2,956 research outputs found

    Signatures of impulsive localized heating in the temperature distribution of multi-stranded coronal loops

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    We study the signatures of different coronal heating regimes on the differential emission measure (DEM) of multi-stranded coronal loops by means of hydrodynamic simulations. We consider heating either uniformly distributed along the loops or localized close to the chromospheric footpoints, in both steady and impulsive conditions. Our simulations show that condensation at the top of the loop forms when the localized heating is impulsive with a pulse cadence time shorter than the plasma cooling time, and the pulse energy is below a certain threshold. A condensation does not produce observable signatures in the global DEM structure. Conversely, the DEM coronal peak is found sensitive to the pulse cadence time. Our simulations can also give an explanation of the warm overdense and hot underdense loops observed by TRACE, SOHO and Yohkoh. However, they are unable to reproduce both the transition region and the coronal DEM structure with a unique set of parameters, which outlines the need for a more realistic description of the transition region.Comment: 31 pages, 7 figure

    Participatory Approach to Planning Urban Resilience to Climate Change: Brescia, Genoa, and Matera—Three Case Studies from Italy Compared

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    Urban resilience must consider the ability of cities to cope with the effects of climate change. Community awareness raising and sustainable urban drainage systems (SUDs) are often mentioned in the literature as effective adaptation actions while the success of these solutions is highly context-dependent and improved planning procedures are urgently needed. In this framework, the URCA! project represents a good practice aiming to strengthen the resilience of urban areas by promoting the implementation of SUDs in territorial planning. The main objective of the present research deals with the role of participation in promoting the use of SUDs and their uptake in town planning and land management involving local communities, students, experts, local authorities, and enterprises. To this end, the research adopts a participatory approach to SUDs urban planning for three case studies in Italy selected under the criterion of maximum variation (Brescia, Genoa, and Matera). For the three case studies, participatory approaches are at different stages of development thus requiring appropriate ways of interacting and resulting in different impacts on decisions. Preliminary results, drivers, and barriers in the application of the participatory approach are discussed and compared in order to bring innovation into planning practices, stimulating a revision of typical governance mechanisms

    Velocity measurements for a solar active region fan loop from Hinode/EIS observations

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    The velocity pattern of a fan loop structure within a solar active region over the temperature range 0.15-1.5 MK is derived using data from the EUV Imaging Spectrometer (EIS) on board the Hinode satellite. The loop is aligned towards the observer's line-of-sight and shows downflows (redshifts) of around 15 km/s up to a temperature of 0.8 MK, but for temperatures of 1.0 MK and above the measured velocity shifts are consistent with no net flow. This velocity result applies over a projected spatial distance of 9 Mm and demonstrates that the cooler, redshifted plasma is physically disconnected from the hotter, stationary plasma. A scenario in which the fan loops consist of at least two groups of "strands" - one cooler and downflowing, the other hotter and stationary -- is suggested. The cooler strands may represent a later evolutionary stage of the hotter strands. A density diagnostic of Mg VII was used to show that the electron density at around 0.8 MK falls from 3.2 x 10^9 cm^-3 at the loop base, to 5.0 x 10^8 cm^-3 at a projected height of 15 Mm. A filling factor of 0.2 is found at temperatures close to the formation temperature of Mg VII (0.8 MK), confirming that the cooler, downflowing plasma occupies only a fraction of the apparent loop volume. The fan loop is rooted within a so-called "outflow region" that displays low intensity and blueshifts of up to 25 km/s in Fe XII 195.12 A (formed at 1.5 MK), in contrast to the loop's redshifts of 15 km/s at 0.8 MK. A new technique for obtaining an absolute wavelength calibration for the EIS instrument is presented and an instrumental effect, possibly related to a distorted point spread function, that affects velocity measurements is identified.Comment: 42 pages, 15 figures, submitted to Ap

    Extending Immunity for Drug Overdoses

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    The Tennessee Code 63-1-156 provides immunity to those who suffer from a drug overdose that seek medical assistance, only for the first overdose. After the first overdose, individuals who seek medical assistance do not receive immunity and are subject to criminal charges. Over the past 5 years, drug overdose deaths have increased significantly and in 2021 3,814 Tennesseans died from a drug overdose. In addition, individuals incarcerated for drug-related offenses make up about 20% of the state’s prison population. The state of Tennessee has had a significant increase in drug abuse rates, leading to a rise in overdose deaths and incarceration rates. HB0075 and SB0256, sponsored by Representative William Lamberth and Senator Jack Johnson, extend criminal immunity for those suffering from drug overdose and seeking medical assistance, whether the first or any overdose. This legislation recognizes data indicating that people who have overdosed once are more likely to overdose again (CDC, 2022). These bills recognize the importance of providing individuals with the necessary protection to seek medical assistance without fear of legal repercussions for every overdose. By shifting the focus from criminalizing drug use to providing immunity and assistance for every overdose, HB0075 and SB0256 align with the NASW values social justice and dignity and worth of the person. The bills aim to protect individuals\u27 dignity by providing immunity to those who seek medical assistance for an overdose, and they promote social justice by recognizing drug use as a public health issue and providing support and assistance to individuals who suffer from drug overdose. This paper will explore these bills and their potential to have a positive impact on the social welfare issue of drug use

    Potential of two Metschnikowia pulcherrima (yeast) strains for in vitro biodegradation of patulin.

