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Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Minimal residual disease (MRD) is proposed to be responsible for tumor recurrence. The role of circulating tumor DNA (ctDNA) to detect MRD, monitor recurrence, and predict prognosis in liver cancer patients undergoing liver transplantation (LT) remains unrevealed. Methods: Serial blood samples were collected to profile ctDNA mutational changes. Baseline ctDNA mutational profiles were compared with those of matched tumor tissues. Correlations between ctDNA status and recurrence rate (RR) and recurrence-free survival (RFS) were analyzed, respectively. Dynamic change of ctDNA was monitored to predict tumor recurrence. Results: Baseline mutational profiles of ctDNA were highly concordant with those of tumor tissues (median, 89.85%; range 46.2–100%) in the 74 patients. Before LT, positive ctDNA status was associated with higher RR (31.7% vs 11.5%; p = 0.001) and shorter RFS than negative ctDNA status (17.8 vs 19.4 months; p = 0.019). After LT, the percentage of ctDNA positivity decreased (17.6% vs 47.0%; p < 0.001) and patients with positive ctDNA status had higher RR (46.2% vs 21.3%; p < 0.001) and shorter RFS (17.2 vs 19.2 months; p = 0.010). Serial ctDNA profiling demonstrated patients with decreased or constant negative ctDNA status had lower RR (33.3% vs 50.0%; p = 0.015) and favorable RFS (18.2 vs 15.0 months, p = 0.003) than those with increased or constant positive ctDNA status. Serial ctDNA profiling predicted recurrence months ahead of imaging evidence and serum tumor biomarkers. Conclusions: ctDNA could effectively detect MRD and predict tumor recurrence in liver cancer patients undergone LT. [ABSTRACT FROM AUTHOR]

As a biodegradable polyester, the commercialized synthesis protocol of poly(ε-caprolactone) (PCL) under mild conditions is of great significance and attractive. Herein, the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) using FeCl3 catalyst and benzyl alcohol (BnOH) as the initiator was developed. FeCl3 has been proved to be an efficient catalyst for the ROP of ε-CL under mild conditions. The conversion of ε-CL to PCL was 98.8% at 60 °C within 4 h, with number-average molecular weight (Mn) and dispersity (PDI) of 1.65 × 104 g/mol and 1.28, respectively. Moreover, a coordination-insertion ring-opening polymerization mechanism mediated by FeCl3 was proposed. Overall, this work is expected to provide a feasible industrial method for the preparation of PCL from the direct aerobic oxidation of cyclohexanone. [ABSTRACT FROM AUTHOR]

Subsidence data acquisition methods are crucial to mining subsidence research and an essential component of achieving the goal of environmentally friendly coal mining. The origin and history of the existing methods of field monitoring, calculation, and simulation were introduced. It summarized and analyzed the main applications, flaws and solutions, and improvements of these methods. Based on this analysis, the future developing directions of subsidence data acquisition methods were prospected and suggested. The subsidence monitoring methods have evolved from conventional ground monitoring to combined methods involving ground-based, space-based, and air-based measurements. While the conventional methods are mature in technology and reliable in accuracy, emerging remote sensing technologies have obvious advantages in terms of reducing field workload and increasing data coverage. However, these remote sensing methods require further technological development to be more suitable for monitoring mining subsidence. The existing subsidence calculation methods have been applied to various geological and mining conditions, and many improvements have already been made. In the future, more attention should be paid to unifying the studies of calculation methods and mechanical principles. The simulation methods are quite dependent on the similarity of the model to the site conditions and are generally used as an auxiliary data source for subsidence studies. The cross-disciplinary studies between subsidence data acquisition methods and other technologies should be given serious consideration, as they can be expected to lead to breakthroughs in areas such as theories, devices, software, and other aspects. [ABSTRACT FROM AUTHOR]

Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and water. Such strategy was less developed in organocatalyzed polymerization and frequently regarded as side reactions. Herein, one-component phosphonium borane Lewis pairs PB1–PB8 were successfully applied in the copolymerization of CO2 and cyclohexene oxide (CHO) to generate poly(CHO-alt-CO2) carbonate (PCHC). Parameters of linker length and counter anion effects on the catalyst activity were investigated. It was found that Lewis pair PB3 served as a dual initiator and catalyst in the copolymerization of CHO and CO2 with or without the presence of water. In contrast, Lewis pair PB8 can serve as a true catalyst for the preparation of well-defined α,ω)-hydroxyl PCHC diols. This was achieved by introducing a labile CF3COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer agents. The function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was proposed. Upon changing the amount of water and catalyst loading, PCHC diols with varied molecular weight (1.5 kg/mol to 7.5 kg/mol), low dispersities (Ð<1.2) and carbonate content (>99%) could be easily obtained. The low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide (LLA) to afford ABA triblock copolymer in one-pot synthesis. [ABSTRACT FROM AUTHOR]

Abstract The development of chronic obstructive pulmonary disease (COPD) pathogenesis remains unclear, but emerging evidence supports a crucial role for inducible bronchus‐associated lymphoid tissue (iBALT) in disease progression. Mechanisms underlying iBALT generation, particularly during chronic CS exposure, remain to be defined. Oxysterol metabolism of cholesterol is crucial to immune cell localization in secondary lymphoid tissue. Here, we demonstrate that oxysterols also critically regulate iBALT generation and the immune pathogenesis of COPD. In both COPD patients and cigarette smoke (CS)‐exposed mice, we identified significantly upregulated CH25H and CYP7B1 expression in airway epithelial cells, regulating CS‐induced B‐cell migration and iBALT formation. Mice deficient in CH25H or the oxysterol receptor EBI2 exhibited decreased iBALT and subsequent CS‐induced emphysema. Further, inhibition of the oxysterol pathway using clotrimazole resolved iBALT formation and attenuated CS‐induced emphysema in vivo therapeutically. Collectively, our studies are the first to mechanistically interrogate oxysterol‐dependent iBALT formation in the pathogenesis of COPD, and identify a novel therapeutic target for the treatment of COPD and potentially other diseases driven by the generation of tertiary lymphoid organs.

