1,466 research outputs found
The Practitioner\u27s Corner: An exploration of municipal active living charter development and advocacy
Background: Numerous municipal active living-‐related charters have been adopted to promote physical activity in Canada throughout the past decade. Despite this trend, there are few published critical examinations of the process through which charters are developed and used.
Purpose: Thus, the purpose of this study was to establish greater understanding of active living charter development and advocacy.
Methods: Semi-‐structured interviews were conducted with eight primary contributors to different active living-‐related charters across Ontario, Canada. Interview questions explored participants’ experiences developing and advocating for an active living charter. Interviews were analyzed using open, axial, and selective coding.
Results and Conclusions: Participants consistently described a process whereby an impetus triggered the development of a charter, which was subsequently adopted by regional or municipal council. Continued advocacy to develop awareness of the charter and to promote desired outcomes in the community was valued and the capacity of the working group as well as the local political context played pivotal roles in determining how the charter was implemented. Outcomes were, however, only objectively evaluated in one case that was described – evaluation being a process that many participants thought was omitted in regard to their own charter. This work provides practical guidance for health professionals developing regional active living charters as a component of broader advocacy efforts
Tree Growth and Cattle Weight Gain in a Ponderosa Pine System
Integrated timber and livestock systems (silvopastoral) are common in several regions of the United States. Grazing of three timber stands in eastern Nebraska showed no signs of tree damage due to rubbing or soil compaction. Steer gains were lower under the silvopastoral system compared to a typical pasture system (1.05 lb/day versus 1.70 lb/day). Growth of timber in silvopastoral stands was reduced (35.0 cubic feet per year versus 37.8 cubic feet per year); however, total productivity of the silvopastoral system (timber plus livestock) was greater ($20.98/acre) than with traditional timber systems
Impact of Cleaning Frequency on Nitrogen Balance in Open Feedlot Pens
Pen cleaning frequency of feedlot pens was evaluated during the summer of 2001 and 2002. Dry matter, organic matter and nitrogen recoveries were evaluated on a per head basis. Cleaning pens monthly compared to cleaning at the end of the feeding period resulted in significantly more DM, OM and N recovered. Cleaning pens every month increased N removal by 7.0 lb per steer (49.9% increase) above manure N removed at the end of the feeding period
Activity of the Bacillus anthracis 20 kDa protective antigen component
<p>Abstract</p> <p>Background</p> <p>Anthrax is caused by <it>Bacillus anthracis </it>that produce two exotoxins, lethal toxin and edema toxin. The lethal toxin is composed of the lethal factor (LF) complexed with the cell binding protective antigen (PA<sub>83</sub>, 83 kDa). Likewise, the edema factor (EF) binds to the PA<sub>83 </sub>to form the edema toxin. Once PA83 is bound to the host cell surface, a furin-like protease cleaves the full-length, inactive protein into 63 kDa and 20 kDa antigens (PA<sub>63 </sub>and PA<sub>20</sub>). PA<sub>63 </sub>forms a heptamer and is internalized via receptor mediated endocytosis forming a protease-stable pore, which allows EF and LF to enter the cell and exert their toxic effects.</p> <p>Both proteolytically cleaved protective antigens (PA<sub>63 </sub>and PA<sub>20 </sub>fragments) are found in the blood of infected animals. The 63 kDa protective antigen PA<sub>63 </sub>fragment has been thoroughly studied while little is known about the PA<sub>20</sub>.</p> <p>Methods</p> <p>In this study we examined the role of PA<sub>20 </sub>using high throughput gene expression analysis of human peripheral blood mononuclear cells (PBMC) exposed to the PA<sub>20</sub>. We constructed a PA mutant in which a Factor Xa proteolytic recognition site was genetically engineered into the protective antigen PA<sub>83 </sub>to obtain PA<sub>20 </sub>using limited digestion of this recombinant PA<sub>83 </sub>with trypsin.</p> <p>Results</p> <p>Global gene expression response studies indicated modulation of various immune functions and showed gene patterns indicative of apoptosis via the Fas pathway in a subset of the lymphoid cells. This finding was extended to include observations of increased Caspase-3 enzymatic activity and the identification of increases in the population of apoptotic, but not necrotic cells, based on differential staining methods. We identified a list of ~40 inflammatory mediators and heat-shock proteins that were altered similarly upon exposure of PBMC to either rPA<sub>20 </sub>or <it>B. anthracis </it>spores/vegetative cells.</p> <p>Conclusion</p> <p>This study shows that the PA<sub>20 </sub>has an effect on human peripheral blood leukocytes and can induce apoptosis in the absence of other PA components.</p
Undegradable Intake Protein Supplementation of Compensating Spring-Born Steers and Summer-Born Steers During Summer Grazing
