Spectral absorption of biomass burning aerosol determined from retrieved single scattering albedo during ARCTAS

Actinic flux, as well as aerosol chemical and optical properties, were measured aboard the NASA DC-8 aircraft during the ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) mission in Spring and Summer 2008. These measurements were used in a radiative transfer code to retrieve spectral (350-550 nm) aerosol single scattering albedo (SSA) for biomass burning plumes encountered on 17 April and 29 June. Retrieved SSA values were subsequently used to calculate the absorption Angstrom exponent (AAE) over the 350-500 nm range. Both plumes exhibited enhanced spectral absorption with AAE values that exceeded 1 (6.78 ± 0.38 for 17 April and 3.34 ± 0.11 for 29 June). This enhanced absorption was primarily due to organic aerosol (OA) which contributed significantly to total absorption at all wavelengths for both 17 April (57.7%) and 29 June (56.2%). OA contributions to absorption were greater at UV wavelengths than at visible wavelengths for both cases. Differences in AAE values between the two cases were attributed to differences in plume age and thus to differences in the ratio of OA and black carbon (BC) concentrations. However, notable differences between AAE values calculated for the OA (AAEOA) for 17 April (11.15 ± 0.59) and 29 June (4.94 ± 0.19) suggested differences in the plume AAE values might also be due to differences in organic aerosol composition. The 17 April OA was much more oxidized than the 29 June OA as denoted by a higher oxidation state value for 17 April (+0.16 vs. -0.32). Differences in the AAEOA, as well as the overall AAE, were thus also possibly due to oxidation of biomass burning primary organic aerosol in the 17 April plume that resulted in the formation of OA with a greater spectral-dependence of absorption. © Author(s) 2012. CC Attribution 3.0 License

The impact of sound field systems on learning and attention in elementary school classrooms

Purpose: An evaluation of the installation and use of sound field systems (SFS) was carried out to investigate their impact on teaching and learning in elementary school classrooms. Methods: The evaluation included acoustic surveys of classrooms, questionnaire surveys of students and teachers and experimental testing of students with and without the use of SFS. Students ’ perceptions of classroom environments and objective data evaluating change in performance on cognitive and academic assessments with amplification over a six month period are reported. Results: Teachers were positive about the use of SFS in improving children’s listening and attention to verbal instructions. Over time students in amplified classrooms did not differ from those in nonamplified classrooms in their reports of listening conditions, nor did their performance differ in measures of numeracy, reading or spelling. Use of SFS in the classrooms resulted in significantly larger gains in performance in the number of correct items on the nonverbal measure of speed of processing and the measure of listening comprehension. Analysis controlling for classroom acoustics indicated that students ’ listening comprehension score

No Evidence for More Earth-sized Planets in the Habitable Zone of Kepler's M versus FGK Stars

Reliable detections of Earth-sized planets in the habitable zone remain elusive in the Kepler sample, even for M dwarfs. The Kepler sample was once thought to contain a considerable number of M dwarf stars ($T_\mathrm{eff} < 4000$ K), which hosted enough Earth-sized ($[0.5,1.5]$ R$_\oplus$) planets to estimate their occurrence rate ($\eta_\oplus$) in the habitable zone. However, updated stellar properties from Gaia have shifted many Kepler stars to earlier spectral type classifications, with most stars (and their planets) now measured to be larger and hotter than previously believed. Today, only one partially-reliable Earth-sized candidate remains in the optimistic habitable zone, and zero in the conservative zone. Here we performed a new investigation of Kepler's Earth-sized planets orbiting M dwarf stars, using occurrence rate models with considerations of updated parameters and candidate reliability. Extrapolating our models to low instellations, we found an occurrence rate of $\eta_\oplus={8.58}_{-8.22}^{+17.94}\%$ for the conservative habitable zone (and ${14.22}_{-12.71}^{+24.96}\%$ for the optimistic), consistent with previous works when considering the large uncertainties. Comparing these estimates to those from similarly comprehensive studies of Sun-like stars, we found that the current Kepler sample does not offer evidence to support an increase in $\eta_\oplus$ from FGK to M stars. While the Kepler sample is too sparse to resolve an occurrence trend between early and mid-to-late M dwarfs for Earth-sized planets, studies including larger planets and/or data from the K2 and TESS missions are well-suited to this task.Comment: 22 pages, 11 figures, 2 tables; Accepted for publication in A

Sleep assessment by patients and nurses in the intensive care: An exploratory descriptive study

