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At least 199 records · Page 11Linked to original sources
PubMed2005

Gene expression of ecdysteroid-regulated gene E74 of the honeybee in ovary and brain.

To facilitate studies of hormonal control in the honeybee (Apis mellifera L.), a cDNA for a honeybee homologue of the ecdysteroid-regulated gene E74 (AmE74) was isolated and its expression was analysed. Northern blot analysis indicated strong expression in the adult queen abdomen, and no significant expression in the adult drone and worker abdomens. In situ hybridization demonstrated that this gene was expressed selectively in the ovary and gut in the queen abdomen. Furthermore, this gene was also expressed selectively in subsets of mushroom body interneurones in the brain of the adult worker bees. These findings suggest that AmE74 is involved in neural function as well as in reproduction in adult honeybees.

Amino Acid Sequence↗
PubMed2006

Proteomic analyses of male contributions to honey bee sperm storage and mating.

Honey bee (Apis mellifera L.) queens mate early in life and store sperm for years. Male bees likely contribute significantly to sperm survival. Proteins were extracted from seminal vesicles and semen of mature drones, separated by electrophoresis, and analysed by peptide mass fingerprinting. Computer searches against three databases, general species, honey bees and fruit flies, were performed. Spectra were used to query the recently generated honey bee genome protein list as well as general species and fruit fly databases. Of the 69 unique honey bee proteins found, 66 are also in Drosophila melanogaster. Two proteins only matched honey bee genes and one is a widespread protein lost from the fly genome. There is over-representation of genes implicated in the glycolysis pathway. Metabolism-associated proteins were found primarily in the seminal vesicle. Male accessory gland proteins as identified in Drosophila rarely had orthologs among proteins found in the honey bee. A complete listing of gel spots chosen including honey bee genome matches and Mascot searches of MALDI-TOF results with statistics is in the Supplementary table. MALDI-TOF spectra and more complete Mascot peptide mass fingerprinting data are available on request. Supplementary figs 1-3 show the stained protein gels.

Animals↗
PubMed2006

Vocal tract resonances and the sound of the Australian didjeridu (yidaki) I. experiment.

The didjeridu, or yidaki, is a simple tube about 1.5 m long, played with the lips, as in a tuba, but mostly producing just a tonal, rhythmic drone sound. The acoustic impedance spectra of performers' vocal tracts were measured while they played and compared with the radiated sound spectra. When the tongue is close to the hard palate, the vocal tract impedance has several maxima in the range 1-3 kHz. These maxima, if sufficiently large, produce minima in the spectral envelope of the sound because the corresponding frequency components of acoustic current in the flow entering the instrument are small. In the ranges between the impedance maxima, the lower impedance of the tract allows relatively large acoustic current components that correspond to strong formants in the radiated sound. Broad, weak formants can also be observed when groups of even or odd harmonics coincide with bore resonances. Schlieren photographs of the jet entering the instrument and high speed video images of the player's lips show that the lips are closed for about half of each cycle, thus generating high levels of upper harmonics of the lip frequency. Examples of the spectra of "circular breathing" and combined playing and vocalization are shown.

Acoustics↗
PubMed1992

Acoustics and perception of overtone singing.

Overtone singing, a technique of Asian origin, is a special type of voice production resulting in a very pronounced, high and separate tone that can be heard over a more or less constant drone. An acoustic analysis is presented of the phenomenon and the results are described in terms of the classical theory of speech production. The overtone sound may be interpreted as the result of an interaction of closely spaced formants. For the lower overtones, these may be the first and second formant, separated from the lower harmonics by a nasal pole-zero pair, as the result of a nasalized articulation shifting from /c/ to /a/, or, as an alternative, the second formant alone, separated from the first formant by the nasal pole-zero pair, again as the result of a nasalized articulation around /c/. For overtones with a frequency higher than 800 Hz, the overtone sound can be explained as a combination of the second and third formant as the result of a careful, retroflex, and rounded articulation from /c/, via schwa /e/ to /y/ and /i/ for the highest overtones. The results indicate a firm and relatively long closure of the glottis during overtone phonation. The corresponding short open duration of the glottis introduces a glottal formant that may enhance the amplitude of the intended overtone. Perception experiments showed that listeners categorized the overtone sounds differently from normally sung vowels, which possibly has its basis in an independent perception of the small bandwidth of the resonance underlying the overtone. Their verbal judgments were in agreement with the presented phonetic-acoustic explanation.

