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The rail transit in sulfate-rich areas faces the combined effects of stray current and salt corrosion; however, the sulfate ion transport and concrete degradation mechanisms under such conditions are still unclear. To address this issue, novel sulfate transport and mesoscale splitting tests were designed, with a focus on considering the differences between the interfacial transition zone (ITZ) and cement matrix. Under the influence of stray current, the ITZ played a pivotal role in regulating the transport and mechanical failure processes of sulfate attack, while the tortuous and blocking effects of aggregates almost disappeared. This phenomenon was termed the “stray current-induced ITZ effect.” The experimental data revealed that the difference in sulfate ion transport attributed to the ITZ ranged from 1.90 to 2.31 times, while the difference in splitting strength ranged from 1.56 to 1.64 times. Through the real-time synchronization of splitting experiments and microsecond-responsive particle image velocimetry (PIV) technology, the mechanical properties were exposed to the consequences of the stray current-induced ITZ effect. The number of splitting cracks in the concrete increased, rather than along the central axis, which was significantly different from the conditions without stray current and the ideal Brazilian disk test. Furthermore, a sulfate ion mass transfer model that incorporates reactivity and electrodiffusion was meticulously constructed. The embedded finite element calculation exhibited excellent agreement with the experimental results, indicating its reliability and accuracy. Additionally, the stress field was determined utilizing analytical methods, and the mechanism underlying crack propagation was successfully obtained. Compared to the cement matrix, a stray current led to more sulfates, more microstructure degradation, and greater increases in thickness and porosity in the ITZ, which was considered to be the essence of the stray current-induced ITZ effect.

Healthy lifestyle might alleviate the socioeconomic inequities in health, but the extent of the joint and interactive effects of these two factors on dementia are unclear. This study aimed to detect the joint and interactive associations of socioeconomic status (SES) and lifestyle factors with incident dementia risk, and the underlying brain imaging alterations. Cox proportional hazards analysis was performed to test the joint and interactive associations. Partial correlation analysis was performed to reflect the brain imaging alterations. A total of 276,730 participants with a mean age of 55.9 (±8.0) years old from UK biobank were included. Over 8.5 (±2.6) years of follow-up, 3013 participants were diagnosed with dementia. Participants with high SES and most healthy lifestyle had a significantly lower risk of incident dementia (HR=0.19, 95% CI=0.14 to 0.26, P<2×10−16), Alzheimer’s disease (AD, HR=0.19, 95% CI=0.13 to 0.29, P=8.94×10−15), and vascular dementia (HR=0.24, 95% CI=0.12 to 0.48, P=7.57×10−05) compared with participants with low SES and an unhealthy lifestyle. Significant interactions were found between SES and lifestyle on dementia (P=0.002) and AD (P=0.001) risks; the association between lifestyle and dementia was stronger among those of high SES. The combination of high SES and healthy lifestyle was positively associated with higher volumes in brain regions vulnerable to dementia-related atrophy. These findings suggest that SES and lifestyle significantly interact and influence dementia with its related brain structure phenotypes.

The purpose of this study is to investigate the changes in the microstructure of 5083-H116 alloys under different annealing temperatures and sensitization treatments. The properties of both annealed and sensitized samples were analyzed using various techniques, including tensile testing, scanning electron microscopy, and optical microscopy. The susceptibility of the alloy to intergranular corrosion (IGC) and stress corrosion cracking (SCC) was evaluated using the nitric acid mass loss test (ASTM G67 NAMLT) and the slow strain rate test, respectively. The results indicate that annealing temperatures below 200 °C and above 300 °C resulted in high susceptibility to IGC and SCC due to the continuous precipitation of β-phase (Mg2Al3) along the grain boundaries. In contrast, annealing in the temperature range of 200–250 °C led to the formation of discontinuous β-phase precipitates at the grain boundaries, resulting in high resistance to IGC and SCC.

C32H44O6, monoclinic, P21(no. 4), a= 12.2561 Å, b= 10.3674(4) Å, c= 23.3835(8) Å, β= 98.463°, V= 2938.85(19) Å3, Z= 2, Rgt(F) = 0.0602, wRref(F2) = 0.1537, T = 273(2) K.

