Laser-Driven Proton-Only Acceleration in a Multicomponent Near-Critical-Density Plasma.

An experimental investigation of collisionless shock ion acceleration is presented using a multicomponent plasma and a high-intensity picosecond duration laser pulse. Protons are the only accelerated ions when a near-critical-density plasma is driven by a laser with a modest normalized vector potential. The results of particle-in-cell simulations imply that collisionless shock may accelerate protons alone selectively, which can be an important tool for understanding the physics of inaccessible collisionless shocks in space and astrophysical plasma.

Transition of average drug-to-antibody ratio of trastuzumab deruxtecan in systemic circulation in monkeys using a hybrid affinity capture liquid chromatography-tandem mass spectrometry.

Trastuzumab deruxtecan (T-DXd, DS-8201a) is an antibody-drug conjugate, comprising an anti-HER2 antibody at a drug-to-antibody ratio of 7-8 with the topoisomerase I inhibitor DXd. In this study, the concentrations of antibody-conjugated DXd and total antibody were determined and observed to decrease over time following intravenous administration of T-DXd to monkeys. The drug-to-antibody ratio of T-DXd also decreased in a time-dependent manner, which reached approximately 2.

Luminous, relativistic, directional electron bunches from an intense laser driven grating plasma.

Bright, energetic, and directional electron bunches are generated through efficient energy transfer of relativistic intense (~ 10 W/cm), 30 femtosecond, 800 nm high contrast laser pulses to grating targets (500 lines/mm and 1000 lines/mm), under surface plasmon resonance (SPR) conditions. Bi-directional relativistic electron bunches (at 40° and 150°) are observed exiting from the 500 lines/mm grating target at the SPR conditions. The surface plasmon excited grating target enhances the electron flux and temperature by factor of 6.

Predictive capability of material screening by fast neutron activation analysis using laser-driven neutron sources.

Bright, short-pulsed neutron beams from laser-driven neutron sources (LANSs) provide a new perspective on material screening via fast neutron activation analysis (FNAA). FNAA is a nondestructive technique for determining material elemental composition based on nuclear excitation by fast neutron bombardment and subsequent spectral analysis of prompt γ-rays emitted by the active nuclei. Our recent experiments and simulations have shown that activation analysis can be used in practice with modest neutron fluences on the order of 10 n/cm, which is available with current laser technology.

Robustness of large-area suspended graphene under interaction with intense laser.

Graphene is known as an atomically thin, transparent, highly electrically and thermally conductive, light-weight, and the strongest 2D material. We investigate disruptive application of graphene as a target of laser-driven ion acceleration. We develop large-area suspended graphene (LSG) and by transferring graphene layer by layer we control the thickness with precision down to a single atomic layer.

Comparison of SAR distribution of hip and knee implantable devices in 1.5T conventional cylindrical-bore and 1.2T open-bore vertical MRI systems.

Purpose: There is increasing use of open-bore vertical MR systems that consist of two planar RF coils. A recent study showed that the RF-induced heating of a neuromodulation device was much lower in the open-bore system at the brain and the chest imaging landmarks. This study focused on the hip and knee implants and compared the specific absorption rate (SAR) distribution in human models in a 1.

Energetic α-particle sources produced through proton-boron reactions by high-energy high-intensity laser beams.

In an experiment performed with a high-intensity and high-energy laser system, α-particle production in proton-boron reaction by using a laser-driven proton beam was measured. α particles were observed from the front and also from the rear side, even after a 2-mm-thick boron target. The data obtained in this experiment have been analyzed using a sequence of numerical simulations.

Direct observation of imploded core heating via fast electrons with super-penetration scheme.

Fast ignition (FI) is a promising approach for high-energy-gain inertial confinement fusion in the laboratory. To achieve ignition, the energy of a short-pulse laser is required to be delivered efficiently to the pre-compressed fuel core via a high-energy electron beam. Therefore, understanding the transport and energy deposition of this electron beam inside the pre-compressed core is the key for FI.

RF heating of deep brain stimulation implants in open-bore vertical MRI systems: A simulation study with realistic device configurations.

Purpose: Patients with deep brain stimulation (DBS) implants benefit highly from MRI, however, access to MRI is restricted for these patients because of safety hazards associated with RF heating of the implant. To date, all MRI studies on RF heating of medical implants have been performed in horizontal closed-bore systems. Vertical MRI scanners have a fundamentally different distribution of electric and magnetic fields and are now available at 1.

A ten-inch manipulator (TIM) based fast-electron spectrometer with multiple viewing angles (OU-ESM).

The measurement of angularly resolved energy distributions of mega-electron-volt electrons is important for gaining a better understanding of the interaction of ultra-intense laser pulses with plasma, especially for fast-ignition laser-fusion research. It is also crucial when evaluating the production of suprathermal (several 10-keV) electrons through laser-plasma instabilities in conventional hot-spot-ignition and shock-ignition research. For these purposes, we developed a 10-in.

An experimental platform using high-power, high-intensity optical lasers with the hard X-ray free-electron laser at SACLA.

An experimental platform using X-ray free-electron laser (XFEL) pulses with high-intensity optical laser pulses is open for early users' experiments at the SACLA XFEL facility after completion of the commissioning. The combination of the hard XFEL and the high-intensity laser provides capabilities to open new frontiers of laser-based high-energy-density science. During the commissioning phase, characterization of the XFEL and the laser at the platform has been carried out for the combinative utilization as well as the development of instruments and basic diagnostics for user experiments.

