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Employing the spin-wave formalism within and beyond the harmonic-oscillator approx-imation, we study the dynamic structure factors of spin-12 nearest-neighbor quantum Heisenberg antiferromagnets on two-dimensional quasiperiodic lattices with particular emphasis on a mag-netic analog to the well-known confined states of a hopping Hamiltonian for independent electrons on a two-dimensional Penrose lattice. We present comprehensive calculations on the C5v Penrose tiling in comparison with the C8v Ammann–Beenker tiling, revealing their decagonal and octagonal antiferromagnetic microstructures. Their dynamic spin structure factors both exhibit linear soft modes emergent at magnetic Bragg wavevectors and have nearly or fairly flat scattering bands, signifying magnetic excitations localized in some way, at several different energies in a self-similar manner. In particular, the lowest-lying highly flat mode is distinctive of the Penrose lattice, which is mediated by its unique antiferromagnons confined within tricoordinated sites only, unlike their itinerant electron counterparts involving pentacoordinated, as well as tricoordinated, sites. Bringing harmonic antiferromagnons into higher-order quantum interaction splits, the lowest-lying nearly flat scattering band in two, each mediated by further confined antiferromagnons, which is fully demonstrated and throughly visualized in the perpendicular as well as real spaces. We disclose superconfined antiferromagnons on the two-dimensional Penrose lattice.

We propose a new scheme of modifying spin waves so as to describe the thermodynamic properties of various noncollinear antiferromagnets with particular interest in a comparison between edge- versus corner-sharing triangular-based lattices. The well-known modified spin-wave theory for collinear antiferromagnets diagonalizes a bosonic Hamiltonian subject to the constraint that the total staggered magnetization be zero. Applying this scheme to frustrated noncollinear antiferromagnets ends in a poor thermodynamics, missing the optimal ground state and breaking the local U(1) rotational symmetry. We find such a plausible double-constraint condition for spin spirals as to spontaneously go back to the traditional single-constraint condition at the onset of a collinear Néel-ordered classical ground state. We first diagonalize only the bilinear terms in Holstein-Primakoff boson operators on the order of spin magnitude S and then bring these linear spin waves into interaction in a perturbative rather than variational manner. We demonstrate specific-heat calculations in terms of thus-modified interacting spin waves on various triangular-based lattices. In zero dimension, modified-spin-wave findings in comparison with finite-temperature Lanczos calculations turn out so successful as to reproduce the monomodal and bimodal specific-heat temperature profiles of the triangular-based edge-sharing Platonic and corner-sharing Archimedean polyhedral-lattice antiferromagnets, respectively. In two dimensions, high-temperature series expansions and tensor-network-based renormalization-group calculations are still controversial especially at low temperatures, and under such circumstances, modified spin waves interestingly predict that the specific heat of the kagome-lattice antiferromagnet in the corner-sharing geometry remains having both mid-temperature broad maximum and low-temperature narrow peak in the thermodynamic limit, while the specific heat of the triangular-lattice antiferromagnet in the edge-sharing geometry retains a low-temperature sharp peak followed by a mid-temperature weak anormaly in the thermodynamic limit. By further calculating one-magnon spectral functions in terms of our newly developed double-constraint modified spin-wave theory, we reveal that not only the elaborate modification scheme but also quantum corrections, especially those caused by the O ( S ^0 ) primary self-energies, are key ingredients in the successful description of triangular-based-lattice noncollinear antiferromagnets over the whole temperature range of absolute zero to infinity.

In this paper, we propose a pipeline that reproduces human skin mockups using a UV printer by obtaining the spatial concentration map of pigments from an RGB image of human skin. The pigment concentration distributions were obtained by a separating method of skin pigment components with independent component analysis from the skin image. This method can extract the concentration of melanin and hemoglobin components, which are the main pigments that make up skin tone. Based on this concentration, we developed a procedure to reproduce a skin mockup with a multi-layered structure that is determined by mapping the absorbance of melanin and hemoglobin to CMYK (Cyan, Magenta, Yellow, Black) subtractive color mixing. In our proposed method, the multi-layered structure with different pigments in each layer contributes greatly to the accurate reproduction of skin tones. We use a UV printer because the printer is capable of layered fabrication by using UV-curable inks. As the result, subjective evaluation showed that the artificial skin reproduced by our method has a more skin-like appearance than that produced using conventional printing.

