Numerical Simulations of Axisymmetric Flows in Astrophysics and their Visualization by a Video Movie

Numerical simulations of axisymmetric flow in four different astrophysical situations are performed, and their results are visualized by using a video movie. The situations considered are : 1) an accretion flow on to a gravitating compact object allowing maximum accrection ; 2) a jet formation in a flow past a gravitating rigid sphere ; 3) an interaction between a supersonic wind from a central object and a uniform supersonic incident flow ; 4) a wind bubble formed by spherical supersonic wind. The video tape of VHS/NTSC format is available from the author

Diffusion tensor model links to neurite orientation dispersion and density imaging at high b-value in cerebral cortical gray matter

Diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) are widely used models to infer microstructural features in the brain from diffusion-weighted MRI. Several studies have recently applied both models to increase sensitivity to biological changes, however, it remains uncertain how these measures are associated. Here we show that cortical distributions of DTI and NODDI are associated depending on the choice of b-value, a factor reflecting strength of diffusion weighting gradient. We analyzed a combination of high, intermediate and low b-value data of multi-shell diffusion-weighted MRI (dMRI) in healthy 456 subjects of the Human Connectome Project using NODDI, DTI and a mathematical conversion from DTI to NODDI. Cortical distributions of DTI and DTI-derived NODDI metrics were remarkably associated with those in NODDI, particularly when applied highly diffusion-weighted data (b-value = 3000 sec/mm2). This was supported by simulation analysis, which revealed that DTI-derived parameters with lower b-value datasets suffered from errors due to heterogeneity of cerebrospinal fluid fraction and partial volume. These findings suggest that high b-value DTI redundantly parallels with NODDI-based cortical neurite measures, but the conventional low b-value DTI is hard to reasonably characterize cortical microarchitecture

Capsaicin May Improve Swallowing Impairment in Patients with Amyotrophic Lateral Sclerosis: A Randomized Controlled Trial

Patients with neurodegenerative diseases are at an increased risk of dysphagia and aspiration pneumonia. In this study, we examined whether ingestion of capsaicin prior to swallowing changes the temporal dynamics of swallowing in such patients. In a crossover, randomized controlled trial, 29 patients with neurodegenerative diseases were given a soluble wafer containing 1.5 μg capsaicin or an identical placebo 20 min prior to testing. For evaluation with video fluoroscopy (VF), patients consumed a barium-containing liquid plus thickening material. The durations of the latency, elevating and recovery periods of the hyoid were assessed from VF. Overall, no significant differences were observed in the duration of each period between capsaicin and placebo treatments. However, reductions in the latency and elevating periods were positively correlated with baseline durations. In subgroup analyses, that correlation was observed in patents with amyotrophic lateral sclerosis (ALS) but not in patients with Parkinson’s disease. The consumption of wafer paper containing capsaicin before the intake of food may be effective in patients with dysphagia related with certain neurodegenerative diseases, particularly ALS patients. Further studies will be needed to validate this finding

Portable Electrochemical Sensing System Attached to Smartphones and Its Incorporation with Paper-based Electrochemical Glucose Sensor

This paper described the development of a small and low cost biosensor consisting of a smartphone-based electrochemical biosensor device and a paper-based biosensor. The device harvested power from the smartphone and transferred data through audio jack. We designed CMOS circuits including a power supply circuit, a potentiostat, and a ΔΣ modulator. The fabrication of a paper-based biosensor was simple: the three electrodes were directly drawn on chromatography paper using a carbon pencil. The paper-based biosensor was low cost, disposable, portable and friendly to the environment. The sensing system was designed to perform the chronoamperometry measurement, and the glucose concentration in a liquid specimen was detected. Results showed that the sensing system was capable of measuring the glucose concentration as precisely as expensive equipments

