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Ecological restoration programmes (ERP) contribute to greening and regulation service improvement. However, whether greening exacerbates the social‐ecosystem trade‐offs in a degraded ecoregion remains unclear. In this study, we chose South China karst, a global hotspot of greening (improvement of vegetation), as a case‐study. First, we analyzed the degree of greening in different ecoregions and the contribution of landscape to greening during 2000–2020. Second, we investigated the relationship between greening and indicators (land use, gross domestic product [GDP], and population distribution) and explored the relationship between regulation and provision over time. The results showed that the degree of greening in different ecoregions was different, although ERP played a positive role in greening. The rapid greening in degraded ecoregion was relevant to net forest expansion (26.79% of the conversion area), while the slow greening in a non‐degraded ecoregion was associated with net built‐up land expansion (25.81% of the conversion area). Forest expansion in a degraded ecoregion increased out‐migration and exacerbated the trade‐off between greening and GDP reduction, regulation and provision. Our study found that weak service supply in degraded ecoregion limited farming income, which forced farmers to migrate for work and abandon slopeland. In conclusion, the combination of retiring land and emigrating for work triggers land functional transformation and aggravates social‐ecosystem trade‐offs, but agroforestry can mitigate these trade‐offs. Despite there are limitations in the quantification of population migration, it still provides new insight for the next stage of ERP. [ABSTRACT FROM AUTHOR]

Moreover, as we make the fixed factors assumption, HT ht reduces to zero and HT ht equals I SB F sb i . By the same logic, we can develop the FAR test for jointly testing I i SB 0 sb and I SB F sb i by examining whether HT ht holds for the hypothesized values of I i SB 0 sb and I SB F sb i . For example, the FAR test on I SB F sb i just examines whether HT ht holds for the hypothesized value of I SB F sb i . [Extracted from the article]

The reliability of tests on the risk premia in linear factor models is threatened by limited sample sizes and weak identification of risk premia frequently encountered in applied work. We, therefore, propose novel tests on the risk premia that are robust to both limited sample sizes and the identification strength of the risk premia as reflected by the quality of the risk factors. These tests are appealing for empirically relevant settings, and lead to confidence sets of risk premia that can substantially differ from conventional ones. To show the latter, we revisit two high-profile empirical applications. [ABSTRACT FROM AUTHOR]

In this study, a new coupling system of biological filter bed and subsurface-flow constructed wetland based on the self-ventilation network was proposed, and the comparative pollutant removal efficiency at low and high influent concentration of the pilot coupling system with different substrates configurations were investigated. The study found that: The comparison system (b) had better removal rates than that of the original system (a), and the removal rate when treating low influent concentration was 74.10%, 94.14%, 73.57% and 69.53%, while in high influent concentration case was 81.30%, 90.28%, 88.57% and 75.36% for CODCr , NH4+ -N, TN and TP, respectively. The removal of the above main water indexes of the comparison system (b) promoted by 11.00%, 11.55%, 2.69% and 8.09% respectively in low influent concentration case and 4.20%, 9.20%, 7.66% and 13.61% respectively in high influent concentration case when comparing to the original system (a), which showed that the optimized configuration of various kinds of substrates was significant and was more beneficial to the degradation and removal of pollutants. The adsorption and interception function of substrates in the constructed wetland was the main way of phosphorus removal. The function of self-ventilation ensured the amount of DO in the coupling system, making the phosphorus removal was less affected comparing to structure of traditional wetland.

