Apioceridae (Insecta: Diptera): cladistic reappraisal and biogeography

Twenty members of the fly families Apioceridae and Mydidae are compared in terms of 77 adult characters. Cladistic analysis of 91 synapomorphies provides a well corroborated reconstruction of lineage relationships, and reveals that the Apioceridae is paraphyletic with respect to the Mydidae. In order to render the Apioceridae monophyletic, the genus Rhaphiomidas and the subfamily Megascelinae of the Apioceridae are transferred to the Mydidae. The subfamily Rhaphiomidinae is reinstated to accommodate Rhaphiomidas , comprising the most plesiomorphic mydids. The relationships of the remaining subfamilies of Mydidae are discussed in the context of these findings. The genus Apiocera is divided into four subgenera, the type subgenus Apiocera Westwood in Australia, Pyrocera subgen. nov. in North America, and the subgenera Ripidosyrma Hermann and Anypenus Philippi are applied to the South African and South American species, respectively. A key to the four subgenera of Apiocera is provided. The biogeographic relationships of the subgenera and genera of the Apioceridae and the Megascelinae are discussed. Although considered an example of a transantarctic or Gondwanan group, we argue that the distribution of the Apioceridae predates the Mesozoic supercontinent Gondwanaland and extends onto sections of Pangaea, and should be termed 'Pangaean'. The cladistic relationships between the genera of Apioceridae and Megascelinae are consistent with the geological vicariance of the fragments of Pangaea on which they now occur.     

关养密度和成年雄鼠填充物的气味对黄毛鼠(Rattus rattoides)的发育和性成熟的影响(英文)

黄毛鼠（Ｒａｔｔｕｓ ｒａｔｔｉｄｅｓ）在群居（４只／笼）时体重及性器官,如睾丸和附睾的增长都受到了极大的抑制;血清中睾酮含量的迅速上升以及成熟精子在附睾的曲细精管中出现的时间也比单独关养的晚。成年雄鼠的笼填充物的气味能够诱导幼年雄鼠体重,睾丸的总量和长度以及血清中睾酮的含量的增加。     

Taphonomic and paleoecologic implications of flow-induced forces on concavo-convex articulate brachiopods: an experimental approach

The Orientation of benthic marine organisms may be disturbed by flow-induced forces (i.e. drag and lift) caused by wave and current activity. Drag and lift are partly a function of organism size and shape. Consequently, morphology may affect stability (defined as resistance to reorientation, flipping, or entrainment) both during the life of an organism and after its death. An understanding of drag-and-lift effects is therefore essential to the interpretation of paleoecology and biostratinomic processes. An experimental method for quantifying the relative effects of flow-induced forces is described. These forces are measured during flume experiments using transducers and plaster replicas of fossils. As an illustration of the method's potential for taphonomic research, results from experiments investigating the effects of concavo-convex morphologies of articulate brachiopods are presented. Concave-up and convex-up orientations are commonly used to infer paleohydraulic conditions. Two geniculate brachiopods (Rafinesquina alternata and Leptaena richrnondensis) and three flattened forms (a second morphotype of Rafinesquina altemata, Strophodonta demissa , and Tropidoleptus carinatus) were tested in convex-up and concave-up postures and in three azimuthal orientations (hingeline oriented upstream, hingeline downstream, and hingeline parallel to flow). Concave-up orientations consistently exhibit higher drag than convex-up orientations, and this supports the common observation that valved fossils are typically found convex up in paleoenvironments dominated by traction transport. The presence of geniculation significantly increases drag. Lift is relatively insignificant for all models in most orientations. □ Taphonomy, paleoecology, brachiopods, flow-induced forces, transport.     

Resource limitation and the lethal and sublethal effects of a viral pathogen in the Indian meal moth, Plodia interpunctella

Abstract.

• 1 The effects of resource limitation and the lethal and sublethal effects of a granulosis virus on a lepidopteran host, the Indian meal moth, Plodia interpunctella, were examined.
• 2 The food quality was manipulated by the addition of an inert bulking agent (methyl cellulose) which caused the size, development rate and fecundity of the moths to be reduced.
• 3 The resource quality had no effect on the mortality due to the virus. In contrast, sublethal effects of the virus on pupal weight were more apparent under conditions of resource limitation.
• 4 Considerable variation between the sublethal effects after challenge with different doses of the virus was found. The balance between deleterious sublethal effects of the virus and the selection of more robust individuals by the bioassays is proposed as a mechanism to explain this variation.
• 5 Implications for the dynamics of insect hosts and their pathogens are discussed.

     

CHARACTERIZATION OF A BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS) KIDNEY EPITHELIAL CELL LINE

Abstract: An epithelial cell line, Carvan dolphin kidney (CDK), isolated from a prematurely born female bottlenose dolphin, Tursiops truncatus , exhibited growth characteristics not previously reported for cetacean cells in culture. CDK cells were cytokeratin positive and demonstrated a maximum doubling time of 1.31 days, with plating and colony forming efficiencies approaching 100% for the early population doublings. Despite an unusually efficient colony-forming ability and rapid growth, these cells were neither transformed nor immortal, displaying normal contact inhibition, anchorage dependence, and the requirement for high concentrations of fetal bovine serum in the growth medium. CDK cells exhibited age-dependent changes in growth rate, colony-forming efficiency, and cytoplasmic profile, and showed a finite lifespan of about 50 population doublings and a stable 2N = 44 karyotype which correlates with previously reported cytogenetic analyses. Velocity sedimentation analysis showed that CDK cells contained nuclear aryl hydrocarbon receptor (Ah), indicating their potential to be induced for cytochrome P450. These data suggest that CDK cells may have utility as an in vitro toxicological model for evaluating hydrocarbon contaminant effects on Tursiops truncatus , a protected marine mammal.     

