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This study proposes a wearable device that adapts its surface conditions to maximize user comfort using novel strategies to change its temperature, humidity, and friction. The device consists of three functional units, namely heating, liquid injection, and dry-air blowing units, composed of flexible materials and thin structures. Owing to its flexibility and thickness, it can be installed on garments. The surface conditions change according to the collaborative actions of the three functional units. The temperature is increased using the heating unit and decreased using both the liquid-injection and dry-air blowing units. Humidity is increased and decreased by the liquid-injection and dry-air blowing units, respectively. Finally, the friction of the contact surface area of the device with human skin is increased and decreased using the liquid-injection and dry-air blowing units, respectively. These methodologies are experimentally validated under different environmental conditions. The validation reveals that the injection of a liquid (deionized water) increases surface friction, whereas blowing air decreases friction; in particular, the presence of granular objects is effective at reducing friction. In addition, the environmental conditions of temperature and humidity influence the degree of increase or decrease, primarily because the amount of water is varied to change the humidity, lower the temperature, and increase friction: vaporization heating lowered temperature and adhesion force of water increased friction. The temperature, humidity, and kinetic friction of the wearable device range from −2.6 to +5.0 °C, −19% to +12%, and −73% to +45%, respectively.

N-nitrosamines, which are well-known pro-mutagens, are found in drugs, pickled food and tobacco. Therefore, controlling their concentrations is very important. When an HPLC, GC or NMR analysis is conducted to investigate certain asymmetrical N-nitrosamines, two sets of signals attributed to the asymmetric N-nitrosamine isomers are usually observed. However, few reports on the NMR assignment of asymmetrical N-nitrosamine isomers have been published. In this study, we investigated the NMR assignments of the Z/E isomers of six asymmetrical N-nitrosamines by means of density functional theory (DFT) calculations. The configuration of the major isomer of asymmetrical N-nitrosamine 3 was the Z-configuration. The configuration of the major isomers of asymmetrical N-nitrosamines 4–7 was the E-configuration. Then, we determined the Z/E ratios of these asymmetrical N-nitrosamines by means of variable temperature (VT) and room temperature (RT) 1H-NMR experiments. The ratios of the Z/E isomer 3 quickly increased beyond 100% in the VT 1H NMR experiments. The ratios of Z/E isomers 4–7 were increased in the range of 10–60% in the VT 1H NMR experiments. The results of this study indicate that identifying the isomers of asymmetrical N-nitrosamine is necessary to control the quality of N-nitrosamines for active pharmaceutical ingredients (APIs).

Supramolecular liquid crystals (SLCs) are attractive materials for fabricating devices with new optoelectronic functions. Conventional SLCs are made from hydrogen‐bonded mesogens. However, these mesogens suffer from high melting points, and the types of formable aggregates are limited owing to the directionality of the hydrogen bonding. Therefore, to fabricate non‐hydrogen‐bonded SLCs, we hypothesized that the introduction of tertiary amide groups into calamitic molecules would be advantageous because they have an L‐shaped structure with N‐ or C‐alkyl side chains not aligned along the long axis and the flexibility to undergo cis–trans isomerization. In this study, we developed a novel non‐hydrogen‐bonded SLC by assembling an L‐shaped dimer composed of calamitic molecules (phenyltolanes) with tertiary amides at their ends. These molecules exhibited a smectic B phase. The phase transition temperature of the SLCs from crystal to liquid crystal phase was low despite the long π‐conjugated core. Wide‐angle X‐ray diffraction and variable‐temperature Fourier‐transform infrared measurements revealed dimer formation by weak intermolecular interactions, that is, the molecular recognition of L‐shaped molecules, and mobility of the alkyl groups attached to amide driven by cis–trans isomerization in the liquid crystal phase. Thus, cis–trans isomerization of tertiary amides contributed enormously to the formation and lower clearing points of this SLC. The developed method can be used not only to develop non‐hydrogen‐bonded SLCs but also to develop novel soft matter with controlled properties by incorporating the SLCs, as the aggregates can be controlled to impart desired functionalities. Supramolecular liquid crystals (SLCs) are attractive materials for fabricating devices with new optoelectronic functions. In this study, we developed a novel non‐hydrogen‐bonded SLC by assembling an L‐shaped dimer composed of calamitic molecules (phenyltolanes) with tertiary amides at their ends.

X-ray crystallography enables detailed structural studies of proteins to understand and modulate their function. Conducting crystallographic experiments at cryogenic temperatures has practical benefits but potentially limits the identification of functionally important alternative protein conformations that can be revealed only at room temperature (RT). This review discusses practical aspects of preparing, acquiring, and analyzing X-ray crystallography data at RT to demystify preconceived impracticalities that freeze progress of routine RT data collection at synchrotron sources. Examples are presented as conceptual and experimental templates to enable the design of RT-inspired studies; they illustrate the diversity and utility of gaining novel insights into protein conformational landscapes. An integrative view of protein conformational dynamics enables opportunities to advance basic and biomedical research.

