Meteor Radar Study of Ionospheric Wind at Kyoto

This paper describes the results of meteor radar observations which have been carried out at Kyoto University since December, 1977. The radar, a coherent pulse doppler radar with a transmitting frequency of 31.57 MHz and a nominal peak power of 10 kW, is able to detect wind fields at meteor regions of 80-110 km. The solar semidiurnal tide generally dominates the wind oscillations at these heights, while a diurnal tide of comparable magnitude reveals itself in a less regular manner. Some anomalies in the amplitude and phase characteristics of the tides are shown, which might be related to a possible interaction with winds and waves, or to some disturbed conditions in the earth's atmosphere. Also planetary scale waves such as quasi-2-day oscillations and resonantly magnified gravity-mode waves have also been found there. Hence, the meteor radar, together with its cooperation with other observations, will helps us understand the dynamical process of atmospheric waves on a global scale

Attenuation performance of geosynthetic sorption sheets against arsenic subjected to compressive stresses

The attenuation layer method has been considered an effective countermeasure to deal with excavated soils and rocks containing geogenic toxic elements like arsenic (As). The geosynthetic sorption sheet is a geosynthetic product that can be employed in the attenuation layer method applications as a sorption material. The sorption sheets used in the attenuation layer will be inevitably subjected to overburdened loads in the field. In this study, laboratory column experiments are conducted to evaluate the attenuation performance of the geosynthetic sorption sheets coated with hydrotalcite as sorbent against As under different overburden pressure conditions (10, 100, and 200 kPa). Experimental results showed that the cumulative sorption masses of As for 200 kPa cases are approximately 10.5–13.3 times greater than that for 10 kPa cases. Microstructure characterizations of the geosynthetic sorption sheet before and after loading were also detected. More compacted and involved fiber configuration as a result of higher loading produces a more effective contact between As solution and hydrotalcite. The presence of partial dissolution of hydrotalcite is confirmed through the chemical analysis of effluent. However, hydrotalcite would gradually become stable during continuous use

Mislocalization of Nucleocytoplasmic Transport Proteins in Human Huntington’s Disease PSC-Derived Striatal Neurons

Huntington’s disease (HD) is an inherited neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene (HTT). Disease progression is characterized by the loss of vulnerable neuronal populations within the striatum. A consistent phenotype across HD models is disruption of nucleocytoplasmic transport and nuclear pore complex (NPC) function. Here we demonstrate that high content imaging is a suitable method for detecting mislocalization of lamin-B1, RAN and RANGAP1 in striatal neuronal cultures thus allowing a robust, unbiased, highly powered approach to assay nuclear pore deficits. Furthermore, nuclear pore deficits extended to the selectively vulnerable DARPP32 + subpopulation neurons, but not to astrocytes. Striatal neuron cultures are further affected by changes in gene and protein expression of RAN, RANGAP1 and lamin-B1. Lowering total HTT using HTT-targeted anti-sense oligonucleotides partially restored gene expression, as well as subtly reducing mislocalization of proteins involved in nucleocytoplasmic transport. This suggests that mislocalization of RAN, RANGAP1 and lamin-B1 cannot be normalized by simply reducing expression of CAG-expanded HTT in the absence of healthy HTT protein

Development of a multistage laser frequency stabilization for an interferometric gravitational-wave detector

Laser frequency stabilization is essential for interferometric gravitational-wave detectors to attain their target sensitivity. We have designed a multistage laser frequency stabilization system which has been applied in the development of the TAMA 300 gravitational-wave detector in Japan. The control topology consisting of two cascaded loops were employed to secure high feedback gain and reliable detector operation and thus allow the best frequency stability and uninterrupted long-term observation. We achieved simultaneously a frequency stability of 5 × 10^(−5) Hz/√HZ , and a common-mode rejection ratio (which reduces the coupling of frequency noise to spurious signals in the detector) of 37 dB. The developed system enabled us to operate TAMA 300 with sufficient sensitivity and stability that it had the potential to register gravitational-wave events. The system was confirmed to be suitable for a gravitational-wave detector from the observation run of TAMA 300

Invariants of structures

We give a categorification of the notion of a mathematical structure originally given by Bourbaki in their set theory textbook. We show that any isomorphism-invariant property of a finite structure can be computed by counting the number of isomorphic copies of small substructures it contains. Our main theorem in this direction is a generalization of the classical result of Hilbert about elementary symmetric polynomials generating the algebra of all symmetric polynomials. We also show that, for structures built from sets, the Yoneda functor extends to a canonical embedding of any such category of structures into an associated category of structures in the sense of classical model theory