Research on accurate non-contact temperature measurement method for telescope mirror.

Non-contact temperature measurement for a solar telescope mirror is critical for improving the mirror seeing and thermal deformation of solar telescopes, a long-standing challenge in astronomy. This challenge arises from the telescope mirror's inherent weak thermal radiation, often overwhelmed by reflected background radiations due to its high reflectivity. In this work, an infrared mirror thermometer (IMT) is equipped with a thermally-modulated reflector, and a measurement method based on an equation for extracting mirror radiation (EEMR) has been developed for probing the accurate radiation and temperature of the telescope mirror. Using this approach, we can extract the mirror radiation from the instrumental background radiation via the EEMR. This reflector has been designed to amplify the mirror radiation signal incident on the infrared sensor of IMT, while inhibiting the radiation noise from the ambient environment. In addition, we also propose a set of evaluation methods for IMT performance based on EEMR. The results reveal that the temperature measurement accuracy of IMT to the solar telescope mirror using this measurement method can be achieved better than ±0.15°C.

Study of transient behaviors of wavefront error caused by natural convection for improving mirror seeing.

Astronomical seeing parameters calculated based on the Kolmogorov turbulence model cannot fully evaluate the effect of the natural convection (NC) above a solar telescope mirror on the image quality, as the convective air motions and temperature variations of the NC are significantly different from the Kolmogorov turbulence. In this work, a new method based on the transient behaviors and frequency characteristics of NC-related wavefront error (WFE) are investigated in detail and used to evaluate the image quality degradation caused by a heated telescope mirror, aiming to make up for the deficiency of astronomical seeing parameters with the conventional method in evaluating the image quality degradation. Transient computational fluid dynamics (CFD) simulations and WFE calculations based on discrete sampling and ray segmentation are performed to quantitatively evaluate the transient behaviors of the NC-related WFE. It clearly exhibits apparent oscillatory characteristics, which are coupled by main oscillation with low frequencies and minor oscillation with high frequencies. Moreover, the generation mechanisms of two types of oscillations are studied. The conspicuous oscillation frequencies of the main oscillation caused by heated telescope mirrors with varying dimensions are primarily lower than 1 Hz, suggesting that active optics may be adopted to correct the main oscillation of NC-related WFE while the adaptive optics may correct the minor oscillation. Furthermore, a mathematical relationship between WFE, temperature rise, and mirror diameter is derived, revealing a significant correlation between WFE and mirror diameter. Our work suggests the transient NC-related WFE should be considered as one of the critical supplements to the mirror seeing evaluation.

System-level graphene foam speaker and the simulation of the thermo-acoustic process.

Recent studies have shown that microporous graphene foam (GF) exhibits photoacoustic effect when irradiated with modulated light. Inspired by this phenomenon, we fabricated a light emitting diode (LED)-induced system-level GF speaker that generates photoacoustic waves in a frequency range of 0.2-16 kHz or plays music with high fidelity when illuminated by modulated LED light. LED light modulation is realized by our specially designed driving circuit that combines the AC voltage corresponding to the audio signal (sinusoidal signal or music from a cell phone) and a DC bias. To reveal the effect of the microporous structure of GF on the photoacoustics, we simulated the thermo-acoustic process (the second process of the photoacoustic effect). We built a periodically heated model of micro-spherical air unit with a diameter of 42 µm to investigate the relationship between the heat flow absorbed by the air unit and the thermo-acoustic wave created by it. The simulated results show that in the frequency range of 0.2-16 kHz, the thermo-acoustic pressure correlates with the frequency of heat flow. Moreover, in the diameter range of 10 to 80 µm of the air unit, the thermo-acoustic pressure is directly proportional to the square of the diameter of the air unit, suggesting that the photoacoustic effect can be enhanced by increasing the size of the GF pores to a certain extent. This work demonstrates the light-induced speakers and provides theoretical support for the photoacoustic effect that occurs in materials with microporous structures.

Association Between High-Sensitivity C-Reactive Protein and Prognosis of Patients with Acute Cerebral Infarction.

