Search

Hydrological changes in groundwater coupled with earthquakes had been documented in previous studies by global researchers. Although few reports investigate multiple geochemical parameters that respond to earthquakes, trace elements received less attention, whereas they were suggested to be more sensitive to small earthquakes than the commonly used geochemical parameters. Beijing is located in the Zhangjiakou-Bohai (Zhang-Bo) seismic belt of North China, and although the occurrence of small earthquakes is frequent, the great historic earthquake in the Sanhe-Pinggu area M8 in 1679 in the adjoining southeast of Beijing gained widespread public attention. To find effective precursors that are significant for operational earthquake forecasting of the Beijing area, we carried out a one year test research project through weekly collection of groundwater samples during June 2021 to June 2022 from the seismic monitoring well of Wuliying in northwest Beijing. The 41 trace elements chemical compositions were analyzed for each sample. During the project ongoing period, the biggest earthquake with a magnitude of ML3.3 occurred in the Chaoyang District of Beijing on 3 February 2022. The content changes in these trace elements were systematically monitored before and after the earthquake. Through retrospective research, it was found that a few sensitive trace elements were anomalous to be coupled to the earthquake, including Li, Sc, Rb, Mo, Cs, Ba, W, U, Sr, Mn, Ni, and Zn. In addition to trace elements, we examined stable isotopes of hydrogen and oxygen and the existing hydrological data on groundwater level, temperature, major ions, and gases to assess the validity of geochemistry as a monitoring and predictive tool. We only found that F- (fluorine) ions and He (helium) gas had apparent shifts related to the earthquakes, while no shifts in the groundwater level were observed. Such characteristics of multiple geochemical parameters indicate that trace elements are likely to be more sensitive to crustal strain than the groundwater level and major ions. We assumed a most likely mechanism of the combination of mixing and water–rock interactions to explain the phenomenon. The probable scenario was that minor stresses caused by the earthquakes might create micro-cracks in bedrocks, thereby leading to a small volume of chemically distinct water mixing with the original water of the aquifer, and finally, the earthquake-induced rock fractures enhance the water–rock interactions, resulting in the post-seismic recovery of trace elements and δ18O value migration to the GWML. More testing works to find other sensitive sites to investigate multiple geochemical characteristics aiming at long-term to short-term earthquake prediction in the Beijing area and Zhang-Bo seismic belt are in progress.

Abstract Two-dimensional single crystal metals, in which the behavior of highly confined optical modes is intertwined with quantum phenomena, are highly sought after for next-generation technologies. Here, we report large area (>104 μm2), single crystal two-dimensional gold flakes (2DGFs) with thicknesses down to a single nanometer level, employing an atomic-level precision chemical etching approach. The decrease of the thickness down to such scales leads to the quantization of the electronic states, endowing 2DGFs with quantum-confinement-augmented optical nonlinearity, particularly leading to more than two orders of magnitude enhancement in harmonic generation compared with their thick polycrystalline counterparts. The nanometer-scale thickness and single crystal quality makes 2DGFs a promising platform for realizing plasmonic nanostructures with nanoscale optical confinement. This is demonstrated by patterning 2DGFs into nanoribbon arrays, exhibiting strongly confined near infrared plasmonic resonances with high quality factors. The developed 2DGFs provide an emerging platform for nanophotonic research and open up opportunities for applications in ultrathin plasmonic, optoelectronic and quantum devices.

This paper proposed a new one dimensional complex-valued convolution neural network (1D CVCNN) model to diagnose power switch open-circuit fault of three-phase inverter-fed PMSM system. The 1D CV convolution operation was defined and the CV rectified linear unit (ReLU) activation function was chosen. A CV backpropagation algorithm is also proposed for 1D CVCNN training. The 1D CVCNN framework model is built, where 1D inputs and all the weights between the layers are complex numbers. The Clarke transformation is used to process the three-phase current of the inverter to obtain a complex-valued signal. The non-overlapping sliding window sampling method is used to obtain CV data set. The fault classification accuracy of the 1D CVCNN has been verified by experiments, and the experimental results show that the 1D CVCNN has better feature extraction ability than any other conventional deep learning method and better robustness to noise.

