662 resultados para OBLIQUE GLOTTIS


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A multivariate calibration method to determine chemical compositions of systems with severely overlapped bands is proposed. Q mode factors are determined from the spectral data and subsequently rotated using the varimax and oblique transformation of Imbrie. The method is applied to two sets of simulated data to test the sensitivity of analytical results to random experimental error. The chemical concentrations of alanine and threonine mixture are determined from spectral data of the 302,5 - 548,5 nm region.

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The Alhama de Murcia fault is a 85 km long oblique-slip fault, and is related to historical and instrumental seismic activity. A paleoseismic analysis of the Lorca-Totana sector of the fault containing MSK I=VIII historical earthquakes was made in order to identify and quantify its seismic potential. We present 1) the results of the neotectonic, structural and geomorphological analyses and, 2) the results of trenching. In the study area, the Alhama de Murcia fault forms a depressed corridor between two strands, the northwestern fault with morphological and structural features of a reverse component of slip, bounding the La Tercia range to the South, and the southeastern fault strand with evidence of sinistral oblique strike-slip movement. The offset along this latter fault trapped the sediments in transit from the La Tercia range towards the Guadalentín depression. The most recent of these sediments are arranged in three generations of alluvial fans and terraces. The first two trenches were dug in the most recent sediments across the southeastern fault strand. The results indicate a coseismic reverse fault deformation that involved the sedimentary sequence up to the intermediate alluvial fan and the Holocene terrace deposits. The sedimentary evolution observed in the trenches suggests an event of temporary damming of the Colmenar creek drainage to the South due to uplifting of the hanging wall during coseismic activation of the fault. Trench, structural and sedimentological features provide evidence of at least three coseismic events, which occurred after 125,000 yr. The minimum vertical slip rate along the fault is 0.06 mm/yr and the average recurrence period should not exceed 40,000 yr in accordance with the results obtained by fan topographic profiling. Further absolute dating is ongoing to constrain these estimates.

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The equilibria, the spectra and the identities of the species of Cr(VI) that are present in aqueous solution have long been an active subject of discussion in the literature. In this paper, three different chemometric methodologies are applied to sets of UV/Visible spectra of aqueous Cr(VI) solutions, in order to solve a chemical system where there is no available information concerning the composition of the samples nor spectral information about the pure species. Imbrie Q-mode factor analysis, followed by varimax rotation and Imbrie oblique projection, were used to estimate the composition of Cr(VI) equilibrium solutions and, by combining these results with the k-matrix method, to obtain the pure spectra of the species. Evolving factor analysis and self modeling curve resolution were used to confirm the number of the species and the resolution of the system, respectively. Sets of 3.3×10-4 and 3.3×10-5 mol L-1 Cr(VI) solutions, respectively, were analyzed in the pH range from 1 to 12. Two factors were identified, which were related to the chromate ion (CrO4(2-)) and bichromate ion (HCrO4-). The pK of the equilibrium was estimated as 5.8.

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Language switching is omnipresent in bilingual individuals. In fact, the ability to switch languages (code switching) is a very fast, efficient, and flexible process that seems to be a fundamental aspect of bilingual language processing. In this study, we aimed to characterize psychometrically self-perceived individual differences in language switching and to create a reliable measure of this behavioral pattern by introducing a bilingual switching questionnaire. As a working hypothesis based on the previous literature about code switching, we decomposed language switching into four constructs: (i) L1 switching tendencies (the tendency to switch to L1; L1-switch); (ii) L2 switching tendencies (L2-switch); (iii) contextual switch, which indexes the frequency of switches usually triggered by a particular situation, topic, or environment; and (iv) unintended switch, which measures the lack of intention and awareness of the language switches. A total of 582 SpanishCatalan bilingual university students were studied. Twelve items were selected (three for each construct). The correlation matrix was factor-analyzed using minimum rank factor analysis followed by oblique direct oblimin rotation. The overall proportion of common variance explained by the four extracted factors was 0.86. Finally, to assess the external validity of the individual differences scored with the new questionnaire, we evaluated the correlations between these measures and several psychometric (language proficiency) and behavioral measures related to cognitive and attentional control. The present study highlights the importance of evaluating individual differences in language switching using self-assessment instruments when studying the interface between cognitive control and bilingualism.

