Electric field induced effects in Y3N@[C80]6- anionic solid

By measuring the i−vi−v characteristics of Y3N@[C80]6− anionic solid at various temperatures and electric field strengths, four conducting phases with i∝vi∝v , i∝v2i∝v2 with low resistance, i∝v4i∝v4 and i∝v2i∝v2 with high resistance were observed. First, at temperatures below 100 K and field strengths below 30 Vcm−1Vcm−1 , the current passing through the sample was a linear function of the d.c. bias voltage due to free moving charges. Second, at the same field strengths, the trapped carrier was thermally activated with activation energies of 13.6 meV for temperature range of 100−250100−250 K and 88.7 meV for 250−450250−450 K. In this conducting phase, the carrier transport was governed by space charge limited conduction mechanism. Third, when the electric field increased from 30 to 120 Vcm−1Vcm−1 , the ii became a quartic function of the vv because the carrier mobility is a quadratic function of the field strength. A conducting phase with high resistance was observed at temperatures below 100 K. The trapped carrier was thermally activated with activation energies of 146.5 meV for temperature range of 100−250100−250  K and 288.5 meV for 250−450250−450  K. Finally, in the electric field strengths of 120−2000120−2000 Vcm−1Vcm−1 , a high resistance phase appeared in the anionic solid at temperatures below 100 K. The current was a quadratic function of the d.c. bias voltage, and the carrier mobility was independent of the field strength

Evaluation of Cardiovascular Stress Reaction Using HPCD Method on a Beat-by-beat Basis

In order to establish a bionic model/system in cardiovascular fields, comprehension of hemodynamics is important. In this study, a novel beat-by-beat hemodynamic system evaluation method named “beat-by-beat HPCD method” is proposed and evaluated.　Gregg’s theoretically driven model of hemodynamics which was called “HPCD method” is improved by using non-invasive and beat-by-beat cardiovascular measurement of mean blood pressure and cardiac output. Continuous beat-by-beat measurements of MBP and CO were done on three healthy male subjects during three hours. In the measurement, a five minutes cold pressor test was executed in each subject and also each subject did exercise using a bicycle ergometer in five minutes and walked during 15 minutes. Measured beat-by-beat MBP and CO can derive beat-by-beat HP (hemodynamic profile) and CO (compensation deficit). Then, beat-by-beat changes clearly observed from plots on HP axis and CD axis plane. More vascular response can be observed on cold pressor and more myocardial response can be observed on ergometer exercise. During walking period, the response is intermediate between cold pressor and ergometer exercise. Finally, the proposed method can be considered as applicable to evaluate cardiovascular bionic system especially on evaluation of a person being subjected to stress. Keywords: hemodynamics; stress; cardiovascular system; hemodynamic profile and compensation deficit mode

Mechanisms involved in extraterritorial facial pain following cervical spinal nerve injury in rats

<p>Abstract</p> <p>Background</p> <p>The aim of this study is to clarify the neural mechanisms underlying orofacial pain abnormalities after cervical spinal nerve injury. Nocifensive behavior, phosphorylated extracellular signal-regulated kinase (pERK) expression and astroglial cell activation in the trigeminal spinal subnucleus caudalis (Vc) and upper cervical spinal dorsal horn (C1-C2) neurons were analyzed in rats with upper cervical spinal nerve transection (CNX).</p> <p>Results</p> <p>The head withdrawal threshold to mechanical stimulation of the lateral facial skin and head withdrawal latency to heating of the lateral facial skin were significantly lower and shorter respectively in CNX rats compared to Sham rats. These nocifensive effects were apparent within 1 day after CNX and lasted for more than 21 days. The numbers of pERK-like immunoreactive (LI) cells in superficial laminae of Vc and C1-C2 were significantly larger in CNX rats compared to Sham rats following noxious and non-noxious mechanical or thermal stimulation of the lateral facial skin at day 7 after CNX. Two peaks of pERK-LI cells were observed in Vc and C1-C2 following mechanical and heat stimulation of the lateral face. The number of pERK-LI cells in C1-C2 was intensity-dependent and increased when the mechanical and heat stimulations of the face were increased. The decrements of head withdrawal latency to heat and head withdrawal threshold to mechanical stimulation were reversed during intrathecal (i.t.) administration of MAPK/ERK kinase 1/2 inhibitor PD98059. The area of activated astroglial cells was significantly higher in CNX rats (at day 7 after CNX). The heat and mechanical nocifensive behaviors were significantly depressed and the number of pERK-LI cells in Vc and C1-C2 following noxious and non-noxious mechanical stimulation of the face was also significantly decreased following i.t. administration of the astroglial inhibitor fluoroacetate.</p> <p>Conclusions</p> <p>The present findings have demonstrated that mechanical allodynia and thermal hyperalgesia occur in the lateral facial skin after CNX and also suggest that ERK phosphorylation of Vc and C1-C2 neurons and astroglial cell activation are involved in orofacial extraterritorial pain following cervical nerve injury.</p

