AMBER: optical design and expected performance

Picosecond and femtosecond streak cameras: present and future designs

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1980.0252 ◽

1980 ◽

Vol 298 (1439) ◽

pp. 281-285 ◽

Cited By ~ 5

Keyword(s):

Time Resolution ◽

Time Domain ◽

Optical Design ◽

Preliminary Design ◽

X Ray ◽

Time Dispersion ◽

Expected Performance ◽

Experimental Values ◽

Imaging Properties ◽

Streak Tube

For many applications of time-domain spectroscopy it is desirable to improve the time resolution of electron-optical streak cameras to less than 200 fs in the u.v. visible and i.r. and to ca . 1 ps at X-ray wavelengths. A suite of interactive computer programs has been developed for electron-optical design, taking into account time dispersion. It is possible to analyse rapidly the details of both spatial and temporal imaging properties of currently available streak tubes and to optimize the designs for particular applications. The computed results are shown to be in excellent agreement with the experimental values for the Photochron II streak tube. The expected performance characteristics of a preliminary design for a new tube, the Photochron III, are given.

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Liquid mirrors

Canadian Journal of Physics ◽

10.1139/p95-017 ◽

1995 ◽

Vol 73 (3-4) ◽

pp. 109-125 ◽

Cited By ~ 14

Author(s):

Ermanno F. Borra

Keyword(s):

Optical Design ◽

Wide Band ◽

Scientific Work ◽

Optical Quality ◽

Full Time ◽

Design Work ◽

Atmospheric Sciences ◽

Expected Performance ◽

Basic Technology ◽

Liquid Mirrors

The surface of a spinning liquid takes the shape of a paraboloid that can be used as a reflecting mirror. This very old and nearly forgotten concept has recently been revived and I review its present status. Extensive interferometric tests of liquid mirrors (the largest one having a diameter of 2.5 m) show excellent optical qualities. I discuss the factors that can limit the optical quality of liquid mirrors, how to minimize them as well as the basic technology. A handful of liquid mirrors have now been built that are used for scientific work. I show representative data obtained from 2.65 m diameter liquid mirror telescopes used for astronomy and the atmospheric sciences (LIDAR). Section 5, of particular interest to cosmologists or astronomers using surveys, examines the expected performance of 4 m liquid mirror telescopes (LMTs) dedicated to cosmological surveys. It is rather impressive, due to the fact that the instruments work full-time on 4 year surveys: Spectrophotometry reaches B = 24 for all objects within over 100 square degrees and wide-band photometry reaches about B = 28. I consider the future of liquid mirror telescopes: limits to their sizes, engineering issues, as well as speculations on lunar or space LMTs. I briefly mention the possibility of nonrotating GRIN (gradient index) liquid mirrors. Finally, I address the issues of the field accessible to LMTs equipped with novel optical correctors. Optical design work, and some exploratory laboratory work, indicate that a single LMT should be able to access, with excellent images, small regions anywhere inside fields as large as 45°.

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Use of the Magnetostatic Analogue In Electromagnetic Lens Engineering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068795 ◽

1970 ◽

Vol 28 ◽

pp. 360-361

Author(s):

John W. Coleman

Keyword(s):

Boundary Conditions ◽

High Performance ◽

Force Fields ◽

Optical Design ◽

Direct Conversion ◽

Design Engineering ◽

Design Data ◽

Scalar Potentials ◽

Geometric Elements ◽

At Will

In the design engineering of high performance electromagnetic lenses, the direct conversion of electron optical design data into drawings for reliable hardware is oftentimes difficult, especially in terms of how to mount parts to each other, how to tolerance dimensions, and how to specify finishes. An answer to this is in the use of magnetostatic analytics, corresponding to boundary conditions for the optical design. With such models, the magnetostatic force on a test pole along the axis may be examined, and in this way one may obtain priority listings for holding dimensions, relieving stresses, etc..The development of magnetostatic models most easily proceeds from the derivation of scalar potentials of separate geometric elements. These potentials can then be conbined at will because of the superposition characteristic of conservative force fields.

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The miR-21 potential of serving as a biomarker for liver diseases in clinical practice

Biochemical Society Transactions ◽

10.1042/bst20200653 ◽

2020 ◽

Vol 48 (5) ◽

pp. 2295-2305

Author(s):

Jiawei Zhang ◽

Dandan Li ◽

Rui Zhang ◽

Peng Gao ◽

Rongxue Peng ◽

...

Keyword(s):

Clinical Practice ◽

Liver Diseases ◽

Hepatic Disease ◽

Noninvasive Detection ◽

Diagnosis And Prognosis ◽

Expected Performance ◽

Potential Biomarker ◽

Disease Condition ◽

Complex Regulatory Network

The role of miR-21 in the pathogenesis of various liver diseases, together with the possibility of detecting microRNA in the circulation, makes miR-21 a potential biomarker for noninvasive detection. In this review, we summarize the potential utility of extracellular miR-21 in the clinical management of hepatic disease patients and compared it with the current clinical practice. MiR-21 shows screening and prognostic value for liver cancer. In liver cirrhosis, miR-21 may serve as a biomarker for the differentiating diagnosis and prognosis. MiR-21 is also a potential biomarker for the severity of hepatitis. We elucidate the disease condition under which miR-21 testing can reach the expected performance. Though miR-21 is a key regulator of liver diseases, microRNAs coordinate with each other in the complex regulatory network. As a result, the performance of miR-21 is better when combined with other microRNAs or classical biomarkers under certain clinical circumstances.

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