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In this article, the effect of a chamber's geometrical parameters on suppressing gas explosion propagation was studied. Three rectangular chambers were used in the study, with a constant length of 0.5 m, a constant height of 0.2 m, and a variable width of 0.3 m, 0.5 m, and 0.8 m; each chamber was installed in a pipeline system for experimental research. The experimental results showed that when the chamber length and height were fixed at 0.5 m and 0.2 m, respectively, the suppression effect of the chamber on the explosion shockwave improves with the increase in the chamber width; when the chamber width increases to 0.8 m, the chamber has suppressive effect on explosion shockwave propagation. It was also found that the suppression effect of the chambers on the explosion flame improves with the increase in the chamber width; when the width of the chamber is 0.5 m, the chamber effectively suppresses explosion flames. Based on the experimental results, a numerical model was established to simulate the suppression effect of five types of chambers with a length, width, and height of 0.5 m × 0.3 m × 0.2 m, 0.3 m × 0.5 m × 0.2 m, 0.5 m × 0.5 m × 0.2 m, 0.5 m × 0.8 m × 0.2 m, and 0.8 m × 0.5 m × 0.2 m, respectively. The numerical simulation results indicated that when the chamber length and height are constant at 0.5 m and 0.2 m, respectively, the suppressive effect of the chamber on the shockwave improves as the chamber width increases; when the chamber width increases to 0.8 m, the shockwave overpressure at the chamber outlet is attenuated by 10.61%, indicating that the chamber suppresses the propagation of explosion shockwave, which is consistent with the experimental results obtained in the study. It was also found that when the chamber width and height were constant at 0.5 m and 0.2 m, respectively, as the chamber length increases, the overpressure increases first and then weakens. When the chamber length increases to 0.8 m, the overpressure at the chamber outlet is attenuated by −14.16%, indicating that the chamber is not able to suppress the propagation of explosion shockwave. Finally, a numerical simulation of the propagation process of a methane-air mixture and explosion flames in different chambers was performed to analyse the effect of chamber geometrical parameters on explosion suppression effect. [ABSTRACT FROM AUTHOR]

The objectives of this study were (i) to determine the stock and distribution of soil organic carbon (SOC) and the quantity and quality of fine root; and (ii) the correlation between SOC stock and fine root quantity and quality in soils of artificial and natural vegetation in the Loess Plateau. Three vegetation types (grassland, shrubland and woodland) and two restoration approaches (artificially and naturally restored from cropland) were investigated in the Yangou watershed of the Loess Plateau. SOC stock, fine root biomass and root C/N ratio at the 0–20, 20–40, 40–60, 60–80, and 80–100 cm depths were determined. The mean SOC stock of natural vegetation at the 0–100 cm depth was significantly greater than that of artificial vegetation, with an increase of 100% for woodland, 15% for shrubland, and 23% for grassland. Natural vegetation restoration led to a significantly greater SOC stock up to a depth of 100 cm for woodland, 40 cm for shrubland, and 40 cm for grassland. The fine root biomass of natural vegetation at the 0–100 cm depth was also significantly greater than that of artificial vegetation, with an increase of 170% for woodland, 140% for shrubland, and 20% for grassland. Natural vegetation restoration led to a significantly greater fine root biomass up to a depth of 100 cm for woodland, 60 cm for shrubland, and only 20 cm for grassland. There was a significant linear correlation between SOC stock and fine root biomass. Thus, natural vegetation restoration could lead to a significantly greater SOC stock, fine root biomass, and fine root C/N ratio than the artificial vegetation restoration. Fine root was an important factor influencing the differences in the SOC stock between artificial and natural vegetation. [ABSTRACT FROM AUTHOR]

Application of phosphorus (P) fertilizers to P-deficient soils can also result in P accumulation. In this study, soil P status and P uptake by apple trees were investigated in 5-, 10-, and 15-year-old orchards in the semi-arid Loess Plateau, China, and subset soils with different soil P statuses (14–90 Olsen-P mg kg−1) were selected to evaluate the characteristic P adsorption. Due to the low P-use efficiency (4–6%), total soil P increased from 540 mg kg−1 to 904 mg kg−1, Olsen-P ranged from 3.4 mg kg−1 to 30.7 mg kg−1, and CaCl2-P increased from less than 0.1 mg kg−1 to 0.66 mg kg−1 under continuous P fertilization. The P sorption isotherms for each apple orchard were found to fit the Langmuir isotherm model (R2 = 0.91–0.98). K (binding energy) and Qm (P sorption maximum) decreased, whereas DPS (degree of phosphorus sorption) increased with increasing P concentration. CaCl2-P increased significantly with the increase of Olsen-P, especially above the change point of 46.1 mg kg−1. Application of surplus P could result in P enrichment in P-deficient soil which has high P fixation capacity, thus posing a significant environmental risk. [ABSTRACT FROM AUTHOR]

