Stellar populations of ultraluminous infrared galaxies

Ultraluminous infrared galaxies (ULIRGs) have several types according to dominance of starburst or AGN component. We made stellar population analysis for a sample of 160 ULIRGs to study the evolution of ULIRGs. We found that the dominance of intermediate-age and old stellar populations increases along the sequence of HII-like ULIRGs, Seyfert-HII composite ULIRGs, and Seyfert 2 ULIRGs. Consequently the typical mean stellar age and the stellar mass increase along the sequence. Comparing the gas mass estimated from the CO measurements with the stellar mass estimated from the optical spectra, we found that gas fraction is anti-correlated with the stellar mass. HII-like ULIRGs with small stellar masses do not possess enough gas and the total mass, and therefore have no evolution connections with massive Seyfert 2 ULIRGs. Only massive ULIRGs may follow the evolution sequence toward AGNs, and massive HII-like ULIRGs are probably in an earlier stage of the sequence.Comment: 8 pages, 10 figures, 1 table. Accepted by Ap

Operator content of entanglement spectra in the transverse field Ising chain after global quenches

We consider the time evolution of the gaps of the entanglement spectrum for a block of consecutive sites in finite transverse field Ising chains after sudden quenches of the magnetic field. We provide numerical evidence that, whenever we quench at or across the quantum critical point, the time evolution of the ratios of these gaps allows us to obtain universal information. They encode the low-lying gaps of the conformal spectrum of the Ising boundary conformal field theory describing the spatial bipartition within the imaginary time path integral approach to global quenches at the quantum critical point

Finding Direct-Collapse Black Holes at Birth

Direct-collapse black holes (DCBHs) are currently one of the leading contenders for the origins of the first quasars in the universe, over 300 of which have now been found at $z >$ 6. But the birth of a DCBH in an atomically-cooling halo does not by itself guarantee it will become a quasar by $z \sim$ 7, the halo must also be located in cold accretion flows or later merge with a series of other gas-rich halos capable of fueling the BH's rapid growth. Here, we present near infrared luminosities for DCBHs born in cold accretion flows in which they are destined to grow to 10$^9$ M$_{\odot}$ by $z \sim$ 7. Our observables, which are derived from cosmological simulations with radiation hydrodynamics with Enzo, reveal that DCBHs could be found by the James Webb Space Telescope at $z \lesssim$ 20 and strongly-lensed DCBHs might be found in future wide-field surveys by Euclid and the Wide-Field Infrared Space Telescope at $z \lesssim$ 15.Comment: 5 pages, 2 figures, accepted by ApJ

A Multiwavelength Study of a Sample of 70 μm Selected Galaxies in the COSMOS Field. II. The Role of Mergers in Galaxy Evolution

We analyze the morphological properties of a large sample of 1503 70 μm selected galaxies in the COSMOS field spanning the redshift range 0.01 10^(12) L_☉) being up to ~50%. We also find that the fraction of spirals drops dramatically with L_(IR). Minor mergers likely play a role in boosting the infrared luminosity for sources with low luminosities (L_(IR) 1 being difficult to classify and subject to the effects of bandpass shifting; therefore, these numbers can only be considered lower limits. At z 1, the fraction of major mergers is lower, but is at least 30%-40% for ULIRGs. In a comparison of our visual classifications with several automated classification techniques we find general agreement; however, the fraction of identified mergers is underestimated due to automated classification methods being sensitive to only certain timescales of a major merger. Although the general morphological trends agree with what has been observed for local (U)LIRGs, the fraction of major mergers is slightly lower than seen locally. This is in part due to the difficulty of identifying merger signatures at high redshift. The distribution of the U – V color of the galaxies in our sample peaks in the green valley (= 1.1) with a large spread at bluer and redder colors and with the major mergers peaking more strongly in the green valley than the rest of the morphological classes. We argue that, given the number of major gas-rich mergers observed and the relatively short timescale that they would be observable in the (U)LIRG phase, it is plausible for the observed red sequence of massive ellipticals (<10^(12) M_☉) to have been formed entirely by gas-rich major mergers

