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Roads are a fundamental component of societal infrastructure, whose decades-long lifespan has far-reaching implications for developmental decisions. The road construction and development have profound impacts on economic growth, social dynamics, and environmental sustainability. Therefore, comprehensive measurement of the current road material stock (MS) and the projection of expected future road scale based on regional socio-economic scenarios that can reflect unique local conditions are necessary. This study examined the historical changes and progression patterns of the road network across Japan from 1965 to 2020 through material flow and material stock analysis. By using the road MS time series, along with explanatory socioeconomic variables, several models including Autoregressive Integrated Moving Average with explanatory variables (ARIMAX), Support Vector Regression (SVR), hybrid ARIMAX-SVR, Multiple Linear Regression (MLR), Artificial Neural Networks (ANN), and Random Forest (RF) were compared. After comparison analysis, ARIMAX and hybrid ARIMAX-SVR models were employed to forecast expected road MS in each prefecture of Japan by 2050 based on national shared socioeconomic pathways (SSP) scenarios. The study found that the total road MS of Japan increased 5.5-fold over 55 years. Aggregate was the dominant material, comprising over 70 % among the four materials of the total road MS. The forecast results for each prefecture were classified into three different patterns. Expected MS in most prefectures still displayed increasing trends in the five scenarios, but the projection of road MS in eight prefectures revealed a notable downward trend across each SSP scenario. For most prefectures, SSP5 displayed the highest expected road MS, followed by SSP1. SSP3 was the scenario with the lowest MS. This approach provided a more thorough understanding of the likely evolution of road MS across different SSP scenarios and could help inform decisions for resource allocation and policy formulation concerning road infrastructure management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Purification of basic drugs in reversed-phase mode is often difficult, mainly due to adsorption of positively charged compounds to the silica gel-based stationary phase. Since this adsorption can be suppressed under alkaline condition, columns with alkali-resistance are required. In addition, compounds with acid-sensitive structures are sometimes degraded during separation on silica gel-based columns which exhibit acidity due to their surface structure. We prepared an alkali-resistant reversed-phase packing material, Eggshell-PMAcO based on eggshells modified with an amphiphilic copolymer, poly(maleic acid-alt-1-octadecene) (PMAcO). The height equivalent to a theoretical plate (HETP) of the Eggshell-PMAcO column was improved by surface treatment with ammonium acetate buffer (900 mM, pH = 3.7), which is an inexpensive reagent, and the retention behavior for hydrophobic compounds was compared to a typical ODS column based on silica gel, resulting in sufficient selectivity of the eggshell-based column for hydrophobic compounds, as indicated by the ratio of retention factors of pentylbenzene and butylbenzene (Eggshell-PMAcO column: 1.55, ODS column: 1.65). Column temperature-dependent retention behavior of naphthalene was investigated in the temperature range from 25 °C to 45 °C, followed by the calculation of thermodynamic parameters. There was little difference in the standard molar enthalpy (Eggshell-PMAcO: -19.6 kJ/mol, ODS: -21.7 kJ/mol). The absolute value of the standard free Gibbs energy for the Eggshell-PMAcO column was much smaller than that of the ODS column (Eggshell-PMAcO: -0.284 kJ/mol, ODS: -13.0 kJ/mol), indicating that the Eggshell-PMAcO column had a weaker retention strength for naphthalene than the ODS column mainly due to the large difference in the standard molar entropy (Eggshell-PMAcO: -64.9 J/mol K, ODS column: -29.2 J/mol K). The retention capacities for imipramine under neutral (water/methanol) and alkaline (0.1% triethylamine water/methanol) conditions were 0.2 mg and 5 mg, respectively, based on injection mass-dependent HETP, retention factor and symmetry factor. Finally, the prepared column was applied to the purification of a building block for nucleic acid drugs. This study demonstrated that reversed-phase columns, which can be fabricated from eggshells and an amphiphilic copolymer in an inexpensive and eco-friendly way, have the ability to purify basic compounds and acid-sensitive compounds., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Considering the vulnerability of silica gel to alkaline mobile phases, a highly alkaline stable stationary phase for HPLC is required to separate basic compounds with high separation efficiency. To address this issue, we have developed a high alkaline stable packing material (CaCO 3 -PMAcO) based on mesoporous calcium carbonate microspheres modified with poly(maleic acid-alt-1-octadecene). In this study, we report further investigation of the separation performance of CaCO 3 -PMAcO column by systematically evaluating