Channel Changes Research Articles

Modeling the morphological response of gravel–bed rivers subject to repeated sediment bypass tunnel operations

Introduction: Sediment bypass tunnels (SBTs) are operated during floods to re-establish sediment continuity past dams with the ultimate goal of decreasing accumulation in reservoirs. Depending on the location of the intake structure and operational conditions, SBTs may release either bed load-laden or bed load-free flows in the form of sudden floods (pulses). When evaluating the impacts of SBTs, the traditional approach has been to monitor channel changes in the years following project completion. However, by the time these impacts become evident, mitigation is challenging.Methods: This research adopts a forward-thinking methodology, emphasizing the prediction of potential impacts during the project’s early planning stages. We use a one-dimensional morphodynamic model to forecast the potential morphological response of a gravel-bed river with an idealized geometry to a series of SBT operations characteristic of projects in the Swiss Alps.Results: The morphological response of the downstream reach over the medium to long term is influenced by the alternating pattern of bed load-laden and bed load-free flow releases. This pattern is instrumental in forming a transition region near the SBT outlet hydrograph boundary layer (HBL).Discussion: Within the (HBL), fluctuations in bed elevation and slope are localized, while variations in grain-size distribution persist throughout the downstream region.

Motor learning changes the axon initial segment of the spinal motoneuron.

We are studying the mechanisms of H-reflex operant conditioning, a simple form of learning. Modelling studies in the literature and our previous data suggested that changes in the axon initial segment (AIS) might contribute. To explore this, we used blinded quantitative histological and immunohistochemical methods to study in adult rats the impact of H-reflex conditioning on the AIS of the spinal motoneuron that produces the reflex. Successful, but not unsuccessful, H-reflex up-conditioning was associated with greater AIS length and distance from soma; greater length correlated with greater H-reflex increase. Modelling studies in the literature suggest that these increases may increase motoneuron excitability, supporting the hypothesis that they may contribute to H-reflex increase. Up-conditioning did not affect AIS ankyrin G (AnkG) immunoreactivity (IR), p-p38 protein kinase IR, or GABAergic terminals. Successful, but not unsuccessful, H-reflex down-conditioning was associated with more GABAergic terminals on the AIS, weaker AnkG-IR, and stronger p-p38-IR. More GABAergic terminals and weaker AnkG-IR correlated with greater H-reflex decrease. These changes might potentially contribute to the positive shift in motoneuron firing threshold underlying H-reflex decrease; they are consistent with modelling suggesting that sodium channel change may be responsible. H-reflex down-conditioning did not affect AIS dimensions. This evidence that AIS plasticity is associated with and might contribute to H-reflex conditioning adds to evidence that motor learning involves both spinal and brain plasticity, and both neuronal and synaptic plasticity. AIS properties of spinal motoneurons are likely to reflect the combined influence of all the motor skills that share these motoneurons. KEY POINTS: Neuronal action potentials normally begin in the axon initial segment (AIS). AIS plasticity affects neuronal excitability in development and disease. Whether it does so in learning is unknown. Operant conditioning of a spinal reflex, a simple learning model, changes the rat spinal motoneuron AIS. Successful, but not unsuccessful, H-reflex up-conditioning is associated with greater AIS length and distance from soma. Successful, but not unsuccessful, down-conditioning is associated with more AIS GABAergic terminals, less ankyrin G, and more p-p38 protein kinase. The associations between AIS plasticity and successful H-reflex conditioning are consistent with those between AIS plasticity and functional changes in development and disease, and with those predicted by modelling studies in the literature. Motor learning changes neurons and synapses in spinal cord and brain. Because spinal motoneurons are the final common pathway for behaviour, their AIS properties probably reflect the combined impact of all the behaviours that use these motoneurons.

Calcium channel inhibitor and extracellular calcium improve aminoglycoside-induced hair cell loss in zebrafish.

