Saving out of Different Types of Income

macroeconomics, financial savings,

The response of the magnetosphere to the passage of a coronal mass ejection on March 20-21 1990

International audienceThe geomagnetic response to the passage of a coronal mass ejection (CME) is studied. The passage of the CME resulted in a storm sudden commencement (SSC) at 2243 UT on March 20 1990 with disturbed magnetic activity during the following 24 h. The auroral, sub-auroral and equatorial magnetic response to the southward turning at 1314 (±5) UT on March 21 and the equatorial response to the southward turning associated with the SSC on 20 March are discussed in terms of existing models. It is found that the auroral and sub-auroral response to the southward turning associated with the SSC is a factor 2 or more quicker than normal due to the shock in the solar wind dynamic pressure. The low-latitude response time to the southward turning, characterised by Dst and the magnetopause current corrected Dst*, is unaffected by the shock. Dst and Dst*, characteristic of the equatorial magnetic field, responded to the 1314 (±5) UT southward turning prior to the first observed substorm expansion phase onset, suggesting that a dayside loading process was responsible for the initial enhancement in the ring current rather than nightside particle injection. The response time of the auroral and sub-auroral magnetic field to the southward turning at 1314 (±5) UT on March 21 is measured at a variety of longitudes and latitudes. The azimuthal propagation velocity of the response to the southward turning varied considerably with latitude, ranging from ~8 km s?1 at 67°N to ~4 km s?1 at 55°N. The southward velocity of the equatorward boundary of the northern polar convection pattern has been measured. This velocity was ~1.2 km s?1 at 1600 MLT, although there was evidence that this may vary at different local times

Applicability of mechanical tests for biomass pellet characterisation for bioenergy applications

In this paper, the applicability of mechanical tests for biomass pellet characterisation was investigated. Pellet durability, quasi-static (low strain rate), and dynamic (high strain rate) mechanical tests were applied to mixed wood, eucalyptus, sunflower, miscanthus, and steam exploded and microwaved pellets, and compared to their Hardgrove Grindability Index (HGI), and milling energies for knife and ring-roller mills. The dynamic mechanical response of biomass pellets was obtained using a novel application of the Split Hopkinson pressure bar. Similar mechanical properties were obtained for all pellets, apart from steam-exploded pellets, which were significantly higher. The quasi-static rigidity (Young’s modulus) was highest in the axial orientation and lowest in flexure. The dynamic mechanical strength and rigidity were highest in the diametral orientation. Pellet strength was found to be greater at high strain rates. The diametral Young’s Modulus was virtually identical at low and high strain rates for eucalyptus, mixed wood, sunflower, and microwave pellets, while the axial Young’s Modulus was lower at high strain rates. Correlations were derived between the milling energy in knife and ring roller mills for pellet durability, and quasi-static and dynamic pellet strength. Pellet durability and diametral quasi-static strain was correlated with HGI. In summary, pellet durability and mechanical tests at low and high strain rates can provide an indication of how a pellet will break down in a mill

Parsec-scale Properties of Brightest Cluster Galaxies

We present new VLBI observations at 5 GHz of a complete sample of Brightest Cluster Galaxies (BCGs) in nearby Abell Clusters (distance class <3). Combined with data from the literature, this provides parsec-scale information for 34 BCGs. Our analysis of their parsec scale radio emission and cluster X-ray properties shows a possible dichotomy between BCGs in cool core clusters and those in non cool core clusters. Among resolved sources, those in cool core clusters tend to have two-sided parsec-scale jets, while those in less relaxed clusters have predominantly one-sided parsec-scale jets. We suggest that this difference could be the result of interplay between the jets and the surrounding medium. The one-sided structure in non cool core clusters could be due to Doppler boosting effects in relativistic, intrinsically symmetric jets; two-sided morphology in cool core clusters is likely related to the presence of heavy and mildly relativistic jets slowed down on the parsec-scale. Evidence of recurrent activity are also found in BCGs in cool core clusters.Comment: 20 pages, 10 figures, accepted for publication in A&

South-north asymmetry of field-aligned currents in the magnetotail observed by Cluster

We statistically investigated features of the field-aligned current (FAC) distribution in plasma sheet boundary layers between 17 and 19 RE in the magnetotail using the curlometer technique to calculate the current from four-point magnetic field measurements taken in 2001. The results show that the FAC distribution in the plasma sheet boundary layers in the magnetotail has dusk-dawn asymmetry, earthward-tailward (polarity) asymmetry, and north-south asymmetry. The occurrence and polarities of FACs in the Northern Hemisphere are different from those in the Southern Hemisphere. The average density and the standard deviation of the FACs that are most likely to be connected to the Earth are 4.90 nA m−2 and 2.55 nA m−2 in the Northern Hemisphere and 4.21 nA m−2 and 1.80 nA m−2 in the Southern Hemisphere, respectively. For investigating the mechanism of the north-south asymmetry, we mapped the FACs along the field line into the polar region. The footprints of the FACs also show a difference between the Southern and Northern hemispheres (as a function of mapped latitude). These characteristics suggest a north-south asymmetry of the FACs in the magnetosphere. Further investigation is needed to identify the causes of this asymmetry, although the configuration of the magnetosphere, the polar cap boundary, the conductivity in the ionosphere, or the various solar wind-magnetosphere interaction processes all may be contributors. That the FAC densities are different between the hemispheres suggests that an important source of these currents must be a voltage generator

A Kaleidoscope of Decisions: Using Cognitive Flexibility Theory to Advance a Novice ESOL Teacher\u27s Scaffolding Expertise

Instructional scaffolding is a powerful tool that many teachers utilize to meet the challenge of individualizing instruction for diverse learners. The concept of instructional scaffolding is complex (Meyer, 1993), in that teachers have to determine what, how much, and what kind of help to give to students in a moment’s notice (Rodgers, 2004/05). Gaining expertise with scaffolding can take years, which leads us to worry about the effectiveness of novice teachers. A scarcity of research examining how to support a teacher’s development of instructional decisions such as scaffolding is reported (Anders, Hoffman, & Duffy, 2000). The ability to make scaffolding decisions requires teachers to be cognitively flexible, drawing from multiple domains of understanding to meet the individual needs of a group of students. However, little is known about which domains and understandings teachers draw on during scaffolding events or the rationales underlying this decision-making process. This naturalistic study examined the decision-making processes of a novice elementary ESOL teacher as she scaffolded instruction for her third-grade students. As she videotaped what she considered to be a successful scaffolding event each week, we unpacked the event together using the lens of Cognitive Flexibility Theory (CFT). The guiding questions were: (1) How can the decision-making processes underlying a novice ESOL teacher’s instructional scaffolding be described? (2) How can the lens of Cognitive Flexibility Theory inform a novice ESOL teacher’s scaffolding decisions? Data sources included interviews, field notes, and reflections of the sessions. Constant comparative analysis (Glaser & Strauss, 1967; Miles & Huberman, 1994) was used to analyze data. Rigor was demonstrated by establishing credibility, transferability, dependability, and confirmability (Lincoln and Guba). A grounded theory model of a kaleidoscope was created to describe the novice ESOL teacher’s decision-making processes during scaffolding events. The participant’s decisions were influenced by a variety of pedagogical and contextual domains while also being impacted by her views on scaffolding, on assessment, and on the connection between theory and practice. The participant’s conceptions of scaffolding became more complex and her confidence and sense of agency became stronger as a result of mentoring underpinned by CFT