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We developed an electron beam detector installed between the superconducting solenoids in ExtentedEBIS. The detector is two-sided. Each side has 4 quadrant plates with an aperture slightly larger than the electron beam radius. The gun-side is for alignment of primary electron beam. The collector side detector is to measure the electrons back-streaming from the collector or the downstream electrodes to the cathode. It is important to understand how the back-streaming electrons behave and how to control it. The detector was designed with considerations of heat load. The influence on the electric potential distribution was investigated. A detector test showed that the back-streaming electrons were affected by the external electromagnetic fields and the space charge of the primary electron beam. It was proved that the behaviour of the electrons can be observed by this detector.

Context: Small intracranial aneurysms (IAs) are considered to have a low risk of rupture; however, in clinical practice, we often encounter patients with subarachnoid hemorrhage (SAH) due to rupture of small IAs. Aims: This study aims to clarify the clinical and morphological characteristics of ruptured small IA, focusing on posterior communicating artery (PCoA) aneurysms as a prone site. Settings and Design: We retrospectively reviewed 102 consecutive patients with SAH due to ruptured PCoA aneurysm who underwent microsurgical or endovascular aneurysm repair between April 2013 and March 2018. Subjects and Methods: All PCoA aneurysms were diagnosed using three-dimensional rotation angiography or three-dimensional computed tomography angiography. Information regarding the following clinical characteristics was collected: age, sex, past medical history, current smoking, antithrombotic therapy, multiplicity, hydrocephalus, intracerebral hemorrhage, intraventricular hemorrhage, and World Federation of Neurosurgical Societies (WFNS) Grade on admission. Statistical Analysis Used: We analyzed factors of ruptured small IA, focusing on PCoA aneurysms using univariate and multivariate regression analyses. Results: Univariate and multivariate analyses revealed that low aspect ratio (AR) (odds ratio [OR] = 0.33, P = 0.01) and nonfetal type of PCoA (OR = 0.31, P = 0.02) might be independent characteristics of ruptured small PCoA aneurysms. However, age, sex, past medical history, WFNS grade, and treatment outcome were not different between the small and nonsmall PCoA aneurysms. The aneurysm size was not associated to the selection of treatment, proportion of complications, and treatment outcome. Conclusions: In cases of ruptured PCoA aneurysms, low AR and nonfetal type of PCoA might be associated with rupture of small aneurysms.

© Owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). The capability of accelerating a high-intensity polarized 3He ion beam would provide an effective polarized neutron beam for new high-energy QCD studies of nucleon structure. This development is essential for the future Electron Ion Collider, which could use a polarized 3He ion beam to probe the spin structure of the neutron. The proposed polarized 3He ion source is based on the Electron Beam Ion Source (EBIS) currently in operation at Brookhaven National Laboratory. 3He gas would be polarized within the 5 T field of the EBIS solenoid via Metastability Exchange Optical Pumping (MEOP) and then pulsed into the EBIS vacuum and drift tube system where the 3He will be ionized by the 10 Amp electron beam. The goal of the polarized 3He ion source is to achieve 2.5 × 1011 3He++/pulse at 70% polarization. An upgrade of the EBIS is currently underway. An absolute polarimeter and spin-rotator is being developed to measure the 3He ion polarization at 6 MeV after initial acceleration out of the EBIS. The source is being developed through collaboration between BNL and MIT.

Machine learning techniques have realized some principal cognitive functionalities such as nonlinear generalization and causal model construction, as far as huge amount of data are available. A next frontier for cognitive modelling would be the ability of humans to transfer past knowledge to novel, ongoing experience, making analogies from the known to the unknown. Novel metaphor comprehension may be considered as an example of such transfer learning and analogical reasoning that can be empirically tested in a relatively straightforward way. Based on some concepts inherent in category theory, we implement a model of metaphor comprehension called the theory of indeterminate natural transformation (TINT), and test its descriptive validity of humans' metaphor comprehension. We simulate metaphor comprehension with two models: one being structure-ignoring, and the other being structure-respecting. The former is a sub-TINT model, while the latter is the minimal-TINT model. As the required input to the TINT models, we gathered the association data from human participants to construct the ``latent category'' for TINT, which is a complete weighted directed graph. To test the validity of metaphor comprehension by the TINT models, we conducted an experiment that examines how humans comprehend a metaphor. While the sub-TINT does not show any significant correlation, the minimal-TINT shows significant correlations with the human data. It suggests that we can capture metaphor comprehension processes in a quite bottom-up manner realized by TINT.