We investigate the problem when the tensor functor by a bimodule yields a singular equivalence. It turns out that this problem is equivalent to the one when the Hom functor given by the same bimodule induces a triangle equivalence between the homotopy categories of acyclic complexes of injective modules. We give conditions on when a bimodule appears in a pair of bimodules, that defines a singular equivalence with level. We construct an explicit bimodule in a combinatorial manner, which yields a singular equivalence between a quadratic monomial algebra and its associated algebra with radical square zero. Under certain conditions which include the Gorenstein cases, the bimodule does appear in a pair of bimodules defining a singular equivalence with level. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic liver resection (LLR) has now been established as a safe and minimally invasive technique that is deemed feasible for treating hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). However, the role of LLR in treating combined hepatocellular-cholangiocarcinoma (cHCC-CC) patients has been rarely reported. This study aimed to assess the efficacy of LLR when compared with open liver resection (OLR) procedure for patients with cHCC-CC. Methods: A total of 229 cHCC-CC patients who underwent hepatic resection (34 LLR and 195 OLR patients) from January 2014 to December 2018 in Zhongshan Hospital, Fudan University were enrolled and underwent a 1:2 propensity score matching (PSM) analysis between the LLR and OLR groups to compare perioperative and oncologic outcomes. Overall survival (OS) and recurrence-free survival (RFS) parameters were assessed by the log-rank test and the sensitivity analysis. Results: A total of 34 LLR and 68 OLR patients were included after PSM analysis. The LLR group displayed a shorter postoperative hospital stay (6.61 vs. 8.26 days; p value < 0.001) when compared with the OLR group. No significant differences were observed in the postoperative complications' incidence or a negative surgical margin rate between the two groups (p value = 0.409 and p value = 1.000, respectively). The aspartate aminotransferase (AST), alanine aminotransferase (ALT), and inflammatory indicators in the LLR group were significantly lower than those in the OLR group on the first and third postoperative days. Additionally, OS and RFS were comparable in both the LLR and OLR groups (p value = 0.700 and p value = 0.780, respectively), and similar results were obtained by conducting a sensitivity analysis. Conclusion: LLR can impart less liver function damage, better inflammatory response attenuation contributing to a faster recovery, and parallel oncologic outcomes when compared with OLR. Therefore, LLR can be recommended as a safe and effective therapeutic modality for treating selected cHCC-CC patients, especially for those with small tumors in favorable location. [ABSTRACT FROM AUTHOR]

Stabilized cadmium (Cd) was extremely easy to be re-released into the environment. The study was aim to explore the Cd removal efficiency and passivation in paddy soil by magnetic hydroxyapatite loaded biochar (MHBC), and to investigate the effect of MHBC on Cd accumulation and yield of rice with low Cd accumulation cultivar named ZhuLiangYou189 (ZLY189) and conventional cultivar named ZhuLiangYou929 (ZLY929) in 2-year field trials. These results shown that MHBC under the high dosage of 25.2 t/ha can effectively decrease the bioavailable Cd (from 0.4 to 0.24 mg/kg) and total Cd (from 1.42 to 0.86 mg/kg). For ZLY929, only with the dosage of 25.2 t/ha MHBC, the grain Cd content can meet the contaminant limits in grain (≤ 0.2 mg/kg) during 2 years. While for ZLY189, the grain Cd content in 6.3 t/ha, 12.5 t/ha, and 25.2 t/ha decreased to 0.13 ~ 0.17 mg/kg, to 0.07 ~ 0.10 mg/kg, and to 0.05 ~ 0.08 mg/kg during 2 years, respectively. What's more, the application of MHBC has no environmental risk and increase grain yield by boosting soil nutrient substance. Thus, the application of MHBC was a promising remediation technology in Cd-contaminated paddy soil. [ABSTRACT FROM AUTHOR]

Farmland abandonment, a widespread phenomenon during land-use transition, leads to a cycling or vanishing evolution of farmland resources. As urbanization advances, an increasing number of agricultural laborers migrate from rural to urban areas, causing ongoing farmland abandonment. However, in contrast to the abandoned information extraction and driving mechanisms revelation, the potential risk of farmland abandonment has received insufficient attention. This study took Yangtze River Economic Belt of China as study area, selected multiple aspects to construct a risk assessment system for farmland abandonment, and applied time series change detection to verify the results. The results showed that (1) farmland abandonment risk, with a regional average value of 0.0978, has strong spatial heterogeneity, with high values clustering in Yunnan-Guizhou and Sichuan-Chongqing mountainous areas and low values distributed in the midstream and downstream plains and the Sichuan Basin. (2) The proportion of farmland area gradually decreased as the risk grade increased. Farmland, with low abandonment risk, occupied an area of 204,837 km2, constituting the highest percentage of 35.18% among the overall farmland, and was mainly distributed in the provinces of Jiangsu and Anhui. The area of farmland with high risk was 16,458 km2, only accounting for 2.83%, the majority of which was clustered in Sichuan and Yunnan provinces. (3) The Normalized Difference Vegetation Index (NDVI) time series change detection validated the reliability of the risk assessment system. Samples of farmland having low abandonment risk indeed had the lowest abandonment rate of 10%, and those which indicated high risk had the highest abandonment rate of 32%. We propose differentiated managements for farmland resources with high and low abandonment risk from the perspective of sustainable use. This study provides a more reasonable and scientific system for farmland abandonment risk assessment and helps to fill the research gap. [ABSTRACT FROM AUTHOR]

