Kidney stones have a high recurrence rate-10% within 5 years and 50% within 10. Crystalluria reflects the urinary physicochemical environment and may serve as a recurrence marker, but key crystals like brushite are rarely detected under ambient conditions. This study aimed to identify novel recurrence markers by inducing crystallization through urine cooling and analyzing crystal composition.
View Article and Find Full Text PDFKidney stone disease is a serious disease due to the severe pain it causes, high morbidity, and high recurrence rate. Notably, calcium oxalate stones are the most common type of kidney stone. Calcium oxalate appears in two forms in kidney stones: the stable phase, monohydrate (COM), and the metastable phase, dihydrate (COD).
View Article and Find Full Text PDFCalcium oxalate kidney stones, the most prevalent type of kidney stones, undergo a multi-step process of crystal nucleation, growth, aggregation, and secondary transition. The secondary transition has been rather overlooked, and thus, the effects on the disease and the underlying mechanism remain unclear. Here, we show, by periodic micro-CT images of human kidney stones in an ex vivo incubation experiment, that the growth of porous aggregates of calcium oxalate dihydrate (COD) crystals triggers the hardening of the kidney stones that causes difficulty in lithotripsy of kidney stone disease in the secondary transition.
View Article and Find Full Text PDFClimate change is increasing the frequency, intensity, and duration of extreme weather events across the globe. Understanding the capacity for ecological communities to withstand and recover from such events is critical. Typhoons are extreme weather events that are expected to broadly homogenize ecological dynamics through structural damage to vegetation and longer-term effects of salinization.
View Article and Find Full Text PDFSpatiotemporal control of the polymorphic phase transition of glycine crystals was demonstrated by three-dimensional (3D) processing with a focused femtosecond laser pulse as an external stimulus. We found that the transition from a metastable form (β-form) to more stable ones (α- or γ-form) could be triggered from the irradiated area of not only the surface but also inside of glycine crystals. This 3D processing with a focused femtosecond laser pulse enabled us to precisely monitor the transition dynamics from a targeted position to the entire part of crystals.
View Article and Find Full Text PDFThe development of electromagnetic wave absorbers operating in the sub-terahertz (sub-THz) region is necessary in 6G communications. We designed and fabricated a sub-THz metamaterial absorber based on metal microcoils embedded and periodically arranged in a dielectric substrate. The microcoil parameters were optimized by calculating the electromagnetic response of the metamaterial using finite element analysis.
View Article and Find Full Text PDFConcerns about widespread human-induced declines in insect populations are mounting, yet little is known about how land-use change modifies both the trends and variability of insect communities, particularly in understudied regions. Here, we examine how the seasonal activity patterns of ants-key drivers of terrestrial ecosystem functioning-vary with anthropogenic land-cover change on a subtropical island landscape, and whether differences in temperature or species composition can explain observed patterns. Using trap captures sampled biweekly over 2 years from a biodiversity monitoring network covering Okinawa Island, Japan, we processed 1.
View Article and Find Full Text PDFWe report the generation of picosecond pulsed light at a 266 nm wavelength with an average power of 53 W. We developed a picosecond pulsed 1064 nm laser source with an average power of 261 W, a repetition rate of 1 MHz, and a pulse duration of 14 ps, using a gain-switched DFB laser diode as a seed laser and a 914 nm laser-diode-pumped Nd-doped YVO power amplifier. We achieved stable generation of 266 nm light with an average power of 53 W from frequency quadrupling using an LBO and a CLBO crystals.
View Article and Find Full Text PDFFocused irradiation with ultrashort laser pulses realized the fine spatiotemporal control of ice crystallization in supercooled water. An effective multiphoton excitation at the laser focus generated shockwaves and bubbles, which acted as an impulse for inducing ice crystal nucleation. The impulse that was localized close to the laser focus and accompanied by a small temperature elevation allowed the precise position control of ice crystallization and its observation with spatiotemporal resolution of micrometers and microseconds using a microscope.
View Article and Find Full Text PDFWe sought to identify and quantitatively analyze calcium oxalate (CaOx) kidney stones on the order of micrometers, with a focus on the quantitative identification of calcium oxalate monohydrate (COM) and dihydrate (COD). We performed Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), and microfocus X-ray computed tomography measurements (microfocus X-ray CT) and compared their results. An extended analysis of the FTIR spectrum focusing on the 780 cm-1 peak made it possible to achieve a reliable analysis of the COM/COD ratio.
View Article and Find Full Text PDFA unique design of our ultracompact microcavity wavelength conversion device exploits the simple principle that the wavelength conversion efficiency is proportional to the square of the electric field amplitude of enhanced pump light in the microcavity, and expands the range of suitable device materials to include crystals that do not exhibit birefringence or ferroelectricity. Here, as a first step toward practical applications of all-solid-state ultracompact deep-ultraviolet coherent light sources, we adopted a low-birefringence paraelectric SrBO crystal with great potential for wavelength conversion and high transparency down to 130 nm as our device material, and demonstrated 234 nm deep-ultraviolet coherent light generation, whose wavelength band is expected to be used for on-demand disinfection tools that can irradiate the human body.
View Article and Find Full Text PDFIslands make up a large proportion of Earth's biodiversity, yet are also some of the most sensitive systems to environmental perturbation. Biogeographic theory predicts that geologic age, area, and isolation typically drive islands' diversity patterns, and thus potentially impact non-native spread and community homogenization across island systems. One limitation in testing such predictions has been the difficulty of performing comprehensive inventories of island biotas and distinguishing native from introduced taxa.