Background: Tortuous/abnormal vertebral arteries (VAs) sometimes cause neurovascular compression syndromes (NVCs), such as trigeminal neuralgia, hemifacial spasm, and, rarely, myelopathy/radiculopathy. Abnormalities/tortuosity of the VA at the level of the atlas and axis are of particular note; these may be characterized by a persistent first intersegmental artery (PFIA) and C2 segmental type of VA. Herein, we report a 72-year-old male who presented with cervical myelopathy/radiculopathy due to bilateral tortuosity of the PFIA resulting in spinal cord compression at the craniocervical junction. Case Description: A 72-year-old male presented with cervical pain when turning his neck and progressive gait disturbance. The neurological examination demonstrated a moderate myeloradicular syndrome (Nurick Grade III). The magnetic resonance revealed compression of the medulla and spinal cord due to tortuosity of both dorsal VA at the C1 vertebral level. The three-dimensional computed tomography angiogram confirmed bilateral PFIA running medially. In addition, the left side of VA forms fenestration. Surgery through a C1 laminectomy and midline small suboccipital craniectomy, both VAs were transposed and tethered to the ipsilateral dura utilizing Aron Alpha and vinyl prostheses. In addition, a large vinyl prosthesis was inserted between both VAs to protect them from contacting the spinal cord. Following this decompressive procedure, the patient’s symptoms fully resolved, and he remains asymptomatic 10 years later exhibiting no recurrent vascular pathology. Conclusion: Microvascular decompression of anomalous VAs contributing to cord compression at the C1 level was safe and effective in a 72-year-old male.

A laser ion source coupled with a radio frequency quadrupole linac accelerator is being proposed as a suitable system for the production of a low energy, high-current stable lithium beam. In order to maximize the lithium yield, plasmas generated by laser ablation of different materials based on lithium (Li, LiOH, and LiNbO3) have been characterized by using a Faraday cup and an electrostatic ion analyzer in the time of flight configuration. A wide range of laser power density has been investigated (109–1012 W/cm2) using two Nd:YAG lasers operating at different wavelengths (1064 nm and 532 nm), pulse durations (6 ns and 17 ns), and maximum energies (1400 mJ and 210 mJ). This paper outlines the pros and cons of the investigated materials by studying how the ion energy, yields, and charge state distributions are modified when the laser power density is changed. Considerable attention has been paid to the higher charge states of oxygen, which may occur with the same mass-to-charge ratio of Li3+. The analysis has evidenced that LiNbO3 represents a valid target since it allows minimizing the O6+/7Li3+ ratio down to 2.5% by using a laser power density of 1.8 × 1010 W/cm2. For such a condition, a Li3+ current of 1.4 mA/cm2 has been measured.

In recent years, the primary ion source for the Brookhaven National Laboratory has been the laser ion source, which provides many types of ions within a short switching time of several seconds. The task is difficult for other ion sources. In the previous work, we tested metallic lithium as a target material of the laser irradiation. Although an intense lithium beam was demonstrated, some operational difficulties were observed due to its reactiveness to oxygen. For accelerator applications, a more robust and reliable target material has been demanded. For this purpose, we tested lithium niobate, LiNbO3. Our study investigated the optimization of power density to produce low charge state lithium ions. We struck LiNbO3 with the laser and found lithium ion quantities for five different power densities. Based on the data obtained, we can conclude that the most efficient production of Li1+ occurs when the laser power density is 5 × 108 W/cm2.

