Dynamic Jahn-Teller effect in electron transport through single C60 molecules

Scanning tunneling spectra on single C60 molecules that are sufficiently decoupled from the substrate exhibit a characteristic fine structure, which is explained as due to the dynamic Jahn-Teller effect. Using electron-phonon couplings extracted from density functional theory we calculate the tunneling spectrum through the C60- anionic state and find excellent agreement with measured data.Comment: 4 pages, 3 figures, 1 tabl

Lactate levels in severe malarial anaemia are associated with haemozoin-containing neutrophils and low levels of IL-12

BACKGROUND: Hyperlactataemia is often associated with a poor outcome in severe malaria in African children. To unravel the complex pathophysiology of this condition the relationship between plasma lactate levels, parasite density, pro- and anti-inflammatory cytokines, and haemozoin-containing leucocytes was studied in children with severe falciparum malarial anaemia. METHODS: Twenty-six children with a primary diagnosis of severe malarial anaemia with any asexual Plasmodium falciparum parasite density and Hb < 5 g/dL were studied and the association of plasma lactate levels and haemozoin-containing leucocytes, parasite density, pro- and anti-inflammatory cytokines was measured. The same associations were measured in non-severe malaria controls (N = 60). RESULTS: Parasite density was associated with lactate levels on admission (r = 0.56, P < 0.005). Moreover, haemozoin-containing neutrophils and IL-12 were strongly associated with plasma lactate levels, independently of parasite density (r = 0.60, P = 0.003 and r = -0.46, P = 0.02, respectively). These associations were not found in controls with uncomplicated malarial anaemia. CONCLUSION: These data suggest that blood stage parasites, haemozoin and low levels of IL-12 may be associated with the development of hyperlactataemia in severe malarial anaemia

ChatGPT versus human essayists: an exploration of the impact of artificial intelligence for authorship and academic integrity in the humanities

Generative AI has prompted educators to reevaluate traditional teaching and assessment methods. This study examines AI’s ability to write essays analysing Old English poetry; human markers assessed and attempted to distinguish them from authentic analyses of poetry by first-year undergraduate students in English at the University of Oxford. Using the standard UK University grading system, AI-written essays averaged a score of 60.46, whilst human essays achieved 63.57, a margin of difference not statistically significant (p = 0.10). Notably, student submissions applied a nuanced understanding of cultural context and secondary criticism to their close reading, while AI essays often described rather than analysed, lacking depth in the evaluation of poetic features, and sometimes failing to properly recognise key aspects of passages. Distinguishing features of human essays included detailed and sustained analysis of poetic style, as well as spelling errors and lack of structural cohesion. AI essays, on the other hand, exhibited a more formal structure and tone but sometimes fell short in incisive critique of poetic form and effect. Human markers correctly identified the origin of essays 79.41% of the time. Additionally, we compare three purported AI detectors, finding that the best, ‘Quillbot’, correctly identified the origin of essays 95.59% of the time. However, given the high threshold for academic misconduct, conclusively determining origin remains challenging. The research also highlights the potential benefits of generative AI’s ability to advise on structuring essays and suggesting avenues for research. We advocate for transparency regarding AI’s capabilities and limitations, and this study underscores the importance of human critical engagement in teaching and learning in Higher Education. As AI’s proficiency grows, educators must reevaluate what authentic assessment is, and consider implementing dynamic, holistic methods to ensure academic integrity

Current worldwide nuclear cardiology practices and radiation exposure: results from the 65 country IAEA Nuclear Cardiology Protocols Cross-Sectional Study (INCAPS)

