Breathers in FPU systems, near and far from the phonon band

There exists a recent mathematical proof on the existence of small amplitude breathers in FPU systems near the phonon band, which includes a prediction of their amplitude and width. In this work we obtain numerically these breathers, and calculate the range of validity of the predictions, which extends relatively far from the phonon band. There exist also large amplitude breathers with the same frequency, with the consequence that there is an energy gap for breather creation in these systems.Comment: 3 pages, 2 figures, proceeding of the conference on Localization and to and Energy Transfer in Nonlinear Systems, June 17-21, 2002, San Lorenzo de El Escorial, Madrid, Spain. To be published by World Scientifi

Environmental justice and transportation equity: a review of MPOs

Book ChapterSurface transportation policies at the local, regional, state, and national levels have a direct impact on urban land use and development patterns. The types of transportation facilities and services in which public funds are invested provide varying levels of access to meet basic social and economic needs. The way regions develop land dictates the need for certain types of transportation, and on the other hand, the transportation options in which regions invest influence patterns of urban development. While many lament the trend toward suburban sprawl as damaging to the environment or unaesthetic, those who support social equity should also be concerned about the associated impacts. Substantial investment in highway development and other transportation programs that encourage private automobile use has supported low-density developments that extend increasingly farther and farther from the central city, and to residential and commercial areas that are increasingly spread out, producing "edgeless cities" (Lang 2003). In addition to being costly to state and local governments, transportation policies that encourage these growth patterns play a substantial role in producing some indirect, negative social and economic effects, including perpetuating residential segregation and exacerbating the inability of minorities to access entry-level employment, which is increasingly found in suburban areas. MPOs are well suited to provide leadership in the areas of metropolitan development and civil rights

Identification and molecular genetic analysis of the cichorine gene cluster in Aspergillus nidulans

We recently demonstrated that the phytotoxin cichorine is produced by Aspergillus nidulans. Through a set of targeted deletions, we have found a cluster of seven genes that are required for its biosynthesis. Two of the deletions yielded molecules that give information about the biosynthesis of this metabolite

Orchestration of the S-phase and DNA damage checkpoint pathways by replication forks from early origins

The S-phase checkpoint activated at replication forks coordinates DNA replication when forks stall because of DNA damage or low deoxyribonucleotide triphosphate pools. We explore the involvement of replication forks in coordinating the S-phase checkpoint using dun1Δ cells that have a defect in the number of stalled forks formed from early origins and are dependent on the DNA damage Chk1p pathway for survival when replication is stalled. We show that providing additional origins activated in early S phase and establishing a paused fork at a replication fork pause site restores S-phase checkpoint signaling to chk1Δ dun1Δ cells and relieves the reliance on the DNA damage checkpoint pathway. Origin licensing and activation are controlled by the cyclin–Cdk complexes. Thus, oncogene-mediated deregulation of cyclins in the early stages of cancer development could contribute to genomic instability through a deficiency in the forks required to establish the S-phase checkpoint

Cosmic Microwave Background Polarization

Cosmic microwave background (CMB) anisotropy is our richest source of cosmological information; the standard cosmological model was largely established thanks to study of the temperature anisotropies. By the end of the decade, the Planck satellite will close this important chapter and move us deeper into the new frontier of polarization measurements. Numerous ground--based and balloon--borne experiments are already forging into this new territory. Besides providing new and independent information on the primordial density perturbations and cosmological parameters, polarization measurements offer the potential to detect primordial gravity waves, constrain dark energy and measure the neutrino mass scale. A vigorous experimental program is underway worldwide and heading towards a new satellite mission dedicated to CMB polarization.Comment: Review given at TAUP 2005; References added; Additional reference

