4ff electron temperature driven ultrafast electron localization

Valence transitions in strongly correlated electron systems are caused by orbital hybridization and Coulomb interactions between localized and delocalized electrons. The transition can be triggered by changes in the electronic structure and is sensitive to temperature variations, applications of magnetic fields, and physical or chemical pressure. Launching the transition by photoelectric fields can directly excite the electronic states and thus provides an ideal platform to study the correlation among electrons on ultrafast timescales. The EuNi$_2$(Si$_{0.21}$Ge$_{0.79}$)$_2$ mixed-valence metal is an ideal material to investigate the valence transition of the Eu ions via the amplified orbital hybridization by the photoelectric field on sub-picosecond timescales. A direct view on the 4$f$ electron occupancy of the Eu ions is required to understand the microscopic origin of the transition. Here we probe the 4$f$ electron states of EuNi$_2$(Si$_{0.21}$Ge$_{0.79}$)$_2$ at the sub-ps timescale after photoexcitation by X-ray absorption spectroscopy across the Eu $M_5$-absorption edge. The observed spectral changes due to the excitation indicate a population change of total angular momentum multiplet states $J$ = 0, 1, 2, and 3 of Eu$^{3+}$, and the Eu$^{2+}$ $J$ = 7/2 multiplet state caused by an increase in 4$f$ electron temperature that results in a 4$f$ localization process. This electronic temperature increase combined with fluence-dependent screening accounts for the strongly non-linear effective valence change. The data allow us to extract a time-dependent determination of an effective temperature of the 4$f$ shell, which is also of great relevance in the understanding of metallic systems' properties, such as the ultrafast demagnetization of ferromagnetic rare-earth intermetallics and their all-optical magnetization switching.Comment: 19 pages, 9 figure

A Randomized Controlled Trial of Comprehensive Early Intervention Care in Patients with First-Episode Psychosis in Japan: 1.5-year Outcomes from the J-CAP Study

The first episode of psychosis represents a critical period wherein comprehensive early intervention in psychosis (EIP) may alter the course of illness. However, evidence from randomized controlled trials that have examined the impact of comprehensive EIP care on clinical and functional recovery assessed by independent blinded raters is limited. The objective of this study was to conduct a single-blinded multicenter trial comparing comprehensive EIP care and standard care in young patients with first-episode psychosis (FEP) in Japan (J-CAP Study). A total of 77 participants with FEP (aged 15–35 years) were randomized to receive standard care or specialized comprehensive EIP care and were followed up for 1.5 years (trial no.: UMIN000005092). Function (measured with the Global Assessment of Functioning) and clinical remission (defined by internationally standardized criteria proposed by the Remission in Schizophrenia Working Group) were evaluated by independent raters who were blinded to group assignment. Dropout rate and other secondary outcomes were also examined. The specialized EIP care group had a higher clinical remission rate (odds ratio, 6.3; 95% confidence interval, 1.0–37.9) and lower treatment dropout rate (odds ratio, 0.038; 95% confidence interval, 0.002–0.923) than the standard care group, even after adjusting for baseline characteristics. Functional improvement in the specialized EIP care group was slightly higher than that in the standard care group, but this difference was not statistically significant (p = 0.195). From the results, we conclude that comprehensive EIP care may provide advantages over standard care in patients with FEP

Effects of Moderate Hypothermia on Constitutive and Inducible Nitric Oxide Synthase Activities After Traumatic Brain Injury in the Rat

: We investigated the effects of therapeutic hypothermia (30°C) on alterations in constitutive (cNOS) and inducible (iNOS) nitric oxide synthase activities following traumatic brain injury (TBI). Male Sprague–Dawley rats were anesthetized with 0.5% halothane and underwent moderate (1.8–2.2 atm) parasagittal fluid‐percussion (F‐P) brain injury. In normothermic rats (37°C) the enzymatic activity of cNOS was significantly increased at 5 min within the injured cerebral cortex compared with contralateral values (286.5 ± 68.9% of contralateral value; mean ± SEM). This rise in nitric oxide synthase activity was significantly reduced with pretraumatic hypothermia (138.8 ± 17% of contralateral value; p < 0.05). At 3 and 7 days after normothermic TBI the enzymatic activity of cNOS was decreased significantly (30 ± 8.4 and 28.6 ± 20.9% of contralateral value, respectively; p < 0.05). However, immediate posttraumatic hypothermia (3 h at 30°C) preserved cNOS activity at 3 and 7 days (69.5 ± 23.3 and 78.6 ± 7.6% of contralateral value, respectively; mean ± SEM; p < 0.05). Posttraumatic hypothermia also significantly reduced iNOS activity at 7 days compared with normothermic rats (0.021 ± 0.06 and 0.23 ± 0.06 pmol/mg of protein/min, respectively; p < 0.05). The present results indicate that hypothermia (a) decreases early cNOS activation after TBI, (b) preserves cNOS activity at later periods, and (c) prevents the delayed induction of iNOS. Temperature‐dependent alterations in cNOS and iNOS enzymatic activities may participate in the neuroprotective effect of hypothermia in this TBI model

