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Transparent low-melting inorganic glass is an attractive industrial material based on its high thermal and light resistance compared with conventional engineering plastics. If the melting temperature of inorganic glass could be decreased, the doping of guest materials or compression moulding on the glass surface would be easier. Although phosphate glass is considered as a potential candidate because of its transparency in the visible region and low-melting behaviour, water durability often becomes a problem for implementation. Here, we prepared inorganic low-melting phosphate glass at a temperature of 500 °C via a melting and quenching methodology. It was found that tin-doped phosphate glasses exhibited higher thermal and light resistance properties than polycarbonates. Colourless transparent oxide glasses without organic components are capable of bringing about new possibilities for the application of inorganic glasses.

Recently, spark plasma sintering (SPS) has become an attractive method for the preparation of solid-state ceramics. As SPS is a pressure-assisted low-temperature process, it is important to examine the effects of temperature and pressure on the structural properties of the prepared samples. In the present study, we examined the correlation between the preparation conditions and the physical and structural properties of SiO 2 glasses prepared by SPS. Compared with the conventional SiO 2 glass, the SPS-SiO 2 glasses exhibit a higher density and elastic modulus, but a lower-height first sharp diffraction peak of the X-ray total structure factor. Micro-Raman and micro-IR spectra suggest the formation of heterogeneous regions at the interface between the SiO 2 powders and graphite die. Considering the defect formation observed in optical absorption spectra, reduction reaction mainly affects the densification of SPS-SiO 2 glass. Hence, the reaction at the interface is important for tailoring the structure and physical properties of solid-state materials prepared by the SPS technique.

Diagnostic image analysis for unruptured cerebral aneurysms using artificial intelligence has a very high sensitivity. However, further improvement is needed because of a relatively high number of false positives. This study aimed to confirm the clinical utility of tuning an artificial intelligence algorithm for cerebral aneurysm diagnosis. We extracted 10,000 magnetic resonance imaging scans of participants who underwent brain screening using the “Brain Dock” system. The sensitivity and false positives/case for aneurysm detection were compared before and after tuning the algorithm. The initial diagnosis included only cases for which feedback to the algorithm was provided. In the primary analysis, the sensitivity of aneurysm diagnosis decreased from 96.5 to 90% and the false positives/case improved from 2.06 to 0.99 after tuning the algorithm ( P  < 0.001). In the secondary analysis, the sensitivity of aneurysm diagnosis decreased from 98.8 to 94.6% and the false positives/case improved from 1.99 to 1.03 after tuning the algorithm ( P  < 0.001). The false positives/case reduced without a significant decrease in sensitivity. Using large clinical datasets, we demonstrated that by tuning the algorithm, we could significantly reduce false positives with a minimal decline in sensitivity.

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Background Spontaneous intracranial hypotension (SIH) is secondary to a cerebrospinal fluid leak at the spinal level without obvious causative events. Several signs on brain and cervical spine magnetic resonance (MR) imaging (MRI) have been associated with SIH but can be equivocal or negative. This retrospective study sought to identify characteristic SIH signs on thoracic spinal MRI. Methods Cranial and spinal MR images of 27 consecutive patients with classic SIH symptoms, who eventually received epidural autologous blood patches (EBPs), were analyzed. Results The most prevalent findings on T2-weighted MRI at the thoracic level were anterior shift of the spinal cord (96.3%) and dorsal dura mater (81.5%), probably caused by dural sac shrinkage. These dural sac shrinkage signs (DSSS) were frequently accompanied by cerebrospinal fluid collection in the posterior epidural space (77.8%) and a prominent epidural venous plexus (77.8%). These findings disappeared in all six patients who underwent post-EBP spinal MRI. Dural enhancement and brain sagging were minimum or absent on the cranial MR images of seven patients, although DSSS were obvious in these seven patients. For 23 patients with SIH and 28 healthy volunteers, a diagnostic test using thoracic MRI was performed by 13 experts to validate the usefulness of DSSS. The median sensitivity, specificity, positive-predictive value, negative-predictive value, and accuracy of the DSSS were high (range, 0.913–0.931). Conclusions Detection of DSSS on thoracic MRI facilitates an SIH diagnosis without the use of invasive imaging modalities. The DSSS were positive even in patients in whom classic cranial MRI signs for SIH were equivocal or minimal.

In breast cancer surgery, some medical facilities lack the necessary resources to conduct sentinel lymph node biopsy and its intraoperative frozen section consultation. In the coastal rural area of Fukushima, Japan, which has suffered from physician undersupply following the 2011 triple disaster of earthquake, tsunami and nuclear disaster, we explored the feasibility of telepathology by evaluating the diagnostic accuracy in remote intraoperative frozen section consultation of sentinel lymph node biopsy and its required time. Although examination time has room for improvement, telepathology can be one possible solution in resource-limited areas.

