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Background: Helicopter Emergency Medical Services (HEMS) are a limited and expensive resource, and should be intelligently tasked. HEMS dispatch was identified as a key research priority in 2011, with a call to identify a 'general set of criteria with the highest discriminating potential'. However, there have been no published data analyses in the past decade that specifically address this priority, and this priority has been reaffirmed in 2023. The objective of this study was to define the dispatch criteria available at the time of the initial emergency call with the greatest HEMS utility using a large, regional, multi-organizational dataset in the UK. Methods: This retrospective observational study utilized dispatch data from a regional emergency medical service (EMS) and three HEMS organisations in the East of England, 2016–2019. In a logistic regression model, Advanced Medical Priority Dispatch System (AMPDS) codes with ≥ 50 HEMS dispatches in the study period were compared with the remainder to identify codes with high-levels of HEMS patient contact and HEMS-level intervention/drug/diagnostic (HLIDD). The primary outcome was to identify AMPDS codes with a > 10% HEMS dispatch rate of all EMS taskings that would result in 10–20 high-utility HEMS dispatches per 24-h period in the East of England. Data were analysed in R, and are reported as number (percentage); significance was p < 0.05. Results: There were n = 25,491 HEMS dispatches (6400 per year), of which n = 23,030 (90.3%) had an associated AMPDS code. n = 13,778 (59.8%) of HEMS dispatches resulted in patient contact, and n = 8437 (36.6%) had an HLIDD. 43 AMPDS codes had significantly greater rates of patient contact and/or HLIDD compared to the reference group. In an exploratory analysis, a cut-off of ≥ 70% patient contact rate and/or ≥ 70% HLIDD (with a > 10% HEMS dispatch of all EMS taskings) resulted in 17 taskings per 24-h period. This definition derived nine AMPDS codes with high HEMS utility. Conclusion: We have identified nine 'golden' AMPDS codes, available at the time of initial emergency call, that are associated with high-levels of whole-system and HEMS utility in the East of England. We propose that UK EMS should consider immediate HEMS dispatch to these codes. [ABSTRACT FROM AUTHOR]

Radioresistance—a living cell's response to, and development of resistance to ionising radiation—can lead to radiotherapy failure and/or tumour recurrence. We used Raman spectroscopy and machine learning to characterise biochemical changes that occur in acquired radioresistance for breast cancer cells. We were able to distinguish between wild-type and acquired radioresistant cells by changes in chemical composition using Raman spectroscopy and machine learning with 100% accuracy. In studying both hormone receptor positive and negative cells, we found similar changes in chemical composition that occur with the development of acquired radioresistance; these radioresistant cells contained less lipids and proteins compared to their parental counterparts. As well as characterising acquired radioresistance in vitro, this approach has the potential to be translated into a clinical setting, to look for Raman signals of radioresistance in tumours or biopsies; that would lead to tailored clinical treatments. [ABSTRACT FROM AUTHOR]

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]

Four different label-free, minimally invasive, live single cell analysis techniques were applied in a quantitative comparison, to characterize embryonic stem cells and the hepatocytes into which they were differentiated. Atomic force microscopy measures the cell's mechanical properties, Raman spectroscopy measures its chemical properties, and dielectrophoresis measures the membrane's capacitance. They were able to assign cell type of individual cells with accuracies of 91% (atomic force microscopy), 95.5% (Raman spectroscopy), and 72% (dielectrophoresis). In addition, stimulated Raman scattering (SRS) microscopy was able to easily identify hepatocytes in images by the presence of lipid droplets. These techniques, used either independently or in combination, offer label-free methods to study individual living cells. Although these minimally invasive biomarkers can be applied to sense phenotypical or environmental changes to cells, these techniques have most potential in human stem cell therapies where the use of traditional biomarkers is best avoided. Destructive assays consume valuable stem cells and do not characterize the cells which go on to be used in therapies; whereas immunolabeling risks altering cell behavior. It was suggested how these four minimally invasive methods could be applied to cell culture, and how they could in future be combined into one microfluidic chip for cell sorting. © 2016 International Society for Advancement of Cytometry [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]

