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1.
Nat Commun ; 11(1): 4138, 2020 Aug 18.
Article in English | MEDLINE | ID: mdl-32811820

ABSTRACT

Charge acceleration during an intense light field application to solids attracts much attention as elementary processes in high-harmonic generation and photoelectron emission. For manipulating such attosecond dynamics of charge, carrier-envelope-phase (CEP: relative phase between carrier oscillation of light field and its envelope function) control has been employed in insulators, nanometal and graphene. In superconducting materials, collective control of charge motion is expected because of its strongly coherent nature of quasi-particles. Here we report that, in a layered organic superconductor, a non-linear petahertz current driven by a single-cycle 6 femtosecond near infrared field shows up as second harmonic generation (SHG), which is in contrast to the common belief that even harmonics are forbidden in the centrosymmetric system. The SHG represents a CEP sensitive nature and an enhancement near the superconducting temperature. The result and its quantum many-body analysis indicate that a polarized current is induced by non-linear acceleration of charge, which is amplified by superconducting fluctuations. This will lead to petahertz functions of superconductors and of strongly correlated systems.

2.
J Phys Condens Matter ; 25(46): 465603, 2013 Nov 20.
Article in English | MEDLINE | ID: mdl-24158705

ABSTRACT

We theoretically investigate charge order and nonlinear conduction in the quasi-two-dimensional organic conductor ß-(meso-DMBEDT-TTF)2PF6 (DMBEDT-TTF=dimethylbis(ethylenedithio)tetrathiafulvalene). Within the Hartree-Fock approximation, we study the effects of structural distortion on the experimentally observed checkerboard charge order and its bias-induced melting by using an extended Hubbard model with Peierls- and Holstein-types of electron-lattice interactions. The structural distortion is important in realizing the charge order. The current-voltage characteristics obtained by a nonequilibrium Green's function method indicate that a charge-ordered insulating state changes into a conductive state. Although the charge order and lattice distortions are largely suppressed at a threshold voltage, they remain finite even in the conductive state. We discuss the relevance of the results to experimental observations, especially to a possible bias-induced metastable state.

3.
Phys Rev Lett ; 105(24): 246402, 2010 Dec 10.
Article in English | MEDLINE | ID: mdl-21231538

ABSTRACT

Ultrafast dynamics of the light-matter interaction in a charge-ordered molecular insulator α-(BEDT-TTF)2I3 were studied by pump-probe spectroscopy using few-optical-cycle infrared pulses (pulse width 12 fs). Coherent oscillation of the correlated electrons and subsequent Fano destructive interference with intramolecular vibration were observed in time domain; the results indicated a crucial role for electron-electron interplay in the light-matter interaction leading to the photoinduced insulator-to-metal transition. The qualitative features of this correlated electron motion were reproduced by calculations based on exact many-electron-phonon wave functions.

4.
Dig Liver Dis ; 40(5): 371-8, 2008 May.
Article in English | MEDLINE | ID: mdl-18083083

ABSTRACT

BACKGROUND: Liver fibrosis is the main predictor of the progression of nonalcoholic fatty liver disease. Transient elastography (FibroScan), which measures liver stiffness, is a novel, noninvasive method to assess liver fibrosis. AIM: We investigated the usefulness of liver stiffness measurement in the evaluation of liver fibrosis in nonalcoholic fatty liver disease patients. STUDY POPULATION: A total of 97 nonalcoholic fatty liver disease patients. METHODS: Transient elastography was performed for liver stiffness measurement in 97 nonalcoholic fatty liver disease patients. And the relationship between histological parameters and liver stiffness measurement was studied by multivariate analysis. Moreover, we investigated the relationship between liver stiffness measurement and the serum levels of hyaluronic acid and type IV collagen 7s domain. RESULTS: The liver stiffness was well correlated with the stage of liver fibrosis (Kruskal-Wallis test p < 0.0001). The areas under the receiver-operating characteristic curves were 0.927 for > or = F1, 0.865 for > or = F2, 0.904 for > or = F3, 0.991 for > or = F4. Only fibrosis stage was correlated significantly with liver stiffness measurement by multiple regression analysis. Liver stiffness was also strongly correlated with the serum levels of type IV collagen 7s domain (r = 0.525, p < 0.0001) and hyaluronic acid (r = 0.457, p < 0.0001). CONCLUSIONS: Our results show a significant correlation between liver stiffness measurement and fibrosis stage in nonalcoholic fatty liver disease patients, as confirmed by the results of liver biopsy, which remains the gold standard for evaluation of the severity of liver fibrosis in patients with nonalcoholic steatohepatitis.