To obtain an optimal range of structural parameters for dry-gas seals with good performance, this study employed advanced sensing technology to monitor and analyze the internal flow characteristics of dry-gas seals in real time. Additionally, the validity of the calculation program was verified through experimentation. Using steady-state performance parameters as evaluation indices, a calculation model with lubrication characteristics was developed. The results indicate that when there are 12 grooves, the gas film pressure distribution is uniform and has a high value. At pressures greater than 2 MPa, the opening force, leakage, and gas film stiffness change significantly due to enhanced dynamic pressure effects with high-pressure differences, which reduces the local contact forces and frictional forces. At a constant speed, decreasing the gas film thickness increases the pressure difference while increasing both the opening force and film stiffness; however, at higher rotational speeds where the gas flow becomes non-uniform, the stability of the gas film is affected, leading to increased frictional forces. When there are between 10 and 16 grooves with depths ranging from 5.0 to 6.0 μm, dynamic pressure effects caused by pressure gradients become apparent, resulting in good dry-gas sealing performance being achieved. This research provides a theoretical reference for optimizing the design of dry-gas seals, as well as their steady-state seal performance.

Abstract For around half of the pediatric B-lineage acute lymphoblastic leukemia (B-ALL) patients, the molecular mechanism of relapse remains unclear. To fill this gap in knowledge, here we characterize the chromatin accessibility landscape in pediatric relapsed B-ALL. We observe rewired accessible chromatin regions (ACRs) associated with transcription dysregulation in leukemia cells as compared with normal B-cell progenitors. We show that over a quarter of the ACRs in B-ALL are in quiescent regions with high heterogeneity among B-ALLs. We identify subtype-specific and allele-imbalanced chromatin accessibility by integrating multi-omics data. By characterizing the differential ACRs between diagnosis and relapse in B-ALL, we identify alterations in chromatin accessibility during drug treatment. Further analysis of ACRs associated with relapse free survival leads to the identification of a subgroup of B-ALL which show early relapse. These data provide an advanced and integrative portrait of the importance of chromatin accessibility alterations in tumorigenesis and drug responses.

Mass concrete is widely used in large-scale projects, including metro upper cover structures, water conservancy dams, and heavy equipment foundations, among others, necessitating the process of health monitoring in mass concrete construction. The development of reliable and simple strength-monitoring methods for mass concrete is challenging because the inner temperature of mass concrete is high and changes a lot. This study proposes a strength-monitoring approach for mass concrete using barium titanate–bismuth ferrite/polyvinylidene fluoride (BT–BFO/PVDF) nanocomposite piezoelectric sensors, wherein the new sensors are embedded as actuators and sensors in mass concrete. The stress wave generated by the BT–BFO/PVDF piezoelectric sensors is used to monitor the specimen’s strength for 28 days. The piezoelectric voltage received by the sensors in mass concrete is analyzed. The experimental results indicate that the signal received by the BT–BFO/PVDF sensors is not easily affected by the internal temperature of mass concrete compared with that of the traditional PVDF piezoelectric sensors. The signal parameters sensitive to concrete strength variation and the change trend of concrete strength are closely related to the piezoelectric voltage. Therefore, the proposed approach using BT–BFO/PVDF nanocomposite piezoelectric sensors is efficient (error < 10%) in mass concrete monitoring. Moreover, the monitoring results do not need temperature compensation. The physical meaning of the obtained strength prediction formula is proposed. An experimental system based on PVDF dynamic strain-sensing characteristics is established.

Enormous endeavors have been made to cope with microwave pollution and energy crisis. Here, porous nitrogen-doped C/TiO2 composites with absorption/shielding/supercapacitor functions were derived from MXene/polyaniline. It was discovered that KOH acted as porogen and had an etching–bridging–reaction effect during the activation process. As a microwave absorber, the composite/paraffin with a filler loading of 16 wt% reaches a minimum reflection loss of −52.8 dB and an effective absorption bandwidth of 4.72 GHz. Moreover, microwave absorption can be maintained within 45 days in air. Compared with untreated MXene, the absorber shows long-term functional stability in an oxygen-containing environment. As for electromagnetic interference shielding, the composite/paraffin at a filler loading of 50 wt% achieves 30.5 dB from 8.0 to 12.4 GHz. Additionally, the heterostructure delivers a desirable specific capacitance of 1,096.3 F g−1 at 0.5 A g−1. The trifunctional characteristics enrich the application trials of MXene derivatives and satisfy the strong need for versatile materials.

