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Synthetic Aperture Radar (SAR) has the advantage of noncontact monitoring around the clock and is an important tool for closed space security monitoring. However, when SAR is employed in complex closed spaces, it is susceptible to multipath effects, resulting in a considerable number of virtual images in the image, which has a detrimental impact on interpretation. Existing methods require scene priors for multipath estimation or subaperture weighted fusion to suppress multipath; however, accurately distinguishing multipath virtual images from target images is challenging. This paper proposes a novel multi-angle dual-layer deviation measurement method that effectively distinguishes multipath virtual images from targets. The proposed method employs a large viewing angle difference to conduct multi-angle observation of the target scene, capitalizing on the fact that the position of the multipath virtual image varies with the observation angle, whereas the actual target position remains constant; this is followed by applying a dual-layer deviation measurement algorithm. The algorithm calculates the deviation between the sequence amplitude value and mean twice based on the sparsity of multipath in the multiangle sequence. The proposed method accurately detects and removes sparse and unstable multipath components, whereas the remaining stable components are averaged. This effectively suppresses multipath while retaining target information. Finally, the simulation and actual millimeter wave radar data processing verified the effectiveness of the proposed method.

Atmospheric influence is the main interference factor in Ground-Based Interferometric Synthetic Aperture Radar (GB-InSAR) deformation monitoring. Due to the complex terrain and various environmental factors, the correction method based on the assumption of a uniform atmospheric influence may lead to low atmospheric correction accuracy. In this paper, a two-stage semi-empirical model is proposed to correct the atmospheric phase screen during the GB-InSAR monitoring of a super large slope under complex atmospheric conditions. First, the observed atmospheric phase is modeled according to the height and range of the terrain structure to correct the linear atmospheric phase. Then, considering the complex atmospheric conditions and the spatially nonuniform atmosphere with a large azimuth field of view, stable Persistent Scatterers (PS) are selected to obtain the atmospheric phase of all PS by interpolation to correct the nonlinear atmospheric phase. This method is used to process a large field of view radar image of the foundation of the Xinpu and Outang landslides in the Three Gorges Reservoir area. Compared with the conventional method, the atmospheric phase error is reduced by approximately 2 mm. This method effectively corrects the nonuniform atmospheric phase under the landslide monitoring scene and meets the wide-area monitoring needs of the landslide.

In order to investigate the role of intestinal bacteria in the absorption of Lycium barbarum polysaccharides (LBP), a strain of bacteria was isolated from human intestinal feces, and the strain was applied in the fermentation of LBP. The total number of bacteria, pH, polysaccharide content, reducing sugar content and molecular weight in the fermentation were measured and analysed to initially elucidate the digestion and absorption of LBP. The results showed that the strain was Enterobacter hormaechei through morphological and molecular biology identification, marked 4-2-1, which was a Gram-negative bacterium, and that it reached its maximum total bacterial count at 12 h. After fermentation, the pH of the medium changed from 7.98 to 7.75, the polysaccharide content changed from 682 μg/mL to 205.7 μg/mL, the reducing sugar content changed from 225 μg/mL to 91.32 μg/mL, and the molecular weight changed from 8.02 to 3.44 kDa, the content of LBP decreased to about 30.2%, the content of reducing sugar decreased to about 40.6% and the molecular weight decreased to 42.9%. It indicated that the intestinal bacteria could ferment and utilize LBP, which would provide a basis for further study on the interaction between LBP and intestinal bacteria.

SAR three-Dimensional (3D) imaging of complex structural facilities is an important and challenging issue in SAR imaging. The existing 3D SAR imaging relies on multiple channels or flights in the elevation direction, exerting high demands on the radar system or data acquisition. This paper proposes a 3D imaging method for complex structural facilities without a prior model, and the full-aspect 3D image of the entire scene in the region with unknown prior information can be obtained solely using a single flight. This method completely utilizes the full-aspect observation as well as the layover and elevation ambiguity resolving capabilities of circular SAR without requiring target pre-modeling and 3D imaging grid construction. Moreover, the method is suitable for fine 3D imaging complex structural facilities in large areas. Significant progress has been made in the practical technology of radar 3D imaging. The full-aspect 3D radar images of the FAST radio telescope are obtained for the first time with the proposed method, thus verifying the correctness and effectiveness of our theory and method.