Subject(s)
Fatty Liver/complications , Liver Cirrhosis/diagnosis , Liver/physiopathology , Biopsy , Collagen Type VII/blood , Disease Progression , Elasticity , Elasticity Imaging Techniques/methods , Fatty Liver/diagnosis , Fatty Liver/physiopathology , Female , Follow-Up Studies , Humans , Liver/pathology , Liver Cirrhosis/etiology , Liver Cirrhosis/physiopathology , Male , Middle Aged , Prospective Studies , ROC Curve , Severity of Illness Index , Tomography, X-Ray Computed
5.
Kyobu Geka ; 56(2): 129-32, 2003 Feb.
Article in Japanese | MEDLINE | ID: mdl-12635323

ABSTRACT

The first case was a 55-year-old man, who suffered by a rope while driving his motor bicycle. On 7th day after injury, tracheotomy was scheduled due to progressive dyspnea. Following intubation of a endotracheal tube, his trachea was ruptured. The second case was a 16-year-old man, who was stabbed his trachea with a sword by his mother. His trachea completely separated following coughing during the examination of bronchoscopy. For 2 cases, we immediately excised their necks for tracheotomy but couldn't find their distal portion of trachea, because they were migrated into the mediastinum. We inserted our finger into the mediastinum for exploration and could draw it back. Both case's postoperative course was uneventful. Whenever cervical trachea is completely separated, tracheal distal end may be pulled down into the mediastinum. We invited new technique of exploration for migrated trachea using our finger.


Subject(s)
Choristoma/surgery , Mediastinal Diseases/surgery , Trachea/injuries , Trachea/surgery , Wounds, Penetrating/surgery , Adolescent , Dyspnea/etiology , Humans , Intubation, Intratracheal , Male , Middle Aged , Tracheotomy/methods
6.
Forensic Sci Int ; 122(1): 48-51, 2001 Oct 15.
Article in English | MEDLINE | ID: mdl-11587865

ABSTRACT

A suicide caused by ingestion of multiple psychoactive drugs is reported. A 42-year-old man with a history of psychosis was found dead in a blood pool in his room. The forensic autopsy revealed two stab wounds on his chest. However, these wounds could not explain the cause of death. Eighty-six tablets were found in his stomach. Four psychoactive drugs; clocapramine (CC), chlorpromazine (CP), promethazine (PM) and clotiazepam (CT) were detected in blood and tissues. The concentrations of CC, CP, PM and CT in the femoral vein (FV) blood were 0.39, 0.61, 1.23 and 0.09 microg/ml, respectively. The cause and manner of death were attributed to suicidal multiple psychoactive drug poisoning. Postmortem drug redistribution showed great site-dependent variations with the lowest level in the FV blood. Remarkable variations were observed in CC, CP and PM, but not in CT compared to other three drugs. The variations were dependent on the volume of distribution (Vd) of the drugs. Our human case has demonstrated drugs with higher Vd values showed higher degree of postmortem redistribution of the drug and vice versa.


Subject(s)
Dibenzazepines/poisoning , Psychotropic Drugs/poisoning , Suicide , Adult , Chromatography, High Pressure Liquid , Humans , Male , Psychotropic Drugs/blood , Psychotropic Drugs/pharmacokinetics , Tissue Distribution
7.
J Clin Forensic Med ; 8(4): 222-4, 2001 Dec.
Article in English | MEDLINE | ID: mdl-15274962

ABSTRACT

The body of a 61-year-old woman was found in the morning lying near a wire fence at her farm where she was cutting grass using a motor-powered strimmer. Autopsy revealed a laceration of the heart apex, haemopericardium and left haemothorax caused by a U-shaped wire projectile which was found lodged in the left thoracic cavity. The mechanistic analysis of the injuries and manner of death, however, were conclusive after a scene visit following the autopsy. The farm was surrounded by a wire fence to prevent wild pigs from entering in. The wire projectile was cut by unshielded blade of the strimmer and struck her chest. This case represents an unusual accidental fatality and indicates the need for improved user education and safety when using such implements. This case also reemphasizes scene investigation as an important part of medicolegal autopsy for proper determination of mechanisms of injuries and precise manner of death. We hope this report will increase awareness and alert the general public to the dangers of the grass strimmer operated without proper safety precautions.

