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Non-uniform low-light images, characterized by complex lighting conditions, pose a significant challenge in image restoration and enhancement, particularly under backlit scenarios where the high-brightness background obscures the foreground information. Existing methods struggle with the diverse illumination factors across different scenes. To overcome this, we introduce a novel deep reconstruction network designed specifically for enhancing non-uniform low-light images. This network leverages the feature representation of uniform natural images, employing the dark channel of the absorption light scattering model (ALSM) to estimate and enhance facial features. Furthermore, the reconstruction process is optimized through the posterior constraint of uniform image characteristics, leading to superior detail enhancement. Our approach has been rigorously tested on both synthetic and real-world images, demonstrating its effectiveness in addressing the complexities of non-uniform low-light image enhancement. The results illustrate a notable enhancement, boosting PSNR by 3.37dB and SSIM by 0.0579 compared to recent methods, with a particular focus on enhancing facial feature details. The code link is https://github.com/zbysygdsghh/face-relight.

Being an important semiconductor material for high power applications, silicon carbide (SiC) faces the problems while used as a gate oxygen layer in traditional Si MOS devices. In view of this, an innovative approach was adopted in the present work to replace the conventional SiO _2 with a high-k material (ZrO _2 ) as the gate oxygen layer to investigate its effect on the electrical characteristics of the devices. In particular ZrO _2 films were deposited on Si and SiC substrates by atomic layer deposition (ALD), and Al was used as the electrode. The atomic force microscopy (AFM) microregion scan revealed a highly flat surface with R _q < 1 nm after the ALD growth of ZrO _2 layer. The sample surface analysis via x-ray photoelectron spectroscopy (XPS) suggested the presence of a small amount of ZrO _x components. According to the electron energy loss spectrum (EELS), the band gap width (E _g ) of this ALD ZrO _2 dielectric was 5.45 eV, which met the requirements for high-quality 4H-SiC-related MOS devices. The electrical properties of the samples were then studied, and the maximum breakdown voltage of the Al/ZrO _2 /SiC/Al MOS structure was obtained to be 23 V, i.e., nearly twice that of the Si substrate. As for the oxide layer, the interface defect density (D _it ) near the conduction band of the Al/ZrO _2 /SiC/Al MOS structure was only 10 ^12 eV ^−1 cm ^−2 orders of magnitude. The N _eff value (the movable charge) of the structure was also controlled at 10 ^12 cm ^−2 . Therefore, the overall performance of the ZrO _2 /SiC structure in terms of electrical properties exceeded that of the ZrO _2 /Si structure and previously reported counterparts. In this respect, the ZrO _2 /SiC MOS capacitor structure has great research potential.

For the first time, this research addresses the notable layout proximity effects induced by stress memorization technique in planer high-k/Metal gate NMOS device systematically, including width effect, different shallow trench spacing effect, and length of diffusion effect. Based on the oxygen diffusion mechanism analysis of layout proximity effects in high-k/Metal gate NMOS device, an optimized process is proposed to suppress the layout dependency. The experiment result indicates that modified low temperature stress memorization technique process can suppress layout dependency efficiently without performance degradation of the devices.

In this work, Sn-doped Ga2O3 films fabricated using plasma-enhanced atomic layer deposition were treated by rapid thermal annealing (RTA). The RTA influence on the chemical state, surface morphology, energy band alignment, and electrical properties of Sn-doped Ga2O3 films were thoroughly investigated. The results of X-ray photoelectron spectroscopy (XPS) demonstrated that Sn atoms were successfully doped into these films. Moreover, energy band alignments were obtained by the energy-loss peak of the O 1s spectrum and valence band spectra and thoroughly discussed. X-ray reflectivity (XRR) and atomic force microscope (AFM) measurements indicated that the Sn-doping level affects the interfacial microstructure and surface morphology. As the Sn content increases, the film thickness decreases while the roughness increases. Finally, the leakage current-voltage (I-V) characteristics proved that the Sn-doped Ga2O3 films have a large breakdown field. In I-V tests, all metal oxide semiconductor (MOS) capacitors exhibited a hard breakdown. This research demonstrates a method for manufacturing high-performance optoelectronic devices with desired properties.

