Analysis of Internal Moisture Change of Camphor Seeds during Drying by Low-Field NMR

In this study,low-field nuclear magnetic resonance(LF-NMR)was used to collect the transverse relaxation signals of camphor seeds that had been dried at different temperatures and for different durations.The transverse relaxation time of the hydrogen nucleus was obtained by SIRT(Simultaneous Iterative Reconstruction Technique)inversion,and the correlation between the moisture content on dry basis and the amplitude of NMR signal of camphor seeds sampled at different drying stages was analyzed.The results showed that water existed in three main forms strongly bound water,weakly bound water and free water in camphor seeds.During the drying process,the peak position of strongly bound water remained unchanged,but the peak positions of weakly bound water and free water fluctuated.Drying rate increased with drying temperature increasing.In addition,there was a very significant linear relationship between the total NMR signal amplitude and moisture content on dry basis,and the correlation coefficient reached 0.984 4.

Molecular dynamics study on the dependence of thermal conductivity on size and strain in GaN nanofilms

The thermal conductivity of GaN nanofilm is simulated by using the molecular dynamics(MD)method to explore the influence of the nanofilm thickness and the pre-strain field under different temperatures.It is demonstrated that the thermal conductivity of GaN nanofilm increases with the increase of nanofilm thickness,while decreases with the increase of temperature.Meanwhile,the thermal conductivity of strained GaN nanofilms is weakened with increasing the tensile strain.The film thickness and environment temperature can affect the strain effect on the thermal conductivity of GaN nanofilms.In addition,the analysis of phonon properties of GaN nanofilm shows that the phonon dispersion and density of states of GaN nanofilms can be significantly modified by the film thickness and strain.The results in this work can provide the theoretical supports for regulating the thermal properties of GaN nanofilm through tailoring the geometric size and strain engineering.

基于Nrf2通道研究柚皮素磷脂复合物对氧化损伤ARPE-19细胞的保护作用

目的:研究柚皮素(Nar)及其磷脂复合物(NPC)对叔丁基氢过氧化物(t-BHP)诱导产生的氧化损伤人视网膜色素上皮细胞(ARPE-19细胞)的保护作用及其作用机制。方法:根据文献最佳制作工艺制备NPC。将体外培养的ARPE-19细胞分为溶媒组(用DMSO培养)、模型组(用200μmol/L t-BHP干预)、Nrf2-siRNA组(针对Nrf2基因进行细胞转染)、柚皮素组(200μmol/L柚皮素培养基预处理后加入200μmol/L t-BHP)、NPC组(200μmol/L NPC培养基预处理后加入200μmol/L t-BHP)、Nrf2-siRNA+柚皮素组(200μmol/L柚皮素预处理后Nrf2基因干扰,再加入200μmol/L t-BHP)、Nrf2-siRNA+NPC组(200μmol/L NPC预处理后Nrf2基因干扰,再加入200μmol/L t-BHP)。检测各组细胞内活性氧、丙二醛、超氧化物歧化酶、总抗氧化能力水平,分别采用RT-PCR和Western blot法检测各组细胞内血红素加氧酶-1(HO-1)、醌氧化还原酶-1(NQO-1)、谷氨酸半胱氨酸连接酶(GCL)和核因子E2相关因子2(Nrf2)的表达水平。结果:NPC较柚皮素能明显降低ARPE-19细胞内丙二醛、活性氧的含量,提高细胞内超氧化物歧化酶、总抗氧化能力水平。柚皮素和NPC预保护ARPE-19细胞后,Nrf2、HO-1、NQO-1和GCL mRNA的相对表达量和蛋白表达水平均较模型组和Nrf2-siRNA组升高。柚皮素组与NPC组,Nrf2-siRNA+柚皮素组与Nrf2-siRNA+NPC组细胞内4种基因和蛋白相对表达水平均有差异。Nrf2-siRNA+柚皮素组与Nrf2-siRNA组Nrf2、HO-1、NQO-1蛋白表达无显著差异。Nrf2-siRNA+NPC组与Nrf2-siRNA组4种蛋白表达均有差异,NPC作用明显强于柚皮素。结论:柚皮素磷脂复合物能明显提高细胞内抗氧化能力,降低氧化水平,其通过激活Nrf2/ARE抗氧化应激通路上调Nrf2及其下游抗氧化酶和Ⅱ相解毒酶的表达对氧化损伤的ARPE-19细胞起到更好的保护作用。