• Investigating the interaction between environmental heterogeneity and local adaptation is critical for understanding the evolutionary history of a species, providing the premise for studying the response of organisms to rapid climate change. However, for most species how exactly the spatial heterogeneity promotes population divergence and how genomic variations contribute to adaptive evolution remain poorly understood. • We examine the contributions of geographical and environmental variables to population divergence of the relictual, alpine herb Circaeaster agrestis, as well as the genetic basis of local adaptation using RAD-seq and plastome data. • We detected significant genetic structure with an extraordinary disequilibrium of genetic diversity among regions, and signals of isolation-by-distance along with isolation-by-resistance. The populations were estimated to begin diverging in the late Miocene, along with a possible ancestral distribution of the Hengduan Mountains and adjacent regions. Both environmental gradient and redundancy analyses revealed significant association between genetic variation and temperature variables. Genome–environment association analyses identified 16 putatively adaptive loci related mainly to biotic and abiotic stress resistance. • Our genome-wide data provide new insights into the important role of environmental heterogeneity in shaping genetic structure, and access the footprints of local adaptation in an ancient relictual species, informing future conservation efforts.

A thermo-responsive cellulose-based material (cellulose-g-PNIPAAm) was prepared by grafting N-isopropylacrylamide (NIPAAm) onto bagasse pulp cellulose via Ce (IV)-initiated free radical polymerization. The surfaces of the obtained cellulose-g-PNIPAAm paper showed a rapid wettability conversion from being hydrophilic (water contact angles (WCA) of 0°) at 25 °C to becoming hydrophobic (WCA of 134.2°) at 45 °C. Furthermore, the thermo-responsive mechanism of cellulose-g-PNIPAAm was examined by the in situ variable-temperature 13C NMR, 1H NMR and AFM analysis. At the same time, the resulting cellulose paper was applied for a switchable separation of oil/water mixtures. Water can pass through the paper under 45 °C, while oil is kept on the paper. When the temperature is above 45 °C, oil can permeate through the paper, while water cannot pass through the water. Moreover, the paper exhibited excellent regeneration performance after five cycles and maintained its switchable wettability.

This article comments on: Annunziata MG, Apelt F, Carillo P, Krause U, Feil R, Koehl K, Lunn JE, Stitt M. 2018. Response of Arabidopsis primary metabolism and circadian clock to low night temperature in a natural light environment. Journal of Experimental Botany 69, 4881-4895.

MHD and thermal radiation effects on unsteady flow past an oscillating semi-infinite vertical plate with variable surface temperature and uniform mass flux have been studied. The dimensionless governing equations are solved by an efficient, more accurate, unconditionally stable and fast converging implicit finite difference scheme. The effect of velocity, concentratiion and temperature profiles for different parameters like magnetic field , thermal radiation, Schmidt number, thermal Grashof number, mass Grashof number are studied. It is observed that the velocity decreases with increasing values of the magnetic field parameter or radiation parameter.

Atomic-resolution cryogenic scanning transmission electron microscopy (cryo-STEM) has provided a path to probing the microscopic nature of select low-temperature phases in quantum materials. Expanding cryo-STEM techniques to broadly tunable temperatures will give access to the rich temperature-dependent phase diagrams of these materials. With existing cryo-holders, however, variations in sample temperature significantly disrupt the thermal equilibrium of the system, resulting in large-scale sample drift. The ability to tune the temperature without negative impact on the overall instrument stability is crucial, particularly for high-resolution experiments. Here, we test a new side-entry continuously variable temperature dual-tilt cryo-holder which integrates liquid nitrogen cooling with a 6-pin micro-electromechanical system (MEMS) sample heater to overcome some of these experimental challenges. We measure consistently low drift rates of 0.3–0.4 Å/s and demonstrate atomic-resolution cryo-STEM imaging across a continuously variable temperature range from ~100 K to well above room temperature. We conduct additional drift stability measurements across several commercial sample stages and discuss implications for further developments of ultra-stable, flexible cryo-stages.

To reveal the mechanisms governing the temperature-dependent electrical behavior of coal-bearing surrounding rocks, a multi-physics coupling model was established and combined with experimental data to systematically analyze the evolution of resistivity and dielectric properties with temperature. The results show that resistivity undergoes a three-stage transformation: it first increases due to microcrack development and pore-water evaporation, then decreases sharply as carriers are thermally activated, and further declines at higher temperatures. Dielectric properties are markedly enhanced beyond a critical threshold, accompanied by a relaxation peak that indicates interfacial and ionic polarization dominate under thermal activation. A pronounced frequency dispersion is also observed, with polarization processes being suppressed at higher frequencies. These findings demonstrate that temperature strongly regulates carrier mobility and polarization capacity, thereby exerting a fundamental influence on the resistivity and dielectric response of rocks. This work provides theoretical support and practical reference for temperature correction in deep resource geophysical exploration, real-time monitoring of thermal damage in mines, and stability assessment of rocks under high-temperature conditions.