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Afforestation has a substantial influence on soil fungal communities by introducing ecological variations within forest ecosystems via the inclusion of distinct tree species (coniferous and broadleaf) and afforestation patterns (pure forests and mixed forests). However, the specific effects of these variations on soil fungal communities require further investigation. Soil samples from birch (B: Betula platyphylla Suk.), larch (L: Larix gmelinii (Rupr.) Kuzen.), and mixed birch and larch (B–L) forests were used in this study, and a shrub–grassland field (S–G) was used as a reference. The abundance, diversity, and community composition of fungi in the soil of the monoculture forest (B and L), mixed forest (B–L), and S–G were studied by high‐throughput sequencing. The results showed that Basidiomycota was the dominant fungus in B and B–L, and the dominant genera were Inocybe and Amanita, respectively. Ascomycota was the dominant fungus in L and S–G, and the dominant genus was Mortierella. Afforestation reduced the richness and diversity of soil fungi. Larch forests were richer in soil fungi than B and B–L forests. Soil organic carbon was the main soil factor affecting the soil fungal community structure. Soil fungal community network changed less after planting L than after planting B and B–L, and the soil fungal community structure was more complex and stable in L than in B and B–L. For soil fungal community composition and function, mixed forests did not show outstanding advantages. Planting monoculture forests may be a more effective afforestation strategy in the rocky mountain areas of North China. [ABSTRACT FROM AUTHOR]

Given the developmental program outlined in United Nations Sustainable Development Goal 15 (Life on Land) and the to effectively address the challenge of biodiversity decline while mitigating the adverse effects of climate change, particularly drought, on terrestrial forest ecosystems, a fundamental reorientation of global forest restoration paradigms is warranted. It is imperative to move beyond a narrow emphasis on expanding forest area and instead prioritize the enhancement of biodiversity and functional attributes within these ecosystems. However, the differential response mechanisms of forest ecosystem functional communities and main plant functional types (PFTs) to environmental factors, especially soil and topography, remains unclear, especially at plant level. Here, we divided the functional communities of 93 sites in the study area into seven groups through Two‐way indicator species analysis (TWINSPAN), and studied the different functional communities, namely dynamic succession, species richness, and PFT compositional differences. We also analyzed the various PFTs and functional community response mechanisms to soil and topographic factors using canonical correspondence analysis (CCA). The main results were as follows: (1) With the successional stages of PFTs, vegetation diversity across multiple functional communities inceased, tree and shrub proportions and importance increased, while herbs decreased. (2) From the arid and barren areas (i.e., G2), to the humid and fertile areas (i.e., G6 and G7), various compositional PFT differences, and their responses to soil and topographic factors, were found, namely, xerophytic, annual and biennial species gradually changed to mesophytic, hygrophytic, and perennial species (richness increased 6.94 ~ 27.33%, important value (IV) increased 8.73 ~ 29.45%) for shrubs and herbs. (3) Functional communities in various successional stages display distinct sensitivities to soil and topographic factors, as evidenced by a notable increase in the richness and IV of deciduous broad‐leaved tree species, rendering their communities more responsive to SOC and AS, whereas evergreen coniferous trees (e.g., Pinus tabuliformis Carr.) were sensitive to altitude (AL) and exhibited a tendency to transition from plantations to natural secondary forests predominantly at higher altitudes (above 1200 m). Our findings suggest that site conditions influence scenarios, and that different PFT responses and adjustments to soil and topography factors affect whole functional community dynamic succession processes, which can profoundly impact forest ecosystem function predictions based on PFT changes in the Loess Plateau of China. [ABSTRACT FROM AUTHOR]

Summary An innovative hybrid coupled wall system consists of reinforced concrete (RC) wall piers connected with replaceable steel coupling beams (RSCBs) throughout their height. The RSCBs are designed with a central "fuse" shear link connected to steel beam segments at both ends, which are capacity designed to remain elastic. During a damaging earthquake, the fuse shear links yield and dissipate seismic energy, and once damaged, they can be easily replaced due to specialized link‐to‐beam connection details. Therefore, this system is expected to provide enhanced seismic performance over a conventional RC coupled wall system, particularly in terms of repair costs and time after damaging earthquakes. This paper presents an overview of seismic design considerations of this new system, which is intended as a guide for design practitioners to adopt the system. Design procedure of this system is first summarized, followed by description of the coupling ratio selection, member sizing, connection detailing, and modeling recommendations of the system. Furthermore, an analytical case study for a high‐rise building is presented to highlight the benefit of using this system for enhancement to overall building performance. In the end, this paper presents a few real‐world applications of RSCBs in super‐tall buildings in China. [ABSTRACT FROM AUTHOR]

