Channel Pattern Research Articles

A Multi-Scale Thermal-Mechanical Numerical Method for Mini-Channel Heat Exchanger Subjected to Fluid Pressure Loads

Abstract This study proposes a novel multi-scale numerical method for thermal-mechanical analysis of mini-channel heat exchangers (MCHEs) under internal fluid pressure and temperature loads. The method comprises a macro-scale model for global analysis and a meso-scale model for detailed submodel analysis, specifically focusing on the internal fluid pressure effects within the MCHEs. The macroscopic model divides the MCHE into cover plate and homogenized regions subjected to pressure and temperature loads. To incorporate internal pressures into the homogenized MCHE model, mathematical equations are formulated to convert internal fluid pressures into equivalent strain loads. Additionally, a novel equivalent thermal expansion method is introduced, integrating internal fluid pressure loads by prescribing equivalent thermal expansion coefficients alongside spatially-varying nodal temperature fields within the MCHE. The meso-scale models with detailed channel patterns are assigned to specific portions of the homogenized region. The integration of the mesoscale model into the macroscopic framework is achieved through the application of the submodel method. Comparisons between the equivalent and actual MCHE models show that the proposed equivalent method can provide accurate predictions for thermal-mechanical deformations and stresses, and significantly reduce the computational expenses.

PIEZO1 mediates matrix stiffness-induced tumor progression in kidney renal clear cell carcinoma by activating the Ca2+/Calpain/YAP pathway

ObjectiveThe significance of physical factors in the onset and progression of tumors has been increasingly substantiated by a multitude of studies. The extracellular matrix, a pivotal component of the tumor microenvironment, has been the subject of extensive investigation in connection with the advancement of KIRC (Kidney Renal Clear Cell Carcinoma) in recent years. PIEZO1, a mechanosensitive ion channel, has been recognized as a modulator of diverse physiological processes. Nonetheless, the precise function of PIEZO1 as a transducer of mechanical stimuli in KIRC remains poorly elucidated. MethodsA bioinformatics analysis was conducted using data from The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC) to explore the correlation between matrix stiffness indicators, such as COL1A1 and LOX mRNA levels, and KIRC prognosis. Expression patterns of mechanosensitive ion channels, particularly PIEZO1, were examined. Collagen-coated polyacrylamide hydrogel models were utilized to simulate varying stiffness environments and study their effects on KIRC cell behavior in vitro. Functional experiments, including PIEZO1 knockdown and overexpression, were performed to investigate the molecular mechanisms underlying matrix stiffness-induced cellular changes. Interventions in the Ca2+/Calpain/YAP Pathway were conducted to evaluate their effects on cell growth, EMT, and stemness characteristics. ResultsOur findings indicate a significant correlation between matrix stiffness and the prognosis of KIRC patients. It is observed that higher mechanical stiffness can facilitate the growth and metastasis of KIRC cells. Notably, we have also observed that the deficiency of PIEZO1 hinders the proliferation, EMT, and stemness characteristics of KIRC cells induced by a stiff matrix. Our study suggests that PIEZO1 plays a crucial role in mediating KIRC growth and metastasis through the activation of the Ca2+/Calpain/YAP Pathway. ConclusionThis study elucidates a novel mechanism through which the activation of PIEZO1 leads to calcium influx, subsequent calpain activation, and YAP nuclear translocation, thereby contributing to the progression of KIRC driven by matrix stiffness.

Distinct Neuron Types Contribute to Hybrid Auditory Spatial Coding.

