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ABSTRACT Kaolinite is the main clay mineral in most soils around the world and has been widely used for industrial purposes. This research aimed to study chemical, morphological and crystallographic characteristics of kaolinite, and establish the origin of kaolinitic samples on Serra do Mar and kaolinitic layers on peatlands, located at Southern Brazil. Samples were collected on different geomorphological positions: two samples at Serra do Mar (kaolinitic saprolite – SAP, and kaolinitic layers - KL); and two cores at the peatland with Sapric Histosols from Quaternary sedimentary basin. Granulometry and total organic carbon (TOC) were determined in soil samples. Kaolinite in silt and clay fractions was studied by chemical extractions, X-ray diffraction (XRD), thermal analysis (DTA/TG), and scanning electron microscopy with energy dispersive spectroscopy – SEM/EDS. Chemical and mineralogical characteristics of kaolinite were divided into two groups, according to the particle size and the location of the deposit in the relief. Silt fraction: i) SAP – genesis mainly derived from mica weathering; ii) peatland, containing pseudomorph crystals smaller than those found in Serra do Mar; Clay fraction: i) Serra do Mar – there was a larger contribution of K-feldspar weathering in the genesis of kaolinite from KL in relation to SAP; ii) peatland – the stronger weathering and the hydromorphic conditions resulted in less neoformed crystalline kaolinites. For both environments, the substitution of Al3+ by Fe3+ into the octahedral sheet led to a reduction in the mineral thickness and also increased the occurrence of structural deformations in clay kaolinite. Kaolinite in peatland is a combination of the following genesis processes: transportation from Serra do Mar (mainly in the silt fraction) and; formation in situ through neogenesis process (dominant in the clay fraction).

ABSTRACT Most of the forensic comparison of soils has focused on the clay and silt fractions at the expense of the coarser particles. This study aimed to test the potential of elemental and physical analyses in the sand fraction from subtropical soils to discriminate samples collected in areas under different parent material (claystone and marble) and in areas with the same parent material at a simulated crime scene. Scanning electron microscopy coupled to an energy dispersive X-ray spectrometer (SEM-EDS) analysis was used on the finer sized sand particles (0.05-0.25 mm). X-ray diffraction (XRD) and particle size distribution (PSD) analyses were performed on the whole sand fraction. These methods did not provide clear discrimination of the sand of the soils sampled in the subtropical environment. This can be explained by the large homogenization observed in the sand fraction related to its chemical (EDS), physical (particle size distribution), morphological (SEM), and mineralogical (XRD). Under tropical and subtropical conditions, the chemical weathering processes dissolve most of the primary minerals, such as the feldspars, biotite, and Fe-bearing particles, and concentrates quartz in the sand fraction. In these environments, we recommend the prioritization of the finer soil fractions for forensic studies, both inorganic and organic.

RESUMO O Al trocável é tradicionalmente quantificado no extrato da solução de KCl 1 mol L-1; entretanto, nem sempre o Al provém unicamente de formas trocáveis desse elemento. Este trabalho objetivou investigar as formas de Al presentes em solos ácidos de várias regiões brasileiras, com distintas mineralogias, buscando elucidar se todo o Al-KCl corresponde às formas trocáveis do elemento. Foram testados os seguintes extratores para Al: Método tradicional (KCl 1 mol L-1), e variações desse método (curvas de titulação potenciométrica, método das extrações sucessivas e tamponado a pH 5), KCl 0,1 mol L-1, CaCl2 0,01 mol L-1, oxalato de amônio 0,2 mol L-1, pirofosfato de sódio 0,1 mol L-1 e CuCl2 0,5 mol L-1. A quantificação do elemento foi feita por titulação e, ou, por espectrofotometria de absorção atômica (EAA), quando pertinente. Foram analisadas amostras de dois horizontes (A e B) de perfis de solo de cinco estados brasileiros (AC, PE, BA, RS e SC). Dois perfis de solo de Santa Catarina, com níveis mais baixos de Al-KCl, foram utilizados como referência de solos mais intemperizados, com mineralogia caulinítica. Os resultados demonstraram que, particularmente nos solos ácidos com esmectitas, o KCl 1 mol L-1 extrai outras formas de Al além da trocável, superestimando seus valores, não sendo, portanto, um extrator indicado para a maioria dos solos analisados neste estudo. No entanto, a utilização dessa solução, porém mais diluída (KCl 0,1 mol L-1), teve menor efeito na dissolução desses compostos, podendo indicar de forma mais realista os teores de Al trocáveis do solo. As demais variações desse método (tampão pH 5, método potenciométrico e extrações sucessivas) não se evidenciaram adequadas para determinar esse elemento por extraírem quantidades similares ou até mais altas, quando comparadas com o método tradicional. Os altos teores de Al quantificados nos extratos de oxalato de amônio, cloreto de cobre e pirofosfato de sódio indicaram a participação expressiva de formas inorgânicas amorfas e de baixa cristalinidade, que contribuíram para a superestimação dos teores de Al nos solos estudados.