A better understanding of the response of soil respiration to land-use conversion has important practical implications for ecological restoration in degraded regions. In this study, in situ soil respiration was monitored in a typical land-use sequence on a ridge slope in Wangdonggou watershed of the Loess Plateau, China, during a three-year period from 2011 to 2013. The land-use conversion sequences included cropland (control), apple orchard, grassland, and woodland. The results clearly showed that soil respiration and temperature sensitivity ( Q 10 ) varied significantly with land-use conversion. Soil respiration was decreased by 10% after conversion of cropland to orchard, and increased by 7–46% after conversion of cropland to grassland and woodland. Q 10 was increased by 19% after conversion of cropland to woodland, and decreased by 9–26% after conversion of cropland to grassland and orchard. Soil respiration increased linearly with soil organic carbon (SOC) storage and fine root biomass (<2 mm). The results indicated that root biomass and SOC storage were the major factors influencing Q 10 after conversion of cropland to non-natural ecosystem, and substrate quality or root system adaptability may be the real reason for the difference in Q 10 after conversion of cropland to natural grassland ecosystem. Although soil temperature and moisture significantly influenced soil respiration among the four typical land-use types, their difference derived from land-use conversions could not well explain the difference in soil respiration among land-use conversions. In conclusion, the increases in SOC storage and fine root biomass were the major factors influencing soil respiration among land-use conversions. Thus, conversion of cropland to natural grassland seemed to be the most effective integrated small watershed management to increase soil carbon storage and decrease CO 2 concentration in the loess regions of China. [ABSTRACT FROM AUTHOR]

Understanding the response mechanisms of litter respiration to soil moisture in water-limited semi-arid regions is of vital importance to better understanding the interplay between ecological processes and the local carbon cycle. In situ soil respiration was monitored during 2010–2012 under various conditions (normal litter, no litter, and double litter treatments) in a 30-year-old artificial black locust plantation (Robinia pseudoacacia L.) on the Loess Plateau. Litter respiration with normal and double litter treatments exhibited similar seasonal variation, with the maximum value obtained in summer (0.57 and 1.51 μmol m−2s−1 under normal and double litter conditions, respectively) and the minimum in spring (0.27 and 0.69 μmol m−2s−1 under normal and double litter conditions, respectively). On average, annual cumulative litter respiration was 115 and 300 g C m−2 y−1 under normal and double litter conditions, respectively. Using a soil temperature of 17°C as the critical point, the relationship between litter respiration and soil moisture was found to follow quadratic functions well, whereas the determination coefficient was much greater at high soil temperature than at low soil temperature (33–35% vs. 22–24%). Litter respiration was significantly higher in 2010 and 2012 than in 2011 under both normal litter (132–165 g C m−2 y−1 vs. 48 g C m−2 y−1) and double litter (389–418 g C m−2 y−1 vs. 93 g C m−2 y−1) conditions. Such significant interannual variations were largely ascribed to the differences in summer rainfall. Our study demonstrates that, apart from soil temperature, moisture also has significant influence on litter respiration in semi-arid regions. [ABSTRACT FROM AUTHOR]

The deformation behavior of the as-extruded Mg-Li-Al-Zn-Si alloy was studied by conducting a hot compression test, with a temperature range of 180–330 °C and a strain rate range of 0.01–10 s−1. The constitutive relationship of flow stress, temperature, and strain rate was expressed by the Zener–Hollomon parameter and included the Arrhenius term. By considering the effect of strain on the material constants, the flow stress at 240–330 °C could be precisely predicted with the constitutive equation (incorporating the influence of strain). A processing map was established at the strain of 0.7. The unsafe domains that are characterized by uneven microstructures were detected at low temperatures (<230 °C) or high temperatures (>280 °C), with high strain rates (>1 s−1). The optimum hot deformation region was obtained at a medium temperature (270–300 °C), with a peak power dissipation efficiency of 0.44. The microstructural evolution in different domains is investigated. The unstable domains are characterized by a non-uniform flow behavior and uneven microstructure. The observation showed that the dynamic recrystallization (DRX) process could easily occur at the safe domain with high power dissipation efficiency. For the α-phase, some features of continuous dynamic recrystallization can be found. The triple points serve as prominent nucleation sites for the β-phase DRX grains and the growth in the grains was carried out by subgrain boundary migration. The microstructure exhibits characteristics of discontinuous dynamic recrystallization. [ABSTRACT FROM AUTHOR]

Hot compression tests of the commercial Inconel 625 were performed in the temperature range of 950-1200 °C and strain rate range of 0.01-10 s. The flow behavior and processing maps were investigated using the corrected flow stress data to eliminate effects of the friction and adiabatic heating. The processing maps have exhibited a domain in the temperature range of 1100-1200 °C and strain rate range of 0.01-10 s corresponding to the higher efficiency of power dissipation. Microstructural observations reveal that the full dynamic recrystallization (DRX) occurs in this domain, which is optimum processing window for hot working to obtain a homogeneous microstructure. DRX grain growth occurs in the temperature range of 1150-1200 °C and strain rate range of 0.01-0.1 s. In view of the refined and uniform grains obtained by hot deformation, the finish forming processing should be selected the deformation conditions in which the full DRX occurs without the grain growth. The small regimes of flow instability are noticed at temperature below about 970 °C at the different strains. The material undergoes flow instability manifesting as bands of flow localizations and high density deformation twins. In addition, it is found that the undissolved second-phase particles and carbides can promote the DRX processing and be helpful to restrict the DRX grain growth. [ABSTRACT FROM AUTHOR]

