Munk and Riley revisited: Nutrient diffusion transport and rates of phytoplankton growth

Although phytoplankton nutrient uptake rates are controlled primarily by biological properties of the organism and nutrient concentration, diffusion transport of nutrient to the organism through the medium in which the organism is immersed can influence uptake rates. The original ideas of Munk and Riley on control of nutrient uptake by diffusion transport are recast in terms of present knowledge of the interaction of diffusion transport and biological control of uptake rates...

Narrator’s Attitudes Toward Slavery in Oroonoko and Robinson Crusoe

Oroonoko by Aphra Behn and Robinson Crusoe by Daniel Defoe are narrated by speakers encountering enslaved people in South America during English imperialism. The narrators’ respective sentimental and practical voices are manifested through the details of their narratives: Behn’s speaker tends to dwell on romantic points, like Oroonoko’s relationship with his lover, while Crusoe favors pragmatic details, like the quantification of supplies. The narrators’ perspectives color their relationships with enslaved individuals. Behn’s narrator’s relationship with Oroonoko is filtered through her romantic lens, enabling a dynamic and communicative relationship with the Prince that exhibits her sympathy towards his enslavement. In contrast, Crusoe assesses Friday upon his usefulness and ease with which he can assimilate to his “Master’s” preferences, seeking to convert Friday to Christianity and constantly maintaining the native’s inferiority. While Behn’s narrator redeemed Oroonoko from slavery, her sentimentality does not extend to other slaves, revealing that both narrators accept the general practice of slavery with a practical outlook and harbor beliefs of racial hierarchies. Consequently, the narrators’ attitudes toward slavery indicate the limitations of human sympathy and highlight the social hierarchies underlying even the most sentimental perspectives

Toxic binding of cupric ion by marine phytoplankton

The data presented by Gavis et al. (1981, J. Mar. Res., 39, 315–333) for the specific growth rate of phytoplankton in nutrient replete medium as a function of cupric ion activity can be described quantitatively by equations that relate the equilibrium binding of cupric ions to a cell receptor site. Statistically significant conditional binding constants could be estimated from the data for at least eight clones among three species. One clone could bind only one cupric ion per site. The others could bind a maximum of two cupric ions per site. For one of these clones K1 \u3e K2. For the remaining six K2 \u3e K1. For three clones K2 was so much larger than K1, that only their product β2 could be determined. Values of K1 ranged between 8.6 × 108 and 5.7 x 1010, values of K2 ranged between 3.1 x 108 and 1.9 × 1010, while those of β2 ranged between 3.5 × 1018 and 3.8 × 1020

Drowning in Desire

Despite being called a “love song,” T.S. Eliot’s “The Love Song of J. Alfred Prufrock” is characterized by seemingly chaotic form that contrasts with a typical romance. Intentional irregularities in form express Prufrock’s overwhelming desire for companionship and his troubled self-consciousness. Through close readings of Eliot’s odd use of pronouns, rhyme scheme, and ellipses, Prufrock’s unsatiated desire and resulting inner instability are manifested. The undefined “you” and “I” demonstrate the tension between Prufrock’s public and private masks, which he creates to entice women. This romantic endeavor results in unharmonized versions of himself that wrestle with playfulness and agitation at his isolation. The tension between his selves disrupts the passage of time in Prufrock’s monologue, shown through ellipses and intentional blank space. Though he creates the masks to satisfy his desire, Prufrock loses control over his self-consciousness and endures a limbo of longing. Eliot’s irregular form appears anarchic but mimics Prufrock’s erratic consciousness, compromised by desire. The “love song” may conclude with continued isolation and a broken self, but is poignant in its eternal desire

Pattern Formation: Gurken meets torpedo for the first time

AbstractIntercellular communication between oocyte and follicle cells, mediated by the gurken–torpedo/DER signalling pathway, has a crucial role in determining both anterior–posterior and dorsal–ventral polarity in Drosophila

Dissertation Rumination

The email read, “…as you all know, Leslie is planning to retire at the end of the academic year.” My eyes stopped at the end of that sentence. Retire? I didn’t know she was planning to retire. I immediately began to worry. How could Leslie retire? What about conference . presentations, data collection, Sociolinguistics class? Then I thought about it for another minute and started to smile. “Yeah,” I sighed, “I guess I can imagine it.” Leslie peering through binoculars at birds, hiking with Bruce in national parks, and delving into Native American arts. Good-bye staff meetings, deadlines, paperwork, committees, and email. In my mind’s eye, however, I see the door to Room 317 slam shut, and in the darkness, I start to reminisce about the many years I spent in that office as a student, assistant, and in the end, a friend

The translational repressors Nanos and Pumilio have divergent effects on presynaptic terminal growth and postsynaptic glutamate receptor subunit composition

Pumilio (Pum) is a translational repressor that binds selectively to target mRNAs and recruits Nanos (Nos) as a corepressor. In the larval neuromuscular system, Pum represses expression of the translation factor eIF-4E and the glutamate receptor subunit GluRIIA. Here, we show that Nos, like Pum, is expressed at the neuromuscular junction (NMJ) and in neuronal cell bodies. Surprisingly, however, Nos and Pum have divergent functions on both the presynaptic and postsynaptic sides of the NMJ. In nos mutant and nos RNA interference larvae, the number of NMJ boutons is increased, whereas loss of Pum reduces the bouton number. On the postsynaptic side, Nos acts in opposition to Pum in regulating the subunit composition of the glutamate receptor. NMJ active zones are associated with GluRIIA- and GluRIIB-containing receptor clusters. Loss of Nos causes downregulation of GluRIIA and increases the levels of GluRIIB. Consistent with this finding, the electrophysiological properties of NMJs lacking postsynaptic Nos suggest that they use primarily GluRIIB-containing receptors. Nos can regulate GluRIIB in the absence of GluRIIA, suggesting that the effects of Nos on GluRIIB levels are at least partially independent of synaptic competition between GluRIIA and GluRIIB. Nos is a target for Pum repression, and Pum binds selectively to the 3' untranslated regions of the nos and GluRIIA mRNAs. Our results suggest a model in which regulatory interplay among Pum, Nos, GluRIIA, and GluRIIB could cause a small change in Pum activity to be amplified into a large shift in the balance between GluRIIA and GluRIIB synapses