Effects of autografting ovarian tissue,ovariectomy and implanting on growth rate and carcass characteristics of feedlot heifers

Ninety heifers sired by Charolais or Red Poll bulls were utilised in two trials involving ovariectomy, ovarian tissue transplants (autografts) andlor an anabolic implant. In trial 1, four treatments were imposed upon 60 heifers: (1) autograft, (2) autograft plus Synovex-H® implant, (3) vaginal ovariectomy plus implant, and (4) intact plus implant. Three replications of five heifers per treatment were fed a finishing diet until heifers weighed approximately 432 kg. Autografed-implanted heifers exhibited a greater average daily gain than non-implanted autografted heifers (P < 0.05). No treatment effects were detected for feed eficiency or dressing percentage. Carcasses from autografted heifers merited higher marbling scores and USDA quality grades than did those of ovariectomised-implanted heifers. Fat thickness tended to be greater for autografted heifers than for heifers in the implant treatment groups (P <0.l0). Non-implanted autografted heifers had smaller ribeye areas, more kidney, pelvic and heart fat, and higher numerical USDA yield grades. Shear force values and taste panel scores for meat favoured non-implanted autografted heifers. In trial 2, 30 heifers were autografted, ovariectomised via high lumbar laparotomy, or left as intact controls. Heifers in trial 2 were fed a finishing diet until heifers reached 1.2 ern average backfat thickness. Intact heifers tended to gain weight more rapidly than did ovariectomised heifers. Ovarian cell types were detected at the graft sites of only four of the 10 autografted heifers upon post-mortem histological examination. Very low levels of oestrogen were present in the fluid aspirated from three of the apparently successful grafts. However, growth rate was not superior for these three heifers.     

The role of models in managing the uncertainty of software-intensive systems

It is increasingly argued that uncertainty is an inescapable feature of the design and operational behaviour of software-intensive systems. This paper elaborates the role of models in managing such uncertainty, in relation to evidence and claims for dependability. Personal and group models are considered with regard to abstraction, consensus and corroboration. The paper focuses on the predictive property of models, arguing for the need for empirical validation of their trustworthiness through experimentation and observation. The impact on trustworthiness of human fallibility, formality of expression and expressiveness is discussed. The paper identifies two criteria for deciding the degree of trust to be placed in a model, and hence also for choosing between models, namely accuracy and informativeness. Finally, analogy and reuse are proposed as the only means by which empirical evidence can be established for models in software engineering.     

The role of interior design elements in human responses to crowding.

The role of interior design elements in mitigating the negative relationship between residential crowding and psychological health was investigated. Residents of crowded homes with greater architectural depth (the number of spaces one must pass through to get from one room in the house to another) are less likely to socially withdraw or to be psychologically distressed than residents in crowded homes with relatively low depth. Additional analyses suggest that greater depth buffers the association between residential crowding and psychological distress because it reduces social withdrawal among residents of crowded homes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The microstructure and phase relationships in rapidly solidified type 304 stainless steel powders

The microstructure and relative amounts of fcc and bcc phases have been studied for rapidly solidified Type 304 stainless steel powders produced by vacuum gas atomization (VGA) and centrifugal atomization (CA). The VGA powder solidifies with a cellular microstructure while the CA powder has a dendritic microstructure. The volume fraction of fcc phase in the CA powder is found to increase from 40 Pct to 97 Pct with increasing particle size from 30 to 125 μm. In the VGA powder, the volume fraction of fcc phase is found to decrease from about 90 Pct to 77 Pct over the same range of particle sizes. The origins of the fcc and bcc phases in each powder are considered. It is concluded that bcc is present as both a primary crystallization phase in the smaller CA particles (<75 μm) and as compositionally stabilized eutectic ferrite at the cell walls of particles of both CA and VGA powders in which fcc was the primary crystallization phase.     

Exposure to hand-arm vibration: implications of new statutory requirements

One particular source of vibration exposure for manual workers results from using hand-held power tools. This is generally termed exposure to hand-arm vibration (HAV). Potential negative health effects from HAV were identified at the turn of the 20th century and have become more scientifically understood since then. Due to the nature of its activities, the construction industry is one industry sector representing significant HAV exposure risk. As of July 2005, the Control of Vibration at Work Regulations (CVWR) incorporate HAV into the UK workplace health and safety statute. Implications of the CVWR upon the construction sector are explored, particularly in the context of how construction activities may be affected by the new HAV exposure action and limit values. The paper also demonstrates potential 'problems' of considering (equipment) manufacturers' vibration data with those resulting from measurement of equipment at the workplace. It is concluded that due to limits on operator exposure times to higher vibration tools, the UK construction sector must ultimately come to terms with what will effectively represent an influential change in many of its on-site working practices.     

Overproduction and affinity purification of Saccharomyces cerevisiae replication factor C

Yeast replication factor C (RF-C) is a heteropentamer encoded by the RFC1-5 genes. RF-C activity in yeast extracts was overproduced about 80-fold after induction of a strain containing all five genes on a single plasmid, with expression of each gene placed under control of the galactose-inducible GAL1-10 promoter. This strongly indicates that overexpression of the five known RFC genes is sufficient for overproduction of RF-C. Overexpression of all five genes was also necessary to achieve overproduction of RF-C as omission of any single gene from the plasmid gave uninduced, i.e. normal cellular levels of RF-C. The interaction between RF-C and proliferating cell nuclear antigen (PCNA) was studied with PCNA-agarose beads. Binding of RF-C to PCNA-agarose beads is negligible in buffers containing 0.3 M NaCl. However, addition of Mg-ATP to the binding buffer caused strong binding of RF-C to the beads even at 0.8 M NaCl. Binding of ATP, but not its hydrolysis, was required for the strong binding mode as nonhydrolyzable analogs were also effective. The existence of two distinct binding modes between PCNA and RF-C was used as the key step in a greatly improved procedure for the purification of RF-C. RF-C from the overproduction strain purified by this procedure was essentially homogeneous and had a severalfold higher specific activity than RF-C preparations that had previously been purified through multicolumn procedures.     

Voice/Data Integration: Promise or Practice?

Voice/data integration has recently been the object of considerable attention. Although integration might result in operational improvements and reduced costs in some cases, these benefits cannot be guaranteed and will vary depending on the product and the organization that uses it.