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Given the limited availability of fresh osteochondral allografts and uncertainty regarding performance of decellularized allografts, this study was undertaken as part of an effort to develop an osteochondral xenograft for articular cartilage repair. The purpose was to evaluate a simple antigen removal procedure based mainly on treatment with SDS and nucleases. Histology demonstrated a preservation of collagenous structure and removal of most nuclei. Immunohistochemistry revealed the apparent retention of α-Gal within osteocyte lacunae unless the tissue underwent an additional α-galactosidase processing step. Cytoplasmic protein was completely removed as shown by Western blot. Quantitatively, the antigen removal protocol was found to extract approximately 90% of DNA from cartilage and bone, and it extracted over 80% of glycosaminoglycan from cartilage. Collagen content was not affected. Mechanical testing of cartilage and bone were performed separately, in addition to testing the cartilage-bone interface, and the main effect of antigen removal was an increase in cartilage hydraulic permeability. In vivo immunogenicity was assessed by subcutaneous implantation into DBA/1 J mice, and the response was typical of a foreign body rather than immune reaction. Thus, an osteochondral xenograft produced as described has the potential for further development into a treatment for osteochondral lesions in the human knee. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2251-2260, 2018.

Osteochondral xenografts are potentially inexpensive, widely available alternatives to fresh allografts. However, antigen removal from xenogenic cartilage may damage the extracellular matrix and reduce compressive stiffness. Non-crosslinked xenogenic cartilage may also undergo rapid enzymatic degradation in vivo. We hypothesized that natural crosslinking agents could be used in place of glutaraldehyde to improve the mechanical properties and enzymatic resistance of decellularized cartilage. This study compared the effects of genipin (GNP), proanthocyanidin (PA), and epigallocatechin gallate (EGCG), on the physical and mechanical properties of decellularized porcine cartilage. Glutaraldehyde (GA) served as a positive control. Porcine articular cartilage discs were decellularized in 2% sodium dodecyl sulfate and DNase I followed by fixation in 0.25% GNP, 0.25% PA, 0.25% EGCG, or 2.5% GA. Decellularization decreased DNA by 15% and GAG by 35%. For natural crosslinkers, the average degree of crosslinking ranged from approximately 50% (EGCG) to 78% (GNP), as compared to 83% for the GA control. Among the natural crosslinkers, only GNP significantly affected the disc diameter, and shrinkage was under 2%. GA fixation had no significant effect on disc diameter. Decellularization decreased aggregate modulus; GA and GNP, but not EGCG and PA, were able to restore it to its original level. GNP, PA, and GA conferred a similar, almost complete resistance to collagenase degradation. EGCG also conferred substantial resistance but to a lesser degree. Overall, the data support our hypothesis and suggest that natural crosslinkers may be suitable alternatives to glutaraldehyde for stabilization of decellularized cartilage. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1037-1046, 2016.

Heat transfer coefficients to canned Newtonian and non-Newtonian liquids were determined in a Steritort. Dimensionless correlations of the form, NUD= A1 (Gr PI)A2+ A3 (ReD Pr L/D)A4 correlated well the data. The diameter of the can was the characteristic dimension and the properties of each fluid were evaluated at the average of its initial and final temperatures. The contribution of free convection was significant (44 - 97%). The data with non-Newtonian fluids were correlated using the generalized Reynolds number (ReD), and the Prandtl and the Grashof numbers based on the apparent viscosity in ReD. It appears that the mechanism of heat transfer was also changed by conduction in the case of a 0.75% sugar gum solution whose consistency index of the power law model was about 0.9N sn/m2 at 6°C.

A pregnant quarterhorse mare became acutely lame as a result of severe swelling of its right hind leg, thought to have been caused by a fracture or a muscle tear. Diagnostic procedures ruled out a traumatic musculoskeletal cause and a physical examination revealed chronic pastern dermatitis ('scratches'/'grease heel'). Histopathological evaluation of biopsy samples from the right hind leg was consistent with a leucocytoclastic vasculitis, and culture yielded Staphylococcus intermedius. The treatment and infectious causes of pastern dermatitis are discussed.

