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In the paper, a novel Intersecting Cortical Network Model (ICM) based adaptive pansharpening algorithm is proposed to solve the deficiency of spectral distortion and texture detail missing in the remote sensing image fusion. The Shuffled Frog Leaping Algorithm (SFLA) is used in the proposed method to adaptively optimize the ICM model parameters. The fitness function of SFLA is constructed by fusion evaluation index Q4 and SAM, which can generate the irregular optimal segmentation regions. Then, these regions are used to adaptively extract the detail information of the panchromatic image. Finally, the sharpened higher resolution image is obtained with the weighted details and the multispectral upsampling image. Experiments are carried out with the WorldView-2 and GF-2 high-resolution datasets. The experimental results shown that the proposed algorithm performs better compared with the existing pansharpening fusion methods both in the spectral preservation and spatial detail enhancement, which verifies the effectiveness of the algorithm.

The appropriate feature segmentation can further improve the remote sensing image registration. The paper proposes a novel adaptive region-based registration method for remote sensing image, which combines the PCNN segmentation and feature-based method. Specifically, the parameters of PCNN are adaptively optimized by the slime mould algorithm. The reference and the input image are matched by the similar regions of PCNN segmentation, which is insensitive to the geometric and photometric changes. Then, two images are registered by the regional matching. Since the segmentation regions of the PCNN agree with the human visual system, and more stable. The proposed method achieves better registration performance. Experimental results conducted on UAV and GaoFen-2 remote sensing image pairs indicate that the proposed method outperforms the SIFT, SURF, Harris-Laplace, MSER methods.

With large-scale industrial parks developing, concern regarding high evaporation and its spillover impacts on water environment and water ecology has grown significantly in recent years. However, it is hard for the traditional water audit to meet the needs of the collaborative management of water environment and water ecology based on evaporation (3E), which requires a multi-dimensional evaluation. The purpose of this paper is to accurately evaluate industrial parks' impact considering the water life-cycle. This paper proposes a systematic 3E water audit method that contains a logical framework and a comprehensive evaluation index system with five dimensions and 25 indexes, then applies it to a typical iron and steel industrial park in China. The results presented the 3E audit score of the Chengsteel IP as 89.91, suggesting comprehensive performance is good. The score and grade of every index, especially the quantity of water evaporation per ton of steel, were provided. This paper indicates that the new method developed can systematically evaluate the impact of industrial parks. In addition, our analysis highlights the different management strategies and practices that relieve the impacts of the whole water-use process on legal, eco-environmental, economic, social, and technical dimensions.

AimsTobacco (Nicotiana tabacum) is an economically important crop. Root rot caused by Fusarium oxysporum has become a damaging disease in N. tabacum crops grown in Henan province of China. Therefore, the objectives of this study were to screen bacterial isolates against F. oxysporum from rhizosphere soils of tobacco growing areas and to evaluate their antifungal activities, biocontrol effects, and effects on plant growth.Methods and resultsNineteen strains with antifungal inhibition effects of >60% against F. oxysporum were obtained using the method of flat confrontation; the strain Ba-0321 was the strongest, with an antifungal effect of 75%. Moreover, this strain had broad spectrum antimicrobial activity to eight additional tobacco pathogens. The strain was identified as Bacillus velezensis by morphology and the 16S rDNA sequence. The B. velezensis strain Ba-0321 had strong UV resistance as well as tolerance to high temperatures and low nutrition. The bacteria inhibited spore germination and mycelial growth of F. oxysporum under in vitro co-culture conditions. In vivo assays demonstrated that the Ba-0321 strain significantly reduced the pathogenicity of F. oxysporum, resulting in a control effect on tobacco root rot of 81.00%. Simultaneously, the bacteria significantly promoted root development and the growth of tobacco plants.ConclusionOur results confirmed that the B. velezensis strain Ba-0321 has a strong antifungal effect and stress resistance that enable it to be used as a biological control agent for tobacco root rot caused by F. oxysporum.Significance and impact of the studyTobacco root rot caused by F. oxysporum has become a damaging disease in China. The B. velezensis strain Ba-0321 has promising application value for controlling tobacco root rot diseases, and it could provide a new biocontrol agent against root rot caused by F. oxysporum in other plant species.