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In this work, the spectroscopic properties of 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin (TMPP) in solvents of different polarities and water/ethanol mixtures were studied by electronic absorption spectroscopy and resonance light scattering associated with statistical analysis. The molar absorption coefficient and emission maximum of TMPP were dependent on solvent polarity. In the water/ethanol mixture, TMPP remained monomeric up to 25% of water, when it reaches its critical aggregation percentage. Oblique head-to-tail aggregate was found at intermediate water content (35 - 55%), while formation of a J-type aggregate was observed at higher water content (> 60%).

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Most descriptions of the ostrich oropharynx and oesophagus are superficial and supply little meaningful morphological data. The aim of this investigation is describe the ostrich oropharingeal cavity, in order to supply the deficiency of macroscopic data about this important animal. Five heads of 12 to 14-month-old ostriches of either sex were anatomically dissected to expose the oropharynx. The ostrich oropharynx was "bell-shaped" composed by the maxillary and mandibular ramphoteca. The roof and floor presented two distinct regions different in colour of the mucosa. The rostral region was pale pink contrasting to creamy-pink coloured caudal region. The median longitudinal ridge extended rostrally from the apex of the choana to the tip of the beak in the roof and it is clearly more prominent and rigid than the homolog in the floor that appeared thin and stretched rostrally, continuing caudally surrounding the tongue and the laryngeal mound eventually merging with the oesophageal mucosa. The floor was formed by the interramal region, tongue and laryngeal mound containing shield-shaped glottis. It can be concluded that the present study, in addition to confirming the basic features of the oropharynx previously described for the ostrich, clarified the contradictory information presented in the literature and also provided new, unreported morphological data, some of which may be important when studying nutrition and health in these birds.

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Tämän diplomityön tavoitteena on ollut selvittää, kuinka robotisoitua hitsausta on mahdollista hyödyntää teollisuuskaiteiden valmistuksessa. Tutkimusmenetelminä käytettiin kirjallisuusselvitystä, hitsauskokeita ja makrohietutkimuksia. Työssä keskityttiin robottihitsauksen menetelmiin ja työstä on rajattu pois kaikki kustannuslaskelmat sekä alumiinin hitsaus. Hitsattavat materiaalit olivat rakenneteräs ja ruostumaton teräs. Rakenneteräsputken koko oli 42,4 x 2,6 mm ja ruostumattoman putken koko 42,4 x 2,0 mm. Käytetyt liitosmuodot olivat T-liitoksia, joista suorassa T-liitoksessa putkien välinen kulma oli 90 astetta ja vinossa T-liitoksessa noin 45 astetta. Tehdyn selvitystyön ja hitsauskokeiden perusteella voidaan sanoa, että kaiteissa käytettävien materiaalipaksuuksien ja liitosmuotojen hitsaaminen robotilla on mahdollista. Hitsauksen lopputulos riippuu hitsausasennosta ja paras tulos saavutetaan, kun kappaletta pyöritetään hitsauksen aikana siten, että hitsaus tapahtuu koko ajan jalkoasennossa.

