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Our understanding of climate dynamics during millennial-scale events is incomplete, partially due to the lack of their precise phase analyses under various boundary conditions. Here we present nine speleothem oxygen-isotope records from mid-to-low-latitude monsoon regimes with sub-centennial age precision and multi-annual resolution, spanning the Heinrich Stadial 2 (HS2) - a millennial-scale event that occurred at the Last Glacial Maximum. Our data suggests that the Greenland and Antarctic ice-core chronologies require +320- and +400-year adjustments, respectively, supported by extant volcanic evidence and radiocarbon ages. Our chronological framework shows a synchronous HS2 onset globally. Our records precisely characterize a centennial-scale abrupt "tropical atmospheric seesaw" superimposed on the conventional "bipolar seesaw" at the beginning of HS2, implying a unique response/feedback from low-latitude hydroclimate. Together with our observation of an early South American monsoon shift at the HS2 termination, we suggest a more active role of low-latitude hydroclimate dynamics underlying millennial events than previously thought.

Water-stable isotopes in polar ice cores are a widely used temperature proxy in paleoclimate reconstruction, yet calibration remains challenging in East Antarctica. Here, we reconstruct the magnitude and spatial pattern of Last Glacial Maximum surface cooling in Antarctica using borehole thermometry and firn properties in seven ice cores. West Antarctic sites cooled ~10°C relative to the preindustrial period. East Antarctic sites show a range from ~4° to ~7°C cooling, which is consistent with the results of global climate models when the effects of topographic changes indicated with ice core air-content data are included, but less than those indicated with the use of water-stable isotopes calibrated against modern spatial gradients. An altered Antarctic temperature inversion during the glacial reconciles our estimates with water-isotope observations.

A 45-year-old female dialysis patient with sudden onset of severe pain in the left shoulder and chest was referred for computed tomography of her left arm and thoracic veins. The computed tomography venography revealed 2 completely occluded venous grafts and 2 pronounced stenoses of the subclavian vein. By using a dual injection of diluted and undiluted contrast medium, artifact-free visualization of arteriovenous fistula, arm veins and adequate enhancement of thoracic veins were obtained. Keywords: Computed tomography, Arteriovenous fistula, Contrast agents-intravenous

We present a synchronization of the NGRIP, GRIP and GISP2 ice cores onto a master chronology extending back to 104ka before present, providing a consistent chronological framework for these three Greenland records. The synchronization aligns distinct peaks in volcanic proxy records and other impurity records (chemo-stratigraphic matching) and assumes that these layers of elevated impurity content represent the same, instantaneous event in the past at all three sites. More than 900 marker horizons between the three cores have been identified and our matching is independently confirmed by 24 new and previously identified volcanic ash (tephra) tie-points. Using the reference horizons, we transfer the widely used Greenland ice-core chronology, GICC05modelext, to the two Summit cores, GRIP and GISP2. Furthermore, we provide gas chronologies for the Summit cores that are consistent with the GICC05modelext timescale by utilizing both existing and new gas data (CH4 concentration and δ15N of N2). We infer that the accumulation contrast between the stadial and interstadial phases of the glacial period was ~10% greater at Summit compared to at NGRIP. The δ18O temperature-proxy records from NGRIP, GRIP, and GISP2 are generally very similar and display synchronous behaviour at climate transitions. The δ18O differences between Summit and NGRIP, however, changed slowly over the Last Glacial-Interglacial cycle and also underwent abrupt millennial-to-centennial-scale variations. We suggest that this observed latitudinal δ18O gradient in Greenland during the glacial period is the result of 1) relatively higher degree of precipitation with a Pacific signature at NGRIP, 2) increased summer bias in precipitation at Summit, and 3) enhanced Rayleigh distillation due to an increased source-to-site distance and a potentially larger source-to-site temperature gradient. We propose that these processes are governed by changes in the North American Ice Sheet (NAIS) volume and North Atlantic sea-ice extent and/or sea-surface temperatures (SST) on orbital timescales, and that changing sea-ice extent and SSTs are the driving mechanisms on shorter timescales. Finally, we observe that maxima in the Summit-NGRIP δ18O difference are roughly coincident with prominent Heinrich events. This suggests that the climatic reorganization that takes place during stadials with Heinrich events, possibly driven by a southward expansion of sea ice and low SSTs in the North Atlantic, are recorded in the ice-core records.