In this paper, we collect 54 Gamma-Ray Burst (GRB) afterglows rebrightening in X-ray, optical, and radio bands to build the biggest sample so far, of which 18 type-Ic/b Supernova (SN)-associated GRBs have been deeply investigated. We confirm that the distribution of spectral luminosities of SN-associated GRBs has a wider scope of five orders of magnitude. After excluding short- and low-luminosity SN/GRBs, we obtain the mean light curves of high-luminosity SN/GRBs at different radio frequencies. It is found that the mean radio light curves peak twice on the tens of days and several months in each since the burst trigger. There is a time delay between radio afterglows at different frequencies, i.e. the high-frequency emissions come earlier than those low-frequency ones. We study in detail the multiband rebrightening behaviors of GRB 980425 and GRB 030329 with the most radio observation data at present. Unlike GRB 980425, the rebrightening component contributed from GRB 030329/SN 2003dh is indistinguishable. However, we predict that both SN/GRBs will produce the considerable mJy-level rebrightening emissions from their individual SN remnants on the late-times of 103th years for GRB 980425 and 64th years for GRB 030329, which is observable for the current facilities and would be detected by the forthcoming radio telescopes.

本文报告1例罕见的SMARCA4缺失胃癌。患者女，69岁，因腹胀伴恶心、呕吐入院。磁共振成像检查示胃窦部占位，胃镜活检示腺癌。镜下观察：肿瘤组织主要由大小不等的实性细胞巢构成，局部见形成不良的腺管状、筛状及失黏附性的条索状结构，局部胃黏膜内观察到印戒细胞癌的形态，肿瘤细胞未见横纹肌样形态。免疫组织化学染色示SMARCA4缺失。诊断为胃SMARCA4缺失的低分化腺癌。需要与神经内分泌癌和肝样腺癌鉴别。.

A lack of objective biomarkers is preventing the screening and diagnosis of COVID-19 combined with major depression disorder (COVID-19-MDD). The purpose of this study was to identify diagnostic biomarkers and gene regulatory mechanisms associated with autophagy; a crucial process significantly involved in the pathogenesis of COVID-19-MDD.In this study, differentially expressed genes (DEGs) were screened using GSE98793 from the GEO2R analysis (GEO) database, and intersected with the COVID-19-related gene (CRGs) and autophagy-related genes (ARGs) to obtain common genes involved in. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of these common genes were performed. Subsequently, the transcription factor (TF)-gene regulatory network and comorbidity network were constructed. In addition, 10 drug candidates were screened using the DSigDB database. To identify diagnostic markers, we used LASSO regression.In total, 13 common genes were screened, which were primarily enriched in lysosomes, endoplasmic reticulum membranes, and other endomembrane systems also associated with autophagy. Additionally, these genes were involved in neurological cell signaling and have a functional role in pathways related to vascular endothelial growth factor, tyrosine kinase, autophagy, inflammation, immunity, and carcinogenesis. Tumors and psychiatric disorders were the most highly linked diseases to COVID-19. Finally, ten drug candidates and eight diagnostic markers (STX17, NRG1, RRAGD, XPO1, HERC1, HSP90AB1, EPHB2, and S1PR3) were screened.This is the first study to screen eight diagnostic markers and construct a gene regulatory network for COVID-19-MDD from the perspective of autophagy. The findings of our study provide novel insights into the diagnosis and treatment of COVID-19-MDD.

A型胰岛素抵抗综合征是罕见的胰岛素受体基因突变引起的常染色体显性遗传病，表现为黑棘皮、严重胰岛素抵抗，但血甘油三酯正常，女性可表现为多囊卵巢综合征和高雄激素血症。本文报道1例青少年女性，以月经不规律、黑棘皮、严重胰岛素抵抗及血甘油三酯正常为特点，通过基因检测诊断为胰岛素受体杂合突变导致的A型胰岛素抵抗综合征，随访2年余，控制满意。提示严重胰岛素抵抗患者采用适宜的诊疗流程可帮助这些疑难患者得到确诊。.

患儿 男，11月龄，以频繁成簇抽搐发作起病，予地西泮、苯巴比妥及丙戊酸钠联合治疗无效，每天抽搐发作数十次，起病第4天因癫痫持续状态入住重症监护病房治疗，并出现嗜睡、意识模糊、不能认人、不自主动作、偶兴奋尖叫、夜间睡眠时间减少，脑电图背景活动慢化，监测到频繁后头部起源的临床发作及电发作，脑脊液抗AMPA2受体IgG抗体阳性，诊断抗AMPA2受体脑炎。予人免疫球蛋白及激素冲击免疫治疗，加用拉考沙胺并减停丙戊酸后抽搐缓解，意识转清。临床上以频繁局灶抽搐发作伴有意识水平下降为主要表现的婴儿，应注意鉴别抗AMPA2受体脑炎，尽早启用免疫治疗改善预后至关重要。.

