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Interdomain competition: Arabidopsis thaliana versus Soil Bacteria
No full textPlants in their natural habits are constantly competing with other organisms.Arabidopsis thaliana is a model plant that must germinate and grow in the presence ofcommon soil bacteria such as Pseudomonas aeruginosa and Bacillus subtilis. A.thalianamay compete with soil bacteria such as for water, micronutrients, and the carbohydrate produced by photosynthesis. If there is competition between plants and soil bacteria, conditions that favor the growth of microorganisms will negatively impact plant development.A. thaliana was grown in petri dishes inoculated with Pseudomonas aeruginosa and Bacillus subtilis. Murashige and Skoog agar, a plant growth media, was used initially, to favor plant growth. The experiment was done in both warm conditions, that favor bacteria, and cool conditions, that discourage bacterial growth, and at high and low concentrations of bacteria. Later in the experiment, the growth of P. aureginosa and B. subtilis was enhanced by adding nutrient broth to the petri dishes. We found that, under these conditions, the plants are only vulnerable to bacterial competition at the earliest stages, and only with low concentration of B. subtilis under warm conditions. Bacterial growth later in plant development actually seems to promote plant growth
Mean Reversion of Oil Prices
No full textManaging natural resource projects requires that future costs and revenues be forecasted. Most commodity pricing models are fairly simple, involving a slow, steady increase in base prices while including volatility. When analyzing stock prices, this pattern is commonly referred to as the 'random walk'. Complicating the forecasting process is the fact that many commodities exhibit mean reverting tendencies, where prices may increase or decrease, but tend to revert to a long-term mean. Stock price volatility is measured using the standard deviation of the rate of return of a stock. Commodity price volatility is the same; however, when mean reversion exists, the normal standard deviation will overestimate true volatility. This complicates the pricing of many types of derivatives that are based on commodity prices. This work investigates the mean reversion tendency of oil prices. Specifically , a 25 year database of West Texas Intermediate daily oil prices is analyzed to determine price volatility, mean reversion speed, and the adjusted volatility that should be applied to today's oil-related projects
Manipulative Therapy for Lower Extremity Conditions: Update of a Literature Review
No full textObjective - The purpose of this study is to update a systematic review on manipulative therapy (MT) for lower extremity conditions. Methods - A review of literature was conducted using MEDLINE, MANTIS, Science Direct, Index to Chiropractic Literature, and PEDro from March 2008 to May 2011. Inclusion criteria required peripheral diagnosis and MT with or without adjunctive care. Clinical trials were assessed for quality using a modified Scottish Intercollegiate Guidelines Network (SIGN) ranking system. Results - In addition to the citations used in a 2009 systematic review, an additional 399 new citations were accessed: 175 citations in Medline, 30 citations in MANTIS, 98 through Science Direct, 54 from Index to Chiropractic Literature, and 42 from the PEDro database. Forty-eight clinical trials were assessed for quality. Conclusions - Regarding MT for common lower extremity disorders, there is a level of B (fair evidence) for short-term and C (limited evidence) for long-term treatment of hip osteoarthritis. There is a level of B for short-term and C for long-term treatment of knee osteoarthritis, patellofemoral pain syndrome, and ankle inversion sprain. There is a level of B for short-term treatment of plantar fasciitis but C for short-term treatment of metatarsalgia and hallux limitus/rigidus and for loss of foot and/or ankle proprioception and balance. Finally, there is a level of I (insufficient evidence) for treatment of hallux abducto valgus. Further research is needed on MT as a treatment of lower extremity conditions, specifically larger trials with improved methodology.http://dx.doi.org/10.1016/j.jmpt.2012.01.00
More Reliable Cloud Systems- A System Accounting Approach
Get PDFCloud computing has attracted more and more attention and has been used in more and more applications in many different fields. As we know, cloud computing delivers computing as a service. Its adoption widely depends upon the reliability of its systems. However, self-monitoring and adaptation are overlooked by most system designers and architects. Extant system accounting functionalities mainly focus on recent error causes, which is insufficient for long-term history analysis and event prediction. Our approach not only analyzes system events from both service consumers and providers, but also provides a layered composable system accounting framework in cloud computing environments. By self-monitoring, history analysis, event prediction and recovery, a new refined quality of reliability (QoR) for cloud computing is essentially provided. An implementation of this framework in an education services environment confirms the advantages over extant system accounting systems
Transformational Leadership Characteristics of College and University Presidents of Private Title III and Title V-Eligible Institutions
