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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Descriptive assessment and functional analysis of problem behaviour among individuals with dementia

Craig, Bethany 21 April 2016 (has links)
Functional analysis is a method of behavioural assessment used to determine the environmental variables maintaining a specific behaviour. While functional analysis is often used with individuals with developmental and intellectual disabilities, problem behaviours in people with dementia are rarely assessed using functional analysis methodology. The purpose of the present study was to conduct descriptive and functional analyses of problem behaviours among individuals with dementia to determine: (a) if a descriptive assessment would identify a function of the challenging behaviour assessed; (b) the extent to which stimuli identified in the descriptive assessment were needed to conduct a functional analysis; and (c) if a standard functional analysis is an effective assessment method for this population. The participants were two individuals with dementia who exhibited inappropriate vocalizations, consisting of swearing and delusional speech. For both participants, the results of the descriptive assessments suggested that the function of the behaviour was positive reinforcement in the form of attention from staff members. The findings of the descriptive analyses were confirmed in the functional analyses. The results suggest that a functional analysis informed by a descriptive analysis can identify the function of problem behaviour in individuals with dementia in a residential setting. / May 2016
12

Profiles of Early and Later Vocalizations in Children with Cleft Lip and/or Palate and Children without Clefts

Scherer, Nancy J., Williams, A. Lynn, Kalbfleisch, John 01 January 1999 (has links)
No description available.
13

Vocalizations in the Grey Butcherbird Cracticus Torquatus with Emphasis on Structure in Male Breeding Song: Implications for the Function and Evolution of Song from a Study of a Southern Hemisphere Species.