The article "METTL3 promotes the progression of nasopharyngeal carcinoma through mediating M6A modification of EZH2, by Q.-Z. Meng, C.-H. Cong, X.-J. Li, F. Zhu, X. Zhao, F.-W. Chen, published in Eur Rev Med Pharmacol Sci 2020; 24 (8): 4328-4336-DOI: 10.26355/eurrev_202004_21014-PMID: 32373970" has been retracted by the authors. After publication, several issues were raised on PubPeer about the reliability of the published results. The same authors stated that the study was not performed in accordance with the standard procedures required. In particular, Figure 1 also presents some concerns as it does not reflect the experimental data reported in the study. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/21014.

Bletilla striata is an important Chinese herbal plant grown widely in southwest China (Qian et al. 2021). Leaf blight was found on cultivated bletilla crops in Yunnan in 2021. The disease infected bletilla leaves and it was present in the field from April to November with the highest incidence (86% plants diseased) recorded in early September in Puer area. Foliar lesions were circular (Φ0.5-1.8 cm) or oval, with pale-gray center and narrow gray-brown outer area surrounded by a yellow halo. The lesions coalesced later to form large irregular spots or blighted areas on leaves. Symptomatic bletilla leaves were sampled from fields in Jiangcheng (E101.8672o, N22.5803o) and Simao (E109.7816o, N22.7891o) counties, Yunnan in July 2021. Seven fungal isolates were obtained from (BJ01-BJ04) and Simao samples (HBJ05-HBJ07) via lesion-tissue culture and hypha-tip purification on PDA medium. A pathogenicity test following Koch's Postulates (Grimms et al. 2006) was conducted using each isolate by inoculating 45-day old bletilla plant (n=30, Zihua cultivar) in a greenhouse through spraying hypha-spore suspension (3.25×104 CFU/mL) prepared with 14 d fresh DNA culture. Non-inoculated plants (n=30) were used as controls. The experiment was repeated once. The isolates BJ02 and HBJ06 (deposited in Yunnan Agric. Univ. Microbes Herbarium) were shown pathogenic to bletilla since similar lesions formed on seedlings 7 d post inoculation and pure fungal cultures with the same colony morphology as those of BJ02 and HBJ06 were re-isolated from leaf lesions 14 dpi. Isolates BJ02 and HBJ06 produced identical colony and conidium morphology after they were incubated at 25oC for 7 d on PDA. Colonies were circular, pale brown, Φ5.5-7.5cm, with villous surface and abundant aerial hyphae. Mycelia were septate, colorless, Φ3-4 µm and with acute-angled branches. Conidiophores developed from hyphae were erect, septate, pale-brown colored and 60-200 µm long. Conidia (produced scarcely and ripened slowly) were long-oval or petaloid, straight or slightly curved, brown, sized 28-45×10-14 µm. Most conidia were divided into 4 cells by 3 septa; the middle two were bigger than the basal and apex cells. Both BJ02 and HBJ06 were identified as Curvularia sp. based on their morphological characters (Tan et al. 2018). The rDNA-ITS, TEF1α and GAPDH genes (Tan et al. 2018) were amplified from these isolates with PCR (White et al. 1990) and sequenced. ITS sequences of the two isolates were both 574 bp (acc. no. OL587997OL336480) and 100% (574/574 bp) identical shown by blast comparison. Further blast analyses of ITS (574 bp, OL587997), TEF1α (532 bp, ON637120) and GAPDH (881 bp, ON637121) from isolate BJ02 showed that they were 99.27% (547/551 bp), 100% (842/842 bp) and 99.8% (507/508 bp) identical respectively with those of Curvularia reesii BRIP4358 (MH414907). The 3 genes of BJ02 were concatenated and phylogenic analysis (Tamura et al, 2013) of the concatenated sequence with those of Curvularia spp. showed that BJ02 was clustered with C. reesii BRIP4358 on the same end-branch of the tree with 100% confidence. Therefore, BJ02 and HBJ06 are the same species identified as Curvularia reesii and it is the pathogen causing bletilla leaf blight. C. reesii was first isolated from the air in Australia in 1963 and was named by Tan et al. in 2018. It has not been reported as a plant pathogen elsewhere. This is the first record of this fungus causing bletilla leaf blight in China. Keywords: Bletilla striata; leaf blight; Curvularia reesii; disease symptoms; pathogen morphology; multigene identification References (1) D.J. Grimes. Microbes, 1(5): 223-228, 2006. (2) L.H. Qian et al. Jiangshu Agric. Sci. 49(19): 64-71, 2021. (3) K. Tamura et al. Mol. Bio.Evol. 30 (12): 2725- 2729, 2013. (4) Y. P. Tan et al. MycoKeys, 35: 1-25. 2018. (5) T.J. White et al. In: PCR Protocols: A Guide to Methods and Applications (eds. M.A. Innis et al.), Acad. Press, Inc. New York. 315-322, 1990.