A direct-drive concentric cylinder viscometer in a pressure chamber was used to study the flow behavior of a 11 Brix tomato puree at several temperatures in the range: 76 to 120C. The activation energy of flow of the tomato puree, based on apparent viscosity at 50 s -1 , was: 9.4 kJ mol -1 . The apparent viscosity (η a ) versus temperature profiles of a 4.0% waxy rice (WR) starch dispersion were determined during continuous heating from 30 to 110C at six shear rates in the shear range: 114 to 644 s -1 ; beginning at about 95C, significant increase in η a was observed at 114 and 160 s -1 . The said profiles collapsed to a single curve when η a values were converted to reduced viscosity, η aR =η a (γ -γt ). Values of η a of the starch dispersion were lower than those of η * at about the same shear rates, γ=5.7 s -1 and ω=6.3 rad s -1 .

A young labrador dog had a rapidly enlarging osteolytic lesion of the left maxillary bone. The histological diagnosis was central giant cell granuloma. This is a benign, non-neoplastic lesion that has some radiographic and histological similarities to malignant bone tumours of this region. The importance of biopsy in making the diagnosis is emphasised because surgical treatment of central giant cell granuloma by resection or curettage usually resolves these lesions.

An 11-year-old mixed breed dog was referred because of coughing and painful swelling of the distal extremities which had not resolved with antibiotic treatment. A consolidated left cranial lung lobe and hypertrophic osteopathy were identified by radiographs. A unique feature of this report is the marked, rapid reduction in pain and lameness associated with hypertrophic osteopathy after treatment with corticosteroids. Histological examination of an 8 cm diameter, spherical mass found in the excised cranial lung lobe revealed osteosarcoma. No evidence of local or distant metastases was present. The dog survived one year after diagnosis.

High-methoxyl (HM) pectin/sugar gels are viscoelastic materials whose elastic (storage modulus, G′) and viscous (loss modulus, G″) characteristics can be measured by dynamic rheological technique. At 10C, over the frequency range 0.1–10 Hz, magnitudes of G′ and G″ of glucose gels were higher than those of fructose gels. Magnitudes of G′ and G″ of both sugar gels increased with pectin concentration according to power laws; the increase in G′ was higher than that of G″. Much useful information on food gels can also be obtained by following the sol-gel transition process. Complex viscosity (η*) at 1 Hz was used to follow structure development (SD) and SD rate during sol-gel transition of pectin-fructose/glucose dispersions. Integrated average viscosities and SD rates were also higher for glucose gels than for fructose gels.

Incipient structure development (SD) in 65% fructose-0.5, 0.75, and 1% high-methoxyl (HM) pectin gels (pH 2.7) being cooled (5010 o C) were measured in terms of dynamic viscosity (η * ) at 1 Hz. SD rates (poise/min) were higher at lower temperatures, higher pectin concentrations, and when pectin was hydrated for 16 hr. Below the gel temperature, SD rates in 1% gel followed the Flory-Weaver model. SD in stored 0.5% gels during 22 days was strongly affected by storage temperature (2-38 o C) and pH. SD rates in pH 2.7 gels were positive above, but negative below 18 o C

Gels made with 0.5% and 1% pectin in 60% fructose, and a commercial sample exhibited macromolecular solution/weak gel behavior. Cooling the gels from 50–10°C increased storage (G') and loss moduli (G') of the gels. As the rate of cooling (10, 5.7, and 2.5°C/hr) a 1% pectin, 60% fructose, dispersion increased, the elasticity of the formed gel decreased; however, G' was not affected much by rate of cooling. During the first 24 hr, the changes in G'and G' were small. After 14 days storage at ambient temperature, G’values of gels increased substantially, while G' values increased slightly.

Tomato pastes (26–30 °Brix) at 40C were highly shear thinning fluids (n = 0.28) with large magnitudes of Casson yield stresses (78–212 Pa). Dynamic shear data revealed weak gel-like behavior of the pastes: magnitudes of G′ were higher than those of G″, and both increased with oscillatory frequencies. The Cox-Merz rule was not applicable to the steady and dynamic shear data on the pastes, but the two types of data conformed with the use of shift factor on frequency. Solids and liquid fractions in the pastes were satisfactory for correlating the dynamic properties, consistency index, and Casson yield stress.

