Audio formatting—Making spoken text and math comprehensible

A_ST_ER is an interactive computing system foraudio formatting electronic documents (presently, documents written in (LA)T_EX) to produce audio documents. A_ST_ER can speak both literary texts and highly technical documents that contain complex mathematics. In fact, the effective speaking of mathematics is a key goal of A_ST_ER. To this end, a listener can request that segments of text or mathematics be spoken using several diffent rendering styles, in an interactive fashion. Listeners can themselves construct rendering rules and styles, if they feel it necessary.In this paper, we describe the rendering component of A_ST_ER—the system for writing rules for speaking various parts of text and mathematics-and discuss some of the principles that were used in developing rules for making spoken text, mathematics, and tables comprehensible.Visual communication is characterized by the eye's ability to actively access parts of a two-dimensional display. The reader is active, while the display is passive. This active-passive role is reversed by the temporal nature of oral communication: information flows actively past a passive listener. This prohibits multiple views—it is impossible to first obtain a high-level view and then look at details. These shortcomings become severe when presenting complex mathematics orally.Audio formatting, which renders information structure in a manner attuned to an auditory display, overcomes these problems. Audio layout, composed of fleeting and persistent cues, conveys complex structure without detracting from the content. A_ST_ER is interactive, and the ability to browse information structure and obtain multiple views enablesactive listening.     

Composition mapping in InGaN by scanning transmission electron microscopy

We suggest a method for chemical mapping that is based on scanning transmission electron microscopy (STEM) imaging with a high-angle annular dark field (HAADF) detector. The analysis method uses a comparison of intensity normalized with respect to the incident electron beam with intensity calculated employing the frozen lattice approximation. This procedure is validated with an In_0.07Ga_0.93N layer with homogeneous In concentration, where the STEM results were compared with energy filtered imaging, strain state analysis and energy dispersive X-ray analysis. Good agreement was obtained, if the frozen lattice simulations took into account static atomic displacements, caused by the different covalent radii of In and Ga atoms. Using a sample with higher In concentration and series of 32 images taken within 42 min scan time, we did not find any indication for formation of In rich regions due to electron beam irradiation, which is reported in literature to occur for the parallel illumination mode. Image simulation of an In_0.15Ga_0.85N layer that was elastically relaxed with empirical Stillinger-Weber potentials did not reveal significant impact of lattice plane bending on STEM images as well as on the evaluated In concentration profiles for specimen thicknesses of 5, 15 and 50 nm. Image simulation of an abrupt interface between GaN and In_0.15Ga_0.85N for specimen thicknesses up to 200 nm showed that artificial blurring of interfaces is significantly smaller than expected from a simple geometrical model that is based on the beam convergence only. As an application of the method, we give evidence for the existence of In rich regions in an InGaN layer which shows signatures of quantum dot emission in microphotoluminescence spectroscopy experiments.     

Aggregation Pheromone of Palm Weevil, Dynamis borassi

4-Methyl-5-nonanol (1) is the male-produced aggregation pheromone of the palm weevil, Dynamis borassi (F.) from Colombia. The pheromone was identified by coupled gas chromatographic–electroantennographic detection (GC-EAD) analysis of male- and female-produced volatiles, and comparative GC–mass spectrometry (MS) of weevil-produced 1. In field experiments in Colombia, traps baited with a stereoisomeric mixture of synthetic 1 (3 mg/day) plus sugarcane captured more weevils than traps baited with 1 or sugarcane alone, suggesting that pheromone and plant volatiles are synergistically attractive. Use of a chiral, stereoisomer-separating Cyclodex-B column in GC-EAD and GC-MS analyses revealed that D. borassi males produce, and antennae of males and females respond to (4S,5S)-1. Previously identified palm weevil (Rhynchophorus spp.) aggregation pheromones 5-methyl-4-octanol (cruentol) and 6-methyl-2-hepten-4-ol (rhynchophorol) also elicited antennal responses by D. borassi. In field experiments, D. borassi females were captured equally well in traps baited with sugarcane plus either 1, cruentol or rhynchophorol. In contrast, D. borassi males were captured most often in traps baited with sugarcane plus 1. Because D. borassi is a potential vector of the red ring nematode that causes the lethal red ring disease of palms, pheromone-based trapping of D. borassi could aid in monitoring or management of red ring disease in commercial palm plantations.     