In this paper, the predefined-time formation control problem of nonlinear multiagent systems is investigated by using the leader–follower control structure, in which agents are categorized into two types: leaders and followers. The leader determines the desired trajectory for a group of agents by selecting the control parameters. The followers update their actual positions with the specified local positions between themselves and the leader. Formation controls in the presence of practical problems with unknown bounded external disturbances, saturated input, and predefined-time convergence constraints under the directed topology are considered. To achieve the control objective with the consideration of different physical constraints, the general and saturated formation control laws are first presented, their stability analyses are provided, and the asymptotic stability of multiagent systems is ensured. Furthermore, according to two given formation approaches, an explicit smooth solution to the problem of predefined-time formation maneuver control is obtained. The settling time of the proposed predefined-time formation strategy for the followers can be determined by the system parameters, which are independent of the initial positions of the coefficient corresponding to the relative velocities of the agents. Finally, numerical simulations are carried out to illustrate the feasibility and efficacy of the obtained theoretical results. [ABSTRACT FROM AUTHOR]

Urban waterbodies are one of the most pertinent issues involved in multiple aspects of Sustainable Development Goals (SDGs). However, waterbodies in large Chinese cities are highly vulnerable to urban-land expansion, which is mostly due to economic development, population growth, and rural–urban migration. In this work, we selected 159 Chinese cities of over one million in population to investigate the encroachment on waterbodies due to rapid urbanization from 1990 to 2018. Overall, 20.6% of natural waterbody area was lost during this period to urban expansion, and this fraction varied from city to city which was related to waterbody abundance. With the acceleration of urbanization, waterbody occupation is becoming more serious (P < 0.01). However, in all cities, this encroachment has eased since 2010, which justifies the effective implementation of national-scale policies to conserve urban waterbodies. Meanwhile, gains have occurred during urbanization, in addition to the loss of waterbodies. Especially, cities lacking waterbody placed a greater emphasis on ecological factors, whose urban waterbody areas showed an increasing trend. In the future, ecological resources, including waterbody, should be considered in urban planning to provide reasonable protection to waterbodies in the quest for urban sustainability. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study an amphiphilic polymer has been designed, produced and evaluated. Poly(butylacrylate-maleic anhydride) (PBMA) has been prepared and modified by monomethoxypolyethylene glycol (PEG) with formation of an amphiphilic polymer (PEG–PBMA). Demulsification efficiency of PEG–PBMA and commercially available chemical demulsifiers has been studied in a simulated heavy crude oil emulsion (Liaohe Oil Field) by the bottle test method. The results demonstrate that demulsification efficiency of PEG–PBMA, AE-121, TA-1031, and SP-169 can reach 86.6, 76.4, 68.0, and 54.6%, respectively. The studies have revealed that PEG–PBMA can find potential application as efficient demulsifier for breaking crude oil emulsion, especially for heavy crude oil emulsions. [ABSTRACT FROM AUTHOR]

Opencast coal mining has a large impact on the land surface, both at the mining pits themselves and at waste sites. After artificial management is stopped, a reclaimed opencast coal mine dump is affected by wind and water erosion from natural processes, resulting in land degradation and even safety incidents. In this paper, the soil erosion and land degradation after 5 years of such natural processes, at the Xilinhot opencast coal mine dump in Inner Mongolia, were investigated. A multi-source data acquisition method was applied: the vegetation fraction coverage (VFC) was extracted from GF-1 satellite imagery, high-precision terrain characteristics and the location and degree of soil erosion were obtained using a drone, and the physical properties of the topsoil were obtained by field sampling. On this basis, the degree and spatial distribution of erosion cracks were identified, and the causes of soil erosion and land degradation were analyzed using the geographical detector. The results show that (1) multi-source data acquisition method can provide effective basic data for the quantitative evaluation of the ecological environment at dumps, and (2) slope aspect and VFC are the main factors affecting the degree of degradation and soil erosion. Based on above analysis, several countermeasures are proposed to mitigate land degradation: (1) The windward slope be designed to imitate the natural landform. (2) Reasonable engineering measures should be applied at the slope to restrain soil erosion. (3) The Pioneer plants should be widely planted on the platform at the early stage of reclamation. [ABSTRACT FROM AUTHOR]

Conservation management usually carried out for a period of time to maintain the vegetation restoration of coal waste dumps after reclamation. However, the natural restoration of vegetation is faced with great challenges in semi-arid mining areas without management, due to the fragile ecological environment. Therefore, it is necessary to determine a reasonable management plan so that vegetation restoration can reach a stable state although the abandonment of the management. The objective was to explore the difference of vegetation restoration under different management modes in a typical semi-arid mining area. Two reclaimed coal waste dumps under different management measures, the north waste dump (ND) and the south waste dump (SD), were examined in the ShengLi coalfield in Inner Mongolia, China. The normalized difference vegetation index (NDVI) dataset based on Landsat series imagery was obtained using the Google Earth Engine (GEE) platform, and the landscape metrics were also calculated based on different vegetation coverage. The results proved that 3 years of management was not enough to stabilize vegetation restoration. A serious vegetation degradation occurred at the ND after the management stopped, with 40.1% of the pixels recorded a significant decrease (ρ = 0.05). The vegetation coverage became fragmented, and there was a tendency of succession to lower coverage. On the contrary, the vegetation restoration of SD was better under continuous management, and no significant degradation trend was observed. Furthermore, the results indicated that rainfall is the main influencing factor on vegetation restoration in semi-arid mining areas. The coal waste dump was more susceptible to weather change in natural restoration. By contrast, continuous management measures will resist such climate disturbances, even in dry years. This research will provide support for the formulation of the reclamation management plan of coal waste dumps in semi-arid mining areas. [ABSTRACT FROM AUTHOR]

In this paper, we mainly study a diffusive Leslie–Gower prey–predator model by the geometric singular perturbation theory. Under assumptions that the diffusion rate of prey is much smaller than that of predator and the natural growth rate of prey is much greater than that of predator, we use dimensionless transformation and traveling wave transformation to transform the diffusive Leslie–Gower prey–predator model into a Multi-scale slow-fast system with two small parameters of different magnitude. According to the Tikhonov–Finichel singular perturbation theory, we analyse the Multi-scale dynamics with respect to two small parameters in turn. Furthermore, we prove the existence of heteroclinic orbit for the slow-fast system. Thus, we get the existence of travelling waves of original reaction-diffusion model. Finally, numerical examples are given to support our theoretical results. [ABSTRACT FROM AUTHOR]

