bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generating Transverse Loop Oscillations through a Steady-flow Driver
Authors: Karampelas Konstantinos , Van Doorsselaere Tom 
Published: July 2020

Abstract
In recent years, the decay-less regime of standing transverse oscillations in coronal loops has been the topic of many observational and numerical studies, focusing on their physical characteristics, as well as their importance for coronal seismology and wave heating. However, no definitive answer has yet been given on the driving mechanism behind these oscillations, with most studies focusing on the use of periodic footpoint drivers as a means to excite them. In this paper, our goal is to explore the concept of these standing waves being self-sustained oscillations, driven by a constant background flow. To that end, we use the PLUTO code, to perform 3D magnetohydrodynamic simulations of a gravitationally stratified straight flux tube in a coronal environment, in the presence of a weak flow around the loop, perpendicular to its axis. Once this flow is firmly set up, a transverse oscillation is initiated, dominated by the fundamental kink mode of a standing wave, while the existence of a second harmonic is revealed, with a frequency ratio to the fundamental mode near the observed ones in decay-less oscillations. The presence of vortex shedding is also established in our simulations, which is connected to the “slippery” interaction between the oscillator and its surrounding plasma. We thus present a proof-of-concept of a self-oscillation in a coronal loop, and we propose it as a mechanism that could interpret the observed decay-less transverse oscillations of coronal loops.
Hadronic versus Leptonic Models for γ-Ray Emission from VER J2227+608
Authors: Liu Siming , Zeng Houdun , Xin Yuliang , Zhu Hui 
Published: July 2020

Abstract
Recent observations of VER J2227+608 reveal a broken power γ-ray spectrum with the spectral index increasing from ∼1.8 in the GeV energy range to ∼2.3 in the TeV range. Such a spectral break can be attributed to radiative energy loss of energetic electrons in the leptonic scenario for the γ-ray emission, which, in combination with the characteristic age of the nearby pulsar, can be used to constrain the magnetic field in the emission region. We show that the radio and X-ray observations can also be explained in such a scenario. In the hadronic scenario, the spectral break can be attributed to diffusion of energetic ions in a turbulent medium and detailed spectral measurement can be used to constrain the diffusion coefficient. These two models, however, predict drastically different spectra above 100 TeV, which will be uncovered with future high-resolution observations, such as Large High Altitude Air Shower Observatory (LHAASO) and/or Cherenkov Telescope Array (CTA).
The Ionized Warped Disk and Disk Wind of the Massive Protostar Monoceros R2-IRS2 Seen with ALMA
Authors: Jiménez-Serra Izaskun , Báez-Rubio Alejandro , Martín-Pintado Jesús , Zhang Qizhou , Rivilla Víctor M. 
Published: July 2020

Abstract
Theories of massive star formation predict that massive protostars accrete gas through circumstellar disks. Although several cases have been found already thanks to high angular-resolution interferometry, the internal physical structure of these disks remains unknown, in particular whether they present warps or internal holes, as observed in low-mass protoplanetary disks. Here, we report very high angular-resolution observations of the H21α radio recombination line carried out in Band 9 with the Atacama Large Millimeter/submillimeter Array (beam of 80 mas × 60 mas, or 70 au × 50 au) toward the IRS2 massive young stellar object in the Monoceros R2 star-forming cluster. The H21α line shows maser amplification, which allows us to study the kinematics and physical structure of the ionized gas around the massive protostar down to spatial scales of ∼1–2 au. Our ALMA images and 3D radiative transfer modeling reveal that the ionized gas around IRS2 is distributed in a Keplerian circumstellar disk and an expanding wind. The H21α emission centroids at velocities between −10 and 20 km s−1 deviate from the disk plane, suggesting a warping for the disk. This could be explained by the presence of a secondary object (a stellar companion or a massive planet) within the system. The ionized wind seems to be launched from the disk surface at distances ∼11 au from the central star, consistent with magnetically-regulated disk wind models. This suggests a similar wind-launching mechanism to that recently found for evolved massive stars such as MWC349A and MWC922.
Disease Risk–Associated Genetic Variants in STAT1 and STAT4 Function in a Complementary Manner to Increase Pattern-Recognition Receptor–Induced Outcomes in Human Macrophages
Authors: Hedl Matija , Sun Rui , Abraham Clara 
Published: July 2020

