Core-Shell Perovskite Quantum Dots for Highly Selective Room-Temperature Spin Light-Emitting Diodes.

Circularly polarized light (CPL) is a crucial light source with a wide variety of potential applications such as magnetic recording, and 3D display. Here, core-shell heterostructured perovskite quantum dots (QDs) for room-temperature spin-polarized light-emitting diodes (spin-LEDs) are developed. Specifically, a 2D chiral perovskite shell is deposited onto the achiral 3D inorganic perovskite (CsPbBr3 ) core. Owing to the chiral-induced spin selectivity effect, the spin state of the injected charge carriers is biased when they are transmitted through the 2D chiral shell. The spin-controlled carriers then radiatively recombine inside the CsPbBr3 emissive core, resulting in CPL emission. It is demonstrated that the (R)- and (S)-1-(2-(naphthyl)ethylamine) (R-/S-NEA) 2D chiral cations enhance the spin polarization degree due to their strong chiroptical properties. Systematical defect analyses confirm that 2D chiral cations (i.e., R-/S-NEA) successfully passivate halide vacancies at the surface of the CsPbBr3 QDs, thereby attaining a high photoluminescence quantum yield of 78%. Moreover, the spin-LEDs prepared with core-shell QDs achieve a maximum external quantum efficiency of 5.47% and circularly polarized electroluminescence with a polarization degree (PCP-EL ) of 12% at room temperature. Finally, various patterns fabricated by inkjet printing the core-shell QDs emit strong CPL, highlighting their potential as an emitter for next-generation displays.

Chirality-Induced Spin Selectivity of Chiral 2D Perovskite Enabling Efficient Spin-Dependent Oxygen Evolution Reaction.

The sluggish and complex multi-step oxygen evolution reaction remains an obstacle to bias-free photoelectrochemical water-splitting systems. Several theoretical studies have suggested that spin-aligned intermediate radicals can significantly enhance the kinetic rates for oxygen generation. Herein, it is reported that the chirality-induced spin selectivity phenomena can become an impressive approach by adopting chiral 2D organic-inorganic hybrid perovskites as a spin-filtering layer on the photoanode. This chiral 2D perovskite-based water-splitting device achieves enhanced oxygen evolution performance with a reduced overpotential of 0.14 V, high fill factor, and 230% increased photocurrent compared to a device without a spin-filtering layer. Moreover, combined with a superhydrophobic patterning strategy, this device realizes excellent operational stability by sustaining ≈90% of the initial photocurrent, even after 10 h.

Unraveling chirality transfer mechanism by structural isomer-derived hydrogen bonding interaction in 2D chiral perovskite.

In principle, the induced chirality of hybrid perovskites results from symmetry-breaking within inorganic frameworks. However, the detailed mechanism behind the chirality transfer remains unknown due to the lack of systematic studies. Here, using the structural isomer with different functional group location, we deduce the effect of hydrogen-bonding interaction between two building blocks on the degree of chirality transfer in inorganic frameworks. The effect of asymmetric hydrogen-bonding interaction on chirality transfer was clearly demonstrated by thorough experimental analysis. Systematic studies of crystallography parameters confirm that the different asymmetric hydrogen-bonding interactions derived from different functional group location play a key role in chirality transfer phenomena and the resulting spin-related properties of chiral perovskites. The methodology to control the asymmetry of hydrogen-bonding interaction through the small structural difference of structure isomer cation can provide rational design paradigm for unprecedented spin-related properties of chiral perovskite.

Tailoring the Time-Averaged Structure for Polarization-Sensitive Chiral Perovskites.

Chiral perovskites have emerged as promising candidates for polarization-sensing materials. Despite their excellent chiroptical properties, the nature of their multiple-quantum-well structures is a critical hurdle for polarization-based and spintronic applications. Furthermore, as the origin of chiroptical activity in chiral perovskites is still illusive, the strategy for simultaneously enhancing the chiroptical activity and charge transport has not yet been reported. Here, we demonstrated that incorporating a Lewis base into the lattice can effectively tune the chiroptical response and electrical properties of chiral perovskites. Through solid-state nuclear magnetic resonance spectroscopic measurements and theoretical calculations, it was demonstrated that the material property manipulation resulted from the change in the time-averaged structure induced by the Lewis base. Finally, as a preliminary proof of concept, a vertical-type circularly polarized light photodetector based on chiral perovskites was developed, exhibiting an outstanding performance with a distinguishability of 0.27 and a responsivity of 0.43 A W-1.

Universal Bifacial Stamping Approach Enabling Reverse-Graded Ruddlesden-Popper 2D Perovskite Solar Cells.