The evolution of oxygenic photosynthesis is a pivotal event in Earth’s history because the O2 released fundamentally changed the planet’s redox state and facilitated the emergence of multicellular life. An intriguing hypothesis proposes that hydrogen peroxide (H2O2) once acted as the electron donor prior to the evolution of oxygenic photosynthesis, but its abundance during the Archean would have been limited. Here, we report a previously unrecognized abiotic pathway for Archean H2O2 production that involves the abrasion of quartz surfaces and the subsequent generation of surface-bound radicals that can efficiently oxidize H2O to H2O2 and O2. We propose that in turbulent subaqueous environments, such as rivers, estuaries and deltas, this process could have provided a sufficient H2O2 source that led to the generation of biogenic O2, creating an evolutionary impetus for the origin of oxygenic photosynthesis. [ABSTRACT FROM AUTHOR]

Underground coal mining leads to land subsidence, and the situation is particularly serious in the Coal-Grain Complex in eastern China, causing the crop production to be reduced or to be taken out. Backfilling with Yellow River sediment is one of the effective methods to solve the land subsidence in this area, but a key issue is how to select the optimal soil reconstruction profile so that the crop yield after backfilling and reclamation is unaffected. The main purpose of this study is to verify the feasibility of selecting the optimal soil reconstruction profile by rapid monitoring of crop growth and judging soil quality with the aid of unmanned aerial vehicle systems (UAVs). A control treatment and 13 experimental treatments were established for the study area. The control treatment consisted of using 30 cm topsoil and 90 cm subsoil and the topsoil is a proxy for native (undisturbed) soil from the study sites. All other treatments consisted of using varying combinations of subsoil and sediment overlain by 30 cm of topsoil. The vegetation indices from the UAV multispectral images, and the plant height and vegetation coverage from the UAV RGB images were used for estimation of the winter wheat biomass in a random forest regression. The results showed that the random forest regression model yielded accurate estimation of the aboveground biomass. Furthermore, knowledge of plant height and vegetation coverage improved the accuracy of prediction such that crop growth was well characterized. The optimal soil profile consisted of 0.3 m topsoil + 0.2 m subsoil + 0.2 m sediment + 0.2 m subsoil + 0.3 m sediment. A fast and effective airborne monitoring method for soil quality was established, thus providing greatly improved monitoring efficiency. [ABSTRACT FROM AUTHOR]

Purpose: The underground mining of coal leads to land subsidence and changes agricultural land into a water-logged area. This study aims to examine the relationship between coal mining subsidence and crop failure in plains with a high underground water table. Methods: The Dongtan Coal Mine in Jining City of Shandong Province in China was selected as an example. Samples were gathered at gradient intervals based on the strike, dip, and angular bisector directions. The spatial variability and spatial correlation were analyzed by combining classical statistics and geostatistics. Results: The order of the coefficient of variation in each parameter was as follows: the available phosphorus > available potassium > leaf area index (LAI) > biomass > soil moisture content > chlorophyll content (SPAD) > soil organic matter (SOM) > alkaline nitrogen (AN) > bulk density > elevation. Except the biomass had moderately spatially dependent, the other parameters all exhibited a strongly spatially dependent. At the level of 0.01, the correlation coefficient between SOM and AN was 0.67. The correlation coefficients relating biomass with SPAD and LAI were 0.70 and 0.69, respectively, and between SPAD and LAI was 0.68. The correlation coefficients between distance and altitude, distance and biomass, and altitude and biomass are 0.95, 0.67, and 0.65, respectively. Conclusion: Coal mining leads to stretching and deformation of the ground, land subsidence, and changes in the physicochemical properties of the soil. In this case, the yield of aboveground crops is poor, but under the influence of external factors such as irrigation and breeding, the threat of coal mining to crop growth has been reduced. [ABSTRACT FROM AUTHOR]

Leclercia sp. W6 and W17, which belong to the Enterobacteriaceae, were isolated from a stomach sample from a 78-year-old female gastric cancer patient, and genomic sequencing and analysis were performed. The genome of Leclercia sp. W6 consists of one chromosome with a size of 4,945,486 bp, while that of Leclercia sp. W17 contains one chromosome and two plasmids with a total size of 5,125,645 bp. Average nucleotide identity (ANI) calculations indicated that strains W6 and W17 exhibited similarities < 91.0% to other strains within the Enterobacteriaceae, except for six Leclercia strains. Phylogenomic analysis based on core-genome showed that strains W6 and W17 belong to the genus Leclercia, and phylogenetic analysis based on ANI values revealed that strains W6 and W17 formed an independent clade from those six Leclercia strains. Furthermore, comparative genomic analysis revealed that strains W6 and W17 had 5086 orthologous clusters (OCs) in their pan-genomes, and 59 exclusive OCs which were absent in their closest relatives. Genomic annotations revealed that the genomes of strains W6 and W17 encoded genes related to multidrug resistance clusters, multiple antibiotic resistance loci, and multidrug efflux pumps and had an identical urease gene cluster and a dissimilatory nitrate reduction pathway. Bioinformatic analyses indicated that strains W6 and W17 represented a novel species within the genus Leclercia. Genomic annotations revealed that these strains encoded genes related to multidrug resistance, nitrate reduction, and urease activity, which contribute to gastric malignant transformation. This will broaden our knowledge of the genetic mechanisms of the Enterobacteriaceae and help improve the clinical conditions of gastric cancer patients. [ABSTRACT FROM AUTHOR]

