Edge Of Area Research Articles

Vertical and horizontal variations in phytoplankton chlorophyll a in response to a looping super typhoon

AbstractPrevious studies suggested that the increase in surface chlorophyll a (Chl a) is due to nutrient upwelling or to the upward mixing of the subsurface Chl a maximum layer under the influence of tropical cyclones, while often ignoring the influence of the subsurface Chl a minimum layer and horizontal advection on Chl a. In this study, we show the important roles of the upward mixing of the subsurface Chl a minimum layer, horizontal advection, as well as the upwelling of the subsurface Chl a maximum layer, taking a looping super typhoon “Saola” in the northwest Pacific in August 2023 as an example. The temporal and spatial changes of Chl a and its physical properties were investigated by combining satellite, Argo, reanalysis, and model data. The results indicate that the combined effects of the upwelling of the subsurface Chl a maximum layer caused by wind stress curls and concurrent near‐surface wind mixing were responsible for the surface Chl a increase in the looping area during the typhoon, while the 13% increase in the depth‐integrated Chl a after the typhoon is mainly due to the nutrients brought by upwelling and subsequent biochemical processes. In the edge area affected by the typhoon, the surface Chl a decrease during the typhoon was mainly due to the upward mixing of the subsurface Chl a minimum layer (the effect of upwelling in this area is relatively weak). Furthermore, the horizontal advection led to a continuous surface Chl a decrease in the edge area after the typhoon. These findings could enhance understanding of Chl a dynamics post‐tropical cyclones, aiding marine ecosystem prediction.

Synthesis of binder-free hybrid Ni-Co-Se@NiS2 nanostructures as highly active and durable electrocatalyst for hydrogen evolution reaction in alkaline media and Seawater

The Ni-Co-Se structures have been widely examined as an electrocatalyst for the hydrogen evolution reaction (HER). Despite the excellent electrical transportability, they suffer from low profusion of active electrocatalytic sites as well as poor long-term durability. Herein, we demonstrated Nickel-Disulfur doping in Ni-Co-Se as an effective method to simultaneously elevate electrocatalytic activity and stability. In this study, the preparation and optimization of the Ni-Co-Se@NiS2 core–shell structure were discussed using hydrothermal and electrodeposition processes. The electrocatalytic activity of the synthesized samples was investigated in both 1 M KOH solution and Seawater. The results of the electrochemical and microstructural investigations showed that the electrodeposition of NiS2 on Ni-Co-Se under the condition of pulsed potential with a frequency of 0.01 Hz by creating a dual micro-nanometric structure with a high edge area, needed only 73 and 81 mV of overpotentials to achieve a current density of 10 mA.cm2 in KOH and Seawater, respectively, as well as continuous stable operation over 30 h. The excellent kinetics with only 1.7 Ω.cm2 charge transfer resistance reached 300 mV overpotential, the high electrochemically active surface area (ECSA) equal to 1900 cm2, and a turnover frequency (TOF) value of 0.160 s−1 at 140 mV indicate the promising electrocatalytic HER performance of the Ni-Co-Se@NiS2 catalyst. This work introduced a novel strategy for the design and synthesis of high-level selenide-based HER catalysts.

Landscape connectivity loss after the de-escalation of armed conflict in the Colombian Amazon (2011–2021)