ABSTRACT: The purpose of this study was to describe our initial experience with double pelvic osteotomy (DPO) in young dogs affected by hip dysplasia (HD) and to report their postoperative outcome. Seven dogs (four females and three males) were included in our study with mean age 8.3 (±1.7) months, and mean body weight 29.5 (±7.4)Kg. Breeds involved were: Rottweiler (n = 1), Labrador Retriever (n = 3), Golden Retriever (n = 1), Great Dane (n=1) and São Miguel Cattle Dog (n = 1). The most common history complaints were: pelvic limb lameness and pain at hip extension and hip abduction. All surgical procedures consisted of osteotomy of the ilium and pubis, acetabular ventroversion and iliac stabilization with a customized bone plate with seven screws, four screws placed at the cranial fragment and the remaining three in the caudal aspect. Average surgical time was 65.8 (±10.4) minutes and median follow-up assessment was 68 (±15) days. Fracture healing was observed within mean period of 26.3 (±8.9) days. Six patients (86%) had satisfactory outcome and one patient didn’t improve after surgery and had to undergo a total hip replacement. Our results showed that DPO is an effective treatment for HD due to the preservation of pelvic geometry and low postoperative morbidity. Since it is a recent technique, further studies are recommended.

ABSTRACT Shrinkage capacity (caráter retrátil in Portuguese) is a new diagnostic characteristic recently introduced in the Brazilian System of Soil Classification (SiBCS) to indicate shrink and swell properties observed in subtropical soils from highland plateaus in southern Brazil, specifically in Oxisols with brown colors. In soils located in road cuts exposed to drying for some weeks, strong shrinkage of soil volume is observed in these soils, resulting in the formation of pronounced vertical cracks and large and very large prismatic structures, which crumble in blocks when handled. We hypothesize that such properties are related to their clay mineralogy, although there are no conclusive studies about this, the motive for the present study. Samples of the A and B horizons from six Oxisols with expansive capacity from the states of Santa Catarina and Rio Grande do Sul were analyzed. One Rhodic Hapludox, from the state of Paraná, without expansive capacity, was used for comparison. All the soils are very clayey, originated from basalt, and have similar iron oxide content. For identification of clay mineralogy, X-ray diffraction techniques were employed, together with the use of NEWMOD® software to investigate and describe the interstratified minerals. The results showed that most expansive soils have a similar mineralogical composition, with kaolinite, interstratified kaolinite-smectite (K-S), and hydroxy-Al interlayered smectites (HIS), unlike the non-expansive Rhodic Hapludox, which exhibited kaolinite with significant amounts of gibbsite and low amount of interstratified K-S. According to the mineralogical assemblage identified in the expansive soils, we can affirm that the mechanism of smectite expansion and contraction is related to the shrinkage capacity of the soil, considering that the level of hydroxy-Al intercalation is low. In addition, these mechanisms also are related to the presence of quasicrystals and domains that control the water dynamic in the smectites, contributing to shrinkage capacity.