Aminoglycosides are commonly used antibiotics for treatment of gram-negative bacterial infections, however, they might act on inner ear, leading to hair-cell death and hearing loss. Currently, there is no targeted therapy for aminoglycoside ototoxicity, since the underlying mechanisms of aminoglycoside-induced hearing impairments are not fully defined. This study aimed to investigate whether the calcium channel blocker verapamil and changes in intracellular & extracellular calcium could ameliorateaminoglycoside-induced ototoxicity in zebrafish. The present findings showed that a significant decreased number of neuromasts in the lateral lines of zebrafish larvae at 5days' post fertilization after neomycin (20μM) and gentamicin (20mg/mL) exposure, which was prevented by verapamil. Moreover, verapamil (10-100μM) attenuated aminoglycoside-induced toxic response in different external calcium concentrations (33-3300μM). The increasing extracellular calcium reduced hair cell loss from aminoglycoside exposure, while lower calcium facilitated hair cell death. In contrast, calcium channel activator Bay K8644 (20μM) enhanced aminoglycoside-induced ototoxicity and reversed the protective action of higher external calcium on hair cell loss. However, neomycin-elicited hair cell death was not altered by caffeine, ryanodine receptor (RyR) agonist, and RyR antagonists, including thapsigargin, ryanodine, and ruthenium red. The uptake ofneomycininto hair cells was attenuated by verapamil and under high external calcium concentration. Consistently, the production of reactive oxygen species (ROS) in neuromasts exposed to neomycin was also reduced by verapamil and high external calcium. Significantly, zebrafish larvae when exposed to neomycin exhibited decreased swimming distances in reaction to droplet stimulus when compared to the control group. Verapamil and elevated external calcium effectively protected the impaired swimming ability of zebrafish larvae induced by neomycin. These data imply that prevention of hair cell damage correlated with swimming behavior against aminoglycoside ototoxicity by verapamil and higher external calcium might be associated with inhibition of excessive ROS production andaminoglycoside uptake through cation channels. These findings indicate that calcium channel blocker and higher external calcium could be applied to protect aminoglycoside-induced listening impairments.

The domino effect of drug distribution channels on the management of chronicity.

Drug distribution channels affect all actors in the drug supply chain: healthcare institutions, healthcare professionals, patients, pharmacies, pharmaceutical companies and distributors. They should be redesigned in line with the new proximity care model planned in the Pnrr and DM 77, while avoiding a negative domino effect on the management of chronic diseases. A guide recently published by the MaCroScopio project is useful to shed light on this issue and to understand the relationship between the distribution channels present in Italy (distribuzione diretta - DD; distribuzione per conto - Dpc; distribuzione convenzionata) and the management of chronic diseases. Analysis of OsMed data showed that the majority of medicines dispensed in DD and Dpc are for chronic patients; therefore, a change in distribution channels inevitably affects chronicity management and could lead to increased expenditure. It is necessary to evaluate the transfer of drugs from one channel to another on a case-by-case basis according to the specifics of each drug. Proximity care reform requires a redesign of drug distribution channels, but this must be done with respect to the clinical, social and economic sustainability of the system.

Dynamic conformational changes of acid-sensing ion channels in different desensitizing conditions

Acid-sensing ion channels (ASICs) are proton-gated cation channels that contribute to fast synaptic transmission and have roles in fear conditioning and nociception. Apart from activation at low pH, ASIC1a also undergoes several types of desensitization, including acute desensitization, which terminates activation; steady-state desensitization, which occurs at sub-activating proton concentrations and limits subsequent activation; and tachyphylaxis, which results in a progressive decrease in response during a series of activations. Structural insights from a desensitized state of ASIC1 have provided great spatial detail, but dynamic insights into conformational changes in different desensitizing conditions are largely missing. Here, we use electrophysiology and voltage-clamp fluorometry to follow the functional changes of the pore along with conformational changes at several positions in the extracellular and upper transmembrane domain via cysteine-labeled fluorophores. Acute desensitization terminates activation in wild type, but introducing an N414K mutation in the β11-12 linker of mouse ASIC1a interfered with this process. The mutation also affected steady-state desensitization and led to pronounced tachyphylaxis. Although the extracellular domain of this mutant remained sensitive to pH and underwent pH-dependent conformational changes, these conformational changes did not necessarily lead to desensitization. N414K-containing channels also remained sensitive to a known peptide modulator that increases steady-state desensitization, indicating that the mutation only reduced, but not precluded, desensitization. Together, this study contributes to our understanding of the fundamental properties of ASIC1a desensitization, emphasizing the complex interplay between the conformational changes of the extracellular domain and the pore during channel activation and desensitization.