Ground-level ozone (O3) pollution has been a severe environmental and health problem for decades. The importance of biogenic volatile organic compounds (BVOCs) in the formation of tropospheric photochemistry O3 has been highlighted, especially in areas of rapid urbanization. We conducted simultaneous measurements of trace gases, including NO, NOX, O3, and BVOCs (i.e., isoprene and α-pinene), in the urban and rural forest areas of Beijing to determine the relationships between them. The results highlight the differences between the urban and rural forest areas of Beijing in terms of ambient air concentrations of BVOCs and O3, and the interrelationships between BVOCs, NOX, and ozone were quantified. Moreover, the isoprene concentration was found to be higher in the atmosphere of the urban site than of the rural site, which had higher α-pinene concentrations and higher O3 concentrations. The NOX concentration was higher at the urban site than at the rural site, and there was a significant exponential relationship between NOX and O3 at the urban site, indicating that the impact of NOx on O3 at the urban site was greater than that at the rural site. The O3 concentration increased with rising isoprene and α-pinene in both sites. In the case of substantially increased BVOC concentrations, declining NOX concentrations strongly promote the formation of O3. Consideration should be given to planting tree species with low-BVOC emissions, as they are crucial for mitigating O3 pollution in urban areas. Additionally, the relationships between BVOCs, NOX, and O3 should be considered in policymaking related to O3 control.

The energy inside the Earth can not only be released outward through earthquakes and volcanoes but also can be used by humans in the form of geothermal energy. Is there a correlation between different forms of energy release? In this contribution, we perform detailed seismic and geothermal research in the Beijing area. The results show that the geothermal resources in Beijing belong to typical medium-low temperature geothermal resources of the sedimentary basin, and some areas are controlled by deep fault activities (e.g., Xiji geothermal well (No. 17)). The heat sources are upper mantle heat, radioactive heat in granite, and residual heat from magma cooling. The high overlap of earthquakes and geothermal field locations and the positive correlation between the injection water and earthquakes indicate that the exploitation and injection water will promote the release of the earth’s energy. The energy releases are partitioned into multiple microearthquakes, avoiding damaging earthquakes (ML ≥ 5) due to excessive energy accumulation. Therefore, the exploitation of geothermal resources may be one way to reduce destructive earthquakes. Furthermore, the use of geothermal resources can also reduce the burning of fossil energy, which is of great significance in dealing with global warming.

The genomic landscape of pediatric acute myeloid leukemia (AML) has mostly been characterised for Western populations. Here, the authors identify potential driver alterations in Chinese pediatric AML, which differ from Western populations, and propose a prognostic risk classification model.

A suspension flux internal model control method is proposed to address the problem of the strong coupling of a single-winding bearingless flux-switching permanent magnet motor leading to a significant ripple of the rotor radial displacement. Firstly, based on air-gap magnetic field modulation theory, the stator flux equation considering rotor dynamic eccentricity is established to reveal the relationship between the eccentric rotor and the magnetic field. Secondly, according to the dynamic characteristics of the motor and the variation law of the air-gap magnetic field, the suspension-plane flux is substituted into the rotor dynamic model, and the suspension flux-dynamics internal model and corresponding output are constructed, respectively. Finally, a complete control strategy is established, and the rotor is stably suspended by PWM control. The simulation and experimental results show that the proposed method has better steady-state and dynamic performance than traditional PID control, and the maximum radial displacement ripples of the rotor are reduced by 53% and 50% in steady-state and dynamic operation.

Plastic materials have revolutionized modern life, particularly in the domain of food packaging, owing to their versatility, lightweight nature, and ease of processing. However, the environmental ramifications of non-degradable plastics have raised concerns. Polylactic acid (PLA), derived from renewable sources, represents a sustainable alternative due to its biodegradability and exceptional barrier, mechanical, and safety properties. Nevertheless, the high UV transmittance of PLA limits its use for photosensitive food and pharmaceutical packaging, where UV radiation can lead to nutritional loss and spoilage. Various methods have been explored to enhance the UV-blocking capabilities of PLA, including the integration of inorganic nanoparticles and surface coatings. Despite advancements, these approaches often compromise the inherent transparency of PLA. Incorporating large conjugated groups can maintain transparency but introduces additional challenges. This paper reviews modification methods to enhance PLA’s UV-barrier properties and anticipates its expanded utility in food and drug packaging, promoting UV resistance and diversifying PLA’s applications.

Abstract. T cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy often associated with poor outcomes. To identify high-risk factors and potential actionable targets for T-ALL, we perform integrated genomic and transcriptomic analyses on samples from 165 Chinese pediatric and adult T-ALL patients, of whom 85% have outcome information. The genomic mutation landscape of this Chinese cohort is very similar to the Western cohort published previously, except that the rate of NOTCH1 mutations is significant lower in the Chinese T-ALL patients. Among 47 recurrently mutated genes in 7 functional categories, we identify RAS pathway and PTEN mutations as poor survival factors for non-TAL and TAL subtypes, respectively. Mutations in the PI3K pathway are mutually exclusive with mutations in the RAS and NOTCH1 pathways as well as transcription factors. Further analysis demonstrates that approximately 43% of the high-risk patients harbor at least one potential actionable alteration identified in this study, and T-ALLs with RAS pathway mutations are hypersensitive to MEKi in vitro and in vivo. Thus, our integrated genomic analyses not only systematically identify high-risk factors but suggest that these high-risk factors are promising targets for T-ALL therapies.

