Search

We converted Gaussian-distributed voltage noise applied to an electron reservoir into the non-equilibrium free energy of a nanometer-scale dot connected to the reservoir via an energy barrier. Counting statistics of single-electron motion into and out of the dot through the energy barrier allows us to quantitatively analyze the energy transported into the dot as well as changes in the internal energy and effective temperature of the dot in this noise-induced non-equilibrium steady state (NESS). By analyzing the transition rates of electrons moving into and out of the dot, we confirmed that the rectification effect caused by the asymmetry with respect to the direction of electron motion is the origin of the increase in the internal energy of the dot. The information on energy transport in a nanometer-scale dot in the noise-induced NESS obtained in this study with electron counting statistics clarifies the relationship between the non-equilibrium dynamics of a nanodevice and noise applied to it. This study provides us with the means to evaluate device operation using noise as a resource.

Theoretical treatments of polymer dynamics in liquid generally start with the basic assumption that motion at the smallest scale is heavily overdamped; therefore, inertia can be neglected. We report on the Brownian motion of tethered DNA under nanoconfinement, which was analyzed by molecular dynamics simulation and nanoelectrochemistry-based single-electron shuttle experiments. Our results show a transition into the ballistic Brownian motion regime for short DNA in sub-5-nm gaps, with quality coefficients as high as 2 for dsDNA, an effect mainly attributed to a drastic increase in stiffness. The possibility for DNA to enter the underdamped regime could have profound implications on our understanding of the energetics of biomolecular engines such as the replication machinery, which operates in nanocavities of a few nanometers wide.

Despite several demonstrations of electrochemical devices with limits of detection (LOD) of 1 cell/mL, the implementation of single-cell bioelectrochemical sensor arrays has remained elusive due to their challenging implementation at large scale. Here, we show that the recently introduced nanopillar array technology combined with redox-labelled aptamers targeting epithelial cell adhesion molecule (EpCAM) is perfectly suited for such implementation. Combining nanopillar arrays with microwells determined for single cell trapping directly on the sensor surface, single target cells are successfully detected and analyzed. This first implementation of a single-cell electrochemical aptasensor array based on Brownian-fluctuating redox species opens new opportunities for large-scale implementation and statistical analysis of early cancer diagnosis and cancer therapy in clinical settings.

Background Chronic kidney disease–mineral and bone disorder (CKD–MBD), nutritional status, and uremia management have been emphasized for bone management in hemodialysis patients. Nevertheless, valuable data on the importance of muscle mass in bone management are limited, including whether conventional management alone can prevent osteoporosis. Thus, the importance of muscle mass and strength, independent of the conventional management in osteoporosis prevention among hemodialysis patients, was evaluated. Methods Patients with a history of hemodialysis 6 months or longer were selected. We assessed the risk for osteoporosis associated with calf circumference or grip strength using multivariable adjustment for indices of CKD–MBD, nutrition, and dialysis adequacy. Moreover, the associations between bone mineral density (BMD), calf circumference, grip strength, and bone metabolic markers were also evaluated. Results A total of 136 patients were included. The odds ratios (95% confidence interval) for osteoporosis at the femoral neck were 1.25 (1.04–1.54, P P P P Conclusion Shorter calf circumference or weaker grip strength was associated with osteoporosis risk and lower BMD among hemodialysis patients, independent of the conventional therapies.

Patients with primary aldosteronism have a higher risk of chronic kidney disease. Visceral fat tissue is hypothesized to stimulate the adrenal glands to overproduce aldosterone, and aldosterone promotes visceral fat tissue to produce inflammatory cytokines. However, it is unclear whether the volume of accumulated visceral fat tissue is associated with renal impairment among patients with hyperaldosteronism. We conducted a single-center cross-sectional study to assess the association between the estimated glomerular filtration rate and the ratio of the visceral-to-subcutaneous fat volume calculated by computed tomography. One hundred eighty patients with primary aldosteronism were enrolled. The mean ± SD age was 52.7 ± 11.0 years, and 60.0% were women. The ratio of visceral-to-subcutaneous fat volume was highly correlated with the estimated glomerular filtration rate (r = 0.49, p, The ratio of visceral-to-subcutaneous fat tissue volume was significantly associated with eGFR among 180 primary aldosteronism patients, showing an interaction between the ratio and plasma aldosterone concentration.