In this paper, we proposed a method for matching the color and glossiness of an object between different displays by using tone mapping. Since displays have their own characteristics, such as maximum luminance and gamma characteristics, the color and glossiness of an object when displayed differs from one display to another. The color can be corrected by conventional color matching methods, but the glossiness, which greatly changes the impression of an object, needs to be corrected. Our practical challenge was to use tone mapping to correct the high-luminance part, also referred to as the glossy part, which cannot be fully corrected by color matching. Therefore, we performed color matching and tone mapping using high dynamic range images, which can record a wider range of luminance information as input. In addition, we varied the parameters of the tone-mapping function and the threshold at which the function was applied to study the effect on the object’s appearance. We conducted a subjective evaluation experiment using the series category method on glossy-corrected images generated by applying various functions to each display. As a result, we found that the differences in glossiness between displays could be corrected by selecting the optimal function for each display.

Worldwide, coral reef ecosystems are experiencing increasing pressure from a variety of anthropogenic perturbations including ocean warming and acidification, increased sedimentation, eutrophication, and overfishing, which could shift reefs to a condition of net calcium carbonate (CaCO3) dissolution and erosion. Herein, we determine the net calcification potential and the relative balance of net organic carbon metabolism (net community production; NCP) and net inorganic carbon metabolism (net community calcification; NCC) within 23 coral reef locations across the globe. In light of these results, we consider the suitability of using these two metrics developed from total alkalinity (TA) and dissolved inorganic carbon (DIC) measurements collected on different spatiotemporal scales to monitor coral reef biogeochemistry under anthropogenic change. All reefs in this study were net calcifying for the majority of observations as inferred from alkalinity depletion relative to offshore, although occasional observations of net dissolution occurred at most locations. However, reefs with lower net calcification potential (i.e., lower TA depletion) could shift towards net dissolution sooner than reefs with a higher potential. The percent influence of organic carbon fluxes on total changes in dissolved inorganic carbon (DIC) (i.e., NCP compared to the sum of NCP and NCC) ranged from 32% to 88% and reflected inherent biogeochemical differences between reefs. Reefs with the largest relative percentage of NCP experienced the largest variability in seawater pH for a given change in DIC, which is directly related to the reefs ability to elevate or suppress local pH relative to the open ocean. This work highlights the value of measuring coral reef carbonate chemistry when evaluating their susceptibility to ongoing global environmental change and offers a baseline from which to guide future conservation efforts aimed at preserving these valuable ecosystems.

Employing a two-orbital extended Peierls⁻Hubbard model, we demonstrate the photomanipulation of mixed-valent states in platinum-halide ladder compounds. There are two types of interchain valence arrangements, namely in-phase and out-of-phase types. The conversion of the in-phase structure to the out-of-phase structure is induced by photoirradiation, which is accelerated with increasing light intensity, while the reverse process hardly occurs. The out-of-phase arrangement is highly stabilized in the photoexcited states by the interchain electron transfer.

We introduce copper molybdenum cyanides of general formula Cu2[Mo(CN)8]·nH2O, which can serve as optofunctional magnetic devices. Their ground states generally stay paramagnetic down to temperatures of the K order but exhibit a spontaneous magnetization upon photoirradiation usually below a few tens of K. To interest us still further, such a ferromagnetic stateinduced by blue-laser irradiation is demagnetized step by step through further application of red or near-infrared laser pulses. We solve this intriguing photomagnetism. The ground-state properties are fully revealed by means of a group-theoretical technique. Taking account of experimental observations, we simulate applying pump laser pulses to a likely ground state and successfully reproduce both the magnetization and demagnetization dynamics. We monitor the photorelaxation process through angle-resolved photoemission spectroscopy. Electrons are fully itinerant in any of the photoinduced steady states, forming a striking contrast to the initial equilibrium state of atomic aspect. The fully demagnetized final steady state looks completely different from the initial paramagnetism but bears good analogy to one of the possible ground states available with the Coulomb repulsion on Cu sites suppressed.

