Repositório RCAAP
Analysis of whistles produced by the Tucuxi Dolphin Sotalia fluviatilis from Sepetiba Bay, Brazil
From July 2001 to June 2002, we recorded a total of 2h55min of Tucuxi Dolphin Sotalia fluviatilis vocalizations from Sepetiba Bay, Brazil (22º35'S-44º03'W). A total of 3350 whistles were analyzed quantitative and qualitatively and were divided into 124 types, by visual inspection of sonograms. The following parameters were measured: Initial Frequency, Final Frequency, Minimum Frequency, Maximum Frequency, Duration, Number of Inflections, Frequency at the Inflection Points, Frequency at 1/2, 1/4, and 3/4 of whistle duration, Presence of Frequency Modulation and Harmonics. Ascending type whistles (N=2719) were most common, representing 82% of the total. Dolphin behavior and average group size observed during recording influenced the whistle's quantitative and qualitative parameters. The results demonstrate the great diversity of whistles emitted and indicate a functional role of these vocalizations during the observed behaviors.
2004
Erber,Claudia Simão,Sheila M.
Differences in the whistle characteristics and repertoire of Bottlenose and Spinner Dolphins
Several methods have been used to compare the whistles produced by dolphins. The two methods used in this study are: (1) a classification of whistle contours in six categories (i.e. constant frequency, upsweep, downsweep, concave, convex, and sine) and (2) the extraction of frequency and time parameters from each whistle contour. Bottlenose Dolphin Tursiops truncatus whistles are described in the same way when comparing whistle contour distributions in each of the six categories and whistle frequency and time parameters using Discriminant Function Analysis. For Spinner Dolphin Stenella longirostris whistles, each method describes whistles differently. Several facts may explain these differences in describing dolphin whistles, such as a greater fluidity of Spinner Dolphin groups when compared to Bottlenose Dolphin groups, greater geographic variation in the whistles of Bottlenose Dolphins than in those of Spinner Dolphins, an average beginning frequency 16% lower than the average ending frequency in Spinner Dolphin whistles compared to a varied relationship for Bottlenose Dolphins, and stricter criteria used to define whistle contour categories in the study of Spinner Dolphin whistles than in the Bottlenose Dolphin whistle study.
2004
Bazúa-Durán,Carmen
Long-distance calls in Neotropical primates
Long-distance calls are widespread among primates. Several studies concentrate on such calls in just one or in few species, while few studies have treated more general trends within the order. The common features that usually characterize these vocalizations are related to long-distance propagation of sounds. The proposed functions of primate long-distance calls can be divided into extragroup and intragroup ones. Extragroup functions relate to mate defense, mate attraction or resource defense, while intragroup functions involve group coordination or alarm. Among Neotropical primates, several species perform long-distance calls that seem more related to intragroup coordination, markedly in atelines. Callitrichids present long-distance calls that are employed both in intragroup coordination and intergroup contests or spacing. Examples of extragroup directed long-distance calls are the duets of titi monkeys and the roars and barks of howler monkeys. Considerable complexity and gradation exist in the long-distance call repertoires of some Neotropical primates, and female long-distance calls are probably more important in non-duetting species than usually thought. Future research must focus on larger trends in the evolution of primate long-distance calls, including the phylogeny of calling repertoires and the relationships between form and function in these signals.
2004
Oliveira,Dilmar A.G. Ades,César
Vocal sequential exchanges and intragroup spacing in the Northern Muriqui Brachyteles arachnoides hypoxanthus
Sequential exchanges of vocalizations (staccatos and neighs) emitted by Northern Muriquis Brachyteles arachnoides hypoxanthus were recorded at the Biological Station of Caratinga, Minas Gerais State, Brazil. Staccatos and neighs containing larger proportion of short elements were preferentially produced during short-range exchanges; neighs, produced by a larger number of participants, were typical of long-range exchanges. Staccatos emitted by animals feeding in a dispersed manner contained a larger proportion of tonal elements than those emitted by muriquis feeding in a cohesive manner. Sequential exchanges seem thus to be constituted by two inter-related subsystems of calls that aid muriquis to coordinate intragroup spacing, despite the poor visibility of the habitat.
