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1.
Chaos ; 33(7)2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37486665

ABSTRACT

Mobile intrinsic localized modes (ILMs) in balanced nonlinear capacitive-inductive cyclic transmission lines are studied by experiment, using a spatiotemporal driver under damped steady-state conditions. Without nonlinear balance, the experimentally observed resonance between the traveling ILM and normal modes of the nonlinear transmission line generates lattice drag via the production of a lattice backwave. In our experimental study of a balanced running ILM in a steady state, it is observed that the fundamental resonance can be removed over extended, well-defined driving frequency intervals and strongly suppressed over the complete ILM driving frequency range. Because both of these nonlinear capacitive and inductive elements display hysteresis our observation demonstrates that the experimental system, which is only partially self-dual, is surprisingly tolerant, regarding the precision necessary to eliminate the ILM backwave. It appears that simply balancing the cell dual nonlinearities makes the ILM envelope shape essentially the same at the two locations in the cell, so that the effective lattice discreteness seen by the ILM nearly vanishes.

2.
Phys Rev E ; 107(3-1): 034202, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37072939

ABSTRACT

A well-known feature of a propagating localized excitation in a discrete lattice is the generation of a backwave in the extended normal mode spectrum. To quantify the parameter-dependent amplitude of such a backwave, the properties of a running intrinsic localized mode (ILM) in electric, cyclic, dissipative, nonlinear 1D transmission lines, containing balanced nonlinear capacitive and inductive terms, are studied via simulations. Both balanced and unbalanced damping and driving conditions are treated. The introduction of a unit cell duplex driver, with a voltage source driving the nonlinear capacitor and a synchronized current source, the nonlinear inductor, provides an opportunity to design a cyclic, dissipative self-dual nonlinear transmission line. When the self-dual conditions are satisfied, the dynamical voltage and current equations of motion within a cell become the same, the strength of the fundamental, resonant coupling between the ILM and the lattice modes collapses, and the associated fundamental backwave is no longer observed.

3.
Chaos ; 32(3): 033118, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35364854

ABSTRACT

In this experimental study of the nonlinear loss mechanism between traveling localized excitation and the underlying extended normal mode spectrum for a 1D lattice, three types of cyclic, electric, nonlinear transmission lines (NLTLs) are used. They are nonlinear capacitive, inductive, and capacitive+inductive NLTLs. To maintain a robust, steady-state traveling intrinsic localized mode (ILM), a traveling wave driver is used. The ILM loses energy because of a resonance between it and the extended NLTL modes. A wake field excitation is detected directly from ILM velocity experiments by the decrease in ILM speed and by the observation of the wake. Its properties are quantified via a two-dimensional Fourier map in the frequency-wavenumber domain, determined from the measured spatial-time voltage pattern. Simulations support and extend these experimental findings. We find for the capacitive+inductive NLTL configuration, when the two nonlinear terms are theoretically balanced, the wake excitation is calculated to become very small, giving rise to supertransmission over an extended driving frequency range.

4.
Nature ; 530(7591): 453-6, 2016 Feb 25.
Article in English | MEDLINE | ID: mdl-26911781

ABSTRACT

In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations. Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of ΩIGM = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe, and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst, and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts.

5.
Horm Metab Res ; 45(12): 856-61, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23979791

ABSTRACT

The aim of this study was to investigate the differences between rats and hamsters, Two of the most widely used experimental animals, with respect to the effects of microsomal membrane solubilization on the inhibition of liver 11ß-hydroxysteroid dehydrogenase (11ß-HSDI) enzyme by bile acids. Liver microsome fractions were prepared, and the 11ß-HSDI enzymatic activity was measured using cortisone as a substrate. The substrate and various concentrations of bile acids were added to the assay mixtures. After incubation, the products were extracted and analyzed using high-performance liquid chromatography. To investigate the effect of detergent on the inhibitory effects of bile acids, we conducted inhibition tests using Triton X-100-solubilized animal liver microsomes. When solubilized microsomes were used, all bile acids inhibited 11ß-HSDI from rats and hamsters to various degrees. 7α-Hydroxycholanoic acids (cholic acid and chenodeoxycholic acid) in particular had strong inhibitory activities. In hamsters, 7ß-hydroxycholanoic acid (ursodeoxycholic acid) was the strongest inhibitor among the bile acids tested, although its effect was not very strong. When nonsolubilized microsomes were used, deoxycholic acid did not inhibit but rather enhanced the enzymatic activity in both animals. Microsomal content of cholesterol and phospholipids are significantly different between rats and hamsters. Species differences in bile acid inhibition of nonsolubilized microsomes might be reflected not only by structural difference of bile acids, which affect membrane solubilization and enzyme activity directly, but also species difference in microsomal membrane lipid content.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenases/antagonists & inhibitors , Bile Acids and Salts/pharmacology , Cell Membrane/metabolism , Microsomes, Liver/enzymology , 11-beta-Hydroxysteroid Dehydrogenases/metabolism , Animals , Cell Membrane/drug effects , Chenodeoxycholic Acid/pharmacology , Cricetinae , Male , Microsomes, Liver/drug effects , Rats , Rats, Wistar , Solubility , Species Specificity
6.
Thorax ; 63(9): 810-6, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18276722