Rapid deforestation has been well-documented in Colombia after the 2016 peace agreement with FARC. While many analysis using remote sensing identify land cover change, structural connectivity variables are less studied for understanding landscape transformation. In this work, we used data from the Landsat archive from 2011 to 2021, the Continuous Change Detection and Classification algorithm (CCDC), and Morphological Spatial Pattern Analysis (MSPA) to analyze deforestation, land cover change, and landscape connectivity in northwestern Colombia’s Amazon. We examined the spatial patterns in three specific subsets in the Colombian arc of deforestation, with a special focus on the surroundings of the National Natural Park Serranía de Chiribiquete. Our results confirm changes in structural connectivity linked to pasture expansion from the conversion forest to pasture during the analyzed period showing changes in the borders of Serranía de Chiribiquete National Park along rivers and roads, where cattle is transported. Before 2016, the average annual deforested area in the three study areas was 27.93 km²; after 2016, this number increased to 73.36 km². The outcomes of our study contribute to an improved understanding of pasture dynamics. They can aid decision-making in areas that play a key role in ecological networks necessary for long-term conservation efforts. Our quantitative assessments have revealed a temporal shrinking of the core area, indicative of a decline in forest cover. Concurrently, we observed an expansion of the edge and background areas, which is consistent with the proliferation of pastures. This study presents methodology and data in support of policy-making for sustainable land use and ecological connectivity to mitigate further environmental degradation in the area.

Behavior of hydrofoil cavitation in a slit channel

The paper presents the results of a cavitation in a slit channel study and offers an analytical description of cavity development. Special emphasis was placed on examining partial cavitation near a NACA 0012 hydrofoil (NACA – the National Advisory Committee for Aeronautics) inside slit channels of different geometries. Experimental investigation was carried out via high-speed imaging and the laser Doppler anemometry (LDA) method. The experimental data showed that the local flow velocity in hydrofoil leading edge area increased abruptly under arising cavitation. In addition, occurrence of cavitation raised flow velocity pulsation by 20%. In the case of a shorter channel, cavity growth occurred at higher cavitation numbers than for a longer channel. The cavity growth velocity was higher for a shorter channel. We showed that the tendency of partial cavitation development in the slit channel can be described as follows: L/C ∼ σ−1, where L is the cavity length; C is the hydrofoil chord; σ is the cavitation number; and parameter A changes as the slit channel length is varied. Comparison of cavitation development near hydrofoil at different attack angles α inside the slit channel with a three-dimensional (3D) cavitation tunnel was conducted. Cavitation in the slit channel occurred at lower σ/2α values compared to 3D cavitation flow around the hydrofoil. To directly compare lengths of the attached cavities arising in slit channels and 3D cavitation tunnels, an additional parameter is proposed, taking into account friction of the slit channel: K = λ·l/D. This parameter allowed us to quantitatively compare the characteristics of cavitating hydrofoils in slit channels and 3D tunnels. The paper provides the governing criteria of the cavitation in the slit channel. Our results propose the physical foundations for the development of cavities in the slit channel.

Analysis of cooling effects and measurement errors in water-cooled thermocouples for total temperature measurement in aviation engine combustion chambers

Accurate measurement of the total temperature in the main combustion chamber of an aviation engine is crucial for assessing engine performance. However, a significant challenge exists in balancing the heat transfer errors caused by the necessary cooling of the measuring device with measurement precision. The research employs a combination of numerical simulations and experimental methods to investigate this issue. The numerical simulations utilized the Reynolds-averaged Navier Stokes (RANS) coupled with a conjugate heat transfer approach to study the primary flow characteristics and heat transfer properties within the combustion chamber and the probe body. The experiments were conducted in a heat-calibration wind tunnel, validating the results of the numerical simulations. The results show that by implementing water cooling, the probe's body temperature can be reduced from 1200 °C in high-temperature conditions to 400 °C, with localized temperature imbalances still present in the edge areas of the probe. Tracing the cooling water path reveals that the vertical bends in the internal channels lead to an increase in localized pressure loss of the cooling water. The study quantitatively analyzes measurement errors caused by three heat transfer modes: radiation, convection, and conduction. In low-load conditions of the combustion chamber, heat conduction plays a dominant role, with measurement errors due to conduction reaching up to 70 % of the total measurement error. Radiation further increases the temperature measurement errors of the thermocouple's junctions near the chamber wall. As the combustion chamber temperature increases, entering high-load conditions, the cooling effect of water becomes limited, reducing conduction errors and increasing radiation errors. In these conditions, radiation errors constitute 60–70 % of the total measurement error. It suggests the importance of considering temperature corrections when using water-cooled temperature measurement devices. The research reveals several crucial insights regarding the performance and limitations of water-cooled thermocouples.

