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1.
一种用于盐度测量的光纤传感器   总被引:3,自引:0,他引:3  
制作了智能水凝胶PDA—C12。根据凝胶的溶胀性质设计制作了一种盐度光纤传感器探头,并实测了在不同盐度溶液中的输出光强,可测范围达到了1.0mol/L以上,为在一般要求下的盐度测量提供了一种新的方法。  相似文献   

2.
研究证明,传统膜片钳放大器在电流钳模式下记录到的快速电压信号会存在失真,且造成失真的根本原因是由于膜片钳的探头电路设计.为了克服这些缺陷重新设计了一种探头,新探头电路不仅能像传统的电压跟随器一样测量瞬态电压,而且适用于传统的电压钳工作模式.此外,一种命名为电压钳控制的电流钳技术被应用来改进传统的膜片钳放大器.用可变的低通滤波器来调整电压钳模块的响应速度,从而在实现膜电位钳位的同时准确记录快速电压信号.桥平衡电路用来消除命令电流流过串联电阻时带来的电压误差.而传统膜片钳中的快电容补偿环节则被改进用来补偿电极分布电容和探头放大器输入电容并提高电流钳模式下系统的响应速度.细胞模型实验结果表明,改进后的膜片钳放大器能够满足电生理研究中快速电位变化测量的需要.  相似文献   

3.
近年来,许多研究人员不断努力为药物、除草剂、食品添加剂等小分子物质高特异性、高灵敏的检测和分析开发新的方法和技术。然而,目前通用的分子检测方法的实施需要较长的前处理时间、昂贵的大型仪器设备及专业操作人员,无法实现有选择的识别及快速的现场检测。所以,在本研究中我们将量子点表面分子印迹聚合物(QDs@MIPs)与光纤相结合,构建了一种新的光纤探头,并将该光纤探头应用于光纤传感器,检测小分子物质莱克多巴胺(RAC)。试验中,我们对QDs@MIPs的表征、光纤探头的性能、光纤探头对RAC的浓度响应、光纤传感器的特异性及光强分布进行了探究。研究结果表明,该光纤探头应用于光纤传感器能够提高光纤传感器的灵敏度,使分子印迹光纤传感器具有更高的特异性识别能力和较强的抗干扰能力,同时检测过程简便快捷,适用于快速的现场检测。  相似文献   

4.
杜梦鸽  王胜  樊军 《生态学杂志》2017,28(8):2438-2444
准确测量树干液流对研究树木耗水特性、植物生理和生态水文效应等具有重要意义.本文选用一种新型五针热脉冲多功能数字探头(PHPP),运用热脉冲理论,测量小叶杨树干液流,并与热扩散探针(TDP)进行对比分析,探究五针热脉冲探头测量树干液流的适用性和准确性.结果表明: 五针热脉冲探头能够准确揭示小叶杨树干液流昼夜变化规律,并且与热扩散探针测量结果呈显著的线性相关关系,R2达到0.90,均方根误差为2.75,平均相对误差为11%.PHPP探头能较为精确地识别低液流和逆液流,可以快速准确地拟合热参数,直接测得树干液流速率,应用潜力较大.  相似文献   

5.
278、肛管超声检查(Anal endosonography) 本法是应用超声直肠探头,频率为5~7MHz。探头为旋转式,其外装有硬质塑料圆锥,直径2cm,在其内可注水排气,用以保护探头。患者左侧卧位,检查前排空大便,无需肠道准备,将此探头润滑后插入直肠,在缓慢退出过程中,作不同平面的360°扫描。 肛管超声的临床应用价值在于:  相似文献   

6.
陈郁初 《生命科学》2001,13(4):189-192
介绍了一种新颖的在位实时监测脑内化学物质变化的新方法,在探头-透析电极制作中运用了酶化学,电化学和微透析技术,能连续测定行为动物脑人神经化学物质浓度的变化,并且不需要借助高效液相仪作测定^[1],同时,扼要地介绍了探头的结构以及该技术的应用。  相似文献   