ABSTRACT

BACKGROUND: A Th1 predominant immune response has been shown in acute hypersensitivity pneumonitis. Predominance of Th2 appears to favour the development of pulmonary fibrosis through the profibrotic process and has been described as crucial in the progression of idiopathic pulmonary fibrosis. Chronic bird fancier's lung (cBFL) can present with a histological pattern of usual interstitial pneumonia (UIP)-like lesions. Little is known about the Th1/Th2 balance in the pathogenesis of cBFL. METHODS: To evaluate the relevance of Th1-type chemokines (interferon-inducible protein, IP-10) and Th2-type chemokines (thymus- and activation-regulated chemokine, TARC) and their receptors (CXCR3 and CCR4) to the histological patterns of cBFL, 40 patients with cBFL who underwent surgical lung biopsies, 12 with acute BFL (aBFL) and 10 healthy volunteers were analysed. IP-10 and TARC levels in serum and bronchoalveolar lavage (BAL) fluid were measured by ELISA. Immunohistochemistry for CXCR3 and CCR4 was performed on surgical lung specimens. RESULTS: The ratio of TARC to IP-10 in the serum of patients with UIP-like lesions was significantly higher than in patients with cNSIP/OP-like lesions, aBFL and healthy volunteers. The ratio of CCR4 to CXCR3 in patients with UIP-like lesions was significantly higher than in those with cNSIP/OP-like lesions and fNSIP-like lesions. The ratio of CCR4-positive to CXCR3-positive cells correlated with the ratio of TARC to IP-10 in serum. CONCLUSIONS: A Th2 predominant immune response may play an important role in the development of UIP-like lesions, as already observed in idiopathic pulmonary fibrosis. A Th1 predominance may play a role in the development of cNSIP/OP-like lesions in cBFL.


Subject(s)
Bird Fancier's Lung/metabolism , Chemokine CCL17/metabolism , Chemokine CXCL10/metabolism , Pulmonary Fibrosis/metabolism , Bird Fancier's Lung/etiology , Bird Fancier's Lung/immunology , Bronchoalveolar Lavage Fluid/immunology , Female , Humans , Immunohistochemistry , Male , Middle Aged , Pulmonary Fibrosis/etiology , Pulmonary Fibrosis/immunology , Receptors, CCR4/metabolism , Receptors, CXCR3/metabolism
7.
Nature ; 440(7081): 184-6, 2006 Mar 09.
Article in English | MEDLINE | ID: mdl-16525466

ABSTRACT

The prompt gamma-ray emission from gamma-ray bursts (GRBs) should be detectable out to distances of z > 10 (ref. 1), and should therefore provide an excellent probe of the evolution of cosmic star formation, reionization of the intergalactic medium, and the metal enrichment history of the Universe. Hitherto, the highest measured redshift for a GRB has been z = 4.50 (ref. 5). Here we report the optical spectrum of the afterglow of GRB 050904 obtained 3.4 days after the burst; the spectrum shows a clear continuum at the long-wavelength end of the spectrum with a sharp cut-off at around 9,000 A due to Lyman alpha absorption at z approximately 6.3 (with a damping wing). A system of absorption lines of heavy elements at z = 6.295 +/- 0.002 was also detected, yielding the precise measurement of the redshift. The Si ii fine-structure lines suggest a dense, metal-enriched environment around the progenitor of the GRB.