The stress-volume characteristics of crushed grape cultivars: Baco Noir, Cabernet Sauvignon, Catawba, Cayuga White, Chardonnay, Concord, Delaware, Melody, Niagara, Johannisberg Riesling, and Seyval Blanc, with and without paper and rice hulls press aids were studied in an expression cell and an Instron Universal Testing Machine. the slopes of ln stress vs volume in compression were significantly (P< 0.001) dependent on the grape cultivar. Addition of 1–3% press aid by weight decreased the magnitudes of slopes by about 11% with Seyval Blanc to about 51% with Catawba; i. e., the ease with which pressing could be performed increased with the addition of press aid. With Cabernet Sauvignon grapes, addition of press aid 0.5, 1.0, and 2.0% resulted in increase in slopes ranging between 14.7 and 24.9%. the slopes of the ln stress-ln time during the relaxation portion of the experiment were also significantly dependent (P< 0.001) on the grape cultivar; the magnitudes of the slopes increased with the addition of 1–3% paper press aid. the juice yields were affected significantly (P< 0.001) by the addition of paper press aid, with maximum yields being obtained when 1–2% (w/w) paper press aid was added. As expected, juice yields (w/w%) were significantly dependent (P< 0.001) on grape cultivars.

The work described here demonstrates the synthesis by human articular cartilage of plasminogen activator inhibitor-1 (PAI-1), a potent inhibitor of the serine protease tissue plasminogen activator (tPA). We also present data demonstrating an increase in PAI-1 messenger ribonucleic acid (mRNA) in chondrocytes exposed to the cytokine interleukin-1 (IL-1). Interestingly, this elevation of steady-state mRNA levels does not appear to result in an increase in synthesis of PAI-1 protein. Northern blot analysis reveals that of the two mRNA species (3.4 kb, 2.4 kb) previously reported for PAI-1, only the larger species (3.4 kb) appears to be synthesized by chrondrocytes. Our data demonstrate the IL-1-stimulated production by cartilage of tissue plasminogen activator. We also show evidence for the presence of plasminogen in cartilage. A scheme is presented indicating the probable importance of the serine proteases (tPA and plasminogen) and PAI-1 in cartilage degradation.

Two dogs with supraspinatus calcifying tendinopathy were lame in their forelimbs and were treated by the surgical excision of the calcified lesion. The lameness in both dogs improved after surgery without additional medical treatment, as evidenced by force-plate analysis of their gait.

An intra-abdominal testicular tumour was diagnosed in a 10-year-old, male, cryptorchid golden retriever. Upon surgical removal, torsion of the testis was found. The histopathological diagnosis was seminoma. The ultrasound examination in this case revealed a parenchymal mass lesion. An ultrasound examination is a useful supplemental diagnostic tool for differentiation of abdominal mass lesions.

Shear rate-shear stress data on about fifty tomato concentrates were employed to study the applicability of three flow models: Herschel-Bulkley (H-B), Mizrahi-Berk (M-B), and Vocadlo. The magnitudes of the three parameters of each model were determined by means of nonlinear regression analysis. The H-B and M-B models described very well the flow data. The logarithm of the apparent yield stress values predicted by each model and total solids of the concentrates were related by a quadratic equation. The magnitudes of the flow behavior index of each model did not change significantly over the total solids range studied: 6–36%. The consistency index of the Vocadlo and H-B model, and the concentration of the tomato concentrates were related by a power relationship. Over the temperature range 15–55°C, the flow behavior index of each model did not change significantly. The yield stress decreased with increase in temperature reaching a nearly constant value at 55°C. The consistency index of each model and temperature could be correlated by the Arrhenius equation.

Shear rate-shear stress data of 54 samples of apple sauce and their serums were determined, and power law parameters were derived for the data. The samples were from two apple cultivars (Rome Beauty and Rhode Island Greening) that were stored to three firmness values and processed utilizing three finisher screen sizes and speeds. Serum samples were mildly non-Newtonian, while the sauce samples were highly non-Newtonian fluids. Analysis of variance showed that apple cultivar, apple firmness and finisher screen opening accounted for a large variation in sauce consistency, while regression analysis showed that pulp content was important for the magnitude of the sauce consistency.

