What's the difference between asterism and asteroid?

Asterism


Definition:

  • (n.) A constellation.
  • (n.) A small cluster of stars.
  • (n.) An asterisk, or mark of reference.
  • (n.) Three asterisks placed in this manner, /, to direct attention to a particular passage.
  • (n.) An optical property of some crystals which exhibit a star-shaped by reflected light, as star sapphire, or by transmitted light, as some mica.

Example Sentences:

  • (1) Microscopic examinations of eggs stained with aceto-orcein or the DNA fluorochrome bisbenzimide and direct observations on isolated sperm aster complexes show that halothane induces polyspermy (multiple sperm entry) when present at fertilization.
  • (2) Second, the bulk of the vegetally located myoplasm moves with the sperm aster towards the future posterior pole, but interestingly about 20% remains behind at the anterior side of the embryo.
  • (3) The CTR2611 antigen is present in the center of each of these asters.
  • (4) Cytoplasmic asters were observed at all doses tested.
  • (5) RNase alters the in vitro assembly of spindle asters in homogenates of meiotically dividing surf clam (Spisula solidissima) oocytes.
  • (6) ASTER is an integration of the ACQUIRE (AQUatic toxicity Information REtrieval system) and QSAR (Quantitative Structure Activity Relationships) systems.
  • (7) The data indicate that meiotic spindle assembly is dependent on ongoing protein synthesis in the cumulus-enclosed hamster oocyte; in contrast, chromatin condensation and aster formation are not as sensitive to protein synthesis inhibitors during meiotic resumption.
  • (8) The eggs of the surf clam Spisula solidissima were artificially activated, homogenized at various times in cold 0.5 M MES buffer, 1mM EGTA at pH 6.5, and microtubule polymerization was induced by raising the temperature to 28 degrees C. In homogenates of unactivated eggs few microtubules form and no asters are observed.
  • (9) 101:289-316) used computer simulations to show that long-range signals from the asters, varying inversely as various powers of distance, produce summed effects that are minima at the equator of spherical cells.
  • (10) Microinjection of SPN-3 antibody into taxol-treated mitotic PtK2 cells causes disruption of the asters as judged by tubulin staining of the same cells.
  • (11) Furthermore, numerous cytoplasmic asters become visible in the cytoplasm.
  • (12) This is accompanied by the apparent shortening of the microtubules running between the asters.
  • (13) Mesomere-mesomeres (which divide equally) and macromere-micromeres (which divide unequally) are compared in terms of their asters (both mitotic and so-called interphase asters), spindle apparatus, and contractile ring.
  • (14) Within 15 min after incubation in D2O, numerous fine centrosomal foci are detected, and they organize a connected network of numerous asters which fill the entire egg.
  • (15) In the normal two-celled embryos of various pulmonate molluscs, the orientation of spindles characteristic of metaanaphase is being frequently established gradually, in the process of transition from pro- to metaphase accompained by the growth of spindle and asters.
  • (16) Colcemid-treated prometaphase cells lysed into polymerization-competent tubulin develop large asters in the region of the centrioles and short tubules at kinetochores, making it unlikely that all microtubule formation in lysed cell preparations is dependent on tubulin addition to short tubule fragments.
  • (17) They located in euchromatin regions of thymus lymphocytes, with a characteristic aster-like immunofluorescence pattern, and on the border of condensed chromatin areas by deposition of immunogold particles in ultrathin sections of thymus.
  • (18) We conclude first, that centrioles contain RNA which is required for initiation of aster formation, and second, that the centriole activity or ability to assemble a mitotic aster is separable from the basal body activity, or ability to serve directly as a template for microtubule growth.
  • (19) When injected into fertilized eggs at streak stage, the tubulin was quickly incorporated into each central region of growing asters.
  • (20) The asters then divide to form a transient tetrapolar figure.

Asteroid


Definition:

  • (n.) A starlike body; esp. one of the numerous small planets whose orbits lie between those of Mars and Jupiter; -- called also planetoids and minor planets.

Example Sentences:

  • (1) Lipase from Geotrichum asteroides appears more resistant to high temperatures and pH changes than the enzyme from Penicillium sp.
  • (2) This strain of the organism fits a pattern of susceptibility that is rare among N asteroides isolates in general and has been called the type 5 pattern, described as a resistance to broad spectrum cephalosporins, ciprofloxacin, and all aminoglycosides except amikacin.
  • (3) Within 18-24 h asteroid bodies consisting of an amorphous centre with fine radiating needle crystals were seen.
  • (4) The study deals with the phagocytosis of Nocardia asteroides (strain Weipheld) and the subsequent intracellular proliferation in peritoneal macrophage cells.
  • (5) Chalky white colonies, 0.5 to 1.0 mm in diameter, that were subsequently identified as N. asteroides grew well on the BCYE media.
  • (6) This must be regarded as an antigen-antibody precipitate corresponding to the "asteroid body" of previous authors.
  • (7) All six N. brasiliensis and six N. otitidis-caviarum were susceptible to gentamicin and minocycline, while all 15 N. asteroides were not.
  • (8) Microtubules and centrioles were not found in asteroid bodies, although a centriolar field was present in 1 giant cell close to the plasma membrane, completely unrelated to the asteroid body.
  • (9) Complications are unusual, but of the ones that do occur, infection, particularly with Nocardia asteroides, and fibrosis are the most common.
  • (10) The somewhat fortuitous isolation of Nocardia asteroides and its significance are discussed.
  • (11) The pathogenicity of Nocardia asteroides and other strains of different Nocardia species against chicken embryos was investigated.
  • (12) An acute suppurative abscess characterizes the lesions of N. asteroides.
  • (13) The inner solar system is filled with dust between the planets, called the zodiacal cloud, which starts out at the asteroid belt and slowly drifts towards the sun.
  • (14) Ominously, researchers have already discovered that there must be ten times as many potentially dangerous asteroids out there with sizes of the order of tens of metres as previously thought.
  • (15) With N. asteroides, the direct plating method gave equivocal results.
  • (16) The organism identified as Nocardia asteroides resisted to sulfonamide and cotrimoxazole but sensitive to chloramphenicaol and streptomycin in vitro.
  • (17) These findings and clinical observations suggest that inhibition of N. asteroides by neutrophils may be important in vivo.
  • (18) Evidence for the possible developmental pathway of the Schaumann body is provided by morphological changes within myelinoid figures intimately related to the asteroid body.
  • (19) Two and one half years later N. asteroides pneumonia recurred and resulted in death from respiratory failure.
  • (20) The official citation for the asteroid reads: "Iain M. Banks (1954-2013) was a Scottish writer best known for the Culture series of science fiction novels; he also wrote fiction as Iain Banks.