7.
家兔胃运动的慢性记录方法   总被引:14,自引:0,他引:14  
本文介绍了应用霍耳效应原理、借助特殊的胃探头固定装置,记录家兔胃运动的方法。 在胃探头固定装置上安装引导电极,可同时记录胃电变化。本记录方法根据磁块移动距离与电压变化的函数关系,可由测得的电压变化数值,计算出胃平滑肌收缩时移动的距离,并能较好的消除呼吸波,具有较强的抗干扰能力。  相似文献   

8.
光学相干层析用于牙齿病变的检测   总被引:3,自引:0,他引:3  
阐述了适用于牙齿结构成像的光学相干层析成像(OCT)系统。系统光源中心波长为1 310 nm,成像分辨率10μm,在牙内成像深度2 mm,成像速度1幅/秒,系统信噪比100 dB。利用此OCT仪清晰检测到牙齿样品的牙釉质和牙本质,观察到牙釉质与牙本质的分界面以及正常牙齿牙釉质与龋齿牙齿牙釉质OCT图像的区别。进一步设计研制了适用于口腔内探测的小型OCT探头。  相似文献   

9.
日本前川制作所与东北大学流体科学研究所联合开发研制成体内治疗用低温探头(极低温定点冷却装置)。其直径只有2.6毫米,长为1米。与早先的产品相比,该探头又细又长,所以能够装在胃镜中,并在胃的肿瘤部分上喷射极低温的液体,使患部冷冻并坏死。这样,患者可免开腹手术而定期进行治疗。它是世界上第一台能直接在人体内进行极低温定点治疗的装置。该装置由三层管子构成。通过内管将-196℃的液氮送到管的前端,使前端上的治疗头冷却。液氮通过中管与内管之间的环形部喷出。由于在外管和中管外层间有超薄型的特殊隔热构造,所以除前端以外,能够维持接近常温的状态。早先的低温探头的冷却头,直径为10毫米,长度为30厘米。而新装置包含隔热层在  相似文献   

10.
沈丽敏  陈郁初 《生命科学》1999,11(3):137-139,134
应用透析原理对脑内细胞外液中神经化学物质进行取样分析的想法已有20多年历史,对脑内细胞外液进行分析可以更好地了解中枢神经系统的生理和病理情况,而微透析技术就是一种用来测定脑内细胞外液神经递质浓度的取样方法,随着探头设计的微型化和高灵敏度的分析方法的建立,微透析技术在许多实验室已成为一种常规实验手段,近年来,以猴脑的研究对象的微透析实验呈增长趋势,并获得了一些崭新的结果,本文介绍在猴脑上进行微透技术  相似文献   

11.
Probes are the interface between microsystems and bio-cells.The ideal interface is one-to-one interface.Though variousresearch groups have been able to establish some sort of interfaces after many years of research,they are very crude.Neurons aremillions in numbers,whereas the prostheses successfully built so far have only a few hundred probes at best.Creating an ef-fective interface is still far away.Though we have micro-and nano-technologies,we couldn’t build a prosthesis with an effectiveresolution.Main reasons behind it are the type of probe being used and the poor design of the probe.To address this problem,wedeveloped a methodology to design a probe and an array of probes with better resolution and less resistive donut probe.Thismethodology helps us to design a probe optimizing all the parameters.We presented our methodology through a design that iscapable of 70 μm penetration inside the tissue.The tissue heating by our designed probe is only 0.411 °C.We also characterizedthe donut probe,which could be used by any research group to design a donut probe of their specific need.  相似文献   

