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We discuss the structure of threading dislocations in α-Ga2O3 thin films grown on c- and m-plane sapphire substrates. The thickness-dependent threading dislocation density in both films directly affects the electrical properties of the films including carrier concentration and mobility. Two distinct types of threading dislocations are identified for each of the c- and m-plane α-Ga2O3 thin films. The c-plane α-Ga2O3 thin film shows Burgers vectors of 1 / 3 [ 1 1 ¯ 01 ] and 1 / 3 [ 11 2 ¯ 0 ] , while the m-plane α-Ga2O3 thin film displays Burgers vectors of 1 / 3 [ 2 1 ¯ 1 ¯ 0 ] and 1 / 3 [ 1 1 ¯ 01 ]. This paper presents a detailed structure of the threading dislocations in α-Ga2O3, which has been little disclosed thus far mainly due to the difficulty in synthesizing the metastable α-Ga2O3. [ABSTRACT FROM AUTHOR]

Rutile-type GeO2 (r-GeO2) with an ultrawide bandgap of ∼4.7 eV has emerged as a promising material for next-generation power-electronic and optoelectronic devices. We performed transmission electron microscopy (TEM) observation to analyze the structural properties of r-GeO2 film on r-TiO2 (001) substrate at an atomic level. The r-GeO2 film exhibits a threading dislocation density of 3.6 × 109 cm−2 and there exist edge-, screw-, and mixed-type dislocations in the film as demonstrated by two-beam TEM. The edge-type dislocations have Burgers vectors of [100] and/or [110]. The bandgap of the r-GeO2 film is 4.74 ± 0.01 eV as determined by electron energy loss spectroscopy. [ABSTRACT FROM AUTHOR]

Ellis-van Creveld syndrome (EVC) is a rare disorder with marked valgus knee deformity, and orthopedic surgeons may experience challenges with lower limb treatment. Most previous reports have focused on EVC in childhood and few on its treatment in adulthood. Our patient was a 23-year-old woman with bilateral knee pain and gait abnormalities, with no history of orthopedic treatment. Valgus knee deformities with anterolateral depression of the lateral tibial plateaus and external rotation deformities of the lower legs were observed on radiography. We performed extra-articular osteotomy of the femurs and tibias and soft tissue release. Although the correction of each femur and tibia was good, mild valgus deformity of the lower limbs remained. This may be because the depression of the lateral tibial plateau was not repaired, and no postoperative remodeling was performed. However, 10 years post-surgery, no recurrence of the deformity was observed and walking was stable without pain. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COF) have been gathering much attention because the shapes, sizes, and chemical functions of their nanostructured pores can be arbitrarily controlled by designing the organic precursors. We fabricated cm-sized free-standing COF films with the thickness of 50–100 nm by an alternating vacuum deposition polymerization method. Precise adjustment of the stoichiometry by digitally controlled deposition was essential for producing the robust free-standing COF films. High-resolution electron microscopy revealed 3 nm pore structures, which correspond to the atomic structure of the COF. Small angle X-ray diffraction shows the existence of a similar periodicity. The CO2/N2 gas phase separation properties were evaluated from 103–105 Pa, and the parameters for each molecular permeation were determined. Based on the detailed analysis, it was found that the selectivity comes from the greater sorption affinity of CO2 to the COF compared to N2, which is consistent with the quantum chemical calculation. Since the vapor phase method can be used to coat various shaped templates, our method provides a new option for fabrication of neat COF membranes with various structures and their applications for the separation membrane. [ABSTRACT FROM AUTHOR]