Fourier Analysis↗
PubMed1994

Characterization of the putative fusogenic domain in vesicular stomatitis virus glycoprotein G.

The envelope glycoprotein G of vesicular stomatitis virus induces membrane fusion at low pH. Site-directed mutagenesis of specific amino acids within a segment spanning amino acids 123 to 137 of G protein, which is highly conserved in vesiculoviruses and was previously shown by us to be involved in fusogenic activity (Y. Li, C. Drone, E. Sat, and H. P. Ghosh, J. Virol. 67:4070-4077, 1993), was used to determine the role of this region in low-pH-induced membrane fusion. The mutant glycoproteins expressed in COS cells were assayed for acid-pH-induced cell-cell fusion. Substitution of the variant Pro-123 with Leu had no effect on the fusogenic activity, while substitution of conserved Phe-125 and Asp-137 with Tyr and Asn, respectively, shifted the pH optimum of membrane fusion to a more acidic pH value and decreased the fusion efficiency. The deletion of amino acid residues 124 to 127, 131 to 137, or 124 to 137 produced mutants defective in transport. Mutation of the conserved residues Gly-124 and Pro-127 to Ala and to Gly or Leu, respectively, inhibited cell-cell fusion activity by about 90% without affecting transport of the mutant proteins to the cell surface, suggesting that these two residues may be present within the fusion peptide and thus may be directly involved in fusion. This highly conserved domain containing neutral amino acids of G protein may therefore represent the putative fusion domain of vesicular stomatitis virus G protein.

Amino Acid Sequence↗
PubMed1996

Semiochemical parsimony in the Arthropoda.

A wide variety of arthropods have adapted their own semiochemicals to subserve multiple functions in diverse contexts. Semiochemicals, the pheromones and allomones, have been detected in arthropod species in six orders, and it has been clearly established that these compounds are used with great parsimony. The versatility of these invertebrates in using these natural products for an incredible diversity of functions emphasizes the significance of semiochemicals in the evolutionary biology of Arthropoda. Multifunctional pheromones have proved to be especially characteristic of the queens of eusocial species. Compounds such as the queen substance of the honey bee, Apis mellifera, possess unrelated primer and releaser functions for the workers and act as a sex attractant for drones. Females of other hymenopterous species exploit the secretions of sting-associated glands as sex pheromones, whereas a variety of nonhymenopterous species have adapted components in diverse defensive secretions to function as sex pheromones. The alarm pheromones of many arthropods are also used as defensive allomones, activity inhibitors, cryptic alarm pheromones, aggregative attractants, robbing agents, digging agents, trail pheromones, and antimicrobial agents. Defensive allomones also possess some of these parsimonious roles; in addition, however, some of these compounds possess highly distinctive roles, such as functioning as lethal attractants for prey, or, in he aquatic milieu, cuticular wetting agents. Clearly, the availability of a variety of pheromones and allomones has enabled arthropods to evolve an elegant semiochemical parsimony with which to exploit the biological milieu.

Journal Article↗
PubMed2002

Behavioral studies of learning in the Africanized honey bee (Apis mellifera L.).

Experiments on basic classical conditioning phenomena in adult and young Africanized honey bees (Apis mellifera L.) are described. Phenomena include conditioning to various stimuli, extinction (both unpaired and CS only), conditioned inhibition, color and odor discrimination. In addition to work on basic phenomena, experiments on practical applications of conditioning methodology are illustrated with studies demonstrating the effects of insecticides on learning and the reaction of bees to consumer products. Electron microscope photos are presented of Africanized workers, drones, and queen bees. Possible sub-species differences between Africanized and European bees are discussed.

