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Groundwater in the Yinchuan Plain (China) is a critical domestic resource that is also used for agricultural irrigation and to maintain ecological environments, among other purposes. Recent research has shown that ineffective planning of water resources, along with large-scale groundwater pumping (mining) has led to ecological problems. To further analyze the characteristics of the regional groundwater flow patterns, and guide the development and utilization of water resources, potentiometric, hydrochemical, and isotopic data were collected along a 60-km transect that crosses the middle Yinchuan Plain. The data were used to develop a two-dimensional conceptual model of the sources, flow patterns, and geochemical evolution of groundwater from the Helan Mountains in the west across the Yellow River in the east. An important component of the model is that in the process of groundwater flow from west to east, the flow direction changes due to the influence of a thick fine-grained sandy-clay unit and long-term groundwater pumping. Local lakes and the shallow groundwater system are recharged by water from the Yellow River. Geochemically, water within the proluvial deposits exhibits relatively low concentrations of total dissolved solids. Further east, the water gradually becomes brackish. The geochemical composition of the shallow groundwater beneath the fluviolacustrine plain west of the Yellow River is also controlled by evaporation, precipitation and cation exchange processes. In other areas, groundwater chemistry is mainly controlled by water–rock interactions and cation exchange. This study enhances understanding of groundwater flow in the region, and provides information critical to water resources development and management.

In this work, metal–organic frameworks (MOFs) are utilized as effective ECL coreactant accelerator to enhance the ECL responses of N-(aminobutyl)-N-(ethylisoluminol) (ABEI). Zn-based MOFs (MOF-Zn-1) were prepared by chelating Zn ions with melamine and thiophenedicarboxylic acid (TPDA), which observably accelerated the electrocatalytic oxidation of tripropylamine (TPA). Then, ABEI-MOF-Zn-1 as a high-performance ECL emitter was synthesized via an amide reaction between ABEI and mercaptopropionic acid (MPA) modified MOF-Zn-1. Strikingly, the ABEI-MOF-Zn-1 showed the 18-fold increase in the ECL signals relative to pure ABEI by using TPA as a coreactant. Moreover, ferrocene (Fc) as a quencher was first linked with capture DNA (cDNA), and then used to modify the ABEI-MOF-Zn-1, thereby constructing a label-free ECL biosensor. After the linkage between chloramphenicol (CAP) and aptamer DNA (aptDNA), the ECL response was definitely recovered by releasing L-DNA from double-stranded DNA (dsDNA, hybridization of aptDNA and L-DNA). The resultant sensor showed a wide linear range of 1.00 nM–0.10 mM (R2 = 0.99) and a low limit of detection (LOD) down to 0.11 nM for detecting CAP. This work developed a novel pattern to design an efficient ECL enhanced emitter, coupled by expanding its potential applications in clinical diagnosis.

Development of ultra-sensitive and high specific aptasensors is important for early diagnosis of prostate cancer. Herein, ultrasensitive detection of prostate specific antigen (PSA) aptasensor was realized based on the “on-off-on” model via fluorescence (FL) covalent energy transfer between g-C3N4 quantum dot (g-CNQDs) and palladium triangular plates (Pd TPs). Specifically, the Pd TPs were primarily linked with PSA aptamer (PA) as the reporter probe, followed by attaching them onto the g-CNQDs surfaces, causing the highly enlarged FL quenching rate (ca. 75%). After the introduction of PSA, the FL intensities recovered again because of the distinctively stronger affinity of PA to PSA than that of g-CNQDs. The bond of pyridine N with Pd was identified as efficient energy transfer pathway through the X-ray photoelectron spectroscopy (XPS) and FL measurements. The surface plasmon resonance (SPR) experiments certified the remarkably different affinity of PA towards g-CNQDs and PSA. The as-constructed FL aptasensor can accurately quantify PSA with wide linear range of 10 pg mL−1-50 ng mL−1 and ultra-low limit of detection (LOD, 4.2 pg mL−1), indicating the promising applications in clinical assay and biological detection.