Shield tunneling and post-tunneling steady seepage are accompanied by stress and displacement variations, which could induce and influence the soil arching effect. Although there are many studies on the tunneling-induced soil arching effect, the research about the effect of seepage on soil arching effect is extremely lacking. In this study, a numerical model is firstly established and verified by field data. Then, a series of numerical models, whose simulation method of steady seepage is verified by adopting the conformal mapping technique, are established to study the soil arching evolution of deep-buried tunneling and post-construction steady seepage. The results indicate that seepage leads to an increase in effective vertical stress, which is consistent with the existing theory. The seepage weakens the soil arching effect resulting in the height of the arch zone reducing from 2.38D(Dis the tunnel diameter) to 1.25D. The seepage leads to the further development of ground consolidation settlement, but the differential displacement in the soil mass decreases. The ground reaction curve in the steady seepage condition shows a bigger value than that after excavation. It is reasonable to control the ground loss ratio in the range of 0.5–1.0%, which can minimize overburden pressure with moderate ground deformation.

Single Alter shielded T-200BM3 weighing precipitation gauges are widely used in the measurement of all precipitation types (rainfall, snow and mixed precipitation) in unattended boreal or alpine regions, but their original datasets must be adjusted for undercatch errors caused by wind in snowy, windy and harsh environments. Therefore, previous researchers have developed many adjustment methods for all precipitation types on different time scales. However, which adjustment method is suitable for T-200BM3 weighing gauge wind-induced error adjustment in harsh alpine regions is unclear. Therefore, precipitation measurement intercomparison experiments were conducted in the Qilian Mountains from July 2018 to July 2021, and eight adjustment methods; were evaluated for wind-induced errors for daily, individual precipitation event, hourly, and half-hourly time scales. Z2004 outperformed the other adjustment methods in regard to the daily measurements of snow and mixed precipitation. Regarding individual snowfall events, M2007 reduced the absolute value of RMSE (bias) from 1.44 to 1.32 mm (0.77–0.24 mm) and could be recommended for snowfall event adjustment. K2017-1 attained a better performance than K2017-2 in regard to half-hourly snowfall and mixed sample adjustment and was more suitable for half-hourly snowfall sample adjustment. K2017-1 reduced the absolute value of bias from 0.07 to 0.00 mm for snowfall. Finally, Z2004, M2007, and K2017-1 yielded better adjustment results for the daily accumulation precipitation amount (>2 mm d−1), individual snowfall events (>2 mm per event), and half-hourly accumulation snowfall or mixed samples (>1 mm 30 min−1), respectively. However, further intercomparison in different climate regions is needed for trace precipitation samples.

C22H26O6, orthorhombic, P212121(no. 19), a= 7.6648(5) Å, b= 11.2663(6) Å, c= 22.7321(7) Å, V= 1963.0(2) Å3, Z= 4, Rgt(F) = 0.0652, wRref(F2) = 0.1399, T = 273(2) K.

Groundwater leakage in shield tunnels poses a threat to the safety and durability of tunnel structures. Disturbance of adjacent constructions during the operation of shield tunnels frequently occurs in China, leading to deformation of tunnel lining and leakage in joints. Understanding the impact of adjacent constructions on the waterproofing performance of the lining is critical for the protection of shield tunnels. In this study, the weakening behavior of waterproof performance was investigated in the joints of shield tunnels under transverse deformation induced by adjacent construction. First, the relationship between the joint opening and transverse deformation under three typical adjacent constructions (upper loading, upper excavation, and side excavation) was investigated via elaborate numerical simulations. Subsequently, the evolution of the waterproof performance of a common gasket with a joint opening was examined by establishing a coupled Eulerian–Lagrangian model of joint seepage, and a formula describing the relationship between waterproof performance and joint opening was proposed. Finally, the weakening law of waterproofing performance was investigated based on the results of the aforementioned studies. It was determined that the joints with the greatest decline in waterproof performance were located at the tunnel shoulder in the upper loading case, tunnel crown in the upper excavation case, and tunnel shoulder in the side excavation case. When the waterproof performance of these joints decreased to 50% and 30%, the transverse deformations were 60 and 90 mm under upper loading, 90 and 140 mm under upper excavation, and 45 and 70 mm under side excavation, respectively. The results provide a straightforward reference for setting a controlled deformation standard considering the waterproof performance.