Johnson, Gayle, n/a January 2003 (has links)
An undue focus on Temperate Zone oscines (songbirds or passerines) has led to a geographical bias in interpretation of song frmnction and evolution. This bias led initially to relatively simplistic theories of the ftmnction of bird song with vocalizations divided into 'songs' and 'calls'. Songs were complex, learned vocalizations, given by males in the breeding season, thnctioning in territory defence and mate attraction and stimulation. Calls, on the other hand, were simple innate vocalizations serving more immediate needs such as begging for food and raising an alarm. Female song, where it occurred, was considered an aberration. Further studies suggested that complex songs were associated with mate attraction functions while simpler songs were associated with territory defence. However it became apparent that the distinction between songs and calls was not nearly so clear-cut and the supposed connection between complexity and function in song was questioned. Moreover it was realised that female song could not be dismissed as a mere aberration. Another problem was the ftmnction of the dawn chorus, where research had failed to find a consistent, all-encompassing explanation. Since most studies had been done on Northern Hemisphere songbirds, it was becoming clear that the geographical focus needed to be broadened. The life histories of Northern Hemisphere TemperateZone songbirds are very different from those in many other regions. In contrast to the situation in this zone, maintenance of year-round territory, territory defence by both male and female, life-long social monogamy and extensive female vocalization are widespread in tropical, subtropical and Southern Hemisphere regions. Recently it has been suggested that more intensive studies of vocalizations in these regions might help clariQi some of these issues and consequently an endemic Australian passerine was chosen for the current study. The study focused on the vocalizationsof the grey butcherbird Cracticus torquatus Artamidae, which displays the life history features described above. The main study population was located in the Brisbane suburbs of Rainworth and Bardon. Additional data were gathered from other Brisbane suburbs and bushland sites within the city and at Lake Broadwater near Dalby, Queensland. Vocalizations were initially recorded electronically and analysed using Canary sound editing program. Vocalization data were supplemented using an aural recording method, which was independently checked for reliability. Behavioural data including posture during vocalizations and interactions with other birds were also gathered. Initial investigationsrevealed the existence of two main categories of vocalizations - those given by the family group during the day, all year round and those given at dawn by males during the breeding season. For the focal study populations, group vocalizations were studied throughout the year over several years, however the song given at dawn by males during the breeding season proved to be quite complex and three birds from three territories in the main study area were chosen as case studies. Recordings were made of the vocalizations of the three case study birds over three breeding seasons. Starting and fmishing times (with respect to civil twilight) were recorded in order to determine both changes in song bout duration and starting time throughout the breeding season. Additional birds from the same area, from the other Brisbane suburbs and from the bushland sites were studied to check the validity of conclusions drawn from the case studies. The results of the investigations revealed a vocalization structure that contrasted strongly with the simple picture of bird song drawn from study ofNorthernHemisphere Temperate Zone passerines. The vocalizations given during the day, often referred to as the 'song' of this species, were very different from the early dawn song given by the male during the breeding season. This latter appeared to be song sensu stricto according to the paradigms developed for Northern Hemisphere birds. The thytime vocalizations, however, fitted neither the classic definition of 'song' nor the classic definition of 'call'. This relatively long-term study revealed different starting time patterns and periodicity for thy vocalizations and male breeding season song. Day vocalizations commenced at a fairly constant time with respect to civil twilight throughoutthe year but breeding season song started progressively earlier from the beginning through to the middle of the season then progressively later till the end of the season. Relative finishing time of breeding song however remained constant so that the duration of breeding season song gradually increased then decreased paralleling the change in starting times. A consequence of the two distinct classes of vocalizations was that there were essentially two distinct 'dawn choruses'. One, consisting of group vocals, was sung all year round; the other was given by males singing 'breeding season' song. Since there was no reason the expect that a single function would necessarily be ascribed to both choruses, this raised the possibility that some of the confusion surrounding the ftinction and nature of the 'dawn chorus' originated from a failure to recognize the existence of two such choruses. Variation in time and space showed ifirther differences between the two vocalization classes. The breeding song of each male was distinctly different from that of his neighbours and there was a marked change in the repertoire of any individual from one year to the next. In marked contrast, daytime vocalization repertoires of neighbouring groups were virtually indistinguishable and changed little from year to year. These findings, together with information from recent literature, suggested that the two song classes had a different ontogeny, function and possibly evolution. It was proposed that territory declaration was the function of dawn singing by grey butcherbird family groups but that the function most consistent with adult male dawn song was attraction of females for extra-pair copulations. It was suggested that chorusing itself was to some extent an accidental by-product of the advantage to the individual or group of singing at dawn although a recently proposed function, the social dynamics function, could not be ruled out. Further differences from the Northern Hemisphere situation were detected in subsong. First, subsong was given by birds in their first year and also by adult males. The finding of subsong in adult males was not without precedent as it has been documented previously for a small number of passerines, especially those that change repertoire from year to year. Subsong in young (first year) birds, however, was unusual in that birds practised in small groups rather than in the complete isolation usually associated with subsong. Moreover they did not practise adult male song but instead practised group daytime vocalizations. It was suggested that it was important for birds to learn to sing in company for the important task of group territory defence. Further investigation of the literature and observations during the present study revealed similar vocalization classes and behaviours in other members of the Artamidae and other endemic Australasian taxa. These literature investigations also revealed that the possession two song vocalization classes was quite widespread although they tended to be restricted (but not exclusive) to males rather than found in males and females. These findings led to furtherresearch into the significanceofAustraliain the evolution of songbirds, the role of co-operative breeding in Australianpasserines, and finally to an hypothesis for a possible origin of male bird song. It is suggested that male song arose in a social environment where the male and female were in frequent vocal communication. If the tendency to seek extra-pair copulations (EPCs) and female choice had already been incorporated into the suite of passerine behaviours, it would be necessary to avoid the mate during such activities and the male would need to advertise with a signal distinct from group vocalizations. Early dawn, with poor light conditions, could be a favourable time for these activities. Thus it is proposed that the ancestral condition was with all group members singing most vocalisations, the intermediate situation was similar to that in the grey butcherbird and the 'advanced' condition was where female and other group member vocalizations (other than calls) have dropped out and only male song remains.
14

Acoustic Monitoring of Scotian Shelf Northern Bottlenose Whales (Hyperoodon ampullatus)

