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Using a molecular beam epitaxy technique, we experimentally demonstrate a multiferroic heterostructure consisting of metastable ferromagnetic Co 3 Mn on piezoelectric Pb(Mg 1 / 3 Nb 2 / 3 )O 3 –PbTiO 3 (PMN-PT). Inserting a 2-nm-thick Fe layer between Co 3 Mn and PMN-PT(001) allows the formation of bcc Co 3 Mn layers even at an extremely low growth temperature of ∼ 80 ° C. Upon increasing this temperature to 200 ° C, a bcc Co 3 Mn/Fe/PMN-PT(001) multiferroic heterostructure with a relatively large saturation magnetization of ∼ 1680 kA/m and an atomically flat interface is obtained, resulting in an obvious converse magnetoelectric (CME) effect. The large CME effect originates mainly from the strain-induced modulation of the magnetic anisotropy energy, supported by the first-principles calculations. [ABSTRACT FROM AUTHOR]

Using artificially controlled ferromagnet (FM)–semiconductor (SC) interfaces, we study the decay of the nonlocal spin signals with increasing temperature in SC-based lateral spin-valve devices. When more than five atomic layers of Fe are inserted at the FM/SC interfaces, the temperature-dependent spin injection/detection efficiency (P inj / det ) can be interpreted in terms of the T 3 2 law, meaning a model of the thermally excited spin waves in the FM electrodes. For the FM/SC interfaces with the insufficient insertion of Fe atomic layers, on the other hand, the decay of P inj / det is more rapid than the T 3 2 curve. Using magneto-optical Kerr effect measurements, we find that more than five atomic layers of Fe inserted between FM and SC enable us to enhance the ferromagnetic nature of the FM/SC heterointerfaces. Thus, the ferromagnetism in the ultra-thin FM layer just on top of SC is strongly related to the temperature-dependent nonlocal spin transport in SC-based lateral spin-valve devices. We propose that the sufficient ferromagnetism near the FM/SC interface is essential for high-performance FM–SC hybrid devices above room temperature. [ABSTRACT FROM AUTHOR]

Scanning transmission electron microscopy (STEM) and X-ray photoelectron spectroscopy analyses were combined to clarify the ultraviolet light-induced surface changes of WO 3 in air. Identical-location STEM (IL-STEM) analysis showed that the WO 3 particle surface was covered with an amorphous thin film after ultraviolet irradiation in air. X-ray photoelectron spectroscopy analysis showed that hydrocarbon decomposition and the formation of carboxyl/hydroxyl species occurred. These results suggested that the amorphous thin films consisted of photocatalytic oxidative species of hydrocarbon. The IL-STEM analysis could detect small light-induced changes. This technique will be useful for the microscopic characterization of photocatalysis or photoinduced hydrophilic conversion.

Prokaryotes organize intracellular compartments with protein-based organelles called encapsulins. Encapsulins with icosahedral symmetry can encapsulate specific cargo proteins mediated by targeting peptides or encapsulation-mediating domains. Encapsulins have been used in eukaryotic cells for bioengineering, vaccine development, and nanoparticle alignment. Their versatility makes them attractive for research; however, detailed structural information on encapsulins is crucial for further applied research. However, cargo proteins are randomly oriented inside the icosahedral encapsulins. The random orientation of cargo proteins presents a challenge for structural analysis that relies on averaging processes such as x-ray crystallography and cryo-electron microscopy (cryo-EM) single-particle imaging. Therefore, we aimed to accurately estimate the secondary structure content and elucidate the structure of cargo proteins inside the particle by measuring the circular dichroism (CD) spectra using vacuum ultraviolet circular dichroism (VUVCD) spectroscopy. Thus, the structure of the cargo protein inside encapsulin was evaluated. This approach could potentially set a standard for evaluating cargo proteins inside particles in future applied research on encapsulins., (© 2024 The Author(s). Chirality published by Wiley Periodicals LLC.)

