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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.

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]

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]

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]

Aquaporins (AQPs) are small transmembrane tetrameric proteins that facilitate water, solute and gas exchange. Their presence has been extensively reported in the biological membranes of almost all living organisms. Although their discovery is much more recent than ion transport systems, different biophysical approaches have contributed to confirm that permeation through each monomer is consistent with closed and open states, introducing the term gating mechanism into the field. The study of AQPs in their native membrane or overexpressed in heterologous systems have experimentally demonstrated that water membrane permeability can be reversibly modified in response to specific modulators. For some regulation mechanisms, such as pH changes, evidence for gating is also supported by high-resolution structures of the water channel in different configurations as well as molecular dynamics simulation. Both experimental and simulation approaches sustain that the rearrangement of conserved residues contributes to occlude the cavity of the channel restricting water permeation. Interestingly, specific charged and conserved residues are present in the environment of the pore and, thus, the tetrameric structure can be subjected to alter the positions of these charges to sustain gating. Thus, is it possible to explore whether the displacement of these charges (gating current) leads to conformational changes? To our knowledge, this question has not yet been addressed at all. In this review, we intend to analyze the suitability of this proposal for the first time. [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]

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]

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]

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]

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]

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]

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 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]

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]

Water processes secure plant survival and maintain their ecosystem function. Salinity affects water processes, but the mechanisms remain unclear and may depend on the degree of salinity stress. To improve the understanding of the cooperation of plant organs involved in water processes under salinity stress, we determined hydraulic, gas exchange, and physiological and biochemical parameters in Populus euphratica Oliv. under different salinity stresses. The results suggested that P. euphratica enhanced water transport efficiency in a salinity-stress environment, and the strengthening effect of roots in the water transfer process was greater than that of the aboveground parts. P. euphratica also increased water use efficiency and water transport efficiency in mild and moderate salinity stress (less than 200 mmol/L NaCl) but was adversely affected by heavy salinity stress (more than 300 mmol/L NaCl). Furthermore, P. euphratica increased its water storage by regulating antioxidant enzyme scavenging capacity and osmoregulation, which resulted in coordinated greater water utilization and enhanced water transport among plant organs and indicated that the adverse effects on water processes triggered by salinity stress depended on the extent of salt stress. P. euphratica lessened stress-induced damage and maintained plant productivity by coordination and cooperation of water processes under certain levels of salinity. Research on the coordination and cooperation involving water processes in riparian forests in saline areas provides the scientific basis for riparian plant protection and restoration., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Si and Ren.)

Abstract 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.

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.

Forest decline is a significant issue affecting critical ecosystem processes worldwide. Here, we describe mortality in Pinus sylvestris L. monitored trees caused by the inhabitation of pine bark beetles (Tomicus minor Hart.) in symbiosis with ophiostomatoid fungi (Ophiostoma piceae (Munch) H. et P. Sydow) infection in the forest-steppe of central Siberia. Stem sap flow (Q) and stem diameter fluctuations (dRc) were monitored in eight pine trees during seven consecutive growing seasons (2015–2021). In addition, microcore sampling every ten days allowed the determination of stem wood formation in monitored trees in the 2021 growing season. During 2020 and 2021, two cases of Q termination were recorded among the monitored trees, with microcores revealing no cambium formation. Thus, the seasonal Q onset matches the beginning of the beetle dispersal period when they attack and inhabit tree stems. The decline of circumferential stem size began 10–12 days after Q onset, during the massive inhabitation of beetles into the stems. The disturbance of Q in trees occurred in 21–23 days, and total cessation of Q was observed 23–26 days after the Q onset at the beetle’s egg development phase. The timing of dRc disturbance and Q cessation observed directly coincides with the beetle life cycle. Thus, the phenology of pine trees and T. minor beetles is driven by seasonal weather conditions, particularly the cumulative air temperature (>0 °C).

A new enhanced drainage parallel (EDP) flow field was designed that not only enhances under-rib convection but also enables a more uniform distribution of hydrogen and oxygen. Through the optimization of the model, we established the influence of the flow field size, relative humidity, and stoichiometric ratio on cell performance. When the rib width is reduced, the maximum power density is improved. Compared with the parallel flow field and serpentine flow field, the maximum power density of the EDP flow field was increased by 69.4% and 7.9%, respectively. Under optimal conditions, the net power of the EDP flow field can reach 0.56 W/cm2. In the single-cell test, the maximum power density of the EDP flow field can reach 1.19 W/cm2. This implies that the EDP flow field has potential application of proton exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]