Laser power density per pulse, which is commonly expressed with the unit of “W/cm2,” is an important parameter to characterize ablation plasma. To match a design charge state of heavy ion beam induced by a laser ion source, a laser power density must be carefully chosen. Above around 108 W/cm2 of laser power density, laser ablation plasma is emitted from the surface of solid material. Then, up to 109 W/cm2, the most abundant charge state is 1+. Because the ionization energy increases with higher charge states, increasing the laser intensity leads to the charge state distribution shifting higher. Increasing the density to increase charge states also results in lower time of flight due to higher velocities. The maximum laser power density is obtained by the smallest available laser spot size on the target material which is determined by the quality of the laser beam. For many accelerator applications, higher charge state beams are preferred. In particular cases, singly charge ion beams are demanded. Therefore, production of intermediate charge state beams has not been investigated well. In this study, we selected Ta4+ as an example demanded beam and tried to clarify how the transition of charge state distribution depends on laser power density. Conclusively, the possible specification of a laser ion source for Ta4+ delivery was elucidated.

We investigated the surface dilational viscoelasticities of aqueous solutions of dihexanoyl-phosphastidylcholine (DC6PC) and dioctanoyl-phosphastidylcholine (DC8PC), dodecyltrimethylammonium bromide (DTABr) and DTABr and sodium bromide (NaBr), dodecyltrimethylammonium tetrafluoroborate (DTABF4) and bisdodecyltrimethylammonium sulfate (DTA2SO4), and nonionic surfactants with oxyethylene units (C10E5). We measured surface quasi-elastic light scattering (SQELS) spectra and analyzed the solutions by both surface rheological and phenomenological fitting approaches. For the DC6PC-DC8PC mixture, the electrocapillary wave (ECW) method was also applied. The molecular interactions between DC8PC and DC6PC in the adsorbed film clearly influenced the relaxation process on the order of several milliseconds (ECW). However, the effects were less influential on the order of several hundreds of microseconds (SQELS). The characteristic frequencies for relaxation owing to the staggered structure formation likely occurred in the range from 150 to 300 Hz. The dilational elasticity at 250–400 kHz of DTABr suggested that the main relaxation process influencing the dilational properties was neither diffusion of surfactants from the bulk phase to the subsurface nor an adsorption-desorption of surfactant ions between the adsorbed layer and subsurface. However, the diffusion of counterions between the Stern and diffuse layers occurred on a time scale of several microseconds. Studies of C10E5 suggested that the relaxation process captured by the SQELS studies was neither related to surfactant diffusion nor surfactant reorientation, but rather was likely to be a relaxation process where distortion of the hydration sphere and/or hydration-dehydration to/from the hydration sphere was caused by diffusion of water molecules.

The aim of this study was to clarify the factors associated with requiring subacute surgery in patients with acute subdural hematoma (ASDH) treated conservatively at admission. Among the patients with ASDH admitted to our hospital from 2007 to 2018, we retrospectively reviewed data for 200 patients initially treated conservatively. We compared patients’ characteristics, medical history, radiological findings, and clinical outcomes and differences between patients undergoing subacute surgery or no surgery. Of the 200 patients treated conservatively, 17 (8.5%) patients underwent subacute surgery due to deterioration of their clinical and/or computed tomography (CT) findings, while 183 (91.5%) patients did not undergo subacute surgery. There were significant differences in the presence of focal neurological deficits, modified Rankin Scale scores, degree of midline shift, hematoma thickness, hematoma volume, cella media index, Sylvian fissure ratio, and hematoma density between the two groups. Large hematoma, brain atrophy, and hematoma density may be useful predictors for the need for subacute surgery in patients with ASDH treated conservatively at admission. Intensive investigation of clinical findings or CT images is warranted in patients with adverse prognostic factors, even if their initial symptoms are mild.

