Top PDF Centrifugal acceleration in the magnetotail lobes

Centrifugal acceleration in the magnetotail lobes

Centrifugal acceleration in the magnetotail lobes

Several populations of different species and different en- ergy are thus of interest to understand both planetary atmo- spheric loss due to solar wind interaction and magnetospheric dynamics. One particularly difficult population to measure is the cold proton plasma in the lobes. These protons may have a significant flux while still not enough energy to be observ- able by particle spectrometers, due to the significant positive potential of a sunlit spacecraft in a tenuous plasma. This observational difficulty has been overcome by a recently in- troduced technique described by Engwall et al. (2006a). In brief the method uses the fact that for suitable conditions an enhanced wake is formed around the positively charged spacecraft. The wake disturbs the electric field measure- ments by the Cluster double probe experiment (Gustafsson et al., 2001). By comparing the electric field measurement signature of the wake with a model, the flow velocity can be determined. The wake does not disturb the electron drift in- strument EDI (Paschmann et al., 2001), which can be used to determine the perpendicular (E × B) plasma flow, mak- ing a decomposition of the plasma flow into its parallel and perpendicular parts possible. The density can be estimated from the spacecraft potential, so that the field-aligned flux of plasma can be determined. By applying this new method En- gwall et al. (2009b) could show that cold proton fluxes dom- inates in the distant lobes, out to 19 R E geocentric distance.
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A physical mechanism producing suprathermal populations and initiating substorms in the Earth's magnetotail

A physical mechanism producing suprathermal populations and initiating substorms in the Earth's magnetotail

Abstract. We suggest a candidate physical mechanism, combining there dimensional structure and temporal devel- opment, which is potentially able to produce suprathermal populations and cross-tail current disruptions in the Earth’s plasma sheet. At the core of the proposed process is the “akis” structure; in a thin current sheet (TCS) the stretched (tail-like) magnetic field lines locally terminate into a sharp tip around the tail midplane. At this sharp tip of the TCS, ions become non-adiabatic, while a percentage of electrons are accumulated and trapped: The strong and transient electro- static electric fields established along the magnetic field lines produce suprathermal populations. In parallel, the tip struc- ture is associated with field aligned and mutually attracted parallel filamentary currents which progressively become more intense and inevitably the structure collapses, and so does the local TCS. The mechanism is observationally based on elementary, almost autonomous and spatiotemporal en- tities that correspond each to a local thinning/dipolarization pair having duration of ∼1 min. Energetic proton and elec- tron populations do not occur simultaneously, and we infer that they are separately accelerated at local thinnings and dipolarizations, respectively. In one example energetic par- ticles are accelerated without any dB/dt variation and before the substorm expansion phase onset. A particular effort is un- dertaken demonstrating that the proposed acceleration mech- anism may explain the plasma sheet ratio T i /T e ≈7. All our
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Magnetic turbulence and particle dynamics in the Earth’s magnetotail

Magnetic turbulence and particle dynamics in the Earth’s magnetotail

The Earth’s magnetotail is a large reservoir of plasma and en- ergy, and is characterized by a magnetic configuration which leads to many intriguing nonlinear phenomena. In particu- lar, several spacecraft have observed phenomena as sudden plasma motions, current diversions, energetic particle bursts, and strong geomagnetic activity mixed with relatively quiet periods. The observations of ISEE 2, AMPTE/IRM, Geotail, Interball, and other spacecraft have shown the existence of plasma and magnetic field turbulence in the distant and near Earth’s magnetotail (Angelopoulos et al., 1993; Hoshino et al., 1994; Ohtani et al., 1995; Bauer et al., 1995; Borovsky et al., 1997). Usually, the turbulence is stronger in the cen- ter of the plasma sheet (Bauer et al., 1995; Hoshino et al., 1996), while a more regular magnetic configuration is found in the vicinity of the magnetospheric lobes. The observed Correspondence to: G. Zimbardo (zimbardo@fis.unical.it)
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Magnetotail response during a strong substorm as observed by GEOTAIL in the distant tail

