Site Characteristics Research Articles

Revisiting moated sites in Northeast Thailand: integrating spatial analysis with previous and new research insights

Moated sites in northeast Thailand serve as pivotal evidence of human–environment interaction since the Iron Age and have been subject to extensive study. This research conducts a comprehensive examination of moated sites, aiming to analyze their spatial characteristics and relationships with physical environmental factors across various scales, including regional and major river basins. To achieve these goals, advanced GIS tools including average nearest neighbor (ANN) analysis, kernel density estimation (KDE), standard deviational ellipse (SDE) analysis, and the Kruskal–Wallis test are employed. By incorporating a dataset of 468 moated sites and expanding the geographic scope beyond previous studies, this research offers new insights into settlement patterns and environmental interactions. Contrary to earlier interpretations suggesting random dispersion, the study’s findings reveal a clustering pattern, indicating intentional spatial organization by ancient communities. The study also highlights the influence of rainfall on the number of moats, with multiple moats more common in lower rainfall areas and single moats in higher rainfall regions. Additionally, the results observe that sites with more moats are typically found at higher elevations, although no significant correlation between elevation and site size was identified, challenging previous studies' conclusions. These results underscore the importance of local environmental conditions, such as rainfall and elevation, in shaping the distribution and characteristics of moated sites. The findings highlight the complex interplay between environmental factors and human settlement strategies, emphasizing the role of water management in ancient communities.

Dermatoscopic features of vulvar lichen sclerosus in children: A retrospective study.

To explore the dermoscopic features of lichen sclerosus in different parts of the external genitalia in children. A retrospective analysis of the dermoscopic features of 42 female children with vulvar lichen sclerosus treated in the Department of Dermatology of Shanxi Children's Hospital from January 2020 to May 2023. Among the 42 female children, aged 3-14 years (mean: 7.24 ± 2.43 years), the duration of vulvar lichen sclerosus ranged from 3 months to 2 years (mean: 9.83 ± 4.93 months). Clinical lesions occurred in the labia minora in 18 cases (42.9%), labia majora in 38 cases (90.5%), posterior fourchette in 36 cases (85.7%), perianal area in 13 cases (31.0%), anterior fourchette in 17 cases (40.5%), clitoris in seven cases (16.7%), and interlabial sulcus in 11 cases (26.2%). Dermoscopic findings common in the labia majora included follicular keratotic plugs, cloverleaf-like structures, comedo-like openings, and linear vessels (p < .05); however, purple-red globules and patches and white linear streaks were more common in the posterior fourchette (p < .05), whereas dotted vessels were more common in the labia minora (p < .05). Common dermoscopic findings in pediatric vulvar lichen sclerosus were yellow-white structureless areas, white linear streaks, follicular keratotic plugs, and cloverleaf-like structures; yellow-white structureless areas and white linear streaks showed the highest specificity. The dermoscopic findings varied among different affected areas, which provides a basis for further understanding of the characteristics of different sites of vulvar lichen sclerosus in the pediatric population.

Site selection of floating photovoltaic systems on hydropower reservoirs using fuzzy sine trigonometric decision-making model: Turkey as a case study

Floating photovoltaic systems are a promising option for renewable energy by mitigating the drawbacks of land-based photovoltaic systems. However, renewable energy systems are designed in a site-specific way, therefore, the performance of renewable energy alternatives substantially depends on the selected site characteristics. In this study, a comprehensive assessment was performed to identify the optimal hydroelectric power plant reservoir for floating photovoltaic system deployment in Turkey using the Geographical Information System and Multi-Criteria Decision Making method. A two-staged methodology was used to evaluate the results of questionnaires including several expert opinions. In the first stage, a nonlinear fuzzy Aczel-Alsina functions based Ordinal Priority Approach method was employed to weigh the fourteen sub-criteria based on technical, environmental, economic and social considerations. In the second stage, fuzzy sine Trigonometric based Additive Ratio Assessment method was used to rank the fifteen hydroelectric power plant reservoirs all across Turkey. Despite the global horizontal irradiation being the most important criterion, Sarıyar hydroelectric power plant reservoir, with one of the lowest global horizontal irradiation values among alternatives, was determined as the most suitable dam reservoir for floating photovoltaic installation in Turkey. Therefore, the findings of this study highlight the importance of comprehensive analysis that considers the several assessment criteria from fundamental aspects to achieve reliable site selection for floating photovoltaic systems.