Soil fungi have been widely studied, but the effects of heavy metal contamination at various levels as well as the abundance and diversity of heavy metal tolerant fungi in the contaminated paddy soils are still unknown. The purpose of this study is to analyze the adaptability of fungi at different levels of heavy metal contamination to identify species that have strong adaptability to heavy metals. In this research, the technology of high-throughput sequencing was applied to study fungal communities in severe level (SL), moderate level (ML), light level (LL), and clean level (CL) for soil samples polluted by heavy metal, as well as to analyze the relations between environmental variables and fungal communities. The spearman analysis showed that 6 dominant fungal phyla and 18 dominant fungal genera were significantly correlated with these environmental variables. The α-diversity indexes of the soil fungal community from SL, ML, and CL were, mostly, drastically higher than the LL samples (p < 0.05). Meanwhile, Ascomycota, the main fungal phylum, was spotted to yield a strong tolerance towards heavy metals, especially in ML. The most dominant genera of tolerant fungi in this area, which are Aspergillus, Penicillium, and Fusarium, could absorb and transport the heavy metals with the help of nutrients under certain heavy metal contamination levels. Therefore, this study indicated that some fungi, which have strong biodegradability on heavy metals, can reduce toxicity of heavy metals and create a proper soil environment to grow food crops. [ABSTRACT FROM AUTHOR]

In eastern China, coal mining has damaged a large amount of farmland, posing a great threat to food security. Backfilling with coal waste, fly ash, and sediments from rivers is an effective method to restore farmland. This study was conducted at the reclaimed area (RA) and the undisturbed area (UA) in Shandong Province, China. Soil and plant analyzer development (SPAD) of corn was selected as an indicator of crop growth. Multi-spectral data was obtained by the unmanned aerial vehicle equipped with a camera. By analyzing the correlation between SPAD and spectral bands, the common vegetation index is improved. Different regression methods were used to construct the SPAD inversion model. The distribution of corn SPAD was monitored to objectively evaluate reclamation technology. The results are as follows: (1) the vegetation index improved using the red-edge band has a higher correlation with SPAD, and the largest coefficient of determination (R2) value is 0.779; (2) the optimum inversion model for both jointing stage (R2 = 0.676) and milky stage (R2 = 0.661) is the linear regression model; the optimum model for both tasseling stage (R2 = 0.809) and filling stage (R2 = 0.830) is the partial least squares regression model; (3) the SPAD inversion map of RA and UA obtained by the optimum model shows that the corn grown in RA is slightly better than in UA. This study realized the rapid and efficient monitoring of the reclamation effects based on multi-spectral imagery and verified the feasibility of backfilling reclamation with Yellow River sediment in coal mining subsidence areas. [ABSTRACT FROM AUTHOR]

Underground coal mining inevitably causes land subsidence, while negatively impacting land and ecological environments. This is particularly severe in coal-grain overlap areas (CGOA) in eastern China, which have high groundwater levels. Mining subsidence has substantially altered the original topography, and raised the groundwater level, which threatens grain security in the region. Therefore, it is necessary to determine the damaged farmland area in the CGOA. The traditional method to define the range of coal mining disturbance is usually based on surface subsidence. However, this fails to consider the multidimensional impacts of coal mining on the ecology, which is considered unreasonable. Therefore, this paper introduces a low-cost, fast, and non-destructive method for land damage assessment in a typical CGOA in eastern China, using maize aboveground biomass (AGB) as estimated from an unmanned aerial vehicle (UAV). There were three key results from the survey. (1) underground coal mining caused significant ecological problems in the study area, including subsidence (approximately 6 m) and the degradation of vegetation (maize AGB in a range of 192.73–1338.06 g/m2). In addition, the degradation of maize was affected by subsidence (0.61** Pearson coefficient found between the AGB and surface elevation). (2) An UAV combined with multispectral and digital cameras, allowed precise estimation of the AGB and the red-edge chlorophyII index (CIrededge) combined with the elevation factor had the best explanatory power using the random forest (RF) method (R2 = 0.96, RMSE = 65.03 g/cm2). (3) The maize AGB could be used to assess land damage affected by underground coal mining, which accounted for 82.12% of the study area. The results of the study could provide a reference for land damage assessments in the CGOA, while also providing a guide for land reclamation and agricultural management decisions in the region. [ABSTRACT FROM AUTHOR]

Due to high gas content, high geo-stress and complex geological conditions, gas disasters occur frequently in deep coal mining. The hard thick roof (HTR) greatly increases the difficulty of coalbed gas control besides causing dynamic disasters. In this paper, the effects of HTR on gas migration were numerically analyzed based on a multi-field coupling model. Results indicated that the hanging arch leads to remarkable stress concentration and induces a "cap-shaped" low-permeable zone above the gob, which greatly prevents gas from migrating upwards. Meanwhile, HTR hinders the subsidence movements of the upper rock strata, contributing to very few roof fractures and bed-separated fractures. Without the formation of roof-fractured zone, coalbed gas completely loses the possibility of upward concentration and will accumulate in the gob, forming a major safety hazard. To overcome these problems, borehole artificially guided pre-splitting (BAGP) technology was proposed. Three different pre-splitting boreholes were constructed as a group to generate artificial fractures in advance in HTR via deep-hole blasting, promoting the evolution of roof fractures. With the effects of mining stress, a fracture network is eventually formed in HTR, which provides a preferential passage for the upward flow of coalbed gas. Moreover, the controllable breaking of HTR was achieved and the roof strata could deform and subside regularly, forming an "O-shaped" roof-fractured zone above the gob which greatly improves the gas extraction efficiency of roof high-level boreholes. In addition, after BAGP, several extraction measures can be applied in the gob-side entry to drain the gas in different concentrated areas. In the field experiment, the roof periodic breaking length was reduced by half, and the average gas extraction rate was increased by 4 times to 67.7%. The synergetic controls of HTR and coalbed gas were effectively realized. This study provides valuable insight into gas control in other deep coal mines with similar geological conditions. [ABSTRACT FROM AUTHOR]

Optical sensors, such as fiber interferometers transmit along light paths and perform measurements based on optical path difference. These types of sensors can reduce device volume and improve sensing performance using optical multiplexing. A beam splitter for optical path multiplexing in an optical fiber ring is proposed. A photonic crystal was used to design the beam splitter. By optimizing and improving the photonic crystal microstructure, the beam splitting function can be realized while taking into account the cycling capability. Therefore, the light can recirculate multiple times in the fiber ring to realize light path multiplexing. The finite difference time domain method is used to analyze and evaluate the performance of the beam splitter. [ABSTRACT FROM AUTHOR]