Abstract
STAT proteins can regulate both pro- and anti-inflammatory cytokine signaling. Therefore, identifying consequences of modulating expression of a given STAT is ultimately critical for determining its potential as a therapeutic target and for defining the mechanisms through which immune-mediated disease variants in STAT genes contribute to disease pathogenesis. Genetic variants in the STAT1/STAT4 region are associated with multiple immune-mediated diseases, including inflammatory bowel disease (IBD). These diseases are characterized by dysregulated cytokine secretion in response to pattern-recognition receptor (PRR) stimulation. We found that the common IBD-associated rs1517352 C risk allele increased both STAT1 and STAT4 expression in human monocyte-derived macrophages (MDMs). We therefore hypothesized that the STAT1/STAT4 variant might regulate PRR-initiated responses in a complementary and cooperative manner because of the important role of autocrine/paracrine cytokines in modulating PRR-initiated signaling. STAT1 and STAT4 were required for PRR- and live bacterial-induced secretion of multiple cytokines. These outcomes were particularly dependent on PRR-initiated autocrine/paracrine IL-12–induced STAT4 activation to generate IFN-γ, with autocrine IFN-γ then signaling through STAT1. STAT1 and STAT4 also promoted bacterial-induced cytokines in intestinal myeloid cells and PRR-enhanced antimicrobial pathways in MDMs. Importantly, MDMs from rs1517352 C IBD risk allele carriers demonstrated increased TLR4-, IFN-γ– and IL-12–induced STAT1 and STAT4 phosphorylation and cytokine secretion and increased TLR4-enhanced antimicrobial pathways. Taken together, STAT1 and STAT4 expression is coregulated by a shared genetic region, and STAT1/STAT4-immune disease–associated variants modulate IFN-γ– and IL-12–associated outcomes, and in turn, PRR-induced outcomes, highlighting that these genes cooperate to regulate pathways relevant to disease pathogenesis.
Exotic t-structures and actions of quantum affine algebras
Authors: Cautis Sabin , Koppensteiner Clemens 
Published: July 2020

We explain how quantum affine algebra actions can be used to systematically construct "exotic" t-structures. The main idea, roughly speaking, is to take advantage of the two different descriptions of quantum affine algebras, the Drinfeld–Jimbo and the Kac–Moody realizations.
Our main application is to obtain exotic t-structures on certain convolution varieties defined using the Beilinson–Drinfeld and affine Grassmannians. These varieties play an important role in the geometric Langlands program, knot homology constructions, K-theoretic geometric Satake and the coherent Satake category. As a special case we also recover the exotic t-structures of Bezrukavnikov–Mirković [BM] on the (Grothendieck–)Springer resolution in type A.
Effect of Graded Oil Palm Kernel Shells on Compaction of Weak o Problematic Sub-Grade Soils
Authors: Affam M. , Wilson R. Ewusi , Asenso-Gjambibi D. 
Published: July 2020

AbstractSub-grade is the ultimate load bearer of vehicular traffic load in a pavement structure. A weak sub-grade or problematic soils require some improvements like soil stabilisation, soil reinforcement and/or capping of the sub-grade layer. These sub-grade improvement methods increase the total project cost because non-local materials such as cement, geosynthetics and hydrated lime are commonly used. The use of graded oil palm kernel shells (OPKS) which are local, cheaper and readily available as a soil improvement material was assessed in this research. This assessment was done by mixing sub-grade material with 2.8 mm, 5 mm and 10 mm graded OPKS. 10 %, 20 % and 30 % of each graded OPKS was added separately to the soil to form nine composite materials. These composite materials including the natural soil were tested for their California Bearing Ratio (CBR) values. The investigation proved that the composite made of 20 % 2.8 mm graded OPKS yielded a soaked CBR of 23.5 % which is a 197.47 % increase in soaked CBR compared to that of the natural soil. The soaked CBR samples of the graded OPKS composite materials absorbed lesser amounts of water in comparison to that of the natural soil. This behaviour implies that some capillary force created at un-soaked condition in the composite materials was preserved; therefore, the composite materials generally have higher CBR values than the natural soil. Keywords: Oil Palm Kernel Shells (OPKS), Problematic Soils, Lightweight Aggregate (LWA)
The Trajectory of Lost Mercury in Artisanal and Small Scale Gold Extraction in Ghana
Authors: Al-Hassan S , Yaganuma L. , Odoi B. 
Published: July 2020

