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Spin-orbit coupling (SOC) is pivotal for various fundamental spin-dependent phenomena in solids and their technological applications. In semiconductors, these phenomena have been so far studied in relatively weak electron-electron interaction regimes, where the single electron picture holds. However, SOC can profoundly compete against Coulomb interaction, which could lead to the emergence of unconventional electronic phases. Since SOC depends on the electric field in the crystal including contributions of itinerant electrons, electron-electron interactions can modify this coupling. Here we demonstrate the emergence of SOC effect in a high-mobility two-dimensional electron system in a simple band structure MgZnO/ZnO semiconductor. This electron system features also strong electron-electron interaction effects. By changing the carrier density with Mg-content, we tune the SOC strength and achieve its interplay with electron-electron interaction. These systems pave a way to emergent spintronic phenomena in strong electron correlation regime and to the formation of novel quasiparticles with the electron spin strongly coupled to the density., Main Text (4 Figures), Supplementary notes (4 Figures)

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.

Electrons in conventional metals become less mobile under the influence of electron correlation. Contrary to this empirical knowledge, we report here that electrons with the highest mobility ever found in known bulk oxide semiconductors emerge in the strong-correlation regime of the Dirac semimetal of perovskite CaIrO3. The transport measurements reveal that the high mobility exceeding 60,000 cm2V−1s−1 originates from the proximity of the Fermi energy to the Dirac node (ΔE, Electron correlation normally makes electrons less mobile, but it is still not clear when correlation becomes very strong in Dirac semimetals. Here, Fujioka et al. report a very high electron mobility exceeding 60,000 cm2V−1s−1 in correlated Dirac semimetal of perovskite CaIrO3, due to the enhanced electron correlation nearby the Mott transition.

Epitaxial thin films of ${({\mathrm{Sn}}_{x}{\mathrm{Pb}}_{1\ensuremath{-}x})}_{1\ensuremath{-}y}{\mathrm{In}}_{y}\mathrm{Te}$ were successfully grown by molecular-beam epitaxy in a broad range of compositions ($0\ensuremath{\le}x\ensuremath{\le}1$, $0\ensuremath{\le}y\ensuremath{\le}0.23$). We investigated electronic phases of the films by the measurements of electrical transport and optical second-harmonic generation. In this system, one can control the inversion of the band gap, the electric polarization that breaks the inversion symmetry, and the Fermi-level position by tuning the Pb/Sn ratio and In composition. A plethora of topological electronic phases is expected to emerge, such as the topological crystalline insulator, the topological semimetal, and superconductivity. For the samples with large Sn compositions $(xg0.5)$, hole density increases with In composition $(y)$, which results in the appearance of superconductivity. On the other hand, for those with small Sn compositions $(xl0.5)$, an increase in In composition reduces the hole density and changes the carrier type from $p$ type to $n$ type. In a narrow region centered at $(x,y)=(0.16,0.07)$ where the $n$-type carriers are slightly doped, charge transport with high mobility exceeding $5000\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{2}\phantom{\rule{0.16em}{0ex}}{\mathrm{V}}^{\text{--}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\text{--}1}$ shows up, representing the possible semimetal states. In those samples, the optical second-harmonic generation measurement showing the breaking of inversion symmetry along the out-of-plane [111] direction, which is a necessary condition for the emergence of the polar semimetal state. The thin films of ${({\mathrm{Sn}}_{x}{\mathrm{Pb}}_{1\ensuremath{-}x})}_{1\ensuremath{-}y}{\mathrm{In}}_{y}\mathrm{Te}$ material systems with a variety of electronic states would become a promising materials platform for the exploration of novel quantum phenomena.

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.

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

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 a proximity-driven large anomalous Hall effect in all-telluride heterostructures consisting of ferromagnetic insulator Cr2Ge2Te6 and topological insulator (Bi,Sb)2Te3. Despite small magnetization in the (Bi,Sb)2Te3 layer, the anomalous Hall conductivity reaches a large value of 0.2e2/h in accord with a ferromagnetic response of the Cr2Ge2Te6. The results show that the exchange coupling between the surface state of the topological insulator and the proximitized Cr2Ge2Te6 layer is effective and strong enough to open the sizable exchange gap in the surface state., 33 pages, 12 figures including supplemental material, accepted by PRL

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.