Hermite Finite Element Method for a Class of Viscoelastic Beam Vibration Problem

Beam equation can describe the deformation of beams and reflect various bending problems and it has been widely used in large engineering projects, bridge construction, aerospace and other fields. It has important engineering practice value and scientific significance for the design of numerical schemes. In this paper, a scheme for vibration equation of viscoelastic beam is developed by using the Hermite finite element. Based on an elliptic projection, the errors of semi-discrete scheme and fully discrete scheme are analyzed respectively, and the optimal L2-norm error estimates are obtained. Finally, a numerical example is given to verify the theoretical predictions and the validity of the scheme.

后扶贫时代教育扶贫应处理好的几对关系

全面脱贫时间节点的到来为教育扶贫开启了新的思维起点,向教育扶贫提出了过程性挑战。基于后扶贫时代贫困现象的主要特征,教育扶贫质量的可持续提升有赖于处理好教育发展与教育扶贫、扶智与扶志、农村教育贫困与城市教育贫困、扶贫主体与贫困主体、教育扶贫的国际经验与本土实践等关系。后扶贫时代的教育扶贫应诉诸多维关系视域的系统化行动,在扶贫实践中需进一步凸显教育发展的功能建设、精神扶贫的价值指向,关注特殊贫困人群的主体特征、倾听教育贫困者的主体诉求,探索国际教育扶贫经验的在地化实践,推动实现我国教育扶贫经验的国际社会贡献力。

考虑出口宽度因素的多出口应急疏散模型研究

本文选择社会力模型作为行人疏散理论,并在此基础上进行仿真实验,研究单出口环境中出口宽度与疏散时间的关系;为了进一步研究多出口环境中宽度变化对疏散的影响,以社会力模型为基础,构建了考虑距离因素、宽度因素的行人疏散模型;仿真结果表明,出口宽度的变化极大影响整体疏散效率;单出口环境中,宽度大小与疏散时间整体呈反比,当宽度达到一定值时,疏散时间趋于稳定;多出口环境中,仅考虑距离因素时,出口宽度差值的绝对值与疏散时间呈正比,添加宽度因素考虑后,提高了整体疏散效率,疏散时间在一定范围内波动。

纤维型黏土在日化领域的应用研究进展

纤维型黏土(包含海泡石与坡缕石/凹凸棒石)是一类晶体结构呈纤维状、含水富镁铝硅酸盐的天然一维黏土矿物,其特殊的微观形貌(棒状、纤维状或纤维集合体)和纳米级孔道赋予了这类黏土矿物优异的离子交换能力、吸附性能、流变调节性和载体功能。近年来,纤维型黏土在个人护理品、洗涤用品等日用消费品中的应用增长迅速。该文以纤维型黏土的流变调节、防晒修饰、抑菌消炎、吸附与控释四种应用特性为主线,综述了这类天然黏土矿物在日用化学工业领域的应用特性、相关机理及毒理学研究进展,分析了纤维型黏土在日化领域应用面临的问题与挑战,并对其未来的发展趋势进行了展望,为我国科研人员充分利用优势矿物资源,进一步开发出高技术含量的日化产品提供参考。

Serum and cerebrospinal fluid tau protein level as biomarkers for evaluating acute spinal cord injury severity and motor function outcome