AbstractThe Artisanal and Small Scale Mining (ASSM) industry is of great importance to the Ghanaian economy. It provides employment for the teeming youth directly and indirectly and produces gold for the local goldsmiths, among other benefits. Concomitant to their operations, ASSM causes significant environmental pollution with chemicals, predominantly mercury. Mercury is used by small scale miners in the processing of ore mined because it is relatively easy to use and readily available. The laws regulating small scale gold mining in Ghana do not forbid the use of mercury even though there is a loud outcry against the use of mercury in small scale gold mining. The operations have resulted in the discharge of mercury into the environment indiscriminately. No attempt is made by the miners to recover lost mercury hence all of it is lost to the environment. This paper presents the findings of a study that investigated the trajectory of the mercury lost into the environment. The results showed that 2 g of mercury was lost to the environment for every gram of gold recovered through ASSM; 39% of it was lost to the atmosphere due to roasting of the amalgam whilst the remaining 61% was lost into water and spillage onto the ground. Keywords: Mercury, Atmosphere, Pollution, Environment, Socio-economic
Vacuum Pyrolysis of Waste Vehicle Tyres into Oil Fuel Using A Locally, Fabricated Reactor
Authors: Quaicoe I. , Souleymane A. A. , Kyeremeh S. K. , Appiah-Twum H. , Ndur S. A. 
Published: July 2020

Abstract
Some countries still face daunting challenges of managing ever-increasing waste generated, especially plastic and waste vehicle tyres. Whilst some developed countries have adopted innovative ways such as catalytic or pyrolytic decomposition processes for energy or fuel generation from these wastes, developing countries like Ghana still dispose off indiscriminately around communities or un-engineered dumpsites. Hence, this study sought to transform waste vehicle tyres into fuel which invariably minimises or eliminates its environmental impact. Particularly, waste vehicle tyres (sourced from dumpsites in Tarkwa, Ghana) were washed, shredded and decomposed via pyrolysis at high temperature range (~ 450 - 650 oC) using locally designed and fabricated reactor. The physicochemical properties (such as water content, flashpoint, density, sulphur content, solids and viscosity) of the pyrolysis oil produced were also examined using the American Society for Testing and Materials (ASTM) standards and procedures. The results showed that the viscosity, flashpoint and the density of the pyrolysis oil produced were 0.904 cSt, 34.5 oC, and 850.6 kg/m3 (at 15 oC), respectively. The sulphur, water and solids/particulates contents were 4340.0 ppm, 0.8 vol.%, and 483,495.5 ppm, respectively. It was also observed that the pyrolysis oil obtained appeared as thick, single-phase liquid with dark colour and strong odour at room temperature. Relatively, the properties of pyrolysis oil produced without further treatment did not meet the International specification for diesel fuel, hence its usage would require further treatments such as desulphurisation, decanting, centrifugation and filtration. Overall, the study has demonstrated that the pyrolysis of waste vehicle tyres into fuel provides an alternative method for managing end-of-life vehicle tyres and adding value to waste in general.

Keywords: Pyrolysis, Waste Vehicle Tyres, Reactor, Pyrolysis Oil, Biofuel
Spatial Analysis of Artisanal and Small-Scale Mining in the Tarkwa-Nsuaem Municipality of Ghana
Authors: Kumi-Boateng B. , Stemn E. 
Published: July 2020

Abstract
In recent times there have been lots of public outcry on the environmental and public health and safety effects of Artisanal and Small-scale gold Mining (ASM) and the need to monitor ASM activities for reclamation purposes. To effectively develop and deploy policy responses to the environmental and human health effects of ASM, knowledge of the locations and distribution of ASM sites is a prerequisite. However, information regarding ASM hotspots and spatial distribution, the scope and types of ASM operations are hard to find. Therefore, this research was designed to use satellite-based data to map out ASM sites, focusing on the Tarkwa-Nsuaem municipality as the study area. Several image processing techniques were applied on a Landsat 8 satellite image downloaded from the US Geological Survey website. The image processing resulted in the identification of 221 clusters of ASM sites, representing 12.72% of the total size of the study area. To further explore the effects of these ASM sites, Areas of Interest (AOI) including forest reserve, rivers, large-scale mines and urban settlements were defined. By selecting and analysing the location and distribution of the ASM sites in relations to the AOI, the study was effective in identifying environmentally sensitive and critical areas warranting the urgent attention of society to mitigate the health, safety and ecosystem service effects of ASM in the study area. By identifying the environmental sensitive areas being affected by ASM, the findings could support the prioritisation of reclamation efforts.