We systematically analyze three GRB samples named as radio-loud, radio-quiet and radio-none afterglows, respectively. It is shown that dichotomy of the radio-loud afterglows is not necessary. Interestingly, we find that the intrinsic durations ($T_{int}$), isotropic energies of prompt gamma-rays ($E_{\gamma, iso}$) and redshifts ($z$) of their host galaxies are log-normally distributed for both the radio-loud and radio-quiet samples except those GRBs without any radio detections. Based on the distinct distributions of $T_{int}$, $E_{\gamma, iso}$, the circum-burst medium density ($n$) and the isotropic equivalent energy of radio afterglows ($L_{\nu,p}$), we confirm that the GRB radio afterglows are really better to be divided into the dim and the bright types. However, it is noticeable that the distributions of flux densities ($F_{host}$) from host galaxies of both classes of radio afterglows are intrinsically quite similar. Meanwhile, we point out that the radio-none sample is also obviously different from the above two samples with radio afterglows observed, according to the cumulative frequency distributions of the $T_{int}$ and the $E_{\gamma, iso}$, together with correlations between $T_{int}$ and $z$. In addition, a positive correlation between $E_{\gamma, iso}$ and $L_{\nu,p}$ is found in the radio-loud samples especially for the supernova-associated GRBs. Besides, we also find this positive correlation in the radio-quiet sample. A negative correlation between $T_{int}$ and $z$ is confirmed to hold for the radio-quiet sample too. The dividing line between short and long GRBs in the rest frame is at $T_{int}\simeq$1 s. Consequently, we propose that the radio-loud, the radio-quiet and the radio-none GRBs could be originated from different progenitors., Comment: 20 pages, 30 figures, submitted to MNRAS

The rotor-stator interaction between the impeller and the volute is the main reason for the pump pressure pulsation and vibration. This work aims at designing a new type of tongue to minimize pressure pulsation, reduce vibration noise and energy loss. Inspired by the humpback pectoral fin, four volute tongues are investigated in this paper, three of which are sinusoidal tubercle volute tongues (STVT) and one is the original volute tongue (OVT). Based on the detached-eddy simulation (DES) turbulence model, the influence of the sinusoidal tubercle volute tongues on the pressure pulsation was investigated, and the flow structure and enstrophy of the four pumps were analyzed, aiming to minimize pressure pulsation, maximize hydraulic performance and reduce the energy dissipation in centrifugal pumps. The results show that the pressure pulsations of the STVT profiles are all lower. The reductions of the average pressure pulsation at the monitoring points are 13.3% (STVT-1), 20.6% (STVT-2), and 16.2% (STVT-3), respectively. The difference in pressure pulsation at the monitoring points closer to the tongue is more obvious. At the design flow rate, the efficiencies of the three bionic pumps are increased by 0.5% (STVT-1), 1.5% (STVT-2), 0.9% (STVT-3), respectively. The STVT profiles change the vortex structure near the tongue and minimized the vortex strength. Meanwhile, the flow in the pump with the STVT profiles have lower enstrophy. The enstrophy of the flow with the STVT-2 profile is the lowest, which is reduced by about 8%. This reduces the dissipation of mechanical energy. The results can be used as a guide for pump design optimization.

