Direct Transport Research Articles

Light-Triggered Droplet Gating Strategy Based on Janus Membrane Fabricated by Femtosecond Laser.

The characteristics of the directed transport of liquids based on Janus membranes play a crucial role in practical applications in energy, materials, physics, chemistry, medicine, biology, and other fields. Although extensive progress has been made, it is still difficult to realize the accurate controllability of liquid directional transmembrane transport. The current gating strategies for the directed transport of liquids based on Janus membranes still have some limitations: (a) using magnetic fluid may cause contamination due to the addition of new substances and (b) utilizing hydrophobicity/hydrophilicity conversion of titanium dioxide requires a long switching time (over 30 min). Herein, a strategy is proposed to precisely control liquid directional transport by altering the wettability of droplets on Janus films prepared by a femtosecond laser through photothermal effects. Infrared laser irradiation on Janus film coated with CNTs can effectively convert light energy into thermal energy, rapidly increase the surface temperature of Janus film, and change the wettability of the liquid on the film. Liquid transmembrane directional transport can be achieved within a few seconds without contaminating the transported liquid. The proposed gating strategy can enable the application of Janus membranes in various scenarios such as microchemical reactions, biological cell culture, and interface self-propulsion.

Creeping Stem 1 regulates directional auxin transport for lodging resistance in soybean.

Soybean, a staple crop on a global scale, frequently encounters challenges due to lodging under high planting densities, which results in significant yield losses. Despite extensive research, the fundamental genetic mechanisms governing lodging resistance in soybeans remain elusive. In this study, we identify and characterize the Creeping Stem 1 (CS1) gene, which plays a crucial role in conferring lodging resistance in soybeans. The CS1 gene encodes a HEAT-repeat protein that modulates hypocotyl gravitropism by regulating amyloplast sedimentation. Functional analysis reveals that the loss of CS1 activity disrupts polar auxin transport, vascular bundle development and the biosynthesis of cellulose and lignin, ultimately leading to premature lodging and aberrant root development. Conversely, increasing CS1 expression significantly enhances lodging resistance and improves yield under conditions of high planting density. Our findings shed light on the genetic mechanisms that underlie lodging resistance in soybeans and highlight the potential of CS1 as a valuable target for genetic engineering to improve crop lodging resistance and yield.

Complementary Superwetting Structures Treated by a Femtosecond Laser for Simultaneous Spontaneous Directional Transport of Water Droplets and Underwater Bubbles.

The control of fluid transport is crucial and has broad applications in the fields of intelligent systems and microfluidics. However, current studies usually focus on the spontaneous directional transport of a single type of fluid or require complex preparation processes. In this paper, the single femtosecond laser direct processing of complementary superwetting structures using polyimide/polytetrafluoroethylene is proposed, for the first time, to realize simultaneous spontaneous directional transport of water droplets and underwater bubbles without any additional energy or chemical treatment. The flexible laser fabrication enables the creation of diverse transport structures, facilitating the achievement of linear and curvilinear fluid transport on superwetting structures. In addition, relevant applications in self-transporting chemical reactions and bubble switching are presented. This technique provides a novel approach to fabricate patterned superwetting surfaces for applications in intelligent transport, microbiology, and chemistry.

Potential Reduction in Carbon Emissions in the Transport of Aggregates by Switching from Road-Only Transport to an Intermodal Rail/Road System

Aggregates are the second-most consumed product in the world after water. This geological resource is used as building and construction material, and its production in quarries and delivery to customers generates several environmental problems. Their transport from quarries to consumption points, almost entirely done by truck, also generates impacts such as an increase in traffic and noise and the emission of greenhouse gases and other pollutants. Transportation and storage of goods account for 15% of greenhouse gas emissions in Europe and will increase significantly by 2050. To mitigate this, the European Union suggested shifting 30% of long-distance road freight to cleaner alternatives, such as rail or waterborne transport. This approach neglects the enormous volume of short-distance freight movement and its impact on achieving the goal of reducing greenhouse gas emissions. In this study, the hypothesis to test is whether the use of an intermodal rail/road transport mode, instead of just roads, for the transport of some products can help reduce global CO2 emissions even for short distances. To test this, this study investigates the carbon emissions (and transport cost reduction) generated by rail/road intermodal aggregate transport for short distances in the Madrid region (Spain), rather than the currently used direct truck transport. An analysis of variables, such as aggregate supply, demand locations and amounts, and road and rail networks, using a geographical information system provides the associated carbon emissions of the different transport alternatives. To obtain a reduction in CO2 emissions, this study proposes the establishment of intermodal transfer facilities near consumption centers, where materials are primarily transported by rail, with road transport limited to the final delivery to consumption areas. The results anticipate a notable decrease in carbon emissions in aggregate transport and allow the establishment of more efficient and environmentally friendly rail/road intermodal transport that would help to meet the goals of reducing climate change while making the use of aggregates more environmentally friendly.

