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Polarization-dependent photoemission electron microscopy (PD-PEEM) exploits spatial variation in the optical selection rules of materials to image domain formation and material organization on the nanoscale. In this Perspective, we discuss the mechanism of PD-PEEM that results in the observed image contrast in experiments and provide examples of a wide range of material domain structures that PD-PEEM has been able to elucidate, including molecular and polymer domains, local electronic structure and defect symmetry, (anti)ferroelectricity, and ferromagnetism. In the end, we discuss challenges and new directions that are possible with this tool for probing domain structure in materials, including investigating the formation of transient ordered states, multiferroics, and the influence of molecular and polymer order and disorder on excited state dynamics and charge transport. [ABSTRACT FROM AUTHOR]

Traveling wave parametric amplifiers (TWPAs) offer the most promising solution for high gain, broadband, and quantum noise limited amplification at microwave frequencies. Experimental realization of TWPAs has proved challenging with often major discrepancies between the theoretically predicted and the measured gain performance of the devices. Here, we extend the conventional modeling techniques to account for spatial variation in the surface impedance of the thin film and the parametric sum-frequency conversions effect, which subsequently results in accurate reproduction of experimental device behavior. We further show that such an analysis may be critical to ensure fabricated TWPAs can operate as designed. [ABSTRACT FROM AUTHOR]

Electrospinning is a cost-effective but very intricate method of producing polymeric nanofibers at room temperature. Unfortunately however, it is extremely difficult to predict the diameter or other properties of the fibers produced via electrospinning a prior. In this paper, we present a new approach to simulate fiber formation during electrospinning. Our work builds on the mathematical framework that was originally developed by Reneker and Yarin in 2000. Our approach incorporates the 3D electrostatic field that surrounds the fiber in a Lagrangian discrete particle tracking algorithm that tracks the trajectory of the fiber in air and predicts its deposition velocity and diameter. We investigate the effects of electrostatic field spatial variation on fiber electrospinning and compare our results with those obtained using a constant electrostatic field, the traditional approach, and with experiments (conducted using polyurethane). We considered three different electrospinning configurations of single-needle-plate-collector, single-needle-drum-collector, and two-needles-drum-collector to investigate how different electrostatic fields impact fiber formation. The computational model developed in this work helps to advance the current state of the art in modeling the electrospinning process. [ABSTRACT FROM AUTHOR]

Budd Chiari syndrome is a potentially treatable disease, and imaging is the key to its diagnosis. Clinical presentations may vary, ranging from asymptomatic to fulminant disease. Subacute BCS is the most common type encountered in clinical practice, characterized by ascites, hepatosplenomegaly, dilated abdominal wall veins, and varicosities in the lower limb and scrotum. While hepatic vein thrombosis is the leading cause in the West, membranous and short segmental occlusion are predominant in the Asian populations. These geographical variations have an impact on the treatment algorithm in managing BCS. Anticoagulation alone often fails to prevent disease progression, demanding further interventional therapy. Interventional therapy carries a lower morbidity and mortality than surgery. Anatomical recanalization and portosystemic shunting form the basis of endovascular management. Membranous or short-segment occlusion are best treated by angioplasty, which restores the physiological venous outflow and possibly disease reversal. Suboptimal results with angioplasty require stenting. Transjugular intrahepatic shunt (TIPS) or direct IVC to portal vein shunt (DIPS) decompresses the portal pressure and reduces the sinusoidal congestion, which in turn diminishes hepatocellular damage and hepatic fibrosis. Despite its ability to modify the disease course, TIPS carries several procedure and shunt-related complications, mainly hepatic encephalopathy. Thus, anatomical recanalization precedes TIPS in the traditional step-up approach in managing BCS. However, this concept is challenged by some authors, necessitating future reseach. TIPS is a valid bridge therapy in BCS with acute live failure awaiting liver transplantation. Despite all, interventional therapies fail in a subset of BCS patients, leaving them with only option of liver transplantation. [ABSTRACT FROM AUTHOR]

