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1.
Phys Rev Lett ; 126(21): 217202, 2021 May 28.
Article in English | MEDLINE | ID: mdl-34114835

ABSTRACT

CeIrSn with a quasikagome Ce lattice in the hexagonal basal plane is a strongly valence fluctuating compound, as we confirm by hard x-ray photoelectron spectroscopy and inelastic neutron scattering, with a high Kondo temperature of T_{K}∼480 K. We report a negative in-plane thermal expansion α/T below 2 K, which passes through a broad minimum near 0.75 K. Volume and a-axis magnetostriction for B∥a are markedly negative at low fields and change sign before a sharp metamagnetic anomaly at 6 T. These behaviors are unexpected for Ce-based intermediate valence systems, which should feature positive expansivity. Rather they point towards antiferromagnetic correlations at very low temperatures. This is supported by muon spin relaxation measurements down to 0.1 K, which provide microscopic evidence for a broad distribution of internal magnetic fields. Comparison with isostructural CeRhSn suggests that these antiferromagnetic correlations emerging at T≪T_{K} result from geometrical frustration.

2.
Phys Rev Lett ; 123(6): 067201, 2019 Aug 09.
Article in English | MEDLINE | ID: mdl-31491187

ABSTRACT

Acoustic signatures of the single-site quadrupolar Kondo effect in Y_{0.966}Pr_{0.034}Ir_{2}Zn_{20} are presented. The elastic constant (C_{11}-C_{12})/2, corresponding to the Γ_{3}(E)-symmetry electric-quadrupolar response, reveals a logarithmic temperature dependence of the quadrupolar susceptibility in the low-magnetic-field region below ∼0.3 K. Furthermore, the Curie-type divergence of the elastic constant down to ∼1 K indicates that the Pr ions in this diluted system have a non-Kramers ground-state doublet. These observations evidence the single-site quadrupolar Kondo effect, as previously suggested based on specific-heat and electrical-resistivity data.

3.
Phys Rev Lett ; 121(7): 077206, 2018 Aug 17.
Article in English | MEDLINE | ID: mdl-30169096

ABSTRACT

Electrical resistivity ρ(T) and specific heat C(T) measurements have been made on the diluted 4f^{2} system Y(Pr)Ir_{2}Zn_{20}. Both data of ρ and magnetic specific heat C_{m} per Pr ion are well scaled as a function of T/T_{0}, where T_{0} is a characteristic temperature of non-Fermi-liquid (NFL) behaviors. Furthermore, the temperature dependences of ρ and C_{m}/T agree with the NFL behaviors predicted by the two-channel Kondo model for the strong coupling limit. Therefore, we infer that the observed NFL behaviors result from the single-site quadrupole Kondo effect due to the hybridization of the 4f^{2} states with multichannel conduction electrons.

4.
J Phys Condens Matter ; 24(29): 294207, 2012 Jul 25.
Article in English | MEDLINE | ID: mdl-22773390

ABSTRACT

We performed electrical resistivity ρ, magnetic susceptibility χ, specific heat C and electron diffraction measurements on single-crystalline samples of PrT2Zn20 (T = Ru, Rh and Ir). The three compounds show the Van Vleck paramagnetic behavior, indicating the nonmagnetic crystalline electric field (CEF) ground states. A Schottky-type peak appears at around 14 K, irrespective of the T element, which can be moderately reproduced by a doublet­triplet model. For T = Ru, a structural transition occurs at Ts = 138 K, below which no phase transition appears down to 0.04 K. On the other hand, for T = Ir, antiferroquadrupole (AFQ) ordering arising from the nonmagnetic Γ3 doublet takes place at TQ = 0.11 K. For T = Rh, despite a structural transition between 170 and 470 K, the CEF ground state is still the non-Kramers Γ3 doublet. However, no phase transition due to the Γ3 doublet was observed even down to 0.1 K.

5.
Phys Rev Lett ; 106(17): 177001, 2011 Apr 29.
Article in English | MEDLINE | ID: mdl-21635057

ABSTRACT

An antiferroquadrupolar ordering at T(Q)=0.11 K has been found in a Pr-based superconductor PrIr(2)Zn(20). The measurements of specific heat and magnetization revealed the non-Kramers Γ(3) doublet ground state with the quadrupolar degrees of freedom. The specific heat exhibits a sharp peak at T(Q)=0.11 K. The increment of T(Q) in magnetic fields and the anisotropic B-T phase diagram are consistent with the antiferroquadrupolar ordered state below T(Q). The entropy release at T(Q) is only 20% of Rln2, suggesting that the quadrupolar fluctuations play a role in the formation of the superconducting pairs below T(c)=0.05 K.