A desnervação capsular (DC) se baseia na desperiostização da borda acetabular e tem sido utilizada como uma das técnicas de alívio da dor articular em cães displásicos. Compararam-se as técnicas de DC percutânea e aberta, aplicadas em 25 cães, que apresentaram diagnóstico clínico e radiográfico de displasia coxofemoral, totalizando 31 cirurgias. Os efeitos das técnicas foram comparados, em período de 180 dias, por meio de avaliação subjetiva de claudicação e dor, perimetria da coxa, graus máximos de flexão e extensão da articulação coxofemoral e amplitude de movimento articular. Os graus de claudicação e dor apresentaram decréscimo significativo ao longo do período avaliado em ambos os grupos, sem apresentarem diferenças quando comparados entre si. Com relação à perimetria da coxa, flexão, extensão e amplitude de movimento articular, foi observado o aumento dos valores numéricos destas variáveis ao longo do estudo. Baseado nos achados, concluiu-se que a abordagem percutânea ou aberta na DC produz similitude nas variáveis avaliadas, e ambas trazem bons resultados.Joint capsule denervation is based on removal of sensitive fibers from the acetabular edge and has been used as one of the techniques to joint pain relief in the canine dysplastic hip. This study compared the techniques of percutaneous and open hip denervation in 25 dogs that showed clinical and radiographic signs of hip dysplasia, totaling 31 surgeries. The effects of the techniques were evaluated and compared in a period of 180 days following surgery, including subjective evaluation of lameness and pain, thigh girth, maximum degree of hip flexion and extension and range of motion (ROM). Degree of lameness and pain significantly decreased during the study period for both groups, and no difference could be observed between groups. Thigh girth, degree of flexion, extension and ROM presented an increase in the numerical values throughout the study. Based on these findings, it is concluded that the percutaneous or open approach for capsular denervation produced similar results.

Determinaram-se os índices de largura da fossa intercondilar (FI), após transecção do ligamento cruzado cranial em nove cães adultos submetidos à estabilização articular com retalho de fáscia lata. Os joelhos foram alocados em dois grupos, sendo o joelho direito (GI) submetido à incisuroplastia troclear (ITR) e posterior estabilização articular, e o joelho esquerdo submetido somente à substituição ligamentar (GC). Cada grupo foi dividido em três subgrupos correspondentes aos momentos de eutanásia aos 30, 90 e 180 dias de pós-operatório. Os índices de largura da FI foram determinados, macroscópica e radiograficamente, pela mensuração da abertura cranial da FI nos terços cranial, médio e caudal, e indexados em relação à largura epicondilar. Observou-se aumento significativo dos índices macroscópicos e radiográficos nas articulações do GI, sendo estes estatisticamente diferentes daqueles das articulações de GC. Não foi observada estenose intercondilar nos joelhos de GC após a estabilização articular. Conclui-se que a estabilização articular com retalho de fáscia lata preveniu a estenose da fossa intercondilar, e que a ITR promoveu o alargamento permanente dessa estrutura.Intercondylar fossa width indexes (IFWI) were determined in nine adult dogs submitted to intercondylar notchplasty (IN) after transection of the cranial cruciate ligament (CCL) followed by a fascial strip stabilization. The right stifle was submitted to IN followed by fascial strip reconstruction of the CCL (GI) while in the left stifle IN was not performed (GC). Each group was then divided into three subgroups which corresponded to time of euthanasia at 30, 90 and 180 days after surgery. IFWI were determined, both macroscopically and radiographically, by measuring the cranial outlet of the intercondylar fossa in relation to the epicondylar width. A significant increase was observed in indexes of GI following IN, and these differed from indexes of GC throughout the evaluation period. It was concluded that articular repair using a fascia strip prevented stenosis of the intercondylar fossa, and that IN caused a permanent widening of it.

