棉花品种间土壤Nmin异同及氮肥推荐技术研究

在滴灌条件下,利用流动分析仪测定基因型差异较大的陆地棉和海岛棉在不同施氮水平下,各主要生育期0~60 cm土壤无机氮含量,对土壤氮素营养诊断及氮肥推荐技术基因型间的异同进行试验研究。结果表明:不同棉花品种0~20 cm土壤Nmin含量与施氮量和产量均有显著的正相关关系,采样深度增加相关性降低,品种间基肥和追肥总量氮肥推荐指标差异不显著,可采用同一标准。但由于2个品种各时期吸收氮的能力不同,不同品种主要生育时期最佳供氮量,植株全氮含量和收获后0~60 cm土壤硝态氮残留量都有一定差异

腹部术后肺部并发症患者呼出气挥发性有机化合物分析

目的确定与腹部手术后患者发生术后肺部并发症（PPCs）相关的特征性呼出气挥发性有机化合物（VOCs）。方法本研究前瞻性、连续入组2022年12月10日至2023年6月30日在北京大学人民医院行腹部手术后转入重症监护病房（ICU）带气管插管的患者76例。采集患者围术期相关基本信息，并在患者入ICU后的24 h内经气管插管采集患者呼出气，进行气相色谱-质谱联用检测（GC-MS），分析患者呼出气VOCs成分。观察患者术后24 h采集呼出气后是否发生PPCs，将患者分为PPCs（n=44）组和无PPCs组（n=32），比较患病组和非患病组呼出气VOCs差异。应用Lasso回归分析筛选有价值VOCs变量，进而行Logistics回归分析，确定和PPCs相关的特征性VOCs。结果76例患者中发生PPCs者44例，无PPCs者32例，针对两组患者呼出气VOCs行Lasso回归分析，筛选出和PPCs可能相关的4种化合物，将4种化合物带入多因素Logistics回归分析，最终结果显示呼出气1-十六烷醇含量增高和PPCs的发生相关（OR： 1.000， P=0.002）。结论本研究显示腹部手术后患者呼出气中1-十六烷醇含量升高可能和PPCs的发生相关

颅痛煎对偏头痛患者超敏C反应蛋白影响及疗效观察

目的探讨超敏C反应蛋白(hs-CRP)的变化与偏头痛发病机制的关系,观察颅痛煎治疗偏头痛疗效及对hs-CRP的影响。方法选取65例偏头痛患者和30例健康人进行检测hs-CRP,再将65例病人随机分为颅痛煎汤治疗组(简称颅头煎组)32例,给予颅痛煎,一日一剂,水煎分2次服;西比灵对照组(简称西比灵组)33例,给于西比灵5mg,一天1次,谷维素20mg,一天3次。共治疗28天后。观察两组患者的治疗前后疼痛程度、持续时间、发作频度及检测hs-CRP,计算其头痛指数和头痛疗效。结果偏头痛组hs-CRP含量明显高于正常对照组(P<0.01),治疗后颅痛煎组的hs-CRP水平明显低于西比林组(P<0.05),颅痛煎组的临床基本恢复、总有效率、头痛指数明显好于西比灵组(P<0.01、<0.05)。结论 hs-CRP的增高与偏头痛的发生有关,颅痛煎治疗偏头痛疗效明显优于西比灵,可能与颅痛煎降低偏头痛患者的hs-CRP有关

Preparation and Photoeletrochemical Performance of CdS Quantum Dot Sensitized ZnO Nanorod Array Electrodes

