B746: Economies of Size for Maine Potato Packing Plants

The objective of this study was to find where economies in scale lie, and what, if any, would be the preferred or most economical in packing facilities. Data relative to equipment and labor requirements and capabilities and to materials and services were obtained through manufacturers, sales agencies, research studies and case studies. Two computerized programs were developed to select equipment, labor, and facilities which would be most efficient and least-cost and this was done for packing 10-pound bags with potatoes. Ten model lines resulted from the analysis allowing for input rates of 80 to 800 cwt/hr when based on a particular set of variables established as standard . Among the standard variables were 180 working days of 9 hours each, with the equipment operating 80% of the time handling an input flow of potatoes from which 10 percent were removed as undersized and 10 percent were removed as grade defective.https://digitalcommons.library.umaine.edu/aes_bulletin/1098/thumbnail.jp

B798: A Census of Maine\u27s Potato Production, Storage, and Packing Operation

Both internal and external factors relating to the production and marketing of Maine potatoes continue to influence and often undermine the profitability and market position of this important agricultural industry in the State. Among these factors are the technical aspects related to commercial production, storage and packing of potatoes in Maine; the current market structure; responses by the Maine industry to market preferences; and public policies, both foreign and domestic, affecting financial conditions and promotional activities in Maine and competing production regions. The quality of Maine potatoes in produce outlets in major Eastern U.S. markets is affected by production practices, handling methods, storage conditions, and quality maintenance and control practices. The organizational aspects of the marketing system at least partially determine the level of success in overall product marketing including the accurate and timely transmission of market information. Successful marketing also depends on the ability arid willingness of the industry to make use of such information in developing and implementing future marketing plans. Credit availability and policies in Maine and other regions are increasingly important as profit margins are reduced in times of low market prices and increasing production costs for all producers. In order to expand market demand for its product, industry promotional expenditures and activities may be inadequate.https://digitalcommons.library.umaine.edu/aes_bulletin/1115/thumbnail.jp

Interferometry

The following recommended programs are reviewed: (1) infrared and optical interferometry (a ground-based and space programs); (2) compensation for the atmosphere with adaptive optics (a program for development and implementation of adaptive optics); and (3) gravitational waves (high frequency gravitational wave sources (LIGO), low frequency gravitational wave sources (LAGOS), a gravitational wave observatory program, laser gravitational wave observatory in space, and technology development during the 1990's). Prospects for international collaboration and related issues are also discussed

Long-lived space observatories for astronomy and astrophysics

NASA's plan to build and launch a fleet of long-lived space observatories that include the Hubble Space Telescope (HST), the Gamma Ray Observatory (GRO), the Advanced X Ray Astrophysics Observatory (AXAF), and the Space Infrared Telescope Facility (SIRTF) are discussed. These facilities are expected to have a profound impact on the sciences of astronomy and astrophysics. The long-lived observatories will provide new insights about astronomical and astrophysical problems that range from the presence of planets orbiting nearby stars to the large-scale distribution and evolution of matter in the universe. An important concern to NASA and the scientific community is the operation and maintenance cost of the four observatories described above. The HST cost about $1.3 billion (1984 dollars) to build and is estimated to require$160 million (1986 dollars) a year to operate and maintain. If HST is operated for 20 years, the accumulated costs will be considerably more than those required for its construction. Therefore, it is essential to plan carefully for observatory operations and maintenance before a long-lived facility is constructed. The primary goal of this report is to help NASA develop guidelines for the operations and management of these future observatories so as to achieve the best possible scientific results for the resources available. Eight recommendations are given

Probing the structure of the cold dark matter halo with ancient mica

Mica can store (for >1 Gy) etchable tracks caused by atoms recoiling from WIMPs. Ancient mica is a directional detector despite the complex motions it makes with respect to the WIMP "wind". We can exploit the properties of directionality and long integration time to probe for structure in the dark matter halo of our galaxy. We compute a sample of possible signals in mica for a plausible model of halo structure.Comment: 7 pages, 2 figure

