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A gene normally involved in responding to hypoxia helps to protect insect muscles during migratory flight in a non-oxygen dependent manner.

There is significant interest in high-performance positively charged membranes that enable the fast and high-precision separation of various cationic substances for purifying water and recovering precious metals. This study demonstrates that the ultrafast and precise separation of cations can be achieved using positively charged membranes with fine-controlled nanopores fabricated via a solvent-controlled swelling–diffusion (SD) method. Polyamide (PA) membranes are treated with a dimethyl sulfoxide/water mixture solvent containing a rationally designed, positively charged strong polyelectrolyte, followed by water washing. Solvent-induced PA activation and polyelectrolyte incorporation into PA cooperatively produce a highly-permeable and more uniform PA nanopore structure with a strong and stable positive surface charge. Consequently, the SD-modified membrane exhibits unprecedentedly high water permeance (∼22 L m−2 h−1 bar−1) and high rejection (∼99.5% for MgCl2, >90% for hazardous metals) and selectivity (∼23.4 for Li+/Mg2+) for divalent cations, significantly outperforming commercial and previously reported membranes. Our proposed strategy provides a commercially viable means for the fabrication of high-performance functional membranes and coatings and sheds light on their structure–performance relationship.

This study was performed to investigate the effect of microbial supplementation diet on the survival rate and microbiota composition of artificially produced eel larvae. Microorganisms supplemented in the diet were isolated from wild glass eel intestines and identified as

The freshwater eel Anguilla japonica is rapidly decreasing in number and has not yet been successfully mass produced. This may be at least partially attributable to the unique and long early life history of the eel. Therefore, we investigated its ontogeny of morphometry and growth pattern in larval stages to provide baseline information for understanding the early life history and improving seed rearing technology. This study was conducted for 200 days after hatching (DAH) and analyzed morphometry and allometry for eel larvae. The following cultured eel larval stages were identified: the yolk sac larvae stage (0–6 DAH, 3.23–6.85 mm total length (TL)), the pre-leptocephalus stage (7–30 DAH, 6.85–15.31 mm TL), and the leptocephalus stage (50–200 DAH, 15.31–60.06 mm TL). Cultured and wild eel larvae could be divided into characteristic larval stages at similar sizes. However, compared to wild eels, cultured eels had a slower growth rate and fewer preanal myomeres. Meanwhile, cultured eel larvae rarely had a mixed feeding period as the absorption of endogenous reserves was completed by 7 DAH. The lower jaw of eel larvae was significantly longer than the upper jaw from 50 DAH. In the pre-leptocephalus and leptocephalus stages, eel larvae showed continuous positive allometric growth at trunk height and tail muscle height with change to the willow leaf-like form. These growth characteristics may be the result of adaptation to the migration over long distances and to a diel vertical migration. The inflection point in the body parts growth patterns showed only before 30 DAH, and mass mortality appeared at this period. Therefore, to improve the growth and survival rates of cultured eel seed, it is necessary to focus on improving the feeding and rearing protocol until 30 DAH.

Ultrathin and smooth polyamide (PA) reverse osmosis (RO) membranes have attracted significant interest due to their potential advantages of high permeance and low fouling propensity. Although a layered interfacial polymerization (LIP) technique aided by the insertion of a polyelectrolyte interlayer has proven effective in fabricating ultrathin and uniform membranes, the RO performance and pH stability of the fabricated LIP membrane remain inadequate. In this study, a poly(piperazineamide) (PIPA) layer prepared via interfacial polymerization (IP) was employed as an interlayer to overcome the limitations of the prototype LIP method. Similar to the control polyelectrolyte-interlayered LIP membrane, the PIPA-interlayered LIP (pLIP) membrane had a much thinner (~20 nm) and smoother selective layer than the membrane fabricated via conventional IP due to the highly surface-confined and uniform LIP reaction. The pLIP membrane also exhibited RO performance exceeding that of the control LIP and conventional IP-assembled membranes, by enabling denser monomer deposition and a more confined interfacial reaction. Importantly, the chemically crosslinked PIPA interlayer endowed the pLIP membrane with higher pH stability than the control polyelectrolyte interlayer. The proposed strategy enables the fabrication of high-performance and pH-stable PA membranes using hydrophilic supports, which can be applied to other separation processes, including osmosis-driven separation and organic solvent filtration.

