Effect of radiographic positioning on interpretation of cubital joint congruity in dogs

OBJECTIVE: To ascertain effects of x-ray beam centering and limb position on apparent congruity of a normal cubital joint (elbow). ANIMALS: 6 skeletally mature male Treeing Walker Coonhounds without physical, radiographic, or gross evidence of elbow abnormalities. PROCEDURE: Relative movement among humerus, radius, and ulna and measured joint space width on mediolateral and craniocaudal radiographic views was compared, using various x-ray beam centering and limb positions. RESULTS: Highest agreement and greatest certainty on subjective determination of congruity was for the flexed 90 degrees mediolateral radiographic view with the x-ray beam centered on the elbow. Distortion artifact of the proximal ulnar measurements was significant when the x-ray beam was centered on the midpoint of the radius. On the mediolateral view, the humeroradial joint space became significantly wide when the elbow was flexed. On the craniocaudal view, maximal humeroradial joint space width was obtained when the x-ray beam bisected the angle of the joint or was angled +30 degrees toward the humerus. CONCLUSIONS: Artifact distortion of joint width affected objective and subjective assessment of elbow congruity when the limb was placed in extreme flexion or extension or when the x-ray beam was not centered over the area of interest. Optimal visualization of the humeroradial joint space on the craniocaudal view was achieved when the x-ray beam bisected the angle of the elbow or was slightly angled toward the humerus. CLINICAL RELEVANCE: Elbow congruity was best assessed on the flexed 90 degrees lateral radiographic view with the x-ray beam centered on the joint.     

Assessment of childhood phobias

Childhood phobias can be successfully treated using a variety of behavioral strategies, provided there has been a psychometrically sound assessment. Measures are also important for the evaluation of treatment efficacy and the testing of hypotheses generated by new ideas and theories of children's phobias. This paper outlines broad-based assessment procedures used in the evaluation of children's phobias, including the behavioral or problem-focused interview, the diagnostic interview, self-report inventories, caregiver completed instruments, behavioral observations, self-monitoring and physiological assessment. Reflecting recent theoretical and clinical advances in the study of childhood internalizing disorders, we also explore laboratory-based measures and family assessment measures. Particular attention is given to psychometric issues and developmental sensitivity in our discussion of these assessment procedures.     

Functional properties of the acidic and basic subunits of the glycinin (11S) soy protein fraction

The functional properties of low- and high-M.W. (LMW and HMW, respectively) acidic subunits and the basic subunit separated from the 11S soy protein fraction were studied and compared with the functional properties of the 11S fraction. Among the functional properties investigated were solubility, emulsification, and viscosity. The results showed that the LMW acidic subunit had higher solubility than the HMW acidic subunit. Among all the samples, the LMW subunit separated by using β-mercaptoethanol (ME) was the most soluble, with a solubility of 98–100% at a pH of 6–12. The solubility profile of the HMW subunit followed a pattern similar to the solubility of 11S. The lowest solubility was observed around pH values in the range close to the isoelectric point for both the LMW and HMW subunit. The basic subunit was not soluble in the pH range 3–10; however, the solubility increased more than 50% at pH 13 compared to the solubility at pH 10. The emulsification capacity of all subunits was higher than 11S in the following descending order: LMW, basic, HMW, 11S. Emulsification activity and stability of the subunits were greater than those of the 11S samples at room temperature and 95°C. With the exception of the LMW subunit separated with ME, the subunits had a higher viscosity than 11S. The basic subunit separated with sodium bisulfite had the highest viscosity of all the samples tested.     

Cellulose acetate: Interactions with aqueous phenol and a transition temperature of about 20°C

Sorption of aqueous phenol onto powdered cellulose acetate can be described with the Langmuir equation at phenol concentrations below 0.10M. Unacetylated hydroxyl groups are probably the primary sites where phenol hydrogen bonds. As the phenol concentration is increased (> 0.13M), additional hydrogen bonding may occur with the carbonyl oxygens on the primary acetate groups, followed by secondary acetates and the beta glucosidic oxygens. Sorption at higher concentrations shows a negative slope for the Langmuir equation, perhaps caused by crowding and partial blocking of sites. Extrapolations to higher phenolic concentrations using the equation from the negative slope isotherm and plotting N versus °C reveal two lines with a point of intersection at 0.77M. Because of the increase slope above 0.77M, cellulose acetate may be dissolving in phenol. At concentrations below 0.10M, two processes were identified using a Van't Hoff plot (9.33 ± 0.30) × 10³ and (?1.36 ± 0.18) X 10³ J/mol. The initial moisture present in the polymer appears to be an important experimental variable and a transition temperature of 20.1 ± 0.2°C, probably due to polymer swelling, is reported.     

Thermal decomposition behavior of poly[3,3-bis(ethoxymethyl) oxetane] and related polyethers

The thermal decomposition behavior of poly[3,3-bis(ethoxymethyl)oxetane] (polyBEMO) was examined and compared to the decomposition of poly(ethylene oxide) (PEO) and poly(tetramethylene oxide) (polyTHF). Differential scanning calorimetric (DSC) studies as a function of heating rates and at constant temperature as a function of time yielded activation energies of 45–50 kcal/mol, characteristic of polyether decomposition. First-order decomposition kinetics were found. The reaction is endothermic, with a heat of decomposition of 18.6 kcal/mol. Effusion mass spectroscopy on polyBEMO showed major peaks at 112, 140, 168, and 174 amu. A mechanism is proposed in which the thermal scission of the ether bonds in both the polymer chain and in the appendanges initiates the decomposition. The main decomposition reaction for polyBEMO can be written as where the appendages and main chain are cleaved in an unknown order.     