Oxygen is vital for the survival, growth, development, and reproduction of organisms. This study investigates the genetic basis of hypoxia tolerance in the silver sillago (Sillago sihama), a species highly valued in aquaculture despite its traditional susceptibility to low oxygen environments. By employing quantitative trait locus (QTL) mapping and single nucleotide polymorphism (SNP) association studies, the study enhances our comprehension of the genetic factors involved in hypoxia tolerance. Six QTLs associated with hypoxia tolerance have been identified, spanning five distinct linkage groups. Enrichment analyses highlighted important biological processes and pathways, particularly those related to potassium ion transport and cytochrome P450-mediated drug metabolism, which play a critical role in responding to hypoxia stress. Seven candidate genes have been identified as relevant to hypoxia tolerance: cyp20a1, mgst3b, kcnh2, cluh, adk, xdh, and slc19a2. Notably, the SNP association analysis has identified 13 SNPs within the mgst3b gene, with five SNPs (g.583 T > C, g.611 A > G, g.629 T > A, g.633 T > A, g.937 A > G) showing a significant association with hypoxia tolerance. This study sheds light on the molecular mechanisms underlying hypoxia tolerance and suggests potential genetic markers that could be used to enhance S. sihama 's ability to withstand hypoxic conditions through selective breeding, providing valuable insights for the improvement of sustainable aquaculture practices. • Six QTLs linked to hypoxia tolerance were pinpointed over five linkage groups. • Identification of seven genes possibly contributing to hypoxia resilience. • Discovery of five significant hypoxia-associated SNPs in the mgst3b gene. [ABSTRACT FROM AUTHOR]

The preparation of efficient and stable catalysts for biomass tar reforming using low-cost solid waste is of great value for achieving green biomass gasification. In this work, new porous Ni-doped zeolite catalysts were formed by an ion exchange method making use of the waste CGFS as the precursor. At a proper NiO loading content, the catalyst (Na@Air-0.2Ni) exhibits a uniform spherical particle-linked porous structure with NaAlSiO 4 as the supporting matrix and NiO particles anchoring on the surface as active sites. The catalytic performance of the catalysts was investigated in toluene reforming experiments to evaluate their potential for biomass tar conversion. Under optimized conditions (720 °C, S/C = 1.5, and N 2 flow 25 mL/min), toluene conversion reached 92 % using Na@Air-0.2Ni as a catalyst, yielding 2500 μmol/min CO and 2800 μmol/min H 2. Continuous steam reforming of toluene formed to FeNi 3 alloy, which in turn strengthens the stability of the catalyst, and a high toluene conversion of 81 % can be achieved in 450 min continuous experiment, indicating the excellent stability of the catalyst. This work has confirmed that coal gasification slag rich in silicon and aluminum has the potential to prepare new zeolite-based catalysts, which is an important exploration for promoting high-value conversion of solid waste. [Display omitted] [ABSTRACT FROM AUTHOR]

It is widely accepted that residual soils (RSs) form very differently from sedimentary soils. While there have been extensive advances regarding sedimentary soil, little is known about the strain stiffness decay in RS. This study considers granite residual soil (GRS) from Taishan in China, where stiffness behaviors are established using in situ and laboratory investigations. Variability in the soil stiffness is due to its current state, including the depth, test method, and strain. This is established via systematic resonant-column and in situ tests. In situ tests include the seismic dilatometer Marchetti test (SDMT) and the self-boring pressuremeter test (SBPT). The degree of weathering of the test soil varies significantly along the depth direction, and the top layer of the soil has a hardening shell due to severe weathering. The laboratory G-γ decay curves of GRS were determined from the resonant column. A comparison of the shear modulus (from SBPT) obtained by different analysis methods gives the shear modulus from nonlinear analyses. An approach is proposed to properly describe the trends in typical in situ G-γ decay curves based on data from the tests. The G-γ curve obtained from the resonant-column test of GRS was compared with the in situ curves. The shear modulus G, as obtained from laboratory tests, is smaller than the curves of the in situ tests, which reflects the processes of sampling, transportation, and preparation of soil specimens. [ABSTRACT FROM AUTHOR]

