Control of thermal damage in grinding by digital signal processing of raw acoustic emission

Grinding process is usually the last finishing process of a precision component in the manufacturing industries. This process is utilized for manufacturing parts of different materials, so it demands results such as low roughness, dimensional and shape error control, optimum tool-life, with minimum cost and time. Damages on the parts are very expensive since the previous processes and the grinding itself are useless when the part is damaged in this stage. This work aims to investigate the efficiency of digital signal processing tools of acoustic emission signals in order to detect thermal damages in grinding process. To accomplish such a goal, an experimental work was carried out for 15 runs in a surface grinding machine operating with an aluminum oxide grinding wheel and ABNT 1045 e VC131 steels. The acoustic emission signals were acquired from a fixed sensor placed on the workpiece holder. A high sampling rate acquisition system at 2.5 MHz was used to collect the raw acoustic emission instead of root mean square value usually employed. In each test AE data was analyzed off-line, with results compared to inspection of each workpiece for burn and other metallurgical anomaly. A number of statistical signal processing tools have been evaluated.

Powder processing and In Vivo evaluation of a titanium porous coating implant

The processing of titanium porous coatings using powder metallurgy technique to achieve a porous structure that allows osseointegration with bone tissue was discussed. The porous microstructure exhibited micropores and interconnected macropores with size ranges that allowed bone ingrowth. The macropores in the coatings were originated from the binder evaporation while the micropore was related with the porous titanium powder and the low compaction pressure used. The in vivo evaluation indicated that osseointegration had occurred between the bone and porous material.

Toxoplasma gondii in semen of experimentally infected swine

Eight reproductive boars were divided into three groups and inoculated with Toxoplasma gondii [GI (n=3) 1.5×104 oocysts strain P; GII (n=3) 1.0×106 tachyzoites strain RH; and GIII (n=2) non-inoculated control]. Clinical, hematological, parasitemia and serological tests and studies of the parasite in the semen through bioassay and PCR, and in reproductive organs (Bioassay and immunohistochemical analyses) were conducted to evaluate the toxoplasmic infection. Blood and semen were collected on day -2, -1, 1, 3, 5, 7, 9, 11, 14 and weekly up to 84 days post-inoculation (DPI). No clinical or hematimetric alteration was observed in the boars. Parasitemia was detected in one boar inoculated with oocysts at the 7th DPI and in another boar infected with tachyzoites (GII) at the 3rd and 49 th DPI. Serological tests revealed antibodies against T. gondii in animals inoculated with oocysts or tachyzoites at the 7th DPI with dilutions of 1:256 and 1:64, which reached peaks of 1:4096 at day 11 and 9, respectively. The bioassays revealed the presence of the parasite in semen samples of a boar inoculated with oocysts (GI) at 3, 49 and 56 DPI and from two boars infected with tachyzoites (GII), one animal at 5 and two animals at 49 days DPI. Mice inoculated with semen from the control group (GIII) remained serologically negative. PCR analysis showed T. gondii DNA in the semen of Boar 1 and Boar 3 inoculated with tachyzoites and oocysts, respectively. The immunohistochemical tests showed T. gondii in the reproductive organs of Boar 1 and Boar 2, inoculated with tachyzoites and oocysts, respectively. These findings suggest the possible occurrence of venereal transmission of T. gondii in swine.

Border detection in digital images: An approach by fuzzy numbers

The purpose of this paper is to introduce a new approach for edge detection in gray shaded images. The proposed approach is based on the fuzzy number theory. The idea is to deal with the uncertainties concerning the gray shades making up the image, and thus calculate the appropriateness of the pixels in relation to an homogeneous region around them. The pixels not belonging to the region are then classified as border pixels. The results have shown that the technique is simple, computationally efficient and with good results when compared with both the traditional border detectors and the fuzzy edge detectors. © 2007 IEEE.

Use of fibrin glue derived from snake venom in the repair of deep corneal ulcers - Experimental study in dogs (Canis familiaris, Linnaeus, 1758)

Fibrin glue has been researched as an alternative method for tissue synthesis and is known for its capability to promote hemostasis at the application site, good approximation of wound edges and fast healing. The current study consisted in the application of fibrin glue derived from snake venom as treatment for experimental corneal ulcers. Twenty-one dogs had their corneas experimentally prepared through lamellar keratectomy (of standardized diameter and depth). Animals were divided into seven groups of three animals each. Six experimental groups were periodically evaluated and collection was carried out on the 1st, 3rd, 7th, 15 th, 30th and 60th post-operative days, whereas one control group was evaluated throughout the experiment. Analyses consisted in the clinical evolution and in the histopathological study of all operated on eyes. Results indicated that fibrin glue was efficient in repairing keratectomy wounds in dogs and contributed to an earlier healing phenomenon, avoiding edema formation and keeping corneal clearness. The use of fibrin glue derived from snake venom showed to be easy to apply, feasible with animal models and of low cost, avoiding the lesion progress and allowing fast and appropriate corneal healing.

