OH+HCl→Cl+H_(2)O反应中的反应物转动激发效应

本文在最近构建的F12a势能面上,对OH+HCl→Cl+H_(2)O的一系列反应物转动激发态进行了势能平均的五维含时波包计算,得到了初始态选择的反应几率和速率常数。研究发现,除了很低碰撞能量,单独激发反应物HCl到j_(1)=2或者OH到j_(2)=1得到了总反应几率的最大值.在低能区域,随着OH转动激发的增加,反应几率的共振增强迅速减小,导致250K以下的速率常数迅速下降HCl和OH同时转动激发的速率常数不是单独激发结果的简单叠加。最后,通过对(5,5)态以下初始转动态的速率常数进行玻尔兹曼平均,得到了反应的热速率常数,与实验结果基本吻合。

从医学生视角看眼科见习期间裂隙灯训练的必要性

目的:基于医学生视角评估裂隙灯生物显微镜(以下简称“裂隙灯”)训练的必要性,对眼科见习期间的医学生裂隙灯训练达成共识。方法:在中山大学117名2017级临床医学专业学生中,开展见习前后对照研究。所有医学生在眼科见习期间均接受裂隙灯训练。使用自行设计的问卷调查,评估学生对裂隙灯教学的个人认知、个人需求与建议,并对眼科见习前后学生在这些方面的得分进行比较。此外,通过眼科见习后的学生主观评价来评估裂隙灯训练的效果。每个条目评分采用Likert 5级评分法。采用IBM SPSS软件(版本20.0;SPSS Inc.,Chicago,IL,USA)进行统计分析。结果:共有116名(99.1%)医学生完成了调查。见习前的平均得分为19.99±3.03分,显示学生对裂隙灯用途的认知水平高;见习后的得分显著增加至22.97±2.37分(P<0.001)。对于个人需求的平均得分,见习后高于见习前(24.62±3.15 vs 23.60±2.36,P=0.009)。此外,86.2%的学生见习后认为裂隙灯实操训练有助于显著改善见习质量。大于四分之三的被调查学生倾向于增加裂隙灯训练时间(见习前后分别为76.7%和77.6%)。结论:在眼科见习中,医学生更偏好于裂隙灯训练实操;鉴于对改善见习质量的潜在作用,应在眼科见习中推荐该训练。

化妆品原料标准现状及缺失分析

化妆品的质量很大程度上取决于所用原料,通过分析和整理化妆品原料标准,发现目前国家和行业化妆品原料标准主要包括《化妆品安全技术规范》限用、准用物质,可能含有害杂质的原料、基础原料和功效成分这几类,团体标准更侧重于制订基础成分的原料标准和植物提取物的原料标准。有不少常用原料虽然没有化妆品专用的标准,但是可以参考、借鉴其他行业的标准。总体而言,有质量标准的原料仅占《已使用化妆品原料目录》中的小部分,热门的纳米成分标准缺失,植物提取物原料标准中的特征性指标设定也有所欠缺。缺乏统一的化妆品原料标准给企业的质量控制、政府部门的监督带来了不小的困难,今后建议加强可能含有害杂质的化妆品原料、功效性成分、纳米成分和植物提取物的原料标准制订,完善化妆品原料标准化体系。

抗紫外线高压钢丝缠绕增强聚乙烯复合管的制备及性能

针对目前钢丝缠绕增强聚乙烯复合管(简称钢丝管)无法露天使用及最大承压为3.5 MPa而不能满足高压领域应用的难题,制备了抗紫外线聚乙烯专用料,研制了最大承压7.0 MPa抗紫外线钢丝管。通过力平衡法设计了增强钢丝的配置,利用20℃和60℃静液压及爆破压力测试验证了钢丝管的承压能力,采用紫外光老化试验测试了抗紫外线聚乙烯专用料的抗紫外光效果。结果表明,通过4层钢丝缠绕增强结构使用400根直径1.2 mm钢丝,制备了高压钢丝管;钢丝管通过了20℃,14 MPa,1 h及60℃,8.4 MPa,165 h静液压测试,爆破压力达到21.9 MPa,说明钢丝管的承压达到设计压力7.0 MPa的要求;抗紫外线聚乙烯专用料经过336 h的紫外光老化试验,力学性能保持率大于80%,表明抗紫外线聚乙烯专用料具有良好的抗紫外线效果。

