Non-radial solar wind flows induced by the motion of interplanetary coronal mass ejections

A survey of the non-radial flows (NRFs) during nearly five years of interplanetary observations revealed the average non-radial speed of the solar wind flows to be �30 km/s, with approximately one-half of the large (>100 km/s) NRFs associated with ICMEs. Conversely, the average non-radial flow speed upstream of all ICMEs is �100 km/s, with just over one-third preceded by large NRFs. These upstream flow deflections are analysed in the context of the large-scale structure of the driving ICME. We chose 5 magnetic clouds with relatively uncomplicated upstream flow deflections. Using variance analysis it was possible to infer the local axis orientation, and to qualitatively estimate the point of interception of the spacecraft with the ICME. For all 5 events the observed upstream flows were in agreement with the point of interception predicted by variance analysis. Thus we conclude that the upstream flow deflections in these events are in accord with the current concept of the large scale structure of an ICME: a curved axial loop connected to the Sun, bounded by a curved (though not necessarily circular)cross section.

Predictions of the arrival time of coronal mass ejections at 1AU: an analysis of the causes of errors

Three existing models of Interplanetary Coronal Mass Ejection (ICME) transit between the Sun and the Earth are compared to coronagraph and in situ observations: all three models are found to perform with a similar level of accuracy (i.e. an average error between observed and predicted 1AU transit times of approximately 11 h). To improve long-term space weather prediction, factors influencing CME transit are investigated. Both the removal of the plane of sky projection (as suffered by coronagraph derived speeds of Earth directed CMEs) and the use of observed values of solar wind speed, fail to significantly improve transit time prediction. However, a correlation is found to exist between the late/early arrival of an ICME and the width of the preceding sheath region, suggesting that the error is a geometrical effect that can only be removed by a more accurate determination of a CME trajectory and expansion. The correlation between magnetic field intensity and speed of ejecta at 1AU is also investigated. It is found to be weak in the body of the ICME, but strong in the sheath, if the upstream solar wind conditions are taken into account.

Characteristic magnetic field and speed properties of interplanetary coronal mass ejections and their sheath regions

Prediction of the solar wind conditions in near-Earth space, arising from both quasi-steady and transient structures, is essential for space weather forecasting. To achieve forecast lead times of a day or more, such predictions must be made on the basis of remote solar observations. A number of empirical prediction schemes have been proposed to forecast the transit time and speed of coronal mass ejections (CMEs) at 1 AU. However, the current lack of magnetic field measurements in the corona severely limits our ability to forecast the 1 AU magnetic field strengths resulting from interplanetary CMEs (ICMEs). In this study we investigate the relation between the characteristic magnetic field strengths and speeds of both magnetic cloud and noncloud ICMEs at 1 AU. Correlation between field and speed is found to be significant only in the sheath region ahead of magnetic clouds, not within the clouds themselves. The lack of such a relation in the sheaths ahead of noncloud ICMEs is consistent with such ICMEs being skimming encounters of magnetic clouds, though other explanations are also put forward. Linear fits to the radial speed profiles of ejecta reveal that faster-traveling ICMEs are also expanding more at 1 AU. We combine these empirical relations to form a prediction scheme for the magnetic field strength in the sheaths ahead of magnetic clouds and also suggest a method for predicting the radial speed profile through an ICME on the basis of upstream measurements.

Observational tracking of the 2D structure of coronal mass ejections between the sun and 1 AU

The Solar TErrestrial RElations Observatory (STEREO) provides high cadence and high resolution images of the structure and morphology of coronal mass ejections (CMEs) in the inner heliosphere. CME directions and propagation speeds have often been estimated through the use of time-elongation maps obtained from the STEREO Heliospheric Imager (HI) data. Many of these CMEs have been identified by citizen scientists working within the SolarStormWatch project ( www.solarstormwatch.com ) as they work towards providing robust real-time identification of Earth-directed CMEs. The wide field of view of HI allows scientists to directly observe the two-dimensional (2D) structures, while the relative simplicity of time-elongation analysis means that it can be easily applied to many such events, thereby enabling a much deeper understanding of how CMEs evolve between the Sun and the Earth. For events with certain orientations, both the rear and front edges of the CME can be monitored at varying heliocentric distances (R) between the Sun and 1 AU. Here we take four example events with measurable position angle widths and identified by the citizen scientists. These events were chosen for the clarity of their structure within the HI cameras and their long track lengths in the time-elongation maps. We show a linear dependency with R for the growth of the radial width (W) and the 2D aspect ratio (χ) of these CMEs, which are measured out to ≈ 0.7 AU. We estimated the radial width from a linear best fit for the average of the four CMEs. We obtained the relationships W=0.14R+0.04 for the width and χ=2.5R+0.86 for the aspect ratio (W and R in units of AU).

