Chemicals having estrogenic activity can be released from some bisphenol a-free, hard and clear, thermoplastic resins

Background: Chemicals that have estrogenic activity (EA) can potentially cause adverse health effects in mammals including humans, sometimes at low doses in fetal through juvenile stages with effects detected in adults. Polycarbonate (PC) thermoplastic resins made from bisphenol A (BPA), a chemical that has EA, are now often avoided in products used by babies. Other BPA-free thermoplastic resins, some hypothesized or advertised to be EA-free, are replacing PC resins used to make reusable hard and clear thermoplastic products such as baby bottles. Methods: We used two very sensitive and accurate in vitro assays (MCF-7 and BG1Luc human cell lines) to quantify the EA of chemicals leached into ethanol or water/saline extracts of fourteen unstressed or stressed (autoclaving, microwaving, UV radiation) thermoplastic resins. Estrogen receptor (ER)-dependent agonist responses were confirmed by their inhibition with the ER antagonist ICI 182,780. Results: Our data showed that some (4/14) unstressed and stressed BPA-free thermoplastic resins leached chemicals having significant levels of EA, including one polystyrene (PS), and three Tritan™ resins, the latter reportedly EA-free. Exposure to UV radiation in natural sunlight resulted in an increased release of EA from Tritan™ resins. Triphenyl-phosphate (TPP), an additive used to manufacture some thermoplastic resins such as Tritan™, exhibited EA in both MCF-7 and BG1Luc assays. Ten unstressed or stressed glycol-modified polyethylene terephthalate (PETG), cyclic olefin polymer (COP) or copolymer (COC) thermoplastic resins did not release chemicals with detectable EA under any test condition. Conclusions: This hazard survey study assessed the release of chemicals exhibiting EA as detected by two sensitive, widely used and accepted, human cell line in vitro assays. Four PC replacement resins (Tritan™ and PS) released chemicals having EA. However, ten other PC-replacement resins did not leach chemicals having EA (EA-free-resins). These results indicate that PC-replacement plastic products could be made from EA-free resins (if appropriate EA-free additives are chosen) that maintain advantages of re-usable plastic items (price, weight, shatter resistance) without releasing chemicals having EA that potentially produce adverse health effects on current or future generations.This work was supported by the following NIH/NIEHS grants: R44 ES011469, 01–03 (CZY); 1R43/44 ES014806, 01–03 (CZY); subcontract (CZY, PI) on an NIH Grant 01–03 43/44ES018083-01. This work was also supported by NIH grants to MSD (P42 ES004699), and DJK and SIY (1R43ES018083-01-03, NIEHS 1R44ES019442-01-03 and NIEHS 2R44ES016964-01-03).Neuroscienc

Research on Self-Calibration of HF Ground Wave Radar Antenna Arrays

Since the performance of high-resolution direction finding algorithm for HF Ground Wave Radar (GWR) is severely degraded by sensor phase and amplitude errors, the radar system's phase calibration is the prerequisite of keeping the radar working in order. According to the characteristic of HF GWR's sea echo, this paper, based on an arbitrary triangular array, presents that Space -Time DOA(direction of arrival) Matrix Method, which is used to estimate 2D DOA under ideal conditions, can be used to estimate planar wave's DOA and sensor phase and amplitude errors simultaneously so as to achieve self-calibration. Its validity is verified not only by computer simulation, but also by comparing treatment results of measured data before and after calibration with the GPS-measured result

