2,805 research outputs found
An Analysis of the Competitive Position of Cattle Finishing in Utah and Selected Western States, 1969
Utah\u27s cattle feeding industry was described by using both secondary and primary data. The primary data were collected through use of a personal interview survey.
Primary data were also collected in Idaho, while secondary data were used for Arizona, California and Colorado.
Intrastate analysis of feeding costs showed definite cost savings were achieved in all states through economies of size.
Interstate analysis of feeding costs showed Utah\u27s larger capacity feedlots to be very competitive with larger capacity lots in other states.
1968 prices for both slaughter and feeder cattle were computed for each state. Prices in Utah were slightly lower for both slaughter and feeder cattle than other states.
A comparison of net return per unit fed in large feedlots indicated Utah\u27s larger feedlots were competitive with feedlots in other states
The Z Charmoniumlike Mesons
A brief review of the experimental situation concerning the
electrically-charged charmoniumlike meson candidates, , is presented
The influence of tropospheric biennial oscillation on mid-tropospheric CO_2
Mid-tropospheric CO_2 retrieved from the Atmospheric Infrared Sounder (AIRS) was used to investigate CO_2 interannual variability over the Indo-Pacific region. A signal with periodicity around two years was found for the AIRS mid-tropospheric CO_2 for the first time, which is related to the Tropospheric Biennial Oscillation (TBO) associated with the strength of the monsoon. During a strong (weak) monsoon year, the Western Walker Circulation is strong (weak), resulting in enhanced (diminished) CO_2 transport from the surface to the mid-troposphere. As a result, there are positive (negative) CO2 anomalies at mid-troposphere over the Indo-Pacific region. We simulated the influence of the TBO on the mid-tropospheric CO_2 over the Indo-Pacific region using the MOZART-2 model, and results were consistent with observations, although we found the TBO signal in the model CO_2 is to be smaller than that in the AIRS observations
Cu-Enhanced 3-D Printed Fuels for Green SmallSat Propulsion
The Propulsion Research Laboratory at Utah State University (USU) has recently developed a promising High-Performance Green Hybrid Propulsion (HPGHP) technology that derives from the novel electrical breakdown property of certain 3-D printed like acrylonitrile butadiene styrene (ABS). This electrical breakdown property has been engineered into a proprietary, power-efficient system that can be cold-started and restarted with a high degree of reliability. One of the issues associated with ABS as a propellant is its low burn rate. It is well documented in technical literature that hybrid rocket systems generally have fuel regression rates that are typically 25-30% lower than solid fuel motors in the same thrust and impulse class. Lowered fuel regression rates tend to produce unacceptably low equivalence ratios that lead to poor mass-impulse performance, erosive fuel burning, nozzle erosion, reduced motor duty cycles, and the potential for combustion instability. To achieve equivalence ratios that produce acceptable combustion characteristics, hybrid fuel ports are often fabricated with large length-to-diameter ratios. The resulting poor volumetric efficiency is incompatible with Small Satellite (SmallSat) applications.
This paper presents preliminary results from a collaborative development program between the University of Miami (UM) and USU. In this reported work, modern extrusion and 3-D printing techniques are used to fabricate sample ABS fuel grains with varying levels of copper-metallization. Hybrid-ABS fuel grains were printed from Cu-infused feed stock with 2%, 4%, and 6% Cu-mass concentrations. As baseline control, 100% pure ABS fuel grains (0% Cu) were also printed. Heat conduction via the additive copper (Cu) provides an efficient heat transfer mechanism that augments surface convection from the flame zone. Forced convection, the primary mechanism for pyrolysis for hybrid fuels, is generally inefficient due to wall-blowing associated with the radially emanating mass flow from fuel pyrolysis. Wall-blowing pushes the flame zone away from the fuel surface and significantly reduces the rate of enthalpy exchange. Homogeneously mixing a high conductivity metal such as Cu into the ABS fuel provides an efficient heat transfer mechanism, and allows radiant heat from the flame zone to be transferred deep into the fuel material. This process significantly increases the pyrolytic efficiency of the fuels.
