980 resultados para Syntactic Projection


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A new Sciophilinae-Azana atlantica, sp. n. - is described from the Atlantic Forest in southeastern Brazil. The species has a number of distinctive apomorphic features, including loss of the mid ocellus, reduced mouthparts, Sc short and incomplete, first section of Rs missing, r-m elongated, longitudinal in position, aligned with the second section of Rs ( R(5)), unforked medial and cubital veins, R(4) missing, M(4) entirely absent, gonostyle triangular, with an inner row of elongated spines and a basal, digitiform inner projection. Some of these features are shared with other genera of the Azana-group of Sciophilinae. The shape of the scutum and the strong spines on the gonostyle make it clear that the species belongs in Azana, despite the features that are distinctive from the remaining species in the genus. There are ten species described in Azana to date, from United States, Europe, Sri Lanka, Canary Islands, tropical Africa and Baltic amber. This is the first Neotropical species belonging to the genus. The complete loss of M(4) and the separated gonocoxites suggest that Azana atlantica, sp. n. forms a monophyletic group with the Afrotropical species of the genus. Azana, Morganiella, Neoaphelomera, Neotrizygia, and Trizygia are shown to compose a small clade within the Azana-group of genera. The division of the genus into two subgenera - A. ( Azana) and A. ( Jugazana) - most probably renders A. ( Azana) paraphyletic and it is suggested that this should be for the time being abandoned.

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Independent studies have shown that the median raphe nucleus (MRN) and dorsal hippocampus (DH) are involved in the expression of contextual conditioned fear (CFC). However, studies that examine the integrated involvement of serotonergic mechanisms of the MRN-DH are lacking. To address this issue, a CFC paradigm was used to test whether the serotonergic projections from the MRN to DH can influence CFC. Serotoninergic drugs were infused either into the MRN or DH prior to testing sessions in which freezing and startle responses were measured in the same context where 6 h previously rats received footshocks. A reduction of serotonin (5-HT) transmission in the MRN by local infusions of the 5-HT(1A) agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT) decreased freezing in response to the context but did not reduce fear-potentiated startle. This pattern of results is consistent with the hypothesis that MRN serotonergic mechanisms selectively modulate the freezing response to the aversive context. As for the DH, a decrease in postsynaptic 5-HT receptor activity at projection areas has been proposed to be the main consequence of 5-HT(1A) receptor activation in the MIRN. Intra-DH injections of 8-OH-DPAT inhibited both the freezing and fear-potentiated startle response to the context. To reconcile these findings, an inhibitory mechanism may exist between the incoming 5-HT pathway from the MRN to DH and the neurons of the DH output to other structures. The DH-amygdala or medial prefrontal cortex projections could well be this output circuit modulating the expression of CFC as revealed by measurements of Fos immunoreactivity in these areas. (C) 2009 Elsevier B.V. All rights reserved.

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This paper examines the syntax of indirect objects (IO) in Brazilian Portuguese (BP). Adopting a comparative perspective we propose that BP differs from European Portuguese (EP) in the grammatical encoding of IO. In EP ditransitive contexts, IO is found in two configurations - one projected by a (low) applicative head and another one involving a lexical/true preposition. We propose that the former property is contingent upon the presence of dative Case marking: namely, the morpheme `a` that introduces IO (a-DP), whose corresponding clitic pronoun is `lhe/lhes`. In contrast, important changes in the pronominal system, coupled with the increase in the use of the preposition `para` are taken as evidence for the loss of the low applicative construction in BP. Thus only the configuration with the lexical/true preposition is found in (Standard) BP. We argue that the innovative properties of IO in BP are due to the loss of the (3rd person) dative clitic and the preposition `a` as dative Case markers. Under this view, we further account for the realization of IO as a DP/weak pronoun, found in dialects of the central region of Brazil, which points to a similarity with the English Double Object Construction. Finally we show that the connection between the morphological expression of the dative Case and the expression of parameters supports a view of syntactic change according to which parametric variation is determined in the lexicon, in terms of the formal features of functional heads.

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Previous work examining context effects in children has been limited to semantic context. The current research examined the effects of grammatical priming of word-naming in fourth-grade children. In Experiment 1, children named both inflected and uninflected noun and verb target words faster when they were preceded by grammatically constraining primes than when they were preceded by neutral primes. Experiment 1 used a long stimulus onset asynchrony (SOA) interval of 750 msec. Experiment 2 replicated the grammatical priming effect at two SOA intervals (400 msec and 700 msec), suggesting that the grammatical priming effect does not reflect the operation of any gross strategic effects directly attributable to the long SOA interval employed in Experiment 1. Grammatical context appears to facilitate target word naming by constraining target word class. Further work is required to elucidate the loci of this effect.

