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1.
Dr Samuel Johnson was noted by his friends to have almost constant tics and gesticulations, which startled those who met him for the first time. He also made noises and whistling sounds; he made repeated sounds and words and irregular or blowing respiratory noises. Further, he often carried out pronounced compulsive acts, such as touching posts, measuring his footsteps on leaving a room, and performing peculiar complex gestures and steps before crossing a threshold. His symptoms of (a) involuntary muscle jerking movements and complex motor acts, (b) involuntary vocalisation, and (c) compulsive actions constitute the symptom complex of Gilles de la Tourette syndrome (Tourette''s syndrome), from which Johnson suffered most of his life. This syndrome is of increasing interest recently because it responds to haloperidol, and because there are new insights into a possible biochemical basis for the tics, vocalisations, and compulsions.  相似文献   

2.
Inbreeding is sometimes tolerated in species occupying patchy, unpredictable habitats, when it becomes too costly to outbreed. Although traits leading to inbreeding depression may be selected against, the accumulation of deleterious alleles from constant inbreeding might promote outbreeding. Littledale’s whistling rat Parotomys littledalei occupies patchy habitats in arid western South Africa, and inbreeds in captivity without suffering inbreeding depression. We tested whether female whistling rats make different mate choice decisions based on their inbreeding status, by providing inbred and outbred females with male odours in four pairwise combinations: unrelated outbred (r = 0) versus either familiar littermate sibling (r = 0.5), half-sibling (r = 0.25), first cousin (r = 0.125), or unrelated inbred (r = 0). Inbred females generally preferred unrelated males, but did not show a preference between unrelated males and first cousins. In contrast, outbred females did not generally show a preference, but preferred first cousins to unrelated males. In breeding trials, reproductive success (output and viability of young) of outbred females paired with unrelated or related males was equally high, whereas inbred females suffered reduced reproductive success when paired with closely-related males. Our results indicate that the inbreeding status of female whistling rats influences their decision to outbreed or inbreed, which might influence their fitness. While outbred whistling rats do not suffer inbreeding depression, the costs of constant inbreeding could promote outbreeding by inbred females. We propose that the choice to inbreed or outbreed in female whistling rats depends on their inbreeding status and the genetic relatedness of available mates, with outbreeding more likely to occur unless unrelated mates are not available.  相似文献   

3.
In Brants' whistling rat, Parotomys brantsii, single animals inhabit unusually complex burrow systems containing several nest chambers. We investigated burrow use and examined the effect of ectoparasites on choice of alternative nest chambers by radiotelemetrically monitoring the nocturnal sleeping locations of individual whistling rats, before and after treating them to remove ectoparasites. Prior to treatment, animals used several different nest chambers within a single burrow, moving from one chamber to another every 1.6 d on average, and most individuals also slept in more than one burrow. Anti‐parasite treatment reduced the rate at which animals switched from one nest chamber to another within a burrow. Screening of a separate sample of animals for ectoparasites revealed that they were infested with fleas, mainly Xenopsylla eridos. We suggest that by switching periodically from one nest chamber to another, whistling rats reduce the rate at which ectoparasites, especially fleas, accumulate.  相似文献   

4.
By analyzing acoustic signals recorded from Sotalia in the Amazon River, its appears that phonation system use the same mechanism to produce click and monochromatic whistling, with a regular evolution between them.  相似文献   

5.
There are many large, easy‐to‐observe anseriform birds (ducks, geese, and swans) in northern Australia and New Guinea and they often gather in large numbers. Yet, the structure of their populations and their regional movements are poorly understood. Lack of understanding of population structure limits our capacity to understand source‐sink dynamics relevant to their conservation or assess risks associated with avian‐borne pathogens, in particular, avian influenza for which waterfowl are the main reservoir species. We set out to assess present‐day genetic connectivity between populations of two widely distributed waterfowl in the Australo‐Papuan tropics, magpie goose Anseranas semipalmata (Latham, 1798) and wandering whistling‐duck Dendrocygna arcuata (Horsfield, 1824). Microsatellite data were obtained from 237 magpie geese and 64 wandering whistling‐duck. Samples were collected across northern Australia, and at one site each in New Guinea and Timor Leste. In the wandering whistling‐duck, genetic diversity was significantly apportioned by region and sampling location. For this species, the best model of population structure was New Guinea as the source population for all other populations. One remarkable result for this species was genetic separation of two flocks sampled contemporaneously on Cape York Peninsula only a few kilometers apart. In contrast, evidence for population structure was much weaker in the magpie goose, and Cape York as the source population provided the best fit to the observed structure. The fine scale genetic structure observed in wandering whistling‐duck and magpie goose is consistent with earlier suggestions that the west‐coast of Cape York Peninsula is a flyway for Australo‐Papuan anseriforms between Australia and New Guinea across Torres Strait.  相似文献   

