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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]

In this paper, we propose a method of image conversion that changes unglossy images into glossy ones using deep photo style transfer. This style of transfer is expected to reproduce the desired image with a metallic appearance based on the technique used for texture transfer. A practical challenge was undertaken to create a gold, metallic image by transferring the style images of a gold ingot. To avoid excessive loss of color balance, we applied the YCrCb separation technique and used only the Y component to reproduce a glossy appearance. The luminance and saturation of the style image were altered to investigate the influence on the convergence of appearance because the converted images should be dependent on the contents of the images. The results of transfer were assessed by subjective evaluation using the semantic differential method. A style image with an appropriate amount of change in contrast was found suitable for an appropriate glossy appearance. Moreover, contrast in the style image can be appropriately chosen depending on the contents of the original images. [ABSTRACT FROM AUTHOR]

Carbon captured by marine living organisms is called "blue carbon", and seagrass meadows are a dominant blue carbon sink. However, our knowledge of how seagrass increases sedimentary organic carbon (OC) stocks is limited. We investigated two pathways of OC enrichment: trapping of organic matter in the water column and the direct supply of belowground seagrass detritus. We developed a new type of box corer to facilitate the retrieval of intact cores that preserve the structures of both sediments (including coarse sediments and dead plant structures) and live seagrass bodies. We measured seagrass density, total OC mass (OCtotal) [= live seagrass OC biomass (OCbio) + sedimentary OC mass (OCsed)], and the stable carbon isotope ratio (δ13C) of OCsed at back-reef and estuarine sites in the tropical Indo-Pacific region. OCbio accounted for 19 % and OCsed for 81 % of OCtotal; this contribution of OCbio to OCtotal is the highest in globally compiled data. Belowground detritus accounted for ~ 90 % of the OC mass of dead plant structures (> 2 mm in size) (OCdead). At the back-reef site, belowground seagrass biomass, OCdead, and δ13C of OCsed (δ13Csed) were positively correlated with OCsed, indicating that the direct supply of belowground seagrass detritus is a major mechanism of OCsed enrichment. At the estuarine site, aboveground seagrass biomass was positively correlated with OCsed but δ13Csed did not correlate with OCsed, indicating that trapping of suspended OC by seagrass leaves is a major mechanism of OCsed enrichment there. We inferred that the relative importance of these two pathways may depend on the supply (productivity) of belowground biomass. Our results indicate that belowground biomass productivity of seagrass meadows, in addition to their aboveground morphological complexity, is an important factor controlling their OC stock. Consideration of this factor will improve global blue-carbon estimates. [ABSTRACT FROM AUTHOR]

We propose a new scheme for modifying conventional spin waves so as to precisely describe low-dimensional Heisenberg ferrimagnets at finite temperatures. What is called the modified spin-wave theory was initiated by Takahashi, who intended to calculate the low-temperature thermodynamics of low-dimensional Heisenberg ferromagnets, where Holstein–Primakoff bosons are constrained to keep the total uniform magnetization zero in a straightforward manner. If the concept of an ideal Bose gas with a fixed density is applied to antiferromagnets and ferrimagnets, the formulation is no longer trivial, having rich variety in the way how the conventional spin waves, especially those in ferrimagnets, are constrained and brought into interaction. Which magnetization should be kept zero, uniform, staggered, or both? One or more chemical potentials can be introduced so as to satisfy the relevant constraint condition either in diagonalizing the Hamiltonian or in minimizing the free energy, making the Bogoliubov transformation dependent on temperature or leaving it free from temperature dependence. We can bring the thus-modified spin waves into interaction on the basis of the Hartree–Fock approximation or through the use of Wick’s theorem in an attempt to refine their descriptions. Comparing various modification schemes both numerically and analytically in one and two dimensions, we eventually find an excellent bosonic language capable of describing heterogeneous quantum magnets on a variety of lattices over the whole temperature range—Wick’s-theorem-based interacting spin waves modified so as to keep every sublattice magnetization zero via the temperature-dependent Bogoliubov transformation. [ABSTRACT FROM AUTHOR]

Background: Vancomycin (VCM) requires dose adjustment based on therapeutic drug monitoring. At Aomori Prefectural Central Hospital, physicians carried out VCM therapeutic drug monitoring based on their experience, because pharmacists did not participate in the dose adjustment. We evaluated the impact of an Antimicrobial Stewardship Program (ASP) on attaining target VCM trough concentrations and pharmacokinetics (PK)/pharmacodynamics (PD) parameters in patients with methicillin-resistant Staphylococcus aureus (MRSA) infections. Materials and methods: The ASP was introduced in April 2012. We implemented a prospective audit of prescribed VCM dosages and provided feedback based on measured VCM trough concentrations. In a retrospective pre- and postcomparison study from April 2007 to December 2011 (preimplementation) and from April 2012 to December 2014 (postimplementation), 79 patients were treated for MRSA infection with VCM, and trough concentrations were monitored (pre, n=28; post, n=51). In 65 patients (pre, n=15; post, n=50), 24-hour area under the concentration--time curve (AUC 0-24 h)/minimum inhibitory concentration (MIC) ratios were calculated. Results: Pharmacist feedback, which included recommendations for changing dose or using alternative anti-MRSA antibiotics, was highly accepted during postimplementation (88%, 29/33). The number of patients with serum VCM concentrations within the therapeutic range (10-20 mg/mL) was significantly higher during postimplementation (84%, 43/51) than during preimplementation (39%, 11/28) (P<0.01). The percentage of patients who attained target PK/ PD parameters (AUC 0-24 h/MIC >400) was significantly higher during postimplementation (84%, 42/50) than during preimplementation (53%, 8/15; P=0.013). There were no significant differences in nephrotoxicity or mortality rate. Conclusion: Our ASP increased the percentage of patients that attained optimal VCM trough concentrations and PK/PD parameters, which contributed to the appropriate use of VCM in patients with MRSA infections. [ABSTRACT FROM AUTHOR]

We study photoinduced phase transitions in linear homocyclic and heterocyclic aromatic polymers, numerically solving the time-dependent Schrödinger equation and observing the photoinduced optical conductivity spectra along the way. All the polycyclic compounds of our interest have bistable cis-trans isomers, which are degenerate in energetics but distinct in optics, and therefore exhibit corresponding photochromism. We reveal that the molecular symmetry is decisive of the photoexchangeability of these bistable configurations, which is directional in molecules of the D2h geometry such as polyacene and paracyanogen but is bidirectional in those of the C2v geometry such as polypyridinopyridine and B, N-substituted acenes. We propose a series of polycyclic compounds for designing tunable photochromism of geometric origin. [ABSTRACT FROM AUTHOR]

We introduce copper molybdenum cyanides of general formula Cu2[Mo(CN)8].nH2O, which can serve as optofunctionalmagnetic 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. [ABSTRACT FROM AUTHOR]