BackgroundThe COVID-19 pandemic has seriously increased depression prevalence among the public, including Chinese college students. However, many exercise cannot be performed as usual under the stay-at-home order. This study was a 12-week three-arm randomized controlled trial using the intention-to-treat principle, aiming to explore and compare the feasibility and effect of individual-based personalized aerobic-exercise and resistance-training prescriptions on depressive symptoms in college students, and conclude with some recommendations for individual-based exercise prescriptions.MethodsEighty-six college students with depressive symptoms were randomized into aerobic-exercise (AE), resistance-training (RT), and wait-list control (WLC) groups. Participants in two experimental groups received 12-week personalized AE and RT prescriptions on their individual situations, respectively. No intervention was implemented on participants in the WLC group. Depressive symptoms and physical activity (PA) were measured by Zung Self-Rating Depression Scale (SDS) and International Physical Activity Questionnaire-Short Form (IPAQ-SF), respectively. All data were collected at the baseline, 4, 8, and 12 weeks, and 4-week post-intervention.ResultsAt 12 weeks, 72.09% of depressive participants improved to “normal.” Participants exhibited a statistical reduction in SDS in all 3 groups (p < 0.05) at 12 weeks compared to baseline. Follow-up assessments showed no significant increase in SDS at 4-week post-intervention compared to 12 weeks (p > 0.05). The independent t-test revealed significantly lower SDS in AE and RT group than in WLC group (pAE < 0.001 and pRT < 0.05) at 4, 8, and 12 weeks, and 4-week post-intervention. Furthermore, the PA of participants (including total PA and intensities) in both experimental groups represented a significant improvement at 4-week post-intervention compared to baseline (p < 0.05), while no differences were observed in the PA of participants in the WLC group (p > 0.05).ConclusionPersonalized exercise prescriptions have good feasibility as they can increase adherence to intervention and reduce serious adverse events. Besides, individual-based personalized aerobic-exercise and resistance-training prescriptions result in a similar effect in relieving depressive symptoms and improving physical activity in college students. The individual-based exercise programs performed in 45- to 60- min with progressive moderate-to-vigorous intensity, 3 times/week for at least 12 weeks, may reduce depressive symptoms in college students during the COVID-19.

Trees growing on paved lands endure many environmental stresses in the urban environment. However, the morphological and physiological mechanisms underlying tree adaptation to pavement in the field are less known. In this study, we investigated 40 sites where Ginkgo biloba and Platanus orientalis grow on adjacent pairs of paved and vegetated plots in parks and roadsides in Beijing, China. Relative to the vegetated land, the mean increments in the diameter at breast height and height in the paved land were significantly decreased by 44.5% and 31.9% for G. biloba and 31.7% and 60.1% for P. orientalis, respectively. These decreases are related to both the decrease in assimilation products due to the reductions in leaf area, leaf total nitrogen content, and chlorophyll content and the increase in energy cost due to the synthesis of more soluble sugar and proline for mitigating stress. The increase in leaf soluble sugar content, proline content, and δ13C indicated that trees could adapt to the paved land through the regulation of osmotic balance and the enhancement of water-use efficiency. Piecewise structural equation models showed that trees growing on the paved land are stressed by compounding impacts of the leaf morphological and physiological changes. Therefore, it is critical to explore the complex response of plant morphological and physiological traits to the pavement-induced stress for improving tree health in urban greening.

