Sn-based solder over the Cu-based Cu60Zr30Ti10 bulk metallic glass surface was investigated. We observed that the as-polished surface was nonwetting for the solder, which was due to the surface oxide layer of ZrOx formed in air. After complete removal of the oxide layer, a thin layer of Ag was deposited on the clean Cu60Zr30Ti10 surface. The Ag-covered Cu60Zr30Ti10 surface showed relatively high resistivity to the reoxidation even in air, and thus the wettability of the Cu60Zr30Ti10 surface for the Sn-based solder was greatly improved.
To investigate two clusters of diarrhoea cases observed in our geriatric hospital wards, the faecal specimens were analysed. Reversed passive latex agglutination assay revealed that 63·2% and 41·7% of the faecal specimens from each cluster were positive for Clostridium perfringens enterotoxin. PCR assay revealed that 71·4% and 68·8% of C. perfringens isolates from each cluster were positive for the enterotoxin gene (cpe). These observations suggested that both the clusters were outbreaks caused by enterotoxigenic C. perfringens. Subsequent pulsed-field gel electrophoresis analysis revealed that the two outbreaks were caused by different C. perfringens isolates. However, these outbreak isolates as well as other sporadic diarrhoea isolates shared a 75-kb plasmid on which the cpe gene and the tcp locus were located. The 75-kb plasmid had horizontally spread to various C. perfringens isolates and had caused outbreaks and sporadic infections. However, the site and time of the plasmid transfer are unclear.
Filmy-QCC is an organic material synthesized in the laboratory, and it exhibits red photoluminescence (PL). The peak wavelength of the PL ranges from 650 to 690 nm, depending on the mass distribution of polycyclic aromatic hydrocarbon (PAH) molecules, and the emission profile is a good match for that of the extended red emission in the Red Rectangle nebula. The quantum yield of the PL ranges from 0.009 to 0.04. When filmy-QCC is dissolved in cyclohexane, it exhibits blue PL in the wavelength range of 400–500 nm with a quantum yield of 0.12–0.16. The large width of the red PL and the large wavelength difference between the PL of the filmy-QCC as a solid film and in a solution indicate that there is a strong interaction between the components of filmy-QCC. The major components of filmy-QCC are PAHs up to 500 atomic mass units. Our laboratory data suggest that the blue luminescence observed in the Red Rectangle nebula is probably caused by small PAHs in a gaseous state, and the extended red emission is caused by larger PAHs in dust grains.
Because of its applicability to biological specimens (nonconductors),
a single-molecule-imaging technique, atomic force microscopy (AFM), has
been particularly powerful for visualizing and analyzing complex
biological processes. Comparative analyses based on AFM observation
revealed that the bacterial nucleoids and human chromatin were constituted
by a detergent/salt-resistant 30–40-nm fiber that turned into
thicker fibers with beads of 70–80 nm diameter. AFM observations of
the 14-kbp plasmid and 110-kbp F plasmid purified from Escherichia
coli demonstrated that the 70–80-nm fiber did not contain a
eukaryotic nucleosome-like “beads-on-a-string” structure.
Chloroplast nucleoid (that lacks bacterial-type nucleoid proteins and
eukaryotic histones) also exhibited the 70–80-nm structural units.
Interestingly, naked DNA appeared when the nucleoids from E. coli
and chloroplast were treated with RNase, whereas only 30-nm chromatin
fiber was released from the human nucleus with the same treatment. These
observations suggest that the 30–40-nm nucleoid fiber is formed with
a help of nucleoid proteins and RNA in E. coli and chroloplast,
and that the eukaryotic 30-nm chromatin fiber is formed without RNA. On
the other hand, the 70–80-nm beaded structures in both E.
coli and human are dependent on RNA.
The AKARI (formerly known as ASTRO-F) mission is the first Japanese satellite dedicated for large area surveys in the infrared (Murakami et al. 2004). AKARI was launched successfully on February 22nd 2006 (JST) from JAXA's Uchinoura Space Centre, Japan. AKARI is now orbiting around the Earth in a Sun-synchronous polar orbit at the altitude of 700 km. The 68.5 cm aperture telescope and scientific instruments are cooled to 6K by liquid Helium and mechanical coolers. The expected liquid Helium holding time is now found to be at least one year after the successful aperture lid-opening on 2006 April 13th (JST). AKARI will perform the most advanced all-sky survey in 6 mid- to far-infrared wavebands since the preceding IRAS mission over 2 decades ago. Deep imaging and spectroscopic surveys near the ecliptic poles with pointed observations are also on-going in 13 wavelength bands at 2-160 μm (see Table 1, details are given in Matsuhara et al. 2006). AKARI is a perfect complement to Spitzer in respect of its wide sky area and wavelength coverage. Two unique aspects of the pointing deep surveys with AKARI are: many imaging bands including the wavelength gap of Spitzer (8-24 μm), and the slitless spectroscopic capability (Ohyama et al. in this proceeding). Not only the All-Sky Survey but also the deep pointing surveys near the ecliptic poles over ~15 deg2 in total will be particularly well suited to construct the luminosity functions of the infrared galaxies, to evaluate their clustering nature, and also to discover rare, exotic objects at various redshifts out to z ~ 3. AKARI is also capable of detecting and measuring the spectrum and the fluctuations of the cosmic infrared background. The in-orbit sensitivity and spatial resolution of the surveys are found to be sufficient to achive the scientific goals listed above.
The InfraRed Camera (IRC) (Onaka et al. 2004), a wide-field (~10 × 10 arcmin2) NIR-MIR 2–26(μm) camera and spectrograph onboard the AKARI (formerly ASTRO-F) space telescope (Murakami et al. 2004), can perform slit-less spectroscopic survey. Many faint galaxies have been serendipitously detected during its in-orbit performance verification period thanks to the power of the slit-less spectroscopy. They are as faint as a few – several mJy in flux, but they can be easily recognized by their prominent spectroscopic features (e.g., PAH). Their redshift (≲0.3) can be measured through spectral template fitting over the features. We can thus obtain their basic information (redshift, activity type, and luminosity) to investigate nature of galaxies out to much greater distance at MIR than before. With the new IRC/AKARI data, we might be able to address some of the most interesting questions on galaxy evolution at z≃0.3–2 (e.g., Genzel & Cesarsky 2000; Peeters et al. 2004; Pearson 2005): What contributes to the excess found in mid-infrared source count studies with ISO/Spitzer surveys? How does the luminosity function evolve with redshift? How do the spectral features (PAH, etc.) evolve with redshift, and how they correlate with MIR and FIS luminosities with each other? We here demonstrate how MIR galaxy spectra thus obtained are useful for investigation of their basic properties.
Europium nitride (EuN), which is potentially used as an activator for nitride luminescent materials, was prepared by direct nitridation at 600 °C in a NH3 atmosphere. X-ray powder diffraction and composition analysis of the nitrided sample were carefully conducted under an oxygen-free environment. The nitrided sample was found to be mononitride with NaCl structure. An appreciable amount of oxygen (∼0.06 a.u.) was detected, but no secondary oxide phase was found. The results suggest oxygen dissolution into the lattice of EuN.