When a high-speed droplet impacts on mesh screens, part of the droplet penetrates the screen through its pores and generates smaller secondary drops, which spray downstream in a conical distribution. This instantaneous phase fragmentation phenomenon has been widely utilized in liquid spray applications and multiple-phase liquid separation. During droplet deformation, the intense liquid–gas fragmentation can lead to high nonequilibrium effect, which makes it hard to simulate by traditional fluid computational method. In this study, for the first time, we provided a numerical method to simulate the entire process of penetration dynamic behaviors. This 3D droplet-impact model based on MDPD (many-body dissipative particle dynamics) method exhibits high stability. A special solid–liquid boundary condition was proposed and successfully reduced the massive computational resources wasted on the solid mesh surface. To verify our model, the impacting of a droplet on a flat surface and on a mesh screen were simulated, respectively. The result showed a good match with our previous drop impact study and our experiment of the whole process about a droplet fragmented into hundreds of small drops. We further studied the mass transfer ratio (the ratio of penetrated drops to the initial droplet) and the ejection angle (the angle of the spray cone). The mass transfer ratio and ejection angle can be approximated as a function of Weber number, solid fraction and mesh number by summarizing the regular drop-penetrated behaviors over initial speed and mesh number. [ABSTRACT FROM AUTHOR]

To explore the specimen size effect of mechanical behavior of ultrafine-grained (UFG) materials with different structures, UFG Al sheets processed by equal channel angular pressing (ECAP) were selected as target materials and the dependency of tensile behavior on sheet thickness (t) was systematically investigated. The strength and ductility of ECAPed UFG Al sheets were improved synchronously as t increased from 0.2 to 0.7 mm, and then no apparent change occurred when t reached to 0.7 and 1.0 mm. The corresponding microstructure evolved from dislocation networks in equiaxed grains into the walls and subgrains and finally into the dominated cells in elongated grains or subgrains. Meanwhile, dense shear lines (SLs) and shear bands (SBs) were clearly observed and microvoids and cracks were initiated along SBs with the increase of t. These observations indicated that the plastic deformation of UFG Al sheets was jointly controlled by shear banding, dislocation sliding, and grain-boundary sliding. Furthermore, the propagation of SBs became difficult as t increased. Finally, the obtained results were discussed and compared with those of annealed UFG Al and UFG Cu. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the emergence and development of unmanned aerial vehicles (UAVs), different sensors have become more miniaturized and intelligent. UAVs equipped with various sensors are now an important approach for acquiring spatial data. Many advantages, such as low cost, short revisiting cycle, flexibility and high precision, have made UAVs powerful tools in geological, agricultural, ecological and forestry growth monitoring, as well as evaluation. Now, UAVs are a hotspot in scientific research. Their application in mining areas (MA), although still in its infancy, is developing rapidly in terms of speed, scale and service scope. This research examines aspects such as UAV platforms, different sensors and their application fields, as well as reviewing the advances of scientific research in MA at the present time. By combining current research and the functions of multiple sensors, an application framework for UAV monitoring in MA is constructed. Finally, the challenge and prospects for the development of UAVs and sensors are also considered. This research hopes to provide a technical reference, expanding the knowledge and recognition of UAV monitoring in MA, as well as an assessment of applications in mining, reclamation and environment. [ABSTRACT FROM AUTHOR]

Different types of cloth show distinctive appearances owing to their unique yarn-level geometrical details. Despite its importance in applications such as cloth rendering and simulation, capturing yarn-level geometry is nontrivial and requires special hardware, e.g., computed tomography scanners, for conventional methods. In this paper, we propose a novel method that can produce the yarn-level geometry of real cloth using a single micro-image, captured by a consumer digital camera with a macro lens. Given a single input image, our method estimates the large-scale yarn geometry by image shading, and the fine-scale fiber details can be recovered via the proposed fiber tracing and generation algorithms. Experimental results indicate that our method can capture the detailed yarn-level geometry of a wide range of cloth and reproduce plausible cloth appearances. [ABSTRACT FROM AUTHOR]

Background: Resveratrol exerts an anti-inflammatory effect on collagen-induced arthritis and osteoarthritis in rats via activation of sirtuin 1 (SIRT1). Autophagy can be induced by resveratrol and leads to amelioration of interleukin-1 beta (IL-1β) release in vitro. We aimed to determine the anti-inflammatory mechanisms of resveratrol in patients with gout. Methods: Blood samples were obtained from patients with acute gout, intercritical gout (IG) and healthy controls (HC). The mRNA and protein levels of SIRT1 and nuclear factor-kappa B (NF-kB) p65 were determined in peripheral blood mononuclear cells (PBMCs) lysate from these patients. In the in vitro experiment, SIRT1, autophagy-related genes (beclin-1 and microtubule-associated protein 1 light-chain 3) and key genes involved in the gouty inflammatory pathway, including NF-κB p65, NLR family pyrin domain containing 3 (NLRP3), caspase-1 and IL-1β, were determined in PBMCs lysate or plasma from IG patients exposed to monosodium urate (MSU) crystals with or without resveratrol. Results: The mRNA and protein levels of SIRT1 were downregulated in PBMCs from gout patients in comparison with HC. In the in vitro experiment, the protein levels of SIRT1 were downregulated in PBMCs from IG patients exposed to MSU crystals and were restored by resveratrol in a dose-dependent manner. Furthermore, high doses of resveratrol ameliorated the release of the inflammatory cytokine IL-1β. In addition, the mRNA levels of NLRP3 and NF-κB p65 were regulated by resveratrol, but caspase-1 and IL-1β were not. Furthermore, resveratrol promoted MSU-induced autophagy in PBMCs from patients with gout. Conclusion: These findings suggest that resveratrol ameliorates gouty inflammation via upregulation of SIRT1 to promote autophagy in patients with gout. [ABSTRACT FROM AUTHOR]