Optimization of municipal solid waste management using externality costs

Economic and environmental impacts associated with solid waste management (SWM) systems should be considered to ensure sustainability of such systems. Societal life cycle costing (S-LCC) can be used for this purpose since it includes “budget costs” and “externality costs.” While budget costs represent market goods and services in monetary terms, i.e. economic impacts, externality costs include effects outside the economic system such as environmental impacts (translated in monetary terms).1 Numerous models have been developed to determine the environmental and economic impacts associated with SWM systems (e.g., EASETECH2) by using “what-if” scenario analyses. While these models are an essential foundation that enables a systematic integrated analysis of SWM systems, they do not provide information about the overall optimal solution as done with optimization models such as SWOLF.3 This study represents the first attempt to optimize SWM systems using externality costs in SWOLF. The assessment identifies the waste strategy that minimizes externality costs and other criteria (budget costs and landfilling) for a specific case study. The latter represents a hypothetical U.S. county with annual waste generation of 320,000 Mg. The externality cost includes the damage costs of fossil CO2, CH4, N2O, PM2.5, PM10, NOX, SO2 , VOC, CO, NH3, CO, Hg, Pb, Cd, Cr (VI), Ni, As, and dioxins. Table 1 shows the results of the optimization including: i) optimization criteria, ii) waste flows and iii) eco-efficiency indicator (ratio between externality costs and budget costs). Minimal externality costs are obtained when incinerating most of the waste (88%) and commingled collection of recyclables (12%). The eco-efficiency of this waste strategy corresponds to -0.6, i.e. its environmental benefits (negative externality costs) correspond to approximately half of its budget costs. On the other hand, there is the solution with minimal budget costs (100% of the waste is landfilled) in which the environmental load (positive externality cost) represent one third of the budget costs (positive eco-efficiency indicator). In between these options, there is a strategy with minimal landfilling in which the organic waste is sent to anaerobic digestion, the recyclables to a single stream MRF and the residual to a mixed waste MRF. Most of the externality costs of the three strategies stem from SO2, NOx and GHG as suggested by Woon & Lo.4 The case study shows that waste solutions identified by optimization modelling differ from common SWM systems selected for analysis in state-of-the-art accounting modelling Please click Additional Files below to see the full abstract

Evaluation of Externality Costs in Life-Cycle Optimization of Municipal Solid Waste Management Systems

The development of sustainable solid waste management (SWM) systems requires consideration of both economic and environmental impacts. Societal life-cycle costing (S-LCC) provides a quantitative framework to estimate both economic and environmental impacts, by including “budget costs” and “externality costs”. Budget costs include market goods and services (economic impact), whereas externality costs include effects outside the economic system (e.g., environmental impact). This study demonstrates the applicability of S-LCC to SWM life-cycle optimization through a case study based on an average suburban U.S. county of 500 000 people generating 320 000 Mg of waste annually. Estimated externality costs are based on emissions of CO₂, CH₄, N₂O, PM_2.5, PM₁₀, NO_<i>x</i>, SO₂, VOC, CO, NH₃, Hg, Pb, Cd, Cr (VI), Ni, As, and dioxins. The results indicate that incorporating S-LCC into optimized SWM strategy development encourages the use of a mixed waste material recovery facility with residues going to incineration, and separated organics to anaerobic digestion. Results are sensitive to waste composition, energy mix and recycling rates. Most of the externality costs stem from SO₂, NO_<i>x</i>, PM_2.5, CH₄, fossil CO₂, and NH₃ emissions. S-LCC proved to be a valuable tool for policy analysis, but additional data on key externality costs such as organic compounds emissions to water would improve future analyses

Inhibition of Tau Aggregation by Three Aspergillus nidulans Secondary Metabolites: 2,ω-Dihydroxyemodin, Asperthecin, and Asperbenzaldehyde