A woman in her thirties developed complex regional pain syndrome in her left shoulder due to a traffic accident. She demonstrated autonomic nervous symptoms (swelling, sweating, and skin color asymmetry) in her left hand, severe allodynia, neglect-like symptoms (NLS), impaired body image associated with impaired body awareness, and functional impairment of the left shoulder and elbow. She also reported physical self-disgust toward her affected limb, describing it as “reptilian,” as well as aversion to touching others; this body awareness exacerbated her pain and NLS. We therefore conducted stepwise interventions using body shadows. The intervention did not trigger physical self-disgust, enabling formation of body ownership and a body image unaccompanied by pain. Consequently, the patient showed improvements in pain, NLS, and autonomic nervous symptoms.

Background Tolvaptan (TLV) is reported to improve diuretic effects in patients with chronic kidney disease (CKD) when furosemide (FUR) is not sufficiently effective. However, it is not clear whether TLV addition is effective for advanced CKD patients with heart failure. Methods An open-label, parallel-group randomized trial was performed. The subjects were 33 patients with CKD stage G3–G5 who had fluid overload despite taking 20–100 mg/day FUR. They were divided into two groups: a group administered 15 mg/day TLV plus their original FUR dose for 7 days (TLV group), and a group administered 120–200 mg/day FUR (i.e., 100 mg/day over their previous dose) for 7 days (FUR group). Results The mean change in urine volume was significantly higher in the TLV group compared to the FUR group (637 ml vs 119 ml; p p Conclusions In patients with advanced CKD with fluid overload, the addition of TLV achieved a significantly higher urine volume with less adverse effects on renal function compared with increasing the dose of FUR. The efficacy and safety of TLV were higher in patients who had higher urine osmolality and lower serum sodium before treatment. Clinical trial registration UMIN000014763.

We demonstrate charge detection with single-electron resolution at high readout frequency using a silicon field-effect transistor (FET) integrated with double resonant circuits. A FET, whose channel of 10-nm width enables a single electron to be detected at room temperature, is connected to resonant circuits composed of coupled inductors and capacitors, and these double resonant circuits provide two resonance frequencies. When the FET is driven by a carrier signal at the lower resonance frequency, a small signal applied to the FET's gate modulates the resonance condition, resulting in a reflected signal appearing near the higher resonance frequency. Such operation utilizing the double resonant circuits enables charge detection with a single-electron resolution of 3 × 10−3 e/Hz0.5 and a readout frequency of 200 MHz at room temperature. In addition, a variable capacitor used in the double resonant circuits allows charge-sensing characteristics to be controlled in situ.

Background We previously showed Lipin1 (LPIN1) to be a candidate gene for essential hypertension by genome-wide association studies. LPIN1 encodes the Lipin 1 protein, which contributes to the maintenance of lipid metabolism and glucose homeostasis. However, little is known about the association between LPIN1 and blood pressure (BP). Methods We evaluated the BP of LPIN1-deficient [fatty liver dystrophy (fld)] mice and explored related mechanisms. Results Fld mice have very low expression of LPIN1 and exhibit fatty liver, hypertriglyceridemia, insulin resistance and peripheral neuropathy. Fld mice had significantly elevated SBP and heart rate (HR) throughout the day as measured by a radiotelemetric method. Diurnal variation of SBP and HR was also absent in fld mice. Furthermore, urinary excretion of adrenaline and noradrenaline by fld mice was significantly higher compared with that of control mice. The BP response of fld mice to clonidine (a centrally acting α2-adrenergic receptor agonist) was greater than that of control mice. However, levels of Angiotensinogen and Renin 1 mRNA and urinary nitric oxide excretion were comparable between the two groups. The decrease in SBP at 8 weeks after fat grafting surgery was significantly greater in the transplant group compared with the sham operated group. Conclusion The elevated BP in fld mice may result from activation of the sympathetic nervous system through decreased levels of adipose cytokines. These results indicate that LPIN1 plays a crucial role in blood pressure regulation and that LPIN1 is a new target gene for essential hypertension.