(E4,E10)-dodecadienyl acetate: Novel sex pheromone component of tentiform leafminer,Phyllonorycter mespilella (Hübner) (Lepidoptera: Gracillariidae)

(E4,E10)-dodecadienyl acetate (E4,E10-12OAc) is a newly discovered sex pheromone component of the tentiform leafminer,Phyllonorycter mespilella (Hübner). In apple orchards, traps baited with 1g ofE4,E1012OAc attractedP. mespilella in British Columbia andP. blancardella (F.) in Massachusetts and Nova Scotia. The compound was identified inP. mespilella by gas chromatographic-electroantennographic analysis (GC-EAD) of pheromone gland extracts, retention index calculations, EAD profiles toE3 toE10 dodecenyl acetates, and synthesis of candidate pheromone components. Even thoughE4,E10-12OAc was not detected in gland extracts by GC-mass spectroscopy, several factors indicate that it is female-produced. Antennal responses to gland extracts coincided with authenticE4,E10-12OAc on four GC columns with different retention characteristics.E4,E10-12OAc andE10-12OAc, a known female-produced pheromone component, elicited equally strong EAD responses. In field tests,E4,E10-12OAc was two to four times more attractive thanE10-12OAc. There was no additive or synergistic effect between the two components.     

(S,S)-2,12-, (S,S)-2,13-, and (S,S)-2,14-diacetoxyheptadecanes: sex pheromone components of red cedar cone midge, Mayetiola thujae

We identified, synthesized, and field-tested the sex pheromone of female red cedar cone midge Mayetiola thujae (Hedlin) (Diptera: Cecidomyiidae), a pest insect in red cedar Thuja plicata seed orchards. Coupled gas chromatographic (GC)-electroantennographic detection analyses of pheromone extract revealed three components (A, B, C) that elicited responses from antennae of males, all of which occurred below the detection threshold of the mass spectrometer and thus had to be identified without spectroscopic data. Taking into account (1) their retention indices (RI) on three GC columns (DB-5, DB-23, and DB-210), (2) intercolumn RI differentials, and (3) the molecular structures of known cecidomyiid pheromones, we synthesized seven candidate pheromone components: 2,10-, 2,11-, 2,12-, 2,13-, 2,14-, 2,15- and 2,16-diacetoxyheptadecanes. Of these, 2,12-, 2,13-, and 2,14-diacetoxyheptadecane had RIs on all columns consistent with those of A, B, and C and elicited strong antennal responses when tested at picogram levels. In field experiments with the twelve stereoselectively synthesized stereoisomers, only the SS-stereoisomers of 2,12-, 2,13-, and 2,14-diacetoxyheptadecane attracted male M. thujae. The three-component SS-stereoisomer blend was more attractive than the 12-component blend of all stereoisomers, suggesting that one or several nonnatural stereoisomers are inhibitory. One-, two-, and three-component lures of the SS-stereoisomers were equally effective in attracting male M. thujae, indicating redundancy in the pheromone. Identification of the M. thujae sex pheromone will allow development of pheromone-based monitoring, and possibly control, of M. thujae populations in T. plicata seed orchards.     

Alarm Pheromone System of the Western Conifer Seed Bug, Leptoglossus occidentalis

The alarm pheromones for adult and nymphal western conifer seed bugs, Leptoglossus occidentalis, were collected from the headspace volatiles of agitated bugs and from extracted adult thoraxes and nymphal abdomens. Adult bugs secreted a blend from the metathoracic glands that consisted of hexyl acetate, hexanal, hexanol, heptyl acetate, and octyl acetate (ratio of 152:103:8:1.5:1). Nymphal alarm pheromone produced by the dorsal abdominal glands consisted of (E)-2-hexenal. Agitated adults emitted 24% of the pheromone contained within the glands, while nymphs released 33% of their constitutive supply. The complete blend from both adults and nymphs, tested in a laboratory headspace bioassay, elicited a dispersal (or alarm) response in >70% of individuals tested. Nymphs in the field exposed to synthetic adult or nymphal pheromones, or a mixture of both, responded with >50% dispersing. When single components were tested on adults reared under summer conditions in a forced-air one-way bioassay, hexanal and hexyl acetate, the major components of the secretion, were responsible for eliciting the alarm response. Adults collected in the fall from the field were unresponsive to the tested blend, suggesting that adults seeking aggregation sites in the fall become refractory to alarm pheromone stimuli that would cause aggregations to disperse. The weak dispersal responses elicited in both adults and nymphs by either nymphal or adult pheromones are consistent with a tradeoff in the advantage gained by avoiding predation and the disadvantage of leaving a food source. Because of these weak responses, use of alarm pheromones as pest management tools against L. occidentalis is unlikely.     