Moors, Hilary B. 26 June 2012 (has links)
An important step for protecting Endangered species is the identification of critical habitat. This can be especially challenging for deep ocean species. Northern bottlenose whales (Hyperoodon ampullatus) are deep-diving beaked whales of the North Atlantic. A population of this species occurs along the edge of the Scotian Shelf primarily in three submarine canyons that have been identified as critical habitat for the population: the Gully (the largest submarine canyon off eastern North America), Shortland Canyon and Haldimand Canyon. The Scotian Shelf population is considered Endangered mainly due to its small numbers and the anthropogenic threats it faces. The primary objective of my research was to further identify critical habitat of the population using passive acoustic monitoring, increasing knowledge of how the whales use the canyons and adjacent areas throughout the year. A review of the literature on cetacean associations with submarine canyons indicates that various mechanisms may act to attract cetaceans to these features. While many different species occur in canyons globally, they appear to be particularly important habitat for beaked whales. I developed an automated click detection algorithm customized for detecting northern bottlenose whale echolocation clicks, and long-term acoustic recordings were analyzed to examine the presence and relative abundance of northern bottlenose whales on the Scotian Slope over various spatial and temporal scales. The whales occurred in the area consistently throughout the year and all three canyons, as well as the area between canyons, appeared to be important foraging grounds for the population. The whales displayed diurnal foraging patterns. I also investigated niche separation between northern bottlenose whales and sperm whales (Physeter macrocephalus), another deep diving species. The presence of the two species was positively correlated over all spatial and temporal scales examined. These results indicate that areas within and adjacent to the Gully are important foraging grounds for northern bottlenose whales throughout the year. Furthermore, in addition to the canyons themselves, the shelf-edge areas between the Gully, Shortland and Haldimand canyons may constitute critical habitat for the whales. This research will be used to inform management measures relevant to the protection and recovery of this Endangered population.
15

Intraspecific Comparison of Vocalizations of the Florida Manatee (Trichechus manatus latirostris) on the East and West Coast of Florida

Brady, Beth A. 05 December 2011 (has links)
Photo-identification and telemetry studies have reported limited instances in which Florida manatees (Trichechus manatus latirostris) traversed the coastline of Florida. Manatee calls were recorded from four different locations in Florida. Using a single hydrophone, calls were recorded at two sites on the east coast and two sites on the west coast of Florida. These locations were representative of the four manatee management zones adopted by the Florida Fish and Wildlife Conservation Commission and the United States Geological Service. These include the Northwest, Southwest, Atlantic and Upper St. John’s River regions. Seven hundred calls from each site were selected for analysis to further quantify call parameters and evaluate differences within and across geographical locations. Fundamental and dominant frequencies, call duration, number of harmonics, and the percentage of frequency modulation, were measured, in addition to the first and third quartile frequency, energy, interquartile bandwidths. Spectrograms and statistical differences in frequency modulated vocalizations (one-way anova, p <0.0001) were used to classify calls into six categories; whistles, squeaks, high squeaks, squeak-squeals, chirps and squeals. (1) Whistles are narrow tonal calls with no frequency modulation. The frequency range for these calls is 1800 – 5000 Hz and a duration of 0.080 – 0.382 s. (2) Squeaks are more complex frequency modulated calls with 2 - 4 harmonics even at low intensities. They have a duration of 0.052 – 0.681 s and a frequency range of 562.1 – 10,312.5 Hz. (3) Squeals have no frequency modulation, are wideband signals, have a duration of 0.077 – 0.562 s and a frequency range of 468.4 – 6656.8 Hz. (4) Squeak-squeals have characteristics of squeaks and squeals. They may or may not have frequency modulation, have a duration of 0.090 – 0.612 s and a frequency range of 750.1 – 8625.5 Hz. High squeaks are strongly modulated, have a duration of 0.131 – 0.236 s, and a frequency range of 1,300.2 – 10,628.8 Hz. Chirps are characterized by having two or three dominant energy bands that are separated by short gaps, have frequency modulation, a duration of 0.031 – 0.283 s, and a frequency range of 1,265.3 – 6937.5 Hz. Since it was unknown which manatee was eliciting the call, group means of the variables center fundamental frequency and first and third quartile frequency where used to analyze differences or similarities within and between coastlines. A T test was used to compare means at a 95% confidence interval. Spectrograms of the categorized calls were analyzed within and between coastlines. Results from t-tests suggest there are no differences in calls for the variables studied within and between east and west coast populations of the Florida manatee (all p values > 0.05). Correlation of spectrographic images suggests there is a high degree of similarity among categorized calls and calls seem to differ mostly in call contour.
16

Characterization of Foxp2 functions in the mouse cortex / Caractérisation des fonctions du facteur de transcription Foxp2 dans le cortex murin