A laser ion source (LIS) is a promising candidate as an ion source for heavy-ion inertial fusion (HIF), where a pulsed ultra-intense and low-charged heavy ion beam is required. It is a key development for a LIS to transport laser-produced plasma with a magnetic field to achieve a high-current beam. The effect of a tapered magnetic field on laser-produced plasma is demonstrated by comparing the results with a straight solenoid magnet. The magnetic field of interest is a wider aperture on a target side and narrower aperture on an extraction side. Based on the experimentally obtained results, the performance of a scaled LIS for HIF was estimated.

This report describes clinicopathological findings, including genetic data of STAT6, in a solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) of the central nervous system in an 83-year-old woman with a bulge in the left forehead. She noticed it about 5 months before, and it had grown rapidly for the past 1 month. Neuroradiological studies disclosed a well-demarcated tumor that accompanied the destruction of the skull. The excised tumor showed a prominent papillary structure, where atypical cells were compactly arranged along the fibrovascular core ('pseudopapillary'). There was rich vasculature, some of which resembled 'staghorn' vessels. Mitotic figures were occasionally found. Whorls, psammoma bodies, or intra-nuclear pseudoinclusions were not identified. By immunohistochemistry, CD34 was strongly positive in the tumor cells, and STAT6 was localized in their nuclei. By reverse transcription-polymerase chain reaction (RT-PCR), an NAB2-STAT6 fusion gene, NAB2 exon6-STAT6 exon17, was detected, establishing a definite diagnosis of SFT/HPC. 'Papillary' SFT/HPC needs to be recognized as a possible morphological variant of SFT/HPC, and should be borne in mind in its diagnostic practice.

A solenoidal magnetic field has been used to enhance the ion flux of a laser ion source. However, the dependence of the increase in ion current on the charge-state has not been clarified. In this study, to control the purity of the charge-state in the laser ion source, we investigated the effect of a solenoidal magnetic field on the charge-state distribution of ions in laser ion sources with a solenoid. The results indicate that the flux of ions with a heavier and/or lower charge-state can be increased using higher magnetic flux densities, and that each charged ion has an optimal solenoidal magnetic flux density that maximizes its flux. These results imply that it is possible to increase the purity of the desired charge-state ions by selecting a suitable solenoidal magnetic flux density.

Using a solenoid with a laser ion source can suppress divergence of the expanding plasma; however, it has been found that the plasma becomes unstable in a certain magnetic field region. In the previous research, instability of the plasma after the solenoid was found. In this study, we investigated how the plasma instability changes inside the solenoid. A Faraday cup was placed in the solenoid, and the unstable magnetic field range was investigated. This experiment was conducted while changing the Faraday cup position from the inlet to the outlet of the solenoid. By increasing the magnetic field strength, the Faraday cup position indicating a condition triggering instability moved toward upstream in the solenoid. In addition, the instability is gradually mitigated by transporting the laser ablation plasma through the rest of the solenoid. The detailed good working range of the solenoid for the Au1+ beam was also shown.

We are developing a laser ion source to provide a high brightness multi-charged heavy ion beam as a part of the heavy ion beam probe system, which will be used to diagnose plasma potential in the Ring Trap 1 device at the University of Tokyo. As a probe beam, Nb2+ was selected, and a detailed laser irradiation condition was explored. It was found that the laser power density of 1.2 × 109 W/cm2 gives the maximum particle number of Nb2+ per laser energy from a niobium foil target. Essential ablation plasma parameters to design the laser ion source were also obtained. The expected beam current was more than 12 mA/cm2, with a pulse width of 3.1 µs at 200 mm away from the target.

The upgrade of the EBIS, called ExtendedEBIS, is now in progress in Brookhaven National Laboratory. Two 5T-superconducting solenoids have been placed in series with 200 mm distance from each other for higher trap capacity and production of polarized 3He ions. Since the two superconducting solenoids are used, the field error is expected to be larger. In this research, the field error is estimated based on simulation. It was found that the magnetic field line can be 17 mm off from the center axis at the entrance of the collector, and this offset can be adjusted by three types of correction coils. Additionally, mismatch of the spin direction of polarized 3He due to the misalignment was estimated to be small.

