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This study aims to enhance the H2/N2 separation performance of polysulfone (PSF) hollow fiber membranes by annealing. X-ray diffraction, SEM, and FESEM were utilized to evaluate morphological and structural changes in denser annealed PSF membranes. AFM topography images were used to investigate the annealed form and roughness of PSF membranes. Before testing membrane permeation, it was annealed at 120, 150, and 190 °C to optimize gas separation performance. Compare to all annealing temperatures (120, 150, and 190 °C), the annealed PSF membrane at 150 °C had the greatest H2/N2 selectivity (16.18), but its separation performance was unsatisfactory since it was below the Robeson upper limit curve. The PSF before annealing and the PSF annealed at 190 °C showed outstanding separation performance (2.60 and 2.71, respectively), despite their lower selectivity than the PSF annealed at 150 °C

Purification of functional DNA nanostructures is an essential step in achieving intended functions because misfolded structures and the remaining free DNA strands in a solution can interact and affect their behavior. However, due to hydrophobicity-mediated aggregation, it is difficult to purify DNA nanostructures modified with hydrophobic molecules by conventional methods. Herein, we report the purification of cholesterol-modified DNA nanostructures using a novel surfactant-assisted gel extraction. The addition of sodium cholate (SC) to the sample solution before structure folding prevented aggregation, which was confirmed by gel electrophoresis. We also found that adding sodium dodecyl sulfate (SDS) to the sample inhibited structural folding. The cholesterol-modified DNA nanostructures prepared with SC were successfully purified by gel extraction, and their ability to bind to the lipid membrane surfaces was maintained. This method will facilitate the purification of DNA nanostructures modified with hydrophobic molecules and expand their applicability in the construction of artificial cell-like systems.

Seaweeds are some of the principal primary producers of marine environments, and they are important ecological elements of coastal ecosystems. The effects of harmful chemicals on seaweeds may adversely affect coastal ecosystems, hence we aimed to develop a new phytotoxicity test using the gametophytes of a common temperate kelp species, Undaria pinnatifida (KU-1630), for the widely used antifouling chemical substances Cybutryne, Diuron, Cu

We demonstrate remote-controlled microflow using photoresponsive DNA fluid. The DNA fluid was fabricated through the self-assembly of branched DNA motifs, nanostructures of base-paired single-stranded DNAs (ssDNAs): Three ssDNAs hybridized in the stem region to form a branched motif possessing sticky ends (SEs); via the hybridization of SEs, the branched DNA motifs self-assembled into DNA fluid, which was micrometer-scale condensates. The motifs were equipped with a photoresponsive capability by introducing azobenzene (Azo), well-studied photoisomerizable compound44, in the SEs. The photoswitchable Azo isomerization enabled the reversible association/dissociation between branched DNA motifs, leading to photoreversible fluidity regulation via gel–liquid–dispersed state transition. To design an energy-transducing system, we exploited the following sequence-specific programmability of DNA. By cross-linking the photoresponsive DNA motif with a branched DNA motif possessing nonphotoresponsive orthogonal SEs, we achieved photocontrollable “transporter” DNA and “cargo” DNA fluids; the photoresponsive DNA fluid hydrodynamically performed mechanical actions upon the nonphotoresponsive DNA fluid by transducing light energy. Notably, we discovered multiple modes in the generated fluid’s mechanical action as a function of the applied temperature and the Azo insertion site in the SE. Each flow mode was characterized as a single-peak-shaped profile in the temperature-dependent flow mobilities. The highest and lowest mobilities were obtainable in moderate and lower and higher temperature ranges, respectively. This anomalous profile was analogous to the reentrant phase behavior of DNA microstructures41,50,51, which behave as solid-like only in a moderate temperature range and as liquid-like in the lower and higher temperature ranges. Following thermodynamic arguments on the observed reentrancy, we describe the observed flow-mobility behavior as a manifestation of a transient non-equilibrium state in the SEs binding stability. We also explain the mode-changeability of the mechanical actions with experimental support by explaining the role of the Azo insertion site in the SE in determining the degree of the nonequilibrium in the binding stability.

Intaking molecular information from the external environment is essential for the normal functioning of artificial cells/molecular robots. Herein, we report the design and function of a membrane nanopore using a DNA origami square tube with a cross-section of 100 nm2. When the nanopore is added to a giant vesicle that mimics a cell membrane, the permeation of large external hydrophilic fluorescent molecules is observed. Furthermore, the addition of up to four ssDNA strands enables size-based selective transport of molecules. A controllable artificial nanopore should facilitate the communication between the vesicle components and their environment.

Nanoscale heat conduction is limited by surface scattering of phonons but can be enhanced by surface phonon-polaritons (SPhPs), which are the hybridization of photons and optical phonons in polar materials. Here, we analyze the dispersion of SPhPs in a multilayer system consisting of a silicon (Si) layer sandwiched between two silicon dioxide (SiO2) nanolayers. We find that SPhPs generated in SiO2 nanolayers couple with guided resonant modes and propagate mainly in the nonabsorbent Si layer for microscale Si thicknesses. This coupling yields an enhancement in thermal conductivity with Si thickness. In contrast, for nanoscale Si thicknesses, evanescent components of SPhPs couple inside the Si layer, resulting in a higher thermal conductivity for thinner Si layers. The transition between these two different coupling phenomena provides the minimum of the in-plane SPhP thermal conductivity at a Si thickness of approximately 1 μm. Our finding brings deeper insight into thermal management in electronics and semiconductors.