12.
Most current microarray oligonucleotide probe design strategies are based on probe design factors (PDFs), which include probe hybridization free energy (PHFE), probe minimum folding energy (PMFE), dimer score, hairpin score, homology score and complexity score. The impact of these PDFs on probe performance was evaluated using four sets of microarray comparative genome hybridization (aCGH) data, which included two array manufacturing methods and the genomes of two species. Since most of the hybridizing DNA is equimolar in CGH data, such data are ideal for testing the general hybridization properties of almost all candidate oligonucleotides. In all our data sets, PDFs related to probe secondary structure (PMFE, hairpin score and dimer score) are the most significant factors linearly correlated with probe hybridization intensities. PHFE, homology and complexity score are correlating significantly with probe specificities, but in a non-linear fashion. We developed a new PDF, pseudo probe binding energy (PPBE), by iteratively fitting dinucleotide positional weights and dinucleotide stacking energies until the average residue sum of squares for the model was minimized. PPBE showed a better correlation with probe sensitivity and a better specificity than all other PDFs, although training data are required to construct a PPBE model prior to designing new oligonucleotide probes. The physical properties that are measured by PPBE are as yet unknown but include a platform-dependent component. A practical way to use these PDFs for probe design is to set cutoff thresholds to filter out bad quality probes. Programs and correlation parameters from this study are freely available to facilitate the design of DNA microarray oligonucleotide probes.  相似文献   

13.
随着16 S rRNA序列资源的不断丰富,以及寡核苷酸微阵列基因芯片技术的不断进步,检测复杂微生物菌落中的微生物种群构成成为可能.现有的序列特异性探针设计算法缺乏足够的覆盖度、灵活性以及效率,不能满足大规模细菌检测基因芯片的设计要求.很多组特异性探针设计算法的思路多局限于针对某个目标序列组设计唯一的组特异性探针.在很多应用场合,设计单个探针检测组内所有目标序列的目标是很难达到的.因此,设计多个探针通过组合方式进行检测是很有必要的.每个探针能特异性地检测组内一部分目标序列,通过组合就能提高覆盖率.然而,在所有可能的探针组合中找到一个优化的探针组合是很耗时的.提出了一个可行的基于相对熵和遗传算法的组合探针设计算法.  相似文献   

14.
MProbe: computer aided probe design for oligonucleotide microarrays   总被引:1,自引:0,他引:1  
The present work describes a complete probe design software system for oligonucleotide microarrays based on Kane's research on probe sensitivity and specificity (Kane's rule). Combining Kane's rule and traditional criteria for probe design we constructed MProbe, the software system for oligonucleotide microarrays using Java. The general criteria for probe design are: (1) probes may have different lengths that range from 20 to 100 bases; (2) they should have a similar melting temperature (Tm) or GC content; (3) they should not contain stable secondary structures; and (4) they abide by Kane's rule.  相似文献   

15.
Targeted capture and enrichment approaches have proven effective for phylogenetic study. Ultraconserved elements (UCEs) in particular have exhibited great utility for phylogenomic analyses, with the software package phyluce being among the most utilized pipelines for UCE phylogenomics, including probe design. Despite the success of UCEs, it is becoming increasing apparent that diverse lineages require probe sets tailored to focal taxa in order to improve locus recovery. However, factors affecting probe design and methods for optimizing probe sets to focal taxa remain underexplored. Here, we use newly available beetle (Coleoptera) genomic resources to investigate factors affecting UCE probe set design using phyluce . In particular, we explore the effects of stringency during initial design steps, as well as base genome choice on resulting probe sets and locus recovery. We found that both base genome choice and initial bait design stringency parameters greatly alter the number of resultant probes included in final probe sets and strongly affect the number of loci detected and recovered during in silico testing of these probe sets. In addition, we identify attributes of base genomes that correlated with high performance in probe design. Ultimately, we provide a recommended workflow for using Phyluce to design an optimized UCE probe set that will work across a targeted lineage, and use our findings to develop a new, open‐source UCE probe set for beetles of the suborder Adephaga.  相似文献   