Three trials were conducted to determine the effects of previous winter gain (Trials 1 and 3) and age of calf (Trials 1 and 2) on response to undegradable intake protein (UIP) supplementation during summer grazing. In Trial 1, 48 spring-born steers (243 kg) were used in a 4 &#;&#;2 factorial arrangement. Steers were wintered at four rates of gain: 0.65 (FAST), 0.24 (SLOW), 0.38 (S/F), and 0.38 (F/S) kg/d. The intermediate rates of gain (S/F and F/S) were created by switching steers from slow to fast or fast to slow midway through the wintering period. Following winter treatments, steers were assigned to one of two summer treatments: supplemented (S) or nonsupplemented (NS). In Trial 2, 32 summer-born steers were wintered at an ADG of 0.25 kg/d and allotted to the same summer treatments as Trial 1. The supplement was formulated to supply 200 g/d of UIP. Steers from both trials grazed upland Sandhills range from May to September 1998. In Trial 3, 49 spring-born steers (228 kg) were used in a 2 &#;&#;7 factorial arrangement of treatments. Steers were wintered at two rates of gain, 0.71 (FAST) and 0.24 kg/d (SLOW) and then assigned randomly to one of six levels of UIP supplementation or an energy control. Protein supplements were formulated to deliver 75, 112.5, 150, 187.5 225, or 262.5 g/d of UIP. Sources of UIP for all trials were treated soybean meal and feather meal. In Trial 1, there were no (P \u3e 0.05) winter by summer treatment interactions, and UIP supplementation increased (P = 0.0001) pasture gains over NS steers. In Trial 2, supplementation increased (P = 0.001) pasture ADG of summer-born steers by 0.15 kg/d compared with NS steers. In Trial 3, a winter gain by UIP supplementation interaction was observed (P = 0.09). Gain of FAST steers responded quadratically (P = 0.09) across UIP levels, with the maximum gain occurring at the 150 g/ d UIP level. The SLOW steers responded linearly (P = 0.02) to increasing UIP levels; however, the response was negative. Levels of UIP above 150 g/d reduced steers gains; therefore, the data were reanalyzed excluding these levels. These new analyses showed that FAST steers responded linearly (P = 0.08; 0.2 kg/d) to increasing UIP, whereas the SLOW steers had no response to UIP. In Trials 1 and 3, SLOW steers experienced compensatory gain and had higher gains overall. We concluded that previous winter gain affected the response to UIP supplementation with the FAST winter gain group having a greater response
Economic Analysis of Increased Corn Silage Inclusion in Beef Finishing Cattle
An economic analysis was conducted to assess the feasibility of feeding greater inclusions of corn silage in finishing diets. Cattle were fed two inclusions of corn silage (15 and 45% of diet dry matter) with or without tylosin. Cattle fed 15% corn silage with tylosin had the best feed conversion, 15 % corn silage without tylosin was intermediate, and both 45% corn silage with and without tylosin had the poorest feed conversion. Feeding corn silage at greater inclusions decreased ADG but increased final body weight when fed to an equal fatness (28 days longer). However, feeding corn silage at 45% was more economical compared to feeding 15% corn silage, especially at higher corn prices, provided shrink is well managed (less than 15%). Feeding elevated concentrations of corn silage may have an economic advantage while also offering the addition of liver abscess control in finishing diets without tylosin
A comparison of the galaxy populations in the Coma and distant clusters: the evolution of k+a galaxies and the role of the intracluster medium
The spectroscopic properties of galaxies in the Coma cluster are compared
with those of galaxies in rich clusters at , to investigate the
evolution of the star formation history in clusters. Luminous galaxies with
and post-starburst/post-starforming (k+a) spectra which
constitute a significant fraction of galaxies in distant cluster samples are
absent in Coma, where spectacular cases of k+a spectra are found instead at
and represent a significant proportion of the cluster dwarf galaxy
population. A simple inspection of their positions on the sky indicates that
this type of galaxy does not show a preferential location within the cluster,
but the bluest and strongest-lined group of k+a's lies in projection towards
the central 1.4 Mpc of Coma and have radial velocities significantly higher
than the cluster mean. We find a striking correlation between the positions of
these young and strong post-starburst galaxies and substructure in the hot
intracluster medium (ICM) identified from {\it XMM-Newton} data, with these
galaxies lying close to the edges of two infalling substructures. This result
strongly suggests that the interaction with the dense ICM could be responsible
for the quenching of the star formation (thus creating the k+a spectrum), and
possibly, for any previous starburst. The evolution with redshift of the
luminosity distribution of k+a galaxies can be explained by a ``downsizing
effect'', with the maximum luminosity/mass of actively star-forming galaxies
infalling onto clusters decreasing at lower redshift. We discuss the possible
physical origin of this downsizing effect and the implications of our results
for current scenarios of environmental effects on the star formation in
galaxies.Comment: 21 pages, 7 figures, to appear in ApJ, version after referee's
change
A Review of Corn Stalk Grazing on Animal Performance and Crop Yield
The highest cost to beef cow-calf and backgrounding operations is the feeding of stored feeds in winter months. Nebraska has an abundance of corn fields available for grazing following harvest. Utilization of corn crop residue is quite effective in reducing feed costs. There are a number of important considerations associated with residue utilization. Stocking rates, diet quality, genetically modified corn, subsequent crop yields and supplementation are discussed
A Review of Corn Stalk Grazing on Animal Performance and Crop Yield
The highest cost to beef cow-calf and backgrounding operations is the feeding of stored feeds in winter months. Nebraska has an abundance of corn fields available for grazing following harvest. Utilization of corn crop residue is quite effective in reducing feed costs. There are a number of important considerations associated with residue utilization. Stocking rates, diet quality, genetically modified corn, subsequent crop yields and supplementation are discussed
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