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Transverse pseudo-nonlinear effects measured in solid-state laser materials using a sensitive time-resolved technique

Godin, T.; Fromager, M.; Cagniot, E.; Poree, F.; Catunda, Tomaz; Moncorge, R.; Ait-Ameur, K.
Fonte: SPRINGER; NEW YORK Publicador: SPRINGER; NEW YORK
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.71%
We present a detailed study of the Baryscan technique, a new efficient alternative to the widespread Z-scan technique which has been demonstrated [Opt. Lett. 36:8, 2011] to reach among the highest sensitivity levels. This method is based upon the measurement of optical nonlinearities by means of beam centroid displacements with a position sensitive detector and is able to deal with any kind of lensing effect. This technique is applied here to measure pump-induced electronic refractive index changes (population lens), which can be discriminated from parasitic thermal effects by using a time-resolved Baryscan experiment. This method is validated by evaluating the polarizability variation at the origin of the population lens observed in the reference Cr3+:GSGG laser material.; Conseil Regional Basse-Normandie; Conseil Regional BasseNormandie

"Estudo das alterações esqueléticas da região maxilar em pacientes submetidos à expansão rápida da maxila assistida cirurgicamente avaliadas por tomografia computadorizada" ; Computed Tomography evaluation of maxillary skeletal changes after surgically assisted rapid palatal expansion

Goldenberg, Dov Charles
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 18/08/2006 PT
Relevância na Pesquisa
26.06%
A expansão rápida da maxila assistida cirurgicamente (ERMAC) é o procedimento de eleição para o tratamento da deficiência transversa de maxila em pacientes esqueleticamente maduros. Controvérsias em relação ao procedimento ainda persistem principalmente relacionadas aos métodos de avaliação, técnica cirúrgica utilizada, morbidade, eficácia clínica e estabilidade de resultados. A utilização da tomografia computadorizada para a avaliação da eficiência da ERMAC é uma opção atual e ainda pouco divulgada. Consequentemente, os parâmetros anatômicos para a utilização deste método ainda não foram totalmente estabelecidos. Os objetivos do presente estudo foram avaliar a confiabilidade da metodologia proposta e as alterações esqueléticas maxilares decorrentes da ERMAC com a utilização do método de avaliação por tomografia computadorizada. No período de junho de 2004 a maio de 2005, 15 pacientes, sendo 10 do sexo feminino, foram submetidos a ERMAC. A técnica cirúrgica utilizada constou de osteotomia maxilar do tipo Le Fort I, sem osteotomia da sutura ptérigo-maxilar, associada a osteotomia sagital mediana do palato. O aparelho expansor utilizado foi do tipo Hyrax. Os pacientes foram submetidos a exames de tomografia computadorizada...

Estudo da segurança e da estabilidade do implante de cabo-eletrodo atrial direito pela via epidemiocárdiaca através do seio transverso em modelo animal suíno; Evaluation of safety and stability of right atrial lead implantation by epimyocardial access through the transverse sinus in a swine model

Bueno, Sávia Christina Pereira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 13/06/2013 PT
Relevância na Pesquisa
35.99%
Introdução: Embora o implante de marcapasso atrioventricular pela via endovenosa seja considerado o estado da arte, situações clínicas e técnicas que podem impossibilitar o implante transvenoso de cabos-eletrodos têm sido cada vez mais frequentes, tornando-se necessária a proposição de abordagens cirúrgicas alternativas. Objetivos: O presente estudo visou o implante de marcapasso atrioventricular utilizando nova técnica para implante de cabo-eletrodo atrial no átrio direito, com o objetivo de avaliar no período intra-operatório e nos 30 primeiros dias de seguimento: a segurança e a reprodutibilidade do procedimento cirúrgico; a taxa de deslocamento dos cabos-eletrodos; as condições de estimulação e sensibilidade; as alterações morfológicas na cavidade pericárdica e as alterações histopatológicas epimiocárdicas. Métodos: Sob anestesia geral, foram operados 10 porcos adultos da raça Large White. Os cabos-eletrodos foram implantados, sob visão direta, no ventrículo esquerdo e no átrio direito, pelo seio transverso, através de toracotomia anterolateral esquerda. As condições de estimulação e de sensibilidade para os cabos-eletrodos atrial e ventricular, nas configurações unipolar e bipolar, foram avaliadas no intra-operatório...

