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Deciphering the dynamics of water transport across bronchial epithelial cell monolayers is pivotal for unraveling respiratory physiology and pathology. In this study, we employ an advanced microfluidic system to explore bidirectional water transport across 16HBE14σ bronchial epithelial cells. Previous experiments unveiled electroneutral multiple ion transport, with chloride ions utilizing transcellular pathways and sodium ions navigating both paracellular and transcellular routes. Unexpectedly, under isoosmotic conditions, rapid bidirectional movement of Na+ and Cl− was observed, leading to the hypothesis of a substantial transport of isoosmotic solution (145 mM NaCl) across cell monolayers. To validate this conjecture, we introduce an innovative microfluidic device, offering a 500-fold sensitivity improvement in quantifying fluid flow. This system enables the direct measurement of minuscule fluid volumes traversing cell monolayers with unprecedented precision. Our results challenge conventional models, indicating a self-regulating mechanism governing water transport that involves the CFTR channel and anion exchangers. In healthy subjects, equilibrium is achieved at an apical potential of Δφap = −30 mV, while subjects with cystic fibrosis exhibit modulation by an anion exchanger, reaching equilibrium at [Cl] = 67 mM in the airway surface liquid. This nuanced electrochemical basis for bidirectional water transport in bronchial epithelia sheds light on physiological intricacies and introduces a novel perspective for understanding respiratory conditions.

Introduction. The manufacturers currently develop new locomotives considering operating conditions with further locomotive fixation on the target ground. They also calculate the operational locomotive models with the key indicators for assessing the cost of the life cycle during the engineering stage. Therefore, the basic information for making operational decisions on purchase about selected locomotive items is the evaluation of the traction rolling stock effectiveness. The manufacturers of other vehicle types have similar aims in terms of operating conditions, engineering features, etc.Materials and methods. The scientists succeed in the usage of the modern evaluating approaches to the vehicles efficiency. The application of the similar criteria that differ in the calculation mechanism and the initial data volume is especially important in evaluating the effectiveness of the multimodal transportation of freight and passenger traffic. The article presented the critical analysis of the main approaches to assessing the effectiveness of the road, water and railway vehicles. Thus, the authors concluded that the manufacturers should consider both the efficiency of the vehicle and the usage intensity.Results. The authors demonstrate quantitative estimates of the proposed efficiency criterion for certificate features and considering real operational conditions. The paper presents the simulation results comparison with the calculation ones considering certificate features. Thus, operational conditions significantly effect the efficiency criterion.Discussion and conclusion. The authors highlight that the obtained results are universal for evaluating the effectiveness of the various vehicles in terms of different rolling stock features.

Background and Aims Allometric scaling between stomata and xylem for terrestrial woody plants is a widely observed pattern that may be constrained by water transport. Floating-leaved plants, a particular life form of aquatic plants, have leaves in direct contact with both air and water and a poorly developed xylem that may not be limited by water supply as for terrestrial plants. However, whether such an allometric scaling relationship still exists in floating-leaved plants has not been explored. Methods We analysed 31 floating-leaved species/varieties with a range in leaf area covering six orders of magnitude. For all 31 floating-leaved plants, we studied the allometric relationships between leaf area and petiole transverse area, and between total stomatal area and petiole vascular area. Key Results The slopes of both relationships were similar to the slope of the allometric relationship (1.23) between total stomatal area and xylem area of 53 terrestrial plants. However, for ten of them with xylem that can be clearly defined, the strong positive relationship between total stomatal area and petiole xylem area had a significantly smaller slope than that of terrestrial plants (0.64 vs. 1.23). Furthermore, after considering phylogeny, the scaling relationships between total stomatal area and petiole traits in floating-leaved plants remained significant. Conclusions We speculated that for floating-leaved plants, the hyperallometric relationship (slope >1) between the construction of leaf/stoma and petiole was promoted by the high demand for photosynthesis and thus more leaves/stomata. While the hypoallometric relationship (slope <1) between stomatal and xylem area was related more to hydraulic processes, the selection pressure on stomata was lower than xylem of floating-leaved plants. Allometric relationships among the hydraulic traits on water transport of aquatic plants are the result of natural selection to achieve maximum carbon gain, which is similar to terrestrial plants. [ABSTRACT FROM AUTHOR]

Summary: The hydraulic system of vascular plants and its integrity is essential for plant survival. To transport water under tension, the walls of xylem conduits must approximate rigid pipes. Against this expectation, conduit deformation has been reported in the leaves of a few species and hypothesized to function as a 'circuit breaker' against embolism. Experimental evidence is lacking, and its generality is unknown.We demonstrated the role of conduit deformation in protecting the upstream xylem from embolism through experiments on three species and surveyed a diverse selection of vascular plants for conduit deformation in leaves.Conduit deformation in minor veins occurred before embolism during slow dehydration. When leaves were exposed to transient increases in transpiration, conduit deformation was accompanied by large water potential differences from leaf to stem and minimal embolism in the upstream xylem. In the three species tested, collapsible vein endings provided clear protection of upstream xylem from embolism during transient increases in transpiration.We found conduit deformation in diverse vascular plants, including 11 eudicots, ginkgo, a cycad, a fern, a bamboo, and a grass species, but not in two bamboo and a palm species, demonstrating that the potential for 'circuit breaker' functionality may be widespread across vascular plants. [ABSTRACT FROM AUTHOR]

