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We extend the array theory to design 2D curved coding metasurfaces in order to achieve arbitrary wavefront control. The extended array theory establishes the relationship between wavefront and curved-surface, which provides a simple and effective method to obtain the layout of desired metasurfaces. According the theory, we present 2D curved metasurfaces with 3-bit coding elements. Both simulations and measurements demonstrate that the proposed designs can manipulate wavefront effectively. For normal incidence, the aperture efficiency of normal reflection is more than 90%. For general oblique incidence, the proposed designs almost meet the expectances, but the aperture efficiency decreases with the increase of desired scattering elevation angle. The curved coding metasurfaces are expected to be applied to many devices such as conformal antenna array.

BACKGROUND: Peroxisome proliferators-activated receptors γ (PPARγ) and secreted frizzled related protein 5 (SFRP5) are abnormally expressed in liver cells. But their role in the transformation of non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH) remains to be studied. We aimed to explore the role of S-nitrosylation (SNO) in the conversion of NAFL to NASH via the peroxisome PPARγ/SFRP5 pathway. METHODS: A normal diet and methionine-choline deficient diet were used to construct the NAFL and NASH mouse models, respectively. The differences between the SNO of PPARγ in both models were measured by irreversible biotinylation. Quantitative reverse transcription PCR (qRT-PCR) and Western blotting were used to detect the effect of SNO on the expression of PPARγ messageRNA (mRNA) and protein in L02 hepatocytes. Nubiscan software, luciferase reporter gene, and chromatin immunoprecipitation assay (CHIP) were used to verify the targeting relationship between PPAR and SFRP5. The expression of tumor necrosis factor α (TNFα), interleukin-1β (IL-1β), and interleukin-6 (IL-6), which are indicators for the activation of Kupffer cells, were determined by enzyme linked immunosorbent assay (ELISA) after co-cultivation of L02 hepatocytes and Kupffer macrophages, as well as the exogenous regulation of SNO, PPARγ, and SFRP5 in hepatic L02 cells. RESULTS: The NAFL and NASH mouse models were successfully constructed, and the level of PPARγ SNO in the NAFL model was significantly lower than the NASH model (P

An extraction method for the equivalent electromagnetic parameters (EEP) of grading honeycomb absorbing materials (GHAM) is proposed based on the asymmetric property of GHAM, EEP was modified by gradient factors related to its physical parameters in this paper. Considering that the strength of electromagnetic wave loss is dominated by the imaginary part of the complex dielectric constant, the EEP extraction method is built by optimizing the imaginary part of the complex dielectric constant according to the GHAM’s physical properties, such as the coating thickness of each layer for the GHAM, the increment between two adjacent gradient coatings, the layers of the GHAM, and the total axial height of graded honeycomb. The GHAM were prepared by the immersion process, and the reflectance measured by the free space method was consistent with that calculated by the EEP extraction method proposed in this paper within 2–18 GHz. The proposed EEP extraction method is simple, convenient, high precision, and it has played a certain role in solving the problems in actual engineering applications.

The formation of complex fracture networks through the fracturing technology is a crucial operation used to improve the production capacity of tight gas/oil. In this study, physical simulation experiments of hydraulic fracturing were conducted with a true triaxial test system on cubic shale oil samples from the Yanchang Formation, China. The fractures were scanned by CT both before and after the experiments and then reconstructed in 3D. The complexity of fracture networks was investigated quantitatively by the fractal theory with topology. Finally, the effect of the horizontal stress ratio, fluid viscosity, and natural fractures on the complexity of the fracture networks was discussed. The results indicate that the method based on fractal theory and topology can effectively characterize the complexity of the fracture network. The change rates of the fractal dimension (K) are 0.45–3.64%, and the fractal dimensions (DNH) of the 3D fracture network after fracturing are 1.9522–2.1837, the number of connections per branch after fracturing (CB) are 1.57–2.0. The change rate of the fractal dimension and the horizontal stress ratio are negatively correlated. However, the change rate of the fractal dimension first increases and then decreases under increasing fluid viscosities, and a transition occurs at a fluid viscosity of 5.0 mPa·s. Whether under different horizontal stress ratios or fluid viscosities, the complexity of the fracture networks after fracturing can be divided into four levels according to DNH and CB. Complex fracture networks are more easily formed under a lower horizontal stress ratio and a relatively low fluid viscosity. A fracturing fluid viscosity that is too low or too high limits the formation of a fracture network.

