383 research outputs found

    Girona, ciudad semilla de ciencia : educación científica para la sostenibilidad

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    Las ciudades ‘semilla de ciencia’ son el caballo de batalla del proyecto europeo Pollen, seed cities for science: a community approach for a sustainable growth of science education in Europe dirigido principalmente a las etapas de educación infantil y primaria. En la presente comunicación se analiza el proyecto ‘Girona, ciudad semilla de ciencia’ bajo el prisma de la educación para la sostenibilidad. Tomando como marco de referencia las características de la educación ambiental se analizan cualitativamente los diferentes componentes del proyecto. Como conclusión, se identifican debilidades y fortalezas del proyecto y se apuntan propuestas de mejoría para avanzar en la educación para la sostenibilidad, desde la educación científica y en el contexto de una ciudad semilla de ciencia. Finalmente, se proponen posibles nuevas líneas de investigación

    Automated Crowdturfing Attacks and Defenses in Online Review Systems

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    Malicious crowdsourcing forums are gaining traction as sources of spreading misinformation online, but are limited by the costs of hiring and managing human workers. In this paper, we identify a new class of attacks that leverage deep learning language models (Recurrent Neural Networks or RNNs) to automate the generation of fake online reviews for products and services. Not only are these attacks cheap and therefore more scalable, but they can control rate of content output to eliminate the signature burstiness that makes crowdsourced campaigns easy to detect. Using Yelp reviews as an example platform, we show how a two phased review generation and customization attack can produce reviews that are indistinguishable by state-of-the-art statistical detectors. We conduct a survey-based user study to show these reviews not only evade human detection, but also score high on "usefulness" metrics by users. Finally, we develop novel automated defenses against these attacks, by leveraging the lossy transformation introduced by the RNN training and generation cycle. We consider countermeasures against our mechanisms, show that they produce unattractive cost-benefit tradeoffs for attackers, and that they can be further curtailed by simple constraints imposed by online service providers

    Microevents produced by gas migration and expulsion at the seabed: A study based on sea bottom recordings from the Sea of Marmara

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    International audienceDifferent types of 4-component ocean bottom seismometers (OBS) were deployed for variable durations ranging from 1 week to about 4 months in 2007, over soft sediments covering the seafloor of the Tekirdag Basin (western part of the Sea of Marmara, Turkey). Non-seismic microevents were recorded by the geophones, but generally not by the hydrophones, except when the hydrophone is located less than a few tens of centimetres above the seafloor. The microevents are characterized by short durations of less than 0.8 s, by frequencies ranging between 4 and 30 Hz, and by highly variable amplitudes. In addition, no correlation between OBSs was observed, except for two OBSs, located 10 m apart. Interestingly, a swarm of ∼400 very similar microevents (based on principal component analysis) was recorded in less than one day by an OBS located in the close vicinity of an active, gas-prone fault cutting through the upper sedimentary layers. The presence of gas in superficial sediments, together with analogies with laboratory experiments, suggest that gas migration followed by the collapse of fluid-filled cavities or conduits could be the source of the observed microevents. This work shows that OBSs may provide valuable information to improve our understanding of natural degassing processes from the seafloor

    Overview of the design of the ITER heating neutral beam injectors

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    The heating neutral beam injectors (HNBs) of ITER are designed to deliver 16.7MWof 1 MeVD0 or 0.87 MeVH0 to the ITER plasma for up to 3600 s. They will be the most powerful neutral beam\uf0a0(NB) injectors ever, delivering higher energy NBs to the plasma in a tokamak for longer than any previous systems have done. The design of the HNBs is based on the acceleration and neutralisation of negative ions as the efficiency of conversion of accelerated positive ions is so low at the required energy that a realistic design is not possible, whereas the neutralisation ofH 12 andD 12 remains acceptable ( 4856%). The design of a long pulse negative ion based injector is inherently more complicated than that of short pulse positive ion based injectors because: \u2022 negative ions are harder to create so that they can be extracted and accelerated from the ion source; \u2022 electrons can be co-extracted from the ion source along with the negative ions, and their acceleration must be minimised to maintain an acceptable overall accelerator efficiency; \u2022 negative ions are easily lost by collisions with the background gas in the accelerator; \u2022 electrons created in the extractor and accelerator can impinge on the extraction and acceleration grids, leading to high power loads on the grids; \u2022 positive ions are created in the accelerator by ionisation of the background gas by the accelerated negative ions and the positive ions are back-accelerated into the ion source creating a massive power load to the ion source; \u2022 electrons that are co-accelerated with the negative ions can exit the accelerator and deposit power on various downstream beamline components. The design of the ITER HNBs is further complicated because ITER is a nuclear installation which will generate very large fluxes of neutrons and gamma rays. Consequently all the injector components have to survive in that harsh environment. Additionally the beamline components and theNBcell, where the beams are housed, will be activated and all maintenance will have to be performed remotely. This paper describes the design of theHNBinjectors, but not the associated power supplies, cooling system, cryogenic system etc, or the high voltage bushingwhich separates the vacuum of the beamline fromthehighpressureSF6 of the high voltage (1MV) transmission line, through which the power, gas and coolingwater are supplied to the beam source. Also themagnetic field reduction system is not described

