How the Ecdysozoan Changed Its Coat

External skeletons are found in a variety of animals, including arthropods and nematodes. Much remains to be learned about the process of replacing the exoskeleton (molting) during growth

An investigation into the feasibility, problems and benefits of re-engineering a legacy procedural CFD code into an event driven, object oriented system that allows dynamic user interaction

This research started with questions about how the overall efficiency, reliability and ease-of-use of Computational Fluid Dynamics (CFD) codes could be improved using any available software engineering and Human Computer Interaction (HCI) techniques. Much of this research has been driven by the difficulties experienced by novice CFD users in the area of Fire Field Modelling where the introduction of performance based building regulations have led to a situation where non CFD experts are increasingly making use of CFD techniques, with varying degrees of effectiveness, for safety critical research. Formerly, such modelling has not been helped by the mode of use, high degree of expertise required from the user and the complexity of specifying a simulation case. Many of the early stages of this research were channelled by perceived limitations of the original legacy CFD software that was chosen as a framework for these investigations. These limitations included poor code clarity, bad overall efficiency due to the use of batch mode processing, poor assurance that the final results presented from the CFD code were correct and the requirement for considerable expertise on the part of users. The innovative incremental re-engineering techniques developed to reverse-engineer, re-engineer and improve the internal structure and usability of the software were arrived at as a by-product of the research into overcoming the problems discovered in the legacy software. The incremental reengineering methodology was considered to be of enough importance to warrant inclusion in this thesis. Various HCI techniques were employed to attempt to overcome the efficiency and solution correctness problems. These investigations have demonstrated that the quality, reliability and overall run-time efficiency of CFD software can be significantly improved by the introduction of run-time monitoring and interactive solution control. It should be noted that the re-engineered CFD code is observed to run more slowly than the original FORTRAN legacy code due, mostly, to the changes in calling architecture of the software and differences in compiler optimisation: but, it is argued that the overall effectiveness, reliability and ease-of-use of the prototype software are all greatly improved. Investigations into dynamic solution control (made possible by the open software architecture and the interactive control interface) have demonstrated considerable savings when using solution control optimisation. Such investigations have also demonstrated the potential for improved assurance of correct simulation when compared with the batch mode of processing found in most legacy CFD software. Investigations have also been conducted into the efficiency implications of using unstructured group solvers. These group solvers are a derivation of the simple point-by-point Jaccobi Over Relaxation (JOR) and Successive Over Relaxation (SOR) solvers [CROFT98] and using group solvers allows the computational processing to be more effectively targeted on regions or logical collections of cells that require more intensive computation. Considerable savings have been demonstrated for the use of both static- and dynamic- group membership when using these group solvers for a complex 3-imensional fire modelling scenario. Furthermore the improvements in the system architecture (brought about as a result of software re-engineering) have helped to create an open framework that is both easy to comprehend and extend. This is in spite of the underlying unstructured nature of the simulation mesh with all of the associated complexity that this brings to the data structures. The prototype CFD software framework has recently been used as the core processing module in a commercial Fire Field Modelling product (called "SMARTFIRE" [EWER99-1]). This CFD framework is also being used by researchers to investigate many diverse aspects of CFD technology including Knowledge Based Solution Control, Gaseous and Solid Phase Combustion, Adaptive Meshing and CAD file interpretation for ease of case specification

Oncolog, Volume 36, Issue 01, January-March 1991

Decision making in critical illness: Who knows best? Successful Hodgkin\u27s disease treatment can also preserve reproductive function Chromosomes and cancerhttps://openworks.mdanderson.org/oncolog/1033/thumbnail.jp

The circadian clock gates Drosophila adult emergence by controlling the timecourse of metamorphosis

