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In a hybrid system of topological insulator (TI)/superconductor (SC), the proximity-induced topological superconductivity is expected to appear at the interface. Here we propose and demonstrate that a TI/SC hybrid Bi2Te3/PdTe2 heterostructure serves as a platform for exploring topological superconductivity with various features: all made of tellurium compounds, epitaxial growth, and a small charge transfer interface. In the Bi2Te3/PdTe2 heterostructure films, we observe large nonreciprocal charge transport near the superconducting transition temperature under a transverse in-plane magnetic field. The observation indicates the interplay between the topological surface state and superconductivity, suggesting that the Bi2Te3/PdTe2 heterostructure is a candidate for a topological superconductor. Also observed is an unexpected sign reversal of the nonreciprocal coefficient when the in-plane magnetic field is slightly tilted toward the out-of-plane direction. The analysis reveals that the sign reversal occurs with the change of dominant vortex type, that is, the change from spontaneous vortices to external-field induced ones.

The topological nature of the quantum anomalous Hall effect (QAHE) causes a dissipationless chiral edge current at the sample boundary1,2. Of fundamental interest is whether the chirality of the band structure manifests itself in charge transport properties. Here we report the observation of large non-reciprocal charge transport3 in a magnetic topological insulator, Cr-doped (Bi,Sb)2Te3. When the surface massive Dirac band is slightly carrier doped by a gate voltage, the edge state starts to dissipate and exhibits a current-direction-dependent resistance with a directional difference as large as 26%. The polarity of this diode effect depends on the magnetization direction as well as on the carrier type, electrons or holes. The correlation between the non-reciprocal resistance and the Hall resistance indicates that the non-reciprocity originates from the interplay between the chiral edge state and the Dirac surface state.

We have investigated the nonreciprocal electrical transport, that is a nonlinear resistance effect depending on the current direction, in multiferroic Rashba semiconductor (Ge,Mn)Te. Due to coexistence of ferromagnetic and ferroelectric orders, (Ge,Mn)Te provides a unique platform for exploring the nonreciprocal electrical transport in a bulk form. (Ge,Mn)Te thin films shows a large nonreciprocal resistance compared to GeTe, the nonmagnetic counterpart with the same crystal structure. The magnetic-field-angle dependence of the nonreciprocal resistance is maximized when magnetic field is orthogonal to both current and electric polarization, in accord with the symmetry argument. From the analysis of temperature and magnetic field dependence, we deduce that inelastic scatterings of electrons mediated by magnons dominantly contribute to the observed nonreciprocal response. Furthermore, the nonreciprocal resistance is significantly enhanced by lowering hole density. The Fermi level dependence is attributed to the deformation of the Rashba band in which the spin-momentum locked single Fermi surface appears by exchange field from the in-plane magnetization. The present study provides a key insight to the mechanisms of novel transport phenomena caused by the interplay of ferroelectric and ferromagnetic orders in a semiconductor.

We report experimental signatures of topological transitions among the Weyl semimetal states of pyrochlore Pr2Ir2O7, where the Kondo coupling between the Ir topological electrons and the spin-ice like orders of Pr moments plays a decisive role. The magnetic-field dependence of resistivity and the Hall conductivity exhibits a plateau and a sharp jump associated with a magnetic-field hysteresis, similar to a liquid-gas-like transition in dipolar spin ice system. Furthermore, the Kondo coupling is controlled by the hydrostatic pressure, revealing that the field-induced displacement of Weyl points in the momentum space strongly depends on the respective electronic state as well as on the Kondo coupling strength. These observations pave a route toward the engineering of band topology in hybrid quantum materials with relativistic conduction electrons and localized magnetic moments.

Recently, emulation of topological states based on electrical circuits draws much attention in view of future quantum computing. We have demonstrated a topological phase transition by switching a step-variable-resettable SOI-MEMS capacitor for the first time. The circuit shows significantly different responses for the topological and trivial phases of the Su-Schrieffer-Heeger (SSH) model by switching the capacitance. We have fabricated a mechanical latching structure integrated with comb capacitors to realize such a MEMS variable capacitance. Our device will open a new field called “topological MEMS (TopoMEMS) circuit”.