Expanded newborn screening facilitates early identification and intervention of patients with inborn errors of metabolism (IEMs), There is a lack of disease spectrum data for many areas in China. To determine the disease spectrum and genetic characteristics of IEMs in Xi'an city of Shaanxi province in northwest China, 146152 newborns were screening by MSMS from January 2014 to December 2019 and 61 patients were referred to genetic analysis by next generation sequencing (NGS) and validated by Sanger sequencing. Seventy-five newborns and two mothers were diagnosed with IEMs, with an overall incidence of 1:1898 (1:1949 without mothers). There were 35 newborns with amino acidemias (45.45%, 1:4176), 28 newborns with organic acidurias (36.36%, 1:5220), and 12 newborns and two mothers with FAO disorders (18.18%; 1:10439 or 1:12179 without mothers). Phenylketonuria and methylmalonic acidemia were the two most common disorders, accounting for 65.33% (49/75) of all confirmed newborn. Some hotspot mutations were observed for several IEMs, including PAH gene c.728G>A for phenylketonuria; MMACHC gene c.609G>A and c.567dupT, MMUT gene c.323G>A for methylmalonic acidemia and SLC25A13 gene c.852_855del for citrin deficiency. Our study provides effective clinical guidance for the popularization and application of expanded newborn screening, genetic screening, and genetic counseling of IEMs in this region.

Stroke patients under the background of the new crown epidemic need to be home-based care. However, traditional nursing methods cannot take care of the patients’ lives in all aspects. Based on this, based on machine learning algorithms, our work combines regression models and SVM to build a smart wearable device system and builds a system prediction module to predict patient care needs. The node is used to collect human body motion and physiological parameter information and transmit data wirelessly. The software is used to quickly process and analyze the various motion and physiological parameters of the patient and save the analysis and processing structure in the database. By comparing the results of nursing intervention experiments, we can see that the smart wearable device designed in this paper has a certain effect in stroke care.

Additional file 4: Figure S1. Phylogenetic profiles of urine microbes among stone UR and tumor UR and controls. (A, D) The microflora composition abundance of each sample at the phylum level (A) and genus level (D). (B, E) Composition of the urine microbiota at the phylum level (B) and genus level (E) among three groups. (C) The 5 different phylum profiles of average relative abundance across three groups tested by the Wilcoxon rank sum test. The dark green star indicates q

Additional file 5: Figure S2. LEfSe analyses of the urine microbiomes of stone UR and tumor UR patients compared to those of controls. (A) The LDA bar graphs show differential abundance between stone UR and controls. (B) The LDA bar graphs show differential abundance between tumor UR and controls.

Additional file 3: Table S3. PERMANOVA tests of the urine microbiota at different dissimilarity distances.

The Dongsheng gas field is characterized by low porosity and low permeability. Its principal producing reservoir is the H-1 zone, belonging to the Lower Shihezi Formation. Sand is the main lithology in the H-1 zone, while mud interlayers are also well developed in a vertical direction. As a result, the reservoir is a sand-mud interbed, which brings difficulty to fracture height extension. In order to understand the process of fracture height growth in a sand-mud interbed reservoir and obtain the responses of injection pressure and fracture width during a hydraulic fracturing, a hydromechanical-coupled model is established. Mud interlayers are fully considered and a cohesive zone model is adopted to deal with fracture propagation. Numerical results show that the fracture extends quickly to the sand-mud interface after initiation and breaks through rather than propagating along the interfaces. Pressure and width both increase continuously when fracture propagates in the mud interlayer. High-viscosity and high-injection rates are helpful for the fracture to break through the mud interlayer, especially at an early period. When the mud interlayers are asymmetric, pressure and width fluctuate several times once fracture propagates inside and breaks through the mud interlayer. Perforations close to the thinner mud interlayer can increase the fracture width and reduce fracturing risks.

To describe the fracture width is crucial for the flow conductivity evaluation, which influences the exploitation efficiency of unconventional oil and gas resources. Commonly, as the proppants fill in the fracture, the deformation will happen under the closure pressure to resist the fracture width change. Therefore, it is significant to develop the theoretical model to predict the variation. In this work, the mathematical model for the propping behavior of proppants in the fracture under closure pressure is established based on the Hertz contact theory. Compared with the existing models, the developed model considers both the proppant insertion and the elastic compression among the proppants, which is closer to the actual physical process. Furthermore, the experimental cases with different proppant sizes are taken to verify the model, and the good conformity presents its rationality. The parameter sensitivity analysis of this model shows that the fracture width change increases with the increase of the average diameters of proppants ( D ) and it declines with the improving of proppant elasticity modulus ( E 1 ) and Poisson’s ratio ( v 1 ).

Additional file 6: Figure S3. A random forest model was established to distinguish stone UR from tumor UR based on microbial genus. (A, B, C) 8, 8 and 1 genus were selected as the optimal marker set for the three ‘randomForest’ model respectively (A: controls vs stone UR; B: controls vs tumor UR; C: stone UR vs tumor UR). (D) The average AUC value after 100 ROC measurements to distinguish two types of UR. (E) The MDA of this marker between stone UR and tumor UR. (F) The probability of tumor UR value between two types of obstructive UR.

Additional file 9: Figure S4. Microbial function profiles of these UR patients and the control subjects. (A) PCOA analysis for the relative abundance of level 2 COG categories of all participants. (B) A total of 18 COG functions were significantly different among three groups. (C) Heatmap of Spearman’s correlation of the 44 significantly different genera and 18 significantly different pathways among three groups. The genera or pathways that were enriched in controls are shown in blue.