HIGH-FREQUENCY METHODS FOR COMPLEX AIRBORNE RADAR OBJECTS SCATTERING CHARACTERISTICS CALCULATING

The current state of radar to perform detection and recognition tasks development requires knowledge of a priori information about the secondary radiation of radar objects characteristics. Obtaining this information concerning the target is possible by means of physical or mathematical modelling. Information concerning radar objects obtained by conducting field and physical experiments is associated with significant material, organizational and time costs. Therefore, the method of mathematical modelling can be considered as the most affordable way to obtain information on scattering characteristics. This paper evaluates modern high-frequency methods for the scattering characteristics (secondary radiation) calculating on complex airborne radar objects by mathematical modelling. The calculation of the objects scattering characteristics with surface breaks is carried out by preliminary dividing the surface into a smooth part and edge areas of the surface. The corresponding mathematical relations obtained can be used to estimate the secondary radiation of a complex airborne radar object. The article defines the possibilities of modern high-frequency methods for calculating the scattering characteristics of complex airborne radar objects using mathematical modelling, namely: calculation of scattering characteristics by a smooth surface of a complex airborne radar object; calculation of the scattering characteristics by the edge local surface areas with a radio-absorbing coating of a complex airborne radar object. The scattering characteristics of objects with surface breaks are calculated by first dividing the surface into a smooth part and edge areas. To calculate the scattered field, Kirchhoff-type integral representations are used. Thus, the integration surface covering the scattered in these integral representations is chosen to coincide with the object's surface everywhere except for some edge area. The corresponding mathematical relations for scattering characteristics calculating on smooth and edge localized surface areas of a complex airborne radar object are obtained. The presented calculation methods application can contribute to obtaining a priori information (as required by the current state of radar development) concerning the scattering characteristics of complex airborne radar objects, taking into account such complicating factors as the heterogeneity of the boundary surface, the presence of radio-absorbing coatings, and taking into account their complex effect.

Evaluation of Ecological Sensitivity and Spatial Correlation Analysis of Landscape Patterns in Sanjiangyuan National Park

The Sanjiangyuan region, situated on the Qinghai–Tibetan Plateau, constitutes an exceptionally delicate ecological environment. Alterations in the region’s ecological landscape stem not only from natural factors but also from significant anthropogenic influences, exerting a notable impact on the sustainable economic and social development of the region’s middle and lower reaches. Consequently, investigating changes in the landscape pattern of Sanjiangyuan National Park holds paramount importance for comprehending the formation mechanism of spatial landscape distribution in the area. This study analyzes the ecological sensitivity and landscape pattern of Sanjiangyuan National Park in Qinghai Province, China, utilizing ArcGIS 10.8 and Fragstats 4.2. Employing the bivariate spatial autocorrelation analysis method, the research uncovers the spatial distribution characteristics between ecological sensitivity and landscape pattern, along with their aggregated change traits. The findings reveal that ecological sensitivity areas within the park encompass varying degrees, ranging from extremely sensitive to insensitive. The area of moderately sensitive zones in the Yellow River source region is 7279.67 km2 (39.17%), whereas the corresponding area in the Yangtze River source region is 32,572.34 km2 (36.30%). The eastern and northern parts of the Sanjiangyuan National Park exhibit significant landscape fragmentation. Ecological sensitivity varies markedly across different regions, with the southern and some northern areas showing higher sensitivity. In the Lancang River source park and the southern part of the Yellow River source park, the Largest Patch Index (LPI) and Ecological Sensitivity Index exhibit a high–high (HH) clustering pattern, indicating strong ecological connectivity in these areas. These regions also feature high Total Edge (TE), Number of Patches (NP), Patch Density (PD), and Edge Density (ED), indicating a complex landscape structure and abundant habitat edge areas. The study recommends restoring ecological connectivity in highly fragmented areas and implementing strict protection measures in sensitive regions to maintain ecosystem health and biodiversity. These findings provide a foundation for developing targeted ecological protection measures to enhance ecosystem health and biodiversity conservation in the area. This research aligns with several Sustainable Development Goals (SDGs), including Climate Action, Life on Land, and Clean Water and Sanitation, by promoting sustainable ecosystem management and biodiversity conservation.

