Complex-valued neural networks have many advantages over their real-valued counterparts. Conventional digital electronic computing platforms are incapable of executing truly complex-valued ...representations and operations. In contrast, optical computing platforms that encode information in both phase and magnitude can execute complex arithmetic by optical interference, offering significantly enhanced computational speed and energy efficiency. However, to date, most demonstrations of optical neural networks still only utilize conventional real-valued frameworks that are designed for digital computers, forfeiting many of the advantages of optical computing such as efficient complex-valued operations. In this article, we highlight an optical neural chip (ONC) that implements truly complex-valued neural networks. We benchmark the performance of our complex-valued ONC in four settings: simple Boolean tasks, species classification of an Iris dataset, classifying nonlinear datasets (Circle and Spiral), and handwriting recognition. Strong learning capabilities (i.e., high accuracy, fast convergence and the capability to construct nonlinear decision boundaries) are achieved by our complex-valued ONC compared to its real-valued counterpart.
Physical activity has been shown to suppress tumor initiation and progression. The neurotransmitter dopamine (DA) is closely related to movement and exhibits antitumor properties. However, whether ...the suppressive effects of physical activity on tumors was mediated by the nervous system via increased DA level remains unknowns. Here we show that regular moderate swimming (8 min/day, 9 weeks) raised DA levels in the prefrontal cortex, serum and tumor tissue, suppressed growth, reduced lung metastasis of transplanted liver cancer, and prolonged survival in a C57BL/6 mouse model, while overload swimming (16 and 32 min/day, 9 weeks) had the opposite effect. In nude mice that were orthotopically implanted with human liver cancer cell lines, DA treatment significantly suppressed growth and lung metastasis by acting on the D2 receptor (DR2). Furthermore, DR2 blockade attenuated the suppressive effect of moderate swimming on liver cancer. Both moderate swimming and DA treatment suppressed the transforming growth factor-beta (TGF-β1)-induced epithelial-mesenchymal transition of transplanted liver cancer cells. At the molecular level, DR2 signaling inhibited extracellular signal-regulated kinase phosphorylation and expression of TGF-β1 in vitro. Together, these findings demonstrated a novel mechanism by which the moderate exercise suppressed liver cancer through boosting DR2 activity, while overload exercise had the opposite effect, highlighting the possible importance of the dopaminergic system in tumor growth and metastasis of liver cancer.
Particle trapping and binding in optical potential wells provide a versatile platform for various biomedical applications. However, implementation systems to study multi-particle contact interactions ...in an optical lattice remain rare. By configuring an optofluidic lattice, we demonstrate the precise control of particle interactions and functions such as controlling aggregation and multi-hopping. The mean residence time of a single particle is found considerably reduced from 7 s, as predicted by Kramer's theory, to 0.6 s, owing to the mechanical interactions among aggregated particles. The optofluidic lattice also enables single-bacteria-level screening of biological binding agents such as antibodies through particle-enabled bacteria hopping. The binding efficiency of antibodies could be determined directly, selectively, quantitatively and efficiently. This work enriches the fundamental mechanisms of particle kinetics and offers new possibilities for probing and utilising unprecedented biomolecule interactions at single-bacteria level.
Quantum key distribution (QKD) is a quantum communication technology that promises unconditional communication security. High-performance and cost-effective QKD systems are essential for the ...establishment of quantum communication networks1–3. By integrating all the optical components (except the laser source) on a silicon photonic chip, we have realized a stable, miniaturized and low-cost system for continuous-variable QKD (CV-QKD) that is compatible with the existing fibre optical communication infrastructure4. Here, the integrated silicon photonic chip is demonstrated for CV-QKD. It implements the widely studied Gaussian-modulated coherent state protocol that encodes continuous distributed information on the quadrature of laser light5,6. Our proof-of-principle chip-based CV-QKD system is capable of producing a secret key rate of 0.14 kbps (under collective attack) over a simulated distance of 100 km in fibre, offering new possibilities for low-cost, scalable and portable quantum networks.
Large-scale, highly integrated and low-power-consuming hardware is becoming progressively more important for realizing optical neural networks (ONNs) capable of advanced optical computing. ...Traditional experimental implementations need N
units such as Mach-Zehnder interferometers (MZIs) for an input dimension N to realize typical computing operations (convolutions and matrix multiplication), resulting in limited scalability and consuming excessive power. Here, we propose the integrated diffractive optical network for implementing parallel Fourier transforms, convolution operations and application-specific optical computing using two ultracompact diffractive cells (Fourier transform operation) and only N MZIs. The footprint and energy consumption scales linearly with the input data dimension, instead of the quadratic scaling in the traditional ONN framework. A ~10-fold reduction in both footprint and energy consumption, as well as equal high accuracy with previous MZI-based ONNs was experimentally achieved for computations performed on the MNIST and Fashion-MNIST datasets. The integrated diffractive optical network (IDNN) chip demonstrates a promising avenue towards scalable and low-power-consumption optical computational chips for optical-artificial-intelligence.