This study focuses on the role of the combined gas diffusion layer and membrane on thermal diffusion coefficient and its effects on water transport in polymer electrolyte membrane fuel cell. Thermal diffusion coefficients were reported for water in typical membrane-electrode assemblies. Gas diffusion layers and, in some cases, microporous layers, surrounded the membrane in the center. The sign of the coefficient depended on the materials used. While the Teflon-coated and microporous layer-containing Sigracet 10BC type gas diffusion layer has positive coefficients, the Sigracet type 10BA and 10AA without such microporous layer have negative coefficients. The thermal diffusion coefficient has an activation energy, supporting the idea of water movement by activated jumps. We conclude that hydrophobic layers may significantly improve water and heat transport away from the cathode, and this is why reversible heat transfer should not be neglected in fuel cell studies. [Display omitted] • The thermal diffusion coefficient has a negative sign in hydrophilic and a positive sign in hydrophobic layers. • The thermal diffusion coefficient of a MEA is significantly influenced by the microporous layer. • There is a clear Arrhenius behavior with temperature for the thermal diffusion coefficient of a MEA. • The heat of transfer has a non-negligible effect on the heat flux out of the MEA layers. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) enable extremely fast water transport that make them strong candidates for constructing artificial nanochannels and membranes. However, water transport properties in CNTs with defects along with local charges are rarely studied. In this work, with molecular dynamics simulations, it is found that water transport in CNTs can be greatly modulated by local charges at the CNT middle. The flux modulation factors show an increasing trend with CNT diameters and are slightly influenced by the axial positions of local charges and the CNT lengths. Analysis suggests that water transport is hindered by the confinement-enhanced concentration oscillations and bipolar orientations of water molecules induced by local charges. It is also interesting that the water flux of CNT (6, 6) with high local charges has a reversal behavior due to the overscreening effect. Simultaneously, ions are also impeded due to the water structuring and bipolarizations, which can improve the salt rejection of wide CNTs. In general, introducing local charges on CNT (10, 10) can reject 100% ions while maintaining a high water permeability of ∼90 L/cm2/day/Mpa in the reverse osmosis desalination. This study promotes the understanding of water transport in nanochannels with defects and guides the design of CNTs for high-performance desalination membranes. Graphical abstract showing the RO desalination through CNTs by engineering local charges at the middle (top panel), and the modulation of water transport by adjusting the local charges as well as the comparison of the desalination performance between CNT membranes in this work and the reported novel RO membranes in the literatures (bottom panel). [Display omitted] • Significant modulation of water transport in CNTs by local charges at the middle. • Charge-induced and confinement-enhanced water oscillations and bipolar orientations. • Improved desalination performance for wide CNTs with local charges. • 100% salt rejection and ∼90 L/cm2/day/Mpa water permeability for CNT (10, 10). [ABSTRACT FROM AUTHOR]

In this study, we measured translational water diffusion selectively along symplast pathway through plasmodesmata in maize roots, and the effective plasmodesmata permeability coefficient (P) was determined using a nuclear magnetic resonance (NMR) spin echo method. Measuring of water transport selectively along the plant root plasmodesmata was achieved with paramagnetic complexes (PCs) of high relaxation efficiency. PCs penetrate into the intercellular space of root tissue, but not into cells, and accelerate the magnetic relaxation processes of intercellular water, thereby excluding the contribution of intercellular water to the registered NMR diffusion echo attenuation. In result, NMR control of translational diffusion can be applied to the signal of the water moving along the symplast pathway through plasmodesmata, where the PCs do not penetrate. Diethylenetriaminepentaacetic acid (GdDTPA), Mn2+-trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (MnDCTA), and GdCl 3 were used as PCs. An increase in the PCs concentration led to a side effect in the form of a varying decrease in diffusive water transport in the roots. The P was determined by extrapolating the concentration dependence to zero concentration of PCs. Among the PCs studied, MnDCTA had the least side effects on the water transport when the concentration dependence was linear. When MnDCTA was used, the P accounted for 30–35% of the total cell water permeability (by transmembrane and symplast pathways). The rate of water flow along the plasmodesmata in the approximation of the piston mode of flow along the linear cell chain was estimated to range from 4.5 × 10−7 to 8.8 × 10−7 m/s. • Water transport along plant root plasmodesmata by NMR and paramagnetics was studied. • Paramagnetic complexes can reduce cell-to-cell water transport in plant roots. • The rate of water flow through plasmodesmata was calculated. [ABSTRACT FROM AUTHOR]

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Purpose. The work aims to build a profile of the competitive strategy of inland water transport of Ukraine and its economic justification. Methodology. The theoretical and methodological basis of the study was the fundamental scientific principles of general economic theory and transport economics, works by domestic and foreign scientists in the field of competitive strategies, economic justification of competitive strategy profiles, and sustainable economic development. We used methods such as “SNW”, “SPACE”, and “ADL” to solve the tasks of our research. The information base of the study consists of: collected, processed, and summarized primary materials of economic research, official statistics, monographs, and scientific and analytical articles of domestic and foreign authors. Findings. The work determines the economic essence of the competitive strategy profile. The profile of the Ukrainian inland water transport competitive strategy was constructed. The profile by the method of “SNW” was analyzed and economically justified by the “SPACE” and “ADL” methods. In the context of European integration, a system of strategic recommendations for the Ukrainian inland water transport competitive strategy formation was proposed. Originality. In this work, the methodological approach to building a profile of competitive strategy of inland water transport of Ukraine was further developed, which, in contrast to existing methods, includes critical elements of competitive potential, such as natural resource, production, labor, institutional, innovation and investment ones. This allows a comprehensive assessment of the results of economic threats and dangers in its use. The proposed system of recommendations for forming a competitive strategy, which will allow positioning Ukraine’s inland water transport in the European market of transport services in terms of European integration. Practical value. The presented results of the study can be used to improve the management system of Ukrainian inland waterway transport, in particular, in the part of selecting the most appropriate models of financing costs for the implementation of competitive strategies of water transport in Ukraine in the conditions of structural changes in the macro-environment in the context of overcoming the consequences of military aggression in the period of post-war recovery of Ukraine. [ABSTRACT FROM AUTHOR]