    Gas and seismicity within the Istanbul seismic gap

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    Understanding micro-seismicity is a critical question for earthquake hazard assessment. Since the devastating earthquakes of Izmit and Duzce in 1999, the seismicity along the submerged section of North Anatolian Fault within the Sea of Marmara (comprising the “Istanbul seismic gap”) has been extensively studied in order to infer its mechanical behaviour (creeping vs locked). So far, the seismicity has been interpreted only in terms of being tectonic- driven, although the Main Marmara Fault (MMF) is known to strike across multiple hydrocarbon gas sources. Here, we show that a large number of the aftershocks that followed the M 5.1 earthquake of July, 25th 2011 in the western Sea of Marmara, occurred within a zone of gas overpressuring in the 1.5–5 km depth range, from where pressurized gas is expected to migrate along the MMF, up to the surface sediment layers. Hence, gas-related processes should also be considered for a complete interpretation of the micro- seismicity (~M < 3) within the Istanbul offshore domain

    Arnis-based Exercise Program for Balance Control in Community-Dwelling Older Adults: Study Protocol for a Pilot Randomized Controlled Trial

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    Background: Aging causes impairment in balance and increases the prevalence of falls in older adults. Martial arts are now incorporated into exercise programs to improve balance. Arnis, a Filipino Martial Art, can improve the balance control of older adults. Objectives: This study primarily aims to determine the effects of an Arnis-based exercise program on balance control of healthy community-dwelling older adults. This study also aims to describe its effect on older adults’ concerns about falling and lower limb functional strength. Methods:This will be a single-blind, pilot randomized controlled trial. Participants will be randomly allocated to either the intervention or control group. The intervention group will perform an Arnis-based exercise program for 40-60 minutes per session thrice a week for 12 weeks. The control group will continue to do their usual activities for the duration of the study. Participants will be measured at baseline and 12 weeks after for balance, concern for falling, and lower limb strength using the Berg Balance Scale, Timed-Up and Go Test, Falls Efficacy Scale-International Filipino, and the 30-second Chair Sit-to-stand Test, respectively. Data will be analysed through independent and paired t-tests. A p-value Expected Results: Significant improvements in the balance scores in the intervention group are expected after 12 weeks of the Arnis-based exercise program, along with its effects on concerns for falling and lower extremity strength. The pilot study will provide data on the effectiveness of Arnis as a reference for future larger experimental studies

    ZZW-115-dependent inhibition of NUPR1 nuclear translocation sensitizes cancer cells to genotoxic agents

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    Establishing the interactome of the cancer-associated stress protein Nuclear Protein 1 (NUPR1), we found that it binds to several hundreds of proteins, including proteins involved in nuclear translocation, DNA repair, and key factors of the SUMO pathway. We demonstrated that the NUPR1 inhibitor ZZW-115, an organic synthetic molecule, competes with importins for the binding to the NLS region of NUPR1, thereby inhibiting its nuclear translocation. We hypothesized, and then proved, that inhibition of NUPR1 by ZZW-115 sensitizes cancer cells to DNA damage induced by several genotoxic agents. Strikingly, we found that treatment with ZZW-115 reduced SUMOylation of several proteins involved in DNA damage response (DDR). We further report that the presence of recombinant NUPR1 improved the SUMOylation in a cell-free system, indicating that NUPR1 directly stimulates the SUMOylation machinery. We propose that ZZW-115 sensitizes cancer cells to genotoxic agents by inhibiting the nuclear translocation of NUPR1 and thereby decreasing the SUMOylation-dependent functions of key proteins involved in the DDR

    Measurement of the neutron flux at the Canfranc Underground Laboratory with HENSA

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    We have performed a long-term measurement of the neutron flux with the High Efficiency Neutron Spectrometry Array HENSA in the Hall A of the Canfranc Underground Laboratory. The Hall A measurement campaign lasted from October 2019 to March 2021, demonstrating an excellent stability of the HENSA setup. Preliminary results on the neutron flux from this campaign are presented for the first time. In Phase 1 (113 live days) a total neutron flux of 1.66(2) ×\times105^{-5} cm2^{-2} s1^{-1} is obtained. Our results are in good agreement with those from our previous shorter measurement where a reduced experimental setup was employed.Comment: Proceedings of the 17th International Conference on Topics in Astroparticle and Underground Physics (TAUP 2021
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