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Purpose: Low-intensity pulsed ultrasound (LIPUS) has been used to stimulate the healing of the fresh fracture, delayed union, and non-union in both animal and clinical studies. Besides, biphasic calcium phosphate ceramic (BCP) is a promising biomaterial for bone repair as it shows favorable biocompatibility, osteoinduction, and osteoconduction. However, scarcity is known about the combined effect of LIPUS and BCP on bone formation. Methods: The combined effect of LIPUS and BCP was studied in a beagle model. Twelve dogs were used. BCP granules without any additions were implanted into bilateral erector spinae muscles. One side is the BCP group, while the counterlateral side is LIPUS + BCP group. Histological and histomorphometric analyses, and quantitative real-time polymerase chain reaction were evaluated. Results: Compared with BCP alone, the LIPUS + BCP showed no advantages in early bone formation. Furthermore, the Notch signaling pathway-related mRNA has no significant difference between the two groups. Conclusions: The preliminary results showed that the BCP, which has intrinsic osteoinduction nature, was an effective and promising material. However, LIPUS has no enhanced effect in BCP induced ectopic bone formation. Furthermore, LIPUS has no effect on the Notch signaling pathway. Whether costly LIPUS could be used in combination with BCP should be a rethink.

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OBJECTIVE: To investigate the cardiovascular effects produced by transthoracic application of low-intensity pulsed ultrasound therapy (LIPUST). METHODS: Three-month-old male Wistar rats (± 300 g, N=16) were randomly allocated in two groups, namely SHAM (control group, faked procedures) and UST (animals treated with LIPUST). These animals, under anesthesia, were instrumented (femoral artery and vein catheterization) for hemodynamic recordings (mean blood pressure [MBP], heart rate [HR]) and blood biochemical profile (lipids, creatine kinase-myocardial band [CK-MB]). Then, LIPUST (spatial average-temporal average [ISATA] 1-MHz, power 0.1 to 1.2 W/cm2, pulsed 2:8 ms, cycle at 30%, for three minutes) was applied to animals from the UST group, externally to their thorax. SHAM animals were equally manipulated, but without application of ultrasound energy. After the hemodynamic and biochemical measurements, animals were sacrificed, and their hearts were mounted in a Langendorff apparatus for coronary reactivity evaluation. Standard histology techniques were employed to analyze the hearts. RESULTS: LIPUST application caused statistically significant reductions in MBP (92±4 vs. 106±1 mmHg) and HR (345±14 vs. 380±17 rpm) when compared with SHAM procedures. UST rats exhibited higher CK-MB levels (318±55 vs. 198±26 U/dL) and lower plasma triglycerides levels (38±7 vs. 70±10 mg/dL) than SHAM animals. Coronary reactivity was not significantly changed by LIPUST. Cardiac histopathology showed an increase in capillary permeability in treated animals when compared with SHAM animals. CONCLUSION: Noninvasive LIPUST induces significant metabolic and hemodynamic changes, including intensity-dependent bradycardia and hypotension, indicating a possible therapeutic effect for cardiac events.

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Abstract Objective: To investigate the cardiovascular effects produced by transthoracic application of low-intensity pulsed ultrasound therapy (LIPUST). Methods: Three-month-old male Wistar rats (± 300 g, N=16) were randomly allocated in two groups, namely SHAM (control group, faked procedures) and UST (animals treated with LIPUST). These animals, under anesthesia, were instrumented (femoral artery and vein catheterization) for hemodynamic recordings (mean blood pressure [MBP], heart rate [HR]) and blood biochemical profile (lipids, creatine kinase-myocardial band [CK-MB]). Then, LIPUST (spatial average-temporal average [ISATA] 1-MHz, power 0.1 to 1.2 W/cm2, pulsed 2:8 ms, cycle at 30%, for three minutes) was applied to animals from the UST group, externally to their thorax. SHAM animals were equally manipulated, but without application of ultrasound energy. After the hemodynamic and biochemical measurements, animals were sacrificed, and their hearts were mounted in a Langendorff apparatus for coronary reactivity evaluation. Standard histology techniques were employed to analyze the hearts. Results: LIPUST application caused statistically significant reductions in MBP (92±4 vs. 106±1 mmHg) and HR (345±14 vs. 380±17 rpm) when compared with SHAM procedures. UST rats exhibited higher CK-MB levels (318±55 vs. 198±26 U/dL) and lower plasma triglycerides levels (38±7 vs. 70±10 mg/dL) than SHAM animals. Coronary reactivity was not significantly changed by LIPUST. Cardiac histopathology showed an increase in capillary permeability in treated animals when compared with SHAM animals. Conclusion: Noninvasive LIPUST induces significant metabolic and hemodynamic changes, including intensity-dependent bradycardia and hypotension, indicating a possible therapeutic effect for cardiac events.

