442,363 research outputs found

    James Annesley of Madras Medical Service (1800-1838) on cholera in Madras Presidency in 1825

    Get PDF
    James Annesley from Ireland spent nearly four decades in Madras, first as an assistant and later as a senior surgeon attached to the Madras Medical Establishment. During this span of service he published the book in 1825 on the most prevalent diseases of India comprising a treatise on the epidemic cholera of the East. This paper recounts the epidemiology of cholera and the efforts made to manage it in the Madras Presidency in the 1820s, keeping in view the life of Annesley and the contents of his book

    PDF/A-3u as an archival format for Accessible mathematics

    Full text link
    Including LaTeX source of mathematical expressions, within the PDF document of a text-book or research paper, has definite benefits regarding `Accessibility' considerations. Here we describe three ways in which this can be done, fully compatibly with international standards ISO 32000, ISO 19005-3, and the forthcoming ISO 32000-2 (PDF 2.0). Two methods use embedded files, also known as `attachments', holding information in either LaTeX or MathML formats, but use different PDF structures to relate these attachments to regions of the document window. One uses structure, so is applicable to a fully `Tagged PDF' context, while the other uses /AF tagging of the relevant content. The third method requires no tagging at all, instead including the source coding as the /ActualText replacement of a so-called `fake space'. Information provided this way is extracted via simple Select/Copy/Paste actions, and is available to existing screen-reading software and assistive technologies.Comment: This is a post-print version of original in volume: S.M. Watt et al. (Eds.): CICM 2014, LNAI 8543, pp.184-199, 2014; available at http://link.springer.com/search?query=LNAI+8543, along with supplementary PDF. This version, with supplement as attachment, is enriched to validate as PDF/A-3u modulo an error in white-space handling in the pdfTeX version used to generate i

    A new Raman technique of superior spectral resolution

    Get PDF
    Raman-active vibrational modes are coherently excited by the transient stimulated Raman process. A subsequent delayed probe of relatively long duration interacts with the freely relaxing vibrations. Raman spectra are generated with higher resolution and more accurate peak positions than in conventional Raman spectroscopy. In liquid cyclohexane four new Raman lines were readily detected in the frequency range 2870–2920 cm−1

    Horizon Tunneling Revisited: The Case of Higher Dimensional Black Holes

    Full text link
    We study the tunneling of massless scalars across black hole horizons in any number of spacetime dimensions greater than three. Our analysis finds that corrections due to backreaction and the inverse dimensional expansion are naturally concomitant, and furnishes a simple proof of the classic relation between entropy and area in all spacetime dimensions, finite or infinite. We conclude with a discussion of the limit in which the the number of spacetime dimensions is taken to infinity, where we find that thermodynamic quantities are related to the "thickness" of the membrane on which all the curvature is localized.Comment: 22 page

    Time-Encoded Raman: Fiber-based, hyperspectral, broadband stimulated Raman microscopy

    Get PDF
    Raman sensing and Raman microscopy are amongst the most specific optical technologies to identify the chemical compounds of unknown samples, and to enable label-free biomedical imaging with molecular contrast. However, the high cost and complexity, low speed, and incomplete spectral information provided by current technology are major challenges preventing more widespread application of Raman systems. To overcome these limitations, we developed a new method for stimulated Raman spectroscopy and Raman imaging using continuous wave (CW), rapidly wavelength swept lasers. Our all-fiber, time-encoded Raman (TICO-Raman) setup uses a Fourier Domain Mode Locked (FDML) laser source to achieve a unique combination of high speed, broad spectral coverage (750 cm-1 - 3150 cm-1) and high resolution (0.5 cm-1). The Raman information is directly encoded and acquired in time. We demonstrate quantitative chemical analysis of a solvent mixture and hyperspectral Raman microscopy with molecular contrast of plant cells.Comment: 9 pages, 4 figure

    Improving spatial resolution of confocal Raman microscopy by super-resolution image restoration

    Get PDF
    A new super-resolution image restoration confocal Raman microscopy method (SRIR-RAMAN) is proposed for improving the spatial resolution of confocal Raman microscopy. This method can recover the lost high spatial frequency of the confocal Raman microscopy by using Poisson-MAP super-resolution imaging restoration, thereby improving the spatial resolution of confocal Raman microscopy and realizing its super-resolution imaging. Simulation analyses and experimental results indicate that the spatial resolution of SRIR-RAMAN can be improved by 65% to achieve 200 nm with the same confocal Raman microscopy system. This method can provide a new tool for high spatial resolution micro-probe structure detection in physical chemistry, materials science, biomedical science and other areas

    High index contrast photonic platforms for on-chip Raman spectroscopy

    Get PDF
    Nanophotonic waveguide enhanced Raman spectroscopy (NWERS) is a sensing technique that uses a highly confined waveguide mode to excite and collect the Raman scattered signal from molecules in close vicinity of the waveguide. The most important parameters defining the figure of merit of an NWERS sensor include its ability to collect the Raman signal from an analyte, i.e. "the Raman conversion efficiency" and the amount of "Raman background" generated from the guiding material. Here, we compare different photonic integrated circuit (PIC) platforms capable of on-chip Raman sensing in terms of the aforementioned parameters. Among the four photonic platforms under study, tantalum oxide and silicon nitride waveguides exhibit high signal collection efficiency and low Raman background. In contrast, the performance of titania and alumina waveguides suffers from a strong Raman background and a weak signal collection efficiency, respectively
    • …
    corecore