The transplacental transfer of maternal antibodies to the fetus is a critical mechanism for infant protection and perinatal disease. Hemolytic disease of the fetus and newborn (HDFN) is a representative fetal disease caused by transplacental transfer of maternal IgG antibodies. However, it is unclear whether placental-related miRNAs are expressed in Rh-HDFN. Through the investigation of the miR-181a-5p and miR-125b-2-3p levels in maternal plasma using qPCR, we found that both miR-181a-5p and miR-125b-2-3p were highly expressed in maternal plasma of newborns with Rh-HDFN compared with healthy controls, indicating the potential roles of these two miRNAs in Rh-HDFN. To demonstrate whether dysregulation of miR-125b-2-3p and miR-181a-5p contributes to Rh-HDFN development, we analyze the placental miRNA-/mRNA sequencing data (GSE73714) using weighted gene coexpression network analysis (WGCNA), miRNA target predictive databases, and DAVID (Database for Annotation, Visualization, and Integrated Discovery). The results showed that miR-125b-2-3p and miR-181a-5p could regulate several biological processes including cytoplasmic microtubule organization and angiogenesis. Moreover, core promoter sequence-specific DNA binding and protein binding were highly enriched molecular functions, indicating the potential roles of transcriptional regulation. Further pathway enrichment showed that miR-181a-5p and miR-125b-2-3p could regulate several biological pathways that were closely related to placental function, including the FoxO signaling pathway, focal adhesion, mTOR signaling pathway, and central carbon metabolism in cancer. In conclusion, the present results first revealed miRNA expression in the maternal circulation of newborns with Rh-HDFN, which could be caused by dysfunction of the placenta.

To investigate the prevalence of 11 thoracic vertebrae (TVs), four lumbar vertebrae (LVs) and six LVs among asymptomatic Chinese volunteers, and the influence of spine variations on the global spinal sagittal parameters.A total of 389 asymptomatic Chinese volunteers were recruited. Each subject underwent a full-spine X-ray examination with measurement of global spinal sagittal parameters. The radiographs were examined by a spine surgeon and a radiologist to determine the variation in the number of vertebrae. These parameters were used to compare individuals with five LVs to those with 11 TVs, four LVs, and six LVs.The study population included 12 individuals (3.1%) with seven cervical vertebrae (C) + 11 thoracic vertebrae (T) + five lumbar vertebrae (L), 8 (2.1%) with 7C + 11T + 6L, 8 (2.1%) with 7C + 12T + 4L, and 15 (3.9%) with 7C + 12T + 6L. Compared to the 7C + 12T + 5L individuals, those with 7C + 11T + 5L had significantly lower CAsymptomatic adults with 7C + 12T + 6L, 7C + 12T + 4L, and 7C + 11T + 5L presented with different spinal sagittal alignment compared to those with 7C + 12T + 5L. Compared to variation in the number of LVs, the variation in the number of TVs had less effect on global spinal sagittal parameters. Spinal surgeons and researchers should be aware of the effects of variation in numbers of TVs and LVs on global spinal parameters and sagittal balance.

In this work, metal-organic frameworks (MOFs) are utilized as effective ECL coreactant accelerator to enhance the ECL responses of

Bi2S3/BiOCl (denoted as BS-BC) heterojunction photocatalyst has been reported to be able to increase light absorption, promote charge separation and consequently enhance photocatalytic efficiency in comparison with single BiOCl. However, the heterojunction was usually prepared by a two-step method, i.e., BiOCl was firstly prepared and then to BS-BC heterojunction through an ion exchange strategy. In this work, BS-BC was prepared by a one-pot room temperature route, where Bi(NO3)3 dissolved in aqueous urea solution could homogeneously react with a mixture solution of NaCl and thiacetamide (TAA) to form BS-BC heterojunction. The urea could prohibit the hydrolysis of Bi(NO3)3 and accelerate the decomposition of TAA to release S2-, and as a consequence, the heterojunction photocatalyst with small size and large interfacial area could be prepared in several hours. The resulted heterojunction exhibited better visible-light photocatalytic activity for RhB degradation than individual BiOCl or that prepared by a two-step route due to close contact between Bi2S3 and BiOCl, modified band structures and effective interfacial charge transfer.

