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This project employs a geoarchaeological approach to explore human occupation of the highland wetlands (bofedales) and salt flats of the Dry Puna of northern Chile (>2500m above sea level) during the Holocene. Differences in the archaeological record of each ecosystem are tentatively suggested to relate to settlement patterns and the history of the landscape.
Previous research has proposed that there may be potential synergies between psychedelic and meditation interventions, but there are still knowledge gaps that merit further investigation.
Methods
Using a longitudinal observational research design with samples representative of the US and UK adult population with regard to sex, age, and ethnicity (N = 9732), we investigated potential associations between self-reported psychedelic use and meditation practice.
Results
The follow-up survey was completed by 7667 respondents (79% retention rate), with 100 respondents reporting psychedelic use during the 2-month study period (1.3% of follow-up respondents). In covariate-adjusted regression models, psychedelic use during the study period was associated with greater increases in the number of days of mindfulness meditation practice in the past week (B = 0.40, p = 0.004). Among those who reported psychedelic use during the study period, covariate-adjusted regression models revealed that the subjective experience of insight during respondents' most intense psychedelic experience in that period was also associated with greater increases in the number of days of mindfulness and loving-kindness or compassion meditation practice in the past week (B = 0.42, p = 0.021; B = 0.38, p = 0.017). Notably, more days of loving-kindness or compassion meditation practice in the past week at baseline was associated with less severe subjective feelings of death or dying during respondents' most intense psychedelic experience in the study period (B = −0.29, p = 0.037).
Conclusions
Psychedelic use might lead to greater engagement with meditation practices such as mindfulness meditation, while meditation practices such as loving-kindness or compassion medication might buffer against certain challenging experiences associated with psychedelic use.
We summarize what we assess as the past year's most important findings within climate change research: limits to adaptation, vulnerability hotspots, new threats coming from the climate–health nexus, climate (im)mobility and security, sustainable practices for land use and finance, losses and damages, inclusive societal climate decisions and ways to overcome structural barriers to accelerate mitigation and limit global warming to below 2°C.
Technical summary
We synthesize 10 topics within climate research where there have been significant advances or emerging scientific consensus since January 2021. The selection of these insights was based on input from an international open call with broad disciplinary scope. Findings concern: (1) new aspects of soft and hard limits to adaptation; (2) the emergence of regional vulnerability hotspots from climate impacts and human vulnerability; (3) new threats on the climate–health horizon – some involving plants and animals; (4) climate (im)mobility and the need for anticipatory action; (5) security and climate; (6) sustainable land management as a prerequisite to land-based solutions; (7) sustainable finance practices in the private sector and the need for political guidance; (8) the urgent planetary imperative for addressing losses and damages; (9) inclusive societal choices for climate-resilient development and (10) how to overcome barriers to accelerate mitigation and limit global warming to below 2°C.
Social media summary
Science has evidence on barriers to mitigation and how to overcome them to avoid limits to adaptation across multiple fields.
Bloodstream infections (BSIs) are a frequent cause of morbidity in patients with acute myeloid leukemia (AML), due in part to the presence of central venous access devices (CVADs) required to deliver therapy.
Objective:
To determine the differential risk of bacterial BSI during neutropenia by CVAD type in pediatric patients with AML.
Methods:
We performed a secondary analysis in a cohort of 560 pediatric patients (1,828 chemotherapy courses) receiving frontline AML chemotherapy at 17 US centers. The exposure was CVAD type at course start: tunneled externalized catheter (TEC), peripherally inserted central catheter (PICC), or totally implanted catheter (TIC). The primary outcome was course-specific incident bacterial BSI; secondary outcomes included mucosal barrier injury (MBI)-BSI and non-MBI BSI. Poisson regression was used to compute adjusted rate ratios comparing BSI occurrence during neutropenia by line type, controlling for demographic, clinical, and hospital-level characteristics.
Results:
The rate of BSI did not differ by CVAD type: 11 BSIs per 1,000 neutropenic days for TECs, 13.7 for PICCs, and 10.7 for TICs. After adjustment, there was no statistically significant association between CVAD type and BSI: PICC incident rate ratio [IRR] = 1.00 (95% confidence interval [CI], 0.75–1.32) and TIC IRR = 0.83 (95% CI, 0.49–1.41) compared to TEC. When MBI and non-MBI were examined separately, results were similar.
Conclusions:
In this large, multicenter cohort of pediatric AML patients, we found no difference in the rate of BSI during neutropenia by CVAD type. This may be due to a risk-profile for BSI that is unique to AML patients.
We summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding of Earth's sensitivity to carbon dioxide, finds that permafrost thaw could release more carbon emissions than expected and that the uptake of carbon in tropical ecosystems is weakening. Adverse impacts on human society include increasing water shortages and impacts on mental health. Options for solutions emerge from rethinking economic models, rights-based litigation, strengthened governance systems and a new social contract. The disruption caused by COVID-19 could be seized as an opportunity for positive change, directing economic stimulus towards sustainable investments.
Technical summary
A synthesis is made of ten fields within climate science where there have been significant advances since mid-2019, through an expert elicitation process with broad disciplinary scope. Findings include: (1) a better understanding of equilibrium climate sensitivity; (2) abrupt thaw as an accelerator of carbon release from permafrost; (3) changes to global and regional land carbon sinks; (4) impacts of climate change on water crises, including equity perspectives; (5) adverse effects on mental health from climate change; (6) immediate effects on climate of the COVID-19 pandemic and requirements for recovery packages to deliver on the Paris Agreement; (7) suggested long-term changes to governance and a social contract to address climate change, learning from the current pandemic, (8) updated positive cost–benefit ratio and new perspectives on the potential for green growth in the short- and long-term perspective; (9) urban electrification as a strategy to move towards low-carbon energy systems and (10) rights-based litigation as an increasingly important method to address climate change, with recent clarifications on the legal standing and representation of future generations.