Land Evaluation of Tribal Talukas of Bharuch District in South Gujarat, India

Climate change interrupts existing agriculture, emphasizing the need for land evaluation to assess current capacities and introduce climate-resilient alternative crops. A study was undertaken to evaluate soils of three tribal talukas viz. Jhagadia, Netrang and Valia of Bharuch district in South Gujarat during 2021-24. The total fifteen representative soil profiles were identified and excavated from various landforms based on GIS maps. Land evaluation was conducted using land capability classification, land irrigability classification and soil site suitability for existing crops and alternative crops for the study area. The study area is predominantly classified under Land Capability Class II, indicating minor limitations and covering the majority of the region. The study area also includes Class III with moderate limitations and Class IV in Netrang taluka, which faces severe limitations due to soil quality, wetness, and erosion. The study area soils were grouped under three irrigability classes with further divided into six sub-classes based on the limitation of soils and site characteristics. Soil suitability indicates high cotton potential in specific profiles, while pigeonpea and soybean shows broad suitability. Sugarcane thrives in Jhagadia and Valia, with marginal suitability in Netrang and banana is highly suitable in most of Jhagadia. Key alternative crops suitable for the study area are finger millet, castor, groundnut, green gram, cluster bean, mango, guava and Kamalam. The study advocates soil and water conservation for intensified, sustainable agriculture, proposing tree-based BAIF's Wadi model for hilly terrains.

Risk Factors for Secondary-Inserted Orthodontic Miniscrew Stability Following Original Insertion Failure.

The objective of this study was to examine the variables that influence the stability of secondary orthodontic anchoring miniscrews after the occurrence of initial installation failure. The secondary insertion was defined as reinserted, which was inserted to the orthotopic (i.e., inserted between the roots of the original two adjacent teeth with the mesiodistal, height and insertion angle slightly altered) and ectopic (i.e., inserted between neighboring tooth roots). A total of 100 miniscrews were reinserted in 71 patients who experienced primary insertion failure. The analysis considered 15 independent variables related to systemic factors and site characteristics. The success rate and risk factors associated with reinsertion were assessed using univariate analysis (Chi-square Test for categorical variables and Mann-Whitney U test for continuous variables) and correlation analysis (Spearman correlation analysis to exclude variables that might cause interference in a multivariable model). Significant parameters from univariate analysis were then integrated into a generalized estimating equation (GEE) model. The success rate of reinsertion was 66.00% (66/100), and the cancellous bone density and the patient's age had a strong correlation with the stability of reinserted miniscrews. The study indicates that younger patients with miniscrews reinserted in areas of high cancellous bone density are more likely to experience instability. This finding warrants careful consideration by orthodontists when performing miniscrew reinsertion procedures.

Refining Sampling Efforts for Fish Diversity Assessment in Subtropical Urban Estuarine and Oceanic Waters Using Environmental DNA With Multiple Primers

ABSTRACTThe environmental DNA (eDNA) approach is an emerging tool for monitoring marine biodiversity. However, the sampling effort needs optimization according to the site characteristics and target taxonomic groups. In this study, we optimized the eDNA sampling effort in terms of sample volume and number of replicates to monitor the diversity of marine vertebrates (mainly fish) in Hong Kong's subtropical waters that show a gradient of estuarine to oceanic waters. To maximize detection, we used three pairs of metabarcoding primers (12S‐v5, MiFish‐U, and MiFish‐E). We compared vertebrate diversity in 78 water samples, ranging from 1 to 10 L, collected from oceanic and estuarine sites. Metabarcoding yielded a total of 140 vertebrate species, of which 18 were unique to the estuarine site, 66 unique to the oceanic site, and 56 shared between both sites. The detected species were predominantly ray‐finned fish (136 species), and the three primer pairs exhibited differential sensitivity toward different taxa, especially cartilaginous fish and cetaceans. Increasing sampling volume per replicate generally increased the total detected species, average species per replicate, and species coverage, and sampling 3 or 4 × 4 L represented the most efficient sampling effort for the estuarine and oceanic sites, respectively. The diversity analysis revealed that sampling &gt;2 L per replicate reduced variability and improved diversity analysis. The results also showed that a larger sampling volume per replicate increased the probability of detecting endangered, indicator, invasive, and elusive species, with 4 L representing the most efficient volume. This study recommended sampling 4 L per replicate and 3 replicates for estuarine and 4 for oceanic sites, respectively for effectively monitoring marine fish in subtropical waters using the eDNA approach.