8.
Phys Rev Lett ; 84(13): 2830-2, 2000 Mar 27.
Article in English | MEDLINE | ID: mdl-11018953

ABSTRACT

The polymeric molecule can exhibit a new photoinduced phenomenon where the electric dipole of the molecule with a bipolaron is reversed by absorbing one photon. This photoinduced polarization inversion occurred in a single molecule is an ultrafast process with a relaxation time of 200 fs.

9.
Med Sci Law ; 39(1): 82-4, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10087848

ABSTRACT

A case of decapitation of a vehicle passenger in an accident on a highway is reported. Evaluation of roadside evidence and the deceased's injuries revealed that the victim was partially ejected from a broken passenger-side window as the vehicle spun out of control, decapitation being due to the impact of his head against a barrier stanchion on the shoulder of the road. An unfastened seat-belt, high-speed driving and the construction of the road barrier were contributory factors.


Subject(s)
Accidents, Traffic/legislation & jurisprudence , Craniocerebral Trauma/pathology , Neck Injuries/pathology , Adult , Autopsy/legislation & jurisprudence , Female , Humans , Male
10.
J Clin Forensic Med ; 5(4): 183-6, 1998 Dec.
Article in English | MEDLINE | ID: mdl-15335516

ABSTRACT

A 54-year-old man was found dead in the driver's seat of his vehicle on a winter's day. Investigations of the vehicle revealed that the engine was running, and the car heater was left on with the maximum temperature and velocity. The body was found excessively sweating. Rectal temperature of the body was 43 degrees C at 10 h post mortem. In autopsy, several superficial skin burns were observed on the face, the shoulders and the legs. The lungs were heavily congested and hemorrhagic. The liver showed typical alcohol-induced micronodular cirrhosis. The alcohol concentrations were 0.17% in the blood of both the left and the right heart, 0.17% in the femoral-vein blood, 0.21% in the bladder urine and 0.34% in the gastric contents. A reconstruction experiment demonstrated that the temperature inside the vehicle rose rapidly and reached 50-58 degrees C in 3 h. Animal experiments showed that the temperature threshold for rats to succumb to heat was between 40 and 45 degrees C. This case shows that heat stroke in a vehicle can occur in adults with chronic diseases or alcoholism, such as in this particular case, even in the winter.

11.
Nihon Hoigaku Zasshi ; 51(1): 56-62, 1997 Feb.
Article in Japanese | MEDLINE | ID: mdl-9078843

ABSTRACT

The World Police Medical-Officers in Clinical Forensic Medicine (WPMO) is an international conference on practice of forensic medicine and clinical forensic medicine to be taken place every three years. Its 4th international conference (WPMO-1996-KUMAMOTO) was held on 19-23 August 1996 in Kumamoto, Japan. A total of 294 participants, 89 overseas from 18 countries and 205 domestic, were attended. Four plenary lectures and 67 free papers were presented in the conference. Such social programs as welcome reception, one-day-tour, citizen's home visit, banquet etc were carried out. The two plenary entitled 'Current Status of Practice of Forensic Medicine in U.S.A.' by Prof. Thomas T. Noguchi and 'Origins and Development of the Police Surgeon Services in U.K.' by Dr. Reginald A. Bunting were tape-recorded and presented in this report as references of future activities of forensic medicine in Japan.


