基于熔体静电纺丝技术制备一种金属-有机骨架复合材料的方法

高性能金属-有机骨架(MOFs)复合材料是目前研究热点。文中首次采用熔体静电纺丝法制备了低密度聚乙烯(LDPE)纤维作为沉积MOFs晶体的衬底,并采用溶剂热合成法原位制备了负载锆基金属-有机骨架材料(UiO-66)的LDPE纤维复合材料。通过扫描电子显微镜(SEM)、X射线衍射(XRD)、傅里叶变换红外光谱分析(FT-IR)和热重分析(TG),对UiO-66@PE纤维复合材料的表面形貌和结构进行了表征。结果表明,UiO-66@PE复合纤维材料最佳制备温度是100℃,它是由UiO-66包裹的纤维态复合材料,且晶体较均匀负载于LDPE纤维表面,UiO-66晶体直径为190~900 nm;FT-IR分析表明UiO-66晶体与LDPE纤维之间没有化学作用;TG分析结果表明,相比基材LDPE,UiO-66@PE复合材料的热分解温度有所提高,能够达到425℃。

Synergistic effects of ginseng stem and leaf-extracted ginsenoside and choline on improving learning and memory in rats Association verification experiment in animals with multiple learning and memory disorders

BACKGROUND： Ginsenoside extracted from the stem and leaf of ginseng （GSL） and choline have both been shown to improve learning and memory functions; however, further studies are needed to understand the synergistic effects of a combination of both. OBJECTIVE： To verify the combined improved synergistic effects of GSL and choline on learning and memory disorders in rats. DESIGN： Control observation. SETTING： Taishan Medical College. MATERIALS： A total of 150 male Kunming mice weighing （204-2） g and 40 healthy male Wistar rats weighing （2204-20） g were provided by the Experimental Animal Department of Jilin University. Animal experimentation received confirmed consent from the local ethic committee. GSL was provided by the Department of Chemistry, Norman Bethune Medical University, and choline was provided by the Third Experiment Factory, Shanghai. METHODS： This study was performed at the Life Science Institute, Taishan Medical College from October 2006 to February 2007. ① Scopolamine-induced learning and memory disorders in rats： Forty rats were randomly divided into control group, model group, combination group （400 mg/kg GSL ＋ 200 mg/kg choline）, GSL （400 mg/kg） group, and choline （200 mg/kg） group, 8 rats/group. Rats were perfused and administrated in the morning, once a day for 14 successive days. Rats in the control group and model group were perfused with 20 mL/kg distilled water and underwent Morris water maze spatial resolution test 1 hour after perfusion on the 10m, 11m, and 12m days after administration. Rats also underwent passive step-down avoidance test 1 hour after reperfusion on the 13m and 14m days after administration. Thirty minutes prior to experimentation, rats in the remaining three groups were intraperitoneally （i.p） injected with 2 mg/kg scopolamine, and rats in the control group were i.p. injected with 2 mL/kg saline. ② Scopolamine-induced learning disorder and memory acquired disorder in mice： Fifty mice were randomly divided into control group, model group, combination group （400 mg/kg GSL ＋200 mg/kg choline）, GSL （400 mg/kg） group, and choline （200 mg/kg） group, with 10 mice/group. Mice were perfused and administrated in the morning, once a day for 9 successive days. Mice in the control group and model group were perfused with 20 mL/kg distilled water and underwent passive step down avoidance test 1 hour after reperfusion on the 8th and 9th day after administration. Twenty minutes prior to training, mice in the remaining three groups were i.p. injected with 2 mg/kg scopolamine, and mice in the control group were i.p. injected with 10 mL/kg saline. ③ Sodium nitrite-induced memory consolidation disorder in mice： Grouping, administration, and testing were the same as mentioned above. After training, mice in the remaining three groups were immediately subcutaneously injected with 120 mg/kg sodium nitrite, and mice in the control group were subcutaneously injected with 20 mL/kg saline. ④ Ethanol-induced memory reconsolidation disorder in mice： Grouping, administration, and testing were the same as mentioned above. At 24 hours after training and 20 minutes before retraining, mice in the remaining four groups were perfused with 10 mL/kg ethanol （0.3 volume fraction）, and mice in the control group were perfused with 10 mL/kg saline. MAIN OUTCOME MEASURES： Synergistic effects of GSL and choline on learning and memory deficits induced by scopolamine, sodium nitrite, and ethanol in experimental animals. RESULTS： All 40 rats and 150 mice were included in the final analysis. ① Synergistic effects of GSL and choline on learning and memory disorders induced by scopolamine in rats： During passive step-down avoidance and Morris water maze spatial resolution tests, the number of error responses and length of maze training in the model group were significantly greater than in the control group （P 〈 0.01）; while the number of error responses and length of maze training in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combining administration, which suggests that the combination of GSL and choline had synergistic effects. ② Synergistic effects of GSL and choline on learning disorder and memory-acquired disorder induced by scopolamine in mice： During passive step-down avoidance test, the number of error responses in the model group were significantly greater than in the control group （P 〈 0.01 ）; while the number of error responses in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combining administration, which suggests GSL and choline had synergistic effects. ③ Synergistic effects of GSL and choline on memory sodium nitrate-induced consolidation disorder in mice： During passive step down avoidance test, the number of error responses in the model group were significantly less than in the control group （P 〈 0.01 ）; while the number of error responses in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combined administration, which suggests GSL and choline had synergistic effects. ④ Synergistic effects of GSL and choline on ethanol-induced memory reconsolidation disorder in mice： During passive step down avoidance test, the number of error responses in the model group were significantly greater than in the control group （P 〈 0.01）; while the number of error responses in the combination group were significantly less than in the model group, GSL group, and choline group （P 〈 0.05-0.01）. The Q value was 〉 1 after combined administration, which suggests GSL and choline had synergistic effects. CONCLUSION： GSL and choline have synergistic effects on learning and memory functions.

