The photogeneration of 2,3,9,10-tetrabromopentacene from its precursor dione by photodecarbonylation was investigated. An unusual photodimer, 3,3',9,9',10,10'-hexabromo-2,2'-bipentacene, is produced.

We compute asymptotic series for Hofstadter’s figure-figure sequences.

We present a novel, robust and accurate blood velocity estimation technique that is implementable by elementary digital signal processing. In this technique, echoes from repeated firings of a transducer are resampled along a set of predetermined trajectories of constant velocities, called "butterfly lines" because of their intersection at a reference range. The slope of the trajectory on which ...

Butterfly community and single species based approaches were taken to establish conservation priorities within a nature reserve in Central Spain. In this study, patch type (sclerophyllous, halophilous, or disturbed), potential herbaceous nectar availability, potential woody plant nectar availability, total nectar availability, and two approximations to plant diversity (herbaceous and woody plan...

While butterfly responses to climate change are well studied, detailed analyses of the seasonal dynamics of range expansion are few. Therefore, the seasonal range expansion of the butterfly Heliconius charithonia L. (Lepidoptera: Nymphalidae) was analyzed using a database of sightings and collection records dating from 1884 to 1992 from Texas. First and last sightings for each year were noted, ...

OBJECTIVE To evaluate the effect on snoring of structural nasal valve dilatation with butterfly spreader grafts in patients with nasal valve insufficiency. DESIGN Retrospective medical chart review and telephone follow-up; mean +/- SD follow-up time, 20.7 +/- 11.34 months (range, 3-48 months). SETTINGS Tertiary care referral center. SUBJECTS A total of 37 snoring patients with nasal valve...

PURPOSE To compare corneal reepithelialization, pain scores, ocular discomfort, and tear production after photorefractive keratectomy (PRK) and butterfly laser epithelial keratomileusis (LASEK). METHODS This prospective, randomized, double-masked study comprised 102 eyes of 51 patients who underwent laser refractive surgery. Each patient was randomized to have one eye operated on with PRK and...

Infection by endosymbiotic bacteria is an underappreciated threat to endangered arthropods with serious implications for captive management programs. We examined the nature of Wolbachia infection in the North American endangered Karner blue butterfly, Lycaeides melissa samuelis, as a case study. Screening for Wolbachia across the range of the species confirmed widespread infection in the wester...

Research has shown that the mere presence of stimuli that resemble eyes is sufficient to attract attention, elicit aesthetic responses, and can even enhance prosocial behavior. However, it is less clear whether eye-like stimuli could also be used as a tool for nature conservation. Several animal species, including butterflies, develop eye-like markings that are known as eyespots. In the present...

Based on the super light trapping property of butterfly Trogonoptera brookiana wings, the SiO2 replica of this bionic functional surface was successfully synthesized using a simple and highly effective synthesis method combining a sol-gel process and subsequent selective etching. Firstly, the reflectivity of butterfly wing scales was carefully examined. It was found that the whole reflectance s...