Three-Dimensional Spin-Orbit Coupling in a Trap

We investigate the properties of an atom under the influence of a synthetic three-dimensional spin-orbit coupling (Weyl coupling) in the presence of a harmonic trap. The conservation of total angular momentum provides a numerically efficient scheme for finding the spectrum and eigenfunctions of the system. We show that at large spin-orbit coupling the system undergoes dimensional reduction from three to one dimension at low energies, and the spectrum is approximately Landau level-like. At high energies, the spectrum is approximately given by the three-dimensional isotropic harmonic oscillator. We explore the properties of the ground state in both position and momentum space. We find the ground state has spin textures with oscillations set by the spin-orbit length scale

Characterization of genome-wide variations induced by gamma-ray radiation in barley using RNA-Seq

Background Artificial mutagenesis not only provides a new approach to increase the diversity of desirable traits for breeding new varieties but are also beneficial for characterizing the genetic basis of functional genes. In recent decades, many mutation genes have been identified which are responsible for phenotype changes in mutants in various species including Arabidopsis and rice. However, the mutation feature in induced mutants and the underlying mechanisms of various types of artificial mutagenesis remain unclear. Results In this study, we adopted a transcriptome sequencing strategy to characterize mutations in coding regions in a barley dwarf mutant induced by gamma-ray radiation. We detected 1193 genetic mutations in gene transcription regions introduced by gamma-ray radiation. Interestingly, up to 97% of the gamma irradiation mutations were concentrated in certain regions in chromosome 5H and chromosome 7H. Of the 26,745 expressed genes, 140 were affected by gamma-ray radiation; their biological functions included cellular and metabolic processes. Conclusion Our results indicate that mutations induced by gamma-ray radiation are not evenly distributed across the whole genome but located in several concentrated regions. Our study provides an overview of the feature of genetic mutations and the genes affected by gamma-ray radiation, which should contribute to a deeper understanding of the mechanisms of radiation mutation and their application in gene function analysis

Development and Experiment of Electromagnetic Pulse Crimping System for Terminal-Wire of Electric Vehicles

The safety and reliability of the energy transmission system of electric vehicles (EVs) are decided by the connection reliability of the high-voltage (HV) wire harness and terminals. When the terminal and the HV wire harness are connected by the usual mechanical crimping methods such as hydraulic pressure, there are the edges and corners on the terminal, and gaps between the wire harness and terminal, which are prone to fretting corrosion and threaten the power system. In this work, an electromagnetic pulse crimping (EMPC) system has been designed and developed for joining the Cu wire harness and the Cu terminal of the EV. When the discharge voltage is 13 kV, it can deliver the discharge current of 70 kA peak value, causing the joint of the Cu terminal and the Cu HV wire harness. Scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) were used to analyze the microstructure and element distribution of the joint interface. A good and strong metallurgical bond was obtained at the surface of the Cu HV wire harness, the Cu terminal, and each strand of the Cu HV wire harness. There were a flat interface and a wavy interface between the Cu HV wire harness and the Cu terminal because of the gap on the field shaper

Terahertz generation from laser-driven ultrafast current propagation along a wire target

Generation of intense coherent THz radiation by obliquely incidenting an intense laser pulse on a wire target is studied using particle-in-cell simulation. The laser-accelerated fast electrons are confined and guided along the surface of the wire, which then acts like a current-carrying line antenna and under appropriate conditions can emit electromagnetic radiation in the THz regime. For a driving laser intensity ∼3×1018W/cm2 and pulse duration ∼10 fs, a transient current above 10 KA is produced on the wire surface. The emission-cone angle of the resulting ∼0.15 mJ (∼58 GV/m peak electric field) THz radiation is ∼30°. The conversion efficiency of laser-to-THz energy is ∼0.75%. A simple analytical model that well reproduces the simulated result is presented

Risk assessment of deoxynivalenol in high-risk area of China by human biomonitoring using an improved high throughput UPLC-MS/MS method

A risk assessment of deoxynivalenol (DON) was recently conducted for the residents in Henan province, China, where wheat as the staple food are highly consumed. A high-throughput sensitive UPLC-MS/MS method following 96-well μElution solid-phase extraction (SPE) were developed and validated for the determination of DON biomarkers in human urine. Isotope labelled internal standard, ¹³C-DON, was used for accurate quantification. Urinary samples collected from 151 healthy Chinese aged 2–78 years were processed with and without enzyme hydrolysis to determine total and free biomarkers, respectively. DON, and de-epoxy-deoxynivalenol (DOM-1) to a lesser extent, can be frequently detected in these samples both with and without enzyme hydrolysis. Free DOM-1 was detected at low level in human urine for the first time. Total DON was detected in all samples with a mean concentration at 47.6 ng mL⁻¹. The mean and median probable daily intakes (PDI) for the whole participants, estimated to be 1.61 μg/kg bw and 1.10 μg/kg bw, both exceeded the PMTDI (1 μg/kg bw/day), indicating a potential risk for the residents in this area, especially for children and adolescents

Headspace Solid-Phase Microextraction Coupled with Gas Chromatography-Mass Spectrometric Analysis of Volatile Components of Raw and Stir-Fried Fruit of C. Pinnatifida (FCP)

Purpose: To investigate the change of volatile components associated with odor of C. Pinnatifida (FCP) fruit and its stir-fried forms.Methods: FCP fruit was stir-fried and monitored by an online-type and non-contact temperature measurement system (ONTMS). Headspace solid-phase  microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile composition of raw FCP and its various stir-fried forms.Results: The color of FCP turned darker with the stir-frying process. In all, 47 volatile compounds with contents > 1 % were identified. The major volatile components were methyl acetate (4.40 %), n-hexane (2.90 %), 2-methyl-furan (1.80 %), 3-methyl-butyraldehyde (3.64 %), hexanal (2.08 %), furaldehyde (5.77 %), and D-limonene (7.99 %) in raw FCP. Following stir-frying, the contents of furaldehyde, 5- methyl-furaldehyde, methyl acetate, 2-methyl-butyraldehyde, D-limonene and 2-methyl-furaldehyde were altered significantly, which might have resulted in odor changes.Conclusion: HS-SPME coupled with GC-MS is a rapid and eco-friendly method with the potential to analyze volatile compounds in raw and processed FCP.Keywords: Crataegus pinnatifida, Stir-frying, Online-type and non-contact temperature measurement system, Headspace solid-phase microextraction, Volatile components, Odo

Spatially Explicit Global Hotspots Driving China's Mercury Related Health Impacts

Over 100 nations signed the Minamata Convention on Mercury to control the adverse effects of mercury (Hg) emissions on human beings. A spatially explicit analysis is needed to identify the specific sources and distribution of Hg-related health impacts. This study maps China's Hg-related health impacts and global supply chain drivers (i.e., global final consumers and primary suppliers) at a high spatial resolution. Here we show significant spatial heterogeneity in hotspots of China's Hg-related health impacts. Approximately 1% of the land area holds only 40% of the Chinese population but nearly 70% of the fatal heart attack deaths in China. Moreover, approximately 3% of the land area holds nearly 60% of the population but 70% of the intelligence quotient (IQ) decrements. The distribution of hotspots of China's Hg-related health impacts and global supply chain drivers are influenced by various factors including population, economy, transportation, resources, and dietary intake habits. These spatially explicit hotspots can support more effective policies in various stages of the global supply chains and more effective international cooperation to reduce Hg-related health impacts. This can facilitate the successful implementation of the Minamata Convention on Mercury