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A standardless method of energy dispersive X-ray fluorescence in conjunction with scanning electron microscopy was used to analyze selected areas of clay-size particles of talc, pyrophyllite, and kaolinite supported by a carbon planchet. Peak intensity ratios of fluorescing elements relative to silicon were converted directly to weight or mole ratios using conversion factors determined theoretically. The conversion factors depend upon particle thickness and mass adsorption coefficients of the sample for the elements analyzed. The effects of particle thickness become significant above ~0.1 μm. Without using particle thickness corrections, the mean molar ratios of metal to Si agreed to within 6.1,0.5, and 9.7% of the theoretical ratios for kaolinite, pyrophyllite, and talc, respectively.
An ageing population and increased life expectancy are a characteristic of the Western world. Nevertheless, as Roger Fontaine writes, “although we should be glad about this fact, it should also be stressed that old age reveals profound discrepancies between individuals. In fact, we should not speak of ‘old age’ but ‘old ages’. Specialists make a distinction between normal old age, successful old age, and pathological old age.”
Catherine Guchet points out that, at the end of the twentieth century, two images of old age coexist, utilitarian in conception: that of ‘flamboyant’ old age and that of ‘dependent’ old age. The latter is associated with a loss of autonomy and dignity, especially for subjects affected by senile dementia, described as ‘unconscious’. We shall focus on these more problematic forms of old age.
Ultraviolet disinfection (UV-C), though effective, has not been thoroughly evaluated at the level of the clinical end user. We assessed behavioral outcomes related to environmental hygiene among 60 nursing staff in a medical-surgical section after introduction of a UV-C tool aimed at disinfecting 4 high-touch surfaces, and we noted limited changes.
Introduction: The incidence of out-of-hospital cardiac arrest (OHCA) in school is approximately 2.1 for 100,000 per year. Although rare, it is a devastating event for the local community. Schools with public access to automated external defibrillators (AED) and an emergency response plan have demonstrated increased survival rates of up to 70% for students who suffer cardiac arrest. Previous studies identified numerous barriers to successful cardiac resuscitation in public school systems. The main objectives of this study were to identify those barriers in the Quebec region elementary school system and to assess the impacts of an AED focused training session. Methods: A previously validated survey focused on the potential barriers to successful defibrillation in OHCA and on demographic variables was sent to 139 elementary schools. Later, 92 employees within three elementary schools who responded to the survey were evaluated before and after receiving training on the use of AED in a mock cardiac arrest scenario. The primary outcome was the time to first shock and the secondary outcomes included correct AED pad placement and safety of the procedure. Results: Survey response rate was 53%, which is comparable to previous studies assaying barriers to cardiac resuscitation in public school systems. 95% of school respondents reported the presence of an AED on the school premises but 46% stated that no formal AED training course was provided to employees. Out of the four schools who reported a previous OHCA, only one had access to an AED at the time of the event. Following focused AED training, 92% of school workers successfully completed a defibrillation sequence in a mock scenario, from 53% before (p < 0.001, McNemar test). The time to first shock went from 66 seconds (95% CI 63-70) to 47 seconds (95% CI 45-49; -29%, p < 0.001). Proper pad placement was the most problematic step for participants and personnel who reported previous training had better performance (OR 3.15, 95% CI 1.33-7.42, p = 0.009). Conclusion: Most elementary schools in the Quebec region have access to AEDs. However, inadequate AED training represents a significant barrier to successful defibrillation in the event of an OHCA. Our results showed that a simple focused AED training could improve the performance of school workers and optimize the chain of survival.
Recent attention models view exogenous and endogenous attention as separate components of attention. Exogenous attention is defined as automatic, involuntary, directed by external stimulation and unaffected by memory load, while endogenous attention is defined as executive, voluntary, directed by voluntary acts and affected by memory load. Methods. Two studies were designed to examine if decline in these two components of attention is similar in normal aging and Huntington's disease (HD). Standardized tests derived from Posner's model of visuospatial attention were administered to normal elderly subjects (n=13), patients with HD (n = 17) and matched control subjects (n = 42).
Results:
In healthy elderly subjects, both exogenous and endogenous attention were found to decline within normal limits, and the decrease was greater for endogenous attention, particularly in situations of perceptual conflict. Patients with HD showed marked impairment of endogenous or voluntary attention components, while exogenous or automatic components were preserved.
Conclusions:
Our results suggest that anterior executive and posterior automatic neuronal networks for attention are differentially vulnerable to the effects of normal aging and neurodegenerative diseases, despite the fact that both normal aging and HD are characterized by decreased endogenous attention in situations of perceptual conflict.