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After massive weight loss, one of the stigmas that afflict women is the remaining deformity of the breasts which become flaccid and ptotic, with an absent or flat upper pole. The authors propose the use of a well-established mammaplasty technique to fill the upper pole, reshape the breast cone, and correct ptosis with nipple-areola complex (NAC) repositioning. A total of 16 patients were analyzed; all underwent gastroplasty between 18 and 24 months prior to mammaplasty. The mean age was 41.6 years (range = 26-62) and the mean BMI previous to the mammaplasty was 29.2 kg/m(2) (range = 24.9-38.9). The technique included a dermo-lipo glandular flap pedicled on the inframammary fold (IMF) together with a superior flap containing the NAC. All patients who underwent surgery were satisfied with the outcomes since a more aesthetic breast shape was achieved, with projection of the upper pole and correction of ptosis. Adverse events included dehiscence at the junction point of the flaps in the inframammary fold, which resolved with secondary-intention wound healing in three patients; partial necrosis of the areola in one patient; epidermolysis in one of the NACs in one patient; and infection in one of the breasts in one patient, which resolved with proper antibiotic therapy. When compared to the current mammaplasty techniques performed in formerly obese patients, this is a good surgical option because it uses tissues adjacent to the breast itself and does not require silicone prosthesis for breast augmentation. The patients reported increased self-esteem and improvement in their quality of life.

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Reconstruction of the nipple-areola complex (NAC) is the last stage of breast reconstruction and represents the search for symmetry in regard to the contralateral breast. The objective of this study was to present an areola reconstruction technique with local skin graft to improve the texture and aspect of the reconstructed areola, searching for a natural look. This technique was performed on 122 patients who in the period from January 2000 to December 2005 were submitted to nipple and areola reconstruction. Once the position of the new nipple was determined, markings were made for the reconstruction of the areola. Then the external limit of the new areola was incised and the skin was centripetally deepidermized up to 85% of its diameter. After this procedure the detached skin was repositioned in its bed as a graft and sutured with 4.0 mononylon thread. Incisions with an 11-blade scalpel were then made in V and C forms associated with the detachment of this skin of the receptor area along the local graft so that at the end of the healing process they would determine alterations in the areolar texture mimicking the texture of a normal areola. All patients underwent tattooing 3 months after reconstruction of the NAC taking into account the different shades of the contralateral areola and nipple colors. The use of a local skin graft associated with C and V incisions allowed alteration in the texture of the reconstructed areola. The use of different ink shades for tattooing helped to give a tridimensional aspect to this areola. These factors determined a good aesthetic result in these patients. This areola reconstruction using a local skin graft allows change in the areola texture and a tridimensional aspect similar to that of a normal areola without the inconvenience of grafting from a distance.

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Although N-CAM has previously been implicated in the growth and fasciculation of axons, the development of axon tracts in transgenic mice with a targeted deletion of the 180-kD isoform of the neural cell adhesion molecule (N-CAM-180) appears grossly normal in comparison to wild-type mice. We examined the organization of the olfactory nerve projection from the olfactory neuroepithelium to glomeruli in the olfactory bulb of postnatal N-CAM-180 null mutant mice. Immunostaining for olfactory marker protein revealed the normal presence of fully mature primary olfactory neurons within the olfactory neuroepithelium of mutant mice. The axons of these neurons form an olfactory nerve, enter the nerve fiber layer of the olfactory bulb, and terminate in olfactory glomeruli as in wild-type control animals. The olfactory bulb is smaller and the nerve fiber layer is relatively thicker in mutants than in wild-type mice. Previous studies have revealed that the plant lectin Dolichos biflorus agglutinin (DBA) clearly stains the perikarya and axons of a subpopulation of primary olfactory neurons. Thus, DBA staining enabled the morphology of the olfactory nerve pathway to be examined at higher resolution in both control and mutant animals. Despite a normal spatial pattern of DBA-stained neurons within the nasal cavity, there was a distorted axonal projection of these neurons onto the surface of the olfactory bulb in N-CAM-180 null mutants. In particular, DBA-stained axons formed fewer and smaller glomeruli in the olfactory bulbs of mutants in comparison to wild-type mice. Many primary olfactory axons failed to exit the nerve fiber layer and contribute to glomerular formation. These results indicate that N-CAM-180 plays an important role in the growth and fasciculation of primary olfactory axons and is essential for normal development of olfactory glomeruli. (C) 1997 John Wiley & Sons, Inc.