Neural decoding is a tool for understanding how activities from a population of neurons inside the brain relate to the outside world and for engineering applications such as brain-machine interfaces. However, neural decoding studies mainly focused on different decoding algorithms rather than different neuron types which could use different coding strategies. In this study, we used two-photon calcium imaging to assess three auditory spatial decoders (space map, opponent channel, and population pattern) in excitatory and inhibitory neurons in the dorsal inferior colliculus of male and female mice. Our findings revealed a clustering of excitatory neurons that prefer similar interaural level difference (ILD), the primary spatial cues in mice, while inhibitory neurons showed random local ILD organization. We found that inhibitory neurons displayed lower decoding variability under the opponent channel decoder, while excitatory neurons achieved higher decoding accuracy under the space map and population pattern decoders. Further analysis revealed that the inhibitory neurons' preference for ILD off the midline and the excitatory neurons' heterogeneous ILD tuning account for their decoding differences. Additionally, we discovered a sharper ILD tuning in the inhibitory neurons. Our computational model, linking this to increased presynaptic inhibitory inputs, was corroborated using monaural and binaural stimuli. Overall, this study provides experimental and computational insight into how excitatory and inhibitory neurons uniquely contribute to the coding of sound locations.

Organizational Communication Patterns in The Management of Mental Development of Kodam II Sriwijaya in The Digital Era

Mental coaching is one of the methods to shape the mentality of Army soldiers to always act based on high morals, enthusiasm, and awareness, with the aim of forming commendable and responsible morals in living life. This research aims to analyze the pattern of organizational communication in the management of mental development of soldiers through planning, organization, implementation, and supervision, as well as what media are used in each process in Kodam II Sriwijaya. This research uses a qualitative approach with descriptive methods. Data collection techniques were conducted through interviews and documentation, while data analysis techniques include data reduction, data presentation, and conclusion drawing or verification. This research also uses source triangulation to validate the data. The results showed that in the Planning and Organizing stages, the Wheel Pattern and Chain Pattern communication patterns were used, where the leader was central in determining work plans, instructions, reports, and organizational structures. At the Implementation stage, the patterns used are Wheel Pattern and All Channel Pattern, with new communication media such as WhatsApp as the main tool. At the Monitoring stage, the Wheel Pattern remains dominant, where the leader acts as the center of evaluation in receiving and sending messages. The implication of this research is the important role of structured communication and the use of new media in the management of soldiers' mental development, which can improve the effectiveness of organizational communication and soldiers' performance.

Grain size and sediment load control on channel migration patterns of the Ghaghara river from Faizabad to Deoria, Ganga plain, India

Grain size and sediment load control on channel migration patterns of the Ghaghara river from Faizabad to Deoria, Ganga plain, India

Influence of Typical Regional Land Use/Landscape Pattern on Water TN of the Upper Yellow River

This study aimed to explore the relationship between land use landscape pattern and water quality in the upstream of the Gansu water conservation, water and soil erosion, and ecological fragile areas. Based on the land use data and water quality monitoring section in 2020 in the 200 m, 500 m, 1 km, 2 km, 50 km, and 10 km riparian buffer area, the single-factor index evaluation method, random forest regression model, and BP neural network were used to quantify the response relationship between land use and landscape pattern of the upper Yellow River in Gansu province and water quality index and to carry out the basin water quality prediction based on land use landscape index data. The results showed that： ① through the single-factor index method, the major indicators of the total nitrogen （TN） in July and September, dissolved oxygen （DO）, permanganate index, ammonia nitrogen （NH4+ -N）, total phosphorus （TP）, and other surface indexes met the surface water environment class Ⅲ water quality standard. ② The random forest regression model was used to analyze the influence of land use and landscape index on TN, and the difference in TN in different typical areas was obtained. The land use types with the highest influence on the TN index in water conservation areas, soil and soil erosion areas, and ecological fragile areas were cultivated land, grassland, and construction land, respectively. ③ The BP neural network was used to predict the water quality index based on different typical areas of land use landscape index. The result of water conservation areas was good, the error rate between the predicted value and the actual value was below 10%, and the prediction accuracy was high. The study showed that water quality prediction based on land use and landscape index/water quality quantitative relationship model had a good water quality prediction effect.