Dysfunction of the neurovascular unit in brain aging

An emerging concept termed the neurovascular unit(NVU)underlines neurovascular coupling.It has been reported that NVU impairment can result in neurodegenerative diseases,such as Alzheimer's disease and Parkinson's disease.Aging is a complex and irreversible process caused by programmed and damage-related factors.Loss of biological functions and increased susceptibility to additional neurodegenerative diseases are major characteristics of aging.In this review,we describe the basics of the NVU and discuss the effect of aging on NVU basics.Furthermore,we summarize the mechanisms that increase NVU susceptibility to neurodegenerative diseases,such as Alzheimer's disease and Parkinson's disease.Finally,we discuss new treatments for neurodegenerative diseases and methods of maintaining an intact NVU that may delay or diminish aging.

福州市闽江公园中不同绿量的群落热舒适度

为了解不同绿量植物群落调节热舒适度的效果,对福州市闽江公园(南园)的20个乔灌草群落样方进行绿量与生理等效温度PET值的测算,并对绿量与PET值进行相关性分析。结果表明:乔灌草群落中,每百平方米绿地总绿量小于800 m3时,总绿量越大,群落调节热舒适度的效果越好,每百平方米绿地总绿大于800 m3时,绿量变化不影响热舒适度。乔木绿量占比达0.9时,群落改善热舒适度的效果最佳。

Effects of Remifentanil Pretreatment on Inflammatory Response in Rats with Acute Cerebral Ischemia Injury

[Objectives]This study was conducted to investigate the effects of remifentanil pretreatment on inflammatory factors in rats with acute cerebral ischemia.[Methods]Sixty SD rats were randomly divided into the normal control group,sham operation group,ischemic brain injury group,and remifentanil pretreatment group.Except the normal control group,each group was divided into three subgroups(six in each group)according to the sampling time points of 6,12 and 24 h after execution.After modeling,the rats were scored for neurological deficit,and observed for pathological changes of neurons in the brain tissue by HE staining and the brain infarct volume by TTC staining,and the expression levels of TNF-α,IL-6 and IL-8 were detected by RT-PCR.[Results]HE staining:No significant changes were observed in the pathological morphology of the brain tissue in the blank group and sham operation group;and the neuronal structure of rats in the acute cerebral ischemia group was obviously damaged,and the neuronal damage in the remifentanil pretreatment group was less than that in the acute cerebral ischemia group at each time point.TTC staining:The gray brain infarct area in the remifentanil pretreatment group was significantly smaller than that in the cerebral ischemia group(P<0.05).RT-PCR detection results:The expression levels of TNF-α,IL-6 and IL-8 in the blank group and sham surgery group did not show significant changes at different times(P>0.05);and compared with the cerebral ischemia group,the expression levels of TNF-α,IL-6,and IL-8 in the remifentanil pretreatment group were significantly reduced at all time points(P<0.05).[Conclusions]Remifentanil pretreatment could protect the brain by reducing the expression of inflammatory factors after cerebral ischemia injury.