Distributed widely in structured marine clay, intra- and inter-particle pores significantly influence the physical properties, hydraulic conductivity, and mechanical behavior of such soil. However, the distribution and morphology characteristics of these pores cannot be quantified through particular single method, and instead, a combination of techniques with different measuring ranges is required. This paper focuses on natural marine clay retrieved from Zhanjiang, China (ZJ clay), this being a typically structured clay with cementation bonding. In this study, the methods of scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), and nitrogen gas adsorption (NGA) were applied in combination to (i) analyze the microscopic characteristics of the pores in natural ZJ clay and the factors influencing the evolution of those pores and (ii) establish the relationship between the microstructural characteristics and macroscopic performance (including both physical and mechanical behaviors) of ZJ clay. The test results show that natural ZJ clay is featured by a randomly oriented open-flocculated structure with cementation bonding and the particles within this clay are interconnected by edge-to-face or edge-to-edge contacts, which contributed to the high structural strength and stability. The hysteresis loops in both the extrusion curves from the MIP tests and the desorption isotherms from the NGA tests indicate the existence of ink-bottle pores in ZJ clay. Through the test results of SEM, MIP, and NGA, further qualitative and quantitative analyses of the complete pore size distribution characteristics of marine clay were allowed. This study enhances the comprehension of pore characteristics of natural structured clays from a microscopic perspective. [ABSTRACT FROM AUTHOR]

Objective: Gastric carcinoma is the most common malignant tumour of the human digestive system worldwide. CD44 serves as a marker for several tumour stem cells, including gastric cancer. However, the prognostic value of CD44 and its correlation with immune infiltration in gastric cancer remain unclear. Methods: The relative expression level of CD44 RNA in gastric cancer was analysed in the TCGA and GEPIA2 databases and validated in the GEO database. Differences in CD44 between gastric cancer cell lines and normal cells were detected by real-time PCR, and the HPA database was used to analyse the differential expression of CD44 protein in gastric cancer and normal tissues. The effect of CD44 on the proliferation and migration of gastric cancer cells was detected by CCK8 and transwell assays. UALCAN was used to analyse the relationship between CD44 expression and clinical parameters, and the Kaplan‒Meier Plotter was used to evaluate the prognostic value, including overall survival (OS), progression-free survival (PFS) and post-progression survival (PPS). The CD44 gene and protein interaction network was constructed by using the Linked Omics, GeneMANIA, STRING and DisGeNET databases. GO and KEGG analyses and GSEA of CD44 were performed by using R language. The correlation between CD44 and immune infiltration was explored by using the TIMER, CIBERSORT and GEPIA databases. Results: CD44 is highly expressed in gastric cancer compared with normal tissues. Inhibition of proliferation and migration of gastric cancer cells after CD44 knockdown was observed. The UALCAN database showed that CD44 was independent of sex in gastric cancer but correlated with cancer stage and lymph node metastasis. Kaplan‒Meier Plotter online analysis showed that OS, PFS and PPS were prolonged in the CD44 low-expression group. GO and KEGG analyses and GSEA results showed that CD44 was mainly located in the endoplasmic reticulum and the extracellular matrix containing collagen, which was mainly involved in protein digestion and absorption. TIMER, CIBERSORT and GEPIA showed that CD44 was associated with infiltrating immune cells and thereby affected survival prognosis. Conclusion: CD44 is highly expressed in gastric cancer and is an independent prognostic factor associated with immune invasion, which can be used as a candidate prognostic biomarker to determine the prognosis associated with gastric immune invasion. [ABSTRACT FROM AUTHOR]

Granite residual soil (GRS) is sensitive to variations in humidity and regularly experiences wetting–drying (D-W) cycles in naturally seasonal climates. It is therefore necessary to explore the effects of D-W cycles on the basic properties of GRS for both engineering safety and scientific research. Triaxial shear tests, computed tomography, nuclear magnetic resonance, and scanning electron microscopy were performed to study the mechanical behavior and structural damage of GRS samples from 0 to 8 D-W cycles. The failure stress, cohesion, and internal friction angle of the GRS samples decreased to different extents with an increase in the number of D-W cycles. The cohesion and internal friction angle of the GRS decreased from 55.95 to 26.93 kPa and 23.28° to 22.65° after eight D-W cycles. Based on computed tomography, the development of mesoscopic cracks can be divided into a crack-generating stage (0–1 D-W cycles), a crack-propagating stage (2–5 D-W cycles), and a crack-stable stage (> 5 D-W cycles). Pore volume distribution curves showed that the pores could be classified into three types (micropores, mesopores, and macropores). The proportion of micropores and mesopores decreased with an increase in the number of D-W cycles, whereas the proportions of macropores and fractures increased. The microstructure in clay particles gradually disintegrated and the pores increased in size and formed connected fractures. The deterioration in the macroscopic mechanical properties of the GRS is the external manifestation of irreversible damage to its microscopic and mesoscopic structure due to the effects of D-W cycles. [ABSTRACT FROM AUTHOR]