Design of nature-inspired patterns on knitted fabrics for directional transportation of sweat and study of their performances

The human body in a hot environment or during intense training will sweat a lot. Traditional cotton fabrics are soft and breathable, but they tend to absorb moisture easily and evaporate it slowly, which makes people feel cold and wet. Sweat staying on fabrics for a long time could also cause bacteria to grow. Thus, it is necessary to transport the excessive sweat from the gathering section to the collection points along the surface paths in time to minimize such problems. The mechanism of directional water transport of desert beetles, cacti, nepenthes, and river meanders was referenced in this paper. The paths in dot, tree, V-shape, and river meander patterns were designed and manufactured from the inspiration of these natural architectures. The paths were coated on the surfaces of selected knitted fabrics with different structures through a one-step coating process. The optimal recipe of hydrophobic solution was determined when 0.1 g hydroxyethyl-cellulose (HEC) was added into MS-S002 solution. The results showed that sweat movement is mainly influenced by FL, FWD, FG, and knitted structure. The continuous and enclosed paths such as tree and river contribute to a better sweat moving track than those of dot and V-shape ones. Terry structure is more suitable for surface sweat transport than plain and pique. The highest movement speed of the terry structure with a tree pattern reaches 0.43 cm/s, followed by that of the terry structure with river pattern 0.35 cm/s. The coated fabrics also have ideal moisture and air permeability for wearing.

Study of the Flow Characteristics of Pumped Media in the Confined Morphology of a Ferrofluid Pump With Annular Microscale Constraints

Abstract The driving mechanism of ferrofluid micropumps under the constraints of an annular microscale morphology is not fully understood. The gap between microfabrication technology and the fundamental theory of microfluidics has become a substantial obstacle to the development and application of ferrofluid micropumps. In this study, we first theoretically analyzed the Knudsen numbers of millimeter-scale microfluids using Jacobson's molecular hard sphere model, obtaining the initial conclusion that liquid flow conforms to the continuum hypothesis in geometric morphologies with characteristic dimensions greater than 7 × 10−8 m. Subsequently, using a microscopic lens combined with the particle image velocimetry optical measurement method, the flow patterns in millimeter-scale annular flow channels were captured and we observed wall slip phenomena in which the slip length of the millimeter-scale channel approached the micron level. The slip velocity and flowrate through the cross section of the microscale channel followed a logarithmic function relationship and could be divided into rapid growth, slow growth, and stable stages. As the characteristic scale of the channel was further reduced, the linear relationship between the slip velocity and cross-sectional flowrate in the rapid growth stage was broken, and the nonlinear relationship approximated an exponential function. Finally, a theoretical model for the flow behavior of the driving fluid in a ferrofluid micropump was established using slip boundary conditions. The flow patterns in microscale ring flow under slip conditions conformed to a quadratic function.

Efisiensi Pemasaran Karet Di Kabupaten Ogan Ilir Sumatera Selatan

The rubber commodity in Ogan Ilir Regency plays an important role in increasing family income, but currently, the income of rubber farmers is still relatively low because farmers are still traditional in their marketing, causing the prices received by farmers to be low. The objectives of this study are to 1) Identify the functions of rubber marketing institutions in Ogan Ilir Regency, 2) Analyze the efficiency of rubber marketing in Ogan Ilir Regency.. Sampling was carried out randomly. 75 samples were used in this research, with a population of rubber farmers, namely 236 farmers in Tanjung Batu District and 254 in Payaraman District. Locations were chosen purposively based on the same considerations: the subdistricts and villages that produce the largest rubber production. Data collection uses cross-section data. Rubber marketing efficiency is analyzed using marketing margin, farmer's share, profit to cost ratio and the Data Envelopment Analysis (DEA) model. The research results show that rubber farmers in Ogan Ilir Regency use three marketing channel patterns. Based on the analysis of rubber marketing efficiency, it is recommended that rubber farmers in Ogan Ilir Regency use marketing channel 1, namely farmers-UPPB-factories and marketing channel 3, namely farmers-wholesalers-factories.