Aims: Concerns over food security and global climate change require an improved understanding of how to achieve optimal crop yields whilst minimizing net greenhouse gas emissions from agriculture. In the semi-arid Loess Plateau region of China, as elsewhere, fertilizer nitrogen (N) inputs are necessary to increase yields and improve local food security. Methods: In a dryland annual cropping system, we evaluated the effects of N fertilizers on crop yield, its long-term impact on soil organic carbon (SOC) concentrations and stock sizes, and the distribution of carbon (C) within various aggregate-size fractions. A current version (RothC) of the Rothamsted model for the turnover of organic C in soil was used to simulate changes in SOC. Five N application rates [0 (N0), 45 (N45), 90 (N90), 135 (N135), and 180 (N180) kg N ha] were applied to plots for 25 years (1984-2009) on a loam soil (Cumulic Haplustoll) at the Changwu State Key Agro-Ecological Experimental Station, Shaanxi, China. Results: Crop yield varied with year, but increased over time in the fertilized plots. Average annual grain yields were 1.15, 2.46, 3.11, 3.49, and 3.55 Mg ha with the increasing N application rates, respectively. Long-term N fertilizer application increased significantly ( P = 0.041) SOC concentrations and stocks in the 0-20 cm horizon. Each kilogram of fertilizer N applied increased SOC by 0.51 kg in the top soil from 1984 to 2009. Using RothC, the calculated annual inputs of plant C (in roots, stubble, root exudates, etc.) to the soil were 0.61, 0.74, 0.78, 0.86, and 0.97 Mg C ha year in N0, N45, N90, N135 and N180 treatments, respectively. The modeled turnover time of SOC (excluding inert organic C) in the continuous wheat cropping system was 26 years. The SOC accumulation rate was calculated to be 40.0, 48.0, 68.0, and 100.0 kg C ha year for the N45, N90, N135 and N180 treatments over 25 years, respectively. As aboveground biomass was removed, the increases in SOC stocks with higher N application are attributed to increased inputs of root biomass and root exudates. Increasing N application rates significantly improved C concentrations in the macroaggregate fractions (>1 mm). Conclusions: Applying N fertilizer is a sustainable practice, especially in carbon sequestration and crop productivity, for the semiarid Loess Plateau region. [ABSTRACT FROM AUTHOR]

Abstract: The title compounds 3 and 4 were synthesized by reaction of 1,1′ ferrocenylenediol with the Co triple decker compounds [{(η5-Me5C5)Co}2(η6:η6-toluene)] and [{(η5-EtMe4C5)Co}2(η6:η6-toluene)], respectively. The central Co atom of 3 is coordinated by five O atoms in a square-pyramidal manner. The remaining two Co atoms of 3 are coordinated to a Me5C5 ligand in a η5-fashion and by the two O atoms of two 1,1′ ferrocenylenediolato ligands which serve as chelating ligands. In 4, the central Co atom is coordinated to all six O atoms of three ferrocenylenediolato ligands in a trigonal-prismatic manner, whereas the two other Co atoms are coordinated by an EtMe4C5 ligand in a η5-fashion and by three O atoms of three ferrocenylenediolato ligands resulting in an overall tripoidal structure for 4. [Copyright &y& Elsevier]

Abstract: The reaction of a mixture of sodium cyclopentadienide and the monolithium salt or dilithium salt of 2,2-bis(indenyl)propane with FeCl2 leads to the mononuclear complex [(η5-C5H5)Fe(η5-ind-C(CH3)2-ind)] (ind=1-indenyl) (1) and the dinuclear complex [{(η5-C5H5)Fe(η5-ind)}2C(CH3)2] (2), respectively. [(η5-Me5C5)Fe(tmeda)Cl] reacts with dilithium 1,1′-biindenyl under formation of [{(η5-Me5C5)Fe}2(μ-η5:η5-1,1′-biind)] (4). Due to the annelated arene rings of the η5-indenyl ligands, 2 and 4 may act as 4-electron donor ligands, as exemplified by the reaction with the triple-decker complex [{(η5-Me5C5)Co}2(μ-η6:η6-toluene)], which afforded the tetranuclear dimer of triple-decker complexes [{(η5-C5H5)Fe(η5-Me5C5)Co(μ-η5:η4-1-ind)}2C(CH3)2] (3) and the trinuclear complex [{(η5-Me5C5)Fe}2(η5-Me5C5)Co(μ3-η5:η4:η5-1,1′-biind)]·Et2O (5 ·Et2O) by replacement of the central toluene deck, respectively. The [(η5-Me5C5)Co] fragments of 3 and 5 are bonded via the six-membered rings of the indenyl ligands in a η4-fashion. Caused by the coordination to the Co atoms the six-membered rings lose their planarity and adopt a butterfly structure. The coordination geometry of the Fe atoms is similar in all five complexes. Each Fe atom is coordinated by the C atoms of one of the five-membered rings of the indenyl ligands in a slightly distorted η5 manner (η3 +η2-coordination) and by a cyclopentadienyl ligand in a regular η5-fashion. The structures of 3 and 5 represent the first examples of slipped triple-decker complexes which comprise indenyl ligands in a μ-η5:η4 coordination mode. [Copyright &y& Elsevier]

