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To solve problems of the low yields and dark color of Sargassum horneri polysaccharides which were produced according to the traditional extraction method under the high-temperature and alkalic condition, this study attempted to produce S. horneri polysaccharides at a lower alkaline treatment temperature of 60 ℃ and optimize the process parameters by the response surface methodology. The combined scores of alginate and fucoidan yields and whiteness index (WI) were used as assessment indices to identify the optimal process condition. Under the optimal extraction condition, the concentration of NaClO addition was changed to investigate its effect on various characteristics of the produced alginate and fucoidan. The results showed that the polysaccharide comprehensive score was significantly correlated with the alkaline concentration, the extraction time, and the dosage of NaClO (P

In order to establish the standard preparation methodology for bioactive polysaccharide of fucoidan, this study carried out the research of preparation method of fucoidan from Saccharina japonica. Three extraction methods, high temperature pressure extraction (HPE), acid extraction (AE), and microwave extraction at 400 W (M400 W), 500 W (M500 W), and 600 W (M600 W) were selected. Subsequently, two precipitation methods, calcium chloride precipitation (CP) and ethanol precipitation (GAP) were used to remove alginate followed by finally precipitation of fucoidan with high concentration ethanol. Fucoidan extracts prepared in totally ten different conditions were collected, of which the contents of total sugar, total phenols, protein, uronic acid, and sulfate groups were analyzed. Meanwhile their antioxidant activities including Fe3+ reduction ability, ABTS+ and DPPH free radical scavenging ability were determined. The correlation analysis was conducted based on the above determined results to discover the relationship between preparation methods and fucoidan qualities. Accordingly, the preparation methods for fucoidan of high yield, high purity, and excellent antioxidant activities were selected. Results showed that the yields of fucoidan by acid extraction with calcium precipitation (AE-CP) and microwave extraction with calcium precipitation (M400 W-CP, M500 W-CP, M600 W-CP) were 3.821%, 3.516%, 3.376%, and 2.998%, respectively. Meanwhile, the sulfate content was 17.734%, 23.872%, 23.376%, and 22.149%, respectively. Their protein and total phenol content were below 1%, the uronic acid content was below 10%, and the Trolox equivalent (ABTS+ radical scavenging ability) was 5.637, 5.336, 6.567, and 5.616 μg/mg, respectively. Thus, the above four preparation conditions were ideal for processing of fucoidan, among which the method of microwave extraction followed by calcium precipitation showed advantages of short processing time and low solvent consumption that met the requirement of the environmental-friendly processing. This study systematically investigated the effects of preparation methods on the yield and quality of fucoidan, which provided a practical preparation methodology for fucoidan from Saccharina japonica with high yield, purity and antioxidant activity.

Objective: To improve the contents of various hypoglycemic components in natural mulberry leaves, different fermentation-promoting substances were added to mulberry leaf shoots during their fermentation by means of that drawn on the experience of traditional black tea fermentation process. Method: Based on the single factor experiments, orthogonal optimization test was carried out to determine the optimal addition amount using cellulase, pectinase and tea polyphenols as influencing factors, and the contents of total alkaloids, total flavonoids and total polysaccharides in mulberry leaves as comprehensive evaluation indicators. Results: Compared with natural fermentation, the contents of total alkaloids, total flavonoids and total polysaccharides in mulberry leaves fermented by additives were increased by 61.84%, 45.02% and 28.68%, when the addition amounts of cellulase, pectinase and tea polyphenols were 0.6%, 0.8% and 0.9%, respectively. And their contents were 115.12%, 80.19% and 54.81% higher than those in natural mulberry leaves, respectively. Conclusion: The contents of hypoglycemic components in natural mulberry leaves can be improved by adding substances that promote fermentation, which lays a foundation for its subsequent effective utilization in hypoglycemia.

