Rapid Prototyping at Zero Gravity for In-Flight Repairs and Fabrication on Space Station Freedom

The ability to perform in-flight rapid prototyping would be of great benefit to NASA in two ways. First, repair parts could be fabricated from CAD designs beamed up from earth based laboratories which might allow a failed experiment to proceed. The mission specialists themselves, under the creative influence of space flight, might design a new part or tool and fabricate it on board in a matter of hours. Second, with metal casting and ceramic sintering facilities on board, rapid prototyping would allow manufacturing in space. This paper presents some test criteria for evaluating two of the rapid prototyping techniques, stereolithography and fused deposition, in microgravity conditions. Effects of the variation of head speed and strip width for the fused deposition process on the resulting mechanical properties are presented. The mechanical strength of the polyamide test bars increased with both increasing head speed and strip width. Increasing head speed would be desirable in microgravity applications.Mechanical Engineerin

TECHNICAL BARRIERS IN THE GLOBAL POULTRY MARKET: A SEARCH FOR 'MISSING TRADE'

This paper was presented at the INTERNATIONAL TRADE IN LIVESTOCK PRODUCTS SYMPOSIUM in Auckland, New Zealand, January 18-19, 2001. The Symposium was sponsored by: the International Agricultural Trade Research Consortium, the Venture Trust, Massey University, New Zealand, and the Centre for Applied Economics and Policy Studies, Massey University. Dietary changes, especially in developing countries, are driving a massive increase in demand for livestock products. The objective of this symposium was to examine the consequences of this phenomenon, which some have even called a "revolution." How are dietary patterns changing, and can increased demands for livestock products be satisfied from domestic resources? If so, at what cost? What will be the flow-on impacts, for example, in terms of increased demands for feedgrains and the pressures for change within marketing systems? A supply-side response has been the continued development of large-scale, urban-based industrial livestock production systems that in many cases give rise to environmental concerns. If additional imports seem required, where will they originate and what about food security in the importing regions? How might market access conditions be re-negotiated to make increased imports achievable? Other important issues discussed involved food safety, animal health and welfare and the adoption of biotechnology, and their interactions with the negotiation of reforms to domestic and trade policies. Individual papers from this conference are available on AgEcon Search. If you would like to see the complete agenda and set of papers from this conference, please visit the IATRC Symposium web page at: http://www1.umn.edu/iatrc.intro.htmInternational Relations/Trade,

A Framework for Analyzing Technical Trade Barriers in Agricultural Markets

Technical trade barriers are increasingly important in the international trade of agricultural products. Designing technical trade measures that can satisfy the growing demand for food safety, product differentiation, environmental amenities, and product information at the lowest cost to the consumer and to the international trading system requires an understanding of the complex economics of regulatory import barriers. This report proposes a definition and classification scheme to frame discussion and evaluation of such measures. Open-economy models that complement the classification scheme are developed graphically to highlight the basic elements that affect the economic impacts of changes in technical trade barriers.technical trade barriers, sanitary and phytosanitary, agricultural trade policy, environmental trade measures, International Relations/Trade,

FOOD REGULATION AND TRADE: TOWARD A SAFE AND OPEN GLOBAL SYSTEM -- AN OVERVIEW AND SYNOPSIS

A synopsis is presented of challenges faced and WTO performance in disciplining national technical measures to achieve legitimate objectives in a least-trade-distorting manner. Importance of the measures and international disciplines are reviewed and evidence presented from multiple perspectives that suggests a limited constructive WTO role.International Relations/Trade,

Mathematical structure of dual amplitudes

Firstly, the notion of duality is introduced and the generalized amplitude given in terms of the Koba - Nielsen variables. Furthermore, from the point of view of wave functions it is shown how the dynamical importance of spin implies an internal structure or extended description of hadrons which may be linked with duality (or internal symmetry),Then, in the following chapter, we first of all describe how certain mathematical characteristics emerge as being desirable for a strong interaction theory and indicate how these appear in various models, the relationships between which we also explain. It then appears that the most suitable language in which to discuss these properties is that of two-dimensional Riemann surfaces, which are most prominent in the Analogue Model. Chapter III indicates how the structure in dual models may be simply derived without an explicit physical interpretation (as in the functional integral formalism) - Ramond's Correspondence Principle. In the final chapter we propose an approach which embodies the surface description and the mathematical attributes mentioned above (without a tachyon). Furthermore, it amounts to an extended description of interacting hadrons, which, when reconciled with Poincare invariance, leads to the internal symmetry group of the original models

Moving beyond simple descriptive statistics in the analysis of online wildlife trade: an example from clustering and ordination

Collecting data for reports on online wildlife trade is resource-intensive and time-consuming. Learning often focuses on the main item traded by each country only. However, online trade is increasing, providing potential to update the conversation from a national scale to a global scale. We demonstrate how hierarchical clustering can identify wildlife items that follow similar trading patterns. We also ordinate the clusters, and seek correlations between the clusters and global measures, such as Worldwide Governance Indicators. We primarily use a sample dataset from a published report of online traded wildlife, covering 16 countries and 31 taxa or product types. Clustering provided immediate insights, such as rhinos and pangolins were traded similarly to ivory and suspected ivory. Five out of eight clusters represented items predominately traded by one country. An ordination of these clusters, and representation of global measures on the ordination axis, show a strong correlation of the ‘Voice and accountability' score with the clusters. Consequently, from the ‘Voice and accountability' score of the United States, a country not included in our dataset, we inferred that it traded elephant items (not ivory) and owl items during 2014

