Carbon-mixed dental cement for fixing fiber optic ferrules prevents visually triggered locomotive enhancement in mice upon optogenetic stimulation

Some of the most important applications of STEM depend on the variety of imaging and diffraction made possible by the versatility of the detector system and the serial nature, of the image acquisition. A special detector system, previously described, has been added to our STEM instrument to allow us to take full advantage of this versatility. In this, the diffraction pattern in the detector plane may be formed on either of two phosphor screens, one with P47 (very fast) phosphor and the other with P20 (high efficiency) phosphor. The light from the phosphor is conveyed through a fiber-optic rod to an image intensifier and TV system and may be photographed, recorded on videotape, or stored digitally on a frame store. The P47 screen has a hole through it to allow electrons to enter a Gatan EELS spectrometer. Recently a modified SEM detector has been added so that high resolution (10Å) imaging with secondary electrons may be used in conjunction with other modes.

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Synthesis, performance and growth mechanism of silver nanoparticle coated SERS fiber probe

Matériaux & Techniques ◽

10.1051/mattech/2018061 ◽

2019 ◽

Vol 107 (3) ◽

pp. 305

Author(s):

Mengmei Geng ◽

Yuting Long ◽

Tongqing Liu ◽

Zijuan Du ◽

Hong Li ◽

...

Keyword(s):

Silver Nanoparticles ◽

Absorption Spectrum ◽

Reaction Time ◽

Growth Mechanism ◽

Fiber Optic ◽

Fiber Optic Probe ◽

Visible Absorption ◽

Fiber Probe ◽

Surface Enhanced Raman ◽

Optic Probe

Surface-enhanced Raman Scattering (SERS) fiber probe provides abundant interaction area between light and materials, permits detection within limited space and is especially useful for remote or in situ detection. A silver decorated SERS fiber optic probe was prepared by hydrothermal method. This method manages to accomplish the growth of silver nanoparticles and its adherence on fiber optic tip within one step, simplifying the synthetic procedure. The effects of reaction time on phase composition, surface plasmon resonance property and morphology were investigated by X-ray diffraction analysis (XRD), ultraviolet-visible absorption spectrum (UV-VIS absorption spectrum) and scanning electron microscope (SEM). The results showed that when reaction time is prolonged from 4–8 hours at 180 °C, crystals size and size distribution of silver nanoparticles increase. Furthermore, the morphology, crystal size and distribution density of silver nanoparticles evolve along with reaction time. A growth mechanism based on two factors, equilibrium between nucleation and growth, and the existence of PVP, is hypothesized. The SERS fiber probe can detect rhodamin 6G (R6G) at the concentration of 10−6 M. This SERS fiber probe exhibits promising potential in organic dye and pesticide residue detection.

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Fast and Reproducible Vascular Neointima Formation in the Hamster Carotid Artery: Effects of Trapidil and Captopril

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649987 ◽

1995 ◽

Vol 74 (06) ◽

pp. 1591-1596 ◽

Cited By ~ 14

Author(s):

H Matsuno ◽

J M Stassen ◽

M F Hoylaerts ◽

J Vermylen ◽

H Deckmyn

Keyword(s):

Carotid Artery ◽

Enzyme Inhibitor ◽

Neointima Formation ◽

Proliferating Cells ◽

Dental Cement ◽

Proliferation Indices ◽

Experimental Drugs ◽

The Media ◽

Von Willebrand ◽

Willebrand Factor

SummaryNeointima formation was induced in the hamster carotid artery by mechanical intraluminal injury with a catheter covered with roughened dental cement. Neointimal thickening occurred as early as 7 days after denudation and further increased during the next 1 to 2 weeks. Proliferation indices of smooth muscle cells (SMCs) showed the highest proportion of proliferating cells in the media and neointima respectively 1 and 5 days after the vascular injury. Transmission and scanning electron microscopy of damaged carotid artery sections as well as immuno-histochemical stainings of von Willebrand factor (vWF) confirmed that reendothelialization was progressive and already complete on day 14, at which time the neointima formation was almost complete.In order to pharmacologically characterize this model further, the effects on neointima formation of trapidil (triazolopyrimidine), a platelet-derived growth factor (PDGF) antagonist, and captopril, an angiotensin converting enzyme inhibitor, were investigated. Trapidil administered orally twice daily at total doses of 25, 50 and 100 mg/kg/day, started 3 days prior to infliction of injury and up to 7 or 14 days after the catheterization, significantly reduced neointima formation. Captopril administered orally three times daily at a total dose of 100 mg/kg/day, equally reduced neointima formation, with 100 mg/kg/day trapidil being more effective than 100 mg/kg/day captopril 7 days after injury. When the treatment by either one of these drugs was arrested on day 7, neointima formation resumed quickly.The hamster appears to be a small, reproducible and fast model for the study of SMC proliferation, requiring only relatively small amounts of experimental drugs. The model furthermore is sensitive to substances known to reduce neointima formation in other animal models.