Heliospheric Observations of STEREO-Directed Coronal Mass Ejections in 2008 – 2010: Lessons for Future Observations of Earth-Directed CMEs

We present a study of coronal mass ejections (CMEs) which impacted one of the STEREO spacecraft between January 2008 and early 2010. We focus our study on 20 CMEs which were observed remotely by the Heliospheric Imagers (HIs) onboard the other STEREO spacecraft up to large heliocentric distances. We compare the predictions of the Fixed-Φ and Harmonic Mean (HM) fitting methods, which only differ by the assumed geometry of the CME. It is possible to use these techniques to determine from remote-sensing observations the CME direction of propagation, arrival time and final speed which are compared to in-situ measurements. We find evidence that for large viewing angles, the HM fitting method predicts the CME direction better. However, this may be due to the fact that only wide CMEs can be successfully observed when the CME propagates more than 100∘ from the observing spacecraft. Overall eight CMEs, originating from behind the limb as seen by one of the STEREO spacecraft can be tracked and their arrival time at the other STEREO spacecraft can be successfully predicted. This includes CMEs, such as the events on 4 December 2009 and 9 April 2010, which were viewed 130∘ away from their direction of propagation. Therefore, we predict that some Earth-directed CMEs will be observed by the HIs until early 2013, when the separation between Earth and one of the STEREO spacecraft will be similar to the separation of the two STEREO spacecraft in 2009 – 2010.

Near-earth cosmic ray decreases associated with remote coronal mass ejections

Galactic cosmic ray (GCR) flux is modulated by both particle drift patterns and solar wind structures on a range of timescales. Over solar cycles, GCR flux varies as a function of the total open solar magnetic flux and the latitudinal extent of the heliospheric current sheet. Over hours, drops of a few percent in near-Earth GCR flux (Forbush decreases, FDs) are well known to be associated with the near-Earth passage of solar wind structures resulting from corotating interaction regions (CIRs) and transient coronal mass ejections (CMEs). We report on four FDs seen at ground-based neutron monitors which cannot be immediately associated with significant structures in the local solar wind. Similarly, there are significant near-Earth structures which do not produce any corresponding GCR variation. Three of the FDs are during the STEREO era, enabling in situ and remote observations from three well-separated heliospheric locations. Extremely large CMEs passed the STEREO-A spacecraft, which was behind the West limb of the Sun, approximately 2–3 days before each near- Earth FD. Solar wind simulations suggest that the CMEs combined with pre-existing CIRs, enhancing the pre-existing barriers to GCR propagation. Thus these observations provide strong evidence for the modulation of GCR flux by remote solar wind structures.

Juvenile development and growth patterns in the mud crab Eurytium limosum (Say, 1818) (Decapoda, Brachyura, Xanthidae) under laboratory conditions

The post-larval development of the mud crab Eurytium limosum was studied under laboratory conditions by using the offspring of ovigerous females collected at the Comprido River mangrove, SP, Brazil. The first crab stage is fully described and the juvenile development, until crab stage 10, is examined with emphasis on morphological change, sexual differentiation and growth patterns. The carapace of the first crab stage is nearly square as observed in other xanthids, becoming similar to adults only at stage 15. The sexes can be distinguished from stage four, based on the number of pleopods and their morphology. While the intermoult period increases, the moult percentage decreases at each stage. The abdominal allometric growth is sex-dependent, with males showing a negative (b=0.71) and females an isometric (b=0.95) relative growth pattern. Male gonopods undergo a positive allometric growth, and their shape changes remarkably until sexual maturity. The cheliped dentition can be observed after stage 4. Regardless of sex, most crabs have a molariform right cheliped, which is thought to aid the handling of asymmetric prey such as gastropods.