Histoenzymological and ultrastructural changes in lateral muscle fibers of Oreochromis niloticus (Teleostei: Cichlidae) after local injection of veratrine

Silva Freitas, Erika Maria; Dal Pai Silva, Maeli; Da Cruz-Höfling, Maria Alice
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 525-534
ENG
Relevância na Pesquisa
35.8%
The effects of veratrine have been investigated in mammalian, amphibian, and crustacean muscle, but not in fish. In this work, the action of veratrine was studied in the lateral muscle of the freshwater teleost Oreochromis niloticus after intramuscular injection. Histoenzymological typing and electron microscopy of muscle fibers before and 15, 30, and 60 min after veratrine injection (10 ng/kg fish) were used to indirectly assess the morphological changes and the oxidative and m-ATPase activities. In some cases, muscles were pretreated with tetrodotoxin to determine whether the ultrastructural changes were the result of Na+ channel activation by veratrine. Veratrine altered the metabolism of fibers mainly after 30 min. Oxidative fibers showed decreased NADH-TR activity, whereas that of glycolytic and oxidative-glycolytic type fibers increased. There was no change in the m-ATPase activity of the three fiber types, except at 60 min postveratrine, when a novel fiber type, which showed no reversal after acidic and alkaline preincubations, appeared. Ultrastructural damage involved sarcomeres, myofibrils, and mitochondria, but the T-tubules remained intact. Pretreatment with tetrodotoxin (1 ng/ml) prevented the ultrastructural changes caused by veratrine. These results show that in fish skeletal muscle veratrine produces some effects that are not seen in mammalian muscle.

Transverse changes after surgically assisted rapid palatal expansion

Gurgel, Júlio de Araújo; Tiago, C. M.; Normando, D.
Fonte: Churchill Livingstone Publicador: Churchill Livingstone
Tipo: Artigo de Revista Científica Formato: 316-322
ENG
Relevância na Pesquisa
56.03%
The aim of this retrospective study was to investigate the amount of skeletal and dental expansion in patients submitted to surgically assisted rapid palatal expansion (SARPE). The sample consisted of 21 patients (14 female and seven male) with a mean age of 25.4 years (range 17.4-41.8 years). Postero-anterior (PA) cephalograms were taken pre-expansion (T1), immediately after expansion (T2), and at post-expansion retention of 120 days (T3). SARPE promoted significant transverse skeletal changes, which were maintained from T2 to T3. Dentoalveolar expansion and dental tipping were also observed in the region of the first molars and first premolars; however the net effect at the first molars was significantly less than that at the first premolars. No statistically significant effect on the width of the nasal cavity was observed. The findings indicate that peculiarities inherent to dental effects may influence the clinical options for SARPE. Skeletal expansions with SARPE were significant and stable. Dental changes were different between molars and premolars. The transverse changes after SARPE should be observed for future procedures related to the retention and the completion of orthodontic treatment.

Volumetric upper airway assessment in patients with transverse maxillary deficiency after surgically assisted rapid maxillary expansion

Pereira-Filho, V. A.; Monnazzi, M. S.; Gabrielli, M. A. C.; Spin-Neto, R.; Watanabe, E. R.; Gimenez, C. M. M.; Santos-Pinto, A.; Gabrielli, M. F. R.
Fonte: Churchill Livingstone Publicador: Churchill Livingstone
Tipo: Artigo de Revista Científica Formato: 581-586
ENG
Relevância na Pesquisa
36.06%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Transverse maxillary deficiency is commonly found in patients with sleep apnea and is also related to abnomial breathing patterns. Maxillary expansion procedures promote widening of the nasal floor and reduce the resistance to airflow, and have a positive influence on nasopharynx function. In order to evaluate volume changes in the upper airway, 15 adult patients with transverse maxillary deficiency underwent surgically assisted rapid maxillary expansion (RME) until a slight overcorrection of the crossbite was obtained. Cone beam computed tomography (CBCT) volumetric images were obtained at three predefined time points. The mean age of the patients was 30.2 (+/- 7.4) years; nine were females and six were males. The area, volume, and the smallest transverse section area of the airway were assessed using Dolphin Imaging 3D software. Statistical comparisons were made of the changes between time periods. No statistically significant differences were found for volume or area. However a significant difference was found between the preoperative and immediate postoperative smallest transverse section area (P < 0.05). Maxillary expansion, as an isolated procedure, does not result in a statistically significant improvement in the airway dimensions and results in an inferior relocation of the smallest transverse section area.