We performed electron counting statistics to measure the thermoelectric effect in a nanometer-scale silicon dot. To separate the 100-nm-long dot from a silicon nanowire, we used an electrostatically created 30-nm-long energy barrier. By measuring current through a nearby sensor, we observed the random motion of single electrons between the dot and silicon nanowire. The statistics of single-electron motion provides us with information on temperature and voltage at the dot. Under the detailed balance assumption, we determined the temperature difference and the Seebeck voltage between the dot and silicon nanowire. The validity of our analysis was confirmed by observing the energy-barrier height dependence of the Seebeck coefficient. Furthermore, by counting the electrons leaving the dot, a minute output power on the order of sub-zeptowatt from the dot to the silicon nanowire was estimated.

The Hokkaido Eastern Iburi Earthquake (M = 6.7) occurred on Sep. 6, 2018 in the southern part of Central Hokkaido, Japan. Since Paleogene, this region has experienced the dextral oblique transpression between the Eurasia and North American (Okhotsk) Plates and the subsequent collision between the Northeast Japan Arc and the Kuril Arc due to the oblique subduction of the Pacific Plate. This earthquake occurred beneath the foreland fold-and-thrust belt of the Hidaka Collision zone developed by the collision process, and is characterized by its deep focal depth (~ 37 km) and complicated rupture process. The reanalyses of controlled source seismic data collected in the 1998–2000 Hokkaido Transect Project revealed the detailed structure beneath the fold-and-thrust belt, and its relationship with the aftershock activity of this earthquake. Our reflection processing using the CRS/MDRS stacking method imaged for the first time the lower crust and uppermost mantle structures of the Northeast Japan Arc underthrust beneath a thick (~ 5–10 km) sedimentary package of the fold-and-thrust belt. Based on the analysis of the refraction/wide-angle reflection data, the total thickness of this Northeast Japan Arc crust is only 16–22 km. The Moho is at depths of 26–28 km in the source region of the Hokkaido Eastern Iburi Earthquake. Our hypocenter determination using a 3D structure model shows that most of the aftershocks are distributed in a depth range of 7–45 km with steep geometry facing to the east. The seismic activity is quite low within the thick sediments of the fold–thrust belt, from which we find no indication on the relationship of this event with the shallow (

Photo-excited carriers in Si quantum islands and their surrounded area exhibit interesting features due to electron-hole generation. We show Si single- hole transistor (SHT) characteristics in a Si single-electron transistor (SET) comprising n-type source and drain electrodes under illumination. Holes excited in the Si are expected to flow through the SET island by applying negative gate voltages. Interesting phenomenon is the co-existence of electrons and holes around the island. In a SET, when holes generated by photo-excitation are trapped in the one side (either top or bottom side) of the SET island under the vertical electric field, the SET characteristics are changed depending on the number of trapped holes because effective total number of electrons can be negative. Here, we show the characteristics of photo-excited SETs without strong vertical electric fields.

The target of diastolic blood pressure (DBP) remains controversial in patients with coronary artery disease (CAD). We systematically searched PubMed/Medline and the Cochrane Central database for randomized controlled trials (RCTs) assessing the efficacy and safety of reducing DBP in CAD patients from January 1965 to July 2017. Seven placebo-controlled RCTs enrolling 34,814 CAD patients who achieved DBP

Understanding nonequilibrium electron dynamics in a tunable-barrier dynamic quantum dot is vital to achieve high-accuracy single-electron pumping, which has applications to metrological standards and quantum information devices. However, the dynamic mechanism determining the pumping process has not been fully understood. In this paper, we study and clarify the physical mechanisms of single-electron pumping by analyzing and calculating master equations with a realistic model in detail. Our focus is mainly on the regime which lies at the crossover between the two extreme physical models of single-electron pumping. The mechanism crossover strongly depends on a capacitive coupling between a gate for tuning the barrier and the quantum dot. We find that there is an optimal value of the coupling with the best pumping accuracy and the mechanism crossover depends on gate voltage in some range of the coupling values. Our results offer a guideline for evaluation of pumping characteristics and for optimization of the device structure, which is an important step toward understanding high-speed nonequilibrium electron dynamics and realizing reproducible high-accuracy single-electron pumps.

