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The prediction of basin water quality has become an urgent need for water environment management, where water pollution is on the increase. Currently, physical models are primarily used for water quality predictions, but the models are not adaptable for the automatic future prediction of watershed water quality owing to their non-automatic boundary setting. The development of big data, which has led to artificial intelligence (AI) technology, has remedied the deficiency of physical models and has been widely used in water quality prediction. However, the accuracy of AI models depends only on the quantity and quality of dataset, which is applied on specific and discrete sections with enough data and difficult to extend to regions with limited monitoring data. Thus, we constructed migration and distribution gates to express the spatial influence of different variables from different sections on the water quality of a specific and discrete section. The temporal processes were expressed by degradation equation. The migration gate, distribution gate and degradation equations were incorporated into Long Short-Term Memory Network (LSTM) to improve the operation mechanism of the LSTM algorithm to create the Im-LSTM model, which considers both the temporal influence of a specific section and the spatial influence of other sections on a specific section at basin scale. Compared to ANN, LSTM, Im-LSTM showed the best performance for basin water quality prediction, especially for mainstream sections at sudden pollution process. Thus, the proposed Im-LSTM provides a new approach for water environment supervision. [ABSTRACT FROM AUTHOR]

The effects of different forming process on the microstructure, martensitic transformation, and mechanical properties of the Ni50Mn34In14Co2 (numbers indicate at.%) alloys were investigated in detail. The results show that the microstructure of Ni50Mn34In14Co2 alloy consists of the matrix and the second phase by powder hot forging technology under the forces in different directions and spark plasma sintering (SPS), and the prepared sample has obvious preferred orientation by applied force in the three directions. The grain and the second phase of prepared sample were obviously refined by the hot forging technology. The martensitic transformation behavior was almost unchanged by different forming process. In addition, the shape memory effect of prepared Ni50Mn34In14Co2 alloy was significantly enhanced by different forming processes. [ABSTRACT FROM AUTHOR]

Effects of aggregate size and shape on monotonic shear behaviour of unreinforced and geogrid-reinforced aggregate interfaces were systematically investigated through direct shear tests. Five different grades of angular aggregates and five kinds of rounded aggregates with identical particle size distribution were selected as test materials. Experiment results revealed the coupling effects of particle shape and aperture ratio (AS/D50), defined as the ratio of geogrid aperture size (AS) to the average particle size of aggregate (D50), on the shear behaviour of the unreinforced and reinforced interfaces. The peak shear stress, shear displacements corresponding to peak shear stress and residual shear stress, as well as maximum dilation of aggregate–geogrid interfaces at each AS/D50 were greater than those of glass beads–geogrid interfaces. The largest interface shear strength coefficient of aggregate–geogrid interfaces was achieved at AS/D50 = 2.55, and the optimum reinforcement of glass beads–geogrid interfaces appeared at AS/D50 = 5.05. The shear strength decreased more after the peak when the value of AS/D50 was relatively small, and the post-peak strength reduction of aggregate–geogrid interfaces was more pronounced. A generalised stress-dilatancy relationship was proposed, which introduced a variable dilatancy index (ζ) that reflected the effects of aperture ratio and particle shape. [ABSTRACT FROM AUTHOR]

Reinforced soil structures are often subjected to both static and dynamic loads. However, experimental data concerning the interaction of soil–geosynthetic interfaces under normal dynamic loads are scarce. This paper reports on a series of large-scale direct shear tests that are used to investigate the shear behaviour of a gravelly soil–geogrid interface under normal cyclic load (NCL) conditions. The results show that the shear stress magnitude under NCL conditions is generally between the shear stresses under normal static load (NSL) conditions corresponding to the upper and lower bounds of the NCL. The upper and lower envelopes of the shear stress–displacement curve increase with increasing initial stress and amplitude. The enhancement coefficient ( α) is used to describe the degree of influence of the additional cyclic load on the shear stress of the interfaces. The relative time shift between the shear stress ratio ( R NCL ) and the normal stress ( σ n ) is nearly a constant of 0.5 cycles, and the influence of the initial stress on the stress ratio is opposite to that of the amplitude. Finally, the volume change response is discussed under different normal load conditions. [ABSTRACT FROM AUTHOR]