Avaliação tridimensional das alterações maxilomandibulares após expansão rápida de maxila assistida cirurgicamente

Oliveira, Talles Fernando Medeiros de
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 107. : il., anexo
POR
Relevância na Pesquisa
26.01%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Pós-graduação em Ciências Odontológicas - FOAR; Surgically assisted rapid maxillary expansion (SARME) is an effective treatment for maxillary transverse deficiency in adult patients. This study assessed the influence of two different osteotomy designs of the maxillary lateral wall on maxillary transverse changes, mandibular positioning and condyle fossa relationship after SARME. Thirty adult patients were divided into two groups according to the lateral osteotomy design: Group 1 (n = 16) underwent lateral osteotomy performed in a horizontal straight fashion and Group 2 (n = 14) underwent lateral osteotomy performed parallel to the occlusal plane with a step at the zygomatic buttress. Cone beam computed tomography scans were obtained before surgery (T1), immediately after expansion (T2) and six months after expansion (T3). The lateral osteotomy design had no bearing on the maxillomandibular changes after SARME. Both groups showed an increase in maxillary transverse measurements and clockwise rotation with lateral displacement of the mandible immediately after expansion. Maxillary changes showed to be stable six months after SARME, except for nasal floor width and tooth tipping which decreased at T3. Mandibular displacements tended to return close to their initial values at T3. No significant changes in condyle fossa relationship were observed at any time points. The design of lateral osteotomy of the maxilla did not affect the outcomes of SARME...

Transversal changes in dental arches from non-extraction treatment with self ligating brackets

Maltagliati,Liliana Avila; Myiahira,Yasushi Inoue; Fattori,Liana; Capelozza Filho,Leopoldino; Cardoso,Mauricio
Fonte: Dental Press International Publicador: Dental Press International
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
Relevância na Pesquisa
35.98%
OBJECTIVE: The present study aimed at analyzing, with the use of dental casts, the transverse changes of the upper and lower dental arches, after non-extraction orthodontic treatment, with self-ligating brackets. METHODS: The sample comprised 29 patients, all presenting Class I malocclusion with upper and lower crowding of at least 4 mm and treated only with a fixed appliance, without stripping, extraction or distalization. The dental casts were obtained before and after leveling with 0.019 x 0.025-in stainless steel archwires. CONCLUSION: The results indicated that the majority of transverse changes occurred at the premolar areas, both the first and the second, as well as on the upper and lower dental arches. The intercanine distance increased 0.75 mm, on average, in the upper arch and 1.96 mm in the lower arch. The molars also demonstrated a tendency towards an increase in their transverse dimension, however, at a lower intensity comparing to premolars. All measurements presented statistically significant differences with the exception of the maxillary second molars.

Stiffness changes in frog skeletal muscle during contraction recorded using ultrasonic waves.