The JAXA/Hayabusa mission was the first asteroid sample return in the world. The target asteroid was (25,143) Itokawa, a small (500 m of size) S-type near-Earth asteroid. Hayabusa, which was launched in May 2003, arrived at Itokawa in September 2005, offering the first opportunity to see a very tiny asteroid in detail. To our surprise, the asteroid surface did not show clear craters, but was covered by a lot of boulders. Hayabusa observed Itokawa by its four scientific instruments and tried to collect surface materials by touchdown twice. However, the touchdown operations were not executed as planned and Hayabusa had serious problems after the second touchdown. Nevertheless, Hayabusa successfully brought thousands of small grains from Itokawa back to the Earth in June 2010. We studied Itokawa in detail by both remote sensing data and returned samples, and we revealed a lot of new information to study its origin and evolution.

We compare an electron pump and an ultrastable low-noise current amplifier (ULCA) as reference current sources for calibrating a high-gain current preamplifier at pA-level currents. Using the electron pump on a quantized current plateau, the current noise is dominated by the device under test, whereas using the ULCA, the larger ULCA noise is the biggest contribution. In a 20-second measurement at a nominal current of 3.2 pA, the preamplifier gain is resolved with a relative type A uncertainty of $5\times 10^{-5}$ using the pump, and $2\times 10^{-4}$ using the ULCA.

We have directly compared the current from two dissimilar quantized charge pumps each pumping one electron per cycle at 825 MHz. The currents are equal to within roughly 1 part in 106, although a long time constant of unknown origin prevents stronger conclusions to be drawn from the data. This is the first report of a direct universality test of electron pumps.

Current enhancement without increasing the input power is a critical issue to be pursued for electronic circuits. However, drivability of metal-oxide-semiconductor (MOS) transistors is limited by the source-injection current, and electrons that have passed through the source unavoidably waste their momentum to the phonon bath. Here, we propose the Si electron-aspirator, a nanometer-scaled MOS device with a T-shaped branch, to go beyond this limit. The device utilizes the hydrodynamic nature of electrons due to the electron–electron scattering, by which the injected hot electrons transfer their momentum to cold electrons before they relax with the phonon bath. This momentum transfer induces an electron flow from the grounded side terminal without additional power sources. The operation is demonstrated by observing the output-current enhancement by a factor of about 3 at 8 K, which reveals that the electron–electron scattering can govern the electron transport in nanometer-scaled MOS devices, and increase their effective drivability., Power dissipation is usually unavoidable in transistor channels due to the inelastic scattering of electrons. Here, Firdaus et al. propose a nanoscaled silicon electron-aspirator to remove this constraint, which shows enhanced current output by 3 times at 8 K without additional power supply.

We have numerically calculated transport characteristics on a Miller-Abraham network in a non-linear regime by solving the Kirchhoff's current law at each site. Assuming the Mott model, we obtained the relation between current density and electric field, J ∝ exp ( γ E ) , which has often been observed in low-mobility materials and whose mechanism has been a source of controversy for over half a century. Our numerical calculation makes it possible to analyze the energy configuration of relevant hopping sites and visualize percolation networks. Following the percolation theory proposed by Shklovskii [Shklovskii, Sov. Phys. Semicond. 10, 855 (1976)], we show that the main mechanism of the field dependence is the replacement of dominating resistances accompanied by the geometrical evolution of the percolation networks. Our calculation is so general that it can be applied to hopping transport in a variety of systems.

The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments.This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension.Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = -0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022).Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.