Occurrence of Kanamycin-Resistant Bacteria Relative to Anthropogenic Pollution Along Richland Creek in Nashville, TN​

The overuse of antibiotics has caused an increase in antibiotic-resistant (AR) bacteria, which is a serious public health concern. Previous studies showed a significant correlation between anthropogenic pollution and AR bacteria. This project aims to identify AR bacteria in Richland Creek relative to local anthropogenic pollution. Water samples were collected at four locations along Richland Creek in Nashville, Tennessee. Bacteria resistant to the antibiotic kanamycin were isolated from the water samples, identified to genera using DNA barcoding, and compared among the sites. We expect to see a greater abundance and diversity of kanamycin-resistant bacteria closer to the end than near the head of the creek. This research project can help describe the diversity of AR bacteria species present in the stream in different areas of Nashville and has public health consequences if the disparities in the distribution of AR bacteria correlate to human activity and/or socioeconomic differences along the stream

Toward a decompositional and incremental approach to diagnosis of dynamic systems from timed observations

International audienceIt is now well-known that the size of the model is the bottleneck when using model-based approaches to diagnose complex systems. To answer this problem, decompositional and multi modelling approaches have been proposed. In this paper, we propose a multi-modelling method called TOM4D (Timed Observations Modelling for Diagnosis) able to cope with dynamic aspects. It relies on four models: perception, structural, functional and behaviour models. The behaviour model is described through system component models as a set of component behaviour models and the global diagnosis is computed from the component diagnoses (also called local diagnoses). Another problem, which is far less considered, is the size of the diagnosis itself. However, it can also be huge enough, especially when dealing with dynamic system. To solve this problem, we propose in this paper to use The Timed Observation Theory. In this context, we characterize the diagnosis using TOM4D and the timed observation theory. We show their relevance to get a tractable representation of diagnosis. To illustrate the impact on the diagnosis size, experimental results on a hydraulic example are given

Proposition d'une approche de modélisation et de diagnostic du comportement des barrages

National audienceCet article présente le développement d'une méthode de diagnostic basée sur une approche multi-modèles pour le diagnostic du comportement des barrages. Trois modèles sont décrits : un modèle structurel, un modèle comportemental et un modèle fonctionnel. Le contexte particulier des barrages et notamment le fait que les modèles numériques sont peu nombreux nous a amenés à proposer un modèle structurel et un modèle comportemental originaux. La définition d'un modèle structurel unique pour l'ensemble des composants reposant sur un faible nombre de variables permet de concilier efficacité calculatoire et efficacité du diagnostic. Le diagnostic restitue plusieurs éléments : les composants, process et phénomènes impliqués mais également une identification des causes et une analyse des mécanismes au cours du temps. / This article presents the development of a diagnostic method for dam behaviour. This method is based on multimodelling reasoning. Three models are described: a structural model, a behavioural model and a functional model. The scarcity of numerical models leads us to propose original structural and behavioural models. A single structural model relying on few variables is defined for all the components. It allows a computing efficiency along with a reliable diagnosis. The diagnosis produces several elements: the components, processes and phenomena involved in the faulty behaviour, an identification of the causes of the faulty behaviour and an analysis of mechanisms through time

Process diagnosis with timed observation

International audienceIn this paper we propose the use of the Timed Observation theory as a powerful frameworks for model-based diagnosis. In fact, they provide a global formalism for modelling a dynamic system (TOM4D), for characterizing and computing diagnoses of the system under investigation

Modelling and diagnosis of dynamic systems from timed observations

International audienceThis paper proposes the use of the Timed Observation theory as a powerful framework for model-based diagnosis. In fact, this theory provides a global formalism for modelling a dynamic system (TOM4D), for characterizing and computing diagnoses of the system under investigation

Burdigalian deposits of the Santa Cruz Formation in the Sierra Baguales, Austral (Magallanes) Basin: Age, depositional environment and vertebrate fossils