The IRAC Dark Field; Far- Infrared to X-ray Data

We present 20 band photometry from the far-IR to X-ray in the Spitzer IRAC dark field. The bias for the near-IR camera on Spitzer is calibrated by observing a ~20 arcminute diameter "dark" field near the north ecliptic pole roughly every two-to-three weeks throughout the mission duration of Spitzer. The field is unique for its extreme depth, low background, high quality imaging, time-series information, and accompanying photometry including data taken with Akari, Palomar, MMT, KPNO, Hubble, and Chandra. This serendipitous survey contains the deepest mid-IR data taken to date. This dataset is well suited for studies of intermediate redshift galaxy clusters, high redshift galaxies, the first generation of stars, and the lowest mass brown dwarfs, among others. This paper provides a summary of the data characteristics and catalog generation from all bands collected to date as well as a discussion of photometric redshifts and initial and expected science results and goals. To illustrate the scientific potential of this unique dataset, we also present here IRAC color color diagrams.Comment: 12 pages, ApJS accepte

Initial experience with Vanguard(R) total knee arthroplasty

Introduction Biomet Vanguard(R) Complete Knee System is a total knee replacement system, introduced into the market in 2003: thissystem boasts a designed kneecap track or groove which allows for greater mobility and decreased loss of healthy bone during the replacement process. Clinical and radiographic results in Varese Orthopaedics Unit initial experience are reported. Materials and methods Clinical and radiographic parameters are evaluated in 29 patients who underwent TKA (Vanguard(R) Complete Knee System- Biomet Inc.) for primary gonarthrosis during the last 2 years at Orthopaedics and Traumatology Unit of Ospedale di Circolo\u2014Fondazione Macchi in Varese. ROM, type of anaesthesia, patellar pain, clinical and functional Knee Score (pre-operative), size of implant, ROM, blooding, patellar pain, VAS, clinical and func- tional Knee Score (post-operative) are analyzed. Radiographic follow-up is made at 6 and 12 months. Results Clinical and Functional Knee Score respectively improve from 47 to 88 pts and from 51 to 88 pts in pre- and post-operative period (p\0.001). Post-operatively no patellar pain, 2 pts VAS and 1215 cc blooding are reported. ROM doesn\u2019t significantly improve from pre- to post-operative. No relevant complications are reported. Due to the short follow-up, radiographic evaluation does not allow to demonstrate polyethylene liner wear. Conclusions Vanguard(R) Knee Replacement significantly shows a clinical and functional improvement in patients affected by primary gonarthrosis. Moreover, post-operative pain decrease allows early mobilization and rehabilitation

Femoral revision with the modular ZMR stem. Clinical and x-rays results at medium term follow-up

A retrospective review was conducted to evaluate the medium-term results of the ZMR modular revision taper stem. From March 1999 to December 2002, 65 consecutive hip revision surgeries were performed mostly for aseptic loosening. Femoral bone stock defects were classified according to AAOS\u2019s criteria and consisted mainly in type II and type III. A Wagner osteotomy was performed in 25 cases to remove primary implants that were cemented in 35 cases. Mean post-operative follow-up was 69 months (range, 36 to 91months). Clinical assessment at follow-up showed a significantly improved mean Harris Hip Score from 42 points preoperatively to 81 points postoperatively, while the x-ray examination did show a satisfactory distal integration of the stem in all cases and satisfactory reconstitution of the femoral bone stock in 47% of cases. The average subsidence of the stem at follow-up was under one millimeter. According to the data leg length discrepancy exceeding 15 millimeters caused significantly higher functional impairment and more pain

The Infrared Array Camera Dark Field: Far-Infrared to X-ray Data

We present 20 band photometry from the far-IR to X-ray in the Spitzer Infrared Array Camera (IRAC) dark field. The bias for the near-IR camera on Spitzer is calibrated by observing a ~20' diameter "dark" field near the north ecliptic pole roughly every two-to-three weeks throughout the mission duration of Spitzer. The field is unique for its extreme depth, low background, high quality imaging, time-series information, and accompanying photometry including data taken with Akari, Palomar, MMT, KPNO, Hubble, and Chandra. This serendipitous survey contains the deepest mid-IR data taken to date. This data set is well suited for studies of intermediate-redshift galaxy clusters, high-redshift galaxies, the first generation of stars, and the lowest mass brown dwarfs, among others. This paper provides a summary of the data characteristics and catalog generation from all bands collected to date as well as a discussion of photometric redshifts and initial and expected science results and goals. To illustrate the scientific potential of this unique data set, we also present here IRAC color-color diagrams