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.

Instability of quantum anomalous Hall (QAH) effect has been studied as function of electric current and temperature in ferromagnetic topological insulator thin films. We find that a characteristic current for the breakdown of the QAH effect is roughly proportional to the Hall-bar width, indicating that Hall electric field is relevant to the breakdown. We also find that electron transport is dominated by variable range hopping (VRH) at low temperatures. Combining the current and temperature dependences of the conductivity in the VRH regime, the localization length of the QAH state is evaluated to be about 5 $\mu$m. The long localization length suggests a marginally insulating nature of the QAH state due to a large number of in-gap states., Comment: 5 pages, 4 figures, accepted for publication in PRL

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.

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 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 report an electronic magnetization measurement of a quantum point contact (QPC) based on nuclear magnetic resonance (NMR) spectroscopy. We find that NMR signals can be detected by measuring the QPC conductance under in-plane magnetic fields. This makes it possible to measure, from Knight shifts of the NMR spectra, the electronic magnetization of a QPC containing only a few electron spins. The magnetization changes smoothly with the QPC potential barrier height and peaks at the conductance plateau of 0.5 $\times$ $2e^2/h$. The observed features are well captured by a model calculation assuming a smooth potential barrier, supporting a no bound state origin of the 0.7 structure., 5 pages main text + 6 pages supplementary material. Accepted for publication in Phys. Rev. Lett

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.

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

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.

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.

To determine the factors that affect seasonal variation in blood pressure (BP) in a fairly large number of patients with essential hypertension who stayed almost entirely indoors in a stable environmental temperature and who took a calcium channel blocker during the study. This prospective study of hypertensive patients was conducted during the summer and winter. BP was measured by ambulatory blood pressure monitoring; the indoor temperature was measured at the time of the BP measurement using an electrothermometer with the subject awake and indoors. Subjects comprised 38 men and 57 women. The subjects spent virtually the entire day indoors during both the summer (men, 22.1±1.6h; women, 23.0±0.9h) and winter (men, 23.0±0.9h; women, 22.9±0.9h). During the waking hours, the systolic/diastolic BPs were significantly higher during the winter than the summer. The differences were 8±9/4±5mmHg in men and 5±11/2±6mmHg in women; these values were not significantly different between men and women. No significant seasonal differences in BP during the sleeping hours were noted. There was a significant difference of approximately 6°C in the environmental temperature during waking hours, but there was no significant difference in urinary excretion of sodium or in exercise activity between the seasons. Only body height was significantly correlated with the winter increase in waking BP in both men and women, even after adjustment for potential confounding variables. Body height was a determinant of the increase in waking BP during the winter in hypertensive patients who lived almost entirely indoors. (Hypertens Res 2000; 23: 587-592)

A 42-year-old man had biochemical and somatic abnormalities compatible with pseudohypoparathyroidism type I (PsHP) and also had high plasma renin activity (PRA). After 1, 25-dihydroxyvitamin D (calcitriol) supplementation the systolic/diastolic blood pressure, assessed by 24-hour non-invasive ambulatory blood pressure monitoring, was reduced from 145/96 mmHg to 128/85 mmHg with normalization of the serum calcium level and its related hormones, as well as decreased PRA. Calcitriol supplementation successfully reduced the blood pressure in this patient with PsHP and a high PRA, suggesting that calcium-related hormones and/or the renin-angiotensin system were involved in lowering the blood pressure.(Internal Medicine 38: 31-35, 1999)

To evaluate the effects of prolonged intake of a high-sodium diet on glucose and lipid metabolism, we examined the relation of daily urinary sodium excretion to blood pressure, glucose metabolism, and lipid metabolism in 140 Japanese adults who lived in a region where the average daily consumption of sodium was high and stable during the past 15 yr; no subject had received any treatment for hypertension or metabolic disorders. Each subject was admitted to our health examination center for 2 d for measurement of blood pressure, sampling of blood, and glucose tolerance testing. A 24-h urine specimen was collected by each subject after discharge. Multiple regression analysis revealed that urinary sodium excretion was significantly independent of the mean blood pressure and was unrelated to the area under the serum glucose curve after glucose administration. The urinary sodium level was also unrelated to low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol. The prevalence of hypertension in the group with a daily sodium excretion below 140 mEq (low sodium group) was 0%, while that in the group with a daily sodium excretion above 280 mEq (high sodium group) was 44%; this difference was significant (p < 0.01). No significant difference was observed in the prevalence of metabolic disorders between the two groups. Our results suggest that sodium intake has little influence on glucose and lipid metabolism but has a significant influence on blood pressure in normotensive and untreated hypertensive subjects who reside in an area with a relatively high sodium intake.