Effects of ginsenoside of stem and leaf combined with choline on learning and memory ability of rat models with Alzheimer diseases

BACKGROUND： Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf （GSL） can improve functions of central adrenergic nerve; moreover, 5-serotonergic nerve and the combination with choline can produce synergistic effect and enhance learning and memory ability so as to improve learning and memory disorder of patients with Alzheimer disease （AD）. OBJECTIVE ： To observe the effects of GSL combining with choline on learning and memory of AD model rats DESIGN ： Randomized grouping design and controlled animal study SETIING ： Department of Pharmacology, Taishan Medical College MATERIALS ： The experiment was carried out in the Pharmacological Department of Medical College of Jilin University from October 1996 to January 1997. Forty healthy male Wistar rats of clean grade were randomly divided into 5 groups, including sham-injury group, model group, GSL group, choline group and combination group, with 8 rats in each group. Main medications： GSL with the volume more than 92.8% was provided by Department of Chemistry, Norman Bethune Medical College of Jilin University. Panaxatriol, the main component, was detected with thin layer scanning technique and regarded as the index of GSL quality [（55±1）%, CV= 2%, n = 5]. Choline was provided by the Third Shanghai Laboratory Factory. METHODS ： 150 nmol quinolinic acid was used to damage bilateral Meynert basal nuclei of adult rats so as to establish AD models. Rats in GSL, choline and combination groups were intragastric administrated with 400 mg/kg GSL, 200 mg/kg choline （20 mL/kg）, and both respectively last for 17 days starting from two days before operation. Rats in sham-injury group and model group were perfused with the same volume of distilled water once in each morning for the same days. （1） Passive avoidance step-down test： Five minutes later, rats jumped up safe platform when they were shocked with 36 V alternating current. If rats jumped down from the platform and the feet touched railings, the response was wrong. Numbers of wrong response were recorded within 3 minutes, and then the test was redone after 24 hours. （2） Morris water-maze spatial localization task： Swimming from jumping-off to platform directly was regarded as right response. Additionally, 4 successively right responses were regarded as the standard. Each rat was trained 10 times a day with 120 s per time for 3 successive days. The interval was 30 s. Three days later, numbers of right response were recorded. The training times were increased to 30 for unlearned rats. （3） Measurement of activity of choline acetylase in cerebral cortex： Rats were sacrificed at 17 days after operation to obtain cerebral cortex to measure activity of choline acetylase with radiochemistry technique. （4） Synergistic effect： It was expressed as Q value： Q value = factual incorporative effect/anticipant incorporative effect; Q ≥ 1 was regarded as synergistic effect. Anticipant incorporative effect = （EA＋EB-EA·EB）, EA and EB were single timing effect, respectively in GSL group and choline group. E（step-down test and Morris water maze test） = （x in model group - factual value in medicine groups）/x in model group; E （activity of choline acetylase） = （factual value in medicine groups -xin model group）/xin model group. MAIN OUTCOME MEASURES ： （1） Passive avoidance step-down test and Morris water-maze spatial localization task in the study of learning and memory; （2） activity of choline acetylase. RESULTS ： All 40 rats were involved in the final analysis. （1） Passive avoidance response： At learning phase on first day and retesting phase on the next day, numbers of wrong responses within 3 minutes were more in model group than sham operation group, and there was significant difference [（5.88±1.46）, （2.25±0.87） times; （2.63±1.06）, （0.50±0.53） times; P 〈 0.01]; numbers of wrong responses within 3 minutes were less in combination group than model group, and there was significant difference [learning phase： （1.12±0.83）, （5.88±1.46） times; retesting phase： （0.38±0.74）, （2.63±1.06）times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and 1.59, respectively and it showed synergistic effect. Spatial localization task： Training times were more in model group than sham operation group, and there was significant difference [（2.9±2.5）, （12.6±3.5） times; P 〈 0.01]. Training times were less in combination group than model group, and there was significant difference [（11.8±2.4）, （27.9±2.5） times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and it showed synergistic effect. （3） Activity of choline acetylase： Activity was lower in model group than sham operation group, and there was significant difference [（30.56±8.33）, （61.11 ±8.33） nkat/g; P 〈 0.01]. Activity was higher in combination group than model group and there was significant difference [（50.00±8.33）, （30.56±8.33） nkat/g, P 〈 0.01];moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.5 and it showed synergistic effect. CONCLUSZON： GSL in combination with choline can synergically improve the disorder of learning and memory of AD model rats. Its mechanism may be involved in enhancing the function of central cholinergic system.

