Eurycea nana

Number of Pages: 2Integrative BiologyGeological Science

Comparing and contrasting development and reproductive strategies in the pupal hyperparasitoids Lysibia nana and Gelis agilis (Hymenoptera: Ichneumonidae)

In most animals, the optimal phenotype is determined by trade-offs in life-history traits. Here, I compare development and reproductive strategies in two species of solitary secondary hyperparasitoids, Lysibia nana and Gelis agilis, attacking pre-pupae of their primary parasitoid host, Cotesia glomerata. Parasitoid larvae of both species exploit a given amount of host resources with similar efficiency. However, adults exhibit quite different reproductive strategies. Both species are synovigenic, and female wasps emerge with no mature eggs. However, G. agilis must first host-feed to produce eggs, while L. nana does not host-feed but mobilizes internal resources carried over from larval feeding to initiate oogenesis. Further, G. agilis is wingless, produces large eggs, has a long life-span, and generates only small numbers of progeny per day, whereas these traits are reversed in L. nana. Given unlimited hosts, the fecundity curve in L. nana was “front-loaded,” whereas in G. agilis it was depressed and extended over much of adult life. In L. nana (but not G. agilis), wasps provided with honey but no hosts lived significantly longer than wasps provided with both honey and hosts. Differences in the fecundity curves of the two hyperparasitoids are probably based on differing costs of reproduction between them, with the wingless G. agilis much more constrained in finding hosts than the winged L. nana. Importantly, L. nana is known to be a specialist hyperparasitoid of gregarious Cotesia species that pupate in exposed locations on the food plant, whereas Gelis sp. attack and develop in divergent hosts such as parasitoid cocoons, moth pupae and spider egg sacs. Consequently, there is a strong match between brood size in C. glomerata and egg production in L. nana, but a mismatch between these parameters in G. agilis.

Anti-pornography

One striking feature of pornographic images is that they emphasize what is depicted and underplay the way it is depicted: the experience of pornography rarely involves awareness of the picture’s composition or of visual rhyme. There are various ways of making this distinction between what is depicted in a picture and the way the depicted object is depicted in it. Following Richard Wollheim, I call these two aspects, the ‘what’ and ‘how’ of pictorial representation ‘recognitional’ and ‘configurational’, respectively. Some pictures emphasize one of these aspects while underplaying the other. Pornographic pictures try to trigger as little attention to the ‘configurational’ aspect as possible. Instead of examining pornography, where the ‘configurational’ aspect of experience is underplayed, I focus on a historical attempt to create images of the female body where the ‘recognigional’ element is the one that is underplayed and the ‘configurational’ elements of the picture form an essential part of our experience. The pictures I have in mind are André Kertész’s series of photographs from 1933, called Distortions. I argue that Kertész’s Distortions are in this respect the counterpoint of pornography: they may be the least pornographic representations of the female nude. Instead of ignoring the ‘configurational aspects of the picture, making the picture transparent and fully at the service of showing the female body and thus to trigger arousal, Kertész aims to achieve the exact opposite. His photographs strip the female body of all its sexual connotations and draw our attention to the formal features of the picture – which is quite a feat in the light of the subject matter of these pictures that normally draw our attention away from the formal features of pictures

Shareholder Employment at Red Dog Mine

Under the Alaska Native Claims Settlement Act of 1971, Iñupiat of northwest Alaska organized as shareholders in the NANA1 Regional Corporation, Inc., and received title to 2,258,836 acres, including rights to the rich Red Dog zinc deposit. In 1982, NANA signed a joint-venture agreement with Teck2 to develop the mine, including provisions for preferential hire for qualified NANA shareholders. The agreement aimed for 100% shareholder hire by 2001. As of 2010, Teck had 220 NANA shareholders in full-time employment, which is 53 percent of the workforce. Other mines around the world have similar indigenous or local hire agreements with mixed success. The Voisey’s Bay mine sets the high mark for Canada with an Aboriginal hire rate of 54 percent (AETG 2008), followed by Ekati diamond mine at 50 percent (BHP Billiton 2011). So the track record for indigenous employment at Red Dog is high by global standards, although it falls short of NANA and Teck’s goal. What are the continuing barriers to increasing shareholder hire, retention and promotion

In vitro and in vivo modification of Neisseria gonorrhoeae lipooligosaccharide epitope structure by sialylation.

