L\'evy Distribution of Single Molecule Line Shape Cumulants in Low Temperature Glass

We investigate the distribution of single molecule line shape cumulants, $\kappa_1,\kappa_2,...$, in low temperature glasses based on the sudden jump, standard tunneling model. We find that the cumulants are described by L\'evy stable laws, thus generalized central limit theorem is applicable for this problem.Comment: 5 pages, 3 figure

Hybrid (Gas and Geothermal) Greenhouse Simulations Aimed at Optimizing Investment and Operative Costs: A Case Study in NW Italy

Generally, greenhouses are high energy-consuming, sometimes accounting for 50% of the cost of greenhouse production. Geothermal energy plays a very important role in maintaining the desired temperature and reducing energy consumption. This work deals with a project of a hybrid heating plant (97% geothermal energy and 3% gas-condensing boiler) for the innovative Plant Phenotyping Greenhouse at the University Campus in Grugliasco (few km West of the city of Turin). The aim of the study is to testify to the energy efficiency of this kind of hybrid plant as well as its economic sustainability. Numerical simulations of a GRT were used to calibrate the system and verify that the software reasonably modeled the real case. They helped to correctly size the geothermal plant, also providing data about the thermal energy storage and production during on and off plant cycles. The results show a thermal power of 50.92 kW over 120 days of plant operation, in line with the expected energy needs to meet the base load demand. Long-term results further ensure a negligeable impact on the ground, with a thermal plume between 5 and 10 m from the plant, reducing substantially in a few months after switching off the plant

Strategic raw material inventory optimization

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2007.Includes bibliographical references (p. 77-78).The production of aerospace grade titanium alloys is concentrated in a relatively small number of producers. The market for these materials has always been cyclical in nature. During periods of high demand, metal producers claim to operate near full capacity utilization. During periods of reduced demand, metal producers struggle to remain profitable. Additionally, the manufacturing processes for aerospace grade titanium alloys are capital intensive and require long lead-times in order to bring new capacity online. The combination of these factors often results in an inflexible titanium alloy raw material supply chain for Pratt & Whitney. At the same time, Pratt & Whitney experiences a variety of rare but disruptive events within the supply chain that affect their raw material requirements. Examples of these disruptive events include customer drop-in orders, manufacturing complications resulting in scrapped material, and planning deficiencies. In order to protect engine and spare part customers from delayed deliveries due to long lead-time raw materials, Pratt & Whitney holds a strategic inventory of various titanium alloy raw material.(cont.) This thesis presents a mathematical model utilizing a Compound Poisson Process that can be used to optimize the amount of strategic titanium alloy raw material held by Pratt & Whitney. The associated mathematical algorithms were programmed into Microsoft Excel creating the Strategic Raw Material Inventory Calculator. Historical data was then collected and used with this unique tool to calculate service levels at current inventory levels as well as optimized inventory levels under various scenarios.by Robin L. Vacha, Jr.S.M.M.B.A

Do In-Vehicle Advance Signs Benefit Older and Younger Driver Intersection Performance?

An experimental study was conducted to determine if intersection behavior of those 18 to 24 and 65+ benefited from advanced in-vehicle signs presented in a head-up display (HUD) format. The University of Calgary Driving Simulator (UCDS) was used to determine whether intersection performance improved in the presence of several advanced signs or whether unwanted adaptive behaviors occurred (e.g., increasing speed to run the light instead of stopping). Invehicle signs facilitated an increase in stopping occurrences for both younger and older drivers at intersections with relatively short yellow onsets. In addition, eye movement analysis revealed significant age effects with regard to vertical and horizontal gaze variablity, with younger drivers showing increases in vertical gaze variability compared to the older drivers. Younger drivers also looked more often and had longer percentage of durations fixating on the HUD compared to the older drivers

Two different charge-separation pathways in photosystem II

Charge separation is an essential step in the conversion of solar energy into chemical energy in photosynthesis. To investigate this process, we performed transient absorption experiments at 77 K with various excitation conditions on the isolated Photosystem II reaction center preparations from spinach. The results have been analyzed by global and target analysis and demonstrate that at least two different excited states, (Ch