The daily rhythm of adult emergence of holometabolous insects is one of the first circadian rhythms to be studied. In these insects, the circadian clock imposes a daily pattern of emergence by allowing or stimulating eclosion during certain windows of time and inhibiting emergence during others, a process that has been described as “gating.” Although the circadian rhythm of insect emergence provided many of the key concepts of chronobiology, little progress has been made in understanding the bases of the gating process itself, although the term “gating” suggests that it is separate from the developmental process of metamorphosis. Here, we follow the progression through the final stages of Drosophila adult development with single-animal resolution and show that the circadian clock imposes a daily rhythmicity to the pattern of emergence by controlling when the insect initiates the final steps of metamorphosis itself. Circadian rhythmicity of emergence depends on the coupling between the central clock located in the brain and a peripheral clock located in the prothoracic gland (PG), an endocrine gland whose only known function is the production of the molting hormone, ecdysone. Here, we show that the clock exerts its action by regulating not the levels of ecdysone but that of its actions mediated by the ecdysone receptor. Our findings may also provide insights for understanding the mechanisms by which the daily rhythms of glucocorticoids are produced in mammals, which result from the coupling between the central clock in the suprachiasmatic nucleus and a peripheral clock located in the suprarenal gland.Fil: Brandon, Mark Thomas. Universidad de Valparaíso; Chile. University of Washington; Estados UnidosFil: Bustos González, Liliana. Universidad de Valparaíso; ChileFil: Cascallares, Maria Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; Argentina. Universidad de Valparaíso; ChileFil: Conejera, Felipe. Universidad de Valparaíso; ChileFil: Ewer, John. Universidad de Valparaíso; Chil

Trapped on the seashore, seaborne evacuation, impact of exposure to PM2.5: demonstration of the urbanEXODUS evacuation model

The 2021 wildfire season affected large communities in over ten countries around the Mediterranean basin consuming an area almost double the area burnt by wildfires over the past twelve years. In many cases, people were exposed to hazardous combustion products that caused mass multimodal evacuations, including pedestrian, vehicle, and seaborne evacuations as well as a large number of fatalities. Evacuation modelling can be used to better understand the processes involved, including the interactions between those processes. Such a model is urbanEXODUS, utilised during the final exercise (FSX3) for the European Commission’s Horizon 2020 project IN-PREP. The tool was used as part of a training platform for incident managers in collaborative response to large scale disasters. The scenario deployed during the FSX3, and presented in this work, involved a traffic accident and cascading effects that start a wildfire at a forested area, initiating a multi-modal evacuation of the local community. The model, able to simulate multi-modal evacuations, includes pedestrian and vehicle evacuation, and through the development of a flow model, a simplistic representation of boat evacuation. The model is also able to determine the effect of wildfire products using two different datasets that include (a) wildfire perimeter data and (b) smoke plume data that include PM2.5 concentration levels. The former limits the escape routes, causing engulfment and fatalities. The latter, through the development of a novel fractional dose model, determines the acute exposure of agents to PM2.5 in relation to the World Health Organisation (WHO) daily mean Air Quality Guidelines (AQG). The model demonstrates key evacuation performance results, including evacuation times, escape route usage and number and locations of fatalities. The results indicate that 6% of the entire population were unable to leave the area and are considered as fatalities. With regard to the evacuees, 69% utilised the road network to leave the area, while 31% utilised the seaborne evacuation. Exposure to PM2.5 was zero for 84% of the evacuees, while for 1% it was less than the AQG. However, 15% of the agents received a dosage of PM2.5 on average of 7.6 times the AQG (range 1.0 – 28.3, SD = 5.8). This level of exposure is expected to cause health problems including respiratory, cardiovascular and cerebrovascular disorders. The model offers detailed evacuation information that is practically impossible to obtain otherwise, allowing crisis managers to make risk-informed decisions when planning for a crisis

Trapped on the seashore, seaborne evacuation, and impact of exposure to PM2.5: Live demonstration of the urbanEXODUS large-scale evacuation model