Objective: To explore brain activations associated with electroacupuncture simulation at Tongli (HT 5) and its comparison with brain activations during picture-naming task.Methods: Twenty healthy subjects were enrolled in this study. Half of them received electroacupuncture stimulation at HT 5 (ACUP group) and the other half of them received stimulation at a nonmeridian sham acupoint (SHAM group). All subjects performed picture-naming task. Each subject finished two runs of functional magnetic resonance imaging examinations in one session and picture-naming task was performed before electroacupuncture stimulation. Subjective brain activations were obtained using generalized linear model and inter-group analyses were performed after that.Results: The electroacupuncture stimulation at HT 5 induced significant brain activations in both the anterior and posterior language regions, including the left inferior frontal gyrus, which was in consistent with activations induced during picture-naming task. Group analysis showed a tendency of increased activation of ACUP group in left inferior frontal gyrus compared with SHAM group (P<0.05 FDR corrected).Conclusions: Electroacupuncture treatment at the acupoint HT 5 has modulation effect on typical language-implicated brain regions in healthy subjects, which provides supporting evidence for beneficial effects of needling at HT 5 for recovery of language function in aphasia. [ABSTRACT FROM AUTHOR]

Unfertilized ovary culture constitutes an effective method for haploid breeding and can greatly shorten the breeding time. This method has been successfully used for breeding in many species, but reports of this method for breeding watermelon are scarce. Therefore, we performed an experiment to induce haploid plantlets. We evaluated the effects of several important factors on unfertilized ovary cultures of watermelon, including genotype, medium, the duration of induction and the development stage of the ovaries. The results revealed that the genotype of donor plants was a key factor for in vitro gynogenesis. The induction rate of eight watermelon cultivars varied from 0.00 to 15.14 ELSs per100 ovary slices. The most effective induction medium and maturation medium were MS medium supplemented with 3 mg L− 1 2,4-D, 2 mg L− 1 BAP, 0.5 mg L−1 NAA and MS supplemented with 0.8 mg L− 1 BAP and 0.2 mg L− 1 NAA, respectively. The duration of induction significantly influenced ELS formation. The optimum duration was 13 days, and unfertilized ovaries collected at anthesis had the higher induction rate. We obtained more than 100 plantlets and used chromosome counting and flow cytometry to determine the ploidy levels of 50 of them, among which 48 were haploid and 2 were diploid. Our results demonstrated that in vitro gynogenesis can be induced in watermelon by unfertilized ovaries culture. [ABSTRACT FROM AUTHOR]

We characterized fetal and placental growth and uterine and placental inflammation in pregnant C3H/HeOuJ and C57BL/6J mice (strains with different sensitivities to metabolic and circulatory pathologies), using different uterine ischemia/reperfusion (I/R) protocols, to establish and refine a murine model of I/R-induced fetal growth restriction (FGR). Pregnant C3H/HeOuJ mice on gestation day 15 were subjected to unilateral uterine I/R by (1) total blood flow restriction (TFR) by occlusion of the right ovarian and uterine arteries for 30 minutes, (2) partial flow restriction (PFR) by occlusion of only the right ovarian artery for 30 minutes, or (3) sham surgery. Pregnant C57BL/6J mice were treated the same, but on gestation day 14 and with TFR for only 5 minutes due to high sensitivity of C57BL/6J mice to I/R. Four days post-I/R, the animals were euthanized to determine fetal and placental weight and fetal loss and to assay placental myeloperoxidase (MPO) activity. In C3H/HeOuJ mice, TFR/30 minutes induced significantly (P < .05) lower fetal and placental weights and higher placental MPO activity, compared to controls. The PFR/30 minutes produced the same effects except placental weights were not reduced. In contrast, in C57BL/6J mice, TFR for only 5 minutes was sufficient to induce FGR and increase fetal loss; while PFR/30 minutes lowered fetal but not placental weights and increased fetal loss but not placental MPO activity. In summary, we present the first published model of I/R-induced FGR in mice. We find that mice of different strains have differing sensitivities to uterine I/R, therefore differing I/R response mechanisms. [ABSTRACT FROM AUTHOR]

To explore the influence of cyclic pre-deformation on the mechanical behavior of ultrafine-grained (UFG) materials with a high stacking fault energy (SFE), UFG Al processed by equal-channel angular pressing (ECAP) was selected as a target material and its tensile behavior at different pre-cyclic levels D (D = Ni / Nf, where Ni and Nf are the applied cycles and fatigue life at a constant stress amplitude of 50 MPa, respectively) along with the corresponding microstructures and deformation features were systematically studied. The cyclic pre-deformation treatment on the ECAPed UFG Al led to a decrease in flow stress, and a stress quasi-plateau stage was observed after yielding for all of the different-state UFG Al samples. The yield strength σYS, ultimate tensile strength σUTS, and uniform strain ɛ exhibited a strong dependence on D when D ≤ 20%; however, when D was in the range from 20% to 50%, no obvious change in mechanical properties was observed. The micro-mechanism for the effect of cyclic pre-deformation on the tensile properties of the ECAPed UFG Al was revealed and compared with that of ECAPed UFG Cu through the observations of deformation features and microstructures. [ABSTRACT FROM AUTHOR]

We propose an automatic garment seam modeling framework to create a garment model with the seam structure from a single image. In order to achieve this, a marked seam image database and parametric seam models have been set up. Given a real seam image, we first identify the type of the seam image based on our marked seam image database and the seam parameters are parsed automatically by our sewing thread estimation method. Second the seam initial model is generated through the pre-defined parametric seam models. A garment model with the seam structure is finally obtained based on the seam position information which users have marked on the garment. Moreover, we verify the effectiveness of our method with numerous experiments. [ABSTRACT FROM AUTHOR]

