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1.
Rev. Fac. Odontol. Porto Alegre (Online) ; 62(1): 63-70, jan.-jun. 2021.
Article in English | LILACS, BBO | ID: biblio-1443429

ABSTRACT

Introduction: This study aims to analyze the influence of particles size of sol-gel derived calcium silicate particles in the setting reaction of bioactive endodontic cements. Materials and Methods: Sol-gel derived calcium silicate particles were synthesized and sieved to separate the particles in different sizes: CS400, CS200, and CS100. A commercial MTA (Control) was used as control. The particle size and the specific surface area were assessed by laser diffraction and nitrogen adsorption. The cements were prepared with water as the liquid for the reaction. The setting time was conducted according to ISO 6876, and the setting kinetics was analyzed by Fourier trans-formed infrared spectroscopy (FTIR) at different time points between 120s to 72h. Results: The particle size varied from 9.45µm (CS400 ) to 31.01 (Control). The higher specific surface area valuer reached 15.14g/cm2 in the CS400. The smallest particle sizes, the higher specific surface area, and the lowest setting time were found for CS400 (p < 0.05). Control presented the highest setting time (p < 0.05). The FTIR analyses showed the differences in materials structure over time, with faster hydration and crystallization for CS400. The setting kinetics was slower for Control even when compared to a sol-gel derived group with similar particle size. Conclusion:The route of synthesis and the particle size influences the setting reaction of calcium silicate-based cements. The reduction of particle size for sol-gel derived calcium silicates lead to the acceleration of the setting reaction of the produced bioactive endodontic cement.


Introdução: Este estudo tem como objetivo analisar a influência do tamanho de partículas de silicato de cálcio derivadas de sol-gel na reação de presa de cimentos endodônticos bioativos. Materiais e Métodos: Partículas de silicato de cálcio derivadas de sol-gel foram sintetizadas e peneiradas para separar as partículas em diferentes tamanhos: CS400, CS200 e CS100. Um MTA comercial (Controle) foi usado como controle. O tamanho das partículas e a área superficial específica foram avaliados por difração a laser e adsorção de nitrogênio. Os cimentos foram preparados com água como líquido para a reação. O tempo de presa foi conduzido de acordo com a ISO 6876, e a cinética de presa foi analisada por espectroscopia de infravermelho transformada de Fourier (FTIR) em diferentes pontos de tempo entre 120s a 72h. Resultados: O tamanho de partícula variou entre 9,45µm (CS400) e 31,01 (Controle). A maior área de superfície foi encontrada nas partículas do grupo CS400 (15.14g/cm2). Os menores tamanhos de partícula, a maior área de superfície específica e o menor tempo de presa foram encontrados para CS400 (p < 0,05). O Control apresentou o maior tempo de presa (p < 0,05). As análises de FTIR mostraram as diferenças na estrutura dos materiais ao longo do tempo, com hidratação e cristalização mais rápidas para CS400. A cinética de presa foi mais lenta para Control mesmo quando comparado a um grupo derivado de sol-gel com tamanho de partícula semelhante. Conclusão: A rota de síntese e o tamanho das partículas influenciam a reação de endurecimento dos cimentos à base de silicato de cálcio. A redução do tamanho de partícula para silicatos de cálcio derivados de sol-gel leva à aceleração da reação de pega do cimento endodôntico bioativo produzido.


Subject(s)
Particle Size , Silicate Cement/analysis , Calcarea Silicata , Materials Science , Spectroscopy, Fourier Transform Infrared , Fourier Analysis
2.
Neotrop. ichthyol ; 19(4)2021.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1485609

ABSTRACT

ABSTRACT The genus Cichla is a highly diverse group, with 16 species already described. Externally, some species are very similar and discriminating between them may be very difficult. Nevertheless, discrimination of fish stocks is essential for management purposes. Morphometric analyses of otoliths have been successfully used to distinguish species and fish stocks, especially in marine environments. This study evaluated whether sagittal otolith shape can be used to discriminate among the species Cichla temensis, C. monoculus, and C. orinocensis, as well as within populations of C. temensis in rivers of the Amazon. Shape indices and Fourier coefficients were used to describe the shape of the otoliths. Among the groups of species, the morphology of the sagittal otolith of C. temensis was totally distinct from the species C. monoculus and C. orinocensis. While among populations of C. temensis, individuals from the Negro and Jatapú Rivers were different, regardless of the methods used. These results confirm the ability to differentiate species and populations by using the morphology of otoliths. However, more research is needed to verify the role of genetic versus environmental and biotic effects, and thus be able to explain the discrimination observed in otoliths.


