We report a novel and fast method for converting a digital, complex Fresnel hologram into a phase-only hologram. Briefly, the pixels in the complex hologram are scanned sequentially in a row by row ...manner. The odd and even rows are scanned from opposite directions, constituting to a bidirectional error diffusion process. The magnitude of each visited pixel is forced to be a constant value, while preserving the exact phase value. The resulting error is diffused to the neighboring pixels that have not been visited before. The resulting novel phase-only hologram is called the bidirectional error diffusion (BERD) hologram. The reconstructed image from the BERD hologram exhibits high fidelity as compared with those obtained with the original complex hologram.
Abstract
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.
Abstract
Treat-to-target strategies have changed the approach to management of many chronic conditions, with improvements in patient outcomes. The key to success of treat to target is the ...availability of validated treatment endpoints, which have been difficult to derive for SLE, a condition notorious for its heterogeneity. This review will focus on the development and validation of the definitions of remission in SLE framework and the lupus low disease activity state. Lupus low disease activity state is more attainable than remission, with a stepwise concentric relationship between the target states indicating increasing stringency. Both lupus low disease activity state and definitions of remission in SLE remission have been proven to be associated with reduction in disease flares, reduced risk of accrual of irreversible end organ damage, and improvement in patient reported outcomes. These endpoints have therefore provided the key for the development of a treat-to-target approach in clinical practice in SLE and for the design of future clinical trials.
A fast and non-iterative method for generating a phase-only hologram, hereafter referred to as the patterned-phase-only hologram (PPOH), is reported in this paper. Briefly, a phase mask with a ...periodic phase pattern is added to the source image, and converted into a hologram. Subsequently, only the phase component is retained as a phase-only hologram. Experimental evaluation reveals that the visual quality of the reconstructed images of the PPOH generated with our proposed method is favorable, and superior to that obtained with existing methods.
Acquisition of drug resistance is one of the main obstacles encountered in cancer chemotherapy. Overexpression of multi-drug resistance 1 (MDR1) gene and its protein product P-glycoprotein, ...accompanied with a decrease in doxorubicin accumulation level, was observed in doxorubicin-resistant R-HepG2 cells, a subline derived by selection of human hepatocellular carcinoma HepG2 cells with doxorubicin. In addition, Northern-blot analysis revealed an eight fold upregulation of the imprinted H19 mRNA in R-HepG2 cells. H19 knockdown by transfection with antisense H19 oligonucleotides suppressed the MDR1/P-glycoprotein expression, increased the cellular doxorubicin accumulation level and sensitized doxorubicin toxicity in both HepG2 parent cells and R-HepG2 cells. Results from methylation-specific polymerase chain reaction analysis indicated that the MDR1 gene promoter was hypomethylated in R-HepG2 cells. Antisense H19 oligonucleotides transfection induced a marked increase in the percentage of MDR1 promoter methylation and decrease in MDR1 expression in R-HepG2 cells. Thus, the H19 gene is believed to induce P-glycoprotein expression and MDR1-associated drug resistance at least in liver cancer cells through regulation of MDR1 promoter methylation.
To identify predictors of organ damage and specifically the relationship between prolonged disease remission or low disease activity and damage accrual in a longitudinal cohort of SLE patients.
Data ...were prospectively assessed including the occurrence of minor/major flares. Once a year remission and Lupus Low Disease Activity State (LLDAS) were determined retrospectively. A prediction model for damage accrual during follow-up was constructed with backward logistic regression analyses. Secondly, odds ratios (ORs) for damage accrual (SLICC damage index increase of ⩾ 1 during follow-up) were calculated for patients with or without prolonged remission during 5 years, and with or without LLDAS in ⩾ 50% of observations.
Data from 183 patients with a median follow-up duration of 5.0 years were analysed. The most significant predictors for damage accrual were: occurrence of ⩾ 1 major flare, mean daily prednisone dose during follow-up and nephrological manifestations at baseline. Prolonged remission was present in 32.5% (38/117) and LLDAS in ⩾ 50% of observations in 64.5% (118/183) of patients. Both the presence of prolonged remission during 5 years and LLDAS in ⩾ 50% of observations were associated with a reduced risk of damage accrual (OR = 0.20, 95% CI: 0.07, 0.53, P = 0.001 and OR = 0.52, 95% CI: 0.28, 0.99, P = 0.046, respectively).