High toxicity of water resources by heavy metal ions is common and membrane filtration is one the solutions to this problem. Titanate nanotubes (TNT) are generally used due to their unique characteristics such as meso-porous structure, and high specific surface area. In this study, the internal surface of TNT was coated through a novel in-situ polymerization method with various polymers to alter the property and size of inner surface of the nanotubes, and then was embedded in the polyamide layer of the nanofiltration membrane. The modified nanotubes were supposed to act as the channels for water transport and reject the multivalent/monovalent ions; this phenomenon was more pronounced in the modified nanotubes because of the reduction in inner diameter. Fourier transform infrared spectroscopy, X-ray diffraction and Brunauer-Emmett-Teller analysis were used to characterize the unmodified/modified nanotubes. Furthermore, the membranes were synthesized by in-situ interfacial polymerization of trimesoyl chloride and m-phenylenediamine containing 0.05 wt% nanotubes; the performance of the fabricated membranes in terms of pure water flux (PWF), contact angle, feed flux and Na+ and Cu2+ rejections was studied. Generally, incorporation of the modified nanotubes improved the trade-off between the permeation and rejection. Among the fabricated membranes, the maximum PWF was 26.13 L m−2 h−1 for the membrane containing 0.05 wt% polystyrene modified TNT, 71.23% more than neat thin film membrane and without any significant change in the rejection; that can be related to the hydrophilicity of the nanotube and the formation of small cavities on the membrane surface. [ABSTRACT FROM AUTHOR]

Ballast water is a significant vector for the transport and introduction of aquatic organisms, microorganisms and chemical pollutants which impacts on ecosystems worldwide. In the study, ballast water from short- and long-range vessels with treatment systems was microbiologically evaluated in spring (April 20th) and summer (July 19th) and compared with waters of the main Police Seaport in the Odra River Estuary, southern Baltic Sea. All collected samples were evaluated for their physicochemical properties by standard methods. The number of individual groups of microorganisms was determined using the indirect culture method, according to the technique of inoculation of serial dilutions of samples of the examined waters. The results showed differences in the microorganisms in analysed samples. The phylogenetic analysis of bacteria recorded from the ballast water of short-range ships in spring showed the presence of six species of the genus Bordetella, while in summer four species of the genus Clostridium. In the ballast water of long-range ships, proteolytic bacteria pre-dominated in spring and halophilic bacteria in summer. In the summer period, eight species of bacteria were recorded, of which six belonged to the genus Clostridium. The ballast water treatment processes used on ships influence the composition of bacterial communities through selective recolonisation of water, which may transform bacterial functions as an important element of the marine food web. On the other hand, the presence of pathogenic bacterial species in the tested samples indicates improvement necessity of ballast water treatment systems used on vessels. [ABSTRACT FROM AUTHOR]

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Biopolymer-based films are hydrophilic biodegradable matrices that exhibit poor water vapour barrier. Ideally, water vapour permeability does not depend on the water vapour pressure gradient and film thickness. However, hydrophilic films interact with water and this affects the solubility and diffusion of water in the matrix. This may produce anomalies such as the dependence of permeability on the thickness and the water pressure gradient. In this work, the water transport through yeast biomass-based films, as an example of a biopolymeric matrix, was studied against changes in film thickness and water pressure gradients. Water sorption isotherms and water vapour permeability measurements allowed the evaluation of water solubility and diffusion as separate phenomena that contribute to permeability. Solubility and diffusion turned out to be strongly dependent on the water pressure gradient. Permeability revealed a non-linear behaviour as a function of pressure gradient, which was mainly due to the contribution of the water solubility. At all pressure gradients, the thickness increase produced a linear growth of the permeability, which was a consequence of the increase in diffusion. The thickness effect observed even at low water vapour pressures advised that, in addition to the effect of the matrix affinity to the water, the formation of a different structure produced at different thicknesses after casting must also be considered to explain the phenomenon. Results revealed the importance of both the assessment of environmental conditions and film thickness during end-use applications to optimize the performance of biopolymeric matrices. [ABSTRACT FROM AUTHOR]

Auxins are known to regulate xylem development in plants, but their effects on water transport efficiency are poorly known. Here we used tomato plants with the diageotropica mutation (dgt), which has impaired function of a cyclophilin 1 cis – trans isomerase involved in auxin signaling, and the corresponding wild type (WT) to explore the mutation's effects on plant hydraulics and leaf gas exchange. The xylem of the dgt mutant showed a reduced hydraulically weighted vessel diameter (D h) (24–43%) and conduit number (25–58%) in petioles and stems, resulting in lower theoretical hydraulic conductivities (K t); on the other hand, no changes in root D h and K t were observed. The measured stem and leaf hydraulic conductances of the dgt mutant were lower (up to 81%), in agreement with the K t values; however, despite dgt and WT plants showing similar root D h and K t, the measured root hydraulic conductance of the dgt mutant was 75% lower. The dgt mutation increased the vein and stomatal density, which could potentially increase photosynthesis. Nevertheless, even though it had the same photosynthetic capacity as WT plants, the dgt mutant showed a photosynthetic rate c. 25% lower, coupled with a stomatal conductance reduction of 52%. These results clearly demonstrate that increases in minor vein and stomatal density only result in higher leaf gas exchange when accompanied by higher hydraulic efficiency. [ABSTRACT FROM AUTHOR]