Several air pollution episodes occurred in Beijing before and after the 2014 Asia-Pacific Economic Cooperation (APEC) summit, during which air-pollution control measures were implemented. Within this autumn-winter transit season, domestic heating started. Such interesting period merits comprehensive chemical characterization, particularly the organic species, to look into the influence of additional heating sources and the control measures on air pollution. Therefore, this study performed daily and 6h time resolved PM2.5 sampling from the 24th October to 7th December, 2014, followed by comprehensive chemical analyses including water-soluble ions, elements and organic source-markers. Apparent alterations of chemical profiles were observed with the initiation of domestic heating. Through positive matrix factorization (PMF) source apportionment modeling, six PM2.5 sources including secondary inorganic aerosol (SIA), traffic emission, coal combustion, industry emission, biomass burning and dust were separated and identified. Coal combustion was successfully distinguished from traffic emission by hopane diagnostic ratio. The result of this study reveals a gradual shift of dominating sources for PM pollution episodes from SIA to primary sources after starting heating. BaPeq toxicity from coal combustion increased on average by several to dozens of times in the heating period, causing both long-term and short-term health risk. Air mass trajectory analysis highlights the regional influence of the industry emissions from the area south to Beijing. Control measures taken during APEC were found to be effective for reducing industry source, but less effective in reducing the overall PM2.5 level. These results provide implications for policy making regarding appropriate air pollution control measures.

Several air pollution episodes occurred in Beijing before and after the 2014 Asia-Pacific Economic Cooperation (APEC) summit, during which air-pollution control measures were implemented. Within this autumn-winter transit season, domestic heating started. Such interesting period merits comprehensive chemical characterization, particularly the organic species, to look into the influence of additional heating sources and the control measures on air pollution. Therefore, this study performed daily and 6h time resolved PM

sua-CMS (cytoplasmic male sterility) is the only male sterile system in tobacco breeding, but the mechanism of abortion is unclear. Cytological characteristics show that abortion in the sua-CMS line msZY occurs before the differentiation of sporogenous cells. In this study, a comparative transcriptomic analysis was conducted on flower buds at the abortion stage of msZY and its male fertile control ZY. A total of 462 differentially expressed genes were identified in msZY and ZY, which were enriched via protein processing in the endoplasmic reticulum (ER), oxidative phosphorylation, photosynthesis, and circadian rhythm-plant by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Most genes were downregulated in the ER stress pathway, heat-shock protein family, F1F0-ATPase encoding by the mitochondrial genome, and differentiation of stamens. Genes in the programmed cell death (PCD) pathway were upregulated in msZY. The transcriptome results were consistent with those of qRT-PCR. Ultrastructural and physiological analyses indicted active vacuole PCD and low ATP content in msZY young flower buds. We speculated that PCD and a deficiency in ATP synthesis are essential for the abortion of sua-CMS. This study reveals the potential mechanism of abortion of tobacco sua-CMS.

Tobacco (Nicotiana tabacum) is considered as the model plant for alkaloid research, of which nicotine accounts for 90%. Many nicotine biosynthetic genes have been identified and were known to be regulated by jasmonate-responsive transcription factors. As an important regulator in plant physiological processes, whether small RNAs are involved in nicotine biosynthesis is largely unknown. Here, we combine transcriptome, small RNAs and degradome analysis of two native tobacco germplasms YJ1 and ZY100 to investigate small RNA’s function. YJ1 leaves accumulate twofold higher nicotine than ZY100. Transcriptome analysis revealed 3,865 genes which were differently expressed in leaf and root of two germplasms, including some known nicotine and jasmonate pathway genes. By small RNA sequencing, 193 miRNAs were identified to be differentially expressed between YJ1 and ZY100. Using in silico and degradome sequencing approaches, six nicotine biosynthetic genes and seven jasmonate pathway genes were predicted to be targeted by 77 miRNA loci. Three pairs among them were validated by transient expression in vivo. Combined analysis of degradome and transcriptome datasets revealed 51 novel miRNA-mRNA interactions that may regulate nicotine biosynthesis. The comprehensive analysis of our study may provide new insights into the regulatory network of nicotine biosynthesis.

Background Obesity is a principal risk factor for the development of type 2 diabetes and cardiovascular diseases. Natural plants and/or foods play an important role in the management of obesity. Acalypha australis L. (AAL) is a kind of potherb popular among Asian populations, and it is also consumed as a food ingredient and traditional herbal medicine. Objective We investigated the effects of water extract from AAL on high-fat-diet (HFD)-induced obese mice and 3T3-L1 adipocytes to develop a new functional food material. Design Nine-week-old male mice were randomly divided into control (chow diet, n = 6) and HFD (n = 30) group. From 12-weeks onward, mice in the HFD group were further separated into model (saline, 6 mL/kg), simvastatin (0.11 mg/mL, 6 mL/kg), and AAL treatment (low, middle, and high dosage: 300, 600, and 900 mg/kg) group, with 6 animals per group, while mice in the control group were treated with saline (6 mL/kg). Food intake, body/fat weight, liver/kidney indexes, and lipid profiles were determined. Tissues were fixed with formalin for pathological examination. Western blotting and PCR were performed to evaluate the protein and mRNA expression in 3T3-L1 adipocytes. Oil Red O staining was used to determine lipid accumulation. Results AAL administration significantly suppressed body weight gain, and reduced fat pad weight and Lee’s index in obese mice, but had no effect on liver/kidney index. AAL also reduced serum cholesterol, triglyceride, and LDL-C and increased HDL-C levels. Histological analysis revealed that AAL significantly ameliorated lipid accumulation in the liver and subcutaneous adipose tissue. In vitro, Oil Red O staining showed that AAL inhibited adipose differentiation by down-regulating the gene and protein expression of PPARγ and C/EBPα. AAL also reversed HFD-induced intestinal dysbacteriosis. Conclusion AAL water-soluble extract has a significant anti-adipogenic effect in the HFD-induced obese mice model.

