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Concerns over livestock production practices have resulted in increased consumer preferences for certified products. Australian beef buyers' survey data revealed the preferences of consumers who would buy differentiated beef based on animal welfare, safety, health, or environmental -friendly considerations. Female respondents are more likely to buy certified animal welfare products. Buyers with children, and those who value branded beef, are more likely to buy products differentiated by a bundle of credence attributes. Given that Australian beef consumers eat similar amounts, there are opportunities for differentiating beef products according to credence attributes and offering them in a range of retailers. [ABSTRACT FROM AUTHOR]

Accepting that increased climate variability will require that farmers make significant changes to their farm systems, we can see that maintaining flexibility is an important coping strategy. Using general systems theory, we offer a conceptual model for describing the tactical and strategic flexibility of farm systems to reveal the sensitivity of farm systems to variable critical inputs. The model is used to classify farm systems as rigid, robust, or elastic on the basis of two factors, the capacity of the farmer to reduce reliance on critical inputs by altering the following: (i) the use of critical inputs and (ii) farm output. The different production emphasis for the different types of systems has implications for how these farmers are able to respond to increased variability and on public policies that may support viable farm businesses in the face of increased variability. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents a study on the diagnostic accuracy of bright-blood T2-weighted cardiac magnetic resonance imaging (MRI) for myocardial hemorrhage in experimental myocardial infarction (MI) in swine. The study involved 15 swine where MI was created by occluding the left anterior descending or circumflex coronary arteries. Findings reportedly indicate that bright-blood T2-weighted MRI has a high diagnostic accuracy for myocardial hemorrhage.

The regional distribution of skeletal muscle blood flow was measured during postischemic reactive hyperemia using Gd-DTPA contrast-enhanced (CE) MRI. The release of an occlusive thigh cuff was used to deliver a step-input of contrast concentration that was coincident with the onset of reactive hyperemia. A first-order tracer kinetic equation was used to estimate the unidirectional influx constant, K i (ml/100 g/min), and the distribution volume of Gd-DTPA in the tissue, v e, from T1-weighted images acquired with saturation recovery (SR) steady-state free precession (SSFP) and spoiled gradient-echo (SPGR) protocols. The capillary permeability surface (PS) area increased significantly during reactive hyperemia, which facilitated rapid extraction of Gd-DTPA during the first pass. Regional muscle group studies from 11 normal volunteers yielded blood flow ( K i) values of 108.3 ± 34.1 ml/100 g/min in the gastrocnemius, 184.3 ± 41.3 ml/100 g/min in the soleus, and 122.4 ± 34.4 ml/100 g/min in the tibialis anterior. The distribution volumes ( v e) in the corresponding muscle groups were respectively 8.3% ± 2.1%, 9.3% ± 1.9%, and 7.9% ± 1.8% from the kinetic model, and 8.8% ± 2.4%, 9.1% ± 1.9%, and 7.2% ± 1.4% from tissue relaxometry studies. Bulk blood flow studies in the same volunteers using phase-contrast velocimetry (popliteal artery) yielded significantly lower flow values, but with a correlation coefficient R2 = 0.62 and P = 0.004. Magn Reson Med 54:289-298, 2005. Published 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Glutamate dehydrogenase (GDH) isoenzymes were purified from control, and ribonucleoside triphosphate (NTP)-treated peanut seedlings. GDH purification was by preparative-scale, free solution isoelectric focusing, followed by native PAGE, and the cryoelectrophoretic elution of the isoenzymes from the gel. SDS-PAGE of the purified GDH isoenzymes, followed by either silver staining of the gel, or western analysis using anti-GDH antibody, gave identical GDH polypeptide (a, α, and b) bands, thus, confirming the purity of the isoenzymes. The substrate specificities in the aminating activity of the GDH isoenzymes, or disaggregated polypeptides were determined by photometry, but the substrate specificities in the RNA synthesis activity were determined in cocktails containing 0.06–0.8 mM of each of UTP, ATP, GTP, and CTP, 0–100.0 mM NH4Cl, 0–50.0 mM α-ketoglutaratr (α-KG), 0–0.2 mM NADH, 0–10.0 mM CaCl2 5 units of DNase 1, antibiotics, and ∼5 µg pure GDH isoenzymes or polypeptides at pH 8.0, and overnight at 16°C. The GDH polypeptides were active only in amination reaction, but the GDH isoenzymes were active in both amination and RNA synthesis. Whereas, NADH, NH4Cl and α-KG served as the substrates for the amination reaction, and as modulators in the RNA synthetic reaction, ATP, GTP, UTP, and CTP served as substrates for the isoenzymes in RNA synthesis reaction. The product RNA was up to 2 µg µg-1 GDH, and consisted of RNA species in the size ranges of 26, 16, and 5 S rRNAs. DNAse 1 in the assay cocktail ruled out transcription as the mechanism of the RNA synthesis. Addition of [α-32P] NTP led to the production of labeled RNA, thus confirming the specificity of NTPs as substrates, and that the RNA was not pre-existing in the reaction cocktail. [ABSTRACT FROM AUTHOR]

The article reports on doctor Victor Wright, a 2006 Australian Agricultural and Resource Economics Society Inc. (AARES) distinguished fellow. He has worked at the interface between agricultural marketing and business marketing, farm management, and general management, at the University of New England.