[Display omitted] • A multi-color fluorescence nanosensor based on Lap was manufactured. • It can realize the detection of tetracycline from 30 nM to 54 μM. • It was highly desirable for fulfilling the requirement for food quality. • Tetracycline can be recognized by chromaticity analysis APP on the smartphone. • It provided the possibility for the application in the field of intelligent devices. The emergence of "superbugs", which can cause great panic, has been proved to be related to the pollution of antibiotics in the environment water and food. It is of great research value to develop a portable, on-site and simple method for sensitive and selective detection of antibiotics. In this work, a laponite-based dual-channel fluorescent nanoprobe for the detection of tetracycline (TC) was manufactured through a simple assembly process. The nanoprobe can detect TC within two concentration channel from as low as 30 nM up to 54 μM with a detection limit of 9.5 nM, which met the needs in various analytical samples and showed excellent selectivity over various interferers. More significantly, the paper-based and glove-based visual probes were devised for the detection of TC by multi-color fluorescence change. And the tetracycline was also measured in milk, honey and lake after post-treatment of the samples. Combined with smartphone chromaticity analysis application (APP), the portable and disposable detection of TC can be realized. In addition, according to the fluorescence color change of the probe corresponding to the concentration of TC, two logic gates were also designed, which provided the possibility for the application of the probe in the field of smart devices. [ABSTRACT FROM AUTHOR]

Projected increases in the frequency and magnitude of extreme precipitation profoundly impact terrestrial ecosystems. However, the response of soil respiration to changing precipitation patterns has not been systematically investigated, especially in arid and semi-arid areas. Precipitation amounts of 300 and 600 mm (T300 and T600) were set to simulate normal and extremely wet summers, respectively, and were individually conducted by wetting soils in a series of sub-events—10 or 100 mm (P10, P100)—over equal time intervals. Maize straw (1300 kg ha−1) and N fertilization (200 kg N ha−1) were applied in parallel to extend our simulation to natural cropland conditions. Soil respiration pulses were observed after T300-P100, and inhibited effects occasionally occurred 1 day after T600-P100, primarily because frequent and harsh storms in T600-P100 induced saturation stress on soil respiration. Cumulative soil respiration in T600 was greater than that in T300, owing to prolonged suitable water conditions for soil respiration. Similarly, for the same total precipitation amount, P100 produced 40–44% more soil respiration than P10. Applying N and maize straw did not change response trends but produced different magnitudes of response to changing precipitation patterns. Maize straw significantly stimulated soil respiration, and this effect became more evident in P100 with improved water conditions, producing a 122–185% increase in cumulative soil respiration. Nitrogen slightly inhibited soil respiration; this effect was enhanced when maize straw was also added but was insignificant. Cumulative soil respiration was significantly correlated with β- d -glucosidase and soil microbial biomass carbon content. Such soil respiration responses highlight the need to accurately account for soil respiration contributions when projecting global carbon cycling in future climate scenarios. • Extreme precipitation events lead to soil respiration pulses, occasionally inhibiting and enhancing soil respiration rates. • Extreme precipitation patterns greatly enhanced the cumulative soil respiration. • Straw addition significantly amplified the response of soil respiration to extreme precipitation patterns. • N showed minor effects on soil respiration under extreme precipitation patterns. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) residues are harmful to the environment and human body, so it is necessary to develop a highly sensitive probe for rapid detection of tetracycline residues. In the present paper, a novel dye-doped porous metal–organic framework (UiO-66)-based multi-color fluorescent nano-probe was designed for sensitive ratiometric detection of tetracycline (TC). In this probe, dye-molecules doped UiO-66 was used as a fluorescent internal standard, and the externally grafted lanthanide Eu3+ complex was used as response signals. The fluorescence of the Eu3+ complex was selectively enhanced with increasing concentrations of TC, which was accompanied by a visual blue-to-red color switch. The nano-probe had a linear response between 0.1 and 6 μM with a lowest detection limit of 17.9 nM, which was much lower than the maximum residue limits set by the United States Food and Drug Administration (676 nM) and the European Union (225 nM). The applicability of this method in the analysis of actual samples was evaluated by the determination of TC in honey and milk samples, indicating satisfactory recovery and good reproducibility. In addition, a cost-effective paper-based probe for rapid and visual detection of TC was developed by fixing the nano-probe on filter papers. With the help of a smartphone camera to capture the fluorescence color, and chromaticity analysis software, the calculation and analysis of red (R) and blue (B) values can be realized, which has the potential for real-time visual detection of TC. [ABSTRACT FROM AUTHOR]

