Natural canal deviation and dentin thickness of mesial root canals of mandibular first molars assessed by microcomputed tomography

Abstract The aim of this study was to assess the centralization and dentin thickness of mesial root canals of the first mandibular molars by microcomputed tomography (micro-CT). Material and methods: Ninety-nine mandibular molars of Vertucci's type IV canals were scanned by micro-CT. The mesiodistal deviation and centroid were assessed, in both mesiobuccal (MB) and mesiolingual (ML) canals, for the apical 4mm and the full canal length. Results: The dentin thickness was similar for both MB and ML canals. The narrowest thickness was in the distal wall of an MB canal (0.07mm), while the widest was found in the mesial wall of an MB canal (2.46mm). In centroid analysis, both the MB and ML canals exhibited deviations when compared to the root centroid, along the full canal length and the apical 4mm. For the MB canal, the mean deviation was 0.83mm (0.02 mm-2.30 mm) for the full canal and 0.18mm (0.01 mm-1.01 mm) for apical 4mm. Similarly, for the ML canal, the mean deviation measured 0.83 mm (0.05mm-3.99mm) for the full canal and 0.21 mm (0.01mm-1.01mm) for the apical 4 mm. Overall, deviations were observed towards the mesial of the roots, with 69% for MB and 57% for ML canals for the full canal, and 51% for MB canals within the 4 mm. The exception was the ML canal, which exhibited a higher deviation towards distal in the apical 4mm, accounting for 52% of cases. The dentin thickness was consistent between the mesial canals of mandibular molars. However, there is no centrality of mesial canals in their roots, with frequent deviation to mesial.

Resumo O objetivo deste trabalho foi avaliar a centralização e a espessura da dentina dos canais radiculares mesiais de primeiros molares inferiores por meio de microtomografia computadorizada (micro-CT). Material e métodos: Noventa e nove molares inferiores com canais tipo IV de Vertucci foram escaneados por micro-TC. O desvio mesiodistal e o centroide foram avaliados para os canais mesiovestibular (MB) e mesiolingual (ML), nos 4mm apicais e em todo o comprimento do canal. Resultados: A espessura da dentina foi semelhante para os canais MB e ML. A espessura mais estreita foi encontrada na parede distal de um canal MB (0,07mm), enquanto a mais larga foi encontrada na parede mesial de um canal MB (2,46mm). Na análise centroide, tanto o canal MB quanto o ML exibiram desvios quando comparados ao centroide da raiz, ao longo de todo o comprimento do canal e nos 4 mm apicais. Para o canal MB, o desvio médio foi de 0,83mm (0,02mm-2,30mm) para canal inteiro e 0,18mm (0,01mm-1,01mm) para o apical de 4mm. Da mesma forma, para o canal ML, o desvio médio mediu 0,83 mm (0,05 mm-3,99 mm) para o canal inteiro e 0,21 mm (0,01 mm-1,01 mm) para os 4 mm apicais. No geral, foram observados desvios em direção mesial das raízes, sendo 69% para canais MB e 57% para canais ML para canal inteiro, e 51% para canais MB dentro dos 4 mm. A exceção foi o canal ML, que apresentou maior desvio para distal nos 4mm apicais, representando 52% dos casos. A espessura da dentina foi consistente entre os canais mesiais dos molares inferiores. Entretanto, não há centralidade dos canais mesiais em suas raízes, com frequente desvio para mesial.

Generando pseudorréplicas, a partir de variables morfométricas reales, para contrastar hipótesis taxonómicas y evolutivas: el caso de un pez ampliamente distribuido en las tierras bajas de la orinoquia venezolana / Generating pseudo-replicates, from real morphometric variables, for contrast taxonomic and evolutionary hypotheses: the case of a widely distributed fish in the lowlands of the Venezuelan Orinoquia

