3,533 research outputs found

    Gender and educational leadership in England: a comparison of secondary headteachers' views over time

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    In the context of gender being a barrier to accessing leadership, this paper presents a comparison of the views of men and women head teacher (principals) of secondary schools in England in the 1990s and in 2004. The same survey instrument was used on both occasions. The perceptions of the head teachers show change in some areas and no change in others. Overall, women are more likely to become head teachers and are now less likely to be categorised into pastoral roles, but in some cases women still meet prejudice from governors and others in the wider community. Women head teachers are more likely to have partners and children than in the 1990s, sharing equally or carrying most of the domestic responsibilities, whereas male colleagues are most likely to have partners who take the majority of responsibility in the home. Essentialist stereotypes about women and men as leaders still prevail, although both the women and men head teachers see themselves as adopting a traditionally ‘feminine’ style of leadership. Women head teachers are likely to see some benefits in being a woman in a role stereotypically associated with men. However, there has been an increase in the proportion of women who feel that they have to prove their worth as a leader, and this may be linked with increased levels of accountability in schools

    Measurements of Scintillation Efficiency and Pulse-Shape for Low Energy Recoils in Liquid Xenon

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    Results of observations of low energy nuclear and electron recoil events in liquid xenon scintillator detectors are given. The relative scintillation efficiency for nuclear recoils is 0.22 +/- 0.01 in the recoil energy range 40 keV - 70 keV. Under the assumption of a single dominant decay component to the scintillation pulse-shape the log-normal mean parameter T0 of the maximum likelihood estimator of the decay time constant for 6 keV < Eee < 30 keV nuclear recoil events is equal to 21.0 ns +/- 0.5 ns. It is observed that for electron recoils T0 rises slowly with energy, having a value ~ 30 ns at Eee ~ 15 keV. Electron and nuclear recoil pulse-shapes are found to be well fitted by single exponential functions although some evidence is found for a double exponential form for the nuclear recoil pulse-shape.Comment: 11 pages, including 5 encapsulated postscript figure

    Quantum measurements in continuous time, non Markovian evolutions and feedback

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    In this article we reconsider a version of quantum trajectory theory based on the stochastic Schr\"odinger equation with stochastic coefficients, which was mathematically introduced in the '90s, and we develop it in order to describe the non Markovian evolution of a quantum system continuously measured and controlled thanks to a measurement based feedback. Indeed, realistic descriptions of a feedback loop have to include delay and thus need a non Markovian theory. The theory allows to put together non Markovian evolutions and measurements in continuous time in agreement with the modern axiomatic formulation of quantum mechanics. To illustrate the possibilities of such a theory, we apply it to a two-level atom stimulated by a laser. We introduce closed loop control too, via the stimulating laser, with the aim to enhance the "squeezing" of the emitted light, or other typical quantum properties. Note that here we change the point of view with respect to the usual applications of control theory. In our model the "system" is the two-level atom, but we do not want to control its state, to bring the atom to a final target state. Our aim is to control the "Mandel QQ-parameter" and the spectrum of the emitted light; in particular the spectrum is not a property at a single time, but involves a long interval of times (a Fourier transform of the autocorrelation function of the observed output is needed).Comment: Latex, 19 pages, 3 figures; added references and "Conclusions"; expanded explanations. To appear in Phil. Trans. R. Soc.

    Systemic Therapy of Bronchioloalveolar Carcinoma: Results of the First IASLC/ASCO Consensus Conference on Bronchioloalveolar Carcinoma

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    Introduction:Bronchioloalveolar carcinoma (BAC) is a subtype of adenocarcinoma of the lung with unique pathological, clinical, and molecular characteristics.Methods:This consensus conference group reviewed studies performed specifically in BAC and data from patients with BAC who were included in clinical trials of all non–small-cell lung cancer (NSCLC) subtypes.Results:Although BAC as defined by the World Health Organization represents less than 5% of adenocarcinomas, as many as 20% of adenocarcinomas have BAC features. These latter tumors are more likely to have mutations in the epidermal growth factor receptor (EGFR) gene and to be sensitive to the EGFR tyrosine kinase inhibitors gefitinib and erlotinib. Although most patients are men and have a history of smoking cigarettes, proportionally more are women and never smokers. Patients with BAC are routinely treated with drugs and regimens appropriate for patients with all subtypes of adenocarcinoma of the lung; four studies have been performed specifically in this disease.Conclusions:There is insufficient evidence to confirm or refute the assertion that the sensitivity of BAC to chemotherapy is different from that of other lung cancer histologic types. The unique clinical and molecular characteristics associated with BAC led this panel to conclude that future clinical trials should be designed specifically for persons with BAC. Recommendations for trial design and research questions are proposed