AIMS To characterize patient radiation doses from nuclear myocardial perfusion imaging (MPI) and the use of radiation-optimizing 'best practices' worldwide, and to evaluate the relationship between laboratory use of best practices and patient radiation dose. METHODS AND RESULTS We conducted an observational cross-sectional study of protocols used for all 7911 MPI studies performed in 308 nuclear cardiology laboratories in 65 countries for a single week in March-April 2013. Eight 'best practices' relating to radiation exposure were identified a priori by an expert committee, and a radiation-related quality index (QI) devised indicating the number of best practices used by a laboratory. Patient radiation effective dose (ED) ranged between 0.8 and 35.6 mSv (median 10.0 mSv). Average laboratory ED ranged from 2.2 to 24.4 mSv (median 10.4 mSv); only 91 (30%) laboratories achieved the median ED ≤ 9 mSv recommended by guidelines. Laboratory QIs ranged from 2 to 8 (median 5). Both ED and QI differed significantly between laboratories, countries, and world regions. The lowest median ED (8.0 mSv), in Europe, coincided with high best-practice adherence (mean laboratory QI 6.2). The highest doses (median 12.1 mSv) and low QI (4.9) occurred in Latin America. In hierarchical regression modelling, patients undergoing MPI at laboratories following more 'best practices' had lower EDs. CONCLUSION Marked worldwide variation exists in radiation safety practices pertaining to MPI, with targeted EDs currently achieved in a minority of laboratories. The significant relationship between best-practice implementation and lower doses indicates numerous opportunities to reduce radiation exposure from MPI globally

Does "chaining" always really work towards compliance gaining? The case of the "but you are free" technique and social proof applied to charitable donation

The chaining procedure consists in linking together two or more compliance gaining strategies in order to obtain greater behavioral compliance. In two studies we tested chaining that included two compliance gaining procedures: the "but you are free" technique (BYAF) and social proof (SP). A total of 2204 passersby were approached in different countries (France, Tunisia, China and Moldavia). They were asked to donate money for cancer research with, respectively, a control formulation, a BYAF formulation, a SP formulation or a BYAF + SP formulation. Results indicate that chaining did not work because the BYAF + SP condition produced the same behavioral compliance as BYAF or SP separately (studies 1 and 2). Furthermore, we analyzed the participants' justifications after complying with or rejecting the request and the reasons were substantially the same under each condition (study 2). Failure to observe the chaining process is interpreted through theoretical explanations whereby BYAF and SP are antagonistic

Relevant microclimate for determining the development rate of malaria mosquitoes and possible implications of climate change

Background The relationship between mosquito development and temperature is one of the keys to understanding the current and future dynamics and distribution of vector-borne diseases such as malaria. Many process-based models use mean air temperature to estimate larval development times, and hence adult vector densities and/or malaria risk. Methods Water temperatures in three different-sized water pools, as well as the adjacent air temperature in lowland and highland sites in western Kenya were monitored. Both air and water temperatures were fed into a widely-applied temperature-dependent development model for Anopheles gambiae immatures, and subsequently their impact on predicted vector abundance was assessed. Results Mean water temperature in typical mosquito breeding sites was 4-6°C higher than the mean temperature of the adjacent air, resulting in larval development rates, and hence population growth rates, that are much higher than predicted based on air temperature. On the other hand, due to the non-linearities in the relationship between temperature and larval development rate, together with a marginal buffering in the increase in water temperature compared with air temperature, the relative increases in larval development rates predicted due to climate change are substantially less. Conclusions Existing models will tend to underestimate mosquito population growth under current conditions, and may overestimate relative increases in population growth under future climate change. These results highlight the need for better integration of biological and environmental information at the scale relevant to mosquito biology

Temporo-Spatial Dynamics of Event-Related EEG Beta Activity during the Initial Contingent Negative Variation

In the electroencephalogram (EEG), early anticipatory processes are accompanied by a slow negative potential, the initial contingent negative variation (iCNV), occurring between 500 and 1500 ms after cue onset over prefrontal cortical regions in tasks with cue-target intervals of about 3 s or longer. However, the temporal sequence of the distributed cortical activity contributing to iCNV generation remains unclear. During iCNV generation, selectively enhanced low-beta activity has been reported. Here we studied the temporal order of activation foci in cortical regions assumed to underlie iCNV generation using source reconstruction of low-beta (13–18 Hz) activity. During the iCNV, elicited by a cued simple reaction-time task, low-beta power peaked first (750 ms after cue onset) in anterior frontal and limbic regions and last (140 ms later) in posterior areas. This activity occurred 3300 ms before target onset and provides evidence for the temporally ordered involvement of both cognitive-control and motor-preparation processes already at early stages during the preparation for speeded action