Purpose: To investigate the association of serum high-sensitivity C-reactive protein (hs-CRP) with the severity of neurological deficits and prognosis in patients with acute cerebral infarction (ACI). Patients and Methods: In this retrospective analysis, 119 patients with ACI were recruited from January to December 2020. The serum hs-CRP level was measured by a latex-enhanced immunoturbidimetric assay. The severity of neurological deficits and prognosis of ACI patients were assessed using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). Multivariate logistic analysis was performed and receiver operating characteristic (ROC) curves were plotted to evaluate the value of hs-CRP in predicting the prognosis of ACI. Results: The patients with a more favorable prognosis (mRS score 0-2) had a lower median serum hs-CRP level than those with a worse prognosis (mRS score 3-6) (3.32 IQR: 1.51, 8.04 to 17.93 IQR:16.02, 19.01; P<0.001). After adjusting for potential confounders, multivariable linear regression showed that serum hs-CRP level was independently associated with NIHSS score (Beta = 0.952, P<0.001) and mRS score (Beta=0.878, P<0.001). Multivariate logistic analysis revealed that high hs-CRP level was an independent predictor of the poor prognosis in patients with ACI (adjusted1 OR = 1.995; 95% CI = 1.499-2.655; adjusted2 OR = 2.75; 95% CI = 1.015-7.457). ROC curve analysis indicated that the area under the curve for hs-CRP to predict poor prognosis was 0.986. The cutoff value, sensitivity, and specificity were 11.835 mg/L, 95%, and 92.5%, respectively. In terms of ischemic stroke subtypes, the serum hs-CRP level was higher in large-artery atherosclerosis (LAA) patients than in those with small-artery occlusion (SAO) and cardioembolism (CE). In addition, the patients with LAA had higher scores of NIHSS and mRS than those with SAO and CE. Conclusion: Serum hs-CRP level is an independent predictor of prognosis, and an efficient index to discriminate patients with ACI, especially for those with LAA.

High-transmission narrowband ultraviolet filter based on an aluminum laminated nanostructure on glass.

We present an aluminum (Al) laminated nanostructure stacked on a glass substrate to produce highly transmitted narrowband ultraviolet (UV) filters. The laminated nanostructure was mainly composed of an Al nanohole array, and each Al nanohole had a coaxial Al nanoring at the bottom. This UV filter showed a single dominant peak with a high transmission over 50% and a narrow bandwidth less than 80 nm in the 200-400 nm waveband that was achieved based on the synergy of surface plasmon resonance (SPR) and localized surface plasmon resonance (LSPR). The electric field profiles of the laminated nanostructure indicate that SPR selects the transmission wavelength and LSPR contributes to single peak. This narrowband UV filter can be utilized in UV detectors.

Clinicopathological and Prognostic Roles of STAT3 and Its Phosphorylation in Glioma.

Glioma is defined as a common brain tumor which causes severe disability or death. As many genes are reported to relate with glioma's occurrence and development, their prognostic and therapeutic value still remains uncertain. This study aimed at investigating the association between STAT3/p-STAT3 and glioma prognosis. Nine studies (12 trials) scored ≥5 on the Newcastle-Ottawa scale were meta-analysed from the Medline, Embase, and Web of Science databases. We found that STAT3/p-STAT3 overexpression in glioma patients was associated with worse overall survival (hazard ratio (HR) = 1.40, 95%confidence interval (CI) = 1.05 ~ 1.86, P = 0.020), progression-free survival (HR = 2.05, 95%CI = 1.63 ~ 2.58, P < 0.001), and better recurrence-free survival (HR = 0.37, 95%CI = 0.15 ~ 0.95, P < 0.039). Subgroup analysis implied that STAT3/p-STAT3 overexpression was associated with worse OS in standard treatment (HR = 1.80, 95%CI = 1.06 ~ 3.04, P = 0.030), and in China (HR = 2.18, 95%CI = 1.77 ~ 2.70, P < 0.001), and metaregression analysis indicated countries (P = 0.001) may be the source of heterogeneity in our study. In conclusion, we suggested STAT3/p-STAT3 was associated with poor prognosis in patients with glioma, which indicated that STAT3/p-STAT3 might be a valuable prognostic biomarker and a promising therapeutic target for glioma.

Broadband perovskite quantum dot spectrometer beyond human visual resolution.

The quantum dot spectrometer, fabricated by integrating different quantum dots with an image sensor to reconstruct the target spectrum from spectral-coupled measurements, is an emerging and promising hyperspectrometry technology with high resolution and a compact size. The spectral resolution and spectral range of quantum dot spectrometers have been limited by the spectral variety of the available quantum dots and the robustness of algorithmic reconstruction. Moreover, the spectrometer integration of quantum dots also suffers from inherent photoluminescence emission and poor batch-to-batch repeatability. In this work, we developed nonemissive in situ fabricated MA3Bi2X9 and Cs2SnX6 (MA = CH3NH3; X = Cl, Br, I) perovskite-quantum-dot-embedded films (PQDFs) with precisely tunable transmittance spectra for quantum dot spectrometer applications. The resulting PQDFs contain in situ fabricated perovskite nanocrystals with homogenous dispersion in a polymeric matrix, giving them advantageous features such as high transmittance efficiency and good batch-to-batch repeatability. By integrating a filter array of 361 kinds of PQDFs with a silicon-based photodetector array, we successfully demonstrated the construction of a perovskite quantum dot spectrometer combined with a compressive-sensing-based total-variation optimization algorithm. A spectral resolution of ~1.6 nm was achieved in the broadband of 250-1000 nm. The performance of the perovskite quantum dot spectrometer is well beyond that of human eyes in terms of both the spectral range and spectral resolution. This advancement will not only pave the way for using quantum dot spectrometers for practical applications but also significantly impact the development of artificial intelligence products, clinical treatment equipment, scientific instruments, etc.

