CONSUMER PREFERENCES FOR ELECTRICITY FROM BIOENERGY AND OTHER RENEWABLES

This study ascertains residential electricity consumers' support and willingness to pay for electricity from renewable sources. Then, willingness to pay for specified renewable energy sources (solar, wind, landfill wastes, bioenergy from fast growing crops, and bioenergy from forest products wastes). Effects of demographics and environmental behaviors are estimated.Institutional and Behavioral Economics,

Adapting an Online Learning Quality Assurance Framework in a Developing Country Setting: The Case of a HEI in Malawi

Covid-19 prompted many higher education institutions (HEIs), even in developing countries like Malawi, to abruptly shift from their traditional face-to-face mode of delivery to online learning. However, quality issues with online learning remain one of the greatest challenges to acceptance of online learning by many students and stakeholders. This paper presents an action research based study at the Malawi University of Science and Technology, in which an online learning quality assurance framework is adapted to a developed country setting. The adapted framework builds on the Online Learning Consortium (OLC) Quality Scorecard for the Administration of Online Programs. The contextualization and validation of the framework is done using a modified mini-Delphi technique. Validation of the adapted framework identified key issues including financing of online learning, IT infrastructure challenges, lack of faculty training in online teaching and need for proper quality assurance instruments for monitoring online learning

Herschel Observations of the T Cha Transition Disk: Constraining the Outer Disk Properties

T Cha is a nearby (d similar to 100 pc) transition disk known to have an optically thin gap separating optically thick inner and outer disk components. Huelamo et al. recently reported the presence of a low-mass object candidate within the gap of the T Cha disk, giving credence to the suspected planetary origin of this gap. Here we present the Herschel photometry (70, 160, 250, 350, and 500 mu m) of T Cha from the "Dust, Ice, and Gas in Time" Key Program, which bridges the wavelength range between existing Spitzer and millimeter data and provide important constraints on the outer disk properties of this extraordinary system. We model the entire optical to millimeter wavelength spectral energy distribution (SED) of T Cha (19 data points between 0.36 and 3300 mu m without any major gaps in wavelength coverage). T Cha shows a steep spectral slope in the far-IR, which we find clearly favors models with outer disks containing little or no dust beyond similar to 40 AU. The full SED can be modeled equally well with either an outer disk that is very compact (only a few AU wide) or a much larger one that has a very steep surface density profile. That is, T Cha's outer disk seems to be either very small or very tenuous. Both scenarios suggest a highly unusual outer disk and have important but different implications for the nature of T Cha. Spatially resolved images are needed to distinguish between the two scenarios.DIGIT Herschel Open Time Key ProgramNASAAlexander von Humboldt FoundationEuropean CommissionAgence Nationale pour la Recherche of France PERG06-GA-2009-256513, ANR-07-BLAN-0221, ANR-2010-JCJC-0504-01CNRS/INSU, FranceAstronom

Patchwork Gridshells::Using Modularity to Facilitate Prefabrication and Simplify Construction

Modern architectural design has seen a shift towards iconic doubly-curved envelopes enclosing large column-free spaces. Gridshells have long been considered an efficient solution to such designs, but their actual use in practice has not spread worldwide. For elastic gridshells, their advantages in terms of substantial material savings can often be overshadowed by the significant challenges associated with their construction. Similarly, for rigid gridshells, the manufacture of a large number of different members and nodal connections is often a barrier to their implementation. This paper proposes an effective way of designing, fabricating and erecting gridshells. The “Patchwork Gridshell” consists of a number of efficient elastic gridshell patches assembled using rigid gridshell frames. It can easily generate a number of different configurations, use a wide range of materials, and allows more architectural expression of practical long-span forms. The benefits of combining the ingenuously simple efficiency of elastic lattices and the power of digital fabrication are demonstrated by digitally rebuilding four alternative configurations of the Japan Pavilion of the Hanover Expo 2000 as a case study. The result is a flexible digital workflow which creates large column-free spaces that are capable of being constructed efficiently by nonspecialist contractors.</p

Renal Proliferative and Phenotypic Changes in Rats With Two-Kidney, One-Clip Goldblatt Hypertension

