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In this study, a single zirconium carbide (ZrC) nanoneedle structure oriented in the <100> direction was fabricated by a dual-beam focused ion beam (FIB-SEM) system, and its field emission characteristics and emission current stability were evaluated. Benefiting from controlled fabrication with real-time observation, the ZrC nanoneedle has a smooth surface and a tip with a radius of curvature smaller than 20 nm and a length greater than 2 μm. Due to its low work function and well-controlled morphology, the ZrC nanoneedle emitter, positioned in a high-vacuum chamber, was able to generate a single and collimated electron beam with a current of 1.2 nA at a turn-on voltage of 210 V, and the current increased to 100 nA when the applied voltage reached 325 V. After the treatment of the nanoneedle tip, the field emission exhibited a stable emission for 150 min with a fluctuation of 1.4% and an emission current density as high as 1.4 × 1010 A m−2. This work presents an efficient and controllable method for fabricating nanostructures, and this method is applicable to the transition metal compound ZrC as a field emission emitter, demonstrating its potential as an electron source for electron-beam devices. [ABSTRACT FROM AUTHOR]

Introduction Cytoplasmic male sterility (CMS) is a phenomenon in which plants fail to produce fertile pollen due to a mitochondrial gene. The phenotypic expression of CMS is suppressed by the [...], The mitochondrial gene orf108, which is co-transcribed with atp1 and causes cytoplasmic male sterility in Brassica crops, is widely distributed across wild species and genera of Brassicaceae. However, to date, intraspecific variations in the presence of orf108 have not yet been studied, and the mechanisms underlying the wide distribution of the gene remain unclear. We analyzed the presence and sequence variations of orf108 in two wild species, Brassica maurorum and Moricandia arvensis. After polymerase chain reaction amplification of the 5 (0) region of atp1 and the coding sequence of orf108, we determined the DNA sequences. Brassica maurorum and M. arvensis showed variations in the presence of orf108 or orf117 (orf108 (V117)) both between and within accessions and were not fixed to the mitochondrial type with the male sterile genes. Sequencing of the amplicons showed that B. maurorum had orf108 (V117) instead of orf108. Sequencing also indicated mitochondrial heteroplasmy in the two species; in particular, in B. maurorum, one plant possessed both orf108 and orf108 (V117) sequences. These results suggest that substoichiometric shifting of mitochondrial genomes leads to the acquisition or loss of orf108. Furthermore, fertility restorer genes of the two species were involved in the processing of the mRNA of male sterility genes at different sites. Key words: orf108, orf117, intraspecific variation, Brassica maurorum, Moricandia arvensis. Le gene mitochondrial orf108, lequel est co-transcrit avec atp1 et cause l&apos;androsterilite cytoplasmique chez les Brassica cultives, est largement distribue au sein des especes sauvages et divers genres chez les cruciferes. Cependant, a ce jour, aucune etude de la variation intraspecifique quant a la presence de l&apos;orf108 n&apos;a ete realisee et les mecanismes assurant une large distribution de ce gene restent inconnus. Les auteurs ont examine la presence et les variations dans la sequence de l&apos;orf108 chez deux especes sauvages, Brassica maurorum et Moricandia arvensis. Apres amplification PCR de la region 5 (0) du gene atp1 et des sequences codantes de l&apos;orf108, les auteurs en ont realise le sequencage. Au sein de B. maurorum et de M. arvensis, de la variation a ete observee pour la presence des orf108 et orf117 (orf108 (V117)) tant entre les accessions qu&apos;au sein de celles-ci et ces variations n&apos;etaient pas fonction de la presence des genes de sterilite. Le sequencage des amplicons a permis d&apos;etablir que le B. maurorum possede l&apos;orf108 (V117) plutot que l&apos;orf108. Le sequencage a aussi revele une heteroplasmie mitochondriale chez ces deux especes, en particulier chez le B. maurorum ou une plante possedait les deux sequences (orf108 et orf108 (V117)). Ces resultats suggerent que des changements substoichiometriques dans les genomes mitochondriaux menent a l&apos;acquisition ou a la perte de l&apos;orf108. De plus, les genes de restauration de la fertilite chez les deux especes etaient impliques dans la maturation de l&apos;ARNm des genes d&apos;androsterilite a differents sites. Mots-cles : orf108, orf117, variation intraspecifique, Brassica maurorum, Moricandia arvensis.

A syngas was generated at a near-unity H2/CO ratio independent of the reactant gas composition over Rh-loaded strontium titanate in the photo-induced dry reforming of methane. Moreover, light irradiation inhibited side reactions, such as the reverse water gas shift reaction and the precipitation of the solid-state carbon. These results were not explained by thermodynamic equilibrium, but were presumably owing to the unique effect of the photogenerated electron–hole pairs. [ABSTRACT FROM AUTHOR]