A novel polarized reflectarray is designed, fabricated, and experimentally characterized to show its flexibility and efficiency to control wave generation and focusing of orbital angular momentum (OAM) vortices with desirable OAM modes in the microwave frequency regime. In order to rigorously study the generation and focusing of OAM, a versatile analytical theory is proposed to theoretically study the compensation phase of reflectarray. Two prototypes of microwave reflectarrays are fabricated and experimentally characterized at 12 GHz, one for generation and one for focusing of OAM-carrying beams. Compared with the OAM-generating reflectarray, the reflectarray for focusing OAM vortex can significantly reduce the beam diameter, and this can further improve the transmission efficiency of the OAM vortex beams. We also show that the numerical and experimental results agree very well. The proposed design method and reflectarrays may spur the development of new efficient approaches to generate and focus OAM vortex waves for applications to microwave wireless communications., Comment: 10 pages, 10 figures

The continuum-based discrete element method was applied to probe 3D hydrofracturing behaviours. The interaction between hydrofracturing cracks and pre-existing fractures was modelled. Glutenite, a typical heterogeneous rock, was numerically reconstructed using physical parameter tests, computed tomography and imaging processing methods. The effect of pre-existing fractures on hydrofracture propagation was characterized, and the effects of material heterogeneity and horizontal in situ stress differences on fracturing were characterised using fractal theory. Investigation of hydraulic fracture (HF) propagation in heterogeneous rock, and of the mechanism by which complex hydrofracturing crack networks form through numerical simulation, revealed four typical influencing factors. These four, namely mineral particles, in situ stress difference, natural fracture (NF) density, and NF aperture inside the glutenite, were analysed to determine their effect on the HF propagation pattern, and the mechanism of complex fracture network formation in glutenite was determined. A 3D fractal dimension was proposed to characterize the spatial distribution of complex fracture networks. With increasing aperture and density of NFs, the hydrofracturing crack network becomes more complex. Mineral particles hinder the propagation of HFs; analogously, the higher the volume percentage of mineral particles is; the more complex is the hydrofracturing crack network that forms. The HFs generate and propagate near the bilateral tips of the NFs. The HFs will propagate along the direction of maximum horizontal in situ stress, and they are prone to turn into a single crack with greater in situ stress difference. The 3D fractal dimensions were computed and quantitatively reflected the above phenomena.

Magnetic loss materials have been extensively used as surface waves attenuation materials. Transmission characteristics of surface waves in defective absorbing layers were rarely reported. Herein, the transmission attenuation of surface waves on defective flexible magnetic loss-absorbing materials had been studied extensively. By comparison, the transmission performance of the surface wave on materials with defects was obviously deteriorated. The results demonstrated that the slot length was less than half the wavelength of the incident plane wave, the defect did not matter on the monostatic radar cross section. Once the length was larger than half wavelength, the scattering of the surface wave was obvious. Non-specular scattering occurs at the defects, causing an increase in the radar cross section. In order to further reduce the radar cross section caused by non-specular scattering, some effective repair schemes would be needed.

In this paper, a typical three-layer structure — metal/dielectric/patterned metal element surface is presented. The unit cell of the metasurface is composed of rectangular patch element. Based on the generalized laws of reflection, by discontinuous phase difference, abnormal reflection is realized. The thickness of the dielectric substrate is 3 mm. By calculating and optimizing the length and width of the patch element, 12 basis elements are selected, and the phase difference is 30 degrees. The reflection amplitude of every element is greater than 0.9. Based on the patch elements, a supercell that is arranged in a 12 by 12 array is realized. The size of the metasurface is 180 mm × 180 mm. Under normal incidence, at 5 GHz, the main lobe is deflected about negative 41 degrees away from the normal direction as was expected. Thereby, the main lobe of the mirror is effectively suppressed. The directional scattering properties of the proposed matesurface when environment temperature is high are also considered. The environmental temperature affects the electromagnetic parameters of the pattern layer and the dielectric layer. The simulation is performed and the results show an acceptable agreement with the numerical calculation. Metasurfaces realized with rectangular patch have the advantages in design and manufacture.