6.
We studied the effect of predation risk on grouping pattern and whistling behaviour in a free-ranging mouflonOvis aries Linnaeus, 1758 population in Sardinia. Direct observations were carried out from July 2005 to June 2007 (n groups=881,n mouflon=3477). In our study site, the rut occurred in October and November, when social sexual segregation disappeared, while lambing peaked in April. Groups with lambs (mean ± SE: female groups with lambs 4.98 ± 0.23, mixed groups 6.49 ± 0.29) were larger than male groups (2.01 ± 0.10) and female groups without lambs (2.77 ± 0.11), especially during the lambing season. This reflected the anti-predator tactics adopted by mothers so as to benefit from the dilution effect. Also male aggregations increased in size during the lambing season, as a consequence of the gradual decrease of rutting activities and consequently of male-male aggressiveness. Among the anti-predator tactics adopted by mouflon, whistling behaviour seemed to be a warning signal directed to predators and not to conspecifics. This was because whistling was shown by smaller aggregations only, regardless of group type, presence of lamb and habitat occupied. Smaller groups cannot profit from the dilution effect and therefore may be more motivated to signal the predator that it has been spotted.  相似文献   

7.
From 23 to 25 July 2002, 98-103 newly hatched black-bellied whistling ducks (Dendrocygna autumnalis) were observed alive at an inland saline lake (La Sal Vieja) in Willacy County, Texas (USA). Seventy-one (71%) died after showing signs indicative of sodium toxicity within 5 hr of entering the water; some died within minutes. Six carcasses were sent to the United States Geological Survey, National Wildlife Health Center (Madison, Wisconsin, USA) for analysis, and brain sodium levels of all ducklings were above 2,000 parts per million wet weight. More black-bellied whistling duck ducklings are likely to have been affected, but they were not observed after hatching.  相似文献   

8.
ABSTRACT

Here we present an acoustic approach for reliable sexing in four whistling duck species from the genus Dendrocygna and compare it with molecular and cloacal inspection techniques. In the four examined species, the White-faced Whistling Duck D. viduata, Fulvous Whistling Duck D. bicolor, Cuban Whistling Duck D. arborea and Red-billed Whistling Duck D. autumnalis, sexes are indistinguishable by appearance. However all the four species show strong sexual differences in the structure of their species-specific loud whistles. For 59 examined birds, an acoustic-based sexing showed 100% accordance to the DNA PCR analysis, while the cloacal inspection showed only 89.8% accuracy. The results demonstrate that acoustic sexing represents a feasible alternative to the two traditional methods as a noninvasive tool for the distant sexing of the four whistling duck species both in captivity and in the wild.  相似文献   

9.

Background

Estimates of prevalence of wheeze depend on questionnaires. However, wording of questions may vary between studies. We investigated effects of alternative wording on estimates of prevalence and severity of wheeze, and associations with risk factors.

Methods

White and South Asian children from a population-based cohort (UK) were randomly assigned to two groups and followed up at one, four and six years (1998, 2001, 2003). Parents were asked either if their child ever had “attacks of wheeze” (attack group, N=535), or “wheezing or whistling in the chest” (whistling group, N=2859). All other study aspects were identical, including questions about other respiratory symptoms.

Results

Prevalence of wheeze ever was lower in the attack group than in the whistling group for all surveys (32 vs. 40% in white children aged one year, p<0.001). Prevalence of other respiratory symptoms did not differ between groups. Wheeze tended to be more severe in the attack group. The strength of association with risk factors was comparable in the two groups.