the effects of particle size and chromatographic conditions. Based on the theory of the van Deemter equation, the separation efficiency was related to the size of CaCO 3 -PMAcO particles (2.9 - 5.7 µm). The evaluation of thermodynamics of retention by changing the column temperature from 20 °C to 45 °C implied that the retention mode was dominated by hydrophobic interaction associated with the exothermic enthalpy changes (-11.1 to -12.5 kJ/mol). The results of column selectivity tests revealed that the CaCO 3 -PMAcO column had hydrophobic selectivity comparable to C 18 silica gel columns (α P/B ; CaCO 3 -PMAcO column: 1.53, C 18 column: 1.69), and higher shape/steric selectivity (α Tri/Ter ; CaCO 3 -PMAcO column: 1.56, C 18 column: 0.955). In practice, the CaCO 3 -PMAcO column could be applied to the separation of not only alkylbenzenes and polycyclic aromatic hydrocarbons, but also to basic tricyclic antidepressants by using an alkaline mobile phase (pH 12)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The demand for electricity affects the future climate through its effect on greenhouse gas emissions in the electricity generation process, but climate change also impacts electricity demand by changing the need for heating and cooling. Developing reliable temperature response functions (TRFs) that illustrate electricity demand as a function of temperature is key for decreasing uncertainty in future climate projections under a changing climate and for impact assessments of climate change on energy systems. However, this task is challenging because electricity demand is determined by multiple factors that interact in complicated ways because demand fluctuations represent timely human responses to given meteorological conditions. We propose a novel method to acquire reliable TRFs at a regional scale based on comprehensive modeling of electricity demand fluctuations. Six candidate algorithms were examined, and multivariate adaptive regression splines (MARS) was selected as the best algorithm with the dataset used. Using MARS, we constructed models with the capacity to precisely reproduce complex electricity demand patterns based on multiple predictors and simulated the impact of temperature on electricity demand while controlling for the effects of other factors. The temporal segments in TRFs are detected and parameters and functional forms of TRFs for 10 regions in Japan were presented., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Although the field of antibody drugs has grown larger, the antibody production still faces several challenges. Effective antibody purification is required, but the conventional purification method for antibodies is cost intensive and often causes aggregation problems, indicating the need for new alternative antibody purification methods. In the present study, a constant temperature antibody purification system for use with a thermo-responsive polymer column was developed based on switching of anion species in eluents. By adjusting the temperature for each antibody, the developed column enabled separation of the therapeutic monoclonal antibodies, rituximab and trastuzumab, from contaminants without changing salt concentration or pH of the eluents. The thermo-responsive hydrogel-modified column packing material was synthesized by introducing n-butyl methacrylate, acrylic acid, N,N'-methylenebisacrylamide and N-isopropylacrylamide to the surface of silica beads with an initiator by a graft-from approach. Elution behavior of antibodies with three types of anions, such as citrate, phosphate, and chloride were tested under three different temperature conditions. It was demonstrated that the thermo-responsive hydrogel grafted column showed a switchable antibody retention behavior at constant temperature and salt concentration, with antibody adsorption by NaCl eluent and desorption by citric acid buffer eluent., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Liposomes composed of egg phosphatidylcholine and cholesterol were modified with the temperature-responsive polymer poly(N-isopropylacrylamide-co-N, N-dimethylacrylamide) (P(NIPAAm-co-DMAAm)), and exhibited reversible surface properties with temperature. Completely reversible liposome aggregation due to P(NIPAAm-co-DMAAm) hydration/dehydration was demonstrated over four successive cycles of heating and cooling. The P(NIPAAm-co-DMAAm) polymer was hydrated during cooling, which dispersed the liposomes. The rigidity of the liposomal membrane was one of the factors in the reversible aggregation, as was the modification density of the polymer on the liposomes. A low density on relatively rigid liposomes could maintain the polymer property of reversible hydrated layers below critical solution temperature (LCST) boundary. Above the LCST, temperature-responsive polymers could also transport negatively charged liposomes into cells. The reversible behavior of the temperature-responsive polymer-modified liposomes has not been reported previously and could enable new applications for switching deposit forms as alternative drug carriers., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Recently, the importance of biopharmaceuticals