This study examines the impact of digital progress on the green development of China's cultural industries, a critical factor in improving their environmental sustainability. We applied the superefficient SBM model, incorporating undesirable outputs, to evaluate the green development efficiency of the cultural industry in 31 Chinese provinces from 2013 to 2021. The research also involved using the ArcGIS tool to investigate spatial patterns and temporal changes in the efficiency of cultural industries across these provinces. Furthermore, we developed an index to measure the digital advancement of Chinese provinces and its influence on the cultural industry's green development efficiency. Our findings indicate a three-phase evolution of green efficiency in China's cultural industries: an initial rise, a period of decline, and a recent upswing, reflecting a pattern of fluctuation and recovery. Significant spatial variation in green development efficiency is noted among provinces, with more efficient outcomes in lower-latitude areas. Importantly, our analysis indicates that increasing digitization levels positively affect the green development efficiency of China's cultural industries. [ABSTRACT FROM AUTHOR]

• The concentration of phthalates in the Yellow River is higher. • DMP, DEP, and DiBP were the most frequently encountered components. • Control of construction land release and lake pollution sources is critical. • DNOP and DiBP demonstrate low to moderate risk concentrations. Phthalate esters (PAEs), recognized as endocrine disruptors, are released into the environment during usage, thereby exerting adverse ecological effects. This study investigates the occurrence, sources, and risk assessment of PAEs in surface water obtained from 36 sampling points within the Yellow River and Yangtze River basins. The total concentration of PAEs in the Yellow River spans from 124.5 to 836.5 ng/L, with Dimethyl phthalate (DMP) (75.4 ± 102.7 ng/L) and Diisobutyl phthalate (DiBP) (263.4 ± 103.1 ng/L) emerging as the predominant types. Concentrations exhibit a pattern of upstream (512.9 ± 202.1 ng/L) > midstream (344.5 ± 135.3 ng/L) > downstream (177.8 ± 46.7 ng/L). In the Yangtze River, the total concentration ranges from 81.9 to 441.6 ng/L, with DMP (46.1 ± 23.4 ng/L), Diethyl phthalate (DEP) (93.3 ± 45.2 ng/L), and DiBP (174.2 ± 67.6 ng/L) as the primary components. Concentration levels follow a midstream (324.8 ± 107.3 ng/L) > upstream (200.8 ± 51.8 ng/L) > downstream (165.8 ± 71.6 ng/L) pattern. Attention should be directed towards the moderate ecological risks of DiBP in the upstream of HH, and both the upstream and midstream of CJ need consideration for the moderate ecological risks associated with Di-n-octyl phthalate (DNOP). Conversely, in other regions, the associated risk with PAEs is either low or negligible. The main source of PAEs in Yellow River is attributed to the release of construction land, while in the Yangtze River Basin, it stems from the accumulation of pollutants in lakes and forests discharged into the river. These findings are instrumental for pinpointing sources of PAEs pollution and formulating control strategies in the Yellow and Yangtze Rivers, providing valuable insights for global PAEs research in other major rivers. [Display omitted] [ABSTRACT FROM AUTHOR]

• Remarkable spatiotemporal pattern of N2O concentrations and fluxes were observed. • Factors controlling N2O emission vary across lake zones and seasons. • Seasonally frozen eutrophic shallow lakes in cold regions can be a source of N2O. • Northern part of the lake near the drained inlet is a "hotspots" for N2O emission. Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide (N 2 O), while regional and global estimates have remained imprecise. This due to a lack of data and insufficient understanding of the multiple contributing factors. This study characterized the spatiotemporal variability in N 2 O concentrations and N 2 O diffusive fluxes and the contributing factors in Lake Wuliangsuhai, a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid climate. Dissolved N 2 O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L, displaying significant spatiotemporal variations. The lowest and highest concentrations were measured in summer and winter, respectively. The spatial distribution of N 2 O flux was consistent with that of N 2 O concentrations. Additionally, the hotspots of N 2 O emissions were detected within close to the main inflow of lake. The wide spatial and temporal variation in N 2 O emissions indicate the complexity and its relative importance of factors influencing emissions. N 2 O emissions in different lake zones and seasons were regulated by diverse factors. Factors influencing the spatial and temporal distribution of N 2 O concentrations and fluxes were identified as WT, WD, DO, Chl-a, SD and COD. Interestingly, the same factor demonstrated opposing effects on N 2 O emission in various seasons or zones. This research improves our understanding of N 2 O emissions in shallow eutrophic lakes in cold and arid areas. [Display omitted] [ABSTRACT FROM AUTHOR]