The Beijing and Zhangjiakou-Bohai Fault Zone is a group of NW-W orderly active fault zones with high seismic activity and abundant geothermal resources since the Cenozoic. Many violent earthquakes occurred here, where it was an important area for earthquake monitoring and research. In order to explore the temporal and spatial variation characteristics of gas geochemistry in the Zhangjiakou-Bohai Fault Zone of the capital circle, this study cited the previous two-stage survey data of 23 geothermal hot springs in the west and east of the Zhangjiakou-Bohai Fault Zone of the capital circle in 2013 and 2018. In order to fill the gap in hot spring gas geochemistry in Beijing (the middle of the Zhangjiakou-Bohai Fault Zone), 21 emergent gas samples from hot springs were collected after many field surveys from October 2020 to November 2021. The test results of 44 gas samples with chemical compositions and isotope changes of helium, neon, and carbon showed that: (1) The helium isotope ratio (3He/4He (Rc/Ra)) of hot spring gases in the Zhangjiakou-Bohai Fault Zone ranged between 0.03 and 2.86Ra (Ra = air, 3He/4He = 1.39 × 10−6), and the calculated maximum proportion of mantle-derived helium was up to 35.4%. It was revealed that although the geological fluid in the fault zone mainly came from crustal source, the mantle-derived helium was still considerable. The hot spring gases in Beijing (the middle of the Zhangjiakou-Bohai Fault Zone) were mainly composed of nitrogen, whose concentration was more than 69%, featuring a low CO2 concentration of 0–6.1% and a δ13CCO2 value ranging from −19‰ to −9.6‰ (vs.PDB) and showing the mixing characteristics of organic sediments and mantle sources. (2) The upwelling release of mantle-derived materials in Zhangjiakou-Bohai Fault Zone shared a good corresponding relationship with regional seismicity, which could promote the inoculation and occurrence of regional earthquakes. In the peak area, the transition zone from the western mountainous area of the Zhangjiakou-Bohai Fault Zone to the plain showed that more mantle-derived materials upwelled, and more deep fluid upwelled. The comparative analysis of regional seismicity showed that deep fluid played an important role in controlling regional seismicity in the area with relatively strong upwelling of deep fluid in the Zhangjiakou-Bohai Fault Zone.

Flexible supercapacitors are demanded for energy storage of wearable electronics. In this paper, a simple strategy for preparing flexible carbon fibers (CFs) with good energy storage capacity using a mixed acid treatment process is reported. When the volume ratio of concentrated sulfuric acid to concentrated nitric acid is 3:1, the carbon fiber electrodes have the best electrochemical performance with a high capacitance of 27.83 F g−1 at 15 mA g−1 and extremely high capacitance retention of 79.9% after 500 cycles at 100 mA g−1. Furthermore, their energy density can reach 3.86 Wh kg−1 with a power density of 7.5 W kg−1. Such an excellent electrochemical performance of carbon fiber electrodes is attributed to their surface rich oxygen-containing functional groups, rough surface, and a certain number of graphene quantum dots (GQDs). Importantly, the all-solid-state flexible supercapacitor performs excellent bending stability performance with a capacitance retention of almost 100% after 500 times of bending at 180°, showing good prospects and applications in the field of flexible energy storage devices.

Abstract Background Epigenome-wide association studies (EWAS), which seek the association between epigenetic marks and an outcome or exposure, involve multiple hypothesis testing. False discovery rate (FDR) control has been widely used for multiple testing correction. However, traditional FDR control methods do not use auxiliary covariates, and they could be less powerful if the covariates could inform the likelihood of the null hypothesis. Recently, many covariate-adaptive FDR control methods have been developed, but application of these methods to EWAS data has not yet been explored. It is not clear whether these methods can significantly improve detection power, and if so, which covariates are more relevant for EWAS data. Results In this study, we evaluate the performance of five covariate-adaptive FDR control methods with EWAS-related covariates using simulated as well as real EWAS datasets. We develop an omnibus test to assess the informativeness of the covariates. We find that statistical covariates are generally more informative than biological covariates, and the covariates of methylation mean and variance are almost universally informative. In contrast, the informativeness of biological covariates depends on specific datasets. We show that the independent hypothesis weighting (IHW) and covariate adaptive multiple testing (CAMT) method are overall more powerful, especially for sparse signals, and could improve the detection power by a median of 25% and 68% on real datasets, compared to the ST procedure. We further validate the findings in various biological contexts. Conclusions Covariate-adaptive FDR control methods with informative covariates can significantly increase the detection power for EWAS. For sparse signals, IHW and CAMT are recommended.

GATA2 is a transcription factor that is critical for the generation and survival of hematopoietic stem cells (HSCs). It also plays an important role in the regulation of myeloid differentiation. Accordingly, GATA2 expression is restricted to HSCs and hematopoietic progenitors as well as early erythroid cells and megakaryocytic cells. Here we identified aberrant GATA2 expression in B-cell acute lymphoblastic leukemia (B-ALL) by analyzing transcriptome sequencing data obtained from St. Jude Cloud. Differentially expressed genes upon GATA2 activation showed significantly myeloid-like transcription signature. Further analysis identified several tumor-associated genes as targets of GATA2 activation including BAG3 and EPOR. In addition, the correlation between KMT2A-USP2 fusion and GATA2 activation not only indicates a potential trans-activating mechanism of GATA2 but also suggests that GATA2 is a target of KMT2A-USP2. Furthermore, by integrating whole-genome and transcriptome sequencing data, we showed that GATA2 is also cis activated. A somatic focal deletion located in the GATA2 neighborhood that disrupts the boundaries of topologically associating domains was identified in one B-ALL patient with GATA2 activation. These evidences support the hypothesis that GATA2 could be involved in leukemogenesis of B-ALL and can be transcriptionally activated through multiple mechanisms. The findings of aberrant activation of GATA2 and its molecular function extend our understanding of transcriptional factor dysregulation in B-ALL.