The Dongsheng Coalfield in Ordos is a Jurassic coal bearing formation, and the 2-2 and 3-1 coal seams in many deep mining areas can be mined in the whole area, and the spacing of coal seams is small. This paper takes Yingpanhao Coal Mine as a geological prototype, and constructs a numerical model of the research area through FLAC3D and UDEC numerical simulation software to study the surface movement deformation and the evolution law of stress field caused by mining coal seams 2-2 and 3-1. The results show that repeated mining in multiple coal seams will cause the central projection of the subsidence basin to move toward the direction of lower coal seam, and then approach the central projection of the initial mining of the upper coal seam, and ultimately cross it; after the two coal seams were continuously mined, the maximum subsidence value of the surface is less than the sum of the maximum subsidence values caused by mining the two coal seams separately, and the subsidence coefficient of the coal seam repeated mining is less than the initial mining subsidence coefficient; coal pillar dislocation is closely related to surface movement parameters, the staggered coefficient is related to the surface subsidence coefficient, horizontal movement coefficient, and the tangent of the main influencing angle in a logarithmic normal function, concave parabolic function, and convex parabolic function, respectively; as common factors, pillar staggered distance and width-depth ratio have coupling effects on the ratio of characteristic parameters of primary mining and repeated mining in coal seam; in addition, with the increase of pillar staggered distance, the surface subsidence basin area decreases first and then increases, and the contours of horizontal movement near the basin evolve from ellipse to shuttle; the optimal staggered distance of multi-coal seam mining in this study area is 30 m based on the empirical formula of pressure relief distance, the surface damage degree and the relief effect of staggered mining.

The method, which combines Sentence-BERT and LDA, takes the topic number of LDA as the k value in K-means algorithm, resulting in poor interpretability and low topic consistency. To solve this problem, a Sentence-BERT and LDA optimization method based on density Canopy(SBERT-LDA-DC) was proposed, which used density Canopy to improve the K-means algorithm. The experimental results indicate that this method is superior to similar methods using K-means and K-means++ to cluster feature vectors on the consistency index. Compared with the SBERT-LDA method, the consistency index is improved by 229% on the 1 852 drama comment dataset. The proposed SBERT-LDA-DC method is effective, which provides a new method for product or service providers to better understand user opinions and improve their own products or services, and has strong practical application value.

The important factors that affect the water inrush level in mines are the intensity of water inrush, mine roadways and mine goafs. In order to study the characteristics and influencing factors of internal water level changes in the process of water filling in goafs after mine water inrush, an experimental platform was built to conduct experimental research on water filling in goafs. The results show that: under the blocking effect of gangue on water flow, the water filling process of the goaf is divided into the initial water flow spreading stage and the subsequent water filling stage. In the whole process, the water level near the working face is higher while the deep water level is lower, and the water surface slope appears and gradually decreases with time; the water filling rate of goaf increases with time and approximates a quadratic function change. Water inrush and mine spatial structure are important factors affecting the water filling process.

This is a paper in the field of metallurgical engineering. In this paper, natural clay mineral serpentine was subjected to mechanochemical activation (MA) for the highly-efficient removal of Ni (Ⅱ) in wastewater and simultaneous recovery of metal nickel as secondary resources. The effectiveness of serpentine for precipitation and recovery of Ni was investigated, with the process mechanism analyzed. The results showed MA of serpentine led to the disordering of the stable crystal structure of serpentine, thereby resulting in the release of large amounts of Mg2+ ions and hydroxyl group in aqueous solution, and the resultant interaction between Ni (Ⅱ) and OH-, with the formation of amorphous Ni(OH)2 as sediments. The maximum processing capacity of activated serpentine for Ni (Ⅱ) reached up to 226.04 mg/g, meanwhile the final Ni (Ⅱ) concentration met up with the national discharging standard, indicating the feasibility of remediation of heavy metal contaminations by a very low dosage of activated serpentine. Concluded from these results, mechanochemical activation can be expected to boost the reactivity of natural serpentine, thereby improving the utilization efficiency of low-cost serpentine for the clean-up of environment pollutions and recovery of metal resources, which is conducive to promoting the green development of mineral-resource-environment cross-fields.