© 2016. Background: Sleep disruption is common in intensive care unit (ICU) patients, with reports indicating reduced quality and quantity of sleep in many patients. There is growing evidence that sleep in this setting may be improved. Aim: To describe ICU patients' self-report assessment of sleep, examine the relationship between patients' self-reported sleep and their reported sleep by the bedside nurse, and describe the strategies suggested by patients to promote sleep. Methods: An exploratory descriptive study was undertaken with communicative adult patients consecutively recruited in 2014-2015. Patients reported sleep using the Richards-Campbell Sleep Questionnaire (score range 0-100. mm; higher score indicates better sleep quality), with nursing assessment of sleep documented across a five level ordinal variable. Patients were asked daily to describe strategies that helped or hindered their sleep. Ethical approval for the study was gained. Descriptive statistical analysis was performed [median (interquartile range)]; relationships were tested using Spearman's rank correlation and differences assessed using the Kruskal-Wallis test; . p . <. 0.05 was considered significant. Results: Participants (n = 151) were recruited [age: 60 (46-71) years; ICU length of stay 4 (2-9) days] with 356 self-reports of sleep. Median perceived sleep quality was 46 (26-65) mm. A moderate relationship existed between patients' self-assessment and nurses' assessment of sleep (Spearman's rank correlation coefficient 0.39-0.50; . p . <. 0.001). Strategies identified by patients to improve sleep included adequate pain relief and sedative medication, a peaceful and comfortable environment and physical interventions, e.g. clustering care, ear plugs. Conclusion: Patients reported on their sleep a median of 2 (1-3) days during their ICU stay, suggesting that routine use of self-report was feasible. These reports revealed low sleep quality. Patients reported multiple facilitators and barriers for sleep, with environmental and patient comfort factors being most common. Interventions that target these factors to improve patient sleep should be implemented

Exploring the meaning in meaningful coincidences: an interpretative phenomenological analysis of synchronicity in therapy

Synchronicity experiences (SEs) are defined as psychologically meaningful connections between inner events (e.g. thought, dream or vision) and one or more external events occurring simultaneously or at a future point in time. There has been limited systematic research that has investigated the phenomenology of SEs in therapy. This study aimed to redress this by exploring the process and nature of such experiences from the perspective of the practitioner. Semi-structured face-to-face interviews were conducted with a purposive sample of nine practitioners who reported SEs in their therapeutic sessions (three counsellors, three psychologists and three psychotherapists), and focused on how participants make sense of their experiences of synchronicity in therapy. Interpretative phenomenological analysis was used to identify three superordinate themes: sense of connectedness, therapeutic process, and professional issues. Findings suggest that SEs can serve to strengthen the therapeutic relationship and are perceived as useful harbingers of information about the therapeutic process, as well as being a means of overcoming communication difficulties, as they are seen to provide insights into the client’s experiencing of themselves and others, regardless of whether or not the SE is acknowledged by the client or disclosed by the therapist

Diaries For Intensive Care Unit Survivors (discuss): Perspectives Of Patients And Family Members Regarding Psychological Support

Rationale Diaries summarising care in the intensive care unit (ICU) have been incorporated into routine practice in some countries, although diary format, content, timing and method of delivery vary. The evidence and underpinning theory to support diary use is limited and uptake by patients and family members is infrequent raising questions of acceptance and generalisability. The purpose of this study was to elicit preferences of ICU survivors and their family members regarding diaries and other psychological support mechanisms, specifically if they wish to receive a diary or alternative psychological support material, what content they would like and preferred process and timing for receiving this information. Methods Patients in a general ICU for ≥3 days and their family members were invited to participate in this prospective exploratory study. Semi-structured interviews were conducted 3-5 months after ICU discharge via phone or in person. Interviews were transcribed verbatim and thematic analysis was conducted, with codes developed inductively using an iterative process and agreement on themes negotiated by team members. Results Forty-one survivors of critical illness and 26 family members consented to participation. Patients were usually male (63%), aged 50±18 years and stayed in ICU for median 8.5 (IQR 5.3-12.6) days. Patients and family members raised similar themes, although with a diverse range of opinion related to each aspect of ICU diary use. Considerations included: 1) memory and recall with some respondents wanting to know detail while others were either not curious or had no desire to be reminded of their ICU stay; 2) level of detail ranging from a comprehensive summary of clinical activities to a predominantly personal record of the experience; 3) the desire to develop shared memory of ICU and for the patient to understand what the family had been through; 4) timing of provision of diary from soon after the patient woke to months later; 5) concerns regarding the workload of staff to contribute to the diary; 6) potential to exacerbate or alternatively relieve stress; 7) uncertainty in regard to writing in diary as the patient may not survive; 8) ownership of the diary resting with the patient. Conclusions Common themes have been expressed by participants, although views regarding these themes were extremely diverse. Development of future interventions to aid psychological recovery must take into account these variable views to minimise the potential for causing distress to some survivors of critical illness and/or their family members whilst helping others

Order-Revealing Encryption and the Hardness of Private Learning

An order-revealing encryption scheme gives a public procedure by which two ciphertexts can be compared to reveal the ordering of their underlying plaintexts. We show how to use order-revealing encryption to separate computationally efficient PAC learning from efficient $(\epsilon, \delta)$-differentially private PAC learning. That is, we construct a concept class that is efficiently PAC learnable, but for which every efficient learner fails to be differentially private. This answers a question of Kasiviswanathan et al. (FOCS '08, SIAM J. Comput. '11). To prove our result, we give a generic transformation from an order-revealing encryption scheme into one with strongly correct comparison, which enables the consistent comparison of ciphertexts that are not obtained as the valid encryption of any message. We believe this construction may be of independent interest.Comment: 28 page