The shale gas exploration and development in Sichuan Basin had achieved a major breakthrough remarkably. However, the business development focused on the marine shale gas in shallow layers (vertical depth 3500 m) business development in Wufeng Formation-Longmaxi Formation is the key to the rapid growth of shale gas production in the Sichuan Basin. In the literature, authors analyzed the geological characteristics of the deep shale gas of the Wufeng Formation - Longmaxi Formation in southern Sichuan Basin through particular dissection and analysis of deep wells in comparison to the shallow layers. The thickness of organic-rich shale in the deep region of southern Sichuan Basin measures to be more than 120 m, which is larger than that of the shallow layers in Fuling area. The vertical TOC change remains constant whereas the thickness of high-quality shale is approximately forty meters in both regions. Nevertheless, the RO is higher in the deep region of southern Sichuan Basin. The calcareous content of the organic shale increases while the silicon content decreases from the Fuling area down as it gets deeper into the region in southern Sichuan Basin. It is quite evident in research that the shales in the Wufeng Formation – Longmaxi Formation of the deep to shallow layers of southern Sichuan that there are not many differences in depositional environment, lithology, TOC, etc. However, there are four major differences: (1) The porosity of shale in the deep region of southern Sichuan Basin is higher than that in Fulin gas field due to the corrosion pore. (2) The gas-bearing properties are better in the deep regions of southern Sichuan Basin because they have better preservation condition compared to that of the shallow region of Fuling. (3) However, gas-bearing properties are worse in the local region of stronger structure deformation and the basin boundary fault zone. (4) The shale gas resources in the deep regions of southern Sichuan Basin are great and have wide prospects for exploration and development. In order for a breakthrough to be generated in deep shale gas commercial development in the soonest possible time, authors propose the following: utilize strengthening evaluation of small layer contrasting so as to explain fine structure and predict fracture; strengthen the research on drilling and fracturing technology for deep shale gas; strengthen research on wells column; and support technology for efficient production of shale gas. Keywords: Sichuan basin, Lower Silurian, Longmaxi formation, Deep shale gas, Marine facies

Metallo-β-lactamases (MBLs), such as New Delhi metallo-β-lactamase (NDM-1) have spread world-wide and present a serious threat. Expression of MBLs confers resistance in Gram-negative bacteria to all classes of β-lactam antibiotics, with the exception of monobactams, which are intrinsically stable to MBLs. However, existing first generation monobactam drugs like aztreonam have limited clinical utility against MBL-expressing strains because they are impacted by serine β-lactamases (SBLs), which are often co-expressed in clinical isolates. Here, we optimized novel monobactams for stability against SBLs, which led to the identification of LYS228 (compound 31). LYS228 is potent in the presence of all classes of β-lactamases and shows potent activity against carbapenem-resistant isolates of Enterobacteriaceae (CRE).

To investigate the organic composition and their sources of very fine atmospheric particulate matter (PM), size-segregated PM was sampled using rotating drum impactor (RDI) in series with a sequential filter sampler in Augsburg, Germany, from April 2014 to February 2015. Organic speciation analysis and organic carbon/elemental carbon (OC/EC) analysis was performed for the smallest size fraction PM0.36 (PM

A continuous daily PM2.5 sampling campaign from 10 April till 8 June 2013, including three haze episodes, was conducted in Beijing. Chemical species, including EC, OC, water-soluble ions and inorganic elements, were analysed by a thermal/optical carbon analyser, IC and ICP-MS, respectively. A comparison of air quality during such haze episodes in relation to clear air situations, as well as the differences between the haze episodes was emphasised. The results showed that the most important fractions of PM2.5 during haze were SO42−, NO3− and NH4+ (namely, SNA) which together accounted for 54–61% of the total PM2.5 mass. Estimated secondary organic carbon (SOC) was also found to be increased during haze, but the relative increase compared to clear days was much lower than for SNA, leading to a decrease in relative contribution of SOC to PM2.5 in the observed haze events. Cluster analyses from back trajectories showed four air mass clusters during spring 2013 and air flow, which was from the south-easterly directions, might favour the accumulation of PM2.5, especially SNA and anthropogenic elements. All these results proved that the anthropogenic air pollution in the Southeast of Beijing was responsible for the formation of hazes in Beijing during spring 2013.

Under the current environment of low oil price, surfactant enhanced oil recovery technology is more economic and feasible without changing fracturing technology and adding special equipment. Surfactant enhanced oil recovery is induced by decreasing interfacial tension and changing wettability. However, there are many kinds of surfactant, and the reservoir conditions and rock types are different, so the first requirement of enhanced oil recovery is to select the surfactant which is suitable for the target reservoir. In view of the characteristics of high temperature and high salinity in inter-salt shale reservoir, in this paper, several surfactant types were selected and negative/non-composite surfactants were screened out by taking the adhesion work reduction factor related to imbibition resistance as the main index. This study is of practical significance for hydraulic fracturing reservoirs with surfactant enhanced oil recovery technology.