Coronavirus disease 2019 (COVID-19) is the most widely spread epidemic in the past century, which poses a major threat to the safety and health of the whole population, especially to those of the elderly. China carried forward the traditional virtue of respecting and caring for the elderly in special times, adhered to unified leadership, joint prevention and control, society-wide prevention and control, and precise measure implementation for the elderly in the face of challenges such as poor physical and mental health, weak protection ability, and the "digital divide". During the period of COVID-19 prevention and control, China did its utmost to ensure life support and health service for old people. In this article, we summarized successful experience of COVID-19 epidemic prevention and control among the elderly in China and proposed some suggestions on improving health service system for elderly and constructing an elderly friendly society during the period of normalized COVID-19 epidemic prevention and control.

In this paper, the gel properties of sodium alginate with Y3+, Ce3+, La3+ and Er3+ were studied. By studying the mechanical properties, equilibrium water content, ion exchange rate and gel mechanism of seaweed rare earth gel, it was found that: The coordination form of rare earth ions and carboxyl group in sodium alginate was pseudo-bridged monodentate coordination and bridge coordination. At the same time, the special three-dimensional network structure of the rare earth gel was formed through the planar and non-planar geometry formed by intramolecular and intermolecular chelation, and the gel strength of the gel formed by La3+, Y3 +, Er3+, Ce3+ and sodium alginate M/G≈1 was between 32 and 41 N, the Young’s modulus was between 14 and 20 N, the elasticity was between 55% and 59%, the equilibrium water content was greater than 93%, the strength of the four gel was Ce3+> Er3+> Y3+> La3+, the elasticity was Ce3+1, the affinity of seaweed rare earth gel was in this order：Er3+>Ce3+>Y3+>La3+. When M/G=0.99≈1 and M/G=0.19 Er3+> Y3+> La3+. Among them, Ce3+, Y3+ and La3+ had a certain preference for G fragment of sodium alginate, and Er3+ had a certain preference for M fragment. This study would lay a theoretical foundation for the intensive processing and utilization of sodium alginate and the development of new functional materials of rare earth elements.

In this study, kelp juice, apple juice and sugar were used as the main raw materials, and Lactobacillus plantarum was applied as the fermentation strain, to develop a fermented kelp-apple compound juice beverage with excellent flavor and natural nutrition. Based on sensory scores, the process optimization of the compound fruit juice beverage was carried out through single factor experiments and orthogonal experiment design. The best formula and fermentation condition of the beverage were as follows: 1:2 volume ratio of kelp juice to apple juice, 3% sucrose addition, 8% Lactobacillus plantarum inoculation, fermentation time 24 hours and temperature 32 ℃. The result of antioxidant activity assay showed that the inhibition rate of DPPH free radical, ABTS+ free radical and total antioxidant capacity of fermented kelp-apple juice beverage were 73.20%, 36.05% and 0.774, respectively. On the whole, both kelp juice and apple juice showed certain antioxidant capacity. Fermentation improved the antioxidant capacity of kelp juice, but reduced the antioxidant capacity of apple juice. However, the fermentation of sole kelp juice had poor taste and flavor. The addition of apple juice and lactic acid produced by fermentation masked the fishy smell of kelp to a certain extent. On the other hand, the addition of kelp juice prevented decline of antioxidant capacity of sole apple juice fermentation. Fermentation of two juices could significantly improve the DPPH free radical scavenging capacity of beverage. This study solved the problem of fishy smell of kelp beverage, explored the antioxidant activity of kelp-apple juice beverage fermentation system, and would provide theoretical basis and practical guidance for the development of kelp-fruit juice beverage.

Functional brain network provides an effective biomarker for understanding brain activation patterns,the development of neurodegenerative diseases,and the structure of brain signaling.How to use priori information to build accurate brain network is particularly important in subsequent applications.A functional brain network construction model based on group similarity constraints was proposed.By introducing a tensor low rank constraint and using the nuclear norm of the tensor,a brain network group with a low rank prior in the group was solved.The group similarity constraints to shrink the solution space of the brain network was used,thus constructing a better functional brain network effectively.For evaluating the performance of the proposed method,the constructed brain network was adopted for the discriminative task of mild cognitive impairment.The experimental results show that the proposed functional brain network modeling method based on group similarity constraints can construct more discriminative brain network.In addition,based on the brain network constructed by the proposed method,the significant connections consistent with previous studies are obtained,and the effectiveness of the proposed method is further verified.

