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A complementary metal oxide semiconductor (CMOS) structure featuring an asymmetrically doped buried layer (ADB) is described. The ADB CMOS structure, developed for low-voltage mixed analog-digital applications, boosts the drain output resistance, transconductance and saturation current down to a 0.3-micrometer channel length. Moreover, the drain junction capacitance is reduced by virtue of the low impurity concentration beneath the drain region.

The G protein‐coupled estrogen receptor 1 (Gper1) is a membrane‐bound estrogen receptor that mediates non‐genomic action of estrogens. A Gper1‐mediating pathway has been implicated in reproductive activities in fish, including oocyte growth, but Gper1 has been characterized in only a very limited number of fish species. In this study, we cloned and characterized two genes encoding medaka (Oryzias latipes) Gper1s, namely, Gper1a and Gper1b, and phylogenic and synteny analyses suggest that these genes originate through a teleost‐specific whole genome duplication event. We found that Gper1a induced phosphorylation of mitogen‐activated protein kinase (MAPK) in 293T cells transfected with medaka Gper1s on exposure to the natural estrogen, 17β‐estradiol (E2) and a synthetic Gper1 agonist (G‐1), and treatment with both E2 and G‐1 also decreased the rate of spontaneous maturation in medaka oocytes. These findings show that the processes for oocyte growth and maturation are sensitive to estrogens and are possibly mediated through Gper1a in medaka. We also show that 17α‐ethinylestradiol (EE2), one of the most potent estrogenic endocrine‐disrupting chemicals, and bisphenol A (BPA, a weak environmental estrogen) augmented phosphorylation of MAPK through medaka Gper1s in 293T cells. Interestingly, however, treatment with EE2 or BPA did not attenuate maturation of medaka oocytes. Our findings support that Gper1‐mediated effects on oocytes are conserved among fish species, but effects of estrogenic endocrine‐disrupting chemicals on oocytes acting through Gper1 may be divergent among fish species. We cloned and characterized medaka Gper1a and Gper1b, which encode membrane‐bound estrogen receptors. Gper1a induced phosphorylation of MAPK in 293T cells transfected with medaka Gper1s on exposure to 17β‐estradiol (E2) and G‐1, and treatment with both E2 and G‐1 also decreased the rate of spontaneous maturation in medaka oocytes. Estrogenic endocrine‐disrupting chemicals, such as 17α‐ethinylestradiol and bisphenol A, also, at least in part, activated MAPK. The current results provide advance understanding on the membrane‐bound estrogen receptor in fish. [ABSTRACT FROM AUTHOR]

Freshwater zooplankton Daphnia magna has been widely used in ecotoxicology studies. During the last 20 years, it has been demonstrated that the topical application of juvenile hormone (JH) or JH analogs to mother daphnids induce male offspring production. Based on this finding, an in vivo screening validation method for chemicals with JH agonistic effect has developed. Although this screening system successfully identified a number of JH‐like chemicals, molecular mechanisms underlying the male sex‐determining process remain largely unknown. To address this issue, we established a reliable male‐ or female‐producing system using Daphnia pulex WTN6 strain by changing the rearing photoperiod. Taking advantage of this rearing system, we successfully found several factors involving male sex determination such as ionotropic glutamate receptors, protein kinase C and pantothenate. Here, we used two D. magna strains that can also control the production of female or male offspring by photoperiod differences as model species for ecotoxicology studies. We demonstrated that either treatment of antagonist of ionotropic glutamate receptors or inhibitor of protein kinase C strongly suppressed male offspring production even under male‐producing conditions. Moreover, we revealed that male sex‐determining processes are likely diverged between D. magna and D. pulex based on the current experiment. This study provides a fine experimental method for in vivo screening not only JH agonists but also JH antagonists. Moreover, using daphnids with photoperiod‐dependent sex determination manner will hugely contribute to understanding the mode‐of‐action of JH in daphnids. Two Daphnia magna strains, which could also control the production of female or male offspring by rearing photoperiod conditions, were model species for ecotoxicology studies. We demonstrated that either treatment of antagonist of ionotropic glutamate receptors or inhibitor of protein kinase C strongly suppressed male offspring production even under male‐producing conditions in both strains. This study provides a fine experimental method for in vivo screening not only juvenile hormone (JH) agonists but also JH antagonists. [ABSTRACT FROM AUTHOR]