High-Contrast Visualization of Upconversion Luminescence in Mice Using Time-Gating Approach

An Nd3+-sensitized upconversion nanosystem was successfully used as a high-contrast nanoprobe for probing ClO− in living cells and as an in vivo mouse model of arthritis under 808 nm irradiation.

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Upconversion Luminescent NaYbF4: Er3+, Tm3+ Nanoparticles: Spectrally Pure and Intense near Infrared to near Infrared Emission

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.33.83 ◽

2015 ◽

Vol 33 ◽

pp. 83-91 ◽

Cited By ~ 2

Author(s):

Guo Zhang ◽

Rui Tao Chai ◽

Yu Chen ◽

She Ying Dong ◽

Liang Zhang ◽

...

Keyword(s):

Oleic Acid ◽

High Temperature ◽

Near Infrared ◽

Upconversion Luminescence ◽

Infrared Emission ◽

Spectral Purity ◽

High Contrast ◽

Near Infrared Emission

NaYbF4: Yb3+, Tm3+ nanoparticles (UCNPs) capped with oleic acid (OA) have been synthesized via high-temperature solvent reaction. The optimization sample of NaYb0.96Er0.02Tm0.02F4 nanoparticles possess spectral purity (the Snw value is bigger than 0.7) and intense near infrared to near infrared (NIR-to-NIR) upconversion luminescence (UCL) (the power of laser is as low as 3.8 W), which makes them ideal and promising platforms for high contrast bioimaging.

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Afterglow Nanoparticles: Coloring Afterglow Nanoparticles for High‐Contrast Time‐Gating‐Free Multiplex Luminescence Imaging (Adv. Mater. 49/2020)

Advanced Materials ◽

10.1002/adma.202070371 ◽

2020 ◽

Vol 32 (49) ◽

pp. 2070371

Author(s):

Zhanjun Li ◽

Nuo Yu ◽

Juanjuan Zhou ◽

Yang Li ◽

Yuanwei Zhang ◽

...

Keyword(s):

High Contrast ◽

Luminescence Imaging ◽

Time Gating

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High Contrast Upconversion Luminescence Targeted Imaging in Vivo Using Peptide-Labeled Nanophosphors

Analytical Chemistry ◽

10.1021/ac901960d ◽

2009 ◽

Vol 81 (21) ◽

pp. 8687-8694 ◽

Cited By ~ 320

Author(s):

Liqin Xiong ◽

Zhigang Chen ◽

Qiwei Tian ◽

Tianye Cao ◽

Congjian Xu ◽

...

Keyword(s):

Upconversion Luminescence ◽

Targeted Imaging ◽

High Contrast

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Removing the Obstacle of Dye‐Sensitized Upconversion Luminescence in Aqueous Phase to Achieve High‐Contrast Deep Imaging In Vivo

Advanced Functional Materials ◽

10.1002/adfm.201910765 ◽

2020 ◽

Vol 30 (16) ◽

pp. 1910765 ◽

Cited By ~ 3

Author(s):

Tao Liang ◽

Qirong Wang ◽

Zhen Li ◽

Peipei Wang ◽

Junjie Wu ◽

...

Keyword(s):

Aqueous Phase ◽

Upconversion Luminescence ◽

High Contrast ◽

Dye Sensitized ◽

Deep Imaging

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Resistance Monitor and Control for Vacuum Evaporation of Metals and Carbon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092827 ◽

1976 ◽

Vol 34 ◽

pp. 572-573

Author(s):

Russell L. Steere ◽

Eric F. Erbe ◽

J. Michael Moseley

Keyword(s):

Electronic Device ◽

Point Sources ◽

High Contrast ◽

Variable Resistor ◽

Quality Of Results ◽

Low Contrast ◽

Evaporation Source ◽

And Control ◽

At Will

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.

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Confocal laser microscopy of impregnated central nervous system tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102559 ◽

1988 ◽

Vol 46 ◽

pp. 94-95

Author(s):

J.N. Turner ◽

M. Siemens ◽

D. Szarowski ◽

D.N. Collins

Keyword(s):

Electron Microscopy ◽

Central Nervous System ◽

Nervous System ◽

Three Dimensional ◽

Dimensional Structure ◽

Confocal Laser ◽

High Contrast ◽

Central Nervous System Tissue ◽

Tissue Samples ◽

Reflected Light

A classic preparation of central nervous system tissue (CNS) is the Golgi procedure popularized by Cajal. The method is partially specific as only a few cells are impregnated with silver chromate usualy after osmium post fixation. Samples are observable by light (LM) or electron microscopy (EM). However, the impregnation is often so dense that structures are masked in EM, and the osmium background may be undesirable in LM. Gold toning is used for a subtle but high contrast EM preparation, and osmium can be omitted for LM. We are investigating these preparations as part of a study to develop correlative LM and EM (particularly HVEM) methodologies in neurobiology. Confocal light microscopy is particularly useful as the impregnated cells have extensive three-dimensional structure in tissue samples from one to several hundred micrometers thick. Boyde has observed similar preparations in the tandem scanning reflected light microscope (TSRLM).

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The CM120 Biotwin: a high-contrast objective lens, optimum cryo-vacuum and improved EDX performance

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139299 ◽

1995 ◽

Vol 53 ◽

pp. 584-585

Author(s):

Uwe Lücken ◽

Michael Felsmann ◽

Wim M. Busing ◽

Frank de Jong

Keyword(s):

Life Science ◽

Focal Length ◽

Objective Lens ◽

High Contrast ◽

Contrast Imaging ◽

X Ray ◽

Forming Mechanism ◽

Similar Image ◽

High Contrast Imaging ◽

Low Concentrations

A new microscope for the study of life science specimen has been developed. Special attention has been given to the problems of unstained samples, cryo-specimens and x-ray analysis at low concentrations.A new objective lens with a Cs of 6.2 mm and a focal length of 5.9 mm for high-contrast imaging has been developed. The contrast of a TWIN lens (f = 2.8 mm, Cs = 2 mm) and the BioTWTN are compared at the level of mean and SD of slow scan CCD images. Figure 1a shows 500 +/- 150 and Fig. 1b only 500 +/- 40 counts/pixel. The contrast-forming mechanism for amplitude contrast is dependent on the wavelength, the objective aperture and the focal length. For similar image conditions (same voltage, same objective aperture) the BioTWIN shows more than double the contrast of the TWIN lens. For phasecontrast specimens (like thin frozen-hydrated films) the contrast at Scherzer focus is approximately proportional to the √ Cs.

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Performance and applications of the holography electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151222 ◽

1993 ◽

Vol 51 ◽

pp. 1078-1079

Author(s):

Akira Tonomura

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Phase Measurement ◽

Electron Holography ◽

Imaging Method ◽

High Contrast ◽

Magnetic Lens ◽

High Brightness ◽

Holographic Imaging ◽

Dynamic Observation

Electron holography is a two-step imaging method. However, the ultimate performance of holographic imaging is mainly determined by the brightness of the electron beam used in the hologram-formation process. In our 350kV holography electron microscope (see Fig. 1), the decrease in the inherently high brightness of field-emitted electrons is minimized by superposing a magnetic lens in the gun, for a resulting value of 2 × 109 A/cm2 sr. This high brightness has lead to the following distinguished features. The minimum spacing (d) of carrier fringes is d = 0.09 Å, thus allowing a reconstructed image with a resolution, at least in principle, as high as 3d=0.3 Å. The precision in phase measurement can be as high as 2π/100, since the position of fringes can be known precisely from a high-contrast hologram formed under highly collimated illumination. Dynamic observation becomes possible because the current density is high.

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