The present study integrates several aspects of a parasitological survey in a rural community village combining community knowledge of parasites, their potential transmission routes and health risk factors. A rural community located in Northern Thailand was surveyed for intestinal parasites, and an overall prevalence of 45.2% for helminths and 4.8% for protozoan infections was identified. Socio-demographic characteristics, customs and perceptions were compiled using individual questionnaires and interviews for participants surveyed for parasitic screening. The results allowed us to determine the knowledge and perception of local people concerning helminthic infection and transmission. Despite the fact that the participants in this community were aware of parasitic transmission routes, their widespread custom of eating raw fish and meat render the reduction of helminthiasis difficult. A detailed study on the infection of fish-borne parasitic trematodes, the most prevalent helminth, allowed us to determine that the distance from a given household to the river is a determinant of infection intensity. Health education activities organised in the local community resulted in a change in perception of risks associated with parasite transmission.

We present new results on extraplanar DIG (eDIG), based on high spatial resolution narrowband imaging observations of four late-type, actively star-forming edge-on spirals, obtained with ACS on-board HST. Our Hα observations reveal a multitude of structures on both small and large scales. Whereas all four galaxies have been studied with ground-based telescopes before, here the small scale structure of the extended emission line gas is presented for the very first time at a spatial resolution of 0.05′′, corresponding to 5 pc at the mean distance to our galaxies. The eDIG morphology is very different for all four targets, as a result of their different star formation activity and galaxy mass. There is a very smooth DIG morphology observed in two of the galaxies (NGC 4634 and NGC 5775), whereas the other two (NGC 4700 and NGC 7090) show a much more complex morphology with intricate filaments, and bubbles and supershells. We find that the morphology of the eDIG, in particular the break-up of diffuse emission into filaments in galaxy halos, shows a strong dependence on the level of star formation activity per unit area, and eDIG can be arranged into a morphological sequence.

INTRODUCTION

The shore crab, Carcinus maenas (L.), rapidly clears bacteria from the circulation to the tissues by virtue of the phagocytic and clumping capacity of circulating haemocytes and fixed phagocytic cells (Smith & Ratcliffe, 1978, 1980a, b; White & Ratcliffe, 1982). If re-infection resulting from the re-entry of sequestered micro-organisms into the circulation is to be prevented then the host must eliminate or incapacitate the foreign particles in some way. The migration of laden host cells to the exterior does not appear to be an important means of disposal of segregated non-self material in the Crustacea (Merril, Mongeon & Fisher, 1979; White & Ratcliffe, 1982), so that the ability to resist infection must reside with the cellular killing capacity, perhaps augmented by humoral antibacterial activity. Indeed, our earlier observations on the disappearance of bacteria from C. maenas gills seem to indicate that their loss resulted from the lytic action of host haemocytes (White & Ratcliffe, 1982), as does the elimination of micro-organisms from the hepatopancreas of the crayfish, Parachaeraps bicarinatus (McKay & Jenkin, 1970a).

High-resolution, multi-wavelength (UV through NIR) imaging from the Hubble Space Telescope has been obtained for three mergers in the Toomre Sequence, NGC 520, NGC 2623, & NGC 3256, to identify and measure the properties of young Globular Cluster (GC) candidates. Unlike previous merger studies, this work focuses on objects that lie in the middle of the Toomre Sequence. This age range represents a critical dynamical transition in the merging sequence between ongoing mergers and advanced remnants with properties more akin to elliptical galaxies. The early results of our investigation include luminosity functions and age-dating of the GC candidates. These results also address the impact of the dynamical state of the merger on the current young cluster population as compared with earlier studies that have dealt with the very oldest and very youngest mergers in the Toomre Sequence.

We investigate the relation between the existence and size of radio halos, which are believed to be created by star formation (SF) related energy input into the interstellar medium, and other galaxy properties, most importantly star formation activity and galaxy mass. Based on radio continuum and Hα observations of a sample of seven galaxies we find a direct, linear correlation of the radial extent of gaseous halos on the size of the actively star-forming parts of the galaxy disks. Data of a larger sample of 22 galaxies indicate that the threshold energy input rate into the disk ISM per unit surface area for the creation of a gaseous halo depends on the mass surface density of the galaxy, in the sense that a higher (lower) threshold has to be surpassed for galaxies with a higher (lower) surface density. Because of the good prediction of the existence of a radio halo from these two parameters, we conclude that they are important, albeit not the only contributors. The compactness of the SF-related energy input is also found to be a relevant factor. Galaxies with relatively compact SF distributions are more likely to have gaseous halos than others with more widespread SF activity. These results quantify the so-called “break-out” condition for matter to escape from galaxy disks, as used in all current models of the interstellar medium.

More details can be found Dahlem, Lisenfeld & Rossa, 2006, A&A 457, 121.

Cement samples containing variable amounts of Cr(III) or Ni(II) or Cd(II) as chloride admixtures present in a MLW stream from reprocessing of spent fuel were prepared under established procedure. Due to the high pH generated in the cement clinker hydration, respective metal hydroxides are formed and improve the physical characteristics of the cement matrix. An increase in the value of the compressive strength was observed when about 7% of the above elements were blended in cement. The increase depends on the nature of the element in the sequence Cr >Ni >Cd.

The leach tests confirm the formation of insoluble hydroxide presenting a low concentration in the leachate corresponding to 0.05, 0.004 and 0.052 mg.L−1 for Cr, Ni and Cd, respectively. On the other hand, the hydro-lyzed chloride ions seem to react with calcium with consequent increased degradation of the cement matrix.