Why are Orlicz spaces useful for Statistical Physics?

We review a new formalism based on Orlicz spaces for the description of large regular statistical systems. Our presentation includes both classical and quantum systems. The presented approach has the advantage that statistical mechanics is much better settled.Comment: 11 pages. arXiv admin note: text overlap with arXiv:1302.346

On applications of Orlicz Spaces to Statistical Physics

We present a new rigorous approach based on Orlicz spaces for the description of the statistics of large regular statistical systems, both classical and quantum. This approach has the advantage that statistical mechanics is much better settled. In particular, a new kind of renormalization leading to states having a well defined entropy function is presented.Comment: 20 page

Quantum Fokker-Planck Dynamics

The Fokker-Planck equation is a partial differential equation which is a key ingredient in many models in physics. This paper aims to obtain a quantum counterpart of Fokker-Planck dynamics, as a means to describing quantum Fokker-Planck dynamics. Given that relevant models relate to the description of large systems, the quantization of the Fokker-Planck equation should be done in a manner that respects this fact, and is therefore carried out within the setting of non-commutative analysis based on general von Neumann algebras. Within this framework we present a quantization of the generalized Laplace operator, and then go on to incorporate a potential term conditioned to noncommutative analysis. In closing we then construct and examine the asymptotic behaviour of the corresponding Markov semigroups. We also present a noncommutative Csiszar-Kullback inequality formulated in terms of a notion of relative entropy, and show that for more general systems, good behaviour with respect to this notion of entropy ensures similar asymptotic behaviour of the relevant dynamics.Comment: The final version submitted to AHP. A brief account of applied quantization as well as the comprehensive description of closability of quantum Laplacian is adde

Micro-CT investigation of urea crystal structures for frost analysis

Frost formation poses a significant challenge to the design and efficiency of air-source evaporator units. To model frost formation, a detailed understanding of the evolving three-dimensional microstructures that influence thermal and mass transport properties is essential. However, direct measurement of frost microstructures remains challenging. This study demonstrates that Micro-CT, combined with finite-element modelling, is a viable method for evaluating transport properties in complex microstructures. Using urea mushy layers as a stable, non-melting analogue, we successfully validated the methodology by resolving microstructural influences on thermal conductivity and mass diffusivity. Our results highlight the significant role of structural complexity in transport behaviour, with ‘simple’ and ‘complex’ formations influencing heat and mass transfer differently. Deviations of at least 26.6 % between measured properties and predictions from empirical bulk-property models confirm that conventional approaches fail to capture the effects of structural heterogeneity. While these findings do not directly translate to frost formation, the validated methodology offers a foundation for improving frost prediction models by incorporating high-resolution structural data, ultimately enhancing the accuracy of thermal system designs in frost-prone environments.</p

One-carbon metabolism in cancer

Cells require one-carbon units for nucleotide synthesis, methylation and reductive metabolism, and these pathways support the high proliferative rate of cancer cells. As such, anti-folates, drugs that target one-carbon metabolism, have long been used in the treatment of cancer. Amino acids, such as serine are a major one-carbon source, and cancer cells are particularly susceptible to deprivation of one-carbon units by serine restriction or inhibition of de novo serine synthesis. Recent work has also begun to decipher the specific pathways and sub-cellular compartments that are important for one-carbon metabolism in cancer cells. In this review we summarise the historical understanding of one-carbon metabolism in cancer, describe the recent findings regarding the generation and usage of one-carbon units and explore possible future therapeutics that could exploit the dependency of cancer cells on one-carbon metabolism

Antecedent bedrock control on the sediment-starved continental shelf of south/central Namibia

The Namibian inner continental shelf immediately north of the Orange River delta is sediment-poor, dominated by outcrop of metamorphic basement with a scarcity of sandy cover. Using a combination of high and very-high resolution geophysical tools and drill cores, an examination of the evolution of the inner shelf stratigraphy and geomorphology shows persistent antecedent bedrock controls throughout the Pleistocene.The bedrock of the inner shelf comprises schists, in places overlain by Eocene sandstones, over which a subaerial unconformity (H1) formed in the late Oligocene. H1 was repeatedly re-occupied during succeeding transgressive/regressive cycles, creating a backstop for erosion/sedimentation and creating a repeating topography on which transgressions took place. Apart from localised development of Miocene phosphatic limestones, little sediment has since accumulated. Large-scale karst weathering of the limestones reflects several periods of subaerial exposure most recently during the Quaternary lowstands of sea level including MIS 2 and 1.Thin Quaternary cover, housed within depressions on the H1 surface is predominantly preserved in the lee of bedrock ridges, behind which shallow and occasionally hypersaline lagoonal conditions developed. These preserved back-barrier sedimentary sequences developed post-MIS 5 (previous phases were either eroded/weathered or not deposited). Dolomite precipitation occurred when sea-level stabilised at −75 m 37,000 cal BP and restricted lagoonal conditions prevailed.Currently, there are very limited MIS 2/1 deposits preserved above H1. The absence of thick sand cover, adjacent to and downdrift of the Orange River delta, suggests that the onshore diversion of sand that currently supplies the Namib Sand Sea also operated during lower sea levels, related to the bedrock control and lack of accommodation in surface H1. This persistent onshore diversion of deltaic sediment throughout the Quaternary has implications for sediment source as well as budget calculations for the Namib Sand Sea