In this study the authors aimed to compare the efficiency of carprofen, ketoprofen and vedaprofen for alleviating postoperative pain in bitches submitted to ovariohysterectomy (OH). Pre- and postoperative assessment of pain was made using serum levels of cortisol and glucose, the visual analogue scale (VAS) and the University of Melbourne pain scale (UMPS) in twenty-one bitches undergoing OH. Dogs were randomly assigned to one of three groups: vedaprofen at 0.5mg kg-1, carprofen at 2.2mg kg-1 or ketoprofen at 2.2mg kg-1. All analgesics were given orally 2 hour before surgery. Assessments were made before surgery and at 1, 2, 3, 4, 5, 6, 7, 8, 12 and 24 hours post-extubation. No dog of this study required additional doses of analgesics. There were no significant differences on serum cortisol and glucose concentrations among groups or from basal values, excepted one hour after extubation. No significant differences on pain scores were observed. It was concluded that vedaprofen provided as good a level of postoperative analgesia as carprofen and ketoprofen.O objetivo deste estudo foi comparar a eficiência do carprofeno, do cetoprofeno e do vedaprofeno no alívio da dor pós-operatória em cadelas submetidas à ovariohisterectomia (OH) eletiva. Para tal, foram realizadas avaliações pré e pós-operatórias de cortisol e glicose séricos e foram usadas a escala análoga visual (VAS) e a escala da Universidade de Melbourne (University of Melbourne Pain Scale - UMPS). Vinte e uma cadelas foram distribuídas aleatoriamente em três grupos de sete animais cada: vedaprofeno 0,5mg kg-1, carprofeno 2,2mg kg-1 ou cetoprofeno 2,2mg kg-1. Todos os analgésicos foram administrados pela via oral, duas horas antes da cirurgia. As avaliações foram realizadas antes da cirurgia e uma, duas, três, quatro, cinco, seis, sete, oito, 12 e 24 horas após a extubação. Nenhum dos cães precisou de analgesia de resgate. Com exceção dos valores observados uma hora após a extubação, não houve diferenças significativas nas concentrações séricas de cortisol e glicose entre grupos ou quando foram comparadas aos valores basais. Tampouco houve diferenças significativas nos escores de dor entre as escalas usadas, nos tempos de avaliação para cada grupo, nem entre os grupos. Concluiu-se que o vedaprofeno fornece analgesia pós-operatória de qualidade similar à obtida com carprofeno e com cetoprofeno.

The present study aimed to evaluate a modification of the stabilization method of the tibial tuberosity advancement technique (TTA), originally described for stabilization of the cranial cruciate deficient stifle. Ten adult mongrel dogs with weights ranging from 25 to 30kg were used. After euthanasia, the hind-limbs were divided into two groups: G1 - test (n=10), and G2 - control (n=10) represented by the contra lateral limb. The test group was submitted to the modified TTA technique, stabilized by one shaft screw in craniocaudal position and a titanium cage inserted at the osteotomy site. The position of the patellar tendon, 90° in relation to the tibial plateau, and the correct position of all implants were confirmed radiographically after surgery. Posteriorly, in both groups, limbs were harvested and tibias collected with their respectively patellar tendon insertion preserved for the mechanical resistance test. The fixation of the tibial tuberosity with a shaft screw and titanium cage resulted in resistance compatible with the normal physiological forces transferred to the hind-limbs during locomotion. The biomechanical tests confirmed the viability of the method performed for the tibial tuberosity fixation and support future clinical trials to validate the technique.O presente estudo teve por objetivo avaliar a resistência mecânica do método de estabilização da técnica de avanço da tuberosidade tibial (TTA), originalmente descrita para tratamento da ruptura do ligamento cruzado cranial. Foram avaliados 10 cães, sem raça definida e com massa corporal entre 25 e 30kg. Após a eutanásia, os membros pélvicos foram divididos em dois grupos, sendo que G1 era o grupo teste (n=10) e G2 o controle (n=10), representado pelo membro contralateral. O grupo operado foi submetido à técnica de avanço da tuberosidade tibial (TTA) modificada, com emprego de um parafuso especial em posição craniocaudal e um espaçador de titânio inserido no local de osteotomia. O posicionamento do tendão patelar perpendicularmente ao platô tibial e o correto posicionamento dos implantes foi confirmado radiograficamente em todos os espécimes. Posteriormente, em ambos os grupos foram coletadas as tíbias, com preservação da inserção dos seus respectivos tendões patelares, para realização dos testes de resistência mecânica. A estabilização da tuberosidade tibial por parafuso especial em sentido craniocaudal e espaçador de titânio demonstrou resistência compatível com as forças fisiológicas tradicionalmente impostas ao membro pélvico durante a locomoção. Os testes biomecânicos confirmam a viabilidade do método de estabilização e sustentam estudos clínicos futuros para validação da técnica cirúrgica.