Determinan Yang Memengaruhi Pemilihan Saluran Pemasaran Kopi Robusta Di Kabupaten Malang

The demand for coffee in Malang Regency by determining the quantity of commodities is very dependent on the marketing subsystem. Robusta coffee marketing channels in Malang Regency include marketing institutions, namely small traders, sub-district collectors and large traders. Coffee marketing is dominated by small traders. This research aims to analyze the determinants that influence the choice of marketing channels for Robusta coffee in Malang Regency. The location of this research was carried out in two villages, namely Srimulyo Village and Sukodono Village, Kec. Dampit, Kab. Poor. The respondents in this research were Robusta coffee farmers in two villages in a total of 60 respondents. Marketing agency respondents were then determined using snowball sampling techniques. Snowball sampling method by collecting data based on information from previous respondents based on existing marketing patterns in Malang Regency. This research uses multinomial logit analysis by determining efficient marketing channels as a reference variable. Based on the results of marketing channel analysis, it was found that there are 5 marketing channel patterns. Marketing channel 1 consists of 27 farmers and the largest channel choice is 45%, while the results of the marketing efficiency analysis show that channel 5, namely direct farmers to wholesalers, is the most efficient. Marketing channel 5 consists of 11 farmers with a percentage of 18.3%. The results of the research show that 3 variables influence the choice of marketing channels, namely production volume, farming experience, and education level. Suggestions from research for extension workers and local governments need to assist farmers regarding financing and coffee market information so that marketing channel choices are more varied.

The influence of spin-spin interaction on high partial wave Feshbach resonance in ultracold 23Na -87Rb system.

In this paper, we investigate the Feshbach resonances of high partial waves and the influence of spin-spin (S-S) interaction on ultracold scattering processes. Taking the Na23- Rb87 system as an example, we plot the variations of weakly bound state energy and elastic scattering cross section with magnetic field and with collision energy. We find that the number of splittings in high partial wave Feshbach resonances does not strictly conform to the expected l + 1 (l is rotational angular momentum), and the deviation is attributed to the influence of bound states in other channels coupled by S-S interaction. For different ml (the projection of l on the external magnetic field direction), the effects of S-S interaction lead to different scattering patterns in the incident channels. These results reveal the complex features of ultracold scattering processes in high partial waves caused by S-S interaction.

Ultrasound pulse repetition frequency preferentially activates different neuron populations independent of cell type

Objective. Transcranial ultrasound (US) stimulation serves as an external input to a neuron, and thus the evoked response relies on neurons' intrinsic properties. Neural activity is limited to a couple hundred hertz and often exhibits preference to input frequencies. Accordingly, US pulsed at specific physiologic pulse repetition frequencies (PRFs) may selectively engage neurons with the corresponding input frequency preference. However, most US parametric studies examine the effects of supraphysiologic PRFs. It remains unclear whether pulsing US at different physiologic PRFs could activate distinct neurons in the awake mammalian brain.Approach. We recorded cellular calcium responses of individual motor cortex neurons to US pulsed at PRFs of 10, 40, and 140 Hz in awake mice. We compared the evoked responses across these PRFs in the same neurons. To further understand the cell-type dependent effects, we categorized the recorded neurons as parvalbumin positive fast spiking interneurons or putative excitatory neurons and analyzed single-cell mechanosensitive channel expression in mice and humans using the Allen Brain Institute's RNA-sequencing databases.Main results. We discovered that many neurons were preferentially activated by only one PRF and different PRFs selectively engaged distinct neuronal populations. US-evoked cellular calcium responses exhibited the same characteristics as those naturally occurring during spiking, suggesting that US increases intrinsic neuronal activity. Furthermore, evoked responses were similar between fast-spiking inhibitory neurons and putative excitatory neurons. Thus, variation in individual neuron's cellular properties dominates US-evoked response heterogeneity, consistent with our observed cell-type independent expression patterns of mechanosensitive channels across individual neurons in mice and humans. Finally, US transiently increased network synchrony without producing prolonged over-synchronization that could be detrimental to neural circuit functions.Significance. These results highlight the feasibility of activating distinct neuronal subgroups by varying PRF and the potential to improve neuromodulation effects by combining physiologic PRFs.

Lobish: Symbolic Language for Interpreting Electroencephalogram Signals in Language Detection Using Channel-Based Transformation and Pattern.