Choroid plexus extracellular vesicle transport of blood-borne insulin-like growth factor 1 to the hippocampus of the immature brain

Abstract Reduced serum level of insulin-like growth factor 1 (IGF-1), a major regulator of perinatal development, in extremely preterm infants has been shown to be associated with neurodevelopmental impairment. To clarify the mechanism of IGF-1 transport at the blood-cerebrospinal fluid (CSF) barrier of the immature brain, we combined studies of in vivo preterm piglet and rabbit models with an in vitro transwell cell culture model of neonatal primary murine choroid plexus epithelial (ChPE) cells. We identified IGF-1 positive intracellular vesicles in ChPE cells and provided data indicating a directional transport of IGF-1 from the basolateral to the apical media in extracellular vesicles (EVs). Exposure of the ChPE cells to human IGF-1 on the basolateral side increased the secretion of IGF-1 positive EVs in the apical media. Mass spectrometry analysis displayed similarities in protein content between EVs derived from preterm piglet CSF and ChPE derived EVs. Furthermore, exposure of ChPE cells to human IGF-1 caused an enrichment of human IGF-1 and transmembrane p24 trafficking protein 2, proteins important for perinatal development, in apical media derived EVs. Moreover, intraventricular injections of ChPE cell-derived EVs in preterm rabbit pups resulted in an uptake of EVs in the brain, displaying penetration through the ependymal lining and deep into the hippocampus. Finally, exposure of rat hippocampus neurons to ChPE cell derived EVs resulted in internalization of the EVs in hippocampal soma and neurites. In summary, we describe a transport pathway for blood-borne IGF-1 in EVs, through the blood–CSF barrier to the hippocampus in the immature brain.

Cilia‐Inspired Functional Channels for High‐Speed and Directional PEMFC Drainage

AbstractProton Exchange Membrane Fuel Cells (PEMFC) consist of channels that require efficient drainage for optimum performance. However, it remains a grand challenge to achieve both directed and high‐speed active drainage in PEMFC channels. This greatly limits current PEMFC performance. Herein, inspired by respiratory cilia, a bioinspired structural design strategy is introduced into the channel surface to significantly enhance its active droplet transport efficiency. Two artificial cilia arrays are fabricated and named as plane‐bottom artificial cilia array (PACA) and concave‐bottom artificial cilia array (CACA) according to their respective shapes. PACA demonstrates stable directional transport. The droplet speed reaches as high as 86 mm s−1 with droplet volumes ranging from 10 to 20 µL. This is surpassed by CACA. Its speed reaches as high as 163 mm s−1 for droplet volumes ranging from 10 to 50 µL. PEMFC experimental evaluation of diameter sizes shows that CACA can be tuned for enhancing its electrochemical performance. CACA‐8 achieves the maximum power density (0.5339 W cm−2) at 1.1864 A cm−2, representing an 18.70% increase compared to conventional PEMFC channels. This work provides a promising strategy for the stable and efficient transport of liquid water in PEMFC.

Origin of the Difference in Proton Transport Direction between Inward and Outward Proton-Pumping Rhodopsins.