A general analytical solution is worked out for the classical one-dimensional steady-state advection dispersion equation (ADE) for a heterogeneous soil with a compressible advective fluid. The solution can account for any well-defined boundary conditions at the ends of a transport space and can also consider any arbitrary nonlinear coefficients in the decay and sorption terms of the ADE. It can also accommodate any user specified spatial variations of the parameters of the ADE, including spatial variations of the degradation rates in the liquid and solid phases as well as spatial variations of the source term in the liquid phase. The validity of the proposed solution is extensively checked by comparing with analytical and experimental works of others for a few relatively simple transport situations. Also, a numerical check on it has also been carried out utilizing the HYDRUS-1D numerical codes. The study shows that advection dispersion transport of a solute in a heterogeneous soil may be greatly impacted by the spatial variations of the soil-hydraulic parameters of the soil; thus, the assumption of soil homogeneity in a heterogeneous soil for modelling solute transport through it may lead to substantial modelling errors at times. The developed solution also shows that steady-state solute transport dynamics in a soil is quite sensitive to the parameters of the ADE like advective velocity, partition coefficient, degradation rates in the liquid and solid phases and zero order production rate, and that a slight change in either of these parameters may affect the transport process on the soil in a significant way. The study has revealed that solute transport dynamics with a compressible fluid in many instances may be significantly different from that with an incompressible one. The study also showed that the nature of the sorption isotherm associated with a transport process alone may affect it in a significant way. Further, the study, expectedly, has also shown that the solute concentration profile of a transport process is fairly sensitive to the Peclet number associated with it and that the concentration profile of an advection dominated process may be substantially higher than that of a diffusion dominated process. [ABSTRACT FROM AUTHOR]

Overpressure prediction for exploratory drilling has become robust in most basins with increasing well control, high-quality seismic datasets, and proactive real-time overpressure monitoring while drilling. However, accurate overpressure prediction remains challenging in offshore Northwest Borneo despite several decades of drilling experience. This paper focuses on two exploration wells drilled by Brunei Shell Petroleum 40 years apart that faced similar challenges with overpressure prediction and well control. An integrated lookback study is attempted using seismic and well-log data to explore the causes of the unsatisfactory Pore Pressure Prediction (PPP) outcome in pre-drill and real-time operation settings for these wells. Our study indicates that the misprediction of overpressures is due to real differences in shale pressure (basis of pre-drill work and monitoring) and sand pressure (source of drill kick and well control challenges) due to large-scale vertical leak or expulsion of deep-seated fluids into pre-compacted normally pressured overlying sediments in several regions through a mix of shear and tensile failure mechanisms. Such migrated fluids inflate the sand pressure in the normally compacted shallower sequences with the shale pressure remaining low. A predictive framework for upward fluid expulsion was attempted but found impracticable due to complex spatial and temporal variations in the horizontal stress field responsible for such leakage. As such, it is proposed that these migratory overpressures are essentially 'unpredictable' from conventional PPP workflows viewed in the broad bucket of compaction disequilibrium (undercompaction) and fluid expansion (unloading) mechanisms. Further study is recommended to understand if such migrated overpressures in the sand can produce a discernible and predictable geophysical or petrophysical signature in the abutting normally compacted shales. The study highlights the possibility of large lateral variability in the sand overpressure within the same stratigraphic unit in regions with complex tectonostratigraphic evolution like Northwest Borneo. [ABSTRACT FROM AUTHOR]

Background: Stroke is a leading cause of premature death worldwide. Spatial-temporal characteristics are important for evidence-based stroke care planning and resource allocation. However, long-term global variations of stroke are still lacking. Objective: To identify the characteristics of the global spatial distribution of age-standardized mortality rate (ASMR) due to stroke during 2000–2021, thereby informing the efficient allocation of global health care resources. Methods: Based on age-standardized mortality rate (ASMR) due to stroke from the Global Health Estimates database, we analyzed stroke variation from 2000 to 2021 in 183 countries worldwide using Moran's I, Getis-Ord Gi*, and Standard Deviation Ellipse. We stratified the 183 countries into different income groups according to World Bank classification to identify the socioeconomic influence on stroke mortality. Results: The result showed that ① From 2000 to 2021, the number of stroke deaths increased worldwide, but the AMSR due to stroke showed a downward trend; ② The spatial distribution of the global AMSR due to stroke varies across geographic regions. with the highest in Asia and southern Africa, and the lowest in Europe and North America; ③ The spatial pattern of hot and cold spots of AMSR due to stroke remained relatively stable from 2000 to 2021, with the greatest changes in Africa and Asia; ④ Generally, countries belong to higher economic groups have lower stroke mortality rate, and this pattern persisted throughout the study period. Conclusions: Our findings provide evidence on spatial variations of stroke mortality worldwide over 20 years, and are informative on evidence-based allocation of medical resources globally. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