The present study aimed to determine biomechanical alterations resultant from a modification in the fixation method of the tibial tuberosity advancement technique (TTA), originally described for stabilization of the cranial cruciate-deficient stifle. Ten adult mongrel dogs weighing 25-30kg were used. After euthanasia, performed for reasons unrelated to this study, the hind limbs were distributed into two groups: G1 operated (n=10) and G2 control (n=10), represented by the contralateral limb. The operated hind limbs were orthopedically, goniometrically and radiographically evaluated, sequentially at four moments: moment 1, in intact joints; moment 2, after cranial cruciate desmotomy; moment 3, after surgical stabilization of the stifle joint using modified TTA; and moment 4, after caudal cruciate ligament desmotomy. The tibial tuberosity was stabilized by one shaft screw craniocaudally and a titanium cage inserted at the osteotomy site. The position of the patellar tendon at 90° in relation to the tibial plateau allowed cranial tibial thrust force neutralization, despite cranial drawer motion maintenance in all dogs. The biomechanical tests confirm the viability of the tibial tuberosity fixation method and support future clinical trials to validate the technique.O presente estudo teve como objetivo determinar as alterações biomecânicas decorrentes da modificação da técnica de avanço da tuberosidade tibial (TTA), originalmente descrita para estabilização da ruptura do ligamento cruzado cranial. Foram avaliados 10 cães, sem raça definida e com peso entre 25 e 30kg, submetidos à eutanásia por razões independentes do presente estudo. Os membros pélvicos foram distribuídos em dois grupos: G1 operado (n=10) e G2 controle (n=10), representado pelo membro contralateral. Os membros operados foram submetidos à avaliação ortopédica, goniométrica e radiográfica nos momentos 1 (articulação intacta), 2 (após desmotomia do cruzado cranial), 3 (após estabilização articular pela TTA modificada) e 4 (após a desmotomia do cruzado caudal). A tuberosidade tibial foi estabilizada por um parafuso cortical em posicionamento craniocaudal e um espaçador de titânio inserido no local de osteotomia. A posição do tendão patelar perpendicular em relação ao platô tibial promoveu a neutralização da força de cisalhamento tibial cranial, apesar da permanência do movimento de gaveta cranial em todos os joelhos. Os testes biomecânicos confirmam a viabilidade do método empregado para estabilização da tuberosidade tibial e sustentam a realização de estudos clínicos futuros para validação da técnica.

A displasia coxofemoral canina (DCF) é uma afecção ortopédica freqüente, comumente dolorosa, decorrente de instabilidade e que leva à doença articular degenerativa. Várias formas de tratamento cirúrgico são descritas, entre elas a denervação capsular a céu aberto. Neste trabalho, é descrita a denervação capsular percutânea e seus efeitos em 92 cães com sensibilidade dolorosa na articulação do quadril atribuída à DCF. Foram avaliados os seguintes aspectos: o grau de claudicação (CLAUD), a dor por escala analógica visual, a perimetria da coxa (PC) e os graus máximos de extensão (GME) e flexão (GMF) passiva do quadril imediatamente antes da cirurgia e aos sete, 15, 30, 180 e 360 dias de pós-operatório (p.o.). Os animais foram pré-medicados e submetidos à anestesia geral inalatória e, posteriormente, a borda acetabular crânio-dorsal foi denervada por meio da introdução percutânea de um pino de Steinman com aproximadamente 4,5mm de diâmetro. A CLAUD e a dor foram analisadas por meio da ANOVA e do teste de Friedman. A PC, a GME e a GMF foram analisadas por meio da ANOVA e do teste de Tukey. Foi observada melhora significativa na CLAUD e dor a partir dos 15 dias de p.o. A GME apresentou aumento significativo já aos 30 dias de p.o., enquanto que a PC apresentou aumento significativo após os 60 dias de p.o. Conclui-se que a denervação capsular percutânea é alternativa cirúrgica eficaz em restabelecer a movimentação do quadril displásico e promove melhora significativa da dor e claudicação.Canine hip dysplasia is a common painfull orthopedic disorder, resulting from articular instability and causing degenerative joint disease. Several treatment options are available, including capsular denervation. This study describes the results of percutaneous capsular denervation in 92 dogs diagnosed with hip dysplasia. Lameness (LAM) and pain on palpation (PN) were determined using a visual analogue scale (VAS), muscle girth (MG) and maximum degree of passive extension (PME) and flexion (PMF) of the hip were determined pre-operatively and at days 7, 15, 30, 180 and 360 post-operatively. Dogs were anesthetized and 4.5mm Steinman pin was used to percutaneously scrap the craniodorsal border of the acetabulum. LAM and PN were analyzed by means of ANOVA followed by a Friedman test, whereas MG, PME and PMF were analyzed by means of ANOVA followed by a Tukey test. There was a significant decrease in LAM and PN 15 days following surgery. PME presented a significant increase after 30 days of surgery. It is concluded that the percutaneous hip denervation is an effective method in restoring function in the dysplastic hip.

