Self-Assembly of Elastin–Mimetic Double Hydrophobic Polypeptides

We have constructed a novel class of “double-hydrophobic” block polypeptides based on the hydrophobic domains found in native elastin, an extracellular matrix protein responsible for the elasticity and resilience of tissues. The block polypeptides comprise proline-rich poly(VPGXG) and glycine-rich poly(VGGVG), both of which dehydrate at higher temperature but form distinct secondary structures, β-turn and β-sheet respectively. In water at 45 °C, the block polypeptides initially assemble into nanoparticles rich in β-turn structures, which further connect into long (>10 μm), beaded nanofibers along with the increase in the β-sheet content. The nanofibers obtained are well-dispersed in water, and show thermoresponsive properties. Polypeptides comprising each block component assemble into different morphologies, showing that the conjugation of poly(VPGXG) and poly(VGGVG) plays a role for beaded fiber formation. These results may provide innovative ideas for designing peptide-based materials but also opportunities for developing novel materials useful for tissue engineering and drug delivery systems

Behavior of Oxide-layer Adhered on Tool Surface when Machining Ca-Deoxidized Steel

Machining of Ca-Si deoxidized, Fe-Si deoxidized and conventionally deoxidized steels was investigated in order to reveal the effect and mechanism of the tool surface layer consistnig of oxides and sulfides in preventing tool wear. The tool surface layers were surveyed by the electron probe X-ray micro-analyzer, and the structural components of the layer were identified in this study. The following concludions were obtained : When machining Ca-Si deoxidized or Fe-Si deoxidized steels, the oxides and sulfides form layers on the tool surface, which avoid the direct contact of the work iron with the tool carbides, prevent the diffusion of the tool material. When cutting Ca-Si deoxidized steels, a semitransparent layer forms preferably on carbide tools which contain TiC, and it consists of 2 to 3 CaO-Al₂O₃-SiO₂. In the case of Fe-Si deoxidized steels, an ashy-grey coloured layer forms preferably on ceramic tools and it consists of CaO, Al₂O₃, SiO₂ and MnS

Observing Depolymerization of a RAFT Polymer by Time-Resolved Small-Angle X ray Scattering

Takahashi R., Sugawara-Narutaki A.. Observing Depolymerization of a RAFT Polymer by Time-Resolved Small-Angle X ray Scattering. ACS Polymers Au 5, 129 (2025); https://doi.org/10.1021/acspolymersau.4c00095.Recently, it has been reported that various polymethacrylates synthesized via reversible addition-fragmentation chain-transfer (RAFT) polymerization may be depolymerized by heating them to 120 °C in solution. However, insights into the mechanisms and kinetics remain limited. In this work, we monitored the depolymerization process of poly(benzyl methacrylate) in p-xylene using time-resolved small-angle X-ray scattering (SAXS). The results revealed that the weight-average molecular weight gradually decreased, while the z-average radius of gyration remained almost unchanged until approximately half of the repeating units were converted. This unexpected behavior could be well-reproduced by a kinetic model of end-to-end depolymerization (unzipping). This study provides the first direct observation of the structural evolution during depolymerization via an unzipping mechanism

Polymerization-induced self-assembly enables access to diverse highly ordered structures through kinetic and thermodynamic pathways

Shibata I., Sugawara-Narutaki A., Takahashi R.. Polymerization-induced self-assembly enables access to diverse highly ordered structures through kinetic and thermodynamic pathways. Chemical Science 16, 7921 (2025); https://doi.org/10.1039/D5SC01703C.Polymerization-induced self-assembly (PISA) has emerged as a powerful technique for generating microphase-separated structures, but research has primarily focused on systems exhibiting “disordered” structures. Here, we demonstrate the facile construction of various highly ordered microphase-separated structures via PISA, with and without kinetic control through manipulation of the glass transition temperature (Tg) of the core-forming blocks. We synthesized diblock copolymers in an ionic liquid (40 wt% solute) by polymerizing styrene or 2-hydroxyethyl acrylate from one end of poly(ethylene glycol). When using polystyrene as the core-forming block, its high Tg relative to the polymerization temperature resulted in the formation of kinetically trapped structures, including pure hexagonal close-packed (HCP) spheres exhibiting X-ray diffraction peaks up to the 17th-order. Conversely, lower-Tg core-forming block [poly(2-hydroxyethyl acrylate)] led to thermodynamically stable, highly ordered structures, including a double-gyroid morphology. These results highlight the efficacy of PISA for generating diverse, highly ordered microphase-separated structures from simple diblock copolymers and demonstrate its potential to access structures unattainable through conventional ex situ polymerization

Influence of Process Parameters in n-PMEDM of Inconel 800 with Electrode and Coated Electrodes

By considering the unique performances, the Powder Mixed Electrical Discharge Machining (PMEDM) mostly encounter choice for machining the hard materials with job features like intricate shapes with grater accuracy and those materials are difficult to cut in conventional machining processes. This Research aimed to prepare parameter index chart for machining nickel based super alloy - Inconel 800 for various requirements. To achieve the aim, In this experimental study on machining of Inconel 800 in PMEDM with electrolyte copper electrode as well as silver coated electrolyte copper electrode is focused. Taguchi full factorial design derived from MINITAB release-16 software was used to design the experimentation. The factors like pulse off time, Current and Pulse on Time were considered. The responses like amount of Tool Wear, Quantity of material removal, surface finishes were noted against each case. In the same experimental conditions the coated electrode increased the MRR by 36.67% with minor increment of maximum surface roughness to 16.11%