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A full set of (higher-order) Casimir invariants for the Lie algebra gl(infinity) is constructed and shown to be well defined in the category O-FS generated by the highest weight (unitarizable) irreducible representations with only a finite number of nonzero weight components. Moreover, the eigenvalues of these Casimir invariants are determined explicitly in terms of the highest weight. Characteristic identities satisfied by certain (infinite) matrices with entries from gl(infinity) are also determined and generalize those previously obtained for gl(n) by Bracken and Green [A. J. Bracken and H. S. Green, J. Math. Phys. 12, 2099 (1971); H. S. Green, ibid. 12, 2106 (1971)]. (C) 1997 American Institute of Physics.

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Few studies have focused on the language acquisition of higher multiple birth sets. In this study, the communication skills of 51 triplet children are described. The measures used were: mean length of utterance; type-token ratio; conversational nets; phoneme repertoire; and number of different types of phonological processes used. The data gained were used to compare the communication skills of triplets with those of twins, singletons and normative data available in the literature. Siblings within triplet sets were also compared using language samples obtained from adult-child interactions and when the three children were playing together. The results indicated that the triplets' early communication skills were different from those of both singletons and twins. The triplets' difficulties included delayed syntactic development, limited use of different language functions and delayed phonological development. In contrast, twins' communication profile is characterised by disordered phonological development.

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BACKGROUND AND PURPOSE: There are 2 main hypotheses concerning the cause of mirror movements (MM) in Kallmann syndrome (KS): abnormal development of the primary motor system, involving the ipsilateral corticospinal tract, and lack of contralateral motor cortex inhibitory mechanisms, mainly through the corpus callosum. The purpose of our study was to determine white and gray matter volume changes in a KS population by using optimized voxel-based morphometry (VBM) and to investigate the relationship between the abnormalities and the presence of MM, addressing the 2 mentioned hypotheses. MATERIALS AND METHODS: T1-weighted volumetric images from 21 patients with KS and 16 matched control subjects were analyzed with optimized VBM. Images were segmented and spatially normalized, and these deformation parameters were then applied to the original images before the second segmentation. Patients were divided into groups with and without MM, and a t test statistic was then applied on a voxel-by-voxel basis between the groups and controls to evaluate significant differences. RESULTS: When considering our hypothesis a priori, we found that 2 areas of increased gray matter volume, in the left primary motor and sensorimotor cortex, were demonstrated only in patients with MM, when compared with healthy controls. Regarding white matter alterations, no areas of altered volume involving the corpus callosum or the projection of the corticospinal tract were demonstrated. CONCLUSION: The VBM study did not show significant white matter changes in patients with KS but showed gray matter alterations in keeping with a hypertrophic response to a deficient pyramidal decussation in patients with MM. In addition, gray matter alterations were observed in patients without MM, which can represent more complex mechanisms determining the presence or absence of this symptom.

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Kallmann syndrome (KS), characterized by the association of hypogonadotropic hypogonadism and anosmia, may present many other phenotypic abnormalities, including neurologic features as involuntary movements, called mirror movements (MM). MM etiology probably involves a complex mechanism comprising corticospinal tract abnormal development associated with deficient contralateral motor cortex inhibitory system. In this study, in order to address previous hypotheses concerning MM etiology, we identified and quantified white matter (WM) alterations in 21 KS patients, comparing subjects with and without MM and 16 control subjects, using magnetization transfer ratio (MTR) and T2 relaxometry (R2). Magnetization transfer and 12 double-echo images were acquired in a 1.5 T system. MTR and R2 were calculated pixel by pixel to initially create individual maps, and then, group average maps, co-registered with MNI305 stereotaxic coordinate system. After analysis of selected regions of interest, we demonstrated areas with higher 12 relaxation time and lower MTR values in KS patients, with and without MM, differently involving corticospinal tract projection, frontal lobes and corpus callosum. Higher MTR was observed only in pyramidal decussation when compared in both groups of patients with controls. In conclusion, we demonstrated that patients with KS have altered WM areas, presenting in a different manner in patients with and without MM. These data suggest axonal loss or disorganization involving abnormal pyramidal tracts and other associative/connective areas, relating to the presence or absence of MM. We also found a different pattern of alteration in pyramidal decussation, which can represent the primary area of neuronal disarrangement. (C) 2010 Elsevier B.V. All rights reserved.

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Aims: The dorsal periaqueductal gray area (dPAG) is involved in cardiovascular modulation. Previously, we reported that noradrenaline (NA) microinjection into the dPAG caused a pressor response that was mediated by vasopressin release into the circulation. However, the neuronal pathway that mediates this response is as yet unknown. There is evidence that chemical stimulation of the diagonal band of Broca (dbB) also causes a pressor response mediated by systemic vasopressin release. In the present study, we evaluated the participation of the dbB in the pressor response caused by NA microinjection into the dPAG as well as the existence of neural connections between these areas. Main methods: With the above goal, we verified the effect of the pharmacological ablation of the dbB on the cardiovascular response to NA microinjection into the dPAG of unanesthetized rats. In addition, we microinjected the neuronal tracer biotinylated-dextran-amine (BDA) into the dPAG and looked for efferent projections from the dPAG to the dbB. Key findings: The pharmacologically reversible ablation of the dbB with local microinjection of CoCl(2) significantly reduced the pressor response caused by NA microinjection (15 nmol/50 nL) into the dPAG. In addition, BDA microinjection into the dPAG labeled axons in the dbB, pointing to the existence of direct connections between these areas. Significance: The present results indicate that synapses within the dbB are involved in the pressor pathway activated by NA microinjection into the VAG and direct neural projection from the dPAG to the dbB may constitute the neuroanatomic substrate for this pressor pathway. (C) 2009 Elsevier Inc. All rights reserved.

