New innovations in agricultural biotech: Consumer acceptance of topical RNAi in rice production

To test the market viability of a non-GMO topical RNAi insect control, we conducted a Willingness-To-Pay (WTP) survey in the USA, Canada, Australia, France, and Belgium to elicit whether consumers need a premium or discount for: (1) a hypothetical GMO rice variety using the Bacillus thuringiensis (Bt) gene for insect control; and (2) a hypothetical non-GMO rice variety using topical RNAi spray for insect control. The survey was designed based on a Multiple Price List (MPL) format where respondents selected their preferred insect control technology; i.e., conventional, GMO Bt, or non-GMO RNAi, at different prices. Participants' responses were analyzed using an interval regression model to generate WTP premiums and discounts for each country with control variables for demographic influences. Further, we asked consumers their Willingness-To-Consume (WTC) food produced with GM and RNAi technologies respectively and evaluated WTC differences using a McNemar matched pairs test in each country. The results from our study clearly show that: (1) consumers in the USA, Canada, Australia, and France still require a discount for rice produced with topical RNAi compared to conventionally-produced rice (p < 0.05), (2) consumers in the USA, Canada, Australia, France, and Belgium would need an additional 30–40% discount to purchase Bt rice over rice produced with topical RNAi (p < 0.05), and (3) consumers in all countries were more willing to consume rice produced with non-GM RNAi than with GM Bt technology (p < 0.05). These findings suggest consumers differentiate among biotechnology solutions and consumers may prefer topical RNAi insect control to transgenic GMO insecticides.     

A comparative study on the performance of M (Rh,Ru, Ni)-promoted metallurgical waste driven catalysts for H2 production by glycerol steam reforming

A comprehensive study was conducted on the performance of M-promoted (M = 1%Ru, 1%Rh, 5%Ni) upgraded slag oxide metallurgical waste catalysts (M-UGSO) for hydrogen production by glycerol steam reforming (GSR). The results confirmed that the tendency of the incorporated metal to interact with Mg/Fe containing species within UGSO plays a key role in the surface availability of the corresponding metal, structural changes after reduction, and catalyst stability. Aside its best stability, 5% Ni-UGSO showed a performance (glycerol conversion to gaseous products of 100% and H₂ yield of 74%) comparable with 1% Rh-UGSO (100% and 78%, respectively) or even surpassing that of 1% Ru-UGSO (94% and 71%, respectively), as noble metal-based catalysts. Synergistic cooperation was achieved by incorporated metals (M) and Fe/Mg containing species within UGSO, resulting in enhanced glycerol and water activation. The weakest results of Ru-UGSO could be justified by lack of propensity for MgO–RuO₂ interaction on UGSO surface.     

DETERMINATION OF TIME-DEPENDENT CONSTITUTIVE MODEL PARAMETERS FOR MICROCRYSTALLINE CELLULOSE

ABSTRACT

Material parameters of a time-dependent elasto-viscoplaslic constitutive model, proposed by Adachi and Oka, have been determined for microcrystalline cellulose. Adachi and Oka model has eight material parameters, with five of them (i.e., consolidation index, swelling index, critical index, shear modulus, and Poisson's ratio) same as those in the more commonly used in time-independent modified Cam-clay model, and remaining three parameters account for time-dependency. To measure the time-dependent parameters, constant strain-rate conventional triaxial compression (CTC) test was designed and conducted using Penn Slate's flexible-boundary cubical triaxial tester (CTT) with microcrystalline cellulose as the test material. To deposit the powder, the sprinkle filling method was used in a layer by layer fashion with a small spoon. The three time-dependent Adachi and Oka parameters were determined from these tests. Adachi and Oka model was verified by comparing the predicted values from the model with measured values from the CTT at 0.05 level of significance. Results showed that: 1) there were no significant differences (p > 0.05) between measured and predicted HTC responses at all loading rates; 2) failure values were predicted accurately (p > 0.05); and 3) there were significant differences (p < 0.05) between measured and predicted CTC responses at all loading rates.     