ConspectusActive transport is a vital and ubiquitous process in biological phenomena. Ion-pumping rhodopsins are light-driven active ion transporters that share a heptahelical transmembrane structural scaffold in which the all-trans retinal chromophore is covalently bonded through a Schiff base to a conserved lysine residue in the seventh transmembrane helix. Bacteriorhodopsin from Halobacterium salinarum was the first ion-pumping rhodopsin to be discovered and was identified as an outward proton-pumping rhodopsin. Since the discovery of bacteriorhodopsin in 1971, many more ion-pumping rhodopsins have been isolated from diverse microorganisms spanning three domains (bacteria, archaea, and eukaryotes) and giant viruses. In addition to proton-pumping rhodopsins, chloride ion- and sodium ion-pumping rhodopsins have also been discovered. Furthermore, diversity of ion-pumping rhodopsins was found in the direction of ion transport; i.e., rhodopsins that pump protons inward have recently been discovered. Very intriguingly, the inward proton-pumping rhodopsins share structural features and many conserved key residues with the outward proton-pumping rhodopsins. However, a central question remains unchanged despite the increasing variety: how and why do the ion-pumping rhodopsins undergo interlocking conformational changes that allow unidirectional ion transfer within proteins? In this regard, it is an effective strategy to compare the structures and their evolutions in the proton-pumping processes of both inward and outward proton-pumping rhodopsins because the comparison sheds light on key elements for the unidirectional proton transport. We elucidated the proton-pumping mechanism of the inward and outward proton-pumping rhodopsins by time-resolved resonance Raman spectroscopy, a powerful technique for tracking the structural evolutions of proteins at work that are otherwise inaccessible.In this Account, we primarily review our endeavors in the elucidation of the proton-pumping mechanisms and determination factors for the transport directions of inward and outward proton-pumping rhodopsins. We begin with a brief summary of previous findings on outward proton-pumping rhodopsins revealed by vibrational spectroscopy. Next, we provide insights into the mechanism of inward proton-pumping rhodopsins, schizorhodopsins, obtained in our studies. Time-resolved resonance Raman spectroscopy provided valuable information about the structures of the retinal chromophore in the unphotolyzed state and intermediates of schizorhodopsins. As we ventured further into our investigations, we succeeded in uncovering the factors determining the directions of proton release and uptake in the retinal Schiff base. While it is intriguing that the proton-pumping rhodopsins actively transport protons against a concentration gradient, it is even more curious that proteins with structural similarities transport protons in opposite directions. Solving the second mystery led to solving the first. When we considered our findings, we realized that we would probably not have been able to elucidate the mechanism if we had studied only the outward pump. Our Account concludes by outlining future opportunities and challenges in the growing research field of ion-pumping rhodopsins, with a particular emphasis on elucidating their sequence-structure-function relationships. We aim to inspire further advances toward the understanding and creation of light-driven active ion transporters.

Nanoarchitecture via Synchronic Stacking of Metallic and Nonmetallic Two-Dimensional Nanosheets for Optimal Light-Driven Ion Transport.

The exceptional selectivity and responsive ion transport in biological channels inspire technology breakthrough in energy, environmental, and resource sectors. However, existing nanofluidic systems with a high photothermal conversion efficiency often exhibit excessive thermal conductivity, which impedes the creation of effective temperature gradients and results in a low ion transport efficiency. In this study, a strategy based on the synchronic stacking of metallic and nonmetallic two-dimensional (2D) nanosheets was presented to construct heterogeneous nanofluidic channels. This specific nanoconfined architecture sustained high temperatures in the illuminated area while maintaining low temperatures in the nonilluminated area, thus obtaining a robust driving force from sunlight for directional ion transport. As a result, our light-responsive ion transport system demonstrated significant potential in solar energy conversion and osmotic energy harvesting, surpassing those of all previously reported nanofluidic systems. Additionally, although it is still at the proof-of-concept stage, it shows great promise in light signal monitoring. This work provides an effective strategy for developing advanced light-responsive ion transport systems and their important applications.