Magnetotail response during a strong substorm as observed by GEOTAIL in the distant tail

study the response of the Earth's magnetotail during a strong substorm (AE  680 nT). At geosynchronous altitude, LANL spacecraft recorded three electron injections between 0030 UT and 0130 UT, which cor- respond to onsets observed on the ground at Kiruna Ground Observatory. The Earth's magnetotail respond- ed to this substorm with the ejection of ®ve plasmoids, whose size decreases from one plasmoid to the next. Since the type of magnetic structure detected by a spacecraft residing the lobes, depends on the Z extent of the structure passing underneath the spacecraft, GEO- TAIL is ®rst engulfed by a plasmoid structure; six minutes later it detects a boundary layer plasmoid (BLP) and ®nally at the recovery phase of the substorm GEOTAIL observes three travelling compression re- gions (TCRs). The time-of-¯ight (TOF) speed of these magnetic structures was estimated to range between 510 km/s and 620 km/s. The length of these individual plasmoids was calculated to be between 28 Re and 56 Re. The principal axis analysis performed on the magnetic ®eld during the TCR encountered, has con- ®rmed that GEOTAIL observed a 2-D perturbation in the X-Z plane due to the passage of a plasmoid underneath. The ®rst large plasmoid that engulfed GEOTAIL was much more complicated in nature probably due to the external, variable draped ®eld lines associated with high beta plasma sheet and the PSBL ¯ux tubes surrounding the plasmoid. From the analysis of the energetic particle angular distribution, evidence was found that ions were accelerated from the distant X-line at the onset of the burst associated with the ®rst magnetic structure.
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Plasma convection in the magnetotail lobes: statistical results from Cluster EDI measurements

Plasma convection in the magnetotail lobes: statistical results from Cluster EDI measurements

The procedure to determine the concurrent IMF orientation is identical to the procedure described in Haaland et al. (2007) and later used by F¨orster et al. (2007a). Basically, it con- sists of time shifting the measurements from the ACE space- craft, orbiting the L1 libration point, to the upstream magne- topause. For this purpose, we have applied the phase front propagation technique described in Weimer et al. (2003), al- though with a minor correction to the minimum variance cal- culation as suggested by Haaland et al. (2006), and later im- plemented in Weimer and King (2008). This technique takes the position of the solar wind monitor as well as the orienta- tion of the IMF into account when calculating the time shift. For time intervals without any distinct IMF discontinuities, this method is believed to give more precise time shifts than simpler methods (Weimer and King, 2008, see also discus- sion in Mailyan et al., 2008). The time shifted IMF informa- tion is thereafter filtered with a bias filter so that only mea- surements which are stable within a 30 min interval are used. The interval is meant to take into account possible errors in the time shift estimate as well as some time to set up the mag-
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	Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

41. Wang WL et al. The beneit of pretreatment esophageal screening with image-enhanced endoscopy on the survival of patients with hypopharyngeal cancer. Oral Oncol. 2013;49(8):808-13. 42. de Monès E et al; Socéité Française de l’Otorhinolaryngologie. Initial staging of squamous cell carcinoma of the oral cavity, larynx and pharynx (excluding nasopharynx). Part 2: Remote extension assessment and exploration for secondary synchronous locations outside of the upper aerodigestive tract. 2012 SFORL guidelines. Eur Ann Otorhinolaryngol Head Neck Dis. 2013;130(2):107-12.
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The role of business intelligence in decision process modeling

The role of business intelligence in decision process modeling

Another challenge is multiple classii cations when the customer belongs to more than one category. h ere is the case of web mining.h e Internet is get- ting the primate as a new channel for the goods dis- tribution, product promotion, transaction manage- ment and coordination of business processes and it becomes a valuable and suitable source of data about customers. More information on management can be seen in (Draker, 2003). However, multiple formats of data and distributive nature of knowledge on the Web are the challenge for collecting, revealing, organizing and knowledge management in the way that is suitable for providing support to business decision making. More information on decision support system can be seen in (Kotsiantis, 2011).
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Barium and sodium in sunflower plants cultivated in soil treated with wastes of drilling of oil well Jésus Sampaio Junior

Barium and sodium in sunflower plants cultivated in soil treated with wastes of drilling of oil well Jésus Sampaio Junior

the supply of soluble salts like Na and K was lower, causing lower influence on the development of sunflower plants. According to Munns (2002), plants cultivated under saline conditions show changes in the growth parameters associated with the osmotic, toxic and nutritional effects caused by the excess of salts in the soil. Nobre et al. (2010) observed linear reduction in plant height, stem diameter, shoot dry matter, beginning of flowering and diameter of capitula of sunflower, due to the salinity. Magalhães et al. (2014a) observed that rice plants cultivated in soils treated with oil well drill cuttings also showed reductions in growth and dry matter production with the increase in the waste dose, which were attributed to the high contents of Na in the waste.
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Braz. J. Chem. Eng.  vol.30 número4