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In the present study, we describe the cardiovascular effects of local acetylcholine (Ach) microinjection into both the ventrolateral (vlPAG) and dorsal (dPAG) periaqueductal gray areas of anesthetized rats and the possible local receptors involved with these responses. Microinjection of Ach (9, 27, 45 or 81 nmol/50 nL) into the vlPAG caused dose-related depressor responses. These hypotensive responses were blocked by local pretreatment with increasing doses of the nonselective muscarinic antagonist atropine (1, 3 or 9 nmol/50 nL). The microinjection of Ach into the dPAG caused no significant cardiovascular responses in anesthetized rats. In conclusion, the present findings suggest that a cholinergic system present in the vlPAG, but not in the dPAG, is involved with cardiovascular system control. Moreover, these cardiovascular responses evoked by Ach are mediated by muscarinic receptors. (C) 2010 Elsevier B.V. All rights reserved.

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The dorsal periaqueductal gray area (dPAG) is involved in cardiovascular modulation. In a previous study, we reported that noradrenaline (NA) microinjection into the dPAG of rats caused pressor response that was mediated by vasopressin release. Vasopressin is synthesized by magnocellular neurons in the hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei. In the present study, we verified which nuclei mediated the cardiovascular response to NA as well as the existence of direct neural projection from the dPAG to hypothalamic nuclei. Then, we studied the effect of treating either PVN or SON with the nonselective synaptic blocker cobalt chloride (1 mM) on the cardiovascular response to NA (15 nmol) microinjection into dPAG. Attempting to identify neural projections from dPAG to hypothalamic nuclei, we microinjected the neuronal tracer biotinylated-dextran-amine (BDA) into the dPAG and searched varicosity-containing nerve terminals in the PVN and SON. Unilateral cobalt-induced inhibition of synapses in the SON did not affect the cardiovascular response to NA. However, unilateral inhibition of PVN significantly reduced the pressor response to NA. Moreover, cobalt-induced inhibition of synapses in both PVN blocked the pressor response caused by NA microinjected into the dPAG. Microinjection of BDA into the dPAG evidenced presence of varicosity-containing neuronal fibers in PVN but not in SON. The results from cobalt treatment indicated that synapses in PVN mediate the vasopressin-induced pressor response caused by NA microinjection into the dPAG. In addition, the neuroanatomical results from BDA microinjection into the dPAG pointed out the existence of direct neural projections from the dPAG site to the PVN. (C) 2009 Elsevier B.V. All rights reserved.

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The lateral part of intermediate layer of superior colliculus (SCI) is a critical substrate for successful predation by rats. Hunting-evoked expression of the activity marker Fos is concentrated in SCI while prey capture in rats with NMDA lesions in SCI is impaired. Particularly affected are rapid orienting and stereotyped sequences of actions associated with predation of fast moving prey. Such deficits are consistent with the view that the deep layers of SC are important for sensory guidance of movement. Although much of the relevant evidence involves visual control of movement, less is known about movement guidance by somatosensory input from vibrissae. Indeed, our impression is that prey contact with whiskers is a likely stimulus to trigger predation. Moreover, SCI receives whisker and orofacial somatosensory information directly from trigeminal complex, and indirectly from zona incerta, parvicelular reticular formation and somatosensory barrel cortex. To better understand sensory guidance of predation by vibrissal information we investigated prey capture by rats after whisker removal and the role of superior colliculus (SC) by comparing Fos expression after hunting with and without whiskers. Rats were allowed to hunt cockroaches, after which their whiskers were removed. Two days later they were allowed to hunt cockroaches again. Without whiskers the rats were less able to retain the cockroaches after capture and less able to pursue them in the event of the cockroach escaping. The predatory behaviour of rats with re-grown whiskers returned to normal. In parallel, Fos expression in SCI induced by predation was significantly reduced in whiskerless animals. We conclude that whiskers contribute to the efficiency of rat prey capture and that the loss of vibrissal input to SCI, as reflected by reduced Fos expression, could play a critical role in predatory deficits of whiskerless rats. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.