Antinutritive and Oxidative Components as Mechanisms of Induced Resistance in Cotton to Helicoverpa zea

Induced resistance in cotton (Gossypium hirsutum) foliage and squares to herbivory by Helicoverpa zea (Lepidoptera: Noctuidae) is reported in this study. Induced resistance was indicated by decreased larval growth when larvae fed on previously damaged foliage or squares compared to the controls. Herbivory caused a significant decline in host nutritional quality as shown by a reduction in protein and most amino acids in both foliage and squares. Peroxidase, ascorbate oxidase, and diamine oxidase activities increased in both damaged foliage and squares, whereas levels of the nutritional antioxidant, ascorbate, were depressed after larval feeding. Larval feeding also markedly enhanced lipoxygenase activity and lipid peroxides in square tissues. Moreover, feeding damage altered the quantitative levels of phenolic compounds in foliage and squares. These results indicate a significant shift in the oxidative status of cotton plants following herbivory as indicated by increased oxidative enzyme activity, decreased levels of the nutritional antioxidant ascorbate, and increased levels of phenolic prooxidants (i.e., chlorogenic acid) and lipid peroxides.     

Tape Casting of Lanthanum Chromite

The effects of process additives, ball milling, and solids loading were evaluated for tape casting suspensions of glycinenitrate-synthesized La_0.7Ca_0.31CrO₃ powder. An optimized formulation was obtained based on rheological characterization, electrokinetic sonic amplitude measurements, qualitative examination of green tapes, and the sintered microstructure. The tape casting formulation incorporated 66:34 methyl ethyl ketone/ethyl alcohol solvent, an aliphatic phosphate ester dispersant, and 80 wt% (35 vol%) solids. The best binder/plasticizer system was 12 wt% (15 vol%) poly(isobutyl methacrylate) and 5 wt% (6.3 vol%) benzyl butyl phthalate plasticizer (binder:plasticizer = 2.3). Cast tapes were sintered at 1300°C for 2 h, producing a bulk density of 96.2% theoretical, with linear shrinkage of 22% and an approximate grain size of 1.3 μm.     

The mechanism of pleural inflammation by long carbon nanotubes: interaction of long fibres with macrophages stimulates them to amplify pro-inflammatory responses in mesothelial cells

Background

Little is known of how the toxicity of nanoparticles is affected by the incorporation in complex matrices. We compared the toxic effects of the titanium dioxide nanoparticle UV-Titan L181 (NanoTiO₂), pure or embedded in a paint matrix. We also compared the effects of the same paint with and without NanoTiO₂.

Methods

Mice received a single intratracheal instillation of 18, 54 and 162 μg of NanoTiO₂ or 54, 162 and 486 μg of the sanding dust from paint with and without NanoTiO₂. DNA damage in broncheoalveolar lavage cells and liver, lung inflammation and liver histology were evaluated 1, 3 and 28 days after intratracheal instillation. Printex 90 was included as positive control.

Results

There was no additive effect of adding NanoTiO₂ to paints: Therefore the toxicity of NanoTiO₂ was reduced by inclusion into a paint matrix. NanoTiO₂ induced inflammation in mice with severity similar to Printex 90. The inflammatory response of NanoTiO₂ and Printex 90 correlated with the instilled surface area. None of the materials, except of Printex 90, induced DNA damage in lung lining fluid cells. The highest dose of NanoTiO₂ caused DNA damage in hepatic tissue 1 day after intratracheal instillation. Exposure of mice to the dust from paints with and without TiO₂ was not associated with hepatic histopathological changes. Exposure to NanoTiO₂ or to Printex 90 caused slight histopathological changes in the liver in some of the mice at different time points.

Conclusions

Pulmonary inflammation and DNA damage and hepatic histopathology were not changed in mice instilled with sanding dust from NanoTiO₂ paint compared to paint without NanoTiO₂. However, pure NanoTiO₂ caused greater inflammation than NanoTiO₂ embedded in the paint matrix.     

Mechanical and thermal properties of polyphenylene sulfide/multiwalled carbon nanotube composites

Polyphenylene sulfide (PPS)/multiwalled carbon nanotube (MWCNT) composites were prepared using a melt‐blending procedure combining twin‐screw extrusion with centrifugal premixing. A homogeneous dispersion of MWCNTs throughout the matrix was revealed by scanning electron microscopy for the nanocomposites with MWCNT contents ranging from 0.5 to 8.0 wt %. The mechanical properties of PPS were markedly enhanced by the incorporation of MWCNTs. Halpin‐Tsai equations, modified with an efficiency factor, were used to model the elastic properties of the nanocomposites. The calculated modulus showed good agreement with the experimental data. The presence of the MWCNTs exhibited both promotion and retardation effects on the crystallization of PPS. The competition between these two effects results in an unusual change of the degree of crystallinity with increasing MWCNT content. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012