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Introduction: This study evaluated the influence of sonic vibration and thermocycling on the bond strength of fiberglass posts using conventional dual-cured and self-adhesive resin cements. Material and Methods: Ninety-six single-rooted endodontically treated teeth were divided randomly into eight groups according to the cement used (dual-cured or self-adhesive resin cement), use of sonic vibration during post accommodation, and aging conditions (24h in distilled water or 5,000 thermal cycles). The fiberglass posts (White Post DC1, FGM) were cleaned with alcohol, treated with silane and cemented with dual-cured (Allcem Core, FGM) or with self-adhesive resin cement (seT, SDI). For groups in which sonic vibration was used, the posts were accommodated, and sonic vibration was applied for 10 s using a special tip placed on top of the post (Sonic Smart Device, FGM). Pull-out tests were performed after storage in distilled water for 24h at 37°C or after thermocycling (5000 cycles, at 5°C and 55°C). The results were evaluated using three-way ANOVA and Tukey's test (α=0.05). Results: Significant differences were not observed between the bond strengths of dual-cured (87.93±41.81 N) and self-adhesive cement (82.53±41.43 N). Bond strength for the sonic vibration groups (100.36±42.35 N) was significantly higher than for groups without sonic vibration (70.13±34.90 N). There were significant differences between specimens subjected to thermocycling (98.33±39.42 N) and those stored for 24h in distilled water (72.16±39.67 N). Conclusion: It can be concluded that both sonic vibration and thermocycling significantly improved bond strength of fiberglass posts with the two evaluated resin cements.

Introducción: Este estudio evaluó la influencia de la vibración sónica y el termociclado en la fuerza de unión de los postes de fibra de vidrio utilizando cementos de resina autoadhesivos y de curado dual convencionales Material y Métodos: Se dividieron aleatoriamente noventa y seis dientes tratados endodónticamente de raíz única en ocho grupos según el cemento utilizado (cemento de resina de curado dual o autoadhesivo), el uso de vibración sónica durante la acomodación posterior y las condiciones de envejecimiento (24 horas agua destilada o 5.000 ciclos térmicos). Los postes de fibra de vidrio (White Post DC1, FGM) se limpiaron con alcohol, se trataron con silano y se cementaron con cemento de curado dual (Allcem Core, FGM) o con cemento de resina autoadhesivo (seT, SDI). Para los grupos en los que se utilizó vibración sónica, se acomodaron los postes y se aplicó la vibración sónica durante 10 s utilizando una punta especial colocada en la parte superior del poste (Sonic Smart Device, FGM). Las pruebas de extracción se realizaron después del almacenamiento en agua destilada durante 24 horas a 37ºC o después del termociclado (5000 ciclos, a 5ºC y 55ºC). Los resultados se evaluaron mediante ANOVA de tres vías y la prueba de Tukey (α = 0.05). Resultados: No se observaron diferencias significativas entre las resistencias de adhesión del cemento de curado dual (87,93 ± 41,81 N) y el cemento autoadhesivo (82,53 ± 41,43 N). La fuerza de unión para los grupos de vibración sónica (100,36 ± 42,35 N) fue significativamente mayor que para los grupos sin vibración sónica (70,13 ± 34,90 N). Hubo diferencias significativas entre los especímenes sometidos a termociclado (98,33 ± 39,42 N) y los almacenados durante 24 h en agua destilada (72,16 ± 39,67 N). Conclusión: Se puede concluir que tanto la vibración sónica como el termociclado mejoraron significativamente la fuerza de unión de los postes de fibra de vidrio con los dos cementos de resina evaluados.

