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Abstract CRISPR/Cas12a is a highly promising detection tool. However, detecting single nucleotide variations (SNVs) remains challenging. Here, we elucidate Cas12a specificity through crRNA engineering and profiling of single- and double-base mismatch tolerance across three targets. Our findings indicate that Cas12a specificity depends on the number, type, location, and distance of mismatches within the R-loop. We also find that introducing a wobble base pair at position 14 of the R-loop does not affect the free energy change when the spacer length is truncated to 17 bp. Therefore, we develop a new universal specificity enhancement strategy via iterative crRNA design, involving truncated spacers and a wobble base pair at position 14 of the R-loop, which tremendously increases specificity without sacrificing sensitivity. Additionally, we construct a PAM-free one-pot detection platform for SARS-CoV-2 variants, which effectively distinguishes SNV targets across various GC contents. In summary, our work reveals new insights into the specificity mechanism of Cas12a and demonstrates significant potential for in vitro diagnostics.

Abstract Background Type 2 diabetes mellitus (T2DM) is a common metabolic disease that requires long-term management and treatment. Digital intervention, as an emerging medical model, has been widely used in the treatment of T2DM patients. Behavioral economics theory provides a favorable perspective for studying the effect of digital intervention because it can reveal the decision-making mechanisms behind human behavior and provide more effective interventions for digital intervention. The purpose of this trial is to evaluate the impact of behaviorally based digital intervention on T2DM patients’ HbA1c, self-monitoring of blood glucose (SMBG) testing rate, diabetes self-efficacy, and other indicators compared to conventional treatment. Methods This trial is a prospective randomized controlled trial conducted at the First People’s Hospital of Kunshan City from April 1, 2023, to December 31, 2024, with a follow-up period of 3 months. The specific randomization method was established and implemented through the EDC clinical trial center’s randomization system. We will measure and collect baseline data from three groups, including Group A: digital intervention + virtual incentives + conventional treatment, Group B: digital intervention + physical incentives + conventional treatment, and Group C: conventional treatment. HbA1c, weight, SMBG testing rate, diabetes self-efficacy, and diabetes-related medical expenses will be recorded at baseline, 1 month, 2 months, and 3 months for all three groups. The Shapiro-Wilk test will be used to test for normality, and Pearson correlation analysis will be used for correlation analysis. Dropouts will be analyzed separately. Analysis of variance or exact probability calculation will be used to compare demographic data and other baseline indicators. Discussion This study is a novel clinical trial that integrates multiple disciplines (economics and medicine) and uses digital technology to deliver the intervention. Most published studies were offline interventions based on behavioral economics theory, but very few were on online interventions for T2DM patients. This study has both novelty and social value. Trial registration Chinese Clinical Trial Registry ChiCTR2300070753. Registered on 2023/04/22.

Infertility affects approximately 10–15% of couples worldwide who are attempting to conceive, with male infertility accounting for 50% of infertility cases. Male infertility is related to various factors such as hormone imbalance, urogenital diseases, environmental factors, and genetic factors. Owing to its relationship with genetic factors, male infertility cannot be diagnosed through routine examination in most cases, and is clinically called ‘idiopathic male infertility.’ Recent studies have provided evidence that microRNAs (miRNAs) are expressed in a cell-or stage-specific manner during spermatogenesis. This review focuses on the role of miRNAs in male infertility and spermatogenesis. Data were collected from published studies that investigated the effects of miRNAs on spermatogenesis, sperm quality and quantity, fertilization, embryo development, and assisted reproductive technology (ART) outcomes. Based on the findings of these studies, we summarize the targets of miRNAs and the resulting functional effects that occur due to changes in miRNA expression at various stages of spermatogenesis, including undifferentiated and differentiating spermatogonia, spermatocytes, spermatids, and Sertoli cells (SCs). In addition, we discuss potential markers for diagnosing male infertility and predicting the varicocele grade, surgical outcomes, ART outcomes, and sperm retrieval rates in patients with non-obstructive azoospermia (NOA).

BackgroundCellulitis is defined as an infection of the skin that is usually characterized by localized but poorly demarcated areas of erythema, swelling, and pain. Erysipelas is a subtype of cellulitis that is characterized by a more superficial infection, often involving the face. Because gram-positive bacteria are the most common infective agent, beta-lactam antibiotics such as cephalosporins are commonly used. However, guidelines and physician preference vary widely as different antibiotic options and routes of administration exist, in addition to the fact that most cases are treated empirically without microbiological lab guidance. This lack of standardization in evidence, guidelines, and physician practice prompted this systematic review and meta-analysis of both randomized trial data and cohort studies to aggregate the currently available evidence for the optimal routes of antibiotic administration in cellulitis treatment. ObjectiveThe primary objective of our review is to compare the efficacy of oral versus intravenous antibiotic administration for cellulitis infections, thereby providing clinicians with evidence-based guidelines for treatment. MethodsWe will search MEDLINE, Embase, and CENTRAL through Ovid as well as Web of Science and CINAHL for all available literature comparing different routes of antibiotic administration in the treatment of cellulitis and erysipelas. We will perform title and abstract as well as full-text screening in duplicate according to the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines and then extract the relevant data using a prepiloted data sheet. The primary outcome for our review is the duration of infection resolution, and secondary outcomes such as incidence of sepsis, mortality, hospital admission, and Clostridium difficile infection. We will assess the risk of bias in our included studies using the RoB 2.0 (revised tool for Risk of Bias in randomized trials) and ROBINS-I (Risk of bias in non-randomized studies for interventions) tools, with a final quality assessment using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework and a sensitivity analysis to examine heterogeneity. ResultsWe will publish the final results of our systematic review in a peer-reviewed academic journal. This project received no funding or financial assistance. Data analysis is currently underway, and the results are expected to be submitted for publication in late November 2023. ConclusionsTo our knowledge, this will be the most up-to-date review of the best available evidence comparing different routes of antibiotic administration for cellulitis. Because of the vast selection of antibiotic options available and the empirical nature of the treatment, we anticipate heterogeneity within our data but nonetheless hope to provide aggregated evidence on the efficacy of intravenous versus oral administration of antibiotics in cellulitis treatment. We hope the results from this study will better inform physician practices in the future for cellulitis infections. International Registered Report Identifier (IRRID)PRR1-10.2196/48342

