Análise de processos alternativos na preparação de esqueletos para uso didático

Zoology laboratories at institutions of research and education have shown great demand for anatomical parts for practical lessons. However, although the bibliography is not necessarily scarce, analyses of the cost/benefit relations of such processes are rare, considering aspects such as preparation time, quality of the anatomical parts, and material and human resources. In addition to the common techniques already used, new low-cost products, not cited in literature and easily found in the market, were also tested. The main objective of this work was to elaborate and organize information on techniques of bone parts maceration for study collections, making comparative analyses on the cost/benefit relations of each technique. Twelve products were tested, evaluating experimental conditions such as: concentration and combination of reagents, temperature, pH and time of exposure of the parts to the reagents. The results indicated that the products recommended for the use in the maceration processes were: water, hydrogen peroxide and papaya juice (Carica papaya).

Reactores aeróbios de lecho fluidizado trifásico con circulación interna: Caracterización hidrodinámica y del soporte

Aerobic internal-loop reactors use active biomass attached in a supporting media (biofilm) with the advantage of retaining a big biomass concentration in a small physical space, removing carbonaceous matter and nitrogen in only one reactor. Liquid circulation occurs due to hydrostatic pressure difference produced by air injection in the riser. In biphasic conditions liquid circulation velocities, gas holdup and oxygen transfer coefficient in four different reactor configurations were studied. For the three-phase conditions, the same parameters in just one of those configurations were evaluated. Also, there were three granular supporting media characterized. On the other hand, the relationship between internal and external tube areas and supporting media concentrations influence the liquid velocity, gas holdup and oxygen mass transfer values and some important supporting media characteristics were observed and compared.

Thermal behaviour of succinic acid, sodium succinate and its compounds with some bivalent transitions metal ions in dynamic N 2 and CO 2 atmospheres

Thermal stability and thermal decomposition of succinic acid, sodium succinate and its compounds with Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) were investigated employing simultaneous thermogravimetry and differential thermal analysis (TG-DTA) in nitrogen and carbon dioxide atmospheres and TG-FTIR in nitrogen atmosphere. On heating, in both atmospheres the succinic acid melt and evaporate, while for the sodium succinate the thermal decomposition occurs with the formation of sodium carbonate. For the transition metal succinates the final residue up to 1180 °C in N 2 atmosphere was a mixture of metal and metal oxide in no simple stoichiometric relation, except for Zn compound, where the residue was a small quantity of carbonaceous residue. For the CO 2 atmosphere the final residue up to 980 °C was: MnO, Fe 3O 4, CoO, ZnO and mixtures of Ni, NiO and Cu, Cu 2O.

Osteossarcoma mandibular em gato: Relato de Caso

The primary malignant bone tumors are uncommon in cats. Osteosarcoma is the most frequently observed in old animals. This tumors affects the appendicular skeleton, however the axial skeleton is also affected, but the bones of the head and pelvis frequent sites of injury. This paper reports a case of a cat with a history of progressive swelling in the left mandible, with follow-up period of four months. The presumptive diagnosis of osteopathy, signed by clinical and radiographic observations were confirmed by histopathology and there it is moderately productive osteoblastic osteosarcoma.

Dental age as indicator of adolescence

Aim: The purpose of the present study was to analyze the relationship between root formation of the first premolars and skeletal maturation stages identified in hand-wrist radiographs. Methods: A cross-sectional study was carried out involving the panoramic and hand-wrist radiographs obtained on the same date of 232 patients, 123 boys and 109 girls aged 4 years and 5 months to 17 years and 12 months. Root formation stages of the first premolars were related to the ossification stages of the sesamoid bone, epiphyseal stages of the phalanx of the thumb and epiphyseal stages of the radius. Results: The studied variables demonstrated statistically significant correlations. Conclusion: Roots of the lower first premolars do not reach 2/3 of their complete length before adolescence.

