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The atmospheres of a large proportion of white dwarf stars are polluted by heavy elements1that are expected to sink out of visible layers on short timescales2,3. This has been interpreted as a signature of ongoing accretion of debris from asteroids4, comets5and giant planets6. This scenario is supported by the detection of debris discs7and transits of planetary fragments8around some white dwarfs. However, photospheric metals are only indirect evidence for ongoing accretion, and the inferred accretion rates and parent body compositions heavily depend on models of diffusion and mixing processes within the white dwarf atmosphere9–11. Here we report a 4.4σdetection of X-rays from a polluted white dwarf, G29–38. From the measured X-ray luminosity, we derive an instantaneous accretion rate of ṀX=1.63−0.40+1.29×109gs−1, which is independent of stellar atmosphere models. This rate is higher than estimates from past studies of the photospheric abundances of G29–38, suggesting that convective overshoot may be needed to model the spectra of debris-accreting white dwarfs. We measure a low plasma temperature of kBT= 0.5 ± 0.2 keV, corroborating the predicted bombardment solution for white dwarfs accreting at low accretion rates12,13.

The COVID-19 pandemic has forced leaders to reconsider the various factors that attribute to work-life balance, a healthy work environment, and resilience among nurses. Posttraumatic growth (PTG) provides a lens through which clinicians and leaders can measure, articulate, and espouse resilient recovery through unprecedented times. This article suggests the use of PTG as a framework, measured by the Posttraumatic Growth Inventory to guide leaders as they implement job-specific resiliency interventions for professional nurses. This article also suggests 3 science-based interventions intended to increase PTG. Published data support the efficacy of these interventions: resilience retreats, resilience rounds, and “The Pause,” while longitudinal impacts of PTG following these interventions remain currently unknown.

This article details a shared leadership structure and decision-making processes used to construct an innovative and evidence-based care delivery model for safety and optimal outcomes in the intensive care unit during the novel coronavirus (COVID-19) pandemic. Insights into ways professional development practitioners can facilitate changes in care delivery models, support nurses in their professional roles, and contribute to improved patient care outcomes during the COVID-19 pandemic are provided.

At big studios, an internal pipeline team and proprietary project management tools are usually a given. However, for smaller shops building everything from scratch isn't always realistic. When I joined [...]

OVERVIEW CMP processes are being used in an increasing number of applications in the wafer fab in response to shrinking device geometries with their increased need for planarity. There is […]

In the midst of the recent record-setting merger-and-acquisition activity among insurance agents and brokers, you may have pondered: Should we consider selling the firm, and if so, how can we [...]

White dwarfs are stellar embers depleted of nuclear energy sources that cool over billions of years1. These stars, which are supported by electron degeneracy pressure, reach densities of 107grams per cubic centimetre in their cores2. It has been predicted that a first-order phase transition occurs during white-dwarf cooling, leading to the crystallization of the non-degenerate carbon and oxygen ions in the core, which releases a considerable amount of latent heat and delays the cooling process by about one billion years3. However, no direct observational evidence of this effect has been reported so far. Here we report the presence of a pile-up in the cooling sequence of evolving white dwarfs within 100 parsecs of the Sun, determined using photometry and parallax data from the Gaia satellite4. Using modelling, we infer that this pile-up arises from the release of latent heat as the cores of the white dwarfs crystallize. In addition to the release of latent heat, we find strong evidence that cooling is further slowed by the liberation of gravitational energy from element sedimentation in the crystallizing cores5–7. Our results describe the energy released by crystallization in strongly coupled Coulomb plasmas8,9, and the measured cooling delays could help to improve the accuracy of methods used to determine the age of stellar populations from white dwarfs10.

In 2014, there were 357 announced agent-broker M&A transactions, an increase of more than 30% from the previous year and more than 10% higher than in 2012. Notwithstanding an extremely [...]

2012 was a record-breaking year for the number of announced insurance brokerage mergers and acquisitions, principally due to the higher capital gains tax that became effective in 2013. It was [...]

Ever increasing humanitarian crises involve prolonged population displacement, a known trigger for chronic stress, which in turn highlights the need for chronic stress to be addressed more explicitly within humanitarian aid work. This calls for better tools to both assess chronic stress in these situations of extended displacement, as well as methods to evaluate the impact of psychosocial interventions in such settings. Noting these challenges, this paper proposes the use of hair cortisol concentration sampling to measure long-term suffering and stress. By including cortisol hair testing as a quantitative measure to complement existing measures of psychosocial programme surveillance, researchers may better understand the nature of chronic stress. Sampling any sort of biomarker, such as cortisol concentration in hair, raises ethical and logistical concerns, therefore this paper address these issues as well, maintaining that a ‘do no harm’ position should take priority over the decision to measure hair cortisol concentration. Furthermore, as there is also a paucity of evidence regarding the validity of hair cortisol testing on humans, further research will be required.

Reports on the Morris Island, Charleston-based prisoner-of-war camp in South Carolina built by the union army forces so that the prisoners could be used as a human shield in front of Battery Wagner. Bombardment of Charleston region by Union troops; Transfer of federal prisoners to the besieged area by the confederate forces; Reprisal by union forces; Conditions for the confederate prisoners in the camp.

Surgical adjuvants are commonly employed to reduce the frequency of postoperative adhesion development after reproductive pelvic surgery. The ability of indomethacin, promethazine, dexamethasone, Intralipid, progesterone, and heparin to reduce adhesion formation in combination with INTERCEED(TC7) (Johnson and Johnson Medical, Inc., New Brunswick, NJ), an absorbable barrier that alone reduces adhesion formation, was examined in a rabbit uterine horn model. A significant reduction in adhesion formation was only observed with the combination of INTERCEED(TC7) plus heparin. In additional studies, heparin delivery by intraperitoneal (IP) lavage, intravenous injection, or intra-abdominal instillation failed to demonstrate efficacy. Similarly, heparin delivery with other barriers or IP instillates (carboxymethylcellulose or 32% Dextran 70) failed to reduce adhesion formation. We conclude that INTERCEED(TC7) can be efficaciously utilized as a carrier to deliver heparin to traumatized surfaces, thereby reducing adhesion formation.

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The poem "THE ANCESTRAL PILE REVISITED" by Tim Cunningham is presented. First Line: Six years young, hair combed, Last Line: Was pure imagination.

The poem "MWOAH!" by Tim Cunningham is presented. First Line: At a loss for words, Shakespeare; Last Line: Now, wouldn't that be a laugh.

The poem "Doing It for the Children" by Tim Cunningham is presented. First Line: It was the darkest night. Last Line: And fell into the most beautiful dream.

The poem "Raspberry Ripple," by Tim Cunningham is presented. First Line: Compelled by its Svengali call, Last Line: In raspberry, deliciously discreet.