► The amorphous Mg11Y2Ni2 alloy undergoes two crystallization steps. ► The crystalline Mg11Y2Ni2 is formed as a metastable phase at first step. ► The stable alloy consists of Mg, YMgNi4 and (Y, Mg) ...solid solution. ► The amorphous and metastable alloys have almost same hydrogen storage kinetics. ► The stable alloy has slightly slower hydrogen storage kinetics.
The crystallization behavior and hydrogen storage kinetics of the amorphous Mg11Y2Ni2 alloy prepared by melt-spinning technique were investigated in detail. It was found that the amorphous Mg11Y2Ni2 alloy transforms into the crystalline Mg11Y2Ni2 in metastable state at 279°C and subsequently decomposes into Mg, YMgNi4 and Y(Mg) solid solution in stable state at 366°C. All the amorphous, metastable and stable Mg11Y2Ni2 alloys can be hydrogenated into MgH2, Mg2NiH4 and YH2/YH3. However, the stable Mg11Y2Ni2 alloy has slightly slower hydrogen absorption–desorption kinetics due to the worse dispersivity of YH2/YH3 and Mg2NiH4.
•P-milling solves the kinetic and synthetic problems of Mg(In) simultaneously.•Mg(In) solid solution catalyzed with in situ formed MgF2 is prepared.•Mg(In) solid solution shows improved desorption ...kinetics (Ea=127.7kJ/mol).•Dual tuning of the thermodynamic and kinetic properties of MgH2 is realized.
The reversible formation of Mg(In) solid solution provides a new way to tune the dehydriding thermodynamics of MgH2. However, the preparation of this solid solution is quite difficult and its dehydriding kinetics is rather sluggish. This work offers a novel technique, plasma milling (P-milling), to solve the two problems simultaneously. The efficiency of the synthesis of Mg(In) solid solution, with a hydrogen capacity of up to 5.16wt.%, is improved significantly. Meanwhile, the kinetics is also modified by the catalyzing effect of in situ synthesized MgF2.
Polarization is an important property of electromagnetic (EM) wave and different polarization manipulations are required for varied optical applications. Here we report a reconfigurable metasurface ...which achieves both the polarization conversion and the polarization rotation in THz regime. The metasurface is reconfigured through the micro-electro-mechanical-systems (MEMS) actuation. The cross polarization transmittance from a linear polarized incidence is experimentally tuned from 0 to 28% at 2.66 THz. In addition, the polarization rotation angle is effectively changed from -12.8° to 13.1° at 1.78 THz. The tunable bi-functional metasurface for polarization conversion and the polarization rotation can be flexibly applied in various applications such as imaging, polarization microscopy and material analysis, etc.
Mg2In0.1Ni solid solution with an Mg2Ni-type structure has been synthesized and its hydrogen storage properties have been investigated. The results showed that the introduction of In into Mg2Ni not ...only significantly improved the dehydrogenation kinetics but also greatly lowered the thermodynamic stability. The dehydrogenation activation energy (Ea) and enthalpy change (ΔH) decreased from 80 kJ/mol and 64.5 kJ/mol H2 to 28.9 kJ/mol and 38.4 kJ/mol H2, respectively. The obtained results point to a method for improving not only the thermodynamic but also the kinetic properties of hydrogen storage materials.
•Mg2In0.1Ni solid solution with an Mg2Ni-type structure is prepared.•Mg2Ni is thermodynamically destabilized by addition of In.•Mg2In0.1Ni solid solution shows excellent desorption kinetics.•Mechanisms of the tuned thermodynamic and kinetic properties are explained.•Dual tuning of the thermodynamic and kinetic properties is realized.
Summary
In this study, we aimed at investigating the impact of melatonin supplementation on semen parameters, hormonal profile and total antioxidant capacity after varicocelectomy. Infertile male ...patients who were diagnosed with varicocele and underwent subinguinal varicocelectomy were included in the study. After performing subinguinal varicocelectomy, the patients were randomised into two groups: 27 receiving melatonin for 3 months and 27 as the placebo‐controlled group receiving placebo for 3 months. The pre‐operative parameters of semen analyses, hormonal profile and seminal oxidative stress status of both groups were compared with those of post‐operative parameters. There were statistically significant improvements in post‐operative parameters of semen analyses (sperm concentration, motility and proportions of normally formed spermatozoa), peripheral blood inhibin B and total antioxidant capacity in melatonin group compared with placebo group. In conclusion, melatonin therapy adds extra benefit to varicecelectomy in terms of sperm parameters, peripheral blood inhibin B and total antioxidant capacity; however, further studies including large number of samples are needed to make a proper decision on melatonin supplementation after varicocelectomy.
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