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    Patulin contamination of apple and other fruit-based foods and beverages is an important food safety issue, as consumption of these commodities throughout the world is great. Studies are therefore necessary to reduce patulin levels to acceptable limits or undetectable levels to minimize toxicity. This study was undertaken to investigate the efficacy of two Metschnikowia pulcherrima strains (MACH1 and GS9) on biodegradation of patulin under in vitro conditions. These yeast strains were tested for their abilities to degrade patulin in liquid medium amended with 5, 7.5, 10, and 15 μg/ml patulin and a yeast cell concentration of 1 × 10(8) cells per ml at 25°C. Of the two strains tested, MACH1 completely (100%) reduced patulin levels within 48 h, and GS9 within 72 h, at all concentrations of patulin. MACH1 effectively degraded the patulin within 24 h by 83 to 87.4%, and GS9 by 73 to 75.6% at 48 h, regardless of concentration. Patulin was not detected in yeast cell walls. This indicates that yeast cell walls did not absorb patulin, and that they completely degraded the toxin. Patulin had no influence on yeast cell concentration during growth. Therefore, these yeast strains could potentially be used for the reduction of patulin in naturally contaminated fruit juices. To our knowledge, this is the first report regarding the potential of M. pulcherrima strains for patulin biodegradation

    Ontogenetic Shifts in Resource Allocation: Colour Change and Allometric Growth of Defensive and Reproductive Structures in the Caribbean Spiny Lobster Panulirus argus

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    Resource allocation theory predicts a disproportionately large allocation of resources to defensive structures during early ontogeny in organisms that are subject to more intense predation at smaller than at larger body sizes. We tested this prediction on the Caribbean spiny lobster Panulirus argus, which exhibits a negative relationship between predation risk and body size with a high natural mortality of smaller individuals. Independent allometric growth analyses demonstrated that numerous defensive structures (e.g. orbital horns, segments supporting the antenna, the tail fan) display negative allometric growth throughout ontogeny. We interpret these findings as lobsters investing disproportionately more resources to defensive structures when small to improve survivorship. Similarly, we observed an ontogenetic shift in lobster colour pattern; small individuals (\u3c23mm carapace length) that inhabit nursery grounds (preferably among red algae) displayed a disruptive pattern (camouflage), whereas larger juveniles displayed a bicolour pigmentation typical of adult lobsters. This shift in colour pattern further suggests that small lobsters employ cryptic coloration throughout their asocial algal stage. However, this cryptic coloration offers no advantage when lobsters grow larger and start dwelling in crevices. Other structures linked to reproduction (e.g. female pleopods and male pereopods) experienced either isometric or positive allometric growth throughout ontogeny. Our results support one of the main predictions of resource allocation theory and demonstrate ontogenetic shifts in defensive structures and coloration concomitantly with changes in lobster mortality risk mediated by size-dependent predation risk. © 2012 The Linnean Society of Londo

    Innate immune modulation by GM-CSF and IL-3 in health and disease

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    Granulocyte-macrophage colony-stimulating factor (GM-CSF) and inteleukin-3 (IL-3) have long been known as mediators of emergency myelopoiesis, but recent evidence has highlighted their critical role in modulating innate immune effector functions in mice and humans. This new wealth of knowledge has uncovered novel aspects of the pathogenesis of a range of disorders, including infectious, neoplastic, autoimmune, allergic and cardiovascular diseases. Consequently, GM-CSF and IL-3 are now being investigated as therapeutic targets for some of these disorders, and some phase I/II clinical trials are already showing promising results. There is also pre-clinical and clinical evidence that GM-CSF can be an effective immunostimulatory agent when being combined with anti-cytotoxic T lymphocyte-associated protein 4 (anti-CTLA-4) in patients with metastatic melanoma as well as in novel cancer immunotherapy approaches. Finally, GM-CSF and to a lesser extent IL-3 play a critical role in experimental models of trained immunity by acting not only on bone marrow precursors but also directly on mature myeloid cells. Altogether, characterizing GM-CSF and IL-3 as central mediators of innate immune activation is poised to open new therapeutic avenues for several immune-mediated disorders and define their potential in the context of immunotherapies
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