Persistent homology is a powerful tool for quantifying various structures, but it is equally crucial to maintain its interpretability. In this study, we extracted interpretable geometric features from the persistent diagrams (PDs) of scanning transmission electron microscopy (STEM) images of self-assembled Pt-CeO2 nanostructures synthesized under different annealing conditions. We focused on PD quadrants and extracted five interpretable features from the zeroth and first PDs of nanostructures ranging from maze-like to striped patterns. A combination of hierarchical clustering and inverse analysis of PDs reconstructed by principal component analysis through vectorization of the PDs highlighted the importance of the number of arc-like structures of the CeO2 phase in the first PDs, particularly those that were smaller than a characteristic size. This descriptor enabled us to quantify the degree of disorder, namely the density of bends, in nanostructures formed under different conditions. By using this descriptor along with the width of the CeO2 phase, we classified 12 Pt-CeO2 nanostructures in an interpretable way. [ABSTRACT FROM AUTHOR]

Ever since Stephen Paget's 1889 hypothesis, metastatic organotropism has remained one of cancer's greatest mysteries. Here we demonstrate that exosomes from mouse and human lung-, liver- and brain-tropic tumour cells fuse preferentially with resident cells at their predicted destination, namely lung fibroblasts and epithelial cells, liver Kupffer cells and brain endothelial cells. We show that tumour-derived exosomes uptaken by organ-specific cells prepare the pre-metastatic niche. Treatment with exosomes from lung-tropic models redirected the metastasis of bone-tropic tumour cells. Exosome proteomics revealed distinct integrin expression patterns, in which the exosomal integrins α6β4 and α6β1 were associated with lung metastasis, while exosomal integrin αvβ5 was linked to liver metastasis. Targeting the integrins α6β4 and αvβ5 decreased exosome uptake, as well as lung and liver metastasis, respectively. We demonstrate that exosome integrin uptake by resident cells activates Src phosphorylation and pro-inflammatory S100 gene expression. Finally, our clinical data indicate that exosomal integrins could be used to predict organ-specific metastasis.

Graphene–graphene oxide (GO) hybrid liquid cells (LCs) for liquid-phase scanning transmission electron microscopy (STEM) were fabricated using a facile method with commercial graphene on a polymethyl methacrylate sheet and GO on a TEM grid. LCs containing Pt nanoparticles (NPs) and pure water were efficiently produced and observed via STEM. Their composition and thickness were characterized by STEM-electron energy-loss spectroscopy. High-resolution (HR) STEM revealed slow-moving Pt NPs' atomic structures and fast-moving single Pt atoms at the LC's thin edges. Minimal damage during HR STEM indicated stable LCs because of their excellent electrical and thermal conductivities and radiolysis species scavenging ability. [ABSTRACT FROM AUTHOR]

Aim: We aimed to investigate the associations of endometriosis and adenomyosis with pregnancy complications by using a large‐scale Japanese database. Methods: We retrospectively analyzed 145 590 singleton pregnancies from the Japan Perinatal Registry Network Database. Pregnant women registered as having endometriosis or adenomyosis were designated as the case group (EA), whereas the control group (non‐EA) was selected using propensity‐score matching adjusted for variables such as age, parity, BMI, smoking history, and the use of assisted reproductive technology. The main outcomes included placental malposition, preterm birth, and hypertensive disorders of pregnancy (HDP). Results: In total, 1203 patients from both the EA and non‐EA groups were matched and evaluated. The EA group showed significantly higher rates of placenta previa (odds ratio [OR], 3.01; 95% confidence interval [CI], 1.84–4.92), low‐lying placenta (OR, 2.02; 95% CI, 1.06–3.86), and preterm birth (OR, 1.44; 95% CI, 1.13–1.84) than the non‐EA group. However, no significant difference was observed in the incidence of HDP (OR, 1.22; 95% CI, 0.90–1.66). Conclusion: The use of propensity‐score matching to analyze a nationwide perinatal database in Japan clarified that EA was associated with increased pregnancy complications, specifically placental malposition, including placenta previa and low‐lying placenta, and preterm birth, but not with HDP. [ABSTRACT FROM AUTHOR]

Adenomyosis is associated with unfavorable perinatal outcomes, and recent case reports show that some women with adenomyosis experience pain at the adenomyosis lesion during pregnancy and have detrimental perinatal outcomes. This study aimed to clarify the clinical characteristics of this pain and perinatal outcomes associated with this phenomenon. This was a single-center retrospective analysis of pregnant women with adenomyosis. The incidence of pain onset at adenomyosis lesions, defined as persistent pain at the adenomyosis site with administration of analgesics for pain relief, and its association with perinatal outcomes were analyzed. Among 91 singleton pregnancies with adenomyosis, 12 pregnancies (13.2 %) presented with pain. One pregnancy resulted in second-trimester miscarriage, and 5 of the 11 pregnancies (45 %) developed preeclampsia, which resulted in preterm delivery, and 3 of the 12 pregnancies (25 %) achieved term delivery. The incidence of preeclampsia and preterm delivery was higher in those who experienced pain than in those without (45 % [5/11] vs. 15 % [11/74]; p<0.05, and 73 % [8/11] vs. 34 % [25/74]; p<0.05, respectively). Among women with pain, the maximum C-reactive protein level was significantly higher in women who developed preeclampsia than in those who did not (5.45 vs. 0.12 mg/dL, p<0.05). Our study revealed that adenomyosis can cause pain in over one of eight pregnancies with adenomyosis, which may be associated with the increased incidence of preeclampsia resulting in preterm delivery. Women with pain, especially those with high C-reactive protein levels, may be at high risk for future development of preeclampsia and consequent preterm delivery. [ABSTRACT FROM AUTHOR]