Cement-treated ground often possesses significant spatial variation in strength and stiffness. Studies on the detection and stiffness measurement of weak zones in cement-treated ground using seismic geophysical methods remain limited to date. The work examines the feasibility of using seismic travel time tomography to detect and measure the stiffness of weak zones in cement-treated ground, through 1-g modelling of a cross-hole setup with weak zones of prescribed sizes and stiffnesses. Using bender elements as transmitters and receivers, shear wave velocity profiles across the weak zones are mapped. Sizes, locations, and stiffnesses of the weak inclusions are also inferred from shear wave travel times using GeoTomCG. The results indicate that although the sizes and locations of weak zones can be reliably detected using first-arrival time-picking, the stiffnesses is significantly over-estimated. The latter is due to the arrival of the diffracted waves around the weak zone masking the arrival of the transmitted waves. A modified time-picking method, using the wavelet transform, is developed and is shown to give more reliable stiffness measurements of the weak zone, but not the shape. Combining direct and wavelet time-picking allows the sizes, shapes, locations, and stiffnesses of the weak zones to be more reliably resolved. [ABSTRACT FROM AUTHOR]

Marine nitrogen cycle ultimately depends on the biological responses of oceanic microbial communities. It indirectly regulates primary production and influences the strength of the biological pump, which contributes to the oceanic uptake of atmospheric carbon dioxide (CO2). As the microbial community structure and functional capacities remain underestimated in terms of temporal and geographical coverage in the Baltic Sea, our understanding of the nitrogen cycle with respect to ecosystem functioning and climate change is limited. Therefore, in this study, we investigated the seasonal and spatial structure of microbial community abundance involved in the nitrogen loss (denitrification, anammox), reduction processes (dissimilatory nitrate reduction (DNR), dissimilatory nitrite reduction to ammonium (DNRA), and oxidation process (nitrification) in the Baltic Proper (Bornholm Deep, Gdańsk Deep, and Gotland Deep). Specifically, we focused on waters below the halocline at depths ranging from 75 to 135 m, characterized by changeable oxygen conditions. The potential of selected nitrogen processes was resolved by mapping raw reads against nitrogen cycle genes identified in de novo assembled metagenomes. Taxonomic analysis of bacterial and archaeal communities, based on paired-end raw reads, revealed that nitrification, DNR, and denitrification potential were primarily associated with the Nitrosopumilaceae and Thioglobaceae families within these phyla. Ammonia oxidation products likely fueled the production of nitrous oxide (N2O), with nitric oxide reductase (NOR)—an enzyme encoded by the Thioglobaceae genome—being responsible for further reduction. Anammox-related genes were not present within sites, thus denitrification pathway enzymes, namely, NOR and N2O reductase (NOS) were responsible for nitrogen loss. At all sites, genes encoding nitrogen reduction enzymes were most abundant, while the presence of NOS encoding genes was found in Bacteroidetes and Proteobacteria phyla within all sites. Our findings revealed no significant spatial variation, suggesting that the studied ecosystem exhibits a consistent nitrogen processing capacity across different locations. However, seasonality emerged as a key factor, as changes in nutrient and oxygen conditions throughout the year significantly influence microbial activity and the associated nitrogen-cycling processes. [ABSTRACT FROM AUTHOR]

