基于机器学习的智能出租车预测系统

为了更合理地调度出租车资源,提出基于机器学习的智能出租车预测系统.首先,对波尔图出租车GPS数据集进行分割处理,并抽取其中的一部分作为研究对象;接着利用回声状态网络算法预测旅行目的地;最后利用随机森林算法在相同情况下预测出租车抵达时间.实验表明本系统能根据当前的波尔图出租车GPS数据集预测出实际出租车某段旅程的目的地和旅程所需要的时间,以达到减少出租车资源浪费的目的.福建省自然科学基金(2017J01739);;福建师范大学教学改革研究项目(I201602015)~

Therapeutic Efficacy and Safety of Different Therapy Schemes of Itraconazole versus Terbinafine in the Treatment of Onychomycosis:A Meta-analysis

目的:系统评价伊曲康唑不同治疗方案对比特比萘芬治疗甲真菌病的临床疗效与安全性,以为临床治疗提供循证参考。方法:计算机检索Pub MEd、EMbASE、MEdlInE、THE COCHrAnE lIbrAry、中国期刊全文数据库、维普中文科技期刊全文数据库、万方数字化期刊全文库,收集伊曲康唑对比特比萘芬治疗甲真菌病的随机对照试验(rCT),提取资料并评价质量后,采用rEV MAn 5.2统计软件进行META分析。结果:共纳入11项rCT,合计1 886例患者。META分析结果显示,伊曲康唑连续治疗的临床治愈率[rr=0.94,95%CI(0.76,1.18),P=0.61]与特比萘芬比较差异无统计学意义,而真菌学治愈率[rr=0.80,95%CI(0.68,0.95),P=0.01]和总治愈率低于特比萘芬,两组比较差异有统计学意义;伊曲康唑冲击治疗的临床治愈率[rr=0.75,95%CI(0.65,0.87),P<0.000]和总治愈率[Or=0.39,95%CI(0.27,0.55),P<0.000]低于特比萘芬,而真菌学治愈率与特比萘芬比较差异无统计学意义[rr=0.82,95%CI(0.63,1.07),P=0.14];两组患者消化系统不良反应发生率比较,差异无统计学意义[Or=1.02,95%CI(0.83,1.25),P=0.86]。结论:伊曲康唑不同治疗方案治疗甲真菌病的疗效均低于特比萘芬,安全性相似。由于纳入研究数量较少、质量一般,该结论尚有待大样本、高质量的rCT进一步验证。OBJECTIVE:To evaluate the therapeutic efficacy and safety of different therapy schemes of itraconazole versus terbinafine in the treatment of onychomycosis,and to provide evidence-based reference for clinical treatment.METHODS:Retrieved from Pub Med, EMBase, Medline,The Cochrane Library, CNKI,VIP and Wanfang database, randomized controlled trials(RCTs)about itraconazole vs.terbinafine in the treatment of onychomycosis were collected.Meta-analysis was performed by using Rev Man 5.2 statistical software after evaluating the quality of included studies and extracting data.RESULTS:11 RCTs were included,involving 1 886 patients.Meta-analysis showed that:there was no statistical significance in cure rate between itraconazole consecutive treatment [RR=0.94,95% CI(0.76,1.18),P=0.61] and terbinafine;the mycological cure rate [RR=0.80,95% CI(0.68,0.95),P=0.01] and total cure rate of itraconazole consecutive treatment were lower than those of terbinafine;there was statistical significance.The clinical cure rate [RR=0.75,95%CI(0.65,0.87),P<0.000] and total cure rate [OR=0.39,95%CI(0.27,0.55),P<0.000] of itraconazole pulse therapy were lower than those of terbinafine;there was no significant difference in mycological cure rate between 2 groups [RR=0.82,95%CI(0.63,1.07),P=0.14].There was no significant difference of the incidence of digestive system adverse reactions between 2 groups[OR=1.02,95%CI(0.83,1.25),P=0.86].CONCLUSIONS:Therapeutic efficacy of different schemes of itraconazole is lower than terbinafine in the treatment of onychomycosis.More large-scale and high quality RCTs are required for further validation due to small scale and ordinary quality of include studies.国家科技支撑计划子课题(No.2013BAI06B04Y023081