Precipitation data is vital fundamental data for climate change. However, obtaining precise gauge-measured precipitation in high-altitude mountains is challenging, and the precipitation obtained from various gauge types at the same station may vary. To understand the differences in precipitation observations among the three commonly used gauges in China (Chinese Standard Precipitation Gauges (CSPG), Total Rain weighing Sensor (TRwS), and Geonor T-200B (T200B)) in high-altitude mountains and to recommend a stable and cost-effective weighing gauge, a precipitation intercomparison experiment was conducted at Hulu-1 station in the Qilian Mountains. The wind-induced error in measurement was corrected with the ‘universal’ transfer function recommended by the Word Meteorological Organization. The comparison results, adjusted for systematic errors, showed that the rain, snow and mixed precipitation of CSPG and TRwS equipped with the same octagonal vertical double fence shields (CSPGDFand TRwSDF) and single-Alter shields (CSPGsand TRwSs) were close, while the precipitation of Tretyakov-shielded T200B was notably higher than that of CSPGsand TRwSs. The average differences in annual and daily precipitation between CSPGDFand TRwSDFfrom 2017 to 2021 were 12.9 mm and 0.10 mm, respectively. The daily precipitation difference between CSPGsand TRwSsfrom April 2019–December 2021 was 0.10 mm, while the differences between T200Bsand CSPGsand TRwSswas 0.28 mm and 0.38 mm, respectively. The wind shield performance of Alter and Tretyakov was not much different at Hulu-1 site with low wind speed, thus the measurement principle of T200Bswas the primary cause of the high observations. Taking the corrected CSPGDFmeasurement as the standard, the dynamic loss of CSPGswas 17.6%, while that of CSPGUnwas 55.6%, indicating that the single-Alter shield could effectively reduce the impact of wind on precipitation measurement. Considering the comparison results and the price difference of the instruments, it was recommended to use a single-Alter shielded TRwS gauge for precipitation observation in high-altitude mountains.

Objective: Endothelial dysfunction is one candidate for triggering neointima formation after arteriovenous grafts (AVGs), but the factors mediating this process are unclear. The purpose of this study was to investigate the role of endoplasmic reticulum stress (ERS)-induced endothelial dysfunction in neointima formation following AVGs in high-fat diet (HFD) mice. Methods: CCAAT-enhancer-binding protein-homologous protein (CHOP) knockout (KO) mice were created. Mice were fed with HFD to produce HFD model. AVGs model were applied in the groups of WT ND, WT HFD, and CHOP KO HFD. Human umbilical vein endothelial cells (HUVECs) were cultured with oxidized low density lipoprotein (ox-LDL) (40 mg/L) for the indicated time lengths (0, 6, 12, 24 h). ERS inhibitor tauroursodeoxycholic acid (TUDCA) was used to block ERS. Immunohistochemical staining was used to observe the changes of ICAM1. Changes of ERS were detected by real-time RT-PCR. Protein expression levels and ERS activation were detected by Western blotting. Endothellial cell function was determined by endothelial permeability assay and transendothelial migration assay. Results: HFD increased neointima formation in AVGs associated with endothelial dysfunction. At the same time, ERS was increased in endothelial cells (ECs) after AVGs in mice consuming the HFD. In vitro, ox-LDL was found to stimulate ERS, increase the permeability of the EC monolayer, and cause endothelial dysfunction. Blocking ERS with TUDCA or CHOP siRNA reversed the EC dysfunction caused by ox-LDL. In vivo, knockout of CHOP (CHOP KO) protected the function of ECs and decreased neointima formation after AVGs in HFD mice. Conclusion: Inhibiting ERS in ECs could improve the function of AVGs.

The innovative technology of microbially induced calcium carbonate precipitation (MICP) soil modification is widely used in soil reinforcement, soil remediation, environmental remediation and other fields, and has gradually become a hot research direction. Recent research is more focused on the overall physical and mechanical characteristics of the uniform reinforced specimen. There is limited research on the distribution characteristics of calcium carbonate along the seepage path during the reinforcement process. However, the distribution characteristics of calcium carbonate play a significant role in the physical and mechanical characteristics of the solid, especially in the large-scale MICP reinforcement process. In this study, based on the microbial mineralization reaction tests of different concentrations of cement solution at the laboratory sample scale, the calcium carbonate distribution on the surface of the sample at the microscale SEM observation and the CT scanning reconstruction of the micro pore structure characteristics of the microbial reinforced soil, we discussed the characteristics of the non-uniform reduction of calcium carbonate distribution and porosity in the process of microbial consolidation. Based on the Kozeny-Carman equation, the conceptual model of effective porosity was introduced, and the time relationship between porosity and calcium carbonate precipitation was considered to establish a bio-chemical-seepage multi-physics field coupling model. The precipitation of calcium carbonate in the axial direction of the model sample exhibits an uneven feature of more at the top and less at the bottom, and the distribution characteristics of porosity also show an uneven feature of more at the top and less at the bottom.