Water management in fuel cells is important for avoiding the phenomenon of flooding or dehydration in the stack and for maintaining good fuel cell performance and durability. This study focuses on the evaluation of the dynamic performance and behaviour (purge cycle) of the commercial Polymer Electrolyte Membrane (PEM) fuel cell stack towards water transport (water balance) at different operating conditions. The stack was operated at different current loads (0–10 A) and operating temperature (ambient to 50 °C). The results indicated that the measured water accumulation in the stack increased with the increase in current load. The optimal current load was 4 A, with calculated efficiency of 62.8%. The optimal operating temperature was 40 °C, resulting in calculated efficiency of 52.3%. At higher temperature, the fuel cell performance decreased, and the measured water balance was not properly distributed, which could be due to the dehydration and low conductivity of the electrolyte membrane. It can be concluded that the behaviour and performance of the stack, as well as the water balance in the stack, were influenced by the operating conditions. Moreover, this study improves the understanding of fuel cell performance and behaviour based on evaluation of the water balance. [ABSTRACT FROM AUTHOR]

Atomically thin nanoporous 2D membranes, featuring unique sieving characteristics for molecules and ions, have significant potential for seawater desalination. However, they face a common trade-off between permeability and selectivity. Here, we report an ultrathin stacked nanoporous graphene membrane (SNGM) created by layering atomically thin graphene nanomesh. This design achieves highly efficient and selective sieving of water molecules and ions. The SNGMs showcase in-plane nanopores for optimal size-exclusive water input and output, and interlayer 2D nanochannels between adjacent graphene nanomesh membranes for rapid water transport and precise ion/molecular sieving. The resulting SNGMs effectively address the trade-off between water permeability and ion selectivity in conventional desalination membranes, delivering a water permeability of ∼ 1-2 orders of magnitude higher than that of commercial membranes, while maintaining a comparable ion rejection ratio (>95% for NaCl). This advance marks a significant leap forward in adopting 2D nanoporous membranes for desalination technology., Competing Interests: None declared., (© The Author(s) 2025. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Two-dimensional covalent organic frameworks (2D COFs), a family of crystalline materials with abundant porous structures offering nanochannels for molecular transport, have enormous potential in the applications of separation, energy storage, and catalysis. However, 2D COFs remain limited by relatively large pore sizes (>1 nm) and weak interlayer interactions between 2D nanosheets, making it difficult to achieve efficient membranes to meet the selective sieving requirements for water molecules (0.3 nm) and hydrated salt ions (>0.7 nm). Here, we report a high-performance 2D COF membrane with narrowed channels (0.7 × 0.4 nm 2 ) and excellent mechanical performance constructed by the staggered stacking of cationic and anionic 2D COF nanosheets for selectively sieving of water molecules and hydrated salt ions. The mechanical performance has been improved by two times than that of single-phase 2D COF membranes due to the enhanced interlayer interactions between nanosheets. The stacked 2D COF membranes exhibit significantly improved monovalent salt ions rejection ratio (up to 77.9%) compared with single-phase COF membranes (∼49.2%), while maintaining comparable water permeability. The design of stacked 2D COF membranes provides a potential strategy for constructing high-performance nanoporous membranes to achieve precise molecular and ionic sieving.

Abstract This study established a systematic simulation framework to predict the anti-icing longevity of a thin overlay of asphalt pavement with salt-storage additive (APSSA). The water and chloride transport in the overlay when subjected to varying precipitation, temperature, thermal cracking, and fatigue cracking over time were modeled using a Finite Element Method based software. The simulation included two parts: water transport followed by chloride transport. Water transport that obeys the law of conservation of mass was modeled using the phase transport in porous media (phtr) interface of COMSOL, while chloride transport based on Fick’s second law was modeled with the transport of diluted species (tds) interface. The simulation results show that the anti-icing function of a 16-mm thick overlay was fully effective in 2 years and 5 years for the minimum pavement temperature above -3.4 °C and -2.4 °C, respectively. These two pavement temperatures are equivalent to 97.4-percentile and 96.3-percentile of historical hourly pavement temperature near Pullman, Washington. Graphical abstract

The spontaneous wetting and drying of flat porous samples of linen, cotton and synthetic textiles were studied using dynamic neutron radiography (DNR). The progress of the wetting process of the media was delineated from the obtained neutron dynamical radiography images. The results of the investigation reveal a non-classical behaviour of kinetics of wicking of these materials. The character of the wetting kinetics is discussed in terms of the fractal character of the tortuosity of fabric capillaries.

Using phase-contracted synchrotron X-ray tomography, this study investigates the water distribution within the microporous layer (MPL) of polymer electrolyte membrane fuel cells (PEMFCs). Synchrotron X-ray tomography used to analyze the water distribution in the whole gas diffusion medium (GDM), which comprises the microporous layer (MPL) and the gas diffusion layer (GDL). The MPL has already been identified. In the future, the development of GDMs could be employed to enhance the performance and operating conditions of PEMFCs.

Estuarine projects can quickly change the estuarine topography and influence the hydrodynamics and saltwater intrusion. The Changjiang Estuary is a multiple-bifurcation megaestuary, and the outstanding feature of the saltwater intrusion is the saltwater spillover from the North Branch (NB) into the South Branch (SB). In this study, the improved ECOM-si model was adopted to numerically experiment with the impact of the sluices that are planned for construction in the upper, middle, and lower reaches of the NB on the saltwater intrusion and freshwater resources. The simulation results show that, on the one hand, sluice construction can eliminate the saltwater spillover from the NB into the SB; on the other hand, sluice construction makes water enter the NB from the SB, and the runoff discharging into the sea in the SB decreases. The water intake time of the Qingcaosha Reservoir (QCSR) increases by 3.2 days for sluice construction in the upper reaches of the NB and decreases by 0.97 and 0.94 days for sluice construction in the middle and lower reaches of the NB, respectively. Considering the impact of sluice construction in the NB on the saltwater intrusion and freshwater resources, the construction of sluices in the upper reaches of the NB is recommended.