The modular heat storage wall is a new type of solar greenhouse wall structure, which has the advantages of fast construction and good heat storage ability. This study provides data reference and practical value for producing modular heat storage wall in the construction of a solar greenhouse. In this paper, we used different heat storage materials to construct the modular wall. In the winter thermal environment test, soil module solar greenhouse (SG) and stone module solar greenhouse (PG) were controlled against each other in two greenhouses. The test results for 28 consecutive days (31 January 2021 9:00 to 28 February 2021 9:00) showed that both greenhouses could effectively increase the temperature in greenhouse by 10–12 °C. The average temperature of SG was 0.86 °C lower than that of PG during the daytime (09:00–17:00) and 0.44 °C higher than that of PG during the nighttime (17:00–09:00). Under typical sunny conditions, the average temperature differences between the inlet and outlet of SG in the heat storage and exothermic stage was less than that of PG, and the relative humidity difference was greater than that of PG. This indicated that SG had a better performance of heat preservation than PG and could raise the nighttime temperature rapidly. Under the condition of a typical cloudy day, the average temperature difference between the inlet and outlet was SG < PG and the relative humidity difference was SG > PG in the exothermic stage, which was consistent with the conclusion of sunny days. In the storage and exothermic stages of typical sunny days and cloudy days, the total heat exchange of SG was 464.87, 110.44 and 54.82 MJ and the total heat exchange of PG was 264.16, 61.60 and 46.89 MJ, respectively. Moreover, the heat storage and release of SG were more than that of PG in all stages. In summary, the thermal performance of the modular heat storage wall heliogreenhouse could meet the growth of tomato crop, in which the heat transfer performance of SG was optimum.

An increasing number of studies have focused on the response and adaptation of plants to urbanization by comparing differences in leaf functional traits between urban and rural sites. However, considerable uncertainties remain because differences in land-use type have not frequently been taken into account when assessing the effect of urbanization on leaf traits. In this study, we sampled the needles of Chinese pine (Pinus tabuliformis Carr.) in areas with three land-use types (roadsides, parks, and neighborhoods) along an urban–rural gradient in Beijing, China to determine the effect of urbanization on leaf functional traits. There were significant differences in the values of leaf functional traits between the needles of the current and previous year and across land-use types. Pines growing on roadsides had leaves with smaller length, width, and area, as well as lower stomatal density, compared with those growing in parks and neighborhoods. This implies that on roadsides, plant capacity to acquire resources (e.g., light and carbon dioxide) was degraded. Stomatal density, leaf width, and leaf P concentration increased with increasing distance from the city center, while leaf K concentration decreased with increasing distance from the city center. Importantly, there were significant differences in the urban–rural gradient of leaf functional traits between leaves of different ages, and across land-use types. Leaf age was the most important factor influencing leaf nutrient traits, while land-use type was the most important factor influencing leaf morphological traits in urban environments. Thus, considering the effects of the plant characteristic and land-use type on traits is important for assessing the urban–rural gradients of plant functional traits.

Carbon fiber (CF) reinforced composites are widely used due to their excellent properties. However, the smooth surface and few functional groups of CFs can lead to fiber fractures and pullout, which reduce the service life of the composites. The overall performance of composites can be improved by growing carbon nanotubes (CNTs) on the CF surface. Before this, CF surface should be modified to enhance the loading amount of catalyst particles and thus make the CNTs more uniform. In this paper, CNTs were grown on a CF surface by one-step chemical vapor deposition to prepare multi-scale CNTs/CF reinforcements, and the effects of different methods on the CF surface modification were explored. After setting four intensities of electrochemical anodic oxidation, i.e., 50 C/g, 100 C/g, 150 C/g and 200 C/g, it was found that the distribution and quantity of CNTs were improved under both the 100 C/g and 150 C/g conditions. Considering the influence of electrical intensity on the (002) interplanar spacing of CFs, which affects the mechanical properties of the samples, 100 C/g was finally selected as the optimal electrochemical treatment intensity. This finding provides a reference for continuous and large-scale modification of CF surfaces to prepare CNTs/CF multi-scale reinforcements.