in medical treatments has been increasing, and effective protein purification methods are strongly required for their production. In the present study, a temperature-responsive solid-phase extraction (SPE) column was developed for the purification of proteins without affecting their bioactivity. A temperature-responsive polymer hydrogel-modified stationary phase was prepared by coating aminopropyl silica beads (average diameter, 40-64 μm) with poly(N-isopropylacrylamide) (PNIPAAm)-based thermoresponsive hydrogels. n-Butyl methacrylate and acrylic acid were copolymerized with PNIPAAm as hydrophobic and anionic monomers, respectively. Using these temperature-responsive SPE columns, targeted proteins were retained on the thermoresponsive hydrogel at 40 °C through hydrophobic and electrostatic interactions. After the temperature was reduced from 40 °C to 4 °C, the retained proteins were successfully eluted from the column. Using the temperature-responsive SPE system, lysozyme was successfully separated from ovalbumin without any loss in bioactivity (99.7 ± 0.1%). Rituximab, a monoclonal antibody, was also purified from BSA or hybridoma cell culture medium using the prepared SPE column. Denaturation of rituximab was not observed in the rituximab fraction eluted from the SPE column. These results demonstrate that temperature-responsive polymer-based SPE can be applied in biomedical purifications, while maintaining the biological activity of the proteins., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This study reports the development of temperature-responsive polymer/silica hybrid nanoparticles and their application to temperature-dependent intracellular uptake of hydrophobic encapsulated fluorescence molecules. Amphiphilic diblock copolymer comprising a temperature-responsive segment, poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide) [P(NIPAAm-co-DMAAm)] and a trimethyoxysilyl-containing hydrophobic segment was synthesized (PBM-b-ND); this amphiphilic diblock copolymer self-assembled in an aqueous solution, and temperature-responsive polymer/silica hybrid fluorescence nanoparticles were fabricated via a base-catalyzed sol-gel process. The fluorescence probe rhodamine DHPE or boron dipyrromethene derivative was encapsulated into the polymer core with a silica network in a stable manner. Other types of polymer/silica hybrid fluorescence nanoparticles were also developed using either homo-PNIPAAm (PBM-b-N) or homo-PDMAAm (PBM-b-D) segments, instead of P(NIPAAm-co-DMAAm). While PBM-b-D did not exhibit a temperature-dependent phase transition (hydrophilic characteristic), PBM-b-N and PBM-b-ND exhibited temperature-dependent phase transition (hydrophilic/hydrophobic) at 32°C and 38°C, respectively. The cellular uptake of PBM-b-N was clearly observed at both 37°C and 42°C, while the cellular uptake of PBM-b-D was minimal at these temperatures. On the other hand, significant enhancement in the intracellular uptake of PBM-b-ND was observed at 42°C, compared to its uptake at a lower temperature of 37°C. These results indicated that temperature-responsive polymer/silica hybrid nanoparticle, PBM-b-ND demonstrate potential for applications in theranostics with cancer therapy via the combination of local drug delivery and local hyperthermia, as well as for monitoring treatment effectiveness with fluorescence imaging., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Poly(N-isopropylacrylamide) (PNIPAm) is one of the most widely studied temperature-responsive polymers among those that have been applied to biomaterials science and technology. Here, we investigated the importance of interactions between PNIPAm-based copolymers and biological factors. The effects of a series of major anionic electrolytes in biological environments and of human serum albumin (HSA) on the lower critical solution temperature (LCST) of homo-PNIPAm and PNIPAm copolymers were studied, using either a hydrophobic monomer or a cationic monomer. We synthesized P(NIPAm-co-BMA3%) with butyl methacrylate (BMA) as a hydrophobic monomer and P(NIPAm-co-DMAPAm2%) with N,N-dimethylaminopropyl acrylamide (DMAPAm) as a cationic monomer. The LCST of PNIPAm and P(NIPAm-co-DMAPAm2%) decreased with increasing salt concentrations, and the effects of anions on each polymer corresponded to the Hofmeister series. The LCST of P(NIPAm-co-DMAPAm2%) was greatly affected by anionic electrolytes compared with those of homo-PNIPAm and P(NIPAm-co-BMA3%). While the LCST of homo-PNIPAm was not affected by HSA, the LCST of P(NIPAm-co-DMAPAm2%) decreased non-linearly with increasing HSA concentrations. These effects were due to the electrostatic interactions between the positively charged polymer chains and the negatively charged HSA, as well as the stabilization of polymer aggregations with HSA. Under physiological buffer conditions, the LCST of P(NIPAm-co-DMAPAm2%) was not significantly affected by the HSA concentration. These results indicated that depending on the types of copolymers used for biological applications, it is necessary to take into account the effect of biological media while designing polymers., (Copyright © 2015 Elsevier B.V. All rights reserved.)