Thermoelectric effect in kagome lattice enhanced at van Hove singularities

We have performed first-principles calculations using density functional theory on a kagome lattice model with a chiral spin state, as a representative example demonstrating significant longitudinal and transverse thermoelectric properties. The results revealed that the saddle-point-type van Hove singularity (VHS) enhances thermoelectric effects. The longitudinal thermoelectric conductivity $\alpha_{xx}$ was large at the chemical potentials tuned close to the band at the symmetry points, K (lower band edge), $\Gamma$ (upper band edge), and M (saddle point), where the VHSs of the density of states (DOS) were at the corresponding band energies. The transverse thermoelectric conductivity $\alpha_{xy}$ was large at the chemical potential of saddle-point-type VHS. A large anomalous Nernst coefficient of about 10 $\mu$V/K at 50 K was expected

Large N Analysis of TTˉT\bar{T}-deformation and Unavoidable Negative-norm States

We study non-perturbative quantum aspects of $T\bar{T}$-deformation of a free $O(N)$ vector model by employing the large $N$ limit. It is shown that bound states of the original field appear and inevitably become negative-norm states. In particular, the bound states can be regarded as the states of the conformal mode in a gravitational theory, where the Liouville action is induced with the coefficient proportional to the minus of central charge. To make the theory positive-definite, some modification is required so as to preserve diffeomorphism invariance due to the Faddeev-Popov ghosts with a negative central charge.Comment: 1+20 pages, 1 figur

A simple calculation for the preoperative estimation of transverse rectus abdominis myocutaneous free flap volume in 2-stage breast reconstruction using a tissue expander

Background Flap volume is an important factor for obtaining satisfactory symmetry in breast reconstruction with a transverse rectus abdominis myocutaneous (TRAM) free flap. We aimed to develop an easy and simple method to estimate flap volume. Methods We performed a preoperative estimation of the TRAM flap volume in five patients with breast cancer who underwent 2-stage breast reconstruction following an immediate tissue expander operation after a simple mastectomy. We measured the height and width of each flap zone using a ruler and measured the tissue thickness by ultrasound. The volume of each zone, approximated as a triangular or square prism, was then calculated. The zone volumes were summed to obtain the total calculated volume of the TRAM flap. We then determined the width of zone II, so that the calculated flap volume was equal to the required flap volume (1.2×1.05×the weight of the resected mastectomy tissue). The TRAM flap was transferred vertically so that zone III was located on the upper side, and zone II was trimmed in the sitting position after vascular anastomosis. We compared the estimated flap width of zone II (=X) with the actual flap width of zone II. Results X was similar to the actual measured width. Accurate volume replacement with the TRAM flap resulted in good symmetry in all cases. Conclusions The volume of a free TRAM flap can be straightforwardly estimated preoperatively using the method presented here, with ultrasound, ruler, and simple calculations, and this technique may help reduced the time required for precise flap tailoring

Angular sway propagation in One Leg Stance and quiet stance with Inertial Measurement Units for older adults

Postural stability degrades with age, threating the health and life quality of the older adults. One Leg Stance (OLS) is one of the standard and commonly adopted assessments for postural stability, and the postural sway in OLS has been demonstrated to be related with age. The propagation of postural sway between body segments could be a hint to the underlying mechanism of balance control. However, it is not yet fully understood. Therefore, the aim of this paper was to study the angular sways and their propagation of the head, trunk, and lower limb in healthy older adults. A cross-correlation of the normalized angular speeds was performed and the experiment with 68 older adults was conducted. The results showed that the head, hip and ankle joints affected the transfer of angular sway with a relatively lower correlation and longer latency

Clinical studies on bronchial asthma induced by chironomid midges -comparison between positive and negative cases to house dust-

近年ユスリカが気管支喘息の原因抗原となり得ることが報告されている。しかし，その臨床的特徴はいまだ明らかにされていない。このユスリカ抗原の特徴を検討する目的で，気管支喘息症例163例をHD（ハウスダスト）に感作されたRAST　score2＋以上の陽性例82例とscore1＋以下の陰性例81例とに分けて比較検討を行なった。その結果皮膚反応，ヒスタミン遊離，CTT抗原を用いた特異的IgE抗体いずれの検討においても，HDに感作された症例が，よりユスリカ抗原にも感作されやすいことが明らかになった。In recent years it has been reported that chironomid migdes might be one of the causative allergens in bronchial asthma. In order to clarify the clinical characteristics of bronchial asthma induced by chironomid midges (Tokunagayusurika akamusi), 163 patients with bronchial asthma were studied. The subjects were divided into two groups ; cases with negative (0～1 + ) and positive (2 + or more) RAST score to house dust. 1. Skin reaction to midges was positive in 54 cases (33.1%) out of 163 patients with bronchial asthma. Thirty-six cases (43.9%) out of 82 asthmatics with positive RAST score to house dust showed positive skin reaction to midges, but in 81 cases with negative RAST score, only 18 cases (22.2%) showed positive skin reaction. 2. Fourteen cases out of 85 asthmatics showed a significant amount of histamine release (more than 15%).　A significant amount of histamine release was observed in 12 cases (23.5%) out of 51 cases with positive RAST score, but in only two cases (5.9%) out of 24 cases with negative RAST score. 3. Specific IgE antibodies to CTT (Chiromonus thummi thummi) was positive in 12 cases (18.2%) out of 66 asthmatics. In 41 asthmatics with positive RAST score to house dust, 12 cases (29.3%) showed positive RAST score to CTT, though in 25 cases with negative RAST score to house dust no cases showed positive RAST score to CTT. In conclusion, cases with house dust allergy were more easily sensitized by chironomid migdes than those cases without house dust allergy

Influx of nitrogen-rich material from the outer Solar System indicated by iron nitride in Ryugu samples

Large amounts of nitrogen compounds, such as ammonium salts, may be stored in icy bodies and comets, but the transport of these nitrogen-bearing solids into the near-Earth region is not well understood. Here, we report the discovery of iron nitride on magnetite grains from the surface of the near-Earth C-type carbonaceous asteroid Ryugu, suggesting inorganic nitrogen fixation. Micrometeoroid impacts and solar wind irradiation may have caused the selective loss of volatile species from major iron-bearing minerals to form the metallic iron. Iron nitride is a product of nitridation of the iron metal by impacts of micrometeoroids that have higher nitrogen contents than the CI chondrites. The impactors are probably primitive materials with origins in the nitrogen-rich reservoirs in the outer Solar System. Our observation implies that the amount of nitrogen available for planetary formation and prebiotic reactions in the inner Solar System is greater than previously recognized

Four‐dimensional‐STEM analysis of the phyllosilicate‐rich matrix of Ryugu samples

Ryugu asteroid grains brought back to the Earth by the Hayabusa2 space mission are pristine samples containing hydrated minerals and organic compounds. Here, we investigate the mineralogy of their phyllosilicate-rich matrix with four-dimensional scanning transmission electron microscopy (4D-STEM). We have identified and mapped the mineral phases at the nanometer scale (serpentine, smectite, pyrrhotite), observed the presence of Ni-bearing pyrrhotite, and identified the serpentine polymorph as lizardite, in agreement with the reported aqueous alteration history of Ryugu. Furthermore, we have mapped the d-spacings of smectite and observed a broad distribution of values, ranging from 1 to 2 nm, with an average d-spacing of 1.24 nm, indicating significant heterogeneity within the sample. Such d-spacing variability could be the result of either the presence of organic matter trapped in the interlayers or the influence of various geochemical conditions at the submicrometer scale, suggestive of a range of organic compounds and/or changes in smectite crystal chemistry