We report a systematic study on the growth conditions of ${\mathrm{Sn}}_{1\text{\ensuremath{-}}x}{\mathrm{In}}_{x}\mathrm{Te}$ thin films by molecular beam epitaxy for maximization of superconducting transition temperature ${T}_{\mathrm{c}}$. Careful tuning of the flux ratios of Sn, In, and Te enables us to find an optimum condition for substituting rich In content $(x=0.66)$ into the Sn site in a single phase of ${\mathrm{Sn}}_{1\text{\ensuremath{-}}x}{\mathrm{In}}_{x}\mathrm{Te}$ beyond the bulk solubility limit at ambient pressure $(x=0.5)$. ${T}_{\mathrm{c}}$ shows a dome-shaped dependence on In content $x$ with the highest ${T}_{\mathrm{c}}=4.20\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ at $x=0.55$, being consistent to that reported for bulk crystals. The well-regulated ${\mathrm{Sn}}_{1\text{\ensuremath{-}}x}{\mathrm{In}}_{x}\mathrm{Te}$ films can be a useful platform to study possible topological superconductivity by integrating them into the state-of-the-art junctions and/or proximity-coupled devices.

Superconductivity in the doped topological crystalline insulator ${\mathrm{Sn}}_{1\ensuremath{-}x}{\mathrm{In}}_{x}\mathrm{Te}$ is studied by first-principles calculation based on superconducting density functional theory (SCDFT) and tunneling spectroscopy. By considering the spin-orbit coupling and frequency dependence of the screened Coulomb interaction in SCDFT, we succeed in reproducing the critical temperature of ${\mathrm{Sn}}_{1\ensuremath{-}x}{\mathrm{In}}_{x}\mathrm{Te}$ quantitatively, in which the spin-orbit coupling is found to play an essential role. The leading gap function is a conventional $s$ wave with moderate anisotropy in $\mathbit{k}$ space, and we find that the subdominant odd-parity instability is significantly weaker than the $s$-wave instability. We perform tunneling spectroscopy measurement and confirm that the spectrum is consistent with the calculated gap function.

We have studied the fundamental properties of weak-link ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}/{\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ Josephson junctions fabricated by making a narrow constriction on superconducting ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ films through laser micropatterning. The junctions show a typical overdamped behavior with much higher critical current density compared with those previously reported for bulk ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}/s$-wave-superconductor junctions. Observed magnetic-field and temperature dependencies of the Josephson critical current suggest that the chiral $p$ wave is unlikely for the superconducting symmetry, encouraging further theoretical calculations of the ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}/{\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$-type junctions.

We report a current scaling study of a quantum phase transition between a quantum anomalous Hall insulator and a trivial insulator on the surface of a heterostructure film of magnetic topological insulators. The transition was observed by tilting the magnetization while measuring the Hall conductivity $\sigma_{xy}$. The transition curves of $\sigma_{xy}$ taken under various excitation currents cross each other at a single point, exemplifying a quantum critical behavior of the transition. The slopes of the transition curves follow a power law dependence of the excitation current, giving a scaling exponent. Combining with the result of the previous temperature scaling study, critical exponents $\nu$ for the localization length and $p$ for the coherence length are separately evaluated as $\nu$ = 2.8 $\pm$ 0.3 and $p$ = 3.3 $\pm$ 0.3., Comment: 6 pages, 4 figures

Aims Neurotropin® (NTP), an analgesic for chronic pain, has antihyperalgesic effects in specific alternation of rhythm in temperature (SART)-stressed rats. Previous studies have shown that SART stress induces hyperalgesia, as well as post-translational modification of proteins (including substrates for calpain, a calcium-dependent cysteine protease) in the mesencephalon of rats. To better understand the mechanism of action of NTP, we investigated whether SART stress activates calpain in the mesencephalon of rats and whether NTP inhibits this activation. Main methods Wistar rats were exposed to SART stress for 5 days. NTP (200 NU/kg/day) was administered intraperitoneally every day from the onset of SART stress. The mechanical pain threshold was measured using the Randall-Selitto test on the 6th day. Thereafter, the rat mesencephalon was immediately collected and calpain activity was examined using western blot analysis with a calpain cleavage site-specific antibody. Key findings SART stress induced hyperalgesia and increased the calpain activity in the mesencephalon of rats. In contrast, NTP treatment attenuated the hyperalgesia and prevented the increase in calpain activity in the mesencephalon of SART-stressed rats. Interestingly, a negative correlation was identified between calpain activity and mechanical pain threshold in SART-stressed rats treated with or without NTP. Furthermore, NTP inhibited calpain activity on mammalian uncoordinated-18 in rat mesencephalon homogenate and Ac-LLY-AFC as substrates in an in vitro cell-free system. Significance Our data demonstrate that NTP treatment prevents SART stress-induced calpain activation in the mesencephalon of rats and suggests that NTP-mediated antihyperalgesia is associated with an inhibition of calpain activity in the mesencephalon.