RESUMEN: Con el propósito de evaluar la distintividad morfométrica de cinco poblaciones de Mikrogeophagus ramirezi (Pisces: Cichlidae) de las tierras bajas de la Orinoquia venezolana, se tomaron 14 hitos homólogos a 83 individuos, y se transformaron a variables Procrustes. Se realizó una prueba MANOVA/CVA, pero ésta no funcionó bien, por el bajo número de ejemplares usados, y se decidió ampliar el tamaño de la muestra. Se determinó la distribución probabilística de las variables, que fue normal, después se detectó que las varianzas eran similares. Luego se procedió a generar 100 valores de cada variable, bajo el modelo Y= X + ε, donde Y es el valor a estimar de la variable, X es el valor promedio de esa variable, y ε es el producto de la desviación estándar real multiplicado por valores aleatorios de una distribución normal, para cada variable y población. Esta simulación, se realizó para tres tipos de desviaciones estándar: La de las variables reales, la de valores ponderados simple y con media calculada con bootstrap. Los datos generados fueron validados comparando con los valores reales, y a través de algunas propiedades de ellos, tanto antes, como después de aplicar la prueba MANOVA/CVA. En todas las pruebas, los valores generados no fueron distintos a los valores reales. Usando los valores generados, como sustitutos válidos, se determinó, estadísticamente, que las cinco poblaciones eran morfométricamente diferentes, y candidatas a ser consideradas especies plenas. Por otra parte, se realizó una regresión entre las coordenadas de los centroides de las muestras reales y se comparó con las de los generados, mientras las coordenadas reales se distribuyen sobre una línea recta casi perfecta, y altísimamente correlacionada, las de los valores generados están muy dispersas. Se infiere que esta línea, llamada Línea de Estasis Centroidal, sea una señal filogenética surgida de los datos reales.

SUMMARY: In order to evaluate the morphometric differences of five populations of Mikrogeophagus ramirezi (Pisces: Cichlidae) from the lowlands of the Venezuelan Orinoquia,14 homologous landmarks from 83 specimens were taken and transformed to Procrustes variates. A MANOVA/CVA test was performed, however, this test did not perform well due to the low number of specimens used, and it was decided to increase the sample size. The probabilistic normal distribution for the variables was determined, and variances of these variables were similar. Subsequently, 100 values for each variable were generated, from the model Y= X + ε, being Y the variable value to estimate, X is the real mean value of that variable, and ? is the product between real standard deviate and random values of a normal distribution. This simulation was made for three types of standard deviates: the real variables SD, the prorated values from real variables, and mean bootstrap prorated values. The data generated values were validated with the real data, and some inner properties, both before and after applying the MANOVA/CVA test. In all tests, the values generated were no different from the real ones. Using the generated values as a valid surrogate, it was statistically determined that five populations were different morphometrically, and candidate species. On other hand, a regression between real data coordinates was performed, and compared with the generated data. Whilst the real data coordinates arranged on an almost perfect straight line, and were highly correlated, the generated data ones were dispersedly arranged. This fact, did permit infers that this line, the Stasis Centroid Line, is a phylogenetic signal emerging from the real data.

Effects of postural changes in eye cyclotorsion and pupil centroid shifts on corneal refractive surgery / 中华实验眼科杂志

The main purpose of corneal refractive surgery is not only to improve vision, but also to improve visual quality, which is a higher level of visual ability except vision.At present, most corneal refractive surgeries take the pupil center as the center of examination and treatment, since changes in body position may result in pupil centroid shifts and eye cyclotorsion and postoperative visual quality can be affected by undercorrected astigmatism, induced astigmatism and increased high order aberration that results from eccentric cutting occurring during corneal refractive surgery.The measurement of centroid shifts and eyeball rotation that can be attributed to the change of body position guiding the design of surgery is of great significance to enhance the accuracy of pupil center positioning, improve the safety of surgery and promote the postoperative visual quality.In this article, the relevant literature on the measurement methods of the pupil centroid shifts and ocular cyclotorsion, pupil centroid shifts and ocular cyclotorsion measured by iris recognition technology in response to changes in body position, and the effects of posture-related pupil centroid shifts and ocular cyclotorsion during refractive surgery on postoperative visual quality (postoperative astigmatism, aberration, and modulation transfer function) were reviewed.

