Stroke order normalization for improving recognition of online handwritten mathematical expressions

International Journal on Document Analysis and Recognition (IJDAR) - We present a technique based on stroke order normalization for improving recognition of online handwritten mathematical...     

Study on electrochemically deposited Mg metal

An electrodeposition process of magnesium metal from Grignard reagent based electrolyte was studied by comparing with lithium. The electrodeposition of magnesium was performed at various current densities. The obtained magnesium deposits did not show dendritic morphologies while all the lithium deposits showed dendritic products. Two different crystal growth modes in the electrodeposition process of magnesium metal were confirmed by an observation using scanning electron micro scope (SEM) and a crystallographic analysis using X-ray diffraction (XRD). An electrochemical study of the deposition/dissolution process of the magnesium showed a remarkable dependency of the overpotential of magnesium deposition on the electrolyte concentration compared with lithium. This result suggests that the dependency of the overpotential on the electrolyte concentration prevent the locally concentrated current resulting to form very uniform deposits.     

3D-Printed Methane-Producing Electrodes for Microbial Fuel Cells Developed Using Biogel Ink Containing Live Methanogens and White Charcoal

Methanogens are used as catalysts for cathodes in microbial fuel cells, to reduce CO₂ to CH₄. However, the attachment of microbes to the electrodes via culturing is time-consuming, and inadequate biofilm formation can lead to lesser surface area coverage, resulting in reduced methane formation. This study aims to improve the production efficiency and performance of methanogen cathodes developed using 3D printing of bioink containing live methanogens. A progressive cavity pump is used for the 3D gel-printing of methanogens and micro-sized white charcoal particles into the desired structure. Despite the absence of anaerobic conditions during printing, the 3D-printed cathodes with higher concentrations of microbial inoculum in the bioink produce more methane gas. Even with an unconcentrated inoculum, the methanogens multiply 800-fold during incubation, resulting in increased methane gas production. The predominant methanogens in the electrodes included the hydrogenotrophic Methanobacterium spp. Therefore, the technique used in this study can be used to successfully develop 3D-printed biocathodes catalyzed by methanogenic microbes with verifiable practical applicability. This study is the first to report the growth of methanogens and their methanogenic activity in 3D-printed cathodes.     

Effect of feeding astaxanthin with different E/Z-isomer ratios on astaxanthin accumulation in Pacific white shrimp Litopenaeus vannamei

Astaxanthin is traditionally utilized in crustacean aquaculture to enhance the characteristic pink-red color of these species. It has been reported that the bioavailability and body accumulation efficiency of astaxanthin differ based on its E/Z-isomer species, and these trends vary widely among animal species. This study investigated the influences of feeding astaxanthin having different E/Z-isomer proportions on astaxanthin accumulation in Pacific white shrimp Litopenaeus vannamei. Z-Isomer-rich astaxanthin was prepared from the synthetic (all-E)-astaxanthin standard by thermal treatment, and the prepared all-E-isomer-rich astaxanthin pellets (E-AST-P; total Z-isomer proportion = 4.7%) and Z-isomer-rich astaxanthin pellets (Z-AST-P; total Z-isomer proportion of astaxanthin = 81.8%) were fed to L. vannamei for 8 weeks. The feeding of Z-AST-P significantly improved the body astaxanthin concentration compared to those fed the control pellets without adding astaxanthin isomers and E-AST-P; the astaxanthin concentrations after the 8-week treatments of the control pellets, E-AST-P, and Z-AST-P were 7.3 ± 0.5, 6.2 ± 1.8, and 12.3 ± 1.3 µg g^–1, respectively. This result suggested that astaxanthin Z-isomers have higher bioavailability and/or body accumulation efficiency than (all-E)-astaxanthin in L. vannamei. Practical Applications: The bioavailability of astaxanthin is generally very low, which is a critical issue for its use in crustacean aquaculture. In this study, we found that feeding a pellet rich in astaxanthin Z-isomers showed a greater accumulation efficiency of astaxanthin in the whole body of L. vannamei than that fed a pellet rich in the all-E-isomer. Thus, the use of Z-isomer-rich astaxanthin feeds would contribute to improving the quality of crustacean and reducing the feed costs (i.e., reduction of the use amount of astaxanthin).     