Introduction/purpose: For gastric subepithelial lesions (GSELs) showing a hypoechoic mass (HM) on endoscopic ultrasonography (EUS) imaging, the utility of EUS-guided tissue acquisition using conventional fine-needle aspiration needles (EUS-TA-CFNAN) and the frequency of histological types remain unclear. This study aimed to examine this issue., Methods: This prospective observational study enrolled 291 consecutive patients who underwent EUS-TA-CFNAN for GSELs showing an HM (GSELHM) on EUS imaging. Immunohistochemical analysis was performed for all EUS-TA-CFNAN and surgically resected specimens. The main outcome measures were the technical results of EUS-TA-CFNAN and the frequency of histological types in GSELHM., Results: The endoscopic ultrasound-guided tissue acquisition using conventional fine-needle aspiration needle diagnosis rate for GSELHM was 80.1% (95% confidence interval [CI]: 75.0-84.5, 233/291). It was significantly lower for antrum (P = 0.004) and lesions smaller than 2 cm (P = 0.003). There were no adverse events. The immunohistochemical diagnoses of EUS-TA-CFNAN included 149 cases of gastrointestinal stromal tumour (GIST) (51.2%), 48 cases of leiomyoma (16.5%), 11 cases of schwannoma (3.8%), 8 cases of the ectopic pancreas (2.7%), 5 cases of subepithelial lesion like cancer (1.7%), 12 cases of other lesions (4.1%), and 58 cases of undiagnosable lesions (19.9%). The frequency of malignant or potentially malignant tumour in GSELHM was 55.0% (95% CI: 49.1-60.8, 160/291). Surgery was performed in 149 patients according to the conclusive EUS-TA-CFNAN results, in which the diagnostic accuracy of EUS-TA-CFNAN was 97.3% (95% CI: 94.7-99.9, 145/149)., Conclusion: The use of EUS-TA-CFNAN for GSELHMs is safe and accurate. Gastric subepithelial lesions showing a hypoechoic mass have a reasonably high possibility of containing malignant or potentially malignant tumours, including GISTs., (© 2024 Australasian Society for Ultrasound in Medicine.)

We systematically investigate the long- and short-range chemical order, lattice volume, and spontaneous magnetization in single-crystalline Fe 0.6 Al 0.4 compound thin films. The vapor-quenching method based on a molecular beam epitaxy technique is utilized to fabricate the single-crystalline Fe 0.6 Al 0.4 compound with the different B 2 long-range order parameter S. S was varied by the deposition temperature T d, and it increases with increasing T d . The lattice volume V decreased with increasing T d , while the tetragonal distortion, ∼4%, due to epitaxial strain were observed. The changes in S and V were accompanied with the change in the magnetic moment per Fe, μ Fe . μ Fe showed the monotonic decrease as a function of S whereas μ Fe monotonically increases with V . With considering tetragonal distortion, μ Fe - V relationship has a good agreement with the previous reports. The μ Fe - S relationship showed the steep decrease of μ Fe around S ∼ 0.6. In contrast to μ Fe - V relationship, μ Fe - S relationship does not match only from ours to previous studies but also among other reports. It implies the statistical number of the nearest-neighbor Fe-Fe bonds, i.e. S , cannot be an enough explanatory parameter. To clarify the structural origin of change in μ Fe , the short-range order (SRO) parameter inferred from the analysis of superlattice diffractions were introduced. They showed the clear difference for the films with high and low μ Fe . The results suggest that the transition from the long- to the SRO state plays the significant role on μ Fe ., (© 2023 IOP Publishing Ltd.)

Background/aims: For duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging, the utility of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types have not been the focus of previous literature. This study aimed to clarify this., Materials and Methods: This prospective observational study enrolled 22 consecutive patients who underwent endoscopic ultrasoundguided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass on endoscopic ultrasound. Immunohistochemical analysis was performed for all endoscopic ultrasound-guided fine-needle aspiration and surgically resected specimens. The main outcome measures were the technical results of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types of duodenal subepithelial lesions with hypoechoic mass., Results: Thirteen fine-needle aspiration specimens were obtained from the duodenal bulb and eight from the descending duodenal region. The puncture was not performed because of intervening vessels in one patient. The diagnostic rate was 81% (95% confidence interval: 58.1-94.6, 17/21 patients). In 12 patients receiving surgical resection (excluding one cancellation of endoscopic ultrasoundguided fine-needle aspiration), the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration was 75% (95% confidence interval: 42.8-94.5, 9/12 patients). No complications were observed. The histopathological diagnoses included 11 cases of gastrointestinal stromal tumor (50%), 2 cases of leiomyoma (9%), 2 cases of metastatic cancer (9%), 2 cases of benign inconclusive, and 1 case each of carcinoid, malignant lymphoma, leiomyosarcoma, gauzeoma, and aberrant pancreas (4.5% each). The frequency of malignant tumors in the duodenal subepithelial lesions with hypoechoic mass group was 73% (16/22 patients)., Conclusions: Endoscopic ultrasound-guided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass was safe and accurate. As duodenal subepithelial lesion with hypoechoic mass has a reasonably high possibility of containing malignant tumors, it is desirable to perform endoscopic ultrasound-guided fine-needle aspiration.