HABITAT DAN PERILAKU SOSIAL BURUNG KAKATUA TANIMBAR (Cacatua goffiniana) DI DESA LORULUN KECAMATAN WERTAMRIAN KABUPATEN KEPULAUAN TANIMBAR

This research aims to determine the habitat conditions and behavior of the Cacatua goffiniana in Lorulun Village, Tanimbar Islands Regency. The method used for vegetation community data is a combination of the path method and plotted lines at 4 growth levels including seedlings, saplings, poles and trees, there are 15 paths with 75 plots in 3 observation blocks. Determining the location for observing the behavior of the Tanimbar Cockatoo (Cacatua goffiniana) was carried out using the concentrated point method and also the All Occurrences method. The research results show that the main habitat of the Tanimbar Cockatoo (Cacatua goffiniana) is primary and secondary tropical forests which have the availability of tall trees for nests and food sources. This bird is also found in plantations and forest edge areas, showing adaptability to habitat changes. The social behavior of Tanimbar cockatoos is very complex, showing a high level of intelligence, often seen in activities in small groups of 5-10 individuals. Social interactions between these individuals include various behaviors such as coordinating vocalization behavior, vocalization behavior feeling threatened, aggressive agonistic behavior, submissive agonistic behavior, affiliative behavior of feather probing, affiliative behavior of mutual probing, affiliative behavior of playing, affiliative behavior of perching. This research also notes the existence of a strong territorial behavior pattern, groups of Tanimbar parrots will defend their territory from other groups when food sources are abundant, these territorial boundaries become more flexible.

Rational design of CMUTs with annular electrodes for high ultrasonic emission via ESSE enabled stiffness adjustment

Capacitive micromechanical ultrasonic transducers (CMUTs) with high transmitting acoustic pressure are in urgent demand in the rapidly growing field of air-coupled and therapeutic ultras ound. However, most current CMUTs can rarely balance the performance improvement and batch fabrication capacity, which severely impedes their practical applications. This paper proposes novel CMUTs with annular electrodes that can implement significant improvement in multiple performances while featuring a simple structure and batch fabrication feasibility. The annular electrode configurated between the membrane edge and center areas can effectively soften the corresponding-area membrane stiffness through electrostatic spring softening effects, and leave the stiffness of the membrane central area unchanged, finally enabling the membrane to produce a piston-like deformation, thus improving average displacement and output acoustic pressure. A finite element method was employed to analyze the effect of annular electrodes on the CMUT main performance. The results demonstrated that the novel structure could achieve prominent enhancement in multiple performances, such as an average to maximum displacement rate of 0.46 (about 0.32 for conventional CMUTs), maximum improvements of 300%, 255%, and 11% in average displacement, acoustic pressure, and electromechanical coupling coefficients compared to those of conventional ones. Deep analyses of the variation of the main performances including acoustic pressure, receiving sensitivity, and collapse voltage suggested that an optimal electrode coverage range of 36% ∼ 55% can be used to achieve relatively high comprehensive performances. Meanwhile, the proposed CMUTs feature a simpler structure and fabrication process in comparison with previous ones, showing great promise in air-coupled and therapeutic ultrasound applications.