The incorporation of an atomic-layer-deposited Al2O3 capping layer was proposed as an effective method to enhance the electrical performance and stability of p-channel SnO thin-film transistors (TFTs). The SnO TFT with the Al2O3 capping layer demonstrated better electrical characteristics, such as higher field-effect mobility ( $\mu _{\mathrm {FE}} =1.7$ cm2/ $\text{V}\cdot \text{s}$ ), smaller subthreshold swing ( SS =2.9 V/dec), and larger current on/off ratio ( $I_{\mathrm {ON/OFF}} = 1.6\times 10^{4}$ ), than the pristine SnO TFT ( $\mu _{\mathrm {FE}} =1.5$ cm2/ $\text{V}\cdot \text{s}$ , SS =3.8 V/dec, and $I_{\mathrm {ON/OFF}} = 6.9\times 10^{2}$ ). Furthermore, the Al2O3-capped SnO TFT exhibited significantly enhanced electrical stability under an applied negative-gate-bias stress compared to the pristine device. The observed phenomena were mainly attributed to the decreased number of oxygen-vacancy-induced hole trap states within the SnO owing to diffused hydrogen from the atomic-layer-deposited Al2O3 layer. Our experimental results thus demonstrate that incorporating the atomic-layer-deposited Al2O3 capping layer is a simple and effective method for improving the electrical characteristics of p-channel SnO TFTs.

The present work investigated the electrical characteristics of Corbino structure p-type tin monoxide (SnO) thin-film transistors (TFTs) and demonstrated a high-performance complementary logic inverter composed of Corbino p-type SnO and n-type indium-gallium-zinc oxide (IGZO) TFTs. Experimental data showed that the Corbino p-type SnO TFT exhibited an almost infinite output resistance beyond pinch-off in the outer drain condition. The observed phenomenon was mainly attributed to the scaling down of the effective channel width in proportion to the effective channel length. By using the very high output resistance of the Corbino structure TFTs, we fabricated the high-gain complementary logic inverter composed of Corbino p-type SnO and n-type IGZO TFTs. The Corbino TFT-based complementary logic inverter showed a voltage gain of 92.4 at a supplied voltage of 10 V, which was significantly higher than that of 18.7 obtained from the complementary logic inverter composed of the conventional rectangular shaped TFTs.

A thin film composite (TFC) forward osmosis (FO) membrane with high performance and superb durability was fabricated on a polydopamine (PDA)-modified polyethylene (DPE) support via an unconventional aromatic solvent-based interfacial polymerization (IP) method. The PDA coating uniformly hydrophilized the hydrophobic pristine polyethylene (PE) support, which enabled the long-term operation stability. The thin (∼8 μm) and highly porous support structure with interconnected pores was preserved after the PDA modification, leading to a remarkably low structural parameter (∼168 μm) of the support. In addition, the use of the toluene-based IP process allowed for the formation of a highly permselective polyamide selective layer on the hydrophilic DPE support, which was challenging with the conventional aliphatic solvent-based IP process. Hence, the prepared DPE-supported TFC (DPE-TFC) membrane exhibited unprecedented high FO performance, i.e., ∼4.5 times higher FO water flux and ∼63% lower specific salt flux (in FO mode) compared to the commercial HTI-CTA membrane. Furthermore, the DPE-TFC membrane possessed superior mechanical robustness, which guarantee durable operability and potential application even in mechanically harsh environments. Hence, the PE-supported FO membrane presents a new paradigm in FO membrane technology.

This present work investigated the effects of proton-beam irradiation on SnO-based p-type oxide thin-film transistors (TFTs) for the first time. The experiments were performed using a 5-MeV proton beam with doses ranging from $10^{12}$ to $10^{14}\,\,\textsf {p}\cdot \textsf {cm}^{-2}$ . The experimental results showed that the transfer curves of the p-type SnO TFT rarely changed following the proton irradiation at every irradiation condition, indicating that the p-type SnO TFT could be potentially useful in implementing complementary-logic-based oxide TFT circuits operating in harsh environments. The insensitivity of current conduction paths to SnO lattice disorder was considered as a possible mechanism for the observed radiation tolerance of the p-type SnO TFTs.