Numerous technological advancements in the 21st century depend on the creation of novel materials possessing enhanced properties; there is a growing reliance on materials that can be optimized to serve multiple functions. To efficiently save time and meet the requirements of diverse applications, high-throughput and combinatorial approaches are increasingly employed to explore and design superior materials. Among them, gradient thin-film deposition is one of the most mature and widely used technologies for high-throughput preparation of material libraries. This review summarizes recent progress in gradient thin-film deposition fabricated by magnetron sputtering, multi-arc ion plating, e-beam evaporation, additive manufacturing, and chemical bath deposition, providing readers with a fundamental understanding of this research field. First, high-throughput synthesis methods for gradient thin films are emphasized. Subsequently, we present the characteristics of combinatorial films, including microstructure, oxidation, corrosion tests, and mechanical properties. Next, the screening methods employed for evaluating these properties are discussed. Furthermore, we delve into the limitations of high-throughput preparation and characterization techniques for combinatorial films. Finally, we provide a summary and offer our perspectives. [ABSTRACT FROM AUTHOR]

Land use and topography are two primary factors that affect the spatial distribution of soil organic carbon (SOC) at the watershed scale, particularly in areas of multiple land uses and complex topography on the Loess Plateau. The General Linear Model (GLM) combined with Duncan’s Multiple Range Test (DMRT) were used to conduct variance tests and evaluate the effects of topography (summit, sloping areas and gullies), land use (farmland, orchard, grassland, shrubland and woodland), and their interactions on the vertical and horizontal distributions of SOC at soil depths of 0–10, 10–20, 20–40, 40–60, 60–80 and 80–100 cm. The effects of land use intensified from the summits to the slope areas to the gullies. The SOC concentrations throughout the 100 cm-thick soil profiles in farmland in slope areas and gullies were, respectively, 45.4% ( P < 0.0001) and 55.2% ( P < 0.0001) greater than those on the summits (3.1 g kg −1 ). In slope areas, the SOC concentrations in shrubland and grassland exceeded those in farmland (4.5 g kg −1 ) by 52.1% ( P < 0.0001) and 15.8%, respectively. In addition, in the gullies, the mean SOC concentrations in shrubland and grassland exceeded those in farmland (4.8 g kg −1 ) by 80.6% ( P < 0.0001) and 50.7% ( P = 0.0039), respectively. The SOC concentrations in areas of semi-shaded slope aspects were greater than those in areas of semi-sunny aspects. The enhanced effect of topographic position on SOC may be attributed to the vegetation and the soil conditions associated with the land uses and to the interactions between these variables at the watershed scale. These results could enhance understanding of the effects of environmental factors and their interaction on the spatial variation of SOC in regions with complex topography. These conclusions could have important implications for ecosystem recovery through rational land use changes in the ecologically fragile areas of the Loess Plateau and for improving the accuracy of prediction of SOC in regions of complex topography and land use on the Loess Plateau. [ABSTRACT FROM AUTHOR]

Glioma is a serious fatal type of cancer with the shorter median survival period and poor quality of living. The overall 5-year survival rate remains low due to high recurrence rates. Glioma stem cells (GSCs) play the important roles in the development of gliomas. Examination of the numerous biomarkers or cancer-associated genes involved in the development or prevention of glioma may therefore serve the discovery of novel strategies to treat patients with glioma. Hypoxia induced by using CoCl2 application and 14-3-3β protein knockdown by specific small interfering RNA transfection were performed in GSCs both in vitro and in vivo to observe their role in glioma progression and metastasis occurrence by using western blot analysis and MTT assay. The results demonstrated that CoCl2 application enhanced the 14-3-3β protein expression and mRNA levels via the PI3K pathway in GSCs. Furthermore, hypoxia promoted GSC cell proliferation and activated the expression of proliferating cell nuclear antigen, which was inhibited following 14-3-3β knockdown. In addition, tumor growth in mice was enhanced by CoCl2 application but reversed following 14-3-3β knockdown, which also enhanced GSC cell apoptosis. In conclusion, the present study demonstrated that hypoxia promoted glioma growth both in vitro and in vivo by increasing the 14-3-3β expression via the PI3K signaling pathway. 14-3-3β and HIF-1α may therefore be considered as the potential therapeutic target to treat patients with glioma. [ABSTRACT FROM AUTHOR]

