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Raman spectroscopy allows nondestructive analysis of materials using laser illumination. However, most Raman spectrometers can only provide good signal levels and sufficient spectral resolution, by focusing the laser to micrometer-sized spots. This equates to enormous laser intensities, which for samples with even very minor optical absorption either means destroying or damaging it by absorbing even a tiny fraction of the laser power, or it means reducing the laser intensity and hence the signal level. Furthermore, Raman signals generated above or below the focal plane are rejected in traditional Raman spectrometers. As signal levels are already extremely low in Raman spectroscopy, several schemes offer an alternative to focusing down to a diffraction-limited spot, to increase the area by up to 6 orders of magnitude, and increase the sampling depth. This review describes and compares these schemes, and estimates the typical illumination areas. [ABSTRACT FROM AUTHOR]

We present a Raman spectroscopy case study of living fibroblast (skin) cells from a patient who developed Huntington’s disease, with fibroblasts from a healthy volunteer as a control. Spectra were processed to remove cosmic rays, had a spectrum of the quartz substrate subtracted, and were flattened to remove cellular autofluorescence. We achieved an accuracy of 95% in discriminating individual cells, and assign spectral differences to (i) the reduction of cholesterol, (ii) the reduction of lipids, and (iii) an increase in beta-sheet proteins for fibroblasts with Huntington’s disease. All these biochemical changes have been previously measured by other methods. Averages over all the cells in this study yield a difference which is extremely statistically significant [p < 0.0001]. [ABSTRACT FROM AUTHOR]

Raman spectroscopy can identify cancerous from healthy tissue, with a chemical analysis from the measurement of vibrational bond frequencies. However, to detect small tumors a form of Raman imaging is required. Such imaging—by acquiring a Raman spectrum at each imaging pixel—can detect tumors but is rather slow. Multiphoton versions of Raman—anti-Stokes Raman scattering (CARS) microscopy and stimulated Raman scattering (SRS) microscopy—offer similar accuracies in identifying cancerous tissue and tumor margins but with a far higher speed, which is beneficial for diagnosis of small tumors in tissue. SRS microscopy can also be used to image extrinsic molecules in living cells, such as anti-cancer drugs at typical concentrations. [ABSTRACT FROM PUBLISHER]

Labour market and social policies both affect and are affected by the process of trade liberalization and globalization. This two-way interaction and the feedback effects are the focus of this paper. The analysis is mainly conceptual—but examples are illustrated throughout, based mainly in the context of labour markets in North America, Latin America and the Caribbean basin. Attention is paid to outlining the mechanisms whereby globalization and trade liberalization affect labour market and social policy initiatives, and the extent to which these pressures will lead to a harmonization of legislative and policy initiatives, and if that harmonization will necessarily be downward to the lowest common denominator. The paper concludes that: (1) the pressures will lead towards policy harmonization; (2) the harmonization generally will be downwards; (3) such harmonization is not always negative as generally perceived; (4) efficient regulatory and social policy initiatives will survive and indeed expand, with the ‘rent-protecting’ ones under most pressure to dissipate; and (5) pure distributional or equity-oriented initiatives that have no positive feedback effect on efficiency, unfortunately, will also be under jeopardy to dissipate, and this is a serious policy concern. Alternatives for addressing this concern are discussed, as are their associated problems. [ABSTRACT FROM AUTHOR]

Investigates what do theories of the functional deficits underlying amnesia have to explain. Features of organic amnesia; Hypotheses about the functional breakdown in amnesia; Objections to implicit memory hypothesis; Evidence relating to neuroanatomy.

In this final article in the special issue of Memory on Theories of Organic Amnesia, we select just three linked topics for further discussion: neuroanatomy, computational considerations, and tasks and procedures. Advances in each of these areas are reviewed and some recommendations for future directions are given. [ABSTRACT FROM AUTHOR]