RESUMO O gênero Cichla é bastante diverso, com 16 espécies descritas. Algumas espécies são externamente muito similares e sua discriminação pode ser bastante difícil. Ao mesmo tempo, a discriminação de estoques pesqueiros é essencial para propostas de manejo. Análises morfométricas em otólitos têm sido utilizadas com sucesso para a distinção de espécies e estoques pesqueiros, principalmente em ambientes marinhos. Este estudo avaliou se o formato do otólito sagittal pode ser utilizado para discriminar entre espécies Cichla temensis, C. monoculus e C. orinocensis, bem como dentro de populações de C. temensis em diferentes rios amazônicos. Índices de forma e coeficientes de Fourier foram utilizados para descrever a forma dos otólitos. Dentre as espécies, a morfologia do otólito sagittal do C. temensis mostrou ser totalmente distinta das espécies C. monoculus e C. orinocensis. Enquanto no grupo das populações de C. temensis, os indivíduos dos rios Negro e Jatapú mostraram-se diferentes independente dos métodos utilizados. Esses resultados confirmam a capacidade de diferenciação de espécies e populações através da morfologia dos otólitos. No entanto, são necessárias mais pesquisas para verificar o papel dos efeitos genéticos em comparação aos efeitos ambientais e bióticos para explicar a discriminação observada nos otólitos.

3.
Braz. oral res. (Online) ; 35: e034, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1153609

ABSTRACT

Abstract The objective of this study was to apply elliptic Fourier analysis (EFA) to find shape differences among skeletal growth patterns in both radiographic and tomographic panoramic views, controlling for asymmetry. Lateral and panoramic images were obtained from 350 patients. After screening patients with asymmetric linear and angular values and natural asymmetric hemimandibular shape, 240 patients were included in the study: 48 with tomographic information and 192 with radiographic information. The images were classified according to the mandibular plane angle and the ANB angle. Mandibular contours were digitized on the panoramic images and EFA was performed with 20 harmonics, filtering rotation, translation and size properties. As there were no differences between radiographic and tomographic panoramic mandibular contours and normal distribution was found in all groups, MANOVA was conducted to determine differences using a Hotelling's p-values with Bonferroni correction and an XY graph tool was applied to visualize these differences graphically. A 95% confidence level was used. Significative differences were found among hypodivergent, normodivergent, and hyperdivergent patterns in Class I, II, and III (p < 0.05), located mainly in the symphyseal region. The results of this study suggest that EFA is a useful tool to mathematically analyze mandibular contours and their morphological differences given by facial biotypes. This method could improve the precision of the mandibular prediction models.


Subject(s)
Humans , Mandible/diagnostic imaging , Cephalometry , Fourier Analysis
4.
Rev. saúde pública (Online) ; 53: 55, jan. 2019. tab, graf
Article in English | LILACS | ID: biblio-1014538

ABSTRACT

ABSTRACT OBJECTIVE To examine the effect of seasonality on femoral fracture incidence among people residing in the state of São Paulo, Brazil. METHODS Ecological study based on a consecutive series of 216,348 reports of hospital admissions caused by femoral fractures. A Bayesian statistical model was used for time series analysis, considering the monthly average number of events of femoral fractures per day as a dependent variable. RESULTS Among the female population, significant seasonal effects were observed only for older women, aged 60 years or more. Among younger men (aged less than 20 years) there is not a clear seasonal effect, but among the other age groups there seems to exist a higher number of cases of femoral fractures during the coldest months of the year. CONCLUSIONS In general, more cases of fractures occur during the coldest months of the year; however, men and women have different patterns of incidence according to each age group.