Analysis of Downstream Sediment Transport Trends Based on In Situ Data and Numerical Simulation

This study conducted an in-depth analysis of the sediment dynamics in the lower reaches of the Changhua River and its estuary on Hainan Island. Through field collection of topographic data and sediment sampling, combined with advanced computational techniques, the study explored the transport pathways and depositional patterns of sediments. The grain size trend analysis (GSTA) method was utilized, in conjunction with the Flemming triangle diagram method, to classify the dynamic environment of the sediments. Furthermore, hydrodynamic modeling results were integrated to further analyze the transport trends of the sediments. The study revealed that the sediment types in the research area are complex, primarily consisting of gravelly sand and sandy gravel, indicating a generally coarse sedimentary environment in the region. The sediments in the lower reaches of the Changhua River generally transport towards the south and southwest (in the direction of Beili Bay). The net sediment transport directions inferred from the GSTA model are largely consistent with the Eulerian residual flow patterns, especially in the offshore area, where discrepancies are observed in the nearshore zone. The nearshore transport is influenced by the combined effects of alongshore currents, residual flows, and river inputs, while the offshore transport exhibits a shift from the northwest to southwest directions, reflecting the regional circulation patterns.

Uphill directional passive transport of water droplets on axisymmetric surfaces

Spontaneous directional transport of droplets by a surface curvature gradient, adopted by many biological species such as cactus and sand moss, is particularly suitable for applications including anti-icing, self-cleaning, and water harvesting, which eliminates the need for external energy input. However, this directional droplet transport is limited to short transport distance and no maneuverability, i.e., droplets can only migrate toward a flatter region and gradually stop. Fixed structures that can regulate droplet movement, if they could be created, would significantly advance their applications in a variety of areas. In this work, we propose a method to regulate the spontaneous motion of droplets on solid surfaces using surface curvature gradients. Molecular dynamics simulations show that droplets on general bowl-shaped axisymmetric surfaces can travel in the uphill direction (from the base to the apex) and move continuously to the apex with almost a constant speed. The mechanisms governing opposite directional transport of droplets are explained, and the conditions required to guarantee the transport in the reversed direction are discussed.

3D-printed Bio-inspired porous electrode by bidirectional enhancement strategy with high mass loading and enhanced energy density for supercapacitors

The effective strategy for increasing areal capacity involves the use of 3D printed thick-electrode with high mass loading. However, thick-electrode still encounters challenges such as incomplete electrolyte penetration and slow ion transport. Here, we successfully prepared lignocellulosic nanofibrils (LCNFs) from abundant bamboo biomass and developed functional ink composed of LCNFs/ carbon nanotubes (CNTs) / polyaniline (PANI) / polyvinyl alcohol (PVA) for printing. An innovative 3D printing bidirectional enhancement strategy was proposed to increase the mass loading of active materials in the vertical direction and construct ion transport channels in the transverse direction. The biomimetic porous N-doped electrode obtained after annealing treatment exhibits a more continuous conductive network, larger surface area, higher utilization of active materials, and smoother ion transport pathways compared to thick-electrode. Therefore, the Triangles biomimetic electrode exhibits an enhanced areal/specific capacitance compared to thick-electrode, reaching 5.30F·cm−2 (184.03F·g−1) and 4.40F·cm−2 (122.22F·g−1) at 2 mA·cm−2, respectively. The symmetric device demonstrates an areal capacitance of 1.34F·cm−2 at 1 mA·cm−2 and achieves an energy density of 0.186 mWh·cm−2 at a power density of 0.49 mW·cm−2. The work provides valuable insights into the design of electrode structures for high-performance supercapacitors.

Segmental-porosity regulation of nanochannel membranes with anomalously improved ion selectivity for enhanced osmotic power generation

Nanochannel-based osmotic energy conversion can directly convert salinity gradient energy between solutions with different ion concentrations into electric energy. In the energy conversion process, the high-concentration side of the nanochannel membrane has high ion permeability but low ion selectivity, whereas the low-concentration side exhibits opposite properties, which is the inherent limitation of osmotic power. However, the relationship between ion selectivity and permeability is unclear, which hinders the improvement of the output power density. This paper reports a segmental-porosity regulation method to break through the inherent constraints of the ion selectivity–permeability trade-off. The nanochannel membrane was divided into three regions along the ion transport direction as upstream, midstream, and downstream. The porosities of these three regions were separately regulated to optimize the structures for ion selectivity–permeability matching. When a high porosity was adopted for the downstream region and a small and mediate porosity combination was used for the upstream and midstream regions, the highest output power density was achieved, which was 78.44% higher than that of a straight nanochannel with homogeneous porosity under a 100-fold concentration ratio. The outstanding osmotic power generation performance of the optimized segmental structure was attributed to the alleviated ion concentration polarization and unexpectedly improved ion selectivity. Finally, the process and underlying mechanisms of segmental-porosity regulation are also proposed. This paper reports a novel methodology for designing the structure and porosity of nanochannel membranes to enhance osmotic power generation.