Kinematic dynamo action in a sphere. I. Effects of differential rotation and meridional circulation on solutions with axial dipole symmetry

A sphere containing electrically conducting fluid can generate a magnetic field by dynamo action, provided the flow is sufficiently complicated and vigorous. The dynamo mechanism is thought to sustain magnetic fields in planets and stars. The kinematic dynamo problem tests steady flows for magnetic instability, but rather few dynamos have been found so far because of severe numerical difficulties. Dynamo action might, therefore, be quite unusual, at least for large-scale steady flows. We address this question by testing a two-parameter class of flows for dynamo generation of magnetic fields containing an axial dipole. The class of flows includes two completely different types of known dynamos, one dominated by differential rotation (D) and one with none. We find that 36% of the flows in seven distinct zones in parameter space act as dynamos, while the remaining 64% either fail to generate this type of magnetic field or generate fields that are too small in scale to be resolved by our numerical method. The two previously known dynamo types lie in the same zone, and it is therefore possible to change the flow continuously from one to the other without losing dynamo action. Differential rotation is found to promote large-scale axisymmetric toroidal magnetic fields, while meridional circulation (M) promotes large-scale axisymmetric poloidal fields concentrated at high latitudes near the axis. Magnetic fields resembling that of the Earth are generated by D > 0, corresponding to westward flow at the surface, and M of either sign but not zero. Very few oscillatory solutions are found

Stair-case in the north trancept, Cathedral of Burgos [Material gráfico]

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

Effects of Home-Based Exercise Training Systems, Combined with Diet, on Cardiometabolic Health

International Journal of Exercise Science 12(2): 871-885, 2019. The efficacy of exercise training systems designed to be used in the home on cardiometabolic outcomes remains largely unknown. This investigation included two studies. Study 1 tested the effects a multi-exercise pulley system(NordicTrack Fusion CST with video trainer) and Study 2 an incline trainer (NordicTrack X22i with video trainer), both combined with daily food provision, for 12-weeks on indices of cardiometabolic health. Study 1 enrolled 27 adults (11 men, 16 women, 33.8±4.4 years of age) and Study 2 enrolled 29 adults (11 men, 18 women, 40.8±12.5 years of age). Pre- and post-intervention measurements were performed for body weight, fat mass, lean tissue mass, and visceral fat by dual energy x-ray absorptiometry, blood pressure, aerobic fitness and body circumferences. For Study 1, there were significant decreases in body weight, fat mass, visceral fat, diastolic blood pressure (DBP), resting heart rate (RHR), and all circumference sites, while there was an increase in aerobic fitness (all p\u3c0.001). Both males and females exhibited significant improvement in all these outcomes. For Study 2, there were significant decreases in body weight, fat mass, visceral fat, DBP, RHR, all circumference sites (all p\u3c0.001), and lean tissue mass (LTM) (p=0.006), and an increase in aerobic fitness (p\u3c0.001). Both males and females exhibited significant changes in all these outcomes, except LTM which did not change in females. Both studies exhibited high exercise session attendance and high dietary adherence. Overall these data indicate the potential efficacy of home-based training systems, when combined with diet, on selected cardiometabolic outcomes

History of the Innovation of Damage Control for Management of Trauma Patients: 1902-2016

Objective: To review the history of the innovation of damage control (DC) for management of trauma patients. Background: DC is an important development in trauma care that provides a valuable case study in surgical innovation. Methods: We searched bibliographic databases (1950-2015), conference abstracts (2009-2013), Web sites, textbooks, and bibliographies for articles relating to trauma DC. The innovation of DC was then classified according to the Innovation, Development, Exploration, Assessment, and Long-term study model of surgical innovation. Results: The innovation\u27\u27 of DC originated from the use of therapeutic liver packing, a practice that had previously been abandoned after World War II because of adverse events. It then developed\u27\u27 into abbreviated laparotomy using rapid conservative operative techniques.\u27\u27 Subsequent exploration\u27\u27 resulted in the application of DC to increasingly complex abdominal injuries and thoracic, peripheral vascular, and orthopedic injuries. Increasing use of DC laparotomy was followed by growing reports of postinjury abdominal compartment syndrome and prophylactic use of the open abdomen to prevent intra-abdominal hypertension after DC laparotomy. By the year 2000, DC surgery had been widely adopted and was recommended for use in surgical journals, textbooks, and teaching courses ( assessment\u27\u27 stage of innovation). Long-term study\u27\u27 of DC is raising questions about whether the procedure should be used more selectively in the context of improving resuscitation practices. Conclusions: The history of the innovation of DC illustrates how a previously abandoned surgical technique was adapted and readopted in response to an increased understanding of trauma patient physiology and changing injury patterns and trauma resuscitation practices