We computationally investigate coupling of a nonlinear rotational dissipative element to a sprung circular cylinder allowed to undergo transverse vortex-induced vibration (VIV) in an incompressible flow. The dissipative element is a ‘nonlinear energy sink’ (NES), consisting of a mass rotating at fixed radius about the cylinder axis and a linear viscous damper that dissipates energy from the motion of the rotating mass. We consider the Reynolds number range $20\leqslant Re\leqslant 120$, with $Re$ based on cylinder diameter and free-stream velocity, and the cylinder restricted to rectilinear motion transverse to the mean flow. Interaction of this NES with the flow is mediated by the cylinder, whose rectilinear motion is mechanically linked to rotational motion of the NES mass through nonlinear inertial coupling. The rotational NES provides significant ‘passive’ suppression of VIV. Beyond suppression however, the rotational NES gives rise to a range of qualitatively new behaviours not found in transverse VIV of a sprung cylinder without an NES, or one with a ‘rectilinear NES’, considered previously. Specifically, the NES can either stabilize or destabilize the steady, symmetric, motionless-cylinder solution and can induce conditions under which suppression of VIV (and concomitant reduction in lift and drag) is accompanied by a greatly elongated region of attached vorticity in the wake, as well as conditions in which the cylinder motion and flow are temporally chaotic at relatively low $Re$.
This study aimed to assess the influence of supra- and subglottic extensions and vocal fold mobility on outcome in a large monocentric cohort of 148 patients treated for tumour–node–metastasis stage T2N0 glottic carcinomas.
Methods:
In all, 107 glottic carcinoma patients had normal vocal fold mobility (T2aN0), and 41 had impaired vocal fold mobility (T2bN0). Treatment decisions were made by a multidisciplinary team.
Results:
Vocal fold mobility was associated with overall survival, disease-free survival, local control, larynx preservation and laryngectomy-free survival. For patients with T2a lesions, local control, laryngectomy-free survival and disease-free survival improved after surgery but overall survival did not. For patients with T2b lesions, local control, laryngectomy-free survival, disease-free survival and overall survival were all higher after surgery than after radiotherapy.
Conclusion:
This study highlights for the first time the importance of vocal fold mobility in treatment outcomes and is the first to assess its influence on survival. Updated tumour–node–metastasis classifications should consider the distinction between T2a and T2b lesions.
This book, first published in 2000, is devoted to developments in symbolic dynamics and comprises eight chapters. The first two are concerned with the study of symbolic sequences of 'low complexity', the following two introduce 'high complexity' systems. Chapter five presents results on asymptotic laws for the random times of occurrence of rare events. Chapter six deals with diophantine problems and combinatorial Ramsey theory. Chapter seven looks at the dynamics of symbolic systems arising from numeration systems, and finally chapter eight gives a complete description of the symbolic dynamics of Lorenz maps.
This paper offers a theoretical and empirical model of ecosystem-based fishery management. A multi-species and multi-fleet model integrating Lotka–Volterra trophic dynamics as well as production and profit assessments is developed and applied to the coastal fishery of French Guiana. This small-scale fishery constitutes a challenging example with high fish biodiversity, several non-selective fleets and a potentially increasing local food demand due to demographic growth. The dynamic model is calibrated with 13 species and four fleets using monthly catch and effort data from 2006 to 2009. Several contrasted fishing scenarios including status quo, total closure, economic and viable strategies are then simulated. They are compared from the viewpoints of both biodiversity preservation and socioeconomic performance, assuming fixed landing prices and fixed costs. We show that fishing outputs, including food supply and fleet profitability, can be sustained on average but a loss of species cannot be avoided.
Background: Suicide rates are higher in the over 65s than in younger adults and there is a strong link between deliberate self harm (DSH) and suicide in older people. The association between personality disorder (PD) and DSH in older adults remains uncertain. Our objective was to describe this association.
Methods: A case control study was conducted in which participants were: (i) those who had undertaken an act of DSH and (ii) a hospital-based control group drawn from a geographical contiguous population. PD was assessed using the Standardised Assessment of Personality (SAP)
Results: Seventy-seven cases of DSH were identified; 61 (79.2%) of these participants were interviewed. There were 171 potential controls identified of whom 140 (81.9%) were included. An SAP was completed in 45/61 (73.8%) of cases and 100/140 (71.4%) of controls. The mean age was 79.8 years (SD = 9, range 65–103). The crude odds ratio for the association between PD and DSH was 5.91 [(95% CI 2.3, 14.9) p<0.0001]. There was a strong interaction with age stratified at 80 years. There was no association between PD and DSH after age 80. The adjusted odds ratio for PD in the group <80 years was 20.5 [(95% CI 3, 141) p = 0.002]. Borderline and impulsive PD traits tended to be associated with an episode of DSH more than other personality types.
Conclusions: PD appears to be a strong and independent risk for an act of DSH in people aged between 65 and 80 years and should be looked for as part of any risk assessment in this population. Access to specialist services may be required to optimally manage this problem and reduce the subsequent risk of suicide.
