The Planetary Nebulae Luminosity Function and distances to Virgo, Hydra I and Coma clusters

The luminosity function of planetary nebulae populations in galaxies within 10-15 Mpc distance has a cut-off at bright magnitudes and a functional form that is observed to be invariant in different galaxy morphological types. Thus it is used as a secondary distance indicator in both early and late-type galaxies. Recent deep surveys of planetary nebulae populations in brightest cluster galaxies (BCGs) seem to indicate that their luminosity functions deviate from those observed in the nearby galaxies. We discuss the evidence for such deviations in Virgo, and indicate which physical mechanisms may alter the evolution of a planetary nebula envelope and its central star in the halo of BCGs. We then discuss preliminary results for distances for the Virgo, Hydra I and Coma clusters based on the observed planetary nebulae luminosity functions.Comment: 5 pages, one figure. To appear on the Proceedings of the IAU Symp. 289 "Advancing the physics of cosmic distances

Protective Effect of Ascorbic Acid, Biopropolis and Royal Jelly against Aluminum Toxicity in Rats Magda E. Mahmoud1 and Samaa S. Elsoadaa2*

The present study was conducted to investigate the effectiveness of ascorbic acid (AA), biopropolis and royal jelly in alleviating the toxicity of Aluminum chloride (AlCl3) on body weight gain, feed efficiency and biochemical parameters in rats with hostological examination of sections from liver and kidney. Thirty female Wistar–Albino rats (160-170 g) were randomly divided into five equal groups of six rats each. As normal drinking water was given to the control group, while the four groups II, III, IV and V received 34 mg AlCl3/ L in drinking water daily. Group II received only AlCl3. Group III, IV and V were administrated orally with ascorbic acid, biopropolis and royal jelly, respectively at a dose 50 mg/kg bw twice a week for 8 weeks. AlCl3 decreased significantly body weight gain and feed efficiency. While treatment of ascorbic acid (AA), propolis and royal plus AlCl3 normalized their to control value. The relative weight (percent of body weight) of liver and kidney increased when compared with control while the brain did not illustrate any change. The level of urea, and the activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and alanine aminotransferase (ALT) were increased, while total protein and albumin were decreased in serum of rats treated with AlCl3. It can be concluded that ascorbic acid, propolis and royal jelly have beneficial influences and could be able to antagonize AlCl3 toxicity. Keywords: Aluminum chloride: toxicity: ascorbic acid: biopropolis: royal jelly: rats

Structural and dielectric studies of the phase behaviour of the topological ferroelectric La1-xNdxTaO4

We thank the University of St Andrews and EPSRC (via DTG studentships to CALD and JG) for funding,The layered perovskite LaTaO4 has been prepared in its polar orthorhombic polymorphic form at ambient temperature. Although no structural phase transition is observed in the temperature interval 25° C < T < 500 °C, a very large axial thermal contraction effect is seen, which can be ascribed to an anomalous buckling of the perovskite octahedral layer. The non-polar monoclinic polymorph can be stabilised at ambient temperature by Nd-doping. A composition La0.90Nd0.10TaO4 shows a first-order monoclinic-orthorhombic (non-polar to polar) transition in the region 250° C < T < 350 °C. Dielectric responses are observed at both the above structural events but, despite the ‘topological ferroelectric’ nature of orthorhombic LaTaO4, we have not succeeded in obtaining ferroelectric P–E hysteresis behaviour. Structural relationships in the wider family of AnBnX3n+2 layered perovskites are discussed.Publisher PDFPeer reviewe

Genetic factors regulating lung vasculature and immune cell functions associate with resistance to pneumococcal infection

Streptococcus pneumoniae is an important human pathogen responsible for high mortality and morbidity worldwide. The susceptibility to pneumococcal infections is controlled by as yet unknown genetic factors. To elucidate these factors could help to develop new medical treatments and tools to identify those most at risk. In recent years genome wide association studies (GWAS) in mice and humans have proved successful in identification of causal genes involved in many complex diseases for example diabetes, systemic lupus or cholesterol metabolism. In this study a GWAS approach was used to map genetic loci associated with susceptibility to pneumococcal infection in 26 inbred mouse strains. As a result four candidate QTLs were identified on chromosomes 7, 13, 18 and 19. Interestingly, the QTL on chromosome 7 was located within S. pneumoniae resistance QTL (Spir1) identified previously in a linkage study of BALB/cOlaHsd and CBA/CaOlaHsd F2 intercrosses. We showed that only a limited number of genes encoded within the QTLs carried phenotype-associated polymorphisms (22 genes out of several hundred located within the QTLs). These candidate genes are known to regulate TGFb signalling, smooth muscle and immune cells functions. Interestingly, our pulmonary histopathology and gene expression data demonstrated, lung vasculature plays an important role in resistance to pneumococcal infection. Therefore we concluded that the cumulative effect of these candidate genes on vasculature and immune cells functions as contributory factors in the observed differences in susceptibility to pneumococcal infection. We also propose that TGFbmediated regulation of fibroblast differentiation plays an important role in development of invasive pneumococcal disease.This work was supported by the European Union-funded Pneumopath Project HEALTH-F3-2009-222983. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer-reviewedPublisher Versio

Porque as algas e bactérias não são amplamente reconhecidas como seres fotossintetizantes?