Landscape structure and site characteristics influence whether the northern house martin Delichon urbicum occupies artificial nests.

Artificial nest sites can support populations of endangered species when they are correctly installed. Here we analysed the characteristics and conditions that determined whether the northern house martin Delichon urbicum occupied more than 300 artificial nests around the city of Münster, Germany. We found that artificial nest occupation rates were influenced by various environmental and temporal factors. Positive influences included a longer time since installation and, to a lesser extent, the number of artificial nests at the same site. Negative impacts were observed from higher proportions of sealed surface cover in the surrounding area and, to a lesser extent, southward exposure. The distance to the nearest water body and the number of occupied natural nests showed no significant effect. We compared our results with descriptive evidence from the grey literature and published reports, and we give recommendations for installing artificial house martin nests for conservation practitioners. Future studies should also investigate the potential negative effects of 'dirt boards' below the nests and of gaps between the roof and the artificial nests.

Mixed stands of black spruce (Picea mariana) and tamarack (Larix laricina) offer high secondary growth in eastern boreal forests of Canada

The Canadian boreal forest is still lacking investigation into compatible species mixtures that can lead to higher growth rates than monospecific or pure stands. The effect of species mixtures on stand productivity can vary with stem density, species proportion, site characteristics, and climate variation. We investigated mixed stands of black spruce (Picea mariana) and tamarack (Larix laricina) in eastern Canadian boreal forests. Using modern forest survey data, we analyzed stand basal area variation in 756 mature stands exclusively composed of these two species over a study area spanning 535,000 km². We generated a linear relationship between mixed stand basal area and stem density, and the residual of this relation was used as response variable named ‘residual basal area’. Positive and negative deviations of residual basal area were analysed with generalized additive models and quantile regressions with tamarack basal area, climate, and site characteristics as explanatory variables. The selected model included tamarack basal area, mean seasonal precipitation, degree days, mean annual temperature, stand age, latitude, longitude, and the type of surficial deposit. Tamarack exhibited a linear positive effect on predicted residual basal area. The most significant effect was observed from the interaction between tamarack basal area and stand age, predicting positive residual basal area of 16 m² ha−1 when stand aged was 150 years old and tamarack basal area was between 12 and 17 m² ha−1. Quantile regressions revealed that tamarack could enhance basal area while increasing black spruce stem size and density. Landscape managers may consider the establishment of mixed black spruce and tamarack stands to favor secondary growth in eastern Canadian boreal forests.

Tuning the morphology and textural properties of ZSM-5 additive for co-cracking of waste plastics with vacuum gas oil to light olefins

Typical cracking catalysts, called equilibrium catalyst (E-Cat) are ultra-stable Y (USY) zeolite often used with 15% commercial ZSM-5 zeolite additive (ZSM-5(COM)) to boost olefin yield. In this study, similar additive zeolites with different pore sizes and acidic character were synthesized by rapid ageing of precursor solution and used in the co-cracking of low-density polyethylene (LDPE) and heavy vacuum gas oil (HVGO). Three ZSM-5 zeolites additives with Si/Al ratio 25 (ZSM-5(25)), 50 (ZSM-5(50)) and 75 (ZSM-5(75)) were synthesized and combined with E-Cat to form E-Cat/ZSM-5(25), E-Cat/ZSM-5(50) and E-Cat/ZSM-5(75) respectively. The E-Cat/ZSM-5(50) has slightly better endothermic conversion (cracking) of a mixture of dissolved LDPE and HVGO into H2, C1 to C4 gases and C2-C4 light olefins (total conversion of E-Cat 80.0%, E-Cat/ZSM-5(COM) 75.0% and E-Cat/ZSM-5(50) 83.7% respectively), with different gas, liquid and coke distributions. The E-Cat/ZSM-5(75) has 81% conversion, and highest yield of light olefins (38.4%). Structural (surface area, pore size) and chemical (acid sites) characteristics of the synthetized ZSM-5(75) zeolite explain the observed higher light olefin selectivity by different and competing catalytic routes. The ZSM-5(75) has demonstrated to be a good zeolite additive for converting dissolved plastic in HVGO into light olefins.