Harmful algal blooms formed by the haptophyte Phaeocystis globosa have been recorded in the Beibu Gulf since 2011. In this study, the composition and variation of phytoplankton assemblages in the Beibu Gulf were studied during an intense bloom of P. globosa from 2016 to 2017, using the CHEMTAX approach. In phytoplankton samples collected from the Beibu Gulf, chlorophyll a (Chl a, 0.046–2.87 μg L−1) and fucoxanthin (Fuco, 0.041–13.7 μg L−1) were the most abundant pigments. Diatoms were the dominant group of phytoplankton, followed by cyanobacteria (mainly Synechococcus), haptophytes, cryptophytes, prasinophytes, dinoflagellates, and chlorophytes. Phytoplankton samples were clustered into four communities characterized by diatoms, cyanobacteria, haptophytes containing 19′-butanoyloxyfucoxanthin (the “Hapt-But” subgroup of haptophytes), and haptophytes containing 19'-hexanoyloxyfucoxanthin (the “Hapt-Hex” subgroup of haptophytes). Distribution pattern of the “Hapt-But” subgroup of haptophyte was consistent with that of P. globosa colonies. Diatoms had positive correlation with P. globosa colony abundance, while cyanobacteria had negative correlation. The diagnostic pigments for colony-forming P. globosa (But-fuco), diatoms (Fuco) and cyanobacteria (zeaxanthin), as well as temperature (

In this work, the atomic level doping of Sn into Ga2O3 films was successfully deposited by using a plasma-enhanced atomic layer deposition method. Here, we systematically studied the changes in the chemical state, microstructure evolution, optical properties, energy band alignment, and electrical properties for various configurations of the Sn-doped Ga2O3 films. The results indicated that all the films have high transparency with an average transmittance of above 90% over ultraviolet and visible light wavelengths. X-ray reflectivity and spectroscopic ellipsometry measurement indicated that the Sn doping level affects the density, refractive index, and extinction coefficient. In particular, the chemical microstructure and energy band structure for the Sn-doped Ga2O3 films were analyzed and discussed in detail. With an increase in the Sn content, the ratio of Sn–O bonding increases, but by contrast, the proportion of the oxygen vacancies decreases. The reduction in the oxygen vacancy content leads to an increase in the valence band maximum, but the energy bandgap decreases from 4.73 to 4.31 eV. Moreover, with the increase in Sn content, the breakdown mode transformed the hard breakdown into the soft breakdown. The C-V characteristics proved that the Sn-doped Ga2O3 films have large permittivity. These studies offer a foundation and a systematical analysis for assisting the design and application of Ga2O3 film-based transparent devices.

Chronic rejection limits the long-term success of cardiac transplantation and the underlying cause of the disease is unknown. Connective tissue growth factor (CTGF) is considered as a mitogenic and chemotactic factor for fibroblasts, and is associated with cell proliferation and collagen synthesis. We evaluated the expression of CTGF in a rat model of heart allograft chronic rejection. Methods: Intra-abdominal heterotopic heart transplantation was performed from 20 Wistar rats to 20 Sprague–Dawley (SD) rats that received cyclosporine, mycophenolate mofetil and methylprednisolone as immunosuppression. Ten heart allografts were explanted at 2 and 8 weeks postoperatively for analysis of morphologic changes. The hearts from 10 normal Wistar rats served as a control group. Coronary artery density, luminal loss of myocardial coronary arteries, and myocardial fibrosis were measured. The expression of CTGF was studied by immunohistochemistry. Correlation between CTGF expression and development of cardiac allograft vasculopathy (CAV) or fibrosis was studied. Results: Allografts harvested at 8 weeks postoperatively showed more coronary intimal proliferation, fibrosis and CTGF expression compared with the 2-week allografts (p < 0.05) and the controls (p < 0.01), but the coronary artery density was lower than in the control group (p < 0.05). However, the control group showed negligible CTGF expression. There were strong negative correlations between the gray value of CTGF protein expression and cardiac fibrosis and coronary intimal occlusion (r = −0.734, −0.713; p < 0.01), which demonstrated that CTGF protein expression was positively correlated with cardiac fibrosis and coronary intimal occlusion. Conclusion: CTGF is expressed in cardiomyocytes in CAV. Increased expression of CTGF in cardiac allografts is associated with development of CAV and fibrosis formation.