We present a facile method to enhance separation performance of polyamide (PA) reverse osmosis (RO) membranes via solvent activation with a new type of organic solvent, benzyl alcohol (BA). Activation with BA remarkably improved water permeance (up to ∼140% increase) while maintaining high NaCl rejection (∼99.6%) of the pristine RO membrane, thereby overcoming the flux-rejection trade-off limitation. Thus, the water permeance and permselectivity of the BA-activated RO membrane significantly exceeded those of commercial RO membranes. This significant performance enhancement was attributed to the appropriate solvency power of BA (determined based on Hansen solubility parameters), which led to the balanced structural deformation of the PA selective layer; BA activation produced a less dense and highly permeable PA structure by greatly swelling PA, while simultaneously healing loosened sites via structural compaction of the PA network with a sufficiently reduced modulus. Based on the activation results with various organic solvents ranging from mild to strong solvents, we propose a more reliable predictor of the solvent activation effect. Our strategy is a simple, effective and commercially viable method to enhance RO membrane performance. Additionally, our study highlights on the underlying solvent activating mechanism of PA RO membranes.

A high performance thin film composite (TFC) forward osmosis (FO) membrane was prepared using a hydrophilic polyacrylonitrile (PAN) support with a tailored structure via a newly devised, aromatic solvent (toluene)-based interfacial polymerization (TIP) technique. The use of toluene as the organic solvent promoted amine diffusion toward the organic phase and the subsequent reaction, leading to the formation of an ultrathin (highly permeable) and highly dense (highly selective) polyamide selective layer on the PAN support, which improved membrane performance. In addition, a relatively thin (∼80 μm) and finger-like porous support structure embedded with a nonwoven fabric was favorable for facilitating mass transport in the support. As a result, the TFC FO membrane prepared via TIP showed ∼2.1 times higher FO water flux and ∼68% lower specific salt flux than the membrane prepared via conventional aliphatic solvent-based interfacial polymerization (IP) in FO mode. Importantly, our TIP-assembled membrane exhibited superior FO performance over commercial and other lab-made membranes. Our strategy provides a facile solution to overcome the technical limitations of the conventional IP method by enabling the fabrication of high performance PA layers on hydrophilic supports, expanding the application spectrum of TFC membranes.

The state-of-the-art thin film composite (TFC) reverse osmosis (RO) membranes suffer from unsatisfactory boron rejection and a high fouling propensity, which reduce the process efficiency, necessitating the development of a new membrane chemistry using advanced materials. In this study, we designed a core–shell structured, poly(acryloyl hydrazide)-grafted cellulose nanocrystal (CNC-PAH) as a new building material that can be assembled into a RO membrane with high selectivity and low fouling via the layered interfacial polymerization (LIP) technique. The LIP method allowed for the uniform, dense and strong deposition of the CNC-PAH particles on a support. The high density reactive functional groups provided by the densely-packed CNC-PAH enabled the formation of a highly cross-linked and permselective network, leading to the fabrication of a TFC membrane with water permeance and NaCl rejection comparable to those of the commercial RO membrane. Importantly, the boron capturing ability endowed by the abundant hydroxyl and amine groups remaining in CNC-PAH improved boron rejection of the membrane, which exceeded that of the commercial membrane. Furthermore, along with the higher surface smoothness of the CNC-PAH-assembled membrane, its higher hydrophilicity and greater negative surface charge remarkably enhanced organic fouling resistance compared to the commercial membrane.

A polyamide (PA) thin film composite (TFC) reverse osmosis (RO) membrane having high permselectivity and excellent mechanical/chemical durability was prepared using a polyethylene (PE) support. Although the PE support's uniform pores and high surface porosity are beneficial for enhancing membrane permselectivity, its intrinsic hydrophobicity makes the fabrication of a PA selective layer challenging. An oxygen plasma treatment on the PE support, combined with using a sodium dodecyl sulfate (SDS) during interfacial polymerization, allowed a PA layer to be formed on the support due to by enhancing its water wettability. The systematic optimization of the membrane fabrication parameters (e.g., plasma pretreatment, monomer and SDS compositions and post-heat treatment) achieved high membrane performance. The fabricated PE-supported membrane (TFC-PE) showed ~30% higher water flux with ~0.4% enhancement in NaCl rejection compared to a commercial RO membrane. Furthermore, the TFC-PE membrane had mechanical properties and organic solvent resistance superior to the commercial membrane, which is attributed to the excellent mechanical and chemical stability of the PE material. The proposed strategy could expand the application of RO membranes to mechanically and chemically harsh operating environments.