16.
DNA-based microarrays are increasingly central to biomedical research. Selecting oligonucleotide sequences that will behave consistently across experiments is essential to the design, production and performance of DNA microarrays. Here our aim was to improve on probe design parameters by empirically and systematically evaluating probe performance in a multivariate context. We used experimental data from 19 array CGH hybridizations to assess the probe performance of 385,474 probes tiled in the Duchenne muscular dystrophy (DMD) region of the X chromosome. Our results demonstrate that probe melting temperature, single nucleotide polymorphisms (SNPs), and homocytosine motifs all have a strong effect on probe behavior. These findings, when incorporated into future microarray probe selection algorithms, may improve microarray performance for a wide variety of applications.  相似文献   

17.
Flexible probes that are safely deployed to hard-to-reach targets while avoiding critical structures are strategic in several high-impact application fields, including the biomedical sector and the sector of inspections at large. A critical problem for these tools is the best approach for deploying an entire tool body, not only its tip, on a sought trajectory. A probe that achieves this deployment is considered to follow the leader (or to achieve follow-the-leader deployment) because its body sections follow the track traced by its tip. Follow-the-leader deployment through cavities is complicated due to a lack of external supports. Currently, no definitive implementation for a probe that is intrinsically able to follow the leader, i.e., without relying on external supports, has been achieved. In this paper, we present a completely new device, namely the first interlaced continuum robot, devised to intrinsically follow the leader. We developed the interlaced configuration by pursuing a conceptual approach irrespective of application-specific constraints and assuming two flexible tools with controllable stiffness. We questioned the possibility of solving the previously mentioned deployment problem by harnessing probe symmetry during the design process. This study examines the entire development of the novel interlaced probe: model-based conceptual design, detailed design and prototyping, and preliminary experimental assessment. Our probe can build a track with a radius of curvature that is as small as twice the probe diameter, which enables it to outperform state-of-the-art tools that are aimed at follow-the-leader deployment. Despite the limitations that are inherently associated with its original character, this study provides a prototypical approach to the design of interlaced continuum systems and demonstrates the first interlaced continuum probe, which is intrinsically able to follow the leader.  相似文献   

18.
探针设计是SARS病毒再测序DNA微阵列制作的关键步骤,为了保证探针的杂交条件尽可能一致,采用了作者提出的两种等长变覆盖的探针设计方法,即基于Tm距离的算法和遗传算法。针对SAILS病毒基因组中的两段特异序列设计了一组探针,并与等长移位法和变长变覆盖法的设计结果进行了比较。等长变覆盖法得到的探针集在探针长度一致的情况下,探针的Tm值有较小的标准差和变化范围。结果表明,等长变覆盖法得到的探针具有更好的杂交条件一致性。  相似文献   

19.
A major challenge in microarray design is the selection of highly specific oligonucleotide probes for all targeted genes of interest, while maintaining thermodynamic uniformity at the hybridization temperature. We introduce a novel microarray design framework (Thermodynamic Model-based Oligo Design Optimizer, TherMODO) that for the first time incorporates a number of advanced modelling features: (i) A model of position-dependent labelling effects that is quantitatively derived from experiment. (ii) Multi-state thermodynamic hybridization models of probe binding behaviour, including potential cross-hybridization reactions. (iii) A fast calibrated sequence-similarity-based heuristic for cross-hybridization prediction supporting large-scale designs. (iv) A novel compound score formulation for the integrated assessment of multiple probe design objectives. In contrast to a greedy search for probes meeting parameter thresholds, this approach permits an optimization at the probe set level and facilitates the selection of highly specific probe candidates while maintaining probe set uniformity. (v) Lastly, a flexible target grouping structure allows easy adaptation of the pipeline to a variety of microarray application scenarios. The algorithm and features are discussed and demonstrated on actual design runs. Source code is available on request.  相似文献   

20.
A probe for the extraction of soil gases is described. Novel features are the way the probe aperture within the soil can be manipulated from above, and the design of the tip to maximize gas extraction.  相似文献   

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