Abstract: Australian beef consumers have different preferences given their characteristics and the effect on expected quality of cues related to health, production process and eating experience. Beef brands using Meat Standards Australia (MSA) grades can help to signal quality and reduce consumers'' uncertainty when shopping. The objective of this study is to identify the characteristics of beef buyers and their perceptions about product attributes that affect the propensity to buy branded beef. Binary logistic models were applied identifying differences between all respondents and the potential target market, including buyers in medium to high income segments, and between buyers in the target market who would buy branded beef for taste and health reasons. Variables increasing the propensity to buy branded beef include previous experience, appreciation for branded cuts and concern about quality more than size. Finally, variations in preferences for marbling and cut were found between buyers who would buy branded beef for taste and health reasons. [Copyright &y& Elsevier]

Objectives: We developed and tested a novel transcatheter circumferential annuloplasty technique to reduce mitral regurgitation in porcine ischemic cardiomyopathy. Background: Catheter-based annuloplasty for secondary mitral regurgitation exploits the proximity of the coronary sinus to the mitral annulus, but is limited by anatomic variants and coronary artery entrapment. Methods: The procedure, “cerclage annuloplasty,” is guided by magnetic resonance imaging (MRI) roadmaps fused with live X-ray. A coronary sinus guidewire traverses a short segment of the basal septal myocardium to re-enter the right heart where it is exchanged for a suture. Tension is applied interactively during imaging and secured with a locking device. Results: We found 2 feasible suture pathways from the great cardiac vein across the interventricular septum to create cerclage. Right ventricular septal re-entry required shorter fluoroscopy times than right atrial re-entry, which entailed a longer intramyocardial traversal but did not cross the tricuspid valve. Graded tension progressively reduced septal-lateral annular diameter, but not end-systolic elastance or regional myocardial function. A simple arch-like device protected entrapped coronary arteries from compression even during supratherapeutic tension. Cerclage reduced mitral regurgitation fraction (from 22.8 ± 12.7% to 7.2 ± 4.4%, p = 0.04) by slice tracking velocity-encoded MRI. Flexible cerclage reduced annular size but preserved annular motion. Cerclage also displaced the posterior annulus toward the papillary muscles. Cerclage introduced reciprocal constraint to the left ventricular outflow tract and mitral annulus that enhanced leaflet coaptation. A sample of human coronary venograms and computed tomography angiograms suggested that most have suitable venous anatomy for cerclage. Conclusions: Transcatheter mitral cerclage annuloplasty acutely reduces mitral regurgitation in porcine ischemic cardiomyopathy. Entrapped coronary arteries can be protected. MRI provided insight into the mechanism of cerclage action. [Copyright &y& Elsevier]

Purpose: Magnetic resonance imaging (MRI) provides superior visualization of the prostate and surrounding anatomy, making it the modality of choice for imaging the prostate gland. This pilot study was performed to determine the feasibility and dosimetric quality achieved when placing high-dose-rate prostate brachytherapy catheters under MRI guidance in a standard “closed-bore” 1.5T scanner.Methods and materials: Patients with intermediate-risk and high-risk localized prostate cancer received MRI-guided high-dose-rate brachytherapy boosts before and after a course of external beam radiotherapy. Using a custom visualization and targeting program, the brachytherapy catheters were placed and adjusted under MRI guidance until satisfactory implant geometry was achieved. Inverse treatment planning was performed using high-resolution T2-weighted MRI.Results: Ten brachytherapy procedures were performed on 5 patients. The median percentage of volume receiving 100% of prescribed minimal peripheral dose (V100) achieved was 94% (mean, 92%; 95% confidence interval, 89–95%). The urethral V125 ranged from 0% to 18% (median, 5%), and the rectal V75 ranged from 0% to 3.1% (median, 0.3%). In all cases, lesions highly suspicious for malignancy could be visualized on the procedural MRI, and extracapsular disease was identified in 2 patients.Conclusion: High-dose-rate prostate brachytherapy in a standard 1.5T MRI scanner is feasible and achieves favorable dosimetry within a reasonable period with high-quality image guidance. Although the procedure was well tolerated in the acute setting, additional follow-up is required to determine the long-term safety and efficacy of this approach. [Copyright &y& Elsevier]