Introductions: As a key link in the development of modern agriculture, the transfer of arable land is regarded as a strategic measure to improve agricultural production efficiency and ensure national food security. Although the transfer of arable land has been widely implemented nationwide, its specific impact on agricultural production and farmers' income varies in different regions. The analysis of regional differences in agricultural land transfer in existing literature is still insufficient. Methods: This study is based on data from important agricultural areas along the coast of Guangdong Province in 2013, 2018, and 2023, and uses stepwise regression models and geodetectors to analyze the factors affecting spatial differentiation of agricultural land transfer. Result: Cultivated land transfer in Zhanjiang, Maoming, and Yangjiang cities exhibits distinct spatial distribution characteristics, forming a gradient pattern that increases from east to west. In single-factor analysis, factors such as irrigation conditions, agricultural output value, urbanization level, electricity supply, and centralized water supply projects have a particularly prominent impact on farmland transfer. Multi-factor interaction analysis reveals that centralized water supply projects, agricultural film usage, urbanization rate, agricultural GDP, and irrigation area have a significant impact on farmland transfer. Discussion: This study suggests that the spatial differentiation of agricultural land transfer is the result of the interaction between production characteristics, economic characteristics, population characteristics, and input characteristics. Next, it is necessary to further improve data collection, optimize research methods, and comprehensively consider more factors that may affect cultivated land transfer. [ABSTRACT FROM AUTHOR]

To determine the excess of dissolved dinitrogen gas (ΔN2 > 0 indicates the loss of bioavailable dissolved nitrogen) in the water column of the Baltic Proper, we measured N2/Ar ratios below the halocline at 19 stations during different seasons between 2017 and 2021. ΔN2 concentrations below the halocline ranged from 1.0 to 32.6 µmol L-1 for all seasons and sites. A significant spatial difference in ΔN2 (p = 0.0001) was observed, with the highest values found in the Gotland Deep. The seasonal changes in ΔN2 were statistically significant (p = 0.005) with the highest concentrations observed in winter. To our knowledge, this is the first study showing the variability of ΔN2 on a large scale in the Baltic Proper. Our findings suggest that the cumulative loss of bioavailable nitrogen via denitrification and anammox is an important mechanism in the Baltic Sea nitrogen cycle. The accumulated signal of N2 production is, however, not uniform across the Baltic Proper, exhibiting significant seasonal and spatial variabilities. This calls for future, investigations on a broad spatial scale and a seasonal resolution which focus on denitrification and anammox rates in the water column, by utilizing a consistent methodological approach. It is essential to ensure an accurate representation of the nitrogen loss, which in turn is important for managing eutrophication and maintaining a good environmental status in the Baltic Sea. [ABSTRACT FROM AUTHOR]

In this study, two Category 3 carbonaceous particles (RB-CV-0008 and RB-CV-0031) among more than 700 Hayabusa-returned particles were analyzed by molecular imaging using desorption electrospray ionization–high-resolution mass spectrometry (desorption electrospray ionization (DESI)–high-mass-resolution mass spectrometry (HRMS)) with an electrically charged methanol spray. RB-CV-0031 was unfortunately lost during the analysis; however, 176 positive ions (m/z 70–1000) were successfully identified from the surface of RB-CV-0008. The chemical compositions of these ions were assigned using their exact masses, and CHNO and CHO compounds were abundant in both number and total ion intensity. The ions showed varying spatial distributions, which could be classified into six patterns, and their chemical compositions were different between the distribution patterns. Furthermore, the ions were predominantly detected from the region surrounding the main body of the particle, where tiny particles that were likely broken up during handling were observed. This result suggests that RB-CV-0008 consists of more than two materials with different solubilities in methanol. Furthermore, several homologous compounds containing the C3H6O unit (at 58.0418 amu) were found in the identified ions from RB-CV-0008 using a mass defect (MD) plot. Among the possible contaminants analyzed in this study, the features of the positive ions identified by DESI–HRMS imaging and energy-dispersive spectroscopy (EDS) of RB-CV-0008 most closely resembled those of Nylon-6. These results suggest that some of the moieties, including the side chains corresponding to the C3H6O unit of RB-CV-0008, resembled those of Nylon-6 and polypropylene glycol (PPG), but the carbon skeleton differed between RB-CV-0008 and those materials. Our results indicate that RB-CV-0008 likely contains a mixture of different materials, such as polyamide and PPG. This study represents first comprehensive investigation of the soluble organic matter (SOM) characteristics of Category 3 particles by in situ analysis. The spatial distribution and ion species detected in this study indicate that the RB-CV-0008 particles have heterogeneous moieties with different solubilities in methanol and/or ionization efficiency and different chemical compositions. This study supports previous studies suggesting that Category 3 particles are derived from terrestrial materials and have multiple origins. [ABSTRACT FROM AUTHOR]