Molecular Characterization of a Cytoplasmic Dynein from Dictyostelium

Cytoplasmic dynein is a high molecular weight, microtubule-based mechanochemical ATPase that is believed to provide motive force for a number of intracellular motilities, including transport of membrane-bound organelles. Cytoplasmic dynein also localizes to the mitotic spindles of some organisms and to the kinetochore regions of some condensed chromosomes, where it may play an active role in spindle assembly, spindle position, and/or chromosome movement during cell division. Despite active research efforts from a number of laboratories, little detail is yet available about dynein-based cellular activities. This paper describes our efforts to characterize cytoplasmic dynein from Dictyostelium and to use this protist as a molecular genetic factory to probe structure-function relationships of this molecule.     

Modulation of the Plasma Membrane Electron Transfer System in Root Cells of Limnobium stoloniferum by External pH

The influence of ferricyanide on transmembrane electron transfer,proton secretion, membrane potential, and cytoplasmic pH ofLimnobium stoloniferum (G.F. Mey) Griseb. root cells was investigatedat different external pH HCF III reduction by the roots was accompanied by membrane depolarization,an increase in proton secretion and by alkalinization of thecytoplasm. Change of membrane potential and cytoplasmic pH aswell as transmembrane e^– transfer was more pronouncedat acid external pH. The rate of proton flux was linearly dependenton the rate of electron transfer. The slope of the relationshipwas around 1, independent of external pH The data are in agreement with the hypothesis that electrontransfer at the plasma membrane is directly coupled to protonsecretion. It is suggested that both e^– and redox-coupledH⁺ transport are activated by acid external pH Key words: Plasmalemma redox system, electron transfer, proton transport, pH, membrane potential, Limnobium stoloniferum     

Common Epitopes In the Circumsporozoite Proteins of Plasmodium Berghei and Plasmodium Gallinaceum Identified By Monoclonal Antibodies to the P. Gallinaceum Circumsporozoite Protein

ABSTRACT. Monoclonal antibodies that react with the circumsporozoite protein of the avian malaria Plasmodium gallinaceum sporozoites also reacted with circumsporozoite protein of the rodent malaria Plasmodium berghei. Two types of reactivity were identified: 1) two monoclonal antibodies reacted with P. berghei sporozoite protein by enzyme-linked immunosorbent assay, Western blot and indirect immunofluorescence antibody, 2) six other monoclonal antibodies reacted with P. berghei sporozoites by ELISA and Western blot only. We studied whether these differences could be explained by reactivity in enzyme-linked immunosorbent assay with different P. berghei circumsporozoite peptides. Although all P. gallinaceum monoclonal antibodies reacted with the P. berghei repeats, the first group reacted with a conserved peptide sequence, N1, whereas the second group did not. These results suggest that circumsporozoite proteins from P. gallinaceum and P. berghei share common epitopes. the biological significance of our finding is not yet clear. Indeed, the cross-reactive monoclonal antibodies giving a positive indirect immunofluorescence antibody with the P. berghei sporozoites only caused a borderline effect on the living P. berghei parasites in vitro as measured by inhibition of sporozoite infectivity.     

Microstructure and affinity of the enigmatic Devonian tubular fossil Trypanopora

The adult shell (teleoconch) of the enigmatic tubular Givetian fossil Trypanopora is comprised of two principal layers: an outer fibrous prismatic layer and an inner micro-lamellar (irregular cross-bladed) layer, with local, closely-spaced disruptive punctation. The fine preservation suggests an original calcite composition. The shell microstructure shows great similarities with that of both vermiform 'gastropods' and tentaculitoids, suggesting a close affinity between Trypanopora and these groups. The septa have an irregular micro-lamellar (cross-bladed) microstructure in continuity with the inner wall, and a morphology unlike that of any known mollusc. The class Tentaculitoidea is emended to include two new orders: Microconchida for the vermiform 'gastropods' and Trypanoporida for Trypanopora and allied genera. □ T rypanopora , microstructure, protoconch, teleoconch, fibrous prismatic layer, micro-lamellar layer, tubulation, septation, vermiform 'gastropods', Tentaculitoidea, Microconchida, Trypanoporida.     

Species-specific growth responses of favositid corals to soft-bottom substrates

Gibson, Michael A. & Broadhead, Thomas W. 1989 07 15: Species-specific growth responses of favositid corals to soft-bottom substrates. Lethaia , Vol. 22, pp. 287–299. Oslo. ISSN 0024–1164.
Species of favositid corals from the Upper Silurian and Lower Devonian of Tennessee, USA, exhibit structural modifications related to corallum geometry, interfacial skeletal material, and biotic associations that enabled them to survive in terrigenous mud rich environments. Favosites conicus Hall (Lower Devonian) had a flat, holotheca-covered base and a radial pattern of colony growth, but apparently had a short life span and may not have survived beyond the first reproductive cycle (monocarpous). It was adapted for living between major episodes of terrigenous mud influx. F. foerstei (Lower Devonian) had a convex, pseudoholotheca-covered base and a modified axial pattern of colony growth. Its large size, in comparison to that of F. conicus , suggests a longer lived colony (polycarpous), in which continued upward and outward growth enabled it to survive episodic sediment influx. F. forbesi (Upper Silurian) exhibited radial growth to form either (1) a globose corallum that was symbiotic with the stalks of living crinoids permitting the colony to live entirely above the substrate, or (2) a Gorallum with a steeply convex, holotheca-covered base that represents a bottom-dwelling colony in which the rate of growth probably only slightly exceeded the rate of sediment accumulation. * Functional morphology, astogeny, paleoecology, Tabulata .