Measurement of Thermal Neutron Cross Section of 137Cs(n, γ)138Cs Reaction

A calculational model for a modified diffusion coefficient has been developed to incorporate the neutron streaming effect in heterogeneous low-density channels accurately into diffusion theory calculations. The model uses a supercell, and the axial and radial diffusion coefficients of the heterogeneous inner cell are so defined that they can reproduce Benoist's axial and radial diffusion coefficients of the supercell when the diffusion coefficient of the outer cell is given as 1/3 Σ_tr . In the case of the axial diffusion coefficient, the axial buckling effect is taken into account by modifying the neutron path length within the streaming channel in calculating the collision probabilities. This model has been applied to an RZ fast reactor Core model with a gas expansion module (GEM). By using the axial diffusion coefficient obtained with the presented model, calculational error of GEM worth was reduced to less than 1/7 compared to the formula of Rowlands and Eaton.     

Broadening the lens for the governance of emerging technologies: Care ethics and agricultural biotechnology

In this paper we argue that insights from feminist perspectives, particularly in the form of an ethics of care, have a number of advantages when used as a lens through which to consider questions relevant to the governance of emerging technologies. We highlight how an emphasis on central themes of importance in feminist theory and care ethics such as relationality, contextuality, dependence, power, affect, and narrative can shine a light on a number of salient issues that are typically missed by the dominant and largely consequentialist risk assessment frame. We argue that the care ethics lens is a better fit when technologies are understood not simply as devices designed to create a certain end experience for a user but as transformative systems that smuggle in numerous social and political interests. The advantages of these care ethics themes for emerging technologies are illustrated through a detailed consideration of agricultural biotechnology. We show how the feminist care ethics lens might have anticipated the very questions that have proved themselves to be the sticking points for this technology. We therefore suggest that applying a care ethics lens can significantly broaden the frame of appraisal processes used for the governance of emerging technologies and usefully grant legitimacy to questions and concerns that are prominent in public discourse but typically left out of practices of risk assessment.     

Characterization and productivity of cassava waste and its use as an energy source

This study sought to quantify and characterize cassava waste as fuel. The wastes from three cultivars were collected to study and were divided into three distinct parts of the cassava plant: seed stem, thick stalks, and thin stalks. Physical and chemical analyzes were carried out to determine the elemental composition of the waste: volatile matter; fixed carbon; ash; moisture; lignin; cellulose; hemicellulose; ash composition and higher heating value were determined. We conducted a thermogravimetric analysis in oxidizing and inert atmospheres to study the behavior of the waste as fuel. The root productivity obtained ranged from 7.7 to 13.0 t ha⁻¹ yr⁻¹ on a dry basis (db), and the ratio between waste and roots varied from 0.36 to 0.91. The physical and chemical properties of cassava waste are analogous to those of woody biomass regarding the elemental composition, the higher heating value, and thermogravimetric analysis. Ash content varied from 2.5% to 3.5%, reaching around 6.0% in samples unwashed. Approximately 60% of the ashes are alkali oxides, especially P₂O₅, K₂O, and CaO, which have low melting points. The alkali index calculated suggests that there is a strong tendency that the combustion process leads to ash fouling and the formation of ash deposits.     

Inertization of Coal Ashes by the Vitrification Technique: A Mixture Design Approach

This article deals with the study of the vitrification mechanism as an inertization method for coal ashes contaminated with heavy metals. Ashes from coal (thermoelectric) and wastes from mining of fluorite and feldspar and from plating were used to compose vitreous systems using a mixture design. The chemical composition of the wastes was determined by XRF and the formulations were melted at 1450°C for 2 h using 10% (mass) of Na₂CO₃ (as a fluxing agent). The glasses were poured into a mold and annealed (600°C). The characteristic temperatures were determined by thermal analysis (DTA, air, 20°C/min) and the mechanical behavior by HV. As a result, the softening temperature is strongly dependent on silica content of each glass, and the fluorite residue, being composed mainly by silica, strongly affects on the glass transition (T_g) and softening (T_s) temperatures. The hardness by micro-indentation of all glasses is mainly affected by the plating (galvanic) residue due to the high iron and zinc content of this waste.