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Femoral Fractures/epidemiology , Seasons , Brazil/epidemiology , Sex Factors , Incidence , Bayes Theorem , Age Factors , Middle Aged
5.
Psychiatry Investigation ; : 474-482, 2015.
Article in English | WPRIM | ID: wpr-48253

ABSTRACT

OBJECTIVE: Hyperactivity is a core symptom of attention-deficit hyperactivity disorder (ADHD), but limited information is available on analysis of activity patterns in this disorder. The aim of the study was to analyze motor activity during daily living in adult patients with ADHD. METHODS: Patients (n=76) from the private psychiatric practice of two of the authors were recruited, and were compared to patients with other psychiatric disorders and to normal controls. Actigraphs were used to record motor activity for six days, with one minute intervals, and data were analysed using linear and non-linear mathematical methods. RESULTS: For short recording periods (300 minutes) the activity levels of ADHD patients do not differ from normal controls, but the autocorrelation (lag 1) is lower and Fourier analysis shows higher power in the high frequency range, corresponding to the period from 2-8 min. During recordings for six days there are no significant differences between ADHD patients and the control groups. The combined and inattentive subgroups differ only in the six days recordings. The Fourier analyses show that the combined type has lower power in the high frequency range, corresponding to the period from 4-8 hours, and in the analysis of rhythms the intra-daily variability is lower, compared to the inattentive type. CONCLUSION: Adult ADHD patients do not show evidence of hyperactivity, but have levels of activity similar to normal controls. However, on several measures ADHD patients display altered activity patterns, indicating that the regulation of motor activity in this disorder is different from controls.


Subject(s)
Adult , Humans , Attention Deficit Disorder with Hyperactivity , Fourier Analysis , Motor Activity
6.
Arq. bras. oftalmol ; 77(6): 345-350, Nov-Dec/2014. tab, graf
Article in English | LILACS | ID: lil-735807

ABSTRACT

Purpose: To compare the results of central corneal thickness (CCT) measurements obtained using optical low-coherence reflectometry (OLCR), Fourier domain optical coherence tomography (FD-OCT), and a Scheimpflug camera (SC), combined with Placido corneal topography. Methods: A total of 25 healthy subjects were enrolled in the present study, and one eye of each subject was included. A detailed ophthalmic examination was performed in all cases following CCT measurements with OLCR, FD-OCT, and SC. The results were compared using an ANOVA test. Bland-Altman analysis was used to demonstrate agreement between methods. Intra-examiner repeatability was assessed by using intraclass correlation coefficients (ICCs). Results: Statistically significant differences were observed between the results of the CCT measurements obtained using the three different devices (p=0.009). Significant correlations were found between OLCR and FD-OCT (r=0.97; p<0.0001), FD-OCT and SC (r=0.91; p<0.0001), and OLCR and SC (r=0.95; p<0.0001). The 95% limits of agreement (LOA) obtained from Bland-Altman plots were from -7.2 μm to 28.7 μm for OLCR versus FD-OCT, from -19.2 μm to 30.4 μm for OLCR versus SC, and from -42.6 to 32.3 μm for FD-OCT versus SC. Intra-examiner repeatability was excellent for each method, with ICCs >0.98. Conclusion: Although the results of CCT measurements obtained from these three devices were highly correlated with one another and the mean differences between instruments were comparable with the reported diurnal CCT fluctuation, the measurements are not directly interchangeable in clinical practice because of the wide LOA values. .


Objetivo: Comparar os resultados de medições de espessura corneana central (CCT ) obtidos com reflectometria óptica de baixa coerência (OLCR), tomografia de coerência óptica de domínio Fourier (FD-OCT ), e uma câmera Scheimpflug (SC), combinada com topografia corneana de placido. Métodos: Um olho de cada de 25 indivíduos saudáveis foram incluídos neste estudo. Um exame oftalmológico detalhado foi realizado em todos os casos após as medidas de CCT com OLCR, FD-OCT, e SC. Os resultados foram comparados por meio do teste ANOVA. Análise de Bland-Altman foi utilizada para demonstrar concordância entre os métodos. A repetibilidade intra-examinador foi avaliada por meio de coeficientes de correlação intraclasse (ICCs). Resultados: Foram observadas diferenças estatisticamente significativas entre os resultados das medidas de CCT obtidas a partir de três dispositivos diferentes (p=0,009). Foram encontradas correlações significativas entre OLCR e FD-OCT (r=0,97, p<0,0001), FD-OCT e SC (r=0,91, p<0,0001), e OLCR e SC (r=0,95; p<0,0001). Os limites de 95% de confiança (LOA) obtidos a partir de gráficos de Bland-Altman foram de -7,2 a 28,7 μm para OLCR contra FD-OCT, de -19,2 a 30,4 μm para OLCR contra SC, e de -42,6 a 32,3 μm para FD-OCT contra SC. A repetibilidade intra-examinador foi excelente para cada método com ICCs>0,98. Conclusões: Apesar de os resultados das medições CCT obtidos a partir destes três dispositivos terem sido altamente correlacionados entre si e as diferenças médias entre os instrumentos serem comparáveis à flutuação relatado da CCT diurna, as medições não são diretamente intercambiáveis na prática clínica em razão da largura dos valores limites de confiança. .


