Maritime Navigation: Characterizing Collaboration in a High-Speed Craft Navigation Activity

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The Palamas Archaeological Project: A preliminary report of the 2022 fieldwork conducted by the ongoing Greek–Swedish archaeological field programme in Palamas, region of Karditsa, Thessaly

This paper presents the preliminary results from the 2022 fieldwork of the Palamas Archaeological Project, an ongoing Greek–Swedish collaboration in the region of Karditsa, Thessaly. Working over the course of two separate field seasons, the project team conducted aerial, architectural, fieldwalking, and geophysical surveys at a number of sites within the survey area, including at the important multi-phase fortified settlements at Metamorfosi and Vlochos. Limited excavations were also conducted at the latter site, producing new evidence for the Hellenistic and Early Byzantine phases of the ancient city, including a probable cemetery. The work continues to add to the knowledge of the archaeology of the region, highlighting the long and dynamic history of human habitation in western Thessaly

Role of a single noncoding nucleotide in the evolution of an epidemic African clade of Salmonella

Salmonella enterica serovar Typhimurium ST313 is a relatively newly emerged sequence type that is causing a devastating epidemic of bloodstream infections across sub-Saharan Africa. Analysis of hundreds ofSalmonellagenomes has revealed that ST313 is closely related to the ST19 group ofSTyphimurium that cause gastroenteritis across the world. The core genomes of ST313 and ST19 vary by only ∼1,000 SNPs. We hypothesized that the phenotypic differences that distinguish AfricanSalmonellafrom ST19 are caused by certain SNPs that directly modulate the transcription of virulence genes. Here we identified 3,597 transcriptional start sites of the ST313 strain D23580, and searched for a gene-expression signature linked to pathogenesis ofSalmonellaWe identified a SNP in the promoter of thepgtEgene that caused high expression of the PgtE virulence factor in AfricanS.Typhimurium, increased the degradation of the factor B component of human complement, contributed to serum resistance, and modulated virulence in the chicken infection model. We propose that high levels of PgtE expression by AfricanSTyphimurium ST313 promote bacterial survival and dissemination during human infection. Our finding of a functional role for an extragenic SNP shows that approaches used to deduce the evolution of virulence in bacterial pathogens should include a focus on noncoding regions of the genome

The Vlochos Archaeological Project: Report on the 2016– 2018 seasons of Greek-Swedish archaeological work at Vlochos, Thessaly

The Vlochos Archaeological Project (2016–2018) was a Greek-Swedish archaeological investigation of the remains of the ancient urban site at Vlochos in western Thessaly, Greece. Employing a wide array of noninvasive methods, the project succeeded in completely mapping the visible remains, which had previously not been systematically investigated. The extensive remains of multi-period urban fortifications, a ClassicalHellenistic city, a Roman town, and a Late Antique fortress were identified, evidence of the long history of habitation on this site. Since comparatively little fieldwork has been conducted in the region, the results significantly increase our knowledge of the history and archaeology of Thessaly

Stealth-Based Path Planning using Corridor Maps

A relatively new area within the field of path planning deals with computing a stealthy path for a character moving in a virtual environment. Besides efficiently obtaining a path that is collision-free, short and smooth, the added difficulty is that the path must have little or no exposure to observers. We propose a new algorithm for computing such a path in the plane, and show that real-time performance can be achieved

Status of young-of-the-year brown trout (Salmo trutta fario) in Swiss streams: factors influencing YOY trout recruitment

As part of the Swiss Fischnetz project (network for declining fish yields in Switzerland) studies were carried out to investigate the decline in catches of brown trout . Insufficient YOY ( young-of-the-year ) recruitment of brown trout due to different abiotic and/or biotic factors was hypothesized as a potential cause of this decline. Quantitative assessments of fish ecology parameters and habitat measurements were carried out at 97 river sites over a two-year period. The main objectives of this study were to document the occurrence and abundance of naturally reproduced YOY trout and to develop an understanding of environmental factors responsible for the observed YOY density. A general linear model (GLM) was used to analyse the influence of selected environmental abiotic and biotic parameters on YOY density. Successful recruitment of YOY trout was observed in all but three of the sites studied. Abundance was correlated with abiotic and biotic factors , such as river width, slope, altitude, substratum condition, and the occurrence of proliferative kidney disease (PKD). The results highlight the importance of small streams for natural YOY recruitment of brown trout and their function as a source of individuals for downstream river sections

Assessing the decline of brown trout (Salmo trutta) in Swiss rivers using a Bayesian probability network