Pilot HI survey of Planck Galactic Cold Clumps with FAST

We present a pilot HI survey of 17 Planck Galactic Cold Clumps(PGCCs)with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).HI Narrow Self-Absorption(HINSA)is an effective method to detect cold HI being mixed with molecular hydrogen H2 and improves our understanding of the atomic to molecular transition in the interstellar medium.HINSA was found in 58%PGCCs that we observed.The column density of HINSA was found to have an intermediate correlation with that of 13CO,following log(N(HINSA))=(0.52±0.26)log(N13CO)+(10±4.1).HI abundance relative to total hydrogen[HI]/[H]has an average value of 4.4×10-3,which is about 2.8 times of the average value of previous HINSA surveys toward molecular clouds.For clouds with total column density NH>5×1020 cm-2,an inverse correlation between HINSA abundance and total hydrogen column density is found,confirming the depletion of cold HI gas during molecular gas formation in more massive clouds.Nonthermal line width of 13CO is about 0-0.5 kms-1 larger than that of HINSA.One possible explanation of narrower non-thermal width of HINSA is that HINSA region is smaller than that of 13CO.Based on an analytic model of H2 formation and H2 dissociation by cosmic ray,we found the cloud ages to be within 106.7-107.0 yr for five sources.

木耳菌菌糠在改良园林绿化用土中的作用

木耳的菌糠中含有大量的人体所需成分,比如蛋白质、氨基酸和维生素等。另外,木耳菌糠中还含有氮、磷、钾等能用于施肥的元素。所以木耳菌糠具有非常重要的再利用价值。菌糠可以作为有机肥料,对植物生长的土壤进行有效的改良。而木耳在其生产的过程中往往能够产生大量的菌糠,这些菌糠需要进行及时妥善的处理,不然会对木耳菌的生产与销售产生一定的影响。木耳菌的菌糠数量过多的话,很容易导致环境受到污染,甚至于导致大批量的病虫害蔓延,从而对木耳菌的质量产生严重的影响。对木耳菌菌糠在改良园林绿化用土中的作用进行研究。

A Scheme of Dynamic Voltage Restorer to Improve Power Quality in Large Scale Industrial Enterprises

Loads in large scale industrial enterprises are always various and complex, causing insecure power quality. Meanwhile, some sensitive loads or precise instruments demand for high power quality. When voltage flicker or harmonics occurs, dynamic voltage restorer (DVR) can be used to stabilize the load-side voltage, which is a good manner of improving power quality. The paper explains the load demand in large scale industrial enterprises, analyzes several common voltage compensation scheme of DVR, and comes up with another voltage compensation scheme of DVR applied for double power supply with double load. A Simulink model according to the new scheme is also built in MATLAB/Simulink to test its performance. Simulation results show that the proposed scheme can guarantee the load-side voltage stability, which is an effective scheme for managing power quality.

地诺单抗治疗骨巨细胞瘤的研究进展

骨巨细胞瘤是一种以溶骨性破坏为特征的侵袭性肿瘤,手术治疗后复发率高,少数会出现肉瘤样恶变及转移。近年来,针对特异性靶向核因子κB受体活化因子配体(receptor activator of nuclear factor kappa B ligand,RANKL)的地诺单抗治疗高级别、不可切除和转移性骨巨细胞瘤疗效显著,能够降低外科分期,增加手术切除几率,减少术后功能丧失,控制肿瘤进展;同时,用药后影像及病理学出现特征性改变,对临床诊断及手术治疗提出新的问题。最后,地诺单抗在用药时间、安全性方面尚有部分争议,有待进一步临床试验证实。

Quercetin protects against diabetic retinopathy in rats by inducing heme oxygenase-1 expression

Quercetin is a widely-occurring flavonoid that protects against cancer, and improves memory and cardiovascular functions.However, whether quercetin exhibits therapeutic effects in diabetic retinopathy remains unclear.In this study, we established a rat model of streptozocininduced diabetic retinopathy.Seventy-two hours later, the rats were intraperitoneally administered 150 mg/kg quercetin for 16 successive weeks.Quercetin markedly increased the thickness of the retinal cell layer, increased the number of ganglion cells, and decreased the overexpression of the pro-inflammatory factors interleukin-1β, interleukin-18, interleukin-6 and tumor necrosis factor-α in the retinal tissue as well as the overexpression of high mobility group box-1 and the overactivation of the NLRP3 inflammasome.Furthermore, quercetin inhibited the overexpression of TLR4 and NF-κBp65, reduced the expression of the pro-angiogenic vascular endothelial growth factor and soluble intercellular adhesion molecule-1, and upregulated the neurotrophins brain-derived neurotrophic factor and nerve growth factor.Intraperitoneal injection of the heme oxygenase-1 inhibitor zinc protoporphyrin blocked the protective effect of quercetin.These findings suggest that quercetin exerts therapeutic effects in diabetic retinopathy possibly by inducing heme oxygenase-1 expression.This study was approved by the Animal Ethics Committee of China Medical University, China(approval No.2016 PS229K) on April 8, 2016.

