Search

By illuminating matter with bright and intense light, researchers gain insights into material composition and properties. In the regime of extremely short wavelengths, X-ray free-electron lasers (XFELs) with exceptional peak brilliance have unveiled crucial details about the structures, dynamics and physics of various materials. Although X-ray focusing optics to enhance the intensity have progressed, achieving a single-nanometre focal spot that fully exploits the source performance remains elusive. Aberrations arising from reflective optical schemes noticeably degrade the focal spot, even in the presence of inevitably slight angular transition and pointing errors. Here we present an approach that directly forms a source image in an extremely small focal spot, achieving 7 nm focusing, in both transverse dimensions, of 9.1 keV XFELs with the extremely high intensity of 1.45 × 1022 W cm−2. This was made possible by a scheme combining concave and convex X-ray mirrors with suppressed aberrations and high angular tolerances. The attained highly intense X-rays, surpassing the previous intensity by a hundred-fold, induced the vigorous ionization of chromium, suggesting the creation of solid-density heavy bare atomic nuclei. Our results, which demonstrate the realization of stable ultraintense XFEL beams by forming demagnified source images, hold immediate significance to a wide range of research fields, including atomic, molecular and optical physics and high-energy-density sciences. Researchers focused hard X-rays from a free-electron laser down to transverse dimensions of ~7 nm × 7 nm, enabling a two-order increase in intensity of photons and yielding access to the elusive 1022 W cm−2 regime. Such intense, short-wavelength electromagnetic radiation may probe atomic, molecular and optical physics with extremely high resolution. [ABSTRACT FROM AUTHOR]

Purpose: Generalized anxiety disorder (GAD) is among the most prevalent and highly disabling mental health conditions that negatively impacts patient's quality of life (QOL) and disrupts activities of daily living. However, the recognition of GAD is difficult due to substantial overlap with other mental disorders. The purpose of this study was to estimate the prevalence of GAD, assess QOL of probable GAD patients in Japan, and gain insights on the status of visiting medical institutions as well as their recognition/awareness of the disorder. Patients and Methods: We conducted a web-based cross-sectional survey of 20,009 participants using a questionnaire with approximately 30 single/multiple choice or open-ended questions in Japanese. Results: Overall prevalence of GAD based on Generalized Anxiety Disorder 7-item (GAD-7) cutoff score of ≥ 10 and questionnaires developed with reference to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria was 7.6% (n=1530) and 6.0% (n=1197), respectively. The degree of coincidence between GAD diagnosis by DSM-5 criteria and GAD-7 scores was moderate (Cohen's Kappa=0.47, p< 0.01). Younger people reported a substantially higher prevalence of GAD compared to older. QOL scores assessed using EuroQol 5 dimensions 5-level and EuroQol Visual Analog Scale were substantially lower in probable GAD patients than those with GAD-7< 10. Anxiety/depression and pain/discomfort were the most prevalent issues and depression was the most reported comorbidity for the probable GAD patients. Probable GAD patients "currently visiting medical institutions" for anxiety or other mental issues were 27.6% (422/1530); a majority had seen specialists. Most of the probable GAD patients had never heard of the disease. Conclusion: We found higher prevalence of GAD and lower QOL of probable GAD patients in Japan. There is a need for creating awareness about GAD among the general population and developing clinical guidelines on GAD in Japan so that physicians can educate their patients. [ABSTRACT FROM AUTHOR]

A catalytically assisted etching method, named Catalyst-Referred Etching (CARE) was applied to the planarization of Lithium Niobate (LN) surface, which is widely used for optical waveguides, optical modulators, piezoelectric applications. The study demonstrates that an atomically smooth surface with less than 0.1 nm root-mean-square roughness could be achieved on a LN substrate using a thin metal film and pure water as the catalyst and etching solution, respectively. All residual stress and surface damage could be removed completely thanks to the removal mechanism of CARE.

During the 2021 excavation campaign carried out by the University of Tokyo in the so-called “Villa di Augusto” the excavation of a circular room (“Vano 23”) was completed. This building, probably connected to a large cistern (“Vano 15”) located nearby, had already been abandoned before the eruption of 472. It was filled with a stratigraphic sequence containing many archaeological materials, including a certain amount of marble slabs, probably belonging to an opus sectile decoration of one of the neighboring rooms. The analysis of the fragments of slabs gives us the opportunity to propose some observations on the type and chronology of the decorative apparatus and some further reflection on the qualitative level of the architectural complex. [ABSTRACT FROM AUTHOR]