Fracture mechanisms of selective laser sintered parts manufactured in build direction

Selective laser sintering (SLS) is an additive manufacturing process that, in addition to rapid prototyping, is becoming increasingly popular to produce end-use parts. Predictable mechanical properties of the produced parts through this process is a desired primary goal. It has long been known that the mechanical properties especially the elongation at break of SLS components decrease in the build direction. In various test series with tensile specimen fabricated in build direction by SLS, it was found that, on the one hand, these have a very large scatter of the elongation at break, and, on the other hand, it was noticed that these frequently break outside the test range in the upskin radius. The upskin area describes regions that point in a positive build direction relative to the building plate. The fracture occurs at a point where, due to the specimen cross-section, a lower fracture stress occurs than in the test area of the specimen. This fracture leads to a much lower elongation at break than in the case of specimens that fracture in the test area. This study investigates which mechanism triggers this behavior. It turns out that different roughnesses can be determined in the upskin and downskin radius and different defects can be seen in the fracture surfaces, especially in the edge areas. It cannot be predicted based on surface roughness measurements or surface profiling exactly where, or in which layer the fracture occurs. However, the defects lead to a local stress spike, at which the failure of the specimen begins.

Edge-protected IDW-based DEM detail enhancement and 3D terrain visualization

Terrain visualization plays an important role in Digital Twin, geology, environmental science, and exploration. Generating 3D visualization results by the Digital Elevation Model (DEM) is an effective method. However, existing DEM 3D visualization methods generally lack sufficient detail to obtain good visual effects. Therefore, we propose a novel DEM detail enhancement and 3D terrain visualization method. Our method is based on the Contrast Limited Adaptive Histogram Equalization (CLAHE) algorithm and the edge-protected Inverse Distance Weighted (IDW) algorithm, and achieves 3D visualization of DEM data through a workflow of converting the raw DEM data into an image, followed by enhancement and detail optimization of the image, and finally converting the image into triangular meshes. The edge-protected IDW algorithm performs IDW interpolation optimization based on the Canny edge detector combined with the Otsu threshold optimization method to detect edge areas, achieving smooth transitions in the edge areas. Experiments show that our method generates detail-rich 3D visualization results after enhancing original DEM data. We also conducted an ablation study to provide a side-by-side comparison of each step. Our method can be further applied to many tasks, such as virtual reality, GIS, and geological exploration.

Carabid beetles in solar parks: assemblages under solar panels are severely impoverished compared to gaps between panel rows and edge areas

Renewable energies are a major tool to reduce greenhouse gas emissions and combat climate change. Among renewables, solar parks are a key technology and their expansion will strongly increase in the future. Hence, there is a great need for research regarding their impact on biodiversity. In this study, we investigated the importance of three solar parks in northern Germany as habitat for carabid beetles. More specifically, we determined how habitat characteristics (temperature, vegetation structure), species richness, activity densities and carabid beetle assemblages vary between different locations within solar parks: areas under solar panels “UNDR”, gaps between panel rows “BTW” and areas at the edge of solar parks “EDGE”. We found that UNDR strongly differed from BTW/EDGE in terms of habitat conditions, species richness and activity densities of carabid beetles. UNDR mainly provided habitat for a species- and individual-poor subset of species already present in BTW/EDGE and made only a small contribution to the total species richness of the investigated solar parks. BTW and EDGE, on the other hand, differed only slightly. Thus, the narrow gaps between the panel rows were of similar importance as a habitat for carabid beetles as the edge areas. Overall, the investigated solar parks—and thus also the more species-rich areas EDGE and BTW—almost exclusively provided habitat for widespread and common non-threatened generalists, while species of conservation concern were extremely rare.Implications for insect conservationThe low importance of UNDR for carabid beetles should be considered when assessing the biodiversity value of solar parks, since a large proportion of these facilities is covered with solar panels. Between panel rows and at the edge of solar parks, larger areas should be kept free from construction with solar panels in order to provide habitats for carabid beetles and other species groups. More research should be conducted on how to further improve solar parks for carabid beetles and overall biodiversity.