Animals↗
PubMed2004

Identification and analysis of the minimal promoter activity of a novel noncoding nuclear RNA gene, AncR-1, from the honeybee (Apis mellifera L.).

Previously, we identified a gene for a noncoding nuclear RNA, termed Ks-1, that is expressed preferentially in a restricted set of neurons in the honeybee brain. In the present study, we identified another novel gene, termed AncR-1, whose transcripts were localized to nuclei in the whole cortex region of the honeybee brain, as a candidate novel noncoding nuclear RNA gene. RNA fluorescent in situ hybridization revealed that AncR-1 and Ks-1 transcripts were located in a distinct portion of a single neural nucleus, suggesting that they have distinct functions in brain neurons. cDNA cloning revealed that the AncR-1 transcripts were up to 7 kb in size, had mRNA-like structures, and were alternatively spliced. The reporter assay using Drosophila SL-2 cells demonstrated that a TATA box-like sequence located -30 bp upstream of the 5' end of AncR-1 cDNA had promoter activity. None of the alternatively spliced AncR-1 cDNA variants contained significant open reading frames, strongly suggesting that AncR-1 transcripts function as novel noncoding nuclear RNAs. Furthermore, in situ hybridization revealed that AncR-1 was expressed not only in the brain but also in the sex organs in the queen and drones and in the hypopharyngeal glands and oenocytes of the worker bees, suggesting that AncR-1 is involved in diverse organ functions. Some of the AncR-1 transcripts enriched in the nuclei of the hypopharyngeal glands were polyadenylated, indicating the presence of mRNA-like AncR-1 transcripts in the nuclei.

Animals↗
PubMed2004

Countertransference revisited.

A female patient of mine recounts her week. I listen with interest, waiting for her to arrive at particular conclusions. She has suffered a great deal and still does, but prefers not to dwell on it. My interest turns into patience as she continues to talk but circumvents her discontent. She is adroit at avoidance, but easily offended when I point such things out. "I'd better wait" I think. I grow more aware that I must encourage her digressions. I feel frustrated. Getting further and further away, she skirts the issue with supple grace, then strays off into tangentiality. I forget her point and lose my focus, then get down on myself. The opportunity is soon gone. I glance at the clock as her monologue drones on into banality. I grow more uninterested and distant. There is a subtle irritation to her voice; a whiney indecisive ring begins to pervade my consciousness. I home in on her mouth with aversion, watching apprehensively as this disgusting hole flaps tirelessly but says nothing. It looks carnivorous, voracious. Now she is unattractive, something I have noticed before. I forget who my next patient is. I think about the meal I will prepare for my wife this evening, then glance at the time once more. Then I am struck: Why am I looking at the clock? So soon? The session has just begun. I catch myself. What is going on in me, between us? I am detached, but why? Is she too feeling unattuned, disconnected? I am failing my patient. What is her experience of me? I lamentingly confess that I do not feel I have been listening to her, and wonder what has gone wrong between us. I ask her if she has noticed. We talk about our feelings, our impact on one another, why we had lost our sense of connection, what it means to us. I instantly feel more involved, rejuvenated, and she continues, this time with me present. Her mouth is no longer odious, but sincere and articulate. She is attractive and tender; I suddenly feel empathy and warmth toward her. We are now very close. I am moved. Time flies, the session is soon over; we do not want it to end.

Countertransference↗
PubMedDate not supplied

Light modulates electric phenomena in hornet cuticle.

In the cuticle of live social hornets, such as Vespa orientalis (Hymenoptera, Vespinae), endogenous electric effects are encountered, i.e. voltages of 100-200 mV under illumination and currents amounting to several microamperes on its subjection to darkness-clearly a process of charging and discharging. Of the various wavelengths of sunlight, UV was found to be the most contributory to the active cuticular voltage generation. Throughout the warm season of the year--the active period in colonies of social hornets and wasps--colony members exit from the dark nest during the daytime and fly to the field under the hot sun for various foraging purposes, ultimately returning to the nest. Thus, each hornet, be it queen, worker or drone, probably undergoes daily cyclical process of electric charge and discharge in the exterior part of their integument, cuticle, which lasts up to 30-40 min. Such photoelectric phenomenon was detected in both live, ether-anaesthetized hornets and dead hornets, albeit in the latter the electric values recorded were lower. The present study addresses the possible impact of the phenomenon on vespan daily life and also compares it with a parallel occurrence in electric fish.