C28H41NO2, monoclinic, C2 (no. 5), a= 4.8622(5) Å, b= 6.7853(7) Å, c= 14.3349(17) Å, β= 96.556(3)°, V= 469.84(9) Å3, Z= 2, Rgt(F) = 0.0482, wRref(F2) = 0.1257, T = 284(2) K.

To examine the relationship between absent social support and depression among older adults from elderly care social organizations in Anhui Province, China.

C20H32O3, monoclinic, P21(no. 4), a= 7.8981(17) Å, b= 10.302(2) Å, c= 11.028(3) Å, β= 90.020(2)°, V= 897.3(3) Å3, Z= 2, Rgt(F) = 0.0603, wRref(F2) = 0.1342, T= 273(2) K.

C30H40O5, orthorhombic, P212121(no. 19), a= 6.5012(3) Å, b= 15.3297(7) Å, c= 21.8138(14) Å, V= 2672.3(2) Å3, Z= 4, Rgt(F) = 0.0537, wRref(F2) = 0.1355, T = 273(2) K.

C24H30O7, orthorhombic, P212121(no. 19), a= 11.4194(5) Å, b= 13.4657(6) Å, c= 14.7549(7) Å, V= 2268.86(18) Å3, Z= 4, Rgt(F) = 0.0535, wRref(F2) = 0.1239, T = 273(2) K.

MnO nanoparticles catalysis covered carbon with endoplasmic-reticulum-like structure serves as separator coating to enhance polysulfides conversion in lithium-sulfur batteries.

Objective: To validate and use the Chinese Version of the M. D. Anderson Symptom Inventory (MDASI-C) to assess the symptom burden of breast cancer patients in China. Methods: A total of 342 breast cancer patients in China participated in this study. Their symptoms were investigated with the MDASI-C from November 2020 to February 2021, and the reliability and validity of this tool were evaluated, respectively. Cluster analysis and correlation analysis were also performed. Results: The Cronbach’s alpha coefficient values of the symptom and interference items were 0.827 and 0.880, respectively. Construct validity revealed a four-factor structure. The Kaiser—Meyer—Olkin value was 0.760. The Karnofsky Performance Status, treatment phase, and cancer stage of the patients were grouped, and the differences of scores within the groups were significant. In addition, the employment status, education level, and age of the patients were significantly correlated with the symptoms. The correlation analysis of the education level of the patients showed that most of the symptoms and interference items were reduced as the education level was increased. The top three symptoms were disturbed sleep (3.10±2.52), difficulty remembering (2.54±2.30), and fatigue (2.24±2.13). The clinical and biochemical indicators such as body mass index and neutral granulocyte lymphocyte ratio had effects on many symptoms. As the patients’ BMI increased, the patients’ pain, disturbed sleep, and difficulty remembering were aggravated, and numbness was alleviated. Conclusion: The MDASI-C is a reliable and effective assessment tool to evaluate patients with breast cancer in China. The symptoms are related to many clinical and biochemical indicators.

In this work, we study secure and trusted authentication of unmanned aerial vehicles (UAVs) in 5G networks. Existing centralized UAV identity authentication mechanisms may only be able to verify the identity of the UAV itself or manage pilots, which are far from complete protection of legal access. Some recent works on UAV identity management are based on blockchain technology, in which UAV identities are generated through the blockchain software wallets, so they may be vulnerable to UAV identity forgery. To tackle the challenges described above, we propose an authentication mechanism based on a dual-identity (dual-ID) model for UAVs in 5G networks via a cross-layer design of SIM cards, blockchain, and smart contracts. The proposed self-sovereign UAV identity management procedure will then jointly process the authentications of both the UAV device and its pilot through the blockchain hardware wallets embedded in 5G SIM cards. In this way, a global registry of a unique identifier of each UAV device and each pilot can be ensured, and the identity forgery problem can also be avoided. Due to the limited power and processing capacity of UAV devices and the need of quick response for authentication, we employ 5G and multi-access edge computing (MEC) servers for communication and processing. To validate the proposed solution, a developed proof-of-concept system is tested through the 5G MEC testbed at National Taiwan University to demonstrate the flexibility and usability of UAV authentication.