Data-Centric Routing Mechanism Using Hash-Value in Wireless Sensor Network

Traditional routing protocols as TCP/IP can not be directly used in WSN, so special data-centric routing protocols must be established. The raised data-centric routing protocols can not identify the sensor nodes, because many nodes work under a monitoring task, and the source of data is not so important some times. The sensor node in the network can not judge weather data is come from the some sink node. What’s more, the traditional method use IP to identify sensors in Internet is not suitable for WSN. In this paper, we propose a new naming scheme to identify sensor nodes, which based on a description of sensor node, the description of a sensor node is hashed to a hash value to identify this sensor. The different description generates different identifier. Different from IP schema, this identifier is something about the information of the sensor node. In the above naming scheme, we propose a new data-centric routing mechanism. Finally, the simulation of the routing mechanism is carried out on MATLAB. The result shows our routing mechanism’s predominate increase when network size increase.

Impact of Air Pollution on Skin

Recent articles reviewed the molecular damaging pathway of various pollutants especially PM2.5 particles and polycylic aromatic hydrocarbon. AhR （aryl hydrocarbon receptor） pathway, tobacco-similar pathway, oxidation, as well as epigenetics pathway were reviewed. Based on the working mechanism, the reported study method and methodology used in Ashland lab were reviewed, including cell level experiment, through reconstructed human skin to in vivo study.

Intrauterine Treatment of Monochorionic Triamniotic Triplet Pregnancy with Twin Reverse Arterial Perfusion Sequence

To editor:This study reports a pregnant woman who was naturally conceived with monochorionic triamniotic(MCTA)combined with twin reversed arterial perfusion(TRAP).An ultrasound revealed that one of the fetuses had a cardiac malformation,and a connection between the umbilical arteries was suspected.To reduce the acardiac fetus,radiofrequency ablation was performed at 17+3 weeks of pregnancy.At 36+4 weeks,two healthy infants were delivered via elective cesarean section.Postoperative examination revealed a direct connection between the umbilical arteries,with the placental perfusion acting as a direct pump.It is essential to identify the intrauterine status of the blood-supplying infant and vascular connections in order to achieve successful outcomes in pregnancies with complications,such as edema and heart failure.The studies involving human participants were reviewed and approved by Human Research Ethics Committee of Tianjin Central Hospital of Obstetrics and Gynecology.The patient provided her written informed consent to participate in this study.

Rational construction of genome-minimized Streptomyces host for the expression of secondary metabolite gene clusters

Streptomyces offer a wealth of naturally occurring compounds with diverse structures,many of which possess significant pharmaceutical values.However,new product exploration and increased yield of specific compounds in Streptomyces have been technically challenging due to their slow growth rate,complex culture conditions and intricate genetic backgrounds.In this study,we screened dozens of Streptomyces strains inhabiting in a plant rhizosphere for fast-growing candidates,and further employed CRISPR/Cas-based engineering techniques for stepwise refinement of a particular strain,Streptomyces sp.A-14 that harbors a 7.47 Mb genome.After strategic removal of nonessential genomic regions and most gene clusters,we reduced its genome size to 6.13 Mb,while preserving its growth rate to the greatest extent.We further demonstrated that cleaner metabolic background of this engineered strain was well suited for the expression and characterization of heterologous gene clusters,including the biosynthetic pathways of actinorhodin and polycyclic tetramate macrolactams.Moreover,this streamlined genome is anticipated to facilitate directing the metabolic flux towards the production of desired compounds and increasing their yields.