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The rhea (Rhea americana americana) is an american bird belonging to Ratite's family. Studies related to its morphology are still scarce. This study aims to describe the macroscopic structures of the oropharyngeal cavity. Five heads (2 to 6 months old) formalin preserved were anatomically dissected to expose the oropharynx. The oropharynx of the rhea was "bell-shaped" composed by the maxillary and mandibular rhamphotheca. The roof and floor presented two distinct regions different in colour of the mucosa. The rostral region was pale pink contrasting to grey coloured caudal region. The median longitudinal ridge extended rostrally from the apex of the choana to the tip of the beak in the roof and it is clearly more prominent and rigid than the homolog in the floor that appeared thin and stretched merely along the rostral portion of the regio interramalis. The floor was formed by the interramal region, (regio interramalis) tongue and laryngeal mound containing glove-shaped glottis. This study confirmed the basic morphology of the oropharinx of the rhea. However, important morphological information not previously described is highlighted and contradictory information present in the literature is clarified.

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In Velloziaceae, the number of subsidiary cells has been used to characterize species and support groups. Nevertheless, the homology of the stomatal types have not been scrutinized. Stomatal ontogenesis of Vellozia epidendroides and V. plicata, assigned to have tetracytic stomata, and of V. glauca and Barbacenia riparia, assigned to have paracytic stomata, were investigated. In the four species studied, stomata followed perigenic development. Subsidiary cells arise from oblique divisions of neighbouring cells of the guard mother cell (GMC). These cells are elongated and parallel to the longer axis of the stoma. Polar cells show wide variation, following the shape and size of the epidermal cells in the vicinity. Hence, these cells cannot be called subsidiary cells. This wide variation is due to a much higher density of stomata in some regions of the leaf blade. This distribution of stomata forces the development of short polar cells, leading to an apparently tetracytic stomata. In regions of low concentration of stomata, higher spatial availability between the GMCs allows the elongation of polar cells, leading to evident paracytic stomata. Therefore, the four studied species are considered braquiparacytic, questioning the classification of stomata into tetracytic and paracytic in Velloziaceae.

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Systemic blood flow (Q) was measured by echodopplercardiography in 5 normal young adult males during apnea, eupnea and tachypnea. Measurements were made in a recumbent posture at 3-min intervals. Tachypnea was attained by doubling the respiratory frequency at eupnea at a constant tidal volume. An open glottis was maintained during apnea at the resting respiratory level. The Q values were positively correlated with the respiratory frequency, decreasing from eupnea to apnea and increasing from eupnea to tachypnea (P<0.05). These data demonstrate that echodopplercardiography, a better qualified tool for this purpose, confirms the positive and progressive effects of ventilation on systemic blood flow, as suggested by previous studies based on diverse technical approaches

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The present study evaluated functional changes of quadriceps muscle after injury induced by eccentric exercise. Maximal isometric torque of quadriceps and the surface electromyography (root mean square, RMS, and median frequency, MDF) of the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles were examined before, immediately after and during the first 7 days after injury. Serum creatine kinase (CK) levels and magnetic resonance imaging (MRI) were used to identify muscle injury. The subject was used as her own control and percent refers to pre-injury data. Experiments were carried out with a sedentary 23-year-old female. Injury was induced by 4 bouts of 15 maximal isokinetic eccentric contractions (angular velocity of 5º/s; range of motion from 40º to 110º of knee flexion). The isometric torque of the quadriceps (knee at 90º flexion) decreased 52% immediately after eccentric exercise and recovered on the 5th day. The highest reduction of RMS occurred on the 2nd day after injury in both VL (63%) and VMO (66%) and only VL recovered to the pre-injury level on the 7th day. Immediately after injury, the MDF decreased by 5 and 3% (VMO and VL, respectively) and recovered one day later. Serum CK levels increased by 109% on the 2nd day and were still increased by 32% on the 7th day. MRI showed large areas of injury especially in the deep region of quadriceps. In conclusion, eccentric exercise decreased the isometric torque and electromyographic signals of quadriceps muscle, which were recovered in one week, despite the muscle regeneration signals.