Craniofacial geometric morphometrics in the identification of patients with sickle cell anemia and sickle cell trait

ABSTRACT Objective: The aims of this study were to identify the main characteristics regarding the shape and size of the craniofacial region in patients with sickle cell anemia (SCA) and sickle cell trait (SCT) and in unaffected patients using geometric morphometrics and to check the efficiency of this method. Material and Methods: A cross-sectional analytical study of 45 patients (15 in each group) was performed. Lateral radiographs of the skull were used for the analysis. Seventeen landmarks and semilandmarks were placed for the measurements. The Pocrustes analysis of variance (ANOVA), regression analysis, multivariate analysis of variance, canonical variate analysis, Mahalanobis and Procrustes distances and unweighted pair group method with arithmetic mean (UPGMA) clustering were performed. Allometric effects and sex characteristics were not statistically significant (p> 0.05). Results: There were, however, significant differences (p< 0.05) in craniofacial shape among SCA, SCT and unaffected individuals. Those with SCA showed variations in the shape of the external auditory meatus and at the base of the occipital bone, in addition to the mandibular setback and upper incisor inclination, with a tendency towards prognathism. The individuals with SCT exhibited a similar craniofacial shape to those with SCA, but with slighter variations. Moreover, those with SCT were statistically closer in resemblance to unaffected individuals, given that SCT is not regarded as a disease. Conclusion: This demonstrates the efficiency of geometric morphometrics in the categorization of the assessed groups.

Impact of different centroid means on the accuracy of orthometric height modelling by geometric geoid method

Background:Orthometric height, as well as geoid modelling using the geometric method, requires centroid computation. And this can be obtained using various models, as well as methods. These methods of centroid mean computation have impacts on the accuracy of the geoid model since the basis of the development of the theory of each centroid mean type is different. This paper presents the impact of different centroidmeans on the accuracy of orthometric height modelling by geometric geoid method.Methods:DGPS observation was carried out to obtain the coordinates and ellipsoidal heights of selected points. The centroid means were computed with the coordinates using three different centroid means models (arithmetic mean, root mean square and harmonic mean). The computed centroid means were entered accordingly into a Microsoft Excel program developed using the Multiquadratic surface to obtain the model orthometric heights at various centroid means. The root meanssquare error (RMSE) index was applied to obtain the accuracy of the model using the known and the model orthometric heights obtained at various centroid means.Results:The computed accuracy shows that the arithmetic mean method is the best among the three centroid means types.Conclusions:It is concluded that the arithmetic mean method should be adopted for centroid computation, as well as orthometric height modelling using the geometric method

Development and validation of RP-HPLC method for pitavastatin calcium in bulk and formulation using experimental design

The optimization of HPLC method involves several variables whose influence has been widely studied. However, inmost of the cases, only process variables are taken into account. In this work, the influence of mixture compositionon peak quality parameters of Pitavastatin calcium in bulk and tablet dosage form has been studied using a mixturesimplex design. A simplex centroid design with axial points in a pseudo-component representation was generated fromthe pure mixture components. Twelve ternary mixture mobile phases corresponding to augmented design points weretested to separate the drug in sample. The statistical analysis was performed to generate the polynomial equation foreach response. The desirability approach was used to determine the optimal mobile phase composition. Furthermore,the method was validated as per the ICH guidelines using specificity, linearity, accuracy, precision, sensitivity, systemsuitability, and robustness. The results of experimental design were statistically tested for full and in portion to getbest fitted model which accurately describe changes in the proportion of these solvents in the mobile phase close to theregion of optimal peak quality. The method demonstrated optimum chromatographic separation with isocratic elutionof the mobile phase containing a mixture of acetonitrile-water (pH 3.0)-tetrahydrofuran (43:55:02, v/v/v) with a flowrate at 1.0 ml/minute. Design of experiment optimization strategy is a powerful tool to acquire the maximum qualitydata while performing minimum number of experiments. The mobile phase composition was successfully optimizedusing simplex centroid mixture design with desirability approach. Additionally, developed method can be appliedfor routine quantitative analysis of Pitavastatin calcium in bulk and tablet dosage form as it was found to be simple,sensitive, and robust.