2004
Mendes,Francisco D.C. Ades,César
Bioacoustics of human whistled languages: an alternative approach to the cognitive processes of language
Whistled languages are a valuable heritage of human culture. This paper gives a first survey about a new multidisciplinary approach to these languages. Previous studies on whistled equivalents of languages have already documented that they can provide significant information about the role of rhythm and melody in language. To substantiate this, most whistles are represented by modulations of frequency, centered around 2000 Hz (±1000 Hz) and often reach a loudness of about 130 dB (measured at 1m from the source). Their transmission range can reach up to 10 km (as verified in La Gomera, Canary Island), and the messages can remain understandable, even if the signal is deteriorated. In some cultures the use of whistled language is associated with some "talking musical instruments" (e.g. flutes, guitars, harps, gongs, drums, khens). Finally, whistles as a means of conveying information have some analogues in the animal kingdom (e.g. some birds, cetaceans, primates), providing opportunities to compare the acoustic characteristics of the respective signals. With such properties as a reference, the project reported here has two major tasks: to further elucidate the many facets of whistled language and, above all, help to immediately stop the process of its gradual disappearance.
2004
Meyer,Julien
Communication by unvoiced speech: the role of whispering
Most studies on whispering deal with its production and perception, neglecting its communicative role. I have focused on this, especially some social and psychobiological objectives. I have combined a general inquiry into the use of unvoiced speech with stimulus-response experiments on particular signal properties. (1) Analyses of answers to queries revealed that judgments about whispering depend on the social contexts. In the private domain it plays a clearly positive role, but in the public domain it is more problematical. Two causative factors were identified as relevant: (a) an 'ingroup' function of whispering which could induce negative 'outgroup' effects in co-listeners, and (b) a psychobiological component of whispering which could affect the auditory vigilance of co-listeners who were not addressed personally by the signaling, but often wanted to understand a whispered message. (2) Analyses of experimental data confirmed the relevance of these factors. Additionally, they showed that unvoiced speech has a limited transmission range, and is easily masked by background noise. Taken together, the results suggest that whispering is explained best as a close-distance signal adapted for private use among partners.
2004
Cirillo,Jasmin
Bits and q-bits as versatility measures
Using Shannon information theory is a common strategy to measure any kind of variability in a signal or phenomenon. Some methods were developed to adapt information entropy measures to bird song data trying to emphasize its versatility aspect. This classical approach, using the concept of bit, produces interesting results. Now, the original idea developed in this paper is to use the quantum information theory and the quantum bit (q-bit) concept in order to provide a more complete vision of the experimental results.
2004
Piqueira,José R.C.
Species richness and relative abundance of birds in natural and anthropogenic fragments of Brazilian Atlantic forest
Bird communities were studied in two types of fragmented habitat of Atlantic forest in the State of Paraná, southern Brazil; one consisted of forest fragments that were created as a result of human activities (forest remnants), the other consisted of a set of naturally occurring forest fragments (forest patches). Using quantitative data obtained by the point counts method in 3 forest patches and 3 forest remnants during one year, species richness and relative abundance were compared in those habitats, considering species groups according to their general feeding habits. Insectivores, omnivores, and frugivores presented similar general tendencies in both habitats (decrease of species number with decreasing size and increasing isolation of forest fragment). However, these tendencies were different, when considering the relative abundance data: the trunk insectivores presented the highest value in the smallest patch while the lowest relative abundance was in the smallest remnant. In the naturally fragmented landscape, time permitted that the loss of some species of trunk insectivores be compensated for the increase in abundance of other species. In contrast, the remnants essentially represented newly formed islands that are not yet at equilibrium and where future species losses would make them similar to the patches.
2004
Anjos,Luiz dos
Automated bioacoustic identification of species
Research into the automated identification of animals by bioacoustics is becoming more widespread mainly due to difficulties in carrying out manual surveys. This paper describes automated recognition of insects (Orthoptera) using time domain signal coding and artificial neural networks. Results of field recordings made in the UK in 2002 are presented which show that it is possible to accurately recognize 4 British Orthoptera species in natural conditions under high levels of interference. Work is under way to increase the number of species recognized.