We study dynamic polarization and resistive detection of nuclear spins in a semiconductor quantum dot (QD) under the Kondo effect regime. We find that the differential conductance spectra of the QD exhibit hysteresis under the Kondo effect regime in magnetic fields. Relevance of nuclear spins to the hysteresis is confirmed by the detection of nuclear magnetic resonance signals by monitoring the differential conductance. We attribute the origin of the hysteresis to the dynamic nuclear spin polarization (DNP) induced in the QD. Using the DNP, we demonstrate nuclear spin relaxation rate measurements in the QD under the Kondo effect regime., Comment: 5 pages, 6 figures, accepted for publication in Phys. Rev. B

We investigated the correlations between the reduction in body weight (BW) induced by calorie restriction and reductions in blood pressure (BP) and improvement in metabolic disorders in overweight women with essential hypertension. After eating a standard diet (diet-I) for 2 weeks, women in the calorie-restricted group (n=25) received a low calorie diet for 2 weeks, and then standard diet-II for 1 week. Women in the calorie-nonrestricted group (n=13) ate standard diet-I for 5 weeks. The calorie-restricted group exhibited a significant reduction in BP in association with loss of BW; their levels of low-density lipoprotein cholesterol, and triglycerides levels, and their fasting levels of glucose and insulin were also reduced compared with the calorie-nonrestricted group. However, there were no significant differences in the level of high-density lipoprotein cholesterol, the areas under the 2-h glucose and insulin curves (AUCglu and AUCins), or the ratio of AUCglu to AUCins between groups. The change in BW was significantly correlated with a reduction in BP (r=0.62, p

The accuracy of the casual urine (CU) method for estimating daily salt intake was compared with the second morning urine (SMU) method and with 24-h urine collection (24 UC) method as the gold standard. Data were obtained from three previously reported studies, in which we evaluated the daily salt intake by the SMU method. Using SMU samples from 1315 outpatients, the estimated salt intake was lower with the CU method than the SMU method. In inpatients with a daily salt intake of 7, 8 or 18 g, the CU method was applied to SMU specimens. It underestimated salt intake compared with the 24-h collection method whereas the SMU method and 24 UC method gave similar results. In the present study, 24 UC was done and then urine was collected at 0800, 1100, 1400, 1700 and 1900 hours, with a daily salt intake of 6 g in 8 inpatients, 10 g in 11 inpatients or 15 g in 5 inpatients. In comparison with the 24 UC method, the CU method underestimated a high salt intake (15 g) when morning specimens were used and overestimated a low salt intake (6 g) when afternoon specimens were used. The correlation between the CU method and 24 UC method was weaker (R = 0.57) than that between the SMU method and 24 UC method (R = 0.85). In conclusion, the CU method is heavily influenced by the timing of urine collection and by the actual daily salt intake, so the SMU method provides a better estimate of individual salt intake.

We investigate Dirac fermions on the surface of the topological insulator ${\text{Bi}}_{2}{\text{Se}}_{3}$ using scanning tunneling spectroscopy. Landau levels (LLs) are observed in the tunneling spectra in a magnetic field. In contrast to LLs of conventional electrons, a field-independent LL appears at the Dirac point, which is a hallmark of Dirac fermions. A scaling analysis of LLs based on the Bohr-Sommerfeld quantization condition allowed us to determine the dispersion of the surface band. Near the Fermi energy, fine peaks mixed with LLs appear in the spectra, which may be responsible for the anomalous magnetofingerprint effect [J. G. Checkelsky et al., Phys. Rev. Lett. 103, 246601 (2009)].