To investigate the chiral magnetic effect, 96Zr and 96Ru beams were accelerated at the relativistic heavy ion collider (RHIC) during Run-18 at Brookhaven National Laboratory. The 96Zr beam was provided from the electron beam ion source (EBIS) injector, which consists of a laser ion source, an EBIS high charge state ion breeder, a 300 keV/u radio frequency quadrupole, and a 2 MeV/u interdigital H type drift tube linear accelerator (IH-DTL). The natural abundance of 96Zr is only 2.8% with about 50% of 90Zr. To obtain a sufficient beam current, Zr material enriched to about 60% of 96Zr was used. The only available form of the enriched material was zirconium oxide (ZrO2) powder, which was not well suited for a laser ion source target. We studied and established a sintering technique of the ZrO2 powder to make a solid sample which could be installed into the laser ion source. The singly charged Zr was produced in a laser ablation plasma, extracted, and delivered to the EBIS to be ionized further to 96Zr16+. We optimized the laser irradiation condition, the EBIS confinement time, and transport through the RF linacs to maximize the performance of the injector. The total number of shots provided from the laser ion source for injection into the EBIS was 489 910. The EBIS facility provided a 192 MeV stable beam of 96Zr16+ ions to the booster ring of alternating gradient synchrotron (AGS) for further acceleration and stripping in the AGS/RHIC complex, allowing for successful data acquisition at the Solenoidal Tracker at the RHIC.

Background & Objectives: The mechanism of microcirculatory disturbance following subarachnoid hemorrhage (SAH) remains to be elucidated. In this study, we investigated the correlation between the cerebral microcirculatory change and the time-dependent alteration of major arterial vasoconstriction after SAH using rabbit SAH model. Methods: CT angiography and perfusion were repeated at 0, 1, 6, 24, 48 hours after first hemorrhage for acute changes observation group (n=8), and on days 0, 3, 5, 7 for chronic changes observation group (n=8) using multi-detector raw CT. Regional cerebral blood flow (rCBF), cerebral blood volume (CBV), mean transit time (MTT) and basilar artery (BA) diameter were calculated at each time point. Results: In acute group, immediately after hemorrhage, BA narrowed, both CBV and rCBF were decreased and MTT was increased, transiently. After 6 hours, BA narrowed again and both CBV and rCBF were increased progressively. MTT restored over 24 hours. In chronic group, BA narrowing reached a peak on day 5 and restored after day 7. Both CBV and rCBF were persistently decreased after day 3, while MTT was increased after day 5. In both groups, no significant changes were observed in CBV, rCBF and MTT between in BA territory and other territory. Conclusions: Delayed cerebral ischemia may be caused by the microcirculatory disturbance which is regulated by independent mechanisms from major arterial vasospasm both in the acute and chronic phase after SAH in rabbit model.

Background: Cerebral vasospasm (CVS) is a major determinant of prognosis in patients with subarachnoid hemorrhage (SAH). Alteration in the vascular phenotype contributes to development of CVS. However, little is known about the role of microRNAs (miRNAs) in the phenotypic alteration after SAH. We investigated the expression profile of miRNAs and the chronological changes in the expression of microRNA-15a (miR-15a) and Kruppel-like factor 4 (KLF4), a potent regulator of vascular phenotype modulation that modulates the expression of miR-15a, in the plasma and cerebrospinal fluid (CSF) of SAH patients. Methods: Peripheral blood and CSF samples were collected from eight aneurysmal SAH patients treated with endovascular obliteration. Samples obtained from three patients without SAH were used as controls in the analysis. Exosomal miRNAs were isolated and subjected to microarray analysis with the 3D-gene miRNA microarray kit. The time course of the expression of miR-15a and KLF4 was analyzed using quantitative real-time PCR. Results: Microarray analysis demonstrated that 12 miRNAs including miR-15a were up- or down-regulated both in the CSF and plasma after SAH within three days. Quantitative real-time PCR revealed that miR-15a expression was significantly increased in both the CSF and plasma, with a peak around 3 to 5 days after SAH, whereas the expression of KLF4 was significantly decreased around 1 to 3 days after SAH and remained lower than in controls. Conclusion: Our results suggest that an early and persistent decrease in KLF4 followed by an increase in miR-15a may contribute to the altered vascular phenotype, resulting in development of CVS.

