503 research outputs found

    Molecular clouds and stellar feedback: an investigation of synthetic line and continuum emission maps

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    Molecular clouds are complex systems and the search of adequate observational measurements to trace their evolution is still an open problem. In this thesis, we use produce synthetic emission maps of the 12CO 1-0, 13CO 1-0, [CI] 1-0, and [CII] lines, as well as of the FIR continuum emission, to test to which extent these emission measurements can be used as tracers of the evolutionary stage of molecular clouds. We use numerical simulations of molecular clouds performed within the SILCC-Zoom project. These simulations include detailed stellar feedback due to ionizing radiation, external magnetic fields, and a chemical network evolved on-the-fly. We compare two different chemical networks, NL97 and NL99, and we find that NL97, even though it does not include neutral carbon, more accurately reproduces the abundances of CO and C+. We then use NL97 in the rest of the work. We introduce a novel post-processing procedure for the C+ abundance using CLOUDY, essential in HII regions to account for the higher ionization states due to stellar radiation. Furthermore, we show that assuming chemical equilibrium results in H and H2 being underestimated and overestimated, respectively, by up to a factor of 2. The abundances of C+ and CO are also, respectively, underestimated and overestimated. This is reflected and amplified in the estimation of the CO and [CII] luminosity as well. We also investigate the capability of the L_CO/L_[CII] luminosity ratio to trace the H2 mass fraction in the clouds, but find no clear trend. We then investigate the [CII]/FIR ratio in HII regions and in entire clouds with stellar feedback. In young HII regions the drop of the [CII]/FIR intensity ratio is mainly due to the strong FIR emission produced by hot and dense dust, and the contemporary saturation of the [CII] line. In more evolved HII regions, the second ionization of carbon is the main reason for the low [CII]/FIR ratio. The evolution of this ratio is reflected in the evolution of the L_[CII]/L_FIR luminosity ratio in the entire clouds. This evolution can be schematized in three phases. Overall, L_[CII]/L_FIR is well correlated with the total stellar luminosity L_*tot. The relation between L_[CII]/L_FIR andL_*tot can be fitted with a power-law. When L_*tot is large, i.e., in evolved clouds which formed many massive stars, L_[CII]/L_FIR is particularly low, determining an observable [CII]-deficit in these clouds. However, this relation breaks when the total FIR luminosity stars decreasing as a consequence of the cloud dispersal caused by the stellar feedback. The aspect of HII regions in molecular clouds strongly depends on the geometry of the cloud, and on the line of sight. Indeed, a certain HII region can have different properties when observed from different LOS, and apparent HII regions, which are actually only the result of projection effects, can be observed

    International Academic Symposium of Social Science 2022

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    This conference proceedings gathers work and research presented at the International Academic Symposium of Social Science 2022 (IASSC2022) held on July 3, 2022, in Kota Bharu, Kelantan, Malaysia. The conference was jointly organized by the Faculty of Information Management of Universiti Teknologi MARA Kelantan Branch, Malaysia; University of Malaya, Malaysia; Universitas Pembangunan Nasional Veteran Jakarta, Indonesia; Universitas Ngudi Waluyo, Indonesia; Camarines Sur Polytechnic Colleges, Philippines; and UCSI University, Malaysia. Featuring experienced keynote speakers from Malaysia, Australia, and England, this proceeding provides an opportunity for researchers, postgraduate students, and industry practitioners to gain knowledge and understanding of advanced topics concerning digital transformations in the perspective of the social sciences and information systems, focusing on issues, challenges, impacts, and theoretical foundations. This conference proceedings will assist in shaping the future of the academy and industry by compiling state-of-the-art works and future trends in the digital transformation of the social sciences and the field of information systems. It is also considered an interactive platform that enables academicians, practitioners and students from various institutions and industries to collaborate

    The Role of Professional Identity into Explaining Saudi Arabian Healthcare Professional Resistance to Electronic Health Records’ Stratigic Change in Public Hospitals

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    Electronic Health Record (EHR) is an application that captures patients’ information and promises to improve healthcare services. Hence, many countries, including the developing country, such as Saudi Arabia, invested heavily to implement the system and improve healthcare service delivery. Yet, the system's adoption is slow, and failure is high, which could be related to healthcare professionals’ resistance to change to the EHR applications. Further, despite the importance of the topic of EHR resistance, little research has been conducted in Saudi Arabia regarding healthcare professionals’ resistance to change to EHR. Motivated thus, this research suggested that resistance to EHR in Saudi Arabia results from cultural and professional identity factors, which guide healthcare professionals’ behaviour. Therefore, this research investigated how the professional identity of Saudi healthcare professionals can explain their resistance tousing EHR applications. The study used identity theory as our main theoretical lens along with Hofstede cultural dimension theory and in-depth qualitative interviews to understand the EHR resistance to change phenomenon. Our study has revealed similarities between Saudi and Western healthcare professionals’ factors that could contribute to EHR resistance. However, interestingly, cultural, and religious norms were also found to be one of the leading causes of Saudi healthcare professionals’ resistance to the EHR change. Our theoretical contributions helped us understand the role of identity in EHR use in a place where professionals with a strong professional and cultural identity are the system's main users. In addition, our practical contributions aimed to help the Ministry of Health in Saudi Arabia to understand what healthcare professional needs before adapting an EHR system, or improve the current once. Further, it could help hospital managers address, understand, and solve the challenges facing healthcare professionals as they use the EHR system