(E)- and (Z)-6-nonen-2-one: Biosynthetic precursors ofEndo- andexo-brevicomin in two bark beetles (Coleoptera: Scolytidae)

The ability of (E)- and (Z)-6-nonen-2-one to serve as precursors of the common scolytid pheromonesEndo- andexo-brevicomin was examined in vivo. When mountain pine beetles (MPB),Dendroctonus ponderosae Hopkins, or western balsam bark beetles (WBBB),Dryocoetes confusus Swaine, were exposed to [6,7-D₂](E)-6-nonen-2-one, theEndo-brevicomin produced was enriched with two deuterium atoms per molecule (as determined by GC-MS), indicating that (E)-6-nonen-2-one served as a precursor of this pheromone. Similarly, when the beetles were exposed to [4,4-D₂](Z)-6-nonen-2-one, theexo-brevicomin produced was enriched with two deuterium atoms per molecule. Evidence in support of biological relevance of the latter observation include: (1) (Z)-6-nonen-2-one was found in the volatiles of male MPBs and WBBBs, indicating that this is a natural metabolite; (2) theexo-brevicomin produced by MPB was shown to be of natural (+) chirality by complexation chromatography; and (3) female WBBBs and MPBs (which are not known to produceexo-brevicomin) produced significantly lessexo-brevicomin when exposed to the precursor than did the males.     

Communication ecology of webbing clothes moth: 1. Semiochemical-mediated location and suitability of larval habitat

We tested two hypotheses: 1) that there is semiochemical-mediated attraction of male and female webbing clothes moth (WCM), Tineola bisselliella (Hum.) (Lepidoptera: Tineidae) to suitable larval habitat; and 2) that selection of optimal larval habitat has fitness consequences. In binary or ternary choice arena bioassay experiments that prevented WCM from contacting test stimuli, males and females were attracted to dried but untanned animal pelts (red squirrel, muskrat, beaver, coyote, red fox and bobcat) and preserved horseshoe crab but not to unprocessed sheep's wool, demonstrating semiochemical-based recognition of, and discrimination between, potential larval habitats. Selection of habitat has fitness consequences for ovipositing females, because significantly more male and female WCM completed development when the larval diet consisted of intact animal pelt (hide plus hair) rather than hide or hair alone. Equal attraction of male WCM to muskrat pelt volatiles in Porapak Q or solvent extracts of muskrat pelts indicated that volatile semiochemicals could be obtained by both methods.     

Volatile compounds released by disturbed and calm adults of the tarnished plant bug,Lygus lineolaris

Volatile compounds released by disturbed and calm female and male Lygus lineolaris were collected and analyzed. Six major compounds were present in samples from disturbed bugs and from calm females: (E)-2-hexenal, 1-hexanol, (E)-2-hexenol, hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-2,4-oxohexenal. (E)-2-hexenal was lacking in volatiles collected from calm males. Hexyl butyrate accounted for approximately 68% and 66% of volatiles released by agitated and calm females, and 87% and 88% of volatiles released by agitated and calm males, respectively. Blends released by disturbed insects differed quantitatively from blends released by calm insects, with amounts of compounds increasing 75–350 times in samples from disturbed insects. In static air bioassays, both females and males were repelled by natural volatiles collected from females and by five-component [(E)-2,4-oxohexenal excluded] and six-component synthetic blends at doses of 1 and 10 bug-hours, indicating that these volatiles may serve an alarm or epideictic function, as well as a possible role as defensive allomones. Adults also avoided hexyl butyrate, (E)-2-hexenyl butyrate, (E)-2-hexenol, and (E)-2,4-oxohexenal, but not 1-hexanol and (E)-2-hexenal when compounds were assayed individually in static air bioassays at doses equal to 1 bug-hour. When tested over 1 day in two-choice cage trials, adults did not prefer untreated bean plants over bean plants surrounded by vials releasing up to 8.1 mg/hr (=234 bug-hours) of the five-component synthetic blend. Therefore, the volatiles produced by disturbed adults would not be useful as a repellent for L. lineolaris.