Introduction: The uterus and placenta transport water during pregnancy recognition signaling, conceptus implantation, and placental development/placentation. This is likely influenced by aquaporins (AQPs) in the reproductive tract. This study determined mRNA and cell-type specific expression of AQP 1, 5, 8, and 9 proteins in the porcine uterus and placenta.Methods: Porcine uteri and Chorioallantois were subjected to real-time PCR and immunofluorescence microscopy.Results: AQP1 mRNA was maximal by Day 25 in endometrium and remained stable thereafter. AQP1 mRNA did not change in chorioallantois. AQP1 protein localized to erythrocytes and endothelium of the endometrium and allantois, and to smooth muscle of the myometrium. AQP5 protein localized to apical and lateral surfaces of the chorionic epithelia of areolae, but mRNA did not change in chorioallantois. AQP8 mRNA was high in the endometrium from Days 15 through 60 of gestation, and protein localized to multiple cell types within the endometrium and chorioallantois. AQP9 mRNA was highest in the endometrium on Days 10, 12 and 25, but did not change in the chorioallantois. AQP9 protein localized to the apical surface of endometrial luminal epithelial cells during early pregnancy, with a shift towards the basal surface later. AQP9 protein was observed in the allantoic epithelium.Discussion: Results reveal pigs can potentially use AQP1, AQP5, AQP8, and AQP9 to transport water from the endometrial bloodstream to the allantoic bloodstream or allantoic fluid. The reverse is also possible and may explain the mechanism for changing volumes of allantoic fluid and hydration of allantoic connective tissues during pregnancy. [ABSTRACT FROM AUTHOR]

In this paper a dynamic membrane electrode assembly water transport model, based on the Finite Volume Method, is presented. The purpose of this paper is to provide an accessible and reproductible model capable of real time simulation. To this aim, a detailed explanation is provided regarding the equations and methods used to compute the physical-based fuel cell model. Additionally, the model is purposely developed using basic code (on Matlab™), to not be limited to a single programming language. Two phase water transport through multi-gaseous porous media (electrodes), interfacial transport, as well as diffusion, convection, and electro-osmosis within the polymer are considered. The main novelty relies in the restructuring of all equations into a single implicit system, which can iteratively be resolved through LU decomposition. This computationally efficient method allows the model to be capable of real-time simulation, by displaying the membrane water content profile evolution on a 3D figure. For nominal PEMFC operating conditions, a dry membrane reaches 35% of its final water concentration value after 2 s, and fully converges after 20 s. The final water content profile displays an 18% gradient (9 and 11 molecules per sulfonic acid sites on the anode and cathode sides, respectively). To calibrate and validate this model, mass transfer (flowmeter) and electrical (ohmmeter) methods have been applied. • Dynamic membrane electrode assembly water transport model, based on finite difference method. • Water transport equations and resolution process detailed, to aim for model reproducibility. • Restructuring of water transport equations into implicit equation system. • Iterative equation system resolution through LU decomposition, allowing for real time simulation. • 3-dimensional figures of Nafion™ hydration profile, to study its behavior. [ABSTRACT FROM AUTHOR]

Achiral 2‐hydroxy‐N‐(diphenylmethyl)acetamide (HNDPA) crystallizes in the P61 chiral space group as a hydrate, building up permeable chiral crystalline helical water channels. The crystallization‐driven chiral self‐resolution process is highly robust, with the same air‐stable crystalline form readily obtained under a variety of conditions. Interestingly, the HNDPA supramolecular helix inner pore is filled by a helical water wire. The whole edifice is mainly stabilized by robust hydrogen bonds involving the HNDPA amide bonds and CH...π interactions between the HNDPA phenyl groups. The crystalline structure shows breathing behavior, with completely reversible release and re‐uptake of water inside the chiral channel under ambient conditions. Importantly, the HNDPA channel is able to transport water very efficiently and selectively under biomimetic conditions. With a permeability per channel of 3.3 million water molecules per second in large unilamellar vesicles (LUV) and total selectivity against NaCl, the HNDPA channel is a very promising functional nanomaterial for future applications. [ABSTRACT FROM AUTHOR]