Objectives: The non-O1/non-O139 Vibrio cholerae caused outbreaks or sporadic cases of gastroenteritis that was rarely seen in good sanitary condition. It was described a case of systemic multiple organ lesions that worsened because of non-O1/non-O139 V. cholerae, suggesting that serogroups have a potential virulence in enhancing pathogenicity with patients with underlying diseases compared with a healthy population. Design or methods: Samples are identified by strain culture, polymerase chain reaction (PCR) virulence identification, and whole genome sequencing. Results: A middle-aged man was diagnosed with cytotoxin-producing and nontoxin V. cholerae non-O1/non-O139 serogroups. Although lacking the CT toxin encoded by ctxAB gene, the pathogenesis of cholera relies on the synergistic action of many other genes, especially virulence genes. Conclusions: This case suggested that the laborers engaging in agricultural production are at potential risk of V. cholerae infection by exposure of open wounds to contaminated water . However, epidemiological investigation should focus on the objective cause of the change of working environment. Furthermore, common diseases can possibly enhance the virulence of non-O1/non-O139 serogroups by attacking the tight junction of small intestinal epithelial cells, further triggering bacteremia, a process that may lead to death within 48–72 hours, which requires great attention.

Generating canopy-reflectance datasets using radiative transfer models under various leaf and soil optical property combinations is important for remote sensing retrieval of vegetation parameters. One-dimensional radiative transfer models have been frequently used. However, three-dimensional (3D) models usually require detailed 3D information that is difficult to obtain and long model execution time, limiting their use in remote sensing applications. This study aims to address these limitations for practical use of 3D models, proposing a semi-empirical speed-up method for canopy-reflectance simulation based on a LargE-Scale remote sensing data and image Simulation model (LESS), called Semi-LESS. The speed-up method is coupled with 3D LESS to describe the dependency of canopy reflectance on the wavelength, leaf, soil, and branch optical properties for a scene with fixed 3D structures and observation/illumination configurations, allowing fast generating accurate reflectance images under various wavelength-dependent optical parameters. The precomputed dataset stores simulated multispectral coefficient images under few predefined soil, branch, and leaf optical properties for each RAdiation transfer Model Intercomparison-V scene, which can then be used alone to compute reflectance images on the fly without the participation of LESS. Semi-LESS has been validated with full 3D radiative-transfer-simulated images, showing very high accuracy (root mean square error < 0.0003). The generation of images using Semi-LESS is much more efficient than full LESS simulations with an acceleration of more than 320 times. This study is a step further to promote 3D radiative transfer models in practical remote sensing applications such as vegetation parameter inversions.

Litter decomposition is an important source of carbon accumulation in the permafrost peatlands. Climate warming has led to shrub expansions and accelerated litter mixing with soils and fluctuations in the water table. However, little is known about how changes in the position of the litter will affect litter decomposition under climate warming. To reveal the mechanisms of response of the location of litter in the soil and climate warming to litter decomposition in permafrost peatlands. Here, we selected the evergreen shrub, Chamaedaphne calyculata, and the deciduous shrub, Vaccinium uliginosum, from the permafrost peatlands of the Greater Hing’an Mountains, China. The leaf litter was placed on the soil surface (no-mixing) and mixed with the soil (soil-litter mixing), and then it was incubated for 124 days at 15°C (control) and 20°C (warming). Our results showed that warming significantly increased the CO2 emission rates of C. calyculata and V. uliginosum by 19.9 and 17.4%, respectively. When compared to no-mixing, the CO2 emission rates were reduced (not significantly) by 1.5 (C. calyculata) and increased 13.6% (V. uliginosum) with soil-litter mixing. Interestingly, soil-litter mixing suppressed the positive effect of warming on the CO2 emission rates relative to no-mixing, and the suppressing effects in the V. uliginosum subplot were stronger than those in the C. calyculata subplot. Specifically, warming significantly increased the CO2 emissions of C. calyculata by 27.4% under no-mixing but the increase decreased to 13.1% under soil-litter mixing. Similarly, warming induced significant increases in the CO2 emissions of V. uliginosum, with an increase of 38.8% under no-mixing but non-significant increases (1.9%) were observed under soil-litter mixing. The combination of the enzyme activities of β-1,4-glucosidase, β-1,4-xylosidase and β-D-1,4-cellobiosidase and laccase and phenolics explained more than 60.0% of the variability in the CO2 emissions of C. calyculata and V. uliginosum, respectively. Our study highlights the importance of litter positions in mediating the responses of litter decomposition to climate warming and shrub expansions in the northern peatlands.

The alterations of plant composition and diversity pose a threat to the stability of the carbon pool in boreal peatland under climate change. We collected the samples of three plant functional types (deciduous shrubs, evergreen shrubs, and sedge) in seven permafrost peatlands of the Great Hing’an Mountains, China, and measured the properties of total carbon (TC), nitrogen (TN), and phosphorus (TP), their stoichiometric ratios (C:N, C:P, and N:P), and the stable isotope values (δ13C and δ15N) of six tissues (ranging from leaves to roots). For TC, TN, and TP, the contents had an average of 470.69 ± 1.56, 8.03 ± 0.23, and 1.71 ± 0.61 mg·g−1, respectively. TC contents of sedge were lower than those of shrubs for the whole plant. The allocations of N and P to shrub leaves were higher than to stems and roots. There was a similar trend of TN and TP contents, and stoichiometric ratios from leaves to roots between deciduous shrubs and evergreen shrubs. Shrubs and sedge have similar C: N in leaves and fine roots, while leaves of sedge C:P and N:P ratios were higher than shrubs, mainly showed that sedge is N and P co-limitation and shrubs are N limitation. The values of δ13C and δ15N were significantly higher in leaves and roots of sedge than those of shrubs, which means shrubs have higher nutrient acquisition strategies. These results support the shrubs are expanding in the boreal peatland under climate warming through nutrient competition. TC contents of all deciduous shrubs and sedge tissues were positively linear correlated to MAT and the values of δ13C and δ15N in sedge had significant relationships with MAT and MAP. Our results imply warming can increase plant photosynthesis in boreal peatland, and sedge was more sensitive to climate change. These findings would be helpful to understanding the responses of different plant tissues to climate changes in permafrost peatland.