A Bayesian probability network has been developed to integrate the various scientific findings of an interdisciplinary research project on brown trout and their habitat in Switzerland. The network is based on a dynamic, age-structured population model, which is extended to include the effect of natural and anthropogenic influence factors. These include gravel bed conditions, water quality, disease rates, water temperature, habitat conditions, stocking practices, angler catch and flood frequency. Effect strength and associated uncertainty are described by conditional probability distributions. These conditional probabilities were developed using experimental and field data, literature reports, and the elicited judgment of involved scientists. The model was applied to brown trout populations at 12 locations in four river basins. Model testing consisted of comparing predictions of juvenile and adult density under current conditions to the results of recent population surveys. The relative importance of the various influence factors was then assessed by comparing various model scenarios, including a hypothetical reference condition. A measure of causal strength was developed based on this comparison, and the major stress factors were analyzed according to this measure for each location. We found that suboptimal habitat conditions are the most important and ubiquitous stress factor and have impacts of sufficient magnitude to explain the reduced fish populations observed in recent years. However, other factors likely contribute to the declines, depending on local conditions. The model developed in this study can be used to provide these site-specific assessments and predict the effect of candidate management measures. (c) 2005 Elsevier B.V. All rights reserved

Maritime Navigation: Characterizing Collaboration in a High-Speed Craft Navigation Activity

Communication is an important factor in teamwork and collaboration in safety-critical systems. Operating a safety-critical system such as a military vessel requires maintaining high levels of safety. In maritime navigation, communication is key and collaboration as a team is paramount for safety during navigation. Characterizing this is essential for training and bridge design purposes. Characterizing requires objective tools in addition to visual observation of the navigational exercise. Eye-trackers can fill this gap. Eye-trackers enable measurement of eye movements and dilation measures of the pupil in real time. This can help locate design issues and assist designing training paradigms. In this study two eye-trackers were used to measure joint vision of two navigator simultaneously. Through data of visual attention communication patterns can be characterized with greater richness than just visual observation. As for this case study, in an simulator at the Royal Norwegian Naval Academy in Bergen (Norway), understanding the kind of communication and finding a way to formulate the collaboration will help to characterize communication pattern as a first attempt. This study builds up upon a previous study that improved an off the shelf eye-tracker through hardware additions and software enhancements to accurately measure pupil dilation despite changing ambient light. This study is expected to be a key landmark study that shows the potential of objective tools such as eye-trackers to characterize communication in safety critical systems such as a high-speed navigational environment

Regional air pollution over Malaysia

International audienceDuring the SHIVA (Stratospheric Ozone: Halogen Impacts in a Varying Atmosphere) campaign in Nov. and Dec. 2011 a number of polluted air masses were observed in the marine and terrestrial boundary layer (0 – 2 km) and in the free troposphere (2 – 12 km) over Borneo/Malaysia. The measurements include isoprene, CO, CO2, CH4, N2O, NO2, SO2 as primary pollutants, O3 and HCHO as secondary pollutants, and meteorological parameters. This set of trace gases can be used to fingerprint different sources of local and regional air pollution (e.g., biomass burning and fossil fuel burning, gas flaring on oil rigs, emission of ships and from urban areas, volcanic emissions, and biogenic emissions). Individual sources and location can be identified when the measurements are combined with a nested-grid regional scale chemical and meteorological model and lagrangian particle dispersion model (e.g., CCATT-BRAMS and FLEXPART). In the case of the former, emission inventories of the primary pollutants provide the basis for the trace gas simulations. In this region, the anthropogenic influence on air pollution seems to dominate over natural causes. For example, CO2 and CH4 often show strong correlations with CO, suggesting biomass burning or urban fossil fuel combustion dominates the combustion sources. The study of the CO/CO2 and CH4/CO ratios can help separate anthropogenic combustion from biomass burning pollution sources. In addition, these ratios can be used as a measure of combustion efficiency to help place the type of biomass burning particular to this region within the wider context of fire types found globally. On several occasions, CH4 enhancements are observed near the ocean surface, which are not directly correlated with CO enhancements thus indicating a non-combustion-related CH4 source. Positive correlations between SO2 and CO show the anthropogenic influence of oil rigs located in the South China Sea. Furthermore, SO2 enhancements are observed without any increase in CO, indicating possible volcanic emissions from the Indonesian islands to the South and East and the Philippines to the North East. The regional pollution seems to be influenced by emissions from Singapore, Philippines, Indonesia and Peninsula Malaysia, and on occasion by anthropogenic emissions from Thailand, Vietnam, Australia, and China