The Carbon Intensity Index (CII) exerts a substantial impact on the operations and valuation of international shipping vessels. Accurately predicting the CII of ships could help ship operators dynamically evaluate the possible CII grate of a ship at the end of the year and choose appropriate methods to improve its CII grade to meet the IMO requirement with minimum cost. This study developed and compared five CII predicting models with multiple data sources. It integrates diverse data sources, including Automatic Identification System (AIS) data, sensor data, meteorological data, and sea state data from 2022, and extracts 21 relevant features for the vessel CII prediction. Five machine learning methods, including Artificial Neural Network (ANN), Support Vector Regression (SVR), Least Absolute Shrinkage and Selection Operator (LASSO), Extreme Gradient Boosting (XGBoost), and Random Forest (RF), are employed to construct the CII prediction model, which is then applied to a 2400 TEU container ship. Features such as the mean period of total swell, mean period of wind waves, and seawater temperature were considered for inclusion as inputs in the model. The results reveal significant correlations between cumulative carbon emissions intensity and features like cumulative distance, seawater temperature, wave period, and swell period. Among these, the strongest correlations are observed with cumulative distance and seawater temperature, having correlation coefficients of 0.45 and 0.34, respectively. Notably, the ANN model demonstrates the highest accuracy in CII prediction, with an average absolute error of 0.0336, whereas the LASSO model exhibits the highest error of 0.2817. Similarly, the ANN model provides more accurate annual CII ratings for the vessel. Consequently, the ANN model proves to be the most suitable choice for cumulative CII prediction.

With the rapid development of nanofluidics, more and more unexpected behaviors and bizarre properties have been discovered, which brings more possibility to solve the water and energy problem. Carbon nanotubes (CNTs) with nanoscale diameter and ultrasmooth hydrophobic surface provide strong confinement and unusual water‐carbon couple which lead to many exotic properties, such as flow enhancement, strong ion exclusion, ultrafast proton transport and phase transition. This article reviews the recent progresses of CNT‐based nanofluidic devices in fabrication, property, and applications. Moreover, challenges and opportunities of the CNT‐based nanofluidic devices are discussed. [ABSTRACT FROM AUTHOR]

Phase H (MgSiO4H2), one of the lower mantle's dense hydrous magnesium silicates (DHMSs), may form and exist in cold slabs and is crucial in carrying water into the deep mantle. Its sound velocities and density are crucial for inferring the mid‐mantle water cycling via seismic approaches. Here we obtain the elastic and thermodynamic properties of phase H under lower‐mantle conditions using first‐principles calculations and discuss the effect of the Mg‐Si disorder on elasticity. The density of phase H is ∼15% and ∼6% lower than that of bridgmanite and periclase, respectively. The dehydration reaction from phase H to bridgmanite, which may occur at the depth of ∼1,300–1,700 km in cold slabs, will cause an increase of 1.0%, 2.7%, and 15% at 1,500 km on VP, VS, and density, respectively. The dehydration of phase H in subduction zones could produce a seismic VS impedance contrast of ∼17% in the mid‐mantle, which can provide an explanation for some seismic discontinuities detected by previous studies. Meanwhile, phase H has remarkable anisotropies and this may help explain the observed seismic anisotropy within subduction zones. Collectively, our results suggest that some seismic observations in mid‐mantle slabs may be related to the presence of phase H formed via the deep water cycle, further constraining the potential water content in local regions of the subducted slabs. Plain Language Summary: The deep water cycle (DWC) strongly influences the evolution of the planet. But whether hydrous minerals could be carried into the lower mantle or not, which fundamentally impacts our understanding of the DWC, remains controversial. Dense hydrous magnesium silicates (DHMSs), which have been widely conducted by theoretical and experimental investigations in recent years, are considered to be the major carriers for transporting water to the deep mantle in a cold slab. However, the elastic data of phase H, the deepest DHMSs, are not available under the mantle temperatures and pressures. Here we conducted first‐principles calculations to investigate the thermodynamic properties and elastic properties of phase H under the lower mantle conditions. We find that the dehydration of phase H into bridgmanite, which may occur at the depth of ∼1,300–1,700 km in a cold slab, will produce a seismic VS impedance contrast of ∼17%. Thus, the dehydration of the moderate amount of phase H at these depths could generate the seismic discontinuities detected in some subduction zones. Our results provide evidence of water transport in the mid‐mantle. Key Points: We calculate thermodynamic and elastic properties of phase H at mid‐mantle conditions using first‐principles calculationsDehydration of phase H causes significant density jump and moderate VS jump and provides an explanation for mid‐mantle discontinuitiesSome cold slabs may enrich water in the mid‐mantle by the dehydration of phase H [ABSTRACT FROM AUTHOR]

The shape of a nanochannel significantly affects mass transport. This study provides a new nanochannel model made from a concentric-twin tube (CTT), which can be made by inserting a carbon nanotube (CNT) into another identical CNT. The stable configuration of such a CTT has three subchannels containing different cross-sectional shapes. Molecular dynamic approach is applied to evaluate the transport performances of the confined water in the CTT. Molecular dynamics simulations indicate that the CTT made from (17,17) CNTs is the thinnest nanochannel for water transport. The three subchannels of a CTT have different linear speeds of water and different volume flow rates depending on the CTT's cross-sectional shapes. Based on these characteristics, a fluid nanodevice requiring special transform performances, e.g., sieving the molecules with different sizes in a solution, can be designed from the new nanochannels. [ABSTRACT FROM AUTHOR]

