This paper deals with the composition and chemical processes occurring in the neutral atmosphere of Venus. Since the last synthesis, observers as well as modellers have emphasised the spatial and ...temporal variability of minor species, going beyond a static and uniform picture that may have prevailed in the past. The outline of this paper acknowledges this situation and follows closely the different dimensions along which variability in composition can be observed: vertical, latitudinal, longitudinal, temporal. The strong differences between the atmosphere below and above the cloud layers also dictate the structure of this paper. Observational constraints, obtained from both Earth and
Venus Express
, as well as 1D, 2D and 3D models results obtained since 1997 are also extensively referred and commented by the authors. An non-exhaustive list of topics included follows: modelled and observed latitudinal and vertical profiles of CO and OCS below the clouds of Venus; vertical profiles of CO and SO
2
above the clouds as observed by solar occultation and modelled; temporal and spatial variability of sulphur oxides above the clouds. As a conclusion, open questions and topics of interest for further studies are discussed.
The habitability of the surface of any planet is determined by a complex evolution of its interior, surface, and atmosphere. The electromagnetic and particle radiation of stars drive thermal, ...chemical, and physical alteration of planetary atmospheres, including escape. Many known extrasolar planets experience vastly different stellar environments than those in our solar system: It is crucial to understand the broad range of processes that lead to atmospheric escape and evolution under a wide range of conditions if we are to assess the habitability of worlds around other stars. One problem encountered between the planetary and the astrophysics communities is a lack of common language for describing escape processes. Each community has customary approximations that may be questioned by the other, such as the hypothesis of H‐dominated thermosphere for astrophysicists or the Sun‐like nature of the stars for planetary scientists. Since exoplanets are becoming one of the main targets for the detection of life, a common set of definitions and hypotheses are required. We review the different escape mechanisms proposed for the evolution of planetary and exoplanetary atmospheres. We propose a common definition for the different escape mechanisms, and we show the important parameters to take into account when evaluating the escape at a planet in time. We show that the paradigm of the magnetic field as an atmospheric shield should be changed and that recent work on the history of Xenon in Earth's atmosphere gives an elegant explanation to its enrichment in heavier isotopes: the so‐called Xenon paradox.
Plain Language Summary
In addition to having the right surface temperature, a planet needs an atmosphere to keep surface liquid water stable. Although many planets have been found that may lie in the right temperature range, the existence of an atmosphere is not guaranteed. In particular, for planets that are kept warm by being close to dim stars, there are a number of ways that the star may remove a planetary atmosphere. These atmospheric escape processes depend on the behavior of the star as well as the nature of the planet, including the presence of a planetary magnetic field. Under certain conditions, a magnetic field can protect a planet's atmosphere from the loss due to the direct impact of the stellar wind, but it may actually enhance total atmospheric loss by connecting to the highly variable magnetic field of the stellar wind. These enhancements happen especially for planets close to dim stars. We review the complete range of atmospheric loss processes driven by interaction between a planet and a star to aid in the identification of planets that are both the correct temperature for liquid water and that have a chance of maintaining an atmosphere over long periods of time.
Key Points
The different escape processes at planets and exoplanets are reviewed along with their mathematical formulation
The major parameters for each escape processes are described; some escape processes negligible in the solar system may be major source at exoplanets, or for the early solar system
A magnetic field should not be a priori considered as a protection for the atmosphere
X-ray tomography is widely used for three-dimensional structure determination in many areas of science, from the millimeter to the nanometer scale. The resolution and quality of the 3D reconstruction ...is limited by the availability of alignment parameters that correct for the mechanical shifts of the sample or sample stage for the images that constitute a scan. In this paper we describe an algorithm for marker-free, fully automated and accurately aligned and reconstructed X-ray tomography data. Our approach solves the tomographic reconstruction jointly with projection data alignment based on a rigid-body deformation model. We demonstrate the robustness of our method on both synthetic phantom and experimental data and show that our method is highly efficient in recovering relatively large alignment errors without prior knowledge of a low resolution approximation of the 3D structure or a reasonable estimate of alignment parameters.
Previous research has identified numerous physical, psychological, and spiritual benefits associated with the practice of yoga. Indeed, yoga has been linked with improved quality of life, reduced ...stress, and numerous markers of psychological well-being. In the current research, a cross-sectional design was used to examine whether the psychological benefits associated with yoga only apply to long-term practitioners or whether more "casual," intermittent yoga experience could produce positive outcomes.
An American population of long-term practitioners (
= 129), intermittent practitioners (
= 161), and non-practitioners (
= 164) completed online self-report measures of emotional regulation, trait mindfulness, self-compassion, interoceptive awareness, and spiritual intelligence variables.
The results indicated that long-term (LT) practitioners scored higher than intermittent experience (IE) practitioners on measures of mindfulness (
= 137.3;
= 127.6), interoceptive awareness (
= 3.4;
= 3.1), self-compassion (
= 3.4;
= 3.1), and spiritual intelligence (
= 63.5;
= 55.5; all
-value < 0.05). Intermittent practitioners scored higher than no-experience (NE) group on interoceptive awareness (
= 3.1;
= 2.7) and spiritual intelligence (
= 55.5;
= 46.6; both
-value < 0.05). Contrary to our hypotheses, yoga experience had no effect on depression, anxiety, or stress levels. Separate mediation analyses demonstrated that interoceptive awareness, spiritual intelligence, mindfulness, and self-compassion each mediated the relationship between yoga experience and emotion dysregulation. Furthermore, emotion dysregulation mediated the relationship between yoga experience and depression, anxiety, and stress.