The simulation of groundwater flow is widely used to understand dynamic groundwater processes and frequently serves as the basis for quantitative analysis and management of groundwater resources. Reliable groundwater flow simulations require a sound understanding of the hydrogeological structure of the subsurface materials. However, a detailed model of the hydrological structure of thick unconsolidated basin sediments is often limited by their inaccessible nature, especially in the deep domain. As a result, deep regional flow is generally neglected in traditional groundwater flow simulations. This study presents an integrated approach for developing a model of hydrogeological structures using multiple data sources, including audio-magnetotelluric data (AMT), borehole data, and the interpreted lower boundary of Quaternary sediments. The approach overcomes the disadvantages of using the depth of boreholes as the lower boundary of the hydrogeological system and may be used to analyse the effects of hydrogeological structures on groundwater flow simulations. The model, which utilized sequential Gaussian simulation (SGS) and natural neighbor interpolation (NNI), was evaluated by application to a typical cross-section through the Yinchuan Basin, China, to a depth of 1,700 m. The horizontal hydraulic conductivity (Kx) field was calibrated using observation wells and the PEST pilot points (PPP) method. The effects of the developed hydrogeological structure on groundwater flow simulations were evaluated for the entire thickness of Quaternary sediments (complete-domain model, CDM) as well as for sediments above the maximum depth of the boreholes (shallow-domain model, SDM). In addition, the sensitivity of the Kx field on groundwater flow patterns was analysed. The results show that the proposed approach can characterize the spatial distribution of lithologic units and the heterogeneity of hydrogeological parameters in the deep domain (>300 m), as well as avoid the multi-solution problem of inferring hydrogeological parameters from geophysical data. It can also improve the accuracy of the hydrogeological structure model and the reliability of groundwater flow simulations. The adjustment of the hydrogeological structure affects the flow budget as well as the pattern of the groundwater flow systems (including the type of system, and their number, location, and extent). Changes in the Kx field affect the local flow field, whereas adjustment of the hydrogeological structure model affects the global flow field.

