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Feline oral squamous cell carcinoma (FOSCC) is an aggressive cancer in domestic cats that has no effective treatment option when advanced. Preventative or early diagnostic measures are thus crucial. FOSCC is also a model for human head and neck SCC (HNSCC); strong risk factors in HNSCC include exposure to alcohol, tobacco, areca nut, and high‐risk human papillomavirus. Previous studies have identified flea collar and tobacco smoke exposure, feeding canned tuna, canned cat food and cat foods with chemical additives, living in a rural environment, and having outdoor access as risk factors for FOSCC but there was no overlap in the risk factors between studies. In our study, risks for FOSCC were evaluated in an online epidemiologic survey study in 67 cats with FOSCC and 129 control cats. Clumping clay cat litter and flea collar use were significant risk factors for FOSCC on multiple logistic regression with odds ratios of 1.66 (95% CI 1.20–2.30) and 4.48 (95% CI 1.46–13.75) respectively. Crystalline silica is a carcinogen that may be present in all clay cat litters and tetrachlorvinphos is a carcinogen that is present in the most commonly used flea collars in our study. We recommend further investigation into the association between FOSCC and clay‐based litter and/or flea collars containing tetrachlorvinphos. [ABSTRACT FROM AUTHOR]

A 10‐year‐old male castrated Labrador Retriever cross was referred for evaluation of acute vision loss. Ophthalmic examination revealed mild left sided exophthalmos, bilateral resting mydriasis, an absent direct and reduced consensual PLR in the left eye and reduced direct and absent consensual PLR in the right eye. Examination of the cornea and anterior segment with slit lamp biomicroscopy was unremarkable. Indirect fundoscopy revealed a left optic nerve head obscured by a darkly pigmented lesion. Fundic examination in the right eye was unremarkable. Magnetic resonance imaging revealed a smoothly marginated, lobulated cone to irregularly shaped, strongly T1 hyperintense, T2 and T2 fluid‐attenuated inversion recovery hypointense, strongly contrast enhancing mass closely associated with the entire left optic nerve, extending across the optic chiasm and into the right optic nerve ventrally. Full clinical staging revealed no evidence of metastasis. Exenteration of the left eye was performed. Histopathology revealed an unencapsulated, poorly demarcated, multilobulated and infiltrative pigmented mass that was effacing the posterior choroid and optic nerve. The mass was composed of a moderately pleomorphic population of heavily pigmented polygonal cells arranged in sheets and clusters, displaying moderate anisocytosis and anisokaryosis. The population of cells contained moderate amounts of abundant brown‐black granular pigment consistent with melanin within the cytoplasm. Mitotic figures averaged approximately three per ten 400× fields (2.37 mm2). This is the first report of a melanocytic tumor invading along the optic nerve and tract to result in contralateral vision loss. [ABSTRACT FROM AUTHOR]

Shrinkage and relaxation motions of flexible FePd nanohelices of FePd nanorobots are simulated by a molecular dynamics (MD) model where FePd is a paramagnetic shape memory alloy that can exhibit phase transformation accompanied by softening of the nanohelix under an applied magnetic field (H-field). Two designs of FePd nanorobots are used: (i) a FePd cylindrical head connected to a FePd nanohelix tail and (ii) a FePd nanohelix alone. The geometry and dimensions of the FePd robots are taken after the as-processed FePd nanorobots. In the MD simulation, the FePd head and nanohelix are divided into a number of segmented FePd spheres, each having its magnetic moment. The results of the MD model reveal that upon the applied constant magnetic field, the initial gaps (g=3 nm) between the adjacent turns of the FePd nanohelix are closed, resulting in the total shrinkage (Stot) of 47 nm of the FePd nanorobot. The effects of the applied H-field on Stot are examined by using the MD model and the M-H curve of FePd fitted with Langevin type, resulting in the smaller applied magnetic field leading to the smaller Stot. The results of the MD model provide us with an effective tool in the analysis and design of new nanorobots based on the paramagnetic shape memory alloy of FePd nanohelices that can exert dynamic vibrations on target cells under the oscillating magnetic field. [ABSTRACT FROM AUTHOR]