若尔盖高寒湿地土壤活性有机碳垂直分布特征

对若尔盖高寒湿地沼泽土和泥炭土的有机碳(TOC)和活性有机碳(LC)沿土壤剖面的分布特征研究表明,沼泽土的有机碳和全氮(TN)含量整体上从表层向下呈现下降趋势,中间在16~18 cm处出现一个升高点,与当时的有机质来源和沉积环境有关。泥炭土有机碳沿土壤剖面并没有呈现同样的下降趋势,而是从表层向下至22cm呈现升高趋势,22 cm向下才呈现下降趋势,全氮含量与有机碳含量的分布特征不同,在表层0~10 cm含量较高,向下含量减小。沼泽土活性有机碳沿土壤剖面整体呈现下降趋势,变化于2.4~13.6 m g/g,变异系数较大,达到53.25%。泥炭土活性有机碳沿土壤剖面规律性不明显,变化于30~45 m g/g,变异系数只有11.62%。沼泽土的活性有机碳占到总有机碳的3%~17%,变化较大;而泥炭土的活性有机碳占到总有机碳的7%~12%,变化较小。沼泽土和泥炭土的有机碳活度(L)最大值并不是出现在表层,而是在表层稍微向下的部分(8~10 cm),再向下有机碳活度呈现下降的趋势

Effects of BaP exposure on ultrastructures of hepatic cells of Boleophthalmus pectinirostris.

在实验生态条件下,研究不同浓度苯并(a)芘(BaP)暴露下大弹涂鱼肝脏细胞超微结构的变化.结果表明,暴露于低浓度(0.5 mg·L-1)BaP 7 d,大弹涂鱼肝脏细胞内的细胞器受到不同程度的损伤,其中线粒体和内质网是受BaP暴露影响最明显的细胞器,细胞核也受到不同程度的影响,细胞质中脂滴也增加;而暴露于高浓度(5 mg·L-1)BaP 2 h,不仅是线粒体和内质网,几乎所有细胞器都受到严重影响,细胞器严重退化,细胞结构遭到严重破坏.研究结果证实,BaP可对大弹涂鱼肝细胞内多种细胞器造成损伤,并且BaP浓度越高,损伤程度越严重.The changes of ultrastructures of hepatic cells of Boleophthalmus pectinirostris were investigated after the fish were exposed under benzo (a) pyrene in different concentrations under experimental condition. The results showed that the organelles in hepatic cells of B. pectinirostris were damaged to different extents after the fish was exposed under lower concentration of BaP (0.5 mg·L-1) for up to 7 d, in which, mitochondria and endo-plasmic reticulum were the chief organelles affected by BaP exposure. While the fish was exposed under higher concentration of BaP (5 mg·L-1 ) for 2 h, almost all of the organelles including mitochondria and endoplasmic reticulum in hepatic cells of B. pectinirostr were affected by BaP exposure. The structures of liver cells were seriously damaged. It was demonstrated that BaP could produce multiorganalle lesions in hepatic cells of B. pectinirostris, and the severity extent of such lesions was dependent on the concentration level of BaP.国家自然科学基金资助项目(49876029

若尔盖高寒湿地土壤氮矿化对温度和湿度的响应

采用原状土矿化培养方法研究了温度和湿度及其交互作用对青藏高原若尔盖湿地土壤(沼泽土和泥炭土)氮矿化的影响。研究表明,氮矿化速率在5~15℃之间对温度的反应较弱,而超过15℃时矿化速率则明显增加;泥炭土的氮矿化速率对温度的响应比沼泽土要敏感;氮矿化速率对淹水和非淹水响应敏感;除了在淹水条件下土壤的温度系数Q10在15~25℃之间较大(4.4左右)外,其余温度和湿度下大致在1~2之间,说明了淹水条件下氮矿化对温度响应最敏感的范围在15~25℃之间

optical densitometric study on thermal stabilization of polyacrylonitrile fibers

采用梯度升温曲线,在170～310 ℃内,每间隔10 min升高10 ℃对聚丙烯腈(PAN)纤维进行热处理,使用光密度法研究了PAN纤维的热稳定化.结果表明:PAN纤维在热稳定化过程中光密度发生了变化,热稳定化过程中纤维表面会发生反应生成致密的氧化层,导致皮芯结构的形成.光密度法是系统研究PAN纤维热稳定化程度与氧化均匀性的理想方法,具有良好的准确性灵敏性;引入了光密度标准差有效评估PAN纤维皮芯结构程度

热解法石墨纤维镀银研究

采用含银浆液浸渍涂层和热解法在石墨纤维表面镀银,采用扫描电子显微镜、X射线能谱仪和电阻率测试仪研究了含银浆液和石墨纤维的石墨化程度对镀银结构的影响。结果表明:含质量分数5%硝酸银的聚丙烯水性乳液型浆液的使用效果最好,在石墨纤维表面形成了大量均匀分散的纳米银颗粒,大幅降低了石墨纤维的电阻率;但大幅提高浆液中硝酸银的浓度,反而会对石墨纤维表面的镀银结构产生不利影响。该方法简单、高效、容易实现连续化生产,可以制得用于金属基复合材料或具有特殊功能的石墨纤维