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Accurate knowledge point sequences and clear learning paths are the compass for learners to travel in the sea of massive knowledge, they can point out the way for learners and improve their learning experience. Generating knowledge point sequences and learning paths based on knowledge reasoning is conductive to optimizing the allocation of educational resources and improving the quality of higher education, and this has a profound influence on the reform of the entire educational field. In view of this, this study explored the generation of knowledge point sequences and the recommendation of learning paths based on knowledge reasoning. At first, the learning behavior of learners was subjected to collaborative analysis based on three aspects of knowledge points: learning frequency, learning duration, and pause/ skip frequency, and the specific method of generating subject knowledge point sequences based on the metrics of difficulty differences was given. Then, a sequence sampling method that matches the features of Entity-Relationship (ER) diagram was proposed, which enables the system to dynamically adjust the recommended knowledge points and learning paths according to learners’ learning progress with the help of biased random walks, thereby giving personalized and dynamic learning recommendations. At last, the validity of the proposed method was verified by experimental results. [ABSTRACT FROM AUTHOR]

The increasing production of Citri Reticulatae Pericarpium (Chenpi) has led to a surge in the generation of citrus pulp byproducts; however, its recycling remains inadequate due to rapid spoilage. Developing sustainable storage methods to facilitate recycling initiatives is essential. In this study, a newly isolated strain, Geotrichum candidum AGRC-GC1, characterized by its robust ability to occupy ecological niches and suppress other microorganisms, was employed to inhibit spoilage in citrus pulp. AGRC-GC1 rapidly colonized the pulp, comprising 98.5% of the fungal microbiota, thereby protecting it from invasion by spoilage microorganisms including Saccharomyces , Torulaspora , Podosphaera , and Aureobasidium. This colonization slowed sugar consumption, preventing acidification and maintaining a pH of 3.86, compared to a control value of 3.48. Key molecules associated with the sour odor of spoilage, namely 3-aminoisobutyric acid (AIBA) and D-gluconic acid (GA), were significantly reduced by AGRC-GC1 treatment, effectively eliminating the sour odor. Additionally, two esters, glycerol-AIBA and erythritol-GA, were found to exhibit a strong sour odor associated with spoilage. Furthermore, AGRC-GC1 demonstrated the ability to synthesize a 3.45-fold increase in tyrosol, which enhanced the antioxidant activity in the pulp. Moreover, AGRC-GC1 regulated water activity by synthesizing glucitol and erythritol, with increases of 11.11- and 2.27-fold, respectively. These findings offer new insights into the citrus spoilage process in natural environments and highlight the potential of AGRC-GC1 in the recycling and utilization of citrus pulp byproducts. [Display omitted] • AGRC-GC1 was identified to prevent the spoilage of citrus pulp. • AGRC-GC1 quickly seized the ecological niche and inhibited spoilage microorganisms. • Glycerol-AIBA and erythritol-GA were identified as the spoilage odor molecules. • Tyrosol was produced by AGRC-GC1 to maintain the antioxidant activity in pulp. • Glucitol and erythritol were produced to maintain the water activity in pulp. [ABSTRACT FROM AUTHOR]

While gold is a stable metal in water, it is not uncommon for microfluidic experimenters using biologically-relevant fluids such as phosphate-buffered saline (PBS) to witness their precious gold electrodes quickly vanish from the microchannel once the voltage exceeds a few volts. This stability issue concerns multiple fields where high voltage provides superior actuator or sensor performance, such as resistive pulse sensing (RPS), electroosmosis, electrowetting and so on. One solution to protect metallic electrodes is using alternative voltages (AV) as opposed to continuous voltages. After recalling that gold dissolution is enabled by the chloride ions present in most biologically-relevant solutions, we explore the stability conditions of the electrodes for voltages from 1 to 20 Vpp (Peak to Peak voltage amplitude), actuation frequencies between 0 and 5 kHz, and for various pH and electrolytes (NaCl, Na2SO4, HCl). We find that the dissolution threshold voltage depends on the ratio of reaction to diffusion rate given by the Damkhöler number Da. In mass-transfer limited regime, the dissolution threshold is independent of the frequency, whereas the dissolution voltage is observed to grow as Da-1/2 in the reaction limited regime. These findings provide guidelines to design more reliable electrowetting, electroosmosis, dielectrophoresis and resistive pulse sensing devices. [ABSTRACT FROM AUTHOR]

This research takes a certain polluted section of Danjiangkou Reservoir as the research object. First, perform SS and COD determinations on the collected water samples, extract DNA from planktonic microorganisms and attached microorganisms, and then perform conventional PCR on 16SrDNA that is highly conserved and maintains a highly "family specific" sequence or structure during the long-term evolution of microorganisms. Amplification and purification. Through the detection of the absolute number of microorganisms, the identification of species, and the routine tests of the water quality of the contaminated river section, the relationship between the species of microorganisms and the spatial change of water quality is explored, reflecting the effect of microorganisms on water purification from another perspective. The research results show that: in a certain pollution section, the structure of attached microorganisms is relatively simple; the upstream has been polluted. The plankton microorganisms multiply in the area of 50-100 m in the vertical direction and 20-90 m in the horizontal direction, and the number of attached microorganisms peaks at 100 m downstream, which is 46.1 pg/pl. The TN content exceeds 1.00 mg/L, which is the IV standard for surface water. The correlation analysis between bacterial communities and environmental factors showed that TN (R=-0.7523, PA).001 is an important factor affecting the distribution of bacteria. Firmicutes (RAI.671. P=0.006), Planctomycetes (RAI.709. PA). 003) was positively correlated with TN, and Actinobacteria was positively correlated with NH4-N (RAI.582. P 0.023). [ABSTRACT FROM AUTHOR]