Animals↗
PubMed2001

Varroa destructor infestation in untreated honey bee (Hymenoptera: Apidae) colonies selected for hygienic behavior.

Honey bee (Apis mellifera L.) colonies bred for hygienic behavior were tested in a large field trial to determine if they were able to resist the parasitic mite Varroa destructor better than unselected colonies of"Starline" stock. Colonies bred for hygienic behavior are able to detect, uncap, and remove experimentally infested brood from the nest, although the extent to which the behavior actually reduces the overall mite-load in untreated, naturally infested colonies needed further verification. The results indicate that hygienic colonies with queens mated naturally to unselected drones had significantly fewer mites on adult bees and within worker brood cells than Starline colonies for up to 1 yr without treatment in a commercial, migratory beekeeping operation. Hygienic colonies actively defended themselves against the mites when mite levels were relatively low. At high mite infestations (>15% of worker brood and of adult bees), the majority of hygienic colonies required treatment to prevent collapse. Overall, the hygienic colonies had similar adult populations and brood areas, produced as much honey, and had less brood disease than the Starline colonies. Thus, honey bees bred for hygienic behavior performed as well if not better than other commercial lines of bees and maintained lower mite loads for up to one year without treatment.

Animals↗
PubMed2003

Field trials using the fungal pathogen, Metarhizium anisopliae (Deuteromycetes: Hyphomycetes) to control the ectoparasitic mite, Varroa destructor (Acari: Varroidae) in honey bee, Apis mellifera (Hymenoptera: Apidae) colonies.

The potential for Metarhizium anisopliae (Metschinkoff) to control the parasitic mite, Varroa destructor (Anderson and Trueman) in honey bee colonies was evaluated in field trials against the miticide, tau-fluvalinate (Apistan). Peak mortality of V. destructor occurred 3-4 d after the conidia were applied; however, the mites were still infected 42 d posttreatments. Two application methods were tested: dusts and strips coated with the fungal conidia, and both methods resulted in successful control of mite populations. The fungal treatments were as effective as the Apistan, at the end of the 42-d period of the experiment. The data suggested that optimum mite control could be achieved when no brood is being produced, or when brood production is low, such as in the early spring or late fall. M. anisopliae was harmless to the honey bees (adult bees, or brood) and colony development was not affected. Mite mortality was highly correlated with mycosis in dead mites collected from sticky traps, indicating that the fungus was infecting and killing the mites. Because workers and drones drift between hives, the adult bees were able to spread the fungus between honey bee colonies in the apiary, a situation that could be beneficial to beekeepers.

Animals↗
PubMed1981

An analysis and reduction of disruptive behavior on school buses.

Thousands of children are injured or killed each year in school bus accidents. A significant number of these tragic incidents is precipitated by disruptive child behavior that distracts the drivers from their difficult task. Two experiments were conducted which addressed this problem. For both experiments an automated sound recording device (referred to as a Noise Guard) selectively responsive to frequencies above 500 Hz (i.e., unresponsive to bus drone) recorded both the duration and frequency of noise outbursts above a tolerable threshold. Additionally, an observer made in situ measurements of other disruptions including roughhousing and getting-out-of-seat. In the first experiment, following baseline measurements of these behaviors, middle-school students received feedback for noise outbursts. That is, when "Noise Guard" was activated, it in turn operated one of several lights on a panel visible to all passengers. Each day students were allowed to listen to high-appeal taped music while riding the bus and to participate in a raffle for prizes, provided the number of outbursts on the preceding day remained below a specified criterion indicated on the light panel. This intervention resulted in drastic reductions of noise outbursts with a concomitant reduction in other disruptive behaviors. Comparable results were obtained in the second experiment which eliminated the raffle from the intervention.