Hatta, I; Sugi, H; Tamura, Y
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1988 EN
Relevância na Pesquisa
26.09%
1. A technique has been developed with which the stiffness changes in frog skeletal muscle can be continuously recorded by measuring the propagation velocity of ultrasonic waves (3-7 MHz) with negligibly small perturbations to the contractile system. 2. The resting muscle stiffness was 2.256 +/- 0.002 x 10(9) N/m2 (S.D.) at 1-2 degrees C (n = 10) and 2.480 +/- 0.007 x 10(9) N/m2 at 19-20 degrees C (n = 12) in the longitudinal direction, and 2.223 +/- 0.008 x 10(9) N/m2 at 1-2 degrees C (n = 8) and 2.437 +/- 0.007 x 10(9) N/m2 at 19-20 degrees C (n = 9) in the transverse direction. 3. The resting muscle stiffness measured with ultrasonic waves was virtually insensitive to the resting force development, i.e. the extension of the parallel elastic component. 4. The longitudinal muscle stiffness increased during isometric contraction at a rate faster than the force development. The amount of increase of the longitudinal stiffness in an isometric tetanus at 2.2 microns sarcomere length was 2.4 +/- 0.1 x 10(7) N/m2 at 1-2 degrees C (n = 10) and 6.5 +/- 1.3 x 10(7) N/m2 at 19-20 degrees C (n = 12). 5. On the other hand, the transverse muscle stiffness decreased during isometric contraction at a rate faster than the force development. The amount of decrease of the transverse stiffness in an isometric tetanus at 2.2 microns sarcomere length was 5.6 +/- 0.1 x 10(7) N/m2 at 1-2 degrees C (n = 8) and 6.4 +/- 0.3 x 10(7) N/m2 at 19-20 degrees C (n = 9). 6. The amount of both the longitudinal and the transverse stiffness changes during an isometric tetanus decreased linearly with increasing sarcomere length...

Phase contrast coherence microscopy based on transverse scanning

Pircher, Michael; Baumann, Bernhard; Götzinger, Erich; Sattmann, Harald; Hitzenberger, Christoph K.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/06/2009 EN
Relevância na Pesquisa
26.01%
We present what we believe to be a novel approach to measuring optical path length differences with a precision of a few nanometers. The instrument is based on transverse scanning or en-face optical coherence tomography. Owing to the fast motion of the scanning beam over the sample, excellent phase stability in the transverse direction is achieved. Hence, phase changes caused by the varying optical path lengths within the sample arm occur with high frequency in the fast scanning direction. These changes are well separated from the rather slow phase changes introduced by jitter within the interferometer and can therefore be measured. The en-face imaging speed of the instrument is 40 fps (520×200 pixels). The measured precision of the method to detect small changes in optical path lengths was ~3 nm.

Rapid monitoring of iron-chelating therapy in thalassemia major by a new cardiovascular MR measure: the reduced transverse relaxation rate

Kim, Daniel; Jensen, Jens H.; Wu, Ed X.; Feng, Li; Au, Wing-Yan; Cheung, Jerry S.; Ha, Shau-Yin; Sheth, Sujit S.; Brittenham, Gary M.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.06%
In iron overload, almost all the excess iron is stored intracellularly as rapidly mobilizable ferritin iron and slowly exchangeable hemosiderin iron. Increases in cytosolic iron may produce oxidative damage that ultimately results in cardiomyocyte dysfunction. Because intracellular ferritin iron is evidently in equilibrium with the low-molecular-weight cytosolic iron pool, measurements of ferritin iron potentially provide a clinically useful indicator of changes in cytosolic iron. The cardiovascular magnetic resonance (CMR) index of cardiac iron used clinically, the effective transverse relaxation rate (R2*), is principally influenced by hemosiderin iron and changes only slowly over several months, even with intensive iron-chelating therapy. Another conventional CMR index of cardiac iron, the transverse relaxation rate (R2), is sensitive to both hemosiderin iron and ferritin iron. We have developed a new MRI measure, the ‘reduced transverse relaxation rate’ (RR2), and have proposed in previous studies that this measure is primarily sensitive to ferritin iron and largely independent of hemosiderin iron in phantoms mimicking ferritin iron and human liver explants. We hypothesized that RR2 could detect changes produced by 1 week of iron-chelating therapy in patients with transfusion-dependent thalassemia. We imaged 10 patients with thalassemia major at 1.5 T in mid-ventricular short-axis planes of the heart...