Fish bone migration after pancreaticoduodenectomy: Incidence and treatment options

Objective: Migration of a fish bone to the bile duct or pancreatic duct is a possible complication after pancreaticoduodenectomy (PD). The aim of this study was to clarify the incidence and indications for intervention in such cases. Methods: We reviewed the cases with fish bone migration after PD detected on computed tomography (CT) scan between October 2000 and October 2020 were reviewed and the incidence of fish bone migration, presence of symptoms and signs, therapeutic modalities and patient outcomes were analyzed. Results: Among the 1475 PD procedures performed at our institution during the study period, 14 cases of fish bone migration were noted on CT, the incidence of which was 0.95% (14/1475). The time duration from surgery to the detection of fish bone ranged from 88 to 5902 days (median 917 d). Ten patients remained asymptomatic without therapeutic intervention for up to 2919 days (median 509 d). Four patients were treated by endoscopy, either at the patient's request (n = 1) or because of their symptoms (n = 3), and removal was successful in three cases but failed in one case in which the fish bone migrated to the right intrahepatic bile duct. No surgical treatment was required in any case. Conclusions: The incidence of fish bone migration on CT after PD was about 1%. Some cases resolved spontaneously, and most of the asymptomatic cases required no intervention. For symptomatic cases, endoscopic treatment should be considered first. It is important to confirm the location of the fish bone by CT and determine whether it can be removed.journal articl

Evaluation of a newly designed endoscope for observing inner wall of large arteries for the use of endovascular intervention

A prototype endoscope for observing inner wall of large arteries was specially designed and evaluated through in vitro and in vivo tests. The purpose of this endoscope is to visualize the inner wall of large arteries, e.g., an aorta, without blocking off the blood stream aiming for the use of an assistive technique for endovascular interventions such as stent-graft placement for aortic aneurysm. The technique newly introduced for this purpose was the use of intermittent high-pressure saline jet synchronized to heart beat (diastolic phase). In the previous studies using commercially available bronchoscopes, we confirmed the validity of the system utilizing this technique [1, 2]. Based on these findings, in this study, we have specially designed a new endoscope with two channels, one for saline discharge and the other for forceps, and evaluated its performance through in vitro and in vivo tests. From the results of in vitro tests using a mock circulation system, it was confirmed that the newly designed endoscope was capable of visualizing a target installed on an inner surface of the mock system. Also confirmed through in vivo tests using swine was that we could observe bifurcation in descending aorta, e.g., left renal artery, without stopping off the blood stream. © 2011 IEEE

Steroids-producing nodules: a two-layered adrenocortical nodular structure as a precursor lesion of cortisol-producing adenoma

