Effective mass and quantum lifetime in a Si/Si0.87Ge0.13/Si two-dimensional hole gas

Measurements of Shubnikov de Haas oscillations in the temperature range 0.3–2 K have been used to determine an effective mass of 0.23 m0 in a Si/Si0.87Ge0.13/Si two-dimensional hole gas. This value is in agreement with theoretical predictions and with that obtained from cyclotron resonance measurements. The ratio of the transport time to the quantum lifetime is found to be 0.8. It is concluded that the 4 K hole mobility of 11 000 cm2 V−1 s−1 at a carrier sheet density of 2.2×1011 cm−2 is limited by interface roughness and short-range interface charge scattering

Hole effective mass in remote doped Si/Si1−xGex quantum wells with 0.05x0.3

The effective masses in remote doped Si/Si1−xGex hole quantum wells with 0.05<=x<=0.3, have been determined from the temperature dependence of the Shubnikov–de Haas oscillations. The values are lower than previously observed by other workers, but still somewhat higher than the theoretical Gamma-point values for the ground-state heavy hole subband. The differences are attributed to finite carrier sheet densities and can be satisfactorily accounted for by nonparabolicity corrections

Hole effective mass in remote doped Si/Si1−xGex quantum wells with 0.05x0.3

The effective masses in remote doped Si/Si1−xGex hole quantum wells with 0.05<=x<=0.3, have been determined from the temperature dependence of the Shubnikov–de Haas oscillations. The values are lower than previously observed by other workers, but still somewhat higher than the theoretical Gamma-point values for the ground-state heavy hole subband. The differences are attributed to finite carrier sheet densities and can be satisfactorily accounted for by nonparabolicity corrections

Views of institutional leaders on maintaining humanism in today’s practice

Objective To explore leadership perspectives on how to maintain high quality efficient care that is also person-centered and humanistic. Methods The authors interviewed and collected narrative transcripts from a convenience sample of 32 institutional healthcare leaders at seven U.S. medical schools. The institutional leaders were asked to identify factors that either promoted or inhibited humanistic practice. A subset of authors used the constant comparative method to perform qualitative analysis of the interview transcripts. They reached thematic saturation by consensus on the major themes and illustrative examples after six conference calls. Results Institutional healthcare leaders supported vision statements, policies, organized educational and faculty development programs, role modeling including their own, and recognition of informal acts of kindness to promote and maintain humanistic patient-care. These measures were described individually rather than as components of a coordinated plan. Few healthcare leaders mentioned plans for organizational or systems changes to promote humanistic clinician-patient relationships. Conclusions Institutional leaders assisted clinicians in dealing with stressful practices in beneficial ways but fell short of envisaging systems approaches that improve practice organization to encourage humanistic care

Heart rate variability and soccer training: a case study

The aim of this study was to monitor changes in HRV indices of two players of the same soccer team during a training period. Training loads of each session of the 3-week period were monitored by means of the training impulses (TRIMP) method. Resting RR intervals at supine position were obtained at five moments over 3-week period. The HRV indices (SD1, SDNN, RMSSD and HF) followed similar inter-subject patterns. They had similar values at M1 and, from M2, these variables were greater in athlete 1 than in athlete 2. At M2 and M4, athlete 1 presented a parasympathetic rebound, especially in SD1, SDNN and RMSSD, whereas athlete 2 presented reduction of these indices. We can advance that indices of HRV can be useful to monitor the effects of soccer training/competitive loads on parasympathetic modulation, being sensitive to both individual characteristics and to periods of stress and recovery

How Physicians Draw Satisfaction and Overcome Barriers in their Practices: “It Sustains Me”

Objective Major reorganizations of medical practice today challenge physicians’ ability to deliver compassionate care. We sought to understand how physicians who completed an intensive faculty development program in medical humanism sustain their humanistic practices. Methods Program completers from 8 U.S. medical schools wrote reflections in answer to two open-ended questions addressing their personal motivations and the barriers that impeded their humanistic practice and teaching. Reflections were qualitatively analyzed using the constant comparative method. Results Sixty-eight physicians (74% response rate) submitted reflections. Motivating factors included: 1) identification with humanistic values; 2) providing care that they or their family would want; 3) connecting to patients; 4) passing on values through role modelling; 5) being in the moment. Inhibiting factors included: 1) time, 2) stress, 3) culture, and 4) episodic burnout. Conclusions Determination to live by one’s values, embedded within a strong professional identity, allowed study participants to alleviate, but not resolve, the barriers. Collaborative action to address organizational impediments was endorsed but found to be lacking. Practice implications Fostering fully mature professional development among physicians will require new skills and opportunities that reinforce time-honored values while simultaneously partnering with others to nurture, sustain and improve patient care by addressing system issues

Climate stories: enabling and sustaining arts interventions in climate science communication

This is the final version. Available from Copernicus Publications via the DOI in this record. Data availability. The research data used for this paper are not available in the public domain because of the ethical implications of making full transcripts available. The research was undertaken with a small sample of individuals from two institutions (University of Exeter and UK Met Office). The nature of the interview conversations held, which comprise the qualitative data in this paper, would enable individuals to be identified. Interviewees were specifically asked to discuss potentially sensitive issues related to their research training, experiences, emotions, feelings, and ethical positionality as part of the process of data collection. Because of this, publishing full interview transcripts would breach the ethical standard set for the research and approved by the Geography Ethics Committee at the University of Exeter, which stated that data would not be reported in a way that an individual could be identified. This was the basis for participants signing a consent form regarding how their data would be stored and used.The climate science community faces a major challenge with respect to communicating the risks associated with climate change within a heavily politicised landscape that is characterised by varying degrees of denial, scepticism, distrust in scientific enterprise, and an increased prevalence of misinformation (“fake news”). This issue is particularly significant given the reliance on conventional “deficit” communication approaches, which are based on the assumption that scientific information provision will necessarily lead to desired behavioural changes. Indeed, the constrained orthodoxy of scientific practices in seeking to maintain strict objectivity and political separation imposes very tangible limits on the potential effectiveness of climate scientists for communicating risk in many contemporary settings. To address these challenges, this paper uses insights from a collaboration between UK climate scientists and artist researchers to argue for a more creative and emotionally attentive approach to climate science engagement and advocacy. In so doing, the paper highlights innovative ways in which climate change communication can be reimagined through different art forms to enable complex concepts to become knowable. We suggest that in learning to express their work through forms of art, including print-making, theatre and performance, song-writing, and creative writing, researchers experienced not only a sense of liberation from the rigid communicative framework operating in their familiar scientific environment but also a growing self-confidence in their ability and willingness to engage in new ways of expressing their work. As such, we argue that scientific institutions and funding bodies should recognise the potential value of climate scientists engaging in advocacy through art–science collaborations and that these personal investments and contributions to science engagement by individuals should be rewarded and valued alongside conventional scientific outputs.Natural Environment Research Counci

Observation of an Excited Bc+ State

Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date