Lake microorganisms are an important part of the aquatic ecosystem, which can directly or indirectly affect the material and energy cycles of the aquatic ecosystem. Danjiangkou Reservoir is the water source area of the Middle Route of the South-to-North Water Transfer Project. Its water quality directly affects the drinking water quality of more than 100 million people along the way. Therefore, long-term monitoring of the microbial community composition of Danjiangkou Reservoir is of great significance. However, relatively little work has been carried out at present. In order to explore the diversity of bacterial communities in areas with different nutritional levels, high-throughput sequencing was used to analyze the diversity of bacterial communities, to study the composition and distribution characteristics of bacterial communities, with a view to discovering the ecological com-position of the microbial community in Danjiang-kou Reservoir, its influencing factors, and discussing the composition of floating bacteria, the relationship between its abundance and physical and chemical factors of water quality, in order to establish a biological indicator method suitable for Dan-jiangkou Reservoir water quality, sequence the 16SrDNA gene of bacteria, and provide a reference for Danjiangkou Reservoir water environmental protection. The results found: The water quality of Danjiangkou Reservoir is generally good. However, due to pollution from agricultural non-point sources and domestic sewage in villages and towns, total nitrogen (TN) has significantly exceeded the standard. There are differences in the composition of the dominant bacterial community at different sampling points. The total sequence of Gammaproteobacteria, Holophagae, Alphaproteobacteria, Oxyphoto-bacteria, Bacteroidia, Acidimicrobiia, Actinobacte-ria accounts for about 90% of the total sequence, and these bacteria are the dominant group. At HJW, Gammaproteobacteria is as high as 39.63%. The dilution curve reflects that the OTUs generated by clustering at each sampling point are BSZ>TBDq>HZW>BX. This experiment has a comprehensive and accurate understanding of the composition of the planktonic bacterial community in the Danjiangkou reservoir area. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text Objective: To develop a nomogram to estimate the risk of SPLD (International Study Group of Liver Surgery definition grade B or C) and long-term survival in patients with HCC before hepatectomy. Background: SPLD is the leading cause of post-hepatectomy mortality. The decision to refer an HCC patient for hepatectomy is mainly based on the survival benefit and SPLD risk. Prediction of SPLD risk before hepatectomy is of great significance. Methods: A total of 2071 consecutive patients undergoing hepatectomy for HCC were recruited and randomly divided into the development cohort (n = 1036) and internal validation cohort (n = 1035). Five hundred ninety patients from another center were enrolled as the external validation cohort. A nomogram was developed based on independent preoperative predictors of SPLD determined in multivariable logistic regression analysis. Results: The SPLD incidences in the development, internal, and external validation cohorts were 10.1%, 9.5%, and 8.6%, respectively. Multivariable analysis identified total bilirubin, albumin, gamma-glutamyl transpeptidase, prothrombin time, clinically significant portal hypertension, and major resection as independent predictors for SPLD. Incorporating these variables, the nomogram showed good concordance statistics of 0.883, 0.851, and 0.856, respectively in predicting SPLD in the 3 cohorts. Its predictive performance in SPLD, 90-day mortality, and overall survival (OS) outperformed Child-Pugh, model for end-stage liver disease, albumin-bilirubin, and European Association for the Study of the Liver recommended algorithm. With a nomogram score of 137, patients were stratified into low and high risk of SPLD. High-risk patients also had decreased OS. Conclusions: The nomogram showed good performance in predicting both SPLD and OS. It could help surgeons select suitable HCC patients for hepatectomy. [ABSTRACT FROM AUTHOR]