The application of optimization techniques in digital simulation experiments is frequently complicated by the presence of large experimental error variances. Two of the more widely accepted design strategies for the resolution of this problem include the assignment of common pseudorandom number streams and the assignment of antithetic pseudorandom number streams to the experimental points. When considered separately, however, each of these variance-reduction procedures has rather restrictive limitations. This paper examines the simultaneous use of these two techniques as a variance-reduction strategy in response surface methodology (RSM) analysis of simulation models. A simulation of an inventory system is used to illustrate the application and benefits of this assignment procedure, as well as the basic components of an RSM analysis.

Therapeutic relationship as perceived by clients (N = 54) and therapists (N = 8) At a community mental health clinic was rated on Lorr's (1965) five main factors: Understanding, Accepting, Accepting, Critical, Independence-Encouraging, and Authoritarian (directive). These perceptions were correlated with client and therapist ratings of improvement. In addition, discrepancies between client and therapist ratings of the relationship were correlated with outcome measures. Findings indicated that client perceptions of therapists as Understanding and Accepting were correlated most highly with self-reported improvement. Therapists self-perception of Independence-Encouraging was correlated most highly with client-rated improvement, while therapists' self-perception of Accepting and Understanding was correlated most highly with therapist-rated improvement. Differences between client and therapist ratings of the Understanding and Accepting qualities of the therapeutic relationship showed the highest negative correlations with both client and therapist improvement ratings. Implications for therapeutic and research strategies are discussed.

Prolonged heat treatment of 1% (w/v) guar gum and sodium carboxymethylcellulose (CMC) solutions resulted in a permanent loss of their apparent viscosity. The consistency index (K) of the power law model: τ= K γn, indicated well the loss of viscosity. The reduction in K due to heat treatment could be characterized by D and z parameters. The D250 and z values for guar gum were 32 min and 62°F, respectively; the magnitudes for CMC were 7.9 min and 48°F, respectively. These values were obtained from experiments in which the solutions were placed in sealed cans (201 × 304) and subjected to temperatures between 210–260°F. Because the solutions were viscous, corrections were made for heating and cooling lags during heat treatment. Dilutee solution viscosity data showed that heat treatment resulted in lower magnitudes of intrinsic viscosities and interaction coefficients. The activation energy of flow of the heat-treated solutions was not affected significantly due to heat treatment.

The analysis of simulation data in the evaluation of competing alternatives presents a problem for the analyst using conventional statistical techniques. The assumptions of normality and common variances generally cause difficulties since many classes of simulation experiments typically violate both of these assumptions. In addition, the analyst is usually interested in comparing competing alternatives using environments that are as close to identical as possible. In these situations, blocking is desirable and can usually be accomplished by using common random number streams. This paper discusses a distribution-free method based on Friedman's rank sums test that can be used to analyze simulation results exhibiting the above characteristics. The procedure requires only independence within treatments.

The flow properties of over seventy concentrates made from four cultivars of tomatoes were determined with a concentric cylinder viscometer. The apparent viscosity (100 s−1, 25°C) of the concentrates of each variety was proportional to the 2.5 power of the concentration (% total solids). The apparent viscosity of the Nova cultivar obeyed the Arrhenius temperature relationship; the activation energy for the concentrates was 2.3 ± 0.3 kcal/mole. The simple power law and the Casson model described satisfactorily the flow data of the concentrates but the power law gave higher correlation coefficients. The Herschel-Bulkley model with the Casson yield stress was also satisfactory but the correlation coefficients were lower than for the simple power law. The consistency index of the power law model also showed a power dependence on the concentration. The natural logarithm of the yield stress and the concentration could be correlated by a quadratic equation.

In a creep-compliance test, the strain due to an imposed stress is recorded as a function of time. Subsequently, the strain is converted to creep-compliance and the rheological parameters: compliances, retardation times, and viscosities are evaluated by a graphical method suggested by Inokuchi. A Macintosh Plus microcomputer was programmed in Basic language to collect time-strain data from a Deer Rheometer III. A Fortran language program was written first to compute creep-compliance from strain and subsequently to estimate rheological parameters using a nonlinear parameter estimation subroutine. Initial values for the nonlinear analysis were estimated by the computer program by means of a modified Inokuchi's method.

Kinetic parameters were determined for the loss of color and firmness of snap beans during thermal processing. The D250 and the z-values for the loss of color were found to be 12.6 min and 91°F, respectively. Firmness loss was determined as the peak back extrusion force. The D250 and the z-values for the loss of firmness were 3.4 min and 106°F, respectively. The magnitudes of the kinetic parameters are in the range of values reported in the literature.