Scutellarin protects oxygen/glucose-deprived astrocytes and reduces focal cerebral ischemic injury

Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxida- tive effects and has been used to treat cardiovascular and cerebrovascular diseases in China. However, the mechanisms by which scutellarin mediates neuroprotection in cerebral ischemia remain unclear. The interaction between scutellarin and nicotinamide adenine dinucleotide phosphate oxidase 2 （NOX2） was assessed by molecular docking study, which showed that scutellarin selectively binds to NOX2 with high affinity. Cultures of primary astrocytes isolated from the cerebral cortex of neonatal Sprague-Dawley rats were pretreated with 2, 10 or 50 μM scutellarin for 30 minutes. The astrocytes were then subjected to oxygen/glucose deprivation by incubation for 2 hours in glucose-free Dulbecco＇s modified Eagle＇s medium in a 95% N2/5% CO2 incubator, followed by simulated reperfusion for 22 hours. Cell viability was assessed by cell counting kit-8 assay. Expression levels of NOX2, connexin 43 and caspase-3 were assessed by western blot assay. Reactive oxygen species were measured spectrophotometrically. Pretreatment with 10 or 50 μM scutellarin substantially increased viability, reduced the expression of NOX2 and caspase-3, increased the expression of connexin 43, and diminished the levels of reactive oxygen, species in astrocytes subjected to ischemia-＇reperfusion. We also assessed the effects of scutellarin in vivo in the rat transient middle cerebral artery occlusion model of cerebral ischemia-reperfusion injury. Rats were given intraperitoneal injection of 100 mg/kg scutellarin 2 hours before surgery. The Bederson scale was used to assess neurological deficit, and 2,3,5-triphenyltetrazolium chloride staining was used to measure infarct size. Western blot assay was used to assess expression of NOX2 and connexin 43 in brain tissue. Enzyme-linked immunosorbent assay was used to detect 8-hydroxydeoxyguanosine （8-OHdG）, 4-hydroxy-2-nonenal （4-HNE） and 3-nitrotyrosin （3-NT） in brain tissue. Immunofluorescence double staining was used to determine the co-expression of caspase-3 and NeuN. Pretreatment with scutellarin im- proved the neurological function of rats with focal cerebral ischemia, reduced infarct size, diminished the expression of NOX2, reduced levels of 8-OHdG, 4-HNE and 3-NT, and reduced the number of cells co-expressing caspase-3 and NeuN in the injured brain tissue. Furthermore, we examined the effect of the NOX2 inhibitor apocynin. Apocynin substantially increased connexin 43 expression in vivo and in vitro. Collectively, our findings suggest that scutellarin protects against ischemic injury in vitro and in vivo by downregulating NOX2, upregulating connexin 43, decreasing oxidative damage, and reducing apoptotic cell death.

江苏省珍稀濒危植物分布格局分析

在全球气候变化剧烈的背景下,珍稀濒危植物面临的严峻生存状况将进一步影响生物多样性的可持续发展.收集统计了江苏省24科37属43种野生珍稀濒危植物的相关信息,利用ArcGIS将植物分布格局进行空间可视化显示,结合各区(市)地理环境与人口经济等情况进行数据分析,结果显示:江苏省珍稀濒危植物大多分布范围较狭窄,呈小数量零星分布,其中特有种包含金钱松(Pseudolarix amabilis)和秤锤树(Sinojackia xylocarpa)等8种.省内珍稀濒危植物属的地理区系成分较为多样,具有热带和温带的过渡特性.生活型具有典型地带性植被特征,以落叶高位芽植物为主.省内珍稀濒危植物集中分布于西南部丘陵地带,植物狭窄的适生生境、微生境的构成和人类经济活动对自然的影响共同促成了江苏省珍稀濒危植物的分布格局.