Root rot disease caused by Fusarium oxysporum is a devastating disease of Salvia miltiorrhiza and dramatically affected the production and quality of Sa. miltiorrhiza. Besides the agricultural and chemical control, biocontrol agents can be utilized as an additional solution. In the present study, an actinomycete that highly inhibited F. oxysporum was isolated from rhizosphere soil and identified as based on morphological and molecular characteristics. Greenhouse assay proved that the strain had significant biological control effect against Sa. miltiorrhiza root rot disease and growth-promoting properties on Sa. miltiorrhiza seedlings. To elucidate the biocontrol and plant growth-promoting properties of St-220, we employed an analysis combining genome mining and metabolites detection. Our analyses based on genome sequence and bioassays revealed that the inhibitory activity of St-220 against F. oxysporum was associated with the production of enzymes targeting fungal cell wall and metabolites with antifungal activities. Strain St-220 possesses phosphate solubilization activity, nitrogen fixation activity, siderophore and indole-3-acetic acid production activity in vitro, which may promote the growth of Sa. miltiorrhiza seedlings. These results suggest that St. albidoflavus St-220 is a promising biocontrol agent and also a biofertilizer that could be used in the production of Sa. miltiorrhiza.

Abstract The allogeneic transplantation of primordial germ cells (PGCs) derived from somatic cells overcomes the limitation of avian cloning. Here, we transdifferentiate chicken embryo fibroblasts (CEFs) from black feathered Langshan chickens to PGCs and transplant them into White Plymouth Rock chicken embryos to produce viable offspring with characteristics inherited from the donor. We express Oct4/Sox2/Nanog/Lin28A (OSNL) to reprogram CEFs to induced pluripotent stem cells (iPSCs), which are further induced to differentiate into PGCs by BMP4/BMP8b/EGF. DNA demethylation, histone acetylation and glycolytic activation elevate the iPSC induction efficiency, while histone acetylation and glycolytic inhibition facilitate PGCs formation. The induced PGCs (iPGCs) are transplanted into the recipients, which are self-crossed to produce 189/509 somatic cells derived chicken with the donor’s characteristics. Microsatellite analysis and genome sequencing confirm the inheritance of genetic information from the donor. Thus, we demonstrate the feasibility of avian cloning from somatic cells.

Leaf area index (LAI) and canopy chlorophyll content (CCC) are important indicators that describe the growth status and nitrogen deficiencies of crops. Several studies have been performed to estimate LAI and CCC using multispectral cameras onboard an unmanned airborne vehicle (UAV) system. However, the impacts of illuminations during UAV flight and problems of how to invert still need more investigation. UAV flights with a multispectral camera were performed under clear (diffuse ratio 0) and cloudy illumination conditions (diffuse ratio 1) over rapeseed, wheat and sunflower (only clear) fields. One-dimension radiative transfer model PROSAIL was run twice to generate a clear-sky model and a cloudy-sky model, respectively. The LAI and CCC of flights under a clear sky were inverted from the clear-sky model, and the flights under cloudy conditions were inverted from both clear-sky and cloudy-sky models to compare the results. Moreover, three Look-Up-Tables (LUT) were built with same input variables but different distributions of LAI. Results showed that LAI from uniform dense LUT had better correspondence with ground measurements for all crops (R2 = 0.51~0.69). The illumination condition had little impact on small to medium LAI (LAI < 5) and CCC. However, the inversion of imageries during cloudy sky conditions from the clear-sky model led to an overestimation of high LAI values.

BackgroundSex differentiation is a complex and precisely regulated process by multiple genes in chicken. However, it is still unclear on the key genes of sex differentiation.ObjectiveTo explore the function of Tle4z1 screened by RNA-seq sequencing on sex differentiation during the development of chicken embryos.MethodsTle4z1 was differentially expressed from the RNA-seq of ESCs and PGCs in male and female chickens. Then, we established an effective method to overexpression or knocking down the expression of Tle4z1 in ovo and in vitro, respectively. Histomorphological observation, qRT-PCR and ELISA were applied to detect the function of Tle4z1 in the process of male sex differentiation by injecting vectors into embryos at day 0.ResultsIt showed that Tle4z1 has significant male preference in embryonic day 4.5, such phenomenon persisted during the growth period of chicken embryos. Morphological observation results showed that the gonads on both sides of genetic male (ZZ) embryos with Tle4z1 knocking down developed asymmetrically, the gonadal cortex became thicker showing the typical characteristics of genetic female (ZW) gonads. Furthermore, the expression of Cyp19a1, which dominates female differentiation, was significantly increased, while the expression of male marker genes Dmrt1, Sox9, WT1 and AR was significantly downregulated. In addition, the concentration of testosterone also significantly decreased, which was positively correlated with the expression of Tle4z1 (P < 0.01). Conversely, the ZW embryo showed defeminized development when Tle4z1 was overexpressed.ConclusionWe prove that the Tle4z1 is a novel gene through the male sexual differentiation via gene regulation process and synthesis of testosterone, which construct the basis for understanding the molecular mechanism of sex differentiation in chickens.