Electroencephalogram (EEG) signals contain information about the brain's state as they reflect the brain's functioning. However, the manual interpretation of EEG signals is tedious and time-consuming. Therefore, automatic EEG translation models need to be proposed using machine learning methods. In this study, we proposed an innovative method to achieve high classification performance with explainable results. We introduce channel-based transformation, a channel pattern (ChannelPat), the t algorithm, and Lobish (a symbolic language). By using channel-based transformation, EEG signals were encoded using the index of the channels. The proposed ChannelPat feature extractor encoded the transition between two channels and served as a histogram-based feature extractor. An iterative neighborhood component analysis (INCA) feature selector was employed to select the most informative features, and the selected features were fed into a new ensemble k-nearest neighbor (tkNN) classifier. To evaluate the classification capability of the proposed channel-based EEG language detection model, a new EEG language dataset comprising Arabic and Turkish was collected. Additionally, Lobish was introduced to obtain explainable outcomes from the proposed EEG language detection model. The proposed channel-based feature engineering model was applied to the collected EEG language dataset, achieving a classification accuracy of 98.59%. Lobish extracted meaningful information from the cortex of the brain for language detection.

Multi-Dimensional Modelling of Bioinspired Flow Channels Based on Plant Leaves for PEM Electrolyser

The Polymer Electrolyte Membrane Water Electrolyser (PEMWE) has gained significant interest among various electrolysis methods due to its ability to produce highly purified, compressed hydrogen. The spatial configuration of bipolar plates and their flow channel patterns play a critical role in the efficiency and longevity of the PEM water electrolyser. Optimally designed flow channels ensure uniform pressure and velocity distribution across the stack, enabling high-pressure operation and facilitating high current densities. This study uses flow channel geometry inspired by authentic vine leaf patterns found in biomass, based on various plant leaves, including Soybean, Victoria Amazonica, Water Lily, Nelumbo Nucifera, Kiwi, and Acalypha Hispida leaves, as a novel channel pattern to design a PEM bipolar plate with a circular cross-section area of 13.85 cm2. The proposed bipolar design is further analysed with COMSOL Multiphysics to integrate the conservation of mass and momentum, molecular diffusion (Maxwell–Stefan), charge transfer equations, and other fabrication factors into a cohesive single-domain model. The simulation results showed that the novel designs have the most uniform velocity profile, lower pressure drop, superior pressure distribution, and heightened mixture homogeneity compared to the traditional serpentine models.

Experimental study and infrared detector application research of micro miniature refrigerators

The MMR（Micro Miniature Refrigerator）is a novel Joule-Thomson cryocooler manufactured by micro-machining technologies, its axial length is significantly shorter than traditional Joule-Thomson cryocoolers commonly employed in infrared detectors. MMRs can greatly reduce the size of infrared detectors upon successful implementation. However, contemporary MMR products encounter challenges such as relatively low cool-down rates, cooling power, and structural strength. To address these issues and enhance the cool-down performance of the MMR for effective application in infrared detectors, a calculation model describing flow and heat transfer besides working characteristics of the MMR is proposed and verified. MMR prototypes are fabricated and experimentally studied. Building upon theoretical analysis and experimental findings cooling performance enhancement methods including transitioning the MMR material from glass to metal and modifying the structure and channel patterns of the MMR are introduced, the cooling performance of the MMR is thus greatly improved. Furthermore, an integrated design incorporating an MMR into an infrared detector is proposed, the axial length of this infrared detector is reduced by 65.3 % compared to conventional infrared detectors. And the MMR is further enhanced to adapt the working conditions in infrared detectors, 60.9 MPa working pressure and 38 s cool-down time is achieved, the cool-down requirements of infrared detectors is satisfied. Notably, the proposed MMR and infrared detector design in this paper exhibit technical advantages over similar products reported in the literature.