The impact of electron correlation on the Dirac semimetal state is investigated for perovskite ${\text{CaIrO}}_{3}$ in terms of the magnetotransport properties under varying pressures. The reduction of electron correlation with a pressure of 1 GPa enhances the Fermi velocity as much as 40%, but it reduces the mobility by an order of magnitude by detuning the Dirac node from the Fermi energy. Moreover, the giant magnetoresistance at the quantum limit due to the one-dimensional confinement of Dirac electrons is critically suppressed under pressure. These results indicate that the electron correlation is a crucial knob for controlling the transport of a correlated Dirac semimetal.

Quantum-relativistic materials often host electronic phenomena with exotic spatial distributions. In particular, quantum anomalous Hall (QAH) insulators feature topological boundary currents whose chirality is determined by the magnetization orientation. However, understanding the microscopic nature of edge vs. bulk currents has remained a challenge due to the emergence of multidomain states at the phase transitions. Here we use microwave impedance microscopy (MIM) to directly image chiral edge currents and phase transitions in a magnetic topological insulator. Our images reveal a dramatic change in the edge state structure and an unexpected microwave response at the topological phase transition between the Chern number [Formula: see text] and [Formula: see text] states, consistent with the emergence of an insulating [Formula: see text] state. The magnetic transition width is independent of film thickness, but the transition pattern is distinct in differently initiated field sweeps. This behavior suggests that the [Formula: see text] state has 2 surface states with Hall conductivities of [Formula: see text] but with opposite signs.

We report large enhancement of upper critical field ${H}_{\mathrm{c}2}$ observed in superconducting ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ thin films. Through dimensional crossover approaching two dimensions, ${H}_{\mathrm{c}2}$ except the in-plane field direction is dramatically enhanced compared to bulks, following a definite relation distinct from bulk one between ${H}_{\mathrm{c}2}$ and the transition temperature. The anomalous enhancement of ${H}_{\mathrm{c}2}$ is highly suggestive of important changes of the superconducting properties, possibly accompanied with rotation of the triplet $d$ vector. Our findings will become a crucial step to further explore exotic properties by employing ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ thin films.

The accuracy of Hall resistance in the quantum anomalous Hall effect has been studied at zero magnetic field using Crx(Bi,Sb) 2 − x Te3-based magnetic heterostructure films of topological insulators. The measured deviation of the Hall resistance from its theoretical value h / e 2 was less than 2 ppm when the source drain current was 30 nA. This result has verified that the quantization of the Hall resistance is very accurate in the magnetic heterostructure films and in the previously reported uniformly doped films.

We theoretically investigate the dynamical nuclear spin polarization in a quantum point contact (QPC) at finite magnetic field. We find that when the QPC is tuned to be spin selective, at the conductance of e^2/h, a finite bias induces a dipole-like (spatially anti-symmetric) nuclear polarization: at the QPC center the polarization is zero, while, for GaAs parameters, the nuclear spins down (up) are induced on the source (drain) side. We predict that the dipole-like polarization pattern can be distinguished from a uniform polarization due to a qualitatively different response of the QPC conductance to the NMR field., Comment: 17 pages, 8 figures; referees' comments incorporated, some typos corrected, footnotes' format changed

Objective Although the daily urinary sodium excretion (UNaV) is considered to provide the most reliable estimate of the daily sodium intake, it may be affected by salt loss due to sweating in summer. However, the seasonal variation in the daily UNaV associated with a normal lifestyle is unknown. Methods This study was performed in 348 outpatients from the Morioka region during three seasons: summer (summer 1), winter, and the following summer (summer 2). The daily UNaV (g salt/day) was estimated by the second morning urine method three times during each season. Seasonal variation was defined as a significant trend across the three seasons together with a significant difference between winter and both summers. Results In women, the daily UNaV was higher in winter (11.8±3.0 g salt/day) than in summer 1 (11.2±2.9 g salt/day) or summer 2 (11.0±2.9 g salt/day). In contrast, there was no marked seasonal variation in men. An analysis stratified by age (4 quartiles) identified seasonal variation in the older 2 quartiles of women (aged ≥68 years). In these women, the mean seasonal difference in the daily UNaV was 0.9 g of salt/day for both winter vs. summer 1 and winter vs. summer 2, while it was 0.1-0.8 g of salt/day in the other groups. Conclusion Seasonal variation in the daily UNaV only occurred in older female patients and was relatively small. This is evidence for restricting salt intake throughout the year and should reassure patients who are anxious about salt loss due to sweating in summer.