Reliability of glenoid measurements performed using Multiplanar Reconstruction (MPR) of Magnetic Resonance (MRI) in patients with shoulder instability

PurposeMeasurement of glenoid bone loss in the shoulder instability can be assessed by CT or MRI multiplanar imaging and is crucial for pre-operative planning. The aim of this study is to determine the intra and interobserver reliability of glenoid deficiency measurement using MRI multiplanar reconstruction with 2D assessment in the sagittal plane (MPR MRI).MethodsWe reviewed MRI images of 80 patients with anterior shoulder instability with Osirix software using MPR. Six observers with basic experience measured the glenoid, erosion edge length, and bone loss twice, with at least one-week interval between measurements. We calculated reliability and repeatability using the intra-class correlation coefficient (ICC) and minimal detectable change with 95% confidence (MDC95%).ResultsIntra and Inter-observer ICC and MDC95% for glenoid width and height were excellent (ICC 0,89-0,96). For erosion edge length and area of the glenoid were acceptable/good (ICC 0,61-0,89). Bone loss and Pico Index were associated with acceptable/good ICC (0,63 -0,86)) but poor MDC95% (45 - 84 %). Intra-observer reliability improved with time, while inter-observer remained unchanged.ConclusionThe MPR MRI measurement of the anterior glenoid lesion is very good tool for linear parameters. This method is not valid for Pico index measurement, as the area of bone loss is variable. The pace of learning is individual, therefore complex calculations based on MPR MRI are not resistant to low experience as opposed to true 3D CT

The dominant influencing factors of desertification and ecological risk changes in Qinghai Area of Qilian Mountains National Park: Climate change or human activity?

Transitional features of desert environments partially determine the risks associated with ecosystems. Influenced by climate change and human activities, the variability and uncertainty of desertification levels and ecological risks in the Qinghai Area of Qilian Mountain National Park (QMNPQA) has become increasingly prominent. As a critical ecological barrier in northwest China, monitoring desertification dynamics and ecological risks is crucial for maintaining ecosystem stability. This study identifies the optimal monitoring model from four constructed desertification monitoring models and analyzes spatiotemporal changes in desertification. The spatial and temporal changes in ecological risks and their primary driving factors were analyzed using methods such as raster overlay calculation, geographic detector, cloud model, and trend analysis. The main conclusions are as follows: The desertification feature spatial model based on GNDVI-Albedo demonstrates better applicability in the study area, with an inversion accuracy of 81.24%. The levels of desertification and ecological risks in QMNPQA exhibit significant spatial heterogeneity, with a gradual decrease observed from northwest to southeast. From 2000 to 2020, there is an overall decreasing trend in desertification levels and ecological risks, with the decreasing trend area accounting for 89.82% and 85.71% respectively, mainly concentrated in the southeastern and northwestern parts of the study area. The proportion of areas with increasing trends is 4.49% and 7.05% respectively, scattered in patches in the central and southern edge areas. Surface temperature (ST), Digital Elevation Map (DEM), and Green normalized difference vegetation index (GNDVI) are the most influential factors determining the spatial distribution of ecological risks in QMNPQA. The effects of management and climatic factors on ecological risks demonstrate a significant antagonistic effect, highlighting the positive contributions of human activities in mitigating the driving effects of climate change on ecological risks. The research results can provide reference for desertification prevention and ecological quality improvement in QMNPQA.

Non-solvent displacement nonaqueous precipitation fabrication of novel foldable HAp ceramic paper without fiber and its performance

Novel highly foldable HAp ceramic paper with fire retardancy but without fiber was fabricated via novel non-solvent displacement nonaqueous precipitation strategy. The obtained HAp ceramic paper, characterized by highly smooth and glossy, is characterized via X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), curlability test, moisture absorbency and Pb2+ removal performance test. The results show that the ceramic paper is very straight, uniform, and smooth with high curlability and low moisture absorption. No fiber is detected in the ceramic paper. No defect is either detected except for at the edge area. The HAp ceramic paper is grown along the (002) crystal plane of the hydroxyapatite phase from hexagonal plate like single crystal sheets. The ceramic paper loaded for four times has formed a clear four-layer-structured, with a total thickness of about 832 nm. The thickness of each layer is very uniform, with an average thickness of about 208 nm per layer. HAp ceramic paper has excellent Pb2+ ions removal performance, curling performance, moisture absorption performance and flame retardant performance. These performances confirm this novel HAp ceramic paper has superior properties over the traditional ceramic paper with fibers and shows great application prospect in various fields.