Clubroot, caused by the soil-borne obligate pathogen Plasmodiophora brassicae, is one of the most severe disease in cruciferous crops. Previous studies showed that when oilseed rape was planted after soybean (namely soybean-oilseed rotation), the incidence and severity of clubroot of oilseed rape could be significantly reduced, compared with that with oilseed rape-oilseed rape conti-nuous cropping. Therefore, the soybean-oilseed rape rotation is a good way to suppress clubroot of oilseed rape. In this study, we compared the rhizosphere microbiome of soybean and oilseed rape rhizosphere soil collected from the field by 16S rRNA (for identification of prokaryotes) and the internal transcribed spacer (ITS) (for identification of fungi) sequencing. The results showed that both soybean and oilseed rape rhizosphere soils had Proteobacteria, Bacteroidetes, Acidobacteria, Actinobacteria, Ascomycota, Zygomycota, Basidiomycota and Chytridiomycota. Many microbial genera (e.g., Flavobacterium, Sphingomonas, Bacillus, Streptomyces, Pseudomonas, Trichoderma and Coniothyrium) with activities of biological control and plant growth promotion were more abundant in soybean rhizosphere soil than in the oilseed rape rhizosphere soil. The abundance of plant pathogenic bacteria and fungi was higher in the oilseed rape rhizosphere soil than in the soybean rhizosphere soil. Moreover, the soybean rhizosphere soil was enriched with Rhizobium, Bradyrhizobium (both for nitrogen fixation), and arbuscular mycorrhizal fungus (Glomus). These results indicated that soybean rhizosphere soil could promote the growth and proliferation of beneficial microorga-nisms, but inhibit that of plant pathogens. Our results provide evidence for explanation of the effectiveness of soybean-oilseed rape rotation to control clubroot of oilseed rape and provide potential bio-control resources for clubroot prevention.根肿病是由芸薹根肿菌侵染引起的专性寄生性土传病害,严重制约着油菜等十字花科作物的可持续生产.前期研究发现,大豆作为前茬作物可以显著降低后茬油菜根肿病的发生和危害,“豆-油轮作”模式是一种值得探索和应用的根肿病防治新途径.为了解开大豆作为前茬防治根肿病发生的机理,本研究基于扩增子测序技术探究大豆与油菜根际土壤微生物的群落结构差异.结果表明: 大豆和油菜根际土壤微生物类群在门水平的优势类群相同,包括变形菌门、拟杆菌门、酸杆菌门、放线菌门、子囊菌门、接合菌门、担子菌门和壶菌门等丰度都较高.但相比于油菜根际土壤,大豆根际土壤富含具有生防作用和促进植物生长的微生物,如黄杆菌属、鞘脂单胞菌属、芽孢杆菌属、链霉菌属、假单胞菌属、木霉属和盾壳霉属等;而一些植物病原细菌(如肠杆菌、黄单胞菌)和真菌(炭疽菌和尾孢菌)含量则低于油菜根际土壤;另外,大豆根际土壤中还富含具有固氮功能的根瘤菌属、慢生根瘤菌属和丛枝菌根真菌(如球囊霉属).可见,大豆根际土壤利于有益微生物生长并可抑制病原菌繁殖.大豆和油菜根际微生物组差异为大豆-油菜轮作防治根肿病提供了理论依据,并为根肿病的防治提供了一些潜在的生物防治资源.

Bi2S3/BiOCl (denoted as BS-BC) heterojunction photocatalyst has been reported to be able to increase light absorption, promote charge separation and consequently enhance photocatalytic efficiency in comparison with single BiOCl. However, the heterojunction was usually prepared by a two-step method, i.e., BiOCl was firstly prepared and then to BS-BC heterojunction through an ion exchange strategy. In this work, BS-BC was prepared by a one-pot room temperature route, where Bi(NO3)3 dissolved in aqueous urea solution could homogeneously react with a mixture solution of NaCl and thiacetamide (TAA) to form BS-BC heterojunction. The urea could prohibit the hydrolysis of Bi(NO3)3 and accelerate the decomposition of TAA to release S2-, and as a consequence, the heterojunction photocatalyst with small size and large interfacial area could be prepared in several hours. The resulted heterojunction exhibited better visible-light photocatalytic activity for RhB degradation than individual BiOCl or that prepared by a two-step route due to close contact between Bi2S3 and BiOCl, modified band structures and effective interfacial charge transfer.

Distance education technology has been broadly applied in various subjects. It also leads to more revolution to teaching models, such as MOOC, flipped classroom, and live streaming teaching. To evaluate the efficacy of live streaming teaching compared to real class teaching, we investigate its application in two phrases—voice streaming and camera streaming. The study implements these two phrases facilitated by an e-community group to achieve class management. Under the guideline of positivism, this study developed a survey to examine live streaming teaching in respect of its conduct, learner acceptance, and teaching efficiency. It was found that it could assist learning in timing and location flexibility, interaction quality, and material variety, offering insights on open learning. Based on these, we conclude that there is fundamental need for further exploration with this new teaching method to advance the science of learning.