Indexación: Web of Science; Scielo.ABSTRACT. A succession of marine and continental strata on the southern flank of Cerro Cono in the Sierra Baguales, northeast of Torres del Paine, can be correlated with stratigraphic units exposed along the southern border of the Lago Argentino region in Santa Cruz Province, Argentina. These include the Estancia 25 de Mayo Formation and the basal part of the Santa Cruz Formation. The lithological correlation is also confirmed by detrital zircon ages (maximum age of 18.23±0.26 Ma) and a rich assemblage of terrestrial vertebrate fossils, biostratigraphically equivalent to a postColhuehuapian, pre-Santacrucian South American Land Mammal Age (SALMA) fauna, suggesting a range of 19 to 17.8 Ma. Similar ages have been obtained from the basal part of the Santa Cruz Formation at Estancia Quién Sabe in southwestern Argentina, supporting the assumption of a regional continuity between these deposits. A measured lithostratigraphic column is presented and the depositional environment is interpreted as a coastal plain with small, meandering rivers and ephemeral floodplain lakes. The sedimentation coincides with intensified uplift of the Patagonian Andes during the ‘Quechua Phase’ of Andean tectonism, which is reflected by a change in paleocurrent directions from northwest to east-northeast. Keywords: Burdigalian, Santa Cruz Formation, Santacrucian SALMA, ‘Notohippidian’ fauna, Meandering rivers.RESUMEN. Una sucesión de estratos marinos y continentales en el flanco meridional del cerro Cono, en la sierra Baguales, al noreste de Torres del Paine, se correlaciona con estratos al sur de la región de lago Argentino en la Provincia de Santa Cruz, República Argentina. Estas unidades incluyen la Formación Estancia 25 de Mayo y la parte basal de la Formación Santa Cruz. La correlación litológica es, además, confirmada por datación de circones detríticos (edad máxima de 18,23±0,26 Ma) y un variado ensamble de vertebrados fósiles terrestres de edad post-Colhuehuapense a pre-Santacrucense en la escala de Edades Mamífero Sudamericanas (EMAS), con un rango temporal de entre 19 a 17,8 Ma. Edades similares han sido reportadas para la parte basal de la Formación Santa Cruz, en estancia Quién Sabe, en el suroeste de Argentina, ratificando la continuidad regional entre estos depósitos. Se presenta una columna estratigráfica y se interpreta el ambiente de depositación como una llanura costera con pequeños ríos sinuosos y lagos efímeros. La edad de sedimentación coincide con el solevantamiento de los Andes Patagónicos durante la 'Fase Quechua', lo que se ve reflejado por un cambio en la dirección de las paleocorrientes desde el noroeste hacia el este-noreste.http://ref.scielo.org/csxwd

Transgender Resiliency: A Comparison of Transgender and Cisgender Therapy Clients’ Family Functioning and Psychological Symptomology

Existing literature often suggests transgender people face increased vulnerabilities in comparison to cisgender people and poorer mental and physical health outcomes. However, studies are increasingly exploring resilience of transgender people and factors contributing to positive coping. The current study compared transgender to cisgender clients at a University-based couple and family therapy center on self-reported psychological symptomology and family functioning. Transgender individuals did not differ significantly from cisgender individuals on family functioning, however transgender individuals reported significantly fewer symptoms on all twelve subscales of psychological symptomology, despite lower income and lower levels of education. Results suggest transgender individuals may develop unique traits or processes allowing them to more effectively cope with stressors, supporting the presence of resiliency in this population

Molecular Communication Channel Modelling in FPGA Technology

Molecular Communication (MC) is a new paradigm for communication processes with a variety of applications such as health care and industrial sectors. The rapid development of MC, with the support of testbeds and simulators, requires scalable modeling tools. In this paper, we propose a field-programmable gate array (FPGA) design-based approach for the emission, diffusion, and reception of molecules. Results exhibit a close correspondence to state of the art analytical modeling of MC processes

High-Frequency Trading on Decentralized On-Chain Exchanges

Decentralized exchanges (DEXs) allow parties to participate in financial markets while retaining full custody of their funds. However, the transparency of blockchain-based DEX in combination with the latency for transactions to be processed, makes market-manipulation feasible. For instance, adversaries could perform front-running -- the practice of exploiting (typically non-public) information that may change the price of an asset for financial gain. In this work we formalize, analytically exposit and empirically evaluate an augmented variant of front-running: sandwich attacks, which involve front- and back-running victim transactions on a blockchain-based DEX. We quantify the probability of an adversarial trader being able to undertake the attack, based on the relative positioning of a transaction within a blockchain block. We find that a single adversarial trader can earn a daily revenue of over several thousand USD when performing sandwich attacks on one particular DEX -- Uniswap, an exchange with over 5M USD daily trading volume by June 2020. In addition to a single-adversary game, we simulate the outcome of sandwich attacks under multiple competing adversaries, to account for the real-world trading environment

Dark halo baryons not in ancient halo white dwarfs

Having ruled out the possibility that stellar objects are the main contributor of the dark matter embedding galaxies, microlensing experiments cannot exclude the hypothesis that a significant fraction of the Milky Way dark halo might be made of MACHOs with masses in the range 0.5-0.8 \msun. Ancient white dwarfs are generally considered the most plausible candidates for such MACHOs. We report the results of a search for such white dwarfs in a proper motion survey covering a 0.16 sqd field at three epochs at high galactic latitude, and 0.938 sqd at two epochs at intermediate galactic latitude (VIRMOS survey), using the CFH telescope. Both surveys are complete to I = 23, with detection efficiency fading to 0 at I = 24.2. Proper motion data are suitable to separate unambiguously halo white dwarfs identified by belonging to a non rotating system. No candidates were found within the colour-magnitude-proper motion volume where such objects can be safely discriminated from any standard population as well as from possible artefacts. In the same volume, we estimate the maximum white dwarf halo fraction compatible with this observation at different significance levels if the halo is at least 14 gigayears old and under different ad hoc initial mass functions. Our data alone rules out a halo fraction greater than 14% at 95% confidence level. Combined with two previous investigations exploring comparable volumes pushes the limit below 4 % (95% confidence level) or below 1.3% (64% confidence), this implies that if baryonic dark matter is present in galaxy halos, it is not, or it is only marginally in the form of faint hydrogen white dwarfs.Comment: accepted in Astronomy and Astrophysics (19-05-2004