We report an aromatic solvent-assisted interfacial polymerization (IP) method to prepare high performance thin film composite reverse osmosis (RO) membranes based on a polyacrylonitrile support. The use of toluene and xylene as an organic solvent phase led to excellent water flux and unprecedentedly high NaCl rejection (∼99.9%), exceeding both the control membrane prepared using a conventional aliphatic solvent (n-hexane) and commercial RO membranes. The membrane prepared using n-hexane had a thick and moderately dense PA layer, due to the limited amine monomer diffusion, accounting for its relatively low performance. In contrast, the membranes fabricated using toluene/xylene had roof-like structures covering a thin and highly dense basal PA layer, which was formed by increased amine diffusion and an expanded miscible interface zone resulting from the enhanced miscibility of toluene/xylene with water. The excellent membrane performance achieved using toluene/xylene can be attributed to the thin and highly cross-linked basal PA layer.

Trace organic compounds (TOrCs) have emerged as a critical concern for securing high-quality and safe water resources. Advanced water treatment using reverse osmosis (RO) and nanofiltration (NF) membranes has proven to be a promising technology for removing TOrCs. In this context, identifying the TOrC rejection mechanisms of RO/NF membranes is of paramount importance for the effective design of membrane processes and materials to improve the efficiency of TOrC treatment. However, the characteristic TOrC removal mechanisms of RO/NF membranes remain unclear, presumably due to the vast differences in the membrane structures and the limited number of TOrCs that have been investigated in past studies. Hence, the present article comprehensively reviews, analyzes and elucidates TOrC rejection mechanisms by characterizing key rejection-governing solute parameters for fully-aromatic polyamide-based tight RO/NF membranes (MWCO ≤ 200 Da) using the published rejection data for a large number of TOrCs (>300). We found that size exclusion and adsorption (and subsequent partitioning) via specific interactions play a dominant role in TOrC rejection by elucidating the key rejection-governing solute characteristics. In addition, this paper outlines up-to-date research on the fabrication of advanced membranes designed to improve TOrC removal performance. Based on this review, we propose future directions for reliably predicting and effectively enhancing the TOrC separation performance of RO/NF membranes.

Biofouling is a pervasive problem for any materials that are exposed to aquatic environments. Especially, it is a dire problem for the desalination membranes used to sustainably supply clean water, necessitating development of the methods to mitigate membrane biofouling. We present a topological modification approach to achieve ultralow fouling of water desalination membranes by realizing the sharkskin-mimetic (Sharklet) surface patterns and identify their unique antifouling mechanism based on computational fluid dynamics simulation. Our approach relies on a newly developed layered interfacial polymerization that can produce a conformal selective layer on patterned porous supports prepared by phase separation micromolding. The Sharklet-patterned membrane exhibited remarkably low biofouling compared to the conventional membranes with irregular roughness and topologically modulated membranes with simple patterns. Its superior biofouling resistance is attributed to the unique Sharklet geometry that can significantly inhibit biofilm growth. Furthermore, under dynamic flow conditions, the intricate Sharklet geometry induces a complex surface flow by symmetrically generating a secondary flow perpendicular to the primary flow, forming a periodic inflow and outflow along the pattern. The reinforced primary and secondary flows of the Sharklet pattern may further contribute to its excellent biofouling resistance.

Numerous studies have addressed the utilization of oxide thin-film transistor (TFT)-based complementary logic circuits that are based on two-dimensional (2D) planar structures. However, there are fundamental limits to the 2D planar structured complementary logic circuits, such as a large dimension and a large parasitic resistance. This work demonstrated a vertically stacked three-dimensional complementary inverter composed of a p-channel tin monoxide (SnO) TFT and an n-channel indium-gallium-zinc oxide (IGZO) TFT. A bottom-gate p-channel SnO TFT was formed on the top-gate n-channel IGZO TFT with a shared common gate electrode. The fabricated vertically stacked complementary inverter exhibited full swing characteristics with a voltage gain of ~33.6, a high noise margin of 3.13 V, and a low noise margin of 3.16 V at a supplied voltage of 10 V. The achieved voltage gain of the fabricated complementary inverter was higher than that of the vertically stacked complementary inverters composed of other oxide TFTs in previous works. In addition, we showed that the vertically stacked complementary inverter exhibited excellent visible-light photoresponse. This indicates that the oxide TFT-based vertically stacked complementary inverter can be used as a sensitive photo-sensor operating in the visible spectral range with the voltage read-out scheme.