A 3D passive micromixer with particles of stochastic motion is presented. 3D printing technology and computer numerical control milling technology are employed to manufacture the channel mold with the material of high impact polystyrene. Furthermore, a limonene dissolution method is utilized to dissolve the channel mold. The experimental results demonstrated that the mixing efficiency of the micromixer first increases and then decreases with the increase in the number of particles. Specifically, the mixing efficiency of the micromixer with two cube particles reaches 0.95 with the optimal particle size of 1.5 × 1.5 × 1.5 mm3. In addition, the larger the flow velocity is, the higher the mixing efficiency of the micromixer is. When the flow velocity reaches 1.0 ml/min, the mixing efficiency of the micromixer exceeds 0.9. Compared with the previous micromixers, a 3D passive micromixer with particles of stochastic motion has the advantages of simple manufacturing and no external power. This article is of great significance to the research of micromixers.

A method for manufacturing glass channels with a three-dimensional microstructure array via the micromilling technique is proposed. The three-dimensional microstructure array includes microcolumns, microcones, and microspheres. Then, the glass chip with the three-dimensional microstructure array is bonded with a polydimethylsiloxane chip. To obtain the optimum structure, the experiment of the contact angle is implemented. The results demonstrate that among the three different shapes, the contact angle of the microcolumn array is the largest with a value of 74.3° ± 2.4°. Compared with the other two structures, the microcolumn array is more helpful for continuous liquid mixing. Furthermore, with the increase in the array depth, the contact angle becomes small with the minimum contact angle of 37.9° ± 1.4°. Meanwhile, with the increase in the microcolumn diameter and array spacing, the contact angle becomes large with the maximum contact angle of 83.9° ± 1.4°. In addition, a mixing experiment is developed to verify the practicability of the chip. Compared to other processing methods, this method obtains the advantages of high efficiency and flexibility.

An increasing number of studies have found differences in the diversity of plant functional traits between urban and rural sites as a result of urbanization. However, the results remain inconsistent. In this study, we measured morphological and nutrient traits of 11 common woody plants along a continuous urban–rural gradient in Beijing, China. Leaf size (e.g., length, width, and area), specific leaf area, and leaf nitrogen and potassium contents decreased gradually and significantly along the urban–rural gradient, indicating that urbanization can enhance the capacity of plants to acquire resources for growth and production. Furthermore, soil nutrients and air temperature decreased along the urban–rural gradient, while air relative humidity increased. A structural equation model showed that these alterations in physical factors attributable to urbanization contributed directly or indirectly to changes in leaf functional traits, implying that changes in soil nutrients and micro-climate induced by urbanization may affect plant growth and production because of the improvement in resource acquisition capacity.

The joint planning of spare parts and maintenance workers in a multiple echelon inventory system with lateral and cross-echelon transshipment can reduce the total cost of the system. However, partial pooling is not extensively considered in the joint optimization problem of maintenance resources. In this paper, the objective is to determine the optimal inventory of spare parts and the number of maintenance workers to minimize the total cost of the system considering partial pooling. First, a greedy heuristic is used to obtain the initial inventory. Then, the cat swarm optimization algorithm is formulated to produce nearly optimal results, which can solve larger instances with a faster computation time. Furthermore, a maintenance system with 4 local warehouses, 3 central warehouses and 1 plant serving 5 machine groups is analyzed, in which each machine consists of 5 key components that can breakdown independently. The results verify the effectiveness of the proposed optimization approach. Finally, the total cost for different resource provision scenarios, failure rates and system parameters are discussed.

A magnetic dispersive solid phase extraction method coupled with high-performance liquid chromatography was proposed for the simultaneous separation and determination of paraquat (PQ) and diquat (DQ) in human plasma and urine samples. Based on the reduction of PQ and DQ to a blue radical and yellow-green radical by sodium dithionite in an alkaline medium, a fast colorimetric method was also developed for the fast detection of PQ or DQ. In this paper, CoFe2O4@SiO2 magnetic nanoparticles were used as the adsorbent for the magnetic dispersive solid phase extraction of paraquat and diquat, and these two analytes were found to be eluted directly from the adsorbent by NaOH solution. The main factors affecting the extraction efficiency including amount of extractant, extraction time, sample volume, sample solution pH, and elution volume were optimized. Under the optimized experimental conditions, the calibration curve was linear at a concentration range of 28.5–570.2 μg/L, and the correlation coefficient of paraquat and diquat was 0.9986 and 0.9980, respectively. The limits of detection of paraquat and diquat were 4.5 μg/L and 4.3 μg/L. The proposed MSPE-HPLC method was successfully applied to the detection of the paraquat and diquat in human plasma and urine with satisfied recoveries of PQ and DQ in the range of 87.5%–98.7%.