Quasi 2D perovskite solar cells (PSCs) are promising light absorbers that overcome the inherent instabilities of 3D perovskites. High-performance and stable 2D PSCs require careful control over the crystallographic orientation and phase distribution. This study introduces a simple and universal bifacial stamping method to obtain highly oriented perovskite crystals with a reverse-graded structure, where the low-n-value 2D perovskite phases are located mainly at the film surfaces. Bifacial stamping of 3D perovskite films atop the 2D films enables incorporation of 2D spacer cations into the 3D film surfaces, forming reverse-graded quasi-2D perovskite films. During stamping, suppressed evaporation of the precursor solvent induces heterogeneous nucleation from the contact interface between the 2D and 3D films, resulting in well-crystallized perovskite films having out-of-plane alignments with respect to the substrate. Thus, a highly oriented and reverse-graded quasi-2D perovskite with an average n value of 18 is obtained with power conversion efficiency exceeding 17% and high open-circuit voltage of 1.11 V for iso-butylammonium (iso-BA)-based (iso-BA2 MAn -1 Pbn I3 n +1 ) PSCs. The unencapsulated device retains 92% of its initial efficiency after aging at 40 ± 5% relative humidity for 1200 h. This work provides a new strategy for fabricating highly oriented and phase-controlled quasi-2D PSCs.

[A case of cerebral venous sinus thrombosis following the vaccination with Tozinameran].

A 31-year-old man visited our hospital due to experiencing severe headaches, vomiting, and hypesthesia in the left side of his body. He had no past illnesses and had had no severe headaches before. The symptoms started the day after receiving the coronavirus disease 2019 (COVID-19) vaccination with Tozinameran. An MRI revealed cerebral venous sinus thrombosis and high intensity (DWI & FLAIR) of the right thalamus. Anticoagulant therapy was initiated, and his symptoms improved gradually. The follow-up MRI showed recanalization in a large part of the occluded venous sinuses. Most of the coagulation tests were normal, except for slightly high value of D-dimer, and the polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was negative. Further cases are needed to judge if there is some sort of relationship between the vaccination and the cerebral venous sinus thrombosis.

Comparison of the Physical Characteristics of Support Stents for Cerebral Aneurysm Embolization.

Objective: There is a limited understanding of the characteristics of individual intracranial stents used for aneurysm treatment. We used an experimental model to evaluate the physical characteristics of support stents for aneurysm embolization. Methods: Enterprise 2 VRD 4.0 × 39 mm, Neuroform Atlas 4.5 × 21 mm, and LVIS 4.5 × 32 mm stents were: 1) observed under light microscopy and subjected to measurements of 2) circumferential radial force, 3) strut tension, 4) stent compression, and 5) conformability upon bending. Results: 1) Light microscopy showed a large structural difference between laser-cut (Enterprise 2 VRD, Neuroform Atlas) and braided (LVIS) stents. 2) Within the range of indicated blood vessel diameters, the radial force of Enterprise 2 VRD was higher than that of Neuroform Atlas. An extremely large force was required to decrease the LVIS diameter. 3) Neuroform Atlas easily deformed compared to Enterprise 2 VRD, while LVIS was extended with a smaller traction force than that required for Neuroform Atlas. 4) The compression strength was in the order of Enterprise 2 VRD >Neuroform Atlas >LVIS. 5) Enterprise 2 VRD showed a decreased cell area on the concave side, and Neuroform Atlas showed deformation with overlapping struts on the concave side. LVIS naturally adhered to the wall of the blood vessel model. Conclusion: Laser-cut and braided stents showed different physical characteristics that were visualized and shown as numerical data. These findings improve the understanding of the proper use of these stents in clinical applications.

Molecular status of pituitary carcinoma and atypical adenoma that contributes the effectiveness of temozolomide.

There have been several reports of temozolomide (TMZ) treatment of pituitary carcinomas and atypical adenomas. O(6)-methyl-guanine-DNA methyltransferase is not the sole molecule determining the sensitivity to TMZ in pituitary carcinomas and atypical adenomas. The Japan Society of Hypothalamic and Pituitary Tumors study suggests that MSH6, one of mismatch repair pathway enzyme, fulfills a contributory role to the efficacy of TMZ treatment for pituitary carcinomas and atypical adenomas. The preserved MSH6 function might be essential for the responsiveness to TMZ treatment in pituitary carcinomas and atypical adenomas.

Low-voltage-tunable nanobeam lasers immersed in liquid crystals.

A low-voltage-tunable one-dimensional nanobeam laser is realized by employing lithographically defined lateral electrodes. An InGaAsP nanobeam with a sub-micrometer width is transfer-printed in the middle of two electrodes using a polydimethylsiloxane stamp. Spectral tuning is achieved by controlling the molecular alignment of the surrounding liquid crystals (LCs). From µm-scale-gap structures, a total wavelength shift that exceed 6 nm is observed at a low voltage of less than 10 V. A measured spectral tuning rate of 0.87 nm/V, which is the largest value ever reported to our knowledge among LC-tuned photonic crystal lasers, was also noted.