Densidad, idoneidad ambiental y nicho ecológico de cuatro especies de felinos americanos (Carnivora: Felidae)

Varias de las especies silvestres de la familia Felidae se encuentran en riesgo y el tamaño poblacional es uno de los parámetros ecológicos más importantes para determinar acciones efectivas de conservación. El tamaño poblacional está determinado por diferentes factores, tanto bióticos como abióticos, que en conjunto satisfacen los requerimientos de los individuos para sobrevivir y reproducirse, permitiendo la permanencia de las especies a través del tiempo. Debido a que el tamaño poblacional de una especie no es homogéneo a lo largo de su distribución, se han formulado varias hipótesis para explicar sus variaciones. Una propuesta considera que las poblaciones más grandes se ubican en las regiones con mayor idoneidad ambiental y el número de individuos decrece hacia las menos favorables. Otra hipótesis considera que el tamaño poblacional está relacionado con la estructura interna del nicho ecológico, en donde las poblaciones más grandes están ubicadas en el centroide del nicho y el tamaño declina conforme aumenta la distancia a éste. El objetivo de este estudio fue evaluar la relación de la abundancia poblacional con la idoneidad ambiental y el nicho ecológico en cuatro especies de felinos silvestres de América. La densidad de Lynx rufus (lince) se correlacionó positivamente con el índice de idoneidad ambiental, la mayor densidad de Panthera onca (jaguar) se ubicó en regiones cercanas al centroide del nicho, mientras que las densidades poblacionales de Leopardus pardalis (ocelote) y de Puma concolor (puma) no se ajustaron a las predicciones de ninguna de las dos hipótesis. La relación entre densidad de felinos con las características ambientales puede ser especie-específica y no seguir un patrón generalizado.

Several wild species of the family Felidae are at risk, and population size is one of the most important ecological parameters to determine conservation actions. Population size is influenced by different biotic and abiotic factors that satisfy the requirements of the species to survive and reproduce, allowing the permanence of the species through time. Because population size is not homogeneous throughout the distribution, there are several hypotheses to explain their variations. One proposal considers that more abundant populations are located in regions with environmentally suitability, and population size decreases towards the less favorable ones. Another hypothesis considers that the population size is related to the internal structure of the ecological niche, where the largest populations are located in the centroid of the niche, and the size declines as the distance to this centroid increase. The objective of this study was to evaluate the relationship between population abundance, environmental suitability and ecological niche in four wild felids species of America. The density of Lynx rufus (bobcat) was correlated positively with the environmental suitability index, the highest density of Panthera onca (jaguar) was located in regions near the centroid of the niche, while the population densities of Leopardus pardalis (ocelot) and Puma concolor (cougar) did not conform to the predictions of either of the two hypotheses. The relationship between feline density and environmental characteristics was species-specific, with no general pattern.

Kidney tumor segmentation in ultrasound images using adaptive sub-regional evolution level set models / 生物医学工程学杂志

Kidney tumor is one of the diseases threatening human health. Ultrasound is widely applied in kidney tumor diagnosis due to its high popularization, low price and no radiation. Accurate segmentation of kidney tumor is the basis of precise treatment. Kidney tumors often grow in the middle of cortex, so that segmentation is easy disturbed by nearby organs. Besides, ultrasound images own low contrast and large speckle, leading to difficult segmentation. This paper proposed a novel kidney tumor segmentation method in ultrasound images using adaptive sub-regional evolution level set models (ASLSM). Regions of interest are firstly divided into subareas. Secondly, object function is designed by integrating inside and outside energy and gradient, in which the ratio of these two parts are adjusted adaptively. Thirdly, ASLSM adapts convolution radius and curvature according to centroid principle and similarity inside and outside zero level set. Hausdorff distance (HD) of (8.75 ± 4.21) mm, mean absolute distance (MAD) of (3.26 ± 1.69) mm, dice-coefficient (DICE) of 0.93 ± 0.03 were obtained in the experiment. Compared with traditional ultrasound segmentation method, ASLSM is more accurate in kidney tumor segmentation. ASLSM may offer convenience for doctor to locate and diagnose kidney tumor in the future.