Performance analysis of PQDCF-coated silicon image sensor using Monte-Carlo ray-trace simulation.

Perovskite quantum dots embedded composite film (PQDCF) exhibits strong photoluminescence emissions and is expected to be excellent down-shifting material for enhancing ultraviolet (UV) response of silicon devices. In this work, light conversion process is analyzed by combining the experiments with Monte-Carlo ray-trace simulation. Results show that external quantum efficiency (EQE) in the UV region was mainly determined by absorption loss and match of peak wavelength. Moreover, resolution was correlated with thickness and reabsorption. This conclusion provides a guideline for designing novel materials with enhanced UV sensitivity and an EQE of 28% is predicted. Our experimental results showed that the use of red emissive PQDCF achieved an EQE of 20%.

Archimedean spiral push-broom differential thermal imaging for gas leakage detection.

An uncooled infrared focal plane array (FPA) for a multiband optical imaging system monitoring small gas leakages is low in cost but limited by its frame rate and sensitivity. We propose the concept of Archimedean spiral push-broom filtering (ASPBF), where the trajectory of an Archimedean spiral over the FPA is approximated as a straight line. The ASPBF precisely matches the electronic pulse scanning of the uncooled infrared FPA row by row to improve the frame rate. We applied differential imaging to promote gas detection sensitivity. Prototype can detect 11 ml/min of ethylene gas at ΔT = 3 °C with frame rate of 8 fps.

Highly luminescent red emissive perovskite quantum dots-embedded composite films: ligands capping and caesium doping-controlled crystallization process.

Perovskite quantum dots (PQDs) are emerging as functional luminescence down-shifting materials for light conversion applications. The incorporation of PQDs into a polymeric matrix is a key step to improving their stability, thus facilitating device integration. Compared to the conventional way of mixing the pre-synthesized PQDs into a polymer, the in situ fabrication of perovskite quantum dots-embedded composite films (PQDCFs) is an efficient and cost-effective method, which yields enhanced photoluminescence properties. This method has been successfully developed for green emissive CH3NH3PbBr3 PQDCFs, whereas the red CH3NH3PbI3 PQDCFs only show the photoluminescence quantum yields (PLQYs) less than 15%. By means of combining transmittance electron microscopy (TEM) and absorption spectrum analysis, we showed that the "perovskite red wall" in PQDCFs was mainly related to the phase separation, formation of large-sized particles and incomplete chemical conversion of precursors. These problems are caused by the solubility variance of perovskite precursors in the solvent as well as the solvation compatibility between perovskite precursors and the polymer during the crystallization process. Based on these findings, we introduced Cs+ as a dopant and 3,3-diphenylpropyamine (DPPA) as capping ligands, respectively, to decrease the solubility variance of the precursors and improve the compatibility between PQDs and the polymer. Consequently, highly luminescent red emissive PQDCFs with a PLQY of 91% were achieved with this strategy.

Efficient Light-Emitting Diodes Based on in Situ Fabricated FAPbBr3 Nanocrystals: The Enhancing Role of the Ligand-Assisted Reprecipitation Process.

In this paper, we reported the in situ fabrication of highly luminescent formamidinium lead bromide (FAPbBr3) nanocrystal thin films by dropping toluene as an anti-solvent during the spin-coating with a perovskite precursor solution using 3,3-diphenylpropylamine bromide (DPPA-Br) as a ligand. The resulting films are uniform and composed of 5-20 nm FAPbBr3 perovskite nanocrystals. By monitoring the solvent mixing of anti-solvent and precursor solution on the substrates, we illustrated the difference between the ligand-assisted reprecipitation (LARP) process and the nanocrystal-pinning (NCP) process. This understanding provides a guideline for film optimization, and the optimized films obtained through the in situ LARP process exhibit strong photoluminescence emission at 528 nm, with quantum yields up to 78% and an average photoluminescence lifetime of 12.7 ns. In addition, an exciton binding energy of 57.5 meV was derived from the temperature-dependent photoluminescence measurement. More importantly, we achieved highly efficient pure green perovskite based light-emitting diode (PeLEDs) devices with an average external quantum efficiency (EQE) of 7.3% (maximum EQE is 16.3%) and an average current efficiency (CE) of 29.5 cd A-1 (maximum CE is 66.3 cd A-1) by adapting a conventional device structure of ITO/PEDOT:PSS/TFB/perovskite film/TPBi/LiF/Al. It is expected that the in situ LARP process provides an effective methodology for the improvement of the performance of PeLEDs.

