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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]

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]

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]

Discusses the formation of the segregated networks in SiC/Si3N4 particulate composite while examining the experimental and theoretical studies associated with this formation. Information on the proposed theoretical model; Estimation of the threshold particular loading for percolation; How the electronic composites have been used.

Abstract: The electrical and thermal conductivities of a silver flake/thermosetting polymer matrix composite were studied experimentally and analytically in terms of silver flake size and size distribution. The electrical volume resistivity and the steady-state thermal conductivity of the composite were measured at various silver flake loading. The analytical study was based on a three-dimensional resistor network model, which takes into account percolation and microscopic conduction mechanisms. The predictions based on the resistor network model were compared with the experimental data, resulting in a reasonably good agreement. It was found that flakes with smaller mean value in size and broader size distribution yield smaller threshold volume fraction of silver flake. It was shown that the predictions by the present thermal resistor network model yields better agreement with the experimental data than those by the effective medium theory such as Eshelby’s model, for a composite with high thermal conductivity ratio of filler to matrix. [Copyright &y& Elsevier]

Abstract: Wave field restoration has been achieved based on focal-depth extension under dynamic hollow-cone illumination using an optical microscope. Two kinds of focal-depth extension techniques, such as moving focus averaging and an objective annular aperture, were compared and their effectiveness for transmission electron microscopy applications is discussed. Both techniques enabled resolution enhancement at the same level and effectively obtained aberration-free phase and amplitude images separately by canceling out the rotationally invariant component of system wave aberrations, such as spherical aberration. The influence of nonlinear interference on image contrast was confirmed as significant by using a figure 8 shaped spatial frequency filter. [Copyright &y& Elsevier]

Abstract: The phase correction function used in the three-dimensional Fourier filtering method (3D-FFM) for compensating lens aberrations was investigated to reconstruct a high-resolution exit wave of a sample. An appropriate function, which hardly suffered from imperfect illumination conditions, was determined by comparing two types of phase correction functions with numerical calculations and experiments using through-focus images of an amorphous thin film and a [110]-oriented Si single crystal taken under tilted illumination or partially coherent illumination. Theoretical calculations indicated that a function in terms of w (an axial Fourier component), available uniquely in the 3D Fourier space, compensated for the phase shift due to the spherical aberration more precisely than did a conventional function in terms of g (the two-dimensional (2D) planar Fourier components). Experimentally, exit waves reconstructed using the w-function showed sample structures at ∼20% higher resolution than those reconstructed using the g-function. Image contrast simulations proved that the w-function had a significant advantage over the g-function: the former canceled out the effect of illumination divergence, resulting in a high-resolution exit wave. These results demonstrated that exit waves, which are uniquely realized in the 3D-FFM, should be reconstructed using the w-type phase correction function. [Copyright &y& Elsevier]

A new three-dimensional model for the strengthening mechanism of metal matrix composites reinforced by TiNi shape memory alloy (SMA) fibers has been proposed. The predicted results by the present model are compared with the experimental and the predicted results by a one-dimensional model from the literature. [Copyright &y& Elsevier]

Investigates the elastic field in an elastic body containing a polyhedral inclusion with uniform eigenstrains. Solutions obtained for the stress field in and around a general polyhedron; Subdivisions of the surface of the polyhedron; Results and discussion for polyhedral inclusions.

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 micro-temperature sensor array with thin-film thermocouples (TFTCs) is developed. The TFTCs are made with T-type (copper-constantan) thermocouples to measure chip temperature distribution of electronic packaging. The sensor array of 150 nm thickness has 10 × 10 junctions within a 9 × 9 mm area. [ABSTRACT FROM AUTHOR]

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]

Abstract: This review article presents an outlook on the current strategies and existing concepts for culture surface designs to regulate cell morphologies and functions. First, cell structures and cell attachment behaviors are described in relation to the interactions between cells and their surroundings. Next, various surface designs are addressed, with a summary of the current topics of particular interest. The architectural features of substrates can be controlled to facilitate the quest for design principles including material choices and geometric modifications. In addition, various types of biomolecules, such as adhesive elements and growth factors, can be incorporated to regulate cell behaviors, including cell attachment, growth and differentiation. It is possible to manipulate these surface variables to produce desired surface designs for inducing cellular responses. In the latter part of this article, the topics discussed involve dendrimer-immobilized surfaces designed in authors'' studies dealing with the in vitro culture processes of differentiated and undifferentiated cells. This article will offer novel insights into the processing of cells and tissues toward therapeutic applications in regenerative medicine. [Copyright &y& Elsevier]

Abstract: Solid solution (1− x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 shows high dielectric constant near room temperature and is an ideal capacitor material. The composition 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3, which is located near the morphotropic phase boundary, were densified by the spark-plasma-sintering method at an ultra-low temperature (700°C). Dielectric constant measurement shows that the thus prepared sample shows higher dielectric constant at room temperature and good temperature stability in a wide temperature range. The behavior is much different from that of samples sintered by conventional method and could be ascribed to size effect. [Copyright &y& Elsevier]

The aluminum matrix composite reinforced by short NiTi shape memory alloy fibers, NiTi/A16061 composite, was fabricated using pressure-assisted sintering process in ambient air Surface preparation and thermal pretreatment of NiTi fibers essential for solid state bonding of TixA1y intermetallic compound were carried out. Strong interface bonding between NiTi fiber and A16061 matrix was obtained. The strengthening mechanism of shape memory effect associated with short fiber reinforcement was theoretically examined by extending Taya's previous model. The stress-strain behavior of the short fiber-reinforced NiTi/A16061 composite was investigated at room and elevated temperature both experimentally and analytically. In order to activate the shape memory effect, the composite was prestrained at a temperature between martensite start temperature M3 and austenite start temperature As' then yield stresses as a function of the prestrain were tested and predicted at a temperature above the austenite finish temperature Af. It was found that: (1) the yield stress of the composite increased with increasing the amount of prestrain; (2) the prestrain value should not exceed 0.01, to make use of strengthening of the composite without loss of the ductility of the matrix; and (3) failure of the composite was caused by the strength mismatch between the NiTi fiber and aluminum matrix. [ABSTRACT FROM AUTHOR]

This paper presents a simple method to examine whether a ferromagnetic shape memory alloy can be used as an actuator by controlling the transformation temperature by magnetic field. Both Fe–Pd and NiAlCo alloys are studied. The analysis results show the recently discovered alloy of NiAlCo cannot be used. Although an Fe–Pd alloy can be used, in principle, for magnetic field actuation, the work extracted by magnetic actuation is small. [Copyright &y& Elsevier]