A compact ultra-wideband (UWB) and triband patch antenna with the partial ground plane is presented in this paper. Initially, the antenna is designed for UWB applications, operating at the UWB portion of the spectrum ranging from 3.1 GHz to 10.6 GHz, then it is modified to operate at three distinct frequencies of 2.45 GHz, 5 GHz, and 10.2 GHz. The proposed antenna is inspired by a classic rectangular patch antenna in which slots, stubs, and defected ground structure (DGS) were introduced to increase its operational bandwidth. Good results in terms of return loss are found in all resonant frequencies as well as for the single wideband. In addition, the proposed antenna has been compared with related works in the literature, to highlight its potential for future UWB and multiband portable devices.

DNA methylation was one of the earliest discovered epigenetic modifications in vertebrates, and is an important epigenetic mechanism involved in the expression of genes in many biological processes, including muscle growth and development. Its effects on economically important traits are evidenced in reported differences in meat quality traits between Chinese indigenous pig breeds (Wannanhua pig) and Western commercial pig breeds (Yorkshire pig), and this presents a unique model for analyzing the effects of DNA methylation on these traits. In the present study, a whole genome DNA methylation analysis was performed on the two breeds using methylated DNA immunoprecipitation. GO functional enrichment and pathway enrichment analyses identified differentially methylated genes primarily associated with fatty acid metabolism, biological processes of muscle development and signaling pathways related to muscle development and pork quality. Differentially methylated genes were verified by sodium pyrosequencing, and the results were consistent with the sequencing results. The results of the integrative analysis between DNA methylation and gene expression revealed that the DNA methylation levels showed a significantly negative correlation with gene expression levels around the transcription start site of genes. In total, 41 genes were both differentially expressed and methylated; these genes were related to fat metabolism, lipid metabolism and skeletal muscle development. This study could help further explore the molecular mechanisms and phenotypic differences in pig growth and development among different breeds.

We study here the underlying factors that govern the stability of austenite in a medium Mn (Fe–0.18C–11Mn–3.8Al) (wt-%) steel. In this regard, a novel heat treatment involving intercritical quenchi...

Daytime sleepiness has some association with cardiometabolic diseases and osteoporosis, but it is unknown whether their relationship is causal. This two-sample Mendelian randomization (MR) study aims to explore their causal relationship.We included the largest genome-wide association studies (GWASs) associated with daytime sleepiness, cardiometabolic diseases and osteoporosis. 34 single nucleotide polymorphisms (SNPs) were used as the instrumental variables of daytime sleepiness.Genetic predisposition to excessive daytime sleepiness was strongly associated with increased risk of coronary artery disease (beta-estimate: 0.610, 95% confidence interval [CI]: 0.128 to 1.093, standard error [SE]: 0.246, p-value=0.013) and may increase the incidence of type 2 diabetes (beta-estimate: 0.614, 95% CI: 0.009 to 1.219, SE: 0.309, p-value=0.047). We found no causal influence of daytime sleepiness on heart failure, atrial fibrillation, cerebral ischemia, intracerebral hemorrhage, forearm bone mineral density (FA-BMD), femoral neck BMD (FN-BMD), and lumbar spine BMD (LS-BMD).This study suggested that excessive daytime sleepiness was causally associated with increased risk of coronary artery disease, which may benefit to prevent this disease.

OBJECTIVE: To explore the relationship between tumor necrosis factor like weak inducer of apoptosis (TWEAK) gene and the pathogenesis of rheumatoid arthritis (RA) by detecting the DNA methylation level, mRNA expression level and serum protein concentration of TWEAK gene in peripheral blood. METHODS: The MassARRAY method was used to detect the DNA methylation level of the TWEAK gene in the peripheral blood of 112 RA patients and 86 matched healthy volunteers. The real-time quantitative polymerase chain reaction method was used to detect the mRNA expression level of the TWEAK gene in the peripheral blood of the subjects. The enzyme-linked immunosorbent assay method was used to detect the serum TWEAK protein concentration of the subjects. The TWEAK gene DNA methylation level, mRNA expression level and serum protein concentration between the RA group and the healthy control group were compared, and the relationship between it and the degree of disease activity analyzed. RESULTS: The overall DNA methylation level of TWEAK gene and the DNA methylation levels of CpG_11, CpG_17.18.19.20, CpG_40.41.42 site in the RA group were higher than those in the healthy control group (P=0.002, P=0.01, P=0.006, P=0.002, respectively). The DNA methylation level of CpG_55.56 site in the high disease activity group was higher than that in the medium and low disease activity group (P=0.041). The expression level of TWEAK gene mRNA in the peripheral blood of the RA group was lower than that of the healthy control group (P=0.023). The expression level of TWEAK gene mRNA in the high disease activity group was lower than that in the medium and low disease activity group (P=0.035). The serum TWEAK protein concentration of the RA group was not significantly different from that of the healthy control group (P=0.508), but it was positively correlated with the mRNA expression level (r=0.482, P < 0.001). CONCLUSION: The TWEAK gene is closely related to the onset and progression of RA, and its hypermethylation state may be one of the epigenetic mechanisms regulating its low mRNA expression, and it can be used as one of the important indicators for clinical monitoring and evaluation of RA.

