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The weak bonding of A atoms with MX layers in MAX phases not only enables the selective etching of A layers for MXene preparation but brings about the chance to construct A derivatives/MXene composites via in situ conversion. Here, a facile and general gas‐solid reaction systems are elegantly devised to construct multi‐dimensional MXene based composites including AlF3 nanorods/MXene, AlF3 nanocrystals/MXene, amorphous AlF3/MXene, A filled carbon nanotubes/MXene, layered metal chalcogenides/MXene, MOF/MXene, and so on. The intrinsic effect mechanism of interlayer confinement towards crystal growth, catalytic behavior, van der Waals‐heterostructure construction and coordination reaction are rationally put forward. The tight interface combination and synergistic effect from distinct components make them promising active materials for electrochemical applications. More particularly, the AlF3 nanorods/Nb2C MXene demonstrate bi‐directional catalytic activity toward the conversion between Li2S and lithium polysulfides, which alleviates the shuttle effect in lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]

The soil composition in the Yellow River Subaquatic Delta is complex, and soil liquefaction is a serious threat to the safety of offshore projects. Two-dimensional soil liquefaction evaluation cannot meet the practical needs of engineering. In this paper, in-situ cone penetration tests (CPT) were used to investigate the classification and distribution of soils. Liquefaction variability prediction analysis was performed for the region by the inverse distance weighting (IDW) and full-cokriging methods using the liquefaction vulnerability index (LVI) and cone tip resistance as sample parameters. The results show that: (1) the overall soil grain size in the offshore direction is coarser than that in the far shore, with the clay content less than 18% at Station S1 in the near shore, but more than 90% at Stations S10 and S5 in the far shore; (2) using IDW to predict the liquefaction potential, which first decreases and then increases in the offshore direction, the one-dimensional reconsolidation settlement (SV1D) predicts better than the other two LVIs; (3) a full-cokriging method with normalized cone tip resistance as the main variable and sleeve resistance (fs) as the auxiliary variable is proposed, and its prediction accuracy is better than that of the ordinary kriging (OK) method. [ABSTRACT FROM AUTHOR]

This paper aims to provide a design basis for engineering disaster prevention and mitigation by accurately describing the spatial distribution of soil liquefaction. A group of in-situ Cone Penetration Tests (CPT) was conducted to evaluate the seabed soil properties and liquefaction potential of the Yellow River Subaquatic Delta. The factor of safety against liquefaction (FSL) and liquefaction potential index (LPI) were utilized to investigate the liquefaction characteristics of seabed soils. The findings are as follows: (1) The delta is "near coarse and far fine," with sand and silt dominating the onshore direction and silt and silty clay dominating the offshore direction; (2) Silt, as a structured soil, has a maximum sensitivity of 10, and there are local liquefaction phenomena. The size of a Soil behavior type index can be used as the limit value of liquefaction discrimination in the region; (3) The FSL of the shallow layer is smaller, while that of the deep layer is generally larger. The FSL near the coast is smaller than that far from the coast, but its variation range is large, indicating that the shallow soil layer near the coast is more prone to liquefaction; (4) The LPI of the delta is less than 5, which is significantly affected by the wave cycle loads and geographical environment. Liquefaction can occur, but the probability of large-scale liquefaction is low. [ABSTRACT FROM AUTHOR]

Rosa persica is considered a clonal plant because it is mainly propagated by clonal growth. Due to environmental degradation and habitat devastation, R. persica has been listed as a national second-class protected plant in China. However, the absence of research on wild populations of R. persica has impeded progress in formulating efficient conservation strategies. In this study, we investigated the clonal dispersal distance of R. persica to accurately determine the genetic diversity and population structure of the wild population in Xinjiang. We suggested that 20 m was the threshold distance with which to distinguish between different genets of plants. Based on this, we collated sequencing data from a total of 70 different genets of plants from 117 test samples. Eight populations of R. persica were primarily categorized into three subgroups: BL (Bole), TC (Tacheng) and CG (Changji). Of these, the CG subgroup exhibited the most genetic diversity. This research is the first to illustrates the clonal dispersal distance of R. persica , thus providing valuable reference guidelines for understanding the reproductive characteristics of clonal plants. In addition, the genetic diversity of R. persica provides a theoretical foundation for the formulation of conservation policies. [ABSTRACT FROM AUTHOR]