The Bio-Restorative Concept for Implant-Supported Restorations.

This study aims to present the bio-restorative approach in implant dentistry, which combines biological and restorative concepts through digital planning. This concept combines periodontal, surgical, and prosthetic variables, aiming to reduce patient morbidity while achieving satisfactory esthetic and functional outcomes in implant-supported restorations in the long term. Implant dentistry evolved from a primarily surgical to a recent prosthetically driven approach. This evolution was partly due to advancements in bone reconstructive techniques and an increased demand for esthetic outcomes. Recently, digital planning has introduced a new paradigm that allows for the full integration of both approaches. The bio-restorative concept considers functional, esthetic, and biological variables in a virtual planning environment. This is achieved through the simultaneous digital assessment of (A) anatomical site characteristics and (B) implant restorative variables. These variables include digital tooth arrangement, soft-hard tissue conditions, implant variables, supra-platform components, and a surgical plan that respects or modifies peri-implant phenotype. The bio-restorative concept is intended to improve contemporary implant dentistry by integrating updated biological and prosthetic notions through digital planning. Adopting this paradigm has the potential to redefine the standards in implant dentistry, fostering a holistic and patient-centered approach. It enhances patient and clinician satisfaction through more efficient and less invasive procedures. Significantly, it improves predictability, leading to successful implant-supported restorations in the long term.

Polarimetric characterization of Chandrayaan-3 landing site near lunar south pole using high resolution Chandrayaan-2 DFSAR data

The Chandrayaan-3 (CH3) Vikram lander presents an unique opportunity to study the radar scattering behavior of the landing site as well as human-made dihedral structure on the lunar surface. This opportunity is made possible by the Dual-Frequency Synthetic Aperture Radar (DFSAR) sensor onboard the Chandrayaan-2 orbiter, which has the highest resolution and polarimetric capabilities compared to any planetary SAR sensor. To explore this, we utilized DFSAR to capture high-resolution images of the CH3 landing site during pre-landing and post-landing condition, with a pixel spacing as fine as 1 m, in a hybrid-pol mode. The landing site exhibits dominant volume and even-bounce radar scattering behavior similar to an ideal dihedral geometry. Furthermore, we observed an exceptionally high Circular Polarization Ratio value at the landing site (1.99 ± 0.30), a rarity among natural features on the lunar surface. Besides, the landing site is characterized by enhanced average dielectric constant value (5.76 ± 3.11). The post-landing DFSAR image reveals a 177 m2 area, surrounding the CH3 landing location, characterized by high CPR and elevated even bounce and volume scattering. The drastic enhancement of the average CPR value (7-times), dielectric value (2-times), even bounce and volume scattering in the landing site, in comparison with the pre-landing DFSAR observation, is due to presence of lander module and disturbance in the regolith structure in the landing area. The polarimetric characteristics of the landing site distinguish it from the major natural features on the lunar surface, such as regolith, debris flow, and impact ejecta. This investigation is of utmost importance as it emphasizes the effectiveness of high-resolution DFSAR acquisitions for evaluating the polarimetric behavior of small-scale features, which can be invaluable for characterizing landing sites in upcoming missions.

Physiological trait coordination and variability across and within three Pinus species.

Studies have explored how traits separate plants ecologically and the trade-offs that underpin this separation. However, uncertainty remains as to the taxonomic scale at which traits can predictably separate species. We studied how physiological traits separated three Pinus (Pinus banksiana, Pinus resinosa, and Pinus strobus) species across three sites. We collected traits from four common leaf and branch measurements (light-response curves, CO2-response curves, pressure-volume curves, and hydraulic vulnerability curves) across each species and site. While common, these measurements are not typically measured together due to logistical constraints. Few traits varied across species and sites as expected given the ecological preferences of the species and environmental site characteristics. Some trait trade-offs present at broad taxonomic scales were observed across the three species, but most were absent within species. Certain trade-offs contrasted expectations observed at broader scales but followed expectations given the species' ecological preferences. We emphasize the need to both clarify why certain traits are being studied, as variation in unexpected but ecologically meaningful ways often occurs and certain traits might not vary substantially within a given lineage (e.g. hydraulic vulnerability in Pinus), highlighting the role a trait selection in trait ecology.