A morphometric study of the mud crab, Panopeus austrobesus Williams, 1983 (Decapoda, Brachyura) from a subtropical mangrove in South America

The relative growth of the xanthid crab, Panopeus austrobesus was investigated by means of the allometric method. Crabs were obtained in the mangrove formed by the estuary of the rivers Comprido and Escuro (23degrees29'24S 45degrees10'12W), Ubatuba, São Paulo State, Brazil. All crabs were measured to obtain their carapace width (CW) and length (CL), abdomen width (AW) at the basis of the 5(th) somite, and major cheliped propodus length (PL) and height (PH). Males were also measured for their gonopod length (GL). The size of crabs based on CW ranged from 4.0 to 44.8 mm for males and 3.1 to 34.5 mm for females. The relative growth equation (Y = aX(b)) based on the relationship between GL and CW suggested that males reach their sexual maturity near 14.6 mm CW. Such relationship shows a positive allometry during the juvenile phase and an isometric growth in adult life. In females, the estimated size at 50% maturity is 13.0 mm CW, based on the relationship AW vs. CW. Males reach larger sizes than females, which probably provides them better conditions to protect females during courtship. Concerning cheliped size, approximately 73% of the crabs analysed (N = 209), disregarding sex, have the right PL larger than the left. The PL growth shows that specimens with a left major cheliped (26%) have a higher allometric coefficient, despite being smaller considering their CW. Such a difference may compensate the smaller size of the crab during defense or prey capture.

Acute and subchronic exposure of diplopods to substrate containing sewage mud: Tissular responses of the midgut

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ultrastructural Alterations in the Midgut of Diplopods after Subchronic Exposure to Substrate Containing Sewage Mud

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caste Differences in Polybia emaciata, a Mud-Nesting Eusocial Wasp (Hymenoptera: Vespidae), that Bear on Pre-Imaginal Determination but not Size Differences

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Red Mud from Brazil: Thermal Behavior and Physical Properties

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Probabilistic neural network to predict cracks in taphole mud used in blast furnaces

One of the major problems facing Blast Furnaces is the occurrence of cracks in taphole mud, as the underlying causes are not easily identifiable. The absence of this knowledge makes it difficult the use of conventional techniques for predictability and mitigation. This paper will address the application of Probabilistic Neural Network using the Matlab software as a means to detect and control such cracks. The most relevant BF operational variables were picked through the statistic tool "Principal Component Analysis - PCA." Based upon the selection of these variables a probabilistic neural network was built. A set of BF operational data, consisting of 30 controlling variables, was divided into 2 groups, one of which for network training, and the other one to validate the neural network. The neural network got 98% of the cases right. The results show the effectiveness of this tool for crack prediction in relation to clay intrinsic properties and as a result of the fluctuation in operational variables.

Ascomycetous yeasts from tropical intertidal dark mud of southeast Brazilian estuaries

Four different intertidal estuarine sediments had distinct yeast communities. One-hundred-ninety-three yeast isolates were classified in 47 species, with 34 of these in the genus Candida. Candida tropicalis was the only ascomycetous species isolated from all four sites. Other opportunistic pathogens including Candida glabrata, Candida guilliermondii, Candida parapsilosis and Candida krusei were present, especially at the more polluted sites. Pichia species were also frequent isolates with Pichia membranaefaciens, and its anamorph, Candida valida, and other phenotypically similar low assimilation profile species the most frequent. Kluyveromyces aestuarii was prevalent at the only site with well established mangrove vegetation, but not present at the other sites. The sediment yeast communities were distinct from each other, but more similar to each other than to the yeast communities of other ecosystems in the same geographic region.

Caste differences in Polybia ematiata, a mud-nesting eusocial wasp (hymenoptera: Vespidae), that bear on pre-imaginal determination but not size differences

The Epiponini is a group of social wasps living in polygynic societies. The caste dimorphism varies from incipient to well distinct. Morphometric analyses on twelve body parts and ovarian development of Polybia emaciata Lucas 1879, were used to estimate the level of caste differentiation in seven colonies. Physiologic differences were found. Among queens the ovaries were inseminated and presented as highly developed; in intermediate females, ovaries were slightly developed and uninseminated, and for the workers the ovaries were not developed or inseminated. In addition, the coloration of the mesosoma and metasoma were darker in workers and intermediates. Morphometric analysis evidenced slight morphological differences. Even though body proportions were not enough to discriminate castes, the fifth sternite of the gaster had important characters that were able to differentiate queens from workers and intermediates. We propose that P. emaciata presents a case of pre-imaginal caste determination, which is not strictly based on size.