The Yellow River Delta is one of the most abundant offshore energy areas in China, and the construction of offshore projects is rapidly developing. In this paper, four typical regions of the Yellow River Delta in different periods were selected as research objects. In-situ cone penetration tests (CPTs), geotechnical testing, electron microscope scanning testing, and soil type indexing (Ic) was used to classify and identify the soil layers. At the same time, a modified calculation model based on CPT for the shear wave velocity of fine-grained seabed soil was sought and verified with the measured values. The results showed that: (1) the obtained soil layers are mainly classified by clay and silty soil, which is in line with the conclusions of previous scholars on the classification of the Yellow River Delta soil layer. (2) The measured shear wave velocity is generally between 100 m/s and 250 m/s, and it gradually increases with depth. (3) The depth, cone resistance, and soil behavior index are directly related to the calculation of the shear wave velocity in this area. (4) Discrete analysis of measured and calculated shear wave velocity provides theoretical support for the change of shear wave velocity under different conditions. [ABSTRACT FROM AUTHOR]

The classification of seabed soil in the Yellow River Subaquatic Delta can be obtained more accurately by cone penetration test (CPT). The Soil behavior type index (Ic), over-consolidation ratio (OCR), sensitivity (St) and the relationship between them were clarified. The cyclic stress ratio (CSR) of seabed soil in the Yellow River Delta was calculated based on the wave elements in the 5-year recurrence period, and the cyclic resistance ratio (CRR) was further obtained by calculating the shear wave velocity. The liquefaction analysis was carried out. The analysis of the structure and liquefaction of the seabed soil in the Yellow River Delta is mainly from the following aspects: the seabed soil in the Yellow River Delta is mainly composed of silty soil, sandy soil and cohesive soil. Most areas are in the state of over-consolidation, with the OCR between 20 and 60, and the over-consolidation ratio decreases with the increase of offshore distance. It belongs to the highly sensitive soil layer with poor structure, and the sensitivity is linearly correlated with the over-consolidation ratio. The degree of liquefaction of soil layer is higher than that of offshore soil layer, and the liquefaction of sensitive fine-grained soil layer occurs easily. [ABSTRACT FROM AUTHOR]

Based on the soil behavior type (SBT) and its parameters (Ic) obtained by cone penetration tests (CPTs) in the Yellow River Delta, the standardized shear wave velocity (Vs1), permeability coefficient (k), and fine-grained soil content (FC) were calculated. The fine-grained soil content offshore is higher than that near the coast. The shear wave velocity is primarily distributed in the range of 50 m/s–400 m/s; however, it is lower than that in the nearshore position. The measured regional permeability coefficients are all less than 2 × 10−5 m/s; however, a small area of the nearshore has an increased value, for which the maximum value is approximately 6 × 10−5 m/s. According to the known marine disaster geological distribution map, there are significant differences in the composition of the shear wave velocity and fine-grained soil content between the disturbed delta front and the flat delta front: the fine-grained soil content in the disturbed delta front is less than that in the smooth delta front, and the shear wave velocity in the disturbed delta front is higher than that in the smooth delta front. Moreover, the measured parameters in the disturbed delta area near the shore clearly vary, and hard sand is distributed locally. [ABSTRACT FROM AUTHOR]

The photosynthetic characteristics of three excellent fig cultivars introduced, Branswick, Qingpi and Xinjiang Zaohuang, were compared in the paper, in order to provide reference for the cultivation and breeding of different fig cultivars in Tibet. The daily variation of photosynthetic parameters of the three excellent fig cultivars, Branswick, Qingpi and Xinjiang Zaohuang, which were introduced and cultivated by XiZang Agriculture and Animal Husbandry College in Bayi District, Nyingchi City, Tibet, were measured and compared. The results showed that the net photosynthetic rates (Pn) of three fig cultivars were Qingpi > Branswick > Xinjiang Zaohuang, and the daily variation curves of net photosynthetic rate were all of unimodal pattern. The daily variation curves of transpiration rate (Tr), water utilization efficiency (WUE) and efficiency for solar energy utilization (Pn/Par) of different fig cultivars showed unimodal pattern; the daily variation curve of intercellular CO2 content (Ci) showed decline pattern; the daily variation curve of stomatal conductance (Gs) showed bimodal pattern; Pn had extremely positive correlation with Tr, WUE, Gs, Par, Pn/Par and Ta. [ABSTRACT FROM AUTHOR]