Biofouling is a persistent problem for desalination and water treatment membranes because it critically degrades membrane performance. Here, we report desalination membranes with ultrahigh biofouling resistance fabricated using a synergistic anti-biofouling strategy that combines topological and chemical antifouling modifications. Specifically, both the surface topology and the chemistry of desalination membranes were tailored by creating a biomimetic Sharklet pattern and integrating hydrophilic tannic acid and biocidal silver nanoparticles (AgNPs). The resultant membrane significantly enhanced biofouling resistance compared to the membranes modified by either the topological or chemical modifications alone due to the combinatorial antifouling effect. Importantly, the topological anti-biofouling effect was much more significant than the chemical effect under dynamic flow conditions due to the unique surface flows generated by the Sharklet geometry. Interestingly, the surface flow characteristics of the Sharklet pattern also effectively suppressed the leaching of the incorporated AgNPs and thus prolonged their anti-biofouling effect, highlighting the synergistic effect of the proposed combination strategy. This approach opens a new avenue for the fabrication of functional membranes, coatings and surfaces with superior antifouling and self-cleaning functions by elucidating the underlying antifouling mechanisms.

In this study, we investigated the effects of film thickness (tch) on the radiation damage of indium-gallium-tin oxide (IGTO) thin films and radiation tolerance of high-mobility IGTO thin-film transistors (TFTs). The radiation tolerance of the TFTs was evaluated using a 5-MeV proton beam at a fixed dose of 1013 cm−2. Using tch values of 12, 27, and 42 nm, the IGTO TFT with the 12-nm-thick channel layer exhibited the best electrical performance and radiation tolerance. The radiation tolerance significantly decreased as tch increased. To elucidate the mechanism responsible for the observed phenomena, the physical and chemical properties of the IGTO thin films with different values of tch were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy before and after the proton beam irradiation. The characterization results revealed that the decreased radiation tolerance of the thicker-channel IGTO TFTs were mainly attributed to the further enhanced oxygen vacancy generation due to the atomic displacement cascades within the IGTO channel layer after the proton irradiation. To the best of our knowledge, this is the first report studying the tch effects on the radiation hardness of oxide TFTs. The results of this study demonstrate that tch is a key parameter determining the radiation tolerance of oxide TFTs and a thin channel layer is advantageous in improving the radiation tolerance of oxide TFTs.

Sharkskin-mimetic (Sharklet) patterning has proven effective to enhance the fouling resistance of the surface. Herein, we systematically investigated the colloidal fouling behavior on the Sharklet-patterned polyurethane (PUA) surfaces with different pattern spacings (1.5, 2 and 6 µm) by performing both in-situ monitoring and lattice Boltzmann (LB) simulations. Our careful in-situ monitoring of the movement of polystyrene model foulant particles (0.9 µm diameter) revealed that varying the pattern spacing differentiated both the degree and local distribution of colloidal fouling on the Sharklet-patterned surface. Specifically, the 2 µm-spaced pattern exhibited the least fouling among three different spacing patterns. Furthermore, fouling was predominant in the periphery of each pattern unit for the 1.5 µm-spaced pattern, while it was most severe in the region between the neighboring protrusions for the 6 µm-spaced patterns. Interestingly, the LB simulation enabled the qualitative tracking of individual foulants on the Sharklet-patterned surface, which was consistent with the experimental observations. It suggested that the distribution of the deposited foulants is strongly related to the magnitude and direction of the local hydrodynamic force exerted on the foulants. Our proposed synergistic approach provides a new platform for the evaluation of the fouling behavior on patterned surfaces.

Here, we present a facile solvent activation method for significantly enhancing the desalination performance of reverse osmosis (RO) membranes. Polyamide (PA)-thin film composite (TFC) RO membranes were activated with a dimethyl sulfoxide (DMSO)/water mixture, whose solvency power was carefully controlled by adjusting the DMSO volume fraction. A DMSO/water mixture with a DMSO volume fraction of 0.3 effectively activated the PA selective layer while marginally deforming the polysulfone support of the lab-made PA-TFC membrane, thus considerably enhancing its water permeance by ~43% while maintaining its NaCl rejection (~99.4%). All the commercial membranes activated with the optimized DMSO/water activation protocol also exhibited dramatically enhanced water permeance (26–155%) with unchanged or even higher NaCl rejection, surpassing the conventional permeability–selectivity trade-off. A careful characterization of the structures and properties of the model PA film under various solvent environments revealed the thermodynamics and kinetics associated with the activation-induced structural deformation of the PA network, which governs its structural density, consequently affecting the separation properties of the membrane. Our strategy provides a commercially viable means for the fabrication of high-performance membranes together with shedding light on the underlying the structure-property relationship of polymeric membranes.