The paper presents a square-root-extended complex Kalman filter (SRECKF) by decomposing covariance matrix with its square-root forms to improve stability of the filter for estimating complex number. αβ transformation is used to map three-phase instantaneous voltages in the abc phases into instantaneous voltages on the αβ axes, and a non-linear state equation and observation equation of the three-phase voltages are built by introducing a complex vector and defining state variables. Positive symmetrical component, negative symmetrical components, and frequency of the three-phase voltages are estimated using traditional extended complex Kalman filter (ECKF), the estimation results show that the method proposed here are superior to traditional extended complex Kalman filter on estimation accuracy and convergence rate.

The spatial heterogeneity of plant diversity at the neighborhood scale has less been understood, although it is very important for the planning and management of neighborhood landscape. In this case study of Beijing, we conducted intensive investigations of the plant diversity in different neighborhoods along a rural–urban gradient. The results showed that the mean numbers of plant species per neighborhood were 30.5 for trees, 18.8 for shrubs, and 31.9 for herbs, respectively. There were significant logarithmic relationships between the numbers of species and patch area, indicating that larger patches within neighborhoods could harbor more plant species. Hierarchical linear modeling showed that the variations in plant diversity within neighborhoods were higher than those between neighborhoods. The number of species increased logistically with both the number of patches within neighborhoods and the number of neighborhoods, suggesting that it is important to sample a sufficient number of patches within neighborhoods, as well as a sufficient number of neighborhoods in order to sample 90% of the plant species during the investigation of plant diversity in urban neighborhoods. So the hierarchical design of sampling should be recommended for investigating plant diversity in urban areas.

The increase in bioinformatics resources such as tools/scripts and databases poses a great challenge for users seeking to construct interactive and reproducible biological data analysis applications. Here, we propose an open-source, comprehensive, flexible R package named BioInstaller that consists of the R functions, Shiny application, the HTTP representational state transfer application programming interfaces, and a docker image. BioInstaller can be used to collect, manage and share various types of bioinformatics resources and perform interactive and reproducible data analyses based on the extendible Shiny application with Tom’s Obvious, Minimal Language and SQLite format databases. The source code of BioInstaller is freely available at our lab website, http://bioinfo.rjh.com.cn/labs/jhuang/tools/bioinstaller, the popular package host GitHub, https://github.com/JhuangLab/BioInstaller, and the Comprehensive R Archive Network, https://CRAN.R-project.org/package=BioInstaller. In addition, a docker image can be downloaded from DockerHub (https://hub.docker.com/r/bioinstaller/bioinstaller).

The SnS _2 /MoS _2 nanospheres (NPs) were prepared by a facile hydrothermal route, and microstructure and morphology were investigated by SEM, TEM, XRD and BET. The SnS _2 /MoS _2 NPs exhibited the excellent adsorption properties for organic dyes, and the maximum adsorption capacity of SnS _2 /MoS _2 to Rhodamine B (RhB) is 125 mg g ^−1 at room temperature. The adsorption process is well fit by the pseudo-second-order adsorption model and Langmuir isotherm model. Moreover, SnS _2 /MoS _2 NPs has outstanding adsorption capacity for both cations and anions organic dyes, and the maximum adsorption capacity for methylene blue (MB), crystal violet (CV) and malachite green (MG) were 202, 165 and 175 mg g ^−1 respectively. It is attribute to the high specific surface area (101.06 m ^2 g ^−1 ) and small mesopores (3.23 nm) provide numerous adsorption active sites for adsorption of organic dyes. The reusability experiment demonstrated the SnS _2 /MnS _2 NPs could be reused for 5 times. The result show that the SnS _2 /MoS _2 NPs is a potential adsorbent for removal of organic dyes from wastewater.

BACKGROUND: Phosphorus (P) is an essential macronutrient for plant growth and development. Several genes involved in phosphorus deficiency stress have been identified in various plant species. However, a whole genome understanding of the molecular mechanisms involved in plant adaptations to low P remains elusive, and there is particularly little information on the genetic basis of these acclimations in coniferous trees. Masson pine (Pinus massoniana) is grown mainly in the tropical and subtropical regions in China, many of which are severely lacking in inorganic phosphate (Pi). In previous work, we described an elite P. massoniana genotype demonstrating a high tolerance to Pi-deficiency. METHODOLOGY/PRINCIPAL FINDINGS: To further investigate the mechanism of tolerance to low P, RNA-seq was performed to give an idea of extent of expression from the two mixed libraries, and microarray whose probes were designed based on the unigenes obtained from RNA-seq was used to elucidate the global gene expression profiles for the long-term phosphorus starvation. A total of 70,896 unigenes with lengths ranging from 201 to 20,490 bp were assembled from 112,108,862 high quality reads derived from RNA-Seq libraries. We identified 1,396 and 943 transcripts that were differentially regulated (P