Theory and analytical solutions to wellbore problems with hardening/softening Drucker-Prager models

Recognizing and quantifying the elasto-plastic nature of underground formations is critical for various subsurface operations such as drilling, stimulation, production, injection, and storage. In the case of geological CO2 storage, for instance, it is key to identify storage sites characteristics and pumping parameters that lead to safe and perennial CO2 trapping. In this work, we investigate different rock hardening/softening behaviors with the Drucker-Prager model: cohesion hardening/softening, friction hardening/softening, and their combination, jointed hardening/softening. Our focus is to solve the elasto-plastic deformation analytically in the vicinity of a wellbore. The three hardening/softening formulations predict different mechanical responses and stress-paths for solving the same wellbore problem with excavation. The analytical solutions for 2D axisymmetric problems with different hardening laws are provided in this study and verified with corresponding numerical results. This approach can be used to interpret field observations and calibrate experimental data with more comprehensive models. These new laws are implemented and benchmarked in GEOS, an open-source advanced numerical simulator of subsurface formations. This study enhances our understanding of subsurface rock's elasto-plastic behavior and offer analytical references for interpretating experimental measurements and developing numerical simulations for solving wellbore problems.

Post-depositional modification on seasonal-to-interannual timescales alters the deuterium-excess signals in summer snow layers in Greenland

Abstract. We document the isotopic evolution of near-surface snow at the East Greenland Ice Core Project (EastGRIP) ice core site in northeast Greenland using a time-resolved array of 1 m deep isotope (δ18O, δD) profiles. The snow profiles were taken from May–August during the 2017–2019 summer seasons. An age–depth model was developed and applied to each profile, mitigating the impacts of stratigraphic noise on isotope signals. Significant changes in deuterium excess (d) are observed in surface snow and near-surface snow as the snow ages. Decreases in d of up to 5 ‰ occur during summer seasons after deposition during two of the three summer seasons observed. The d always experiences a 3 ‰–5 ‰ increase after aging 1 year in the snow due to a broadening of the autumn d maximum. Models of idealized scenarios coupled with prior work indicate that the summertime post-depositional changes in d (Δd) can be explained by a combination of surface sublimation, forced ventilation of the near-surface snow down to 20–30 cm, and isotope-gradient-driven diffusion throughout the column. The interannual Δd is also partly explained with isotope-gradient-driven diffusion, but other mechanisms are at work that leave a bias in the d record. Thus, d does not just carry information about source-region conditions and transport history as is commonly assumed, but also integrates local conditions into summer snow layers as the snow ages through metamorphic processes. Finally, we observe a dramatic increase in the seasonal isotope-to-temperature sensitivity, which can be explained solely by isotope-gradient-driven diffusion. Our results are dependent on the site characteristics (e.g., wind, temperature, accumulation rate, snow properties) but indicate that more process-based research is necessary to understand water isotopes as climate proxies. Recommendations for monitoring and physical modeling are given, with special attention to the d parameter.

Aquatic invasive species exhibit contrasting seasonal detectability patterns based on environmental DNA: Implications for monitoring

Abstract Aquatic invasive species (AIS) are a global threat to freshwater biodiversity and ecosystem services. Documenting AIS prevalence at broad spatial scales is critical to effective management and early detection. However, conventional monitoring for AIS is costly and is rarely applied at the resolution and scale required for effective management. Monitoring of AIS using environmental DNA (eDNA) has the potential to enable broadscale surveillance at a fraction of the cost of conventional methods, but key questions must first be addressed related to how eDNA detection probability varies among environments, seasons, and multiple species with different life histories. To quantify spatiotemporal variation in the detection probability of AIS using eDNA sampling, we surveyed 20 lakes with known populations of four aquatic invasive species: common carp (Cyprinus carpio), rusty crayfish (Faxonius rusticus), spiny waterflea (Bythotrephes longimanus), and zebra mussels (Dreissena polymorpha). We collected water samples at 10 locations per lake, five times throughout the open water season resulting in a total of 1,000 water samples. Quantitative polymerase chain reaction was used with species‐specific assays to determine the presence of each species' eDNA in water samples. With Bayesian occupancy models, we quantified the effects of lake and site characteristics and Julian date on eDNA detection probability. The probability of eDNA detection varied seasonally, and the seasonal variation was species‐specific and related to species life histories. Zebra mussel eDNA was generally the most detectable among the species we targeted, and detection probability peaked in midsummer when only six water samples were required to achieve a 95% probability of detection (80% Bayesian credible interval: 3–12 samples). Spiny waterflea eDNA detections also peaked in mid to late summer, but were overall the most difficult species to detect, requiring 160 samples for a 95% probability of detection (80% Bayesian credible interval: 67–1,616 samples). Common carp eDNA was most detectable in the spring and rusty crayfish eDNA was most detectable in the early autumn, corresponding to key life history events. Sampling for eDNA during the optimal time of the year for each species decreased the number of samples required to reach a 95% probability of detection by an order of magnitude or more. Our results are relevant for decision makers interested in using eDNA as a multi‐species monitoring tool and highlight the importance of life history in the efficacy of eDNA monitoring.