Trees develop wood grain more or less parallel to the tree axis as they grow laterally. However, many tree species also develop interlocked grain that is expressed as a change in the wood grain orientation, periodically switching between left- and right-handed spirals over the years. Wood grain information is critical to determining the wood quality and is an important record of cellular events in a cambium. This study examined the wood grain of axial xylem cells in the semi-ring porous hardwood Cinnamomum camphora by first visualizing the three-dimensional structure using a conventional X-ray computed tomography instrument producing tomography images. We propose the use of particle image velocimetry (PIV) and the two-dimensional fast Fourier transform (2D-FFT) to analyze computed tomography images in obtaining grain angle (δ) information from the vessel deviation. We found undulation on the radial variation of the grain angle (δ) that indicates periodical changes in the wood grain orientation as left- and right-handed spirals ranging from − 25° to 16° and − 22° to 18° using the 2D-FFT and PIV, respectively. Furthermore, despite the major orientation of vessels inclining in the tangential direction, the PIV result revealed a minor deviation with vessels inclining in various orientations along the tree radius. [ABSTRACT FROM AUTHOR]

The Mediterranean-Black Sea system consists of two semi-enclosed basins connected by the Turkish Straits. In turn, the Mediterranean Sea is connected to the Atlantic Ocean through the narrow Strait of Gibraltar. The hydrological cycle of the system is driven by fresh water exchanges between the atmosphere, continents and oceans, and by salty water mass exchange among the ocean basins. Monitoring such water fluxes, especially its time evolution, is essential to understand the water cycle in the region, which is very sensitive to global climate changes and influences the variability of the Atlantic Meridional Overturning Circulation (AMOC), which in turn affects the global climate. In this study, we have estimated the hydrological cycle of the Mediterranean-Black Sea system from the time-variable gravity observations performed by the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On satellites, and precipitation and evaporation from ERA5 atmospheric reanalysis data for the period 2002–2020. In the Black Sea, rivers introduce an average water volume of 391 ± 12 km3/year, one third of which escape through the atmosphere and two thirds go to the Mediterranean Sea. In the latter, 1787 ± 23 km3/year are lost via net evaporation. The rivers runoff (502 ± 27 km3/year), and the inflow of Atlantic waters (1020 ± 56 km3/year; 0.0323 ± 0.0018 Sv), finally restore the Mediterranean water budget. The balance is not reached instantaneously, and this delay introduces a seasonal variability in all the fluxes. In particular, the net water flux from the Atlantic Ocean increases up to 2660 ± 111 km3/year in August/September, and reverses to − 407 ± 140 km3/year in April/May. On top of the climatology, the mean annual Atlantic water flux varies significantly between 706 and 1262 km3/year. [ABSTRACT FROM AUTHOR]

Dangerous goods (DGs) not declared for transport as required by the regulations can give rise to risks, as they can endanger public safety or the environment. This study explains the risks posed by undeclared shipments by providing information about the most common undeclared DGs aboard aircraft and maritime ships, legal frameworks regulating the proper transportation of DGs, and key mechanisms for preventing the occurrence of undeclared DG shipments. This paper identifies the responsibilities of each stakeholder involved in the process of DG transportation. The main objective of this paper is to reveal human errors and dishonest techniques within the supply chain when DGs are transported by air and sea. [ABSTRACT FROM AUTHOR]

In the present work, the effects on water transport due to the orientation of the layer in the multilayered porous graphene and the different patterns formed when the layer is oriented to some degrees are studied for both circular and non-circular pore configurations. Interestingly, the five-layered graphene membrane with a layer separation of 3.5 Å used in this study shows that the water transport through multilayered porous graphene can be augmented by introducing an angle to certain layers of the multilayered membrane system. [ABSTRACT FROM AUTHOR]

A 3D compressed gas diffusion layer (GDL) microstructure is developed based on the finite volume method (FVM) and used to evaluate water transport behavior. The compressed GDL microstructure and two-phase flow VOF model are developed and validated on the OpenFOAM CFD platform. The models are compared to experimental data, with good agreement. Consequently, the reconstructed GDL microstructures are subjected to compressive stresses. The water uptake behavior in the compressed samples with different (CR) compression ratios (10% CR, 20% CR, and 40% CR) is compared to that in an uncompressed GDL microstructure. Also, the effects of GDL wettability, water pressure, and non-uniform fiber diameter arrangement in GDLs are investigated. In GDL microstructures, two-phase interaction is influenced by the GDL contact angle, compression ratio, water inlet pressure and capillary pressure. It is found that excessive compression on GDLs constricts the pores, thereby restricting access of water through the pores. As such, 10% CR was found to be the safe limit with just 8% saturation drop. On the other hand, altering the fiber structural arrangement through unequal-sized fiber diameter had very little impact on water saturation in the through-plane direction of both the uncompressed and compressed GDL microstructures. As such, the excessive introduction of the unequal-sized fibers may not be the right choice, especially under compressive forces. Thus care must be taken in the treatment of GDL carbon papers and clamping force during assembly since these significantly influences water patterns in them. [ABSTRACT FROM AUTHOR]

Wetting and wicking are among the essential behaviors of fabric. Woven fabric is interwoven by the warp and weft yarn, and it can be considered as a yarn network. To clarify the wicking phenomenon of woven fabric and simulate its water transport, the wicking behaviors in the vertical and horizontal directions of six yarn samples were examined. The moisture movement of these interlacing silk yarns was clarified. The wicking behaviors of the silk yarn were found to increase at the first initial stage, and decrease with time until the yarn is saturated. The wicking length of the vertical direction revealed that the fiber and void areas in the silk yarn have an essential effect on water transport. Further, the wicking relationship between single and interlaced yarns was also discussed. The good relationship between the wicking length of single and interlaced yarns shows the possibility of predicting the wicking ability of the textile through the initial wicking ability of the single yarn in the future. [ABSTRACT FROM AUTHOR]