Medvedeva, Vera 17 June 2015 (has links)
Des mutations du gène Foxp2 constituent le premier exemple connu de cause monogénique de troubles de la parole et du langage. Les individus atteints souffrent de difficultés d’articulation (dyspraxie verbale) mais aussi de perturbations du langage parlé et écrit, ce qui indique la présence d’un trouble cognitif. La séquence et la distribution d’expression de ce gène sont remarquablement conservées parmi les vertébrés.Cette thèse visait principalement à identifier les fonctions du facteur de transcription Foxp2 dans le cortex en caractérisant un modèle murin conditionnel dans lequel ce gène a été spécifiquement inactivé dans les neurones corticaux. Ce modèle murin permet ainsi d’étudier certains aspects des pathologies liées à Foxp2, notamment les aspects de communication et les comportements sociaux. En parallèle, j’ai entrepris, sur un autre modèle murin, des études moléculaires afin d’identifier les gènes perturbés par la réduction de l’expression de Foxp2 dans le cortex. L‘ensemble des résultats présentés suggère que l’inactivation de Foxp2 dans le cortex conduit à des défauts subtils des comportements sociaux sans modification majeure de la morphologie du cortex ou des neurones. Je montre en particulier que les souris mutées présentent des changements de vocalisation ultrasonique lors d’interactions entre mâles et femelles. Par ailleurs, en utilisant un modèle de souris hétérozygote pour une mutation dans Foxp2, j’ai identifié parmi les gènes dérégulés le gène Mint2 déjà impliqué chez l’homme dans l’autisme.En conclusion, ces résultats permettront de mieux comprendre le rôle de Foxp2 au niveau cortical chez les souris pour décrypter les mécanismes moléculaires qui ont été sélectionnés chez l’homme pendant l'évolution de la parole et du langage. / Genetic disruptions of the forkhead box transcription factor FOXP2 in humans cause a severe autosomal-dominant speech and language disorder. FOXP2 expression pattern and genomic structure are highly conserved in distant vertebrates. We hypothesized that this conservation may allow the use of animal models to identify Foxp2 dependent neuronal circuits and molecular networks involved in social behaviors. Therefore I began characterizing Foxp2 functions in the mouse cortex in conventional heterozygous (Foxp2+/-) and conditional (cortex specific) Foxp2 homozygous mutant mice (Nex-Cre; Foxp2lox/lox). Initial characterization of Nex-Cre; Foxp2lox/lox mice revealed no gross alterations in morphological architecture, postnatal development and basic adult behaviors. However, behavioral profiling of Nex-Cre; Foxp2lox/lox mice demonstrated deficiency in specific social behaviors such as approach behavior towards conspecifics and responses of WT interaction partners. Furthermore, Nex-Cre; Foxp2lox/lox mice showed alterations in specific acoustical parameters of ultrasonic vocalizations (USV), and the type of modulation differed in function of social context. Gene expression profiling of Foxp2-positive cortical pyramidal neurons in Foxp2+/- mice revealed the dysregulation of Mint2, a gene involved in approach behavior in mice and autism spectrum disorder in humans. This result was further validated in cortex-specific Foxp2 mutant mice The results deliver first insights into cortical Foxp2 dependent functions in mouse social behaviors. This provides a rational basis for further mechanistic studies of the ancestral functions of cortical Foxp2 that may have been recruited during speech and language evolution.
17

Recording and automatic detection of African elephant (Loxodonta africana) infrasonic rumbles