Although sleep, physical activity and sedentary behavior have been found to be associated with dementia risk, findings are inconsistent and their joint relationship remains unclear. This study aimed to investigate independent and joint associations of these three modifiable behaviors with dementia risks. A total of 431,924 participants (median follow-up 9.0 years) without dementia from UK Biobank were included. Multiple Cox regressions were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Models fitted with restricted cubic spline were conducted to test for linear and nonlinear shapes of each association. Sleep duration, leisure-time physical activity (LTPA), and screen-based sedentary behavior individually associated with dementia risks in different non-linear patterns. Sleep duration associated with dementia in a U-shape with a nadir at 7 h/day. LTPA revealed a curvilinear relationship with dementia in diminishing tendency, while sedentary behavior revealed a J-shaped relationship. The dementia risk was 17% lower in the high LTPA group (HR[95%CI]: 0.83[0.76–0.91]) and 22% higher in the high sedentary behavior group (1.22[1.10–1.35]) compared to the corresponding low-level group, respectively. A combination of seven-hour/day sleep, moderate-to-high LTPA, and low-to-moderate sedentary behavior showed the lowest dementia risk (0.59[0.50–0.69]) compared to the referent group (longer or shorter sleep/low LTPA/high sedentary behavior). Notably, each behavior was non-linearly associated with brain structures in a pattern similar to its association with dementia, suggesting they may affect dementia risk by affecting brain structures. Our findings highlight the potential to change these three daily behaviors individually and simultaneously to reduce the risk of dementia.

Particle swarm optimization (PSO) is an artificial intelligence technique that can be used to find approximate solutions to extremely difficult or impossible numeric optimization problems. Recently, PSO algorithms have been widely used in solving complex financial optimization problems. This paper presents a PSO approach to solve a portfolio construction problem, since this methodology is a population‐based heuristic algorithm that is suitable for solving high‐dimensional constrained optimization problems. The computational results show that PSO algorithms have advantages in optimizing the Sortino ratio, especially in speed, when the size of the portfolio is large.

Two generations of garnet are recognized in a granite and a pegmatite from the Gangdese orogen in southeastern Tibet on the basis of a combined study of petrography, major and trace element profiles, and garnet O isotopes. Zircon U-Pb dating and Hf-O isotope compositions also help constrain the origin of both granite and pegmatite. The first generation of garnet (Grt-I) occurs as residues in the center of garnet grains, and it represents an early stage of nucleation related to magmatic-hydrothermal fluids. Grt-I is dark in backscattered electron (BSE) images, rich in spessartine, and poor in almandine and grossular. Its chondrite-normalized rare earth element (REE) patterns show obvious negative Eu anomalies and depletion in heavy REE (HREE) relative to middle REE (MREE). The second generation of pegmatite garnet (Grt-II) occurs as rims of euhedral garnets or as patches in Grt-I domains of the pegmatite, and it crystallized after dissolution of the preexisting pegmatite garnet (Grt-I domains) in the presence of the granitic magma. Compared with Grt-I, Grt-II is bright in BSE images, poor in spessartine, and rich in almandine and grossular contents. Its chondrite-normalized REE patterns exhibit obvious negative Eu anomalies but enrichment in HREE relative to MREE. The elevation of grossular and HREE contents for Grt-II relative to Grt-I domains indicate that the granitic magma had higher contents of Ca than the magmatic-hydrothermal fluids. The garnets in the granite, from core to rim, display homogenous profiles in their spessartine, almandine, and pyrope contents but increasing grossular and decreasing REE contents. They are typical of magmatic garnets that crystallized from the granitic magma. Ti-in-zircon temperatures demonstrate that the granite and pegmatite may share the similar temperatures for their crystallization. Grt-II domains in the pegmatite garnet have the same major and trace element compositions as the granite garnet, suggesting that the pegmatite Grt-II domains crystallized from the same granitic magma. Therefore, the pegmatite crystallized at first from early magmatic-hydrothermal fluids, producing small amounts of Grt-I, and the fluids then mixed with the surrounding granitic magma. The U-Pb dating and Hf-O isotope analyses of zircons from the granite and pegmatite yield almost the same U-Pb ages of 77–79 Ma, positive εHf(t) values of 5.6 to 11.9, and δ18O values of 5.2 to 7.1‰. These data indicate that the granite and pegmatite were both derived from reworking of the juvenile crust in the newly accreted continental margin prior to the continental collision in the Cenozoic.