Wildfires can trigger large-scale pedestrian, vehicle and seaborne evacuations, and cause injuries and fatalities. Evacuation models are employed to better understand the involved processes and their interactions. During the final exercise of the European Commission’s H2020 IN-PREP project, urbanEXODUS was used within a training platform, by incident managers, to aid their response to a simulated disaster. The scenario involved a traffic accident escalating to a wildfire, causing the local community to evacuate. The model combined pedestrian and vehicle evacuation, and through a flow model, a simplistic representation of boat evacuation. The effects of wildfire on escape routes and possible fatalities were evaluated using fire perimeter data. The development of a novel fractional dose model allowed the software to determine agents’ acute exposure to PM2.5, in relation to the WHO daily mean Air Quality Guidelines (AQG). The simulation results comprise key evacuation performance parameters including evacuation times, fatalities, and escape route usage. Results indicate that 6% of the population was unable to leave the area and are treated as fatalities. The road network and boats were used by 69% and 31% of the evacuees respectively. PM2.5 exposure was zero for 84% of the evacuees, and below the AQG, for 1%, while 15% received, on average, a dosage of 7.6 times the AQG (range 1.0 – 28.3, SD = 5.8), which may cause respiratory and cardiovascular disorders. The model offers detailed evacuation information that is practically impossible to obtain otherwise, allowing crisis managers to take risk-informed decisions when planning for a crisis

Inflight transmission of COVID-19 based on experimental aerosol dispersion data

Background: An issue of concern to the travelling public is the possibility of in-flight transmission of COVID-19 during long- and short-haul flights. The aviation industry maintains that the probability of contracting the illness is small based on reported cases, modelling and data from aerosol dispersion experiments conducted on-board aircraft. Methods: Using experimentally derived aerosol dispersion data for a B777–200 aircraft and a modified version of the Wells-Riley equation we estimate inflight infection probability for a range of scenarios involving quanta generation rate and face mask efficiency. Quanta generation rates were selected based on COVID-19 events reported in the literature while mask efficiency was determined from the aerosol dispersion experiments. Results: The MID-AFT cabin exhibits the highest infection probability. The calculated maximum individual infection probability (without masks) for a 2-hour flight in this section varies from 4.5% for the ‘Mild Scenario’ to 60.2% for the ‘Severe Scenario’ although the corresponding average infection probability varies from 0.1% to 2.5%. For a 12-hour flight, the corresponding maximum individual infection probability varies from 24.1% to 99.6% and the average infection probability varies from 0.8% to 10.8%. If all passengers wear face masks throughout the 12-hour flight, the average infection probability can be reduced by approximately 73%/32% for high/low efficiency masks. If face masks are worn by all passengers except during a one-hour meal service, the average infection probability is increased by 59%/8% compared to the situation where the mask is not removed. Conclusions: This analysis has demonstrated that while there is a significant reduction in aerosol concentration due to the nature of the cabin ventilation and filtration system, this does not necessarily mean that there is a low probability or risk of in-flight infection. However, mask wearing, particularly high-efficiency ones, significantly reduces this risk

Plug-and-play genetic access to drosophila cell types using exchangeable exon cassettes.