Vector analysis and comparison of surgically induced astigmatism after coaxial phacoemulsification with 2.2-and 2.8-mm clear corneal incisions / 眼科新进展

Objective To evaluate the surgically induced astigmatism (SIA)caused by coaxial phacoemuisification and intraocular lens (IOL) implantation with different clear corneal incision.Methods Clinical data of 97 patients 97 eyes underwent phacoemulsification and IOL implantation with 2.2 mm (2.2 mm group,44 eyes) or 2.8mm (2.8 mm group,53 eyes) clear corneal incisions were retrospectively reviewed.The corneal curvature were measured before and four weeks after the surgery.Then SIA were calculated,followed by analysis of the differences in mean SIA and centroid SIA between the 2.2 mm and 2.8 mm groups.Results At 4 weeks after surgery,the centroid and mean SIA of the 2.8 mm group was (0.234 ± 0.423) D@105° and (0.552 ±0.349) D,respectively;the corresponding data was (0.174 ± 0.464) D@104° and (0.582 ±0.392) D in the right eyes,and (0.272 ±0.382)D@106° and (0.545 ±0.300) D in the left eyes,respectively.At 4 weeks after surgery,the centroid and mean SIA of the 2.2 mm group was (0.108 ±0.417)D@98°and (0.506 ±0.362) D,respectively;the corresponding data was (0.145 ±0.404)D@81° and (0.5182 ±0.332)D in the right eyes,and (0.127 ± 0.418) D@120° and (0.516 ± 0.418) D in the left eyes,respectively.There was no significant difference in centroid SIA and mean SIA,centroid SIA and mean SIA of the right and left eyes,as well as both eyes between the two groups (all P＞0.05);Atotal of 47 patients (48.5％) had SIA greater than 0.5 D,and 28 patients (52.8％) were in the 2.8 mm groups,including 12 patients (22.6％) in the right eyes and 16 patients (20.5％) in the left eyes;as well as 19 patients (43.2％) in the 2.2 mm group,including 10 patients (22.7％) in the right eyes and 9 patients (20.5％) in the left eyes.There was no significant difference in the proportion of SIA greater than 0.5 D and the proportion of SIA between the left and right eyes greater than 0.5 D between the two groups (all P ＞ 0.05).Conclusion The mean SIA and centroid SIA are not statistically different in the 2.2 mm group than in the 2.8 mm group,but SIA were more stable in the 2.2 mm group than in the 2.8 mm group.The axis of the SIA were closely related to the position of the incisions,which were the vertical direction of the incisions.

Fluctuating asymmetry in Apis mellifera(Hymenoptera: Apidae) as bioindicator of anthropogenic environments / Asimetría fluctuante en Apis mellifera (Hymenop-tera: Apidae) como bioindicador de ambientes antropo-génicos