Social media summary
Stronger permafrost thaw, COVID-19 effects and growing mental health impacts among highlights of latest climate science.
Decreased levels of polyunsaturated membrane fatty acids (PUFA) and increased activity of cytosolic phospholipase A2 (PLA2) enzymes (key regulating enzymes of membrane remodelling and PUFA availability) are supporting pillars of the “membrane phospholipids concept of schizophrenia”. Assuming that membrane PUFA profile and PLA2 activity are altered during the at risk phase of disorder and influenced by fatty acid supplementation, we investigated PUFA profiles and PLA2 activity simultaneously in ultra high-risk (UHR) subjects before and after (n-3) fatty acids supplementation.
Method
In 81 UHR patients (aged between 13 and 25 years) PUFA levels were assessed in erythrocyte membranes using gas chromatography, and cytosolic PLA2 activity was measured in blood serum using a fluorometric HPTLC-based assay. Measurements were performed before and after a 6 month interval of placebo-controlled supplementation with n-3 fatty acids.
Results
At baseline significant associations were found between (n-9) and (n-6)-PUFA levels and psychopathology (especially in negative symptoms) assessed by the PANSS according to PACE criteria. (n-3)-PUFA supplementation caused significant changes in (n-3)- and (n-6)-PUFA levels and a significant decrease of PLA2 activity.
Conclusion
Our results support associations between membrane biochemistry and psychopathology (especially negative symptoms) in people at risk to develop psychosis. Supplementation of n-3 PUFA increases PUFA availability at membrane level and modulates membrane repair and remodelling processes. Assuming that PLA2 activity reflects neuronal damage, PUFA supplementation might unfold neuroprotective effects.
Permafrost occupies 20 million square kilometres of Earth’s high-latitude and high-altitude landscapes. These regions are sensitive to climate change and human activities; hence, permafrost research is of considerable scientific and societal importance. However, the results of this research are generally not known by the general public. Communicating scientific concepts is an increasingly important task in the research world. Different ways to engage learners and incorporate narratives in teaching materials exist, yet they are generally underused. Here we report on an international scientific outreach project called “Frozen-Ground Cartoons”, which aims at making permafrost science accessible and fun for students, teachers, and parents through the creation of comic strips. We present the context in which the project was initiated, as well as recent education and outreach activities. The future phases of the project primarily involve a series of augmented reality materials, such as maps, photos, videos, and 3D drawings. With this project we aim to foster understanding of permafrost research among broader audiences, inspire future permafrost researchers, and raise public and science community awareness of polar science, education, outreach, and engagement.
Political science takes pride in objective and methodologically rigorous research. This should be reflected in a clear and concise writing style that convinces readers by the content of the research, not by the language used to report about it. This article demonstrates that this is true but only to a limited extent. It shows that—similar to recent findings from natural-sciences research—the frequency of positive words that political scientists use to describe their research has increased markedly in recent decades. At the same time, however, the magnitude of this increase is much less pronounced. The article discusses and analyzes potential explanations for this trend. We suspect that it can be attributed at least partly to changing norms in the discipline, in which research framed in a positive way is more likely to be published.
Counter-propagating and suitably polarized light (laser) beams can provide conditions for pair production. Here, we consider in more detail the following two situations: (i) in the homogeneity regions of anti-nodes of linearly polarized ultra-high intensity laser beams, the Schwinger process is dynamically assisted by a second high-frequency field, e.g. by an XFEL beam; and (ii) a high-energy probe photon beam colliding with a superposition of co-propagating intense laser and XFEL beams gives rise to the laser-assisted Breit–Wheeler process. The prospects of such bi-frequent field constellations with respect to the feasibility of conversion of light into matter are discussed.
Reconstruction with a vascularised flap provides the most reliable outcome, with post-operative cerebrospinal fluid leak rates of less than 5 per cent. This article aims to review and summarise the critical technical aspects of the vascularised flaps most commonly used for skull base reconstruction.
Results:
Vascularised flaps are classified as intranasal or extranasal. The intranasal group includes the Hadad–Bassagaisteguy nasoseptal flap, the Caicedo reverse nasoseptal flap, the nasoseptal rescue flap, the posteriorly or anteriorly based lateral wall flaps, and the middle turbinate flap. Extranasal flaps include the transfrontal pericranial and transpterygoid temporoparietal flaps.
Conclusion:
The Hadad–Bassagaisteguy nasoseptal flap is overwhelmingly favoured for reconstructing extensive defects of anterior, middle and posterior cranial base. Its pertinent technical features are described. However, it is essential to master the skills required for the various extranasal or regional vascularised flaps because each can offer a reconstructive alternative for specific patients, especially when open approaches are needed and/or intranasal vascularised flaps are not feasible.
The effects on the house fly, Musca domestica (L.), of a series of cis-9 alkenes containing 19–25 carbon atoms were investigated. An unexpectedly wide spectrum of these homologous hydrocarbons showed biological activity. Synergism and interesting changes in behavioural responses (excitement, mating, and orientation) varying with structure and concentration were observed.
Cognitive models focus on information and the computational manipulation of information. Rational models optimize the function that relates the input of a process to the output. In contrast, efficient algorithms minimize the computational cost of processing in terms of time. Minimizing time is a better criterion for normative models, because it reflects the energy costs of a physical system.