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White dwarfs, the extremely dense remnants left behind by most stars after their death, are characterized by a mass comparable to that of the Sun compressed into the size of an Earth-like planet. In the resulting strong gravity, heavy elements sink towards the centre and the upper layer of the atmosphere contains only the lightest element present, usually hydrogen or helium1,2. Several mechanisms compete with gravitational settling to change a white dwarf’s surface composition as it cools3, and the fraction of white dwarfs with helium atmospheres is known to increase by a factor of about 2.5 below a temperature of about 30,000 kelvin4–8; therefore, some white dwarfs that appear to have hydrogen-dominated atmospheres above 30,000 kelvin are bound to transition to be helium-dominated as they cool below it. Here we report observations of ZTF J203349.8+322901.1, a transitioning white dwarf with two faces: one side of its atmosphere is dominated by hydrogen and the other one by helium. This peculiar nature is probably caused by the presence of a small magnetic field, which creates an inhomogeneity in temperature, pressure or mixing strength over the surface9–11. ZTF J203349.8+322901.1 might be the most extreme member of a class of magnetic, transitioning white dwarfs—together with GD 323 (ref. 12), a white dwarf that shows similar but much more subtle variations. This class of white dwarfs could help shed light on the physical mechanisms behind the spectral evolution of white dwarfs.The Zwicky Transient Facility has observed a transitioning white dwarf with two faces, with one side of its atmosphere dominated by hydrogen and the other by helium. [ABSTRACT FROM AUTHOR]

The unique geography of the Mozambique Channel largely results from the mountainous island of Madagascar, the fourth largest island in the world by area, extending 13 degrees of latitude. Madagascar, which forms the eastern boundary of the Mozambique Channel, is the only example worldwide of a large tropical island situated just offshore from a tropical-subtropical continent. The Channel has important consequences for southeastern African climate, oceanic circulation and is also a region of high biodiversity. Here, the annual cycle of the regional ocean–atmosphere interactions and circulation are synthesized to help explain some of the distinctive features of southeastern African climate, including the Mozambique Channel Trough, tropical cyclone and mesoscale convective system activity, and rainfall distributions. Upper ocean heat transport from the north into the Channel is greater than that south out of the Channel throughout the year, but particularly in March–April, so this region acts as a warm pool helping to fuel convective activity. From November to April, both Madagascar and Mozambique experience substantial shifts in the areas of maximum contribution to average rainfall from tropical cyclones. Over Mozambique, this average is impacted by the impact of relatively few very intense systems either making landfall or tracking close by in the Channel. However, on average, large areas of Mozambique receive ~ 10–30% of their summer rainfall from these systems whereas for Madagascar, the contribution is much higher (~ 30–70%). The greater frequency of intense tropical cyclones in March–April relative to the mid-summer appears related to the tropical cyclone heat potential reaching its maximum during these months. [ABSTRACT FROM AUTHOR]

Introduction: Antihyperglycemic agents are significant contributors to adverse drug events, responsible for emergency department visits, hospitalizations, and death. Nationally, the rate of serious hypoglycemic events associated with these agents remains high despite widespread efforts to improve drug safety. Transitions of care between healthcare settings can lead to communication challenges between care professionals and increase the risk of adverse drug events. System-based improvements are needed to assure the safe transitions for patients with diabetes who are on antihyperglycemic agents. The objective of this study was to develop a consensus list of requisite elements that should be communicated between care settings during transitions of patients who are prescribed antihyperglycemic agents. Methods: The Island Peer Review Organization (IPRO) Hypoglycemia Coalition identified suboptimal transitions of care as a barrier to improving patient safety and quality of diabetes care. The Coalition formed a multidisciplinary Task Force with experts in the field of diabetes care. The Task Force created a draft list of requisite communication elements through literature review and deliberation on monthly conference calls. A blinded iterative Delphi process was subsequently performed to generate a consensus list of requisite communication elements that participating experts agreed were necessary to safely and effectively assume the management of patients with diabetes upon care transitions. Results: The Task Force completed a series of four iterative polls from September 2015 to August 2016, resulting in a final list of 22 requisite communication elements (the Diabetes Management Discharge Communication List), with the elements conceptually categorized into three domains: diagnosis and treatment, factors affecting glycemic control or patient risk, and patient self-management. Conclusions: The Diabetes Management Discharge Communication List provides an initial framework for the development of diabetes-specific resources to improve clinical communication between care settings. [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHWs) are becoming more frequent and intense around the world leading to long-term impacts on ecosystems and subsequent socioeconomic consequences. To date, MHWs have not been considered in the Mozambique Channel, a highly biodiverse region with sensitive coral reefs. An assessment of MHW metrics here shows that these events tend to be more intense and last longer in the southeastern part of the channel especially during austral summer. Focus is placed on a particularly sensitive region west of southern Madagascar which shows significant positive trends in MHW metrics over the period 1982–2019 (frequency, intensity and duration). In austral summer 2017, this region experienced the longest and most intense MHW recorded in the past 35 years. This event lasted for 48 days and reached a maximum intensity of 3.44 °C above climatology. The warming largely resulted from anomalous net surface heat fluxes driven by weaker winds and increased insolation but was modulated by horizontal advection and the presence of an anticyclonic eddy. The wind and insolation anomalies were associated with a strong positive Subtropical Indian Ocean Dipole (SIOD), an anomalously weak Mozambique Channel Trough and westward extending Mascarene High. Correlation analysis suggests that long-lasting and intense MHW events occurring between January and March in this region may be associated with positive SIOD events. Changes in winds and surface heat fluxes associated with tropical cyclone Dineo appear to have briefly weakened the event in mid-February whereas those associated with ex-tropical cyclone Enawo appear to have contributed to its end in mid-March 2017. [ABSTRACT FROM AUTHOR]