Nucleic acids in body fluids, such as circulating cell-free nucleic acids, viral DNA, and RNA have received much attention for their great potential as biomarkers in liquid biopsies of serious diseases. Although quantitative polymerase chain reaction (qPCR) has been traditionally used as a laboratory-based assay for measuring nucleic acids, there is a strong demand for techniques to qualitatively, rapidly, and simply measure the extremely low-abundance nucleic acids in order to realize the nucleic acid-based liquid biopsies. With this aim in mind, we developed a simple and highly sensitive sandwich-type assay for nucleic acids using a combination of surface-enhanced Raman scattering (SERS), which enhances Raman scattering by 108– to 1010–fold, and bioorthogonal Raman tags, which generate signals in the biologically silent region (1800–2800 cm−1). Using gold nanorods having approximately 240 strands of oligonucleotides and 4-cyano-N-(2-mercaptoethyl)benzamide (4CMB) as the bioorthogonal Raman tag, we successfully detected target nucleic acids in a sequence-selective manner. [ABSTRACT FROM AUTHOR]

Tendons transmit force from muscle to bone for joint movement. Tenocytes are a specialized type of fibroblast that produces collagen fibrils in tendons. Their cytoplasmic processes form a network surrounding collagen fibrils to define a collagen fibre. Glycosaminoglycan (GAG) chains link collagen fibrils and adhere at the D‐band of the collagen fibril. In this study, we used array and scanning transmission electron microscope (STEM) tomographies to reconstruct the three‐dimensional ultrastructure of tenocytes, collagen fibres, collagen fibrils and GAG chains at the bifurcation of the bovine hindlimb superficial digital flexor tendon (SDFT). Collagen fibrils comprising a collagen fibre were not aligned uniformly and had at least two running directions. Spindle‐shaped tenocytes were arranged along the long axis of a plurality of collagen fibres, where two groups of collagen fibrils with oblique directions to each other exhibited an oblique overlap of the two collagen fibril layers. Collagen fibrils with different running directions were observed in separating layers of about 300 nm in thickness and had diameters of 0–200 nm. About 40% of all collagen fibrils had a peak in the range of 20–40 nm. STEM analysis of the same site where the crossing of collagen fibres was observed by transmission electron microscopy demonstrated the outline of collagen fibrils with a clear D‐banding pattern at a regular interval. Collagen fibrils were reconstructed three‐dimensionally using continuous images acquired by STEM tomography, which confirmed that the collagen fibrils at the crossing sites did not orientate in layers, but were woven one by one. Higher magnification observation of GAG chains attached between the crossing collagen fibrils revealed numerous GAG chains arranged either vertically or obliquely on collagen fibrils. Furthermore, GAG chains at the cross of collagen fibrils connected the closest D‐bands. GAG chains are thought to be universally present between collagen fibrils of the tendon. These observations by array and STEM tomographies increase our knowledge of the anatomy in the bifurcation of the bovine hindlimb SDFT and demonstrate the utility of these new imaging technologies. [ABSTRACT FROM AUTHOR]

TmFe2O4, a member of the RFe2O4 family (R = Sc, Y, In, and Dy to Lu), shows both charge and spin orderings and exhibits interesting dielectric and magnetic phenomena. We have grown epitaxial thin films of TmFe2O4 on (111)-oriented YSZ (yttria-stabilized zirconia) substrates via the pulsed laser deposition method and explored their interfacial structure at the atomic level and magnetic properties. The out-of-plane X-ray diffraction and reciprocal space mapping results reveal that the TmFe2O4 thin film grows with the c-axis perpendicular to the (111) surface of the YSZ substrate. The structure of the TmFe2O4/YSZ interface was investigated by using scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS). Interestingly, the hexagonal TmFeO3−δ phase has been found at the interface between the TmFe2O4 thin film and the YSZ substrate with the Tm3+-rich region at the upper side of the substrate. We suggest the possible growth mechanism based on the structural analysis. TmFe2O4 itself exhibits a spin or cluster glass transition, as verified by the fact that the external magnetic field dependence of irreversible transition temperature is described well in terms of the de Almeida–Thouless line and that the aging-memory effect is clearly observed. Furthermore, the field-cooled hysteresis loops and training effect clearly demonstrate the presence of the intrinsic exchange bias at 100 K due to the unique magnetic structure of the interface. [ABSTRACT FROM AUTHOR]