Fungal communities play an important role in soil biogeochemical cycles and ecosystem function. The redistribution of water and soil causes significant differences in the soil physicochemical properties in eroding landscapes. However, changes in soil fungal diversity and key-stone taxa in soil-eroding catena remain poorly understood in these landscapes. In the current study, the diversity and key-stone taxa of the fungal community in topsoil samples were analyzed from three typical erosive topographic units (autonomous, transitional, and depositional zones). The Chao 1 index showed a decrease from the autonomous and transitional zones (1759.7 and 1752.6, respectively) to the depositional zone (1535.3), but there were no significant differences in the Shannon index. Transitional and depositional networks had fewer edges (318 and 387, respectively) and clustering coefficients (0.236 and 0.301, respectively) than the autonomous network (911 and 0.362, respectively). At the phylum level, the nutritional strategists of key-stone taxa tended to shift from r - to K-strategists along the soil-eroding catena, indicating that the majority of key-stone taxa were dominated by the phylum Ascomycota in the autonomous and transitional zones, whereas the phylum Basidiomycota was dominant in the depositional zone. The recalcitrant carbon composition (C C/C O, autonomous vs. transitional vs. depositional: 3.82 vs. 5.09 vs. 7.52) may have contributed to the decreased fungal richness along the soil-eroding catena. The primary controlling factors affecting key-stone taxa were soil organic carbon (SOC), total nitrogen (TN) and Olsen-P in the autonomous zone, SOC and C H/C O in the transitional zone, and C C/C O in the depositional zone. Exploring the changes in fungal diversity and key-stone taxa among different erosive topographic units can contribute to an in-depth understanding of the biogeochemical cycle in the eroding environment. • Fungal richness decreased along the soil-eroding catena. • High recalcitrant carbon content could induce low fungal richness in the depositional zone. • Fungal key-stone taxa tended to shift from r- to K-strategists along the soil-eroding catena. • Changes in soil properties could lead to spatial heterogeneity in fungal key-stone taxa. [ABSTRACT FROM AUTHOR]

Neutrophils have recently been proposed as cells with high functional plasticity and are involved in the pathogenesis of infections, malignancy, and autoimmune diseases. However, less is known about the role of neutrophil in humoral response. In this study, we examined the importance of neutrophils and the neutrophil-derived DAMP protein, MRP14, in antibody production. Splenic neutrophils and MRP14 that are present in the splenic peri-MZ region have a close contact with MZ B cells and promote their differentiation into plasma cells. Using neutrophil-depleting mice and an MRP14-blocking compound, we showed that the presence of neutrophil and MRP14 is required for class switch, plasma cell maintenance, and antibody production in the spleen. We found that MRP14 could also be produced by neutrophils in the bone marrow and support the maintenance of bone marrow plasma cells. MRP14 binding could enhance the effect of the BAFF signal and protect primary multiple myeloma cells from doxorubicin-induced apoptosis. Our data demonstrate the effects of neutrophils on neighboring B cells and plasma cells, which provides new insights into the connection between neutrophil and humoral responses. [ABSTRACT FROM AUTHOR]

Spatial heterogeneity of soil microbes introduces great uncertainty to our understanding of microbe-mediated soil carbon cycling, yet was few studied on sloping lands. Along a steep-slope grassland (35°) on the Chinese Loess Plateau, soils of 0–10 cm were sampled in 2016 at three slope positions (upper, middle and bottom) to determine microbial community composition (by Illumina Hiseq sequencing) and function (enzymes involved in carbon cycling, the in situ soil respiration and temperature sensitivity). The bacterial alpha-diversity were greater at middle- and bottom- than at upper slope position, while fungal alpha-diversity varied little across slope positions. The bacterial phylum Proteobacteria was 9.7% and 19.4% lower but Acidobacteria was 36.5% and 41.3% greater at bottom- than at upper- and middle- slope positions. The fungal community transitioned from being Basidiomycota-dominant (relative abundance of 46.8%) at upper slope position to Zygomycota-dominant (relative abundance of 36.5%) at bottom slope position. The β- d -glucosidase activity generally declined down the slope while β- d -xylosidase and cellobiohydrolase activities hiked at middle slope position. All the enzyme activities were suppressed at bottom slope position. Soil respiration increased by 49.1% ( P  < 0.05) while temperature sensitivity decreased by 13.2% ( P  < 0.05) down the slope. Both bacterial richness (OTU) and diversity (Shannon diversity index) positively correlated with soil respiration. The copiotrophic groups (Acidobacteria and Zygomycota) negatively and oligotrophic groups (Proteobacteria and Basidiomycota) positively correlated with temperature sensitivity of soil respiration. Our findings revealed divergent responses of soil bacterial and fungal communities along the slope and highlighted the importance of microbial information in predicting the spatial variability of soil respiration in hillslope ecosystems. [ABSTRACT FROM AUTHOR]

The spatial heterogeneity of soil respiration and its temperature sensitivity pose a great challenge to accurately estimate the carbon flux in global carbon cycling, which has primarily been researched in flatlands versus hillslope ecosystems. On an eroded slope (35°) of the semiarid Loess Plateau, soil respiration, soil moisture and soil temperature were measured in situ at upper and lower slope positions in triplicate from 2014 until 2016, and the soil biochemical and microbial properties were determined. The results showed that soil respiration was significantly greater (by 44.2%) at the lower slope position (2.6 μmol m–2 s–1) than at the upper slope position, as were soil moisture, carbon, nitrogen fractions and root biomass. However, the temperature sensitivity was 13.2% greater at the upper slope position than at the lower slope position (P < 0.05). The soil fungal community changed from being Basidiomycota-dominant at the upper slope position to being Zygomycota-dominant at the lower slope position, corresponding with increased β-D-glucosidase activity at the upper slope position than at the lower slope position. We concluded that soil respiration was enhanced by the greater soil moisture, root biomass, carbon and nitrogen contents at the lower slope position than at the upper slope position. Moreover, the increased soil respiration and decreased temperature sensitivity at the lower slope position were partially due to copiotrophs replacing oligotrophs. Such spatial variations along slopes must be properly accounted for when estimating the carbon budget and feedback of future climate change on hillslope ecosystems. [ABSTRACT FROM AUTHOR]