Braz. J. Chem. Eng. vol.30 número4

Equations (1) to (5) establish the formulation developed for hydrocyclones when operating with Newtonian fluid-solid suspensions. The published literature on the operation of hydrocyclones using non-Newtonian fluids can be divided into two groups. The first group focuses on the experimental observa- tion of the separation phenomena that take place inside the equipment, presenting empirical equations for evaluation of its performance (Lynch and Rao, 1975; Plitt, 1971; Linch and Rao, 1968; Lynch et al., 1974; Rao et al., 1976; Lilge, 1961, 1962; Napier- Munn, 1980; Upadrashta and Venkateswarlu, 1983; Walker et al., 1992; Horsley et al., 1992; Yoshida et al., 2004). The second group focuses on the mathematical modeling of the fluid flow in the body of the hydrocyclone and also in the fluid boundary layer adjacent to the equipment internal walls. As a result of this approach, fluid velocity profiles are obtained by solving the momentum and continuity equations. These velocity profiles are used in the determination of the particle trajectory and, conse- quently, the collection efficiency of the equipment (Upadrashta et al., 1987; Barrientos and Concha, 1992; Dyakowski et al., 1994; Yablonskii, 2000; Tavares et al., 2002; Yablonskii, 2004; Yablonskii, 2005; Yablonskii and Ryabchuk, 2005; Brenan et.al., 2007; Davailles et. al., 2012).
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Study of acrosome formation, interspecific and intraspecific, in the testicular lobes of some pentatomid species

Study of acrosome formation, interspecific and intraspecific, in the testicular lobes of some pentatomid species

An essential structure of spermatozoa for the recognition and penetration of the ovum, inducing fertilization, is the acrosome that is formed by the Golgi apparatus (Phillips 1970; Baccetti 1972). The development of the acrosome begins with a spherical body, the pre-acrosomal granule. This structure results from the fusion of vesicles produced by the Golgi apparatus, and it is gradually modified until reaching its final form. The size, forms and internal structure of the mature acrosome vary among the different species of animals (Anderson and Personne 1975). More exact and detailed investigations in the Pentatomidae were carried out by Bowen (1922) who analyzed the bodies formed by the Golgi apparatus and the dictyosomes of the spermatocytes to the spermatozoa, and he showed that they are intimately involved in the formation process of the acrosome (Bowen 1922, 1924).
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Nigeria SMEs P articipation in  E lectronic  E conomy:  Problems and the  W ay  F orward

Nigeria SMEs P articipation in E lectronic E conomy: Problems and the W ay F orward

With all these developments, millions of people around the world now use the Internet for everything from doing homework to buying books, or playing or downloading games, music and movies. Levels of user participation and publication on the Internet have also surged, from blogs, podcasts and interactive wikis that anyone can modify, through to services for sharing photos and video clips, such as Flickr and Daily Motion. Social networking sites such as Bebo, Facebook and MySpace represent another rapidly developing frontier of communication. It is apparent that Internet-based applications underlie major advances in science, business organisation, environmental monitoring, transport management, education and e-government. Nowadays, without the Internet, planes would not fly, financial markets would not operate, supermarkets would not restock, taxes would not get paid and the power grid would not balance the supply and demand for electricity (Huttner, 2007).This reflects our increasing reliance on the Internet for business and social activity.
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Finding fundamental circuits in the network: A Matlab program and application in tumor pathway

Finding fundamental circuits in the network: A Matlab program and application in tumor pathway

Following Zhang (2012), if k links of a network are naturally arranged and thus generates a finited sequence, the sequence is called a chain. The chain with distinct initial node and terminal node is an open chain, or else it is a closed chain. A chain without repeated links is a simple chain. An open simple chain without repeated nodes is defined as the elementary chain, or path. Moreover, if there is at least a chain starting from initial node u to terminal node v, then the elementary chain starting from u to v exists. Given that the two endpoints of an elementary chain are the same node, the chain becomes a circuit. A circuit with length k is called the k- circuit. In present article, I will present full Matlab codes of the Paton algorithm for calculating fundamental circuit set and use it in tumor pathways.
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J. epilepsy clin. neurophysiol.  vol.17 número2

