富硒平菇和壶瓶碎米荠中含硒化合物的研究

硒具有多种生理功能,是人体必不可少的微量元素之一。人体不能合成硒,必须从食物中摄取。当前,有机硒因其安全性和高效性已经取代无机硒并成为主流的补硒选择。本文分析了市场上常见的两种富硒农产品中有机硒的含量,并初步研究了其含硒有机化合物的类别及硒代氨基酸的组成。结果表明,富硒壶瓶碎米荠和富硒平菇的有机硒含量分别为(1 607.81±24.66)mg·kg^(-1)和(240.14±8.96)mg·kg^(-1),有机硒占比分别为76.36%±7.81%和99.93%±0.02%。相较于富硒壶瓶碎米荠,富硒平菇含有更多硒多糖和硒蛋白。两个试样均含有丰富的硒代氨基酸,富硒平菇和富硒壶瓶碎米荠的主要硒代氨基酸分别为硒代蛋氨酸和硒代胱氨酸。

工程力学ARCS课程思政教学模式改革与实践

针对传统工程力学课程思政教学中存在的问题,提出了ARCS课程思政教学模式。该模式重点关注学生在接受课程思政教育时的学习动机和亲身感受,通过构建引起注意(A)、思维关联(R)、应用信心(C)和成长满意(S)四个模块,为学生创建关联性强、实践性佳、满意度高的课程思政教学全流程。两个学期的教学实践数据表明,ARCS课程思政教学模式有效降低了学生对课程思政教学的不适感,增强了学生对课程思政教学的共鸣体验,提升了工程力学课程教学质量,凸显了课程思政教学育人价值,工科类课程的课程思政教学提供了新的思路。

Polyphenols extracted from Aronia melanocarpa by combined enzymatic and ultrasonication and their antioxidant potential and antimicrobial activity

The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction conditions were 1%enzyme,1:40 material-to-liquid ratio,55℃,60 min ultrasonication,70%ethanol,and the final extraction amount was 88.634 mg/g,which displayed a 25.15%and 34.08%improvement compared with the single ultrasonication and enzymatic extraction methods,respectively.Significant antibacterial effects of polyphenols were shown against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.Further antioxidation effects were evaluated,and the superoxide anion radical scavenging rate,hydroxyl radical scavenging rate and DPPH free radical scavenging rate reached 45.2%,83.5%and 85.4%,respectively.This combined enzymatic and ultrasonic extraction method exhibited the advantages of high extraction rate,saving solvent consumption and extraction time,but also provided a new method for the development and utilization of natural antimicrobial and antioxidant health products.

神经内镜下治疗基底节区高血压脑出血的效果研究

目的探讨传统开颅手术与神经内镜手术在治疗基底节区高血压脑出血(HICH)患者中的疗效与安全性,为其临床治疗提供一定依据。方法 86例基底节区HICH患者,根据手术方式不同将患者分为神经内镜组(40例)和开颅手术组(46例),开颅手术组采用开颅血肿清除手术治疗,神经内镜组采用神经内镜微创血肿清除手术治疗,对比两组基底节区HICH患者皮肤切口大小、骨窗大小、皮层切口大小、手术时间、术中出血量、血肿清除率、术后并发症、近期与远期疗效和病死率。结果神经内镜组患者的皮肤切口大小、骨窗大小、皮层切口大小、手术时间、术中出血量均明显低于开颅手术组(P <0.01);两组患者血肿清除率差异无统计学意义(P>0.05);神经内镜组患者术后并发症发生率为10.0%,明显低于开颅手术组的28.3%(P <0.05);神经内镜组患者近期疗效良好率为90.0%明显高于开颅手术组的60.9%(P <0.01);神经内镜组患者远期疗效良好率为92.5%明显高于开颅手术组的63.0%(P <0.01);开颅手术组患者死亡3例,病死率6.5%;神经内镜组患者死亡2例,病死率5.0%;两组患者病死率差异无统计学意义(P>0.05)。结论神经内镜手术治疗基底节区HICH可以减小手术创伤,缩短手术时间,降低出血量,提升近期与远期疗效,降低并发症发生率。

Epidemiologic characteristics of oral cancer:single-center analysis of 4097 patients from the Sun Yat-sen University Cancer Center