Background: Older patients are often vulnerable and highly dependent on healthcare professionals' assessment in the event of acute illness. In the context of ambulance services, this poses challenges as the assessment is normally conducted with a focus on identifying life-threatening conditions. Such assessment is not fully satisfactory in a patient relationship that also aims to promote and protect patient autonomy. Aim: To describe ambulance clinicians' understanding of older patients' self-determination when the patient's decision-making ability is impaired. Research design: A qualitative design with an inductive approach, guided by descriptive phenomenology. Participants: In total, 30 ambulance clinicians, comprised of 25 prehospital emergency nurses, 1 nurse and 4 emergency medical technicians participated in 15 dyadic interviews. Ethical considerations: The research was conducted in accordance with the Declaration of Helsinki, and permission was granted by the Swedish Ethical Review Authority. Findings: The findings are presented in two themes: (1) Movement between explicit and implicit will ; and (2) Contradictions about the patient's best interests. The clinicians' interpretations are based on an understanding of the patient's situation using substitute decision-making in emergency situations and conversations that reveal the patient's explicit wishes. Sometimes the clinicians collaborate to validate the patient's implicit will, while they at other times subordinate themselves to others' opinions. The clinicians find themselves in conflict between personal values and organisational values as they try to protect the patient's self-determination. Conclusion: The results indicate that older patients with an impaired decision-making ability risk losing the right to self-determination in the context of ambulance services. The clinicians face challenges that significantly affect their ability to handle the older patient's unique needs based on a holistic perspective and their ability to be autonomous. [ABSTRACT FROM AUTHOR]

Recently, a record of large, mostly unknown volcanic eruptions occurring during the younger half of the last glacial period (12–60 ka) has been compiled from ice-core records. In both Greenland and Antarctica these eruptions led to significant deposition of sulfate aerosols, which were likely transported in the stratosphere, thereby inducing a climate response. Here we report the first attempt to identify the climatic impact of volcanic eruptions in the last glacial period from ice cores. Average negative anomalies in high-resolution Greenland and Antarctic oxygen isotope records suggest a multi-annual volcanic cooling. Due to internal climate variability, glaciological noise, and uncertainties in the eruption age, the high-frequency noise level often exceeds the cooling induced by individual eruptions. Thus, cooling estimates for individual eruptions cannot be determined reliably. The average isotopic anomaly at the time of deposition also remains uncertain, since the signal degrades over time as a result of layer thinning and diffusion, which act to lower the resolution of both the oxygen isotope and sulfur records. Regardless of these quantitative uncertainties, there is a clear relationship of the magnitude of isotopic anomaly and sulfur deposition. Further, the isotopic signal during the cold stadial periods is larger in Greenland and smaller in Antarctica than during the milder interstadial periods for eruptions of equal sulfur deposition magnitude. In contrast, the largest reductions in snow accumulation associated with the eruptions occur during the interstadial periods. This may be the result of a state-dependent climate sensitivity, but we cannot rule out the possibility that changes in the sensitivity of the isotope thermometer or in the radiative forcing of eruptions of a given sulfur ejection may play a role as well. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to explore the tension between local, regional, and national authorities evoked by some rural municipalities' decisions to impose local infection-control measures during the first weeks of the COVID-19 pandemic in Norway. Methods: Eight municipal Chief Medical Officers of Health (CMOs) participated in semi-structured interviews, and six crisis management teams participated in focus-group interviews. Data were analysed with systematic text condensation. Boin and Bynander's interpretation of crisis management and coordination and Nesheim et al.'s framework for non-hierarchical coordination in the state sector inspired the analysis. Results: Uncertainty in the face of a pandemic with unknown damage potential, lack of infection-control equipment, patient transport challenges, vulnerable staff situation and planning of local COVID-19 beds were some of the reasons for rural municipalities imposing local infection-control measures the first weeks of the pandemic. Local CMOs' engagement, visibility and knowledge contributed to trust and safety. Differences in perspectives between local, regional and national actors created tension. Existing roles and structures were adjusted, and new informal networks arose. Conclusions: Strong municipal responsibility in Norway and the quite unique arrangement with local CMOs in every municipality with the legal right to decide temporary local infection-control measures seemed to facilitate a balance between top-down and bottom-up decision making. Tension between rural, regional and national actors that arose due to local infection-control measures, and the following dialogue and mutual adjustment of perspectives, led to a fruitful balance between national and local measures in Norway's handling of the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]