コルチゾール産生腫瘍の前駆病変を世界で初めて発見--副腎腫瘍の発生メカニズムの解明と副腎皮質疾患の治療への応用に期--京都大学プレスリリース. 2024-04-03.Background: The human adrenal cortex consists of three functionally and structurally distinct layers; zona glomerulosa, zona fasciculata (zF), and zona reticularis (zR), and produces adrenal steroid hormones in a layer-specific manner; aldosterone, cortisol, and adrenal androgens, respectively. Cortisol-producing adenomas (CPAs) occur mostly as a result of somatic mutations associated with the protein kinase A pathway. However, how CPAs develop after adrenocortical cells acquire genetic mutations, remains poorly understood. Methods: We conducted integrated approaches combining the detailed histopathologic studies with genetic, RNA-sequencing, and spatially resolved transcriptome (SRT) analyses for the adrenal cortices adjacent to human adrenocortical tumours. Findings: Histopathological analysis revealed an adrenocortical nodular structure that exhibits the two-layered zF- and zR-like structure. The nodular structures harbour GNAS somatic mutations, known as a driver mutation of CPAs, and confer cell proliferative and autonomous steroidogenic capacities, which we termed steroids-producing nodules (SPNs). RNA-sequencing coupled with SRT analysis suggests that the expansion of the zF-like structure contributes to the formation of CPAs, whereas the zR-like structure is characterised by a macrophage-mediated immune response. Interpretation: We postulate that CPAs arise from a precursor lesion, SPNs, where two distinct cell populations might contribute differently to adrenocortical tumorigenesis. Our data also provide clues to the molecular mechanisms underlying the layered structures of human adrenocortical tissues. Funding: KAKENHI, The Uehara Memorial Foundation, Daiwa Securities Health Foundation, Kaibara Morikazu Medical Science Promotion Foundation, Secom Science and Technology Foundation, ONO Medical Research Foundation, and Japan Foundation for Applied Enzymology

Antiphase Fermi-surface modulations accompanying displacement excitation in a parent compound of iron-based superconductors

We investigate the transient electronic structure of BaFe2As2, a parent compound of iron-based superconductors, by time- and angle-resolved photoemission spectroscopy. In order to probe the entire Brillouin zone, we utilize extreme ultraviolet photons and observe photoemission intensity oscillation with the frequency of the A1g phonon which is antiphase between the zone-centered hole Fermi surfaces (FSs) and zone-cornered electron FSs. We attribute the antiphase behavior to the warping in one of the zone-centered hole FSs accompanying the displacement of the pnictogen height, and find that this displacement is the same direction as that induced by substitution of P for As, where superconductivity is induced by a structural modification without carrier doping in this system.Comment: accepted for publication as a Rapid Commun. in PR

Development of a vascular endoscopic system for observing inner wall of large arteries for the use of endovascular intervention

金沢大学理工研究域機械工学系We have been developing an endoscopic system for observing inner wall of large arteries. The purpose of this system is to visualize the inner wall of large arteries, e.g., an aorta, without blocking off the blood stream for the use of an assistive technique for endovascular interventions such as stent-graft placement for aortic aneurysm. The technique newly introduced for this purpose was the use of intermittent high-pressure saline jet synchronized to heart beat (diastolic phase). In the previous paper [1], we reported performance of a prototype system using a commercially available bronchoscope having an outer diameter of 5mm with a biopsy channel. A discharging system for intermittent high-pressure saline jet was also constructed using a high-speed solenoid valve and a pressurizing tank. In this study, we tried to introduce a special hood (we call "Hemo-visor") on the tip of the endoscope in order to more clearly observe the target (inner wall of artery). From in vitro tests using a mock circulation system, it was confirmed that the Hemo-visor was highly effective for keeping saline solution around the endoscope tip against the blood stream, and for improving the quality of the picture obtained. © 2010 IEEE

Support vector machines as multivariate calibration model for prediction of blood glucose concentration using a new non-invasive optical method named pulse glucometry

金沢大学理工研究域機械工学系A novel optical non-invasive in vivo blood glucose concentration (BGL) measurement technique, named "Pulse Glucometry", was combined with a kernel method; support vector machines. The total transmitted radiation intensity (Iλ) and the cardiac-related pulsatile changes superimposed on Iλ in human adult fingertips were measured over the wavelength range from 900 to 1700 nm using a very fast spectrophotometer, obtaining a differential optical density (ΔOD λ) related to the blood component in the finger tissues. Subsequently, a calibration model using paired data of a family of ΔODλs and the corresponding known BGLs was constructed with support vector machines regression instead of using calibration by a conventional partial least squares regression (PLS). Our results show that the calibration model based on the support vector machines can provide a good regression for the 183 paired data, in which the BGLs ranged from 89.0-219 mg/dl (4.94-12.2 mmol/l). The resultant regression was evaluated by the Clarke error grid analysis and all data points fell within the clinically acceptable regions (region A: 93%, region B: 7%). © 2007 IEEE.