This paper presents seismic retrofit for the single-story brick-wood structure representative of existing rural buildings in Beijing. The retrofitting effectiveness was examined through large-scale shaking table tests on the unretrofitted and retrofitted specimens. The test results indicate that, for the unretrofitted specimen, the front brick columns deform and damage severely when subjected to the longitudinal motions, because large of lateral stiffnesses difference exists between the front and back longitudinal walls. The brick gables experience significant out-of-plane deformation, resulting in diagonal cracks. The unretrofitted specimen is cracked under minor earthquakes, significantly damaged under design basis earthquakes, and approaches to collapse under rare earthquakes. The method of seismic retrofit was proposed based on the test results of the unretrofitted specimen, including the addition of a steel doorframe, steel window frames and steel plate collar beams, and the strengthening of the brick gables and columns by cement mortar reinforced with steel mesh. Shaking table test results show that the retrofit method significantly improves the earthquake-resistant capacity of the brick-wood building structure, and the retrofitted specimen can achieve the design objective of 'operational under minor earthquakes, repairable damage under design basis earthquakes, and collapse prevention under rare earthquakes'. [ABSTRACT FROM AUTHOR]

• High-spatial resolution mapping for the distribution of air density in China. • Identification of the characteristics of air density on the scale of elevation. • The influence of air density on energy production is quantified. • Mean energy production reduction at 1000 m above ground level is 6.6%. The distribution characteristics of air density in China were modelled on a high-spatial-resolution scale (4000 m × 4000 m) and the absolute error was calculated by comparing with constant air density. Daily mean air pressure and air temperature time series from 2403 meteorological stations for the period 1998–2018 were used to compute air density at the hub height of a typical wind turbine. The statistical air density distributions were applied in the study area and the influence of elevation on changes in air density was quantified. Mean annual energy production in the study area was estimated using extrapolated parameters of the Weibull distribution and adjusted power curves. Compared with energy production under the assumption of constant air density, the results demonstrate that over 33% of the study area had a mean air density less than 1.000 kg/m3 due to the effect of elevation. Values as low as 0.347 kg/m3 were observed in the Tibetan Plateau. Energy production was underestimated (0.04–1.76%) in the north-east and north when the variability of air density was considered, and wind resources were overestimated by more than 20% in approximately 13.1% of the study area. The results of this study will contribute to identifying suitable locations for developing the wind energy industry. The influence of air density on wind energy production at different elevations can now be quantified, allowing more efficient utilization of wind resources. [ABSTRACT FROM AUTHOR]

To assess the impact of air density on future wind resources under representative concentration pathway (RCP) scenarios (RCP2.6, RCP4.5, and RCP8.5), the Coordinated Regional Downscaling Experiment-East Asia project was utilized to simulate the future air density characteristics of China (2021–2100). Empirical air density distributions were calculated, and fourteen probability density functions were fitted to the empirical air density distributions, determining the optimal fitted distribution functions. In this study, the effect of air density on the annual energy production and wind power density was quantified. The results indicated that only approximately 4 % of regional air density values reaches the standard air density under the three climate scenarios. The seven parameter Generalized Extreme Value-Generalized Extreme Value distribution, six parameter Gamma-Generalized Extreme Value distribution, and six parameter Exponentiated Weibull- Generalized Extreme Value distribution matched the empirical distributions well under RCP2.6, RCP4.5, and RCP8.5, respectively. Annual energy production and wind power density decreased by more than 15 % after considering air density. Under the different RCP scenarios (RCP2.6, RCP4.5, and RCP8.5), the errors of annual energy production and wind power density gradually escalate. In the Tibetan Plateau region, accounting for air density results in an overestimation of annual energy production by over 40 % and wind power density by more than 35 %. The findings of this study offer guidance for future wind energy resource planning, enabling optimal utilization of wind energy resources. [Display omitted] • Evaluating future air density in spatial distribution under diverse RCP scenarios. • CORDEX-EA is utilized for mapping air density variations in China. • The impact of the air density on the future wind energy potential is assessed. • Wind energy overestimation exceeds 20 % in over 30 % of the study areas under RCP2.6 [ABSTRACT FROM AUTHOR]

