Energy conversion from heat to electricity by highly reversible phase-transforming ferroelectrics

Searching for performant multiferroic materials attracts general research interests in energy science as they have been increasingly exploited as the conversion media among thermal, electric, magnetic and mechanical energies by using their temperature-dependent ferroic properties. Here we report a material development strategy that guides us to discover a reversible phase-transforming ferroelectric material exhibiting enduring energy harvesting from small temperature differences. The material satisfies the crystallographic compatibility condition between polar and nonpolar phases, which shows only 2.5C thermal hysteresis and high figure of merit. It stably generates 15uA electricity in consecutive thermodynamic cycles in absence of any bias fields. We demonstrate our device to consistently generate 6uA/cm2 current density near 100C over 540 complete phase transformation cycles without any electric and functional degradation. The energy conversion device can light up a LED directly without attaching an external power source. This promising material candidate brings the low-grade waste heat harvesting closer to a practical realization, e.g. small temperature fluctuations around the water boiling point can be considered as a clean energy source.Comment: 21 pages, 9 figures, 2 table

Prenatal Exposure to Organophosphates, Paraoxonase 1, and Cognitive Development in Childhood

Background: Prenatal exposure to organophosphate pesticides has been shown to negatively affect child neurobehavioral development. Paraoxonase 1 (PON1) is a key enzyme in the metabolism of organophosphates

Prenatal Phthalate Exposure Is Associated with Childhood Behavior and Executive Functioning

Background: Experimental and observational studies have reported biological consequences of phthalate exposure relevant to neurodevelopment. Objective: Our goal was to examine the association of prenatal phthalate exposure with behavior and executive functioning at 4-9 years of age. Methods: The Mount Sinai Children's Environmental Health Study enrolled a multiethnic prenatal population in New York City between 1998 and 2002 (n = 404). Third-trimester maternal urines were collected and analyzed for phthalate metabolites. Children (n = 188, n = 365 visits) were assessed for cognitive and behavioral development between the ages of 4 and 9 years. Results: In multivariate adjusted models, increased loge concentrations of low molecular weight (LMW) phthalate metabolites were associated with poorer scores on the aggression [β = 1.24; 95% confidence interval (CI), 0.15- 2.34], conduct problems (β = 2.40; 95% CI, 1.34-3.46), attention problems (β = 1.29; 95% CI, 0.16- 2.41), and depression (β = 1.18; 95% CI, 0.11-2.24) clinical scales; and externalizing problems (β = 1.75; 95% CI, 0.61-2.88) and behavioral symptom index (β = 1.55; 95% CI, 0.39-2.71) composite scales. Increased loge concentrations of LMW phthalates were also associated with poorer scores on the global executive composite index (β = 1.23; 95% CI, 0.09-2.36) and the emotional control scale (β = 1.33; 95% CI, 0.18- 2.49). Conclusion: Behavioral domains adversely associated with prenatal exposure to LMW phthalates in our study are commonly found to be affected in children clinically diagnosed with conduct or attention deficit hyperactivity disorders

Green Product Development and Order Strategies for Retailers

In this study, we consider a green supply chain to encompass two competing retailers, whose market demands include a stochastic component and a deterministic component, and we assume that consumer returns exist. We use game theory to determine the optimal decisions that retailers could make regarding greenness level and purchase quantity in either competitive environments or monopoly environments, and we perform sensitivity analysis. We show that the optimal greenness level and the purchase quantity for the stochastic demand are both higher in a competitive environment than those in a monopoly environment when the consumer return rate is low; therefore, competition is more beneficial to the increasing of the greenness level of products and the market supply than monopoly environments. We also show that, in a competitive environment, the optimal greenness level, the purchase quantity for the stochastic demand, and the revenue of retailers increase as the retail price increases, or as the wholesale price, the greenness R&D investment cost coefficient, and the consumer return rate decrease, and that this finding remains true in a monopoly environment, except that the optimal greenness level is found to increase as the return rate increases in the case of a monopoly environment. Finally, we suggest that the government should break monopolies, encourage positive competition, support small- and medium-sized companies, and subsidize the green industry to increase the greenness level of products and market supplies

Green Product Development and Order Strategies for Retailers

In this study, we consider a green supply chain to encompass two competing retailers, whose market demands include a stochastic component and a deterministic component, and we assume that consumer returns exist. We use game theory to determine the optimal decisions that retailers could make regarding greenness level and purchase quantity in either competitive environments or monopoly environments, and we perform sensitivity analysis. We show that the optimal greenness level and the purchase quantity for the stochastic demand are both higher in a competitive environment than those in a monopoly environment when the consumer return rate is low; therefore, competition is more beneficial to the increasing of the greenness level of products and the market supply than monopoly environments. We also show that, in a competitive environment, the optimal greenness level, the purchase quantity for the stochastic demand, and the revenue of retailers increase as the retail price increases, or as the wholesale price, the greenness R&D investment cost coefficient, and the consumer return rate decrease, and that this finding remains true in a monopoly environment, except that the optimal greenness level is found to increase as the return rate increases in the case of a monopoly environment. Finally, we suggest that the government should break monopolies, encourage positive competition, support small- and medium-sized companies, and subsidize the green industry to increase the greenness level of products and market supplies

Pricing Decision of the Dual-Channel Supply Chain with the Manufacturer’s Extended Warranty

With the rapid development of the internet economy, many manufacturers have opened online direct sales channels and built multi-channel distribution systems. Meanwhile, both consumers and companies are paying more attention to extended warranty services. Considering a dual-channel supply chain with a manufacturer and a retailer, we assume the manufacturer provides an extended warranty in the online direct channel and investigates the decision making of the supply chain players. We develop three game models to study this problem, and they are the basic model without extended warranty (Model B), the decentralized decision model with the manufacturer’s extended warranty (Model M), and the centralized decision model with the manufacturer’s extended warranty (Model C). The Stackelberg game method is used to solve the established model, the influence of relevant parameters on the solution result is analyzed, and different models are compared. Compared with Model B, we find that the whole supply chain always be better, but the retailer would be worse in Model M. Compared with Model M, we find that the entire supply chain always performs better in Model C. Finally, we do some sensitivity analysis

A MYB transcription factor, BnMYB2, cloned from ramie (Boehmeria nivea) is involved in cadmium tolerance and accumulation.

MYB-related transcription factors play important roles in plant development and response to various environmental stresses. In the present study, a novel MYB gene, designated as BnMYB2 (GenBank accession number: MF741319.1), was isolated from Boehmeria nivea using rapid amplification of cDNA ends (RACE) and RT-PCR on a sequence fragment from a ramie transcriptome. BnMYB2 has a 945 bp open reading frame encoding a 314 amino acid protein that contains a DNA-binding domain and shares high sequence identity with MYB proteins from other plant species. The BnMYB2 promoter contains several putative cis-acting elements involved in stress or phytohormone responses. A translational fusion of BnMYB2 with enhanced green fluorescent protein (eGFP) showed nuclear and cytosolic subcellular localization. Real-time PCR results indicated that BnMYB2 expression was induced by Cadmium (Cd) stress. Overexpression of BnMYB2 in Arabidopsis thaliana resulted in a significant increase of Cd tolerance and accumulation. Thus, BnMYB2 positively regulated Cd tolerance and accumulation in Arabidopsis, and could be used to enhance the efficiency of Cd removal with plants