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1.
J Phys Condens Matter ; 35(32)2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37137311

RESUMEN

The optical properties of pure liquid copper were investigated using density functional theory with the Quantum ESPRESSO package. The effects of structural changes were investigated by comparing the electron density of states and imaginary part of the dielectric function between the crystalline and liquid states with densities near the melting point. The results indicated that the effect of interband transitions remains in the structural changes near the melting point.

2.
Opt Express ; 30(12): 21258-21267, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224848

RESUMEN

Thermal stress effects on continuous-wave second-harmonic generation in periodically poled LiTaO3 crystals are evaluated via a numerical simulation that is based on nonlinear propagation equations and a thermal conduction equation. The thermal performance and absorption coefficients used in the numerical simulation were determined by comparison with experimental results. The results show that the thermal stress caused by a small residual absorption would restrict the maximum output power of a second-harmonic-continuous-wave laser.

3.
J Exp Biol ; 223(Pt 1)2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31822556

RESUMEN

Visual systems play a vital role in guiding the behaviour of animals. Understanding the visual information animals are able to acquire is therefore key to understanding their visually mediated decision making. Compound eyes, the dominant eye type in arthropods, are inherently low-resolution structures. Their ability to resolve spatial detail depends on sampling resolution (interommatidial angle) and the quality of ommatidial optics. Current techniques for estimating interommatidial angles are difficult, and generally require in vivo measurements. Here, we present a new method for estimating interommatidial angles based on the detailed analysis of 3D micro-computed tomography images of fixed samples. Using custom-made MATLAB software, we determined the optical axes of individual ommatidia and projected these axes into the 3D space around the animal. The combined viewing directions of all ommatidia, estimated from geometrical optics, allowed us to estimate interommatidial angles and map the animal's sampling resolution across its entire visual field. The resulting topographic representations of visual acuity match very closely the previously published data obtained from both fiddler and grapsid crabs. However, the new method provides additional detail that was not previously detectable and reveals that fiddler crabs, rather than having a single horizontal visual streak as is common in flat-world inhabitants, probably have two parallel streaks located just above and below the visual horizon. A key advantage of our approach is that it can be used on appropriately preserved specimens, allowing the technique to be applied to animals such as deep-sea crustaceans that are inaccessible or unsuitable for in vivo approaches.


Asunto(s)
Braquiuros/fisiología , Ojo Compuesto de los Artrópodos/fisiología , Agudeza Visual/fisiología , Microtomografía por Rayos X/métodos , Animales , Femenino , Masculino , Visión Ocular/fisiología
4.
Masui ; 64(4): 434-6, 2015 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-26419112

RESUMEN

A 22-year-old female with fibromyalgia (FM) was scheduled for tonsillectomy under general anesthesia. Her medication included pregabalin 300 mg x day(-1) and dantrolene 50 mg x day(-1). Anesthesia was maintained with sevoflurane-remifentanil-fentanyl. Intravenous injection of fentanyl 20 µg x hr(-1) and droperidol 100 µg x hr(-1) was continued for 24 hours. On the first postoperative day, she reported that she had slept well and had no pain. There are some perioperative problems in a patient with FM. Therefore, anesthetic managements for a patient with FM is worth reporting.


Asunto(s)
Anestesia General , Fibromialgia/cirugía , Femenino , Humanos , Dolor Postoperatorio , Tonsilectomía , Adulto Joven
5.
Masui ; 63(6): 629-35, 2014 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-24979851

RESUMEN

BACKGROUND: Few studies have examined the perioperative status of dual antiplatelet therapy and postoperative thrombotic or bleeding complication rates of patients undergoing non-cardiac surgery with recent history of coronary stent implantation. METHODS: Eight patients underwent surgery with antiplatelet therapy discontinued on both pre- and post-operative period (pre/postop group); 7 patients with only post-operative discontinuation (postop group); and 2 patients with therapy maintained (maintained group). All patients had history of coronary drug eluting stent implantation within 12 months of surgery. RESULTS: Antiplatelets were discontinued 7 days before surgery and restarted on postoperative day 7 for the pre/postop group, and on postoperative day 5 for postop group. Re-exploration due to bleeding complication was required in 1 patient in the postop group. Two or more units of red cell concentrate transfusion were required in 2 pre/postop, 3 postop, and 1 maintained group patients intraoperatively. No cardiac thrombotic complications including in-hospital stent thrombosis were observed, in line with previous reports of low stent thrombosis rates in Asian patients. CONCLUSIONS: In the present study, bleeding complications requiring transfusion were frequently observed in patients with dual antiplatelet therapy undergoing non-cardiac surgery, whereas perioperative therapy discontinuation did not trigger thrombotic complications including stent thrombosis.


