Adaptive layer-based computer-generated holograms.

We propose a novel, to the best of our knowledge, and fast adaptive layer-based (ALB) method for generating a computer-generated hologram (CGH) with accurate depth information. A complex three-dimensional (3D) object is adaptively divided into layers along the depth direction according to its own non-uniformly distributed depth coordinates, which reduces the depth error caused by the conventional layer-based method. Each adaptive layer generates a single-layer hologram using the angular spectrum method for diffraction, and the final hologram of a complex three-dimensional object is obtained by superimposing all the adaptive layer holograms. A hologram derived with the proposed method is referred to as an adaptive layer-based hologram (ALBH). Our demonstration shows that the desired reconstruction can be achieved with 52 adaptive layers in 8.7 s, whereas the conventional method requires 397 layers in 74.9 s.

Comparison of adaptive optical scanning holography based on new evaluation methods.

Adaptive Optical Scanning Holography (AOSH) represents a powerful technique that employs an adaptive approach to selectively omit certain lines within holograms, guided by the utilization of Normalized-Mean-Error (NME) as a predictive measure. This approach effectively diminishes scanning time and conserves the storage space required for data preservation. However, there exists alternative methods superior to NME in terms of evaluating the model's efficacy. This paper introduces two novel methods, namely Normalized-Root-Mean-Square-Error (NRMSE) and Normalized-Mean-Square-Error (NMSE), into the AOSH system, leading to the development of NRMSE-AOSH and NMSE-AOSH. These new systems aim to further minimize duration of holographic recording. Through a comparative analysis of hologram lines between the two newly proposed AOSH systems and the original AOSH, we demonstrate that both NRMSE-AOSH and NMSE-AOSH effectively reduce the number of hologram lines while maintaining the hologram's informational content. Among the three methods, our two new methods exhibit better performance compared with the original method.

Holographic Properties of Irgacure 784/PMMA Photopolymer Doped with SiO2 Nanoparticles.

To enhance the holographic properties, one of the main methods is increasing the solubility of the photosensitizer and modifying the components to improve the modulation of the refractive index in the photopolymer. This study provides evidence, through the introduction of a mutual diffusion model, that the incorporation of SiO2 nanoparticles in photopolymers can effectively enhance the degree of refractive index modulation, consequently achieving the objective of improving the holographic performance of the materials. Different concentrations of SiO2 nanoparticles have been introduced into highly soluble photosensitizer Irgacure 784 (solubility up to 10wt%)-doped poly-methyl methacrylate (Irgacure 784/PMMA) photopolymers. Holographic measurement experiments have been performed on the prepared samples, and the experiments have demonstrated that the Irgacure 784/PMMA photopolymer doped with 1.0 × 10-3wt% SiO2 nanoparticles exhibits the highest diffraction efficiency (74.5%), representing an approximate 30% increase in diffraction efficiency as compared to an undoped photopolymer. Finally, we have successfully achieved the recording of real objects on SiO2/Irgacure 784/PMMA photopolymers, demonstrated by the SiO2/Irgacure 784/PMMA photopolymer material prepared in this study, which exhibits promising characteristics for holographic storage applications. The strategy of doping nanoparticles (Nps) in Irgacure 784/PMMA photopolymers has also provided a new approach for achieving high-capacity holographic storage in the future.

Efficient rendering by parallelogram-approximation for full analytical polygon-based computer-generated holography using planar texture mapping.

We have developed a full analytical method with texture mapping for polygon-based computer-generated holography. A parallel planar projection mapping for holographic rendering along with affine transformation and self-similar segmentation is derived. Based on this method, we further propose a parallelogram-approximation to reduce the number of polygons used in the polygon-based technique. We demonstrate that the overall method can reduce the computational effort by 50% as compared to an existing method without sacrificing the reconstruction quality based on high precision rendering of complex textures. Numerical and optical reconstructions have shown the effectiveness of the overall scheme.

LaTaON2 Mesoporous Single Crystals for Efficient Photocatalytic Water Oxidation and Z-Scheme Overall Water Splitting.

LaTaON2 porous single crystals (PSCs), integrating structural coherence and porous microstructures, will warrant promising photocatalytic performance. The absence of grain boundaries in PSCs ensures rapid photocarrier transportation from bulk to the surface, thereby mitigating photocarriers' recombination. Porous microstructures not only provide ample reachable surface to host photochemical reactions but also reinforce photon-matter interactions by additional photon reflection/scattering. Here, we have synthesized LaTaON2 PSCs via a topotactic route and show significantly improved photocatalytic performance. Efficient water oxidation into O2 has been realized by LaTaON2 PSCs with an apparent quantum efficiency as high as 5.7% at 420 ± 20 nm. Stable overall water splitting into stoichiometric H2 and O2 has also been achieved in a Z-scheme setup using LaTaON2 PSCs as the O2 evolution photocatalyst. These results not only prove that PSCs facilitate photocarrier migrations, which in turn deliver exceptional photocatalytic performance, but also imply that PSCs are useful to reinvigorate conventional semiconductor photocatalysts toward efficient solar energy conversions.