Quorum sensing inhibitors (QSIs) have shown promising results in reducing biofouling in various membrane systems. Vanillin was shown to inhibit QS of gram-negative bacteria during water treatment. Here, four vanillin-analogues with various chemical structures were used to understand the QS mechanisms in biofilm reduction and to compare direct dosing and surface modification of the inhibitors. Biofilm reduction, evaluated based on the content of extracellular polymeric substances (EPS), was the greatest with vanillin (49%) and occurred to some extent with 4-hydroxybenzaldehyde (21%) and m-anisaldehyde (13%), when direct dosing was applied. Experiments using vanillin-analogues revealed crucial roles of the chemical structure and functional groups on the inhibition of biofilm formation. The aldehyde and hydroxyl groups in both vanillin and 4-hydroxybenzaldehyde might be essential for QS inhibition. Further, surface modification with interfacial polymerization and immobilization of QSIs was conducted to evaluate their anti-biofouling capabilities. Surface modification was markedly effective in reducing biofilm formation; the EPS content of biofilms formed on vanillin-incorporated membranes was reduced by 64%. Additionally, the modified membranes showed a water flux comparable to that of pristine membranes, showing little possibility to block membrane pores during modification procedures. These findings will aid the development of QSI-based techniques for biofouling mitigation.

In this study, the effects of capping layers with different metals on the electrical performance and stability of p-channel SnO thin-film transistors (TFTs) were examined. Ni- or Pt-capped SnO TFTs exhibit a higher field-effect mobility (μFE), a lower subthreshold swing (SS), a positively shifted threshold voltage (VTH), and an improved negative-gate-bias-stress (NGBS) stability, as compared to pristine TFTs. In contrast, Al-capped SnO TFTs exhibit a lower μFE, higher SS, negatively shifted VTH, and degraded NGBS stability, as compared to pristine TFTs. No significant difference was observed between the electrical performance of the Cr-capped SnO TFT and that of the pristine SnO TFT. The obtained results were primarily explained based on the change in the back-channel potential of the SnO TFT that was caused by the difference in work functions between the SnO and various metals. This study shows that capping layers with different metals can be practically employed to modulate the electrical characteristics of p-channel SnO TFTs.

We utilized Ni as a floating capping layer in p-channel SnO thin-film transistors (TFTs) to improve their electrical performances. By utilizing the Ni as a floating capping layer, the p-channel SnO TFT showed enhanced mobility as high as 10.5 cm2·V−1·s−1. The increase in mobility was more significant as the length of Ni capping layer increased and the thickness of SnO active layer decreased. The observed phenomenon was possibly attributed to the changed vertical electric field distribution and increased hole concentration in the SnO channel by the floating Ni capping layer. Our experimental results demonstrate that incorporating the floating Ni capping layer on the channel layer is an effective method for increasing the field-effect mobility in p-channel SnO TFTs.

Organic solvent nanofiltration (OSN) has made significant advances recently, and it is now possible to fabricate thin film composite (TFC) membranes with a selective layer thickness below 10 nm that gives ultrafast solvent permeance. However, such high permeance is inadvertently limited by the support membrane beneath the selective layer, and thus there is an urgent need to develop a suitable support to maximize TFC performance. In this work, we employed a commercially available polyethylene (PE) battery separator as a porous support to fabricate high performance TFC OSN membranes. To deposit a uniform polyamide selective layer onto the porous support via interfacial polymerization, the PE support was hydrophilized with O2 plasma and the reaction efficiency was optimized using a surfactant. Owing to the high surface porosity of the PE support and the high permselectivity of the PA layer, the PE-supported TFC membrane outperformed the previously reported OSN membranes and its performance exceeded the current performance upper bound. A solvent activation step dramatically improved the solvent permeance by 5-fold while maintaining nanoseparation properties. In addition to the superior OSN performance, the commercial availability of the PE support and simplified TFC fabrication protocol would make the PE-supported OSN membranes commercially attractive.