Angiotensin II (All) is a vasoconstrictive peptide with hypertrophic and mitogenic effects on many cell types. Previous studies have shown that in vivo administration of All in rats results in proliferation of, and phenotypic changes in, many renal cell populations, but in doses also causing hypertension. Thus, it was not possible to differentiate nonhemodynamic from hypertensive effects of All. Therefore, we studied rats with renin-dependent, All-mediated hypertension (the two-kidney, oneclip Goldblatt model; mean systolic blood pressure 238 ± 48 ν 140 ± 6 mm Hg in sham-operated controls). The undipped kidneys, which were exposed to high blood pressure, developed significant glomerular and tubulointerstitial injury, tubulointerstitial cell proliferation, dense focal interstitial monocyte-macrophage influx, increased deposition of types I and IV collagen, as well as increased cellular expression of desmin and actin, in tubulointerstitial areas when examined at 11 weeks. In contrast, clipped kidneys, protected from hypertension but with high local renin expression, had minimal abnormalities. These studies suggest that in this model increased renin, and presumably All, does not mediate significant proliferative or phenotypic changes in the kidney in the absence of hypertension at 11 weeks. Am J Hypertens 1994;7:177-18

Engineering of tomato for the sustainable production of ketocarotenoids and its evaluation in aquaculture feed

Ketocarotenoids are high-value pigments used commercially across multiple industrial sectors as colorants and supplements. Chemical synthesis using petrochemical-derived precursors remains the production method of choice. Aquaculture is an example where ketocarotenoid supplementation of feed is necessary to achieve product viability. The biosynthesis of ketocarotenoids, such as canthaxanthin, phoenicoxanthin, or astaxanthin in plants is rare. In the present study, complex engineering of the carotenoid pathway has been performed to produce high-value ketocarotenoids in tomato fruit (3.0 mg/g dry weight). The strategy adopted involved pathway extension beyond β-carotene through the expression of the β-carotene hydroxylase (CrtZ) and oxyxgenase (CrtW) from Brevundimonas sp. in tomato fruit, followed by β-carotene enhancement through the introgression of a lycopene β-cyclase (β-Cyc) allele from a Solanum galapagense background. Detailed biochemical analysis, carried out using chromatographic, UV/VIS, and MS approaches, identified the predominant carotenoid as fatty acid (C14:0 and C16:0) esters of phoenicoxanthin, present in the S stereoisomer configuration. Under a field-like environment with low resource input, scalability was shown with the potential to deliver 23 kg of ketocarotenoid/hectare. To illustrate the potential of this “generally recognized as safe” material with minimal, low-energy bioprocessing, two independent aquaculture trials were performed. The plant-based feeds developed were more efficient than the synthetic feed to color trout flesh (up to twofold increase in the retention of the main ketocarotenoids in the fish fillets). This achievement has the potential to create a new paradigm in the renewable production of economically competitive feed additives for the aquaculture industry and beyond

Temporal dystrophic remodeling within the intrinsic cardiac nervous system of the streptozotocin-induced diabetic rat model

INTRODUCTION: The pathogenesis of heart failure (HF) in diabetic individuals, called “diabetic cardiomyopathy”, is only partially understood. Alterations in the cardiac autonomic nervous system due to oxidative stress have been implicated. The intrinsic cardiac nervous system (ICNS) is an important regulatory pathway of cardiac autonomic function, however, little is known about the alterations that occur in the ICNS in diabetes. We sought to characterize morphologic changes and the role of oxidative stress within the ICNS of diabetic hearts. Cultured ICNS neuronal cells from the hearts of 3- and 6-month old type 1 diabetic streptozotocin (STZ)-induced diabetic Sprague-Dawley rats and age-matched controls were examined. Confocal microscopy analysis for protein gene product 9.5 (PGP 9.5) and amino acid adducts of (E)-4-hydroxy-2-nonenal (4-HNE) using immunofluorescence was undertaken. Cell morphology was then analyzed in a blinded fashion for features of neuronal dystrophy and the presence of 4-HNE adducts. RESULTS: At 3-months, diabetic ICNS neuronal cells exhibited 30% more neurite swellings per area (p = 0.01), and had a higher proportion with dystrophic appearance (88.1% vs. 50.5%; p = <0.0001), as compared to control neurons. At 6-months, diabetic ICNS neurons exhibited more features of dystrophy as compared to controls (74.3% vs. 62.2%; p = 0.0448), with 50% more neurite branching (p = 0.0015) and 50% less neurite outgrowth (p = <0.001). Analysis of 4-HNE adducts in ICNS neurons of 6-month diabetic rats demonstrated twice the amount of reactive oxygen species (ROS) as compared to controls (p = <0.001). CONCLUSION: Neuronal dystrophy occurs in the ICNS neurons of STZ-induced diabetic rats, and accumulates temporally within the disease process. In addition, findings implicate an increase in ROS within the neuronal processes of ICNS neurons of diabetic rats suggesting an association between oxidative stress and the development of dystrophy in cardiac autonomic neurons