6.
Phys Rev Lett ; 102(9): 096403, 2009 Mar 06.
Article in English | MEDLINE | ID: mdl-19392540

ABSTRACT

The local effect of an interstitial hydrogenlike particle on localized f electrons was studied in PrPb3 by means of micro+ spin rotation and relaxation. Spontaneous micro+ spin precession with harmonic frequencies was observed for the first time in f electron compounds. We demonstrate that the signal is derived from a coupling between the micro+ spin and the hyperfine-enhanced nuclear spin of nearest neighbor (NN) 141Pr with Ising-like anisotropy. The signal also suggests a marked suppression of spin dynamics of the NN 141Pr in comparison with that of the bulk 141Pr. These facts strongly indicate modification of the f electronic state due to the interstitial charged particle.

7.
Phys Rev Lett ; 94(19): 197201, 2005 May 20.
Article in English | MEDLINE | ID: mdl-16090203

ABSTRACT

Neutron diffraction measurements have been performed on the cubic compound PrPb(3) in a [001] magnetic field to examine the quadrupolar ordering. Antiferromagnetic components with q = (1/2 +/- delta 1/2 0), (1/2 1/2 +/- delta 0) (delta approximately 1/8) are observed below the transition temperature T(Q) (0.4 K at H = 0) whose amplitudes vary linear with H and vanish at zero field, providing the first evidence for a modulated quadrupolar phase. For H < 1 T, a nonsquare modulated state persists even below 100 mK suggesting quadrupole moments associated with a Tau(3) doublet ground state to be partially quenched by hybridization with conduction electrons.

8.
J Vet Med Sci ; 61(8): 961-4, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10487241

ABSTRACT

In order to obtain available biochemical parameters related to the marbling score (MS), by which the meat was graded from 1 to 12 in Japan, serum biochemical values were examined in 13 Japanese Black steers during the fattening stages. The steers were divided into high MS (8-11) and low MS (4-5) groups and the fattening stage was also divided into 4 stages according to their feed contents; Stage I (11-13 month-old; 0-4 months after the fattening (af)), II (5-9 months af), III (10-14 months af), and IV (15-20 months af). High MS group showed significantly higher levels in glucose and urea nitrogen (at Stage I), albumin/globulin ratio (at Stage II), and magnesium (at Stage I and III), and lower level in vitamin A (at Stage III) than low MS group. These biochemical parameters, indicating conditions of steers during the fattening stages, are considered to have a possibility related to MS in fattening steers.


Subject(s)
Biomarkers/blood , Cattle/blood , Meat/standards , Animals , Japan , Male , Quality Control
9.
J Chromatogr A ; 798(1-2): 125-30, 1998 Mar 06.
Article in English | MEDLINE | ID: mdl-9542134

ABSTRACT

The rapid and simple determination of fatty vitamins (vitamins A and E) in serum by high-performance liquid chromatography with a column-switching technique was investigated. The dilution of serum with an aqueous solution containing surfactant and organic solvent and the use of an aqueous solution with organic solvent as a sample pretreatment were an effective means of improving the sample recovery. To prevent sample decomposition during storage, the addition of an antioxidant reagent into the diluent was required. Under the optimal conditions, the relative standard deviation (R.S.D.) values against the standard samples were 1.12% (16.7 I.U./dl), 0.25% (333 I.U./dl) for vitamin A, and 1.02% (0.43 microgram/ml), 0.45% (8.5 micrograms/ml) for vitamin E, respectively. The relative coefficients (r2) between the sample amounts in serum and the peak areas were 1.0000 in the range from 16.7 to 667 I.U./dl (for vitamin A) and 0.9998 from 0.434 to 17.46 micrograms/ml (for vitamin E). The recoveries of vitamins from spiked serums were ca. 100% (vitamin A) and ca. 86% (vitamin E), respectively. By the combination of an on-line deproteination column and diluting solution, the simple and rapid determination of fatty vitamins could be routinely achieved in 18-min intervals.