Effects of chronic low back pain on trunk coordination and back muscle activity during walking: changes in motor control

Lamoth, Claudine J. C.; Meijer, Onno G.; Daffertshofer, Andreas; Wuisman, Paul I. J. M.; Beek, Peter J.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.03%
Low back pain (LBP) is often accompanied by changes in gait, such as a decreased (preferred) walking velocity. Previous studies have shown that LBP diminishes the normal velocity-induced transverse counter-rotation between thorax and pelvis, and that it globally affects mean erector spinae (ES) activity. The exact nature and causation of these effects, however, are not well understood. The aim of the present study was to examine in detail the effect of walking velocity on global trunk coordination and ES activity as well as their variability to gain further insights into the effects of non-specific LBP on gait. The study included 19 individuals with non-specific LBP and 14 healthy controls. Gait kinematics and ES activity were recorded during treadmill walking at (1) a self-selected (comfortable) velocity, and (2) sequentially increased velocities from 1.4 up to maximally 7.0 km/h. Pain intensity, fear of movement and disability were measured before the experiment. The angular movements of thorax, lumbar and pelvis were recorded in three dimensions. ES activity was recorded with pairs of surface electrodes. Trunk–pelvis coordination and mean amplitude of ES activity were analyzed. In addition, invariant and variant properties of trunk kinematics and ES activity were studied using principal component analysis (PCA). Comfortable walking velocity was significantly lower in the LBP participants. In the transverse plane...

Transverse and dorso-ventral changes in thoracic dimension during equine locomotion

Thorpe, C.; Marlin, D.; Franklin, S.; Colborne, G.
Fonte: Bailliere Tindall Publicador: Bailliere Tindall
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
26.17%
Changes in shape of the equine thorax during locomotion are not well defined, although it has been shown recently that the transverse hemi-diameter changes its dimension by up to 80mm on the side of the trailing forelimb during gallop, despite minimal change in thoracic circumference. The aim of this project was to analyse transverse and dorso-ventral changes in shape of the thorax simultaneously, and to determine if leading limb, treadmill slope and speed have an effect on these shape changes. Reflective markers were placed on the horse's hemi-thorax and movement of the markers was recorded using a motion capture system while the horse trotted and cantered on a treadmill. Treadmill speed and slope, and the lead the horse cantered on were varied to determine the effects these had on transverse hemi-diameter and dorso-ventral diameter. There was a negative correlation between transverse and dorso-ventral changes in thoracic dimension, the strength of which increased with speed on the trailing limb side. On the leading side, the relationship was either weakly negative or positive. The changes in dimension of the hemi-thorax were significantly greater on the trailing side compared to the leading side. Speed had small effects on thoracic shape changes...

Évaluation de la stabilité de l'ostéotomie de type LeFort I multisegmentaire

Engel, Hélène
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
Relevância na Pesquisa
26.06%
Introduction : Cette étude vise à évaluer la stabilité de la chirurgie LeFort I multisegmentaire à moyen (fin du traitement orthodontique) et à long termes dans les trois plans de l'espace (transversal, antéro-postérieur et vertical). Matériel et méthodes : L'échantillon étudié est composé de 31 patients traités en clinique privée, ayant eu une chirurgie LeFort I multisegmentaire en deux, trois ou quatre morceaux, et ayant terminé leur traitement orthodontique. Parmi eux, 17 patients ayant terminé leur traitement orthodontique depuis plus de deux ans (moyenne de trois ans post-traitement) ont permis d'évaluer la stabilité de la procédure chirurgicale à long terme. La collecte des données a été réalisée sur des modèles et des radiographies céphalométriques latérales pris à des temps précis tout au long du traitement orthodontique, ainsi que pendant la période de contention. Concernant l'analyse statistique, des T-tests et des corrélations de Pearson ont été utilisés. Le test de Bland-Altman et le coefficient de corrélation intra-classe ont permis d'analyser les fiabilités intra-examinateur et inter-examinateurs. Résultats : Une récidive transverse significative, mais très faible cliniquement...