The Cu-infused fuels were tested at USU using a legacy 12-N hybrid thruster system. Fabrication and manufacturing methods are described, and results of hot fire tests are presented. The top-level conclusion is that Cu-infusion of the printed fuels measurably increases the fuel regression rate, allowing for a higher thrust level with no increase in the required volume. The Cu-infusion has negligible impact on the propellant characteristic velocity and the overall system specific impulse. The increased burn rate and overall increase in solid-fuel density resulting from Cu-infusion allows a measurable increase in the propellant impulse-density. This increase in volumetric efficiency is potentially significant for small spacecraft applications where available space has a premium value. Follow-on methods that infuse lower-molecular weight and higher thermal conductivity materials like graphene and carbon-nanotubes are proposed
The Exotic XYZ Charmonium-like Mesons
Charmonium, the spectroscopy of c\bar{c} mesons, has recently enjoyed a
renaissance with the discovery of several missing states and a number of
unexpected charmonium-like resonances. The discovery of these new states has
been made possible by the extremely large data samples made available by the
B-factories at the Stanford Linear Accelerator Center and at KEK in Japan, and
at the CESR e^+e^- collider at Cornell. Conventional c\bar{c} states are well
described by quark potential models. However, many of these newly discovered
charmonium-like mesons do not seem to fit into the conventional c\bar{c}
spectrum. There is growing evidence that at least some of these new states are
exotic, i.e. new forms of hadronic matter such as mesonic-molecules,
tetraquarks, and/or hybrid mesons. In this review we describe expectations for
the properties of conventional charmonium states and the predictions for
molecules, tetraquarks and hybrids and the various processes that can be used
to produce them. We examine the evidence for the new candidate exotic mesons,
possible explanations, and experimental measurements that might shed further
light on the nature these states.Comment: 28 pages, 7 figures. Review for Ann Rev Nucl & Part Sc
Beliefs, barriers, and promotion practices of Indian nurses' regarding healthy eating for cancer survivors in a tertiary care hospital-A cross sectional survey
PURPOSE: To describe the beliefs, barriers and promotion practices of Indian nurses' regarding healthy eating (HE) behaviours amongst cancer survivors, and to gain insights into whether their educational qualifications might affect the promotion of HE.METHODS: Data was gathered using a validated questionnaire, 388 of the approached 400 nurses who worked at a tertiary care hospital in India gave informed consent to participate in the study. The Mann-Whitney U test and the Chi square analysis (for continuous and categorical variables respectively) were performed to carry out sub-group comparisons based on the qualification of the nurses i.e., Bachelor of Science in Nursing (BSc) and General Nursing and Midwifery (GNM).RESULTS: The nurses believed that dieticians/nutritionists were primarily responsible for educating the cancer survivors regarding HE. HE was promoted by nurses' relatively equally across multiple treatment stages ("during" treatment 24.4%, "post" treatment 23.1%; and "pre" treatment 22.3%). Nurses' believed HE practices had numerous benefits, with improved health-related quality of life (HRQoL) (75.7%), and mental health (73.9%) being the most frequent responses. The most frequently cited barriers by the nurses in promoting HE were lack of time (22.2%), and lack of adequate support structure (19.9%). Sub-group comparisons generally revealed no significant difference between the BSc and GNM nurses in their perceptions regarding HE promotion to cancer survivors. Exceptions were how the GNM group had significantly greater beliefs regarding whether HE can "reduce risk of cancer occurrence" ( p = 0.004) and "whether or not I promote HE is entirely up to me" ( p = 0.002). CONCLUSION: The nurses in India believe in the promotion of HE practices among cancer survivors across various stages of cancer treatments. However, they do face a range of barriers in their attempt to promote HE. Overcoming these barriers might facilitate effective promotion of HE among cancer survivors and help improve survivorship outcomes.IMPLICATIONS FOR CANCER SURVIVORS: Indian nurses employed in the two tertiary care hospitals wish to promote HE among cancer survivors, but require further knowledge and support services for more effective promotion of HE.</p
- …