Subject(s)
Coroners and Medical Examiners , Forensic Medicine , International Cooperation , Japan
14.
Phys Rev B Condens Matter ; 50(5): 2899-2920, 1994 Aug 01.
Article in English | MEDLINE | ID: mdl-9976533
15.
16.
Clin Endocrinol (Oxf) ; 39(5): 557-60, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8252745

ABSTRACT

OBJECTIVES: We have reported that 19-hydroxyandrostenedione (19-OH-A-dione) functions as an amplifier of the sodium-retaining and hypertensive action of aldosterone. We therefore measured 19-hydroxyandrostenedione in hypertensive patients. PATIENTS AND MEASUREMENTS: We studied 53 normal male control subjects and 63 male patients with essential hypertension (48 patients with normal renin essential hypertension and 15 patients with high renin essential hypertension). Plasma 19-OH-A-dione levels were measured by RIA. RESULTS: Plasma 19-OH-A-dione concentrations in control subjects and patients with normal and high renin essential hypertension were 115 +/- 46 (mean +/- SD), 112 +/- 49 and 201 +/- 79 pmol/l, respectively. Patients with high renin essential hypertension showed significantly higher 19-OH-A-dione concentrations than did control subjects. The evaluation of the correlation between plasma 19-OH-A-dione concentrations and plasma renin activity revealed that plasma 19-OH-A-dione concentrations in hypertensive subjects rose gradually with an increase in plasma renin activity. Therefore, a significant correlation was found between plasma renin activity and plasma 19-OH-A-dione (r = 0.586, P < 0.001). In contrast, in control subjects, no significant correlation was found between plasma renin activity and plasma 19-OH-A-dione (r = 0.059, P > 0.05). CONCLUSIONS: The secretion of 19-OH-A-dione from the adrenal cortex is under the control of the renin-angiotensin system in hypertensives but not in normotensives.


Subject(s)
Androstenedione/analogs & derivatives , Hypertension/blood , Renin/blood , Adult , Androstenedione/blood , Humans , Male , Middle Aged , Radioimmunoassay
17.
Phys Rev B Condens Matter ; 48(9): 6680-6682, 1993 Sep 01.
Article in English | MEDLINE | ID: mdl-10009231
18.
Phys Rev B Condens Matter ; 48(5): 3349-3355, 1993 Aug 01.
Article in English | MEDLINE | ID: mdl-10008762
19.
Forensic Sci Int ; 59(2): 177-84, 1993 May.
Article in English | MEDLINE | ID: mdl-8330810

ABSTRACT

Site and temporal changes in tranylcypromine (TCP) and lithium concentrations in blood were studied in a human poisoning case. Blood samples from peripheral vessels and six central vessels were obtained at 0, 6, 24, 48 and 72 h after starting the autopsy. Nine tissue samples were obtained on completion. TCP showed preferential concentration in liver (2.21 micrograms/g) and brainstem (2.46 micrograms/g). There was a moderate post mortem redistribution phenomenon with TCP concentrations lowest in peripheral blood (0.17 micrograms/ml) at 0 h and highest in central vessels at 24 h (0.52 micrograms/ml). At 72 h blood TCP concentrations fell below those at 0 time but the samples showed marked putrefactive changes. Control blood samples spiked with TCP and incubated for 48 h at 37 degrees C showed a 58% fall in drug concentration. By contrast with TCP, lithium, which has a small Vd (0.8 l/kg) and is chemically stable, did not show this pattern of change in blood concentration. The site and temporal differences in TCP concentration in blood can be explained by the competing effects of post mortem redistribution and drug degradation. Redistribution is an early post mortem phenomenon characterised by diffusion, along a concentration gradient, from drug reservoirs in solid organs into adjacent blood vessels. Drug degradation is a later phenomenon associated with putrefactive change.


Subject(s)
Lithium/blood , Lithium/poisoning , Postmortem Changes , Tranylcypromine/blood , Tranylcypromine/poisoning , Drug Overdose/blood , Drug Overdose/metabolism , Drug Overdose/pathology , Forensic Medicine , Humans , Lithium/analysis , Lithium/pharmacokinetics , Male , Middle Aged , Organ Size , Time Factors , Tissue Distribution , Tranylcypromine/analysis , Tranylcypromine/pharmacokinetics
20.
Phys Rev B Condens Matter ; 47(18): 12059-12088, 1993 May 01.
Article in English | MEDLINE | ID: mdl-10005378
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