Design of Deep Learning Acoustic Sonar Receiver with Temporal/ Spatial Underwater Channel Feature Extraction Capability

In this study, deep learning network technology is employed to solve the problem of rapid changes in underwater channels. The modulation techniques employed are frequency-shift keying (FSK) and the BELLHOP module of MATLAB; they are used to create water with multipath, Doppler shifts, and additive Gaussian white noise such that underwater acoustic receiving signals simulating the actual ocean environment can be obtained. The southwest coastal area of Taiwan is simulated in the manuscript. The results reveal that optimizing the environment by using the virtual time reversal mirror (VTRM) technique can generally mitigate the bit error rates (BERs) of the deep learning network’s model receiver and traditional demodulation receiver. Lastly, seven deep learning networks are deployed to demodulate the FSK signals, and these approaches are compared with traditional demodulation techniques to determine the deep learning network techniques that are most suitable for marine environments.

Experiments of Failure and Damage in ITO-Coated PC/FPC with ACF Bonding due to Bending Fatigue

Anisotropic conductive film (ACF) is frequently used in the packaging manufacture for fine-pitch conductivity and interconnection, maintaining the electrical and mechanical connections between micro-electrodes. A key determinant of good conductivity is the deformation, fatigue, and breakage of conductive particles within the ACF packaging. This study aims to measure the resistance changes of specific conductive channels and observe the microscopic fatigue damage of compressed ACF conductive particles through the fabrication of Flex Printed Circuits (FPC) / Indium Tin Oxide-coated Polycarbonate (ITO-coated PC) specimens and the setup of bending experiments. The results show that the deformation, fatigue, and breakage of conductive particles will quantitatively affect electrical conductivity performance. By microscopically observing the breakage morphology of conductive particles before and after bending, it can be found that bending in the ACF packaging area further exacerbates the previously compressed and broken conductive particles, with cracks continuing to grow and shatter.

Neural correlates involved in perspective-taking in early childhood

Learning to consider another person’s perspective is pivotal in early social development. Still, little is known about the neural underpinnings involved in perspective-taking in early childhood. In this EEG study, we examined 4-year-old children’s brain activity during a live, social interaction that involved perspective-taking. Children were asked to pass one of two toys to another person. To decide which toy to pass, they had to consider either their partner’s perspective (perspective-taking) or visual features unrelated to their partner’s perspective (control). We analyzed power changes in midfrontal and temporal-parietal EEG channels. The results indicated that children showed higher power around 7 Hz at right temporal-parietal channels for perspective-taking compared to control trials. This power difference was positively correlated with children’s perspective-taking performance, specifically for trials in which they needed to pass the toy their partner could not see. A similar power difference at right temporal-parietal channels was seen when comparing perspective-taking trials where children’s visual access mismatched rather than matched that of their partner. No differences were detected for midfrontal channels. In sum, we identified distinct neural activity as 4-year-olds considered another person’s perspective in a live interaction; this activity converges with neural findings of adults’ social processing network.

Multifunctional fluorescence probe for simultaneous detection of viscosity, polarity, and ONOO− and its bioimaging in vitro and vivo

Intracellular microenvironment (viscosity and polarity) and peroxynitrite ions (ONOO−) are involved in maintaining cell morphology, cell function, and signaling so that it is crucial to explore their level changes in vitro and vivo. In this work, we designed and synthesized a mitochondria-targeted fluorescence probe XBL for monitoring the dynamic changes of viscosity, polarity, and ONOO− based on TICT and ICT mechanism. The fluorescence spectra showed obvious changes for polarity at 500 nm as well as ONOO− and viscosity at 660 nm, respectively. The XBL can image simultaneously viscosity, polarity, and ONOO− in cells, and the results showed excess ONOO− leaded to the increase of viscosity in mitochondrial. The ferroptosis process was accompanied by increase of intracellular viscosity and ONOO− levels (or decrease of polarity), which allowed us to better understand the relevant physiological and pathological processes. The XBL can distinguish normal cells and cancerous cells by the fluorescence intensity changes in green and red channels, and image viscosity in inflamed mice. Thus, XBL can provided the chemical tool to understand the physiological and pathological mechanisms of disease by simultaneous detection of viscosity, polarity and ONOO−.