    Jupiter science Enabled by ESA's Jupiter Icy Moons Explorer

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    ESA's Jupiter Icy Moons Explorer (JUICE) will provide a detailed investigation of the Jovian system in the 2030s, combining a suite of state-of-the-art instruments with an orbital tour tailored to maximise observing opportunities. We review the Jupiter science enabled by the JUICE mission, building on the legacy of discoveries from the Galileo, Cassini, and Juno missions, alongside ground- and space-based observatories. We focus on remote sensing of the climate, meteorology, and chemistry of the atmosphere and auroras from the cloud-forming weather layer, through the upper troposphere, into the stratosphere and ionosphere. The Jupiter orbital tour provides a wealth of opportunities for atmospheric and auroral science: global perspectives with its near-equatorial and inclined phases, sampling all phase angles from dayside to nightside, and investigating phenomena evolving on timescales from minutes to months. The remote sensing payload spans far-UV spectroscopy (50-210 nm), visible imaging (340-1080 nm), visible/near-infrared spectroscopy (0.49-5.56 μm), and sub-millimetre sounding (near 530-625 GHz and 1067-1275 GHz). This is coupled to radio, stellar, and solar occultation opportunities to explore the atmosphere at high vertical resolution; and radio and plasma wave measurements of electric discharges in the Jovian atmosphere and auroras. Cross-disciplinary scientific investigations enable JUICE to explore coupling processes in giant planet atmospheres, to show how the atmosphere is connected to (i) the deep circulation and composition of the hydrogen-dominated interior; and (ii) to the currents and charged particle environments of the external magnetosphere. JUICE will provide a comprehensive characterisation of the atmosphere and auroras of this archetypal giant planet

    PRIMA General Observer Science Book

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    PRIMA (The PRobe for-Infrared Mission for Astrophysics) is a concept for a far-infrared (IR) observatory. PRIMA features a cryogenically cooled 1.8 m diameter telescope and is designed to carry two science instruments enabling ultra-high sensitivity imaging and spectroscopic studies in the 24 to 235 microns wavelength range. The resulting observatory is a powerful survey and discovery machine, with mapping speeds better by 2 - 4 orders of magnitude with respect to its far-IR predecessors. The bulk of the observing time on PRIMA should be made available to the community through a General Observer (GO) program offering 75% of the mission time over 5 years. In March 2023, the international astronomy community was encouraged to prepare authored contributions articulating scientific cases that are enabled by the telescope massive sensitivity advance and broad spectral coverage, and that could be performed within the context of GO program. This document, the PRIMA General Observer Science Book, is the edited collection of the 76 received contributions.Comment: A. Moullet, T. Kataria, D. Lis, S. Unwin, Y. Hasegawa, E. Mills, C. Battersby, A. Roc, M. Meixner are the editors of the PRIMA General Observer Science Book. The book compiles 76 authored contributions. 399 page

    50 Years of quantum chromodynamics – Introduction and Review

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    Jupiter Science Enabled by ESA's Jupiter Icy Moons Explorer

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    ESA’s Jupiter Icy Moons Explorer (JUICE) will provide a detailed investigation of the Jovian system in the 2030s, combining a suite of state-of-the-art instruments with an orbital tour tailored to maximise observing opportunities. We review the Jupiter science enabled by the JUICE mission, building on the legacy of discoveries from the Galileo, Cassini, and Juno missions, alongside ground- and space-based observatories. We focus on remote sensing of the climate, meteorology, and chemistry of the atmosphere and auroras from the cloud-forming weather layer, through the upper troposphere, into the stratosphere and ionosphere. The Jupiter orbital tour provides a wealth of opportunities for atmospheric and auroral science: global perspectives with its near-equatorial and inclined phases, sampling all phase angles from dayside to nightside, and investigating phenomena evolving on timescales from minutes to months. The remote sensing payload spans far-UV spectroscopy (50-210 nm), visible imaging (340-1080 nm), visible/near-infrared spectroscopy (0.49-5.56 μm), and sub-millimetre sounding (near 530-625 GHz and 1067-1275 GHz). This is coupled to radio, stellar, and solar occultation opportunities to explore the atmosphere at high vertical resolution; and radio and plasma wave measurements of electric discharges in the Jovian atmosphere and auroras. Cross-disciplinary scientific investigations enable JUICE to explore coupling processes in giant planet atmospheres, to show how the atmosphere is connected to (i) the deep circulation and composition of the hydrogen-dominated interior; and (ii) to the currents and charged particle environments of the external magnetosphere. JUICE will provide a comprehensive characterisation of the atmosphere and auroras of this archetypal giant planet

    The Relativization of Ethnicity and Circumcision in Paul and His Communities

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