Corresponding author. Email: [email protected]; Tel: +86-592-2189663[中文文摘]采用连续式离子层吸附与反应法制备了CdS量子点敏化的ZnO纳米棒电极.应用扫描电子显微镜(SEM)、X射线衍射(XRD)和透射电子显微镜(TEM)对CdS量子点/ZnO纳米棒电极的形貌、晶型和颗粒尺寸进行了分析和表征;采用光电流-电位曲线和光电流谱研究了不同CdS循环沉积次数及不同沉积浓度对复合电极的光电性能影响.结果表明,前驱体浓度都为0.1mol·L-1且沉积15次敏化后的ZnO纳米棒阵列电极光电性能最好.与单纯的ZnO纳米棒阵列电极和单纯的CdS量子点电极相比,其光电转换效率显著提高,单色光光子-电流转换效率(IPCE)在380nm处达到76%.这是因为CdS量子点可以拓宽光的吸收到可见光区,并且在所形成的界面上光生载流子更容易分离.荧光光谱实验进一步说明了光电增强的原因是,两者间形成的界面中表面态大大减少,有利于减少光生电子和空穴的复合. [英文文摘]We sensitized CdS quantum dots on a ZnO nanorod array electrode by the successive ionic layer adsorption and reaction method.Scanning electron microscopy(SEM),X-ray diffraction(XRD),and transmission electron microscopy(TEM) experiments were performed to characterize the morphology,crystalline phase,and grain size of the CdS quantum dot sensitized ZnO nanorod array electrodes.The effect of CdS deposition cycle number and the precursor concentration were studied by photocurrent-potential characteristics and photocurrent spectra. The results showed that the best photoelectrochemical performance was obtained at 0.1 mol·L-1 for both Cd2+ and S2- after 15 cycles. Meanwhile, the composite films exhibited a remarkably enhanced photoelectric conversion efficiency compared with the ZnO nanorods array films and with CdS quantum dot electrodes. The monochromatic incident photon-toelectron conversion efficiency (IPCE) was as high as 76% at 380 nm. This may be attributed to the broad light harvesting capability of CdS and the efficient separation of photogenerated carriers on its interface. The reason for this enhancement was further confirmed by a photoluminescent experiment. The results showed that sensitization with CdS quantum dots reduced the recombination of electron and hole pairs resulting in an enhancement in the photocurrent.国家自然科学基金(20433040

Development of Electrochemical Biosensor for Detection of PML/RARα Fusion Gene in Acute Promyelocytic Leukemia

针对急性早幼粒细胞白血病(APl)中PMl/rArα融合基因的碱基序列,设计了锁核酸(lnA)修饰的发夹结构捕获探针,结合信号探针构建新型的“三明治“电化学传感模式。信号探针末端修饰的生物素可与酶上的亲和素结合,通过检测酶催化H2O2氧化底物3,3',5,5'-四甲基联苯胺(TMb)产生的电化学信号,实现对靶序列的检测。该传感器可识别和定量检测PbS缓冲液中人工合成的PMl/rArα融合基因序列。结果表明,该传感器能很好地区分互补序列、单碱基及多碱基错配序列,杂交电流值与目标链浓度在1.0x10-11~1.6x10-10 MOl/l范围内呈较好的线性关系,检出限为1.0x10-13 MOl/l。同时,该新型传感器成功地用于无稀释人血清中PMl/rArα融合基因的检测,具有特异性强、灵敏度高和重复性好的优点,有望用于临床实际样品的检测,进而实现临床上急性早幼粒细胞白血病的早期诊断及预后判断。A novel DNA electrochemical probe(locked nucleic acid,LNA) was designed and involved in constructing an electrochemical DNA biosensor for the detection of PML/RARα fusion gene in acute promyelocytic leukemia(APL).This biosensor was based on a "sandwich" detection strategy,which involved a pair of LNA probes,e.g.hairpin capture probe and reporter probe.Streptavidin-HRP was bound to biotin labeled at the end of reporter probe via streptavidin-biotin affinity binding.In the presence of hydrogen peroxide(H2O2),HRP catalyzed the oxidation of the substrate 3,3′,5,5′-tetramethylbenzidene(TMB) to offer an enzymatically amplified electrochemical current signal for the detection of target DNA.This sensor was applied in the direct quantitative detection of synthetic PML/RARα fusion gene in PBS buffer.The results indicated that the biosensor showed an excellent specificity to distinguish the complementary sequence and different mismatch sequences.A linear relationship between the amperometric signal and the target concentration was obtained in the range of 1.0×10-11-1.6×10-10 mol/L with a detection limit of 1.0×10-13 mol/L.In addition,the biosensor was used for the determination of PML/RARα fusion gene in human serum samples without dilution with high sensitivity,selectivity and good repeatability.This method would be expected to use in real sample for further solving the actural problems of early diagnosis and prognosis monitoring of APL.863计划资助项目(2008AA02Z433);福建省高校产学研科技重点项目(2010Y4003);国家自然科学基金资助项目(20805006;20975021);福建省自然科学基金资助项目(2010J05019

