Research on key technology of cooled infrared bionic compound eye camera based on small lens array.

Traditional 2D imaging technologies are limited by the need for a large field of view and their sensitivity to small target motion. Inspired by the characteristics of insect compound eye structure, we propose an infrared bionic compound eye camera based on a small lens array. The camera is composed of 61 small lens arrays mounted on a curved spherical shell and a relay optical system. The imaging device is a high-performance cooled mid-wave infrared detector. This is an innovative design for an infrared biomimetic compound eye camera system that provides a wide field of view and all-day detection capability. Aimed to meet the specified requirements. The optical system achieves a 100% cold-membrane match between the infrared optical system and the cooled detector, and the relay optical system optimizes the large-field aberration by introducing a higher-order aspheric surface and modifying the geometric surface of the lenses. Our entire system enables an observation field angle of 108 ∘ × 108 ∘ . The experiments showed that the image quality of the system is high, each ommatidium was effective within the imaging range of the compound eye camera, resulting in an improved signal-to-noise ratio in various scenes.

[Effect of transcutaneous acupoint electrical stimulation at Neiguan (PC 6) on general anesthesia under preserving spontaneous breathing in thoracoscopic lobectomy].

OBJECTIVE: To evaluate the effect of transcutaneous acupoint electrical stimulation (TEAS) at Neiguan (PC 6) on general anesthesia under preserving spontaneous breathing in thoracoscopic lobectomy. METHODS: A total of 66 patients of primary lung cancer undergoing thoracoscopic lobectomy were divided to an observation group (33 cases, 1 case discontinued) and a control group (33 cases). In the observation group, TEAS at Neiguan (PC 6) was used 30 min before anesthesia induction till the end of surgery. The surgery time, maximum value of partial pressure of end-tidal carbon dioxide (PETCO2) and minimum value of oxygen saturation (SpO2) of the two groups were recorded. The dosage of propofol, sufentanil, remifentanil and dexmedetomidine were analyzed. Separately, before induction (T0), at the start of surgery (T1), thoracic exploration (T2) and lobectomy (T3), as well as 30 min (T4) and 60 min (T5) after lobectomy, the mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), serum cortisol (Cor) and norepinephrine (NE) were measured. The time of post anesthesia care unit (PACU) stay, ambulation, flatus, chest drainage and the incidence of nausea and vomiting were compared between the two groups. RESULTS: The maximum value of PETCO2, the dosage of propofol and remifentanil in the observation group were lower than those in the control group (P < 0.05, P < 0.01), the minimum value of SpO2 in the observation group was higher than that of the control group (P < 0.01). At T1-T5, the MAP, HR, serum Cor and NE levels in the observation group were all lower than those in the control group (P < 0.05). The ambulation time, the time for the flatus, chest drainage time, and the incidence of nausea and vomiting in the observation group were all lower than those in the control group (P<0.001, P < 0.01). CONCLUSION: For the general anesthesia under preserving spontaneous breathing in thoracoscopic surgery, TEAS at Neiguan (PC 6) relieves stress response, reduces opioids dosage and promotes postoperative recovery.

[Effect of electroacupuncture at Neiguan (PC 6) on pulmonary function during one-lung ventilation in patients with lobectomy].

OBJECTIVE: To observe the protective effect of electroacupuncture (EA) at Neiguan (PC 6) on pulmonary function during one-lung ventilation (OLV) in patients with lobectomy, and explore its action mechanism. METHODS: Sixty patients with lobectomy were randomly divided into an observation group and a control group, 30 cases in each one. The patients in the control group were treated with general anesthesia, and OLV was given when surgery began; when the surgery finished, air was removed from the thoracic cavity and two-lung ventilation was performed. On the basis of the treatment in the control group, the patients in the observation group were treated with EA (disperse-dense wave, 2 Hz/100 Hz of frequency) at Neiguan (PC 6) 30 min before anesthesia induction until the end of the surgery. The pulmonary function indexes [arterial partial pressure of oxygen (PaO2), oxygenation index (OI), compliance of lung (CL), respiratory index (RI)] and serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were observed before surgery (T0), 30 min into OLV (T1), 60 min into OLV (T2) and after operation (T3). The total incidence of complications, pressing times of postoperative patient-controlled analgesia pump in 48 h after surgery and hospital stay were compared between the two groups. RESULTS: Compared with T0, the PaO2, OI, CL and serum SOD at T1, T2 and T3 in the two groups were decreased (P<0.05), and those in the observation group were higher than those in the control group (P<0.05). The RI and serum levels of MDA, IL-6, TNF-α at T1, T2 and T3 in the two groups were increased, and those in the observation group were lower than those in the control group (P<0.05). The total incidence of complications in the observation group was lower than that in the control group [3.3% (1/30) vs 23.3% (7/30), P<0.05]. The pressing times of postoperative patient-controlled analgesia pump in 48 h after surgery and hospital stay in the observation group were less than those in the control group (P<0.05). CONCLUSION: EA at Neiguan (PC 6) has protective effects on lung injury induced by OLV after lobectomy, and its mechanism may be related to the improvement of oxidative stress and inflammatory response.