Com a intenção de valorizar um conhecimento que nos permita olhar para o mundo de modo global para compreender a nossa realidade, destinamos para esse estudo indicar que as algas e bactérias não são valorizadas como organismos fotossintetizantes em alguns artigos acadêmicos. Uma das possibilidades para que esses seres não sejam contemplados, no ensino, é o fato de tentarmos fragmentar os conhecimentos tendo como finalidade simplificar a aprendizagem. Porém, isso acaba por acarretar a descontextualização e consequentemente a ausência de sentido

An implicit finite difference approximation for the solution of the diffusion equation with distributed order in time

In this paper we are concerned with the numerical solution of a diffusion equation in which the time order derivative is distributed over the interval [0,1]. An implicit numerical method is presented and its unconditional stability and convergence are proved. A numerical example is provided to illustrate the obtained theoretical results

The Influence of Macroeconomic Factors on Stock Market Index (Study on Lq45 Index for August 2011–july 2016)

Penelitian ini bertujuan untuk mengamati pengaruh simultan dan parsial factor ekonomi makro yang diantaranya adalah harga minyak dunia, nilai tukar, tingkat inflasi dan tingkat suku bunga terhadap indeks LQ45. Penelitiаn ini menggunаkаn explаnаtory reseаrch dengаn pendekаtаn kuаntitаtif, dengаn 60 jumlаh sаmpel selаmа 10 periode indeks LQ45 pаdа Аgustus 2011 – Juli 2016. Dаtа yаng digunаkаn аdаlаh dаtа sekunder dengаn tipe dаtа time series. Аnаlisа yаng digunаkаn dаlаm penelitiаn ini аdаlаh аnаlisis deskriptif, inferensiаl stаtistik dаn regresi lineаr bergаndа. Hаsil penelitiаn menunjukkаn bаhwа 1) Vаriаbel ekonomi mаkro hаrgа minyаk duniа, nilаi tukаr, tingkаt inflаsi dаn tingkаt suku bungа memiliki pengаruh signifikаn secаrа simultаn terhаdаp indeks hаrgа sаhаm, indeks LQ45; 2) Vаriаbel hаrgа minyаk duniа tidаk memiliki pengаruh secаrа pаrsiаl terhаdаp indeks LQ45; 3) Vаriаbel nilаi tukаr memiliki pengаruh positif dаn signifikаn secаrа pаrsiаl terhаdаp indeks LQ45; 4) Vаriаbel tingkаt inflаsi tidаk memiliki pengаruh secаrа pаrsiаl terhаdаp indeks LQ45; 5) Vаriаbel tingkаt suku bungа memiliki pengаruh negаtive dаn signifikаn secаrа pаrsiаl terhаdаp indeks LQ45. Kata Kunci: Indeks LQ45, Harga Minyak Dunia, Nilai Tukar, Tingkat Inflasi, Tingkat Suku Bunga ABSTRАCT This research aims to observe the simultaneous and partial effect of macroeconomic factors which are world oil price, exchange rate, inflation rate and interest rate on LQ45 index. This reseаrch uses explаnаtory reseаrch аnd quantitative approach with the totаl of 60 samples for 10 periods of LQ45 index from Аugust 2011-July 2016. The dаtа collection method is using documentаtion with secondary time series dаtа. The аnаlysis method for this reseаrch is using descriptive аnаlysis, inferentiаl stаtistics аnd multiple lineаr regression. The results show thаt 1) The world oil price, exchаnge rаte, inflаtion rаte аnd interest rаte vаriаbles hаve а significаnt effect on LQ45 index simultаneously; 2) The vаriаble world oil price hаs no significаnt effect on LQ45 index pаrtiаlly; 3) The vаriаble exchаnge rаte hаs а positive аnd significаnt effect on LQ45 index pаrtiаlly; 4) The vаriаble level of inflаtion rаte hаs no significаnt effect on LQ45 index pаrtiаlly; 5) The vаriаble interest rаte hаs а negаtive аnd significаnt effect on LQ45 index pаrtiаlly