Conclusions

The wording of questions on wheeze can affect estimates of prevalence, but has less impact on measured associations with risk factors. Question wording is a potential source of between-study-heterogeneity in meta-analyses.  相似文献   

10.
Wild-caught, immature black-bellied whistling ducks (Dendrocygna autumnalis) were inoculated with eastern equine encephalitis (EEE), St. Louis encephalitis (SLE), or western equine encephalitis (WEE) virus. Susceptibility, duration and titer of viremia, and antibody response to these arboviruses were determined. Birds from all inoculated groups became viremic. Higher virus titers occurred in the EEE group but overall mean titers were not significantly different among experimental groups. All birds inoculated with EEE and SLE viruses developed antibodies, and six of seven ducks receiving WEE virus were seropositive. All seropositive ducks had antibodies for at least 59 days, when the study was terminated. The EEE group had significantly more seropositive ducks during more days than the WEE and SLE groups. Geometric mean antibody titers were significantly smaller in the WEE group when compared to the EEE and SLE groups. Control ducks did not develop viremia or antibodies. Gross and histopathologic lesions compatible with viral encephalitis were absent in all of nine ducks necropsied. Black-bellied whistling ducks can develop low and short-term levels of viremia sufficient to infect mosquitoes, but probably cannot contribute significantly to the transmission of EEE and SLE. They may serve as good indicators of virus activity.  相似文献   

11.
The behavioural phenotype of women with Turner syndrome (X-monosomy, 45,X) is poorly understood, but includes reports of some social development anomalies. With this in mind, accuracy of direction of gaze detection was investigated in women with Turner syndrome. Two simple experimental tasks were used to test the prediction that the ability to ascertain gaze direction from face photographs showing small lateral angular gaze deviations would be impaired in this syndrome, compared with a control population of men and women. The prediction was confirmed and was found to affect both the detection of egocentric gaze from the eyes (''is the face looking at me?'') and the detection of allocentric gaze, where the eyes in a photographed face inspected one of a number of locations of attention (''where is she looking?''). We suggest that dosage-sensitive X-linked genes contribute to the development of gaze-monitoring abilities.  相似文献   

12.
Typically developing (TD) infants enhance their learning of spoken language by observing speakers’ mouth movements. Given the fact that word learning is seriously delayed in most children with neurodevelopmental disorders, we hypothesized that this delay partly results from differences in visual face scanning, e.g., focusing attention away from the mouth. To test this hypothesis, we used an eye tracker to measure visual attention in 95 infants and toddlers with Down syndrome (DS), fragile X syndrome (FXS), and Williams syndrome (WS), and compared their data to 25 chronological- and mental-age matched 16-month-old TD controls. We presented participants with two talking faces (one on each side of the screen) and a sound (/ga/). One face (the congruent face) mouthed the syllable that the participants could hear (i.e., /ga/), while the other face (the incongruent face) mouthed a different syllable (/ba/) from the one they could hear. As expected, we found that TD children with a relatively large vocabulary made more fixations to the mouth region of the incongruent face than elsewhere. However, toddlers with FXS or WS who had a relatively large receptive vocabulary made more fixations to the eyes (rather than the mouth) of the incongruent face. In DS, by contrast, fixations to the speaker’s overall face (rather than to her eyes or mouth) predicted vocabulary size. These findings suggest that, at some point in development, different processes or strategies relating to visual attention are involved in language acquisition in DS, FXS, and WS. This knowledge may help further explain why language is delayed in children with neurodevelopmental disorders. It also raises the possibility that syndrome-specific interventions should include an early focus on efficient face-scanning behaviour.  相似文献   

13.
Galloanserae is an ancient and diverse avian group, for which comprehensive molecular evidence relevant to phylogenetic analysis in the context of molecular chronology is lacking. In this study, we present two additional mitochondrial genome sequences of Galloanserae (the whistling duck, Dendrocygna javanica, and the black swan, Cygnus atratus) to broaden the scope of molecular phylogenetic reconstruction. The lengths of the whistling duck’s and black swan’s mitochondrial genomes are 16,753 and 16,748 bases, respectively. Phylogenetic analyses suggest that Dendrocygna is more likely to be in a basal position of the branch consisting of Anatinae and Anserinae, an affiliation that does not conform to its traditional classification. Bayesian approaches were employed to provide a rough timescale for Galloanserae evolution. In general, a narrow range of 95% confidence intervals gave younger estimates than those based on limited genes and estimated that at least two lineages originated before the Coniacian epoch around 90 MYA, well before the Cretaceous-Tertiary boundary. In addition, these results, which were compatible with estimates from fossil evidence, also imply that the origin of numerous genera in Anseriformes took place in the late Oligocene to early Miocene. Taken together, the results presented here provide a working framework for future research on Galloanserae evolution, and they underline the utility of whole mitochondrial genome sequences for the resolution of deep divergence.  相似文献   