The goal of this study was to investigate the functional implications of sex and species differences in the pattern of transporters along nephrons in the rat and mouse kidney, as reported by Veiras et al. (J Am Soc Nephrol 28: 3504–3517, 2017). To do so, we developed the first sex-specific computational models of epithelial water and solute transport along the nephrons from male and female mouse kidneys, and conducted simulations along with our published rat models. These models account for the sex differences in the abundance of apical and basolateral transporters, glomerular filtration rate, and tubular dimensions. Model simulations predict that 73% and 57% of filtered Na+ is reabsorbed by the proximal tubules of male and female rat kidneys, respectively. Due to their smaller transport area and lower NHE3 activity, the proximal tubules in the mouse kidney reabsorb a significantly smaller fraction of the filtered Na+, at 53% in male and only 34% in female. The lower proximal fractional Na+ reabsorption in female kidneys of both rat and mouse is due primarily to their smaller transport area, lower Na+/H+ exchanger activity, and lower claudin-2 abundance, culminating in significantly larger fractional delivery of water and Na+ to the downstream nephron segments in female kidneys. Conversely, the female distal nephron exhibits a higher abundance of key Na+ transporters, including Na+-Cl− cotransporters in both species, epithelial Na+ channels for the female rat, and Na+-K+-Cl−cotransporters for the female mouse. The higher abundance of transporters accounts for the enhanced water and Na+ transport along the female rat and mouse distal nephrons, relative to the respective male, resulting in similar urine excretion between the sexes. Model simulations indicate that the sex and species differences in renal transporter patterns may partially explain the experimental observation that, in response to a saline load, the diuretic and natriuretic responses were more rapid in female rats than males, but no significant sex difference was found in mice. These computational models can serve as a valuable tool for analyzing findings from experimental studies conducted in rats and mice, especially those involving genetic modifications. [ABSTRACT FROM AUTHOR]

Summary: Fine‐scale topographic–edaphic gradients are common in tropical forests and drive species spatial turnover and marked changes in forest structure and function. We evaluate how hydraulic traits of tropical tree species relate to vertical and horizontal spatial niche specialization along such a gradient.Along a topographic–edaphic gradient with uniform climate in Borneo, we measured six key hydraulic traits in 156 individuals of differing heights in 13 species of Dipterocarpaceae. We investigated how hydraulic traits relate to habitat, tree height and their interaction on this gradient.Embolism resistance increased in trees on sandy soils but did not vary with tree height. By contrast, water transport capacity increased on sandier soils and with increasing tree height. Habitat and height only interact for hydraulic efficiency, with slope for height changing from positive to negative from the clay‐rich to the sandier soil. Habitat type influenced trait–trait relationships for all traits except wood density.Our data reveal that variation in the hydraulic traits of dipterocarps is driven by a combination of topographic–edaphic conditions, tree height and taxonomic identity. Our work indicates that hydraulic traits play a significant role in shaping forest structure across topographic–edaphic and vertical gradients and may contribute to niche specialization among dipterocarp species. [ABSTRACT FROM AUTHOR]

In order to study the influence of the geometric structure of the perforated plate in plant xylem ducts on water transmission, the models of different types of perforated plates were established, combined with Bernoulli equation, and the method of computational fluid dynamics was used for the ducts with different geometric structures of perforated plates. The internal flow field was numerically simulated. The relationship between the pressure drop at both ends of the catheter, the hydraulic conductivity and the equivalent length of the perforated plate, and the perforation type, equivalent area ratio, number of holes, inclination angle and the inner diameter of the perforated plate were analyzed. The results showed that, for a specific perforated plate model, when other parameters were the same, compared with a simple perforation plate, the equivalent length of the gnetum type perforation plate increased by 15. 01%, and the pressure drop at both ends of the catheter increased by 3. 92%. The equivalent length of the reticulate perforation plate increased by 112. 76%, and the pressure drop at both ends of the duct increased by 29. 43%. The equivalent length of the scalariform perforation plate increased by 148. 70%, and the pressure drop at both ends of the duct increased by 38. 81%. The equivalent length of the ephedroid perforation plate increased by 205. 70%, and the pressure drop at both ends of the catheter increased by 53. 68%. For these 5 types of perforated plates, larger equivalent area ratio, more holes, smaller angle of inclination and larger pipe diameter meant that the pipe ends had greater pressure drop and perforated plates had a larger equivalent length. When the number of holes in the perforated plate was constant and other parameters were the same, the hydraulic conductivity of the duct was proportional to the inner diameter of the duct. The hydraulic conductivity of the duct where the perforated plate was located obeys the following order (from big to the small): non-perforated plate, simple perforated plate, gnetum type perforated plate, reticulate perforated plate, scalariform perforated plate, ephedroid perforated plate. The research results provided a theoretical basis for in-depth study of plant xylem water transport characteristics. [ABSTRACT FROM AUTHOR]

