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In this study, the influence of carrier doping on the thermo- and galvano-magnetic effects of Bi–Sb alloys was investigated. Seven types of Bi88Sb12 alloys, namely, the undoped and 0.01, 0.02, and 0.04 at. % Te- and Sn-doped alloys, were fabricated via the spark plasma sintering method and solid phase reaction. The magnetic field dependencies of the diagonal resistivity, Hall resistivity, thermal conductivity, Seebeck thermopower, and Nernst thermopower were measured in the range of −5–5 T at 300 K, and the dimensionless figures of merit for the Seebeck and Nernst effects, i.e., the zST and zNT, respectively, were determined. As a result, both the zT values in the magnetic field were improved by the addition of a trace amount of Te. To better understand this behavior, a computational model that qualitatively describes the Seebeck, Nernst, magnetoresistance, and Hall effects, as well as the carrier thermal conductivity of Bi in the magnetic field, was developed based on the Boltzmann equation by considering the relaxation time approximation. The influence of carrier doping on the thermo-magnetic effect was considered by shifting the chemical potential with the rigid-band model in the established computational model. The computational results demonstrated that zST and zNT in the magnetic field were improved by shifting the chemical potential. These findings revealed that carrier doping could be a promising approach to improve the zT, namely, the zST for the Seebeck effect and zNT for the Nernst effect in Bi–Sb alloys in a magnetic field. [ABSTRACT FROM AUTHOR]

In ovo exposure to o,p′‐dichloro‐diphenyl‐trichloroethane (o,p′‐DDT) impairs reproduction by inducing malformation of the reproductive organs in birds, although the mechanism remains unclear. Here, we examined the effects of o,p′‐DDT on the development of the reproductive organs, the expression of genes controlling sexual differentiation, and the plasma concentrations of testosterone and estradiol in Japanese quail embryos. o,p′‐DDT‐containing sesame oil was injected into the yolk sac on Embryonic Day (E) 3 at a dose of 500, 2,000, or 8,000 μg per egg. On E15, the reproductive organs were observed; the gonads and Müllerian ducts (MDs) were sampled to measure the mRNA of steroidogenic enzymes, sex steroid receptors, anti‐Müllerian hormone (AMH), and AMH receptor 2 (AMHR2); blood samples were collected to assay plasma testosterone and estradiol levels; and the gonads were used for histological analysis. o,p′‐DDT dose‐dependently increased the prevalence of hypertrophic MDs in females and residual MDs in males. In female MDs, o,p′‐DDT dose‐dependently decreased estrogen receptor (ER) α, ERβ, and AMHR2 mRNA expression. o,p′‐DDT dose‐dependently induced left‐biased asymmetry of testis size, and ovary‐like tissue was found in the left testis after exposure to 8,000 μg per egg o,p′‐DDT, although asymmetric gene expression did not occur. o,p′‐DDT did not affect ovarian tissue but did decrease 17α‐hydroxylase/C17‐20 lyase mRNA expression and dose‐dependently increased ERβ mRNA expression. o,p′‐DDT decreased plasma testosterone concentrations in females. These findings suggest that o,p′‐DDT induces hypertrophy of the MDs and ovarian tissue formation in the left testis. Abnormal MD development may be linked to altered gene expression for sensing estrogens and AMH signals. The effects of in ovo exposure to o,p′‐dichloro‐diphenyl‐trichloroethane (o,p′‐DDT), a pesticide with estrogenic activity, on the morphology of and gene expression in the reproductive organs of Japanese quail embryos were examined. o,p′‐DDT induced Müllerian duct hypertrophy and decreased the mRNA expression of estrogen and anti‐Müllerian hormone receptors. o,p′‐DDT also induced testis size asymmetry and ovotestis formation. o,p′‐DDT may induce Müllerian duct hypertrophy and ovotestis formation via its endocrine‐disrupting actions. [ABSTRACT FROM AUTHOR]