Gigantic magnetoresistance is shown in a Cr- and V-doped topological insulator multilayer, assuring robust axion insulator., Exploration of novel electromagnetic phenomena is a subject of great interest in topological quantum materials. One of the unprecedented effects to be experimentally verified is the topological magnetoelectric (TME) effect originating from an unusual coupling of electric and magnetic fields in materials. A magnetic heterostructure of topological insulator (TI) hosts such exotic magnetoelectric coupling and can be expected to realize the TME effect as an axion insulator. We designed a magnetic TI with a tricolor structure where a nonmagnetic layer of (Bi, Sb)2Te3 is sandwiched by a soft ferromagnetic Cr-doped (Bi, Sb)2Te3 and a hard ferromagnetic V-doped (Bi, Sb)2Te3. Accompanied by the quantum anomalous Hall (QAH) effect, we observe zero Hall conductivity plateaus, which are a hallmark of the axion insulator state, in a wide range of magnetic fields between the coercive fields of Cr- and V-doped layers. The resistance of the axion insulator state reaches as high as 109 ohms, leading to a gigantic magnetoresistance ratio exceeding 10,000,000% upon the transition from the QAH state. The tricolor structure of the TI may not only be an ideal arena for the topologically distinct phenomena but can also provide magnetoresistive applications for advancing dissipation-less topological electronics.

The quantum anomalous Hall effect (QAHE) is an exotic quantum phenomenon originating from dissipation-less chiral channels at the sample edge. While the QAHE has been observed in magnetically doped topological insulators (TIs), exploiting magnetic proximity effect on the TI surface from adjacent ferromagnet layers may provide an alternative approach to the QAHE by opening an exchange gap with less disorder than that in the doped system. Nevertheless, the engineering of a favorable heterointerface that realizes the QAHE based on the magnetic proximity effect remains to be achieved. Here, we report on the observation of the QAHE in a proximity coupled system of non-magnetic TI and ferromagnetic insulator (FMI). We have designed sandwich heterostructures of (Zn,Cr)Te/(Bi,Sb)2Te3/(Zn,Cr)Te that fulfills two prerequisites for the emergence of the QAHE; the formation of a sizable exchange gap at the TI surface state and the tuning of the Fermi energy into the exchange gap. The efficient proximity coupling in the all-telluride based heterostructure as demonstrated here will enable a realistic design of versatile tailor-made topological materials coupled with ferromagnetism, ferroelectricity, superconductivity, and so on., 18 pages, 4 figures

Salt-reduction guidance to hypertensive patients should be performed by evaluating salt intake of the individuals. However, each method to assess salt intake has both merits and limitations. Therefore, evaluation methods must be selected in accordance with the subject and facility's environment. In special facilities for hypertension treatment, measurement of sodium (Na) excretion with 24-h pooled urine or a survey on dietary contents by dietitians is recommended. In medical facilities in general, measurement of the levels of Na and creatinine (Cr) using second urine samples after waking-up or spot urine samples is recommended. The reliability of this method improves by using formulae including a formula to estimate 24-h Cr excretion. A method to estimate salt intake based on the Na excretion per gram Cr using the Na/Cr ratio in spot urine is simple, but not reliable. The method to estimate the daily excretion of salt from nighttime urine using an electronic salt sensor installed with a formula is recommended to hypertensive patients. Although its reliability is not high, patients themselves can measure this parameter simply at home and thus useful for monitoring salt intake and may intensify consciousness regarding salt reduction. Using these methods, salt intake (excretion) should be evaluated, and salt-reduction guidance targeting6 g (Na: 100 mmol) per day should be conducted in the management of hypertension.

Dietary salt consumption is closely associated with the level of blood pressure (BP); stricter salt reduction more markedly decreased BP. Obesity/metabolic syndrome, Dietary Approach to Stop Hypertension (DASH) diet, exercise and mental stress influence the BP-elevating effect of high-salt diet. Observational and intervention studies suggested that salt restriction improved the risk of cardiovascular diseases. However, the effects may differ among the types of the hypertensive complications; salt reduction may decrease the risk of stroke more than that of ischemic heart disease. Small-scale studies demonstrated that excess salt increased the risk of the left ventricular hypertrophy, heart failure, the urinary protein/albumin levels and end-stage renal failure. These diverse beneficial effects of salt reduction are probably because low-salt diet is an effective strategy to decrease BP and body fluid volume but is less effective to ameliorate the other cardiovascular risk factors. A mean salt intake in Japan is markedly high. Considering the present condition, salt reduction is essential for the prevention and treatment of hypertension and for the prevention of cardiovascular diseases.