Avaliaram-se as alterações clínicas e radiográficas em nove cães adultos, após a transecção do ligamento cruzado cranial (LCCr) seguida da substituição ligamentar por retalho de fáscia lata, associada ou não à incisuroplastia troclear (ITR). O joelho direito (GI) foi submetido à ITR e posterior estabilização articular, e o esquerdo somente à substituição ligamentar (GC). Os animais foram avaliados nos períodos pré-operatório, pós-operatório (po) imediato e aos 30, 90 e 180 dias de po, período coincidente com o momento de eutanásia de subgrupos de três cães. A instabilidade articular e o grau de claudicação diminuíram significativamente durante o período de avaliação, apesar da instabilidade persistir durante a flexão articular. Observou-se decréscimo significativo do perímetro muscular da coxa aos 30 e 90 dias p.o. em ambos os grupos. Não foram evidenciadas alterações nos graus de extensão e flexão articulares, na rotação interna da tíbia, na amplitude de movimento articular ou de doença articular degenerativa (DAD) durante o período de avaliação em ambos os grupos. Conclui-se que a ITR, associada à técnica de estabilização articular, não produz alterações em nenhuma das variáveis estudadas em cães, quando comparada à estabilização intra-articular, isoladamente.Clinical and radiographic changes associated with intercondylar notchplasty (IN) after transection of the cranial cruciate ligament (CCL) followed by a fascial strip reconstruction were studied in nine adult dogs. The right stifle was submitted to IN followed by fascial strip reconstruction of the CCL (GI) while in the left IN was not performed (GC). Dogs were evaluated the day prior to surgery, on the immediate postoperative day and at 30, 90 and 180 days after surgery, time at which a subgroup of three dogs were euthanatized. Instability and lameness significantly decreased throughout the evaluation period, although instability was observed during flexion. There was a significant decrease in muscle perimeter at 30 and 90 days po in both groups. Changes in degree of extension, flexion, internal rotation of the tibia, range of motion, or DAD were not observed throughout the evaluation period in any group. It is concluded that IN, followed by a fascial strip reconstruction of the CCL does not cause any change in the variables studied in dogs, when compared to a fascial strip reconstruction alone.