Memristive Non-Volatile Memory Based on Graphene Materials

Resistive random access memory (RRAM), which is considered as one of the most promising next-generation non-volatile memory (NVM) devices and a representative of memristor technologies, demonstrated great potential in acting as an artificial synapse in the industry of neuromorphic systems and artificial intelligence (AI), due its advantages such as fast operation speed, low power consumption, and high device density. Graphene and related materials (GRMs), especially graphene oxide (GO), acting as active materials for RRAM devices, are considered as a promising alternative to other materials including metal oxides and perovskite materials. Herein, an overview of GRM-based RRAM devices is provided, with discussion about the properties of GRMs, main operation mechanisms for resistive switching (RS) behavior, figure of merit (FoM) summary, and prospect extension of GRM-based RRAM devices. With excellent physical and chemical advantages like intrinsic Young’s modulus (1.0 TPa), good tensile strength (130 GPa), excellent carrier mobility (2.0 × 105 cm2∙V−1∙s−1), and high thermal (5000 Wm−1∙K−1) and superior electrical conductivity (1.0 × 106 S∙m−1), GRMs can act as electrodes and resistive switching media in RRAM devices. In addition, the GRM-based interface between electrode and dielectric can have an effect on atomic diffusion limitation in dielectric and surface effect suppression. Immense amounts of concrete research indicate that GRMs might play a significant role in promoting the large-scale commercialization possibility of RRAM devices

Efficient symmetric multiparty quantum state sharing of an arbitrary m-qubit state

We present a scheme for symmetric multiparty quantum state sharing of an arbitrary $m$-qubit state with $m$ Greenberger-Horne-Zeilinger states following some ideas from the controlled teleportation [Phys. Rev. A \textbf{72}, 02338 (2005)]. The sender Alice performs $m$ Bell-state measurements on her $2m$ particles and the controllers need only to take some single-photon product measurements on their photons independently, not Bell-state measurements, which makes this scheme more convenient than the latter. Also it does not require the parties to perform a controlled-NOT gate on the photons for reconstructing the unknown $m$-qubit state and it is an optimal one as its efficiency for qubits approaches the maximal value.Comment: 6 pages, no figures; It simplifies the process for sharing an arbitrary m-qubit state in Phys. Rev. A 72, 022338 (2005) (quant-ph/0501129

Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved

Background: Chemicals having estrogenic activity (EA) reportedly cause many adverse health effects, especially at low (picomolar to nanomolar) doses in fetal and juvenile mammals

Boosted output performance of triboelectric nanogenerator via electric double layer effect

For existing triboelectric nanogenerators ( TENGs), it is important to explore unique methods to further enhance the output power under realistic environments to speed up their commercialization. We report here a practical TENG composed of three layers, in which the key layer, an electric double layer, is inserted between a top layer, made of Al/polydimethylsiloxane, and a bottom layer, made of Al. The efficient charge separation in the middle layer, based on Volta's electrophorus, results from sequential contact configuration of the TENG and direct electrical connection of the middle layer to the earth. A sustainable and enhanced output performance of 1.22mA and 46.8 mW cm(-2) under low frequency of 3 Hz is produced, giving over 16-fold enhancement in output power and corresponding to energy conversion efficiency of 22.4%. Finally, a portable power-supplying system, which provides enough d.c. power for charging a smart watch or phone battery, is also successfully developed.ope

Effect of Annealing Temperature for Ni/AlOx/Pt RRAM Devices Fabricated with Solution-Based Dielectric

Resistive random access memory (RRAM) devices with Ni/AlOx/Pt-structure were manufactured by deposition of a solution-based aluminum oxide (AlOx) dielectric layer which was subsequently annealed at temperatures from 200 °C to 300 °C, in increments of 25 °C. The devices displayed typical bipolar resistive switching characteristics. Investigations were carried out on the effect of different annealing temperatures for associated RRAM devices to show that performance was correlated with changes of hydroxyl group concentration in the AlOx thin films. The annealing temperature of 250 °C was found to be optimal for the dielectric layer, exhibiting superior performance of the RRAM devices with the lowest operation voltage (104), the narrowest resistance distribution, the longest retention time (>104 s) and the most endurance cycles (>150)

Advanced synaptic transistor device towards AI application in hardware perspective

For the past decades, the synaptic devices for the inmemory computing have been widely investigated due to the high-efficiency computing potential and the ability to mimic biological neurobehavior. However, the conventional twoterminal synaptic memristors show drawbacks of resistance reduction caused by large-scale paralleling and asynchronous storage-reading process, which limit its development. Recently, researchers have paid attention to the transistor-like artificial synapse. Due to the existence of insulator layer and the separation of input and read terminals, the three-terminal synaptic transistors are believed to have greater potential towards artificial intelligence (AI) application fields. In this work, a summary of recent progresses and the future challenges of synaptic transistors are discussed