The early identification and prediction of hand-foot-and-mouth disease (HFMD) play an important role in the disease prevention and control. However, suitable models are different in regions due to the differences in geography, social economy factors. We collected data associated with daily reported HFMD cases and weather factors of Zibo city in 2010~2019 and used the generalised additive model (GAM) to evaluate the effects of weather factors on HFMD cases. Then, GAM, support vectors regression (SVR) and random forest regression (RFR) models are used to compare predictive results. The annual average incidence was 129.72/100 000 from 2010 to 2019. Its distribution showed a unimodal trend, with incidence increasing from March, peaking from May to September. Our study revealed the nonlinear relationship between temperature, rainfall and relative humidity and HFMD cases and based on the predictive result, the performances of three models constructed ranked in descending order are: SVR > GAM> RFR, and SVR has the smallest prediction errors. These findings provide quantitative evidence for the prediction of HFMD for special high-risk regions and can help public health agencies implement prevention and control measures in advance.

Partially-depleted silicon-on-insulator (PDSOI) MOSFETs with full dielectric isolation structure are widely used in the high temperature field of 225 °C, but affected by the threshold voltage and carrier mobility, the saturated output current has a rate of change as high as 24.9% at 25 °C–300 °C, which will reduce the working speed and accuracy of the analog circuit. This paper studies the high temperature output current characteristics of ultra-thin body and buried oxide (UTBB) fully-depleted silicon-on-insulator (FDSOI) MOSFETs with the 28 nm low voltage threshold structure. The experimental results show that when the gate voltage of the device is constant, the saturation current change of 28 nm short-channel FDSOI device is 1.93% in the temperature range from 25 °C to 300 °C, which is 12.9 times more stable than that of 0.13 μm PDSOI device, 4.5 times and 8.4 times higher than that of 0.3 μm and 2 μm long-channel FDSOI device. When the gate voltage of the device drifts from the zero-temperature coefficient (ZTC) point by ±10%–±20%, the output current change of the short-channel FDSOI device is still the lowest. It is proved by theory and simulation that the low temperature change rate of the carrier velocity of the short-channel FDSOI device is the main factor affecting the stability of the output current. From the analysis of the saturation current model and the ZTC operating point, reducing the gate operating voltage of the device or increasing the threshold voltage of the device can further improve the stability of the output current at high temperatures. The research in this paper proves that the 28 nm UTBB FDSOI device has good high temperature saturation current stability, which can well meet the output current stability requirements of high temperature analog circuits.

Hydraulic fracturing is an effective measure to increase production and injection and blockage removal in oil and gas field development. Accurate prediction of fracture morphologies is the key to the optimized design of hydraulic fracturing. The cohesive zone model (CZM) has been widely used in the numerical simulation of fracture initiation and propagation during hydraulic fracturing. The fractures formed by the numerical simulation vary significantly with different CZMs. In the current numerical simulation, the CZM generally adopts the bilinear model, which is more suitable for describing brittle fracture, while rocks are quasi-brittle materials and have nonlinear CZMs. This deviation should be corrected. Moreover, the CZM parameters are generally determined based on experience, without a reliable basis and standard determination method. This article focused on the CZM, systematically introduced its concept and classification, and clarified the correlation between the types of CZMs and the brittleness, quasi-brittleness, and ductility of rock fracture. The application of CZM in hydraulic fracturing was reviewed, and the existing problems, corresponding countermeasures and future research trends were presented. An integrated method of combining laboratory experiments, data mining and numerical simulation to determine the CZMs of mode I, mode II, and I/II mixed mode cohesive cracks was proposed.