ERSegDiff: a diffusion-based model for edge reshaping in medical image segmentation

Medical image segmentation is a crucial field of computer vision. Obtaining correct pathological areas can help clinicians analyze patient conditions more precisely. We have observed that both CNN-based and attention-based neural networks often produce rough segmentation results around the edges of the regions of interest. This significantly impacts the accuracy of obtaining the pathological areas. Without altering the original data and model architecture, further refining the initial segmentation outcomes can effectively address this issue and lead to more satisfactory results. Recently, diffusion models have demonstrated outstanding results in image generation, showcasing their powerful ability to model distributions. We believe that this ability can greatly enhance the accuracy of the reshaping results. This research proposes ERSegDiff, a neural network based on the diffusion model for reshaping segmentation borders. The diffusion model is trained to fit the distribution of the target edge area and is then used to modify the segmentation edge to produce more accurate segmentation results. By incorporating prior knowledge into the diffusion model, we can help it more accurately simulate the edge probability distribution of the samples. Moreover, we introduce the edge concern module, which leverages attention mechanisms to produce feature weights and further refine the segmentation outcomes. To validate our approach, we employed the COVID-19 and ISIC-2018 datasets for lung segmentation and skin cancer segmentation tasks, respectively. Compared with the baseline model, ERSegDiff improved the dice score by 3%–4% and 2%–4%, respectively, and achieved state-of-the-art scores compared to several mainstream neural networks, such as swinUNETR.

Preliminary clinical observation and analysis of structural changes of optic nerve head in glaucoma patients after visual training

Objective: To investigate the effect of virtual reality visual training on remodeling optic nerve structures of glaucoma patients and analyze the influencing factors of visual training effect. Methods: A prospective non-randomized controlled trial was conducted. Glaucoma patients who presented to the Department of Ophthalmology, Beijing Shijitan Hospital between October 2021 and October 2022 were collected and divided into the training group or the control group according to their intentions. The training group accepted 3 months of visual training, while the control group did not. Optical coherence tomography was used to examine the disc edge area, cup volume, disc area, cup-to-disc ratio, and other parameters of the optic disc of both eyes of the patients at enrollment and after 3 months, and the changes of each parameter in the two groups were analyzed. Multivariate analysis was performed in the training group to investigate the effects of sex, age, visual field index, and mean defect on visual disc structure changes during visual training. Results: A total of 53 glaucoma patients (101 eyes) were included in the final analysis, among which the training group consisted of 27 cases (51 eyes), with 19 males and 8 females, and the age range was 48.0 (40.0, 61.0) years old. The control group comprised 26 cases (50 eyes), with 26 males and 11 females, and the age range was 54.0 (38.0, 63.0) years old. Compared with the control group, the deviation of cup volume was -0.006(-0.050, 0.015)mm3 (P<0.05), and the deviation of disc edge area was 0.00(-0.04, 0.05)mm2 (P<0. 05)in the visual training group after 3 months of visual training. The gender (OR=4.217, 95%CI=1.188-14.966) may be the influence factor of rim area. While,the mean defect (OR=1.526, 95%CI=0.245-9.491) was not that influential on rim area change. Conclusions: Visual training can increase the disc area and decrease the optic cup volume of the optic nerve in glaucoma patients. The rim area may be increased more easily after visual training in male glaucoma patients.