Background and objective In recent years, Da Vinci robot system applied in the treatment of intrathoracic surgery mediastinal diseases become more mature. The aim of this study is to summarize the clinical data about mediastinal lesions of General Hospital of Shenyang Military Region in the past 4 years, then to analyze the treatment effect and promising applications of da Vinci robot system in the surgical treatment of mediastinal lesions. Methods 203 cases of mediastinal lesions were collected from General Hospital of Shenyang Military Region between 2010 and 2013. These patients were divided into two groups da Vinci and video-assisted thoracoscopic surgery (VATS) according to the selection of the treatments. The time in surgery, intraoperative blood loss, postoperative drainage amount within three days after surgery, the period of bearing drainage tubes, hospital stays and hospitalization expense were then compared. Results All patients were successfully operated, the postoperative recovery is good and there is no perioperative death. The different of the time in surgery between two groups is Robots group 82 (20-320) min and thoracoscopic group 89 (35-360) min (P>0.05). The intraoperative blood loss between two groups is robot group 10 (1-100) mL and thoracoscopic group 50 (3-1,500) mL. The postoperative drainage amount within three days after surgery between two groups is robot group 215 (0-2,220) mL and thoracoscopic group 350 (50-1,810) mL. The period of bearing drainage tubes after surgery between two groups is robot group 3 (0-10) d and thoracoscopic group: 5 (1-18) d. The difference of hospital stays between two groups is robot group 7 (2-15) d and thoracoscopic group 9 (2-50) d. The hospitalization expense between two groups is robot group (18,983.6±4,461.2) RMB and thoracoscopic group (9,351.9±2,076.3) RMB (All P

Background and objective A solitary pulmonary nodule (SPN) is defined as a round intraparenchimal lung lesion less than 3 cm in size, not associated with atelectasis or adenopathy. The aim of this study is to learn clinical experience of the treatment of SPN with Da Vinci Surgical System. Methods A total of 9 patients with solitary pulmonary nodules (SPN) less than 3 cm in diameter was treated with Da Vinci Surgical System (Intuitive Surgical, California) in thoracic surgery department from General Hospital of Shenyang Militrary Region from November 2011 to March 2014. This group of patients included 3 males and 6 females, and the mean age was 51±9.9 yr (range: 41-74 yr). Most of the patients were no obvious clinical symptoms (7 cases were found by physical examination, others were with cough and expectoration). Their median medical history was 12 mo (range: 4 d-3 yr). All the lesions of patients were peripheral pulmonary nodules and the mean diameter of those was (1.4±0.6) cm(range: 0.8-2.8 cm). Wedge-shaped resection or lobectomy was performed depending on the result of rapid pathology and systemic lymph node dissection was done for malignant leision. We used general anesthesis with double lumens trachea cannula. We set the patients in lateral decubitus position with jackknife. The patient cart enter from top of the patient. The position of trocars would be set according to the position of lesion. A 12 mm incision was positioned at the 8th intercostal space in the posterior axillary line as vision port, and two 8 mm incisions were positioned at the 5th intercostal space between the anterior axillary line and midclavicular line, and the 8th infrascapular line as robotic instrument ports about 10 cm apart from the vision port. One additional auxiliary small incision for instrument without retracting ribs was set at the 7th intercostal space in the middle axillary line. Results There were 4 benign leisions and 5 malignancies identified. Wedge-shaped resection was performed for 4 patients, lobectomy with systemic lymph node dissection for 3 patients (including 2 right middle lobectomies and 1 left upper lobectomy) and wedge-shaped resection with systemic lymph node dissection for 2 patients of poor lung function. All of the 9 cases were completed with total robotic procedure without conversion. The pathological results included 3 inflammatory pseudotumors, 1 hamartoma, 5 adenocarcinomas. All of the 29 patients were hospital discharged smoothly. The patients were followed up for 0.1-18.5 mo (median 11 mo) without recurrence or metastasis. Conclusion The SPN patients should be given active surgical treatments to improve the diagnose rate as well as the cure rate of early non-small cell lung cancer. Since da Vinci Surgical System is a safe and minimally invasive treatment for SPN, it has higher value to the diagnosis and treatment of SPN.