Controlling biofouling is critical for membrane materials exposed to aquatic environments. Specifically, the sharkskin-mimetic, so-called Sharklet, surface pattern has proven effective for suppressing biofilm formation on desalination membranes. In this study, a series of Sharklet patterns with different unit and pattern spacings were designed on reverse osmosis (RO) membrane surfaces to identify the effect of the Sharklet pattern dimension on membrane biofouling. A high fidelity of Sharklet-patterned RO membranes with different spacing dimensions were successfully fabricated by micromolding combined with layered interfacial polymerization. The biofouling behavior of the fabricated Sharklet-patterned RO membranes was systematically characterized under both static and dynamic conditions. Importantly, dynamic biofouling results showed that the anti-biofouling effect of the Sharklet pattern was optimized when the unit and pattern spacings were both 2 μm. Computational fluid dynamics simulation elucidated the surface flow characteristics of the Sharklet patterns depending on the spacing dimensions. The maximized anti-biofouling performance of the Sharklet pattern with 2 μm spacings was hypothesized to be determined by the balance between the intrinsic biofouling propensity (under static conditions) and surface flow characteristics such as vortex and primary/secondary flows (under dynamic conditions).

We present a facile method for fabricating polyamide (PA) nanofiltration (NF) membranes exhibiting remarkable separation performance and high acid stability via solvent activation on PA reverse osmosis (RO) membranes with strong polar aprotic solvents (dimethyl sulfoxide (DMSO), dimethylformamide and N-methyl-2-pyrrolidone). The solvents with strong solvency power for PA greatly swelled and deformed the dense RO PA layer, making the PA network more permeable and looser, which significantly improved the water permeance of the RO membrane while maintaining its high rejection to divalent salts. Consequently, the solvent-activated RO membranes exhibited remarkable NF-grade separation performance, exceeding that of the commercial NF membrane (NF270, Dow Filmtec.). Particularly, the DMSO-activated membrane showed ∼30% higher water permeance, higher salt rejection and ∼6.8 times higher monovalent/divalent ion selectivity than NF270. This was attributed to the strongest solvency power of DMSO among the solvents used. Moreover, the solvent-activated membrane exhibited the superior acid stability to NF270 owing to the higher acid resistance of its fully-aromatic PA chemistry than that of the semi-aromatic PA. Our proposed method is a simple, effective and commercially viable strategy for fabricating high-performance and acid-resistant NF membranes that can expand the application spectrum of NF technology.

Eleutherococcus senticosus (Araliaceae) is immunological modulator which has been successfully used for anti-inflammatory effectors on anti-rheumatic diseases in oriental medicine. Mitogen-activated protein kinases (MAPKs) and Akt modulate the transcription of many genes involved in the inflammatory process. In this study, we investigated the inhibitory effects of Eleutherococcus senticosus on the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharides (LPS)-activated macrophages. Finally, we studied the involvement of MAPKs and Akt signaling in the protective effect of Eleutherococcus senticosus in LPS-activated macrophages. Eleutherococcus senticosus significantly attenuated LPS-induced iNOS expression but not COX-2 expression. In using the standard inhibitors (MAPKs and Akt), our results show that Eleutherococcus senticosus downregulates inflammatory iNOS expression by blocking JNK and Akt activation.

Purpose: To report a case of the Heidenhain variant of sporadic Creutzfeldt-Jakob disease (CJD), predominantly characterized by visual impairment at onset. Case summary: History-taking, ophthalmologic examination, neurologic examination, cerebrospinal fluid examination including 14-3-3 protein analysis, and brain MRI were performed in a 48-year-old man with progressive visual loss and a visual field defect. These symptoms were accompanied by visual illusion and macropsia. Neurologic examination revealed relatively rapidly progressing cognitive impairment, ataxia, aphasia, and myoclonus. The 14-3-3 protein was detectable in otherwise normal CSF samples. The diffusion weighted brain MRI showed increased signal intensity in both occipital lobes, the basal ganglia, the temporal and frontal lobes. He was clinically diagnosed as having a Heidenhain variant of sporadic CJD. Conclusions: In a patient with a rapidly progressive visual loss, visual field defects, visual illusion, and neurologic abnormalities including progressive dementia, ataxia, aphasia, and myoclonus, the Heidenhain variant of CJD should be considered. Because prions, a cause of CJD, exhibit unusual resistance to conventional chemical and physical decontamination methods, it is necessary to have an appropriate management scheme to prevent the spread of infection.