Horizontal well multistage fracturing in the roof of broken soft coal seams has been demonstrated to be an effective technique to extract coalbed methane (CBM). However, fracture propagation behaviours under this technology vary significantly with different roof lithologies. Therefore, the influence of roof lithology on fracture propagation was investigated in this study. Based on the No. 5 and No. 11 coal seams in the Hancheng block of the Ordos Basin in China, field tests of horizontal well multistage fracturing in the sandstone and mudstone roof of crushed soft coal seams were performed and fractures were detected by microseismic monitoring. Corresponding hydraulic fracturing physical simulation experiments were conducted. The results show that the effectively propped fractures in the roof can provide flow channels for CBM. The better microseismic monitoring fractures and higher CBM production than direct fracturing in coal seams demonstrated the desirable feasibility of this technology. For the sandstone roof, the morphologies of hydraulic fractures were regular and one main fracture was formed by each perforation cluster. For the mudstone roof, the shapes of fractures were irregular and complicated fracture networks were formed. The findings can improve the design of horizontal well multistage fracturing in the roof of broken soft coal seams.

GGG70L is a kind of cold-working die steel widely used in large automobile cover parts die. In order to ensure the life of the die, laser quenching process is usually used to form a certain hardened layer at a specific part of the die. In this paper, the changes of microstructure and hardness of ductile iron GGG70L after laser quenching were studied through a large number of process experiments, and the influence of quenching process parameters on the microstructure and properties of GGG70L was obtained. The relationship between the depth of hardened layer and the laser energy density is established and a quadratic function relationship was found between the two. It is found that both higher hardness and deeper hardening depth can be obtained when the energy density is 24-28 (J/mm2). The finite element model of the laser quenching process of GGG70L was established, and the temperature of the hardened zone and its evolution law during the laser quenching process were studied numerically.

Friction stir processing (FSP) is a method to produce severe plastic deformation (SPD) of materials, which can well improve and optimize the microstructure and mechanical properties of Mg-Li alloy. In this paper, the FSP experiment of LA103Z Mg-Li alloy was conducted, and the influence of process parameters on the microstructure, tensile strength, elongation after fracture and fracture morphology of the material was studied. The microstructure of the Mg-Li alloy after FSP was significantly refined. With the increasing rotational speed of the stirring head, the grain boundaries became clearer and more distinguishable, and the low angle grain boundaries transformed into the high angle grain boundaries. With the increasing feed speed of the stirring head, the grain refinement became more pronounced, and the dispersion of α-Mg phase in the stir zone became more uniform and distributed at the grain boundaries. When the rotational speed and the feed speed of the stirring head were 800-1000 r/min and 100-200 mm/min respectively, the comprehensive performance of the Mg-Li alloy plate after FSP was expected to be optimal.

OBJECTIVE: To analyze the changes and characteristics of pediatric outpatient visits in a general hospital before and after the coronavirus disease (COVID-19) epidemic. METHODS: Based on the registration data of pediatric outpatient visits in the information system (HIS)of Beijing Tsinghua Changgung Hospital, from January 1 2018 to December 31 2020, aged 0 to 16 years, we analyzed the changes of outpatient visits before and after the epidemic, focusing on respiratory infection including influenza. The relationship between the outpatient visits and age and quarterly distribution were also studied. RESULTS: (1) Respiratory infection accounted for the majority of outpatient visits in 2018 and 2019 (60.6% and 60.5%, respectively). Non-respiratory infection accounted for the main proportion of outpatient visits in 2020, while respiratory infection accounted for only 47.4%. Annual respiratory infection visits, respiratory infectious diseases visits especially influenza visits all decreased significantly in 2020 compared with that in 2018 and 2019 (P < 0.05). (2)Respiratory infection visits were highest in the infant group, lowest in the school age group (P < 0.05) and highest in the fourth quarter each year. It decreased significantly in the second quarter of 2020 with statistical significance when compared with the other quarters of 2020(P < 0.05). (3)Influenza accounted for the highest proportion of respiratory infectious diseases visits in each year. It was highest in first quarter, which was significantly different from the other quarters of the year (P < 0.05). There were different distributions of influenza visits throughout 2018 and 2019, while it was only distributed in the first quarter and 99% in January in 2020. CONCLUSION: The respiratory infection and influenza visits have decreased significantly in our pediatric outpatient department after the COVID-19 epidemic, which is considered closely related to the lifestyle and personal protection after the epidemic. It is recommended that health education on respiratory infection and influenza prevention should be strengthened, especially in winter and spring, to promote the development of good respiratory and hand hygiene habits.

