Topological Kagome Magnet Co3Sn2S2 Thin Flakes with High Electron Mobility and Large Anomalous Hall Effect.

Magnetic Weyl semimetals attract considerable interest not only for their topological quantum phenomena but also as an emerging materials class for realizing quantum anomalous Hall effect in the two-dimensional limit. A shandite compound Co3Sn2S2 with layered kagome-lattices is one such material, where vigorous efforts have been devoted to synthesize the two-dimensional crystal. Here, we report a synthesis of Co3Sn2S2 thin flakes with a thickness of 250 nm by chemical vapor transport method. We find that this facile bottom-up approach allows the formation of large-sized Co3Sn2S2 thin flakes of high-quality, where we identify the largest electron mobility (∼2600 cm2 V-1 s-1) among magnetic topological semimetals, as well as the large anomalous Hall conductivity (∼1400 Ω-1 cm-1) and anomalous Hall angle (∼32%) arising from the Berry curvature. Our study provides a viable platform for studying high-quality thin flakes of magnetic Weyl semimetal and stimulate further research on unexplored topological phenomena in the two-dimensional limit.

Giant magneto-optical responses in magnetic Weyl semimetal Co3Sn2S2.

The Weyl semimetal (WSM), which hosts pairs of Weyl points and accompanying Berry curvature in momentum space near Fermi level, is expected to exhibit novel electromagnetic phenomena. Although the large optical/electronic responses such as nonlinear optical effects and intrinsic anomalous Hall effect (AHE) have recently been demonstrated indeed, the conclusive evidence for their topological origins has remained elusive. Here, we report the gigantic magneto-optical (MO) response arising from the topological electronic structure with intense Berry curvature in magnetic WSM Co3Sn2S2. The low-energy MO spectroscopy and the first-principles calculation reveal that the interband transitions on the nodal rings connected to the Weyl points show the resonance of the optical Hall conductivity and give rise to the giant intrinsic AHE in dc limit. The terahertz Faraday and infrared Kerr rotations are found to be remarkably enhanced by these resonances with topological electronic structures, demonstrating the novel low-energy optical response inherent to the magnetic WSM.

Topological transitions among skyrmion- and hedgehog-lattice states in cubic chiral magnets.

Manipulating topological spin textures is a key for exploring unprecedented emergent electromagnetic phenomena. Whereas switching control of magnetic skyrmions, e.g., the transitions between a skyrmion-lattice phase and conventional magnetic orders, is intensively studied towards development of future memory device concepts, transitions among spin textures with different topological orders remain largely unexplored. Here we develop a series of chiral magnets MnSi1-xGex, serving as a platform for transitions among skyrmion- and hedgehog-lattice states. By neutron scattering, Lorentz transmission electron microscopy and high-field transport measurements, we observe three different topological spin textures with variation of the lattice constant controlled by Si/Ge substitution: two-dimensional skyrmion lattice in x = 0-0.25 and two distinct three-dimensional hedgehog lattices in x = 0.3-0.6 and x = 0.7-1. The emergence of various topological spin states in the chemical-pressure-controlled materials suggests a new route for direct manipulation of the spin-texture topology by facile mechanical methods.

Large magneto-thermopower in MnGe with topological spin texture.

Quantum states characterized by nontrivial topology produce interesting electrodynamics and versatile electronic functionalities. One source for such remarkable phenomena is emergent electromagnetic field, which is the outcome of interplay between topological spin structures with scalar spin chirality and conduction electrons. However, it has scarcely been exploited for emergent function related to heat-electricity conversion. Here we report an unusually enhanced thermopower by application of magnetic field in MnGe hosting topological spin textures. By considering all conceivable origins through quantitative investigations of electronic structures and properties, a possible origin of large magneto-thermopower is assigned to the strong energy dependence of charge-transport lifetime caused by unconventional carrier scattering via the dynamics of emergent magnetic field. Furthermore, high-magnetic-field measurements corroborate the presence of residual magnetic fluctuations even in the nominally ferromagnetic region, leading to a subsisting behavior of field-enhanced thermopower. The present finding may pave a way for thermoelectric function of topological magnets.

Lightning injury as a blast injury of skull, brain, and visceral lesions: clinical and experimental evidences.