Avaliou-se o centro instantâneo de movimento e vetor velocidade após a transecção do ligamento cruzado cranial (LCCr), seguida da substituição ligamentar por retalho de fáscia lata, associada ou não a incisuroplastia troclear (ITR) em nove cães adultos. O joelho direito (GI) foi submetido a ITR e posterior estabilização articular, e o joelho esquerdo submetido somente a substituição ligamentar (GC). Os animais foram avaliados nos períodos pré-operatório, pós-operatório imediato e aos 30, 90 e 180 de pós-operatório, correspondente ao momento de eutanásia de subgrupos de três animais. O centro instantâneo de movimento (CIM) e o vetor velocidade (Vv) resultante foram determinados por meio do deslocamento de pontos a partir da análise radiográfica dos joelhos. Todas as articulações apresentavam CIM e Vv normais antes da transecção do ligamento cruzado cranial. Após a estabilização articular, acompanhada ou não de ITR, observou-se o posicionamento normal do CIM e Vv resultante, em todos os períodos de avaliação, apesar da presença de movimento de gaveta em três animais de GC e dois de GI no pós-operatório imediato, em dois animais de cada grupo, aos 30 dias de avaliação, e em um animal em cada grupo nas avaliações subseqüentes. Conclui-se que a estabilização articular com retalho de fáscia lata, associada ou não a ITR, mantém a integridade biomecânica do joelho, quando considerados o CIM e o Vv.The instantaneous center of motion (ICM) and velocity vector (Vv), after transection of the cranial cruciate ligament (CCL) followed by a fascial strip reconstruction in association with intercondylar notchplasty (IN), were studied in nine adult dogs. The right stifle was submitted to IN followed by fascial strip reconstruction of the CCL (GI) while in the left stifle IN was not performed (GC). Dogs were evaluated the day prior to surgery, immediately after surgery and at 30, 90 and 180 days postoperatively (po), time at which a subgroup of three dogs were euthanatized. The ICM and resulting Vv were determined by radiographic examination of the stifle. All the stifles presented normally positioned ICM and Vv before surgery. No changes were observed in ICM or Vv in all stifles following intra-articular repair, in association or not with IN, throughout the evaluation period, despite the fact that three dogs in GC and two in GI presented a positive cranial drawer sign immediately following surgery, two dogs in GC and GI at 30 days po, and one single dog in each group thereafter until 180 days po. It is concluded that articular repair, in association with IN or not, did not alter stifle biomechanics, in respect to ICM and Vv.

Este estudo comparou o efeito na biomecânica articular de dois fios de sutura, aço e polipropileno, na estabilização do joelho após transecção do ligamento cruzado cranial de cães, utilizando-se a técnica extra-articular de sutura fabelo-tibial. O centro instantâneo de movimento e o vetor velocidade resultante, foram calculados por meio de análise radiográfica das articulações fêmur-tíbio-patelares de doze cães, antes e após a desestabilização e estabilização articular. Todas as articulações apresentavam centro instantâneo e vetor velocidade normais antes da transecção do ligamento. Após a mesma, observou-se o posicionamento anormal do vetor velocidade em onze articulações. Na análise radiográfica posterior à estabilização articular, quatro articulações do grupo nos quais foi empregado o fio de aço continuaram apresentando posicionamento anormal do vetor velocidade, enquanto todas as articulações do grupo em que foi utilizado o fio de polipropileno apresentaram vetor velocidade em posição tangente às superfícies ósseas. Conclui-se que o fio de polipropileno é mais indicado na estabilização extra-articular por manter a biomecânica articular inalterada.This study evaluated the effect of two suture materials, stainless steel wire and polypropylene, on the stifle joint biomechanics by means of analysis of the instantaneous center of motion after stabilization of cranial cruciate ligament-deficient stifle with the fabelo-tibial suture technique. The instantaneous center of motion and resulting velocity vectors were determined by radiographic examination of the stifle joint in twelve dogs before and after cranial cruciate ligament transection, and after joint stabilization. All the stifles showed normally positioned instantaneous centers of motion and velocity vectors before cranial cruciate ligament transection. Eleven joints had abnormally positioned velocity vectors after transection of the cranial cruciate ligament. After joint stabilization, four joints in the stainless steel wire suture group continued showing abnormal velocity vectors, while all stifles joints in the polypropylene group had normal positioned velocity vectors. The polypropylene suture is more adequate for extra-articular stabilization as it maintains the normal joint biomechanics.