Endoscopic submucosal dissection (ESD) is a globally accepted minimally invasive therapy for early-stage gastrointestinal tract tumors. Although numerous electrosurgical knives have been developed for ESD, technical difficulties and high complication rates (bleeding and perforation) have limited their use worldwide. The grasping-type scissors forceps [clutch cutter (CC)] is the first forceps-type resection device developed with reference to hemostatic forceps. The aim was to allow easy and safe ESD throughout the gastrointestinal tract, as a biopsy technique, using one device. The CC can grasp the target tissue accurately and pull it away from the underlying muscle layer prior to energizing the tissue, for safe and effective incision and hemostasis during ESD. Reported clinical studies showed that ESD using the CC (ESD-CC) is a safe (perforation rate: 0%-3.6%; delayed bleeding rate: 0%-4.2%), technically efficient ( en-bloc resection rate: 88.9%-100%), and single-device method for dissecting early-stage gastrointestinal tract tumors. The ESD-CC technique is simple and easy to learn because it can be completed simply by repeating the grasp, pull, and coagulate and/or incise actions using an electrosurgical current. The reported self-completion rate by non-experts was significantly better with the CC than with conventional knives (61.7% vs 24.5%, respectively; P < 0.001). Furthermore, the CC is used for other endoscopic therapies, such as endoscopic polypectomy for large pedunculated polyps, endoscopic myotomy for Zenker's diverticulum, endoscopic treatment of buried bumper syndrome, and endoscopic necrosectomy for wall-off pancreatic necrosis. The initial reports using CC for these therapies have shown favorable results. In this review, we describe the structural features of the CC, how to use the instrument, efficacies of ESD-CC, and other unique endoscopic therapies using the CC., Competing Interests: Conflict-of-interest statement: Kazuya Akahoshi and Fujifilm have applied for a patent for the Clutch Cutter described in this article. Japan, China, and the European Union have already granted patents. Keishi Komori declares that he has no conflict of interest. Kazuaki Akahoshi declares that he has no conflict of interest. Shinichi Tamura declares that he has no conflict of interest. Shigeki Osada declares that he has no conflict of interest. Yuki Shiratsuchi declares that she has no conflict of interest. Masaru Kubokawa declares that he has no conflict of interest., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

Magnetoelectric (ME) effect is a type of cross-coupling between unconjugated physical quantities, such as the interplay between magnetization and electric field. The ME effect requires simultaneous breaking of spatial and time inversion symmetries, and it sometimes appears in specific antiferromagnetic (AFM) insulators. In recent years, there has been a growing interest for applying the ME effect to spintronic devices, where the effect is utilized as an input method for the digital information. In this article, we review the recent progress of this scheme mainly based on our own achievements. We particularly focus on several fundamental issues, including the ME control of the AFM domain state, which is detectable through the perpendicular exchange bias polarity. The progress made in understanding the switching mechanism, interpretation of the switching energy, switching dynamics, and finally, the future prospects are included., (© 2021 IOP Publishing Ltd.)

Opinion Statement: With the widespread use of esophagogastroduodenoscopy in recent years, the detection rate of superficial non-ampullary duodenal epithelial tumors (SNADETs) is increasing. Most SNADETs are early-stage adenocarcinoma or benign conditions, including adenoma. Therefore, endoscopic resection is desirable from the perspective of quality of life. However, endoscopic resection for SNADETs has not yet been established. Endoscopic submucosal dissection (ESD) is the most promising method for the treatment of SNADETs, because ESD provides a high rate of en bloc resection and a low rate of recurrence regardless of the tumor size. However, the difficulty of the procedure and a high rate of severe adverse events including perforation and bleeding have become major problems. Various preventive countermeasures for adverse events, such as use of specific devices, endoscope stabilization methods, and endoscopic closure of the post-ESD ulcer using clips, are reported to reduce the risk of the adverse events of ESD for SNADETs. This article reviews and highlights the current state of ESD for SNADETs and new challenges towards safe and effective ESD.