We used three label-free minimally invasive methods to characterize individual cells derived from primary and secondary tumours from the same patient, and of the same type – colorectal. Raman spectroscopy distinguished cells by their biochemical ‘fingerprint’ in a vibrational spectrum with 100% accuracy, and revealed that the primary cell line contains more lipids and alpha-helix proteins, whereas the secondary cell line contains more porphyrins and beta-sheet proteins. Stimulated Raman scattering (SRS) microscopy distinguished cells in chemically-specific images of CH2 bonds which revealed lipid droplets in secondary tumour cells. Atomic force microscopy (AFM) was used to distinguish cells with 80% accuracy by measuring their elasticity – secondary tumour cells (SW620) are around 3 times softer than primary ones (SW480). As well as characterizing the physical and biochemical differences between cell lines in vitro, these techniques offer three novel methods which could potentially be used for diagnosis – to assign a tumour as primary or secondary. [ABSTRACT FROM AUTHOR]

Background: Residency applicants have the right to see letters of recommendation written on their behalf. It is not knownwhether applicants are affected bywaiving this right. Objectives Our multicenter study assessed how frequently residency applicants waived their FERPA rights to view their letters of recommendation, and whether this affected the ratings they were given by faculty. Methods: We reviewed all ERAS-submitted letters of recommendation to 14 ACGME-accredited programs in 2006-2007.We collected ERAS ID, program name, FERPA declaration, standardized letter of recommendation (SLOR) use, and SLOR Global Assessment ranking. The percentage of applicants who waived their FERPA rights was determined. Chi-square tests of independence assessed whether applicants' decision to waive their FERPA rights was associated with their SLOR Global Assessment. Results: We examined 1776 applications containing 6424 letters of recommendations. Of 2736 letters that specified a Global Assessment, 2550 (93%) applicants waived their FERPA rights, while 186 did not. Of the applicants who chose not to waive their rights, 45.6% received a ranking of Outstanding, 35.5% Excellent, 18.3% Very Good, and 1.6% Good. Of applicants who waived their FERPA rights, 35.1% received a ranking of Outstanding, 49.6% Excellent, 13.7% Very Good, and 1.6% Good. Applicants who did not waive their FERPA rights were more likely to receive an Outstanding Assessment (P = .003). Conclusions: The majority (93%) of residency applicants waived their FERPA rights. Those who did not waive their rights had a statistically higher chance of receiving an Outstanding Assessment than those who did. [ABSTRACT FROM AUTHOR]

In this review we describe label-free optical spectroscopy techniques which are able to non-invasively measure the (bio)chemistry in biological systems. Raman spectroscopy uses visible or near-infrared light to measure a spectrum of vibrational bonds in seconds. Coherent anti-Stokes Raman (CARS) microscopy and stimulated Raman loss (SRL) microscopy are orders of magnitude more efficient than Raman spectroscopy, and are able to acquire high quality chemically-specific images in seconds. We discuss the benefits and limitations of all techniques, with particular emphasis on applications in biomedicine—both in vivo (using fiber endoscopes) and in vitro (in optical microscopes). [ABSTRACT FROM AUTHOR]

There is a requirement for a noninvasive technique to monitor stem cell differentiation. Several candidates based on optical spectroscopy are discussed in this review: Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and coherent anti-Stokes Raman scattering (CARS) microscopy. These techniques are briefly described, and the ability of each to distinguish undifferentiated from differentiated cells is discussed. FTIR spectroscopy has demonstrated its ability to distinguish between stem cells and their derivatives. Raman spectroscopy shows a clear reduction in DNA and RNA concentrations during embryonic stem cell differentiation (agreeing with the well-known reduction in the nucleus to cytoplasm ratio) and also shows clear increases in mineral content during differentiation of mesenchymal stem cells. CARS microscopy can map these DNA, RNA, and mineral concentrations at high speed, and Mutliplex CARS spectroscopy/microscopy is highlighted as the technique with most promise for future applications. [ABSTRACT FROM AUTHOR]

Tip-enhanced optical spectroscopy is an approach that holds a good deal of promise for the nanoscale characterisation of matter. Tip-enhanced Raman spectroscopy (TERS) has been demonstrated on a variety of samples: inorganic, organic and biological. Imaging using TERS has been shown for carbon nanotubes due to their high scattering efficiency. There are a number of compelling motivations to consider alternative approaches for biological samples; most importantly, the potential for heat damage of biomolecules and long acquisition times. These issues may be addressed through the development of tip-enhanced coherent anti-Stokes Raman scattering microscopy. [ABSTRACT FROM AUTHOR]