BMP implant associated with platelet-rich plasma in orbit fracture repair

Purpose: To evaluate a bone morphogenetic protein (BMP) implant with and without platelet-rich plasma (PRP), which is supposed to accelerate fracture consolidation in the orbit fracture treatment. Methods: Thirty-six white rabbits were subjected to orbital fracture and treated in three groups: BMP implant fracture repair (G1), BMP plus PRP implant fracture repair (G2), and fracture and spontaneous repair (G3). The animals were sacrificed at 7, 30, 90, and 180 days after surgery. A radiology evaluation was carried out on the 7th day after the fracture and at the sacrifice moments. After the animals' death, the orbital content material was removed and prepared for morphological and morphometric analysis. Results: Radiology suggested intramembranous and progressive cavitation and ossification without a reduction in implant size and with signs of calcium deposition; these events were confirmed by histological analysis, which showed a lymphomononuclear inflammatory reaction in G1 and G2, more intense 7 days after surgery and reducing after 30 days. Associating PRP with BMP did not accelerate bone induction. Conclusion: BMP implant promotes bone induction, integration at fracture site, scarce inflammatory reaction, and may be a good alternative in orbit fracture reconstruction. The addition of PRP to the BMP plate did not accelerate the resolution, and its use is not necessary. Copyright © Informa Healthcare USA, Inc.

Foetal echoencephalography and Doppler ultrasonography of the middle cerebral artery in canine foetuses

Objectives: This study aimed to evaluate the characteristics of the brain and vascular indicesof the middle cerebral artery of canine foetuses. Methods: Twenty-five bitches were selected. Tissue development, echogenicity, echotexture and brain echobiometric data were studied, and the major structures were identified between the 5th and 8th gestational weeks. The area and volume of the brain mass (BMA and BMV), cranial area and volume (AC and VC), brain mass index (BMI) and brain volume index (BVI) were determined. A single ultrasound examination was performed during each studied week (6th, 7th and 8th). Doppler ultrasonography was performed to assess the maximum and minimum velocity, resistance and pulsatility index of middle cerebral artery of the foetuses. Results: Echoencephalography was performed to evaluate the morphological characteristics of the central nervous system. Cerebral echobiometry indicated an increase in area and volume of the hemispheres and cranium (P<0·001) but no changes in BMI or BVI over the gestational period studied. Doppler ultrasonography identified increases in peak systolic velocity (P=0·0188) and end diastolic velocity (P=0·0274) and decreases in resistance index (P=0·0002) and pulsatility index (P<0·001). Clinical Significance: Echoencephalography and spectral Doppler ultrasonography of the middle cerebral artery in canine foetuses might be a useful technique for prenatal care. © 2013 British Small Animal Veterinary Association.

Zinc sulphate administered by transdermal iontophoresis improves breaking strength of surgical wounds in skin of alloxan-induced diabetic rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aquatic Exercise is as Effective as dry Land Training to Blood Pressure Reduction in Postmenopausal Hypertensive Women

Background and Purpose: The evidence of the benefits from regular physical activity to hypertensives is based on dry land training studies. Therefore, the aim of this study is to compare the effect of aquatic exercise with dry land training on hypertensive women. Methods: This is a randomized controlled study with 52 post-menopausal hypertensive women. The patients were randomly allocated in three groups: water aerobic training group (n=19), dry land aerobic training group (n=19) and a non-intervention control group (n=14). The training protocol was performed by 12weeks. Results: There were no differences among the three groups concerning basal blood pressure (BP) and biochemical variables. In water group, there was a statistically significant reduction of systolic BP from 136±16mmHg at zero week to 124±18mm Hg at 11th week and 124±15mmHg at 12th week. In dry land training group, there was a statistically significant reduction of systolic BP from 138±15mmHg at zero week to 125±10mmHg at 7th week, 127±10mmHg at 10th week and 126±9mmHg at 12th week. The control group presented no change in any of the assessed variables. No changes were carried out in any antihypertensive medications during study. Discussion: This is a randomized controlled study that demonstrates the antihypertensive efficacy of aerobic aquatic exercise. © 2013 John Wiley & Sons, Ltd.

Características bioquímicas e microbiológicas do biofilme dentário formado in situ sobre materiais que contêm flúor ou fosfato de cálcio amorfo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conditioned food aversion to Ipomoea carnea var. fistulosa induced by Baccharis coridifolia in goats