Multi-electron reaction can be regarded as an effective way of building high-energy systems (>500 W h kg−1). However, some confusions hinder the development of multi-electron mechanisms, such as clear concept, complex reaction, material design and electrolyte optimization and full-cell fabrication. Therefore, this review discusses the basic theories and application bottlenecks of multi-electron mechanisms from the view of thermodynamic and dynamic principles. In future, high-energy batteries, metal anodes and multi-electron cathodes are promising electrode materials with high theoretical capacity and high output voltage. While the primary issue for the multi-electron transfer process is sluggish kinetics, which may be caused by multiple ionic migration, large ionic radius, high reaction energy barrier, low electron conductivity, poor structural stability, etc., it is urgent that feasible and versatile modification methods are summarized and new inspiration proposed in order to break through kinetic constraints. Finally, the remaining challenges and future research directions are revealed in detail, involving the search for high-energy systems, compatibility of full cells, cost control, etc.

Flood frequency in river source regions is significantly affected by rainfall and snowmelt as part of climatic changes. A traditional univariate flood frequency analysis cannot reflect the complexity of floods, and when used in isolation, it can only underestimate flood risk. For effective flood prevention and mitigation, it is essential to consider the combined effects of precipitation and snowmelt. Copula functions can effectively quantify the joint distribution relationship between floods and their associated variables without restrictions on their distribution characteristics. This study uses copula functions to consider a multivariate probability distribution model of flood peak flow (Q) with cumulative snowmelt (CSm) and cumulative precipitation (CPr) for the Hutubi River basin located in northern Xinjiang, China. The joint frequencies of rainfall and snowmelt floods are predicted using copula models based on the Coupled Model Intercomparison Project Phase 6 data. The results show that Qhas a significant positive correlation with 24-d CSm (r= 0.559, p= 0.002) and 23-d CPr (r= 0.965, p< 0.05). Flood frequency will increase in the future, and mid- (2050‒2074) and long-term (2075‒2099) floods will be more severe than those in the near-term (2025‒2049). The probability of flood occurrence is higher under the SSP2-4.5 and SSP1-2.6 scenarios than under SSP5-8.5. Precipitation during the historical period (1990–2014) led to extreme floods, and increasing future precipitation trends are found to be insignificant. Snowmelt increases with rising temperatures and occurs earlier than estimated, leading to an earlier flood period in the basin and more frequent snowmelt floods. The Qunder the joint return period is larger than that during the same univariate return period. This difference indicates that neglecting the interaction between precipitation and snowmelt for floods leads to an underestimation of the flood risk (with underestimations ranging from 0.3% to 22%). The underestimations decrease with an increase in the return period. The joint risks of rainfall or snowmelt according to various flood periods should be considered for rivers with multi-source runoff recharge in flood control design. This study reveals the joint impact of precipitation and snowmelt on extreme floods under climate change in river source regions. This study also provides a scientific basis for regional flood prevention and mitigation strategies, as well as for the rational allocation of water resources.

Frozen ground (FG) plays an important role in global and regional climates and environments through changes in land freeze‒thaw processes, which have been conducted mainly in different regions. However, the changes in land surface freeze‒thaw processes under climate change on a global scale are still unclear. Based on ERA5-Land hourly land skin temperature data, this study evaluated changes in the global FG area, global land surface first freeze date (FFD), last freeze date (LFD) and frost-free period (FFP) from 1950 to 2020. The results show that the current FG areas (1991–2020 mean) in the Northern Hemisphere (NH), Southern Hemisphere (SH), and globe are 68.50 × 106, 9.03 × 106, and 77.53 × 106 km2, which account for 72.4%, 26.8%, and 60.4% of the exposed land (excluding glaciers, ice sheets, and water bodies) in the NH, SH and the globe, respectively; further, relative to 1951–1980, the FG area decreased by 1.9%, 8.8%, and 2.8%, respectively. Seasonally FG at lower latitudes degrades to intermittently FG, and intermittently FG degrades to non-frozen ground, which caused the global FG boundary to retreat to higher latitudes from 1950 to 2020. The annual FG areas in the NH, SH, and globe all show significant decreasing trends (p < 0.05) from 1950 to 2020 at −0.32 × 106, −0.22 × 106, and −0.54 × 106 km2per decade, respectively. The FFP prolongation in the NH is mainly influenced by LFD advance, while in the SH it is mainly controlled by FFD delay. The prolongation trend of FFP in the NH (1.34 d per decade) is larger than that in the SH (1.15 d per decade).