In this paper, the elastic field in an infinite elastic body containing a polyhedral inclusion with uniform eigenstrains is investigated. Exact solutions are obtained for the stress field in and around a fully general polyhedron, i.e., an arbitrary bounded region of three-dimensional space with a piecewise planner boundary. Numerical results are presented for the stress field and the strain energy for several major polyhedra and the effective stiffness of a composite with regular polyhedral inhomogeneities. It is found that the stresses at the center of a polyhedral inclusion with uniaxial eigenstrain do not coincide with those for a spherical inclusion (Eshelby's solution) except for dodecahedron and icosahedron which belong to icosidodeca family, i.e., highly symmetrical structure. [DOI: 10.1115/1.1362670]

Research was conducted to study the structure of segregated networks in SiC/Si3n4 particulate composites. The SiC powders that were utilized as starting powders were mixed with Si3n4 powders in an ethanol solution to form green composite solids while the average of SiC particles were measured by scanning electron microscopy. Results indicated that composites with segregated distribution of conductive particles in an insulator matrix becomes electrically conductive at much smaller amount of conducting particle to form percolating networks.

An arbitrary, convex polygon-shaped inclusion with uniform eingenstrains was analyzed to determine its elastic fields under a plane strain condition. The elastic fields are obtained with the use of an extension of Mura's (1987) procedure. The strain concentration matrix is then calculated to obtain the overall elastic constants of composite materials with polygon-shaped reinforcements. The resulting strain fields and strain energy inside the inclusion as well as the stiffness of the composites are presented.

Analytical examination of the relaxation of misfit strains between ceramic/metal interfaces by dislocation punching in planar and nonplanar interfaces helps determine conditions essential for dislocation punching for each interface. Metal coating/ceramic substrate system forms the planar type interface while ceramic filler/metal matrix composite system forms the nonplanar interface. Agreement between experimental and theoretical results proves the efficiency of the dislocation punching model.

Four different aligned W-1% ThO2 reinforced Fe-25Cr-8Al-0.5Y matrix fiber reinforced superalloys exhibit varying metallurgical and mechanical properties. Three materials with different fiber aspect ratios and one material with a small diameter, misoriented Al2O3 hybrid reinforcement are studied. Abrasive waterjet and turning procedures help convert composite billets to tensile forms before a FeCrAlY thermal spray coat is used to prevent oxidation. Thermal residual stresses induce considerable nonlinearity in the material.

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Ferromagnetic shape memory alloy (FSMA) particulate composites have been processed by spark plasma sintering with varying weight fractions of NiTi (51 at. % Ni) and Fe powders. An assortment of experimental processing conditions such as temperature, pressure, duration of sintering, and heating rate has been chosen to characterize the relative density and superelasticity behavior of the said FSMA composite. The effective magnetic properties of these processed composites have also been experimentally estimated using vibrating sample magnetometry. An attempt at predicting the effective magnetic properties of the FSMA composite based on Eshelby’s inhomogeneous inclusion method in conjunction with Mori-Tanaka’s mean-field theory for larger concentrations of the ferromagnetic phase has also been presented in this study. The analytical model results thus obtained are compared with experimental data resulting in reasonably good agreement. [ABSTRACT FROM AUTHOR]

The aluminum matrix composite reinforced by short NiTi shape memory alloy fibers, NiTi/A16061 composite is fabricated using pressure-assisted sintering process in ambient air. It is observed that the composite is failed because of the strength mismatch between the NiTi fiber and aluminum matrix.

OBJECTIVE To evaluate effects of substituting mitoxantrone for doxorubicin in a cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapeutic protocol for first-line treatment of dogs with multicentric intermediate- to large-cell lymphoma. DESIGN Retrospective cohort study. ANIMALS 44 dogs treated with cyclophosphamide, mitoxantrone, vincristine, and prednisone (CMOP) and 51 dogs treated with CHOP at 12 referral institutions. PROCEDURES Medical records were reviewed to determine response to treatment, progression-free survival time, and overall survival time. For dogs treated with CMOP, adverse events were also recorded. RESULTS All 44 (100%) dogs treated with CMOP and 37 of 38 (97.4%) dogs treated with CHOP had a complete or partial response. Median progression-free survival time for dogs treated with CMOP was 165 days (95% confidence interval [CI], 143 to 187 days), and median overall survival time was 234 days (95% CI, 165 to 303 days). For dogs treated with CHOP, median progression-free survival time was 208 days (95% CI, 122 to 294 days), and median overall survival time was 348 days (95% CI, 287 to 409 days). Progression-free and overall survival times were not significantly different between groups. Overall, 9 of the 44 (20%) dogs treated with CMOP had adverse events likely or probably related to mitoxantrone, but all of these adverse events were mild. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that mitoxantrone may be a reasonable substitution in a CHOP protocol for treatment of dogs with multicentric intermediate- to large-cell lymphoma when doxorubicin is contraindicated. [ABSTRACT FROM AUTHOR]