One of the current challenges in the development of swarm robots is making them realize obstacle avoidance while keeping formation. This paper proposes a new obstacle avoidance method for multiple robots based on the aggregation and disaggregation approach. First, the formation-based multi-resolution models of swarm robots are presented and the formation attribute-based consistency mapping functions are designed. Then, obstacle avoidance behavior based on aggregation and disaggregation method is presented and the basic obstacle avoidance behaviors are designed. Finally, the simulation results are presented to show the feasibility of the proposed method.

Anisotropy is prevalent in sedimentary rock masses, such as shale formations that contain numerous inherent bedding planes (BPs) and natural fractures (NFs). This study proposes a new methodology to determine the equivalent elastic properties of shale formations that uses the weak patches stiffness model and fracture mechanics theory to theoretically consider both BP- and NF-induced anisotropy. First, a series of uniaxial compression tests for Longmaxi shale demonstrates that its apparent elastic modulus ranges from 14.9 to 18.8 GPa. Then, by collecting experimental data and performing a Monte–Carlo simulation method, the NF network is built within the target 3D shale formation, and the equivalent elastic modulus values along a given wellbore wall are estimated. The results reveal that the elastic parameters of shale formations exhibit high directional dependency associated with the presence of BPs and NFs; a higher NF density is also found to lower the BP-induced anisotropy. Wider application of Monte–Carlo simulations in future studies is recommended to calculate the deformation issues of large-scale numerical petroleum engineering modeling when considering the influence of NFs.

To systematically review the clinical outcomes of surfactant administration via a thin endotracheal catheter during spontaneous breathing compared with conventional administration involving tracheal intubation, mechanical ventilation (MV), and tracheal extubation, in preterm infants. PubMed, EMBASE, and the Cochrane Library were searched to identify relevant clinical trials. Data were analyzed using the Cochrane Collaboration methods. Primary outcome measures included the incidence of MV and bronchopulmonary dysplasia (BPD). Finally, four RCTs, two prospective cohort trials, and six historical controlled trials involving 5,261 preterm infants were analyzed. In RCTs, surfactant administration though a thin catheter reduced the incidence of MV (risk ratio [RR]: 0.74; 95% confidence interval [CI]: 0.66, 0.81) in 72 hr and BPD (RR: 0.69, 95%CI: 0.50, 0.97) compared with conventional administration and in non-RCTs, there was also significant reduction in the incidence of MV (RR: 0.55, 95%CI: 0.45, 0.68) and BPD (RR: 0.70, 95%CI: 0.60, 0.82) in favor of the thin catheter group. There were no significant differences between the two procedures in terms of short-term pulmonary complications, intracranial pathology, necrotizing enterocolitis, retinopathy of prematurity, and mortality. Thus, surfactant administration via a thin endotracheal catheter to preterm infants has promising benefits, including reducing the incidences of MV and BPD, while providing comparable breathing support to conventional administration in MV. Pediatr Pulmonol. 2017; 52:844-854. © 2017 Wiley Periodicals, Inc.

Elevated atmospheric CO2 (eCO2) is anticipated to have marked effects on soil microbial populations. While there is experimental evidence to support this view there are also studies where changes in microbial populations, such as the abundance of bacteria, are suggested but cannot be statistically established. We conducted this study to identify whether the sampling and sample treatment methods used could influence the results obtained using bacterial abundance as the variable of interest. We tested three different sampling methods and two different DNA extraction kits. The first because microbes are distributed heterogeneously in soil so the sampling procedure might be expected to influence the accuracy and precision of the population estimate and the second because the quantity and quality of DNA extracted influences the microbial analyses that can be performed and can introduce bias. Samples were taken from a long-running FACE experiment on grassland from under plants ofAgrostis capillaris. We found that bacterial abundance was consistently lower under eCO2 but we were only able to establish a statistical difference where a more intense sampling regime was used and bulking of the soil sample was avoided. A reduction in bacterial abundance is a consistent outcome in eCO2 field experiments but the only other occasion where this reduction has been found to be significant was also where individual soil cores were analysed rather than the samples being bulked. We conclude that while there is extra work and cost attached to more detailed sampling this approach is highly desirable if we are to make robust conclusions about the impacts of eCO2 on soil microbes.

Background The sensitivity of endoscopy in diagnosing chronic atrophic gastritis is only 42%, and multipoint biopsy, despite being more accurate, is not always available. Aims This study aimed to construct a convolutional neural network to improve the diagnostic rate of chronic atrophic gastritis. Methods We collected 5470 images of the gastric antrums of 1699 patients and labeled them with their pathological findings. Of these, 3042 images depicted atrophic gastritis and 2428 did not. We designed and trained a convolutional neural network-chronic atrophic gastritis model to diagnose atrophic gastritis accurately, verified by five-fold cross-validation. Moreover, the diagnoses of the deep learning model were compared with those of three experts. Results The diagnostic accuracy, sensitivity, and specificity of the convolutional neural network-chronic atrophic gastritis model in diagnosing atrophic gastritis were 0.942, 0.945, and 0.940, respectively, which were higher than those of the experts. The detection rates of mild, moderate, and severe atrophic gastritis were 93%, 95%, and 99%, respectively. Conclusion Chronic atrophic gastritis could be diagnosed by gastroscopic images using the convolutional neural network-chronic atrophic gastritis model. This may greatly reduce the burden on endoscopy physicians, simplify diagnostic routines, and reduce costs for doctors and patients.