The confined water flow through forsterite nanoslits is vital to the security of CO2 geological sequestration in deep saline aquifers. Molecular dynamics simulations for confined water in the forsterite nanoslits are performed in this work. We investigate the effects of nanoslit height, hydraulic pressure drop, temperature and hydrostatic pressure on the water flow characteristics. Firstly, equilibrium molecular dynamics simulations are conducted to select a minimum nanoslit height for the subsequent non-equilibrium molecular dynamics (NEMD) simulations, to weaken the ultra-dominant nano-confinement effect on water flow. NEMD simulations reveal that the velocity profiles transfer from parabolic to plug-like shape with the increase in hydraulic pressure drop. The distance-dependent shear viscosity is determined by analyzing velocity profiles. The results indicate that the confined water gradually deviates from the Newtonian to non-Newtonian fluid, resulting from the more condensed water molecule layers introduced by the large hydraulic pressure drop. Additionally, we demonstrate that the water flow is enhanced with the temperature increasing. The enhancement in water flow is attributed to the shear viscosity reduction, resulting from the looser hydrogen-bonding network. Comparatively, the impact of variations in the hydrostatic pressure on the velocity profiles and shear viscosity is insignificant. This work provides atomistic insights into the non-Newtonian transport behaviour of high velocity water flow under nano-confinement or extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Main conclusion: In Dracaena draco trunks, the primary and secondary xylem conduits co-function. Both are resistant to embolism; however, secondary conduits are mainly involved in mechanical support. Monocotyledonous dragon trees (Dracaena spp., Asparagaceae) possess in their trunks both primary and secondary xylem elements, organized into vascular bundles, that for dozens of years co-function and enable the plant to transport water efficiently as well as provide mechanical support. Here, based on the modified Hagen-Poiseuille’s formula, we examined the functional anatomical xylem traits of the trunk in two young D. draco individuals to compare their function in both primary and secondary growth. We provided analyses of the: (i) conduits surface sculpture and their cell walls thickness, (ii) conduit diameter and frequency, (iii) hydraulically weighted diameter, (iv) theoretical hydraulic conductivity, (v) area-weighted mean conduit diameter, as well as (vi) vulnerability index. The conduits in primary growth, located in the central part of the trunk, were loosely arranged, had thinner cell walls, larger mean hydraulically weighted diameter, and significantly larger value of the theoretical hydraulic conductivity than conduits in secondary growth, which form a rigid cylinder near the trunk surface. Based on the vulnerability index, both primary and secondary conduits are resistant to embolism. Taking into account the distribution within a trunk, the secondary growth conduits seems to be mainly involved in mechanical support as they are twisted, form structures similar to sailing ropes and have thick cell walls, and a peripheral localization. D. draco has been adapted to an environment with water deficit by distinctive, spatial separation of the xylem elements fulfilling supportive and conductive functions. [ABSTRACT FROM AUTHOR]

The purpose of this study was mathematical model development for assessing the cost of losses from risks in the maritime transportation of goods that are dynamic in nature, and developing a methodical approach to the dynamic costs assessment for each of the risks separately and integral costs for all risks and ensuring the fulfillment of the requirement to anticipate the insurance cost changes over the rate of change of the transportation integral risk (or its stage). The risks factor analysis in water transport, their classification and determination of the type and nature of their impact on sea transportation of goods were carried out. The groups of risk factors that lead to emergency situations for water transport in Ukraine were studied by comparing the data of 2019 and 2021 and determining their share in the total number of accidents before the start of the active phase of hostilities in Ukraine; the rates of their change were analyzed. This made it possible to develop a systematic assessment algorithm for the dependence of the expected and actual value of losses on risks and to create a mathematical approach to risks forecasting as a factor influencing the cost of expenses. As a result of the study, a methodical approach to forecasting the cost of losses from risks was formed for each of their types. However, the main attention was paid to the identification and assessment of dynamic risks, the impact of which has an absorbing nature relative to all others in their totality. Such risks in the waters of the Black and Azov seas today mainly include risks associated with the conduct of military operations, including such operations that go against international legal norms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three-dimensional carbon-silicon composites (3D-CS) is prepared from coal gasification slag. • 3D-CS exhibits the exceptional photothermal conversion and water transport properties. • 3D-CS facilitates the transformation of liquid water into vapor at the solid–liquid interface. • 3D-CS is a low-cost and high-efficiency materials for solar-driven interfacial evaporation. Coal gasification slag (CGS) is a solid waste produced during the coal gasification process, posing an urgent challenge in the modern coal chemical industry. This study presents a method for producing three-dimensional carbon-silicon composite materials (3D-CS) from CGS to facilitate solar-driven interfacial evaporation, leveraging the photothermal conversion capabilities of carbonaceous components and the high reactivity of inorganic components in CGS. The research focuses on the preparation process of 3D-CS from CGS, analyzing its photothermal conversion and water transport properties, as well as its performance in solar-driven interfacial evaporation. The results reveal that 3D-CS prepared from CGS exhibits outstanding photothermal conversion efficiency, achieving a light absorption capacity of 92.5 % in the full solar spectrum; and the surface temperature of 3D-CS can rapidly increase from 27.2 °C to 39.3 °C within 10 s under one sun. The hierarchical pore structure of 3D-CS formed by the loose, porous silicon aggregates and irregular, hole-shaped carbonaceous components, facilitating to its water transport capabilities. Notably, when the silicon concentration is 40 g/L, the carbon content is 10 %, and the aging time is 2 days, the evaporation rate of 3D-CS can reach 1.73 kg·m−2·h−1 (evaporation efficiency of 86.21 %) under one sun; and the evaporation rate can still be maintained above 1.65 kg·m−2·h−1 after 30 cycles. CGS-based 3D-CS with the exceptional photothermal conversion and water transport properties demonstrate remarkable performance in solar-driven interfacial evaporation. This approach not only addresses environmental concerns associated with CGS, but also produces low-cost and high-efficiency materials for solar-driven interfacial evaporation, offering potential for the resource recycling of industrial solid waste. [ABSTRACT FROM AUTHOR]

Despite extensive research on farmers' constraints and decisions, technology developers, policymakers and development organizations still encounter difficulties in relating policies to farmers' strategies. Often, the concept of ‘smallholders' is applied as explaining and predicting farmers' decisions—suggesting that specific strategies of farmers can be meaningfully related to their farm size. Our study into farmers' decision-making concerning water transport technologies in Malawi suggests that this way of grouping farmers in policy and development programs does not match actual decision strategies. Using Q-methodology (Q) as a method allowed us to find decision-making patterns without predefining variables that would influence decision-making. We found that farmers within a predefined smallholder group did not decide in the same ways. Furthermore, our results show that decision-making has a clear gender dimension. We argue that Q is able to capture the nuances of farmers' decision-making processes. As such, the methodology potentially provides a useful feed for policy and technology development.