Keywords: Artisanal Small-Scale Mining, Satellite Image, Environmental Effect, Public Health and Safety
Analysis of Effects of Selected Aerosol Particles to the Global Climate Change and Health using Remote Sensing data: The Focus on Africa
Authors: Rushingabigwi G , Kalisa W , Nsengiyumva P , Zimulinda F , Mukanyiligira D , Sibomana L 
Published: July 2020

The desert's dust and anthropogenic biomass burning's black carbon (BC) in the tropical regions are associated with many effects on climate and air quality. The dust and BC are the selected aerosols, which affect health by polluting the breathable air. This research discusses the effects of both the aerosols, especially while they interact with the clouds. The respective aerosol extinction optical thickness (AOT) extinction was analysed with the sensible heat from Turbulence. The research purposes to quantitatively study the remote sensing data for fine particulate matter, PM2.5, heterogeneously mixing both the dust and the pulverized black carbon's soot or ash, to analyse at which levels PM2.5 can endanger human health in the sub-Saharan region. The mainly analysed data had been assimilated from different remote sensing tools; the Goddard interactive online visualization and analysis infrastructure (GIOVANNI) was in the centre of data collection; GIS, the research data analysis software. In results, the rise and fall of the averaged sensible heat were associated with the rise and fall of averaged aerosol extinction AOT; the direct effects of the selected aerosols on the clouds are also presented. Regarding the health effects, PM2.5 quantities are throughout beyond the tolerably recommended quantity of 25μg/m3; thus, having referred to erstwhile research, inhabitants would consume food and drug supplements which contain vanillic acid during dusty seasons.
Keywords: Geographic Information System (GIS), remotely sensed data, spatio-temporal (data) analysis
Integrating Local Community Perception and Expert’s Knowledge in Spatial Multi-Criteria Evaluation (SMCE) for Landfill Siting in Musanze Secondary City
Authors: Ngwijabagabo H , Nyandwi E , Barifashe T 
Published: July 2020

Illegal dumping and landfilling of solid waste is a thoughtful concern nowadays. Solid wastes are disposed in open dumping sites and there is a lack of effective selection of potential and suitable site (s) for landfill, due to the ignorance of all criteria to be integrated in process of decision making. The purpose of this research is to find the most suitable site(s) for the construction of modern landfills using spatial multi-criteria evaluation (SMCE) and addressing the existing gap in involving the local community in the process of siting. Seven criteria of siting were selected combining national and international guidelines for landfill siting criteria. Selected criteria thresholding and ranking decision were grounded on local community preferences. Suitable criteria proximity distances were assessed with a questionnaire survey and further weighted using Expert’s knowledge depending upon their relative importance. Final spatial overlay analysis results showed that the majority of the total area (98.31%) is classified as unsuitable, with 0.05% of the total area being less suitable, 1.21% moderately suitable and only 0.43% of the total area is most suitable. Only 2 sites were found to be qualified as the most suitable and have the capacity of serving at least 10 years. This study is a model for filling the gap of community consultation during the process of landfill siting. It is also a very supportive tool for decision-makers to reduce “Not in my backyard” (NIMBY) phenomenon of waste disposal as well as environmental problems associated with illegal dumping.
Keywords: Landfill Siting, Expert’s knowledge, Local community preferences, Spatial Multi-Criteria Evaluation.
PERAN HUMAS PEMERINTAH KOTA DENPASAR DALAM MENUNJANG PELAYANAN PUBLIK DI KOTA DENPASAR
Authors: Kotaniartha I wayan , Triske julianty putra Ni nyoman 
Published: July 2020