Male infertility is a multifactorial syndrome encompassing a wide variety of disorders. In recent years, several genome-wide single-nucleotide polymorphism (SNP) association studies (GWAS) have been performed on azoospermia and/or oligozoospermia in different populations including two GWAS on nonobstructive azoospermia in China; however, the association of SNPs with idiopathic male infertility, especially asthenozoospermia and oligozoospermia, and their correlation with semen parameters are still not clear. To investigate genetic variants associated with idiopathic male infertility (asthenozoospermia, oligozoospermia, and oligoasthenozoospermia) in Chinese Han people, 20 candidate SNPs were selected from GWAS results and genotyped using the Sequenom MassARRAY assay. A total of 136 subfertile men and 456 healthy fertile men were recruited. rs6476866 in SLC1A1 (P = 1.919E-4, OR = 0.5905, 95% CI: 0.447–0.78) and rs10129954 in DPF3 (P = 0.0023, OR = 2.199, 95% CI: 1.311–3.689) were strongly associated with idiopathic male infertility. In addition, positive associations were observed between asthenozoospermia and rs215702 in LSM5 (P = 0.0016, OR = 1.479, 95% CI: 1.075–2.033) and between oligoasthenozoospermia and rs2477686 in PEX10 (P = 0.0011, OR = 2.935, 95% CI: 1.492–5.775). In addition, six SNPs (rs215702 in LSM5, rs6476866 in SLC1A1, rs10129954 in DPF3, rs1801133 in MTHFR, rs2477686 in PEX10, and rs10841496 in PED3A) were significantly correlated with semen quality alterations. Our results suggest that idiopathic male infertility in different ethnic groups may share the same mechanism or pathway. Cohort expansion and further mechanistic studies on the role of genetic factors that influence spermatogenesis and sperm progressive motility are suggested.

Since digital media is gaining popularity nowadays, people are more concerned about its integrity protection and authentication since tampered media may result in unexpected problems. Considering a better media protection technique, this paper proposes an efficient tamper detection scheme for absolute moment block truncation coding (AMBTC) compressed images. In AMBTC, each image block is represented by two quantization levels (QLs) and a bitmap. Requiring insignificant computation cost, it attracts not only a wide range of application developers, but also a variety of studies to investigate the authentication of its codes. While the existing methods protect the AMBTC codes to a large extent, the leakage of some unprotected codes may be insensitive to intentional tampering. The proposed method fully protects the AMBTC codes by embedding authentication codes (ACs) into QLs. Meanwhile, the most significant bits of QLs are symmetrically perturbed to generate the candidates of ACs. The ACs that cause the minimum distortion are embedded into the least significant bits of QLs to minimize the distortion. When compared with prior works, the experimental results reveal that the proposed method offers a significant sensitivity-of-tamper property while providing a comparable image quality.

Telomeres are evolutionary conserved, multifunctional DNA-protein complexes located at the ends of eukaryotic chromosomes. Telomeres maintain chromosome stability and genome integrity and also play an important role in meiosis which aid in synapsis, homologous recombination, and segregation. Sperm telomere has been reported to play an important role in fertilization and embryo development. Nowadays, the association between telomere and reproduction is one of the major areas of interest, however whether sperm telomere associated with male infertility is not clear. In this study, in order to find out the association between Chinese idiopathic infertility and sperm telomere length, we analyzed the difference of sperm telomere length between idiopathic infertile men and normal fertile men, as well as the correlations between sperm telomere length and human semen characteristics. We analyzed 126 Chinese idiopathic infertile men and 138 normal fertile men for sperm telomere length by using quantitative PCR. We found that the relative sperm mean telomere length of infertile men was significantly shorter than that of fertile men (2.894 ± 0.115 vs. 4.016 ± 0.603, P=5.097 x 10⁻⁵). Both sperm count and semen progressive motility are related with telomere length. Our results suggest that sperm telomere length is associated with idiopathic male infertility of China and we proposed the possibility that shorter telomeres in sperm chromosome will reduce spermatogenesis and sperm functions, which finally affected the fertility of male.