The present study aimed to determine biomechanical alterations resultant from a modification in the fixation method of the tibial tuberosity advancement technique (TTA), originally described for stabilization of the cranial cruciate-deficient stifle. Ten adult mongrel dogs weighing 25-30kg were used. After euthanasia, performed for reasons unrelated to this study, the hind limbs were distributed into two groups: G1 operated (n=10) and G2 control (n=10), represented by the contralateral limb. The operated hind limbs were orthopedically, goniometrically and radiographically evaluated, sequentially at four moments: moment 1, in intact joints; moment 2, after cranial cruciate desmotomy; moment 3, after surgical stabilization of the stifle joint using modified TTA; and moment 4, after caudal cruciate ligament desmotomy. The tibial tuberosity was stabilized by one shaft screw craniocaudally and a titanium cage inserted at the osteotomy site. The position of the patellar tendon at 90° in relation to the tibial plateau allowed cranial tibial thrust force neutralization, despite cranial drawer motion maintenance in all dogs. The biomechanical tests confirm the viability of the tibial tuberosity fixation method and support future clinical trials to validate the technique.

ABSTRACT Many Amazonian farmers use the slash-and-burn method rather than fertilization for crop production. The aim of the present study was to evaluate changes in the morphological, physical, and chemical properties of naturally fertile Inceptisols after conversion from native forest to different uses in southern Amazonia, Brazil. Land covered by dense native forest (NF) was split into four areas of 1.0 ha each. Three areas were slashed and burned and then cultivated for 11 years with coffee (CO), secondary forest (SF), and pasture (PA). Four soil profiles were sampled in each treatment (four uses × four replicates). The mean value distribution of each physical and chemical analysis was determined for different depths, and standard error bars were placed to display significant differences among treatments. Results showed that morphology and physical properties were negatively affected after the establishment of PA and CO: a reduction in the thickness of the A horizon and in aggregate stability, a decrease in total porosity and macroporosity, and an increase in aggregate size and bulk density. Soil bulk density (SBD), geometric mean diameter of water-stable aggregates (GMD), and microporosity (SMi) were higher in soil under pasture as a consequence of more intense soil surface compaction. Native and secondary forests were the only treatments that showed granular structures in the A horizon. Significant differences between native forest and secondary forest were mainly found in the top soil layer for total porosity (STP) (NF>SF), macroporosity (SMa) (NF>SF), SBD (NF>SF) and GMD (SF>NF). Phosphorus contents in the A horizon increased from 6.2 to 21.5 mg kg-1 in PA and to 27.2 mg kg-1 in SF. Soil under coffee cultivation exhibited the lowest levels of Ca2+ and sum of bases in surface horizons. In all slash-and-burn areas there was a reduction in the C stock (Mg ha-1) of the A horizon: native forest 6.3, secondary forest 4.5, pasture 3.3, and coffee 3.1.

ABSTRACT Soil traces are useful as forensic evidence due to their potential to transfer and adhere to different types of surfaces on a range of objects or persons. Several works have been developed in forensic soils, under different analytical approaches. However, in Brazil, only the researches from the Group of the Federal University of Paraná have developed works with soils under a forensic approach. Focus has been given on the sequential chemical analyses and mineralogical techniques once they presented a large potential to discriminate soil samples, even that originated from the same bedrock. In this way, this work aimed to test a Standard Operating Procedure (SOP) for forensic soil sampling and an analytical protocol in Brazil between the academy and the scientific police through a blind simulated crime scene scenario. Samples were collected at four sites located in the Curitiba Metropolitan Region. All soils were classified as Inceptisol ( Cambissolo ), and the parent material in Curitiba is claystone and in Colombo is limestone. Around 3 g of sample composed by silt + clay fraction were isolated and analyzed by sequential chemical procedure: i) extraction of poorly ordered iron and aluminum oxides with ammonium oxalate (AO); ii) extraction of crystalline iron oxides with sodium dithionite-citrate-bicarbonate (DCB); and iii) extraction of poorly ordered aluminosilicates and gibbsite with NaOH 0.5 mol L-1. All data were transformed by square root and formed a data matrix subsequently analyzed in a principal component analysis (PCA). Most of the samples were properly grouped according to their provenance at all four sites tested, showing the potential of the Standard Operating Procedure (SOP) in a real crime scene. The sampling procedures presented in the SOP were detailed enough to allow the appropriate police work in forensic cases in any part of Brazil. As future considerations, modifications to the sample treatment and analytical protocol could be made depending on the context of the forensic work. Intense anthropogenic activities, such as domestic waste disposal in urban areas, would potentially reduce the discrimination power of such a proposed chemical analytical protocol.