Charge Transport Performance of Nafion-based Redox Polymer in Atmosphere

利用三明治电池和伏安法测试了不同制备条件的Nafion基氧化还原聚合物膜在空气中的电荷传输性能.研究结果表明,混合适量聚乙二醇(PEG)的Nafion基金属联吡啶配合物｛Nafion[M(bpy)23+,PEG](M=Ru,Fe)｝膜的表观电荷传递扩散系数(Dct)达到10-6-10-7cm2·s-1,电子或空穴迁移率(μ)达到10-4-10-5cm2·V-1·s-1.在导电玻璃(ITO)电极与Nafion基氧化还原聚合物膜界面引入一层导电聚苯胺(PANI)后,降低了其接触电阻,使氧化还原聚合物膜的Dct提高至10-5-10-6cm2·s-1,μ提高至10-3-10-4cm2·V-1·s-1,且工作电流提高了近两个数量级.该固态氧化还原聚合物膜的性能比较稳定,在空气中放置30天后其Dct和μ降低得很少.The charge transport performance of the Nafion-based redox polymer films prepared under different conditions was investigated by cyclic voltammetry in the sandwiched cells.The results showed that the apparent charge transfer diffusion coefficient(Dct)of the Nafion[M(bpy)2+3,PEG(polyethylene glycol)](M=Ru or Fe)films is about 10-6-10-7 cm2·s-1 and the mobility of the electron or hole(μ)was about 10-4-10-5 cm2·V-1·s-1.In order to decrease the resistance of the interface,a polyaniline(PANI)layer was added to the interface of indium tin oxide coated conducting glass(ITO)electrode and the redox polymer.Consequentially,the Dct could be increased to about 10-5-10-6 cm2·s-1 and μ to about 10-3-10-4 cm2·V-1·s-1,and the operating current of the cells under 600 mV bias could be increased by almost 100 times.In addition,the Dct and μ of this redox polymer film had just reduced slightly after 30 d kept in atmosphere.Therefore,the redox polymer film is sufficiently stable.国家自然科学基金(20373057)资助项

Charge transport performance of Nafion-based redox polymer in atmosphere

The charge transport performance of the Nafion-based redox polymer films prepared under different conditions was investigated by cyclic voltammetry in the sandwiched cells. The results showed that the apparent charge transfer diffusion coefficient(D-a) of the Nafion[M(bpy)(3)(2+), PEG (polyethylene glycol)] (M=Ru or Fe) films is about 10(-6)-10(-7) cm(2) . s(-1) and the mobility of the electron or hole (mu) was about 10(-4)-10(-5) cm(2) . V-1 . s(-1). In order to decrease the resistance of the interface, a polyaniline (PANI) layer was added to the interface of indium tin oxide coated conducting glass (ITO) electrode and the redox polymer. Consequentially, the D-a could be increased to about 10(-5)-10(-6) cm(2) . s(-1) and mu to about 10(-3)-10(-4) cm(2) . V-1 . s(-1), and the operating current of the cells under 600 mV bias could be increased by almost 100 times. In addition, the D-a and mu of this redox polymer film had just reduced slightly after 30 d kept in atmosphere. Therefore, the redox polymer film is sufficiently stable

论《三国演义》的基本主题

艺术作品的永恒魅力和价值 ,存在于后人对它永无止境的解释之中 ,《三国演义》亦如此。就其本质而言 ,该作品乃一“政治”小说 ,通过作者所刻画的正面主人公的毁灭来确立一种永恒的政治理想与道德准则 ,且在“尊刘抑曹”这一政治主题的背后 ,透露的是一个时期内汉民族的历史意识与价值观