Search results for "bosc"
showing 10 items of 115 documents
Pollination biology in Roepera (Zygophyllaceae): How flower structure and shape influence foraging activity
2019
The foraging behavior of bees is a complex phenomenon that depends on numerous physical features of flowers. Of particular importance are accessibility of floral rewards, floral proportions, symmetry and orientation. The flowers of Roepera are characterized by the presence of staminal scales (SS), which play an important role in nectar protection. We studied two species of Roepera with different symmetry and flower orientation, which are mainly visited by honeybees (Apis mellifera). We aimed to show how the foraging behavior of honey bees is affected by the function of SS, floral symmetry and orientation. The foraging behavior was documented by video photography. Handling time, access to ne…
Northward invasion of the parasitic deer ked ( Lipoptena cervi), is there geographical variation in pupal size and development duration?
2010
SUMMARYThe deer ked (Lipoptena cervi) is a common ectoparasite of cervids. During the last decades the species has rapidly invaded in northern Europe, especially in Finland, towards the north and increased its prevalence on the moose population. Consequently, during this rapid invasion the deer ked has faced more severe climatic conditions. We studied whether pupal size (measured as pupal weight) and pupal development duration of the deer ked varies along historical invasion zones and temperature zones towards north in Finland. Moreover, we explored possible size- and gender-dependent variation in pupal development duration. We divided wild-collected pupae in respect to their origin in two …
Avian predation on a parasitic fly of cervids during winter: can host-related cues increase the predation risk?
2012
The deer ked (Lipoptena cervi) is an ectoparasitic fly on cervids that has expanded its distribution rapidly in Northern Europe. However, the regulating biotic factors such as predation remain unknown. The host-independent pupal stage of the fly lasts for several months. Blackish pupae are visible against snow, especially on the bedding sites of hosts, and are thus exposed to predators. To evaluate the role of predation on the invasion dynamics and evolution of L. cervi, we monitored pupal predation on artificial bedding sites in three geographical areas in Finland during winter. We explored: (1) possible predators; (2) magnitude of predation; and (3) whether predation risk is affected by h…
Summer time predation on the obligatory off-host stage of an invasive ectoparasite
2016
SUMMARYPredation can regulate populations and strongly affect invasion success of novel prey. The deer ked (Lipoptena cervi; Linnaeus 1758) is an invasive ectoparasite of cervids that spends a long period of its life cycle outside the host. Prior to this study, virtually nothing was known about natural summer time predation on the deer ked. We aimed to evaluate the magnitude of summer time predation onL. cervipupae in different habitats and to identify potential predators. We conducted a set of field experiments, where we exposedL. cervipupae to various ground-dwelling vertebrate and invertebrate predators. The loss of pupae was monitored for different predator guilds. Three habitats of the…
A Revised Phylogeny of Discocerinini (Diptera: Ephydridae) with an Emphasis on Structures of the Proboscis
2016
Supplementary diagnostic characters of genera in the tribe Discocerinini are suggested. A new genus Aquachasma Zatwarnicki, type species: Discocerina leucoprocta Loew, 1861 is described with 24 new combinations of all included species. Genus Polytrichophora is divided into the nominate subgenus and a new subgenus Sklodowskopa Zatwarnicki, type species: Clasiopa duplosetosa Becker, 1896. Genus Orasiopa is divided into the nominate subgenus and a new subgenus Reymontopa Zatwarnicki, type species: Discocerina mera Cresson, 1939. The shape of the proboscis of all genera of Discocerinini is provided, including variability of cibarium and pseudotracheae. The ventral receptacles of 6 genera (Aquac…
A model for torque losses in variable displacement axial piston motors
2018
This paper includes a comparison of earlier presented models for torque losses in hydraulic motors and several proposed models that all rely on data typically available for a system engineer. The new models and the old ones are compared. The new models are all based on a model developed by Jeong 2007 with an expansion that include variable displacement. All of the new models yield very good accuracy down to approximately 50% of maximum displacement and down to approximately 15% of maximum speed. In these operational ranges the deviation in torque is less than 1%. The main purpose of the new models is to facilitate simulations of hydraulically actuated winches with a balance between accuracy…
Morphology, performance and attachment function in Corynosoma spp. (Acanthocephala)
2018
Background: Functional inference on the attachment of acanthocephalans has generally been drawn directly from morphology. However, performance of structures is often non-intuitive and context-dependent, thus performance analysis should be included whenever possible to improve functional interpretation. In acanthocephalans, performance analysis of attachment is available only for Acanthocephalus ranae, a species that solely relies on the proboscis to attach. Here we compare body morphology and muscle arrangement in 13 species of Corynosoma, which use their spiny body as a fundamental holdfast. A basic performance analysis using live cystacanths of two representative species is also provided.…
Vocal function following laser and conventional surgery of small malignant vocal fold tumours
1996
AbstractIn the disecribed study, 26 patients after conventional, and 27 patients after laser cordectomy were examined six months or more after the operation. Videolarybogstroboscopy revealed that patients after laser cordectomy more often phonate on a purely glottic level (81 per cent) in comparison to patienbts after conventional cordectomy (19 per cent). Webs were more frequent and more extended after conventional cordectomy compared to endoscopic laser surgery. The maximal phonation time showed a very wide range with a mean value of 9 to 10 sec; there was no statistical difference between the groups of patients. Using yanagihara's classification of sonograms, a better voice quality was m…
High-Speed Imaging Analysis of Register Transitions in Classically and Jazz-Trained Male Voices
2014
<b><i>Background:</i></b> Little data are available concerning register functions in different styles of singing such as classically or jazz-trained voices. Differences between registers seem to be much more audible in jazz singing than classical singing, and so we hypothesized that classically trained singers exhibit a smoother register transition, stemming from more regular vocal fold oscillation patterns. <b><i>Methods:</i></b> High-speed digital imaging (HSDI) was used for 19 male singers (10 jazz-trained singers, 9 classically trained) who performed a glissando from modal to falsetto register across the register transition. Vocal fold osc…
Mujer, poder político y democracia paritaria. “Mujer y representación política institucional en la Comunidad Valenciana. 1977-1995. 2 parte.
2014
Mujer, poder político y democracia paritaria. “Mujer y representación política institucional en la Comunidad Valenciana. 1977-1995. 2 parte. En esta segunda parte se recogen las mujeres que han formado parte de la Administración Local (alcaldesas, diputadas provinciales y FVMP), en los sindicatos, asi como en otras instituciones: Consell Valencià de Cultura, Consejo de Radiotelevisión Valenciana, Sindicatura de Agravios, Academia Valenciana de la Lengua, universidades, direcciones de partidos políticos, y otras organizaciones de la Comunidad Valenciana. “Mujer y representación política institucional en la Comunidad Valenciana. 1977-1995. Diputadas, ministras y cargos institucionales” es la …