View Article and Find Full Text PDFOpt Express
March 2022
We report 10,000-hour stable operation of a 266-nm picosecond laser with an average power of 20 W. We have developed a narrow-linewidth, high-peak-power 1064-nm laser source with a repetition rate of 600 kHz, an average power of 129 W, a linewidth of 0.15 nm, and a pulse duration of 14 ps using a gain-switched DFB-LD as a picosecond pulse seed source and a four-stage power amplifier with an Nd:YVO crystal.
View Article and Find Full Text PDFGallium nitride (GaN) is one of the most technologically important semiconductors and a fundamental component in many optoelectronic and power devices. Low-resistivity GaN wafers are in demand and actively being developed to improve the performance of vertical GaN power devices necessary for high-voltage and high-frequency applications. For the development of GaN devices, nondestructive characterization of electrical properties particularly for carrier densities in the order of 10 cm or higher is highly favorable.
View Article and Find Full Text PDFThe pathogenesis of kidney stone formation includes multi-step processes involving complex interactions between mineral components and protein matrix. Calcium-binding proteins in kidney stones have great influences on the stone formation. The spatial distributions of these proteins in kidney stones are essential for evaluating the in vivo effects of proteins on the stone formation, although the actual distribution of these proteins is still unclear.
View Article and Find Full Text PDFUnder 266-nm (deep ultraviolet, DUV) laser irradiation, an SrBO (SBO) single crystal has been found to exhibit a surface laser-induced damage threshold (LIDT) of ∼ 16.4 J/cm, which is higher than those of a synthetic silica glass (4.8 J/cm) and a calcium fluoride (CaF) crystal (11.
View Article and Find Full Text PDFEng Life Sci
September 2020
It is known that interfaces have various impacts on crystallization from a solution. Here, we describe crystallization of acetaminophen using a microflow channel, in which two liquids meet and form a liquid-liquid interface due to laminar flow, resulting in uniform mixing of solvents on the molecular scale. In the anti-solvent method, the microflow mixing promoted the crystallization more than bulk mixing.
View Article and Find Full Text PDFNucleolin (NCL) is a nucleolar protein i.e. involved in the regulation of the nucleolar structure and functions, and consists of three distinct regions: the N-terminal region; the middle region, which contains four RNA-recognition motifs (RRMs); and the C-terminal glycine- and arginine-rich (GAR) region.
View Article and Find Full Text PDFWe report the generation of a 266 nm deep ultraviolet (DUV) picosecond pulse with an average output power of 14 W by the fourth-harmonic generation (FHG) from two consecutive frequency-doubling stages of a 1064 nm pulse based on a gain-switched-laser-diode (LD)-seeded hybrid fiber/solid-state master oscillator and power amplifier (MOPA) system. Through the gain-switched operation of a narrow-spectral-linewidth distributed-feedback laser diode and by using a Yb-doped fiber and a two-stage ${\rm Nd}:{{\rm YVO}_4}$Nd:YVO solid-state amplifier, we achieved an average power of 46.5 W near the Fourier transform limit for a 13 ps pulse with a repetition rate of 200 kHz.
View Article and Find Full Text PDFDeposition of islet amyloid consisting of amylin constitutes one of pathological hallmarks of type 2 diabetes mellitus (T2DM), and it may be involved in the development and progression of T2DM. However, the details about the relationship between the deposition of islet amyloid and the pathology of T2DM remain unclear, since no useful imaging tracer enabling the visualization of pancreatic amylin is available. In the present study, we synthesized and evaluated six novel F-labeled phenoxymethylpyridine (PMP) derivatives as amylin imaging probes.
View Article and Find Full Text PDFIt is generally accepted that neurofibrillary tangles consisting of tau proteins are involved in the pathogenesis of Alzheimer's disease (AD). For selective detection of tau pathology, we synthesized and evaluated radioiodinated benzoimidazopyridine (BIP) derivatives with an alkylamino group as tau imaging probes. selectivity to tau aggregates and pharmacokinetics of BIP derivatives varied markedly, being strongly dependent on the alkylamino group.
View Article and Find Full Text PDFSubstantial enhancement of terahertz magnetic near field achieved by the combination of a tapered metallic waveguide and a micro-split-ring resonator is demonstrated. The magnetic near field is probed directly via the magneto-optic sampling with a TbGaO crystal. The incident terahertz wave with a half-cycle waveform is generated by using the pulse-front tilting method.
View Article and Find Full Text PDFSoft x-ray microscopy (SXM) is a minimally invasive technique for single-cell high-resolution imaging as well as the visualization of intracellular distributions of light elements such as carbon, nitrogen, and oxygen. We used SXM to observe photosynthesis and nitrogen fixation in the filamentous cyanobacterium sp. PCC 7120, which can form heterocysts during nitrogen starvation.
View Article and Find Full Text PDFDevelopment of new diagnostic imaging probes for Alzheimer's disease, such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) probes, has been strongly desired. In this study, we investigated the most accessible amyloid β (Aβ) binding site of [I]IMPY, a Thioflavin-T-derived SPECT probe, using experimental and computational methods. First, we performed a competitive inhibition assay with Orange-G, which recognizes the KLVFFA region in Aβ fibrils, suggesting that IMPY and Orange-G bind to different sites in Aβ fibrils.
View Article and Find Full Text PDFIn molecular imaging research, the development of multimodal imaging probes has recently attracted much attention. In the present study, we prepared radioiodinated BODIPY and applied it as a nuclear and optical dual functional labeling agent for proteins and peptides. We designed and synthesized [I]BODIPY with a N-hydroxysuccinimide (NHS) ester, and evaluated its utility as a nuclear and fluorescent dual labeling agent for proteins and peptides.
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