Viscosity, pH, and moisture effect in the porosity of poly(furfuryl alcohol)

The poly(furfuryl alcohol) is highly indicated to obtain advanced carbonaceous materials due mainly to its good carbon yield (around 50%) and a controllable cure reaction. In the processing of some carbonaceous materials, such as monolithic vitreous carbon, it is necessary to make sure that the material has the smallest porosity to be used in nobler applications such as heart valves and aerospace integrated systems. In this manuscript, a design of experiments was used to study the influence of viscosity, pH, and moisture in the porosity of the cured material. This study shows that the moisture exerts a significant influence on the porosity and the trend of the results lead to conclude that lower viscosity and moisture, and the use of non-neutralized poly(furfuryl alcohol) resins lead to obtain materials with better quality. © 2012 Wiley Periodicals, Inc.

Comparative analysis between three methods of bone estimating age in individuals with down syndrome by mode of the hand and wrist ray

The wrist and hand region has been the most commonly used for estimating age and osseous development due to the great number of ossification centers. The aim was to determine which method, Tanner & Whitehouse's (TW3), Greulich & Pyle's (GP) or Eklof & Ringertz's, more closely relates to the chronological age in subjects with Down syndrome with chronological ages between 61 and 180 months, using wrist and hand radiographs. The sample consisted of 85 radiographs, 52 of males and 33 of females. Eklof & Ringertz's method was computerized (Radiomemory). Greulich & Pyle's atlas was used and compared with the wrist and hand radiographs. For the TW3 method, 13 ossification centers were evaluated; for each one of them, there are seven or eight development stages to which scores are assigned; these scores are then added and the results are transformed into osseous age values. No statistically significant differences were observed between the male and female genders for methods TW3 and GP, contrasting with the observed differences for the Eklof & Ringertz method. Correlation (r2) between osseous and chronological ages was 0.8262 for TW3 and 0.7965 for GP, while for the method of Eklof & Ringertz, it was 0.7656 for females and 0.8353 for males. The author concluded that the osseous age assessment method that better related to the chronological age was the TW3, followed by Greulich & Pyle's and Eklof & Ringertz's.

A comparative study of glycerol dehydration catalyzed by micro/mesoporous MFI zeolites

The catalytic properties of monomodal microporous and bimodal micro-mesoporous zeolites were investigated in the gas-phase dehydration of glycerol. The desilication methodology used to produce the mesoporous zeolites minimized diffusion limitations and increased glycerol conversion in the catalytic reaction due to the hierarchical system of secondary pores created in the zeolite crystals. The chemical and structural properties of the catalyst were studied by X-ray diffraction, nitrogen adsorption-desorption isotherms, NH3-TPD and pyridine chemisorption followed by IR-spectroscopy. Although the aim was to desilicate to create mesoporosity in the zeolite crystals, the desilication promoted the formation of extra-framework aluminum species that affected the conversion of glycerol and the products distribution. The results clearly show that the mesoporous zeolites with designed mesopore structure allowed a rapid diffusion and consequently improved the reaction kinetics. However, especial attention must be given to the desilication procedure because the severity of the treatment negatively interfered on the Brønsted and Lewis acid sites relative concentration and, consequently, in the efficiency of the catalysis performed by these materials. On the other hand, during the catalytic reaction, the intracrystalline mesopores allowed carbonaceous compounds to be deposited herein, resulting in less blocked micropores and catalysts with higher long-term stability.

Bone morphology of the hind limbs in two caviomorph rodents

In order to evaluate the hind limbs of caviomorph rodents a descriptive analysis of the Cuniculus paca (Linnaeus, 1766) and Hydrochoerus hydrochaeris (Linnaeus, 1766) was performed using anatomical specimens, radiography, computed tomography (CT) and full-coloured prototype models to generate bone anatomy data. The appendicular skeleton of the two largest rodents of Neotropical America was compared with the previously reported anatomical features of Rattus norvegicus (Berkenhout, 1769) and domestic Cavia porcellus (Linnaeus, 1758). The structures were analyzed macroscopically and particular findings of each species reported. Features including the presence of articular fibular projection and lunulae were observed in the stifle joint of all rodents. Imaging aided in anatomical description and, specifically in the identification of bone structures in Cuniculus paca and Hydrochoerus hydrochaeris. The imaging findings were correlated with the anatomical structures observed. The data may be used in future studies comparing these animals to other rodents and mammalian species. © 2012 Blackwell Verlag GmbH.