Accurate wall-to-wall estimation of forest crown cover is critical for a wide range of ecological studies. Notwithstanding the increasing use of UAVs in forest canopy mapping, the ultrahigh-resolution UAV imagery requires an appropriate procedure to separate the contribution of understorey from overstorey vegetation, which is complicated by the spectral similarity between the two forest components and the illumination environment. In this study, we investigated the integration of deep learning and the combined data of imagery and photogrammetric point clouds for boreal forest canopy mapping. The procedure enables the automatic creation of training sets of tree crown (overstorey) and background (understorey) data via the combination of UAV images and their associated photogrammetric point clouds and expands the applicability of deep learning models with self-supervision.Based on the UAV images with different overlap levels of 12 conifer forest plots that are categorized into “I”, “II” and “III” complexity levels according to illumination environment, we compared the self-supervised deep learning-predicted canopy maps from original images with manual delineation data and found an average intersection of union (IoU) larger than 0.9 for “complexity I” and “complexity II” plots and larger than 0.75 for “complexity III” plots. The proposed method was then compared with three classical image segmentation methods (i.e., maximum likelihood, Kmeans, and Otsu) in the plot-level crown cover estimation, showing outperformance in overstorey canopy extraction against other methods. The proposed method was also validated against wall-to-wall and pointwise crown cover estimates using UAV LiDAR and in situ digital cover photography (DCP) benchmarking methods. The results showed that the model-predicted crown cover was in line with the UAV LiDAR method (RMSE of 0.06) and deviate from the DCP method (RMSE of 0.18). We subsequently compared the new method and the commonly used UAV structure-from-motion (SfM) method at varying forward and lateral overlaps over all plots and a rugged terrain region, yielding results showing that the method-predicted crown cover was relatively insensitive to varying overlap (largest bias of less than 0.15), whereas the UAV SfM-estimated crown cover was seriously affected by overlap and decreased with decreasing overlap. In addition, canopy mapping over rugged terrain verified the merits of the new method, with no need for a detailed digital terrain model (DTM). The new method is recommended to be used in various image overlaps, illuminations, and terrains due to its robustness and high accuracy. This study offers opportunities to promote forest ecological applications (e.g., leaf area index estimation) and sustainable management (e.g., deforestation).

Grasshoppers can swarm in the millions and destroy crops over wide areas, posing a major economic threat to agriculture. A wide range of insect-related viruses has recently been reported in the metagenomics of grasshoppers. Here, we identified and isolated a novel reovirus from grasshoppers, named Acrididae reovirus (ARV). The complete genome of ARV was composed of nine dsRNA segments. Phylogenetic analysis revealed that ARV formed a monophyletic lineage with unclassified insect-associated reoviruses and was sufficiently distinct from known genera of Reoviridae. ARV could replicate in its host Locusta migratoria and result in host death. Lower-dose ARV infection affected ovary development and resulted in a significant reduction in fecundity. The identification and characterization of a novel pathogenic reovirus could potentially promote the development of new biological control agents.

We presented a theoretical study for the structural, mechanical, and thermophysical properties of the precipitates in 2xxx series aluminum alloy by applying the widely used density functional theory of Perdew-Burke-Ernzerhof (PBE). The results indicated that the most thermodynamically stable structure refers to the Al3Zr phase in regardless of its different polymorphs, while the formation enthalpy of Al5Cu2Mg8Si6 is only -0.02 eV (close to zero) indicating its metastable nature. The universal anisotropy index of AU follows the trend of: Al2Cu > Al2CuMg ≈ Al3Zr_D022 ≈ Al20Cu2Mn3 > Al3Fe ≈ Al6Mn > Al3Zr_D023 ≈ Al3Zr_L12 > Al7Cu2Fe > Al3Fe2Si. The thermal expansion coefficients (TECs) were calculated based on Quasi harmonic approximation (QHA); Al2CuMg shows the highest linear thermal expansion coefficient (LTEC), followed by Al3Fe, Al2Cu, Al3Zr_L12 and others, while Al3Zr_D022 is the lowest one. The calculated data of three Al3Zr polymorphs follow the order of L12 > D023 > D022, all of them show much lower LTEC than Al substance. For multi-phase aluminum alloys, when the expansion coefficient of the precipitates is quite different from the matrix, it may cause a relatively large internal stress, or even produce cracks under actual service conditions. Therefore, it is necessary to discuss the heat misfit degree during the material design. The discrepancy between a-Al and Al2CuMg is the smallest, which may decrease the heat misfit degree between them and improve the thermal shock resistant behaviors.

Digital aerial photogrammetry (DAP) has emerged as an alternative to airborne laser scanning (ALS) for forest inventory applications, as it offers a low-cost and flexible three-dimensional (3D) point cloud. Unlike the forest inventory attributes (e.g., tree height and diameter at breast height), the relative ability of DAP and ALS in predicting canopy structural variables (i.e., canopy cover and leaf area index (LAI)) has not been sufficiently investigated by previous studies. In this study, we comprehensively compared the canopy cover and LAI estimates using DAP- and ALS-based methods over 166 selected tropical forest sample plots with seven different tree species and forest types. We also explored the relationship between field-measured aboveground biomass (AGB) and the LAI estimates. The airborne LAI estimates were subsequently compared with the Sentinel-2-based LAI values that were retrieved using a one-dimensional radiative transfer model. The results demonstrated that the DAP-based method generally overestimated the two canopy variables compared to ALS-based methods but with relatively high correlations regardless of forest type and species (R2 of 0.80 for canopy cover and R2 of 0.76 for LAI). Under different forest types and species, the R2 of canopy cover and LAI range from 0.64 to 0.89 and from 0.54 to 0.87, respectively. Apparently, different correlations between AGB and LAI were found for different forest types and species where the mixed coniferous and broad-leaved forest shows the best correlation with R2 larger than 0.70 for both methods. The comparison with satellite retrievals verified that the ALS-based estimates are more consistent with Sentinel-2-based estimates than DAP-based estimates. We concluded that DAP data failed to provide analogous results to ALS data for canopy variable estimation in tropical forests.

Although genome sequencing has become increasingly popular, the simulation of individual genomes is still important. This is because sequencing a large number of individual genomes is costly and genome data with extreme and boundary conditions, such as fatal genetic defects, are difficult to obtain. Privacy and legal barriers also prevent many applications of real data. Large sequencing projects in recent years have provided a deeper understanding of the human genome. However, there is a lack of tools to leverage known data to simulate personal genomes as real as possible. Here, we designed and developed PGsim, a comprehensive and highly customizable individual genome simulator, that fully uses existing knowledge, such as variant allele frequencies in global or world main populations, mutation probability differences between protein-coding regions and non-coding regions, transition/transversion (Ti/Tv) ratios, Indel incidence, Indel length distribution, structural variation sites, and pathogenic mutation sites. Users can flexibly control the proportion and quantity of known variants, common variants, novel variants in both coding and non-coding regions, and special variants through detailed parameter settings. To ensure that the simulated personal genome has sufficient randomness, PGsim makes the generated variants more real and reliable in terms of variant distribution, proportion, and population characteristics. PGsim is able to employ a huge volume database as background data to simulate personal genomes and does not require SQL database support. Users can easily change the variant databases used as needed. As a Perl script, there is no obstacle to running PGsim on any version of the MAC OS or Linux systems, and no libraries, packages, interpreters, compilers, or other dependencies need to be installed in advance. The PGsim tool is publicly available at https://github.com/lrjuan/PGsim.