The new technique to obtain the electroelastic field concentrations around ellipsoidal inhomogeneities in piezoelectric solid completely eliminates the necessity to solve complex fields outside the inhomogeneity. The electrostatic fields are determined as function of the inner electroelastic fields. This method finds applications in three-dimensional cavities and inhomogeneities, and also in the analysis of geometric and loading configurations.

Saito et al. (Modern Plastics 1997;74:175-7) have developed a low-cost transtibial prosthesis made of fiber-reinforced plastic (FRP). The prosthesis is comprised of an aluminum pylon, a cosmetic cover, and a constant cross-section composite foot into which aluminum supports are screwed to increase load-bearing capacity. Replacing these supports with a single integrated FRP stiffener significantly reduced manufacturing cost while providing high strength, great durability, and smooth walking. The optimal location and orientation of the proposed FRP stiffener were determined by finite element (FE) analysis. When a replica of this component was tested according to ISO standard 10328, the experimental prosthesis catastrophically failed under 6,600 N of force. Maximum percent error of strain between experimental and numerical results was 18.6%, showing good correlation between the two data sets. The optimized design provides sufficient strength and reduces the cost of manufacturing and thus can be used to replace the original design. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to analyse steady-state creep of a composite with spheroidal inclusions aligned along a tensile direction. It is an extension of a previous study of two-dimensional creep by Mori et al . (1997, Phil. Mag. Lett ., 75 , 359). As in the previous study, interfacial diffusion and sliding play essential roles in inducing steady-state creep. A new method of analysis is introduced. Basically, it calculates energy dissipation rates from the rates of diffusional flow and sliding. Both rates are geometrically connected to a creep rate, in a manner depending on the shape of inclusions. By specifying the matrix creep law, a simple relation between the steady-state creep rate and an external tensile stress is obtained. Coble creep is also analysed as a simple and extreme case to which the present method can apply: grains in a polycrystal are treated as inclusions and deformation of plastic character is achieved by boundary diffusion and sliding. [ABSTRACT FROM AUTHOR]

Presents an investigation of elastic fields in an inclusion with uniform eigenstrains under the condition of plane strain. Why are closed solutions obtained; Application of elastic properties of composite materials; Presentation of numerical examples.

A combined analytical/experimental study has been undertaken to in vestigate the effective thermal conductivity of hybrid composite materials. The analysis utilizes the equivalent inclusion approach for steady state heat conduction (Hatta and Taya, 1986), through which the interaction between the various reinforcing phases at finite con centrations is approximated by the Mori-Tanaka (1973) mean field approach. The multiple reinforcing phases of the composite are modeled as ellipsoidal in shape and thus can simulate a wide range of microstructural geometry ranging from thin platelet to con tinuous fiber reinforcement. The case when one phase of the composite is penny-shaped microcracks is studied in detail. Multiphase composites consisting of a Kerimid matrix and Al 2O3 short fibers and Si3N4 whiskers were fabricated and after a careful study of their microstructure, their thermal conductivities were measured. Analytical predictions are shown to be in good agreement with experimental results obtained for the Al2O 3/Si3N4/ Kerimid short fiber composites. [ABSTRACT FROM PUBLISHER]

The effect of variable fiber aspect ratio l/d on the thermo-mechanical properties of aligned short fiber composites is analytically studied by use of the Eshelby's equivalent inclusion method. Then, the thermo-mechanical properties of the composite predicted for a given density function (l/d) are compared with those obtained for the mean value of (l/d). Based on this comparison, the validity of using the mean value is discussed. As a demonstration, the results on two types of a short fiber composite are presented, SiC whisker/Aluminum and Carbon fiber/Epoxy composites. [ABSTRACT FROM PUBLISHER]