Evaluation of transverse changes in the dental arches according to growth pattern: a longitudinal study

Ribeiro, Jucienne Salgado; Ambrosio, Aldrieli Regina; dos Santos-Pinto, Ary; Shimizu, Isabella Almeida; Shimizu, Roberto Hideo
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 66-73
ENG
Relevância na Pesquisa
55.95%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Objective: To evaluate changes in intercanine (LICW and UICW) and intermolar (LIMW and UIMW) widths on the dental arches of subjects with normal occlusion and Angle Class I malocclusion during the transition to permanent dentition, and evaluate whether or not facial pattern influences on the normal development of the dentition and occlusion. Methods: Nineteen Caucasian Brazilian children were selected, with ages ranging from 6 to 8.6 years at T1 and from 10.10 to 14.2 years at T2. Their second records consisted of study dental casts and a lateral cephalometric radiograph. To obtain intermolar and intercanine widths a three-dimensional scanner unit (digitizer MicroScribe 3DX) was used connected to a microcomputer. To analyze changes at T1 and T2 Student's paired t-test was applied, whereas Spearman's correlation analysis was used to assess the relationship between measurements obtained at T1 and T2 and the facial pattern, both at 95% level of confidence. Results: The mean values found on each assessment time (T1 and T2) were statistically different (p=0.000 for LICW, p=0.001 for UICW, p=0.000 for UIMW, and p=0.046 for LIMW), regardless of the facial pattern. The anterior dimensions...

Three-dimensional dental arch changes of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusion

Peixoto,Adriano Porto; Pinto,Ary dos Santos; Garib,Daniela Gamba; Gonçalves,João Roberto
Fonte: Dental Press International Publicador: Dental Press International
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 EN
Relevância na Pesquisa
26.01%
INTRODUCTION: This study assessed the three-dimensional changes in the dental arch of patients submitted to orthodontic-surgical treatment for correction of Class II malocclusions at three different periods. METHODS: Landmarks previously identified on upper and lower dental casts were digitized on a three-dimensional digitizer MicroScribe-3DX and stored in Excel worksheets in order to assess the width, length and depth of patient's dental arches. RESULTS: During orthodontic preparation, the maxillary and mandibular transverse dimensions measured at the premolar regions were increased and maintained throughout the follow-up period. Intercanine width was increased only in the upper arch during orthodontic preparation. Maxillary arch length was reduced during orthodontic finalization, only. Upper and lower arch depths were stable in the study periods. Differences between centroid and gingival changes suggested that upper and lower arch premolars buccaly proclined during the pre-surgical period. CONCLUSIONS: Maxillary and mandibular dental arches presented transverse expansion at premolar regions during preoperative orthodontic preparation, with a tendency towards buccal tipping. The transverse dimensions were not altered after surgery. No sagittal or vertical changes were observed during the follow-up periods.

Evaluation of transverse changes in the dental arches according to growth pattern: a longitudinal study

Ribeiro,Jucienne Salgado; Ambrosio,Aldrieli Regina; Santos-Pinto,Ary dos; Shimizu,Isabella Almeida; Shimizu,Roberto Hideo
Fonte: Dental Press International Publicador: Dental Press International
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2012 EN
Relevância na Pesquisa
55.95%
OBJECTIVE: To evaluate changes in intercanine (LICW and UICW) and intermolar (LIMW and UIMW) widths on the dental arches of subjects with normal occlusion and Angle Class I malocclusion during the transition to permanent dentition, and evaluate whether or not facial pattern influences on the normal development of the dentition and occlusion. METHODS: Nineteen Caucasian Brazilian children were selected, with ages ranging from 6 to 8.6 years at T1 and from 10.10 to 14.2 years at T2. Their second records consisted of study dental casts and a lateral cephalometric radiograph. To obtain intermolar and intercanine widths a three-dimensional scanner unit (digitizer MicroScribe 3DX) was used connected to a microcomputer. To analyze changes at T1 and T2 Student's paired t-test was applied, whereas Spearman's correlation analysis was used to assess the relationship between measurements obtained at T1 and T2 and the facial pattern, both at 95% level of confidence. RESULTS: The mean values found on each assessment time (T1 and T2) were statistically different (p=0.000 for LICW, p=0.001 for UICW, p=0.000 for UIMW, and p=0.046 for LIMW), regardless of the facial pattern. The anterior dimensions, UICW and LICW, increased by 3.21 mm and 1.52 mm, respectively. And the posterior dimensions...

