34 results match your criteria: "Pasadena City College[Affiliation]"

Living rain gauges: cumulative precipitation explains the emergence schedules of California protoperiodical cicadas.

Ecology

October 2017

Natural Sciences Division, Pasadena City College, 1570 East Colorado Boulevard, Pasadena, California, 91106, USA.

Mass multi-species cicada emergences (broods) occur in California with variable periodicity. Here we present the first rule set that predicts the emergence of protoperiodical cicada communities. We tested two hypotheses with a dataset consisting of direct observations and georeferenced museum specimen records: first, that cicada broods are triggered to emerge by periodic ENSO events and second, that brood emergences occur after precipitation accumulates above a threshold value.

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A new species of Megatibicen endemic to Mescalero-Monahans shinnery sands (Hemiptera: : Cicadidae).

Zootaxa

February 2017

Natural Sciences Division, Pasadena City College, 1570 East Colorado Boulevard, Pasadena, CA 91106 Research Associate, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007..

Megatibicen harenosus sp. n. is described from the Mescalero-Monahans shinnery sands of New Mexico and Texas, U.

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In a dispersal-limited species that has evolved reproductive character displacement at a contact zone, a cline in mating behaviour may result if gene flow diffuses alleles out of the contact zone into allopatric populations. Prior work has found such a clinal pattern in the shield-back katydid Aglaothorax morsei, in which the male calling songs in a sympatric population have a displaced, short interpulse interval that increases in length with increasing distance from the contact zone. In this study, molecular phylogenetic and female preference data show that (1) sympatric populations result from secondary contact, (2) hybridization in sympatry has resulted in unidirectional mitochondrial introgression and (3) female preferences are consistent with reproductive character displacement and could generate a cline in mating behaviour.

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Targeted Type 2 Alveolar Cell Depletion. A Dynamic Functional Model for Lung Injury Repair.

Am J Respir Cell Mol Biol

March 2016

1 Developmental Biology and Regenerative Medicine Program, Department of Surgery, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; and.

Type 2 alveolar epithelial cells (AEC2) are regarded as the progenitor population of the alveolus responsible for injury repair and homeostatic maintenance. Depletion of this population is hypothesized to underlie various lung pathologies. Current models of lung injury rely on either uncontrolled, nonspecific destruction of alveolar epithelia or on targeted, nontitratable levels of fixed AEC2 ablation.

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RE1-Silencing Transcription factor (REST) has a well-established role in regulating transcription of genes important for neuronal development. Its role in cancer, though significant, is less well understood. We show that REST downregulation in weakly invasive MCF-7 breast cancer cells converts them to a more invasive phenotype, while REST overexpression in highly invasive MDA-MB-231 cells suppresses invasiveness.

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IBI series winner. Exploring the evolution of human mate preference.

Science

November 2013

Natural Sciences Division, Pasadena City College, 1570 East Colorado Boulevard, Pasadena, CA 91106, USA.

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Over the last decade neuroscientists have accumulated a wealth of information confirming the trophic effects of 17beta-estradiol (E2) on a variety of brain regions, such as the effects on hippocampal spine density, as well as other measures of structural reorganization. Here, we explore the hypothesis that E2 exerts a positive trophic effect on the cholinergic neurons of the basal forebrain, an area heavily implicated in memory and attentional processes. Female rats were ovariectomized at 3 months of age and lesioned with the immunotoxin 192 IgG-saporin before receiving a subcutaneous pellet containing .

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A possible role of glutamate in the aging process.

Med Hypotheses

April 1994

Pasadena City College, Life Sciences Department, California 91106-2003.

Glutamate (Glu) is considered here for its possible role as a naturally occurring mammalian 'age inducing' substance. The existence of 'Glu elicited headaches', may serve as an indication that Glu could negatively affect the human adult CNS. The prevalence of Glu induced headaches was found to be 28.

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