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Este estudio se realizó con el propósito de analizar el efecto de la aplicación de ondas de USBI sobre la velocidad y distancia de movimiento dentario, y su efecto a nivel histológico en ratas Sprague-Dawley. Veintitrés ratas macho Sprague-Dawley fueron parte del experimento, las que fueron divididas aleatoriamente en tres grupos. Cinco ratas fueron utilizadas como control sin movimiento dentario ortodóncico (MDO), nueve ratas fueron sometidas a una aplicación de fuerza ortodóncica sin aplicación de USBI y nueve fueron sometidas a una aplicación de fuerza ortodóncica con USBI. Estas fuerzas ortodóncicas fueron realizadas entre el aspecto mesio vestibular del primer molar superior izquierdo y el incisivo central superior, traccionando el molar hacia mesial, aplicando una fuerza aproximada de 50 gramos durante 21 días, debido a problemas con la sedación estos dos últimos grupos quedaron compuestos de seis y ocho ratas respectivamente. En el grupo MDO sin USBI, se registró una reducción del espacio entre molares e incisivos de 2 mm. En el grupo MDO con USBI dicha reducción fue de 3.4 mm, siendo esta diferencia estadísticamente significativa. Histológicamente el grupo MDO c/USBI mostró un perímetro vascular y espacios medulares aumentados respecto de los otros grupos, no obstante, no se encontraron diferencias significativas en la cantidad de osteoclastos. Fue posible observar y demostrar cuantitativamente que el USBI es una forma de estimulación mecánica eficiente para la aceleración del MDO sobre un período experimental de 21 días, donde se observaron diferencias significativas entre el grupo control, el grupo MDO sin USBI y el grupo MDO con USBI en la magnitud del movimiento dentario. Se observó una mayor vascularidad en el grupo con USBI, expresando perímetros vasculares de mayor tamaño, esto pudo deberse al efecto estimulatorio del ultrasonido sobre la angiogénesis.

The objective of this study was to analyze the effect of USBI wave application on the speed and distance of dental movement, and its effect at histological level in SpragueDawley rats. In this study twenty-three male Sprague-Dawley rats were randomly divided into three groups. Five rats were used as control without orthodontic tooth movement (MDO), nine rats were subjected to an orthodontic force application without USBI application, and nine were subjected to an orthodontic force application with USBI. The orthodontic forces were performed between the vestibular mesio aspect of the first upper left molar and upper central incisor, pulling the molar mesially, applying an approximate force of 50 grams for 21 days. In light of sedation problems these last two groups were composed of six and eight rats respectively. In the MDO group without USBI, there was a reduction in the space between molars and incisors of 2 mm. In the MDO group with USBI this reduction was 3.4mm, this difference being statistically significant. Histologically, the MDO c / USBI group showed a vascular perimeter and enlarged spinal spaces with respect to the other groups, however, no significant differences were found in the amount of osteoclasts. It was possible to quantitatively demonstrate that USBI is a form of efficient mechanical stimulation for MDO acceleration over an experimental 21-day period, where significant differences were observed in tooth movement between the control group, the group without USBI and the group with USBI. A greater vascularity was observed in the group with USBI, expressing larger vascular perimeters, which could be due to the stimulatory effect of ultrasound on angiogenesis.

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The study of fractures in subsurface is very important since they are, in some cases, the main conduits for hydrocarbon flow in a reservoir. There are many ways to study the behavior of seismic waves in different fracturing conditions, including the use of physical modeling. This method allows, among other approaches, the analysis of the behavior of seismic wave properties in complex fractured media, such as media with orthorhombic symmetry. In this work we performed ultrasonic measurements on fractured physical models with orthorhombic symmetry from which we analyzed the behavior of elastic velocities and anisotropy parameters for different number of fractures. The presented results show the efficiency of the construction methodology used in the study by presenting P- and S- wave velocity values consistent with the theory for an orthorhombic medium. It was observed that for the direction perpendicular to the fracture system the values of P and S-wave velocities were the smallest for each model, and that the velocities decreased as the number of fractures increased in all models. Furthermore, most of the ∊ and γ values show a decreasing behavior as a function of the decreasing number of cracks, being the trend curves of ∊ linear and most of the trend curves of γ quadratic. Additionally, all the ∊ parameters presented a high correlation with the γ parameters for a small number of fractures, lower than 5.