    The impact of assistive technology on burden and psychological well-being in informal caregivers of people with dementia (ATTILA Study)

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    INTRODUCTION: Assistive technology and telecare (ATT) may alleviate psychological burden in informal caregivers of people with dementia. This study assessed the impact of ATT on informal caregivers’ burden and psychological well‐being. METHODS: Individuals with dementia and their informal caregivers were recruited to a randomized‐controlled trial assessing effectiveness of ATT. Caregivers were allocated to two groups according to their cared‐for person's randomization to a full or basic package of ATT and were assessed on caregiver burden, state anxiety, and depression. Caregivers’ data from three assessments over 6 months of the trial were analyzed. RESULTS: No significant between‐ or within‐group differences at any time point on caregivers’ burden, anxiety, and depression levels were found. DISCUSSION: Full ATT for people with dementia did not impact caregivers’ psychological outcomes compared to basic ATT. The length of follow up was restricted to 6 months

    The Distribution Of Heavy Elements In Spiral And Elliptical Galaxies

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    This review recaps significant results as they apply to non-dwarf galaxies, including the Milky Way, spiral disks and bulges, and elliptical and lenticular galaxies. Conclusions that span the galaxy types treated here are as follows. All galaxies, on average, have heavy element abundances (metallicities) that systematically decrease outward from their galactic centers while their global metallicities increase with galaxy mass. Abundance gradients are steepest in normal spirals and are seen to be progressively flatter going in order from barred spirals, lenticulars, and ellipticals. For spiral galaxies, local metallicity appears to be correlated with total (disk plus bulge) surface density. Observed abundance patterns indicate that N production is dominated by primary processes at low metallicity and secondary processes at high metallicity; C production increases with increasing metallicity; and O, Ne, S, and Ar are produced in lockstep independent of metallicity. In elliptical galaxies, nuclear abundances are in the range [Z/H] = 0.0 to 0.4, but the element mixture is not scaled-solar. In large elliptical galaxies [Mg/Fe] is in the range 0.3 to 0.5, decreasing to ~0 in smaller elliptical galaxies. Other light elements track the Mg enhancement, but the heavier Ca tracks Fe. Velocity dispersion appears to be a key parameter in the modulation of [Mg/Fe], but the cause of the connection is unclear.Comment: 55-page manuscript plus 16 figures. Invited review to appear in the Publications Of The Astronomical Society Of The Pacifi

    'To live and die [for] Dixie': Irish civilians and the Confederate States of America

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    Around 20,000 Irishmen served in the Confederate army in the Civil War. As a result, they left behind, in various Southern towns and cities, large numbers of friends, family, and community leaders. As with native-born Confederates, Irish civilian support was crucial to Irish participation in the Confederate military effort. Also, Irish civilians served in various supporting roles: in factories and hospitals, on railroads and diplomatic missions, and as boosters for the cause. They also, however, suffered in bombardments, sieges, and the blockade. Usually poorer than their native neighbours, they could not afford to become 'refugees' and move away from the centres of conflict. This essay, based on research from manuscript collections, contemporary newspapers, British Consular records, and Federal military records, will examine the role of Irish civilians in the Confederacy, and assess the role this activity had on their integration into Southern communities. It will also look at Irish civilians in the defeat of the Confederacy, particularly when they came under Union occupation. Initial research shows that Irish civilians were not as upset as other whites in the South about Union victory. They welcomed a return to normalcy, and often 'collaborated' with Union authorities. Also, Irish desertion rates in the Confederate army were particularly high, and I will attempt to gauge whether Irish civilians played a role in this. All of the research in this paper will thus be put in the context of the Drew Gilpin Faust/Gary Gallagher debate on the influence of the Confederate homefront on military performance. By studying the Irish civilian experience one can assess how strong the Confederate national experiment was. Was it a nation without a nationalism
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