The successful distribution of A. melliferais due to their ability to adjust to seasonal variations, considerable control over their internal physical environment and exploration of different resources. However, their populations have experienced different forms and levels of environmental pressure. This research aimed to verify the phenotypic plasticity in both size and shape of wings in A. melliferausing fluctuating asymmetry, based on geometric morphometrics from apiaries located in sites with high and low levels of anthropization. We sampled 16 locations throughout all five geographic regions of Brazil. At each site, samples were collected from 20 beehives installed in apiaries: 10 installed near high anthropogenic environments (Cassilàndia - MS, Fortaleza - CE, Maringá - PR, Aquidauana - MS, Rolim de Moura - RO, Riachuelo - SE, Ubirata - PR and Piracicaba - SP), and 10 in sites with low levels of human disturbance (Cassilàndia - MS, Itapiúna CE, Uniao da Vitoria - PR, Aquidauana - MS, Rolim de Moura - RO, Pacatuba - SE, Erval Seco - RS, Rio Claro - SP). A sample of 10 individuals was taken in each hive, totaling 200 per location, for a total of 1 600 individuals. We used fluctuating asymmetry (FA) in size and shape of the forewing through geometric morphometrics. The FA analysis was conducted in order to check bilateral differences. The indexes of size and shape were submitted to analysis of variance (ANOVA), where the characters evaluated were used as factors to verify the size and shape differences. The results indicated an asymmetry on the shape of the wing (P < 0.001) but no asymmetry was observed on wing size. Considering FA as an environmental response and high and low impacted areas as a fixed factor, we observed significant differences (P < 0.05). The results for the wing shape in A. melliferademonstrated that this feature undergoes more variation during ontogeny compared to the variation in size. We concluded that bee samples collected from colonies with higher levels of human disturbance had higher wing-shape asymmetry; the variation of fluctuating asymmetry in the wing shape of honeybees can be used as an indicator of the degree of environmental anthropization.

La distribución exitosa de A. melliferase debe a su capacidad para adaptarse a las variaciones estacionales, controlar considerablemente su ambiente físico interno y por la exploración de recursos. Sin embargo, sus poblaciones experimentan diferentes formas y niveles de presión ambiental. Esta investigación evaluó colmenares, ubicadas en entornos con distintos niveles de antropización. Ambientes considerados altamente antropogénicos fueron escogidos: áreas urbanas, agrícolas con aplicaciones de insecticidas, y las industrias con grandes áreas (regiones con altos índices de contaminación). Por otra parte, los entornos considerados con bajos niveles de perturbación humana fueron elegidos: áreas de preservación permanente de los bosques restantes (Mata Atlántica, Planalto, Cerrado), áreas ribereñas o reservas ecológicas. Se muestrearon 16 localidades que abarcan las cinco regiones del Brasil. Estamos utilizando la asimetría fluctuante desde el tamaño y la forma del ala anterior por técnicas de morfometría geométrica. En cada sitio, las muestras se obtuvieron de las 20 colmenas instaladas en los colmenares: 10 instalados cerca de entornos altamente antropogénicos (Cassilándia - MS, Fortaleza - CE, Maringá - PR, Aquidauana - MS, Rolim de Moura - RO, Riachuelo - SE, Ubirata - PR y Piracicaba - SP) y 10 en sitios de bajo nivel de perturbación humana (Cassilándia - MS, ItapiúnaCE, Uniao da Vitória - PR, Aquidauana - MS, Rolim de Moura - RO, Pacatuba- SE, Erval Seco - RS, Rio Claro - SP). Los índices de tamaño y forma fueron sometidos a análisis de varianza (ANOVA), donde se utilizaron los caracteres evaluados como factores, para verificar las diferencias de tamaño y forma. La asimetría de análisis fluctuante (AF) se llevó a cabo con el fin de comprobar las diferencias bilaterales. Los resultados indican la existencia de la asimetría de la forma del ala (P < 0.001), pero no se observó asimetría del tamaño del ala. Considerando AF como respuesta ambiental y áreas de alto y bajo grado de alteración humana como factor fijo, observamos diferencias significativas (P < 0.05). Los resultados, para la forma de ala de la A. mellifera,muestran que esta característica se somete a más variación durante la ontogenia en comparación con la variación en el tamaño. Llegamos a la conclusión de que las colonias de abejas recogidas en ambientes con niveles más altos de la perturbación humana tienen una mayor asimetría en forma de ala, por lo que la asimetría fluctuante en forma de alas de las abejas puede ser utilizada como un indicador del grado de antropización del medio ambiente.