Mechanisms and Morphological Time Scales of Avulsed Channel Process on the Modern Yellow River Delta

AbstractThe modern Yellow River Delta (YRD) has witnessed frequent channel avulsions followed by the morphological processes of “wandering‐ short‐lived braiding ‐merging” in history. However, process‐based investigation and relevant physics behind these processes remain poorly constrained. The present study complements the understanding for this evolution through numerical experiments. This is achieved by applying a two‐dimensional (2‐D) depth‐averaged fully coupled morphodynamic model that considers the feedbacks of sediment‐laden flow and bed deformation to a schematized fan‐shaped YRD. Under an uneven bed of uniform sediment, the avulsed processes of “wandering‐ short‐lived braiding ‐merging” during new channel routing on the YRD are satisfactorily reproduced by the present modelling in terms of the time evolution of planar channel pattern and channel length. Moreover, the mechanisms of the avulsed evolution have been elucidated through factor analysis on delta slope, incoming flow‐sediment conditions and artificial trenching, etc. It is suggested that morphological stability could be reached when a single meandering channel is finally sustained, of which the time scale is 4–8 years echoing the documented data of abandoned channels on the YRD. In addition, quantitative criteria have been advocated to help distinguishing the sub‐stages of the avulsed evolution together with the characteristic pattern judgement. Based on the above, implications for the YRD management are discussed.

Research on CO Migration Patterns in Shallowly Buried Coal Seam Composite Goafs.

To address the issue of CO exceedance in the close-range composite goaf, this paper focuses on the composite goaf of the Shaping Mine as the research subject and investigated the migration dynamics of CO within shallowly buried composite goaf areas. Sulfur hexafluoride gas (SF6) tracer experiments were conducted at the 13103 working face in Shaping Mine to assess surface fissures and air leakage, yielding insights into the distribution patterns of air leakage channels and facilitating the identification of critical areas for channel sealing. Programmed heating and oxidation experiments were conducted on coal seams 8# and 13# to determine the CO generation patterns during coal oxidation. The results show that higher concentrations of O2 corresponded to elevated CO production at equivalent temperatures. Subsequent data analysis unveiled exponential relationships between the O2 consumption rate and CO production rate within the goaf area, offering a theoretical framework for understanding CO migration patterns. Through numerical simulations, the study analyzed the CO migration patterns in the composite goaf area, observing downward diffusion of CO emanating from coal oxidation in the overlying goaf areas followed by dispersion toward the working face and roadways. Driven by airflow dynamics, CO accrued in the return air corner of the working face. Building upon these insights, comprehensive CO management strategies were implemented, resulting in sustained reductions of temperatures and CO concentrations to safe levels within the original high-temperature, high-concentration CO zones. Notably, CO concentrations at the return air corner of the working face continued to decline over the management period, reaching below 24 ppm within 10 to 15 days, highlighting the effectiveness of the management measures in ensuring safe underground production.

Channel changes during and after extreme floods in two catchments of the Northern Apennines (Italy)

The Nure and Trebbia catchments were affected by an extreme flood event on 13-14th September 2015. This study investigates the morphological responses to the flood of the Nure and Trebbia rivers and 18 tributaries with the aims to: i) quantify channel changes in width and pattern; (ii) identify the morphological and hydrological factors which might have driven channel response; (iii) quantify channel changes which have occurred after the flood event.Channel changes were characterized by field surveys and geomorphological analysis of multi-temporal orthophotos acquired before (2011), immediately after the flood (2015) and in 2020.In the tributaries, reach-scale channel widths after the flood reached up to 15 times their pre-flood values, whereas in the main channels the post/pre-flood width ratio attained a maximum value of 4. Augmented channel width in the main rivers was mostly associated with banks and islands erosion, whereas in the tributaries it was also due to deposition of coarse sediments onto the former floodplains. Islands were swept away in the main channels while both island erosion and formation occurred in the tributaries. In terms of channel pattern, pre-flood single-thread reaches displayed mainly multi-thread morphologies after the flood, mostly in response to a sudden input of coarse sediment supply. In the 5 yr following the flood, channels slightly narrowed but still remained wider than in 2011. The narrower reaches before the flood resulted to be the most sensitive to changes even some years after the flood.Statistical analyses between the channel width changes and a series of variables showed significant positive correlations with confinement index, channel slope, and the local storm rainfall depth. This study confirms how channel widening during large floods – usually neglected in flood hazard mapping and river basin management – is a very important process which must be considered in flood hazard assessment in mountain rivers.