BackgroundThe discoid lateral meniscus (DLM) is a unique anatomical variant characterized by a larger, thicker lateral meniscus. For clinical diagnosis of DLM, coronal and sagittal slices in two-dimensional (2D) MRI and arthroscopic imaging are typically employed. However, evaluating the entire shape of the DLM is challenging due to the limited views and details provided by these methods. Three-dimensional (3D) visualization with MRI offers a more comprehensive view of the entire meniscus. The purpose of this study was to demonstrate the entire shape of a DLM using 3D images and unveil its unique characteristics.MethodsThe study population consisted of 31 knees diagnosed with DLM through arthroscopic examination at our hospital between 2017 and 2021. This group comprised 20 males (65%) and 11 females (35%), with ages ranging from 9 to 49 years (mean age, 24.2 years). Furthermore, a control group of 43 knees without DLM was included for comparative analysis. This control group consisted of 22 males (51%) and 21 females (49%), with ages ranging from 9 to 69 years (mean age, 28.5 years). 3D images of the medial meniscus (MM) and lateral meniscus (LM) were reconstructed from 1.5T-MRI images with semi-automatic segmentation using free software. From the coordinate information, the anterior-to-posterior lengths of the MM and LM were obtained, and the medial-to-lateral anterior-to-posterior length (L/M ratio) ratio was calculated and compared with the value of the non-DLM population.ResultsOur method allows for the detailed delineation of the DLM's unique morphology. The DLM group exhibited a significantly smaller L/M ratio compared to the non-DLM group (DLM: 0.66±0.06, non-DLM: 0.74±0.05, p<0.001).ConclusionsReconstructed 3D images could help to demonstrate the whole morphology of DLM and reveal its unique features, in which DLM shows a significantly smaller L/M ratio as compared to non-DLM.

In elderly populations, the enlargement of the perivascular space is related to small vessel disease and the glymphatic system. Enlarged perivascular spaces (EPVS) in the basal ganglia (EPVS–BG) and EPVS in the centrum semiovale (EPVS–CSO) are associated with different pathophysiological processes. However, the prevalence of EPVS and the factors associated with EPVS location in healthy middle-aged individuals are still unclear. We aimed to determine the prevalence of EPVS and the factors associated with EPVS location among healthy individuals in their 40 s This study included 5000 consecutive healthy individuals who underwent screening for brain diseases in Japan from August to December 2018. Of them, the data of individuals in their 40 s were extracted and analyzed. The associations of age, sex, body mass index, smoking and drinking history, and medical history with EPVS location were investigated. Similar analyses were performed for the other age groups. A literature review on the factors associated with EPVS location was also performed. A total of 1720 individuals in their 40 s were finally included. The prevalence of EPVS–BG and EPVS–CSO was 7.7% and 9.2%, respectively. Age (years), smoking history, and hypertension were associated with EPVS–BG; none of the studied factors were found to be associated with EPVS–CSO. In the elderly, the factors previously reported to be associated with EPVS–BG included atherosclerosis change, while the factors associated with EPVS–CSO were cerebral amyloid angiopathy-related formation. Both EPVS–BG and EPVS–CSO occurred among healthy individuals in their 40 s, but they did so rarely, and less prevalently than in older age groups. EPVS–BG and EPVS–CSO may represent early imaging signs of the atherosclerotic and cerebral amyloid angiopathy processes, respectively. The anonymized data for this study will be shared upon any qualified investigator’s request to the corresponding author. Primary data from this study will be made available upon reasonable request in accordance with the review board of the research institute. •Enlarged perivascular spaces (EPVS) are understudied in healthy middle-aged subjects.•This study focused on the basal ganglia (EPVS–BG) and centrum semiovale (EPVS–CSO).•Enlarged perivascular spaces rarely occur among healthy middle-aged individuals.•EPVS–BG is associated with atherosclerosis-related demographic and clinical factors.•EPVS may be early imaging signs of atherosclerosis or cerebral amyloid angiopathy.

Spherical bismuth nanoparticles were prepared by stirring a solution of bismuth trichloride and polyvinylpyrrolidone in ethylene glycol at 190 C followed by the addition of sodium hydroxide and quenching in ice-cooled ethylene glycol. The nanosphere diameter increased with increasing sodium hydroxide addition. Platelike nanoparticles were obtained by adding ferric chloride and sodium hydroxide prior to quenching. The crystalline axes of the nanospheres, dispersed in polysiloxane, were orientated under high magnetic fields, attributed to the anisotropic susceptibility of bismuth. Nanospheres or nanoplatelets were dispersed in methyl methacrylate monomer, and orientated by an 8 T magnetic field during polymerisation. The optical transmittance of the resulting nanocomposites varied according to the orientation relative to the applied magnetic field, attributed to the anisotropy of the dielectric constants and to the shape of the nanoplatelets.

The structure and optical properties of phosphate glasses containing bismuth or niobium oxides for subwavelength structure (SWS) optical elements were studied. The glasses containing a large amount of bismuth and niobium oxides had refractive indexes higher than 1.8 and low deformation temperatures. However, these high refractive index glasses were yellowish due to the electronic transition in trivalent bismuth ions and pentavalent niobium ions. The structure of the glasses was investigated by X-ray, IR, and Raman spectroscopy. NbOx and BiOx formed clusters as the bismuth and niobium oxide content increased. The results showed that the local structure around bismuth and niobium ions was related to the coloration. Based on these results, we developed high refractive index glasses that were used for precision molding to fabricate periodic SWSs. One-dimensional periodic SWSs were fabricated on the glass surface by a precision molding method using a SiC mold on which the reverse of the SWS pattern was carved and a flat SiC mold. One-dimensional SWSs with a high aspect ratio were fabricated on one surface of the glass plate. The niobium phosphate glass plates with the one-dimensional SWS showed phase retardation higher than 1/8l between TE- and TM-polarized beams at 400 nm, demonstrating that a wavelength plate can be fabricated by our precision molding technique.