Kerr-Newman Black Hole Thermodynamical State Space: Blockwise Coordinates

A coordinate system that blockwise-simplifies the Kerr-Newman black hole's thermodynamical state space Ruppeiner metric geometry is constructed, with discussion of the limiting cases corresponding to simpler black holes. It is deduced that one of the three conformal Killing vectors of the Reissner-Nordstrom and Kerr cases (whose thermodynamical state space metrics are 2 by 2 and conformally flat) survives generalization to the Kerr-Newman case's 3 by 3 thermodynamical state space metric.Comment: 4 pages incl 2 figs. Accepted by Gen. Rel. Grav. Replaced with Accepted version (minor corrections

Outcomes of less invasive J-incision approach to aortic valve surgery

ObjectiveLess invasive approaches to aortic valve surgery are increasingly used; however, few studies have investigated their impact on outcome. We sought to compare clinical outcomes after these approaches with full sternotomy using propensity-matching methods.MethodsFrom January 1995 to January 2004, a total of 2689 patients underwent isolated aortic valve surgery, 1193 via upper J-hemisternotomy and 1496 via full sternotomy. Because of important differences in patient characteristics between these groups, a propensity score based on 42 variables was used to obtain 832 well-matched patient pairs (70% of possible cases).ResultsIn-hospital mortality was identical for propensity-matched patients, 0.96% (8 in each). Occurrences of stroke (P > .9), renal failure (P = .8), and myocardial infarction (P = .7) were similar. However, 24-hour mediastinal drainage was a third less after less invasive surgery (median, 250 vs 350 mL; P < .0001), and fewer patients received transfusions (24% vs 34%; P < .0001). More patients undergoing less invasive surgery were extubated in the operating room (12% vs 1.6%; P < .0001), postoperative forced 1-second expiratory volume was higher (P = .009), and fewer had respiratory failure (P = .01). Early after operation, pain scores were lower (P < .0001) after less-invasive surgery and postoperative length of stay shorter (P < .0001).ConclusionsWithin that portion of the spectrum of isolated aortic valve surgery where propensity matching was possible, minimally invasive aortic valve surgery had not only cosmetic advantages, but blood product use, respiratory, pain, and resource utilization advantages over full sternotomy, and no apparent detriments. Less invasive aortic valve surgery should be considered for most aortic valve operations

The Case for Dynamic Models of Learners' Ontologies in Physics

In a series of well-known papers, Chi and Slotta (Chi, 1992; Chi & Slotta, 1993; Chi, Slotta & de Leeuw, 1994; Slotta, Chi & Joram, 1995; Chi, 2005; Slotta & Chi, 2006) have contended that a reason for students' difficulties in learning physics is that they think about concepts as things rather than as processes, and that there is a significant barrier between these two ontological categories. We contest this view, arguing that expert and novice reasoning often and productively traverses ontological categories. We cite examples from everyday, classroom, and professional contexts to illustrate this. We agree with Chi and Slotta that instruction should attend to learners' ontologies; but we find these ontologies are better understood as dynamic and context-dependent, rather than as static constraints. To promote one ontological description in physics instruction, as suggested by Slotta and Chi, could undermine novices' access to productive cognitive resources they bring to their studies and inhibit their transition to the dynamic ontological flexibility required of experts.Comment: The Journal of the Learning Sciences (In Press

Radiation therapy generates platelet-activating factor agonists

Pro-oxidative stressors can suppress host immunity due to their ability to generate oxidized lipid agonists of the platelet-activating factor-receptor (PAF-R). As radiation therapy also induces reactive oxygen species, the present studies were designed to define whether ionizing radiation could generate PAF-R agonists and if these lipids could subvert host immunity. We demonstrate that radiation exposure of multiple tumor cell lines in-vitro, tumors in-vivo, and human subjects undergoing radiation therapy for skin tumors all generate PAF-R agonists. Structural characterization of radiation-induced PAF-R agonistic activity revealed PAF and multiple oxidized glycerophosphocholines that are produced non-enzymatically. In a murine melanoma tumor model, irradiation of one tumor augmented the growth of the other (non-treated) tumor in a PAF-R-dependent process blocked by a cyclooxygenase-2 inhibitor. These results indicate a novel pathway by which PAF-R agonists produced as a byproduct of radiation therapy could result in tumor treatment failure, and offer important insights into potential therapeutic strategies that could improve the overall antitumor effectiveness of radiation therapy regimens

15th Annual Seminar on Estate Planning

Outlines of speakers\u27 presentations from the 15th Annual Seminar on Estate Planning held by UK/CLE on July 15-16, 1988