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101.
PLETHORA proteins as dose-dependent master regulators of Arabidopsis root development 总被引:1,自引:0,他引:1
Galinha C Hofhuis H Luijten M Willemsen V Blilou I Heidstra R Scheres B 《Nature》2007,449(7165):1053-1057
102.
点带石斑鱼仔、稚、幼鱼的形态观察 总被引:11,自引:1,他引:11
根据点带石斑鱼胚后发育过程中卵黄囊的消失、鳍的形成、鳞片的出现等形态特征变化 ,参照国内外对硬骨鱼类胚后发育时期划分的一般方法 ,将点带石斑鱼的胚后发育划分为仔鱼期 (含卵黄囊期仔鱼和后期仔鱼 )、稚鱼期、幼鱼期 ,并对各个发育时期的形态特征进行了较为详细的描述 ,记录了各个发育时期的体长、体重的增长情况 相似文献
103.
Aerosols implicated as a prime driver of twentieth-century North Atlantic climate variability 总被引:5,自引:0,他引:5
Systematic climate shifts have been linked to multidecadal variability in observed sea surface temperatures in the North Atlantic Ocean. These links are extensive, influencing a range of climate processes such as hurricane activity and African Sahel and Amazonian droughts. The variability is distinct from historical global-mean temperature changes and is commonly attributed to natural ocean oscillations. A number of studies have provided evidence that aerosols can influence long-term changes in sea surface temperatures, but climate models have so far failed to reproduce these interactions and the role of aerosols in decadal variability remains unclear. Here we use a state-of-the-art Earth system climate model to show that aerosol emissions and periods of volcanic activity explain 76 per cent of the simulated multidecadal variance in detrended 1860-2005 North Atlantic sea surface temperatures. After 1950, simulated variability is within observational estimates; our estimates for 1910-1940 capture twice the warming of previous generation models but do not explain the entire observed trend. Other processes, such as ocean circulation, may also have contributed to variability in the early twentieth century. Mechanistically, we find that inclusion of aerosol-cloud microphysical effects, which were included in few previous multimodel ensembles, dominates the magnitude (80 per cent) and the spatial pattern of the total surface aerosol forcing in the North Atlantic. Our findings suggest that anthropogenic aerosol emissions influenced a range of societally important historical climate events such as peaks in hurricane activity and Sahel drought. Decadal-scale model predictions of regional Atlantic climate will probably be improved by incorporating aerosol-cloud microphysical interactions and estimates of future concentrations of aerosols, emissions of which are directly addressable by policy actions. 相似文献
104.
高速宽间隔混沌序列跳频器的设计与实现 总被引:1,自引:0,他引:1
本文讨论了一种新型跳频器的设计方案,还通过DSP的实现证明了它在实践上的可行性和在性能上的优越性.该方案完成了跳频通信系统中极为重要的两个功能:伪随机码的产生和跳变频率的合成,并将它们有机地结合在一起. 相似文献
105.
106.
Russian Journal of Organic Chemistry - A green protocol has been developed for the preparation of 2,2′-(arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) following the... 相似文献
107.
Juechen Ni Yijia Wang Haoke Zhang Jing Zhi Sun Ben Zhong Tang 《Molecules (Basel, Switzerland)》2021,26(2)
Luminogens with aggregation-induced emission (AIEgens) have been widely applied in the field of photodynamic therapy. Among them, aggregation-induced emission photosensitizers (AIE–PSs) are demonstrated with high capability in fluorescence and photoacoustic bimodal imaging, as well as in fluorescence imaging-guided photodynamic therapy. They not only improve diagnosis accuracy but also provide an efficient theranostic platform to accelerate preclinical translation as well. In this short review, we divide AIE–PSs into three categories. Through the analysis of such classification and construction methods, it will be helpful for scientists to further develop various types of AIE–PSs with superior performance. 相似文献
108.
Amira Mahmoud Mosaab Echabaane Karim Omri Julien Boudon Lucien Saviot Nadine Millot Rafik Ben Chaabane 《Molecules (Basel, Switzerland)》2021,26(4)
Copper-doped zinc oxide nanoparticles (NPs) CuxZn1−xO (x = 0, 0.01, 0.02, 0.03, and 0.04) were synthesized via a sol-gel process and used as an active electrode material to fabricate a non-enzymatic electrochemical sensor for the detection of glucose. Their structure, composition, and chemical properties were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) and Raman spectroscopies, and zeta potential measurements. The electrochemical characterization of the sensors was studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). Cu doping was shown to improve the electrocatalytic activity for the oxidation of glucose, which resulted from the accelerated electron transfer and greatly improved electrochemical conductivity. The experimental conditions for the detection of glucose were optimized: a linear dependence between the glucose concentration and current intensity was established in the range from 1 nM to 100 μM with a limit of detection of 0.7 nM. The proposed sensor exhibited high selectivity for glucose in the presence of various interfering species. The developed sensor was also successfully tested for the detection of glucose in human serum samples. 相似文献
109.
Nahed N. E. El-Sayed Taghreed M. Al-Otaibi Mona Alonazi Vijay H. Masand Assem Barakat Zainab M. Almarhoon Abir Ben Bacha 《Molecules (Basel, Switzerland)》2021,26(11)
The pathogenesis of colorectal cancer is a multifactorial process. Dysbiosis and the overexpression of COX-2 and LDHA are important effectors in the initiation and development of the disease through chromosomal instability, PGE2 biosynthesis, and induction of the Warburg effect, respectively. Herein, we report the in vitro testing of some new quinoxalinone and quinazolinone Schiff’s bases as: antibacterial, COX-2 and LDHA inhibitors, and anticolorectal agents on HCT-116 and LoVo cells. Moreover, molecular docking and SAR analyses were performed to identify the structural features contributing to the biological activities. Among the synthesized molecules, the most active cytotoxic agent, (6d) was also a COX-2 inhibitor. In silico ADMET studies predicted that (6d) would have high Caco-2 permeability, and %HIA (99.58%), with low BBB permeability, zero hepatotoxicity, and zero risk of sudden cardiac arrest, or mutagenicity. Further, (6d) is not a potential P-gp substrate, instead, it is a possible P-gpI and II inhibitor, therefore, it can prevent or reverse the multidrug resistance of the anticancer drugs. Collectively, (6d) can be considered as a promising lead suitable for further optimization to develop anti-CRC agents or glycoproteins inhibitors. 相似文献
110.
Ben Abdelouahab N. Gossard A. Ma X. Dialla H. Maillet B. Rodts S. Coussot P. 《Cellulose (London, England)》2021,28(9):5321-5334
Cellulose - This study concerns the spatial evolution of the internal components of a macroscopic sample of cellulose slurry during its convective drying. In a first stage, some water is extracted... 相似文献