The effective shear rates of a flag and a star shaped impeller were determined in a jacketed vessel by matching the viscosity of a Newtonian fluid and the apparent viscosity of a non-Newtonian fluid, and from the slope of a plot of (1–n) versus log (P/K Nn+1d3). The results from the two methods were in good agreement. For geometries with large surface areas, the method of matching viscosities is less likely to contribute to errors.

Texture profile analysis (TPA) parameters were determined with a Voland-Stevens Texture Analyzer-1000 (VSTA) and an Instron Universal Testing Machine. Because of the nature of the design of VSTA, reliable magnitudes of TPA parameters based on the force-time curves recorded during the down stroke can be calculated. With a 2.54 cm diameter plexiglas plunger, the TPA parameters with the VSTA were higher than those with the Instron by 1.45% for hardness to 16.1% for fracturability.

Since mint oil is used as a flavouring agent for foods and cosmetics, pesticide residues in the oil are undesirable. The residual behaviour of two pesticides, phorate and methomyl, was studied as replacements for chlorinated hydrocarbon pesticides which leave residues in the oil. Phorate applications of 1.1 kg/ha resulted in oil residues of 0.24 mg/kg total phorate in Oregon samples and 1.69 mg/kg in Washington samples. Less than 1% of the residues in the hay distilled with the oil. Mint oil undergoes a 100- to 1000-fold dilution in commercial use with a corresponding reduction of residues in the final product. No residues of methomyl were found in the oil, even with hay residues as high as 5.34 mg/kg. Residues in hay decreased to half of initial levels in 2 to 4 days, independently of use conditions. It was concluded that the proposed use of phorate or methomyl for control of mint pests does not present a residue hazard. Details of the analytical methods used are also presented.

Apple pomace was subjected to a mild alkaline degradation that yielded an cu-cellulosic fraction of approximately 26% of the untreated dry matter. Extraction by various aqueous solvents yielded water-dispersible, uronide fractions comprising 10 - 18% also of the untreated dry matter. These latter fibers had a different viscometric character, depending on the extractant used. All the fibers have the potential to provide nonnutritive bulk to low-fiber, fabricated foods. Additionally, they may provide a high concentration of solid matter to an aqueous, food system without significantly altering the viscosity of that system.

Fresh apple juice was clarified in a pilot scale ultrafiltration (UF) unit, with membranes made of polysulfone and polyamide and plate and frame and vacuum drum filters. Flux of apple juice (L/m2 hr) vs UF transmembrane pressure data showed an optimum at a pressure of about 140 kPa. Retention of odor-active volatiles was highest in plate and frame filtered apple juice and lowest in vacuum drum filtered juice; the retention of odor-active volatiles in UF juice was intermediate to the two traditional filtration methods. Retention of odor-active volatiles in the permeate of a polyamide membrane was higher than that of a polysulfone membrane.

Steam consumption for a water blancher and a continuous pressure sterilizer (CPS) was measured in a snap bean cannery. For the blancher, it ranged between 0.204 and 0.306 lb/lb of beans. The energy efficiency of the blancher was found to be between 26.3–52.3%. In a pilot scale test, the concentration of Ca, Mg, and K ions increased as the blanching water was recycled and the firmness of the beans after canning varied between 0.855 and 1.010 kN. Steam consumption by the CPS was related linearly to the loading rate of cans: steam consumed (lb/hr) = 1075.9 + 0.073 × (cans/hr).

The kinetic parameters, D and z, for the loss of color, firmness, and vitamin C were determined during the thermal processing of peas canned in 303 × 406 cans. The D250 values for loss of color, firmness, and vitamin C were 13.2 min, 9.2 min, and 246 min, respectively. The corresponding z values were: 69°F, 66°F, and 91°F, respectively. These results are in good agreement with those reported in the literature. With proper precautions and corrections for lags, kinetic parameters for the loss of quality parameters can be determined during thermal processing of foods in relatively large cans.

* A recent survey of real estate investment trust (REIT) advisory compensation shows that more than half of these institutions currently use some form of incentive compensation. This compensation structure typically provides some base payment plus a participation in net income, generally when it exceeds some minimum level. The asymmetry present in incentive compensation will be shown to create incorrect motivations for the REIT advisor.