Journal of Next-Generation Research 5.0
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Dynamics of cluster-forming hub-filament systems: The case of the high-mass star-forming complex Monoceros R2
No full textInternational audienceContext. High-mass stars and star clusters commonly form within hub-filament systems. Monoceros R2 (hereafter Mon R2), at a distance of 830 pc, harbors one of the closest of these systems, making it an excellent target for case studies.Aims. We investigate the morphology, stability and dynamical properties of the Mon R2 hub-filament system.Methods. We employed observations of the 13CO and C18O 1 →0 and 2 →1 lines obtained with the IRAM-30 m telescope. We also used H2 column density maps derived from Herschel dust emission observations.Results. We identified the filamentary network in Mon R2 with the DisPerSE algorithm and characterized the individual filaments as either main (converging into the hub) or secondary (converging to a main filament). The main filaments have line masses of 30–100 M⊙ pc−1 and show signs of fragmentation, while the secondary filaments have line masses of 12–60 M⊙ pc−1 and show fragmentation only sporadically. In the context of Ostriker’s hydrostatic filament model, the main filaments are thermally supercritical. If non-thermal motions are included, most of them are transcritical. Most of the secondary filaments are roughly transcritical regardless of whether non-thermal motions are included or not. From the morphology and kinematics of the main filaments, we estimate a mass accretion rate of 10−4–10−3 M⊙ yr−1 into the central hub. The secondary filaments accrete into the main filaments at a rate of 0.1–0.4 × 10−4 M⊙ yr−1. The main filaments extend into the central hub. Their velocity gradients increase toward the hub, suggesting acceleration of the gas. We estimate that with the observed infall velocity, the mass-doubling time of the hub is ~2.5 Myr, ten times longer than the free-fall time, suggesting a dynamically old region. These timescales are comparable with the chemical age of the HII region. Inside the hub, the main filaments show a ring- or a spiral-like morphology that exhibits rotation and infall motions. One possible explanation for the morphology is that gas is falling into the central cluster following a spiral-like pattern
Rate Adaptive Congestion Control Using Lookup Table Scheme to Enhance Quality of Experience
No full textPart 4: Local Technical PapersInternational audienceIn recent years video communication has occupied a large percentage of Internet traffic and the trend is expected to increase. Many services are offered via the Internet use video content to reach millions of users. Real time video services in the Internet are mostly done by using User Datagram Protocol (UDP). UDP is preferable because it is fast, but has a weakness of not supporting congestion control mechanisms; hence it usually floods the channel it is using causing congestion which then leads to packet loss, excessive delay and jitter. To support good quality of experience (QoE), packet loss, delay and jitter must be kept at accepted values.This paper presents part of an ongoing MSc. research work whose aim is to develop a rate adaptive congestion control scheme using a lookup table. The scheme use Real Time Transport Protocol (RTP) and RTP Control Protocol (RTCP) to provide end to end network transport service which is not provided by UDP and control service. The proposed congestion control scheme comprises of two components:- a lookup table and congestion control equation. The lookup table is created at the beginning of sender’s application and keeps a record of fraction loss and Inter Packet Gap (IPG), which is the interval in time between sending packets. Upon receiving a report the lookup table is searched to see if there is a match for the report’s fraction loss value and returns, the appropriate IPG value. If there is no match a congestion control equation is used to compute a new IPG value, which is then added to the lookup table and used for rate adjustment.Simulation of the proposed work was done using NS3, where by the Quality of Service (Qos) parameter which affect the Quality of Experience (QoE) such as delay and jitter were observed. Elvavid, a video quality evaluation tool is used to measure the quality of video by using Peak Signal Noise Ratio (PSNR) and Mean Opinion Score (MOS) measurements
Relationship between Secondary Metabolites, Antiradical Activities, and Colour Characteristics of Cochlospermum Tinctorium A. Rich. (Bixaceae) Root
No full textInternational audienceCochlospermum tinctorium A. Rich. (Bixaceae) is a widespread herbaceous plant in the African sahelian and soudanian zones. Its root is used as food and medicinal plant. Studies of secondary metabolites, functional activities and trichromatic parameters were realized according to standard methods of laboratory. At a threshold of α = 0.05, significant correlations (p < 0.05) were found between secondary metabolites contents and functional activities such as radical scavenging activity of antioxidant component or hydroxyl radical scavenging activity. The value of DPPHH was 95.56 ± 0.94% for CT inner Matrix with variation of 0.12% for CT Soaked inner Matrix and 1.63% for CT Peeler. But HSRA was 37.14 ± 5.71 for CT inner Matrix with variation of -38.46% for CT Soaked inner Matrix and -71.79% for CT Peeler. Cochlospermum tinctorium root has exhibited efficiency to heal many diseases thanks to multiple bioactive compounds. In addition, the colour of powders depended upon chemical compounds. Finally, Cochlospermum tinctorium root was found to neutralize organic radicals and reactive oxygen species
Economic Theory, Phoenician Pre-coinage External Trade, Changes in the Economic Surplus and its Appropriation - An initial Perspective
No full textLes internes de médecine générale se sentent-ils libres de leurs rencontres avec l’industrie pharmaceutique ? Étude qualitative menée auprès d’internes en médecine générale de l’océan indien