The Administration of Xultophy for Diabetic Patients on Hemodialysis

Background: Recent diabetic treatments include Insulin Degludec/ liraglutide (IDeg/Lira, Xultophy) in clinical practice. Authors have continued clinical research concerning diabetes, chronic renal failure, dialysis, and others. Subjects and Methods: Ten patients with type 2 diabetes mellitus (T2DM) undergoing hemodialysis were investigated. They showed that ages 74.5 ± 5.9 years, M/F=6/4, BMI 21.1± 3.8kg/m2, hemodialysis duration 8.1 ± 5.7 years. At the beginning, fundamental data were Cre 8.2 ± 1.9 mg/dL, HbA1c 6.5 ± 0.8%. Xultophy was started on 5-12 doses and continued for 6 months with the same or 1-4 increased doses for better glycemic variability. Results: Out of 10 subjects, the changes in HbA1c showed a decrease in 7, stable in 2, and an increase in 1. HbA1c value was 6.2 ± 0.8% in average at 6 months. There were no remarkable adverse effects by Xultophy for 6 months. Discussion and Conclusion: Xultophy was started at 5-12 doses, which were remarkably lower doses than usual doses with satisfactory efficacy. One of the reasons may be from the characteristic of the patients, who were diabetic with undergoing hemodialysis. Another factor is possibly from liraglutide, which has hepatic clearance with potential vascular protective effects. These results are expected to become reference data for future research

Sustainable cooling method for machining titanium alloy

Hard to machine materials such as Titanium Alloy TI-6AI-4V Grade 5 are notoriously known to generate high temperatures and adverse reactions between the workpiece and the tool tip materials. These conditions all contribute to an increase in the wear mechanisms, reducing tool life. Titanium Alloy, for example always requires coolant to be used during machining. However, traditional flood cooling needs to be replaced due to environmental issues, and an alternative cooling method found that has minimum impact on the environment. For true sustainable cooling of the tool it is necessary to account for all energy used in the cooling process, including the energy involved in producing the coolant. Previous research has established that efficient cooling of the tool interface improves the tool life and cutting action. The objective of this research is to determine the most appropriate sustainable cooling method that can also reduce the rate of wear at the tool interface

Carnitine for Body Composition in Hemodialysis Patients

Background: Authors and colleagues have continued clinical research for hemodialysis patients. Currently, a pilot study presents intervention of carnitine for changes of the body composition. Subjects and Methods: Subjects were six patients on hemodialysis with intervention of carnitine (group 1). Average data were 74.3 years, 65.4 kg, 22.6 in BMI. As levocarnitine, L-Cartin FF injection 1000 mg was administered three times a week for six months. Group 2 has six control patients for age-, sex-, body weight, BMI-matched (group 2). Body composition of muscle and fat tissues were measured by InBody 770 on 0 and 6 months. Results: In group 1, muscle volume and skeletal muscle showed increasing tendency without statistical significance. In contrast, there were significant decreases of body fat volume (22.3 kg vs 20.5 kg, 39.0% vs 35.8%) (p<0.05). No significant differences were found in hemoglobin, total protein, albumin and Cardio-Thoracic Ratio (CTR) of chest X-ray. Group 2 showed no significant changes. Discussion and Conclusion: Hemodialysis patients often have muscular reduction. Previous reports showed improved lean body mass by carnitine administration, which may support our result. These results from current pilot study would be expected to become useful reference data in the pathophysiological investigation in patients on hemodialysis

Machining of Hardened Steels with Ceramic Cutting Tools

application/pdfTurning and milling tests of hardened plain and alloy steels (JIS S55C and JIS SNCM630) with TiC added ceramic tools are conducted and compared with carbide tools. Tool wear or disintegration of cutting edges are observed precisely under various cutting conditions and obtained tool life data are analyzed in order to evaluate the cutting performance of ceramic tools in machining of hardened steels. From these experiments, excellent performance of ceramic tools in turning test is reported. Also some specific facts and suggestions are proposed for the successful use of ceramic tools in face milling of steels.departmental bulletin pape

Wear of Ceramic Tools in Grooving of Plain Carbon Steel

application/pdfIn order to invesigate the grooving performance of ceramic insert tools, cutting test was conducted on low and medium carbon steel under various conditions. Wear patterns, wear rates and chip shapes were observed precisely about tools of several chip breakers. Main results obtained were as follows; 1) The failure of ceramic tools in grooving operation largely depends on the generation and disposal of the chip, and segregation of tool rake face near the cutting edge easily occurs on brittle tools. In grooving low carbon steel, side flank face tends to break because of the adhesion of work material. 2) It is possible to use TiC added ceramic tools for grooving medium carbon steel. Also slanted rake face tools show good results for practical deep grooving. In these cases, emulsion type cutting fluid works effectively to dispose of chips and improve the surface roughness, but tends to increase the rake face chipping of the tool.departmental bulletin pape