837 research outputs found

    On Biology and Technology: The Economics of Managing Biotechnologies

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    This paper considers those sectors of the economy that operate under the same regimes of rewarding private innovators as others, but differ in that they face recurring problems of resistance, as occur in the pharmaceutical and agricultural industries. This recurrence originates in the natural processes of selection and evolution among humanity’s biological competitors. The paper examines the capacity for decentralised patent-based incentive mechanisms to result in socially optimal outcomes in these sectors under scale- and speed-dependent evolution of pathogens. It demonstrates that there is a fundamental incompatibility between the dynamics of the patent system and the dynamics of the resistance problem under both types of evolution. Under scale-dependent evolution, the externalities within a patent-based system indicate that decentralised mechanisms will result in systematic underinvestment in R&D that decreases further with an increasing severity of the resistance problem. Under speed-dependent evolution, a patent-based system will fail to target socially optimal innovation size. The overall conclusion is that patent-based incentive mechanisms are incapable of sustaining society against a background of increasing resistance problems. The paper concludes with appropriate policy implications of these results.Biotechnology, R&D, Patents

    The Relationship Between Attitudes Towards Exercise and Endorphin Release on Cognitive Performance Following Treadmill Running

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    Exercise is cost-effective and reliably suggested to rescue cognitive decline in aging populations (Gomez-Pinilla & Hillman, 2013; Karssemeijer et al., 2017). In addition, exercise enhances cognitive functioning across the lifespan (Ellemberg & St. Louis-Deschenes, 2010; Jentsch & Wolf, 2020; Roig et al., 2013), however the specific mechanisms of exercise that enhance cognition are still unclear. Because exercise is linked with the brain’s opioid system (Farrell et al., 1982), the purpose of this project is to determine how the opioid system is activated by exercise to affect cognitive functioning. Additionally, we know that acute exercise enhances cognitive function and releases beta-endorphins, but we do not fully understand the effect that endorphin release after running has on cognitive function, nor what mediates endorphin release on an individual level. Thus, a major emphasis we are also investigating is attitudes towards running. We analyzed a university population (n=51) for cognitive performance and beta-endorphin concentration before and after running on a treadmill. To analyze cognitive performance, we utilized a Trail Making Test to measure executive function and a 2-back Task to measure working memory (Kirchner, 1958; Reitan, 1956). A short survey was used to assess participant’s attitudes towards running and running frequency (Ogden et al., 1997). Treadmill running was enacted to maintain a runner’s ideal running heart rate according to their age. Saliva taken before and after running was analyzed by Peninsula Labs immunoassay kit. To analyze the relationship between working memory, executive function, and endorphin release, a correlation was run. A correlation was also run for relationship between running attitudes, running frequency, and endorphin release. We expect there to be a negative correlation between working memory, executive function, and endorphin release as well as between running attitudes, running frequency, and endorphin release

    Concepts of Sliding and Lifting Tissue Movement in Flap Reconstruction

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94457/1/j.1524-4725.2000.09172.x.pd

    Prognostic Significance of Growth Kinetics in Newly Diagnosed Glioblastomas Revealed by Combining Serial Imaging with a Novel Biomathematical Model

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    Glioblastomas (GBMs) are the most aggressive primary brain tumors characterized by their rapid proliferation and diffuse infiltration of the brain tissue. Survival patterns in patients with GBM have been associated with a number of clinico-pathologic factors, including age and neurological status, yet a significant quantitative link to in vivo growth kinetics of each glioma has remained elusive. Exploiting a recently developed tool for quantifying glioma net proliferation and invasion rates in individual patients using routinely available magnetic resonance images (MRIs), we propose to link these patient-specific kinetic rates of biological aggressiveness to prognostic significance. Using our biologically-based mathematical model for glioma growth and invasion, examination of serial pre-treatment MRIs of 32 GBM patients allowed quantification of these rates for each patient’s tumor. Survival analyses revealed that even when controlling for standard clinical parameters (e.g., age, KPS) these model-defined parameters quantifying biologically aggressiveness (net proliferation and invasion rates) were significantly associated with prognosis. One hypothesis generated was that the ratio of the actual survival time after whatever therapies were employed to the duration of survival predicted (by the model) without any therapy would provide a “Therapeutic Response Index” (TRI) of the overall effectiveness of the therapies. The TRI may provided important information, not otherwise available, as to the effectiveness of the treatments in individual patients. To our knowledge, this is the first report indicating that dynamic insight from routinely obtained pre-treatment imaging may be quantitatively useful in characterizing survival of individual patients with GBM. Such a hybrid tool bridging mathematical modeling and clinical imaging may allow for statifying patients for clinical studies relative to their pretreatment biological aggressiveness

    Comparative evaluation of three egg production systems: Housing characteristics and management practices

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    This paper is an integral part of the special publication series that arose from the multidisciplinary and multi-institutional project of the Coalition for Sustainable Egg Supply (CSES). The CSES project involves 3 housing systems for egg production at the same research farm site in the Midwest, USA, namely, a conventional cage (CC) house, an aviary (AV) house, and an enriched colony (EC) house. The CC house (141.4 m L × 26.6 m W × 6.1 m H) had a nominal capacity of 200,000 hens (6 hens in a cage at a stocking density of 516 cm2/hen), and the cages were arranged in 10 rows, 8 tiers per cage row, with a perforated aisle walkway at 4-tier height. The AV house (154.2 m L × 21.3 m W × 3.0 m H) and the EC house (154.2 m L × 13.7 m W × 4.0 m H) each had a nominal capacity of 50,000 hens. The AV house had 6 rows of aviary colonies, and the EC house had 5 rows of 4-tier enriched colonies containing perches, nestbox, and scratch pads (60 hens per colony at a stocking density of 752 cm2/hen). The overarching goal of the CSES project, as stated in the opening article of this series, was to comprehensively evaluate the 3 egg production systems from the standpoints of animal behavior and well-being, environmental impact, egg safety and quality, food affordability, and worker health. So that all the area-specific papers would not have to repeat a detailed description of the production systems and the management practices, this paper is written to provide such a description and to be used as a common reference for the companion papers

    Cost–benefit analysis and efficient water allocation in Cyprus

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    The scarcity of water resources in both arid and temperate countries alike is one of the most pervasive natural resource allocation problems facing water users and policy-makers. In arid countries this problem is faced each day in the myriad of conflicts that surround its use.Water scarcity is a fact with which all countries have to become increasingly involved. Water scarcity occurs across many dimensions. First, there is growing demand for water in residential, industrial and agricultural sectors stemming largely from population and economic growth. Secondly, supply-side augmentation options have become increasingly constrained and restrictively costly in many countries. In combination, demand growth and supply-side interventions have stretched current water availability to its hydrological limits. In addition to these quantity constraints, the limits to the assimilative capacity of water resources for human and industrial waste have been reached in many places, and the quality of freshwater has been degraded (Winpenny, 1994)
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