Efficient heat dissipation in micro/nano electronics requires long-distance propagation of heat carriers operated above room temperature. However, thermal phonons—the primary heat carriers in dielectric nanomaterials—dissipate the thermal energy after just a few hundred nanometers. Theory predicts that the mean free path of surface phonon-polaritons (SPhPs) can be hundreds of micrometers, which may improve the overall dissipation of heat in nanomaterials. In this work, we experimentally demonstrate such long-distance heat transport by SPhPs. Using the 3[Formula: see text] technique, we measure the in-plane thermal conductivity of SiN nanomembranes for different heater-sensor distances, membrane thicknesses, and temperatures. We find that thin nanomembranes support heat transport by SPhPs, as evidenced by an increase in the thermal conductivity with temperature. Remarkably, the thermal conductivity measured 200 μm away from the heater is consistently higher than that measured 100 μm closer. This result suggests that heat conduction by SPhPs is quasi-ballistically over at least hundreds of micrometers. Our findings pave the way for coherent heat manipulations above room temperature over macroscopic distances, which impacts the applications in thermal management and polaritonics.

Background Blood pressure (BP) variability has reportedly been a risk factor for various clinical events. To clarify the influence of BP visit‐to‐visit variability on adverse events in patients with nonvalvular atrial fibrillation, a post hoc analysis of the J‐RHYTHM Registry was performed. Methods and Results Of 7406 outpatients with nonvalvular atrial fibrillation from 158 institutions, 7226 (age, 69.7±9.9 years; men, 70.7%), in whom BP was measured 4 times or more (14.6±5.0 times) during the 2‐year follow‐up period or until occurrence of an event, constituted the study group. SD and coefficient of variation of BP values were calculated as BP variability. Thromboembolism, major hemorrhage, and all‐cause death occurred in 110 (1.5%), 121 (1.7%), and 168 (2.3%) patients, respectively. When patients were divided into quartiles of systolic BP‐SD (P =0.015 for thromboembolism; HR, 2.60, 95% CI, 1.36–4.97, P =0.004 for major hemorrhage; and HR, 1.85, 95% CI, 1.11–3.07, P =0.018 for all‐cause death) after adjusting for components of the CHA 2 DS 2 ‐VASc score, warfarin and antiplatelet use, atrial fibrillation type, BP measurement times, and others. These findings were consistent when BP‐coefficient of variation was used instead of BP‐SD. Conclusions Systolic BP visit‐to‐visit variability was significantly associated with all adverse events in patients with nonvalvular atrial fibrillation. Further studies are needed to clarify the causality between BP variability and adverse outcomes in patients with nonvalvular atrial fibrillation. Registration URL: https://www.umin.ac.jp/ctr/ ; Unique Identifier: UMIN000001569.

The sense of strangeness (or discomfort) perceived in certain virtual characters, discussed in Uncanny Valey (UV) theory, can be a key factor in our perceptual and cognitive discrimination. Understanding how this strangeness happens is essential to avoid it in the process of modeling virtual humans. In this paper, we investigate the relationship between images features and the discomfort that human beings can perceive. We extract image features based on Hu Moments (Hum) and Histogram Oriented Gradient (Hog). The saliency detection is also extracted in the specific parts of the virtual face. Finally, a model using Support Vector Machine (SVM) to provide binary classification is suggested. The results indicate accuracy of around 80% in the image estimation process comparing with subjective classification. As a contribution, some areas may benefit from this study for avoiding the creation of characters that may cause strangeness, such as the games, conversational agents and cinema industry.

Biochemical systems in living cells have their optimum concentration ratio among each constituent element to maintain their functionality. However, in the case of the biochemical system with complex interactions and feedbacks among elements, their activity as a system greatly changes by the concentration shift of the entire system irrespective of the concentration ratio among elements. In this study, by using a transcription-translation (TX-TL) system as the subject, we illustrate the principle of the nonlinear relationship between the system concentration and the activity of the system. Our experiment and simulation showed that shifts of the system concentration of TX-TL by dilution and concentration works as a switch of activity and demonstrated its ability to emerge a biochemical system to confer the permeability of small molecules to liposomes. These results contribute to the creation of artificial cells using the switch and provide an insight into the birth of the origin of life.

Here, we report on the design and function of a membrane nanopore through a DNA origami square tube with a cross-section of 100 nm2 . When the nanopore is added onto the giant vesicle membrane, the permeation of hydrophilic fluorescent molecules was observed. It can be sealed by the existence of the four specific single strand DNAs. A controllable artificial nanopore should help to communicate the vesicle components with their environment

We demonstrate a method of pattern formation based on an artificial reaction diffusion system in hydrogel medium. By designing both the reaction term and the diffusion term of the system, we have succeeded in generating a sustainable DNA pattern in the gel. A DNA logic gate anchored in the gel detected the diffused molecules from distant source points to mark the equidistant region from the source points, which produced a Voronoi pattern in the gel. Combined with a diffusion modulation method for DNA molecules, the Voronoi pattern was modified as a weighted Voronoi pattern with different morphologies. The proposed framework will be useful in designing a structured gel system responsive to molecular signals.

An isothermal amplification circuit for specific DNA molecules was implemented in giant unilamellar vesicles. Using this circuit, over 5000-fold amplification of output DNAs was achieved, and the amplification behaviour depended on the concentration of input signal DNAs in a cell-sized compartment. Moreover, initiation of the amplification by photo-stimulation was demonstrated.

The most common way to fabricate DNA nanostructures is to mix individually synthesized DNA oligomers in one pot. However, if DNA nanostructures could be produced through enzymatic reactions, they could be applied in various environments, including in vivo. Herein, an enzymatic method developed to construct a DNA nanostructure from a simple motif called a T-motif is reported. A long, repeated structure was replicated from a circular template by rolling circle amplification and then cleaved into T-motif segments by restriction enzymes. These motifs have been successfully assembled into a ladder-like nanostructure without purification or controlled annealing. This approach is widely applicable to constructing a variety of DNA nanostructures through enzymatic reactions.