Due to factors that include systematic sensor delay, it is difficult for synthetic aperture radar (SAR) satellite stereo positioning to meet the requirements of large-scale mapping. In traditional stereo positioning methods, ground control points (GCP) are required to eliminate errors. In this study, a method is proposed to improve the stereo positioning accuracy without GCP. First, the factors influencing the Gaofen-3 (GF-3) satellite stereo positioning accuracy were analysed. The errors were divided into systematic fixed errors, spatial and temporal variation errors, and random errors. Subsequently, a systematic geometric error compensation model and a stereo adjustment model were constructed, and a method to improve the multiscene and multimode stereo positioning accuracy without GCP was proposed. Finally, the effects of different intersection angles on the accuracy of stereo positioning were compared and analysed, and the optimal intersection angle of the SAR satellite was quantitatively analysed. The effectiveness and accuracy of this method were verified using GF-3 high-resolution image data. The experimental results indicate that the proposed method can improve the SAR satellite stereo positioning accuracy. The plane positioning accuracy improved by 95.1%, and the elevation positioning accuracy improved by 97.9%. In general, the plane and elevation positioning accuracies of the GF-3 satellite were better than 3 m and 2 m, respectively. The stereo-positioning accuracy of the SAR satellite was the best and most stable when the intersection angle was between 40° and 50°. [ABSTRACT FROM AUTHOR]

AbstractThe source region of the Yellow River, as the main flow-producing area, contributes more than 35% of the total flow of the Yellow River. Here, we surveyed the spatial distribution of the bacterial and fungal communities in the 17 sedimental sites of Longyangxia Valley and Donggi Conag Lake within the source region of the Yellow River. The results revealed that bacterial richness and diversity were higher at the lower elevation of Longyangxia Valley (2588 m) than at higher elevation of Donggi Conag Lake (4096 m), while no obvious differences in fungal richness and diversity were observed. The abundance of the bacterial phylum Actinobacteriota increased in Donggi Conag Lake (30.8%) compared to Longyangxia Valley (15.9%) as the elevation increased. Meanwhile, the abundance of the fungal phylum Rozellomycota decreased (17.6–3.0%) as the elevation increased. The redundancy analysis suggested that the structures of the bacterial and fungal communities were influenced by environmental factors including elevation, organic matter content, hydrolyzed nitrogen, total phosphorus, total potassium, and pH. The results highlighted that rather than the fungal community, the bacterial community in sediments exhibited more significant spatial variation in lake wetlands driving by the influence of elevation and physicochemical variables. [ABSTRACT FROM AUTHOR]

Scaling relations of galaxy clusters are a powerful probe of cosmic isotropy in the late Universe. Owing to their strong cosmological dependence, galaxy cluster scaling relations can obtain tight constraints on the spatial variation of cosmological parameters, such as the Hubble constant (H0), and detect large-scale bulk flow motions. Such tests are crucial to scrutinise the validity of Λ CDM in the local Universe and determine at what cosmic scales (if any) extra-galactic objects converge to isotropy within the cosmic microwave background rest frame. This review describes the methodology for conducting cosmic isotropy tests with cluster scaling relations and examines possible systematic biases. We also discuss the results of past studies that reported statistically significant observed anisotropies in the local Universe. Finally, we explore the future potential of cluster scaling relations as a cosmic isotropy probe given the large amount of multi-wavelength cluster data expected in the near future. This article is part of the discussion meeting issue 'Challenging the standard cosmological model'. [ABSTRACT FROM AUTHOR]

The study investigated the spatial variation of potential methane (CH4) oxidation and residual carbon dioxide (CO2) sequestration in biogeochemical cover (BGCC) system designed to remove CH4, CO2, and hydrogen sulfide (H2S) from landfill gas (LFG) emissions. A 50 cm x 50 cm x 100 cm tank simulated BGCC system, comprising a biochar-amended soil (BAS) layer for CH4 oxidation, a basic oxygen furnace (BOF) slag layer for CO2 and H2S sequestration, and an upper topsoil layer. Synthetic LFG was flushed through the system in five phases, with each corresponding to different compositions and flow rates. Following monitoring, the system was dismantled, and samples were extracted from different depths and locations to analyze spatial variations, focusing on moisture content (MC), organic content (OC), pH, and electrical conductivity (EC). Additionally, batch tests on selected samples from BAS and BOF slag layers were performed to assess potential CH4 oxidation and residual carbonation capacity. The aim of study was to evaluate the BGCC's effectiveness in LFG mitigation, however this study focused on assessing spatial variations in physico-chemical properties, CH4 oxidation in the BAS layer, and residual carbonation in the BOF slag layer. Findings revealed CH4 oxidation in the BAS layer varied between 22.4 and 277.9 µg CH4/g-day, with higher rates in the upper part, and significant spatial variations at 50 cm below ground surface (bgs) compared to 85 cm bgs. The BOF slag layer showed a residual carbonation capacity of 40-49.3 g CO2/kg slag, indicating non-uniform carbonation. Overall, CH4 oxidation and CO2 sequestration capacities varied spatially and with depth in the BGCC system. [ABSTRACT FROM AUTHOR]