To provide 96Zr beam from the laser ion source, we are investigating the characteristics of sintered Zr oxide target. Zirconium has several isotopes and 96Zr occupies only about 2 - 3%. Therefore, to provide intense 96Zr beam, the laser target material needs to be enriched. Enriched 96Zr may be easily obtained as oxide powder form in the market, we are testing natural abundance Zr oxide powder instead of expensive enriched material. As a method of creating an oxide laser target, sintering is being tried. In the laser plasma from the sintered oxide target, impurities including oxygen ions were observed. We also measured target material consumptions assuming realistic laser irradiation conditions those may be employed in the RHIC (Relativistic Heavy Ion Collider) experiment in the next year.

We have investigated the mechanism of a slow tail of low charge state ions in laser ablation plasma produced for highly charged ion generation such as C6+. In the previous experiments with different thickness of graphite sheets (3000 µm, 254 µm, 70 µm, and 25 µm), the low charge state tail was reduced only with the 25 µm sheet. To precisely investigate the phenomena further, we carefully studied the difference of charge states in laser produced plasma from 3000 µm, 25 µm and 17 µm graphite foils. The very similar reduction of the second peak for both 25 and 17 µm was observed. We confirmed that the reduction of total ion current measured by a faraday cup at the falling edge was contributed by C4+ and C5+.

Laser-generated non-equilibrium plasmas were analyzed at Brookhaven National Laboratory (NY, USA) and MIFT Messina University (Italy). Two laser intensities of 1012 W/cm2 and 109 W/cm2, have been employed to irradiate Al and Al with Au coating targets in high vacuum conditions. Ion energy distributions were obtained using electrostatic analyzers coupled with ion collectors. Time of flight measurements were performed by changing the laser irradiation conditions. The study was carried out to provide optimum keV ions injection into post acceleration systems. Possible applications will be presented.

To control the plasma flux of a laser ion source for a desired beam profile, we investigated the influence of a quasi-static magnetic field generated by a solenoidal coil on the tail of an Fe ablation plasma. We observed that the magnetic field converged the outer plasma and almost did not affect the inner plasma when the plasma drifted through the field region. The convergence points of the outer plasma depended on the longitudinal velocity. The results indicate that diamagnetic current was induced in the outer plasma, and therefore, the outer plasma received the converging force and the magnetic field in the inner region was excluded by the plasma intrusion. The results also mean that we have to consider the magnetic effect on the transverse distribution of plasma flux to minimize the emittance growth and obtain desirable beam optics.

To realize a heavy-ion inertial fusion (HIF) driver, we have studied a possibility of laser ion source (LIS). A LIS can provide high-current high-brightness heavy-ion beams; however, it was difficult to manipulate the beam parameters. To overcome the issue, we employed a pulsed solenoid in the plasma drift section and investigated the effect of the solenoid field on singly charged iron beams. The rapid ramping magnetic field could enhance limited time slice of the current and simultaneously the beam emittance changed accordingly. This approach may also be useful to realize an ion source for HIF power plant.

We investigated the interaction of a laser ablation plasma with a longitudinal magnetic field aiming to create a directionally moving plasma for high-flux and low-emittance ion injectors. To study the plasma dynamics, time-of-flight measurements and energy analysis of the plasma ion flux were made as functions of the laser intensity and the magnetic field. Moderate magnetic field ( ∼ 0.2 T ) directed the fast and highly charged ions in the target normal. In addition, a slow peak appeared and increased with increasing the magnetic field. These results indicated that directional electric field is formed and recombination increases by the application of longitudinal magnetic field.