Abstract Background Cordyceps sinensis (C. sinensis) is a famous and precious Traditional Chinese Medicine (TCM), while frequent reports of heavy metals, especially arsenic, exceeding standards in C. sinensis in recent years have raised concerns of its safety. Therefore, it is urgent for a research on heavy metals (Cu, Pb, As, Cd, Hg) in C. sinensis, of its bioaccessibility, dietary exposure estimation, arsenic speciation analysis and health risks assessment to human body. Methods Three 30 g batches of mixed wild growth C. sinensis samples were collected from Qinghai Province and each batch were divided into three parts: the whole C. sinensis, the stroma and the caterpillar body. The in vitro gastrointestinal method was used to evaluate the bioaccessibility of the heavy metals in the samples. The arsenic speciation analysis in the in vitro gastrointestinal solutions and dilute nitric acid extracted solutions were conducted using high performance liquid chromatography–inductively coupled plasma mass (HPLC–ICP-MS) method. Finally, the target hazard quotient (THQ) developed by the US EPA (1989) was used to assess the health risks of heavy metals in C. sinensis. Results The contents of Cu, Pb, Cd and Hg in the stroma were higher than those in the caterpillar body. In contrast, As was mainly found in the caterpillar body. In the whole C. sinensis, the average bio-accessibilities of Cu, Pb, As, Hg and Cd were 41.29, 40.11, 64.46, 18.91, and 81.14%, respectively. While in the caterpillar body, the corresponding bio-accessibilities values were 48.26, 42.92, 66.15, 12.86, 87.07%, respectively, and were 38.30, 30.53, 30.18, 7.46, and 82.30%, respectively in the stroma part. Different arsenic speciations of arsenite [As(III)], arsenate [As(V)] and trace amounts of methylarsonic acid [MMA] were detected. Of the total As, 8.69% was in inorganic form, which was also the major form of dissolved As. Among the extracted inorganic species, the concentrations of As(III) and As(V) were 0.56 ± 0.16 and 0.29 ± 0.06 mg kg−1, respectively. In the gastrointestinal solutions, only As(III) and As(V) could be detected; the sum content of the two species was 2.00–2.73%. The bioaccessibility target hazard quotient (BTHQ) values for Cu, Pb, As, Cd and Hg in C. sinensis were 0.0041, 0.0040, 0.5334, 0.0020 and 0.0005, respectively, all less than 1. Conclusion None of the five heavy metals in C. sinensis can be 100% absorbed by human body. The content of arsenic in C. sinensis is high, but the strong toxic inorganic arsenic accounted for only 8.69%. The heavy metals in C. sinensis presented no obvious risks to human health in a reasonable taking way.

Abstract Background Leaf biochemical composition corresponds to traits related to the plant state and its functioning. This study puts the emphasis on the main leaf absorbers: chlorophyll a and b ($$C_{ab}$$ Cab ), carotenoids ($$C_{c}$$ Cc ), water ($$C_{w}$$ Cw ) and dry mater ($$C_{m}$$ Cm ) contents. Two main approaches were used to estimate [$$C_{ab} ,$$ Cab, $$C_{c}$$ Cc , $$C_{w}$$ Cw , $$C_{m}$$ Cm ] in a non-destructive way using spectral measurements. The first one consists in building empirical relationships from experimental datasets using either the raw reflectances or their combination into vegetation indices (VI). The second one relies on the inversion of physically based models of leaf optical properties. Although the first approach is commonly used, the calibration of the empirical relationships is generally conducted over a limited dataset. Consequently, poor predictions may be observed when applying them on cases that are not represented in the training dataset, i.e. when dealing with different species, genotypes or under contrasted environmental conditions. The retrieval performances of the selected VIs were thus compared to the ones of four PROSPECT model versions based on reflectance data acquired at two phenological stages, over six wheat genotypes grown under three different nitrogen fertilizations and two sowing density modalities. Leaf reflectance was measured in the lab with a spectrophotometer equipped with an integrating sphere, the leaf being placed in front of a white Teflon background to increase the sensitivity to leaf biochemical composition. Destructive measurements of [$$C_{ab} ,$$ Cab, $$C_{c}$$ Cc , $$C_{w}$$ Cw , $$C_{m}$$ Cm ] were performed concurrently. Results The destructive measurements demonstrated that the carotenoid, $$C_{c}$$ Cc , and chlorophyll, $$C_{ab}$$ Cab , contents were strongly correlated (r2 = 0.91). The sum of $$C_{ab}$$ Cab and $$C_{c}$$ Cc , i.e. the total chlorophyllian pigment content, $$C_{abc}$$ Cabc , was therefore used in this study. When inverting the PROSPECT model, accounting for the brown pigment content, $$C_{bp}$$ Cbp , was necessary when leaves started to senesce. The values of $$C_{abc}$$ Cabc and $$C_{w}$$ Cw were well estimated (r2 = 0.81 and r2 = 0.88 respectively) while the dry matter content, $$C_{m}$$ Cm , was poorly estimated (r2 = 0.00). Retrieval of $$C_{w}$$ Cw from PROSPECT versions was only slightly biased, while substantial overestimation of $$C_{abc }$$ Cabc was observed. The ranking between estimated values of $$C_{abc}$$ Cabc and $$C_{w}$$ Cw from the several PROSPECT versions and that derived using the VIs were similar to the ranking observed over the destructively measured values of $$C_{abc}$$ Cabc and $$C_{w}$$ Cw . Conclusions PROSPECT model inversion and empirical VI approach provide similar retrieval performances and are useful methods to estimate leaf biochemical composition from spectral measurements. However, the PROSPECT model inversion gives potential access to additional traits on surface reflectivity and leaf internal structure. This study suggests that non-destructive estimation of leaf chlorophyll and water contents is a relevant method to provide leaf traits with relatively high throughput.