Continuous time-series of land cover is critical for attributing runoff, sediment and carbon changes on the Chinese Loess Plateau (CLP). However, current land cover products with annal temporal resolution lack spatial identification accuracy, particularly in capturing authentic changes of cropland, forest and grassland. To address these issues, a 30 m annual land cover dataset was proposed by the Yellow River Conservancy Commission (YRCC_LPLC) for the CLP from 1990 to 2022. Different levels of land cover were classified using different combinations of spectral, monthly and annual temporal and topographic features and Random Forest classifier. Compared to other land cover products (45.64%–73.38%), the accuracy of YRCC_LPLC has a better performance with an overall accuracy of 85.16%. The YRCC_LPLC is capable of capturing not only the explicit spatial variation but also the change direction and change time of land cover, especially for the most critical conversion of cropland into forest and grassland induced by implementation of Grain to Green Program on the CLP. [ABSTRACT FROM AUTHOR]

This study examined the seasonal and spatial dynamics of heavy metal contamination in port-adjacent mangrove sediments along the northern coast of the Oman Sea, Iran. Sediment samples were systematically collected at three strategic ports along distance gradients from mangrove forests (0 m, 0–500 m, and 500–1000 m) during pre-monsoon and post-monsoon seasons to assess monsoon-influenced contamination patterns. Concentrations of Pb, Cd, Ni, Cu, and Zn were measured, revealing significant seasonal and spatial variations. Contamination indices such as the Contamination Factor (CF), Pollution Load Index (PLI), and Ecological Risk Index (RI) were calculated. Results indicated low to moderate contamination levels with Cd being the most significant pollutant. Post-monsoon samples showed increased CF values for Ni and Cu, reflecting the influence of monsoonal runoff. Statistical analyses, including Pearson’s correlation, identified potential anthropogenic sources of contamination. The mean effects range-median quotient (M-ERM-Q) and Total Unit Toxic Index (ΣTU) highlighted the ecological risks, particularly due to Cd. The findings underscore the need for ongoing monitoring and mitigation efforts to protect the mangrove ecosystems from heavy metal pollution. [ABSTRACT FROM AUTHOR]

Genomic-assisted breeding has transitioned from theoretical concepts to practical applications in breeding. Genomic selection (GS) predicts genomic breeding values (GEBV) using dense genetic markers. Single-stage models predict GEBVs from phenotypic observations in one step, fully accounting for the entire variance-covariance structure among genotypes, but face computational challenges. Two-stage models, preferred for their simplicity and efficiency, first calculate adjusted genotypic means accounting for spatial variation within each environment, then use these means to predict GEBVs. However, unweighted (UNW) two-stage models assume independent errors among adjusted means, neglecting correlations among estimation errors. Here, we show that fully-efficient two-stage models perform similarly to UNW models for randomized complete block designs but substantially better for augmented designs. Our simulation studies demonstrate the impact of the fully-efficient methodology on prediction accuracy across different implementations and scenarios. Incorporating non-additive effects and augmented designs significantly improved accuracy, emphasizing the synergy between design and model strategy. Consistent performance requires the estimation error covariance to be incorporated into a random effect (Full_R model) rather than into the residuals. Our results suggest that the fully-efficient methodology, particularly the Full_R model, should be more prevalent, especially as GS increases the appeal of sparse designs. We also provide a comprehensive theoretical background and open-source R code, enhancing understanding and facilitating broader adoption of fully-efficient two-stage models in GS. Here, we offer insights into the practical applications of fully-efficient models and their potential to increase genetic gain, demonstrating a 13.80 % improvement after five selection cycles when moving from UNW to Full_R models. [ABSTRACT FROM AUTHOR]