Tau protein, a microtubule-associated protein, has a high specific expression in neurons and axons. Because traumatic spinal cord injury mainly affects neurons and axons, we speculated that tau protein may be a promising biomarker to reflect the degree of spinal cord injury and prognosis of motor function. In this study, 160 female Sprague-Dawley rats were randomly divided into a sham group, and mild, moderate, and severe spinal cord injury groups. A laminectomy was performed at the T8 level to expose the spinal cord in all groups. A contusion lesion was made with the NYU-MASCIS impactor by dropping a 10 g rod from heights of 12.5 mm(mild), 25 mm(moderate) and 50 mm(severe) upon the exposed dorsal surface of the spinal cord. Tau protein levels were measured in serum and cerebrospinal fluid samples at 1, 6, 12, 24 hours, 3, 7, 14 and 28 days after operation. Locomotor function of all rats was assessed using the Basso, Beattie and Bresnahan locomotor rating scale. Tau protein concentration in the three spinal cord injury groups(both in serum and cerebrospinal fluid) rapidly increased and peaked at 12 hours after spinal cord injury. Statistically significant positive linear correlations were found between tau protein level and spinal cord injury severity in the three spinal cord injury groups, and between the tau protein level and Basso, Beattie, and Bresnahan locomotor rating scale scores. The tau protein level at 12 hours in the three spinal cord injury groups was negatively correlated with Basso, Beattie, and Bresnahan locomotor rating scale scores at 28 days(serum: r =-0.94; cerebrospinal fluid: r =-0.95). Our data suggest that tau protein levels in serum and cerebrospinal fluid might be a promising biomarker for predicting the severity and functional outcome of traumatic spinal cord injury.

ZD 7288,an HCN channel blocker,attenuates chronic visceral pain in irritable bowel syndrome-like rats

AIM:To investigate the effects of ZD 7288,a hyperpolarization-activated cyclic nucleotide-gated(HCN)channel blocker,on rats with chronic visceral pain.METHODS:Rats with visceral hypersensitivity were generated using neonatal colon irritation during postnatal days 8-15 as described previously.Visceral hypersensitivity was evaluated using electromyographic(EMG)responses of abdominal external oblique muscles to 20-80 mmHg colorectal distentions(CRD).Abdominal withdrawal reflex(AWR)scores and pain thresholds were also detected in adult rats.Different doses of ZD7288(25,50,and 100 nmol/L)were intrathecally administered in rats to study the role of spinal HCN channel in chronic visceral hypersensitivity.RESULTS:EMG responses to 20-80 mmHg CRD and AWR scores under 20-60 mmHg CRD significantly increased in rats with visceral hypersensitivity compared to control rats(P<0.05).The pain threshold in rats with visceral hypersensitivity significantly decreased compared to control rats(P<0.05).Treatment with50-100 nmol/L ZD 7288 significantly inhibited EMG responses(16%-62%,80-20 mmHg CRD,P<0.05)and AWR scores(24%-37%,40-20 mmHg CRD,P<0.05;12%-61%,80-20 mmHg CRD,P<0.05,respectively),and significantly increased pain thresholds(32%-77%,P<0.05).CONCLUSION:Spinal HCN channels may play an important role in chronic visceral hypersensitivity.

Energy Consumption Prediction of a CNC Machining Process With Incomplete Data

Energy consumption prediction of a CNC machining process is important for energy efficiency optimization strategies.To improve the generalization abilities,more and more parameters are acquired for energy prediction modeling.While the data collected from workshops may be incomplete because of misoperation,unstable network connections,and frequent transfers,etc.This work proposes a framework for energy modeling based on incomplete data to address this issue.First,some necessary preliminary operations are used for incomplete data sets.Then,missing values are estimated to generate a new complete data set based on generative adversarial imputation nets(GAIN).Next,the gene expression programming(GEP)algorithm is utilized to train the energy model based on the generated data sets.Finally,we test the predictive accuracy of the obtained model.Computational experiments are designed to investigate the performance of the proposed framework with different rates of missing data.Experimental results demonstrate that even when the missing data rate increases to 30%,the proposed framework can still make efficient predictions,with the corresponding RMSE and MAE 0.903 k J and 0.739 k J,respectively.