Advances in the field of clinical lung transplantation must rely on observations made in animal models. In this study, we introduced a new procedure in the rat, orthotopic left lung transplantation without using the cuff technique, in which the donor pulmonary artery, pulmonary vein, and membranous parts of the bronchus were anastomosed continuously in the lumen using a mattress suture under a surgical microscope; meanwhile, a second, low-pressure perfusion through the pulmonary artery and turnover of the vascular stump were made, which also made the vessel anastomosis easy. Transplantations were completed in 68 rats (89.5%), the mean time used for suturing the left lung hilar structure was 23.5 ± 4.6 min. All lung grafts had good life-sustaining function because of there being no cuff-induced granulation tissue in bronchial anastomotic stoma, and three out of 12 allografts were observed with active bronchiolitis obliterans lesions at 8 weeks after transplantation. This model is a simple, valuable experimental model for studying lung transplantation and new therapies for preventing acute or chronic rejection. [ABSTRACT FROM AUTHOR]

The giant-colony-forming haptophyte Phaeocystis globosa has caused several large-scale blooms in the Beibu Gulf since 2011, but the distribution and dynamics of the blooms remained largely unknown. In this study, colonies of P. globosa, as well as membrane-concentrated phytoplankton samples, were collected during eight cruises in the Beibu Gulf from September 2016 to August 2017. Pigments were analyzed by high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). The pigment 199-hexanoyloxyfucoxanthin (hexfuco), generally considered a diagnostic pigment for Phaeocystis, was not detected in P. globosa colonies in the Beibu Gulf, whereas 199-butanoyloxyfucoxanthin (butfuco) was found in all colony samples. Moreover, but-fuco in membrane-concentrated phytoplankton samples exhibited a similar distribution pattern to that of P. globosa colonies, suggesting that but-fuco provided the diagnostic pigment for bloom-forming P. globosa in the Beibu Gulf. Based on the distribution of but-fuco in different water masses in the region prior to the formation of intensive blooms, it is suggested that P. globosa blooms in the Beibu Gulf could originate from two different sources. [ABSTRACT FROM AUTHOR]

The identification of core genes involved in the biosynthesis of saxitoxin (STX) offers a great opportunity to detect toxic algae associated with paralytic shellfish toxins (PST). In the Yellow Sea (YS) in China, both toxic and nontoxic Alexandrium species are present, which makes it a difficult issue to specifically monitor PST-producing toxic algae. In this study, a quantitative PCR (qPCR) assay targeting sxtA4, a domain in the sxt gene cluster that encodes a unique enzyme involved in STX biosynthesis, was applied to analyze samples collected from the YS in spring of 2012. The abundance of two toxic species within the Alexandrium tamarense species complex, i.e., A. fundyense and A. pacificum, was also determined with TaqMan-based qPCR assays, and PSTs in net-concentrated phytoplankton samples were analyzed with high-performance liquid chromatography coupled with a fluorescence detector. It was found that the distribution of the sxtA4 gene in the YS was consistent with the toxic algae and PSTs, and the quantitation results of sxtA4 correlated well with the abundance of the two toxic species (r = 0.857). These results suggested that the two toxic species were major PST producers during the sampling season and that sxtA-based qPCR is a promising method to detect toxic algae associated with PSTs in the YS. The correlation between PST levels and sxtA-based qPCR results, however, was less significant (r = 0.552), implying that sxtA-based qPCR is not accurate enough to reflect the toxicity of PST-producing toxic algae. The combination of an sxtA-based qPCR assay and chemical means might be a promising method for monitoring toxic algal blooms. [ABSTRACT FROM AUTHOR]