Non-monotonic Dynamics in Frustrated Ising Model with Time-Dependent Transverse Field

Tanaka, Shu; Miyashita, Seiji
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.03%
We study how the degree of ordering depends on the strength of the thermal and quantum fluctuations in frustrated systems by investigating the correlation function of the order parameter. Concretely, we compare the equilibrium spin correlation function in a frustrated lattice which exhibits a non-monotonic temperature dependence (reentrant type dependence) with that in the ground state as a function of the transverse field that causes the quantum fluctuation. We find the correlation function in the ground state also shows a non-monotonic dependence on the strength of the transverse field. We also study the real-time dynamics of the spin correlation function under a time-dependent field. After sudden decrease of the temperature, we found non-monotonic changes of the correlation function reflecting the static temperature dependence, which indicates that an effective temperature of the system changes gradually. For the quantum system, we study the dependence of changes of the correlation function on the sweeping speed of the transverse field. Contrary to the classical case, the correlation function varies little in a rapid change of the field, though it shows a non-monotonic change when we sweep the field slowly.; Comment: 18 pages, 9 figures

Electrically tunable transverse magnetic focusing in graphene

Taychatanapat, Thiti; Watanabe, Kenji; Taniguchi, Takashi; Jarillo-Herrero, Pablo
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/01/2013
Relevância na Pesquisa
26.02%
Electrons in a periodic lattice can propagate without scattering for macroscopic distances despite the presence of the non-uniform Coulomb potential due to the nuclei. Such ballistic motion of electrons allows the use of a transverse magnetic field to focus electrons. This phenomenon, known as transverse magnetic focusing (TMF), has been used to study the Fermi surface of metals and semiconductor heterostructures, as well as to investigate Andreev reflection, spin-orbit interaction, and to detect composite fermions. Here we report on the experimental observation of transverse magnetic focusing in high mobility mono-, bi-, and tri-layer graphene devices. The ability to tune the graphene carrier density enables us for the first time to investigate TMF continuously from the hole to the electron regime and analyze the resulting focusing fan. Moreover, by applying a transverse electric field to tri-layer graphene, we use TMF as a ballistic electron spectroscopy method to investigate controlled changes in the electronic structure of a material. Finally, we demonstrate that TMF survives in graphene up to 300 K, by far the highest temperature reported for any system, opening the door to novel room temperature applications based on electron-optics.; Comment: Nature Physics...

The determinants of transverse tubular volume in resting skeletal muscle

Sim, Jingwei; Fraser, James A.
Fonte: Wiley Publicador: Wiley
Tipo: Article; published version
EN
Relevância na Pesquisa
36.01%
This is the final version. It was first published by Wiley at http://onlinelibrary.wiley.com/doi/10.1113/jphysiol.2014.281170/abstract.; The transverse tubular (t-) system of skeletal muscle couples sarcolemmal electrical excitation with contraction deep within the fibre. Exercise, pathology, and the composition of the extracellular fluid (ECF) can alter t-system volume (t-volume). T-volume changes likely contribute to fatigue, rhabdomyolysis, and disruption of excitation-contraction coupling. Nevertheless, mechanisms that underlie t-volume changes are poorly understood. A multicompartment, history-independent computer model of rat skeletal muscle was developed to define the minimum conditions for t-volume stability. It was found that the t-system tends to swell due to net ionic fluxes from the ECF across the access resistance. However, a stable t-volume is possible when this is offset by a net efflux from the t-system to the cell and thence to the ECF, forming a net ion cycle ECF?t-system ?sarcoplasm?ECF that ultimately depends on Na+/K+-ATPase activity. Membrane properties that maximise this circuit flux decrease t-volume, including PNa(t) > PNa(s), PK(t) < PK(s) and N(t) < N(s) (P, permeability; N, Na+/K+-ATPase density; (t)...