Sensitivity of small river channels in the North Carolina Piedmont to change in streamflow conditions, Atlantic Multi-decadal Oscillation, and land use/land cover change

Twenty-four years (1999–2022) of channel change is assessed using specific-gage analysis based on the United States Geological Survey (USGS) rating curve calibration data from thirteen sites (drainage area < 500 km2) to understand the sensitivity of discharge-specific stage (DSS) or its inverse, stage-specific channel capacity (SSCC) to streamflow regimes, hydroclimatological history, and land use in small Piedmont watersheds of North Carolina, USA. We compare observed channel changes to common streamflow and flood metrics, Atlantic Multi-decadal Oscillation Index (AMOI), and land use/land cover data using regression and correlation techniques to suggest drivers of change and infer sensitivity. In addition to interannual variability, our results at most sites reveal three coherent periods of DSS/SSCC variation at the sub-decadal scale as well as multidecadal trend variation. The magnitudes and frequencies of these changes indicative of potential sensitivity vary substantially amongst sites. The trendlines from the DSS plots for the full length of record indicate that six sites showed increased specific stage while the remaining seven sites showed either reduced or a near-zero change in specific stage. Coefficients of determination relating specific stage and the index of AMO are low (R2 = 0.14—0.38) with both positive and negative relationships exhibited. Multiple regression, coefficients of determination relating specific stage and average monthly discharge are more variable, ranging from 0.18 to 0.94. Both positive and negative correlations (r ≤ 0.7) are found between specific stage and basin land use/land cover intensity indices, although few are significant at 95 % confidence interval. Both qualitative observations and correlation analyses support inferences that drought and persistent low mean discharge conditions tend to increase discharge-specific stage values (decreasing SSCC), by aggradation of the bed and/or lower banks. At our sites, this may be responsible for a sub-decadal trend of increasing specific stage between roughly 2013 and 2018, followed by ongoing reductions over the subsequent period.

Tinnitus-related increases in single-unit activity in awake rat auditory cortex correlate with tinnitus behavior

Tinnitus is known to affect 10–15 % of the population, severely impacting 1–2 % of those afflicted. Canonically, tinnitus is generally a consequence of peripheral auditory damage resulting in maladaptive plastic changes in excitatory/inhibitory homeostasis at multiple levels of the central auditory pathway as well as changes in diverse nonauditory structures. Animal studies of primary auditory cortex (A1) generally find tinnitus-related changes in excitability across A1 layers and differences between inhibitory neuronal subtypes. Changes due to sound-exposure include changes in spontaneous activity, cross-columnar synchrony, bursting and tonotopic organization. Few studies in A1 directly correlate tinnitus-related changes in neural activity to an individual animal's behavioral evidence of tinnitus. The present study used an established condition-suppression sound-exposure model of chronic tinnitus and recorded spontaneous and driven single-unit responses from A1 layers 5 and 6 of awake Long-Evans rats. A1 units recorded from animals with behavioral evidence of tinnitus showed significant increases in spontaneous and sound-evoked activity which directly correlated to the animal's tinnitus score. Significant increases in the number of bursting units, the number of bursts/minute and burst duration were seen for A1 units recorded from animals with behavioral evidence of tinnitus. The present A1 findings support prior unit recording studies in auditory thalamus and recent in vitro findings in this same animal model. The present findings are consistent with sensory cortical studies showing tinnitus- and neuropathic pain-related down-regulation of inhibition and increased excitation based on plastic neurotransmitter and potassium channel changes. Reducing A1 deep-layer tinnitus-related hyperactivity is a potential target for tinnitus pharmacotherapy.