Proton direct transport channels incorporated with protonated porphyrin hyper-crosslinked structures for high proton conductivity HT-PEMs

The trade-off between the mechanical properties and proton conductivity of phosphoric acid (PA)-doped polybenzimidazole (PBI) membranes presents a significant challenge to their development and practical application as high-temperature proton exchange membranes (HT-PEMs). In this study, we prepared hyper-crosslinked poly[2,2′-(p-oxydiphenylene)-5,5′-benzimidazole] (OPBI) membranes with porphyrins (TBPP) containing a substantial amount of halogen. The combination of the protonation effect of porphyrin and the support of the hyper-crosslinked structure results in TBPP-OPBI crosslinked membranes exhibiting excellent mechanical strength and proton conductivity at high PA doping levels (ADLs). In particular, the TBPP-15-OPBI crosslinked membrane exhibits high proton conductivity of 244 mS cm−1 at 180 °C, which is 3.64 times greater than that observed in the OPBI membrane. The H2/air fuel cells based on the TBPP-15-OPBI crosslinked membranes exhibit a peak power density of 521.1 mW cm−2 at 160 °C without humidification and back pressure, as well as excellent durability (over 100 h). Thus, this work provides a straightforward and feasible structural design approach to comprehensively enhance the performance of PA-PBI proton exchange membranes.

Unveiling the potential of intranasal delivery of renin-angiotensin system drugs: Insights on the pharmacokinetics of irbesartan

The therapeutic interest of renin-angiotensin system (RAS) drugs for the treatment of neuroinflammation has been recently acknowledged. Nevertheless, most RAS drugs display limited passage across the blood–brain barrier (BBB). Therefore, this study investigated the potential of intranasal (IN) delivery of six RAS drugs to circumvent the BBB and attain the brain, envisioning its future use in central nervous system (CNS) neuroinflammatory diseases, such as Alzheimer’s disease (AD).Captopril, enalaprilat, irbesartan, lisinopril, losartan and valsartan were firstly screened based on their impact on the viability of nasal, lung, and neuronal cell lines and their apparent permeability (Papp) across porcine olfactory mucosa. Irbesartan, identified as the one with the best safety and permeability balance, was selected for pharmacokinetic characterization following single and multidose IN administration to CD-1 mice. The results were compared to those obtained by intravenous (IV) injection to assess direct nose-to-brain drug delivery. Olfactory toxicity and anxiety were also evaluated after multidose IN treatment.Irbesartan IN administration significantly enhanced brain targeting, with a 3-fold increase in the maximum concentration (Cmax) and a 2.5-fold increase in the area under the curve (AUCt) in the brain compared to IV route. The drug exhibited a tmax of 15 min post-IN administration and achieved a brain targeting efficiency of 239.56%, with a significant direct transport percentage of 58.26%. Multidose administration indicated no systemic or tissue accumulation, with accumulation ratio (Rac) values below 1.0, and no significant olfactory toxicity.Overall, the study highlights the potential of IN delivery of irbesartan as a promising strategy to improve brain targeting and therapeutic outcomes in CNS diseases such as AD, providing an effective approach to bypass BBB limitations.

Design Formulation of Nanospanlastic Novel Carriers as a Promising Approach to Enhanced Bioavailability in Intranasal Drug Delivery for Sinusitis: Statistical Optimization and In vitro and In vivo Characterization