Binary soil mixtures are extensively used in the construction of geothermal-related earth structures such as geothermal energy piles (GEP), ground source heat pumps (GSHP) and earth air tunnel heat exchangers (EATHE). An evaluation of the binary soil’s thermal-mechanical properties is the key process in determining the final performance of geothermal-related projects. Therefore, the thermal-mechanical properties of binary soil mixtures were systematically investigated in this paper. A series of thermal and mechanical property tests was conducted on five sand-kaolin clay mixtures with sand contents ranging from 0% to 100% by dry weight. The experimental results indicated that the sand-clay mixtures achieved the theoretically densest state when the sand content reached the critical threshold. The further the binary mixture’s sand content was from the critical threshold, the lower the mixture’s density was. As the sand content increased, the shear stress-strain curves gradually shifted from strain-softening behavior to strain-hardening behavior due to the decrease in suction stress. The relationship between the sand content and the shear strength of the mixtures exhibited an “S” shape, which is attributed to the interaction between the sand and clay particles and varied with the sand contents. The shear wave velocity of the sand clay mixtures was found to decrease continuously with the increase in sand content until the sand skeleton had formed. In addition, the thermal conductivity of the binary mixed soil changed linearly with the sand content, and the upper bound of the critical threshold interval (77%) was found to separate the two different heat conduction modes. Finally, an elastic shear modulus (G0) model, which correlated to the tangent elastic modulus of the binary mixture (Em), and a more generalized thermal conductivity (K) model were formulated for the binary sand-clay mixtures, and the effectiveness and feasibility of the proposed models were validated by comparing the values predicted with the model and the experimental data.

In order to determine the appropriate model for predicting the maximum surface settlement caused by EPB shield tunneling, three artificial neural network (ANN) methods, back-propagation (BP) neural network, the radial basis function (RBF) neural network, and the general regression neural network (GRNN), were employed and the results were compared. The nonlinear relationship between maximum ground surface settlements and geometry, geological conditions, and shield operation parameters were considered in the ANN models. A total number of 200 data sets obtained from the Changsha metro line 4 project were used to train and validate the ANN models. A modified index that defines the physical significance of the input parameters was proposed to quantify the geological parameters, which improves the prediction accuracy of ANN models. Based on the analysis, the GRNN model was found to outperform the BP and RBF neural networks in terms of accuracy and computational time. Analysis results also indicated that strong correlations were established between the predicted and measured settlements in GRNN model with MAE = 1.10, and RMSE = 1.35, respectively. Error analysis revealed that it is necessary to update datasets during EPB shield tunneling, though the database is huge.

The Dabie–Sulu orogenic belt in east-central China contains one of the largest ultrahigh-pressure (UHP) metamorphic terranes in the world. The UHP eclogites are associated with gneiss, peridotite and marble. But all these rocks underwent in situUHP metamorphism during the continental collision in the Triassic. Although fluid action is not significant during cold subduction, it becomes prominent during hot exhumation of UHP slices. Whereas the composition of UHP metamorphic rocks is primarily inherited from their protoliths, they were locally modified by partial melting to varying extents. The partial melting of UHP rocks is highly heterogeneous along the collisional orogen, and achieves a maximum during rifting orogeny at the post-collisional stage. This paper outlines the petrographical features and geochemical compositions of UHP metamorphic rocks, and presents an overview of collisional modification and post-collisional reworking of the subducted continental crust. Further discussions are devoted to continental subduction tectonics, as well as to subduction style, subduction polarity and exhumation mechanism. The results also provide insights into the initiation of continental rifting in a Wilson cycle. Consequently, studies of the Dabie–Sulu orogenic belt have contributed greatly to our understanding of tectonic processes, fluid regime and chemical geodynamics in continental subduction zones.