Role of nitric oxide in traumatic brain injury in the rat

Object. Although nitric oxide (NO) has been shown to play an important role in the pathophysiological process of cerebral ischemia, its contribution to the pathogenesis of traumatic brain injury (TBI) remains to be clarified. The authors investigated alterations in constitutive nitric oxide synthase (NOS) activity after TBI and the histopathological response to pharmacological manipulations of NO. Methods. Male Sprague—Dawley rats underwent moderate (1.7–2.2 atm) parasagittal fluid-percussion brain injury. Constitutive NOS activity significantly increased within the ipsilateral parietal cerebral cortex, which is the site of histopathological vulnerability, 5 minutes after TBI occurred (234.5 ± 60.2% of contralateral value [mean ± standard error of the mean {SEM}], p < 0.05), returned to control values by 30 minutes (114.1 ± 17.4%), and was reduced at 1 day after TBI (50.5 ± 13.1%, p < 0.01). The reduction in constitutive NOS activity remained for up to 7 days after TBI (31.8 ± 6.0% at 3 days, p < 0.05; 20.1 ± 12.7% at 7 days, p < 0.01). Pretreatment with 3-bromo-7-nitroindazole (7-NI ) (25 mg/kg), a relatively specific inhibitor of neuronal NOS, significantly decreased contusion volume (1.27 ± 0.17 mm3 [mean ± SEM], p < 0.05) compared with that of control (2.52 ± 0.35 mm3). However, posttreatment with 7-NI or pre- or posttreatment with nitro-l-arginine-methyl ester (l-NAME) (15 mg/kg), a nonspecific inhibitor of NOS, did not affect the contusion volume compared with that of control animals (1.87 ± 0.46 mm3, 2.13 ± 0.43 mm3, and 2.18 ± 0.53 mm3, respectively). Posttreatment with l-arginine (1.1 ± 0.3 mm3, p < 0.05), but not 3-morpholino-sydnonimine (SIN-1) (2.48 ± 0.37 mm3), significantly reduced the contusion volume compared with that of control animals. Conclusions. These data indicate that constitutive NOS activity is affected after moderate parasagittal fluid percussion brain injury in a time-dependent manner. Inhibition of activated neuronal NOS and/or enhanced endothelial NOS activation may represent a potential therapeutic strategy for the treatment of TBI

Anaplastic hemangiopericytoma manifesting as a rapidly enlarging extracranial mass lesion

We, herein, present a patient with a recurrent anaplastic hemanigiopericytoma manifesting as a rapidly enlarging extracranial mass lesion, which was revealed by pathological and intraoperative findings. In practice, this case highlights the mandatory need for a careful long-term follow-up for patients with hemangiopericytoma, since recurrence with a greater degree of malignancy can develop following an extended disease-free interval, as such knowledge will be helpful for planning the optimal surgical procedures

Complex and continuous change in hypothetic risk of rupture of intracranial cerebral aneurysms – Bleb mandala –

Background: This study of the intraoperative microscopic findings indicated complex behavior of aneurysmal bleb affects the rupture risk. Methods: A total of 300 consecutive relatively small (mean 6.2 mm) unruptured ICAs were clipped from July 2005 to January 2019. Microscopically identified blebs were divided into four types based on external appearances. Type A bleb was a thick-walled bleb. Type B bleb was a thin-walled reddish bleb. Type C bleb was a healing organized bleb. Type D was a hemosiderin-laden bleb. Type B and D blebs were considered to be risky blebs for rupture. ICAs with bleb(s) were further categorized into two types, stable aneurysms and unstable aneurysms with Type B and/or D bleb(s). The number and nature of the blebs were compared with the demographic data of the patients and radiological findings of the ICAs to evaluate possible predictors of the hypothetic rupture risk. Results: Aneurysms tended to enlarge as the number of blebs increased (p = 0.073). High risk Type B bleb had significantly larger number of blebs (p < 0.05). Healing Type C bleb was significantly more common in the group with two blebs than one bleb (p < 0.01). No significant differences were found between stable and unstable aneurysms in aneurysm multiplicity, size, and radiological bleb. Conclusions: Aneurysm state continuously changes due to the dynamic change of bleb number and nature. Our data suggests the necessity of new repeatable vessel-wall imaging technology to select risky unstable ICAs for treatment