Preface:Planning the scientific applications of the Five-hundred-meter Aperture Spherical radio Telescope

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) is by far the largest telescope of any kind ever built. FAST produced its first light in September 2016 and it is now under commissioning, with normal operation to commence in late 2019. During testing and early science operation, FAST has started making astronomical discoveries, particularly pulsars of various kinds, including millisecond pulsars, binaries, gamma-ray pulsars, etc. The papers in this mini-volume propose ambitious observational projects to advance our knowledge of astronomy, astrophysics and fundamental physics in many ways.Although it may take FAST many years to achieve all the goals explained in these papers, taken together they define a powerful strategic vision for the next decade.

支气管镜肺泡灌洗术早期介入治疗对艾滋病合并重症肺炎的作用

目的探讨支气管镜肺泡灌洗术的早期介入治疗对艾滋病并发重症肺炎患者的作用。方法选取2018年1月至2021年6月在昆明市第三人民医院重症医学科住院且需有创机械通气支持的成人艾滋病并发重症肺炎患者(44例),分为观察组和对照组,每组分别为22例。观察组除采取常规治疗外早期进行支气管镜肺泡灌洗术,对照组采取常规治疗。对比分析2组患者治疗前后的感染指标、动脉血氧饱和度(SaO_(2))、动脉氧分压(PaO_(2))和氧结合指数(PaO_(2)/FiO_(2))、急性生理和慢性健康评分II(APACHEII)、ICU住院天数、28 d的病死率、机械通气时间和体温恢复正常时间。结果(1)观察组在治疗1周后的降钙素原和C反应蛋白指标明显低于对照组(P<0.05);(2)观察组在治疗1周后的SaO_(2)、PaO_(2)、PaO_(2)/FiO_(2)比对照组高,差异有统计学意义(P<0.05);(3)观察组在治疗1周后,APACHEII评分明显低于对照组,差异有统计学意义(P<0.05);观察组机械通气时间、体温恢复时间均短于对照组,差异有统计学意义(P<0.05);观察组28 d病死率明显低于对照组,但差异无统计学意义(P>0.05);2组患者ICU的住院时间比较差异无统计学意义(P>0.05)。结论早期介入支气管镜肺泡灌洗术治疗艾滋病并发重症肺炎患者,可有效地降低感染指标,减轻机体的炎症性反应,改善氧合,减少有创机械通气时间,对改善预后、提升临床救治效能有重要的意义,值得在临床上应用和普及。

Trace determination and characterization of ginsenosides in rat plasma through magnetic dispersive solid-phase extraction based on core-shell polydopamine-coated magnetic nanoparticles

Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging.This study presented a one-pot synthesis of magnetic polydopamine nanoparticles(Fe3O4@-SiO2@PDA NPs)with multiple recognition sites for the magnetic dispersive solid-phase extraction(MDSPE)of ginsenosides from rat plasma treated with white ginseng.The extracted ginsenosides were characterized by combining an ultra-high-performance liquid chromatography coupled to a highresolution mass spectrometry with supplemental UNIFI libraries.Response surface methodology was statistically used to optimize the extraction procedure of the ginsenosides.The reusability of Fe3O4@-SiO2@PDA NPs was also examined and the results showed that the recovery rate exceeded 80%after recycling 6 times.Furthermore,the proposed method showed greater enrichment efficiency and could rapidly determine and characterize 23 ginsenoside prototypes and metabolites from plasma.In comparison,conventional methanol method can only detect 8 ginsenosides from the same plasma samples.The proposed approach can provide methodological reference for the trace determination and characterization of different bioactive ingredients and metabolites of traditional Chinese medicines and food.