Improvement of steady-state performance for discrete-valued input control with an integrator utilizing feedback control of integrated value of input

In this study, we considered the regulator problem for discrete-valued input control with an integrator. In some cases, the state does not converge to the origin in the discrete-valued input control when the plant possesses an integrator. Therefore, a method that adds minor feedback control to the integrated value of the input was proposed. However, the effect of the feedback control of the integrated value of the input was not theoretically interpreted, and the feedback gain for the state of the integrated value of the input was designed with trial and error. Herein, we clarify the effect of feedback control on the integrated value of the input. Furthermore, we reveal that the trade-off between the steady-state and transient performances is controlled by one parameter, that is, the feedback gain for the integrated value of the input.     

Gelatin Methacryloyl–Riboflavin (GelMA–RF) Hydrogels for Bone Regeneration

Gelatin methacryloyl (GelMA) is a versatile biomaterial that has been used in various biomedical fields. UV light is commonly used to photocrosslink such materials; however, its use has raised several biosafety concerns. We investigated the mechanical and biological properties of a visible-wavelength (VW)-light-crosslinked gelatin-based hydrogel to evaluate its viability as a scaffold for bone regeneration in bone-destructive disease treatment. Irgacure2959 or riboflavin was added as a photoinitiator to create GelMA solutions. GelMA solutions were poured into a mold and exposed to either UV or VW light. KUSA-A1 cell-laden GelMA hydrogels were crosslinked and then cultured. Mechanical characterization revealed that the stiffness range of GelMA–RF hydrogel was suitable for osteoblast differentiation. KUSA-A1 cells encapsulated in GelMA hydrogels photopolymerized with VW light displayed significantly higher cell viability than cells encapsulated in hydrogels photopolymerized with UV light. We also show that the expression of osteogenesis-related genes at a late stage of osteoblast differentiation in osteoblasts encapsulated in GelMA–RF hydrogel was markedly increased under osteoblast differentiation-inducing conditions. The GelMA–RF hydrogel served as an excellent scaffold for the encapsulation of osteoblasts. GelMA–RF hydrogel-encapsulated osteoblasts have the potential not only to help regenerate bone mass but also to treat complex bone defects associated with bone-destructive diseases such as periodontitis.     

Upregulation of Mineralocorticoid Receptor Contributes to Development of Salt-Sensitive Hypertension after Ischemia–Reperfusion Injury in Rats

The ischemia–reperfusion injury (IRI) of rat kidneys is used as a model of acute kidney injury. Salt-sensitive hypertension occurs in rats after IRI, and the distal nephrons play important roles in the development of this condition. We investigated the role of the mineralocorticoid receptor (MR) in the progression of IRI-induced salt-sensitive hypertension in rats. Fourteen days after right-side nephrectomy, IRI was induced by clamping the left renal artery, with sham surgery performed as a control. IRI rats were provided with normal water or water with 1.0% NaCl (IRI/NaCl), or they were implanted with an osmotic mini-pump to infuse vehicle or aldosterone (IRI/Aldo). Esaxerenone, a non-steroidal MR blocker (MRB), was administered to IRI/NaCl and IRI/Aldo rats for 6 weeks. MR expression increased by day 7 post-IRI. Blood pressure and urinary protein excretion increased in IRI/NaCl and IRI/Aldo rats over the 6-week period, but these effects were negated by MRB administration. The MRB attenuated the expression of the gamma-epithelial sodium channel (ENaC) and renal damage. The ENaC inhibitor, amiloride, ameliorated hypertension and renal damage in IRI/NaCl and IRI/Aldo rats. Our findings thus showed that MR upregulation may play a pivotal role in ENaC-mediated sodium uptake in rats after IRI, resulting in the development of salt-sensitive hypertension in response to salt overload or the activation of the renin–angiotensin–aldosterone system.     

Aerosolization of colloidal nanoparticles by a residual-free atomizer

Abstract

A new residual-free atomizer was designed to transfer colloidal nanoparticles measuring less than 100?nm into aerosol phase. Miniaturization of droplet size distribution successfully reduced background aerosol concentration of particles sized greater than 2.5?nm to 400 particles·mL^?1 of gas, which corresponded to an NaCl-equivalent impurity concentration of less than 100?ppb. Direct injection of colloid suspension enabled precise control of aerosol number concentrations by colloidal concentration (10⁵–10¹¹ particles·mL^?1 of liquid). Correlations between the size distributions of colloid and aerosol were also investigated using aqueous suspensions of the standard nanoparticles sized 10–100?nm. It was found that the aerosol size distribution was in very good agreement (i.e., less than 1?nm accuracy) with that measured by scanning electron microscopy.

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