Origin and impact of the oldest metazoan bioclastic sediments

The emergence of soft-bodied metazoans and the radiation of the earliest skeletal organisms substantially changed the ecological dynamics of Ediacaran environments, leading to the genesis of biogenic hard-part deposits for the fi rst time in Earth's history. The impact of bioclast origin on sedimentary processes is analyzed herein, focusing on the sedimentology and taphonomy of shell concentrations dominated by the Ediacaran index fossil Cloudina from the Itapucumí Group, Paraguay. Skeletal concentrations include both dense accumulations of parautochthonous, disarticulated specimens (Type 1 deposits) and in situ specimens preserved as loosely packed assemblages (Type 2 deposits). At that time, Cloudina was the critical source of durable biomineralized hard parts in an environment nearly free of other bioclasts. The simple fabric and geometry of these accumulations are typical of Cambrian-style shell beds. Despite their Precambrian age, these deposits indicate that the establishment of the Phanerozoic style of marine substrates and preservation in early shell beds was determined more by the acquisition of hard parts than by environmental changes. © 2013 Geological Society of America.

Conservative condylectomy for management of osteochondroma of the mandibular condyle

Osteochondroma is one of the most common benign tumors of the skeleton. This tumor is rare in the craniofacial region, with the most common sites of occurrence being the coronoid process of the mandible and the mandibular condyle. Traditionally, the treatments of these lesions include total condylectomy or local resection of the lesion. Conservative condylectomy procedure with reshaping of the remaining condylar neck and repositioning of the articular disk has been suggested. This article aimed to describe a 35-year-old woman with osteochondroma in the left mandibular condyle who was treated by conservative condylectomy. The patient has been free of recurrence for 2 years, showing good aesthetic and functional stability. Copyright © 2013 by Mutaz B. Habal, MD.

Management of pure medial orbital wall fracture with autogenous bone graft

The orbit is an irregular conical cavity formed from 7 bones including the frontal, sphenoid, zygomatic, maxillary, ethmoid, lacrimal, and palatine bones. Fractures of the internal orbit can cause a number of problems, including diplopia, ocular muscle entrapment, and enophthalmos. Although muscle entrapment is relatively rare, diplopia and enophthalmos are relatively common sequelae of internal orbital fractures. Medial orbital wall fracture is relatively uncommon and represents a challenge for its anatomical reconstruction. In this context, autogenous bone graft has been the criterion standard to provide framework for facial skeleton and orbital walls. Therefore, it is possible to harvest grafts of varying size and contour, and the operation is performed through the bicoronal incision, which is the usual approach to major orbital reconstruction. Thus, this article aimed to describe a patient with a pure medial orbital wall fracture, and it was causing diplopia and enophthalmos. The orbital fracture was treated using autogenous bone graft from calvarial bone. The authors show a follow-up of 12 months, with facial symmetry and without diplopia and enophthalmos. In addition, a computed tomography scan shows excellent bone healing at the anterior and posterior parts of the medial orbital wall reconstruction. Copyright © 2013 by Mutaz B. Habal, MD.

Transformação do glicerol em compostos de interesse petroquímico catalisada por zeólitas com ordem hierárquica de poros

Pós-graduação em Química - IQ

Prática de atividade física e qualidade de vida de pacientes com osteoporose e osteopenia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da densidade mineral óssea e os fatores a ela associados em indivíduos adultos com Diabetes Mellitus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)