14.
Clark, A. 1978. Some aspects of the behaviour of whistling ducks in South Africa. Ostrich 49:31-39.

The behaviour of the Whitefaced Whistling Duck Dendrocygna viduata and the Fulvous Whistling Duck D. bicolor wasstudied between 1971 and 1974 on the Witwatersrand, Transvaal. The paper describes and compares behaviour associated with feeding, voice, flight, agonistic situations and copulation in the two species.  相似文献   

15.
Summary Two cases of a variant of the fetal face syndrome are described. The affected babies were born from two consecutive pregnancies to the same gypsy parents. In addition to the classical syndrome, both cases showed a severe feeding difficulties, failure to thrive and severe psychomotoric retardation and one of them cleft lip and palate.  相似文献   

16.
The Aarskog syndrome   总被引:2,自引:0,他引:2  
  相似文献   

17.
CFC syndrome: a syndrome distinct from Noonan syndrome   总被引:2,自引:0,他引:2  
We report two children with a common pattern of birth defects. Both have very sparse, curly hair, nystagmus and mental retardation. The first one has Noonan syndrome habitus associated with keratosis plantaris and nystagmus; the second one has a slightly Noonan-like face, macrocephaly, keratosis pilaris, and hypertrophic cardiomyopathy. They represent the extreme of a spectrum of congenital defects recently reported independently as CFC syndrome by Reynolds and as "Noonan-like short stature syndrome with sparse hair" by Baraitser and Patton. The clinical features are reviewed and the autonomy of the syndrome with regards to Noonan syndrome, is disputed, since every sign seems to occur independently in Noonan syndrome. The father of the second case probably has a minor syndrome expression, pointing to probable autosomal dominant inheritance.  相似文献   

18.
Frey's syndrome, is characterized by warmth, flushing and sweating of the face, most of time in the preauricular region, initiated by any gustatory stimulus. It is frequently related to parotid surgery. A case of Frey's syndrome in a 81‐year‐old female whose long‐delayed clinical onset post‐parotidectomy is presented.  相似文献   

19.
Two cases of median cleft syndrome with associated basal encephalocele are presented. The median cleft face syndrome consists of several craniofacial defects and occurs, as far as we know, sporadically. Extracranial defects should be looked for carefully since they may indicate the presence of a specific syndrome with its own prognosis and mode of inheritance. Basal encephaloceles are sometimes part of the syndrome and may cause serious, or even life-threatening, symptoms. With regard to the treatment of basal encephaloceles there still exists a lot of controversion, but most authors agree that it is better to postpone operation until after the age of three because mortality is lower then.  相似文献   

20.
Eight species of birds (jabiru stork, Jabiru mycteria; maguari stork, Euxenura galeata; king vulture, Sarcoramphus papa; turkey vulture, Cathartes aura; black vulture, Coragyps atrata; Orinoco goose, Neochen jubata; fulvous-whistling duck, Dendrocygna bicolor; black-bellied whistling duck, D. autumnalis) were studied in a large zoo aviary to determine their use of topographical regions (areas), substrates and heights during a 3-month period. Positions of individuals in the aviary were recorded and species were compared to others of the same taxonomic family to determine if they exhibited differential use of space. Resting and self-care were the most frequently recorded behavior patterns. Certain areas, substrates and heights were utilized by each species regardless of behavior. Each species restricted most of its activity to two or three contiguous areas within the aviary. Space use was correlated with the location of food, presence of shade or similarity to substrates utilized in the wild. Only the vultures made appreciable use of heights over 1.5 m above ground level. Conspecifics were found with each other more often than with heterospecifics of the same family. The waterfowl and maguari storks tended to flock. Maguari storks, king vultures, Orinoco geese and fulvous whistling ducks were restricted in their use of space while the other species ranged throughout the aviary. Environmental structure strongly influenced space utilization, and there were indications that intra- and interspecific interactions may have also affected use of space.  相似文献   

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