Subject(s)
Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Young Adult , Cornea/anatomy & histology , Corneal Pachymetry/instrumentation , Corneal Pachymetry/methods , Corneal Topography/methods , Tomography, Optical Coherence/methods , Analysis of Variance , Anatomy, Cross-Sectional , Biometry/instrumentation , Biometry/methods , Corneal Topography/instrumentation , Fourier Analysis , Observer Variation , Photography/instrumentation , Reference Values , Reproducibility of Results , Statistics, Nonparametric
7.
Clinical Psychopharmacology and Neuroscience ; : 48-53, 2014.
Article in English | WPRIM | ID: wpr-53117

ABSTRACT

OBJECTIVE: Research of electroencephalograph (EEG) power spectrum and mean frequency has shown inconsistent results in patients with schizophrenic, schizoaffective and bipolar disorders during medication when compared to normal subjects thus; the characterization of these parameters is an important task. METHODS: We applied quantitative EEG (qEEG) to investigate 38 control, 15 schizophrenic, 7 schizoaffective and 11 bipolar disorder subjects which remaine under the administration of psychotropic drugs (except control group). Absolute spectral power (ASP), mean frequency and hemispheric electrical asymmetry were measured by 19 derivation qEEG. Group mean values were compared with non parametrical Mann-Whitney test and spectral EEG maps with z-score method at p < 0.05. RESULTS: Most frequent drug treatments for schizophrenic patients were neuroleptic+antiepileptic (40% of cases) or 2 neuroleptics (33.3%). Schizoaffective patients received neuroleptic+benzodiazepine (71.4%) and for bipolar disorder patients neuroleptic+antiepileptic (81.8%). Schizophrenic (at all derivations except for Fp1, Fp2, F8 and T6) and schizoaffective (only at C3) show higher values of ASP (+57.7% and +86.1% respectively) compared to control group. ASP of bipolar disorder patients did not show differences against control group. The mean frequency was higher at Fp1 (+14.2%) and Fp2 (+17.4%) in bipolar disorder patients than control group, but no differences were found in frequencies between schizophrenic or schizoaffective patients against the control group. Majority of spectral differences were found at the left hemisphere in schizophrenic and schizoaffective but not in bipolar disorder subjects. CONCLUSION: The present report contributes to characterize quantitatively the qEEG in drug treated schizophrenic, schizoaffective or bipolar disorder patients.


Subject(s)
Humans , Antipsychotic Agents , Bipolar Disorder , Electroencephalography , Fourier Analysis , Psychotic Disorders , Psychotropic Drugs , Schizophrenia , Viperidae
8.
The Journal of The Japanese Society of Balneology, Climatology and Physical Medicine ; : 207-215, 2009.
Article in Japanese | WPRIM | ID: wpr-375016

ABSTRACT

<b>Purpose</b><br> Electrodermal activity (EDA) is well known to be influenced by sympathetic activity. Although spa bathing alters autonomic nervous function, the effects of spa bathing on EDA have not been determined. We therefore examined the influence of spa bathng on EDA and autonomic nervous function. <br><b>Method</b><br> When a gold electrode in test solution and another electrode on the palm were connected to a voltmeter and the index finger was inserted into the test solution, the maximum change of potential shown on the voltmeter was considered as EDA. Several kinds of spa water, tap water, refined water and alkaline ion water were used as test solutions. Electric conductivity, pH, oxidation reduction potential (ORP) and temperature were also measured. Five adult women participated in these tests.<br>To examine influences on the autonomic nervous system, Fourier analysis of the RR interval of heart rate was perforrned for three volunteers using electrocardiography before and after bathing in sulfur spa or tap water. <br><b>Results</b><br> EDA displayed an extremely positive correlation to ORP, a weak negative correlation to pH and barely any relationship to electric conductivity of test solutions. Spectrum density at 0.04-0.15 Hz under Fourier analysis (LF) increased after sulfur bathing, but decreased after tap water bathing.<br>Discussion and conclusion : As EDA strongly correlated to ORP of solutions, epidermal cells may generate electric potential by extracellular ORP which may also produce intracellular electric potential altering membrane potential and consequently autonomic nervous functions might be influenced by the changed EDA.<br> Since LF is consider to mainly comprise a parasympathetic component in resting state, the results of LF may indicate that the balance of autonomic nervous activity of the heart becomes more parasympathetic dominant after sulfur bathing and more sympathetic dominant after tap water bathing.<br>From above mentioned, bathing may have an electric influence on the human body by the ORP of bathing water.