The present study attempts to better understand the mechanism of injuries associated with direct lightning strikes. We reviewed the records of 256 individuals struck by lightning between 1965 and 1999, including 56 people who were killed. Basal skull fracture, intracranial haemorrhage, pulmonary haemorrhage, or solid organ rupture was suspected in three men who died. Generally these lesions have been attributed to current flow or falling after being struck. However, examination of surface injuries sustained suggested that the true cause was concussion secondary to blast injury resulting from vaporization of water on the body surface by a surface flashover spark. To investigate this hypothesis, an experimental model of a lightning strike was created in the rat. Saline-soaked blotting paper was used to simulate wet clothing or skin, and an artificial lightning impulse was applied. The resultant lesions were consistent with our hypothesis that the blast was reinforced by the concussive effect of water vaporization. The concordance between the clinical and experimental evidence argues strongly for blast injury as an important source of morbidity and mortality in lightning strikes.

Correlation between magnetic resonance imaging and histopathology of an amputated forearm after an electrical injury.

A 53-year-old man sustained a 50 Hz, 60 kV electrical injury. The current flowed between his right hand and both feet. There was necrosis of the distal portion of the right forearm, and the fourth and fifth toes on the right foot. The skin on the amputated right upper extremity appeared normal except for an ulcer in the antecubital fossa and some blister scars. However, most of the muscles of the arm at the elbow were necrosed and partially replaced by fatty tissue or fibrosis. These necrotic areas corresponded to minimally increased signal intensities on T1-weighted MRI, and high signal intensities on T2-weighted images. MRI may be employed to predict amputation level after electrical injury.

Preparation of needle-like hydroxyapatite by homogeneous precipitation under hydrothermal conditions.

Preparation of hydroxyapatite was carried out by a homogeneous precipitation technique using hydrothermal reactions of Ca(EDTA)2- and PO4(3-) at 130-250 degrees C and pH 4-10. Hydroxyapatite and monetite were formed above pH 6 and below pH 4, respectively. Needle-like hydroxyapatite was formed at high temperatures above 130 degrees C. The length of the needle-like hydroxyapatite crystal increased with increasing working solution pH and temperature.

[A Case of central venous catheter-related infection with Malassezia sympodialis].

We report a 63-year-old male with central venous catheter-related infection caused by Malassezia sympodialis after total gastrectomy for a gastric cancer. He had fever and his leukocyte counts and C-reactive protein were elevated 14 days after his operation. After his central venous hyperalimentation catheter was removed, the inflammatory signs immediately disappeared, suggesting an intravenous catheter-related infection. A yeast-like fungus was cultured in brain-heart infection semi-solid agar ten days later, and was diagnosed morphologically as Malassezia sp. This strain was identified as M. sympodialis by Tween assimilation test and was confirmed by whole-sequence of internal transcribed spacer 1 regions (ITS1). This is the first report of catheter-related infection caused by M. sympodialis. This strain grew and was subcultured on CHROMagar Candida, potato dextrose agar and Sabouraud agar. There have been no reports of such a lipid-independent Malassezia sp. except for M. pachydermatis. The mechanism of lipid independence of this strain is undetermined and future work is needed. Malassezia sp. is receiving increased attention as an etiologic pathogen of catheter-related fungemia in clinical microbiology laboratories and infectious disease sections.

Sclerotherapy of hydroceles with polidocanol.

Fifteen patients with hydroceles of the testis or spermatic cord were treated by aspiration and injection of the sclerosant solution polidocanol. The cure rate of hydroceles after one sclerotherapy session was 73%, and the overall cure rate using the procedure was 87%. No patient experienced pain during or after the procedure, which was conducted without anaesthesia. No complications were observed. It is concluded that sclerotherapy of hydroceles with polidocanol may be a useful alternative to open operation, due to its ease of administration, low frequency of complications, and high rate of effectiveness, and that this agent is preferable to certain other drugs in that it causes no pain during or after the injection.

Etoposide, epirubicin and carboplatin in hormone-refractory prostate cancer.

Twelve patients with hormone-refractory prostate cancer were treated with combination chemotherapy of etoposide, epirubicin and carboplatin (EEC). At relapse, all patients had metastases to the bone and/or soft tissues. The median number of courses was 3 (range 1-10). Epirubicin was not administered in 6 patients because of heart disease. Three patients (25%) had a partial response and 8 (67%) showed no change. The overall response rate was 92%. Pain relief was observed in 4 patients (44%). Four patients were still alive after a mean observation period of 18 months (range 4-36 months), while 8 died with a mean survival period of 11 months (range 7-15 months). Nausea, appetite loss, and alopecia were observed in some patients. All except one patient experienced bone marrow suppression, 5 of whom were treated with granulocyte-colony stimulating factor. EEC chemotherapy in hormone-refractory prostate cancer is considered to be more effective than other kinds of chemotherapy, whereas it frequently induces bone marrow suppression.

