A Potts model for the distortion transition in LaMnO3_3

The Jahn-Teller distortive transition of \lmo is described by a modified 3-state Potts model. The interactions between the three possible orbits depends both on the orbits and their relative orientation on the lattice. Values of the two exchange parameters which are chosen to give the correct low temperature phase and the correct value for the transition temperature are shown to be consistent with microscopy theory. The model predicts a first order transitions and also a value for the entropy above the transition in good agreement with experiment. The theory with the same parameters also predicts the temperature dependence of the order parameter of orbital ordering agreeing well with published experimental results. Finally, the type of the transition is shown to be close to one of the most disordered phases of the generalised Potts model. The short range order found experimentally above the transition is investigated by this model.Comment: 16 pages, 7 figures and no tables. Re-submitted to Phys. Rev.

Evaluation of the probiotic potential of lactic acid bacteria isolated from faeces of breast-fed infants in Egypt

The probiotic-related characteristics of 55 strains of lactic acid bacteria isolated from the faeces of 3 - 6 months old breast-fed infants were determined. The API 50 CH and SDS-PAGE techniques wereemployed to ascertain the identity of the isolated strains. The predominant species among the isolated strains were Lactobacillus (Lb.) acidophilus, Lb. plantarum, Enterococcus (E.) faecium, and E. faecalis. Probiotic properties such as bile resistance, acid tolerance, and adhesion to intestinal mucous were assessed. In vitro results obtained showed that five strains, Lb. plantarum (P1 and P164), Lb. pentosus (P191), and Lb. fermentum (P10, P193) were able to meet the basic requirements for probiotic functions as they demonstrated probiotic characteristics such as tolerance to pH 3, growth in 0.4% oxgall and adhesion to intestinal mucous. The results obtained in this investigation will be used to selectpotentially probiotic strains for in vivo study

Comparison of the accuracy of two scoring systems in predicting the outcome of organophosphate intoxicated patients admitted to intensive care unit (ICU)

AbstractIntroductionOrganophosphates(OP) are one of the most common causes of poisoning, especially in developing countries, with high morbidity and mortality. As mortality rate of OP poisoning is still high, early diagnosis and appropriate treatment is often life saving. OP is the main cause of poisoning and death in the poison control centre (PCC), Ain Shams University (ASU) in Egypt.ObjectiveTo compare the accuracy of acute physiology and chronic health evaluation score (APACHE IV) and simplified acute physiology score (SAPS II) in the prediction of mortality of patients with organophosphate poisoning (OPP) who required admission to the Intensive Care Unit (ICU) of PCC of ASU between January 1st, 2009 and December 31st, 2009.MethodsA prospective study conducted by collecting data on consecutive patients with acute OPP admitted to the intensive care unit over 12months. Data required to calculate the patients’ predicted mortality by (APACHE) IV and (SAPS) II scoring systems were collected.ResultsNinety patients were recruited in the study with acute OP toxicity. The observed mortality following acute OP toxicity was 13.3% (12 patients). The area under the receiver operator characteristic (ROC) curves of APACHE IV score was better than SAPS II score (0.921±0.054 SE, 0.807±0.078 SE, respectively). APACHE IV and SAPS II scores were significantly higher in the non-survival than in the survival group (P<0.05).ConclusionAPACHE IV and SAPS II scores calculated within the first 24h are good prognostic indicators among patients with acute OP toxicity that required ICU admission with preference to APACHE IV score. APACHE IV and SAPS II scores above 89, 44, respectively within the first 24h are a predictor of poor outcome in patients with acute OP toxicity.RecommendationApplication of APACHE IV and SAPS II scores is a good predictor of high mortality in OP intoxicated patients which helps in proper allocation of resources

Solar Flares and Coronal Mass Ejections: A Statistically Determined Flare Flux-CME Mass Correlation

In an effort to examine the relationship between flare flux and corresponding CME mass, we temporally and spatially correlate all X-ray flares and CMEs in the LASCO and GOES archives from 1996 to 2006. We cross-reference 6,733 CMEs having well-measured masses against 12,050 X-ray flares having position information as determined from their optical counterparts. For a given flare, we search in time for CMEs which occur 10-80 minutes afterward, and we further require the flare and CME to occur within +/-45 degrees in position angle on the solar disk. There are 826 CME/flare pairs which fit these criteria. Comparing the flare fluxes with CME masses of these paired events, we find CME mass increases with flare flux, following an approximately log-linear, broken relationship: in the limit of lower flare fluxes, log(CME mass)~0.68*log(flare flux), and in the limit of higher flare fluxes, log(CME mass)~0.33*log(flare flux). We show that this broken power-law, and in particular the flatter slope at higher flare fluxes, may be due to an observational bias against CMEs associated with the most energetic flares: halo CMEs. Correcting for this bias yields a single power-law relationship of the form log(CME mass)~0.70*log(flare flux). This function describes the relationship between CME mass and flare flux over at least 3 dex in flare flux, from ~10^-7 to 10^-4 W m^-2.Comment: 28 pages, 16 figures, accepted to Solar Physic