Moisture sources and pathways over the Limpopo River Basin (LRB) in southern Africa were identified using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model applied to NCEP II (2.5° × 2.5°) reanalysis data for 1981–2016. The 10-day air parcel backward trajectories were produced for the extended wet season (October–April) as well as the early and late summer. Analysis of a 36-year climatology of air parcel trajectories indicated seven moisture source regions for the LRB; namely, local continental, tropical southeast Atlantic Ocean, midlatitude South Atlantic Ocean, tropical northwest Indian Ocean, tropical southwest Indian Ocean, subtropical southwest Indian Ocean, and the Agulhas Current. The results have shown that important differences in moisture source regions and pathways exist between early (October–December) and late (January–April) summers, with the tropical northwestern Indian Ocean and the northern Agulhas Current sources more prominent during JFMA than OND. On interannual time scales, there are notable differences in moisture source regions between anomalously wet and dry summers, with the South Indian Ocean moisture contribution and transport over the LRB smaller during dry summers than wet summers. Changes in specific humidity for trajectory linked to heavy daily rainfall events (defined from CHIRPS data) showed that subtropical South Indian Ocean source is more extensive for the heavy rainfall than for the moderate case. Generally, moisture source regions and transport pathways for LRB tend to be influenced by both the regional summer season circulation and the synoptic setting. [ABSTRACT FROM AUTHOR]

Asteroseismology probes the internal structures of stars by using their natural pulsation frequencies1. It relies on identifying sequences of pulsation modes that can be compared with theoretical models, which has been done successfully for many classes of pulsators, including low-mass solar-type stars2, red giants3, high-mass stars4 and white dwarfs5. However, a large group of pulsating stars of intermediate mass—the so-called δ Scuti stars—have rich pulsation spectra for which systematic mode identification has not hitherto been possible6,7. This arises because only a seemingly random subset of possible modes are excited and because rapid rotation tends to spoil regular patterns8–10. Here we report the detection of remarkably regular sequences of high-frequency pulsation modes in 60 intermediate-mass main-sequence stars, which enables definitive mode identification. The space motions of some of these stars indicate that they are members of known associations of young stars, as confirmed by modelling of their pulsation spectra. The pulsation spectra of intermediate-mass stars (so-called δ Scuti stars) have been challenging to analyse, but new observations of 60 such stars reveal remarkably regular sequences of high-frequency pulsation modes. [ABSTRACT FROM AUTHOR]

The management of type 2 diabetes mellitus in older adults requires a comprehensive understanding of the relationship between the disease (medical) and the functional, psychological/cognitive, and social geriatric domains, to individualize both glycemic targets and therapeutic approaches. Prevention of hypoglycemia is a major priority that should be addressed as soon as its presence or risk is detected, adjusting the target and therapeutics accordingly. Nonetheless, treatment intensification should not be neglected when applicable, consistent with recommendations from organizations such as the American Geriatrics Society and the American Diabetes Association, to reduce not only long-term macrovascular and microvascular complications (individualization), but also short-term complications from hyperglycemia (polyuria, volume depletion, urinary incontinence). Such complications can negatively impact the physical and cognitive function of older adults, worsen their quality of life, and additionally affect their families and society. We emphasize individualization, utilizing the multiple classes of antihyperglycemic agents available. Metformin remains as first-line therapy, and additional agents offer advantages and disadvantages that ought to be considered when developing a patient-centric plan of care. For selected cases, injectable therapies such as long-acting basal insulin analogs and glucagon-like peptide-1 receptor agonists can offer advantages to counter hypoglycemia risk, patient-related barriers, and clinical inertia. Furthermore, some injectable agents could potentially simplify regimens while providing safe and effective glycemic control. In this review, we discuss the use of injectable therapies for selected community-dwelling older adults, barriers to transition to injectable therapy, and measures aimed at removing these barriers and assisting physicians and their teams to transition older patients to injectable therapies when appropriate. [ABSTRACT FROM AUTHOR]