Taken together, the results of this study suggest that long-term practitioners experience more benefits compared to intermittent and non-practitioners, and that the mechanisms underlying these benefits are multi-faceted.
Purpose of Review
This review provides an evidence-based approach to improve health, reduce excessive medical costs, and optimize productivity for health care employees and their families. What ...opportunities and challenges are unique or specific to health care organizations particularly as aligned with value and competitive advantage in achieving the Quadruple Aim?
Recent Findings
An integrated approach to improving health and performance is essential. The strategy includes the employer “environment” (broadly defined), health and medical care behaviors, care delivery modalities, benefits alignment, and a supportive, total health and productivity integrated data analytic capability. Epigenetics and lifestyle medicine represent a promising direction in accelerating the prevention, treatment, and reversal of common chronic disease.
Summary
An integrated health and productivity approach, emerging science, and practices can accelerate health care systems’ goal to improve employee health and organizational competitiveness. Additional published examples of health care specific employer experience will further advance refinement of existing models and tailoring to the medical care setting.
Mindfulness has been described as an orienting of attention to the present moment, with openness and compassion. Individuals displaying high
mindfulness exhibit this tendency as a more permanent ...personality attribute. Given the numerous physical and mental health benefits associated with mindfulness, there is a great interest in understanding the neural substrates of this trait. The purpose of the current research was to examine how individual differences in trait mindfulness associated with functional connectivity in five resting-state networks related to cognition and attention: the default mode network (DMN), the salience network (SN), the central executive network (CEN), and the dorsal and ventral attention networks (DAN and VAN). Twenty-eight undergraduate participants completed the Five-Facet Mindfulness Questionnaire (FFMQ), a self-report measure of trait mindfulness which also provides scores on five of its sub-categories (
,
,
,
, and
). Participants then underwent a structural MRI scan and a 7-min resting state functional MRI scan. Resting-state data were analyzed using independent-component analyses. An analysis of covariance (ANCOVA) was performed to determine the relationship between each resting state network and each FFMQ score. These analyses indicated that: (1) trait mindfulness and its facets showed increased functional connectivity with neural regions related to attentional control, interoception, and executive function; and (2) trait mindfulness and its facets showed decreased functional connectivity with neural regions related to self-referential processing and mind wandering. These patterns of functional connectivity are consistent with some of the benefits of mindfulness-enhanced attention, self-regulation, and focus on present experience. This study provides support for the notion that non-judgmental attention to the present moment facilitates the integration of regions in neural networks that are related to cognition, attention, and sensation.
As climate change exacerbates exposure to disasters, a growing body of scholarship provides evidence that some groups experience significant barriers in accessing and participating in emergency ...services. This article reports on the findings of an exploratory, qualitative study involving in-depth interviews with four lesbian or bisexual women in Australia. The aim of the study is to better understand the degree to which emergency services’ policies, programs and procedures accommodate diversity and the needs of lesbian and bisexual women as ‘clients’ and paid staff or volunteers. Results are organised under five key categories: language; discrimination; sector acknowledgment; the role of faith-based organisations; and ways forward. The data is presented through the women’s voices and documents their lived experiences of discrimination. The study provides an opportunity to consider how discrimination against sexual and gender identity diverse minorities (LGBT people) intersects with, as it draws on, discrimination against women, increasing lesbian and bisexual women’s experiences of marginalisation as emergency sector clients, employees and volunteers. It also provides an opportunity to address the effects of systemic discrimination in the organisation and delivery of emergency services, promoting a more diverse and inclusive emergency sector.
Abstract
We present results for the first three years of OzDES, a six year programme to obtain redshifts for objects in the Dark Energy Survey (DES) supernova fields using the 2dF fibre positioner ...and AAOmega spectrograph on the Anglo-Australian Telescope. OzDES is a multi-object spectroscopic survey targeting multiple types of targets at multiple epochs over a multiyear baseline and is one of the first multi-object spectroscopic surveys to dynamically include transients into the target list soon after their discovery. At the end of three years, OzDES has spectroscopically confirmed almost 100 supernovae, and has measured redshifts for 17 000 objects, including the redshifts of 2566 supernova hosts. We examine how our ability to measure redshifts for targets of various types depends on signal-to-noise ratio (S/N), magnitude and exposure time, finding that our redshift success rate increases significantly at a S/N of 2–3 per 1-Å bin. We also find that the change in S/N with exposure time closely matches the Poisson limit for stacked exposures as long as 10 h. We use these results to predict the redshift yield of the full OzDES survey, as well as the potential yields of future surveys on other facilities such as (i.e. the 4-m Multi-Object Spectroscopic Telescope, the Subaru Prime Focus Spectrograph and the Maunakea Spectroscopic Explorer). This work marks the first OzDES data release, comprising 14 693 redshifts. OzDES is on target to obtain over 30 000 redshifts over the 6-yr duration of the survey, including a yield of approximately 5700 supernova host-galaxy redshifts.
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