Application of drug release model in design of tacrolimus sustained-release pellets prescription / 中国药学杂志

OBJECTIVE: To design tacrolimus sustained-release pellets formula by surface degradation and erosion model, and improve the design accuracy and pertinence. METHODS: The relationship between the prescription and the surface degradation rate constant K was determined by simplex centroid design. The relationship between dissolution prediction and formulation was established and used to direct the formulation design according to the requirements of the expected dissolution. The dissolution profiles obtained by the model prediction and actual experiment were compared through hot-melt coating technology. RESULTS: The dissolution profile similarity factor f2 was over 75 between the measured and predicted dissolution profiles, and the single point error of dissolution was below 5%. CONCLUSION: Using the established model, the formula of tacrolimus sustained-release pellets can be quickly and accurately designed according to the dissolution requirement.

Extraction of flavonoids from Tagetes patula: process optimization and screening for biological activity

The flowers of Tagetes patula L., Asteraceae, commonly known as French marigold, are used in folk medicine as an antiseptic, diuretic, blood purifier and insect repellent. This study was conducted to optimize the extraction process through the biomonitoring of flavonoids, using a statistical mixture simplex-centroid design, to evaluate the effect of the solvents water, ethanol and acetone, as well as mixtures of these solvents, assessed by the total flavonoid content. The extracts were tested for dry residue, radical scavenging activity, chromatographic profile, and larvicidal activity. The acetone extract had the highest total flavonoid content, 25.13 ± 1.02% (4.07%); and the best radical scavenging activity, with IC50 of 15.74 μg/ml ± 1.09 (6.92%), but with lower dry residue, 6.62 ± 1.33% (20.10%). The water extracts showed higher levels of dry residue, but lower total flavonoid content and radical scavenging activity than the acetone extract. The positive correlation between the total flavonoid content and radical scavenging activity of the extracts showed that flavonoids contribute significantly to the antioxidant capacity. The statistical mixture design allowed us to optimize the extraction of flavonoids from flowers of T. patula, with acetone as the best extraction solvent. Preliminary studies on the biological activity of the optimized extracts demonstrated a larvicidal effect of the acetone extract on Aedes aegypti mosquitoes.

Latitudinal gradient effect on the wing geometry of Auca coctei (Guérin)(Lepidoptera, Nymphalidae)

Latitudinal gradient effect on the wing geometry of Auca coctei (Guérin) (Lepidoptera, Nymphalidae). When the environmental conditions change locally, the organisms and populations may also change in response to the selection pressure, so that the development of individuals may become affected in different degrees. There have been only a few studies in which the patterns of wing morphology variation have been looked into along a latitudinal gradient by means of geometric morphometrics. The aim of this work was to assess the morphologic differentiation of wing among butterfly populations of the species Auca coctei. For this purpose, 9 sampling locations were used which are representative of the distribution range of the butterfly and cover a wide latitudinal range in Chile. The wing morphology was studied in a total of 202 specimens of A. coctei (150 males and 52 females), based on digitization of 17 morphologic landmarks. The results show variation of wing shape in both sexes; however, for the centroid size there was significant variation only in females. Females show smaller centroid size at higher latitudes, therefore in this study the Bergmann reverse rule is confirmed for females of A. coctei. Our study extends morphologic projections with latitude, suggesting that wing variation is an environmental response from diverse origins and may influence different characteristics of the life history of a butterfly.

Influencing factors for eye cyclotorsion and pupil centroid shift during LASIK / 眼科

Objective To investigate the influencing factors for eye cyclotorsion and pupil centroid shift during LASIK.Design Non-controlled retrospective case series.Participant 131 patients (262 eyes) with myopia received bilateral LASIK.Methods Eye cy- clotorsion and pupil centroid shift were measured with Custom Vue~(TM) software during operation and compared with age,gender,right or left eye,flap-making method,spherical equivalent (SE),pupil diameter before and during operation.Main Outcome Measures The de- gree of eye cyclotorsion and distance of pupil centroid shift during LASIK.Results The mean eye cyclotorsion during LASIK was 3.07??2.07?(0?-8.6?).The mean pupil centroid shift was 0.33?0.14 mm (0.04-0.51 mm).The eye cyclotorsion was relevant to preoperative pupil size,difference of pupil size before and during operation,and preoperative SE (r=0.188,0.156,0.130,all P7.0 mm was higher than that of with pupil diameter≤7.0mm (3.35??2.17?,2.71??1.89?,P=-0.014).Pupil centroid shift was higher in fight eyes than that in left eyes (0.39?0.12 mm,0.28?0.13 mm,P=0.000).Conclu- sion Eye cyclotorsion and pupil centroid shift during LASIK can be measured with Custom Vue~(TM) system.The eye cyclotorsion may be influenced by the preoperative pupil size.The pupil centroid during LASIK was more significant in the right eyes than in the left eyes.