2004
Chesmore,David
Identification of Tibicen cicada species by a Principal Components Analysis of their songs
Specific identification of three Tibicen cicadas, T. japonicus, T. flammatus and T. bihamatus, by their chirping sounds was carried out using Principal Components Analysis (PCA). High quality recordings of each species were used as the standards. The peak and mean frequencies and the pulse rate were used as the variables. Out of 12 samples recorded in the fields one fell in the vicinity of T. japonicus and all other were positioned near T. bihamatus. Then the cluster analysis of the PCA scores clearly separated each species and allocated the samples in the same way.
2004
Ohya,Eiji
Application of automated bioacoustic identification in environmental education and assessment
Developments in electronics and computer science have led to the introduction of an automated bioacoustic identification device used to resolve commonly encountered problems in the identification of animal species in the field. This technology aids our auditory observations, and also improves the quality of biological surveys and environmental monitoring. In this paper the future roles and possibilities of bioacoustics are discussed, providing some examples from the realm of environmental education and monitoring that focus on the use of nature sounds.
2004
Oba,Teruyo
Compact and user-friendly ultrasound acquisition systems optimized for field recording
A compact and rugged hardware interface for laptop-based ultrasound recording in the field has been developed. The versatile devices overcome the limitations and drawbacks of previously available solutions. The accompanying recording software enables flexible hard disk recording for both manual and automated operation.
2004
Specht,Raimund
Natural sound archives: past, present and future
Recordings of wild animals were first made in the Palearctic in 1900, in the Nearctic in 1929, in Antarctica in 1934, in Asia in 1937, and in the Neotropics in the 1940s. However, systematic collecting did not begin until the 1950s. Collections of animal sound recordings serve many uses in education, entertainment, science and nature conservation. In recent years, technological developments have transformed the ways in which sounds can be sampled, stored and accessed. Now the largest collections between them hold altogether around 0.5 million recordings with their associated data. The functioning of a major archive will be described with reference to the British Library Sound Archive. Preserving large collections for the long term is a primary concern in the digital age. While digitization and digital preservation has many advantages over analogue methods, the rate of technology change and lack of standardization are a serious problem for theworld's major audio archives. Another challenge is to make collections more easily and widely accessible via electronic networks. On-line catalogues and access to the actual sounds via the internet are already available for some collections. Case studies describing the establishment and functioning of sound libraries inMexico, Colombia and Brazil are given in individually authored sections in an Appendix.
2004
Ranft,Richard
A remark on soliton equation of mean curvature flow
In this note, we consider self-similar immersions of the mean curvature flow and show that a graph solution of the soliton equation, provided it has bounded derivative, converges smoothly to a function which has some special properties (see Theorem 1.1).
2004
Ma,Li Yang,Yang
Finite approximate controllability for semilinear heat equations in noncylindrical domains
We investigate finite approximate controllability for semilinear heat equation in noncylindrical domains. First we study the linearized problem and then by an application of the fixed point result of Leray-Schauder we obtain the finite approximate controllability for the semilinear state equation.
2004
Menezes,Silvano B. de Limaco,Juan Medeiros,Luis A.
Hypersurfaces with constant mean curvature and two principal curvatures in n+1
In this paper we consider compact oriented hypersurfaces M with constant mean curvature and two principal curvatures immersed in the Euclidean sphere. In the minimal case, Perdomo (Perdomo 2004) andWang (Wang 2003) obtained an integral inequality involving the square of the norm of the second fundamental form of M, where equality holds only if M is the Clifford torus. In this paper, using the traceless second fundamental form of M, we extend the above integral formula to hypersurfaces with constant mean curvature and give a new characterization of the H(r)-torus.