This is the published version. Copyright 2014 George Theime Verlag. All rights reserved.The aggregation of the microtubule-associated protein tau is a significant event in many neurodegenerative diseases including Alzheimerʼs disease. The inhibition or reversal of tau aggregation is therefore a potential therapeutic strategy for these diseases. Fungal natural products have proven to be a rich source of useful compounds having wide varieties of biological activity. We have screened Aspergillus nidulans secondary metabolites containing aromatic ring structures for their ability to inhibit tau aggregation in vitro using an arachidonic acid polymerization protocol and the previously identified aggregation inhibitor emodin as a positive control. While several compounds showed some activity, 2,ω-dihydroxyemodin, asperthecin, and asperbenzaldehyde were potent aggregation inhibitors as determined by both a filter trap assay and electron microscopy. In this study, these three compounds were stronger inhibitors than emodin, which has been shown in a prior study to inhibit the heparin induction of tau aggregation with an IC50 of 1–5 µM. Additionally, 2,ω-dihydroxyemodin, asperthecin, and asperbenzaldehyde reduced, but did not block, tau stabilization of microtubules. 2,ω-Dihydroxyemodin and asperthecin have similar structures to previously identified tau aggregation inhibitors, while asperbenzaldehyde represents a new class of compounds with tau aggregation inhibitor activity. Asperbenzaldehyde can be readily modified into compounds with strong lipoxygenase inhibitor activity, suggesting that compounds derived from asperbenzaldehyde could have dual activity. Together, our data demonstrates the potential of 2,ω-dihydroxyemodin, asperthecin, and asperbenzaldehyde as lead compounds for further development as therapeutics to inhibit tau aggregation in Alzheimerʼs disease and neurodegenerative tauopathies

Multiple myeloma presenting with high-output heart failure and improving with anti-angiogenesis therapy: two case reports and a review of the literature

<p>Abstract</p> <p>Introduction</p> <p>Common manifestations of multiple myeloma include osteolytic lesions, cytopenias, hypercalcemia, and renal insufficiency. Patients may also exhibit heart failure which is often associated with either past therapy or cardiac amyloidosis. A less recognized mechanism is high-output heart failure. Diuretic therapy in this setting has little efficacy in treating the congested state. Furthermore, effective pharmacotherapy has not been established. We report two patients with multiple myeloma and high-output heart failure who failed diuretic therapy. The patients were given dexamethasone in conjunction with lenalidomide and thalidomide, respectively. Shortly thereafter, each patient demonstrated a significant improvement in symptoms. This is the first report of successful treatment of multiple myeloma-induced high-output failure via the utilization of these agents.</p> <p>Case presentation</p> <p>Two patients with multiple myeloma were evaluated for volume overload. The first was a 50-year-old man with refractory disease. Magnetic resonance imaging demonstrated diffuse marrow replacement throughout the pelvis. Cardiac catheterization conveyed elevated filling pressures and a cardiac output of 15 liters/minute. He quickly decompensated and required mechanical ventilation. The second patient was a 61-year-old man recently diagnosed with multiple myeloma and volume overload. Skeletal survey demonstrated numerous lytic lesions throughout the pelvis. His cardiac catheterization also conveyed elevated filling pressures and a cardiac output of 10 liters/minute. Neither patient responded to diuretic therapy and they were subsequently started on dexamethasone plus lenalidomide and thalidomide, respectively. The first patient's brisk diuresis allowed for extubation within 48 hours after the first dose. He had a net negative fluid balance of 15 liters over 10 days. The second patient also quickly diuresed and on repeat cardiac catheterization, his cardiac output had normalized to 4.7 liters/minute.</p> <p>Conclusion</p> <p>Multiple myeloma can cause high-output failure. The mechanism is likely extensive bony involvement causing innumerable intramedullary arteriovenous fistulas. Diuretic therapy is not effective in treating this condition. Lenalidomide and thalidomide, both of which inhibit angiogenesis, seem to be viable treatment options. Based on the rapid and effective results seen in these two patients, a potential novel mechanism of 'pharmacologic fistula ligation' with these agents may be the most effective way to treat this presentation.</p