In this section of the Report of the Salt Reduction Committee of the Japanese Society of Hypertension, the target level of dietary salt reduction and its scientific evidence, present status of salt consumption in Japan, salt-reducing measures/guidance methods in individuals and population strategies to reduce salt intake are introduced. In the Dietary Reference Intake for the general population in Japan (2010 version), the target levels of salt restriction in men and women were established as less than 9.0 per day and 7.5 g per day, respectively. The Japanese Society of Hypertension Guidelines for the Management of Hypertension 2009 recommended the target level of dietary salt restriction in patients with hypertension as less than 6 g per day. However, the National Health and Nutrition Survey of Japan in 2010 reported that the mean salt intake in adults was 10.6 g per day (men: 11.4 g per day and women: 9.8 g per day). To effectively decrease salt intake in Japan, it is necessary to reduce the consumption of high-salt foods (especially traditional foods) and replace high-salt seasonings (soy sauce and so on) with low-salt alternatives. Health-care professionals must effectively perform salt-reduction guidance for hypertensive patients in hospitals/administrative organizations. To promote population strategies for salt reduction in the whole society of Japan, social strategies, such as administrative policies, companies' cooperation and educational staff's cooperation, are necessary.

Aims In this study, we investigated the combined effect of Neurotropin® and pregabalin for L5-spinal nerve ligation (L5-SNL) model in rats and thiopental-induced sleep in mice. Main methods The left fifth lumbar nerve of rats was tightly ligated with silk sutures under pentobarbital anesthesia. The hindpaw withdrawal threshold was measured by application of von Frey filaments. Thiopental sodium was intravenously administered in mice and sleeping time was measured. In L5-SNL rats, an isobolographic analysis was performed to clarify the combined antiallodynic effect of Neurotropin and pregabalin 14 days after ligation in rats. In isobolographic analysis and thiopental-induced sleep test, Neurotropin and pregabalin were orally administered to coincide with the timing of the peak effect of each drug. Key findings Neurotropin (50–200 NU/kg) and pregabalin (2.5–10 mg/kg) showed a dose-dependent antiallodynic action in L5-SNL rats. The antiallodynic effect of pregabalin was reversed by intrathecal injection of yohimbine or ondansetron. Isobolographic analysis suggested that the combined antiallodynic effect of Neurotropin and pregabalin in L5-SNL rats may have been more than a mere additive effect. Neurotropin (50–400 NU/kg) had no effect on thiopental-induced sleeping time whereas pregabalin (30–100 mg/kg) significantly prolonged it. When the dose of pregabalin was 30 mg/kg, Neurotropin (50–400 NU/kg) did not further exacerbate the prolongation effect of pregabalin on thiopental-induced sleep. Significance It was suggested that when Neurotropin was administered in combination with pregabalin, it might provide more effective pain relief than that obtained with each agent alone in neuropathic pain without aggravating adverse effects of pregabalin.

OBJECTIVE To investigate the seasonal variation of severe hypoglycemia in hospitalized elderly patients. METHODS Among the patients hospitalized in our department between 2004 and 2010, we analyzed the records of 67 patients who required emergency admission for severe hypoglycemia and were aged 60 years or older. Comparisons were made between those admitted during the warm season (April-September) and those in the cold season (October-March). PATIENTS The mean age of the 67 patients was 76±8 years, including 45 men and 22 women. Twenty-four patients were admitted in the warm season and 43 patients were admitted in the cold season, with the average annual number being 3.4±1.9 and 6.1±2.8, respectively (p

The axion insulator which may exhibit an exotic quantized magnetoelectric effect is one of the most interesting quantum phases predicted for the three-dimensional topological insulator (TI). The axion insulator state is expected to show up in magnetically doped TIs with magnetizations pointing inwards and outwards from the respective surfaces. Towards the realization of the axion insulator, we here engineered a TI heterostructure in which magnetic ions (Cr) are modulation-doped only in the vicinity of the top and bottom surfaces of the TI ((Bi,Sb)

We report on emergence of two-dimensional conduction and ferromagnetism at the interface of MnTe thin films and InP substrates. The MnTe/InP heterostructures grown by molecular-beam epitaxy show thickness-independent sheet conductivity above a critical thickness of about 20 nm, indicating the formation of a conducting layer at the interface. Furthermore, the ferromagnetic behavior is confirmed by both magnetization and anomalous Hall effect measurements below a critical temperature of 270 K. The critical temperature is also independent of the thickness. By the investigation of the atomic structure with transmission electron microscopy, we observe a structural anomaly near the interface which consists of an antiprism-type Mn network unlike a prism-type Mn network of conventional MnTe. The band structure calculation shows that the antiprism-type MnTe can host metallic conduction and ferromagnetism, which is consistent with the present experimental results. The interface engineering based on the chalcogenide compound will develop a new arena for designing the emergent low dimensional conduction and magnetism.