Background:Oral cancer is a common type of head and neck cancers.Knowing its epidemiologic characteristics is crucial to preventing,diagnosing,and treating this cancer.This study aimed to explore the epidemiologic characteristics of oral cancer in South China.Methods:We retrospectively analyzed data from 4097 oral cancer patients treated at the Sun Yat-sen University Cancer Center between 1960 and 2013.We compared the age of onset,sex ratio,pathologic type,and primary tumor location among three subcultural areas(Guangfu,Hakka,and Chaoshan) and between an economically developed region and a less-developed one in Guangdong.Results:Overall,oral cancer had a male-to-female ratio of approximately 2:1,and this ratio decreased over time.Oral cancer occurred mostly in patients of 45-64 years old(54.5%),and the percentage of older patients gradually increased over time.The most common tumor location was the tongue.Squamous cell carcinoma was the predominant pathologic type.The percentage of blood type O in oral cancer patients was lower than that in the healthy population.The male-to-female ratio in the Chaoshan area was higher than that in the Guangfu and Hakka areas,whereas the age of disease onset in Guangfu was higher than that in Hakka and Chaoshan.The male-to-female ratio was lower and the age of disease onset was higher in the economically developed region than in the less-developed region.Conclusion:The incidence of oral cancer in South China presents typical characteristics to which doctors should pay attention when diagnosing and treating oral cancer patients.

Geomechanical model test for analysis of surrounding rock behaviours in composite strata

Due to the large differences in physico-mechanical pro perties of composite strata,jamming,head sinking and other serious consequences occur frequently during tunnel boring machine(TBM)excavation.To analyse the stability of surrounding rocks in composite strata under the disturbance of TBM excavation,a geomechanical model test was carried out based on the Lanzhou water supply project.The evolution patterns and distribution characteristics of the strain,stress,and tunnel deformation and fracturing were analysed.The results showed that during TBM excavation in the horizontal composite formations(with upper soft and lower hard layers and with upper hard and lower soft layers),a significant difference in response to the surrounding rocks can be observed.As the strength ratio of the surrounding rocks decreases,the ratio of the maximum strain of the hard rock mass to that of the relatively soft rock mass gradually decreases.The radial stress of the relatively soft rock mass is smaller than that of the hard rock mass in both types of composite strata,indicating that the weak rock mass in the composite formation results in the difference in the mechanical behaviours of the surrounding rocks.The displacement field of the surrounding rocks obtained by the digital speckle correlation method(DSCM)and the macro-fracture morphology after tunnel excavation visually reflected the deformation difference of the composite rock mass.Finally,some suggestions and measures were provided for TBM excavation in composite strata,such as advance geological forecasting and effective monitoring of weak rock masses.

METHOD TO CALCULATE STRESS INTENSITY FACTOR OF V-NOTCH IN BI-MATERIALS

Based on Zak＇s stress function, the eigen-equation of stress singularity ofbi-materials with a V-notch was obtained. A new definition of stress intensity factor for a perpendicular interfacial V-notch of bi-material was put forward. The effects of shear modulus and Poisson＇s ratio of the matrix material and attaching material on eigen-values were analyzed. A generalized expression for calculating/（i of the perpendicular V-notch of bi-materials was obtained by means of stress extrapolation. Effects of notch depth, notch angle and Poisson＇s ratio of materials on the singular stress field near the tip of the V-notch were analyzed systematically with numerical simulations. As an example, a finite plate with double edge notches under uniaxial uniform tension was calculated by the method presented and the influence of the notch angle and Poisson＇s ratio on the stress singularity near the tip of notch was obtained.

Bifurcation analysis and exact traveling wave solutions for (2+1)-dimensional generalized modified dispersive water wave equation

We investigate (2+1)-dimensional generalized modified dispersive water wave (GMDWW) equation by utilizing the bifurcation theory of dynamical systems. We give the phase portraits and bifurcation analysis of the plane system corresponding to the GMDWW equation. By using the special orbits in the phase portraits, we analyze the existence of the traveling wave solutions. When some parameter takes special values, we obtain abundant exact kink wave solutions, singular wave solutions, periodic wave solutions, periodic singular wave solutions, and solitary wave solutions for the GMDWW equation.