Greenbelt's impact on urban forest habitat: Insights from morphological analysis in quantifying conservation effects

Urban forests play a crucial role in preserving biodiversity in highly urbanized areas by providing habitats for various species and promoting ecological connectivity. However, managing urban forests presents challenges such as low habitat quality and fragmentation risks. To address these challenges, protected areas serve as a fundamental policy tool. This study analyzes the effect of Greenbelt areas, protected spaces within urban settings, on future land-use and habitat changes. Through morphological analysis of forest areas, this study attempts to analyze the current status of habitats in cities affected by fragmentation and derive the effects of green belts, thereby presenting the direction of biodiversity conservation for city habitats. The Slope, Land-use, Excluded area, Urban, Transportation, Hillshade (SLEUTH) land-use change model was used to predict future land-use changes by applying a scenario that adjusts weights within the Greenbelt areas. In addition, the Morphological Spatial Pattern Analysis (MSPA) Tool was used to derive changes by habitat type, which aided in deriving the implications of the Greenbelt regulation on the habitat. Our findings indicate that Greenbelt regulation effectively prevents the reduction of critical Core areas and minimizes damage to Islets, small patches. Comparisons between Core and Edge areas reveal that Edge areas are more vulnerable to development, and the impact of regulating the Greenbelt area is significant. In addition, Greenbelt regulations can help prevent habitat fragmentation by reducing Perforation, which creates cavities within Core areas. This study quantitatively demonstrated that the Greenbelt can play an important role not only in preventing urban expansion but playing an important role in habitat conservation in cities.

Spatiotemporal Evolution of Land Cover and Landscape Ecological Risk in Wuyishan National Park and Surrounding Areas

Previous studies on national park conservation have focused mainly on their internal areas, and few studies have focused on national parks and their surrounding areas as unified entities. Therefore, the investigation of land cover and landscape ecological risks in national parks and surrounding areas is essential for overall ecosystem protection and regional sustainable development. This study examines the spatiotemporal evolution of land cover and its landscape ecological risk in Wuyishan National Park, China, and its surrounding areas (WNPSA) from 1990 to 2020. The results show that (1) the land cover of WNPSA from 1990 to 2020 predominantly exhibited a consistent decline in forested areas, paralleled by an augmentation in farmland and impervious surface areas. The center of standard deviation ellipse of impervious surfaces has been progressively moving further south in tandem with the expansion of these surfaces, primarily located within the county town of Fujian Province. (2) The Wuyishan National Park (WNP) areas were dominated by low values of landscape index, and the high value areas in the park were mainly located at the provincial boundary area, with a gradual narrowing during 1990–2020, suggesting a decrease in landscape heterogeneity within the park. High value areas in the surrounding areas mainly occurred in areas with clustered impervious surfaces (e.g., the county town), where part of them located in Wuyishan City have spread to the edge area southeast of WNP. (3) From 1990 to 2020, the lowest-risk areas continue to expand. However, as the medium-risk zone of the adjacent region extends into the edge of the national park, the low risk zone within the national park exhibits a trend from continuous to separate with the neighboring low risk zone. This led to an escalating stress effect on the ecological security of both the adjacent regions and the national park’s boundary areas due to land cover changes.

Influence of Microstructure on the Mechanical Properties and Polishing Performance of Large Prehardened Plastic Mold Steel Blocks

The microstructures throughout a 696 × 1360 mm cross-section of an ISO 1.2738 prehardened steel block for a plastic mold were characterized via optical and electron microscopy and electron backscatter diffraction. The hardness, strength, and polishing performance of the steel block were also tested. The results showed that the microstructure of the steel bloom from the edge to the core consisted of tempered sorbite, tempered bainite, and pearlite microstructures. Abnormal upper bainite and coarse carbides were also found. The bloom sections with hardness values of 37.4 to 39.3 HRC comprised tempered sorbite and bainite. The hardness of the core was approximately 36.5 HRC due to the presence of pearlite. The tensile and yield strengths were the same in the edge and middle areas mainly owing to tempered sorbite. The polishing performance was affected by the microstructure. Tempered sorbite produced the best polishing performance due to its fine and uniform microstructure, whereas that of tempered bainite and pearlite, which contained large carbide particles and mixed phases, was worse.