Background: Most new biologically active chemicals require better water solubility and slower dissolution rates. Cefdinir (CFD) has a very low bioavailability in its crystalline form and is poorly soluble in water. Objective: By preparing cefdinir's spanlastic nanovesicles (SNVs) using the ethanol injection method, the current study has attempted to enhance the drug's solubility and bioavailability using a statistical design approach. Methods: Independent variables, including the nonionic surfactant concentration, edge activator (EA), sonication time, SNVs entrapment efficiency, particle size, zeta potential, PDI, and in vitro release, have been evaluated. The best CFD-SNVs were positioned within in situ gel with muco-adhesive properties made of hydroxypropyl methylcellulose and deacetylated gellan gum. By contrasting intranasal injection of the produced gel with an IV solution, animal models have been used to investigate CFD's systemic and cerebral dynamics. Results: Statistical analysis has suggested an ideal SNVs formulation with nonionic surfactant (65 mg), EA (15 mg), and sonication (3 min). The sol-gel temperature for forming the mucoad-hesive in situ gel containing SNVs has been found to be 34.03°C, and 18.36 minutes has been the extended mucociliary transit time. Following intranasal injection, compared to SNV dispersion, the gelling system has exhibited higher brain bioavailability (2251.9 ± 75 vs. 5281.6 ± 51%, re-spectively). The gel has also demonstrated effective drug targeting of the brain with higher direct transport percentage indices. Conclusion: Mucoadhesive in situ gel with CFD-loaded SNVs can be administered via the in-tranasal route. To enhance bioavailability in the brain and drug targeting from the nose to the brain, nasal in situ gel loaded with CFD-SNVs could be a new carrier to be employed in sinusitis.

A diode-like integrated hydrogel for piezoionic generators and sensors

Wearable sensing electronic devices based on hydrogel are gradually developing towards multifunction and portability, however, efficiently harvesting energy from the surrounding environment to power traditional hydrogel-based wearable electronic devices is a major challenge. The assembly of multilayer heterogeneous hydrogels is a potential strategy to address this challenge. Herein, inspired by the structure of diodes, a diode-like integrated hydrogel composed of a three-tier structure of anionic polyelectrolyte hydrogel, polyacrylamide hydrogel and cationic polyelectrolyte hydrogel is developed. By the connection of polyacrylamide hydrogel, the composite hydrogel exhibits excellent structural stability and mechanical properties. Notably, due to the introduction of MXene ion-conducting microchannels, the directional transport of free cations and anions ionized by anionic and cationic polyelectrolytes is achieved, thereby improving the conductivity (74.58 mS/cm), sensing (gauge factor = 7.47) and piezoionic output performance of the composite hydrogel. The composite hydrogel-based sensor can sense tiny facial movements and recognize the direction of human movement, and the composite hydrogel-based piezoionic generator exhibit more efficient mechanical-electric conversion performance, which can output the maximum voltage of 1410mV, current of 28 μA, and power density of 2.9mW/m2 for a composite hydrogel of 5×5 cm2. The integration of multilayer heterogeneous hydrogels proposes a versatile strategy for the development of high-performance hydrogel-based self-powered sensing electronic devices, expanding the application of hydrogels in artificial intelligence and human-computer interaction.

Diurnal Cycles of Cloud Properties and Precipitation Patterns over the Northeastern Tibetan Plateau During Summer

In the context of rising temperatures and increasing humidity in Northwest China, substantial gaps remain in understanding the mechanisms of land–atmosphere cloud–precipitation coupling across the northeastern Tibetan Plateau (TP), Loess Plateau (LP), and Huangshui Valley (HV). This study addresses these gaps by investigating cloud properties and precipitation patterns utilizing the Fengyun-4 Satellite Quantitative Precipitation Estimation Product (FY4A-QPE) and ERA5 datasets. We specifically focus on Lanzhou, a pivotal city within the LP, and Xining, which epitomizes the HV. Our findings reveal that diurnal variations in precipitation are significantly less pronounced in the eastern regions compared to northeastern TP. This discrepancy is attributed to marked diurnal fluctuations in convective available potential energy (CAPE) and wind shear between 200 and 500 hPa. While both cities share similar wind shear patterns and moisture transport directions, Xining benefits from enhanced snowmelt and effective water retention in surrounding mountains, resulting in higher precipitation levels. Conversely, Lanzhou suffers from moisture deficits, with dry, hot winds exacerbating the situation. Notably, precipitation in Xining is strongly correlated with CAPE, influenced by diurnal variability, and intensified by valley and lake–land breezes, which drive afternoon convection. In contrast, Lanzhou’s precipitation exhibits a weak relationship with CAPE, as even elevated values fail to generate significant cloud formation due to insufficient moisture. The ongoing trends of warming and humidification may lead to improved precipitation patterns, especially in the HV, with potential ecological benefits. However, concentrated rainfall during summer afternoons and midnights raises concerns regarding extreme weather events, highlighting the susceptibility of the HV to geological hazards. This research underscores the need to further explore the uncertainties inherent in precipitation dynamics in these regions.