We consider the boundary crossing problem for time-homogeneous diffusions and general curvilinear boundaries. Bounds are derived for the approximation error of the one-sided (upper) boundary crossing probability when replacing the original boundary by a different one. In doing so we establish the existence of the first-passage time density and provide an upper bound for this function. In the case of processes with diffusion interval equal to ℝ this is extended to a lower bound, as well as bounds for the first crossing time of a lower boundary. An extension to some time-inhomogeneous diffusions is given. These results are illustrated by numerical examples. [ABSTRACT FROM AUTHOR]

We have performed finite element electromagnetic analysis of ‘apertureless’ scanning near-field optical microscope tips. A variety of radii was considered, from 40 nm down to 1 nm, and the enhancement of optical scattering from the region beneath the probe apex was modelled in air and water. We observed sizeable spectral shifts when the radius decreases, together with a surprising increase in the amount of scattering from small tips. The lateral resolution is considered, which is shown to be always smaller than the tip radius, and for 1-nm-radius tips can allow atomic resolution imaging with sufficient optical enhancement. Gold, silver, copper and aluminium were modelled as tip materials. [ABSTRACT FROM AUTHOR]

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]

In recent years, inflation has been one of the pressing economic problems facing Caribbean governments. Some research has been undertaken to examine the dynamics of the inflationary process in the region. These studies have shown that the main factor contributing to the increase in retail prices over time has been the continual rise in import prices. Other factors such as wage rate, interest rate, and tax rate increases have also contributed to the inflationary process. The effects of inflation on resource allocation and use, the standard of living, and income distribution necessitate a detailed examination of the causes of inflation so that measures can be implemented to arrest the process. This study is an econometric investigation of the causes of inflation in Barbados during the period 1960-77. Previous studies on inflation in Barbados did not employ econometric techniques, and hence the extent to which various factors affect the rate of inflation was not quantified. First, I outline the inflationary experience in Barbados over the study period. Second, I present a model of the inflationary process, test it, and assess its forecasting ability. I conclude with some policy implications of this research and provide suggestions for further work. [ABSTRACT FROM AUTHOR]

Nucleosomes with histone H3 replaced by CENP-A direct kinetochore assembly. CENP-A nucleosomes from human and Drosophila have been reported to have reduced heights as compared to canonical octameric H3 nucleosomes, thus suggesting a unique tetrameric hemisomal composition. We demonstrate that octameric CENP-A nucleosomes assembled in vitro exhibit reduced heights, indicating that they are physically distinct from H3 nucleosomes and negating the need to invoke the presence of hemisomes. [ABSTRACT FROM AUTHOR]

We present true color maps of a metal surface imaged by scanning tunneling microscopy (STM). Light emission spectra were acquired at each imaging pixel, and converted into a real color map. A rough gold film was shown to exhibit minimal color changes across the sample, so spectra are dependent on material and not sample geometry, due to a small radius tip. A larger tip was still able to distinguish between Ag and Cu clusters with ∼10 nm resolution, despite the onset of geometric effects. We conclude that color mapping represents an ideal way of identifying metals in STM on the nanometer scale. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Suicide Risk Among Active and Retired Canadian Soldiers: The Role of Posttraumatic Stress Disorder" by A. Brunet and E. Monson in the September 2014 issue.

Myoblasts are muscle derived mesenchymal stem cell progenitors that have great potential for use in regenerative medicine, especially for cardiomyogenesis grafts and intracardiac cell transplantation. To utilise such cells for pre-clinical and clinical applications, and especially for personalized medicine, it is essential to generate a synchronised, homogenous, population of cells that display phenotypic and genotypic homogeneity within a population of cells. We demonstrate that the biomarker-free technique of dielectrophoresis (DEP) can be used to discriminate cells between stages of differentiation in the C2C12 myoblast multipotent mouse model. Terminally differentiated myotubes were separated from C2C12 myoblasts to better than 96% purity, a result validated by flow cytometry and Western blotting. To determine the extent to which cell membrane capacitance, rather than cell size, determined the DEP response of a cell, C2C12 myoblasts were co-cultured with GFP-expressing MRC-5 fibroblasts of comparable size distributions (mean diameter ∼10 μm). A DEP sorting efficiency greater than 98% was achieved for these two cell types, a result concluded to arise from the fibroblasts possessing a larger membrane capacitance than the myoblasts. It is currently assumed that differences in membrane capacitance primarily reflect differences in the extent of folding or surface features of the membrane. However, our finding by Raman spectroscopy that the fibroblast membranes contained a smaller proportion of saturated lipids than those of the myoblasts suggests that the membrane chemistry should also be taken into account. [ABSTRACT FROM AUTHOR]