An update on the middle levels problem

The middle levels problem is to find a Hamilton cycle in the middle levels, M_{2k+1}, of the Hasse diagram of B_{2k+1} (the partially ordered set of subsets of a 2k+1-element set ordered by inclusion). Previously, the best result was that M_{2k+1} is Hamiltonian for all positive k through k=15. In this note we announce that M_{33} and M_{35} have Hamilton cycles. The result was achieved by an algorithmic improvement that made it possible to find a Hamilton path in a reduced graph of complementary necklace pairs having 129,644,790 vertices, using a 64-bit personal computer.Comment: 11 pages, 5 figure

Survey for Etomopathogenic Nematodes and Entomopathogenic Fungi in Alfalfa Snout Beetle, \u3ci\u3eOtiorhynchus Ligustici\u3c/i\u3e (L.) (Coleoptera: Curculionidae), Infested Fields in Hungary and in New York State

A survey for etomopathogenic nematodes and fungi in alfalfa snout beetle Otiorhynchus ligustici (L.) infested fields was conducted in Hungary, where this beetle is native, and in New York State, where the alfalfa snout beetle is an invasive species. Soil samples were collected in Hungary and in New York in alfalfa snout beetle infested alfalfa fields in spring 2002. Galleria mellonella (L.) larvae were used as bait insects. The entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae were found in Hungary and New York. The frequency of plots with entomopathogenic fungi was not significantly different between locations in Hungary and New York. The entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis sp. were found in Hungary and New York and S. feltiae was only found in Hungary. The frequency of plots with entomopathogenic nematodes was not significantly different between locations in Hungary and New York. S. carpocapsae and S. feltiae were found in coexistence at one location in Hungary

Field Persistence of \u3ci\u3eSteinernema Carpocapsa\u3c/i\u3e Weiser (Ny001), \u3ci\u3eSteinernema Feltiae\u3c/i\u3e Filipjev (Valko) and \u3ci\u3eHeterorhabditis Bacteriophora\u3c/i\u3e Poinar (Oswego) in Alfalfa Fields

The long term field persistence of Steinernema carpocapsae Weiser, strain NY001, S. feltiae Filipjev, strain Valko and Heterorhabditis bacteriophora Poinar, strain Oswego was investigated in an alfalfa field infested by the alfalfa snout beetle, Otiorhynchus ligustici L. Nematodes were applied in single-species, two-species and three-species combinations at a total of 2.5 × 109 infective juveniles per hectare. Soil samples were taken approximately every two weeks from mid/late May to late October in 2004 and 2005. Two soil samplings were conducted in 2006 at the end of May and in early July. All nematodes persisted in the field at the time of the last sampling in July 2006, over two years after application suggesting long term persistence of these nematodes and the potential to coexist in combinations. Steinernema feltiae Valko was not detected in the three-species combination after June 8, 2005, approximately one year after nematode application suggesting that S. feltiae Valko cannot compete effectively when a specialized ambusher nematode (S. carpocapsae NY001) and a specialized cruiser nematode (H. bacteriophora Oswego) are present simultaneously. In 2006, two years after nematode application, a marked movement of nematodes into experimental plots where they were not applied was observed. S. carpocapsae NY001 was found in the highest number of plots where it wasn’t applied. Given the ambusher behavior of S. carpocapsae NY001, it is suspected that its movement occurred via infected, but still live adult alfalfa snout beetles

Troubling the “WE” in art education: Slam poetry as subversive duoethnography

Scholarly dialogues are filled with discussions of teacher’s personal perspectives, experiences, and challenges - but rarely do these dialogues include the narratives that lie beneath the surface. The subversive tales confronting stories of microagressions, alternate histories, and institutionalized norms that shape the educational landscape we navigate daily. This paper is focused on bringing to the surface a call and response lament of two social justice-oriented art educators--one Black, the other White. Using the dialogic methodology of duoethnography and the performative aspects of slam poetry, we share our racialized-teaching accounts as a multisensory experience, where text and performative orality share a chimeric relationship. The slam poem format, along with a critical arts-based perspective, allows us to speak/perform with urgency alongside one another to share tales of an educational landscape rife with racialized inequities. Using the metaphor of eyesight, and its subsequent limitations, our poem references the challenges of human interaction within the rubric of racial categorization. We see slam poetry as a democratic means of performing identity and as a way to subvert the limitations of traditional hegemonic forms and norms and frame our poetic call and response as verses from below. This form of poetic lament frames our socio-political interaction around the concepts of Whiteness and Blackness in and through teaching and learning in art education. We close with brief considerations for how this approach might be generative in critically framing personal and educational interactions between/among/across difference