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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 107 grams 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. Photometry and parallax data from the Gaia satellite provide direct observational evidence of a theoretically predicted pile-up in the cooling sequence of white dwarfs, which is associated with core crystallization. [ABSTRACT FROM AUTHOR]

Investigating the variability of Agulhas leakage, the volume transport of water from the Indian Ocean to the South Atlantic Ocean, is highly relevant due to its potential contribution to the Atlantic Meridional Overturning Circulation as well as the global circulation of heat and salt and hence global climate. Quantifying Agulhas leakage is challenging due to the non-linear nature of this process; current observations are insufficient to estimate its variability and ocean models all have biases in this region, even at high resolution . An Eulerian threshold integration method is developed to examine the mechanisms of Agulhas leakage variability in six ocean model simulations of varying resolution. This intercomparison, based on the circulation and thermohaline structure at the Good Hope line, a transect to the south west of the southern tip of Africa , is used to identify features that are robust regardless of the model used and takes into account the thermohaline biases of each model. When determined by a passive tracer method, 60 % of the magnitude of Agulhas leakage is captured and more than 80 % of its temporal fluctuations, suggesting that the method is appropriate for investigating the variability of Agulhas leakage. In all simulations but one, the major driver of variability is associated with mesoscale features passing through the section. High resolution ( $${<} 1/10^{\circ }$$ ) hindcast models agree on the temporal (2-4 cycles per year) and spatial (300-500 km) scales of these features corresponding to observed Agulhas Rings. Coarser resolution models ( $${<} 1/4^{\circ }$$ ) reproduce similar time scale of variability of Agulhas leakage in spite of their difficulties in representing the Agulhas rings properties. A coarser resolution climate model ( $$2^{\circ }$$ ) does not resolve the spatio-temporal mechanism of variability of Agulhas leakage. Hence it is expected to underestimate the contribution of Agulhas Current System to climate variability. [ABSTRACT FROM AUTHOR]

Copyright of Forschung im Ingenieurwesen is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Several tumor immunotherapy approaches result in a low percentage of durable responses in selected cancers. We hypothesized that the insensitivity of cancer cells to immunotherapy may be related to an anti-apoptotic cancer cell milieu, which could be pharmacologically reverted through the inhibition of antiapoptotic Bcl-2 family proteins in cancer cells. ABT-737, a small molecule inhibitor of the antiapoptotic proteins Bcl-2, Bcl-w and Bcl-xL, was tested for the ability to increase antitumor immune responses in two tumor immunotherapy animal models. The addition of systemic therapy with ABT-737 to the immunization of BALB/c mice with tumor antigen peptide-pulsed dendritic cells (DC) resulted in a significant delay in CT26 murine colon carcinoma tumor growth and improvement in survival. However, the addition of ABT-737 to either a vaccine strategy involving priming with TRP-2 melanoma antigen peptide-pulsed DC and boosting with recombinant Listeria monocytogenes expressing the same melanoma antigen, or the adoptive transfer of TCR transgenic cells, did not result in superior antitumor activity against B16 murine melanoma. In vitro studies failed to demonstrate increased cytotoxic lytic activity when testing the combination of ABT-737 with lymphokine activated killer (LAK) cells, or the death receptor agonists Fas, TRAIL-ligand or TNF-alpha against the CT26 and B16 cell lines. In conclusion, the Bcl-2 inhibitor ABT-737 sensitized cancer cells to the antitumor effect of antigen-specific immunotherapy in a vaccine model for the CT26 colon carcinoma in vivo but not in two immunotherapy strategies against B16 melanoma. [ABSTRACT FROM AUTHOR]

The article Suitable Use of Injectable Agents to Overcome Hypoglycemia Risk, Barriers, and Clinical Inertia in Community-Dwelling Older Adults with Type 2 Diabetes Mellitus, written by Willy M. Valencia, Hermes J. Florez and Ana M. Palacio was originally published Online First without open access. [ABSTRACT FROM AUTHOR]