The second morning urine (SMU) method was developed to evaluate daily salt intake, but the posture that should be adopted until the SMU collection remains unclear. This study investigated the influence of posture in hypertensive patients who underwent this test. The subjects were 100 patients who could collect 24-h urine samples correctly and were on a diet containing 7 g of salt per day. Their daily salt intake was estimated for three consecutive days in the recumbent, sitting, and sitting and standing positions (one posture each day). Estimated salt intake in the recumbent position (10.9+/-2.4 g day(-1)) was higher than in the sitting position (7.5+/-2.0 g day(-1)) and the sitting and standing position (6.3+/-1.7 g day(-1)). The salt intake estimated in the sitting and standing position was similar to that obtained by 24-h urine collection (6.3+/-1.6 g day(-1)) and was significantly (r=0.44, P0.05) correlated with the 24-h urine value. The actual difference in estimated salt intake between the two methods was 0.0+/-1.7 g day(-1). There were no significant differences in estimated salt intake between the two methods in patients taking different classes of antihypertensive drugs. In conclusion, adopting the sitting and standing position until the SMU collection is important for the correct estimation of daily salt intake, and this method could replace the 24-h collection method because of its convenience, especially in outpatients.

The helical Dirac fermions on the surface of topological insulators host novel relativistic quantum phenomena in solids. Manipulating spins of topological surface state (TSS) represents an essential step towards exploring the theoretically predicted exotic states related to time reversal symmetry (TRS) breaking via magnetism or magnetic field. Understanding Zeeman effect of TSS and determining its g-factor are pivotal for such manipulations in the latter form of TRS breaking. Here, we report those direct experimental observations in Bi2Se3 and Sb2Te2Se by spectroscopic imaging scanning tunneling microscopy. The Zeeman shifting of zero mode Landau level is identified unambiguously by judiciously excluding the extrinsic influences associated with the non-linearity in the TSS band dispersion and the spatially varying potential. The g-factors of TSS in Bi2Se3 and Sb2Te2Se are determined to be 18 and -6, respectively. This remarkable material dependence opens a new route to control the spins in the TSS., main text: 17 pages, 4 figures; supplementary: 15 pages, 7 figures

We have investigated the magnetic field and temperature dependence of the tunneling spectra of the eutectic system Sr2RuO4-Ru. Electric contacts to individual Ru lamellae embedded in Sr2RuO4 enable the tunneling spectra at the interface between ruthenate and a Ru microinclusion to be measured. A zero bias conductance peak (ZBCP) was observed in the bias voltage dependence of the differential conductance, suggesting that Andreev bound states are present at the interface. The ZBCP starts to appear at a temperature well below the superconducting transition temperature. The onset magnetic field of the ZBCP is also considerably smaller than the upper critical field when the magnetic field is parallel to the ab-plane. We propose that the difference between the onset of the ZBCP and the onset of superconductivity can be understood in terms of the existence of the single-component state predicted by Sigrist and Monien., Comment: 4 pages, 4 figures, to appear in J. Phys. Soc. Jpn. vol. 74 no. 2

Neurotropin®, a non-protein extract from the inflamed skin of rabbits inoculated with vaccinia virus, has been clinically used as an analgesic drug for treatment of chronic pain. In this study, we investigated the analgesic mechanisms of Neurotropin in the adjuvant-induced arthritic rat, a chronic pain model with inflammation. Neurotropin caused dose-dependent inhibition of hyperalgesia in the adjuvant-induced arthritic rat after single intravenous (10 – 100 NU/kg) and oral (30 – 200 NU/kg) administration. The analgesic effect of Neurotropin (intravenous 100 NU/kg and oral 200 NU/kg) was significantly inhibited by intrathecal injections of the α2-adrenoceptor antagonist yohimbine (30 nmol/animal) and the selective 5-HT3 serotonin receptor antagonist MDL72222 (30 nmol/animal), and slightly inhibited by the non-selective serotonin receptor antagonist methysergide (100 nmol/animal). The results suggest that the analgesic action of Neurotropin is at least in part due to the enhancement of noradrenergic and serotonergic descending pain inhibitory pathways. Neurotropin may be useful for the clinical management of chronic pain diseases such as a rheumatoid arthritis and osteoarthritis. Keywords:: Neurotropin, adjuvant-induced arthritis, descending pain inhibitory pathway, serotonin receptor, α2-adrenoceptor

A 46-year-old woman was presented with mineralocorticoid excess syndrome and a large mass originating from the right adrenal gland. Clinical examination before right adrenalectomy revealed elevated serum concentrations of 18-hydroxy-11-deoxycorticosterone (18-OH-DOC) both systemically and in the adrenal veins bilaterally. Histopathological and immunohistochemical analyses of the surgical specimen demonstrated adrenal hyperplasia of outer fasciculata cells, and the presence of cystic mass. The adrenalectomy ameliorated her blood pressure (BP) from 156/96 mmHg to 148/87 mmHg with a concomitant increase of serum potassium concentration from 3.1 mEq/l to 3.5 mEq/l. These results suggest that uni-adrenalectomy is, at least in part, effective in ameliorating not only BP but also potassium concentration in a patient of adrenal hyperplasia with excessive bilateral 18-OH-DOC production.