We collect 133 Fast Radio Bursts (FRBs), including 110 non-repeating and 23 repeating ones, and systematically investigate their observational properties. To check the frequency dependence of FRB classifications, we define our samples with a central frequency below/above 1GHz as subsample I/II. We find that there is a clear bimodal distribution of pulse width for the subsample I. And If we classify FRBs into short FRBs (\emph{s}FRBs) ($$100 ms) as done for short and long Gamma-Ray Bursts (GRBs), the \emph{s}FRBs at higher central frequency are commonly shorter than those at lower central frequency not only for non-repeating but also repeating \emph{s}FRBs. Secondly, we find that fluence and peak flux density are correlated with a power law relation of $F \varpropto S{^{\gamma}_{p,obs}}$ for both \emph{s}FRBs and \emph{l}FRBs whose distributions are obviously different. Thirdly, the \emph{l}FRBs with isotropic energies ranging from $10^{42}$ to $10^{44}$ erg are more energetic than the \emph{s}FRBs in the $F- DM_{EX}$ plane, indicating that they are two representative types. Finally, it is interestingly note that the peak flux density behaves an independence on the redshift when the distance of the FRBs becomes far enough, which is similar to the scenario of peak flux evolving with redshift in the field of GRBs. We predict that fainter FRBs at higher redshift of $z>2$ can be successfully detected by FAST and SKA in the near future., Comment: 10 pages,4 figures,2 tables,accepted for publication in ApJ

In the double cold rolling process, oil film thickness in the deformation zone is a key parameter for evaluating rolling lubricity. This study investigated the formation and variation mechanism of ...

The gut microbiota of chickens plays an important role in host physiology. However, the colonization and prevalence of gut microbiota have not been well-characterized. Here, we performed 16S rRNA gene sequencing on the duodenal, cecal and fecal microbiota of broilers at 1, 7, 21, and 35 days of age and characterized the dynamic succession of microbiota across the intestinal tract. Our results showed that Firmicutes was the most abundant phylum detected in each gut site at various ages, while the microbial diversity and composition varied among the duodenum, cecum, and feces at different ages. The microbial diversity and complexity of the cecal microbiota increased with age, gradually achieving stability at 21 days of age. As a specific genus in the cecum, Clostridium_sensu_stricto_1 accounted for 83.50% of the total abundance at 1 day of age, but its relative abundance diminished with age. Regarding the feces, the highest alpha diversity was observed at 1 day of age, significantly separated from the alpha diversity of other ages. In addition, no significant differences were observed in the alpha diversity of duodenal samples among 7, 21, and 35 days of age. The predominant bacterium, Lactobacillus, was relatively low (0.68–6.04%) in the intestinal tract of 1-day-old chicks, whereas its abundance increased substantially at 7 days of age and was higher in the duodenum and feces. Escherichia-Shigella, another predominant bacterium in the chicken intestinal tract, was also found to be highly abundant in fecal samples, and the age-associated dynamic trend coincided with that of Lactobacillus. In addition, several genera, including Blautia, Ruminiclostridium_5, Ruminococcaceae_UCG-014, and [Ruminococcus]_torques_group, which are related to the production of short-chain fatty acids, were identified as biomarker bacteria of the cecum after 21 days of age. These findings shed direct light on the temporal and spatial dynamics of intestinal microbiota and provide new opportunities for the improvement of poultry health and production.

Elongation factor Tu GTP-binding domain containing 2 (EFTUD2) is an essential constituent of U5 small nuclear ribonucleoproteins (snRNPs) and plays a crucial role in spliceosome activation and cancer. The mechanism of EFTUD2 on carcinogenesis and development of liver cancer still need further study. Bioinformatic analysis was performed to find differential expressed genes and related pathways. Western blotting and quantitative PCR assays were used to verify the EFTUD2 expression in HCC cell lines and tumor tissues of liver cancer patients. Transfection of shRNAs in SKHEP1 and Huh7 cell lines was conducted to explore the mechanisms of EFTUD2 in HCC. CCK-8 method, colony formation, and cell cycle detection kit were used to detect the proliferation. A tumor model in nude mice was used to explore the role of EFTUD2 in liver cancer in vivo. Based on the tumor tissues and para-tumor tissues in our HCC patients, we identified EFTUD2 as highly expressed in HCC tissues (P