J. epilepsy clin. neurophysiol. vol.17 número2

Left and right cerebral hemispheres are morphologically similar, although they are functionally different. Focal EEG abnormalities should appear with an equal frequency in both of them, but the literature has reported a left predominance. We presented the first Latin American study on lateralization of focal EEG abnormalities. Method: We retrospectively studied 10,408 EEGs from April 2001 to April 2010. They were separated by age and gender to estimate the frequency of left-sided versus right-sided focal abnormalities (discharges or slow waves). Associated clinical features were also accessed. Results: Discharges were more prevalent in left cerebral hemisphere, in temporal lobe, and a stronger lateralization was found among adults. Right-sided discharges occurred more in frontal lobe. Slow waves were also more prevalent in the left cerebral hemisphere and among adults. Among left-sided slow waves group, women were more prevalent. Contrarily, men were more observed among right-sided slow waves EEGs. Left-sided slow waves were more prevalent in temporal and parietal lobes. Contrarily, right-sided slow waves occurred more in frontal and occipital lobes. Epilepsy was the most frequent disease among the patients with focal discharges in both cerebral hemispheres. Right-sided slow waves were more associated to epilepsy, and left-sided slow waves were more associated to headache. Conclusion: There were significant differences between cerebral hemispheres on focal EEG abnormalities, considering lateralization, gender, age and clinical features. These results suggest a neurofuncional asymmetry between cerebral hemispheres which may be explained by different specificities, as well as by cerebral neuroplasticity.
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Acceleration of electrons in the plasma wakefield of a proton bunch

Acceleration of electrons in the plasma wakefield of a proton bunch

(numbers NRF-2015R1D1A1A01061074 and NRF-2016R1A5A1013277); the Portuguese FCT—Foundation for Science and Technology, through grants CERN/FIS-TEC/0032/2017, PTDC-FIS-PLA-2940-2014, UID/FIS/50010/2013 and SFRH/IF/01635/2015; NSERC and CNRC for TRIUMF’s contribution; and the Research Council of Norway. M. Wing acknowledges the support of the Alexander von Humboldt Stiftung and DESY, Hamburg. For their advice and contributions to the development of the magnetic spectrometer, we acknowledge B. Biskup, P. La Penna and M. Quattri. A. Petrenko acknowledges G. Demeter (Wigner Institute, Budapest) for calculating the rubidium ionization probability at AWAKE. F. Keeble acknowledges the operators of the CLEAR facility for their assistance during the calibration of the spectrometer. The AWAKE collaboration acknowledge the SPS team for proton delivery. Reviewer information Nature thanks T. Tajima and the other anonymous reviewer(s) for their contribution to the peer review of this work.
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Optimizing laser-driven proton acceleration from overdense targets

Optimizing laser-driven proton acceleration from overdense targets

We demonstrate how to tune the main ion acceleration mechanism in laser-plasma interactions to collisionless shock acceleration, thus achieving control over the final ion beam properties (e. g. maximum energy, divergence, number of accelerated ions). We investigate this technique with three- dimensional particle-in-cell simulations and illustrate a possible experimental realisation. The setup consists of an isolated solid density target, which is preheated by a first laser pulse to initiate target expansion, and a second one to trigger acceleration. The timing between the two laser pulses allows to access all ion acceleration regimes, ranging from target normal sheath acceleration, to hole boring and collisionless shock acceleration. We further demonstrate that the most energetic ions are produced by collisionless shock acceleration, if the target density is near-critical, n e ≈ 0.5 n cr . A scaling of the laser
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The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

Based on the objectives to be achieved and problems that have been formulated, the method used is juridical- sociological. The juridical approach is intended to explore and study the legislation as a basis for a research, while the sociological approach is intended to explore the factors and impacts incurred from the occurrence of border-area dispute and solution by the government. The specifications of this research are normative law called also as doctrinal research. A site was chosen by researcher to conduct a research is a government agency that includes the Navy (Department of Hydro-Oceanographic) related to the sea boundaries of the Republic of Indonesia and neighboring countries, local governments, especially in the leading islands border to the Republic of Indonesia related to culture, security, politics and thinking about the area/island they occupy, as a part of the Unitary of the Republic of Indonesia. The population is all research objects to be researched. In this research, the population is Navy and the relevant agencies involved in the security of sea area. The samples were chosen to be a material of research is the bearer of the security function in marine areas through the random system and interviews with relevant parties, such as Bakorkamla and community.
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Hist. cienc. saudeManguinhos  vol.20 número4