The rising of MXenes not only enriches the two‐dimensional material family but also brings more opportunities for diverse functional applications. However, the controllable synthesis of MXenes is still unsatisfied via the common liquid‐solid etching route, considering the unsolved problems like safety risk, time cost and easy oxidation. Herein, a facile yet efficient gas‐solid (G‐S) reaction methodology is devised by using hydrogen fluoride gas derived from fluorinated organics as the MAX etchant toward high‐efficiency fabrication of multiple MXenes and their derivatives. The innovative G‐S reaction strategy exhibits superb versatility to achieve different gram‐level MXenes (V2C, Ti3C2, Nb2C, Ti2N, Ti3CN, (Mo2/3Y1/3)2C) in a very short time, and even realizes in situ heteroatom doping or synchronous phase conversion of MXenes directly from MAX phases. The obtained MXenes and their derivatives exhibit excellent structure stability and high electron/ion conductivity, making them promising materials for electrochemical applications. In particular, the N‐doped V2C MXene shows superior adsorption and catalytic activity toward lithium polysulfides for advanced lithium sulfur batteries. [ABSTRACT FROM AUTHOR]

The weak bonding of A atoms with MX layers in MAX phases not only enables the selective etching of A layers for MXene preparation but brings about the chance to construct A derivatives/MXene composites via in situ conversion. Here, a facile and general gas-solid reaction systems are elegantly devised to construct multi-dimensional MXene based composites including AlF 3 nanorods/MXene, AlF 3 nanocrystals/MXene, amorphous AlF 3 /MXene, A filled carbon nanotubes/MXene, layered metal chalcogenides/MXene, MOF/MXene, and so on. The intrinsic effect mechanism of interlayer confinement towards crystal growth, catalytic behavior, van der Waals-heterostructure construction and coordination reaction are rationally put forward. The tight interface combination and synergistic effect from distinct components make them promising active materials for electrochemical applications. More particularly, the AlF 3 nanorods/Nb 2 C MXene demonstrate bi-directional catalytic activity toward the conversion between Li 2 S and lithium polysulfides, which alleviates the shuttle effect in lithium-sulfur batteries., (© 2024 Wiley-VCH GmbH.)

Objective: Insulin-like growth factor-binding protein-3 (IGFBP3) is the major protein that binds with insulin-like growth factor-1 (IGF-1) and is considered to be involved in the development and progression of various cancers. We aimed to examine the association between prostate cancer (PCa) and the IGFBP3 gene-202A/C polymorphism., Methods: A comprehensive search within PubMed, EMBASE, and Cochrane Library was conducted to identify all case-control studies up to October 30, 2015, for a meta-analysis. Pooled odds ratios (ORs) and the 95% confidence intervals (CIs) were calculated using the fixed or random effects model., Results: Eighteen studies including 10,538 cases and 10,078 controls were identified. Overall, the CC genotype of IGFBP3-202A/C polymorphism was associated with increased risk of PCa in homozygote comparison (CC vs AA - OR =1.16, 95% CI: 1.08-1.25) and in recessive model (CC vs AA+AC - OR =1.11, 95% CI: 1.04-1.17). In dominant model, the CC/AC genotypes also implicated an increased risk of PCa (CC+AC vs AA - OR =1.11, 95% CI: 1.05-1.19). The C allele of IGFBP3-202A/C polymorphism was the risk allele for PCa relative to the A allele (OR =1.09, 95% CI: 1.05-1.14). Further stratification analysis revealed that the association between -202A/C polymorphism and PCa risk among Caucasians, but not in other ethnicities, was statistically significant (recessive model, OR =1.10, 95% CI: 1.02-1.19). In addition, the IGFBP3-202A/C polymorphism was associated with PCa risk in both population-based and hospital-based studies in homozygote comparison, recessive model, and allele model., Conclusion: Our meta-analysis indicates that the IGFBP3-202A/C polymorphism is associated with the risk of PCa, particularly in Caucasians, with the C allele being the risk allele for PCa.