58 research outputs found
Estimation of the Optimal Statistical Quality Control Sampling Time Intervals Using a Residual Risk Measure
Background: An open problem in clinical chemistry is the estimation of the optimal sampling time intervals for the application of statistical quality control (QC) procedures that are based on the measurement of control materials. This is a probabilistic risk assessment problem that requires reliability analysis of the analytical system, and the estimation of the risk caused by the measurement error. Methodology/Principal Findings: Assuming that the states of the analytical system are the reliability state, the maintenance state, the critical-failure modes and their combinations, we can define risk functions based on the mean time of the states, their measurement error and the medically acceptable measurement error. Consequently, a residual risk measure rr can be defined for each sampling time interval. The rr depends on the state probability vectors of the analytical system, the state transition probability matrices before and after each application of the QC procedure and the state mean time matrices. As optimal sampling time intervals can be defined those minimizing a QC related cost measure while the rr is acceptable. I developed an algorithm that estimates the rr for any QC sampling time interval of a QC procedure applied to analytical systems with an arbitrary number of critical-failure modes, assuming any failure time and measurement error probability density function for each mode. Furthermore, given the acceptable rr, it can estimate the optimal QC sampling time intervals
Comparative LCA technology improvement opportunities for a 1.5 MW wind turbine in the context of an offshore wind farm
Wind energy is playing an increasingly important role in the development of cleaner and more efficient energy technologies leading to projections in reliability and performance of future wind turbine designs. This paper presents life cycle assessment (LCA) results of design variations for a 1.5 MW wind turbine due to the potential for advances in technology to improve the performance of a 1.5 MW wind turbine. Five LCAs have been conducted for design variants of a 1.5 MW wind turbine. The objective is to evaluate potential environmental impacts per kilowatt hour of electricity generated for a 114 MW onshore wind farm. Results for the baseline turbine show that higher contributions to impacts were obtained in the categories Ozone Depletion Potential, Marine Aquatic Eco-toxicity Potential, Human Toxicity Potential and Terrestrial Eco-toxicity Potential compared to Technology Improvement Opportunities (TIOs) 1 to 4. Compared to the baseline turbine, TIO 1 showed increased impact contributions to Abiotic Depletion Potential, Acidification Potential, Eutrophication Potential, Global Warming Potential and Photochemical Ozone Creation Potential, and TIO 2 showed an increase in contributions to Abiotic Depletion Potential, Acidification Potential and Global Warming Potential. Additionally, lower contributions to all the environmental categories were observed for TIO 3 while increased contributions towards Abiotic Depletion Potential and Global Warming Potential were noted for TIO 4. A comparative LCA study of wind turbine design variations for a particular power rating has not been explored in the literature. This study presents new insight into the environmental implications related with projected wind turbine design advancements
Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine
[This corrects the article DOI: 10.1186/s13054-016-1208-6.]
On the Determinants of Social Capital in Greece Compared to Countries of the European Union
Functions of reuse and recycling in the service economy
The present paper aims at communicating the business world the vision of sustainable competitiveness entailing the adoption of the new business models of producing, selling and maintaining performance over time. These models include strategies that can head firms in designing and producing goods that facilitate the efficient use of resources throughout their entire life cycle including the end-of-life phase. A description of the industrial and service economy highlight that a transition towards the functional service economy requires a shift to a recycling society, where waste is considered and used as a resource. The closure of loops is represented by closed-loop supply chains and a sustainable product-life cycle leading to the products\u92 second life, where various rules, business strategies and scientific and engineering instruments are applied. Reuse and recycling are basic strategies incorporated in the sustainable product-life cycle and their applications and implications in the service economy are thoroughly investigated. The findings conclude that for the extension of products\u92 service-life all parties of the entire supply chain need to cooperate in an environment characterized of reduced resource throughput, minimized waste generation, access to information and optimized infrastructure. In this framework, the paper concludes with a suggestion of a synergy of proactive Small and Medium Enterprises (SME\u92s) coexisting in Eco-Industrial Parks for the advancement of their CLSC capabilities. This research enlightens firms about the key corporate strategies of the functional service economy and the business practices and tools that optimize quality and performance while maximizing profits and minimizing the environmental footprint
We are what we eat: Ubiquitin–proteasome system (UPS) modulation through dietary products
During lifetime, the molecular mechanisms that are responsible for cellular defense against adverse conditions such as oxidative and heat stress tend to be less efficient, thus gradually leading to the natural phenomenon of aging. Aging is linked to increased oxidative stress and is characterized by the accumulation of damaged macromolecules. The accumulation of oxidized and misfolded proteins is also accusable for various neurodegenerative pathologies that are linked to aging. Among self-defense mechanisms of cells, proteostasis network is responsible for the proper biogenesis/folding/trafficking of proteins and their elimination through proteolysis. The ubiquitin-proteasome system (UPS) is the major proteolytic mechanism that has attracted the interest of many researchers as an antiaging target. Interestingly, many natural compounds have been identified as potent UPS activators. Given that diet is a manageable environmental factor that affects aging, consumption of natural dietary products that may potentially enhance the UPS function, would contribute to increased health span and delayed onset or progression of age-related disorders. Herein, we summarize natural compounds and extracts derived from edible products that have exhibited antiaging and anti-aggregation properties and the beneficial properties have been linked to the UPS modulation. © Springer Nature Switzerland AG 2020
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