Stable and metastable phase equilibria in binary Mg-Gd system: A comprehensive understanding aided by CALPHAD modeling

In this paper,a comprehensive understanding of stable and metastable phase equilibria in binary Mg-Gd system was conducted with an aid of the CALculation of PHAse Diagram(CALPHAD)modeling.Firstly,thermodynamic descriptions of all the stable phases in the Mg-Gd system were re-assessed by considering all the experimental data in the literature.The discrepancy between the phase equilibria and thermochemical properties existing in the previous assessments was eliminated,and the better agreement with the experimental data was achieved in the present assessment.Secondly,the Gibbs energies for metastable β"-Mg3Gd and β"-Mg7Gd were constructed based on the first-principles and CALPHAD computed results as well as their correlation,and then incorporated into the CALPHAD descriptions.The model-predicted solvuses of(Mg)in equilibrium with the metastable β"-Mg7Gd and β'-Mg7Gd compounds showed very good agreement with the limited experimental data.Finally,the presently obtained thermodynamic descriptions of both stable and metastable phases in the binary Mg-Gd system were further validated by realizing the quantitative Scheil-Gulliver solidification simulations of 5 as-cast Mg-Gd alloys,and the successful prediction of the precipitation sequences in Mg-15Gd and Mg-12Gd alloys during the aging process.

Analysis of influence of observation operator on sequential data assimilation through soil temperature simulation with common land model

An observation operator is a bridge linking the system state vector and observations in a data assimilation system. Despite its importance, the degree to which an observation operator influences the performance of data assimilation methods is still poorly understood. This study aimed to analyze the influences of linear and nonlinear observation operators on the sequential data assimilation through soil temperature simulation using the unscented particle filter(UPF) and the common land model. The linear observation operator between unprocessed simulations and observations was first established. To improve the correlation between simulations and observations, both were processed based on a series of equations. This processing essentially resulted in a nonlinear observation operator. The linear and nonlinear observation operators were then used along with the UPF in three assimilation experiments: an hourly in situ soil surface temperature assimilation, a daily in situ soil surface temperature assimilation, and a moderate resolution imaging spectroradiometer(MODIS) land surface temperature(LST) assimilation. The results show that the filter improved the soil temperature simulation significantly with the linear and nonlinear observation operators. The nonlinear observation operator improved the UPF's performance more significantly for the hourly and daily in situ observation assimilations than the linear observation operator did, while the situation was opposite for the MODIS LST assimilation. Because of the high assimilation frequency and data quality, the simulation accuracy was significantly improved in all soil layers for hourly in situ soil surface temperature assimilation, while the significant improvements of the simulation accuracy were limited to the lower soil layers for the assimilation experiments with low assimilation frequency or low data quality.

ROR1在肺腺癌组织中的表达与气腔播散相关性

目的研究受体酪氨酸激酶样孤儿受体1(receptor tyrosine kinase-like orphan rectetpor 1,ROR1)在不同病理亚型肺腺癌组织中的表达与气腔播散(spread through air space,STAS)发生的关系。方法收集昆明医科大学第一附属医院病理科2017年6月至2022年1月,肺腺癌组织蜡块标本618例,采用HE染色切片判断病理亚型与病理特征,记数STAS数量并分级,免疫组化染色,半定量判读ROR1表达水平,统计分析ROR1表达与STAS数量及与病理亚型的关系。结果ROR1在微乳头型与实体型肺腺癌(低分化)中的表达高于其它亚型肺腺癌,差异有统计学意义(P<0.001);ROR1在低STAS、高STAS组中表达率分别为88.0%、94.1%,高于无STAS组且差异有统计学意义(P<0.001)。结论ROR1高表达于低分化肺腺癌并提示更高的STAS发生率。ROR1有望成为新的肺腺癌诊断生物标志物用于指导临床治疗及辅助预后判断,并可能成为STAS阳性肺腺癌的潜在治疗靶点。

Isolation of a novel characterized Issatchenkia terricola from red raspberry fruits on the degradation of citric acid and enrichment of flavonoid and volatile profiles in fermented red raspberry juice

High content of citric acid in red raspberry juice leads to poor sensory experience. This study developed a feasible method to degrade citric acid in red raspberry juice using a novel characterized Issatchenkia terricola WJL-G4 isolated from red raspberry fruits. I. terricola WJL-G4 exhibited a potent capability of reducing the citric acid contents from(22.8 ± 0.08) g/L to(6.2 ± 0.02) g/L within 36 h fermentation, then completely depleted after 48 h. Furthermore, the contents of phenolic compound, including neochlorogenic acid, p-coumaric acid, raspberry ketone, and rutin significantly increased after 36 h fermentation. Fermentation increased total flavonoid contents in red raspberry juice, compared to that in control group. Volatile profiles exhibited to be enriched after fermentation, which contributed to the improvement of the juice taste. Our findings showed that I. terricola WJL-G4 can be applied in deacidification, enrichment of flavonoid compounds and volatile profiles in fermented red raspberry juice..