Adsorptive Stripping Voltammetric Study of the Enhancement of Copper(Ⅱ) by Poly(vinyl alcohol), Starch and Polyallylamine

Adsorptive enhancements of several water-soluble polymers on copper(Ⅱ) were studied by adsorptive stripping voltammetry with a hanging mercury drop electrode. Increases in peak current of cu(Ⅱ) were observed in alkaline carbonate media. The enhancing power of poly(vinyl alcohol), starch and polyallylamine is 15, 4. 1, and 2.5 times, repectively

Determination of Speciation of Magnesium（Ⅱ） in Albumen by Gel Permeation Chromatography

A gel permeation chromatographic method using cross-linked dextran G-50 was employed to determine the speciation of magnesium(Ⅱ) in albumen. It has been found that 0.22% of magnesium(Ⅱ) in albumen combines with proteins and the rest exists as free ions and small-molecular complexes.

Parameter comparison of white matter diffusion tensor imaging （DTI） in rhesus macaques （Macaca mulatta）

In this study, we analyzed diffusion tensor imaging （DTI） results of brain white matter in rhesus macaques （Macaca mulatta） with four different parameter settings and found that the sequence A （b=1000 s/mm^2, spatial resolution=1.25 mm ×1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） and B （b=800 s/mm^2, spatial resolution= 1.25 mm× 1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） could accurately track coarse fibers. The fractional anisotropy （FA） derived from sequence C （b=1000s/mm^2, spatial resolution=0.55 mm×0.55 mm×2.5 mm, direction number=33, NSA=3） was too fuzzy to be used in tracking white matter fibers. By comparison, the high resolution and the FA with high contrast of gray matter and white matter derived from sequence D （b=800 s/mm^2, spatial resolution=1.0 mm×1.0 mm ×1.0 mm, numbers of direction=33, NSA=3） qualified in its application in tracking both thick and thin fibers, making it an optimal DTI setting for rhesus macaques.

Adsorptive Stripping Voltammetric Study of the Enhancement of Copper(Ⅱ) in Phosphate and Carbonate media and in the Presence of Silicate

Adsorptive enhancements of several inorganic salts on copper(II) were studied by adsorptive stripping voltammetry with a hanging mercury drop electrode Increase in peak curren of cu(II) were observed in alkaline phosphate or media owing to adsorption Silicate can also enhance the peak current of Cu(II). The enhancing power phosphate,carbonate, and silicate is 33, 26, and 8.9 times, respectively.

A High Power Carbon/LiM_xO_yHybrid Cathode for Non-Aqueous Li-O₂Battery

Among all the issues that restrict the application of Li-air battery, poor power performances of O2 cathode comes first. In this paper, we establish carbon (Super P)/LiMxOy (LiMn2O4/LiFePO4/LiNi1/3Co1/3Mn1/3O2) hybrid cathode to promote the power output of conventional carbon cathode through continuous Li+-insertion reaction of LiMxOy and Li+ transportation in bulk LiMxOy during the discharging process. Weight and volume specific power performances of the hybrid cathode are much higher than those of traditional Super P carbon cathode. The mechanism of improving power performance of O2 cathode has also been discussed through electrochemical impedance spectroscopy and cyclic voltammetry method in this paper.

Developing a Curriculum System for Engineering Specialties in New Economy

The new economy,featuring new technology,new industry,new business models,and new patterns,has necessitated the development of new requirements for higher engineering education.This paper analyzes the general quality standards of engineering specialists and the way typical universities are responding to new economy worldwide.It also examines how to develop an appropriate curriculum for engineering undergraduates in new economy in terms of curriculum system,organizational teaching,curriculum content,teaching methods,and curriculum evaluation.

Research and Practice of the “Independence + Integration” Moral and Self-cultivation Teaching Method for Online Specialized Courses

In the context of the COVID-19 outbreak,online teaching has spread rapidly.However,the existing research on moral and self-cultivation teaching methods for online courses remains inadequate.This paper proposes an“independence+integration”moral and self-cultivation teaching method for online courses.The method divides the targets of moral and self-cultivation teaching into independent and integrated ones,and fits them both explicitly and implicitly into the online teaching of specialized courses in higher education.When this method was employed to teach engineering mechanics to industrial design students at a college in China,it effectively increased the students’acceptance of online courses as well as their understanding of moral and self-cultivation knowledge and the course itself,and improved the quality of online teaching.The method provides a new way of thinking about online moral and self-cultivation teaching.