A urea quantification method integrated with a pipette-tip-based biosensor and a smartphone was developed for the on-site diagnosis of blood urea nitrogen. When a sample solution containing phenol red is drawn into a pipette tip with urease immobilized on its inner wall, the color of the solution changes owing to an enzymatic reaction. The urea concentration can be quantified by photographing the pipette tip with a smartphone and quantifying the color intensity of the solution. In actual urea measurements, the detection limit (3σ) was estimated to be 1.3 mg/dL, indicating that the method has sufficient performance to quantify urea in serum. Furthermore, the method was found to reduce sample consumption and analysis time to 1/10 and 1/3, respectively, compared with conventional methods using microwell plates. This method requires only a micropipette and a smartphone to carry out measurements and does not require bench-top precision equipment or special training. Therefore, the method is expected to develop into a practical analytical platform for biomarker diagnostics that can be used in the field. [ABSTRACT FROM AUTHOR]

In this study, we developed an instrument-free visual pH determination method using a wedge-shaped microspace with pH-dependent swelling hydrogel particles. This method of pH measurement is achieved by utilizing the property of the hydrogel to swell with increasing pH and the wedge-shaped microspace in a 3D structure. Hydrogel particle formation using a microdroplet-forming chip and an ultraviolet LED enabled the fabrication of spherical pH-responsive hydrogel particles. Microchips with a wedge-shaped microspace of 500–3500 µm could be fabricated using the structures created by a photo-engineered 3D printer as templates. The evaluation of the method using a pH standard demonstrated that the settling distance of the particles decreased with increasing pH, and that the sensitivity and pH resolution were estimated to be 2.94 mm/pH and 0.2 pH, respectively. These results indicated that the method has the potential to visually measure pH. Furthermore, the developed method was applied to the determination of creatinine using creatinine deiminase. The method is readily applicable to biosensing technologies based on pH transduction, making it useful for on-site analysis in a wide range of fields, including medicine, environment, and food. Moreover, it can be adapted to microfluidic analysis for visual quantification using device-free micrototal analysis systems or lab-on-a-chip. [ABSTRACT FROM AUTHOR]

A portable multisample absorbance detection system for loop-mediated isothermal amplification using a positive temperature coefficient (PTC) heater was developed in this study. The system can simultaneously measure up to four samples and consists of four LEDs, four photodiodes, two PTC heaters, a sample holder, and a short-pass filter. The system successfully differentiated samples with and without human genomic DNA with photodiodes measuring absorbance in real time. We have also demonstrated that the quantitative analysis of human genomic DNA is possible at initial DNA concentrations ranging from 2.11 × 10² to 2.11 × 104 ng/µL. This device has potential use in on-site genetic testing owing to its compact size, portability, and capability to provide rapid results. [ABSTRACT FROM AUTHOR]

We developed a portable multi-fluorescence detection system for loop-mediated isothermal amplification (LAMP) using an indium tin oxide (ITO) transparent glass heater by improving a previously developed device. By changing the optical design and the material of the heating part, the quantitative performance and the stability of temperature control were improved. We demonstrated the basic performance of the developed device for genetic tests using LAMP by conducting discrimination tests for human genome DNA. We also showed that quantitative analysis of human genomic DNA is possible at initial DNA concentrations of 2.11 × 10²– 2.11 × 104 ng/µL using the developed device. This genetic testing device is smaller and lighter (60 × 90 × 70 mm³, 178 g) than conventional testing devices, giving it considerable potential to facilitate rapid and efficient on-site genetic testing. [ABSTRACT FROM AUTHOR]