A 3D-Printed Bionic Membrane with Autonomously Passive Unidirectional Liquid Transfer Capability for Water Condensation, Collection, and Purification.

Interfacial solar vapor generation is a promising technology for alleviating the current global water crisis, and the evaporation rate and efficiency have approached the theoretical limit. In a practical interfacial evaporation water purification system, the collection rate of purified water is typically lower than the evaporation rate. Passive collection devices based on gravity are susceptible to environmental influences and exhibit low collection efficiency, while active collection devices consuming external energy suffer from complex device systems and extra energy consumption. Given that both collection devices are nonselective and unable to distinguish contaminants mixed in the vapor, bionic membranes with autonomously passive and unidirectional water transfer capacity are developed through 3D printing for efficient water collection. More importantly, the bionic membranes are capable of high-speed water transportation without the need for external energy or gravity drive and liquid-selective transportation for separating oily pollutants from the collected products. The directional transport property facilitates the modular assembly of the bionic membrane, extending its application to practical large-scale solar-driven seawater desalination systems.

Shoreline Behavior in Response to Coastal Structures: A Case Study in Haikou Bay, China

The rapid development of coastal structures on sandy coastlines raises concerns about their impacts on the shoreline’s evolution and the sediment transport dynamics. This study utilized a numerical modeling approach to simulate the multi-year response of Haikou Bay’s coastline to various nearshore structures, including piers and a large artificial island. The LITLINE module of the MIKE21 (v2020) software was employed to analyze the sediment transport patterns across three distinct coastal segments. The simulation results indicated that the sediment transport directions varied significantly: from west to east in the western segment, from east to west in the middle segment, and convergence toward the center in the eastern segment, divided by a construction trestle. The net sediment transport rates were quantified as 2000 m3/year for the western segment, 8000 m3/year for the middle segment, and 13,000 m3/year (west) and 10,000 m3/year (east) for the eastern segment. Due to the conflicting sediment transport directions on each side of the breakwater, noticeable deposition occurred on both sides. The presence of the artificial island created notable deposition in its wave shadow area, while the overall impact on the shoreline changes diminished over time. These findings underscore the significant influence of human activities, particularly coastal structures, on the natural evolution of shorelines.

Multilevel analysis of factors affecting the interhospital transfer of high-acuity pediatric patients: a focus on severe pediatric emergency patients

Purpose: The authors aimed to identify the factors affecting interhospital transfer (“transfer”) of severe pediatric patients who visited to an emergency department (ED).Methods: Using the Korean National ED Information System, we analyzed high-acuity patients aged 18 years or younger who visited EDs of local or regional emergency centers nationwide. The high acuity was defined as a Korean Triage and Acuity Scale 1-2. To investigate the factors associated with transfer, a multilevel modeling was selected, examining independent variables at both individual- and hospital-levels with transfer as a dependent variable.Results: A model consisting of variables at individual- and hospital-levels showed the factors as follows: mode of arrival(self-transport: odds ratio, 0.48 [95% confidence interval, 0.38-0.61]; other ambulances: 0.41 [0.24-0.71]; compared with firehouse ambulance), visit at 18:00-07:59 (0.75 [0.64-0.88]), intentional injury (1.59 [1.03-2.47]; compared with non-injury), decreased level of consciousness (drowsy: 1.94 [1.33-2.84]; stupor: 4.08 [2.99-5.57]; coma: 1.81 [1.26-2.60]; compared with alert), severe illness diagnosis (1.49 [1.12-1.98]), the number of all beds in EDs (1.02 [1.01-1.04]), and acceptance for treatment (0.92 [0.87-0.98]; with increment of 1%).Conclusion: This study confirms that both individual-level and hospital-level factors affect the transfer risk of severe pediatric patients in EDs. The study suggests the needs for direct transportation to specialized pediatric treatment facilities, and concentrated support for the pediatric emergency medical centers and pediatric trauma centers.