Background Vascular anomalies accompanied with the diploic veins are rare. Among them, sinus pericranii, which is characterized by abnormal connections between intra- and extracranial venous systems, is relatively common. Besides sinus pericranii, a few cases of subepicranial varix with connections to diploic veins have been reported, but these varices had no connections to intracranial venous sinuses. Herein, we present a rare case of an expanding venous sac in the diploe which communicated with the intracranial sinus but not with the extracranial venous systems. Case presentation An adult woman presented to us with a minor transient headache. Although no abnormal appearances were found on her scalp, imaging studies showed a club-shaped venous sac in the left parietal diploe that communicated with the superior sagittal sinus and diploic veins on the medial and lateral sides, respectively. It was revealed that the lesion had expanded as compared with a previous computed tomography image. Surgery was performed to intercept venous supply from the diploic veins, and the lesion was filled with thrombi. In a follow-up of 15 months, there was no recurrence of abnormal venous flow. Histological examination showed the endothelial lining in the membranous wall of the sac, which is typically observed in sinus pericranii. However, no communication with the pericranial veins of the scalp was identified on the imaging studies and intraoperative observation. Accordingly, it was diagnosed as another entity “intradiploic varix”. Conclusions The abnormal connection between the intracranial and the diploic venous systems via the large venous sac was surgically treated. It was pathologically similar to sinus pericranii, but anatomically considered to be another form of venous anomaly. In cases of expanding lesions, surgical treatment is recommended.

Calcium and lithium ion beams are required by NASA Space Radiation Laboratory at Brookhaven National Laboratory to simulate the effects of cosmic radiation. To identify the difficulties in providing such highly reactive materials as laser targets, both species were experimentally tested. Plate shaped lithium and calcium targets were fabricated to create ablation plasmas with a 6 ns 1064 nm neodymium-doped yttrium aluminum garnet laser. We found significant oxygen contamination in both the Ca and Li high charge state beams due to the rapid oxidation of the surfaces. A large spot size, low power density laser was used to create low charge state beams without scanning the targets. The low charge state Ca beam did not have any apparent oxygen contamination, showing the potential to clean the target entirely of oxide with a low power beam once in the chamber. The Li target was clearly still oxidizing in the chamber after each low power shot. To measure the rate of oxidation, we shot the low power laser at the target repeatedly at 10 s, 30 s, 60 s, and 120 s interval lengths, showing a linear relation between the interval time and the amount of oxygen in the beam.

Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is (96)Ru + (96)Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions.

We studied proton beam production from a laser ion source using hydrogen rich target materials. In general, gas based species are not suitable for laser ion sources since formation of a dense laser target is difficult. In order to achieve reliable operation, we tested hydride targets using a sub nanosecond Q-switched Nd-YAG laser, which may help suppress target material consumption. We detected enough yields of protons from a titanium hydride target without degradation of beam current during the experiment. The combination of a sub nanosecond laser and compressed hydride target may provide stable proton beam.

In the laser ion source (LIS) at the Brookhaven National Laboratory (BNL), a solenoid is used to guide the laser ablation plasma and modulate the extracted beam current. Many types of ion species are guided. In some cases, the plasma plume is injected into the solenoid away from the solenoidal axis. To investigate the effects of the solenoid on the beam extracted from the plasma that has different properties, the beam current was measured in the setup of the LIS at the BNL. The beam current of Li, Al, Si, Fe, and Au increased when the magnetic field was applied. For most of the species the peak current and the total charge within a single beam pulse increased around 10 times with a magnetic field less than 100 G. In addition, for some species the rate of increase of the peak currents became smaller when the magnetic flux densities were larger than certain values depending on the species. In this case, the current waveforms were distorted. At the same magnetic field value, the field was more effective on lighter species than on heavier ones. When plasma was injected offset from the axis of the solenoid, peak current and total charge became half of those without offset. The experimental data are useful for the operation of the LIS at the BNL.