Comparative Study of \u3ci\u3eMecinus Janthiniformis\u3c/i\u3e (Coleoptera: Curculionidae) Attack and Simulated Mowing for Control of \u3ci\u3eLinaria Dalmatica\u3c/i\u3e Spp. \u3ci\u3eDalmatica\u3c/i\u3e (Plantaginaceae)

Dalmatian toadflax, Linaria dalmatica spp. dalmatica (L.) Mill. (Plantaginaceae) has invaded over one million hectares in the western United States and Canada, in habitats similar to its native range. Two field studies were conducted to examine the impact of simulated mowing or insect herbivory on L. dalmatica growth and reproduction. Simulated mowing over the duration of the study decreased L. dalmatica total biomass per square meter, significantly reduced the total number of fruits and flowers per square meter, and resulted in significantly shorter flowering stems in the simulated mowing plots than in their controls. Plants in plots attacked by Mecinus janthiniformis Toševski and Caldara (Coleoptera: Curculionidae) had significantly less biomass per square meter, significantly fewer total numbers of fruits and flowers per square meter, and significantly fewer reproductive structures per stem than plants in paired control plots over the duration of the study. Specifically, both management tactics resulted in a negative impact on this invasive plant. With repeated tissue removal or damage, a reduction in numbers of fruits and flowers per stem on both the stems subjected to simulated mowing and Mecinus-attacked stems relative to their controls suggests that long term stress effects on the plants may be similar. The results of these studies suggest that mowing may warrant further evaluation as a possible method of control in areas where M. janthiniformis release is not effective

Comment on 'Secure Communication using mesoscopic coherent states', Barbosa et al, Phys Rev Lett 90, 227901 (2003)

In a recent letter, Barbosa et al [PRL 90, 227901(2003)] claim that secure communication is possible with bright coherent pulses, by using quantum noise to hide the data from an eavesdropper. We show here that the secrecy in the scheme of Barbosa et al is unrelated to quantum noise, but rather derives from the secret key that sender and receiver share beforehand

Reply to "Comment on `Resilience of gated avalanche photodiodes against bright illumination attacks in quantum cryptography'"

This is a Reply to the Comment by Lydersen et al. [arXiv: 1106.3756v1]

The spectral energy distribution of NGC 1275

An analysis of absolute spectral energy distributions of interstellar gas for a galaxy (NGC 1275) is presented. Infrared spectra data shows heavy reddening. It is proposed that the interstellar gas may be ionized by shock waves or by nonthermal or stellar radiation. It is suggested, that high velocity, emission-line knots are H2 regions in a Perseus cluster galaxy or intergalactic gas cloud seen in projection against NGC 1275

Alfalfa Snout Beetle, \u3ci\u3eOtiorhynchus Ligustici\u3c/i\u3e L. (Coleoptera: Curculionidae): Methods for Egg Collection and Larval Rearing

The alfalfa snout beetle, Otiorhynchus ligustici L., is the most serious pest of alfalfa in northern New York State. Recent research efforts focused on the biological control of this insect require the availability of all life stages. With a 2-year lifecycle and a mandatory diapause, the artificial rearing of a laboratory culture appears to be a non-viable option at present, but methods described here can be used to obtain sufficient numbers of eggs and larvae over an extended period of time for research purposes. The crowding of adult beetles in egg production units (cups) had a significant, negative effect on egg production per beetle but the total egg production per cup was still higher with higher number of beetles per cup resulting in a significant saving of labor per egg produced. Larval survival rates in alfalfa-planted cans were surprisingly low given the protected conditions of the greenhouse. The larval survival rates were not significantly different among the dates for the second instar and later instars, suggesting that larval mortality occurs in the first instar in alfalfa-planted cans