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Abstract The aim of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on the osteogenic differentiation of dental follicle cells (DFCs) in vitro and on the regenerative effects of DFC-OsteoBoneTM complexes in vivo. DFCs were isolated and characterized. In the in vitro study, DFCs were cultured in an osteogenic medium in the presence or absence of LIPUS. The expression levels of ALP, Runx2, OSX, and COL-I mRNA were analyzed using real-time polymerase chain reaction (RT-PCR) on day 7. Alizarin red staining was performed on day 21. The state of the growth of the DFCs that were seeded on the scaffold at 3, 5, 7, and 9 days was detected by using a scanning electron microscope. In our in vivo study, 9 healthy nude mice randomly underwent subcutaneous transplantation surgery in one of three groups: group A, empty scaffold; group B, DFCs + scaffold; and group C, DFCs + scaffold + LIPUS. After 8 weeks of implantation, a histological analysis was performed by HE and Mason staining. Our results indicate that LIPUS promotes the osteogenic differentiation of DFCs by increasing the expression of the ALP, Runx2, OSX, and COL-I genes and the formation of mineralized nodules. The cells can adhere and grow on the scaffolds and grow best at 9 days. The HE and Mason staining results showed that more cells, fibrous tissue and blood vessels could be observed in the DFCs + scaffold + LIPUS group than in the other groups. LIPUS could promote the osteogenic differentiation of DFCs in vitro and promote tissue regeneration in a DFCs-scaffold complex in vivo. Further studies should be conducted to explore the underlying mechanisms of LIPUS.

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In this work, an ultrasound experimental setup was designed to investigate the feasibility of using low-frequency ultrasonic waves as a substitute to reduce the consumption of chemical demulsifiers in the pretreatment of crude oil. The experiments were planned to study the effects of irradiation time, ultrasonic field intensity and initial water content on the efficiency of separation. The results of experiments showed that by selecting a proper irradiation time and field intensity, it is possible to decrease the usage of demulsifiers by 50%. Moreover, a population balance model was proposed to explicate the experimental data. A hybrid coalescence model was developed to determine the frequency of aggregation. The parameters of the model were estimated by linear regression. The parameter estimation was performed using a parallel execution of the particle swarm optimization algorithm. The results of the model showed a decent agreement with the experimental data.

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Os efeitos inativantes da água ozonizada (03 concentração média, 5,2mg/L), das ondas ultra-sônicas(freqüência, 37 kHz), da associação entre ambos, do cloro orgânico a 100 e 200mg/L e do vinagre a 2% e 6%, foram estudados como alternativas aos desinfetantes rotineiros. As amostras foram avaliadas segundo o Número Mais Provável médio de coliformes a 45°C. Isoladamente, o ozônio e o vinagre a 6% apresentaram o melhor efeito sanificante, apresentando reduções respectivas de 95% e 100% em relação ao grupo controle. A associação entre o ozônio e ultra-som, reduziu em 99,6% a carga microbiana. Na concentração de lOOmg/L, o dicloroisocianurato de sódio não apresentou efeito sanificante, porém a 200mglL, a redução foi de 64%. O ozônio promoveu aumento da conservação, entretanto as ondas ultra-sônicas ou a associação entre os processos acelerou o término da vida útil. O vinagre foi o sanificanteque mais comprometeu a vida útil do produto. A redução encontrada foi de 62,2% para o vinagre a2% e 100% para o vinagre a 6%. (AU)

The inactivate effects of ozonated water (03 medium concentration, 5.2mg/L), of ultrasonic waves (frequency, 37 kHz), and of both methods combination, of organic chlorine by 100mg/L and 200mg/L and de vinegar by 2% and 6%, were studied like alternatives to usual disinfectants. The samples were evaluated regarding the More Probable medium Number of coliforms at 45ºC. Among isolated treatments, the ozonated water and de vinegar by 6% were those with the best result, presenting a reduction concerning at 95% and 100%. The association between ozonated water and ultrasonicwaves presented a reduction at 99.6%. The DCIS at 100mg/L, did not present effect over the microorganisms, but at 200mglL, the reduction was at 64%. The ozone produced an increase of conservation, nevertheless, the ultrasonic waves or the association between methods acceleratedthe conclusion of useful life. The vinegar was that one more prejudicial for the useful life, the found reduction was at 62.2% for the vinegar at 2%, and 100%, for the vinegar at 6%. (AU)

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