2004
Alías,Luis J. Almeida,Sebastião C. de Brasil Jr.,Aldir
Plumbagin quantification in roots of Plumbago scandens L. obtained by different extraction techniques
The Plumbago genus belongs to the Plumbaginaceae family and it is known due to its variety of biological uses, most of them attributed to the presence of naphthoquinones. Plumbagin is a naturally occurring naphthoquinone that can be obtained from roots of Plumbago scandens L. In order to find out the better technique for plumbagin extraction, were applied: static maceration, dynamic maceration, with assistance of ultrasonic waves and in Soxhlet apparatus. Four compounds were qualitatively detected in all extracts: the naphthoquinones plumbagin and epi-isoshinanolone, palmitic acid and sitosterol. Plumbagin was always the major component in all analyzed extracts and it was quantitatively determined by gas chromatograph coupled with mass spectrometer. Soxhlet was the most efficient extraction technique however, prolonged heating time promoted plumbagin degradation.
2004
Paiva,Selma R. de Lima,Lucilene A. Figueiredo,Maria Raquel Kaplan,Maria Auxiliadora C.
Chemical constituents from Vellozia graminifolia (Velloziaceae)
From the hexane and ethyl acetate extracts obtained from stems, roots and leaf sheaths of Vellozia graminifolia, a mixture of linear hydrocarbons, a mixture of pentacyclic triterpenes, five monoisoprenylated flavonoids and one labdane diterpene, (-)-ent-3beta-hydroxy-8(17)-labden-15-oic acid, were isolated. The linear hydrocarbons and minor triterpenes were identified in their corresponding mixtures by High Resolution Gas Chromatography (HRGC) and HRGC coupled to mass spectrometry. The major pentacyclic triterpenes and the diterpene were characterized by spectral data, including 2D NMR experiments, and chemical transformations.
2004
Branco,Alexsandro Pinto,Angelo C. Braz Filho,Raimundo
The T-cell anergy induced by Leishmania amazonensis antigens is related with defective antigen presentation and apoptosis
Leishmania amazonensis is the main agent of diffuse cutaneous leishmaniasis, a disease associated with anergic immune responses. In this study we show that the crude antigen of Leishmania amazonensis (LaAg) but not L. braziliensis promastigotes (LbAg) contains substances that suppress mitogenic and spontaneous proliferative responses of T cells. The suppressive substances in LaAg are thermoresistant (100ºC/1h) and partially dependent on protease activity. T cell anergy was not due to a decreased production of growth factors as it was not reverted by addition of exogenous IL-2, IL-4, IFN-gamma or IL-12. LaAg did not inhibit anti-CD3-induced T cell activation, suggesting that anergy was due to a defect in antigen presentation. It was also not due to cell necrosis, but was accompanied by expressive DNA fragmentation in lymph node cells, indicative of apoptosis. Although pre-incubation of macrophages with LaAg prevented their capacity to present antigens, this effect was not due to apoptosis of the former. These results suggest that the T cell anergy found in diffuse leishmaniasis may be the result of parasite antigen-driven apoptosis of those cells following defective antigen presentation.
2004
Pinheiro,Roberta O. Pinto,Eduardo F. Benedito,Alessandra B. Lopes,Ulisses G. Rossi-Bergmann,Bartira
Genes and chromosomes: control of development
The past decade has witnessed immense progress in research into the molecular basis behind the developmental regulation of genes. Sets of genes functioning under hierarchical control have been identified, evolutionary conserved systems of genes effecting the cell-to-cell transmission of transmembrane signals and assigned a central role in morphogenesis have been intensively studied; the concept of genomic regulatory networks coordinating expression of many genes has been introduced, to mention some of the major breakthroughs. It should be noted that the temporal and tissue-specific parameters of gene expression are correctly regulated in development only in the context of the chromosome and that they are to a great extent dependent on the position of the gene on the chromosome or the interphase nucleus. Moreover epigenetic inheritance of the gene states through successive cell generations has been conducted exclusively at the chromosome level by virtue of cell or chromosome memory. The ontogenetic memory is an inherent property of the chromosome and cis-regulation has a crucial role in its maintenance.
2004
Serov,Oleg Serova,Irina