Clinicopathological and molecular histochemical review of skull base metastasis from differentiated thyroid carcinoma.

Skull base metastasis from differentiated thyroid carcinoma including follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) is a rare clinical entity. Eighteen FTC cases and 10 PTC cases showing skull base metastasis have been reported. The most common symptom of skull base metastasis from FTC and PTC is cranial nerve dysfunction. Bone destruction and local invasion to the surrounding soft tissues are common on radiological imaging. Skull base metastases can be the initial clinical presentation of FTC and PTC in the presence of silent primary sites. The possibility of skull base metastasis from FTC and PTC should be considered in patients with the clinical symptoms of cranial nerve dysfunction and radiological findings of bone destruction. A variety of genetic alterations in thyroid tumors have been identified to have a fundamental role in their tumorigenesis. Molecular histochemical studies are useful for elucidating the histopathological features of thyroid carcinoma. Recent molecular findings may provide novel molecular-based treatment strategies for thyroid carcinoma.

Urinary growth hormone level and insulin-like growth factor-1 standard deviation score (IGF-SDS) can discriminate adult patients with severe growth hormone deficiency.

Adult growth hormone (GH) deficiency (AGHD) in Japan is diagnosed based on peak GH concentrations during GH provocative tests such as GHRP-2 stimulation test. In this study, we aimed to evaluate the ability of serum insulin-like growth factor-1 (sIGF-1) and urinary GH (uGH) at the time of awakening to diagnose AGHD. Fifty-nine patients with pituitary disease (32 men and 27 women; age 20-85 y (57.5 ± 15.5, mean ± SD) underwent GHRP-2 stimulation and sIGF-1 testing. Thirty-six and 23 patients were diagnosed with and without severe AGHD, respectively based on a peak GH response of <9 ng/mL to GHRP-2 stimulation. Serum IGF-1 was evaluated as a standard deviation score (IGF-1 SDS) based on age and sex. We determined whether uGH levels in urine samples from 42 of the 59 patients at awakening were above or below the sensitivity limit. We evaluated IGF-1 SDS and uGH levels in a control group of 15 healthy volunteers. Values for IGF-1 SDS were significantly lower in patients with, than without (-2.07 ± 1.77 vs.-0.03 ± 0.92, mean ± SD; p < 0.001) AGHD whereas the range of IGF-1 SDS substantially overlapped at > -1.4. IGF-1 SDS discriminated AGHD more effectively in patients aged ≤60 years. The χ2 test revealed a statistical relationship between uGH and AGHD (test statistic: 7.0104 ≥ χ2 (1; 0.01) = 6.6349). When IGF-1 SDS is < -1.4 or uGH is below the sensitivity limit, AGHD can be detected with high sensitivity.

Preservation of the lesser occipital nerve during microvascular decompression for hemifacial spasm. Technical note.

The authors report on their technique for preserving the lesser occipital nerve (LON) during lateral suboccipital craniotomy. In their technique, the LON, which runs along the surface of or just beneath the sternocleidomastoid muscle, is identified and preserved. Lesser occipital nerve preservation using their technique was attempted in 25 patients who underwent microvascular decompression for hemifacial spasm. The LON was successfully preserved in 16 of these patients, was impossible to preserve in two patients, and could not be identified in seven patients. Among the patients in whom LON preservation was successful, 87.5% were free of sensory disturbance 6 months after surgery, whereas both patients in whom the LON could not be preserved complained of sensory disturbances in the occipital area and the posterior part of the auricula. Fifty-seven percent of the patients whose LON could not be identified complained of sensory disturbance. Thus, this technique for preserving the LON reduces the incidence of sensory disturbance in the occipital region after suboccipital craniotomy for microvascular decompression for hemifacial spasm.

Pituitary cyst presenting with hyponatremia and increased secretion of brain natriuretic peptide. Case report.

In most cases of pituitary cyst there are no clinical symptoms and the lesions are found incidentally. The authors report the case of a 60-year-old man with a pituitary cyst causing visual disturbance and hyponatremia. The patient presented with appetite loss and general fatigue. On admission, blood workup showed severe hyponatremia (112 mEq/L), and bitemporal hemianopsia was observed on neurological examination. Magnetic resonance imaging revealed an intra- and suprasellar region cystic mass extending to the frontal base and hypothalamic area. The serum level of brain natriuretic peptide (BNP) was elevated (92 pg/ml) with polyuria and excessive Na excretion. Transsphenoidal surgery was performed to drain the cyst. The cyst wall was partially excised and the cystic fluid was aspirated. The secretion of BNP normalized postoperatively, and the hyponatremia and visual symptoms resolved. Histological examination, including an electron microscopy study, confirmed the diagnosis of a simple cyst. This appears to be the first reported case of a pituitary simple cyst associated with hyponatremia and an elevated BNP level.