Investigation of Heat Source Layout Optimization by Using Deep Learning Surrogate Models

Abstract The heat source layout optimization (HSLO) is typically used to facilitate superior heat dissipation in thermal management. However, HSLO is characterized by numerous degrees-of-freedom and complex interrelations between components. Conventional optimization methodologies often exhibit limitations such as high computational demands and diminished efficiency, particularly for complex scenarios. This study demonstrates the application of deep learning surrogate models based on the feedforward neural network (FNN) to optimize heat source layouts. These models provide rapid and precise evaluations, with diminished computational loads and enhanced efficiency of HSLO. The proposed approach integrates coarse and fine search modules to traverse the layout space and pinpoint optimal configurations. Parametric examinations are taken to explore the impact of refinement grades and conductive ratios, which dominate the optimization problem. The pattern changes of the conductive channel have been presented. Moreover, the critical conductive ratio has been found, below which the conductive material can no longer contribute to heat dissipation. The outcomes elucidate the fundamental mechanisms of HSLO, providing valuable insights for thermal management strategies.

Structural changes in contagion channels: the impact of COVID-19 on the Italian electricity market

AbstractOperating on electricity markets requires accurately identifying, quantifying, and measuring risk coupled with their corresponding return: this appears as a crucial point, particularly during and after the COVID-19 pandemic. The aim of the present paper is twofold. First, we propose a novel econometric approach to identifying relevant market factors that capture several elements of the risk transmission mechanism inherent in energy systems. The proposed model extends Bayesian graphical models with change points to a multiple-layer set-up. Multilayer graphs encompass the two relevant channels of shock transmission: volatility and price contagion effects. The choice of these two layers seems natural because electricity prices and their spiky nature, coupled with inherent volatility, constitute essential influential elements for market players to maximize their profits. The change-point specification allows for detecting relevant changes in the electricity market. Second, we apply the proposed econometric framework to the Italian zonal markets analyzing the effects of returns and volatility contagion in several periods detected by the model. The last time intervals identified by the change-point methodology overlap the COVID-19 pandemic period. The model captures relevant abrupt changes in prices and volatility in the zonal electricity market and provides new evidence of interconnections in the zones of the Italian market related to the risk alone, price process alone, and risk versus price process relationship and their interactions.

Human interventions alter morphodynamics of meandering channels: Insights from decadal to pre-industrial observations in the Yangtze River

Human activities, such as reservoir construction and bank revetment, significantly alter downstream flow and sediment regimes and river channel changes, impacting river ecosystem services. However, our understanding of how intense human activities affect morphodynamics of meandering channels in big river systems remains incomplete due to the lack of high-resolution in-situ data. Here, we use comprehensive data encompassing hydrology and sediment, historical channel maps, and high-resolution river bathymetry to investigate the evolution of meandering bends in the Middle Yangtze River (MYR) across three distinct phases: the natural period (1490–1975), the bank revetment period (1975–2002), and the post-dam period (2003–2018). The study revealed that, in the absence of human intervention, the meandering channels of the MYR naturally experienced inner bank deposition and outer bank erosion, largely governed by curvature-induced secondary flow patterns in flow and sediment transport mode. In 1975–2002, outer-bank revetments reduced erodibility, stabilizing outer banks, while inner banks continued to experience lateral and vertical deposition, causing a narrower and deeper channel hydraulic geometry. Conversely, meandering bends had exhibited an unusual pattern of ‘outer bank deposition and inner bank erosion’ in 2003–2018. Channel morphological changes characterized by channel incision and widening were driven by changes from erodible bank boundaries to solidified bank boundaries, substantial reduction in suspended sediment concentration, and an altered and extended effective flow range (10,000–25,000 m3/s). Our findings highlight that human interventions such as damming and bank revetments can alter the conventional erosion–deposition morphodynamics of meandering bends in large river systems, carrying vital implications for sustainable river management in the Anthropocene.