Seronegative Oligoarthritis Preceding Psoriasis by 9.5 Years

We report a case of psoriatic arthritis where oligoarthritis preceded the skin lesions. A 57-year-old man complained of left third-finger pain. Laboratory examinations were negative for anti-cyclic citrullinated peptide antibodies and rheumatoid factor; he was treated for suspected rheumatoid arthritis. Six years later, X-ray revealed enthesitis of his fingers and wrist joint. At 9.5 years after the initial visit, skin lesions appeared in the left auricular region and buttock and dermatopathology findings indicated psoriasis vulgaris. The final diagnosis was psoriatic arthritis. In cases of seronegative oligoarthritis, psoriatic arthritis must be considered because some patients demonstrate osteoarticular lesions preceding skin lesions

Big Three Dragons: A [N II] 122 μ\mum Constraint and New Dust-continuum Detection of A z=7.15z = 7.15 Bright Lyman Break Galaxy with ALMA

We present new Atacama Large Millimeter/submillimeter Array Band 7 observational results of a Lyman break galaxy at $z=7.15$, B14-65666 ("Big Three Dragons"), which is an object detected in [OIII] 88 $\rm{\mu m}$, [CII] 158 $\rm{\mu m}$, and dust-continuum emission during the epoch of reionization. Our targets are the [NII] 122 $\rm{\mu m}$ fine-structure emission line and underlying 120 $\rm{\mu m}$ dust continuum. The dust continuum is detected with a $\sim$19$\sigma$ significance. From far-infrared spectral energy distribution sampled at 90, 120, and 160 $\rm{\mu m}$, we obtaine a best-fit dust temperature of $40$ K ($79$ K) and an infrared luminosity of $\log_{10}(L_{\rm IR}/{\rm L}_\odot)=11.6$ ($12.1$) at the emissivity index $\beta = 2.0$ (1.0). The [NII] 122 $\rm{\mu m}$ line is not detected. The 3$\sigma$ upper limit of the [NII] luminosity is $8.1 \times 10^7\ {\rm L}_\odot$. From the [NII], [OIII], and [CII] line luminosities, we use the Cloudy photoionization code to estimate nebular parameters as functions of metallicity. If the metallicity of the galaxy is high ($Z > 0.4\ {\rm Z}_\odot$), the ionization parameter and hydrogen density are $\log_{10} U \simeq -2.7\pm0.1$ and $n_\text{H} \simeq 50$-$250\ {\rm cm}^{-3}$, respectively, which are comparable to those measured in low-redshift galaxies. The nitrogen-to-oxygen abundance ratio, $\rm{N/O}$, is constrained to be sub-solar. At $Z < 0.4\ {\rm Z}_\odot$, the allowed $U$ drastically increases as the assumed metallicity decreases. For high ionization parameters, the $\rm{N/O}$ constraint becomes weak. Finally, our Cloudy models predict the location of B14-65666 on the BPT diagram, thereby allowing a comparison with low-redshift galaxies.Comment: 17 pages, 13 figures, 2 tables. accepted for publication in Ap

Dynamics of light-induced anomalous Hall effect in the three-dimensional Dirac semimetal Cd3_3As2_2

We experimentally study the dynamical behavior of the light-induced anomalous Hall effect in a three-dimensional Dirac semimetal, Cd$_3$As$_2$. An ultrashort, circularly polarized, multi-terahertz pump pulse breaks the time-reversal symmetry of a thin film sample. The resulting anomalous Hall effect is clearly observed through the polarization rotation of a single-cycle terahertz probe pulse. Comparing the experimental result with theory, we find that the field-induced injection current dominates the anomalous Hall effect during pump irradiation, while the Berry curvature of the Floquet-Weyl semimetal state does not appreciably contribute. Remarkably, even after pump irradiation, we observe an anomalous Hall effect that lasts for more than 10 ps. A model fit to the Hall conductivity spectrum reveals a relatively long scattering time over 400 fs. This result shows that circularly polarized light creates a polarization of the isospin degree of freedom in the Dirac semimetal, which labels the crystallographic point group representation of the overlapping Weyl semimetal bands. Our observation paves the way for conversion of a robust isospin flow into an electric current at room temperature, being a new analogue of the inverse spin Hall effect.Comment: 44 pages, 14 figure