This study proposes a deep neural network-based wind energy assessment method, aiming to systematically evaluate the effects of the spatiotemporal variations in air density on wind energy assessment in China. On this basis, the spatiotemporal patterns of air density are modelled on a high-spatial-resolution scale (1000 m × 1000 m). The influence of the spatiotemporal distribution characteristics of air density on the wind energy production is quantified, and the spatiotemporal variability of the corresponding wind energy production is estimated. The results demonstrate that changes in air density during the year present typical periodic characteristics. The mean air density value in January is 1.079 kg/m3, the highest throughout the year. The difference in mean air density between cold and warm seasons in the study area shows a decreasing law of higher in the northeast and lower in the southwest. When the elevation is less than 3500 m, it reaches 5.06%. The observed spatiotemporal variability in annual energy production exhibits a distinct seasonal cycle, with the highest production appears in spring (2.968 GWh/yr). The total annual energy production in the cold season is 16.08 GWh/yr, whereas the annual energy production decreases by higher than 23.46% when it comes to the warm season. • A new wind energy assessment method based on deep neural network was developed. • High-spatial resolution mapping for the spatiotemporal distribution of air density. • Changes in air density during the year present typical periodic characteristics. • The influence of variations in air density on energy production is quantified. • Assessment of variability in energy production at different spatiotemporal scales. [ABSTRACT FROM AUTHOR]

[Display omitted] • SOC content of shrubland is closely related to elevation and total nitrogen. • Elevation affects shrubland SOC content through both direct and indirect pathways. • Total nitrogen has the greatest total and direct effect on the shrubland SOC content. Shrubland has been identified as the most uncertain factor in the C sink in China, but little detail is available regarding the soil organic carbon (SOC) of this significant biome. The effects of influencing factors on the spatial distribution of SOC content have been extensively investigated, but whether these factors reflect a 'direct' or 'indirect' effect is not clear. In this study, 93 topsoil plots were surveyed to measure the SOC content and the influencing factors, including topography (elevation (Ele), slope gradient (SG), and aspect (SA)), soil conditions (pH, bulk density (BD), soil total porosity (STP), soil water content (SWC), soil temperature (ST), soil salinity (SS), total nitrogen (TN), total phosphorus (TP), and available potassium (AK)), and vegetation (aboveground biomass (AGB)) on the Bashang Plateau in China. The results indicated that the SOC content varied moderately across the entire catchment and was closely related to Ele and all soil conditions (P < 0.05), except for STP. All influencing factors were grouped into four driving indicators of the spatial distribution of SOC content: soil nutrients (TN, TP, and AK), migration of soil water and salt (pH, SWC, and SS), topography and biomass (Ele, SG, and AGB), and basic soil physical properties (BD, STP, and ST). Soil nutrients had the largest relative contribution to the spatial distribution of the SOC content. Ele influenced the spatial distribution of SOC content through direct and indirect effects, and TN had the greatest effect on the SOC content. Ele and TN were the critical factors controlling the spatial distribution of SOC content in the shrubland on the Bashang Plateau, China. The results of this study are a useful supplement to the study of SOC in shrublands and may provide support for the evaluation of the shrubland SOC dynamics after regional vegetation restoration in China and globally. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new joint probability density function of air density and wind speed was developed. • Integration of the air density distribution into statistical wind resource models. • Introduction to Weibull–Gamma distribution for fitting air density distributions. • Modelling of bivariate air density and wind speed distributions with Gumbel copulas. • Mean annual energy production is higher than 7.00 GWh/yr for 4.62% of the study area. This paper proposes a joint probability density function of air density and wind speed, aiming to integrate the air density distribution into statistical wind resource models, thereby helping better understand the correlation between air density and wind speed at different spatiotemporal scales. Hourly air pressure, temperature, and wind speed time series data from 1745 meteorological stations distributed over China for the period 2008–2019 were used to calculate the empirical distributions of air density and wind speed. Four one-component probability density functions and ten two-component mixture probability density functions were fitted to the empirical distributions. It is indicated that the five-parameter Weibull–Gamma distribution is able to achieves more accurate and stable effects in both unimodal and bimodal air density empirical distribution, and the six-parameter Weibull–Burr distribution is the most appropriate distribution for describing wind speed regimes. The parameterised air density and wind speed marginal distributions were linked using five joint copulas. The goodness-of-fit evaluation of the copula models demonstrates that the Gumbel copula most accurately reproduces the bivariate empirical distribution of air density and wind speed. The application of joint distribution has the capability to simplify the evaluation procedures for wind resource assessment while significantly increasing the accuracy of the evaluation results, and also achieve a systematic assessment of available wind resources, considering the temporal patterns of air density. The results of this study will contribute to offering critical information for making better decisions on wind energy projects to realise full development and effective utilisation of wind resources. [ABSTRACT FROM AUTHOR]