To avoid the widespread resistance of commercial fungicides, new broad-spectrum botanical fungicides need to be developed. In previous bioactive screening assays, extracts of Artemisia ordosica Krasch. (A. ordosica) had highly antifungal activities, but the responsible phytochemicals were unidentified. In this study, active compounds of A. ordosica extracts were identified using a bioassay-guided method, and antifungal assays were performed in vitro and in vivo. The bioactive compounds were dissolved in petroleum ether, and the best antifungal fraction contained four compounds: trans-dehydromatricaria ester (TDDE), 7, 4-demetylnringenin, capillarin, and stearic acid. Among them, TDDE exhibited the highest antifungal activity against six pathogenic fungi and five bacteria. It exhibited significant fungicidal activity against Thanatephorus cucumeris and Botrytis cinerea with EC50 values of 0.464 μg/mL and 1.4 μg/mL, respectively. The living tissue bioassay results showed that the relative protection effects (RPE) of TDDE on tomato leaves, tomato fruit, and strawberry leaves infected with B. cinerea reached 76.78%, 86.2%, and 80.89%, respectively. In pot experiments, the RPE on tomato and strawberry plants infected with B. cinerea reached 84.11% and 96.37%, respectively. Morphological and physiological examination showed that TDDE had significant inhibitory effects on mycelial growth, including increased top offshoot, contorted hyphal tips, and extravasated cytochylema. Meanwhile, bactericidal activities of TDDE were significantly higher than kanamycin and streptomycin in five bacteria, and the plant tissue experiments further demonstrated that it had an 88.31% RPE on walnut leaves infected with Xanthomonas campestris pv. jugiandis, 72.18% RPE on potato infected with Erwinia carotovora subsp. carotovora, and 82.50% RPE on kiwifruit branches infected with Pseudomonas syringae pv. actinidiae. The active compounds isolated from A. ordosica in this study show great potential value for developing broad-spectrum fungicides, and also provide an important way to identify and isolate new bioactive products from medicinal plants.

Abstract Pepsinogen C (PGC) belongs to the aspartic protease family and is secreted by gastric chief cells. PGC could be activated to pepsin C and digests polypeptides and amino acids, but as a zymogen PGC’s functions is unclear. In normal physiological conditions, PGC is initially detected in the late embryonic stage and is mainly expressed in gastric mucosa. The in situ expression of PGC in gastric mucosa is decreased considerably in the process of superficial gastritis → atrophic gastritis → gastric cancer (GC), proving that PGC is a comparatively ideal negative marker of GC. Serum PGC, and PGA levels and the PGA/PGC ratio have satisfactory sensitivity, specificity and price–quality ratio for predicting high GC risk. Ectopic PGC expression is significantly increased in prostate cancer, breast cancer, ovary cancer and endometrial cancer. In those sex-related cancers high level PGC expression indicates better prognosis and longer survival. The regulation of PGC expression involves genetic and epigenetic alteration of the encoding PGC gene, hormones modulation and interactions between PGC with other transcription factors and protein kinases. More and more research evidence hinted that PGC has strong correlation with cancer. In the systematic review, we respectively elaborate the structure, potential physiological functions, expression characteristics and regulation of PGC, and especially focus on the relationship between PGC expression and cancer to highlight the role of PGC in the tumorigenesis and its application value in clinical practice.

The nationwide lockdown due to the COVID-19 pandemic in 2020 reduced industrial and human activities in China. In this study, we investigate atmospheric carbon monoxide (CO) concentration changes during the lockdown from observations at the surface and from two satellites (TROPOspheric Monitoring Instrument (TROPOMI) and Infrared Atmospheric Sounding Interferometer (IASI)). It is found that the average CO surface concentration in 2020 was close to that in 2019 before the lockdown, and became 18.7% lower as compared to 2019 during the lockdown. The spatial variation of the change in the CO surface concentration is high, with an 8–27% reduction observed for Beijing, Shanghai, Chengdu, Zhengzhou, and Guangzhou, and almost no change in Wuhan. The TROPOMI and IASI satellite observations show that the CO columns decreased by 2–13% during the lockdown in most regions in China. However in South China, there was an 8.8% increase in the CO columns observed by TROPOMI and a 36.7% increase observed by IASI, which is contrary to the 23% decrease in the surface CO concentration. The enhancement of the CO column in South China is strongly affected by the fire emissions transported from Southeast Asia. This study provides an insight into the impact of COVID-19 on CO concentrations both at the surface and in the columns in China, and it can be extended to evaluate other areas using the same approach.

Somatic cells can be reprogrammed into induced pluripotent stem cells (iPSCs) in vitro. Previously, a lentivirus induction strategy of introducing Oct4, Sox2, Nanog and Lin28 (OSNL) into the iPSC process has been shown as a possible way to produce chicken iPSCs from chicken embryonic fibroblasts, but the induction efficiency of this method was found to be significantly limiting. In order to help resolve this efficiency obstacle, this study seeks to clarify the associated regulation mechanisms and optimizes the reprogramming strategy of chicken iPSCs. This study showed that glycolysis and the expression of glycolysis-related genes correlate with a more efficient reprogramming process. At the same time, the transcription factors Oct4, Sox2 and Nanog were found to activate the expression of glycolysis-related genes. In addition, we introduced two small-molecule inhibitors (2i-SP) as a “glycolysis activator” together with the OSNL cocktail, and found that this significantly improved the induction efficiency of the iPSC process. As such, the study identifies direct molecular connections between core pluripotency factors and glycolysis during the chicken iPSC induction process and, with its results, provides a theoretical basis and technical support for chicken somatic reprogramming.