No full textIntroduction : The pharmaceutical industry is omnipresent during the medical training program of doctors and it influences medical prescriptions. The objective of this work is to understand if general medical students feel free or influenced during their meetings with the pharmaceutical industry. Method : A qualitative study led with general medicine students located in the Indian Ocean, by means of semi-directed conversations and a group interview. Their analysis was made according to the grounded theory method of qualitative analysis using the SONAL software. Results : 13 medical students participated in the study. With regards to the main question posed in the study, the interns often felt that the meetings were pressured upon them, or by themselves. These encounters took place mainly at the hospital, during staffs meetings but also during outpatient training via medical visitors. They felt that their training in independence was insufficient to allow them to have more freedom. Discussion : Medical student do not always feel free to meet with the pharmaceutical industry, mainly due to hierarchical pressure and lack of training. To remedy this would require the elaboration of a charter on independence with regards to the pharmaceutical industry destined for the university master course of La Réunion/ Mayotte and a training of students according to the Pharfree curriculum model of AMSA with an evaluation of these measures on the feeling of the medical students and the economic medical consequences of their actions.Introduction : L’industrie pharmaceutique est omniprésente dans le cursus de médecine. Elle influence les prescriptions médicales. L’objectif de ce travail est de savoir si les internes de médecine générale se sentent libres des rencontres avec l’industrie pharmaceutique. Méthode : Étude qualitative menée auprès d’internes de médecine générale de l’Océan Indien, par entretiens semi dirigés individuels et un entretien de groupe. L’analyse a été faite selon le modèle de la théorie ancrée à l’aide du logiciel SONAL. Résultats : 13 internes ont participé à l’étude. Sur la question principale de l’étude, les internes avaient le sentiment de rencontres souvent contraintes du fait de leurs chefs, de leurs services, ou d’eux mêmes. Ces rencontres se font principalement à l’hôpital, lors de staffs mais également en stage ambulatoire via les visiteurs médicaux. Ils estiment leur formation à l’indépendance insuffisante pour leur permettre d’avoir plus de liberté. Discussion : Les internes ne sentent pas toujours libre de leur rencontre avec l’industrie pharmaceutique, par pression hiérarchique principalement et manque de formation. Pour remédier à cela il faudrait une charte sur l’indépendance vis-à-vis de l’industrie pharmaceutique destinés aux maîtres de stages universitaires de la Réunion/Mayotte et une formation des étudiants selon le modèle Pharmfree curriculum de l’AMSA avec évaluation de ces mesures sur le ressenti des internes et les conséquences médicaux économique de ces actions
Optimization of absorption systems: case of the refrigerators and heat pumps
No full textInternational audienceThe new thermo-ecological performance optimization of absorption is investigated by taking the ecological coefficient of performance ECOP as an objective function. ECOP has been expressed in terms of the temperatures of the working fluid in the main components of the system. The maximum of ECOP and the corresponding optimal temperatures of the working fluid and other optimal performance design parameters such as coefficient of performance, specific cooling load of absorption refrigerators, specific heating load of absorption heat pumps, specific entropy generation rate and the distributions of the heat exchanger areas have been derived analytically. The obtained results may provide a general theoretical tool for the ecological design of absorption refrigerators and heat pumps
From CRITEX to OZCAR: Geophysical wandering accross the FrenchCritical Zone Observatorie
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Exploring the effects of national and regional popular vote Interstate compact on a toy symmetric version of the Electoral College: an electoral engineering perspective
No full textThe main purpose of this paper is to explore the consequences of the formation of either a Regional Popular Vote Interstate compact or a National Popular Vote Interstate compact on the functioning of a toy symmetric version of the Electoral College. The two versions of interstate compacts that are considered here differ in only one respect: in one case, the interstate compact allocates its electoral votes to the regional popular winner, while in the other case it allocates the votes to the national popular winner. They both differ from the ongoing National Popular Vote Interstate Compact as it is assumed that the agreement is effective as soon as the members sign it. Decisiveness and welfare analyses are conducted with a simplified symmetric theoretical version of the Electoral College wherein malapportionment problems are absent. The three most popular probabilistic models are considered and the study is conducted either from the self-interest perspective of the initiators of the interstate compact or from a general interest perspective. The analysis combines analytical arguments and simulations
Development of a physicochemical method to quantify the extracellular liquid volume: Application to the transformation of cassava into gari
No full textInternational audienceIn fresh vegetal materials, liquid is mostly located in cells. During processing, this liquid is distributed in the entire vegetal matrix volume including exctracellular volume. According to its location, it will be more or less available for physico-chemical mechanisms that takes place during processing of vegetal matrices. This availability greatly influences the quality of the final products. This work consisted in developing a method for determining the quantity of extracellular liquid in a cell-component food matrix. The method developed is spectrophotometric-based and consists in adding a known mass of polymer (poly(4-styrenesulfonate) sodium salt, PSS) to a rasped vegetal material and defining its concentration in the supernatant separated from the solid phase. The PSS molar mass prevents it from penetrating into plant cells. The PSS concentration measured makes it possible to calculate the extracellular liquid volume. The method validation and its application to rasped and processed (fermentation, pressing) cassava makes it possible to obtain results in agreement with those obtained with other methods