射频消融减胎术后并发羊膜带综合征1例

本文报道了1例射频消融减胎术后胎儿并发羊膜带综合征并成功救治的病例。孕妇为自然受孕单绒毛膜双羊膜囊双胎,孕24周产前超声提示双胎输血综合征Ⅲ期,孕妇知情同意选择射频消融减胎术,手术过程顺利。孕28周+6复查超声提示胎儿左足明显水肿,足踝处可见带状物缠绕,并可见勒痕及缩窄环,多学科会诊考虑羊膜带综合征ⅡB期。当日急诊剖宫产娩一活男婴。新生儿左足踝处可见细羊膜带缠绕数周,勒痕明显,深入皮肤1 cm,足背、足底及足踝下方水肿明显。紧急行左足羊膜带松解术,术后水肿渐消退,随访至28日龄,新生儿下肢恢复正常。

Extracellular vesicles derived from neural EGFL-Like 1-modified mesenchymal stem cells improve acellular bone regeneration via the miR-25-5p-SMAD2 signaling axis

Stem cell based transplants effectively regenerate tissues;however, limitations such as immune rejection and teratoma formation prevent their application. Extracellular vesicles (EVs)-mediated acellular tissue regeneration is a promising alternative to stem cell based transplants. Although neural EGFL-like 1 (Nell1) is known to contribute to the osteogenic differentiation of bone marrow stem cells (BMSCs), it remains unknown whether EVs are involved in this process. Here, we present that EVs derived from Nell1-modified BMSCs (Nell1/EVs) have a stronger ability to promote BMSC osteogenesis owing to miR-25–5p downregulation. MiR-25–5p inhibits osteogenesis by targeting Smad2 and suppressing the SMAD and extracellular signal-related kinase 1 and 2 (ERK1/2) pathway activation. In addition, we demonstrate that the 3D-Nell1/EV-hydrogel system is beneficial for bone regeneration in vivo, probably stemming from a slow, continuous release and high concentration of EVs in the bone defect area. Thus, our results have shown the potential of Nell1/EVs as a novel acellular bone regeneration strategy. Mechanistically, the identification of miR-25-5p-SMAD2 signaling axis expands the knowledge of Nell1/EVs induced osteogenesis.

Quantum machine learning of eco-environmental surfaces

The computer advances of the past century can be traced to the increase in their numbers on chips that has accompanied the miniaturization of transistors.However,computers are nearing the fundamental limits of such miniaturization[1].Many practical problems require huge amounts of computational resources that exceed the capabilities of today's computers.A 54-qubit quantum computer on the other hand can solve in minutes a problem that would take a classical machine 10,000 years[2].

AFExplorer:Visual analysis and interactive selection of audio features

Acoustic quality detection is vital in the manufactured products quality control field since it represents the conditions of machines or products.Recent work employed machine learning models in manufactured audio data to detect anomalous patterns.A major challenge is how to select applicable audio features to meliorate model’s accuracy and precision.To relax this challenge,we extract and analyze three audio feature types including Time Domain Feature,Frequency Domain Feature,and Cepstrum Feature to help identify the potential linear and non-linear relationships.In addition,we design a visual analysis system,namely AFExplorer,to assist data scientists in extracting audio features and selecting potential feature combinations.AFExplorer integrates four main views to present detailed distribution and relevance of the audio features,which helps users observe the impact of features visually in the feature selection.We perform the case study with AFExplore according to the ToyADMOS and MIMII Dataset to demonstrate the usability and effectiveness of the proposed system.

Study of tribological properties and lubrication mechanism of surfactant-coated anthracite sheets used as lubricant additives

Anthracite sheets were coated by sorbitol fatty acid ester(span80)through ball-milling process.The tribological properties of the span80-coated anthracite sheets as the additive in polyalpha olefin were evaluated through a series of friction tests using a four ball machine.The results revealed that the span80-coated anthracite sheets exhibited excellent dispersion stability in base oil.In addition,compared with base oil,the average coefficient of friction,wear scar diameter,and wear volume of modified oil at a mass fraction of 0.03%span80-coated anthracite sheets decreased by 45.39%,60.13%,and 95.95%,respectively.The oil containing span80-coated anthracite sheets achieved good friction-reducing and anti-wear effects over a wide range of applied loads,temperatures,or rotating speeds.Control experiments were performed as well.The results obtained using span80-coated anthracite sheets were superior to those obtained using pure anthracite.The lubrication mechanism was attributed to the synergistic action of the crystalline and amorphous carbon in anthracite sheets as they formed a protective film and played a mitigative role on the surface of friction pair,which mitigated the wear extent of the friction pair.