Multi‐decadal quantification of interactions between coarse sediment fluxes and channel management in South Tyrol, Eastern European Alps

AbstractChannel incision and narrowing have occurred in the 20th century in most Alpine rivers. However, the causal links between sediment‐related human engineering and exploitation and morphological changes in rivers are mostly unclear. This study presents an analysis of the evolutionary trajectories of the main active channels in the upper Etsch/Adige River basin (Eastern European Alps) coupled with their modifications in terms of coarse sediment transport. Channel planform variations were quantified in 15 rivers (total length of 630 km) using multi‐temporal analysis of historical maps and orthophotos. Sediment volumes excavated from river channels or trapped by hydraulic structures (dams and retention basins) were retrieved from historical records, along with geospatial information regarding the presence of lateral and longitudinal consolidation works and land use variations. Results indicate that most rivers underwent slight narrowing and some of them experienced widening, from the mid‐19th century to the 1950s. From the 1950s to the late 1990s, severe variations in terms of narrowing and morphological simplification took place in all rivers. The analysis of channel changes in relation to human activities shows that gravel mining carried out in the period 1970s–1990s appears to have been the main cause of sediment imbalance in the rivers which narrowed the most. Since the 2000s, when gravel mining was banned by law, channel adjustments have become negligible throughout study area. Nevertheless, the trapping of a large share of coarse sediment fluxes—at the river basin scale—by retention check dams and hydropower dams has impeded rivers from recovering to their original conditions.

Numerical investigation of supercritical flow and heat transfer mechanism in printed circuit heat exchanger (PCHE) channels

A numerical study is conducted to investigate supercritical hydrogen flow and heat transfer mechanisms and characteristics in printed circuit heat exchanger (PCHE) channels. The impact of large variations of the thermal-physical properties due to a wide range of operating temperatures have been studied and analyzed in detail. The heat transfer mechanisms of supercritical hydrgen under horizontal and vertical flow conditions are studied numerically. In addition, the influence of different cross-section shapes of the channel is also analyzed. The results show that asymmetrical fluid temperature distributions near the top wall and bottom wall due to the buoyancy effect result in heat transfer deterioration. Spiral flow occurs in the heat transfer deterioration region, which further confirms that the heat transfer deterioration is related to the spiral flow effect caused by the buoyancy effect. The heat transfer coefficient without gravity is lower than that with gravity, indicating that the buoyancy effect enhances the overall heat transfer in the horizontal circular channel. Furthermore, the fluid temperature in the vertical upflow channel decreases slowly from the near wall to the core area, while the fluid temperature in the vertical downflow channel changes sharply, which directly leads to the difference in the temperature gradient near the wall. Compared with the square cross-section channel and semicircular cross-section channel, the supercritical hydrogen can achieve greater heat transfer performance in the circular cross-section channel.

Artistic creativity, digital technologies and theatrical sustainability: Integrating new media in theatre practice

Arts and technology have continually been inter-related. Artistic expressions have been facilitated by technological innovations that enable artists either to adapt technologies meant for other purposes, or to invent them as a way to foster the creative process. The evolution of digital technologies in the knowledge era has had a huge impact on the theatre profession, in which digital transformation has influenced the ways theatrical contents are created, presented, distributed and circulated to audiences. This article examines technological advances of the digital era and their impact on the performing arts/the theatre. Relying on the Technology Acceptance Model (TAM), this study argues that new technologies and media enable the creation of new forms of arts that stimulate radical changes in the distribution channels of cultural and creative products (CCPs) based on their digitalisation and dematerialisation. The study finds that digitalisation provides creative artists with new tools and means of artistic expression. Indeed, digitalisation enhances and inspires not only the creation of new art forms but also the presentation of traditional arts by enabling multimedia experiences and interactivity. The paper recommends that, given the reality of globalisation and its concomitant emergence of virtual communities, theatrical performances must adopt new media tools in terms of content creation, exhibition and distribution, to remain functional.