We investigated a superconductor–semiconductor–superconductor junction formed by two superconducting NbN electrodes and a two-dimensional electron gas (2DEG) in an AlGaAs/GaAs heterostructure. We obtained a good ohmic contact between NbN/AuGeNi electrodes and 2DEG by annealing them at 450°C for 1 min in an N2 atmosphere. We observed a decrease in the resistance caused by Andreev reflection (AR) within the superconducting energy gap voltage in a zero magnetic field in this structure. We found that the peculiar features of the magnetoresistance in the transition region can be qualitatively explained by considering the existence of the AR in high magnetic fields.

Aims Although the clinical use of Neurotropin ® as an analgesic for chronic pain has been firmly established, its analgesic mechanism is still unclear. In this study, we investigate the direct effects of Neurotropin using an electrophysiological method. Main methods Blind patch-clamp recordings were made from rat locus coeruleus (LC) and periaqueductal gray (PAG) neurons in brainstem slices of normal rats. The effects of intracerebroventricular (icv) injection of Neurotropin on nociceptive transmission were recorded from spinal substantia gelatinosa (SG) neurons in fifth lumbar spinal nerve-ligated (L5-SNL) rats using an in vivo patch-clamp method. Key findings Neurotropin (0.2–1.0 NU/mL) dose-dependently increased the firing rate in noradrenergic LC neurons of normal rats. Under the voltage-clamp condition, Neurotropin induced an inward current in 90% of LC neurons that was not affected by tetrodotoxin or an injection of GDP-β-S (G protein inhibitor) through recording pipettes. In contrast, Neurotropin had no effects on all PAG neurons tested. Using in vivo patch-clamp recordings, the icv injection of Neurotropin inhibited both frequency and amplitude of pinch-evoked excitatory postsynaptic currents of SG neurons in L5-SNL rats. These results suggest that Neurotropin directly excites the descending noradrenergic LC neurons and inhibits nociceptive transmission in the spinal dorsal horn. Significance This study is the first direct demonstration that Neurotropin activates the noradrenergic descending pain inhibitory systems, and this would reinforce the usefulness of Neurotropin in the treatment of human neuropathic pain.

Estimation of salt intake by cumbersome 24-h urine collection is not suitable for individual patients because of substantial daily variation in intake. We developed the second morning urine (SMU) method for monitoring daily salt intake in healthy subjects by calculating the daily creatinine excretion and measuring the ratio of sodium to creatinine in the SMU specimen. To determine whether the SMU method was applicable to hypertensive patients, we tested it in hospitalized patients under an equilibrated sodium balance as a model population. This review focuses on application of the SMU method in hypertensive patients with mild target organ damage.

Massless Dirac electrons in condensed matter have attracted considerable attention. Unlike conventional electrons, Dirac electrons are described in the form of two-component wave functions. In the surface state of topological insulators, these two components are associated with the spin degrees of freedom, hence governing the magnetic properties. Therefore, the observation of the two-component wave function provides a useful clue for exploring the novel spin phenomena. Here we show that the two-component nature is manifested in the Landau levels (LLs) whose degeneracy is lifted by a Coulomb potential. Using spectroscopic-imaging scanning tunneling microscopy, we visualize energy and spatial structures of LLs in a topological insulator Bi2Se3. The observed potential-induced LL splitting and internal structures of Landau orbits are distinct from those in a conventional electron system and are well reproduced by a two-component model Dirac Hamiltonian. Our model further predicts non-trivial energy-dependent spin-magnetization textures in a potential variation. This provides a way to manipulate spins in the topological surface state., Comment: Revised version to appear in Nature Physics. Supplementary information is available at http://www.riken.jp/epmrt/Hanaguri/SI/Bi2Se3_2comp/SI.html