A laser ablation plasma formation process was investigated by shooting another laser beam. The initial plasma was created by a mildly focused nanosecond laser beam and the probe laser, which has about ten times shorter pulse length with tightly focussed condition, was irradiated on it. By analysing high temperature plasma created by the probe laser, we could detect an interaction between the initial low temperature plasma and the probe laser. The interaction caused that the velocity of high temperature plasma generated by the sub-ns laser became smaller and the amount of the highly charged ions decreased. We found that the interaction does not occur during the irradiation of the first half of the ns laser. This fact indicates that the plasma is not produced during the first half of the ns laser.

Background Context Little is known on the natural course of ruptured spinal artery aneurysm, and a treatment strategy remains to be elucidated. Purpose This case report aims to describe a rare case of a posterior spinal artery aneurysm that showed progressive thrombosis following subarachnoid hemorrhage. Study Design This is a case report and literature review. Methods A 54-year-old man presented with subarachnoid hemorrhage due to posterior spinal artery aneurysm at the T10 level. The patient underwent surgery 19 days after onset. Results Most of the aneurysm appeared unenhanced on intraoperative indocyanine green video angiography, and total resection was performed. Histologic examination confirmed spontaneous thrombosis of the lesion. A review of the literature identified 19 cases of ruptured posterior spinal artery aneurysm. Thrombosed aneurysm and thrombosed parent artery were observed in 7 (44%) of the 16 cases treated with surgical or endovascular interventions. In the three cases treated conservatively, fatal rebleeding in the acute stage was noted in one case, whereas the lesion disappeared spontaneously in the chronic stage without rebleeding in two cases. Conclusions Ruptured spinal artery aneurysms are prone to spontaneous thrombosis. The healing process of the lesion was well documented in the present case. Repeated angiographic follow-up offers a feasible alternative in the management of this fairly rare aneurysm.

Factor B is a serine-protease zymogen in the horseshoe crab coagulation cascade, and it is the primary substrate for activated factor C, the LPS-responsive initiator of the cascade. Factor C is autocatalytically activated to α-factor C on LPS and is artificially converted to β-factor C, another activated form, by chymotrypsin. It is not known, however, whether LPS is required for the activation of factor B. Here we found that wild-type factor B expressed in HEK293S cells is activated by α-factor C, but not by β-factor C, in an LPS-dependent manner and that β-factor C loses the LPS binding activity of factor C through additional cleavage by chymotrypsin within the N-terminal LPS-binding region. Surface plasmon resonance and quartz crystal microbalance analyses revealed that wild-type factor B binds to LPS with high affinity comparable with that of factor C, demonstrating that factor B is the second LPS-binding zymogen in the cascade. An LPS-binding site of wild-type factor B was found in the N-terminal clip domain, and the activation rate of a clip domain deletion mutant was considerably slower than that of wild-type factor B. Moreover, in the presence of LPS, Triton X-100 inhibited the activation of wild-type factor B by α-factor C. We conclude that the clip domain of factor B has an important role in localizing factor B to the surface of Gram-negative bacteria or LPS released from bacteria to initiate effective proteolytic activation by α-factor C.

A high-pass-filtered (HPF) pulse injection technique is proposed to reduce spurs near the carrier signal due to injection locking. By using this technique, a multi-band quadrature clock generator consisting of a wide-frequency range injection-locked PLL and a frequency-selectable local buffer is demonstrated. The proposed clock generator was fabricated in a 65 nm CMOS. For a 100 MHz reference, the circuit can output 1.0, 2.0, and 4.0 GHz quadrature outputs with an eight-phase VCO and the buffer. It shows an 1 MHz-offset phase noise -105 dBc/Hz and a reference spur level of -50 dBc at 2.0 GHz, with enabling HPF pulse injection. The total power consumption is lower than 32 mW at 4 GHz.