Background and aims Insulin-like growth factor (IGF)-1 deficiency is associated with a range of metabolic disorders. Cyclic glycine-proline (cGP) is a natural nutrient and regulates the amount of active IGF-1 in plasma. Plasma cGP decreases in hypertensive women whereas increases in obese women, suggesting its involvement in cardio-metabolic function. We therefore examined the effects of cGP on metabolic profiles and blood pressure in high-fat diet (HFD)-induced obese male rats. Methods Male rats were fed either a HFD or a standard chow diet (STD) ad-libitum from 3 to 15 weeks of age. Rats were administered either saline or cGP from 11 to 15 weeks of age. At 14 weeks of age, systolic-blood pressure (SBP) was measured by tail-cuff plethysmography and body composition quantified by DEXA. Blood and retroperitoneal fat tissues were collected. Plasma concentrations of insulin, IGF-1, IGF binding protein (IGFBP)-3 and cGP were evaluated using ELISA and HPLC-MS respectively. Results Compared to STD, HFD feeding increased SBP, total fat mass and fat/lean ratio, retroperitoneal fat weight, fasting plasma insulin and cGP concentrations whereas decreased plasma IGF-1 and IGFBP-3 concentrations. Administration of cGP reduced SBP and retroperitoneal fat weight, but had no effect on body composition and plasma insulin concentrations. Conclusion HFD-associated decreases in IGFBP-3 and increases in cGP represent an autocrine response to normalize IGF-1 function through improving the amount of bioavailable IGF-1 in the circulation of obese male rats. The beneficial effects of cGP on SBP and retroperitoneal fat mass may suggest a therapeutic potential for cGP in HFD-associated cardio-metabolic complications.

Alterations to the gut microbiota have been previously suggested to be tightly linked to chronic systemic inflammation, which is a major contributing factor to complications and disease progression in chronic kidney disease (CKD). Nevertheless, the effect of gut dysbiosis on the pathogenesis and/or production of inflammatory factors in CKD has not been extensively studied to date. In the present study, we conducted 16S ribosomal DNA pyrosequencing using fecal microbiota samples and analyzed the production of serum inflammatory factors in 50 patients with CKD and 22 healthy control (HC) subjects. The results revealed that compared to the HC subjects, patients with CKD exhibited a significant reduction in the richness and structure of their fecal microbiota. At the phylum level, compared to the HC group, patients with CKD also presented reduced abundance of Actinobacteria but increased abundance of Verrucomicrobia. Moreover, the genera Lactobacillus, Clostridium IV, Paraprevotella, Clostridium sensu stricto, Desulfovibrio, and Alloprevotella were enriched in the fecal samples of patients with CKD, while Akkermansia and Parasutterella were enriched in those of the HC subjects. The abundance of Akkermansia in the CKD group was significantly lower than that in the HC group (3.08 vs. 0.67%); this decrease in the abundance of Akkermansia, an important probiotic, in patients with CKD is a striking discovery as it has not been previously reported. Finally, we analyzed whether these changes to the fecal microbiota correlated with CKD clinical characteristics and/or the production of known inflammatory factors. Altered levels of the microbiota genera Parasutterella, Lactobacillus, Paraprevotella, Clostridium sensu stricto, and Desulfovibrio were shown to be correlated with CKD disease-severity indicators, including the estimated glomerular filtration rate. Most notably, Akkermansia was significantly negatively correlated with the production of interleukin-10. The results of the present study suggest that microbiota dysbiosis may promote chronic systemic inflammation in CKD. Furthermore, they support that modifying the gut microbiota, especially Akkermansia, may be a promising potential therapeutic strategy to attenuate the progression of, and/or systemic inflammation in, CKD.

In this paper, a high-efficiency and wideband converter based on a petal metasurface is proposed. This polarization converter can convert the linearly polarized incident electromagnetic wave to its orthogonal counterpart upon the reflection mode at resonance frequencies of 7.55 GHz, 14.15 GHz, 22.23 GHz, and at these three frequencies, the cross-polarization coefficient is almost 100%. The efficiency of the converter is higher than 90% from 6.81 GHz to 23.03 GHz. Moreover, its parameters of periodic and thickness are tunable. The physical mechanism is revealed by further analysis. Such a scheme of the linear polarization converter has potential applications in microwave communications, remote sensing, and imaging.