The present study evaluated drug distribution and clinical safety in treating patients with cystic craniopharyngioma (CP) with intracavitary radiotherapy using phosphorus-32 (32P) colloid. In total, 40 patients who were recently diagnosed with primary or recurrent cystic CP were enrolled into the study. Patients underwent stereotactic intracavitary therapy and were administered 32P colloid and iopamidol-300 (1:1 dilution). Head computed tomography (CT) scans were performed 2 h after surgery in order to assess drug distribution and leakage. Results obtained from the ophthalmic examination (visual acuity, visual field and fundus), enhanced head magnetic resonance imaging and/or CT scans, blood analysis, coagulation tests, electrolyte tests, pituitary hormone level analysis, and hepatic and renal function tests were compared between the 0.5, 1, 1.5 and 2 mCi groups. The 32P colloid per minute radioactive count was quantitatively measured in urine and blood samples using a CAPRAC well-type NaI γ counter at 1, 3 and 7 days post-surgery. In total, 6, 2 and 1 case(s) from the 2, 1.5 and 1 mCi groups, respectively, demonstrated heterogeneous drug distribution and intracavitary cerebrospinal fluid leakage. Furthermore, out of 24 patients, no significant differences were identified in blood analysis, blood biochemical measurements and pituitary hormone levels prior to and 7 days after surgery. Blood 32P deposition returned to normal levels within 3 days after surgery, whereas urine deposition returned to normal within 7 days after surgery. Methods utilized in the present study were advantageous in terms of convenience, speed and low cost, therefore, these techniques are suitable for continuous monitoring of patient 32P colloid deposition. [ABSTRACT FROM AUTHOR]

Knowledge of CO 2 emissions under different slope gradients and positions and its controlling factors is critical in accurately estimating CO 2 emissions and carbon cycling on the slopes of eroded regions. In this study, three east-facing plots of 100 m 2 (20 m × 5 m) with a slope gradient of 0.5° (S 0.5 ), 1° (S 1 ), and 3° (S 3 ) were established in an eroded gully of the semi-arid Loess Plateau, China. The CO 2 emission, temperature, moisture, runoff, sediment, fine root biomass and grain yield of these three plots were measured from October 2013 to September 2015 to investigate the relationship between slope gradients and soil CO 2 emissions. The results showed that the mean annual cumulative CO 2 emissions at S 1 and S 3 (731.0 ± 65.1 and 628.3 ± 74.8 g C m −2 year −1 ) were about 13.4% and 25.5% lower than that at S 0.5 (843.7 ± 84.9 g C m −2 year −1 ). The CO 2 emissions were higher at bottom slope than at upper slope, with an increase of 26.2% at S 3 , 22.9% at S 1 and 14.5% at S 0.5 , respectively. The mean soil moisture ranged from 40.8% to 44.8% water-filled pore space (WFPS) among the slope gradients, and from 35.8% to 45.6% WFPS among the slope positions. There was a significant difference in mean fine root biomass among different slope gradients (S 0.5 > S 1 > S 3, P < 0.05), but no significant difference among different slope positions. The mean soil organic carbon (SOC) ranged from 8.8 g kg −1 at S 3 to 9.9 g kg −1 at S 0.5, and that at the bottom and middle slope were higher than that at the upper slope at S 1 and S 3. Slope differentiated soil moisture content and redistribution, and the thus derived spatial differences in fine root biomass and crop yields, was the major factor influencing the soil CO 2 emissions among slope gradients and positions. Slope gradients and positions should be considered when estimating soil CO 2 emissions and carbon cycling in the complex and fragmented topography regions. [ABSTRACT FROM AUTHOR]

Nitrogen (N) fertilization has a considerable effect on food production and carbon cycling in agro-ecosystems. However, the impacts of N fertilization rates on the temperature sensitivity of soil respiration (Q10) were controversial. Five N rates (N0, N45, N90, N135, and N180) were applied to a continuous winter wheat (Triticum aestivum L.) crop on the semi-arid Loess Plateau, and the in situ soil respiration was monitored during five consecutive years from 2008 to 2013. During the growing season, the mean soil respiration rates increased with increasing N fertilization rates, peaking at 1.53 μmol m−2s−1 in the N135 treatment. A similar dynamic pattern was observed during the non-growing season, yet on average with 7.3% greater soil respiration rates than the growing season. In general for all the N fertilization treatments, the mean Q10 value during the non-growing season was significantly greater than that during the growing season. As N fertilization rates increased, the Q10 values did not change significantly in the growing season but significantly decreased in the non-growing season. Overall, N fertilization markedly influenced soil respirations and Q10 values, in particular posing distinct effects on the Q10 values between the growing and non-growing seasons. [ABSTRACT FROM AUTHOR]