Air pollution & the brain: Subchronic diesel exhaust exposure causes neuroinflammation and elevates early markers of neurodegenerative disease

Background Increasing evidence links diverse forms of air pollution to neuroinflammation and neuropathology in both human and animal models, but the effects of long-term exposures are poorly understood. Objective We explored the central nervous system consequences of subchronic exposure to diesel exhaust (DE) and addressed the minimum levels necessary to elicit neuroinflammation and markers of early neuropathology. Methods Male Fischer 344 rats were exposed to DE (992, 311, 100, 35 and 0 μg PM/m3) by inhalation over 6 months. Results DE exposure resulted in elevated levels of TNFα at high concentrations in all regions tested, with the exception of the cerebellum. The midbrain region was the most sensitive, where exposures as low as 100 μg PM/m3 significantly increased brain TNFα levels. However, this sensitivity to DE was not conferred to all markers of neuroinflammation, as the midbrain showed no increase in IL-6 expression at any concentration tested, an increase in IL-1β at only high concentrations, and a decrease in MIP-1α expression, supporting that compensatory mechanisms may occur with subchronic exposure. Aβ42 levels were the highest in the frontal lobe of mice exposed to 992 μg PM/m3 and tau [pS199] levels were elevated at the higher DE concentrations (992 and 311 μg PM/m3) in both the temporal lobe and frontal lobe, indicating that proteins linked to preclinical Alzheimer\u27s disease were affected. α Synuclein levels were elevated in the midbrain in response to the 992 μg PM/m3 exposure, supporting that air pollution may be associated with early Parkinson\u27s disease-like pathology. Conclusions Together, the data support that the midbrain may be more sensitive to the neuroinflammatory effects of subchronic air pollution exposure. However, the DE-induced elevation of proteins associated with neurodegenerative diseases was limited to only the higher exposures, suggesting that air pollution-induced neuroinflammation may precede preclinical markers of neurodegenerative disease in the midbrain

Lateral parapatellar approach in primary total knee arthroplasty of the valgus knee

Background Anatomic and pathological characteristics of the valgus knee deformity represent a challenging issue for the implant of a total knee arthroplasty. The surgical approach in such cases should allow a direct ad easy exposure of the joint, easy lateral soft tissue balancing and adequate patellar tracking. Materials and Methods Twenty-four total knee arthroplasties were implanted in valgus knees between January 2002 and September 2005. A mean preoperative valgus deformity of 18\ub0 was assessed on standing x-rays. Four posterior stabilized, eighteen posterior stabilized rotating platform prosthesis and two superstabilized prosthesis were implanted in 21 patients. The surgical approach has been in all cases a lateral parapatellectomy. Follow-up assessments were obtained for all patients at a mean 23 months. They consisted of a Knee Society Score and a Patellar Score evaluation, standing AP and lateral radiograms and skyline x-rays obtained at a flection of 45\ub0. Results A mean preoperative Knee Society Clinical Score of 32,7 points (range, -4 to 64 points) significantly improved at follow-up to an average 88,8 points (range, 57 to 99 points; p<0,05). The Knee Society Function Score significantly increased from a preoperative mean score of 32,7 points (range, -20 to 75 points) to an average followup score of 81,2 points (range, 30 to 100 points; p<0.05). The Patella Score revealed absence of anterior pain in all cases but one that reported severe pain. A satisfactory patello-femoral alignement of 4.7\ub0 (range, 1\ub0 to 10\ub0) was obtained at last follow-up x-rays. One intraoperative condilar fracture occured and was treated with a single screw. Discussion The lateral approach of valgus knees led to satisfactory results in primary total knee arthroplasties in a percentage of cases comparable or superior to those presented in literature for different approaches. In addition, lateral release is performed as a part of the approach itself, allows preservation of the blood supplies of the extensor apparatus and an optimal patellar tracking in most cases. Conclusions In conclusion, the lateral approach for a primary total knee arthroplasty could be recommended in valgus knees affected by osteoarthritis because as it proved to be effective in achieving a satisfactory implant positioning and functional outcome while reporting minor complications