Genetically encoded effectors are important tools for probing cellular function in living animals, but improved methods for directing their expression to specific cell types are required. Here, we introduce a simple, versatile method for achieving cell-type-specific expression of transgenes that leverages the untapped potential of "coding introns" (i.e., introns between coding exons). Our method couples the expression of a transgene to that of a native gene expressed in the cells of interest using intronically inserted "plug-and-play" cassettes (called "Trojan exons") that carry a splice acceptor site followed by the coding sequences of T2A peptide and an effector transgene. We demonstrate the efficacy of this approach in Drosophila using lines containing suitable MiMIC (Minos-mediated integration cassette) transposons and a palette of Trojan exons capable of expressing a range of commonly used transcription factors. We also introduce an exchangeable, MiMIC-like Trojan exon construct that can be targeted to coding introns using the Crispr/Cas system.This work was supported by the Intramural Research Program of the National Institute of Mental Health (B.H.W.) and by grants from the Whitehall Foundation (C.J.P.), NIH (R01DC013070, C.J.P.), the Wellcome Trust (H.I. and M.L.), and the Sir Isaac Newton Trust, Cambridge (M.L.). J.E. was supported by FONDECYT #1141278 and the CINV, which is supported by the Millennium Scientific Initiative of the Ministerio de Economía, Fomento y Turismo. We thank the Bellen laboratory and the Drosophila Gene Disruption Project at Baylor College of Medicine, the Bloomington Stock Center (NIH P40OD018537), and Julie Simpson for fly lines. Thanks also to Aaron DiAntonio, Aaron Hsueh, and John Reinitz for antibodies and the NINDS Sequencing Core Facility for DNA sequencing. Finally, thanks to Sarah Naylor for technical help and Grace Gray, Herman Dierick, Koen Venken, and Hugo Bellen for comments on the manuscript and productive discussions.This is the final published version. It first appeared at http://www.ncbi.nlm.nih.gov/pubmed/25732830

Oxytocin and Vasopressin Receptor Gene Polymorphisms: Role in Social and Psychiatric Traits

Oxytocin (OXT) and arginine-vasopressin (AVP) are two phylogenetically conserved neuropeptides that have been implicated in a wide range of social behaviors. Although a large body of research, ranging from rodents to humans, has reported on the effects of OXT and AVP administration on affiliative and trust behaviors, and has highlighted the genetic contributions of OXT and AVP receptor polymorphisms to both social behaviors and to diseases related to social deficits, the consequences of peptide administration on psychiatric symptoms, and the impact of receptor polymorphisms on receptor function, are still unclear. Despite the exciting advances that these reports have brought to social neuroscience, they remain preliminary and suffer from the problems that are inherent to monogenetic linkage and association studies. As an alternative, some studies are using polygenic approaches, and consider the contributions of other genes and pathways, including those involving DA, 5-HT, and reelin, in addition to OXT and AVP; a handful of report are also using genome-wide association studies. This review summarizes findings on the associations between OXT and AVP receptor polymorphism, social behavior, and psychiatric diseases. In addition, we discuss reports on the interactions of OXT and AVP receptor genes and genes involved in other pathways (such as those of dopamine, serotonin, and reelin), as well as research that has shed some light on the impact of gene polymorphisms on the volume, connectivity, and activation of specific neural structures, differential receptor expression, and plasma levels of the OXT and AVP peptides. We hope that this effort will be helpful for understanding the studies performed so far, and for encouraging the inclusion of other candidate genes not explored to date

Fire safety risks of external living walls and implications for regulatory guidance in England

External living walls (LWs) have aesthetic and environmental appeal, but these characteristics must not compromise fire safety. A review of legislation indicates there are no specific fire regulations or test standards for LWs in England. Furthermore, the 2013 UK Green wall guidance document (GWGD) contradicts current guidance in Approved Document B (ADB) for certain categories of buildings, yet ADB cites GWGD as “best practice”. We suggest the recommended reaction to fire testing methodology for LW systems (single burning item (SBI) EN13823/ignitability EN ISO11925-2 tests) is inappropriate for assessing their fire performance. Despite some limitations, the BS8414 full-scale test could be used to assess LW installations. While not identified in the GWGD or specifically recommended within ADB as a suitable test method for LWs, it is arguably more appropriate than reduced scale SBI testing, primarily because it accommodates full LW modules with planting, and uses a more appropriate fire size. To reduce testing costs, we propose the use of CFD fire modelling, or a modified SBI test to identify candidate LW products likely to pass BS8414 testing. Given the inherent variable nature of LWs and their associated fire properties, LW maintenance is considered essential for on-going compliance with fire safety requirements