SUMMARY 1. Few studies have been reported concerning the effect of ageing on renal functional and vascular responses to various stresses during ordinary life. In the present study, we examined the effect of age on changes in renal sodium handling and renal vascular resistance (RVR) in response to standing from a supine position in subjects with normal renal function. 2. We selected 43 healthy males in the second through to the seventh decade of life and gave them a constant dietary sodium intake before the study period. Renal function was estimated by standard clearance methods with the subject in a state of euvolaemia. 3. The mean daily urinary excretion of sodium was 236 ± 22 mEq. Standing from a supine position was associated with significant decreases (P < 0.0001) in creatinine clearance (from 125 ± 18 to 117 ± 19 mL/min per 1.73 m2), sodium excretion (from 178 ± 29 to 97 ± 23 μEq/min) and fractional excretion of sodium (from 1.02 ± 0.19 to 0.60 ± 0.13%). A significant increase (P < 0.0001) in the RVR index (from 0.11 ± 0.03 to 0.14 ± 0.04 units) was noted. Univariate analysis indicated that while the change in RVR associated with standing was significantly diminished (P < 0.05) in older subjects, orthostatic changes in other parameters associated with standing were minimally influenced by age. 4. In conclusion, although the renal vascular response is impaired in advanced age, the renal functional response to orthostasis is otherwise maintained in healthy elderly subjects under conditions of normal sodium intake and clinical euvolaemia.

Two-dimensional electron gas (2DEG) subjected to a spatially modulated magnetic field exhibits commensurability oscillation of magnetoresistance, analysis of which furnishes information on the modulation amplitude. Under a periodically modulated magnetic field with zero mean, the resistivity of the 2DEG gains an extra term expressed as Δρ=AT2+C. The temperature quadratic term is attributed to electron–electron umklapp scattering, while the constant term arises from combined effect of the lateral magnetic superlattice and random impurities. In the composite Fermion (CF) regime near the half-filling of lowest Landau levels, spatial variation of the electron density is equivalent to magnetic field variation. Use of a short period lateral superlattice has enabled us to observe the commensurability oscillation of the magnetoresistance of CFs near the filling factor ν=3/2. The positions of the resistance minima are consistent with those calculated by assuming magnetic modulation and fully spin-polarized CFs.

The vertical transport in multilayered quantum Hall systems has been studied under a tilted magnetic field. The out-of-plane resistance peaks at integer filling, and the peak value increases with increasing in-plane field component. The magnitude of the effect is almost the same in the low temperature regime and high temperature regime, and the effect can be accounted for by the suppression of the interlayer charge transfer by the in-plane field.

A 58-year-old woman was admitted to our hospital because of renal dysfunction that continued to progress even after withdrawal of cefdinir, the presumed cause of acute renal failure. Renal histologic findings included interstitial fibrosis accompanied by moderate lymphocytic infiltration, and tubular atrophy with reduced numbers of epithelial cells. Mesangial cells and glomerular basement membranes were nearly normal. Scintigraphy with 67gallium disclosed diffuse abnormal accumulation in both kidneys. A lymphocyte stimulation test with cefdinir was positive. The patient was diagnosed with acute tubulointerstitial nephritis caused by cefdinir. Serum creatinine concentrations continued to rise after withdrawal of the drug, but steroid therapy was effective in normalizing renal function.

A case of 46, XY pure gonadal dysgenesis with very tall stature was investigated. The 24-year-old, phenotypically female patient consulted our clinic because of linear growth persisting into adulthood. The patient was found to have no mutation or deletion of a sex-determining region of the Y chromosome, and also was found to have Graves' disease. Growth was arrested with height remaining at 187 cm after normalization of the thyroid function by treatment with an antithyroid agent, although follow-up to monitor growth was limited to 3 months. In some cases of gonadal dysgenesis, then, Graves' disease may contribute to an abnormally tall stature.

The vertical transport in weakly coupled multilayered two-dimensional electron systems has been studied in the integer quantum Hall regime. The current–voltage characteristics show prominent non-ohmicity in the vertical transport when each layer is in the quantum Hall state. The voltage dependence curves of the differential conductivity scaled by the mesa perimeter collapse onto a single curve at lower voltages, while those scaled by mesa area are on a single curve at higher voltages. This shows that the current flows through the surface of the sample at low-voltage region and through the bulk at high-voltage region. A crossover from the surface transport to the bulk transport occurs in a fairly narrow range of the bias voltage.

A rare, compound adrenal tumor consisting of ganglioneuroblastoma and pheochromocytoma was completely resected in an adult woman. Most of the tumor was occupied by the ganglioneuroblastoma component. This ganglioneuroblastoma was an intermixed tumor, which is known to have a favorable prognosis in children. Based on the lack of spread, the resectability of the tumor, and the histology of the ganglioneuroblastoma, no adjuvant therapy was employed. There was no evidence of recurrence at the 5-year follow-up. This suggests that adjuvant therapy may not be necessary in these compound tumors.