Asunto(s)
Aspirina/administración & dosificación , Aspirina/efectos adversos , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Atención Perioperativa , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/efectos adversos , Hemorragia Posoperatoria/epidemiología , Hemorragia Posoperatoria/etiología , Ticlopidina/administración & dosificación , Ticlopidina/efectos adversos , Anciano , Anciano de 80 o más Años , Stents Liberadores de Fármacos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hemorragia Posoperatoria/prevención & control , Procedimientos Quirúrgicos Operativos , Trombosis/etiología , Trombosis/prevención & control , Factores de Tiempo
6.
Phys Rev Lett ; 105(7): 075004, 2010 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-20868054

RESUMEN

A three-dimensional simulation of laser-guided discharges based on percolation is presented. The model includes both local growth of a streamer due to the enhanced electric field at the streamer's tip and propagation of a leader by remote ionization such as that caused by runaway electrons. The stochastic behavior of the discharge through a preformed plasma channel is reproduced by the calculation, which shows complex path with detouring and bifurcation. The probability of guiding is investigated with respect to the ionized, conductive fraction along the channel.

7.
Opt Express ; 15(5): 2535-40, 2007 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-19532490

RESUMEN

Broad Raman-multi-frequency spectra were generated from the resonant two-color excitation of the deuterium molecule rotational Raman transition (J=0?2), using ultraviolet bi-harmonic lasers with a quartz hollow fiber. Fifty pure rotational Raman spectral lines (34 lines that have intensity within 10% of the strongest spectral line) from 230 to 290 nm were generated at a gas pressure of 30 kPa. Furthermore, vibrational-rotational Raman spectral lines of almost 300 lines from 220 to 600 nm were also generated by increasing the gas pressure to 60 kPa.

8.
Phys Rev Lett ; 93(26 Pt 1): 265002, 2004 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-15697985

RESUMEN

Multi-MeV electron generation by ultraintense laser pulses plays a major role in fast ignition laser fusion and related high energy density science. This Letter discloses a unique feature of relativistic electron motion and self-induced electromagnetic fields which depend upon laser incident angle and intensity. When the incident angle is larger than the critical value (theta> or =thetacr), despite an MeV electron being injected obliquely into the target, the high energy electron is decoupled from the bulk of the plasma and transported along the surface by the structured electron motion guided by the surface quasistatic electromagnetic field. The surface electromagnetic field and fast-electron density and current profiles are sustained as a quasisteady state by the intense laser irradiation. The analytical structures of the field and electron density agree reasonably well with 2D particle in cell simulation results.

9.
J Biosci Bioeng ; 97(3): 216-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-16233618

RESUMEN

To identify chemicals with endocrine-disrupting activity easily, we developed a new bioassay system, consisting of bioassay using genetically modified yeast expressing human estrogen receptor and high performance liquid chromatography (HPLC), in which advantages of instrumental analysis and bioassay are combined. The peaks in the mixture of these estrogen-like compounds analyzed using an HPLC bioassay were similar to those obtained by analysis using an HPLC-UV detector. Underground water and sea sediment were analyzed by an HPLC bioassay, and detected a few estrogen-like compounds, respectively. Estrogen-like compounds and yeast-growth inhibitors can be separated by HPLC-bioassay.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(2 Pt 2): 026401, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14525114

RESUMEN

A simple direct acceleration model is proposed, taking into account the stochastic phase disturbance of the coherent driving laser fields. A relativistic single particle simulation shows that plasma electrons are efficiently accelerated far above the ponderomotive energy. The energy and momentum distributions of the accelerated electrons are derived to examine the effects of the self-generated magnetic field on the characteristics of the electron beams. In addition to the beam collimation effect, the magnetic field is found to further enhance the electron acceleration, resulting in the generation of ultrahigh energy electrons.

11.
In. Hamada, Masanori, ed; O'Rourke, T. D., ed. Proceedings from the fourth Japan-U.S. Workshop on Earthquake Resistant Design of Lifeline Facilities and Countermeasures for Soil Liquefaction. New York, U.S. National Center for Earthquake Engineering Research (NCEER), Aug. 12 1992. p.639-53, ilus, tab. (Technical Report NCEER, 92-0019, 92-0019).
Monografía en En | Desastres | ID: des-7950

RESUMEN

THis paper discusses the results of several fundamental shaking table tests. The sandy model ground, which is compacted in the center and remains in the horizontal direction for design, it is significant to do such fundamental tests and to understand the behavior near the boundary.(AU)


Asunto(s)
Terremotos , Mecánica de Suelos , Suelos Arenosos , Investigación , 28574
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