We studied spatial distribution of dynamic nuclear polarization (DNP) in a Hall-bar device in a breakdown regime of the quantum Hall effect (QHE). We detected nuclear magnetic resonance (NMR) signals from the polarized nuclear spins by measuring the Hall voltage $V_{xy}$ using three pairs of voltage probes attached to the conducting channel of the Hall bar. We find that the amplitude of the NMR signal depends on the position of the Hall voltage probes and that the largest NMR signal is obtained from the pair of probes farthest from the electron-injecting electrode. Combined with results on pump-and-probe measurements, we conclude that the DNP induced by QHE breakdown develops along the electron-drift direction., Comment: 4 pages, 4 figures, accepted for publication in PRB

Angiotensin II does not increase renal prostaglandin E2 in response to pressure reduction. Whether angiotensin II (Ang II) stimulates renal secretion of prostaglandin E2 (PGE2) synthesized in response to pressure reduction was examined. PGE2 and Ang II in aortic and renal venous plasma were measured before and during renal arterial constriction in anesthetized dogs, with or without an intrarenal arterial infusion of an Ang II antagonist, losartan potassium (1 mg/min), or saralasin (3 µg/min). In other anesthetized dogs, two doses of Ang II (30 and then 300 ng/min) were infused into the renal artery, and plasma Ang II levels and renal PGE2 secretion were measured. When renal perfusion pressure was reduced to 75 and 45mm Hg by constriction, the renal secretion of PGE2 increased seven- and fourfold, respectively. Ang II levels in the renal venous plasma increased from 6.6 ± 1.8 to 21.7 ± 7.4 and then 48.1 ± 15.3 pg/ml (both P < 0.05) as the pressure decreased. Neither losartan nor saralasin suppressed the response of renal PGE2 secretion to the pressure reduction. The intrarenal infusion of Ang II (30 ng/min) elevated the Ang II level in the renal venous plasma from 9.8 ± 4.6 to 33.7 ± 4.2 pg/ml (P < 0.01), but did not increase PGE2 secretion. The higher dose (300 ng/min) of Ang II increased it, but the Ang II level in the renal venous plasma was 166 ± 63 pg/ml. These results suggest that the greater part of the increased renal synthesis of PGE2 in response to pressure reduction is not mediated by Ang II.

This study was performed to elucidate the effect of a hypocaloric diet on blood pressure and sodium balance in overweight women with essential hypertension. Hospitalized patients were fed a hypocaloric diet (900 kcal/day) for 3 weeks after being fed a standard diet (SD) for more than 2 weeks. During the study, the sodium and potassium intake was kept constant as was the level of exercise activity. After the mean arterial pressure (MAP) and body weight had stabilized during the last week on the SD, caloric restriction significantly reduced the body weight by 1.5kg in the first week and by 0.8-0.9 kg in subsequent weeks, and reduced the MAP by 5mmHg and by 1-3mmHg, respectively. Although caloric restriction reduced the excretion of urinary norepinephrine and C-peptide, and elevated the serum levels of ketone bodies that would induce natriuresis, the urinary sodium excretion remained unchanged, indicating that sodium balance was unchanged even by caloric restriction. These results suggest that caloric restriction lowers the blood pressure in a short time with no significant change in sodium balance. (Hypertens Res 1992; 15: 137-142)

INAGAMI, T., MIZUNO, K., KAWAMURA, M., OKAMURA, T., CLEMENS, D.L. and HIGASHIMORI, K. Localization of Components of the Renin-Angiotensin System within the Kidney and Sustained Release of Angiotensins from Isolated and Perfused Kidney. Tohoku J. Exp. Med., 1992, 166 (1), 17-26-We found colocalization of renin, angiotensin (Ang) I and Ang II in juxtaglomerular (JG) cells of the kidney. Coexistence of Ang II in renin granules was demonstrated by electron microscopic immunogold labeling of these components. Coexistence of both Ang I and Ang II in the high density renin storage granules were also demonstrated by gradient centrifugation of renal homogenate. These findings supported the synthesis of Ang I and Ang II in juxtaglomerular cells. Isolated and cultured JG cells showed the synthesis of Ang I, Ang II and renin. Ang I and Ang II were secreted from isolated and perfused rat kidneys at steady rates over 2hr. Their secretion rates were proportional to that of renin. The rate of Ang II secretion from the kidney was higher than that from the vascular bed. Ang II was also found in renal lymph. These findings indicate that a large amount of Ang II is generated in JG cells by the intracellular action of renin and may play a significant role in the regulation of renal function.