Influence of deposition rate on magnetic properties of inverse-spinel NiCo2O4epitaxial thin films grown by pulsed laser deposition

We investigated the influence of the deposition rate on structural and magnetic properties of inverse-spinel ferrimagnet NiCo₂O₄ epitaxial films grown by pulsed laser deposition. While films' lattice constants are insensitive to the deposition rate, saturation magnetization, and perpendicular magnetic anisotropy for the film grown with a high deposition rate are reduced. These results imply that growing NiCo₂O₄ films with a high deposition rate leads to occupations of the tetrahedral site by Ni, although Ni ideally occupies only the octahedral site. Controlling the deposition rate and modulating the cation distribution is the key for tuning the magnetic properties in NiCo₂O₄ films

Estimated pretreatment hemodynamic prognostic factors of aneurysm recurrence after endovascular embolization.

BACKGROUND:Hemodynamic factors play important roles in aneurysm recurrence after endovascular treatment. OBJECTIVE:Predicting the risk of recurrence by hemodynamic analysis using an untreated aneurysm model is important because such prediction is required before treatment. METHODS:We retrospectively analyzed hemodynamic factors associated with aneurysm recurrence from pretreatment models of five recurrent and five stable posterior communicating artery (Pcom) aneurysms with no significant differences in aneurysm volume, coil packing density, or sizes of the dome, neck, or Pcom. Hemodynamic factors of velocity ratio, flow rate, pressure ratio, and wall shear stress were investigated. RESULTS:Among the hemodynamic factors investigated, velocity ratio and flow rate of the Pcom showed significant differences between the recurrence group and stable group (0.630 ± 0.062 and 0.926 ± 0.051, P= 0.016; 56.4 ± 8.9 and 121.6 ± 6.7, P= 0.008, respectively). CONCLUSIONS:Our results suggest that hemodynamic factors may be associated with aneurysm recurrence among Pcom aneurysms. Velocity and flow rate in the Pcom may be a pretreatment prognostic factor for aneurysm recurrence after endovascular treatment

Retroperitoneal lymphatic malformation causing scrotal swelling– a useful diagnostic work-up with two-phase MRI to differentiate from scrotal lymphatic malformation or abdomino-scrotal hydrocele

Background: Lymphatic malformation (LM) is an abnormal collection of lymphatic fluid within cysts or channels. LM can occur in any part of the body, but LM leading to scrotal swelling is very rare, and this unusual location often leads to diagnostic errors because the most common cause of a scrotal cystic lesion is a hydrocele. In the case presented here, a previously healthy 3-year-old boy recently developed a left scrotal swelling clinically mimicking a communicating hydrocele. However, a diagnostic laparoscopy showed a cystic lesion at the left internal inguinal ring with a closed internal inguinal ring, which is not an expected finding of communicating hydrocele. Differential diagnoses at surgery were scrotal LM, retroperitoneal LM, or abdomino-scrotal hydrocele (ASH). Two phase MRI performed both at the time of scrotal swelling and scrotal non-swelling showed a retroperitoneal LM bulging into the scrotum via the inguinal canal. Therefore, the retroperitoneal LM was completely resected using the inguinal approach. Conclusion: LM causing scrotal cystic lesion is rare, and it requires a high index of suspicion to make the correct diagnosis. Laparoscopy was needed to rule out the communicating hydrocele, and two-phase MRI was very useful to differentiate retroperitoneal LM causing scrotal swelling from scrotal LM or ASH. Both examinations helped with diagnosis and treatment planning.Chizue Ichijo, Shohei Takami, Kan Suzuki, Jun Fujishiro, Miho Watanabe, Retroperitoneal lymphatic malformation causing scrotal swelling– a useful diagnostic work-up with two-phase MRI to differentiate from scrotal lymphatic malformation or abdomino-scrotal hydrocele, Journal of Pediatric Surgery Case Reports, Volume 64, 2021, 101701, ISSN 2213-5766, https://doi.org/10.1016/j.epsc.2020.101701

Altered Hemodynamics Associated with Pathogenesis of the Vertebral Artery Dissecting Aneurysms

The etiology of the vertebral dissecting aneurysms is largely unknown, and they frequently occurs in relatively healthy young men. Objectives and Methods. A series of 57 consecutive cases defined by angiography were evaluated with regard to deviation in the course of the affected and contralateral vertebral arteries. Division was into 3 types: Type I without any deviation, Type II with mild-to-moderate deviation but not over the midline; and Type III with marked deviation over to the contralateral side beyond the midline. Results. The most frequent type of VA running was Type III for the affected and Type I nonaffected side, with this being found in all 17 patients except one. All of the Type III dissections occurred just proximal to a tortuous portion, while in cases with Type-I- and Type-II-affected sides, the majority (33 of 39) occurred near the union of the vertebral artery. In 10 of 57, a non-dominant side was affected, all except one being of Type I or II. With 12 recent patients assessed angiographically in detail for hemodynamics, eleven patients showed contrast material retrograde inflowing into the pseudolumen from the distal portion of the dissection site. Turbulent blood flow was recognized in all of these patients with retrograde inflow. Conclusions. Turbulent blood flow is one etiology of vertebral artery dissection aneurysms, with the sites in the majority of the cases being just proximal to a tortuous portion or union of vessels. In cases with dissection proximal to the tortuous course of the vertebral artery, retrograde inflow will occur more frequently than antegrade, which should be taken into account in designing therapeutic strategies

Spectral responses of GaAs photodiodes fabiricated by rapid thermal diffusion

The spectral responses of GaAs photodiodes fabricated by rapid thermal diffusion (RTD) of Zn are presented. The authors tried controlling the p+-n junction depth by the heating rate of RTD, without extending the diffusion time. It is found that Zn diffuses from the surface to a deeper position as the heating rate increases. Consequently, the spectral response of photodiodes formed by RTD is strongly dependent on the heating rate of RTD. A large improvement in the short-wavelength response between 400 and 800 nm is observed as the heating rate decreases

Real-time observation of picosecond-timescale optical quantum entanglement toward ultrafast quantum information processing

Entanglement is a fundamental resource of various optical quantum-information-processing (QIP) applications. Towards high-speed QIP system, entanglement should be encoded in short wavepackets. We report real-time observation of ultrafast optical Einstein-Podolsky-Rosen (EPR) correlation at a picosecond timescale in a continuous-wave (CW) system. Optical phase-sensitive amplification using 6-THz-bandwidth waveguide-optical-parametric amplifier enhances the effective efficiency of 70-GHz-bandwidth homodyne detectors, mainly used in 5th-generation telecommunication, enabling its use in real-time quantum-state measurement. While power measurement using frequency scanning, i.e., optical spectrum analyzer, is not performed in real-time, our observation is demonstrated through real-time amplitude measurement and can be directly employed in QIP applications. Observed EPR states show quantum correlation of 4.5 dB below shotnoise level encoded in wavepackets with 40-ps period, equivalent to 25-GHz repetition -- ${10^3}$ times faster than previous entanglement observation in CW system. The quantum correlation of 4.5 dB is already sufficient for several QIP applications, and our system can be readily extended to large-scale entanglement. Moreover, our scheme has high compatibility with optical communication technology such as wavelength-division multiplexing, and femtosecond-timescale observation is also feasible. Our demonstration is paradigm shift in accelerating accessible quantum correlation, the foundational resource of all quantum applications, from the nanosecond to picosecond timescale, enabling ultra-fast optical QIP.Comment: 14 pages, 4 figure