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In this doctoral thesis, a tomographic STED microscopy technique for 3D super-resolution imaging was developed and utilized to observebone remodeling processes. To improve upon existing methods, wehave used a tomographic approach using a commercially available stimulated emission depletion (STED) microscope. A certain region of interest (ROI) was observed at two oblique angles: one at a standard inverted configuration from below (bottom view) and another from the side (side view) via a micro-mirror positioned close to the ROI. The two viewing angles were reconstructed into a final tomogram. The technique, named as tomographic STED microscopy, was able to achieve an axial resolution of approximately 70 nm on microtubule structures in a fixed biological specimen. High resolution imaging of osteoclasts (OCs) that are actively resorbing bone was achieved by creating an optically transparent coating on a microscope coverglass that imitates a fractured bone surface. 2D super-resolution STED microscopy on the bone layer showed approximately 60 nm of lateral resolution on a resorption associated organelle allowing these structures to be imaged with super-resolution microscopy for the first time. The developed tomographic STED microscopy technique was further applied to study resorption mechanisms of OCs cultured on the bone coating. The technique revealed actin cytoskeleton with specific structures, comet-tails, some of which were facing upwards and some others were facing downwards. This, in our opinion, indicated that during bone resorption, an involvement of the actin cytoskeleton in vesicular exocytosis and endocytosis is present. The application of tomographic STED microscopy in bone biology demonstrated that 3D super-resolution techniques can provide new insights into biological 3D nano-structures that are beyond the diffraction-limit when the optical constraints of super-resolution imaging are carefully taken into account.

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Gamma-aminobutyric acid (GAB A) is a ubiquitous non-protein amino acid synthesized via the decarboxylation of L-glutamate in a reaction catalyzed by the cytosolic enzyme L-glutamate decarboxylase (GAD). In animals it functions as an inhibitory neurotransmitter. In plants it accumulates rapidly in response to various stresses, but its function remains unclear. The hypothesis that GABA accumulation in leaf tissue may function as a plant resistance mechanism against phytophagous insect activity was investigated. GABA accumulation in response to mechanical stimulation, mechanical damage and insect activity was demonstrated. In wt tobacco (Nicotiana tabacum cv Samsun), mechanical stimulation or damage caused GABA to accumulate within 2 min from mean levels of 14 to 37 and 1~9 nmol g-l fresh weight (FW), respectively. In the transgenic tobacco strain CaMVGAD27c overexpressing Petunia GAD, the same treatments caused GABA to accumulate from 12 to 59 and 279 nmol g-l FW, respectively. In the transgenic tobacco strain CaMVGADilC 11 overexpressing Petunia GAD lacking an autoinhibitory domain, mechanical stimulation or damage caused GABA to accumulate from 180 to 309 and 630 nmol g-l FW, respectively. Ambulatory activity by tobacco budworm (TBW) larvae (Heliothis virescens) on leaves of CaMVGAD27c tobacco caused GABA to accumulate from 28 to 80 nmol g-l FW within 5 min. Ambulatory and leaf-rolling activity by oblique banded leaf roller (OBLR) larvae (Choristoneura rosaceana cv Harris) on wt soybean leaves (Glycine max cv Harovinton) caused GABA to accumulate from 60 to 1123 nmol g-l FW within 20 min. Increased GABA levels in leaf tissue were shown to affect phytophagous preference in TBW larvae presented with wt and transgenic tobacco leaves. When presented with leaves of Samsun wt and CaMVGAD27c plants, TBW larvae consumed more wt leaf tissue (640 ± 501 S.D. mm2 ) than transgenic leaf tissue (278 ± 338 S.D. mm2 ) nine times out of ten. When presented with leaves of Samsun wt and CaMVGAD~C11 plants, TBW larvae consumed more transgenic leaf tissue (1219 ± 1009 S.D. mm2 ) than wt leaf tissue (28 ± 31 S.D. mm2 ) ten times out of ten. These results indicate that: (1) ambulatory activity of insect larvae on leaves results in increased GABA levels, (2) transgenic tobacco leaves with increased capacity for GABA synthesis deter feeding, and (3) transgenic tobacco leaves with constitutively higher GABA levels stimulate feeding.