41 research outputs found
Medium Resolution Near-Infrared Spectra of the Host Galaxies of Nearby Quasars
We present medium resolution near-infrared host galaxy spectra of low
redshift quasars, PG 0844 + 349 (z=0.064), PG 1226 + 023 (z=0.158), and PG
1426+015 (z=0.086). The observations were done by using the Infrared Camera and
Spectrograph (IRCS) at the Subaru 8.2 m telescope. The full width at half
maximum of the point spread function was about 0.3 arcsec by operations of an
adaptive optics system, which can effectively resolve the quasar spectra from
the host galaxy spectra. We spent up to several hours per target and developed
data reduction methods to reduce the systematic noises of the telluric
emissions and absorptions. From the obtained spectra, we identified absorption
features of Mg I (1.503 um), Si I (1.589 um) and CO (6-3) (1.619 um), and
measured the velocity dispersions of PG 0844 + 349 to be 132+/-110 km s-1 and
PG 1426 + 015 to be 264+/-215 km s-1. By using an M_BH-sigma relation of
elliptical galaxies, we derived the black hole (BH) mass of PG 0844+349,
log(M_BH/M_SUN) = 7.7+/-5.5 and PG 1426+015, log(M_BH/M_SUN) = 9.0+/-7.5. These
values are consistent with the BH mass values from broad emission lines with an
assumption of a virial factor of 5.5.Comment: 16 pages, 5 figure
Addressing scale-up challenges and enhancement in performance of hydrogen-producing microbial electrolysis cell through electrode modifications
Bioelectrohydrogenesis using a microbial electrolysis cell (MEC) is a promising technology for simultaneous hydrogen production and wastewater treatment which uses electrogenic microbes. Microbial activity at the anode and hydrogen evolution reaction at the cathode can be controlled by electrode–microbe interaction and electron transfer. The selection of anode electrode material is governed by electrochemical oxidation of substrates and subsequent electron transfer to the anode. Similarly, a good cathodic material should reduce the overpotential at the cathode and enhance the hydrogen evolution reaction and H2 recovery. This review mainly focused on modifications in electrode materials and cheaper novel alternatives to improve the performance for MEC and overcome its scale-up challenges for practical applications. Performance of various anode and cathode materials based on Ni alloys, stainless steel, polyaniline, palladium, and carbon has been discussed. The scalability of the material should consider its inexpensive fabrication procedure and efficiency. NPRP grant NPRP12S-0304-190218 from the Qatar National Research Fund (a member of Qatar Foundation)
Acetylation changes tau interactome to degrade tau in Alzheimer’s disease animal and organoid models
© 2019 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.Alzheimer's disease (AD) is an age-related neurodegenerative disease. The most common pathological hallmarks are amyloid plaques and neurofibrillary tangles in the brain. In the brains of patients with AD, pathological tau is abnormally accumulated causing neuronal loss, synaptic dysfunction, and cognitive decline. We found a histone deacetylase 6 (HDAC6) inhibitor, CKD-504, changed the tau interactome dramatically to degrade pathological tau not only in AD animal model (ADLPAPT) brains containing both amyloid plaques and neurofibrillary tangles but also in AD patient-derived brain organoids. Acetylated tau recruited chaperone proteins such as Hsp40, Hsp70, and Hsp110, and this complex bound to novel tau E3 ligases including UBE2O and RNF14. This complex degraded pathological tau through proteasomal pathway. We also identified the responsible acetylation sites on tau. These dramatic tau-interactome changes may result in tau degradation, leading to the recovery of synaptic pathology and cognitive decline in the ADLPAPT mice11Nsciescopu
Remote sensing of Titan's troposphere with the CIRS instrument on Cassini
International audienc
Remote sensing of Titan's troposphere with the CIRS instrument on Cassini
International audienc
Remote sensing of Titan's troposphere with the CIRS instrument on Cassini
International audienc
The Tropospheric Abundance of H<SUB>2</SUB> on Titan from the Cassini CIRS Investigation
International audienc
The Tropospheric Abundance of H2 on Titan from the Cassini CIRS Investigation
International audienc
The Tropospheric Abundance of H<SUB>2</SUB> on Titan from the Cassini CIRS Investigation
International audienc