Acetylcholine spasm provocation test by trans-radial artery and brachial vein approach.

Background: Temporary pace maker is necessary because of transient block or bradycardia during the intracoronary acetylcholine spasm provocation tests based on the Japanese Circulation Society guidelines.

Objectives: We examined the feasibility and safety of the acetylcholine spasm provocation test via the radial artery and brachial vein approach.

Methods: We tried to perform the acetylcholine spasm provocation tests in 252 patients via the radial artery and brachial vein approach procedures during 5 years.

Differential incidence and morphology of provoked spasm between intracoronary acetylcholine and ergonovine testing: recommendation of supplementary use.

When cardiologists diagnose patients with coronary spastic angina, Japanese Circulation Society (JCS) guidelines recommend the intracoronary injection of acetylcholine (ACh) and ergonovine (ER) as class I. However, the pharmacological difference between ACh and ER is controversial in the clinic. We performed both ACh and ER tests in the same 528 patients during 26 years.

Catheter-induced Spasm in the Proximal Right Coronary Artery.

Objectives The clinical characteristics in patients with catheter-induced spasm in the proximal right coronary artery (RCA) are controversial. We performed a clinical analysis of catheter-induced spasm in the RCA. Methods We retrospectively analyzed 5,296 consecutive patients who underwent diagnostic or follow-up angiography during a 26-year period.

Cardiogenic Shock due to Pulseless Electrical Activity Arrest Associated with Severe Coronary Artery Spasm.

A 75-year-old man was admitted to our hospital for follow-up coronary angiography. Just after starting coronary angiography, his electrocardiogram showed ST-segment elevation in the V1-6, I, II, and aVF leads, and he fell into catastrophic cardiogenic shock. His left coronary arteriogram showed proximal total obstruction in the left anterior descending artery and proximal subtotal occlusion in the left circumflex artery.

Channel optimization of high-intensity laser beams in millimeter-scale plasmas.

Channeling experiments were performed at the OMEGA EP facility using relativistic intensity (>10^{18}W/cm^{2}) kilojoule laser pulses through large density scale length (∼390-570 μm) laser-produced plasmas, demonstrating the effects of the pulse's focal location and intensity as well as the plasma's temperature on the resulting channel formation. The results show deeper channeling when focused into hot plasmas and at lower densities, as expected. However, contrary to previous large-scale particle-in-cell studies, the results also indicate deeper penetration by short (10 ps), intense pulses compared to their longer-duration equivalents.

B-control receive array coil (B-RAC) for reducing B inhomogeneity in abdominal imaging at 3T-MRI.

B inhomogeneity in the human body increases as the nuclear magnetic resonance (NMR) frequency increases. Various methods have thus been developed to reduce B inhomogeneity, such as a dielectric pad, a coupling coil, parallel transmit, and radio-frequency (RF) shimming. However, B inhomogeneity still remains in some cases of abdominal imaging.

Approximately half of patients with coronary spastic angina had pathologic exercise tests.

Objectives: We examined the clinical usefulness of treadmill exercise tests (TETs) in diagnosing coronary spastic angina (CSA).

Methods: We performed the TETs and 24-h Holter monitoring in 300 CSA patients consisting of 152 patients with rest angina, 77 patients with effort angina, and 71 patients with rest and effort angina. Organic stenosis (>75%) was observed in 44 patients.

Density and temperature characterization of long-scale length, near-critical density controlled plasma produced from ultra-low density plastic foam.

The ability to produce long-scale length (i.e. millimeter scale-length), homogeneous plasmas is of interest in studying a wide range of fundamental plasma processes.

Slowdown mechanisms of ultraintense laser propagation in critical density plasma.

We use one- and two-dimensional particle-in-cell simulations to demonstrate that the propagation of an ultraintense laser (I=10(19)W/cm(2)) in critical density plasma can be interfered with by a high density plasma wall region generated at the propagation front. When the electron flow speed of the wall region exceeds a certain relativistic threshold, the region behaves as an overdense plasma due to a decrease of the effective critical density. The region forms then very small overdense plasma islands.

Channeling of multikilojoule high-intensity laser beams in an inhomogeneous plasma.

Channeling experiments were performed that demonstrate the transport of high-intensity (>10(18)W/cm(2)), multikilojoule laser light through a millimeter-sized, inhomogeneous (∼300-μm density scale length) laser-produced plasma up to overcritical density, which is an important step forward for the fast-ignition concept. The background plasma density and the density depression inside the channel were characterized with a novel optical probe system. The channel progression velocity was measured, which agrees well with theoretical predictions based on large scale particle-in-cell simulations, confirming scaling laws for the required channeling laser energy and laser pulse duration, which are important parameters for future integrated fast-ignition channeling experiments.

Sequential spasm provocation tests might overcome a limitation of the standard spasm provocation tests.

Objective: We examined the clinical usefulness of sequential spasm provocation tests as follows: first, acetylcholine (ACh) test, second, ergonovine (ER) test, and finally, the ACh test following the ER test.

Patients And Methods: We performed the ACh and ER tests in 461 patients (294 men, 64.4±11.

Silent coronary spastic angina: A report of a case.

A 54-year-old man was admitted to our hospital due to abnormal electrocardiogram (ECG) changes. He had experienced no chest pain or chest discomfort during daily life until then. Ischemic ECG change was obtained by the treadmill exercise test but he complained of no chest pain or chest oppression.