Acanthopanax senticosus aqueous extract protects PC12 cells against hypoxic injury

Acanthopanax senticosus aqueous extract, at 10, 5 and 2.5 μg/mL, lessened hypoxia-induced PC12 cell injury. Pretreatment with the extract upregulated Bcl-2 expression, downregulated Bax expression, elevated superoxide dismutase activity, diminished malondialdehyde content, relieved Ca2＋ overloading, and suppressed apoptosis of PC12 cells. These effects were most pronounced at 10 μg/mL. These results suggest that Acanthopanax senticosus aqueous extract protects PC12 cells from hypoxia-induced injury in a dose-dependent manner.

Thermodynamic descriptions of quaternary Mg-Al-Zn-Bi system supported by experiments and their application in descriptions of solidification behavior in Bi-additional AZ casting alloys

16 Mg-Al-Zn-Bi quaternary alloys were utilized to measure the phase equilibria and transformation temperatures in the Mg-rich Mg-Al-Zn-Bi quaternary system by means of the X-ray diffraction,electron probe micro-analysis and differential scanning calorimetry techniques.The isothermal section at 400℃and three vertical sections along Mg-8 wt%Al-0.75 wt%Zn-vBi,Mg-3.4 wt%Al-0.5 wt%Zn-ABi and Mg-6.9 wt%Al-2.3 wt%Zn-xBi in the Mg-Al-Zn-Bi quaternary system were constructed.Based on the literature data,the ternary Mg-Al-Bi and Mg-Bi-Zn systems were re-assessed using the CALculaiton of PHAse Diagram(CALPHAD)approach.The calculated phase equilibria agree well with the measured data.By directly extrapolating the constituent sub-ternary systems,the thermodynamic database for the Mg-Al-Zn-Bi quaternary system was developed.The remarkable consistency between the predicted phase equilibria and the presently measured data in Mg-Al-Zn-Bi quaternary system further demonstrated the accuracy and reliability of the established thermodynamic database.After that,by using the newly developed thermodynamic database,the growth restrict factors and the solidification curves in Bi-containing AZ series magnesium alloys were calculated and analyzed.It was confirmed that the grain size of AZ alloys can be refined with the addition of Bi,and the comp on ent Al had larger grain refinement effect than Bi.Besides,the amount of Bi had also no ticeable effect on the solidification sequence of the AZ alloys.

阴道消除量联合放化疗对巨块型ⅢB期宫颈鳞癌的疗效分析

目的:观察阴道消除量在巨块型ⅢB期宫颈鳞癌治疗中的有效性及安全性。方法:回顾性分析2016年1月至2017年6月49例于重庆大学附属肿瘤医院收治的巨块型ⅢB期宫颈鳞癌患者的临床资料,行阴道消除量+同步放化疗,采用Kaplan-Meier法进行生存分析,采用Cox比例风险回归模型进行预后多因素分析。结果:中位随访时间为36.0个月,完全缓解率为83.7%(41/49),局部复发率为4.1%(2/49),远处转移率为34.7%(17/49)。3年总生存(overall survival,OS)率为76.6%、无病生存(disease free survival,DFS)率为26.7%、无远处转移生存(distant metastais free survival,DMFS)率为26.7%、局部控制率(local control rate,LCR)为77.8%。出现的3~4级急性期不良反应中骨髓抑制占40.82%(20/49)、腹泻占20.41%(10/49)、尿频占6.12%(3/49);出现的3~4级晚期不良反应中放射直肠炎占20.41%(10/49)、膀胱炎占8.16%(4/49)。多因素分析采用Cox比例风险回归模型显示放疗时程影响OS、LCR(P<0.05),A点EQD2剂量影响DMFS、LCR(P<0.05),同步放化疗后鳞状细胞癌相关抗原SCC未转阴者复发率为61%(11/18)。结论:巨块型ⅢB期宫颈鳞癌患者在阴道消除量联合放化疗中生存获益,但直肠、膀胱的不良反应增加,建议个体化治疗。放疗时程是宫颈癌预后的独立因素,SCC可用于宫颈癌随访及监测复发。