No full textThe purpose of this descriptive, quantitative study was to investigate the transformational leadership characteristics of college and university presidents of Title III and Title V-eligible institutions. Private institutions of higher education comprise approximately half of the total postsecondary institutions in the U.S. However, they are at greater risk for closure than their public counterparts. The U.S. Department of Education's Strengthening Institutions Program, also known as Title III, was created as part of the Higher Education Act of 1965 to provide competitive grant support to institutions with higher percentages of low-income students and comparatively smaller general and educational expenditures per student. These institutions were considered vulnerable and at the same time, deemed to be important for the nation's growing number of college-bound students. The Hispanic-Serving Institutions Program, also known as Title V, was established a few decades later to serve institutions with a significant percentage of Hispanic students in addition to the Title III institutional characteristics. Higher education leadership theorists vary in their views on the efficacy of president transformational leadership in the college and university setting. However, by nature, private Title III and V-eligible institutions are at some risk for survival and president transformational leadership practices could provide the leverage needed for continued existence and prosperity. The 219 Private, four -year Title III and V-eligible college and university presidents were invited to complete Kouzes and Posner's Leadership Practices Inventory-Self (LPI) in order to measure their leader behaviors through the LPI descriptors, "Model the Way," "Inspire a Shared Vision," "Challenge the Process," "Enable Others to Act," and "Encourage the Heart." President and institutional demographic information was also collected on gender, race/ethnicity, number of years in current position, total undergraduate student population, percent undergraduate minority population, urban or non-urban campus setting, and institutional religious affiliation to analyze for potential relationships and differences in LPI-descriptor responses. The data-generating sample was comprised of 146 presidents (66.67%) of private, four-year Title III and Veligible institutions located throughout the United States. Presidents reported levels of engagement in transformational leader behaviors that were higher than a national average of executive managers, as measured by the Leadership Practices Inventory (LPI) (Posner, 2009). The presidents' strongest transformational leader behavior was reported as "Enable Others to Act," followed by "Model the Way," "Inspire a Shared Vision," "Encourage the Heart," and "Challenge the Process." Undergraduate enrollment was the only variable in the study that demonstrated significance with regards to the LPI descriptor scores. The relationship between enrollment and president responses to three of the five LPI descriptors approached significance. Undergraduate enrollment approached significance as a predictor variable in a multiple regression of institutional characteristics for two LPI descriptors and was a significant positive predictor for the leader behavior,"Challenge the Process.
Characterization of Fuel Cell System
No full textFuel cell has been regarded as a promising technology for its use in renewable energy applications. This poster is focused on the characterization of a H2 PEM fuel cell stack and the interpretation of the experimental results
Searching for Key Success Factors of Ubiquitous Supply Chain Management from Dual Perspectives
No full textThere has been a little research focusing on the relationship between the key success factors and the benefits of ubiquitous supply chain management (USCM) adoption. Relying on the literature review, case analysis and interview, this research identified the key success factors and the benefits associated to the adoption of USCM. Upon collecting survey data, this research carried out an empirical examination for the relationship between key success factors and USCM adoption benefits. The results revealed that some factors in the management and technical aspects were closely associated with the benefits of USCM adoption. These findings bring us to an USCM adoption model. The current study is significant in that it provides empirical and theoretical insights for future researches and a practical guideline taking into account the adoption of USCM and ubiquitous computing
Implementation of Fault Tolerance Algorithm to Restore Affected Nodes in Scheduling Clusters
No full textDue to the convergence of the networks, the top priority objective of researchers is to get the network fully connected. Several types of networks have been introduced and proposed to improve performance. Cluster environment provides full support for various applications. Scheduling is one of the most important research-focusing areas, where different supporting algorithms are implemented. However, there is still a gap in scheduling to provide best network connectivity to all nodes. This paper targets nodes affected issue that occurs due to scalability, data sharing, while leaving and joining the nodes. To control and retain an affected node in the clustering scheduling, fault tolerance techniques are applied. The base of this technique is Node Recovery Algorithm (NRA). This algorithm supports disconnected nodes and restores them to join the scheduling. Furthermore, this algorithm maximizes the efficiency of the cluster and improves the performance