Monocular catadioptric panoramic depth estimation via caustics-based virtual scene transition.

Existing catadioptric panoramic depth estimation systems usually require two panoramic imaging subsystems to achieve binocular disparity. The system structures are complicated and only sparse depth maps can be obtained. We present a novel monocular catadioptric panoramic depth estimation method that achieves dense depth maps of panoramic scenes using a single unmodified conventional catadioptric panoramic imaging system. Caustics model the reflection of the curved mirror and establish the distance relationship between the virtual and real panoramic scenes to overcome the nonlinear problem of the curved mirror. Virtual scene depth is then obtained by applying our structure classification regularization to depth from defocus. Finally, real panoramic scene depth is recovered using the distance relationship. Our method's effectiveness is demonstrated in experiments.

A phosphotyrosine switch determines the antitumor activity of ERß.

Estrogen receptors ERα and ERß share considerable sequence homology yet exert opposite effects on breast cancer cell proliferation. While the proliferative role of ERα in breast tumors is well characterized, it is not clear whether the antitumor activity of ERß can be mobilized in breast cancer cells. Here, we have shown that phosphorylation of a tyrosine residue (Y36) present in ERß, but not in ERα, dictates ERß-specific activation of transcription and is required for ERß-dependent inhibition of cancer cell growth in culture and in murine xenografts. Additionally, the c-ABL tyrosine kinase and EYA2 phosphatase directly and diametrically controlled the phosphorylation status of Y36 and subsequent ERß function. A nonphosphorylatable, transcriptionally active ERß mutant retained antitumor activity but circumvented control by upstream regulators. Phosphorylation of Y36 was required for ERß-mediated coactivator recruitment to ERß target promoters. In human breast cancer samples, elevated phosphorylation of Y36 in ERß correlated with high levels of c-ABL but low EYA2 levels. Furthermore, compared with total ERß, the presence of phosphorylated Y36-specific ERß was strongly associated with both disease-free and overall survival in patients with stage II and III disease. Together, these data identify a signaling circuitry that regulates ERß-specific antitumor activity and has potential as both a prognostic tool and a molecular target for cancer therapy.

[Perceptual sharpness metric for visible and infrared color fusion images].

For visible and infrared color fusion images, objective sharpness assessment model is proposed to measure the clarity of detail and edge definition of the fusion image. Firstly, the contrast sensitivity functions (CSF) of the human visual system is used to reduce insensitive frequency components under certain viewing conditions. Secondly, perceptual contrast model, which takes human luminance masking effect into account, is proposed based on local band-limited contrast model. Finally, the perceptual contrast is calculated in the region of interest (contains image details and edges) in the fusion image to evaluate image perceptual sharpness. Experimental results show that the proposed perceptual sharpness metrics provides better predictions, which are more closely matched to human perceptual evaluations, than five existing sharpness (blur) metrics for color images. The proposed perceptual sharpness metrics can evaluate the perceptual sharpness for color fusion images effectively.

[Prokaryotic expression and purification of human histone-1 and its activity detection].

AIM: To construct the prokaryotic expression vector of human histone-1, obtain the purified GST-H1 protein, and detect its activity. METHODS: Human histone-1 coding region was amplified from human mammary cDNA library, and was inserted into prokaryotic expression vector pGEX-KG. The recombinant plasmid pGEX-KG-H1 was transformed into E.coli Rossate. The expressed product was purified by GST-Sepharose 4B beads and identified by SDS-PAGE and Western blot analysis. RESULTS: The DNA fragment of about 650 bp was successfully amplified by PCR, cloned into pGEX-KG, and identified by sequencing. The recombinant protein of about M(r); 52 000 was successfully induced, purified and tested well by Kinase assay. CONCLUSION: The recombinant protein of GST-H1 is obtained successfully, which lay the foundation for further research on cell cycle control.

[Construction of human Egr-1 promoter and its response to ionizing radiation in tumor cells].

AIM: To construct human Egr-1 promoter luciferase reporter system and study its activity induced by ionizing radiation. METHODS: Egr-1 promoter was obtained by human genomic PCR and cloned into pGL3-basic vector. After transfection of recombinant plasmid into human tumor cells, the Egr-1 promoter activity induced by ionizing radiation was detected by luciferase reporter assay. RESULTS: The luciferase reporter system of Egr-1 promoter was successfully constructed. The activity of Egr-1 promoter was substantially increased after different doses of IR and reached to the peak at the time point of 48 h after IR. CONCLUSION: The Egr-1 promoter was constructed in this study showed IR inducible activity in tumor cells, laying foundation for the research of radiation. mediated gene therapy.