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Performance Monitoring of Extreme Large-Diameter Prestressed Concrete Cylinder Pipe with Distributed Fiber Optic Sensors

Pipelines 2016 ◽

10.1061/9780784479957.051 ◽

2016 ◽

Cited By ~ 1

Author(s):

Xin Feng ◽

Wenjing Wu ◽

Sheng Zhong ◽

Tong Zhu ◽

Jing Zhou

Keyword(s):

Prestressed Concrete ◽

Performance Monitoring ◽

Fiber Optic ◽

Large Diameter ◽

Fiber Optic Sensors ◽

Concrete Cylinder ◽

Prestressed Concrete Cylinder Pipe

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Increasing the information capacity of a fiber-optic multi-sensor converter of binary mechanical signals into electrical signals

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-9-15-23 ◽

2020 ◽

pp. 15-23

Author(s):

V. M. Grechishnikov ◽

E. G. Komarov

Keyword(s):

Fiber Optic ◽

Information Capacity ◽

Parallel Structure ◽

Optical Scheme ◽

Digital To Analog Converter ◽

Electrical Signals ◽

Mechanical Signals ◽

Analog Converter ◽

Output Code ◽

Digital To Analog

The design and operation principle of a multi-sensor Converter of binary mechanical signals into electrical signals based on a partitioned fiber-optic digital-to-analog Converter with a parallel structure is considered. The digital-to-analog Converter is made from a set of simple and technological (three to five digit) fiber-optic digital-to-analog sections. The advantages of the optical scheme of the proposed. Converter in terms of metrological and energy characteristics in comparison with single multi-bit converters are justified. It is shown that by increasing the number of digital-analog sections, it is possible to repeatedly increase the information capacity of a multi-sensor Converter without tightening the requirements for its manufacturing technology and element base. A mathematical model of the proposed Converter is developed that reflects the features of its operation in the mode of sequential time conversion of the input code vectors of individual fiber-optic sections into electrical analogues and the formation of the resulting output code vector.

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Hydrostatic Fiber Optic Liquid Level Sensor with position sensitive detector

Metrologiya ◽

10.32446/0132-4713.2020-4-38-51 ◽

2020 ◽

pp. 38-51

Author(s):

V. N. Astapov ◽

I. N. Kozlova

Keyword(s):

Fiber Optic ◽

Effective Area ◽

Raw Material ◽

Position Sensitive Detector ◽

Fiber Optic Sensor ◽

Liquid Level ◽

Problem Solution ◽

Sensitive Detector ◽

Position Sensitive ◽

Triangulation Sensor

This article presents the rationale and methodology for developing an intrinsically safe device, namely, a hydrostatic fiber optic sensor with a position-sensitive detector for monitoring the level of oil products in large-capacity tanks at oil depots and during pumping in a raw material warehouses. This device suitable for continuous monitoring of the liquid level, based on the measurement of a hydrostatic column of liquid with automatic offset of changes in the density of the liquid. Offset is carried out by means of a displacer (a fully submerged float), inside which a housing with a position-sensitive detector (PSD) is integrated. Theoretical validation of the bellows suspension usage for a displacer is given. During filling a container with a liquid whose level is measured, liquid bellows, the movement of which is recorded by an optical triangulation sensor using the reflected infrared ray incident on the bottom of the bellows. The principle of the triangulation sensor operation is based on the geometric properties of the triangles. The pulses of infrared radiation come through a fiber optic cable. In order to measure the movement of the surface (the bottom of the bellows) by measuring the movement of the reflected beam, a position-sensitive detector is used, which is located in a remote controller. In this device for the intrinsic safety problem solution, optical inputs of a fiber optic flat cable are located in the active zone of the sensor, which is connected to the optical inputs of a position-sensitive detector, operated on the principles of photoelectric effect. The light spot moving along the sensitive zone and converted by the detector into a one-dimensional signal proportional to the distance to the object. hydrostatically applies pressure over the entire effective area of the measuring

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