A Triple Level Registration Strategy of Medical Image Based on Mutual Information / 航天医学与医学工程

Objective To further solve the mutual restricted problems among precision, speed and disregistrated rate of registration algorithm based on mutual information (MI). Methods A new strategy on the search of registration parameters, a triple level registration strategy, was proposed. It searched the translation parameters and the rotation parameters respectively. Based on analyzing the advantage and limitation of MI-based registration, Euclid closeness of Fuzzy theory was introduced into the process of the triple level registration. Results The computer simulation results demonstrated that the proposed registration method, on the condition of retaining the same precision, improved both the speed (step numbers and registration time) and the disregistrated rate. Conclusion The proposed triple level registration strategy is a registration strategy to be able to harmonize precision, speed and disregistrated rate effectively.

Visualizational Investigation on Width of Pulse Tracing / 中国中医药信息杂志

Objective To study the relationship among the area of transverse section of radial artery, the major axis length of the ellipse with same centroid as transverse section, the maximum centroid displacement in the direction parallel with skin surface in a cardiac cycle and width of pulse tracing. Methods ECG, pressure phygmograms and ultrasound images of transverse section of radial artery of 40 patients with different width of pulse tracing and 20 healthy persons were collected synchronously with a new-type sphymograph. On the basis of images analysis with MATLAB 7.0.1, image characteristics of transverse section of radial artery and centroid motion locus of pulse tracings with different width in a cardiac cycle were observed and analyzed. Results Between pulse tracings with different width, there were significant differences in the area of transverse section of radial artery, the major axis length of the ellipse with same centroid as transverse section and the maximum centroid displacement in the direction parallel with skin surface in a cardiac cycle. Conclusions The mean, maximum and minimum value of the area of transverse section and the major axis length of ellipse and the maximum centroid displacement can be used to discriminate width of pulse tracing.

Kyphotic Angle Measurement Accuracy for Vertebral Osteoporotic Compression Fracture: Reliable Method for Kyphotic Angle Measurement

OBJECTIVE: Having a reliable and reproducible measurement technique to measure the sagittal contour in vertebral fractures is paramount to clinical decision making. This study is designed to determine the most reliable measurement technique in osteoporotic vertebral compression fracture. METHODS: Fifteen lateral radiographs of thoracic and lumbar fractures were selected and measured on two separate occasions by three spine surgeons using six different measurement techniques (Centroid, Harrison Posterior Tangent Methods and 4 different types of modified Cobb method). The radiograph quality was assessed and the center beam location was determined. Statistical analysis including ANOVA for repeated measures was carried out using the SAS software (v 8.0). RESULTS: The inter and intraobserver variance of the Cobb method 4 and Harrison posterior tangent method were significantly lower than the other four methods. The intraobserver correlation coefficients were the most consistent using the Cobb method 4 (0.982), which was followed by the Harrison posterior tangent (0.953) and Cobb methods 1 (0.874). The intraobserver agreement (% of repeated measures within 5 degrees of the original measurement) ranged from 42% to 98% for each technique for all three observers, with the Cobb method 4 showing the best agreement (97.8%) followed by the Harrison posterior tangentmethod (93.7%). CONCLUSION: The Cobb method-4 and Harrison posterior tangent methods, when applied to measuring the kyphosis, are reliable and have a similar small error range. The Cobb method 4 shows the best overall reliability. However, the centroid method and Cobb method using a fractured endplate do not produce an accurate result due to inter and intraobserver differences in determining the baseline.