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Floods are among the most serious natural disasters worldwide; they cause enormous crop losses every year and threaten world food security. Many studies have focused on flood impact assessments for administrative districts, but fewer have focused on postdisaster impact assessments for specific crops. Therefore, this study used remote sensing data, including the normalized difference vegetation index (NDVI), elevation data, slope data, and precipitation data, combined with crop growth period data to construct a crop flood damage assessment index (CFAI). First, the analytic hierarchy process (AHP) was used to assign weights to the impact parameters; then, the Weighted Composite Score Method was used to calculate the CFAI; and finally, the impact was classified as sub-slight, slight, moderate, sub-severe, or severe based on the magnitude of the CFAI. This method was used for the Missouri River floods of 2019 in the United States and the Henan flood of 2021 in China. Due to the lack of measured data, the disaster vegetation damage index (DVDI) was used to compare the results. Compared with the DVDI, the CFAI underestimated the evaluation results. The CFAI can respond well to the degree of crop impact after flooding, providing new ideas and reference standards for agriculture-related departments. [ABSTRACT FROM AUTHOR]

Objective To investigate the relation between 18F-FDG PET/CT metabolic parameters and the clinicopathological characteristics of colorectal cancer (CRC) patients. Methods We included 358 CRC patients who met the admission criteria. 18F-FDG PET/CT scans were performed before any treatment. Maximum standard uptake, average standard uptake, tumor metabolic volume (MTV) and total glycolysis (TLG) of the primary lesion of CRC were measured and calculated. The correlation of metabolic parameters with lesion location, pathological profile and TNM staging were investigated through Mann-Whitney U test and Kruskal-Wallis test. Results The MTV and TLG values in the primary foci of colon cancer were the highest, followed by sigmoid cancer and the lowest in rectal cancer, with statistically significant differences between the groups (P < 0.001). SUVmax values of poorly/poorly-moderately differentiated colorectal cancer were higher than those of moderately/well differentiated colorectal cancer (P=0.028). MTV values of primary mucinous adenocarcinoma were higher than those of primary adenocarcinoma (P=0.023). MTV and TLG values were higher in T4 lesions than those in T2-3 lesions (P=0.0001, P=0.007); SUVmax and SUVmean values of sigmoid carcinoma with distant metastasis were lower than those without distant metastasis(P=0.015, P=0.011). Conclusion The metabolic parameters of CRC are correlated with the lesion location, pathological features and TNM staging, which could partly reflect the pathological characteristics and heterogeneity of CRC.

Objective: The present study investigated the predictive diseases progression value of preoperative fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with local advanced cervical cancer (LACC). Methods: In total, 267 patients [median age 58 (range: 27–85) years old] with LACC underwent 18F-FDG PET/CT prior to any treatment. The maximum standardized uptake values (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary lesion and metastatic lymph nodes were measured on PET/CT and correlated with clinicopathological features and progression-free survival (PFS). Results: The median follow-up was 36.52 (range: 3.09–61.29) months. During the observation period, 80 (30.0%) patients exhibited disease progression. Univariate analysis showed that FIGO stage, concurrent chemoradiotherapy (CRT), serum level of carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCC-Ag), primary tumor MTV (pMTV) and TLG (pTLG), lymph nodes SUVmax (nSUVmax) and TLG (nTLG), and total metabolic activity (sMTV, sTLG) were associated with PFS. nSUVmax ≥ 5.29, CEA ≥ 7.11 ng/ml and deficiency of concurrent CRT were independent risk factor for PFS (p = 0.006, p = 0.008, p = 0.014). The 3-year PFS for patients with high nSUVmax were 42.2% compared to 56.3% for low nSUVmax values. Conclusion: Pretreatment cervical and lymph nodes metabolic parameters were associated with PFS in patients with LACC. [ABSTRACT FROM AUTHOR]

Remote sensing inversion technology can be used for water quality parameter inversion to realize water quality monitoring in large scale space. The current research on water quality parameter inversion is only for a single satellite. In order to make full use of satellite image resources, the remote sensing images of GF-1B \ C \ D satellite group are taken as the research object. The Mulan River is taken as the research area. The linear regression method is used to construct the regression equations of total phosphorus and ammonia nitrogen, and the inversion model of total phosphorus and ammonia nitrogen is determined according the evaluation parameters. The MSE of the total phosphorus inversion model is 0.049, and the correlation between the inversion value and the measured value is 0.701. The MSE of the ammonia nitrogen inversion model is 0.063, and the correlation between the inversion value and the measured value is 0.813. These data show that the inversion effect is good. The inversion models are applied to the GF-1D satellite remote sensing image on March 15, 2021 to obtain the large-scale spatial distribution maps of total phosphorus concentration and ammonia nitrogen concentration. The water quality classification maps of the the Mulan River in Putian urban area are obtained too, which are convenient for further analysis and evaluation of the water quality. [ABSTRACT FROM AUTHOR]

In order to solve the problem of three-band bandpass signal aliasing, a delay-adjustable third-order bandpass sampling structure is proposed. By designing a digital anti-aliasing filter, the alias-free reception of three-band bandpass signals can be realized. The simulation results are given, the signal is reconstructed and the anti-aliasing performance is analyzed. After the three-passband signal passes through the anti-aliasing filter, the signal output signal-to-noise ratio can be above 28 dB. This method solves the bandpass. The multi-signal aliasing problem in sampling increases the sampling frequency selection range, which reduces the hardware burden and improves the flexibility of the software radio.

In order to solve the problems of low production efficiency, poor quality of blanks, high labour intensity and inability to meet the market demand with the manual gypsum mould, a novel design of the gypsum mould to be applied into the automatic production of the planks was developed for ceramic handicrafts. This mould inherits the advantages of the manual mould with tenon–mortise connection and adopts six-piece combination. According to the spherical radial movement, the new mould opens and closes, mostly avoiding movement interference and significantly improving service life. The connection technique of ‘six-point positioning principle’ was proposed and adopted to embed the connection device of four side die pieces with manipulator, so as to realise the strength of gypsum die pieces and effectively connect with the manipulator. Based on the group technique, the standard eigenvector and norm for the grouping of geometric elements of target blanks were proposed to realise the grouping of many different kinds of blanks into a few number of groups with all the blanks. Within a group, the gypsum mould keeps the external geometric features and tenon–mortise connection unchanged, while the working cavity of different blanks only alters, for the flexibility of gypsum mould. Thus, the universality of the mould is gained, and the design and manufacturing efficiency is greatly improved, with the considerable reduction of the cost, and the digitisation of design, manufacturing and management processes is realised. The gypsum mould provides a new technological method and technical guarantee for changing the labour-intensive production mode of ceramic handicraft blank cast and forming, realising the intellectualisation and automation of the main production link of ceramic handicraft blank cast and efficiency automatic and intellectualised production of ceramic handicraft blank with high identity.