Venter, Petrus Jacobus 01 October 2008 (has links)
The value of studying elephant vocalizations lies in the abundant information that can be retrieved from it. Recordings of elephant rumbles can be used by researchers to determine the size and composition of the herd, the sexual state, as well as the emotional condition of an elephant. It is a difficult task for researchers to obtain large volumes of continuous recordings of elephant vocalizations. Recordings are normally analysed manually to identify the location of rumbles via the tedious and time consuming methods of sped up listening and the visual evaluation of spectrograms. The application of speech processing on elephant vocalizations is a highly unexploited resource. The aim of this study was to contribute to the current body of knowledge and resources of elephant research by developing a tool for recording high volumes of continuous acoustic data in harsh natural conditions as well as examining the possibilities of applying human speech processing techniques to elephant rumbles to achieve automatic detection of these rumbles in recordings. The recording tool was designed and implemented as an elephant recording collar that has an onboard data storage capacity of 128 gigabytes, enough memory to record sound data continuously for a period of nine months. Data is stored in the wave file format and the device has the ability to navigate and control the FAT32 file system so that the files can be read and downloaded to a personal computer. The collar also has the ability to stamp sound files with the time and date, ambient temperature and GPS coordinates. Several different options for microphone placement and protection have been tested experimentally to find an acceptable solution. A relevant voice activity detection algorithm was chosen as a base for the automatic detection of infrasonic elephant rumbles. The chosen algorithm is based on a robust pitch determination algorithm that has been experimentally verified to function correctly under a signal-to-noise ratio as low as -8 dB when more than four harmonic structures exist in a sound. The algorithm was modified to be used for elephant rumbles and was tested with previously recorded elephant vocalization data. The results obtained suggest that the algorithm can accurately detect elephant rumbles from recordings. The number of false alarms and undetected calls increase when recordings are contaminated with unwanted noise that contains harmonic structures or when the harmonic nature of a rumble is lost. Data obtained from the recording collar is less prone to being contaminated than far field recordings and the automatic detection algorithm should provide an accurate tool for detecting any rumbles that appear in the recordings. / Dissertation (MEng)--University of Pretoria, 2008. / Electrical, Electronic and Computer Engineering / unrestricted
18

Oceanography and underwater acoustics in Resolute Bay, Nunavut: 2012-2015

O'Neill, Caitlin 12 July 2016 (has links)
Resolute Bay, a remote Arctic bay opening into Parry Channel, in the Canadian Arctic Archipelago, hosts diverse populations of marine mammals and fish at various times each year. These animals migrate through the bay following patterns linked to food availability and oceanographic conditions; however, these patterns are not well understood. The focus of this study was to measure the oceanographic properties of the waters in and around Resolute Bay and to record underwater sounds to obtain marine mammal temporal patterns and ambient sound levels. Results showed the water properties in Resolute Bay differed from the waters outside of the bay. Dissolved oxygen saturation levels in Resolute Bay decreased during ice-covered times, with lowest levels between May and July. Dissolved oxygen was replenished after the ice left the bay. Sudden changes in salinity, temperature, and dissolved oxygen were observed in Resolute Bay when outside waters entered. Mean third-octave band sound pressure levels were 85.3 dB re 1 μPa during high ice concentration, and 95.6 dB re 1 μPa during ice-free and freeze-up periods, and reached a maximum of 145.3 dB re 1 μPa when vessels were present. Belugas (Delphinapterus leucas) and narwhals (Monodon monocero) were only present in periods of low ice concentration, while bearded seals (Erignathus barbatus) and ringed seals (Pusa hispida) remained throughout the entire year. / Graduate / 2018-07-01
19

BEHAVIORAL AND NEUROMODULATORY RESPONSES TO EMOTIONAL VOCALIZATIONS IN MICE

Ghasemahmad, Zahra 19 August 2020 (has links)
No description available.
20

Uising vocalizations to understand the classification of Mirafra javanica and Mirafra cantillans

M'Bark, Alexia January 2023 (has links)
The taxonomic status of Mirafra cantillans and M. javanica has undergone revision severaltimes: sometimes considered a single species, but most often considered two separate species.Recent mitochondrial (Alström et al. 2013) and multilocus (Alström et al. 2023) studies havecontributed to this dynamic, with the mitochondrial data suggesting that there is only onespecies, while the genomic data is more indicative of two species. Despite this, vocalizations,a known tool for identifying avian species and an important source of data in taxonomicstudies, have not yet been analyzed for this species complex. This study analyzed recordingsof vocalizations of M. cantillans and M. javanica (here treated as two species) to provide newinsight into their taxonomy. Based on over 150 recordings from across the range (westernAfrica to eastern Australia), I used a combination of numerical measurements, auditory, andvisual data to evaluate their taxonomy. Overlap and consistencies between the patterns of thesongs was found throughout the entire range of the complex, with the most vocally distinctgeographical population identified being from India, though there was significant overlapbetween all populations. Mimicry, continuous songs, and block patterning were found to bepresent throughout the majority of the populations from different geographical regions. Threegeographically separate song types were identified (Africa to Arabia, India, and SoutheastAsia to Australia).

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