Cold crucible levitation melting of biomedical Ti-30 wt%Ta alloy.

Recently, titanium-tantalum alloys have been studied as implant materials for dental and orthopedic surgery. However, titanium and tantalum are difficult to mix by common arc melting and induction melting, because of their high melting point and the marked difference between their densities (Ti: 1,680 degrees C, 4.5 g/cm3, Ta: 2,990 degrees C, 16.6 g/cm3). Thus, the Cold Crucible Levitation Melting (CCLM) method was chosen to produce a Ti-30 wt%Ta binary alloy in the present study. The CCLM furnace, with 1 kg capacity, consisted of a water-cooled crucible comprising oxygen-free high purity copper segments and coils wrapped around the crucible and connected to a frequency inverter power supply. A qualified ingot of 1.0 kg of Ti-30 wt%Ta alloy was obtained. The ingot was characterized from the surface quality, chemical composition distribution and microstructure, and finally the melting process was discussed.

[Relationship between reactivation and tumor markers in prostatic cancer].

Twenty-seven cases of reactivated prostatic cancer between 1979 and 1990 were investigated. Reactivation took place in the form of local aggravation in 3 cases, occurrence or aggravation of metastasis to bones in 8 cases, and in both forms in 16 cases. The elevation of tumor markers preceded the clinical findings in 11 cases (41%). In 75% of the cases with occurrence or aggravation of metastasis, the elevation of tumor markers preceded the clinical findings. This showed that tumor markers were useful in most cases for early detection of reactivation. However, in 3 cases with local aggravation, the clinical findings preceded the elevation of tumor marks. Therefore, it is also important to check the clinical findings at the follow-up. At the time of reactivation, positive rates of prostatic acid phosphatase (PAP), gamma-seminoprotein (gamma-Sm) and prostatic specific antigen (PA) were 78%, 83% and 80%, respectively. Thus gamma-Sm and PA appeared to be more reliable than PAP for monitoring of prostatic cancer.

[Studies of transrectal prostatic ultrasonography on patients with male infertility].

The diagnostic significance of transrectal prostatic ultrasonography for chronic prostatitis and varicocele was evaluated in 380 male infertility patients. Of 20 patients with pyospermia, thought to be mainly caused by chronic prostatitis, 10.0 percent showed heterogeneous echo pattern of the prostate, while 25.0 percent showed capsular irregularity. Since 285 patients with non-infected semen showed similar sonographic findings, it is concluded that prostatic ultrasonography has little value in the diagnosis of chronic prostatitis in infertile patients. Enlarged periprostatic echo-free zone, thought to coincide with the dilatation of the Santrini's plexus, was found in 42.9 and 42.7 percent of patients with chronic prostatitis and varicocele, respectively, in contrast to 34.0 percent of patients without either diseases. Twelve percent of patients with varicocele showed highly enlarged echo-free zone, which was significantly more frequent compared to 5.0 percent in normal patients. Moreover, follow up of 4 patients with varicocele pre- and post-operatively found 2 of them to show a great improvement in the enlargement of the zone. These results suggest that varicocele may cause the dilation of the Santrini's plexus through a venous anastomosis in some patients and transrectal ultrasonography may be a useful tool in detecting small varicoceles in such patients.

[Intrapleural administration of CDDP against malignant pleural effusions in breast cancer].

Malignant pleural effusion in the patients with breast cancer commonly occurs, and is a life-threatening factor. The present paper shows the usefulness of intrapleural administration of CDDP in six cases. A decrease of pleural effusions was observed in all cases. Treatment was effective in two cases of CR and four cases of PR. A median survival from initiation of intrapleural therapy is 17 months (range 2-47 months). This procedure produced distinctly fewer side effects than intravenous administration. The results of this trials suggest that CDDP should be considered as an active agent in the treatment of malignant pleural effusion in the patients with breast cancer.

[Problems in multidisciplinary treatment from the standpoint of clinical characteristics in human cancers].

We investigated the amplification and expression of oncogenes in human gastric and breast cancers. The biological malignancy of the cases with oncogene amplification/expression was higher than that of the cases without amplification/expression. Moreover, the case with amplification/expression of oncogene was found to be highly correlated with distant organ metastasis. In strongly suggests the necessity of postoperative adjuvant therapy. In addition, these data will have to be taken into consideration as deciding on the way of operation and therapy.