After growth of gonococci in the presence of cytidine monophospho-N-acetyl-neuraminic acid (CMP-NANA), their 4.5-kD lipooligosaccharide (LOS) component was increased by approximately 400 daltons, whereas the LOS of strains lacking the 4.5-kD component were unaffected. Expression of mAb-defined epitopes on the 4.5-kD component was decreased on LOS of strains grown in CMP-NANA, and treatment of the LOS with neuraminidase reversed this affect. Gonococci incubated with human PMNs also had decreased expression of the 4.5-kD+ epitopes. A detergent extract of gonococci incorporated radiolabeled NANA in the LOS, suggesting the presence of a sialyltransferase in gonococci. Exogenous sialyltransferases also could use LOS as an acceptor

Reliability and Precision of the Nana Protocol to Assess Body Composition Using Dual Energy X-ray Absorptiometry

The Nana positioning protocol is widely used to position participants to minimize technical error when undertaking body composition scanning and analysis with a Dual energy X-Ray absorptiometry (DXA) machine. Once biological and technical errors are accounted for, the only variation in test–retest results is from statistical fluctuation or machine error. Therefore, the aim of this study is to assess the test–retest reliability of the Nana positioning protocol and establish the smallest real difference percentage (SRD%). A gender-balanced group of 30 participants (15 males, 15 females) underwent two scans in succession using the Nana positioning protocol, with repositioning between scans. Percentage change in mean with typical error, Intraclass Correlation Coefficients (ICC), and standard error measurement percentage (SEM%) were used to identify the test–retest reliability and error rate of these protocols. Additionally, SRD% was calculated to assess the point at which clinically important changes occurred in a participant. The reliabilities of the whole body and regional scans were excellent. Percentage change in mean ranged between 0.00% and 0.23%. High reproducibility of the Nana positioning protocol was evident through an ICC ranging between 0.966–1.000. Additionally, typical error, SEM%, and SRD% were all low. Interestingly, fat mass was associated with the largest fluctuations observed to be associated with any of the parameters assessed. When all sources of biological and technical errors have been accounted for, the Nana positioning protocol has excellent test–retest reliability and produces low SEM% and SRD%

Dialogue-based teaching: The art museum as a learning space

Book review of "Olga Dysthe, Nana Bernhardt & Line Esbjørn (2013). Dialogue-based teaching. The art museum as a learning space. Copenhagen, Denmark: Skoletjenesten.

Structural characterization of the carbohydrate-binding module of NanA sialidase, a pneumococcal virulence factor

This research was supported by the University of St Andrews and grants provided by the Medical Research Council.Background: Streptococcus pneumoniae Neuraminidase A (NanA) is a multi-domain protein anchored to the bacterial surface. Upstream of the catalytic domain of NanA is a domain that conforms to the sialic acid-recognising CBM40 family of the CAZY (carbohydrate-active enzymes) database. This domain has been identified to play a critical role in allowing the bacterium to promote adhesion and invasion of human brain microvascular endothelial cells, and hence may play a key role in promoting bacterial meningitis. In addition, the CBM40 domain has also been reported to activate host chemokines and neutrophil recruitment during infection. Results: Crystal structures of both apo- and holo- forms of the NanA CBM40 domain (residues 121 to 305), have been determined to 1.8 angstrom resolution. The domain shares the fold of other CBM40 domains that are associated with sialidases. When in complex with alpha 2,3- or alpha 2,6-sialyllactose, the domain is shown to interact only with the terminal sialic acid. Significantly, a deep acidic pocket adjacent to the sialic acid-binding site is identified, which is occupied by a lysine from a symmetry-related molecule in the crystal. This pocket is adjacent to a region that is predicted to be involved in protein-protein interactions. Conclusions: The structural data provide the details of linkage-independent sialyllactose binding by NanA CBM40 and reveal striking surface features that may hold the key to recognition of binding partners on the host cell surface. The structure also suggests that small molecules or sialic acid analogues could be developed to fill the acidic pocket and hence provide a new therapeutic avenue against meningitis caused by S. pneumoniae.Publisher PDFPeer reviewe