Decoding the complex fluvial-lacustrine sedimentary interactions: Insights from the Neogene Guantao Formation in the Bohai Bay Basin and Modern Poyang Lake, China

Small-scale lake level variations lead to significant landward/basinward shifts in the depositional system, thereby facilitating the widespread development of fluvial-lacustrine interaction sedimentary systems. Such systems are commonly found in low-gradient shallow-water continental down-warped lacustrine basins, which are favorable for the formation of composite reservoir-caprock assemblages. Nevertheless, our understanding of the sedimentary stratigraphy of the Neogene Guantao Formation remains limited due to the complex and variable spatial and temporal associations between fluvial and lacustrine deposits. Integrated analysis of the geomorphology and stratigraphy of the modern Poyang Lake Basin and ancient Bohai Bay Basin (BBB) allows us to develop a process-based fluvial-lacustrine interaction model of shallow-water depositional system. Three physiographic zones are identified based on seasonal lake shoreline migration during a certain geological sequence unit, namely fluvial-dominated zone (FDZ), fluvial-lacustrine interaction zone (FLIZ) and lacustrine-dominated zone (LDZ), respectively. The FDZ is always above the maximum lake shoreline without affection by lake basin water body and is characterized by channelized dendritic pattern of distributary channels with positive rhythmic cycles. The FLIZ is a dynamic interaction region between the maximum lake shoreline and the lowest lake shoreline. Reticular distributary channels, delta front and prodelta/lake deposits vertically superimpose and dominate the system that is featured by complex sandbody, stacked positive and negative rhythms and strong water body segmentation. The LDZ, away from the fluvial effect, was identified below the lowest lake shoreline exhibiting polycentric sheet water body, dominated by lacustrine mudstone interspersed with thin sheet-like sandstone. These results shed light on the spatial and temporal sedimentary heterogeneity in such dynamic fluvial-lacustrine interaction systems. The proposed fluvial-lacustrine interaction model may serve as a valuable analogue for identifying sedimentary types and predicting sandstone reservoirs in similar shallow-water settings ranging from continental down-warped lacustrine basins to cratonic basins, and fault-depression basin gentle-slope belts.

Hydromorphological degradation modifies long-term macroinvertebrate responses to water quality and climate changes in lowland rivers

Due to decades of persistent anthropogenic pressures, lowland rivers represent one of the most severely impaired habitats in Europe. Despite improved water quality, novel stressors, particularly climate change, are emerging with most lowland rivers suffering from past hydromorphological degradation. We aim to elucidate how such degradation alters the biological response in multiple-stressor environments, as this has rarely been considered in studies documenting long-term development of anthropogenically impacted rivers. Here, benthic macroinvertebrates, water quality and hydroclimatic variables were monitored over a period of two decades in nine of the largest Czech rivers. Detailed data on hydromorphological degradation allowed us to track distinct patterns in rivers with high and low levels of degradation. Temporal changes in environmental variables showed similar patterns in both site groups, characterised by reduced organic and nutrient pollution but increased hydroclimatic and salinity stress. 150 % increase in total abundance, especially in abundance and richness of sediment-dwelling and non-native taxa was found in both site groups. While the increase in abundance was due to improved water quality and rising water temperature, the longer duration of minimal flows had a negative effect on species richness, hampering species gain particularly at highly degraded sites. Our results provide novel evidence that degree of hydromorphological degradation modifies long-term macroinvertebrate responses to anthropogenic pressures. Less degraded sites displayed several favourable changes, such as 27 % increase in total and 23 % increase in potamal indicator richness, and stabilisation of the assemblages with few functional changes. In contrast, highly degraded sites experienced 9 % reduction in evenness, 235 % increase in proportion of non-native taxa and functional reorganisation, changes congruent with continuous deterioration. While overall water quality at studied sites has improved, consequences of climate change and high degree of hydromorphological degradation limit biotic recovery in multiple-stressor lowland rivers.