Elucidating the genetic architecture underlying autism spectrum disorder (ASD) will aid in the understanding of its genetic etiology and clinical diagnosis. A comprehensive set of coding de novo variants (DNVs) from 4504 trios with ASD and 3012 control/sibling trios from several large-scale sequencing studies were collected and combined. Multiple in-depth analyses including DNVs burden, clinical phenotypes, and functional networks underlying the combined data set were used to evaluate the nonrandom occurrence of multiple extreme DNVs (loss-of-function and damaging missense variants) in the same patients. We observed a significant excess of multiple extreme DNVs among patients with ASD compared with controls. Meanwhile, patients with ASD carrying 2+ extreme DNVs had significantly lower IQs than patients carrying 0 or 1 DNV. Moreover, much closer functional connectivity than expected was observed among 2 or more genes with extreme DNVs from the same individuals. In particular, we identified 56 key genes as more confident ASD genes compared with other known ASD genes. In addition, we detected 23 new ASD candidate genes with recurrent DNVs, including VIP, ZWILCH, MSL2, LRRC4, and CAPRIN1. Our findings present compelling statistical evidence supporting an oligogenic model and provide new insights into the genetic architecture of ASD.

Under the background of the fiery development of MOOC construction and the need for professional development of teachers, this article fully displays the current situation of MOOCs promotion of teachers' professional development. On the basis of this and the application of "Data Processing and Tool Application in Teaching Research" this article puts forward the trinity strategy which aims is to coordinate the frontline teachers, with the education department, as well as the MOOC construction team. It promotes teachers' professional development with the objective for teachers to improve specialty development levels in the period of MOOC.

The promote trend of K-12 science education of improving comprehensive quality through science curriculum integration has been formed. STEAM education receives attention with the integration of the concept of interdisciplinary integration. This paper analyzed the practice of science curriculum in China and the research status of STEAM-based teaching model domestic and overseas. Meanwhile it adopts action research constructing the STEAM-based K-12 science curriculum instructional design model to further verify the validity. The model is certified to improve students' scientific knowledge, scientific quality, interdisciplinary integration ability and creative thinking through the instructional design and practice research.

In this paper, the design of a three-layer linear polarization converter based on substrate-integrated waveguide (SIW) technology is demonstrated. The transmission-type polarization converter with dual frequency polarization conversion characteristics is realized by a square-slot sandwiched by two layers of off-center dipole-slot resonator, and its asymmetric transmission (AT) property can be obtained by rotating the upper and the lower dipole-slot resonator to form an interlaced layout. An excellent polarization conversion ratio (PCR) can be realized by integrating the traditional transmission-type polarization converter with an SIW, and its physical mechanism can be explicated by guided wave field theory. Experimental results are presented and compared with the simulation results, and they demonstrated that ultra-high PCRs of the presented polarization converter are 0.87 and 0.99 for the measurement at the working frequency of 7.34 GHz and the simulation at the working frequency of 7.6 GHz, respectively. The designed polarization converter has greatly expanded the application field of SIW technology.

High levels of salinity induce serious oxidative damage in plants. Flavonoids, as antioxidants, have important roles in reactive oxygen species (ROS) scavenging. In the present study, the tobacco R2R3 MYB type repressor, NtMYB4, was isolated and characterized. The expression of NtMYB4 was suppressed by salinity. Overexpression of NtMYB4 reduced the salt tolerance in transgenic tobacco plants. NtMYB4 repressed the promoter activity of NtCHS1 and negatively regulated its expression. Rutin accumulation was significantly decreased in NtMYB4 overexpressing transgenic plants and NtCHS1 RNAi silenced transgenic plants. Moreover, high H2O2 and O 2 - contents were detected in both types of rutin-reduced transgenic plants under high salt stress. In addition, exogenous rutin supplementation effectively scavenged ROS (H2O2 and O 2 - ) and improved the salt tolerance of the rutin-reduced transgenic plants. In contrast, NtCHS1 overexpressing plants had increased rutin accumulation, lower H2O2 and O 2 - contents, and higher tolerance to salinity. These results suggested that tobacco NtMYB4 acts as a salinity response repressor and negatively regulates NtCHS1 expression, which results in the reduced flavonoid accumulation and weakened ROS-scavenging ability under salt stress.

Myrothecine A, characterized from the extracts of myrothecium roridum strain IFB-E012, isolated as endophytic fungi found in the traditional Chinese medicinal plant Artemisia annua. Here we investigated its roles on anti-tumor and immune regulation in vitro. Dendritic cells (DCs) are the most potent antigen presenting cells in immune responses. Recent studies have indicated that miRNAs are indispensable in regulating the development, differentiation, maturation and function of DC. MiR-221, acted as an oncogene, is an important regulator in cancer development by binding to 3' untranslated regions (3' UTR) of target mRNA. Here, we investigated whether myrothecine A could inhibit cell proliferation in hepatocellular carcinoma (HCC) cell line SMMC-7721 by regulating miR-221. The HCC cells were treated with myrothecine A at different concentration, and the cell growth ability was measured by MTT assay. Then we observed whether myrothecine A could affect the maturation of DC by regulating miR-221. The HCC cell line was co-cultured with immature DC from mice bone marrow, and the levels of CD86 and CD40 was detected by FCM. Our results showed that myrothecine A could rescue miR-221-induced cell proliferation and influence the protein level of p27 by inhibiting the expression of miR-221. In addition, myrothecine A could enhance the expression of CD86 and CD40 by reversing the function of miR-221. Therefore, myrothecine A may be acted as an anti-tumor drug to promote the maturation of DC in the microenvironment of hepatocellular carcinoma.