Evolution of dissolved organic matter during artificial groundwater recharge with effluent from underutilized WWTP and the resulting facilitated transport effect.

Currently, the interaction between contaminants and dissolved organic matter (DOM) during artificial groundwater recharge (AGR) with effluent from underutilized wastewater treatment plant (WWTP) is unclear. The present study investigated DOM evolution in this AGR scenario. The DOM composition in the inflow was identified to be distinct to that of the outflow due to the release of soil humic acid (HA). The soluble soil HA was then extracted and used in co-transport experiments with tetracycline (TC). The separated HA transport through the soil column exhibited high mobility with mass recovery >92.5% in the effluent. Following the mixing of injected TC and HA, the TC breakthrough in the column increased with HA concentration. TC was heavily adsorbed by the soil without the presence of HA, yet the retention ratios decreased from 63.60% to 53.30% for the HA range of 0-20 mg L-1. An advection-dispersion-retention (ADR) numerical model was developed to effectively quantify the HA-TC co-transport, with results demonstrating the reduction in the TC attachment rate with increasing HA concentrations. Furthermore, batch adsorption experiments, kinetics and isotherms models, and FTIR spectra analysis were implemented to determine the underlying mechanism. The co-transport behavior was observed to be a function of the relative soil sorption affinity between HA and TC. The weaker sorption of the HA-coated TC compared to the separated TC consequently suggests that HA is likely to compete for available soil adsorption sites. Thus, the release of soil humus during AGR can potentially facilitate the transport of the introduced contaminants.

Enhancing photoluminescence of carbon quantum dots doped PVA films with randomly dispersed silica microspheres.

As a kind of excellent photoluminescent material, carbon quantum dots have been extensively studied in many fields, including biomedical applications and optoelectronic devices. They have been dispersed in polymer matrices to form luminescent films which can be used in LEDs, displays, sensors, etc. Owing to the total internal reflection at the flat polymer/air interfaces, a significant portion of the emitted light are trapped and dissipated. In this paper, we fabricate free standing flexible PVA films with photoluminescent carbon quantum dots embedded in them. We disperse silica microspheres at the film surfaces to couple out the total internal reflection. The effects of sphere densities and diameters on the enhancement of photoluminescence are experimentally investigated with a homemade microscope. The enhancement of fluorescence intensity is as high as 1.83 when the film is fully covered by spheres of 0.86 [Formula: see text]m diameter. It is worth noting that the light extraction originates from rather the scattering of individual spheres than the diffraction of ordered arrays. The mechanism of scattering is confirmed by numerical simulations. The simulated results show that the evanescent wave at the flat PVA/air interface can be effectively scattered out of the film.

Fabrication of broadband anti-reflective layers by mask-free etching TiO2 films.

We present a simple way to make TiO2 anti-reflective layers on top of silicon substrates. Surfaces of TiO2 films have been modified by radio frequency plasma with CF4 as an etchant. Mask-free etching process on the polycrystalline films leads to the formation of random sub-wavelength textures. The reflection of the etched samples are significantly suppressed in the wavelength range of 400~800 nm (2.9~4.6%, 3% compared with 34% on bare silicon at the wavelength of 600 nm). We have numerically simulated the optical properties of TiO2 layers using the finite-difference time-domain method. The anti-reflective effects are attributed to random roughness on TiO2 surfaces. The etching porcess increases the surface roughness, therefore, the gradient of refractive index between air and silicon substrate is reduced. As a result, the Fresnel reflection is supressed. Our results demonstrate an efficient way of anti-reflective coating for solar cells.