Analog signal metasurface processor supporting mathematical operator reconfiguration.

Electromagnetic wave analog computing is an effective method to overcome the bottleneck of electronic computing, which has attracted the attention of scientists. However, many spatial analog signal processing systems based on electromagnetic waves can only execute one unique mathematical operator and cannot provide multiple operators for users to choose arbitrarily. In order to enhance the function of the current spatial analog computing system, we design a coding structure with amplitude-phase decoupling modulation to realize the analog signal processor that supports the switching of mathematical operators and demonstrate the precise switching from the first-order spatial differential operator to the first-order spatial integral operator. Our design idea can be used as a paradigm for designing small reconfigurable analog computing systems, paving the way for the construction of high-speed, multifunctional, and universal signal processing systems. This idea can be extended to any other range of waves.

Multispectral camouflage nanostructure design based on a particle swarm optimization algorithm for color camouflage, infrared camouflage, laser stealth, and heat dissipation.

With the development of camouflage technology, single camouflage technology can no longer adapt to existing environments, and multispectral camouflage has attracted much research focus. However, achieving camouflage compatibility across different bands remains challenging. This study proposes a multispectral camouflage metamaterial structure using a particle swarm optimization algorithm, which exhibits multifunctional compatibility in the visible and infrared bands. In the visible band, the light absorption rate of the metamaterial structure exceeds 90%. In addition, color camouflage can be achieved by modifying the top cylindrical nanostructure to display different colors. In the infrared band, the metamaterial structure can achieve three functions: dual-band infrared camouflage (3-5 µm and 8-14 µm), laser stealth (1.06, 1.55, and 10.6 µm), and heat dissipation (5-8 µm). This structure exhibits lower emissivity in both the 3-5-µm (ɛ=0.18) and 8-14-µm (ɛ=0.27) bands, effectively reducing the emissivity in the atmospheric window band. The structure has an absorption rate of 99.7%, 95.5%, and 95% for 1.06, 1.55, and 10.6 µm laser wavelengths, respectively. Owing to its high absorptivity, laser stealth is achieved. Simultaneously, considering the heat dissipation requirements of metamaterial structures, the structural emissivity is 0.7 in the non-atmospheric window (5-8 µm), and the heat can be dissipated through air convection. Therefore, the designed metamaterial structure can be used in military camouflage and industrial applications.

On-Chip Optical Adder and Differential-Equation-Solver Based on Fourier Optics and Metasurface.

Analog optical computing (AOC) has attracted great attention over the past few years, because of its ultra-high speed (potential for real-time processing), ultra-low power consumption, and parallel processing capabilities. In this article, we design an adder and an ordinary differential equation solver (ODE) on chip by Fourier optics and metasurface techniques. The device uses the 4f system consisting of two metalenses on both sides and one middle metasurface (MMS) as the basic structure. The MMS that performs the computing is the core of the device and can be designed for different applications, i.e., the adder and ODE solver in this article. For the adder, through the comparison of the two input and output signals, the effect of the addition can be clearly displayed. For the ODE solver, as a proof-of-concept demonstration, a representative optical signal is well integrated into the desired output distribution. The simulation result fits well with the theoretical expectation, and the similarity coefficient is 98.28%. This solution has the potential to realize more complex and high-speed artificial intelligence computing. Meanwhile, based on the direct-binary-search (DBS) algorithm, we design a signal generator that can achieve power splitting with the phase difference of π between the two output waveguides. The signal generator with the insertion loss of -1.43 dB has an ultra-compact footprint of 3.6 µm× 3.6 µm. It can generate a kind of input signal for experimental verification to replace the hundreds of micrometers of signal generator composed of a multi-mode interference (MMI) combination used in the verification of this type of device in the past.

Psychosocial aspects in myasthenic patients treated by plasmapheresis.

Knowledge about the postintervention psychosocial status of myasthenia gravis (MG) is limited and based on questionnaire studies. In this study, the effects of improvement in muscle strength with plasmapheresis treatment on both quality of life (QoL) and psychological status of MG patients were studied. Between January 2008 and December 2009, 29 MG patients were enrolled to receive one course of plasmapheresis treatment. Differences in baseline and posttherapy clinical, laboratory, and psychosocial measures were determined. The mean MG score decreased from 7.8 points at baseline to 4.2 after plasmapheresis, accompanied by the mean antibody clearance of 56%. Psychosocial tests showed significant pre- and posttherapy differences in illness identity (mean scores 23.62 and 20.79 points, respectively) and disability (mean scores 11.28 and 7.63 points, respectively) (p < 0.01). No significant differences were found for the other indices. Although both anxiety and depression scores did not differ significantly, there was a clear change in patients, as evidenced by their decreases in severity after treatment. The mean mental components scores of QoL were still less than 40 after treatment, indicating that myasthenic patients need assistance in adapting to their disease. Thus, although plasmapheresis treatment achieved immediate improvement of myasthenic symptoms, reduced disability, and better illness identity, both emotional status and QoL did not differ significantly after intervention. Systematical evaluation for patients' illness perceptions and emotional problems are warranted and related strategies should be taken for long-term stabilization of psychosocial function.

Effects of metformin on rosiglitazone-induced cardiac hypertrophy in mice.

Thiazolidinediones (TZD) can cause adipose tissue accumulation and myocardial hypertrophy. This study aimed to determine if combined Metformin (Glucophage) and Rosiglitazone (Avandia) could reduce the risk of heart failure caused by Rosiglitazone in BALB/c mice. BALB/c mice were treated with oral Rosiglitazone/Metformin twice daily for four weeks. Metformin or Rosiglitazone alone and non-treated mice acted as double control. Myocardial hypertrophy and associated side effects of the combined therapy were determined through isolated heart and body weights. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were applied to evaluate expression of sulfonylurea receptor 2A (SUR2A) and Kir 6.2. The activities of peroxisome proliferator activated receptor alpha (PPARalpha) in the myocardium were also observed. Rosiglitazone/Metformin decreased body weight gain and food intake, and inhibited an increasing adipose ratio but did not reduce myocardial hypertrophy. Rosiglitazone increased Kir6.2/SUR2A, Kir6.2/SUR2B, and PPARalpha gene expression. The Rosiglitazone/Metformin combination further increased these gene expressions, especially PPARalpha. Metformin inhibits obesity but has no effect in reducing myocardial hypertrophy caused by Rosiglitazone. Whether Metformin can reduce side effects of TZDs in humans warrants further study.