Subject(s)
Chromatography, High Pressure Liquid/methods , Surface-Active Agents , Vitamin A/blood , Vitamin E/blood , Drug Stability , Edetic Acid , Humans , Pyrogallol , Reproducibility of Results , Solvents
10.
J Vet Med Sci ; 60(1): 101-2, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9492367

ABSTRACT

Significant decrease of serum vitamin A (V.A) level in 4 out of 5 Japanese Black beef steers on day 7 after introduction was described in the present study. The feeder steers were fed the diets containing much more V.A than they required. In the farm where they were introduced, the productivity was high and the frequency was low in bovine cases of death and disease. The herd management; i.e. feeding method and environment of the farm were properly arranged. Results obtained from blood serum analyses revealed that health and nutritional status of the feeder steers were good on the day of introduction. The feeder steers, clinically healthy on the day of introduction, manifested mild bronchitis and diarrhea on days 2 and 10 after introduction, respectively, and slightly decreased dietary intake on both days. Serum V.A levels of the feeder steers were within the normal range. However, significantly decreased serum V.A level was detected in 4 feeder steers out of 5 on day 7 after introduction. This may be attributed to stress-increased V.A consumption rather than the decreased V.A intake.


Subject(s)
Animal Husbandry , Cattle/blood , Vitamin A/blood , Animal Feed , Animals , Electrolytes/blood , Enzymes/blood , Food, Fortified , Male , Meat , Nutritional Status , Orchiectomy , Time Factors
11.
Jpn J Antibiot ; 51(11): 625-81, 1998 Nov.
Article in Japanese | MEDLINE | ID: mdl-10028453

ABSTRACT

A thirteen-week intravenous repeated dose toxicity study of T-3762, parenteral quinolone antimicrobial agent, and four-week recovery test was carried out in male and female cynomolgus monkeys at dosages of 26, 52 and 104 mg/kg. The following results were obtained. 1) There was no death of animals during administration period at any dose levels. In general signs, there was no abnormality at any dose levels. 2) In appetite, body weights and ophthalmological examination, there was no abnormality attributable to the treatment. 3) In urinalysis, hematological examination and biochemical examination, there was no abnormality attributable to the treatment. 4) In organ weights, macroscopic findings and histopathological findings, there was no abnormality attributable to the treatment. 5) From these results in this study, no-toxic dose level of T-3762 for cynomolgus monkeys is considered over 104 mg/kg.


Subject(s)
Anti-Infective Agents/toxicity , Fluoroquinolones , Animals , Anti-Infective Agents/administration & dosage , Body Weight/drug effects , Eating/drug effects , Female , Injections, Intravenous , Macaca fascicularis , Male , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Time Factors
12.
Jpn J Antibiot ; 51(10): 583-99, 1998 Oct.
Article in Japanese | MEDLINE | ID: mdl-9914950

ABSTRACT

Single dose intravenous toxicity studies of T-3762, a novel parenteral quinolone antimicrobial agent, were conducted in rats, dogs and monkeys. The following results were obtained. 1. In the rat study, all males and females given 260 mg/kg survived and all males and 3 of 5 females given 391 mg/kg died. Approximate lethal doses in male and female rats were between 260 and 391 mg/kg. In survived animals, decrease in locomotor activity and irregular respiration were observed. These clinical signs were recovered within 1 hour after dosing. In female rats given 260 mg/kg, no abnormalities were observed in general signs. In dead animals, decrease in locomotor activity, irregular respiration, staggering gait and tonic convulsion were observed and died within about 90 minutes after dosing. Macroscopic examinations in dead animals showed dark red discoloration in lung and had white foamy liquid in trachea. In histopathological examinations of dead animals, congestion, hemorrhage and edema were observed in lung. 2. In the dog study, 2 animals given 260 mg/kg survived and 2 animals given 521 mg/kg died. Approximate lethal dose in dogs was between 260 and 521 mg/kg. In the 260 and 521 mg/kg groups, decrease in locomotor activity, lateral position, vomiting, salivation and decrease in body temperature were observed. In the 521 mg/kg group, one animal died at 4 minutes and another 7 days after dosing. Histopathological examinations in 2 dead animals showed congestion or hemorrhage in heart, lung, liver, kidney, spleen and digestive tract. Erosion and necrosis at cartilage layer and cluster of chondrocyte were observed in scapular fossa and head of humerus in the 260 and 561 mg/kg groups. 3. In the monkey study, 2 animals given 260 mg/kg survived and 2 animals given 520 mg/kg died. Approximate lethal dose in monkeys was between 260 and 520 mg/kg. In the 260 mg/kg group, soft feces was observed. In the 520 mg/kg group, paleness mucosa of oral cavity, muscle weakness, mydriasis and dyspnea were observed and animals died within 4 minutes after dosing. Macroscopic and histopathological examinations in 2 dead animals showed congestion in lung, liver and kidney.