Summary: Proton exchange membrane fuel cells (PEMFCs) have garnered considerable attention for transportation applications owing to their high energy efficiency. Understanding their long‐term durability is essential because the performance deteriorates over time. The water transport characteristics of the gas diffusion layer (GDL), aged by inserting hydrogen peroxide solutions, are investigated. The dynamics of the water meniscus inside the GDL is visualized via synchrotron phase‐contrast radiography, and the temporal variations in the pressure are measured simultaneously. The pressure and time at breakthrough (BT) when the water firstly emerged from GDL were compared. The degraded GDL exhibits a larger BT pressure and requires a longer time to achieve the first water BT than the pristine GDL. Unlike the pristine GDL showing snap‐off patterns, water continuously penetrates the degraded GDL representing the piston‐like movement, and repetitive increases and decreases in the pressure are not observed. This difference represents the dominant transport mechanisms. GDL degradation induces the loss of polytetrafluoroethylene (PTFE), which is generally used for the effective transport of fuel and water. The PTFE loss reduces the hydrophobicity and pore size, which can increase the actual path length of the water flow. The increase in the BT time and BT pressure, as well as continuous transport, can disrupt fuel supply to chemical reaction sites, thereby deteriorating the PEMFC performance. [ABSTRACT FROM AUTHOR]

The remote North Patagonian region is a sparsely populated territory and a world famous tourist destination located on the leeward side of the Andes Mountains. Recent disasters triggered by various types of geoenvironmental hazards (including volcanic eruptions, mass-wasting processes and extreme weather events) heavily disrupted ground transport networks in a region with already limited territorial accessibilities. All these catastrophes prompted the need to evacuate or assist a number of secluded visitors, locals and livestock extemporaneously on board of coastguards and tourist passenger-ships from the shores of the many glacial lakes that make up part of the regional attraction. Despite the recurrence of these types of events, water evacuations in the region continue to be spontaneous, improvised and hazardous procedures. This contribution reconstructs and assesses a number of recent local-scale cases of lake evacuations and assistances from a number of Patagonian urban centers, rural areas and tourist sites. For each case study, we systematically elaborated on the prime components of an evacuation process, which enabled us to recognize key achievements, failures and conditioning factors for managing emergencies via water transport, most of them inherent to the studied region. Some of the complexities to emerge from case studies referred to: complex hazard-related scenarios; limited ground-based accessibilities and risk of isolation; various inter- and intra-organizational issues, incidental to natural reserves and tourist regions; a wide range of particular demographic features; and the availability and vulnerability of water transport resources. We suggested fundamental and replicable recommendations for developing water evacuation plans, also identifying forthcoming problems to solve in order to improve the management of emergencies through this alternative means of transport. [ABSTRACT FROM AUTHOR]

To alleviate water flooding in cathode electrodes of polymer electrolyte fuel cells (PEFCs), it is essential to design the optimum channel/electrode structure for rapid water removal. This study presented a novel hybrid structure with the channel hydrophilization and electrode perforation for accelerating the through-plane water discharge and demonstrated the effect of its structure on the water transports in the cathode channel and gas diffusion layer (GDL) of a working PEFC with optical and X-ray imaging. The results revealed that the hydrophilization of the channel walls encourages the through-plane water suction form the GDL to the channel. Furthermore, the electrode perforation promotes the in-plane water discharge from the fine porous media to the large penetration grooves and holes. The synergistic effect of these two water transports in the hybrid structure effectively alleviates the flooding in the porous layers and enhances the oxygen diffusibility, resulting in significant improvement of the cell performance.

In mice, the contraction of the ciliary muscle via the administration of pilocarpine reduces the zonular tension applied to the lens and activates the TRPV1-mediated arm of a dual feedback system that regulates the lens’ hydrostatic pressure gradient. In the rat lens, this pilocarpine-induced reduction in zonular tension also causes the water channel AQP5 to be removed from the membranes of fiber cells located in the anterior influx and equatorial efflux zones. Here, we determined whether this pilocarpine-induced membrane trafficking of AQP5 is also regulated by the activation of TRPV1. Using microelectrode-based methods to measure surface pressure, we found that pilocarpine also increased pressure in the rat lenses via the activation of TRPV1, while pilocarpine-induced removal of AQP5 from the membrane observed using immunolabelling was abolished by pre-incubation of the lenses with a TRPV1 inhibitor. In contrast, mimicking the actions of pilocarpine by blocking TRPV4 and then activating TRPV1 resulted in sustained increase in pressure and the removal of AQP5 from the anterior influx and equatorial efflux zones. These results show that the removal of AQP5 in response to a decrease in zonular tension is mediated by TRPV1 and suggest that regional changes to PH2O contribute to lens hydrostatic pressure gradient regulation.