An integrated approach to climate change, income distribution, employment, and economic growth

A demand-driven growth model involving capital accumulation and the dynamics of greenhouse gas (GHG) concentration is set up to examine macroeconomic issues raised by global warming, e.g. effects on output and employment of rising levels of GHG; offsets by mitigation; relationships among energy use and labor productivity, income distribution, and growth; the economic significance of the Jevons and other paradoxes; sustainable consumption and possible reductions in employment; and sources of instability and cyclicality implicit in the two-dimensional dynamical sysem. The emphasis is on the combination of biophysical limits and Post-Keynesian growth theory and the qualitative patterns of system adjustment and the dynamics that emerge

3D chemical characterization of frozen hydrated hydrogels using ToF-SIMS with argon cluster sputter depth profiling

Hydrogels have been used extensively in bioengineering as artificial cell culture supports. Investigation of the interrelationship between cellular response to the hydrogel and its chemistry ideally requires methods that allow characterization without labels and can map species in three dimensional to follow biomolecules adsorbed to, and absorbed into, the open structure before and during culture. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has the potential to be utilized for through thickness characterization of hydrogels. The authors have established a simple sample preparation procedure to successfully achieve analysis of frozen hydrated hydrogels using ToF-SIMS without the need for dry glove box entry equipment. They demonstrate this on a poly(2-hydroxyethyl methacrylate) (pHEMA) film where a model protein (lysozyme) is incorporated using two methods to demonstrate how protein distribution can be determined. A comparison of lysozyme incorporation is made between the situation where the protein is present in a polymer dip coating solution and where lysozyme is in an aqueous medium in which the film is incubated. It is shown that protonated water clusters H(H2O)nþ where n ¼ 5–11 that are indicative of ice are detected through the entire thickness of the pHEMA. The lysozyme distribution through the pHEMA hydrogel films can be determined using the intensity of a characteristic amino acid secondary ion fragment

Tomography of (2, 1) and (3, 2) magnetic island structures on Tokamak Fusion Test Reactor

High-resolution electron cyclotron emission (ECE) image reconstruction has been used to observe (m,n)=(2,1) and (3, 2) island structures on Tokamak Fusion Test Reactor [Plasma Phys. Controlled. Fusion 33, 1509 (1991)], where m and n are the poloidal and the toroidal mode number, respectively. The observed island structure is compared with other diagnostics, such as soft x-ray tomography and magnetic measurements. A cold elliptic island is observed after lithium pellet injection. Evidence for the enhancement of the heat transfer due to the island is observed. A relaxation phenomenon due to the m=2 mode is newly observed in Ohmic plasmas

Removal of volatile phenols from wine using crosslinked cyclodextrin polymers

Volatile phenols have been implicated as contributors to off-odors associated with taints from bushfire smoke and microbial spoilage. Various methods for the amelioration of off-odors have been evaluated, but to date, they have not included cyclodextrin (CD) polymers. In the current study, two CD polymers were prepared from β- and γ-CD, using hexamethylene diisocyanate (HDI) as a crosslinking agent. Adsorption tests were performed with four volatile phenols (guaiacol, 4-methylguaiacol, 4-ethylguaiacol and 4-ethylphenol) at concentrations up to 1 mg/L. The removal of volatile phenols by CD polymers achieved equilibrium almost instantly, with isotherm tests suggesting an adsorption capacity of 20.7 µg of volatile phenol per gram of polymer. Langmuir and Freundlich models were subsequently used to fit the data. In batch adsorption tests, the CD polymers achieved 45 to 77% removal of volatile phenols. Polymer reusability was also evaluated and was found to be excellent. A comparison between volatile phenol adsorption by CDs vs. CD polymers, determined using a novel four-phase headspace solid-phase microextraction (HS-SPME) method for gas chromatography-mass spectrometry (GC-MS), suggests CD polymers offer several advantages for use by the wine industry.Chao Dang, Vladimir Jiranek, Dennis K. Taylor and Kerry L. Wilkinso

Revealing cytokine-induced changes in the extracellular matrix with secondary ion mass spectrometry

AbstractCell-secreted matrices (CSMs), where extracellular matrix (ECM) deposited by monolayer cell cultures is decellularized, have been increasingly used to produce surfaces that may be reseeded with cells. Such surfaces are useful to help us understand cell–ECM interactions in a microenvironment closer to the in vivo situation than synthetic substrates with adsorbed proteins. We describe the production of CSMs from mouse primary osteoblasts (mPObs) exposed to cytokine challenge during matrix secretion, mimicking in vivo inflammatory environments. Time-of-flight secondary ion mass spectrometry data revealed that CSMs with cytokine challenge at day 7 or 12 of culture can be chemically distinguished from one another and from untreated CSM using multivariate analysis. Comparison of the differences with reference spectra from adsorbed protein mixtures points towards cytokine challenge resulting in a decrease in collagen content. This is supported by immunocytochemical and histological staining, demonstrating a 44% loss of collagen mass and a 32% loss in collagen I coverage. CSM surfaces demonstrate greater cell adhesion than adsorbed ECM proteins. When mPObs were reseeded onto cytokine-challenged CSMs they exhibited reduced adhesion and elongated morphology compared to untreated CSMs. Such changes may direct subsequent cell fate and function, and provide insights into pathological responses at sites of inflammation