Small-scale placer mining in Colombia takes place in rural areas and involves excavations resulting in large footprints of bare soil and water ponds. Such excavated areas comprise a mosaic of challenging terrains for cloud and cloud-shadow detection of Sentinel-2 (S2A and S2B) data used to identify, map, and monitor these highly dynamic activities. This paper uses an efficient two-step machine-learning approach using freely available tools to detect clouds and shadows in the context of mapping small-scale mining areas, one which places an emphasis on the reduction of misclassification of mining sites as clouds or shadows. The first step is comprised of a supervised support-vector-machine classification identifying clouds, cloud shadows, and clear pixels. The second step is a geometry-based improvement of cloud-shadow detection where solar-cloud-shadow-sensor geometry is used to exclude commission errors in cloud shadows. The geometry-based approach makes use of sun angles and sensor view angles available in Sentinel-2 metadata to identify potential directions of cloud shadow for each cloud projection. The approach does not require supplementary data on cloud-top or bottom heights nor cloud-top ruggedness. It assumes that the location of dense clouds is mainly impacted by meteorological conditions and that cloud-top and cloud-base heights vary in a predefined manner. The methodology has been tested over an intensively excavated and well-studied pilot site and shows 50% more detection of clouds and shadows than Sen2Cor. Furthermore, it has reached a Specificity of 1 in the correct detection of mining sites and water ponds, proving itself to be a reliable approach for further related studies on the mapping of small-scale mining in the area. Although the methodology was tailored to the context of small-scale mining in the region of Antioquia, it is a scalable approach and can be adapted to other areas and conditions.

Although lncRNAs have been identified as playing critical roles in the development of germ cells, their potential involvement in the development of PGCs in chickens remains poorly understood. Differentially expressed lncRNAs (DELs) from previous RNA-seq of embryonic stem cells (ESCs), PGCs, and spermatogonial stem cells (SSCs) were analyzed by K-means clustering, from which a key candidate, lncRNA (lncRNA PGC regulator, LncPGCR) was obtained. We confirmed that LncPGCR plays a positive role in the development of PGCs by increasing the expression of the PGC marker gene (Cvh and C-kit), while downregulating the pluripotency-associated gene (Nanog) in vitro and in vivo. The activation and expression of LncPGCR are regulated by histone acetylation, and transcription factor TCF7L2. Mechanistically, a rescue assay was performed to further confirm that LncPGCR contributed to the development of PGCs by regulating the gga-miR-6577-5p/Btrc signaling pathway. Adsorption of gga-miR-6577-5p activated the WNT signaling cascade by relieving the gga-miR-6577-5p-dependent inhibition of Btrc expression. Taken together, our study discovered the growth-expedited role of LncPGCR in PGCs development, showing the potential LncPGCR/miR-6577-5p/Btrc pathway. The results and findings provide a novel insight into the development of PGCs.

High-quality leaf area index (LAI) products retrieved from satellite observations are urgently needed for crop growth monitoring and yield estimation, land-surface process simulation and global change studies. In recent years, sequential assimilation methods have been increasingly used to retrieve LAI from time series remote-sensing data. However, the inherent characteristics of these sequential assimilation methods result in temporal discontinuities in the retrieved LAI profiles. In this study, a sequential assimilation method with incremental analysis update (IAU) was developed to jointly update model states and parameters and to retrieve temporally continuous LAI profiles from time series Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data. Based on the existing multi-year Global Land Surface Satellite (GLASS) LAI product, a dynamic model was constructed to evolve LAI anomalies over time. The sequential assimilation method with an IAU technique takes advantage of the Kalman filter (KF) technique to update model parameters, uses the ensemble Kalman filter (EnKF) technique to update LAI anomalies recursively from time series MODIS reflectance data and then calculates the temporally continuous LAI values by combining the LAI climatology data. The method was tested over eight Committee on Earth Observing Satellites-Benchmark Land Multisite Analysis and Intercomparison of Products (CEOS-BELMANIP) sites with different vegetation types. The results indicate that the sequential method with IAU can precisely reconstruct the seasonal variation patterns of LAI and that the LAI profiles derived from the sequential method with IAU are smooth and continuous.

Currently, multiple leaf area index (LAI) products retrieved from remote sensing data are widely used in crop growth monitoring, land-surface process simulation and studies of climate change. However, most LAI products are only retrieved from individual satellite observations, which may result in spatial-temporal discontinuities and low accuracy in these products. In this paper, a new method was developed to simultaneously retrieve multiscale LAI data from satellite observations with different spatial resolutions based on an ensemble multiscale filter (EnMsF). The LAI average values corresponding to the date of satellite observations were calculated from the multi-year Moderate Resolution Imaging Spectroradiometer (MODIS) LAI product and were used as a priori knowledge for LAI in order to construct an initial ensemble multiscale tree (EnMsT). Satellite observations obtained at different spatial resolutions were then applied to update the LAI values at each node of the EnMsT using a two-sweep filtering procedure. Next, the retrieved LAI values at the finest scale were used as a priori knowledge for LAI for the new round of construction and updating of the EnMsT, until the sum of the difference of LAI values at each node of the EnMsT between two adjacent updates is less than a given threshold. The method was tested using Thematic Mapper (TM) or Enhanced Thematic Mapper Plus (ETM+) surface reflectance data and MODIS surface reflectance data from five sites that have different vegetation types. The results demonstrate that the retrieved LAI values for each spatial resolution were in good agreement with the aggregated LAI reference map values for the corresponding spatial resolution. The retrieved LAI values at the coarsest scale provided better accuracy with the aggregated LAI reference map values (root mean square error (RMSE) = 0.45) compared with that obtained from the MODIS LAI values (RMSE = 1.30).

BACKGROUND: Studying the dispersal range of Anopheles sinensis is of major importance for understanding the transition from malaria control to elimination. However, no data are available regarding the dispersal range of An. sinensis in China. The aim of the present study was to study the dispersal range of An. sinensis and provide the scientific basis for the development of effective control measures for malaria elimination in China. METHODOLOGY/PRINCIPAL FINDINGS: Mark-Release-Recapture (MRR) experiments were conducted with 3000 adult wild An. sinensis in 2010 and 3000 newly emerged wild An. sinensis in 2011 in two villages of Yongcheng City in Henan Province. Marked An. sinensis were recaptured daily for ten successive days using light traps. The overall recapture rates were 0.83% (95% CI, 0.50%~1.16%) in 2010 and 1.33% (95% CI, 0.92%~1.74%) in 2011. There was no significant difference in the recapture rates of wild An. sinensis and newly emerged An. sinensis. The majority of An. sinensis were captured due east at study site I compared with most in the west at study site II. Eighty percent and 90% of the marked An. sinensis were recaptured within a radius of 100 m from the release point in study site I and II, respectively, with a maximum dispersal range of 400 m within the period of this study. CONCLUSIONS/SIGNIFICANCE: Our results indicate that local An. sinensis may have limited dispersal ranges. Therefore, control efforts should target breeding and resting sites in proximity of the villages.