Adolescent↗
PubMed2001

Thermal properties of hornet colonies: thermography of individual hornets and their nests and the role of the pupal silk in thermoregulation.

The present study focused on temperature assessments within a hornet nest. The measurements encompassed adult hornets, brood combs and the various stages of brood, and involved a thermographic method. Body parts of adult hornets were found to vary in their temperature, with the thorax eliciting the highest temperature and the abdomen the lowest. Similarly, there were thermal variances between larvae at instars 4-5, light-colored pupae and dark pupae. The measurements were made at day and night (when the entire population was present in the nest) on nests containing thousands of individuals at various ages. Most of the pupae measured during October were hornet drones. The usual air temperature between the (subterranean) combs was 28.7 degrees C, while the outside (ground level) temperature was 23.5 degrees C. The paper discusses the creation of heat by hornets, the thermoregulation throughout night and day, both by the hornets proper as well as by their products (comb and silk). Also discussed is the intra-nest conversion of one form of energy to another, as heat to electric current or vice versa.

Animals↗
PubMed2002

[Spring propagation and size dynamics characteristics of two kinds of bee populations in Anhui Province].

Systematical observations and researches were conducted on the population size dynamics of Apis mellifera Ligustica Spi. and Apis cerana cerana Feb. in Wanzhong, Wanxi and Wannan mountainous area in Anhui Province in 1997-1999. The results showed that the bee population size was influenced by climate and flower fertility, which was higher in Spring and Autumn, and lower in Summer and Winter. The propagation and renewal of A. mellifera in Autumn were quicker than those of A. cerana cerana, while the effect of overcoming Summer was inferior to that of Apis cerana cerana. The sex ratio of A. mellifera was (314.4 +/- 289.9):1-(329.4 +/- 305.8):1, and that of A. cerana cerana was (334.2 +/- 235.5):1-(413.1 +/- 377.2):1. The birth of drones was seasonal, and the age structure of each bee population was variable.

Animals↗
PubMed2003

Effects of the beehive type and queen-bee descent on the development of the bee-diseases at apiaries.

An increased occurrence of disease at various members of the honeybee brood (queen-bee, workers, and drones) settled in the beehive, become evident recently. It is already known that various factors, primary ecological, determine disease development. The aim of the study was to discover which diseases at apiaries corresponds to similar ecological conditions at different beehive types. Effects of the following factors were studied: beehive type and building material, type and descent of the queen-bee, variable of the environmental conditions. All honeybee broods, belonging to the European Apis mellifera carnica rase, used identical honeyfull plants pastures.

Agriculture↗
PubMed2004

[Beehive social organisation and biology of the Varroa mite].

In this paper we deal with the social structure of a honeybee colony. Kind of interactions among the individuals of the three castes relatively to their task (queen, drone, workers) are recorded. Moreover taxonomic and biological information is given on the Varroa mite, Varroa destructor (Acari: Varroidae) and its interaction with the host.

Animals↗
PubMed2003

Photo-induced arousal response by hornets.

When an Oriental hornet Vespa orientalis is subjected to ether anesthesia and then exposed to ultraviolet A light (UVAL) (at a wavelength of 366 nm), it commences showing signs of awakening by starting to move its limbs. While in the process of waking the voltage on its body surface surges sharply from 17-180 mV (median = 71.0) to a level of 93-570 mV (median = 327.5). This elevated level is maintained for several minutes but subsequently drops sharply to starting level. The increase in voltage is throughout accompanied by fluttering of the wings and movements of the legs, as well as attempts to extricate itself from the bindings to the electrodes. These movements by the awakening hornet persist for several minutes even after the irradiation source is turned off but shortly after the switch-off the hornet lapses into sleep again. The described scenario is generally similar in worker, queen and drone hornets, and may even occur in decapitated specimens. The same type of awakening can be repeated in the same fashion after a while, but then the increase in voltage will be smaller than the first time. Continuous UV irradiation of an anesthetized hornet results in a generalized and protracted awakening which, however, is significantly shorter than in a hornet left anesthetized in the dark.

Animals↗