This cohort study shows that prolonged remission and LLDAS were associated with an improved outcome, as determined by yearly assessments. In order to improve the outcome in SLE patients, future studies should investigate whether these targets can be reached actively with therapeutic strategies.
Background
Vascularity of hypertrophic scar is a key indicator of scar maturation and a vital parameter of evaluating effects of scar management interventions. This study aims to explore the ...construct validity of dermoscopy for measuring vascularity of hypertrophic scar and its predictive ability of scar thickness change.
Methods
Patients with hypertrophic scars were recruited for scar assessments at baseline and at one‐month follow‐up, which consisted of the Patient and Observer Scar Assessment Scale, DermaLab Combo, ultrasound and dermoscopy.
Results
Forty hypertrophic scars in the active proliferation stage were included in this study. The dermoscopic measurements based on color significantly discriminated the hypertrophic scars from the healthy skin (P < .001). In addition, they showed moderate to strong correlations with the vascularity component of the Patient and Observer Scar Assessment Scale (r = −.438, P < .01; r = −.461, P < .01; and r = −.437, P < .01) and the erythema value as measured by DermaLab Combo (r = −.474, P < .01; r = −.603, P < .01; and r = −.498, P < .01). Weak to moderate correlations of the micro‐vessel percentage were observed with the vascularity of Patient and Observer Scar Assessment Scale (r = .385, P < .01) and the erythema of DermaLab Combo (r = .444, P < .01). For prediction of the scars with high risk of thickness change, the green value by dermoscopy was the strongest predictor (AUC = 0.738, P = .034, 95%CI = 0.570‐0.906).
Conclusion
Dermoscopy, which evaluates scar vascularity by measuring scar color and micro‐vessel percentage, could be used as an objective assessment tool to indicate scar maturation and identify scars with active proliferation.
A sampled phase-only hologram (SPOH) is the phase component of the hologram of an object image with pixels being sampled with a periodic grid-cross pattern. The reconstructed image of a SPOH is a ...sparse image with abundant empty voids and degradation in sharpness and contrast. In this paper we proposed a method based on a new sampling scheme, together with stochastic binary search (SBS), to obtain an optimal sampling lattice that can be applied to generate phase-only holograms with enhanced reconstructed image. Experimental results show that with our proposed method, the fidelity and quality of the reconstructed image are increased.
"Horizontal strokes should be level and vertical strokes should be straight" is a common guideline in the teaching of Chinese handwriting. Measuring deviations in level horizontal and straight ...vertical strokes in students' Chinese handwriting is usually assessed manually. However, this task is time-consuming and may have inconsistent outcomes when judged by different people. In this paper, we aim to formulate a method to automatically evaluate the tilt and slant degrees of students' Chinese handwriting using digital handwriting tablets. Furthermore, we analyze the relationship between the tilt and slant features of students' Chinese handwriting and other demographic and handwriting features.
Five hundred and ninety-one primary school students from grades 1 to 6 were recruited in Hong Kong. Before the assessment, a grid paper was attached to a digital handwriting tablet. The participants were then asked to copy 90 Chinese characters from a template to the grid paper. Their handwriting processes were recorded as two-dimensional points and then analyzed. The tilt and slant of the students' handwriting were calculated based on the inclination level of their horizontal and vertical strokes. Linear regressions between slant/tilt degree of the manuscripts and other handwriting features were performed. The students' demographic information was also explored.
Slant was found to be significantly correlated to Gender (p < 0.001) and tilt×standard deviation of pen pressure (p < 0.001). Tilt was found to be significantly correlated to ground time (p < 0.001), slant (p < 0.001) and slant×special education need (p = 0.021).
Our results demonstrate the relationship between slant, tilt and Chinese handwriting performance in primary school children. Slant and tilt can be adopted as an indicator in students' special education need diagnosis, as tilt level in the students' Chinese handwriting was related to ground time and slant× special education need, while slant is related to tilt×standard deviation of pen pressure and female students. These findings may also inspire ways to increase special education need students' writing speed.
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