Subject(s)
Anti-Infective Agents/toxicity , Fluoroquinolones , Alanine Transaminase/blood , Animals , Anti-Infective Agents/administration & dosage , Aspartate Aminotransferases/blood , Cartilage, Articular/drug effects , Dogs , Dose-Response Relationship, Drug , Female , Injections, Intravenous , Kidney/drug effects , Lethal Dose 50 , Liver/drug effects , Macaca fascicularis , Male , Motor Activity/drug effects , Mouth Mucosa/drug effects , Rats , Rats, Sprague-Dawley , Respiration/drug effects , Respiratory System/drug effects
13.
J Vet Med Sci ; 59(10): 873-7, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9362034

ABSTRACT

Few reference values for use in metabolic profile tests for the maintenance of high productivity and the prevention of production diseases have been reported in Japanese Black beef cattle. To obtain basic data, 101 healthy steers at farms with high productivity and low frequencies of disease and death in Miyazaki Prefecture, Japan, were examined for the values of their serum components in this preliminary study. At the later fattening stage (5 to 20 months after introduction), statistically significant increases were observed in the mean serum activities of lactic dehydrogenase, glutamic-oxalacetic transaminase, gamma-glutamyl transpeptidase, and creatine phosphokinase, the mean serum contents of triglyceride, total cholesterol, albumin (Alb), total protein, blood urea nitrogen, magnesium, and vitamin E, and the mean serum calcium (Ca)/inorganic phosphorus (IP) ratio, and statistically significant decreases were seen in the mean serum alkaline phosphatase activity and the mean serum contents of glucose, IP, and vitamin A. The mean serum Alb/globulin ratio and the mean serum Ca and nonesterified fatty acids contents demonstrated no statistically significant changes.


Subject(s)
Cattle Diseases/blood , Cattle Diseases/epidemiology , Cattle/blood , Cattle/growth & development , Alkaline Phosphatase/blood , Animals , Aspartate Aminotransferases/blood , Blood Glucose/analysis , Blood Proteins/analysis , Body Composition/physiology , Calcium/blood , Cattle/physiology , Cattle Diseases/mortality , Cholesterol/blood , Creatine Kinase/blood , Fatty Acids, Nonesterified/blood , Incidence , Japan/epidemiology , L-Lactate Dehydrogenase/blood , Magnesium/blood , Male , Phosphorus/blood , Reference Values , Time Factors , Triglycerides/blood , Vitamin A/blood , Vitamin E/blood , Weight Gain/physiology , gamma-Glutamyltransferase/blood
14.
J Vet Med Sci ; 58(5): 461-4, 1996 May.
Article in English | MEDLINE | ID: mdl-8741610

ABSTRACT

Japanese Black fattening cattle in Miyazaki prefecture, Japan were examined for serum vitamin A (V. A) and vitamin E (V. E) by automatic column-switching high performance liquid chromatography with automated deproteinization. Results indicated that most Japanese Black fattening cattle in Miyazaki prefecture may be provided with V. A supplement and diets including little V. E, moderate beta-carotene and V. A during the early fattening stage, and diets including little beta-carotene, V. A and V. E during the middle and later fattening stages. Therefore, monitoring serum V. A and V. E in Japanese Black fattening cattle throughout the fattening period seems necessary for farmers in Miyazaki prefecture to avoid economic loss attributable to these deficiencies.