Hist. cienc. saudeManguinhos vol.20 número4

The state of siege decreed during the Vaccine Revolt lasted three months and seven days (from November 16, 1904 to February 23, 1905). Although it was the fifth state of siege during the Republic, it was the first time it was decreed with the intention of suppressing a popular revolt. The related parliamentary debates were waged in two different periods: before the decree, due to the need to approve the request from the president to Congress, and after the state of siege ended, when they had to discuss the constitutionality of acts performed by the Executive in the interim. In the first set of discussions, debate was very limited due to the urgency of those supporting the government to approve the measure given the uprising at the Military Academy. However, on this occasion, demophobia was already apparent in the speech of the senator from Rio Grande do Sul, Ramiro Barcelos (16 nov. 1904), who described these events as “disorder created by a populace seduced by ambitious politicians who want, on any pretext, to make way for their ambitions of power.” It was the classic picture painted by Taine, of the crowd seduced by a handful of demagogues to destroy order in the name of egalitarianism. Senator Rui Barbosa, from Bahia, a progressive liberal critical of the oligarchic regime, who always fought the conservative interpretation of the state of siege and, during these discussions, mandatory vaccines, was in a difficult position. While acknowledging that popular resistance to the government was always just when no option to object by peaceful means was left, Barbosa believed that this was not the case in the revolt. It had been legitimate when spontaneous, but had stopped being so due to the politicization promoted by the Jacobins. Therefore, Barbosa felt obliged to not deny the request for a state of siege decree. It seemed to him that, at that moment, it was order and not freedom that was in danger from the military rebellion that intended to inaugurate a dictatorship in Brazil. Thus, while more progressive than the establishment grandees, Barbosa shared the view that, along with jeering, any popular uprising was always negative. He described the people as orderly and hardworking, who rose against the government at the instigation of demagogues.
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An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

Women also provide most of the labour for harvesting and post-harvest activities (FAO, 1996). Cassava is important, not only as a food crop but even more as a major source of income for rural households (Davies et al., 2008). As a cash crop, cassava generates cash income for the largest number of households in comparison with other staples. However the sustainability of this staple crop depends on the enormous availability of land for its cultivation. Land is the foundation of all human, social and economic activities that lie at the heart of social, political, or economic life of most nations especially African nations. Land is recognized as a primary source of wealth, social status and power, the basis for shelter, food, and economic activities and significantly provides employment opportunities in the rural areas. Land is fundamental to agriculture, yet the different challenges women face in accessing them are rarely fully addressed. For women, it is often particularly difficult to access, own or control land due to legal or cultural restrictions ( Emeasoba, 2012). This problem is widespread; women hold title to approximately two percent of land globally and are frequently denied the right to inherit property (World Bank, 2005). The wealth obtainable from cassava production, processing and marketing as a result of gender inequality remains under serious threat if nothing is done to improve the operating environmental and socio- economic conditions of the farmers in terms of asset holding, welfare and credit availability. The broad objective of the study is to analyze male and female access to land for cassava production in Abia state and specifically to describe the socio-economic characteristics of the respondents and the difference in quantity of cassava produced by both male and female respondents.
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Suppressing Fermi Acceleration in a Driven Elliptical Billiard

Suppressing Fermi Acceleration in a Driven Elliptical Billiard

FA is not a structurally stable phenomenon. We consider the dynamics of an ensemble of noninteracting particles in a time-dependent elliptical-like billiard. Our results show that initial conditions chosen along the separatrix curve of the billiard with a static boundary lead the particle to exhibit FA. Thus the LRA conjecture can be extended to the existence of a heteroclinic orbit in the phase space instead of the existence of a set with chaotic dynamics. The mechanism which produces FA, as discussed in [27], is the successive crossings by the particle of a neighborhood of a separatrix curve in the static case, which under time perturbation to the boundary turns into a stochastic layer. Such crossings change the dynamics of the particle from rotation to libration (or vice versa) and causes the kinetic energy of the particle to fluctuate. These fluctuations in- crease with time and lead to an anomalous diffusion and consequently to FA. Here we demonstrate that inelastic collisions of the particle with the boundary break down the mechanism of FA and therefore suppress the unlimited energy gain of the bouncing particle. The dissipation stops the successive crossings of the particle of the stochastic layer. This suppression confirms a conjecture [29] for suppression of FA in 2D billiards under inelastic collisions. The model under study consists of a classical particle confined to a closed domain whose boundary changes in time according to the following equation in polar coordi- nates
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Tracing the Origins of Brazil’s Great Acceleration

Tracing the Origins of Brazil’s Great Acceleration

scattered along the entire length of Brazil’s Amazonian border and along the banks of the Amazon River, the region’s main transport system. The Comissão hoped to create with these zones a tight web of inter- connected settlements, which, to the military’s satisfaction, would also contribute to reinforce Brazilian presence and control over formerly empty stretches of the national territory. Besides demonstrating Bra- zilian authority over Amazonia, these zones worked as testing benches within which the SPVEA’s experts could experiment with moderniza- tion. Their goal was as much to transform these zones into stable and thriving communities as it was to identify the ways and methods to scientifically engineer this transformative process. Each zone worked as an ideal-typical sample of the Amazonian bio-social landscape where planners could rationally identify and scientifically craft new socio- economic, but also technical, moral and human structures conducive of durable development. With zonaemento, they broke down the region’s social and natural landscape into experimental spaces within which they designed and applied a programme of modernization that could be replicated elsewhere in Brazil.
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