8.
Phys Rev Lett ; 93(18): 185701, 2004 Oct 29.
Article in English | MEDLINE | ID: mdl-15525179

ABSTRACT

We report large-scale atomistic simulation of midrange nanoscale hydrophobic interaction, manifested by the nucleation of nanobubble between nanometer-sized hydrophobes at constrained equilibrium. When the length scale of the hydrophobes is greater than 2 nm, the nanobubble formation shows hysteresis behavior resembling the first-order transition. Calculation of the potential of mean force versus interhydrophobe distance provides a quantitative measure of the strength of the nanoscale hydrophobic interaction.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Nanotechnology/methods , Computer Simulation , Protein Folding , Proteins/chemistry , Thermodynamics , Water/chemistry
9.
Eur Neurol ; 46(1): 20-4, 2001.
Article in English | MEDLINE | ID: mdl-11455179

ABSTRACT

We examined whether autosomal dominant parkinsonism of a Japanese family, Sagamihara family, was due to the mutations of alpha-synuclein, parkin, tau, and UCH-L1, which have been reported as the causal genes for parkinsonism in other families. Restriction-enzyme digestion of polymerase-chain reaction (PCR) amplified genomic DNA fragments of alpha-synuclein exons 3 and 4 detected no point mutation. PCR-amplification of parkin exons 3, 4, 5, 6 and 7 detected no exon deletion. Direct sequencing of PCR-amplified DNA fragments of tau exons 9, 10, 12, and 13 and intron 10, and of UCH-L1 exon 4 revealed that all these exons and intron were normal including a polymorphic nucleotide substitution. These results indicated that the parkinsonism of the Sagamihara family seems not to be due to previously identified point mutations of alpha-synuclein, tau, or UCH-L1, or to exon deletion of parkin.


Subject(s)
Ligases/blood , Ligases/genetics , Nerve Tissue Proteins/blood , Nerve Tissue Proteins/genetics , Parkinsonian Disorders/blood , Parkinsonian Disorders/genetics , Thiolester Hydrolases/blood , Thiolester Hydrolases/genetics , Ubiquitin-Protein Ligases , tau Proteins/blood , tau Proteins/genetics , Exons/genetics , Female , Humans , Japan , Male , Mutation/genetics , Pedigree , Polymerase Chain Reaction , Synucleins , Ubiquitin Thiolesterase , alpha-Synuclein
10.
Breast Cancer ; 8(2): 116-24, 2001.
Article in English | MEDLINE | ID: mdl-11342984

ABSTRACT

BACKGROUND: The purpose of this study was to evaluate the diagnostic value and clinical significance of three-dimensional MR imaging of the breast in patients with mammographically detected suspicious microcalcifications. METHODS: Forty patients with suspicious microcalcifications on mammography were evaluated with three-dimensional MR imaging. MR findings were grouped mainly by distribution of abnormal enhancement (linear, focal-clumped, segmental-clumped, segmental-stippled and diffuse-stippled). These findings were compared with the mammography findings according to the criteria of the Breast Imaging Reporting and Data System (BI-RADS) and histopathologic data. RESULTS: Twenty patients had proven malignancies, most frequently ductal carcinoma in situ. For all the cases, linear (100%) and segmental-clumped type (100%) enhancement on MR imaging showed a significantly higher risk for malignancy. Diffuse stippled type (7%) and no enhancement (0%) on MR imaging indicated the lowest possibility of malignancy. 3D-MR imaging showed a sensitivity of 90%, a specificity of 95% and an overall accuracy of 93% in this study. CONCLUSIONS: Three-dimensional MR imaging of the breast can more accurately diagnose ductal carcinoma in situ. Combined with mammography, this procedure is useful for reducing the number of false-positive biopsies and helpful for deciding the better management of patients with mammographically detected suspicious microcalcifications.


Subject(s)
Breast Diseases/diagnosis , Breast/pathology , Calcinosis/diagnosis , Magnetic Resonance Imaging/methods , Adult , Aged , Breast Neoplasms/diagnosis , Carcinoma, Intraductal, Noninfiltrating/diagnosis , Diagnosis, Differential , Female , Gadolinium DTPA , Humans , Mammography , Middle Aged
11.
Nucleic Acids Res Suppl ; (1): 261-2, 2001.
Article in English | MEDLINE | ID: mdl-12836364

ABSTRACT

We report here kinetic analyses of the hydrolysis of DNA by the ATP-dependent DNase using a DNA-immobilized quartz-crystal microbalance (QCM), which enables in situ real-time monitoring both the binding of enzyme and the hydrolysis reaction on DNA strands, as mass changes.