Research on representative brand and operation mode of second-hand clothing in Europe

In order to study the current situation and operation mode of second-hand clothing brand in Europe,this paper makes a field investigation on the second-hand clothing shops in European countries.Through classification of the inspected shops,five representative brands with certain popularity and influence and different operation modes in Europe are selected out from high-grade antique boutiques,non-profit charity organizations,professional retailers and middle-grade consignment shops in the second-hand clothing market.This paper analyzes and discusses the development history of stores,the source of goods,the form of stores,and the operation mode,so as to provide a reference for the development and standardization of the second-hand clothing market in China.

IN VIVO NEAR-INFRAREDFLUORESCENCEIMAGING OF HUMANCOLONADENOCARCINOMABY SPECIFIC IMMUNOTARGETINGOFA TUMOR-ASSOCIATEDMUCIN

Background and Aims: Accurate endoscopic detection of premalignant lesions and earlycancers in the colon is essential for cure, since prognosis is closely related to lesion size andstage. Although it has great clinical potential, autofluorescence endoscopy has limited tumorto-normal tissue image contrast for detecting small preneoplastic lesions. We have developed amolecularly specific, near-infrared fluorescent monoclonal antibody (CC49) bioconjugate whichtargets tumor-associated glycoprotein 72 (TAG72), as a contrast agent to improve fluorescencebased endoscopy of colon cancer. Methods: The fluorescent anti-TAG72 conjugate was evaluated in vitro and in vivo in athymic nude mice bearing human colon adenocarcinoma (LS174T)subcutaneous tumors. Autofluorescence, a fluorescent but irrelevant antibody and the free fluorescent dye served as controls. Fluorescent agents were injected intravenously, and in vivowhole body fluorescence imaging was performed at various time points to determine pharmacokinetics, followed by ex vivo tissue analysis by confocal fluorescence microscopy and histology Results: Fluorescence microscopy and histology confirmed specific LS174T cell membrane targeting of labeled CC49 in vitro and ex vivo. In vivo fluorescence imaging demonstrated significant tumor-to-normal tissue contrast enhancement with labeled-CC49 at three hours postinjection, with maximum contrast after 48 h. Accumulation of tumor fluorescence demonstratedthat modification of CC49 antibodies did not alter their specific tumor-localizing properties, andwas antibody-dependent since controls did not produce detectable tumor fluorescence. Conclusions: These results show proof-of-principle that our near-infrared fluorescent-antibody probetargeting a tumor-associated mucin detects colonic tumors at the molecular level in real time,and offer a basis for future improvement of image contrast during clinical fluorescence endoscopy.

Characteristics and influencing factors of frontal upwelling in the Yellow Sea in summer

Frontal upwelling is an important phenomenon in summer in the Yellow Sea(YS)and plays an essential role in the distribution of nutrients and biological species.In this paper,a three-dimensional hydrodynamic model is applied to investigate the characteristics and influencing factors of frontal upwelling in the YS.The results show that the strength and distribution of frontal upwelling are largely dependent on the topography and bottom temperature fronts.The frontal upwelling in the YS is stronger and narrower near the eastern coast than near the western coast due to the steeper shelf slope.Moreover,external forcings,such as the meridional wind speed and air temperature in summer and the air temperature in the preceding winter and spring,have certain influences on the strength of frontal upwelling.An increase in air temperature in the previous winter and spring weakens the frontal upwelling in summer;in contrast,an increase in air temperature in summer strengthens the frontal upwelling.When the southerly wind in summer increases,the upwelling intensifies in the western YS and weakens in the eastern YS.The air temperature influences the strength of upwelling by changing the baroclinicity in the frontal region.Furthermore,the meridional wind speed in summer affects frontal upwelling via Ekman pumping.