Using purple yam powder, quinoa powder and low-gluten powder as raw materials, the maximum shear force and sensory scores were used as indicators to investigate the effects of purple yam powder, quinoa powder, xylitol, oil, and milk powder on purple yam quinoa sugar-free biscuits. For the influence of quality, orthogonal experiment was carried out on the basis of single factor experiment to optimize the biscuit craft formula, and research was conducted on microorganisms, physicochemical, nutritional indicators and in vitro digestion characteristics. The results showed that the best formula for purple yam quinoa sugar-free biscuits: Based on 100% mixed powder (low-gluten, purple yam powder and quinoa powder), pastry powder 80%, purple yam powder 13%, quinoa powder 7%, xylitol 30%, fat 30%, milk powder 5%, egg 4%, baking soda 0.8%, monoglyceride 0.8%, salt 0.15%, citric acid 0.3%. The biscuits made under this process had a sensory score of 93.6 and a maximum shear force of 4.13 N. At the same time, the physical, chemical and health indicators meet the corresponding national standards for biscuits. Biscuit hydrolysis index and estimated glycemic index (EGI) were 55.12 and 69.97, respectively, which indicated the biscuits were medium glycemic index foods.

Background and objective The absence of α-gal in humans is caused by the inactivity of α-1,3GT gene. However, humans have pre-existing and abundant anti-gal antibodies. Xenotransplantation procedures have indicated the high potential of introducing α-1,3GT gene to synthesize α-gal for cancer gene therapy by mimicking hyper-acute rejection. The aim of this study is to construct a lung cancer A549 cell line that expressed α-gal, and to observe the antitumor mechanisms mediated by human serum. Methods A549 cells were transfected with pEGFP-N1-GT plasmids constructed in a previous study. A stable transgenic cell line, A549-GT, was then selected and cultivated. The biological characteristics of A549-GT cells, including morphology and proliferation, were examined. α-1,3GT mRNA expression was detected by RT-PCR. Direct immunofluorescence staining and flow cytometry (FCM) were used to analyze the synthesis of α-gal in A549-GT. The binding of human serum IgM and C3 with A549-GT were also detected. Results α-1,3GT mRNA was expressed in A549-GT. Direct immunofluorescence staining and FCM indicated a high and stable α-gal expression rate in A549-GT. Compared with parental A549 cells, the biological characteristics of A549-GT were unaltered. α-Gal expression was not detected in the human fetal lung fibroblast cell line MRC-5 even though A549-GT and its culture medium were cultivated with the enzyme. Immunofluorescence staining and FCM also indicated abundant binding between A549-GT treated with human serum and IgM/C3. Conclusion α-Gal expression in tumor cells by gene transduction can induce complement-dependent cytototic antitumor effects.

Background and objective It has been confirmed that nm23-H1 gene is one of the tumor metastasis suppressor genes. Up to now, the exact mechanism of nm23-H1 gebe is uncertain. The aim of this study the mechanism of metastasis suppressor gene nm23-H1 involving in the Ras signaling of lung cancer. Methods The wild and mutant typeof pEGFP-nm23-H1 plasmids [WT (wild type), H118F, S120G, P96S, S44A] were transfected into the L9981 lung cancer cell lines through liposome method, and the complex of KSR and nm23-H1 was detected through co-immunoprecipitation and Western blot assay. Results The human KSR could be detected in the nm23-H1 immunoprecipitations in all the trasfected L9981 lung cancer cell lines. But no significant difference of KSR expression was found in the wild and mutantnm23-H1 trasfected cell lines (F =0.190, P =0.938). Conclusion There was a close interaction between nm23-H1 and KSR, which was independent of the nm23-H1 mutation. Nm23-H1 involving in the Ras signaling of lung cancer may be through the KSR gene.