Background and Aims: The Clutch Cutter (CC) can grasp, pull, coagulate, and incise targeted tissue with the use of electrosurgical current. It was developed as a biopsy technique to reduce the technical difficulty of endoscopic submucosal dissection (ESD) with knives. The aim of this study was to evaluate the efficacy and safety of ESD using the CC (ESD-CC) for early colorectal epithelial neoplasms (ECENs)., Methods: In this prospective study, we enrolled 437 consecutive patients with a diagnosis of ECEN between January 2009 and January 2018. They all satisfied the Japanese colorectal cancer treatment guidelines for ESD; namely, confirmation by preliminary endoscopy, EUS, and endoscopic biopsy. The CC was used for all steps of ESD (mucosal incision, submucosal dissection, and hemostatic treatment); therapeutic efficacy and safety were assessed., Results: The en bloc resection rate was 99.3% (434/437), and the R0 resection rate was 87.0% (380/437). The mean operating time was 88.3 minutes. Perforation occurred in 10 cases (2.3%) and was managed with conservative medical treatment. Post-ESD-CC bleeding occurred in 10 cases (2.3%) and was successfully treated by endoscopic hemostatic treatment., Conclusions: ESD-CC is a technically efficient, safe, and easy method for resecting ECEN., (© 2019 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc.)

At the end of its life cycle, the cellular slime mold Dictyostelium discoideum forms a fruiting body consisting of spores and a multicellular stalk. Originally, the chlorinated alkylphenone differentiation-inducing factors (DIFs) -1 and -3 were isolated as stalk cell inducers in D. discoideum . Later, DIFs and their derivatives were shown to possess several biologic activities including antitumor and anti- Trypanosoma properties. In this study, we examined the antibacterial activities of approximately 30 DIF derivatives by using several bacterial species. Several of the DIF derivatives strongly suppressed the growth of the Gram-positive bacteria Staphylococcus aureus , Bacillus subtilis , and Enterococcus faecalis and Enterococcus faecium , at minimum inhibitory concentrations (MICs) in the sub-micromolar to low-micromolar range. In contrast, none of the DIF derivatives evaluated had any noteworthy effect on the growth of the Gram-negative bacterium Escherichia coli (MIC, >100 µM). Most importantly, several of the DIF derivatives strongly inhibited the growth of methicillin-resistant S. aureus and vancomycin-resistant E. faecalis and E. faecium . Transmission electron microscopy revealed that treatment with DIF derivatives led to the formation of distinct multilayered structures consisting of cell wall or plasma membrane in S. aureus . The present results suggest that DIF derivatives are good lead compounds for developing novel antimicrobials.

Aligned growth of transition metal dichalcogenides and related two-dimensional (2D) materials is essential for the synthesis of high-quality 2D films due to effective stitching of merging grains. Here, we demonstrate the controlled growth of highly aligned molybdenum disulfide (MoS 2 ) on c-plane sapphire with two distinct orientations, which are highly controlled by tuning sulfur concentration. We found that the size of the aligned MoS 2 grains is smaller and their photoluminescence is weaker as compared with those of the randomly oriented grains, signifying enhanced MoS 2 -substrate interaction in the aligned grains. This interaction induces strain in the aligned MoS 2 , which can be recognized from their high susceptibility to air oxidation. The surface-mediated MoS 2 growth on sapphire was further developed to the rational synthesis of an in-plane MoS 2 -graphene heterostructure connected with the predefined orientation. The in-plane epitaxy was observed by low-energy electron microscopy. Transmission electron microscopy and scanning transmission electron microscopy suggest the alignment of a zigzag edge of MoS 2 parallel to a zigzag edge of the neighboring graphene. Moreover, better electrical contact to MoS 2 was obtained by the monolayer graphene compared with a conventional metal electrode. Our findings deepen the understanding of the chemical vapor deposition growth of 2D materials and also contribute to the tailored synthesis as well as applications of advanced 2D heterostructures.