Subject(s)
Adenosine Triphosphate/metabolism , DNA/metabolism , Deoxyribonucleases/metabolism , Quartz/chemistry , Base Sequence , Crystallization , DNA/chemistry , Hydrolysis , Kinetics , Molecular Sequence Data , Protein Binding
12.
J Biochem ; 127(2): 345-50, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10731703

ABSTRACT

A heterologous expression system of the blue copper-containing nitrite reductase from Alcaligenes xylosoxidans GIFU1051 (AxgNIR) was constructed, and the purified recombinant enzyme was characterized. All the characteristic spectroscopic properties and enzyme activity of native AxgNIR were retained in the copper-reconstituted recombinant protein expressed in Escherichia coli, indicating the correct coordination of two types of Cu (type 1 and 2) in the recombinant enzyme. Moreover, two conserved noncoordinate residues, Asp98 and His255, located near the type 2 Cu site were replaced to elucidate the catalytic residue(s) of NIR. The Asp98 residue hydrogen-bonded to the water molecule ligating the type 2 Cu was changed to Ala, Asn, or Glu, and the His255 residue hydrogen-bonded to Asp98 through the water molecule was replaced with Ala, Lys, or Arg. The catalytic rate constants of all mutants were decreased to 0.4-2% of those of the recombinant enzyme, and the apparent K(m) values for nitrite were greatly increased in the Asp98 mutants. All the steady-state kinetic data of the mutants clearly demonstrate that both Asp98 and His255 are involved not only in the catalytic reaction but also in the substrate anchoring.


Subject(s)
Copper/metabolism , Nitrite Reductases/chemistry , Nitrite Reductases/metabolism , Alcaligenes/enzymology , Amino Acid Sequence , Aspartic Acid , Binding Sites , Conserved Sequence , Histidine , Kinetics , Molecular Sequence Data , Mutation , Nitrite Reductases/genetics , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Structure-Activity Relationship
13.
Nucleic Acids Symp Ser ; (44): 187-8, 2000.
Article in English | MEDLINE | ID: mdl-12903331

ABSTRACT

To study RNA-peptide interactions, we performed an in vitro selection of RNA on a 27 MHz quartz-crystal microbalance (QCM) on which a simple R5 helix peptide was immobilized as a model of N peptide from bacteriophade lambda. The consensus sequences including a GNRA tetraloop were obtained from a random RNA pool after the 7th cycle selection.


Subject(s)
RNA-Binding Proteins/metabolism , RNA/metabolism , Amino Acid Motifs , Bacteriophage lambda/genetics , Base Sequence , Binding Sites , In Vitro Techniques , Kinetics , Nucleic Acid Conformation , RNA/chemistry , RNA/genetics , RNA-Binding Proteins/chemistry , RNA-Binding Proteins/genetics , Viral Regulatory and Accessory Proteins/chemistry , Viral Regulatory and Accessory Proteins/genetics , Viral Regulatory and Accessory Proteins/metabolism
14.
Nucleic Acids Symp Ser ; (44): 243-4, 2000.
Article in English | MEDLINE | ID: mdl-12903359

ABSTRACT

We report here binding kinetics of proliferating cell nuclear antigen (PCNA) to the dsDNA immobilized on a 27 MHz quartz-crystal microbalance. PCNA is a toroidal-shaped protein and encircles dsDNA sliding along the strand. The binding behavior of this sliding clamp protein was compared with those of other side binding proteins such as GCN4-bZIP and Zn-finger peptides.


Subject(s)
DNA/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Base Sequence , Basic-Leucine Zipper Transcription Factors , DNA/chemistry , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , G-Box Binding Factors , In Vitro Techniques , Kinetics , Nucleic Acid Conformation , Proliferating Cell Nuclear Antigen/chemistry , Protein Binding , Quartz , Solutions , Transcription Factors/chemistry , Transcription Factors/metabolism , Water , Zinc Fingers
16.
Nucleic Acids Symp Ser ; (42): 147-8, 1999.
Article in English | MEDLINE | ID: mdl-10780422

ABSTRACT

We report here kinetic analyses of DNA ligation by using a DNA-immobilized quartz-crystal microbalance (QCM), which enables in situ real-time monitoring of both the binding of ligase and ligation reaction on DNA strands, as mass changes.


Subject(s)
DNA Ligases/metabolism , Oligodeoxyribonucleotides/metabolism , Bacteriophage T4/enzymology , Base Sequence , Kinetics , Microchemistry/methods , Oligodeoxyribonucleotides/chemistry , Quartz
17.
Nucleic Acids Symp Ser ; (42): 193-4, 1999.
Article in English | MEDLINE | ID: mdl-10780445

ABSTRACT

A highly sensitive 27 MHz quartz-crystal microbalance (QCM) was applied as a device of dsDNA in vitro selection. When GCN4-bZIP peptides were immobilized on the small Au electrode of the QCM, dsDNAs having TGACTCA sequences could be mainly selected from DNA library having a 15-bp random region, which was consistent with the sequence observed by X-ray crystallography.