Posthepatectomy liver failure is a worrisome complication after major hepatectomy for hepatocellular carcinoma and is the leading cause of postoperative mortality. Recommendations for hepatectomy for hepatocellular carcinoma are based on the risk of severe posthepatectomy liver failure, and accurately predicting posthepatectomy liver failure risk before undertaking major hepatectomy is of great significance. Thus, herein, we aimed to establish and validate an artificial neural network model to predict severe posthepatectomy liver failure in patients with hepatocellular carcinoma who underwent hemihepatectomy. Three hundred and fifty-three patients who underwent hemihepatectomy for hepatocellular carcinoma were included. We randomly divided the patients into a development set (n = 265, 75%) and a validation set (n = 88, 25%). Multivariate logistic analysis facilitated identification of independent variables that we incorporated into the artificial neural network model to predict severe posthepatectomy liver failure in the development set and then verified in the validation set. The morbidity of patients with severe posthepatectomy liver failure in the development and validation sets was 24.9% and 23.9%, respectively. Multivariate analysis revealed that platelet count, prothrombin time, total bilirubin, aspartate aminotransferase, and standardized future liver remnant were all significant predictors of severe posthepatectomy liver failure. Incorporating these factors, the artificial neural network model showed satisfactory area under the receiver operating characteristic curve for the development set of 0.880 (95% confidence interval, 0.836–0.925) and for the validation set of 0.876 (95% confidence interval, 0.801–0.950) in predicting severe posthepatectomy liver failure and achieved well-fitted calibration ability. The predictive performance of the artificial neural network model for severe posthepatectomy liver failure outperformed the traditional logistic regression model and commonly used scoring systems. Moreover, stratification into 3 risk groups highlighted significant differences between the incidences and grades of posthepatectomy liver failure. The artificial neural network model accurately predicted the risk of severe posthepatectomy liver failure in patients with hepatocellular carcinoma who underwent hemihepatectomy. Our artificial neural network model might help surgeons identify intermediate and high-risk patients to facilitate earlier interventions. [ABSTRACT FROM AUTHOR]

Purpose: Family with sequence similarity 83 member H (FAM83H) plays key roles in tumorigenesis. However, the specific roles of FAM83H in cervical cancer (CC) have not been well studied. Materials and Methods: The RNA-seq data of 306 CC tissues and three normal samples downloaded from The Cancer Genome Atlas were used to analyze the expression of FAM83H. The Kaplan-Meier method was used to draw survival curves. Associations between FAM83H expression and clinicopathological factors were analyzed by chi-square test. Cox proportional hazards model was used to analyze prognostic factors. Loss-of-function assays were conducted to discover the biological functions of FAM83H in cell proliferation, colony formation, invasion, and migration. Real-time Quantitative Reverse Transcription PCR (qRT-PCR) and Western blotting were used to measure the expression levels of FAM83H in CC cell lines. Results: Our results demonstrated that FAM83H is overexpressed in CC tissues and that high FAM83H expression is associated with worse overall survival (OS). High FAM83H expression in CC was associated with clinical stage, pathologic tumor, and pathologic node. Univariate analysis suggested that FAM83H expression was significantly related to the OS of CC patients. Although multivariate analysis showed that FAM83H expression was not an independent prognostic factor for the OS of CC patients, the effects of FAM83H on CC cell growth and motility was significant. Loss-of-function experiments demonstrated that knockdown of FAM83H inhibited proliferation, colony formation, migration, and invasion of CC cells by inactivating PI3K/AKT pathway. Conclusion: FAM83H might play a crucial role in CC progression and could act as a novel therapeutic target in CC. [ABSTRACT FROM AUTHOR]

Aluminum flocculants can improve the flocculation performance of activated sludge (AS). This study systematically investigated the influence of Al3+ dosage on AS flocculation and explored its underlying mechanism by total interaction energy (Wtot) and loosely-bound extracellular polymeric substances (LB-EPS) content. AS samples cultivated in a sequencing batch reactor (SBR) were added a range of Al3+ dosages: 0, 0.0625, 0.125, 0.25, 0.5, 1, 2, and 4 mEq.L-1. As Al3+ dosage increased from 0 to 2 mEq.L-1, Wtot, LB-EPS content and supernatant turbidity all decreased, which appeared as better AS flocculation. However, when Al3+ dosage further increased to 4 mEq.L-1, Wtot and LB-EPS content decreased, whereas supernatant turbidity tended to increase and AS flocculation deteriorated. Most of the added Al3+ distributed within the pellet at all Al3+ dosages, which is the core element governing the differences in AS flocculation performance. This study together with our previous findings are the first time to uncover that Wtot, LB-EPS content, supernatant turbidity decreased in two-phases: 0-0.25 VS. 0.25-2 mEq.L-1 Al3+ dosages as the concentration of added Al3+ in the pellet increased, whereas high dosage (4 mEq.L-1) deviated from the tendency. [ABSTRACT FROM AUTHOR]

Abstract: The composite piezomagnetic film was prepared by using Fe73.5CulNb1.5Si13.5B9Mo1.5 amorphous powder with particles size of 40 μm as dispersing agent and silicon rubber as the matrix. Meanwhile, the Fe73.5CulNb3Si13.5B9 amorphous ribbon was selected as piezoelectric layer. The testing frequency was ranged from 10 kHz to 1 MHz, and the pressure stress was from 0 to 0.14 MPa. The tiny stress impedance (TST) effects of the two types of layer structures were compared in the experiment, the two types included piezomagnetic/piezoelectric/piezomagnetic (pm/pe/pm) layer and piezoelectric/piezomagnetic/piezoelectric (pe/pm/pe) layer. It is found that both of the layer structures have magnetoelectricity coupling effects. The magnetoelectricity coupling effect enhances with the increase of pressure stress before 0.02 MPa, and afterward the magnetoelectricity coupling effect comes to a maximum value, which has little contribution to TSI. Since two types of layer structure are both of varying magnetoelectricity coupling effect, pm/pe/pm is piezomagnetic based and pe/pm/pe is piezoelectric based. [Copyright &y& Elsevier]