Cooling and recombination processes in cometary plasma

The ion electron plasma in comets is examined for cooling processes which result from its interactions with the neutral coma. A cometary coma model is formulated that is composed predominantly of H2O and its decomposition products where electrons are cooled in a variety of processes at rates varying with energy. It is shown that solar plasma plus accumulated cometary ions and electrons is affected very strongly as it flows into the coma. The electrons are rapidly cooled and all but some 10% of the ions undergo charge exchange. Photodissociation of H2O is assumed where ion electron recombination is the dominant loss process

The Polonnaruwa meteorite: oxygen isotope, crystalline and biological composition

Results of X-Ray Diffraction (XRD) analysis, Triple Oxygen Isotope analysis and Scanning Electron Microscopic (SEM) studies are presented for stone fragments recovered from the North Central Province of Sri Lanka following a witnessed fireball event on 29 December 2012. The existence of numerous nitrogen depleted highly carbonaceous fossilized biological structures fused into the rock matrix is inconsistent with recent terrestrial contamination. Oxygen isotope results compare well with those of CI and CI-like chondrites but are inconsistent with the fulgurite hypothesis.Comment: 7 pages, 7 figures, 4 table

Prioritising the care of critically ill children: a pilot study using SCREEN reduces clinic waiting times

Objective In low-resource settings, childhood mortality secondary to delays in triage and treatment remains high. This paper seeks to evaluate the impact of the novel Sick Children Require Emergency Evaluation Now (SCREEN) tool on the waiting times of critically ill children who present for care to primary healthcare clinics in Cape Town, South Africa. Methods We used a pre/postevaluation study design to calculate the median waiting times of all children who presented to four randomly chosen clinics for 5 days before, and 5 days after, the implementation of SCREEN. Findings The SCREEN programme resulted in statistical and clinically significant reductions in waiting times for children with critical illness to see a professional nurse (2 hours 45 min to 1 hour 12 min; p<0.001). There was also a statistically significant reduction in the proportion of children who left without being seen by a professional nurse (25.8% to 18.48%; p<0.001). Conclusions SCREEN is a novel programme that uses readily available laypersons, trained to make a subjective assessment of children arriving at primary healthcare centres, and provides a low cost, simple methodology to prioritise children and reduce waiting times in low-resource healthcare clinics

Determining the Maternal and Fetal Cellular Immunologic Contributions in Preterm Deliveries With Clinical or Subclinical Chorioamnionitis

Objective: Our purpose was to determine the maternal and fetal polymorphonuclear contributions to preterm histologic chorioamnionitis and whether this response differs in clinical chorioamnionitis when compared to cases without clinical chorioamnionitis

Pasts and pagan practices: moving beyond Stonehenge

Theorizing the past is not restricted to archaeology and interpretations of 'past' both influence and are themselves constituted within politicized understandings of self, community and in certain instances, spirituality. 'The past in the imagination of the present' is appropriated, variously, to give meaning to the present or to justify actions and interpret experiences. Summer solstice at Stonehenge, with an estimated 21,000 celebrants in 2005, is only the most publicized appropriation (by pagans and other adherents of alternative spirituality and partying) of a 'sacred site'; and conflicts and negotiations occurring throughout Britain are represented in popular and academic presentations of this 'icon of Britishness'. This paper presents work from the Sacred Sites, Contested Rites/Rights Project (http://www.sacredsites.org.uk) project, a collaboration of archaeology and anthropology informed by pagan and alternative approaches and standpoints investigating and theorizing discourse and practice of heritage management and pagan site users. Whether in negotiations around the Stonehenge solstice access or in dealing with numerous other sites, boundaries between groups or discourses are not clearly drawn - discursive communities merge and re-emerge. But clearly 'past' and 'site' are increasingly important within today's Britain, even as television archaeology increases its following, and pagan numbers continue to grow.</p

Output of a pulsed atom laser

We study the output properties of a pulsed atom laser consisting of an interacting Bose-Einstein condensate (BEC) in a magnetic trap and an additional rf field transferring atoms to an untrapped Zeeman sublevel. For weak output coupling we calculate the dynamics of the decaying condensate population, of its chemical potential and the velocity of the output atoms analytically.Comment: 4 pages, RevTeX. Full ps file available on http://mpqibmr1.mpq.mpg.de:5000/~man

Quantitative Trait Locus (QTL) involved in the resistance of barley (Hordeum vulgare L.) to the mildew under different water treatments, in semi-arid Mediterranean region

In the present study we evaluated the contribution of molecular marking to the breeding of barley ( Hordeum vulgare L.) for resistance to the mildew ( Erysiphe graminis sp L. hordei ) in semi-arid Mediterranean region. For this study a F8 progeny of 167 recombinants inbred lines (RILs) from two row barley was cultivated at the experimental station of the National Institute of Agronomic Research of Tunisia (INRAT), at Kef during the cropping season of 1999/2000. The trials, in a completely randomized design, were conducted under three water treatments: (1) irrigation at seedling emergence, (2) no water addition and (3) irrigation at first observation of water stress symptoms. Assessment of natural infection by mildew of was made every fifteen days starting from the day when water treatments were setup. Statistical analyses of data showed a high among progeny variation within the progeny of RILs regardless a water treatments; however plants of treatment 1 (irrigation since seedling emergence) appeared to be the most susceptible. A combination of data on susceptibility of barley to natural infection by mildew and data from the genetic map generated from the crossing of Er/Apm vs Tadmor (parents of the 167RILs) allowed the detection and localization of several QTLs on chromosomes 3(3H), 4(4H) and 7(5H) of the barley. The most significant QTLs were located on the longer arm of chromosome 4(4H); on a portion where several authors have located reaction genes of barley to E. graminis. Overall, our results showed that the detection of QTL responsible of the expression of the resistance to E. graminis seemed to be intimately linked to the initial cropping conditions (e.g. temperature and optimum humidity). Indeed, no primary QTL were observed for dry conditions treatment (no irrigation). Moreover, the available literature reports did not allow us to confirm the relative situations of the secondary QTLs found for these treatments. Thus, genes of resistance to E. graminis would express themselves only in conditions that are favorable for the development of the pathogen. Improving the resistance of barley to mildew infection requires therefore, by a good knowledge on the process that governs expression of these genes