Because of the special layered structure and catalytic properties, delafossite CuCrO2 has been extensively studied and can obtain outstanding performance by noble metal coupling. In this work, the Ag-decorated CuCrO2 hybridizations have been elaborated by a thermal evaporation method. Surface morphology characterization and chemical state analysis were combined to indicate that the isolated island distribution of Ag nanoclusters and the generation of a divalent copper ion may result in an improvement in the gas response toward 100 ppm volatile organic compounds, such as formaldehyde (38.7%), methanol (56.8%), and acetone (76.3%). First-principle calculations were carried out to demonstrate the sensing mechanism of the Ag-decorated CuCrO2, where the remarkable change in geometry and electronic structure provided the active interface and noble metal catalysis effect promoting the target gas adsorption and reaction process. Therefore, in this work, we propose that the thermal evaporation can be utilized to act as a controllable modification method to construct nanostructure gas sensors, and the fundamental enhancement mechanism is useful to guide the design of efficient delafossite-based composite catalysts. [ABSTRACT FROM AUTHOR]

As indicated by the theory of a clay-water-electrolyte system, the dispersive mechanism of cohesive soil involves three aspects: low clay content, high sodium ion percentage, and strongly alkaline pH. Accordingly, an empirical equation was established with an associated procedure and criteria proposed for evaluating the dispersivity of cohesive soil. The equation consists of four soil physical and chemical indicators: liquid limit ([W.sub.L]), clay content ([P.sub.C]), sodium percentage in the pore water ([P.sub.S]), and pH. The equation is F = 4 - 0.01(2[W.sub.L] + [P.sub.C] - [P.sub.S]) + 0.1 pH, where F is the soil dispersivity value. Compared with the evaluation based on laboratory tests, the empirical equation had higher accuracy for the evaluation of the dispersivity of cohesive soil, and was thus conducive to greater engineering safety. This indicates that the proposed empirical equation is applicable for evaluating the dispersivity of cohesive soil in general engineering. Key words: dispersive soil, dispersive mechanism, experimental evaluation, empirical equation. Tel qu'indique par la theorie du systeme argile-eau-electrolyte, le mecanisme de dispersion d'un sol cohesif implique trois aspects; un faible contenu en argile, un pourcentage eleve d'ions de sodium, et un fort pH alcalin. Ainsi, une equation empirique a ete etablie, avec une procedure associee et des criteres proposes, pour revaluation de la dispersivite d'un sol cohesif. L'equation comprend quatre indicateurs physiques et chimiques du sol; soit la limite liquide ([W.sub.L]), le contenu en argile ([P.sub.C]), le pourcentage de sodium dans l'eau interstitielle ([P.sub.S]), et le pH. L'equation est F = 4 - 0,01(2[W.sub.L] + [P.sub.C] - [P.sub.S]) + 0,1 pH, ou F est la valeur de dispersivite du sol. Lorsque comparee a revaluation basee sur des essais en laboratoire, l'equation empirique a une meilleure exactitude pour revaluation de la dispersivite des sols cohesifs et entrame donc une securite d'ingenierie plus elevee. Ceci indique que l'equation empirique proposee est applicable pour revaluation de la dispersivite de sols cohesifs dans l'ingenierie generale. [Traduit par la Redaction] Mots-cles: sol dispersif, mecanisme de dispersion, evaluation experimentale, equation empirique., Introduction Dispersive soil is a problematic soil type that has caused increasing concern in geotechnical engineering in recent years (Sherard et al. 1977; Hong and Sheng 1984; Lashkaripour et al. [...]