Objective: In order to generate induced Pluripotent Stem Cells (iPSCs) more efficiently, it is crucial to identify somatic cells that are easily accessible and possibly require fewer factors for conversion into iPSCs. Methods: Human epidermal melanocytes were transduced with lentiviral vectors carrying 3 transcription factors (OCT-4, KLF-4 and c-MYC, 3F) or 4 transcription factors (OCT-4, KLF-4, c-MYC and SOX-2, 4F). Once the clones had formed, assays related to stem cell pluripotency, including alkaline phosphatase staining, DNA methylation levels, expression of stem cell markers and ultrastructure analysis were carried out. The iPSCs obtained were then induced to differentiate into the cells representing the three embryonic layers in vitro. Results: Seven days after the transduction of epidermal melanocytes with 3F or 4F, clones were formed that were positive for alkaline phosphatase staining. Fluorescent staining with antibodies against OCT-4 and SOX-2 was strongly positive, and the cells showed a high nucleus-cytoplasm ratio and active karyokinesis. No melanosomes were found in the cytoplasm by ultrastructural analysis. There were obvious differences in DNA methylation levels between the cloned cells and their parental cells. However, there was not a significant difference between 3F or 4F transfected clonal cells. Meanwhile, the iPSCs successfully differentiated into the three germ layer cells in vitro. Conclusion: Human epidermal melanocytes do not require ectopic SOX-2 expression for conversion into iPSCs, and may serve as an alternative source for deriving patient-specific iPSCs with fewer genetic elements.

ABSTRACTInfluenza is a significant public health threat associated with high morbidity and mortality globally. This study investigated the influenza vaccination rate (IVR) among community residents in Anhui province, China, and explored the association between participants’ influenza vaccination and their key sociodemographic characteristics, perception of COVID-19 as well as COVID-19 vaccination behavior. We found that the IVR among respondents in Anhui province was 27.85% in 2020. Regression analyses revealed that males (OR = 1.41, 95% CI: 1.01 ~ 1.96), residents with above middle school education (OR = 1.88, 95% CI: 1.04 ~ 3.39), considered themselves likely to be infected with COVID-19 (OR = 1.53, 95% CI: 1.04 ~ 2.24), had received the COVID-19 vaccine (OR = 9.85, 95% CI: 3.49 ~ 27.78), did not plan to receive COVID-19 vaccine in the future (OR = 1.70, 95% CI: 1.17 ~ 2.47), and had no adverse reactions after COVID-19 vaccination (OR = 1.54, 95% CI: 1.04 ~ 2.27) were associated with a higher IVR. The acceptance of influenza vaccination was mainly associated with respondents’ gender, education, perception of COVID-19, history of COVID-19 vaccination in city and countryside community residents in Anhui province.

The speedy growth of the semiconductor industries and global water scarcity issues have caused great demand for energy-saving water reclamation technologies such as forward osmosis (FO). Magnetic nanoparticles functionalized with osmotic polymer were believed to be one of the emerging materials used as the drawing solute in FO because they can be simply recovered with magnet. This study employed a novel strategy to prepare an FO drawing solute that balances the tradeoff between the amount of surface-immobilized ionic polymer for generating osmotic pressure and particle size with strong magnetization for ensuring steady recovery. The drawing solute was designed to be applied to the FO reclamation of water from the wastewater generated during the diamond wire sawing of Si ingots. Coprecipitation and polyol reduction were employed to synthesize poly(sodium acrylate)-functionalized magnetic nanoparticles (PSA-MNPs) as the drawing solute. The polyol route produced particles (PSA-MNPpolyol) sized 150–220 nm and composed of spherical subunits sized 3–5 nm. By contrast, coprecipitation resulted in irregular aggregated clusters and discrete 3–8-nm particles (PSA-MNPcp). Adding the electrostatic stabilizer sodium acetate to the precursor in the coprecipitation route (creating PSA-MNPcp+AC) significantly improved the particles’ dispersion and slightly increased their osmolality. When the optimal concentration of iron precursor was employed, the saturation magnetization and the osmolality of the PSA-MNPpolyolreached 45.89 emu/g and 258 mOsmol/kg, respectively. The average water flux generated when PSA-MNPpolyolwas employed as the drawing solute was approximately 3.8 times higher than that generated when PSA-MNPcp+ACwas used over a 3-h FO process on waste produced by ingot sawing. The homogeneous particle sizes of PSA-MNPpolyolare conductive to post-FO recovery through magnetic separation.