Subject(s)
DNA/chemistry , Fungal Proteins/chemistry , Nucleic Acid Conformation , Protein Kinases/chemistry , Saccharomyces cerevisiae Proteins , Amino Acid Sequence , Base Sequence , Crystallography, X-Ray , DNA/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Fungal Proteins/metabolism , Kinetics , Leucine Zippers , Models, Molecular , Molecular Sequence Data , Polymerase Chain Reaction , Protein Kinases/metabolism
18.
Anal Chem ; 70(7): 1288-96, 1998 Apr 01.
Article in English | MEDLINE | ID: mdl-15779144

ABSTRACT

A highly sensitive 27-MHz quartz-crystal microbalance, on which a 10-30-mer oligonucleotide was immobilized as a probe molecule, was employed to detect hybridization of complementary oligonucleotides in aqueous solution. From frequency decreases (mass increases due to the hybridization) with passage of time, kinetic parameters such as association constants (K(a)) and binding and dissociation rate constants (k(1) and k(-1)) could be obtained, as well as binding (hybridization) amount at the nanogram level (delta m). Kinetic studies were carried out by changing various parameters: (i) the immobilization method of a probe oligonucleotide on Au electrode, (ii) number of mismatching bases in sequences of target oligonucleotides, (iii) length of both probe and target oligonucleotides, (iv) hybridization temperature, and (v) ionic strength in solution. The obtained results were compared with those obtained by a surface plasmon resonance method using a BIAcore system.


Subject(s)
DNA/chemistry , Nucleic Acid Hybridization/methods , Oligonucleotides/chemistry , Avidin/chemistry , Base Pairing , Biotin/chemistry , Kinetics , Oligonucleotide Probes/chemistry , Osmolar Concentration , Quartz/chemistry , Temperature
19.
J Oral Maxillofac Surg ; 53(1): 24-6; discussion 26-7, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7799117

ABSTRACT

PURPOSE: To evaluate the possibility of using sevoflurane for inhalation sedation. PATIENTS AND METHODS: Thirty-five volunteers were divided randomly into two groups: sevoflurane group (n = 20) and nitrous oxide (N2O) group (n = 15). At the beginning of the sedation they all inhaled 100% O2, then a 0.1 minimum alveolar concentration (MAC) of sevoflurane or 10% N2O with oxygen, a 0.2 MAC of sevoflurane or 20% N2O with oxygen, and 0.3 MAC of sevoflurane or 30% N2O with oxygen for 10 minutes each. RESULTS: The respiratory and cardiovascular functions were stable during inhalation of the gas mixtures. There were five negative comments about breathing N2O, but none about breathing sevoflurane. CONCLUSION: All subjects in the sevoflurane group stated they would be willing to submit to the same inhalation procedure again.


Subject(s)
Anesthesia, Dental , Anesthesia, Inhalation , Anesthetics, Inhalation/administration & dosage , Ethers/administration & dosage , Methyl Ethers , Nitrous Oxide/administration & dosage , Blood Pressure/drug effects , Electrocardiography/drug effects , Female , Heart/drug effects , Heart Rate/drug effects , Humans , Lung/drug effects , Male , Oxygen/administration & dosage , Patient Satisfaction , Respiration/drug effects , Sevoflurane , Tidal Volume/drug effects
20.
Gan To Kagaku Ryoho ; 21 Suppl 4: 471-6, 1994 Dec.
Article in Japanese | MEDLINE | ID: mdl-7802452

ABSTRACT

We attempted to instruct the outpatients with malignant liver tumor (metastatic liver cancer and advanced hepatocellular carcinoma) who received intermittent arterial infusion chemotherapy using implanted reservoir to detach the devices for arterial infusion by themselves at home. All patients who received our instruction could master self-detachment at home, which shortened the hospitalized day. And patients' desire for this treatment promoted with improvement of the recognition of their families to participate in treatment together. We experienced no trouble which disturb the treatment. This methods was considered to promote the improvement of QOL of these patients.


Subject(s)
Ambulatory Care , Carcinoma, Hepatocellular/drug therapy , Home Infusion Therapy , Infusion Pumps, Implantable , Liver Neoplasms/drug therapy , Carcinoma, Hepatocellular/secondary , Female , Home Care Services, Hospital-Based , Humans , Infusions, Intra-Arterial , Liver Neoplasms/pathology , Male , Self Administration
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