Errors in drug administration by anaesthetists in public hospitals in the Free State

Objective. To investigate errors in administering drugs by anaesthetists working in public hospitals in the Free State province. Methods. Anonymous questionnaires were distributed to doctors performing anaesthesia in public hospitals in the Free State, i.e. 188 doctors at 22 public sector hospitals. Outcomes included demographic information on respondents, information regarding the administration of anaesthetics, reporting of errors, and the occurrence of errors during anaesthesia. Results. The response rate was 46.3%; 48.8% were medical officers, and 39.3% of participants were involved in at least one event of erroneous drug administration. Registrars and specialists reported the most errors. Most events were of no clinical significance, caused no permanent harm to patients, and most commonly involved fentanyl and suxamethonium. Of the respondents, 23.8% indicated that they were aware of a South African standard for colour-coding syringe labels, and 92.9% indicated that they would report anaesthetic errors if a single reporting agency for such events existed. Conclusions. More than a third of participating anaesthetists were involved in a drug error at some stage in their practice. Preventive systems and precautionary measures should be put in place to reduce drug administration errors

222Rn calibrated mercury fluxes from terrestrial surfaces of southern Africa derived from observations at Cape Point, South Africa

Gaseous elemental mercury (GEM) and 222Rn, a radioactive gas of primarily terrestrial origin with a half-life of 3.8 days, have been measured simultaneously at Cape Point, South Africa, since March 2007. Between March 2007 and December 2009 altogether 59 events with high 222Rn concentrations were identified. GEM correlated with 222Rn in 41 of the events and was constant during the remaining events without significant correlation. The average GEM/222Rn emission ratio of all events was -0.0047 ± 0.0054 pg mBq-1, with ± 0.0054 being the standard error of the average. With an emission rate of 1.1 222Rn atoms cm-2 s-1 and a correction for the transport duration, this emission ratio corresponds to a radon calibrated flux of about -0.53 ± 0.62 ng m-2 h-1 which is statistically not distinguishable from zero. With wet deposition, which is not included in this estimate, the terrestrial surface of southern Africa appears to be a net mercury sink. © Owned by the authors, published by EDP Sciences, 201

222Rn-calibrated mercury fluxes from terrestrial surface of southern Africa

Gaseous elemental mercury (GEM) and 222Rn, a radioactive gas of primarily terrestrial origin with a half-life of 3.8 days, have been measured simultaneously at Cape Point, South Africa, since March 2007. Between March 2007 and December 2011, altogether 191 events with high 222Rn concentrations were identified. GEM correlated with 222Rn in 94 of the events and was constant during almost all the remaining events without significant correlation. The average GEM / 222Rn flux ratio of all events including the non-significant ones was −0.0001 with a standard error of ±0.0030 pg mBq−1. Weighted with the event duration, the average GEM / 222Rn flux ratio was −0.0048 ± 0.0011 pg mBq−1. With an emission rate of 1.1 222Rn atoms cm−2 s−1 and a correction for the transport time, this flux ratio corresponds to a radon-calibrated flux of about −0.54 ng GEM m−2 h−1 with a standard error of ±0.13 ng GEM m−2 h−1 (n = 191). With wet deposition, which is not included in this estimate, the terrestrial surface of southern Africa seems to be a net mercury sink of about −1.55 ng m−2 h−1. The additional contribution of an unknown but presumably significant deposition of reactive gaseous mercury would further increase this sink.© 2013, European Geosciences Unio

Sports coaching and the law of negligence: implications for coaching practice

The ordinary principles of the law of negligence are applicable in the context of sport, including claims brought against volunteer and professional coaches. Adopting the perspective of the coach, this article intends to raise awareness of the emerging intersection between the law of negligence and sports coaching, by utilising an interdisciplinary analysis designed to better safeguard and reassure coaches mindful of legal liability. Detailed scrutiny of two cases concerning alleged negligent coaching, with complementary discussion of some of the ethical dilemmas facing modern coaches, reinforces the legal duty and obligation of all coaches to adopt objectively reasonable and justifiable coaching practices when interacting with athletes. Problematically, since research suggests that some coaching practice may be underpinned by ‘entrenched legitimacy’ and ‘uncritical inertia’, it is argued that coach education and training should place a greater emphasis on developing a coach’s awareness and understanding of the evolving legal context in which they discharge the duty of care incumbent upon them