At present, the error control process of the complex thin-walled workpiece mainly adopts the error suppression and error elimination; the effectiveness of error control depends on the cognition of the process designer about machine accuracy and the error-generating mechanism. This paper proposes a new compensation method to control errors in machining thin-walled workpieces based on the inverse reconstruction model. In this method, the thin-walled workpiece is represented by discrete point cloud (DPC) for error analysis; according to the unified error prediction model, the DPC positions can be obtained companying with the machining errors. Then the new DPC is reconstructed into the workpiece model used inverse reconstruction model. At the same time, a fairing algorithmis developed to deal with the smoothing problem of DPC. So, the new workpiece model is used instead of the original for processing. By this method, the machining precision and surface quality of thin-walled workpieces are ensured. In addition, a case study is presented to demonstrate the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Inflammation plays a crucial role in the pathogenesis of stroke. This study aims to determine lipoprotein (a) [Lp(a)] levels in serum and to investigate their associations with stroke recurrence events in a 3-month follow-up study in patients with acute ischemic stroke (AIS). Serum Lp(a) levels were determined in 203 ischemic stroke patients and 120 normal controls at admission. The severity and clinical outcome of ischemic stroke patients were evaluated by the National Institutes of Health Stroke Scale (NIHSS). We followed the participants for a median of 3 months using a standard questionnaire to determine the stroke recurrence events. The correlation analysis and multiple linear regression analysis were performed. Compared with controls, serum Lp(a) levels were significantly increased in ischemic stroke patients than in controls. NIHSS scores and infarct volume were positively correlated with Lp(a) (P < 0.001). Finally, 34 patients (16.7%; 95% CI, 11.6–21.9%) had a stroke recurrence. Serum Lp(a) levels in patients with recurrent stroke were significantly higher as compared with those in patients without recurrent stroke (P < 0.001). In multivariate analysis, there was an increased risk of stroke recurrence associated with Lp(a) levels ≥300 mg/l (OR, 2.87; 95% CI, 1.98–4.32; P = 0.009) after adjusting for possible confounders. With an AUC of 0.872 (95% CI, 0.816–0.927), Lp(a) showed a significantly greater discriminatory ability to predict stroke recurrence as compared with NIHSS score (AUC, 0.782; 95% CI, 0.704–0.859; P < 0.01). Our findings suggest that elevated serum Lp(a) levels can predict the risk of early stroke recurrence in patients with first-ever ischemic stroke. Further research is needed to replicate these findings. [ABSTRACT FROM AUTHOR]

Background: The studies comparing laparoscopic and open central pancreatectomy with pancreaticojejunostomy are limited. This study aimed to compare clinical outcomes and quality of life of patients undergoing laparoscopic and open central pancreatectomy with pancreaticojejunostomy.Methods: Between December 1997 and December 2015, patients who underwent central pancreatectomy with pancreaticojejunostomy were reviewed. Patients were divided into 2 groups as laparoscopic central pancreatectomy (LCP) and open central pancreatectomy (OCP). Data considered for comparison analysis were patient demographics, intraoperative variables, morbidity, postoperative hospital stay, mortality, pathologic findings, and quality of life (SF-36 questionnaire).Results: Thirty-six patients (17 LCP and 19 OCP) were included in the final analysis. Baseline characteristics were similar in the 2 groups. The operating time (280.4 ± 33.6 vs. 290.5 ± 62.5 min, p = 0.455) were similar between two groups. LCP group showed significantly lower estimated blood loss (76.4 ± 70.3 vs. 390.3 ± 279.0 ml, p = 0.001), shorter first flatus time (2.4 ± 0.9 vs. 3.9 ± 1.3 days, p = 0.001), and shorter diet start time (4.1 ± 2.2 vs. 6.1 ± 2.4 days, p = 0.030). However, the postoperative hospital stay was not significantly different between two groups (15.6 ± 12.1 vs. 24.0 ± 27.5 days, p = 0.347). Postoperative outcomes, including morbidity (58.8 vs. 52.6%, p = 0.749), pancreatic fistula rates (≥grade B: 17.6 vs. 36.8%, p = 0.106), and mortality, were similar in the 2 groups. The median follow-up period was 45 months (range 4-216 months). No local recurrence or distant metastasis was detected in either group. On the follow-up survey, the total quality of life score (702.9 ± 47.9 vs. 671.8 ± 94.1), physical health score (353.9 ± 24.8 vs. 326.6 ± 67.6) and mental health score (349.0 ± 26.5 vs. 345.2 ± 34.6) were higher in the LCP group compared with the OCP group. However, these differences were not statistically significant (p > 0.05). The score in role physical (100 vs. 73.1 ± 4.8, p = 0.042) was significantly higher in LCP group, and not statistically significant in other areas (p > 0.05).Conclusions: LCP with pancreaticojejunostomy is safe and feasible for benign or borderline malignant lesions in the pancreatic neck and proximal body. Compared to OCP, LCP is associated with lower estimated blood loss, faster recovery, and better quality of life. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For an additive category with a Serre duality and a finite group action, we compute explicitly the Serre duality on the category of equivariant objects. We prove that under certain conditions, the equivarianzation of an additive category with a periodic Serre duality still has a periodic Serre duality. A similar result is proved for fractionally Calabi-Yau triangulated categories. [ABSTRACT FROM AUTHOR]

The interaction of continuous wave (CW) fiber laser with Ti-6Al-4V alloy is investigated numerically and experimentally at different laser fluence values and ambient pressures of N2 atmosphere to determine the melting time threshold of Ti-6Al-4V alloy. A 2D-axisymmetric numerical model considering heat transfer and laminar flow is established to describe the melting process. The simulation results indicate that material melts earlier at lower pressure (8.0 Pa) than at higher pressure (8.8×10 Pa) in several milliseconds with the same laser fluence. The experimental results demonstrate that the melting time threshold at high laser fluence (above 1.89×10 W/m) is shorter for lower pressure (vacuum), which is consistent with the simulation. While the melting time threshold at low laser fluence (below 1.89×10 W/m) is shorter for higher pressure. The possible aspects which can affect the melting process include the increased heat loss induced by the heat conduction between the metal surface and the ambient gas with the increased pressure, and the absorption variation of the coarse surface resulted from the chemical reaction. [ABSTRACT FROM AUTHOR]