Developments in the Photonic Theory of Fluorescence

Conventional fluorescence commonly arises when excited molecules relax to their ground electronic state, and most of the surplus energy dissipates in the form of photon emission. The consolidation and full development of theory based on this concept has paved the way for the discovery of several mechanistic variants that can come into play with the involvement of laser input – most notably the phenomenon of multiphoton-induced fluorescence. However, other effects can become apparent when off-resonant laser input is applied during the lifetime of the initial excited state. Examples include a recently identified scheme for laser-controlled fluorescence. Other systems of interest are those in which fluorescence is emitted from a set of two or more coupled nanoemitters. This chapter develops a quantum theoretical outlook to identify and describe these processes, leading to a discussion of potential applications ranging from all-optical switching to the generation of optical vortices

General practitioner workforce sustainability to maximise effective and equitable patient care: a realist review

Background: Global and United Kingdom (UK) primary care face significant General Practitioner (GP) workforce shortages. Worldwide strategies to address this issue include the introduction of additional healthcare professionals and increasing technology utilisation, to reduce GP workload. However, whether these strategies can sustain the GP workforce remains unclear. Our review examines the factors that sustain and enable GPs to flourish. Aim: To examine how general practice work and healthcare systems support GP workforce sustainability and effective and equitable patient care. Design & setting: A realist review of existing empirical and grey literature. The search strategy encompassed six electronic databases. Method: Realist synthesis involved (1) finding existing theories, (2) searching for evidence, (3) selecting articles, (4) extracting data, and (5) synthesising evidence/drawing conclusions. Context-Mechanism-Outcome Configurations were developed using extracted data and patient and public involvement/stakeholder suggestions to refine our programme theory. Results: 168 documents were included. Findings underscore the importance of meaningful work and engagement; relationships across individuals, organisations, and communities; and learning and development. We emphasise the need for congruence between GPs’ core values and their work; cumulative-knowledge building; system agility; psychological safety; and direct human connections. Conclusion: General practice structures, policies, and practices, and the interactions they facilitate, are crucial for the sustainability of the workforce. Collaboration among GPs, the public, and national policymakers is essential for implementing the principles from this review. Future systems should enable personalised care; sustain meaningful work and relationships; facilitate meaning-making; and promote agency, agility, and flexibility to enable GPs to utilise, adapt, and cultivate expertise

Rapid and Efficient Clearance of Blood-borne Virus by Liver Sinusoidal Endothelium

The liver removes quickly the great bulk of virus circulating in blood, leaving only a small fraction to infect the host, in a manner characteristic of each virus. The scavenger cells of the liver sinusoids are implicated, but the mechanism is entirely unknown. Here we show, borrowing a mouse model of adenovirus clearance, that nearly all infused adenovirus is cleared by the liver sinusoidal endothelial cell (LSEC). Using refined immunofluorescence microscopy techniques for distinguishing macrophages and endothelial cells in fixed liver, and identifying virus by two distinct physicochemical methods, we localized adenovirus 1 minute after infusion mainly to the LSEC (∼90%), finding ∼10% with Kupffer cells (KC) and none with hepatocytes. Electron microscopy confirmed our results. In contrast with much prior work claiming the main scavenger to be the KC, our results locate the clearance mechanism to the LSEC and identify this cell as a key site of antiviral activity

Prospect Theory in the Heterogeneous Agent Model

Using the Heterogeneous Agent Model framework, we incorporate an extension based on Prospect Theory into a popular agent-based asset pricing model. The extension covers the phenomenon of loss aversion manifested in risk aversion and asymmetric treatment of gains and losses. Using Monte Carlo methods, we investigate behavior and statistical properties of the extended model and assess its relevance with respect to financial data and stylized facts. We show that the Prospect Theory extension keeps the essential underlying mechanics of the model intact, however, that it changes the model dynamics considerably. Stability of the model increases but the occurrence of the fundamental strategy is more extreme. Moreover, the extension shifts the model closer to the behavior of real-world stock markets

Homogeneous Hydrophobic-Hydrophilic Surface Patterns Enhance Permeation of Nanoparticles through Lipid Membranes

We employ coarse-grained molecular dynamics simulations to understand why certain interaction patterns on the surface of a nanoparticle promote its translocation through a lipid membrane. We demonstrate that switching from a random, heterogeneous distribution of hydrophobic and hydrophilic areas on the surface of a nanoparticle to even, homogeneous patterns substantially flattens the translocation free-energy profile and dramatically enhances permeation. We then proceed to construct a more detailed coarse-grained model of a nanoparticle with flexible hydrophobic and hydrophilic ligands arranged into striped domains. Molecular dynamics simulations of these nanoparticles show that the terminal groups of the ligands tend to arrange themselves into homogeneous patterns, despite the underlying striped domains. These observations are linked to recent experimental studies