Objective: To investigate the value of inflammation,coagulation and nutrition markers in predicting the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation for treatment of periprosthetic joint infection(PJI). Methods: A retrospective study was conducted on 70 patients who undertook prosthesis removal and antibiotic-loaded bone cement spacer implantation due to PJI from June 2016 to October 2020 in the Department of Orthopedics,Henan Provincial People's Hospital. There were 28 males and 42 females,aged (65.5±11.9) years (range: 37 to 88 years). Patients were divided into two groups as the successful group and the failed group depended on whether reinfection occurred after prosthesis removal and antibiotic-loaded bone cement spacer implantation at the last follow up. Patient demographics,laboratory values (C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),ESR and CRP ratio (ESR/CRP),white blood cell count(WBC),platelet count(PLT),hemoglobin(HB),total lymphocyte count(TLC),albumin、fibrinogen(FIB),CRP and albumin ratio (CAR),prognostic nutritional index(PNI)),and reinfection rates were assessed. Comparison between groups was conducted by the independent sample t test or χ 2 test. Receiver operating characteristic (ROC) curve was plotted,and the area under the curve (AUC),optimal diagnostic threshold,sensitivity,and specificity were analyzed to predict the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation. Results: All patients were followed up for at least two years,and the follow-up time was (38.4±15.2) months (range: 24 to 66 months). Fifteen patients suffered failure after prosthesis removal and antibiotic-loaded bone cement spacer implantation,while the other 55 patients succeeded. The overall failure rate of prosthesis removal and antibiotic-loaded bone cement spacer implantation in PJI treatment was 21.4%. Level of preoperative CRP ((35.9±16.2)mg/L),PLT ((280.0±104.0)×10 9 /L) and CAR (1.3±0.8) in successful group were lower than CRP ((71.7±47.3)mg/L),PLT ((364.7±119.3)×10 9 /L) and CAR (2.5±2.0) in failed group (all P <0.05).Whereas,level of preoperative ESR/CRP (3.3±3.1), Albumin ((35.3±5.2)g/L) and PNI (43.6±6.2) in successful group were higher than ESR/CRP (1.6±1.4),Albumin ((31.3±4.8)g/L) and PNI (39.2±15.1) in failed group (all P <0.05). AUC of ROC curve,optimal threshold value,sensitivity and specificity of CRP,ESR/CRP, PLT, Albumin,CAR and PNI for the predicting failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation were 0.776(95% CI :0.660 to 0.867),35.4 mg/L,86.7%,67.3%;0.725(95% CI :0.605 to 0.825),1.0,60.0%,78.2%;0.713(95% CI :0.593 to 0.815),253,93.3%,47.3%;0.721(95% CI :0.601 to 0.822),35.7,93.3%,49.1%;0.772(95% CI :0.656 to 0.863),1.1,86.7%,67.3%;0.706(95% CI :0.585 to 0.809),45.7,100%,41.8% respectively. Conclusion: In patients with PJI,CRP>35.4,ESR/CRP≤1.0 and CAR>1.1 could predict the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation.

With characteristics of high infectivity, diverse transmission routes and high variation, norovirus is the main pathogen of sporadic cases and outbreaks of acute gastroenteritis, resulting in a serious disease burden. This paper summarizes the latest progress in epidemiological research of norovirus infection from aspects of disease burden caused by acute gastroenteritis, virus variation and predominant strains, prevention and control measures, and immunization and vaccine development.

Objective: To evaluate the application of real-time RT-PCR and semi-nested RT-PCR in the detection of norovirus in oysters and analyzing the genetic characteristics of the isolates. Methods: Real-time fluorescent RT-PCR and semi-nested RT-PCR were used to detect norovirus GⅠ/GⅡ in fresh oysters collected from the markets in Beijing from November 2014 to October 2015. The detection rate of the parallel test was also analyzed. In addition, the reliability of semi-nested RT-PCR was evaluated by agreement rate and consistency test (Kappa value). The positive products of norovirus GⅠ/GⅡ capsid protein region gene by semi-nested RT-PCR were sequenced. Software BioEdit 7.0.9.0 was used for sequence alignment, and software Mega 6.0 was used to construct the evolutionary tree. Results: In 72 samples, the detection rate of norovirus was 31.94% (23/72) by real-time RT-PCR, 38.89% (28/72) by semi-nested RT-PCR and 48.61% (35/72) by parallel test. The coincidence rate of the two methods was 73.61%, a moderate degree (Kappa value =0.43). A total of 13 norovirus strains were successfully sequenced, and 11 strains (7 GⅡ.17 strains, 2 GⅡ. 4 Sydney&#95; 2012 strains, 1 GⅡ. 1 strain and 1 GⅡ. 21 strain) were obtained from norovirus positive samples by two RT-PCR methods, two strains (1 GⅡ. 17 strain and 1 GⅡ. 3 strain) were obtained from real-time RT-PCR negative samples which were positive for norovirus by semi-nested RT-PCR. The similarity between these strains and reference strains from diarrhea patients, environmental sewage, and shellfish products were 84.4% - 100.0%. Conclusions: The parallel test of norovirus in oysters by two RT-PCR methods can improve the detection rate and detect more genotypes. Norovirus strains in oysters were highly homologous with reference strains from diarrheal patients, environmental sewage, and shellfish products. Therefore, surveillance, prevention and control for norovirus should be carried out in people who have frequent contacts with oysters and related environments.