Combined Effects of Local and Regional Drivers on Oyster Spat Density and Growth in Eastern Australia

Up to 85% of shellfish reefs have been lost worldwide, resulting in declining ecosystem services, and increasing restoration demand. However, more information regarding the conditions which maximise oyster settlement and growth is required to optimise restoration. We deployed oyster settlement tiles at 21 intertidal sites throughout Moreton Bay, Australia; a region where > 96% of rock oyster reefs are lost and demand for restoration is high. We quantified effects of variables describing the spatial (from GIS), local habitat (using quadrats and water quality measures), and oyster predator (using underwater videography) characteristics of sites on oyster density and size on tiles. Oyster density was highest at sites with intermediate predator abundance and temperature, highest nearby invertebrate cover, and low and high values of turbidity and nearby rock and algae cover. Conversely, oyster size was highest at sites with intermediate predator density, higher fish species richness and turbidity, and lowest temperatures. Together, this showed that optimal restoration requires sites with 22 to 23 °C average water temperatures, between 10 and 15 oyster predators, and either low (< 2 NTU) or high (> 6 NTU) turbidity levels. Notably, we observed multiple peaks for several variables, suggesting the potential presence of multiple cryptic oyster species on settlement tiles. We found that oysters shared preferred environmental conditions with polychaetes, coralline algae, and tunicates, and were more prevalent and abundant at sites with lower turf algae, barnacle, and mussel cover. Identifying environmental variables influencing oyster population distribution, settlement, and growth can guide the selection and approach of oyster restoration sites.

Exploring the catalytic characteristics of binuclear bimetallic FeM sites (M = Co, Ni, Pt) on nitrogen-doped graphene through density functional theory and ab initio molecular dynamics

Certain supported bimetallic catalysts exhibit high efficiency in both oxygen reduction reactions (ORR) and oxygen evolution reactions (OER). However, the catalytic mechanism of double-atom catalysts and how different-atom active sites affect charge transfer efficiency have not been fully revealed. In this work, we provide density functional theory (DFT) simulations of ORR/OER on FeM-NC (M = Co, Ni, Pt) supported on nitrogen-doped graphene. The stability of structures, electrical properties, adsorption energies of intermediates, and catalytic activity of ORR/OER on FeM-NC have been investigated. The results indicate that the Fe-atom in stable FeM-NC structures is a catalytically active site and that the FeM-NC-1 structures may be more appropriate as catalysts. The overpotentials for ORR/OER on FeM-NC-1 (M = Co, Ni, Pt) are 0.42/0.29 V on FeCo-NC-1, 0.57/0.33 V on FeNi-NC-1, and 0.64/0.33 V on FePt-NC-1, which is significantly lower than those on Pt(111) surfaces. Ab initio molecular dynamics (AIMD) simulations suggest that ORR/OER may occur vis a typical four-electron mechanism on FeNi-NC-1 and FePt-NC-1 configurations, while on FeCo-NC-1 structures, it may involve two different four-electron pathways. This study increases our knowledge of the structural stability of FeM-NC-1 structures as bifunctional catalysts and the ORR/OER pathway in acidic solution, and it also shows that three FeM-NC-1 structures are suitable candidate catalysts for ORR/OER.