Impoundment construction has resulted in the alternation and loss of fluvial habitats, threatening the persistence of many native fishes. Compounding this threat, non-native species stocked into impoundments often invade interconnected fluvial habitats, where they may negatively affect native species. Black basses (genus Micropterus) are popular sportfishes with divergent ecologies: some taxa are tolerant of impoundments and widely stocked to create fishing opportunities, whereas others are endemic fluvial specialists that are threatened by introgression with non-native congeneric taxa. We investigated whether impoundments facilitate non-native invasion and introgression in two case study systems: Lake Lanier, Georgia, and Lake Tenkiller, Oklahoma. In both case studies, native fluvial taxa inhabited upstream tributaries and a non-native was established within the downstream impoundment. Results from longitudinal surveys of upstream tributaries provided clear evidence that non-natives invaded upstream from impoundments, and in some cases, extensive introgression with native taxa also occurred. Variation in spatial trends of invasion and directionalities of introgression across case studies provided insights into eco-evolutionary drivers. Within the riverscapes studied, proximity to impoundment appeared to influence invasion and introgression dynamics, and in one case, stream size was also influential. Introgression rates also varied markedly across the species pairs studied–from very little introgression to the onset of hybrid swarming–illustrating the importance of underlying eco-evolutionary mechanisms such as habitat alteration, propagule pressure, and reproductive isolation. Our results underscore the need to consider the upstream influences of impoundments, and the non-natives that invade from them, to create more holistic riverscape conservation plans for fluvial fishes, including native black basses. [ABSTRACT FROM AUTHOR]

Global flow path connectivity along faults or fractures depends on the degree of local flow path connectivity within each fault or fracture and is a key control of groundwater flow and solute transport. However, the mechanical controls on spatial variations in local flow path connectivity within individual faults or fractures are poorly understood. Local flow path connectivity is quantifiable by the laboratory-scale flow dimensions (nlab) within individual faults or fractures, with a lower nlab indicating lower local flow path connectivity. Virtual hydraulic tests were performed on modeled individual fractures to derive a relationship between nlab and a mappable indicator, the ductility index (DI), defined by the mean stress, groundwater pressure, and rock tensile strength. The derived relationship was verified with data obtained from in-situ hydraulic tests of natural faults in rocks with low matrix permeability, poor swelling capacity, and few fracture mineral fillings, also incorporating the effect of linkage among faults in the field. The test results demonstrated that local flow path connectivity within faults or fractures can be high (nlab > 1.5) when DI < 2 but is generally low (nlab < 1.5) when DI > 2, depending on the level of effective-normal-stress-dependent (DI-dependent) fracture-normal displacement. This relationship between nlab and DI is valid even when the value of DI is varied, or the faults are sheared. These findings can be used to help map spatial variations in local flow path connectivity within faults or fractures from limited borehole data. [ABSTRACT FROM AUTHOR]

Spatial-temporal variation in environmental conditions is ubiquitous in nature. This variation simultaneously impacts survival, reproduction, and movement of individuals and thereby the rate at which metapopulations grow. Using the tools of stochastic demography, the metapopulation growth rate is decomposed into five components corresponding to temporal, spatial, and spatial-temporal variation in fitness and spatial and spatial-temporal covariation in dispersal and fitness. While temporal variation in fitness always reduces the metapopulation growth rate, all other sources of variation can either increase or reduce the metapopulation growth rate. Increases occur either by reducing the impacts of temporal variation or by generating a positive fitness-density covariance where individuals tend to concentrate in higher-quality patches. For example, positive autocorrelations in spatial-temporal variability in fitness generate this positive fitness-density covariance for less dispersive populations but decrease it for highly dispersive populations (e.g., migratory species). Negative autocorrelations in spatial-temporal variability have the opposite effects. Positive covariances between movement and future fitness, on short or long timescales, increase growth rates. These positive covariances can arise in unexpected ways. For example, the win-stay, lose-shift dispersal strategy in negatively autocorrelated environments can generate positive spatial covariances that exceed negative spatial-temporal covariances. This decomposition of the metapopulation growth rate provides a way to quantify the relative importance of fundamental sources of variation for metapopulation persistence. [ABSTRACT FROM AUTHOR]