9.
Korean Journal of Physical Anthropology ; : 137-148, 2008.
Article in English | WPRIM | ID: wpr-166934

ABSTRACT

Our previous principal component analysis conducting on reference points, lines and angles, and a vectordeveloped polar coordinate system has elucidated that the components of eigenvectors had positive relationships in the curvature of anterior teeth segment, between the protrusion of canines and degree of arch roundness, and in the length-to-width ratio of 62 maxillary dentitions, which were preliminarily classified with reference to the conventional Thompson's morphological descriptions for dental arch forms. In the present study on morphological characters of the maxillary dentitions, we conducted a Fourier analysis on the previously obtained data. We observed that the amplitude of 2nd, 3rd and 4th Fourier harmonics were closely correlated with the length-to-width ratio, curvature of the anterior teeth segment, and the curvilinear contour of maxillary dental arches. In addition, the relationships between previously estimated data and the constant value and the amplitude of the Fourier series were examined by analysis of correlation coefficients (p<0.01). The results of the present study suggest that the morphology of maxillary dentitions consists of three essentials-the length-to-width ratio, the curvature of anterior teeth and the curvilinear contour of dental arches.


Subject(s)
Dental Arch , Dentition , Fourier Analysis , Principal Component Analysis , Tooth
10.
Kampo Medicine ; : 243-249, 1995.
Article in Japanese | WPRIM | ID: wpr-368121

ABSTRACT

In engineering, when the degrce of distortion of the waveform of the signal is expressed numerically, a coefficient called a distortion factor is used. In order to determine whether or not itis possible to quantify the difference in pulse waveforms in terms of a distortion factor, the authors carried out a Fourier analysis of the pulse waves of 74 cases (74 males between 20 and 40 years of age), calculating the distortion factor of these pulse waves. Employing the pulse wave scale devised by Zhaofu Fei et al, the Ping mai, Hua mai and Xuan mai were differentiated by means of the amplitude ratio of the dicrotic notch to the ejection wave. As a result of a comparison between the distortion factors of these three groups, the authors were successful in quantifying the differences between the wave forms in terms of a distortion factor.

11.
Journal of the Japan Society of Acupuncture and Moxibustion ; : 266-271, 1984.
Article in Japanese | WPRIM | ID: wpr-370444

ABSTRACT

Pulse diagnosis has been taking an important part, together with the other diagnostic techniques, for determination of symptoms and treatment of patients with acupuncture. However, the traditional expression of pulse is complicated and subjective, so that the understanding of pulse diagnosis in termes of modern medicine is almost impossible. We tried to objectify the expression of pulse wave.<br>The pulse wave recorded from the six positions on radial artery according to the method described in Chinese Medicine through a force transducer. The recordings were processed for Fourier analysis utilizing a computer system. Characteristics of the pulse wave can be expressed quantitatively as a form of power spectrum of its components. The preliminary results of this study was reported at the 31th annual meeting of the Japan Society of Acupuncture. This time, we report the analysis on the basic pulse waves which have been recognized as negative-positive and imaginaryreal pulses.<br>Method<br>The subjects were normal volunteers of 36 males and 17. females. A force tranducer (Nihon Kohden TF-11S) Equipped with 0.52cm<sup>2</sup> of sensitive area was placed on the radial artery under the pressure ranging from 20 to 550gr. The pulse wave thus recorded was led into the electronic computer (HITAC-20) to obtain the power spectrum of the frequencies.<br>Results<br>It was found that characteristics of the six kinds of pulse waves, i. e., floating-sunken, smooth-leap and slow-fast types, can be represented quantitatively in terms of frequency histogram. Further, a possibility to express so called "complex pulse" in Chinese Medicine by this method is suggested.

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