Humas adalah Usaha untuk menciptakan hubungan yang harmonis antara satu badan atau organisasi dengan masyarakat melalui suatu proses komunikasi timbal balik atau dua arah. Dalam penelitian yang berjudul “Peran Humas Pemerintah Kota Denpasar Dalam Menunjang Pelayanan Publik di Kota Denpasar” ini bertujuan untuk mengetahui peran humas Pemerintah Kota Denpasar dalam menunjang pelayanan publik di Kota Denpasar dan hambatan-hambatan Humas Pemerintah Kota Denpasar dalam menunjang pelayanan publik di Kota Denpasar. Data dikumpulkan dengan teknik wawancara dan dokumentasi. Untuk memecahkan masalah digunakan teknik analisis kualitatif. Bagian Humas dan Protokol tersebut memiliki peran dalam penyebarluasan Informasi pelaksanaan Pemerintahan dan Pembangunan Kota Denpasar dan Mempublikasikan program-program pelayanan publik. Hambatan-hambatan yang ditemukan terkait dengan tugas pokok dan fungsi Bagian Humas dan Protokol Setda Kota Denpasar dalam upaya menunjang pelayanan publik adalah : Adanya perubahan paradigma pers menuju industri pers sehingga belum semua media dapat mempublikasikan informasi yang disediakan melalui press release/website, Keterbatasan Sumber Daya Manusia baik kuantitas maupun kualitas pada Bagian Humas dan Protokol sehingga belum mampu menjadi Humas dan Protokol sesuai amanat peraturan perundang-undangan, Intensitas tugas yang sulit diprediksi sehingga seringkali mengakibatkan lemahnya perencanaan dan juga pelaksanaannya
Contrasting decadal trends of subsurface excess nitrate in the western and eastern North Atlantic Ocean
Authors: Yang Jin-Yu Terence , Lee Kitack , Zhang Jia-Zhong , Moon Ji-Young , Lee Joon-Soo , Han In-Seong , Lee Eunil 
Published: July 2020

Abstract. Temporal variations in excess nitrate (DINxs) relative to dissolved
inorganic phosphorus (DIP) were evaluated using datasets derived from
repeated measurements along meridional and zonal transects in the upper
(200–600 m) North Atlantic (NAtl) between the 1980s and 2010s. The analysis
revealed that the DINxs trend in the western NAtl differed from that in
the eastern NAtl. In the western NAtl, which has been subject to atmospheric
nitrogen deposition (AND) from the USA, the subsurface DINxs
concentrations have increased over the last 2 decades. This increase was
associated with the increase in AND measured along the US East Coast, with a
mean lag period of 15 years. This time lag was approximately equivalent to
the time elapsed since the subsurface waters in the western NAtl were last
in contact with the atmosphere (the ventilation age), suggesting a major
role for a physical mechanism in transporting the AND signals to the
subsurface. Our finding provides evidence that the DINxs dynamics in
the western NAtl in recent years has been affected by anthropogenic nitrogen
inputs, although this influence is weak relative to that in the western North
Pacific. In contrast, a decreasing trend in subsurface DINxs was
observed after the 2000s in the eastern NAtl, particularly in the high
latitudes. This finding was not associated with the comparable decrease in
AND from Europe. Other natural processes (a possible decline in tropical
N2 fixation and weakening of the Atlantic meridional overturning
circulation) may be responsible, but lack of time-resolved data on
N2 fixation and meridional circulation is an impediment to assessment
of these processes. Our results highlight the importance of both
anthropogenic and natural forcing in impacting the nutrient dynamics in the
upper NAtl.
Conhecimento sobre doença pulmonar obstrutiva crônica em pacientes de diferentes níveis de atividade física
Authors: Souza Hortência Vilione Pereira de , Garcia Rejanny Duque Thomaz , Rabahi Marcelo Fouad , Corrêa Krislainy de Sousa 
Published: July 2020

O objetivo deste estudo foi identificar e comparar o nível de conhecimento sobre a doença pulmonar obstrutiva crônica em indivíduos ativos, sedentários e severamente inativos. Trata-se de um estudo transversal com indivíduos com doença pulmonar obstrutiva crônica. Para a coleta de dados, foi utilizada uma ficha de avaliação clínica, o Bristol COPD Knowledge Questionnaire e pedômetros (contador de passos). Foram avaliados 75 indivíduos, 70,7% são severamente inativos. Verificou-se um baixo nível de conhecimento sobre a doença pulmonar obstrutiva crônica (48,51 ± 9,08%), e constatou que indivíduos ativos, sedentários e severamente inativos apresentam o nível de conhecimento sobre a doença semelhante (50,19 ± 11,18% vs 46,48 ± 8,16% vs 48,79 ± 9,06 %, p=0,68). Conclui-se, portanto, que indivíduos com doença pulmonar obstrutiva crônica ativos, sedentários e severamente inativos apresentam conhecimento semelhante e reduzido sobre a doença.
Descritores: Doença Pulmonar Obstrutiva Crônica; Exercício Físico; Conhecimento.