A refractory high entropy alloy (RHEA) NbHfTiV was selected as the master alloy and carbon element was introduced to synthesize the novel NbHfTiVC x RHEAs (x = 0, 0.1, 0.2, 0.3), which perform outstanding strength and excellent ductility simultaneously. Phase identification, microstructure evolution, and mechanical properties were systematically analyzed. The results show that the primary MC-type carbides and nano-precipitate carbides are generated in the BCC matrix phase with the addition of carbon. The primary carbides evolve from solid spheroid (x = 0.1) to sandwich-like pattern (x = 0.2, 0.3), and grain size is significantly refined from 537 µm (x = 0) to 25 µm (x = 0.3). Compressive tests show that the yield strength increases from 958 MPa to 1115 MPa, and the fracture mechanism is changed from ductile fracture to ductile and brittle mixed fracture with carbon content increasing. Meanwhile, the atomic size mismatch and elastic mismatch of the matrix phase reduce with carbon content increasing, which could decrease the lattice distortion degree and soften the matrix phase. [Display omitted] • Carbides (FCC-MC) are generated in BCC matrix with the addition of carbon. • After adding carbon, the grain size is greatly refined from 537 to 25 µm. • Increasing carbon content release severe lattice-distorted and soften the matrix. • Yield strength of NbHfTiVC x RHEAs increase from 958 (C 0) to 1115 MPa (C 0.3). [ABSTRACT FROM AUTHOR]

In the present study, the effect of C micro-alloying on microstructure evolution and properties of metastable immiscible Cu-20Fe alloy was comprehensively investigated. Experimental results indicate that the microstructure of Cu-Fe alloy is extremely sensitive to the C content. It was found that obvious liquid-liquid phase separation (LLPS) behavior is observed in Cu-20Fe alloy after C micro-alloying, and the tendency of LLPS is enhanced with increasing C content. The calculation of ΔScc(0) suggests that C atoms preferentially pair with free Fe atoms to form new Fe (C) atomic clusters, thus resulting in the enhancement of bonding of the like-atom pairs. In addition, the quasi-binary phase diagram calculation further reveals the existence of a stable miscibility gap for C-containing alloys, and the temperature interval of miscibility gap is significantly enlarged with increasing C content. Meanwhile, the interface energy between two liquids formed by LLPS also slightly increases as C content increasing. These above reasons should be responsible for the microstructure evolution of Cu-20Fe-xC alloys. In addition, the C micro-alloying deteriorates the soft magnetic properties of Cu-Fe alloys to a certain extent, whereas improves its corresponding wear-resistance. • The microstructure evolution and solidification behavior of Cu-20Fe-xC alloys were clearly elucidated. • The calculation of ΔScc(0) indicates that C atoms preferentially pair with free Fe atoms to form new Fe(C) atomic cluster. • Phase calculation indicates that the metastable miscibility gap of Cu-20Fe alloy is stabilized by the introduction of C. • The addition of appropriate amount C enhances the wear-resistance of Cu-20Fe alloy. [ABSTRACT FROM AUTHOR]

This paper reports mesospheric bore events observed by Day/Night Band (DNB) of the Visible/Infrared Imaging Radiometer Suite (VIIRS) on the National Oceanic and Atmospheric Administration/National Aeronautics and Space Administration (NOAA/NASA) Suomi National Polar-orbiting Partnership (NPP) environmental satellite over five years (2013–2017). Two types of special mesospheric bore events were observed, enabled by the wide field of view of VIIRS: extremely wide bores (>2000 km extension perpendicular to the bore propagation direction), and those exhibiting more than 15 trailing crests and troughs. A mesospheric bore event observed simultaneously from space and ground was investigated in detail. DNB enables the preliminary global observation of mesospheric bores for the first time. DNB mesospheric bores occurred more frequently in March, April and May. Their typical lengths are between 300 km and 1200 km. The occurrence rate of bores at low latitudes is higher than that at middle latitudes. Among the 61 bore events, 39 events occurred in the tropical region (20°S–20°N). The high occurrence rate of mesospheric bores during the spring months in the tropical region coincides with the reported seasonal and latitudinal variations of mesospheric inversion layers. [ABSTRACT FROM AUTHOR]

We report the discovery of a new fluoride-arsenide bulk diluted magnetic semiconductor (Ba,K)F(Zn,Mn)As with the tetragonal ZrCuSiAs-type structure which is identical to that of the '1111' iron-based superconductors. The joint hole doping via (Ba,K) substitution &spin doping via (Zn,Mn) substitution results in ferromagnetic order with Curie temperature up to 30 K and demonstrates that the ferromagnetic interactions between the localized spins are mediated by the carriers. Muon spin relaxation measurements confirm the intrinsic nature of the long range magnetic order in the entire volume in the ferromagnetic phase. This is the first time that a diluted magnetic semiconductor with decoupled spin and charge doping is achieved in a fluoride compound. Comparing to the isostructure oxide counterpart of LaOZnSb, the fluoride DMS (Ba,K)F(Zn,Mn)As shows much improved semiconductive behavior that would be benefit for further application developments. [ABSTRACT FROM AUTHOR]