The goal of this study was to investigate the functional implications of sex and species differences in the pattern of transporters along nephrons in the rat and mouse kidney, as reported by Veiras et al. (J Am Soc Nephrol 28: 3504–3517, 2017). To do so, we developed the first sex-specific computational models of epithelial water and solute transport along the nephrons from male and female mouse kidneys, and conducted simulations along with our published rat models. These models account for the sex differences in the abundance of apical and basolateral transporters, glomerular filtration rate, and tubular dimensions. Model simulations predict that 73% and 57% of filtered Na+ is reabsorbed by the proximal tubules of male and female rat kidneys, respectively. Due to their smaller transport area and lower NHE3 activity, the proximal tubules in the mouse kidney reabsorb a significantly smaller fraction of the filtered Na+, at 53% in male and only 34% in female. The lower proximal fractional Na+ reabsorption in female kidneys of both rat and mouse is due primarily to their smaller transport area, lower Na+/H+ exchanger activity, and lower claudin-2 abundance, culminating in significantly larger fractional delivery of water and Na+ to the downstream nephron segments in female kidneys. Conversely, the female distal nephron exhibits a higher abundance of key Na+ transporters, including Na+-Cl− cotransporters in both species, epithelial Na+ channels for the female rat, and Na+-K+-Cl−cotransporters for the female mouse. The higher abundance of transporters accounts for the enhanced water and Na+ transport along the female rat and mouse distal nephrons, relative to the respective male, resulting in similar urine excretion between the sexes. Model simulations indicate that the sex and species differences in renal transporter patterns may partially explain the experimental observation that, in response to a saline load, the diuretic and natriuretic responses were more rapid in female rats than males, but no significant sex difference was found in mice. These computational models can serve as a valuable tool for analyzing findings from experimental studies conducted in rats and mice, especially those involving genetic modifications.

[Display omitted] • An efficient water transport system inspired by plant roots in the whole-root MPL. • Separated gas transfer channels and water transport pathways. • Lowered water breakthrough pressure from 20.7 kPa to 7.5 kPa. • A high peak power density up to 1.84 W cm−2 in a hydrogen/air fuel cell. • Roll-to-roll production to match the most commercial fuel cell stacks. Elevating power density is eagerly desired to improve specific power and reduce costs for fuel cells. Unfortunately, the high water breakthrough pressure and shared water/gas transport pathways of the microporous layer (MPL) astrict the electrode from ultimate power density. Herein, inspired by plant roots, we engineered a highly efficient biomimetic water transport system with lateral root-like water collectors and axial root-like water transport channels. Not only the breakthrough pressure is greatly reduced from 20.7 kPa to 7.5 kPa, but also the gas transfer channels (hydrophobic pores) and water transport pathways are separated in whole-root MPL. Consequently, the peak power density is substantially elevated to 1.84 W cm−2 (1.86 times of conventional MPL). Moreover, the electrode flooding is significantly mitigated, and the frequency reduces from 2.6 to 0.4 times per hour. The whole-root MPL can be massively produced and has substantial potential in promoting power density for forthcoming fuel cells. [ABSTRACT FROM AUTHOR]

Ion transport peptide (ITP) and ITP-like (ITPLs) are pleiotropic bioactive peptides in insects. Although the contribution of these peptides to ecdysis has been studied, the precise regulatory mechanisms remain poorly understood. Here, we characterized the functions of itp and itpl variants in the two-spotted cricket, Gryllus bimaculatus. Reverse transcription-quantitative PCR and whole-mount in situ hybridization revealed that itp was expressed in the brain and terminal abdominal ganglion, whereas itpl variants were expressed in all ganglia of the central nervous system. Simultaneous knockdown of itp and itpls disrupted ecdysis behavior and water transport from the gut into the hemolymph during molting. Nevertheless, knockdown of itpls without influencing itp expression did not significantly affect ecdysis behavior but caused a reduction in hemolymph mass. Although water transport into the hemolymph is considered necessary for the swelling required to split the old cuticle layers during molting, a rescue experiment by injection of water or cricket Ringer's solution into the hemolymph of knockdown crickets did not recover the normal phenotype. Therefore, we propose that ITP/ITPL control ecdysis behavior probably not by regulating water transport from the gut into the hemolymph in crickets. [Display omitted] • cDNAs encoding itp and itpls in Gryllus bimaculatus were identified and characterized. • Shedding of the old cuticle during molting was promoted by itp/itpls signaling. • Transient transport of water from the gut to the hemolymph occurred during molting to facilitate shedding in crickets. • Water transport from the gut to the hemolymph during molting was induced by itp/itpls signaling. [ABSTRACT FROM AUTHOR]

• A method based on X-ray radiography was proposed here to map out the 2D distribution of internal moisture content changes throughout the wetting and drying process. • This method realizes the calibration of water content without using developer, and demonstrates a significant tolerance for variations in w/cm ratio, cement type and samples sizes. • A monochromatic index was introduced to determine the XR syetem paramter. • Experimental results that high-quality imaging can be sustained, and beam hardening effect can be mitigated when employing a high tube voltage of 150 kV. • When compared to the gravimetric method, the relative error of quantitative water content obtained from this method was not more than 5.76 %. The infiltration of water is a crucial factor in the degradation of the durability of concrete structures. It is important to conduct wetting and drying experiments to validate the water transport performance of construction materials during their service life, with precise measurement of both the process and the outcomes being essential. This study proposes a 2D quantitative detection method based on X-ray Radiography to determine the distribution of moisture content. This technique enhances conventional X-ray Radiography methods by utilizing a higher tube voltage to mitigate the impact of beam-hardening effects, as explained by the monochromatic index introduced here, and employs a coefficient matrix for correcting field non-uniformity and a spatial positioning algorithm to rectify discrepancies among multiple measurements. This method offers several benefits due to its capacity to provide in-time, accurate, non-contact, and cost-efficient quantitative results without any contrast agent while maintaining appropriate spatial resolution. The feasibility of this method is verified through a wetting and drying experiment taking cement paste material as an example. When compared with the gravimetric method, experimental results show that the relative error of moisture content obtained from this method is less than 5.76 %. [ABSTRACT FROM AUTHOR]