Introduction: To analyze the influencing factors for progression from newly diagnosed prediabetes (PreDM) to diabetes within 3 years and establish a prediction model to assess the 3-year risk of developing diabetes in patients with PreDM., Methods: Subjects who were diagnosed with new-onset PreDM at the Physical Examination Center of the First Affiliated Hospital of Soochow University from October 1, 2015 to May 31, 2023 and completed the 3-year follow-up were selected as the study population. Data on gender, age, body mass index (BMI), waist circumference, etc. were collected. After 3 years of follow-up, subjects were divided into a diabetes group and a non-diabetes group. Baseline data between the two groups were compared. A prediction model based on logistic regression was established with nomogram drawn. The calibration was also depicted., Results: Comparison between diabetes group and non-diabetes group: Differences in 24 indicators including gender, age, history of hypertension, fatty liver, BMI, waist circumference, systolic blood pressure, diastolic blood pressure, fasting blood glucose, HbA1c, etc. were statistically significant between the two groups (P<0.05). Differences in smoking, creatinine and platelet count were not statistically significant between the two groups (P>0.05). Logistic regression analysis showed that ageing, elevated BMI, male gender, high fasting blood glucose, increased LDL-C, fatty liver, liver dysfunction were risk factors for progression from PreDM to diabetes within 3 years (P<0.05), while HDL-C was a protective factor (P<0.05). The derived formula was: In(p/1-p)=0.181×age (40-54 years old)/0.973×age (55-74 years old)/1.868×age (≥75 years old)-0.192×gender (male)+0.151×blood glucose-0.538×BMI (24-28)-0.538×BMI (≥28)-0.109×HDL-C+0.021×LDL-C+0.365×fatty liver (yes)+0.444×liver dysfunction (yes)-10.038. The AUC of the model for predicting progression from PreDM to diabetes within 3 years was 0.787, indicating good predictive ability of the model., Conclusions: The risk prediction model for developing diabetes within 3 years in patients with PreDM constructed based on 8 influencing factors including age, BMI, gender, fasting blood glucose, LDL-C, HDL-C, fatty liver and liver dysfunction showed good discrimination and calibration., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Yang, Liu, Du, Zhu, Lu, Wu, Zhang, Ji and Zheng.)

Vegetation plays a vital role in regulating hydrological cycle and controlling soil erosion at multiple spatial and temporal scales. Establishing shrub-grass community is one of the widely adopted practices to increase rainfall infiltration and reduce soil erosion in water-limited and highland regions. To understand the effects of such vegetation communities on soil erosion and overland flow under different rainfall regimes at the hillslope scale, we conducted rainfall simulation experiments by setting up parallel plots at fixed slope of 15 ° including unvegetated (coverage 0%), shrub only (coverage 50%), grass only (coverage 50%), and shrub-grass covered (coverages 25%, 50%, 75%, and 100%) and constant rainfall intensities of 30, 60, and 90 mm h -1 rainfalls lasting 60 min each after the initiation of overland flow. Two native species Lespedeza bicolor and Carex giraldiana, distributed in the soil sampling region were planted on the plots to achieve designed coverages. We found that the overland flow and sediment load from vegetated slopes were reduced by 9%-58% and 27%-98%, respectively, compared with unvegetated slopes while the infiltration rate increased by over 45%. Shrub-grass community reduced the overland flow and sediment yield more significantly than shrub only and grass only treatments with the same coverage of 50% under three rainfall intensities. In addition, the overland flow rate linearly decreased while the mean sediment yield exponentially reduced against the increase in shrub-grass community coverage. Hydrodynamically, shrub-grass communities not only increased the critical hydrodynamic forces for the initiating soil erosion but also increased the resistance coefficient leading to reduce overland flow velocity, stream power, and thus soil erosion from the vegetative slope even under extreme rainfalls. Our research highlights the importance of developing the shrub-grass communities to reduce the quantity and energy of overland flow and control soil erosion on the hillslopes in water-limited and highland regions., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to investigate the relationship between high intraocular pressure (IOP) and uric acid., Methods: In a retrospective cross-sectional study, 19,147 participants were included in 2018. Serum uric acid (SUA) was cut to four groups as Q1 to Q4, according to the quartiles. The odds ratio (OR) and 95% confidence interval (CI) of different SUA levels were estimated by a binomial logistic regression model in men and women. A restrictive cubic spline method was used to estimate the dose-response relationship between uric acid and high IOP. Subgroup analysis was performed to find the gender-specific association between uric acid and high IOP., Results: In women, after adjusting for confounding factors, the Q3 and Q4 of SUA levels were significantly associated with the risk of high IOP. The OR with 95% CI for Q3 and Q4 were 1.77 (1.22, 2.57) and 1.51 (1.01, 2.26), respectively, Q1 as a reference. For men, SUA levels were not associated with the incidence of high IOP. Moreover, the spline analysis found an inverted U-shaped relationship between uric acid and high IOP in women (P = 0.0171)., Conclusions: Elevated levels of SUAwere independently associated with an increased risk of high IOP in women, but not in men. In addition, uric acid had an inverse U-shaped nonlinear dose-response relationship with high IOP in women.