The occurrence of Giardia and Cryptosporidium (oo)cysts in drinking source water poses a serious public health risk. Here, we established a method that combines membrane concentration and real-time polymerase chain reaction (PCR) to quantify Giardia and Cryptosporidium in drinking water. The water samples were filtered through a cellulose membrane to collect Giardia and Cryptosporidium, and then nucleic acids were extracted. Specific primers and probes were designed and synthesized according to the gph gene sequence of Giardia and 18S rRNA gene sequence of Cryptosporidium. The concentrations of the two targets were determined using real-time PCR technology. The sensitivity, specificity, and stability of the method were evaluated. Our findings revealed that the detection limits of real-time PCR method for detecting Giardia and Cryptosporidium were 0.926 and 0.65 copy/µL, respectively; the spiked recovery rates were above 60% and 38%, respectively, and relative standard deviations were under 0.95% and 2.26%, respectively. Therefore, this effective procedure based on the membrane concentration method and real-time PCR will be useful for detecting Giardia and Cryptosporidium in drinking water for purpose of continuous environmental monitoring. [ABSTRACT FROM AUTHOR]

Discusses activities for developing students' listening comprehension in English-as-a-foreign-language classrooms in China. The activities have proved successful, and students participating in these courses have done well on the National Test for English Majors Band 4. (Author/VWL)

During chlorine disinfection of drinking water, chlorine may react with natural organic matter (NOM) and bromide ion in raw water to generate halogenated disinfection byproducts (DBPs). To mitigate adverse effects from DBP exposure, granular activated carbon (GAC) adsorption has been considered as one of the best available technologies for removing NOM (DBP precursor) in drinking water treatment. Recently, we have found that many aromatic halogenated DBPs form in chlorination, and they act as intermediate DBPs to decompose and form commonly known DBPs including trihalomethanes and haloacetic acids. In this work, we proposed a new approach to controlling drinking water halogenated DBPs by GAC adsorption of intermediate aromatic halogenated DBPs during chlorination, rather than by GAC adsorption of NOM prior to chlorination (i.e., traditional approach). Rapid small-scale column tests were used to simulate GAC adsorption in the new and traditional approaches. Significant reductions of aromatic halogenated DBPs were observed in the effluents with the new approach; the removals of total organic halogen, trihalomethanes, and haloacetic acids by the new approach always exceeded those by the traditional approach; and the effluents with the new approach were considerably less developmentally toxic than those with the traditional approach. Our findings indicate that the new approach is substantially more effective in controlling halogenated DBPs than the traditional approach. [ABSTRACT FROM AUTHOR]

Climate change is affecting every aspect of human activities, especially the agriculture. In China, extreme drought events caused by climate change have posed a great threat to food safety. In this work we aimed to study the drought risk of maize in the farming-pastoral ecotone in Northern China based on physical vulnerability assessment. The physical vulnerability curve was constructed from the relationship between drought hazard intensity index and yield loss rate. The risk assessment of agricultural drought was conducted from the drought hazard intensity index and physical vulnerability curve. The probability distribution of drought hazard intensity index decreased from south-west to north-east and increased from south-east to north-west along the rainfall isoline. The physical vulnerability curve had a reduction effect in three parts of the farming-pastoral ecotone in Northern China, which helped to reduce drought hazard vulnerability on spring maize. The risk of yield loss ratio calculated based on physical vulnerability curve was lower compared with the drought hazard intensity index, which suggested that the capacity of spring maize to resist and adapt to drought is increasing. In conclusion, the farming- pastoral ecotone in Northern China is greatly sensitive to climate change and has a high probability of severe drought hazard. Risk assessment of physical vulnerability can help better understand the physical vulnerability to agricultural drought and can also promote measurements to adapt to climate change. [ABSTRACT FROM AUTHOR]

As global surface temperature continues to rise, increasing evidences have shown that social and natural systems are deeply influenced by climate change. The government and farmers' awareness, as well as measures to adapt to these climate-driven changes, are critical for local sustainable development. In this study, we established a conceptual model of the relationship among human adaptation, development demand and environment changes to analyze the mechanism of agricultural drought adaptation based on an empirical research at the famer and government level. These results show that under the impact of climate change, the study area of drought risk has continued to expand. With this condition, the government and farmers have constantly taken measures to control the development demand and adjust to environmental changes in order to adapt to agricultural drought. Interactions among environmental changes, development demand and adaptation measures have kept the regional nature-society-economy compound ecosystem in dynamic balance. In addition, the effect of these adaptation measures always has an inertia that may induce a longer and deeper impact on the region, which is considered when making adaptation strategies. Rainfed areas are considered to be the most sensitive and unstable to environment change. This study reveals the mechanism of adaptation from a macroscopic perspective and may provide some references on measures and strategies for drought adaptation in other rainfed areas. [ABSTRACT FROM AUTHOR]

Climate change is affecting every aspect of human activities, especially the agriculture. In China, extreme drought events caused by climate change have posed great threaten to food safety. In this work we aimed to study the drought risk of maize in the farming-pastoral ecotone in Northern China based on physical vulnerability assessment. The physical vulnerability curve was constructed from the relationship between drought hazard intensity index and yield loss rate. The risk assessment of agricultural drought was conducted from the drought hazard intensity index and physical vulnerability curve. Results of the drought hazard intensity index showed that the risk of agricultural drought displayed a negative correlation with the precipitation and kept rising from 1966 to 2011. Risk assessments of yield loss ratio shows that physical vulnerability curve has magnify and reduce function to drought hazard. So improving the capacity of maize to resist drought can help them adapt to drought hazard. In conclusion, the farming-pastoral ecotone in Northern China had great sensitivity to climate change and high probability for severe drought hazard. Risk assessment of physical vulnerability can help better understanding the physical vulnerability to agricultural drought and can also promote measurements to adapt to the climate change. [ABSTRACT FROM AUTHOR]