Calculation of The Band Gap Energy and Study of Cross Luminescence in Alkaline-Earth Dihalide Crystals

The band gap energy as well as the possibility of cross luminescence processes in alkaline-earth dihalide crystals have been calculated using the ab initio Perturbed-Ion (PI) model. The gap is calculated in several ways: as a difference between one-electron energy eigenvalues and as a difference between total energies of appropriate electronic states of the crystal, both at the HF level and with inclusion of Coulomb correlation effects. In order to study the possibility of ocurrence of cross luminescence in these materials, the energy difference between the valence band and the upmost core band for some representative crystals has been calculated. Both calculated band gap energies and cross luminescence predictions compare very well with the available experimental results.Comment: LaTeX file containing 8 pages plus 1 postscript figure. Final version accepted for publication in The Journal of the Physical Society of Japan. It contains a more complete list of references, as well as a more detailed comparison with previous theoretical investigations on the subjec

Rapid and Reversible Recruitment of Early Visual Cortex for Touch

The loss of vision has been associated with enhanced performance in non-visual tasks such as tactile discrimination and sound localization. Current evidence suggests that these functional gains are linked to the recruitment of the occipital visual cortex for non-visual processing, but the neurophysiological mechanisms underlying these crossmodal changes remain uncertain. One possible explanation is that visual deprivation is associated with an unmasking of non-visual input into visual cortex.We investigated the effect of sudden, complete and prolonged visual deprivation (five days) in normally sighted adult individuals while they were immersed in an intensive tactile training program. Following the five-day period, blindfolded subjects performed better on a Braille character discrimination task. In the blindfold group, serial fMRI scans revealed an increase in BOLD signal within the occipital cortex in response to tactile stimulation after five days of complete visual deprivation. This increase in signal was no longer present 24 hours after blindfold removal. Finally, reversible disruption of occipital cortex function on the fifth day (by repetitive transcranial magnetic stimulation; rTMS) impaired Braille character recognition ability in the blindfold group but not in non-blindfolded controls. This disruptive effect was no longer evident once the blindfold had been removed for 24 hours.Overall, our findings suggest that sudden and complete visual deprivation in normally sighted individuals can lead to profound, but rapidly reversible, neuroplastic changes by which the occipital cortex becomes engaged in processing of non-visual information. The speed and dynamic nature of the observed changes suggests that normally inhibited or masked functions in the sighted are revealed by visual loss. The unmasking of pre-existing connections and shifts in connectivity represent rapid, early plastic changes, which presumably can lead, if sustained and reinforced, to slower developing, but more permanent structural changes, such as the establishment of new neural connections in the blind

Environmental variability in aquatic ecosystems: avenues for future multifactorial experiments

The relevance of considering environmental variability for understanding and predicting biological responses to environmental changes has resulted in a recent surge in variability-focused ecological research. However, integration of findings that emerge across studies and identification of remaining knowledge gaps in aquatic ecosystems remain critical. Here, we address these aspects by: (1) summarizing relevant terms of variability research including the components (characteristics) of variability and key interactions when considering multiple environmental factors; (2) identifying conceptual frameworks for understanding the consequences of environmental variability in single and multi-factorial scenarios; (3) highlighting challenges for bridging theoretical and experimental studies involving transitioning from simple to more complex scenarios; (4) proposing improved approaches to overcome current mismatches between theoretical predictions and experimental observations; and (5) providing a guide for designing integrated experiments across multiple scales, degrees of control, and complexity in light of their specific strengths and limitations