Assessing Riverbank Change Caused by Sand Mining and Waste Disposal Using Web-Based Volunteered Geographic Information

River water is one of the most important natural resources for economic development and environmental sustainability. However, river water systems are vulnerable in some of the densely populated regions across the globe. Intense sand mining and waste disposal can lead to river changes, loose foundations, and biodiversity loss. This study aims to develop a web-based geographic information system (GIS) platform to monitor river channel changes and their impacts on river environments due to sand mining and waste burial. The system integrates open-source software, Windows Server 2012, a web server, and PostgreSQL with PostGIS plugins for efficient mapping and storage of geospatial data and volunteered reporting of location events. Interferometric methods, including SNAP2STAMPS Automated Algorithm, persistent scatterer interferometry (PSI), small baseline subset (SBAS), and Snap software, were used to analyze spatial changes of subsidence from Sentinel-1 satellite data from 2021 to 2023 in the Gadar River in Oshnavieh, Iran. The results showed that the maximum subsidence at the riverbank was −10.1 cm due to sand mining, and the maximum uplift was 8.2 cm due to waste landfilling. The average subsidence was reported to be −5.1 cm. The results emphasize spatial analysis, showcasing material mining’s impact on subsidence trends and underscoring the significance of public participation in monitoring river health. Three parameters—completeness, correctness, and quality—were used to validate the system. Validation results showed completeness, correctness, and quality rates of 94.15%, 92.48%, and 86.63%, respectively.

Channel morphological change monitoring using high-resolution LiDAR-derived DEM and multi-temporal imageries

Natural processes and human activities both cause morphological changes in channels. Remote sensing products are often used to assess planform changes, but they tend to overlook vertical changes. However, considering both planform and vertical changes is crucial for a comprehensive evaluation of morphological changes. Using spatiotemporal aerial imagery and topographic data, remote sensing plays a vital role in evaluating channel morphological changes and flood-carrying capacity. This study aimed to investigate the morphological changes of a creek in an urban catchment using very high-resolution remote sensing products. In this study, we developed a new framework for investigating overall channel morphology change by employing very high-resolution aerial imagery and a LiDAR-derived digital elevation model (DEM). By digitizing channel boundaries using ArcGIS Pro 3.0, and analyzing various morphological parameters, erosion, and deposition patterns, we examined the impact of urban expansion and infrastructure development on channel adjustments. Channel adjustments have been performed in the case study catchment (Dry Creek, South Australia, Australia) due to urban expansion and development of infrastructure in the downstream reaches. Our findings revealed a significant southwest shift in the planform of the channel, with a maximum shift of 478 m and an average shift of 217 m since 1998. This alteration resulted in an increase in the sinuosity index reaching 1.2. Over the period from 2018 to 2022, the channel experienced a net deposition depth of 3.4 cm to 3.6 cm in downstream reaches. The annual deposition volume in the downstream reaches was 1963 m3, necessitating regular desilting to prevent channel capacity loss and flooding in the surrounding environment. This study also highlights the incremental growth of riparian vegetation within the channel, which affects surface roughness, channel slope, and carrying capacity. These findings provide a valuable baseline for future investigations into stream channel morphology changes and emphasize the importance of implementing appropriate measures such as desilting and vegetation management to mitigate deposition levels, reduce flood risks, and enhance the overall health and functionality of Dry Creek. The framework used in this study can be applied to other case studies employing reliable and high-resolution remote sensing data products.

A Case Study on Business Continuity following the Establishment of a Soho Fashion Shopping Mall: Longitudinal Research

This study analyzed the current operational status, business continuity, and business continuity strategies of 11 Soho fashion shopping malls through a longitudinal case study (2019/2020 and 2022/2023). The aim was to determine how Soho fashion shopping malls are continuing their business having been successfully established in the fiercely competitive current online fashion market. Regarding changes in shopping mall operation status, all cases displayed changes in items, distribution channels, marketing channels, core values, and profit structures. After establishing the businesses, a crisis arose due to the COVID-19 pandemic, leading to difficulties in creating new customers. Moreover, there was excessive business expansion, resulting in saturation of the online platform store market. This meant companies were experiencing reduced sales (5) or difficulties in maintaining their business (3). However, there were differences in the direction of overcoming the crisis and continuing or converting the business. These revealed that to continue the business after successful establishment of an online fashion shopping mall, it is essential to have the expertise of entrepreneurs, work performance, and marketing ability, as well as differentiation capabilities such as product power and management strategy and core competitiveness that provides a relative advantage over other shopping malls. Customized government support at the level of the start-up ecosystem is also essential for the survival and business continuity of a SOHO online fashion shopping mall with poor human and material resources.