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Solid-state qubits with a photonic interface is very promising for quantum networks. Color centers in silicon carbide have shown excellent optical and spin coherence, even when integrated with membranes and nanostructures. Additionally, nuclear spins coupled with electron spins can serve as long-lived quantum memories. Pioneering work previously has realized the initialization of a single nuclear spin and demonstrated its entanglement with an electron spin. In this Letter, we report the first realization of single-shot readout for a nuclear spin in SiC. We obtain a deterministic nuclear spin initialization and readout fidelity of 94.95% with a measurement duration of 1 ms. With a dual-step readout scheme, we obtain a readout fidelity as high as 99.03% within 0.28 ms by sacrificing the success efficiency. Our Letter complements the experimental toolbox of harnessing both electron and nuclear spins in SiC for future quantum networks.

A solid-state approach for quantum networks is advantageous, as it allows the integration of nanophotonics to enhance the photon emission and the utilization of weakly coupled nuclear spins for long-lived storage. Silicon carbide, specifically point defects within it, shows great promise in this regard due to the easy of availability and well-established nanofabrication techniques. Despite of remarkable progresses made, achieving spin-photon entanglement remains a crucial aspect to be realized. In this Letter, we experimentally generate entanglement between a silicon vacancy defect in silicon carbide and a scattered single photon in the zero-phonon line. The spin state is measured by detecting photons scattered in the phonon sideband. The photonic qubit is encoded in the time-bin degree of freedom and measured using an unbalanced Mach-Zehnder interferometer. Photonic correlations not only reveal the quality of the entanglement but also verify the deterministic nature of the entanglement creation process. By harnessing two pairs of such spin-photon entanglement, it becomes straightforward to entangle remote quantum nodes at long distance.

It has been revealed that gestational weight gain (GWG) influences the risk of autism spectrum disorder (ASD) in the offspring, but the findings are inconsistent. The current study aimed to evaluate the relationship between GWG and risk of ASD in offspring. Four electronic databases were searched up to August 28 2018 to identify observational studies reporting the association between GWG and risk of ASD in the offspring. Nine studies which met the inclusion criteria were included in the systematic review. Finally, five studies with a total of 3793 children with ASD were included in the meta-analysis. The-results indicated that excessive GWG might increase the risk of ASD in offspring ( p  = .0008, OR  =  1.23, 95% confidence interval (CI) 1.09-1.38). More high quality cohort studies are needed to confirm this result. This research has the potential to inspire new research on ASD and promote efforts to design appropriate interventions against excessive GWG.Impact statement What is already known on this subject? It has been revealed that gestational weight gain (GWG) influences the risk of autism spectrum disorder (ASD) in the offspring, but the findings are inconsistent. What the results of this study add? This is the first systematic review and meta-analysis on the association between GWG and ASDs in offspring. This study suggested that excessive GWG was associated with higher risk of ASD in offspring. What the implications are of these findings for clinical practice and/or further research? More high quality cohort studies are needed to confirm this result. This research has the potential to inspire new research on ASD and promote efforts to design appropriate interventions against excessive GWG.

Dry winter eggs of Artemia salina were treated with a 30-60 mT inhomogeneous constant magnetic field for 113 h, and then carried by Chinese Satellite "8885" to its spaceflight for 8 days. Their early development rate and hatching ratio were observed on the 10th, 31st, 65th and 227th days after the accomplishment of the flight. Three main results were obtained as follows: (i) The treatment accelerated the development of the eggs not flown; (ii) it also enhanced the resistance of the flown eggs against unfavorable spaceflight effects (retarding early development and lowering the hatching ratio), and promoted the recovering ability of the flown eggs from the affected state; and (iii) the latent beneficial effect produced by treatment was found to be very durable, still appearing in the development of the treated eggs on the 318th day after treatment (the 227th day after the flight).

Dry eggs of Artemia salina were exposed to 80 KV-X-rays and Kr-Ions (energy: 11.75 MeV/u; LET: 3500 KeV/microns). Emergence, hatching and survival were determined. The results demonstrate a very high resistance both to sparsely and ionizing radiation.