Molecular phylogeny of the fungus gnat subfamilies Gnoristinae and Mycomyinae,and their position within Mycetophilidae (Diptera)

The phylogeny of the fungus gnat family Mycetophilidae (Diptera) is reconstructed with a focus on the species‐rich and taxonomically difficult subfamilies Gnoristinae and Mycomyinae. The multigene phylogenetic analyses are based on five nuclear (18S, 28S, CAD, MCS, ITS2) and four mitochondrial (12S, 16S, COI, CytB) gene markers. The analyses strongly support the monophyly of Mycetophilidae and the subfamilies Manotinae, Sciophilinae, Leiinae, and Mycomyinae, although Gnoristinae is paraphyletic with respect to Mycetophilinae. All the genera and groups of genera included are supported as monophyletic, except for Acomoptera Vockeroth, Boletina Staeger, Dziedzickia Johannsen, Ectrepesthoneura Enderlein, and Neoempheria Osten Sacken. Ancestral character state reconstructions were applied to two morphological features present in Gnoristinae and Mycomyinae (i.e. presence of setae on wing membrane and wing vein R₄) in order to assess their evolution. The wing vein R₄ appears as an unstable character, spread throughout different clades. A dated phylogeny of the family Mycetophilidae showed that most of the subfamilies of Mycetophilidae originated and diversified during the Cretaceous. The youngest subfamilies, originated in the Paleogene, appear to be Mycomyinae and Mycetophilinae.     

Further results on the survival of a gene represented in a founder population

This paper is concerned with gene survival in a population which may increase without density dependence according to a generalization of the Moran model for haploid individuals. A selective advantage to one allele and the possibility of differential reproductive rates are allowed. Simple conditions are given for ultimate homozygosity to be certain and for the possibility of ultimate polymorphism. The results complement and extend those of Heyde (1981, 1982).     

FEM-based oxygen consumption and cell viability models for avascular pancreatic islets

Background  

The function and viability of cultured, transplanted, or encapsulated pancreatic islets is often limited by hypoxia because these islets have lost their vasculature during the isolation process and have to rely on gradient-driven passive diffusion, which cannot provide adequate oxygen transport. Pancreatic islets (islets of Langerhans) are particularly susceptible due to their relatively large size, large metabolic demand, and increased sensitivity to hypoxia. Here, finite element method (FEM) based multiphysics models are explored to describe oxygen transport and cell viability in avascular islets both in static and in moving culture media.     

Carbonic anhydrase activity in the blood of adult sheep, fetal sheep and lambs

The activity of carbonic anhydrase (E.C.4.2.1.1) (CA) has been measured in the blood of adult and fetal sheep and lambs. The mean activity in adult sheep was 0.89 enzyme units (EU) per 100 micrograms of Hb. The activity in fetal sheep aged 90 days was just below 20% of this and in fetuses near full term was just under 40% of the mean adult level. The regression line gave an increase of CA activity (per 100 micrograms Hb) of 0.004 EU/day. The appearance of CA in fetal blood normally occurred before any detectable production of adult Hb. One aberrant fetus showed early development of the adult pattern in the red cells, having adult type Hb and adult levels of CA during the period of 116-128 days of fetal age. In the period after birth the CA level in the blood rose rapidly, reaching the adult level 30 days after birth. During this period activity per 100 micrograms HB increased by 0.014 EU/day, significantly faster than during fetal life.