Oral and maxillofacial pain as the first sign of metastasis of an occult primary tumour:A fifteen-year retrospective study

BACKGROUND Metastatic adenocarcinoma of the jaw(MAJ)is a rare disease that accounts for 1%-3%of all oral and maxillofacial malignant tumours.Oral and maxillofacial pain may be the first symptom of metastatic spread of an occult primary tumour.Therefore,early identification of oral and maxillofacial pain by dental professionals is critical.AIM To explore the clinical and computerized tomography(CT)features of MAJ with oral and maxillofacial pain as the first symptom.METHODS The medical records of all patients who were treated in our hospital between January 2006 and February 2020,and diagnosed with MAJ with oral and maxillofacial pain as the first symptom,were reviewed retrospectively.Clinical data were collected on age,sex,medical history,clinical manifestations,site of metastasis,and site of the primary lesion.CT features were analysed in detail,and a radiological classification scheme comprising five types:Osteolytic,osteoblastic,mixed,cystic,and alveolar bone resorption was proposed.RESULTS The primary sites of MAJ were the lungs(n=6),liver(n=4),kidneys(n=2),prostate(n=1),and gastric cardia(n=1).Five tumours were classified as the osteolytic type,all with a permeative margin(100%,P<0.05),and three were classified as the mixed type,mostly with a moth-eaten margin(80%,P<0.05).The cystic(n=3)and alveolar bone resorption(n=1)types had geographic margins,and the osteoblastic type(n=1)had sclerotic margins.Moreover,nine tumours showed periosteal reaction and five showed a localised soft tissue mass,while the occurrence of jaw expansion was relatively rare.CONCLUSION MAJ has complex clinical and CT features.Oral and maxillofacial pain may be the first sign of a primary tumour affecting other sites.

基于CiteSpace的国内外城市植物多样性研究对比分析

为了综合比较国内外城市植物多样性的研究进展,采用CiteSpace可视化软件分别对中国知网(CNKI)数据库和“WOS核心合集”数据库进行检索。从年发文量趋势、主要研究作者、机构、热点及趋势四个方面进行对比分析,得出以下结论:①国内研究经历了3个阶段:1998-2002的起步阶段、2003-2010年的探索阶段、2011-2020的稳定阶段;国外研究经历了两个阶段:2002-2008年的起步阶段和2009-2020年的快速发展阶段。②国内发文量较高的研究团队相对集中,且数量较少,合作关系相对不紧密;国外的研究者们则形成了相对稳定且数量较多的合作关系。③国内的研究机构主要集中在各大高校,且彼此间的合作较少,至多以3个机构之间形成合作关系;国外的研究机构则彼此间合作紧密。④国内的研究需丰富研究内容,扩大研究尺度,加强作者和机构之间的合作,逐步推进城市植物多样性的保护研究。生态系统服务和功能多样性将会是国内外今后的研究热点。

Sonar Image Detection Algorithm Based on Two-Phase Manifold Partner Clustering

According to the characteristics of sonar image data with manifold feature,the sonar image detection method based on two-phase manifold partner clustering algorithm is proposed. Firstly,K-means block clustering based on euclidean distance is proposed to reduce the data set. Mean value,standard deviation,and gray minimum value are considered as three features based on the relatinship between clustering model and data structure. Then K-means clustering algorithm based on manifold distance is utilized clustering again on the reduced data set to improve the detection efficiency. In K-means clustering algorithm based on manifold distance,line segment length on the manifold is analyzed,and a new power function line segment length is proposed to decrease the computational complexity. In order to quickly calculate the manifold distance,new allsource shortest path as the pretreatment of efficient algorithm is proposed. Based on this,the spatial feature of the image block is added in the three features to get the final precise partner clustering algorithm. The comparison with the other typical clustering algorithms demonstrates that the proposed algorithm gets good detection result. And it has better adaptability by experiments of the different real sonar images.