We had a good discussion of various issues relating to cosmology and there has been a clear division of perceptions of what is considered important evidence. On the one side, the conventional one, we have heard the very detailed evidence of CMBR and high redshift supernovae, evidence that is popularized in the phrase “concordance cosmology.” The Universe according to this view went through an inflationary phase, had an era of nucleosynthesis and then had the surface of last scattering when the radiation background became decoupled from matter. The package comes with a large part of the matter energy (around 75%) being dark and hitherto unknown, a substantial part of strange kind of matter (21%) and only around 4% of ordinary matter that we are familiar with. Once you believe all of these ideas, you feel convinced that the cosmological problem is all but solved.
On the other side, some of us have been increasingly worried at what appears to be anomalous evidence, evidence that does not fit into the standard picture just mentioned. Even the very basic Hubble law applied to QSO redshifts seems to be threatened if one takes the evidence on anomalous redshifts seriously. In the 1970s when Chip Arp first started finding such examples, he was told that these were exceptions and that he should find more. He has been doing just that and his cases now include not just optical sources but also radio and X-ray sources. Then there is the evidence of periodicities of redshifts that has not gone away with larger samples. As I discussed, even the gamma ray burst sources appear to show the effect.
Strained Silicon On Insulator wafers are today envisioned as a natural and powerfulenhancement to standard SOI and/or bulk-like strained Si layers. For MOSFETs applications, thisnew technology potentially combines enhanced devices scalability allowed by thin films andenhanced electron and hole mobility in strained silicon. This paper is intended to demonstrate byexperimental results how a layer transfer technique such as the Smart Cut™ technology can be usedto obtain good quality tensile Strained Silicon On insulator wafers. Detailed experiments andcharacterizations will be used to characterize these engineered substrates and show that they arecompatible with the applications.
First results on formation of thin film GeOI structures by the Smart Cut™ technology are presented in this paper. Thin single crystal layers of Ge have been successfully transferred, via oxide bonding layer, onto standard Si substrates with diameters ranging from 100 to 200 mm. Compared to SOI manufacturing, the development of GeOI requires adaptation to the available germanium material, since the starting material can be either bulk Ge or an epitaxial layer. Some results will be presented for GeOI formation according to the different technological options. Germanium splitting kinetics will be discussed and compared to already published results. To show good quality of the GeOI structures, detailed characterization has been done by TEM cross sections for defect densities, interfaces abruptness and layers homogeneities evaluation. AFM was used for surface roughness measurements. These results help define procedures that are required to achieve large diameter high quality GeOI structures.
The study of naturally-occurring radiation and its associated risk is one of the preoccupations of bodies responsible for radiation protection. Cosmic particle flux is significantly higher on board aircraft that at ground level. Furthermore, its intensity depends on solar activity and eruptions. Due to their professional activity, flight crews and frequent flyers may receive an annual dose of some millisieverts. This is why the European directive adopted in 1996 requires the aircraft operators to assess the dose and to inform their flight crews about the risk. The effective dose is to be estimated using various experimental and calculation means. In France, the computerized system for flight assessment of exposure to cosmic radiation in air transport (SIEVERT) is delivered to airlines for assisting them in the application of the European directive. This dose assessment tool was developed by the French General Directorate of Civil Aviation (DGAC) and partners: the Institute for Radiation Protection and Nuclear Safety (IRSN), the Paris Observatory and the French Institute for Polar Research - Paul-Emile Victor (IPEV). This professional service is available on an Internet server accessible to companies with a public section. The system provides doses that consider the routes flown by aircraft. Various results obtained are presented.
Background. The level of efficiency of implicit memory in Alzheimer's disease remains unclear as previous studies using stem completion tasks have led to contradictory results.
Method. The present study used target words embedded in significant short texts that subjects were required to read aloud (i.e. to enhance semantic processing). Texts were presented in two perceptual situations: ‘simple’ (blank spaces delimitating words) and ‘complex’ (spaces were filled by ‘8’s). In the completion phase, patients had to write the first word that came to mind in order to complete a three-letter stem. The recognition phase explored explicit memory performance. The performance of 24 Alzheimer patients was compared to a matched sample of healthy controls.
Results. Reading times differed between groups and were shorter for healthy controls. Recognition was dramatically lower in patients, thus confirming the alteration of explicit memory in this pathology. However, a significant priming effect (e.g. the tendency to complete the stem with the aid of a previously explored word) was present in both groups and did not differ between patients and healthy controls.
Conclusions. The absence of a correlation between priming and recognition scores suggests that this result cannot be explained by an explicit memory bias. Moreover, as the priming level was identical whatever the perceptual aspect of the text, we suggest that the priming effect is not only mediated by perceptual processes but also by lexical and conceptual processes, which to some extent are preserved during the light and moderate stages of this disease.