Determination of total flavonoids and its antioxidant activity in the exocarp of Aronia melanocarpa

As a kind of berry food rich in flavonoids,the determination method of total flavonoids content of Aronia melanocarpa is of great significance.This paper compares the applicability of NaNO_(2)-Al(NO_(3))_(3)-NaOH colorimetry and AlCl_(3)colorimetry to total flavonoids content of the exocarp of Aronia melanocarpa by Ultraviolet-visible Spectrophotometry.At the same time,we determined hydroxyl radical(OH·-)inhibition rate,superoxide anion radical(O_(2)·-)inhibition rate and 1,1-diphenyl-2-picrylhydrazyl radical free radical(DPPH·)scavenging rate of total flavonoids extracted from Aronia melanocarpa.It is found that AlCl_(3)colorimetry has good repeatability,precision,and accuracy.The method is suitable for the determination of total flavonoids in the exocarp of Aronia melanocarpa.Thus,by the established method the content of total flavonoids in the exocarp of Aronia melanocarpa was determined as high as(36.711±0.034)mg/g.The results of antioxidant activity showed superoxide anion radical scavenging ability,hydroxyl radical scavenging ability and DPPH radical scavenging ability of the total flavonoids extract reached 45.33%,87.87%and 98.05%,respectively,indicating that it had good antioxidant activity.

Optimization of ultrasonic-assisted enzymatic extraction of flavonoids from the fruit oiAronia melanocarpa

As a new resource food,Aronia melanocarpa is rich in flavonoids,which has a broad development prospect.In order to obtain a higher extraction rate of flavonoids,cellulase was used to extract total flavonoids from the fruits of Aronia melanocarpa by ultrasonic-assisted enzymatic extraction(UAEE).The extraction process was optimized by single factor experiment and orthogonal experiment.The optimum conditions were as follows:enzymatic hydrolysis time 2.0 h,enzymatic hydrolysis temperature 37℃,enzyme content 0.5%(by weight of fruit pulp),ethanol concentration 90%,solid-liquid ratio 1:20,enzymatic hydrolysis temperature 37℃,enzymatic hydrolysis temperature 37℃,enzyme content 0.5%(by weight of fruit pulp),ethanol concentration 90%.Ultrasonic extraction time 1,0h,temperature 45℃.Under the above conditions,the extraction yield of flavonoids reached 1.455 mg/g.Compared with ultrasonic-assisted extraction(UAE),the extraction yield was significantly improved.Therefore,ultrasonic-assisted enzymatic hydrolysis is an effective method for the extraction of total flavonoids hom Aronia melanocarpa.

Multimodal Fusion of Brain Imaging Data: Methods and Applications

Neuroimaging data typically include multiple modalities,such as structural or functional magnetic resonance imaging,dif-fusion tensor imaging,and positron emission tomography,which provide multiple views for observing and analyzing the brain.To lever-age the complementary representations of different modalities,multimodal fusion is consequently needed to dig out both inter-modality and intra-modality information.With the exploited rich information,it is becoming popular to combine multiple modality data to ex-plore the structural and functional characteristics of the brain in both health and disease status.In this paper,we first review a wide spectrum of advanced machine learning methodologies for fusing multimodal brain imaging data,broadly categorized into unsupervised and supervised learning strategies.Followed by this,some representative applications are discussed,including how they help to under-stand the brain arealization,how they improve the prediction of behavioral phenotypes and brain aging,and how they accelerate the biomarker exploration of brain diseases.Finally,we discuss some exciting emerging trends and important future directions.Collectively,we intend to offer a comprehensive overview of brain imaging fusion methods and their successful applications,along with the chal-lenges imposed by multi-scale and big data,which arises an urgent demand on developing new models and platforms.

The Neural Mechanism of Knowledge Assembly in the Human Brain Inspires Artificial Intelligence Algorithm

When new information enters the brain,a human's prior knowledge of the world can change rapidly through a process referred to as"knowledge assembly".Recently,Nelli et al.investigated the neural correlates of knowledge assembly in the human brain using functional MRI.Further,inspired by the neural mechanism,the authors developed an artificial neural network algorithm to permit rapid knowledge assembly,improving the flexibility of the system[1].Once again,this research demonstrates that studying how the brain works can lead to better computational algorithms.

EM-fMRI:A Promising Method for Mapping the Brain Functional Connectome

Electrical microstimulation(EM)can be used to locally stimulate the cerebral cortex or subcortical nuclei.Meanwhile,functional magnetic resonance imaging(fMRI)can noninvasively visualize the activity of the whole brain.When EM is combined with fMRI(EM-fMRI),it is possible to measure the changes of the whole-brain neural activity using fMRI while applying electrical stimulation to a specific brain site,and accordingly infer the causal links between the stimulated site and the activated brain areas.