In order to comprehensively and objectively evaluate and analyze the quality of table Chinese olive (Cauarium album L.) fruits from different varieties (lines), a rapid method for the detection of the quality characteristics of table Chinese olive was established. In this study, the fruit quality of 10 different varieties (lines) of Chinese olive was evaluated by fuzzy mathematics sensory evaluation and multi-frequency pulsed electronic tongue and its correlation with physicochemical indicators was analyzed. On this basis, a quality prediction model of table Chinese olive was developed and evaluated in terms of coefficient of determination (R2) and average relative error (δ). Sensory evaluation on a nine-point hedonic scale using the Delphi method showed that the total weight of sweetness and astringency were 76.9%, both of which were the major quality characteristics of table Chinese olive fruit. The correlation analysis indicated that phenol-to-sugar ratio was significantly correlated with aftertaste sweetness and astringency (P < 0.01). According to principal component analysis (PCA), the best electrode combination for multi-frequency pulse electronic tongue to distinguish the fruit quality of different varieties of Chinese olive was palladium (10 Hz) and titanium (10 Hz). Multiple stepwise regression was used to develop a model describing the relationship between sensory evaluation score or physicochemical indicators and electronic tongue signal eigenvalues. It was found that the physicochemical indicators could be effectively predicted from the electronic tongue signal eigenvalues and the prediction performance for phenol-to-sugar ratio (R2 = 0.832, δ = 10.89%) and soluble sugar content (R2 = 0.831, δ = 5.75%) was best, followed by total phenol content (R2 = 0.783, δ = 12.08%). The sensory evaluation score could be effectively predicted by the regression model based on phenol-to-sugar ratio or electronic tongue signal eigenvalues, and the predictive effect of the model based on phenol-to-sugar ratio was better than that of the one based on tongue signal eigenvalues. However, the R2 values of the two models were low, only 0.589 and 0.542, respectively. These results provide a reference for the rapid detection of Chinese olive quality characteristics and the selection of excellent varieties.

BackgroundThe narratives of hierarchical medical sytem are generally classified into two patterns, one is the policy narrative, which is used to persuade the target audience to gain their support in practice, and the other is the academic narrative, which describes the thinking process of researchers to explore problems and enhance perceptions using words. The narratives of the hierarchical medical system are rich and diverse, but have been rarely systematically reviewed and summarized.ObjectiveWe explored the evolution process, focuses and characteristics of academic narratives of 10-year development of hierarchical medical system in China using social network analysis, aiming to provide a reference for improving the implementation of hierarchical medical system.MethodsOn March 21, 2021, we searched the database of CNKI for studies regarding hierarchical medical system in China published in academic journals in Chinese during January 1, 2009 to March 21, 2021 using "hierarchical medical system" "seeking healthcare in an orderly way" "seeking diagnosis and treatment services in an orderly way" "division of healthcare" "division of diagnosis and treatment" "first contact in primary care" "treating acute and chronic diseases separately" "cooperation between tertiary and secondary/primary hospitals" "bi-directional referrals" as keywords. Bibliometric methods, SATI 3.0 and UCINET 6.0 were used to explore the process, focuses and characteristics of academic narratives of hierarchical medical system through time series analysis, high-frequency keywords analysis, centrality analysis and small group analysis, and to generate visualized co-occurrence network diagrams of high-frequency keywords.ResultsA total of 4 882 studies were included for analysis. According to the results of time series analysis, the development of the hierarchical medical system could be roughly divided into three stages: embryonic stage (2009—2013) , acceleration stage (2014—2017) and standardization stage (2018 to present) . In terms of the use of frequency, the top five high-frequency keywords were "hierarchical medical system" "medical consortium" "primary healthcare institutions" "bi-directional referrals" and "public hospitals". In terms of closeness centrality, the top five high-frequency keywords were "hierarchical medical system" "medical consortium" "primary healthcare institutions" "bi-directional referrals" and "general practitioners". Small-group analysis yielded three groups of word clusters: core word clusters (including "medical consortium" "reform of public hospitals" "bi-directional referrals" "general practitioners" and "first contact in primary care") , secondary word clusters (including "the internet" "internet-based healthcare" "internet-based hospital" and "telemedicine") , and marginal word clusters (including "diabetes" "chronic disease" "cognition" and "influencing factors") . Health policy rhetoric was an important part of the core word clusters. And secondary and marginal word clusters were constantly evolving and generating.ConclusionThe academic narratives of hierarchical medical system have gradually derived from the mutually-promoted development of policies and real implementation regarding the hierarchical medical system, generally demonstrated various structures and relatively homogeneous research direction. Available academic and policy narratives of the hierarchical medical system are still limited to the scope of guiding principles, and the implementation of the concept and system still relies on the top-down push from the policy-making level, while the self-motivated micro-practices of hierarchical medical system in primary care have not yet emerged.