The relationship between serum fibrinogen-like protein 2 concentrations and 30-day mortality of patients with traumatic brain injury.

BACKGROUND: Fibrinogen-like protein 2 (FGL2) is an inflammatory procoagulant protein. We discerned the impact of serum FGL2 on trauma severity and 30-day mortality in patients with traumatic brain injury (TBI). METHODS: A total of 114 severe TBI patients were subjected to assessment of trauma severity using the Glasgow coma scale (GCS). Measurement of the serum concentrations of FGL2 was done. 114 matched control subjects for their age and sex were included for comparison of serum concentration of FGL2. RESULTS: The concentration of FGL2 was dramatically increased in the patients as compared with the control subjects. FGL2 concentration was inversely correlated with GCS score among the patients. The non-survivors within 30 days exhibited substantially higher FGL2 concentrations than the alive. FGL2 concentrations discriminated the patients at risk of 30-day death with significantly high area under receiver operating characteristic curve. Serum FGL2 emerged as an independent predictor for mortality and overall survival at 30 days after head trauma. CONCLUSIONS: Serum FGL2 is a promising biomarker for assessing the severity and prognosis in severe TBI.

Serum CXCL12 concentration in patients with severe traumatic brain injury are associated with mortality.

BACKGROUND: CXC chemokine ligand-12 (CXCL12) is released during brain injury. The objective of this study was to investigate relationship between serum CXCL12 concentration, mortality and trauma severity in patients with traumatic brain injury (TBI). METHODS: We determined serum CXCL12 concentration of 132 controls and 132 patients with severe TBI. Trauma severity was assessed using Glasgow Coma Scale (GCS) score. The end-point of the study was 30-day mortality. RESULTS: Serum CXCL12 concentration were significantly higher in the patients than in the controls (13.3±6.8 vs. 1.5±0.5 ng/ml, P<0.001). There was a negative correlation between CXCL12 concentration and GCS scores (r=-0.588, P<0.001). The optimal cutoff value of CXCL12 as a mortality indicator was estimated to be 15.4 ng/ml, which yielded a sensitivity of 71.0% and a specificity of 72.2%, with the area under curve at 0.808 [95% confidence (CI), 0.730-0.871]. Serum CXCL12 concentration>19.5 ng/ml were associated independently with 30-day mortality (odds ratio, 6.951; 95% CI, 2.027-18.477; P<0.001) and 30-day overall survival (hazard ratio, 4.398; 95% CI, 2.088-15.286; P<0.001). CONCLUSIONS: Increased serum CXCL12 concentration is associated highly with trauma severity and mortality following TBI.

Plasma levels of adrenomedullin in patients with traumatic brain injury: potential contribution to prognosis.

High plasma levels of adrenomedullin have been associated with stroke severity and clinical outcomes. This study aimed to analyze plasma levels of adrenomedullin in traumatic brain injury and their association with prognosis. One hundred and forty-eight acute severe traumatic brain injury and 148 sex- and age-matched healthy controls were recruited in this study. Plasma adrenomedullin concentration was measured by enzyme-linked immunosorbent assay. Unfavorable outcome was defined as Glasgow Outcome Scale score of 1-3. Compared to controls, the patients had significantly higher plasma concentrations of adrenomedullin, which were also highly associated negatively with Glasgow Coma Scale score. Plasma adrenomedullin level was proved to be an independent predictor for 6-month mortality and unfavorable outcome of patients in a multivariate analysis. A receiver operating characteristic curve was configured to show that a baseline plasma adrenomedullin level predicted 6-month mortality and unfavorable outcome of patients with high area under curve. The predictive performance of the plasma adrenomedullin concentration was also similar to that of Glasgow Coma Scale score for the prediction of 6-month mortality and unfavorable outcome of patients. In a combined logistic-regression model, adrenomedullin improved the area under curve of Glasgow Coma Scale score for the prediction of 6-month mortality and unfavorable outcome of patients, but the differences did not appear to be statistically significant. Thus, high plasma levels of adrenomedullin are associated with head trauma severity, and may independently predict long-term clinical outcomes of traumatic brain injury.