Seismic response characteristics of offshore sites in the Sagami Bay, Japan—Part I: Comparison of spectral inversion and ratio under weak motions

Understanding offshore site amplification (AF) characteristics is crucial for marine engineering. Thus far, the spectral ratio (SR) has been widely used to analyze offshore AF characteristics, despite its reliability not yet being fully investigated. In this study, we used 826 ground-motion data recorded at 6 offshore and 19 onshore stations in the Sagami Bay region to reveal the source, path, and AF characteristics using the generalized inversion technique (GIT). The average stress drops for the shallow crustal, subduction interface, and subduction slab earthquakes were 3.55, 6.59, and 7.07 MPa, respectively. The offshore sites were categorized into flat and steep stations based on the local slope gradient (LSG), and systematic AF characteristics were observed. We found that the topography had a negligible influence on the flat free-field station KNG205. AFs obtained using the GIT and SR were analyzed and compared, revealing two main differences: (1) SR-obtained AF values were significantly larger than GIT-obtained AF values above 0.5 Hz and 5 Hz at the flat and steep sites, respectively; (2) resonant frequencies estimated using the SR drifted to lower and higher frequencies for flat and steep sites, respectively. The ineffectiveness of the SR for flat and steep stations was attributed to the effects of topography and seawater pressure on low- and high-frequency vertical ground-motions, respectively. These results suggest that the SR is only reliable for estimating AF curves at marine free-field sites and low-frequency AFs at steep sites. The LSG may play an important role in offshore ground-motion studies.

Site characteristics determine the prevalence of extreme weather events affecting freshwater macroinvertebrate communities

Understanding the impacts of extreme weather events on freshwater ecosystems is imperative during a time when a multitude of challenges compromises these environments' health. Exploring how such events affect macroinvertebrate communities in rivers sheds light on the resilience of freshwater ecosystems, which is essential for human well-being and biodiversity conservation. In this study, long-term time series of benthic macroinvertebrate communities from four sites along three freshwater streams within the Rhine-Main-Observatory Long-Term Ecological Research site in Germany were analyzed. Each of them was sampled annually over a span of ~20 years to assess the impacts of extreme weather events (floods, droughts, and extreme heat) on macroinvertebrate communities. The findings reveal that the effects of extreme events are site-specific, suggesting that the impacts of an extreme event can vary based on several potential factors, including the life history traits of the organisms within the community and, among others, the hydrography of the site. Moreover, the analysis highlights that the cumulative impact of these events over time is more significant than the impact of a single event's magnitude, while following distinct temporal dynamics. This underscores the importance of considering both the temporal dynamics and the biological characteristics of communities when evaluating the consequences of extreme weather events on biodiversity, illustrating that the resilience of freshwater ecosystems and their biodiversity under such conditions depends on a complex interplay of factors rather than the severity of individual events.

Risk factors for pathological upgrading and noncurative resection in patients with gastric mucosal lesions after endoscopic submucosal dissection

BackgroundThe pathological results obtained from endoscopic forceps biopsy (EFB) do not always align with the findings of postoperative endoscopic submucosal dissection (ESD). Furthermore, as ESD becomes more widespread, the number of noncurative endoscopic cases increases; thus, an accurate preoperative diagnosis and an appropriate treatment method are crucial. The purpose of this study was to explore the risk factors for postoperative pathological upgrading and noncurative resection and to gather experience in clinical and pathological diagnosis.MethodsFrom March 2016 to November 2023, 292 ESD specimens were collected from 262 patients with gastric mucosal lesions. Clinicopathological information, the coincidence rate of pathological diagnosis between EFB and ESD specimens, and risk factors related to noncurative resection were analyzed retrospectively.ResultsThe overall upgraded pathological diagnosis rate between EFB and ESD was 26.4%. The independent predictors for the upgraded group included proximal stomach lesions, lesion size > 2 cm, surface ulceration, and surface nodules. Twenty of the 235 early gastric cancer (EGC) patients underwent noncurative ESD resection. Multivariate analysis showed that undifferentiated carcinoma and tumor infiltration into the submucosa were significantly associated with noncurative resection.ConclusionBiopsy cannot fully represent the lesions of gastric intraepithelial neoplasia (GIN). When a suspected epithelial dysplasia is suspected, a careful endoscopic examination should be conducted to evaluate the lesion site, size, and surface characteristics to ensure an accurate diagnosis. Noncurative endoscopic resection is associated with undifferentiated carcinoma and submucosal infiltration. Clinicians must be familiar with these predictive factors for noncurative resection and select the appropriate treatment for their patients.