Baccharis coridifolia é uma planta tóxica que possui forte poder aversivo em ruminantes. Os objetivos deste trabalho foram induzir aversão condicionada a Ipomoea carnea avar. fistulos em caprinos utilizando B. coridifolia como agente aversivo e comparar a eficiência desta aversão com a aversão induzida por cloreto de lítio (LiCl). Treze cabras foram divididas em dois grupos: o Grupo 1 com seis cabras foi avertido com 175mg/kg de peso corporal (pc) de LiCl e o Grupo 2, com sete cabras, foi avertido com 0,25g/kg de pc de B. coridifolia seco. Todas as cabras foram avertidas no dia 1 logo após a ingestão de I.carnea. A aversão foi repetida nos dias 2, 3 e 7 nos caprinos que ingeriram qualquer quantidade de I. carnea, utilizando-se o mesmo procedimento do dia 1. Os caprinos de ambos os grupos foram desafiados nas baias nos dias 23 e 38 após o último dia da aversão e desafiados na pastagem nos dias 11, 15, 18, 20, 22, 25, 27 e 29 após o último dia da aversão. Posteriormente os caprinos foram desafiados a cada 15 dias na pastagem até o 330º dia após o último dia da aversão (7º dia). Duas cabras do Grupo 1 ingeriram I. carnea no primeiro dia do desafio na pastagem, quatro dias após o ultimo dia da aversão nas baias. Além disso, outra cabra do mesmo grupo reiniciou a ingestão da planta no 18º dia e outras duas no 20º dia. Uma cabra do Grupo 1 que nunca havia ingerido a planta após a aversão morreu no 55º dia. Uma cabra do Grupo 2 começou a ingerir I. carnea no primeiro dia de desafio na pastagem e uma segunda reiniciou o consumo da planta no 182º dia. No final do experimento no 330º as cinco cabras avertidas com B. coridifolia permaneciam sem ingerir a planta. Estes resultados sugerem que B. coridifolia ou algum princípio ativo dessa planta pode ser utilizado para induzir aversão condicionada a plantas tóxicas. A utilização de B. coridifolia como agente aversivo é aparentemente mais barato e mais fácil de ser utilizado do que o LiCl, o qual requer o uso de sonda oro-gástrica e pessoal qualificado para sua implementação.

Triplex Doppler Ultrassonography in Prenatal of Pregnant Bitches

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Profile of IL-2, IL-4, IL-10, IFN- ? , TNF- ? and KC-like cytokines in pregnant bitches

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A multisensor, multitemporal approach for monitoring herbaceous vegetation growth in the Amazon floodplain

The Amazon River floodplain is an important source of atmospheric CO2 and CH4. Aquatic herbaceous vegetation (macrophytes) have been shown to contribute significantly to floodplain net primary productivity (NPP) and methane emission in the region. Their fast growth rates under both flooded and dry conditions make herbaceous vegetation the most variable element in the Amazon floodplain NPP budget, and the most susceptible to environmental changes. The present study combines multitemporal Radarsat-1 and MODIS images to monitor spatial and temporal changes in herbaceous vegetation cover in the Amazon floodplain. Radarsat-1 images were acquired from Dec/2003 to Oct/2005, and MODIS daily surface reflectance products were acquired for the two cloud-free dates closest to each Radarsat-1 acquisition. An object-based, hierarchical algorithm was developed using the temporal SAR information to discriminate Permanent Open Water (OW), Floodplain (FP) and Upland (UL) classes at Level 1, and then subdivide the FP class into Woody Vegetation (WV) and Possible Macrophytes (PM) at Level 2. At Level 3, optical and SAR information were combined to discriminate actual herbaceous cover at each date. The resulting maps had accuracies ranging from 80% to 90% for Level 1 and 2 classifications, and from 60% to 70% for Level 3 classifications, with kappa values ranging between 0.7 and 0.9 for Levels 1 and 2 and between 0.5 and 0.6 for Level 3. All study sites had noticeable variations in the extent of herbaceous cover throughout the hydrological year, with maximum areas up to four times larger than minimum areas. The proposed classification method was able to capture the spatial pattern of macrophyte growth and development in the studied area, and the multitemporal information was essential for both separating vegetation cover types and assessing monthly variation in herbaceous cover extent.

Continuous Electrical Current and Zinc Sulphate Administered by Transdermal Iontophoresis Improves Skin Healing in Diabetic Rats Induced by Alloxan: Morphological and Ultrastructural Analysis

Purpose. Evaluated the effects of continuous electrical current (CEC) or zinc administrated by transdermal iontophoresis (Zn+TDI). Methods. 120 male Wistar rats were submitted to an incision surgery at the anterior region of abdomen and distributed into 6 experimental groups with 40 animals: 3 diabetic groups and 3 normal groups, untreated and treated with CEC alone or with Zn+TDI. Each group was further divided into 4 subgroups with 10 rats each to be evaluated on the 4th, 7th, 14th, and 21st day after surgery. In each period, clinical and laboratory parameters from the animals were analyzed. Results. The analysis by optical and scanning electron microscopy showed a delay in the phases of wound healing in diabetic rats without treatment in all periods of the experiment; breaking strength (BS) was significantly reduced in skin scars of untreated diabetic rats when compared to other groups. In contrast, BS in skin scars of nondiabetic groups and diabetic rats treated with Zn+TDI showed significant increase in those, besides not presenting delayed healing. Conclusion. Electrical stimulation of surgical wounds used alone or in association with zinc by TDI is able to consistently improve the morphological and ultrastructural changes observed in the healing of diabetic animals.