Subject(s)
Cattle Diseases , Cattle/blood , Vitamin A Deficiency/veterinary , Vitamin A/blood , Vitamin E Deficiency/veterinary , Vitamin E/blood , Aging/blood , Animal Feed , Animal Husbandry , Animals , Automation , Chromatography, High Pressure Liquid/methods , Food, Fortified , Japan , Reference Values , Vitamin A Deficiency/blood , Vitamin E Deficiency/blood , Weight Gain , beta Carotene
15.
J Toxicol Sci ; 19 Suppl 3: 327-75, 1994 Nov.
Article in Japanese | MEDLINE | ID: mdl-7837294

ABSTRACT

UNLABELLED: 13-week repeated dose toxicity studies were conducted on lactitol, a hepatic encephalopathy drug. In the experiment I, male and female dogs were orally treated with lactitol at doses of 0, 1.0, 2.5 and 6.25 g/kg/day for 13 weeks, followed by 4 weeks recovery period. In the experiment II, male and female dogs were orally treated with lactitol at doses of 0, 0.25, 0.50 and 1.0 g/kg/day for 13 weeks in order to require the no-toxic dose. RESULTS: 1. Soft stool and diarrhea were observed at the 0.50 g/kg group and above, and vomiting was observed at the 1.0 g/kg group and above. Increased water consumption was observed at the 6.25 g/kg group. No deaths occurred at all groups. 2. In urinalysis, increased urine volume was observed at the 6.25 g/kg group. 3. Blood chemistry showed decreased BUN at the 6.25 g/kg group. 4. There were no drug-related changes in body weight, food consumption, ophthalmological examination, electrocardiography, hematology and pathology. 5. At the end of the recovery period, all these changes observed at the end of the administration period were disappeared. Based on these results, it was considered that the no-toxic dose of lactitol is 0.25 g/kg/day.


Subject(s)
Sugar Alcohols/toxicity , Administration, Oral , Animals , Blood Chemical Analysis , Blood Urea Nitrogen , Diarrhea/chemically induced , Dogs , Drinking/drug effects , Female , Male , Sugar Alcohols/administration & dosage , Vomiting/chemically induced
16.
J Pediatr ; 106(4): 567-70, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3981310

ABSTRACT

Our study was carried out to clarify the changes in granulocyte functions and circulating immune complexes in 32 children with Kawasaki disease. Patients were divided into two groups, those with or without coronary aneurysm. In the group with coronary aneurysm, impairment of both granulocyte chemotaxis and phagocytosis was found, together with higher circulating immune complexes and normal intracellular killing activity. In the group without coronary aneurysm, impaired phagocytosis was observed, with normal granulocyte chemotaxis, circulating immune complexes, and intracellular killing activity. No correlation was observed between granulocyte chemotaxis and circulating immune complexes. Impairment of granulocyte chemotaxis and circulating immune complexes may yield pertinent information as to the degree of severity of vasculitis in Kawasaki disease.


Subject(s)
Antigen-Antibody Complex/metabolism , Chemotaxis, Leukocyte , Mucocutaneous Lymph Node Syndrome/immunology , Aneurysm/blood , Aneurysm/immunology , Child , Child, Preschool , Coronary Disease/blood , Coronary Disease/immunology , Female , Granulocytes/physiology , Humans , Infant , Male , Mucocutaneous Lymph Node Syndrome/blood , Phagocytosis , Vasculitis/blood , Vasculitis/immunology
17.
Jpn Circ J ; 48(12): 1350-3, 1984 Dec.
Article in English | MEDLINE | ID: mdl-6512943

ABSTRACT

Serum immunoglobulin levels, complement titers, circulating immune complex levels, and chemotaxis of granulocytes were evaluated in 32 patients with Kawasaki disease with or without coronary aneurysm. The group of patients with coronary aneurysm showed relatively higher levels of IgG. Regardless of the presence of coronary aneurysm, the level of IgE in the acute phase was higher than that in the convalescent phase. The level of immune complexes was higher in the group of patients with coronary aneurysm (p less than 0.05). There was a low negative correlation between immune complexes and CH50. The chemotaxis of the patients with coronary aneurysm was significantly impaired (p less than 0.01).


Subject(s)
Antigen-Antibody Complex/analysis , Chemotaxis, Leukocyte , Mucocutaneous Lymph Node Syndrome/immunology , Aneurysm/complications , Aneurysm/immunology , Child , Child, Preschool , Complement C3/analysis , Complement C4/analysis , Coronary Disease/complications , Coronary Disease/immunology , Granulocytes/immunology , Humans , Immunoglobulin A/analysis , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Mucocutaneous Lymph Node Syndrome/complications
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