To assess whether the 3-dimensional (3D) structural configuration of the central retinal vessel trunk and its branches (CRVT&B) could be used as a diagnostic marker for glaucoma.
Retrospective, ...deep-learning approach diagnosis study.
We trained a deep learning network to automatically segment the CRVT&B from the B-scans of the optical coherence tomography (OCT) volume of the optic nerve head. Subsequently, 2 different approaches were used for glaucoma diagnosis using the structural configuration of the CRVT&B as extracted from the OCT volumes. In the first approach, we aimed to provide a diagnosis using only 3D convolutional neural networks and the 3D structure of the CRVT&B. For the second approach, we projected the 3D structure of the CRVT&B orthographically onto sagittal, frontal, and transverse planes to obtain 3 two-dimensional (2D) images, and then a 2D convolutional neural network was used for diagnosis. The segmentation accuracy was evaluated using the Dice coefficient, whereas the diagnostic accuracy was assessed using the area under the receiver operating characteristic curves (AUCs). The diagnostic performance of the CRVT&B was also compared with that of retinal nerve fiber layer (RNFL) thickness (calculated in the same cohorts).
Our segmentation network was able to efficiently segment retinal blood vessels from OCT scans. On a test set, we achieved a Dice coefficient of 0.81 ± 0.07. The 3D and 2D diagnostic networks were able to differentiate glaucoma from nonglaucoma subjects with accuracies of 82.7% and 83.3%, respectively. The corresponding AUCs for the CRVT&B were 0.89 and 0.90, higher than those obtained with RNFL thickness alone (AUCs ranging from 0.74 to 0.80).
Our work demonstrated that the diagnostic power of the CRVT&B is superior to that of a gold-standard glaucoma parameter, that is, RNFL thickness. Our work also suggested that the major retinal blood vessels form a “skeleton”—the configuration of which may be representative of major optic nerve head structural changes as typically observed with the development and progression of glaucoma.
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•Au–silica nanorods were blended into the active layers of PSCs.•The PCE of the devices was significantly increased relative to control devices.•IPCE, absorption and PL spectra ...confirm that incorporation of Au nanorods increased light absorption.•Light scattering effects was demonstrated by diffuse transmission and reflection spectra.
We report the use of chemically synthesized gold (Au)–silica core–shell nanorods with the length of 92.5±8.0nm and diameter of 34.3±4.0nm for the efficiency enhancement of bulk heterojunction (BHJ) polymer solar cells. Silica coated Au nanorods were randomly blended into the BHJ layers of these solar cells. This architecture inhibits the carrier recombination at the metal/polymer interface and effectively exploits light absorption at the surface plasmon resonance wavelengths of the Au–silica nanorods. To match the two plasmon resonant peaks of the Au–silica nanorods, we employed a low bandgap polymer, poly2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta2,1-b;3,4-b′ dithiophene)-alt-4,7-(2,1,3-benzothiadiazole) (PCPDTBT) to construct a solar cell. The absorption spectrum of PCPDTBT:6,6-phenyl-C71-butyric acid methyl ester (PC70BM) is relatively wide and matches the two plasmon resonance peaks of Au–silica nanorods, which leads to greater plasmonic effects. We also constructed the poly(3-hexylthiophene):6,6-phenyl-C61-butyric acid methyl ester (P3HT:PC60BM) cells for comparison. The absorption spectrum of P3HT:PC60BM only overlaps one of the plasmon resonance peak of Au–silica nanorods. The efficiency of the P3HT:PC60BM device incorporating optimized Au–silica nanorods is enhanced by 12.9% from 3.17% to 3.58%, which is due to the enhanced light absorption. Compared with the P3HT:PC60BM device with Au–silica nanorods, the PCPDTBT:PC70BM device with 1wt% Au–silica nanorods concentration has a higher efficiency of 4.4% with an increase of 26%.
Abstract Genetic characteristics were analysed for recent clinical isolates of methicillin-resistant and -susceptible Staphylococcus aureus (MRSA and MSSA respectively) in Kathmandu, Nepal. MRSA ...isolates harbouring Panton-Valentine leukocidin (PVL) genes were classified into ST1, ST22 and ST88 with SCC mec -IV and ST772 with SCC mec -V (Bengal Bay clone), while PVL-positive MSSA into ST22, ST30 and ST772. ST22 isolates (PVL-positive MRSA and MSSA, PVL-negative MRSA) possessed a variant of elastin binding protein gene ( ebpS ) with an internal deletion of 180 bp, which was similar to that reported for ST121 S. aureus previously outside Nepal. Phylogenetic analysis indicated that the ebpS variant in ST22 might have occurred independently of ST121 strains. This is the first report of ST772 PVL-positive MRSA in Nepal and detection of the deletion variant of ebpS in ST22 S. aureus.
Abstract Chikungunya viruses from the 2017 outbreak in Dhaka, Bangladesh, were analysed phylogenetically. E1 sequences from 21 strains belonged to the Indian Ocean clade of the East/Central/South ...African (ECSA) genotype, forming a novel cluster with latest South Asian strains. They lacked the A226V substitution.
In Bangladesh, coronavirus disease 2019 (COVID-19) has been highly prevalent during late 2020, with nearly 500 000 confirmed cases. In the present study, the spike (S) protein of severe acute ...respiratory coronavirus 2 (SARS-CoV-2) circulating in Bangladesh was genetically investigated to elucidate the diversity of mutations and their prevalence. The nucleotide sequence of the S protein gene was determined for 15 SARS-CoV-2 samples collected from eight divisions in Bangladesh, and analysed for mutations compared with the reference strain (hCoV-19/Wuhan/WIV04/2019). All the SARS-CoV-2 S genes were assigned to B.1 lineage in G clade, and individual S proteins had 1–25 mutations causing amino acid substitution/deletion. A total of 133 mutations were detected in 15 samples, with D614G being present in all the samples; 53 were novel mutations as of January 2021. On the receptor-binding domain, 21 substitutions including ten novel mutations were identified. Other novel mutations were located on the N-terminal domain (S1 subunit) and dispersed sites in the S2 subunit, including two substitutions that remove potential N-glycosylation sites. A P681R substitution adjacent to the furin cleavage site was detected in one sample. All the mutations detected were located on positions that are functionally linked to host transition, antigenic drift, host surface receptor binding or antibody recognition sites, and viral oligomerization interfaces, which presumably related to viral transmission and pathogenic capacity.
The dependences of the defining coefficients of the blade operation on various environmental conditions are considered. The best airfoil of the blade with high efficiency in a wide range of operating ...conditions is determined.
Dengue virus (DENV) that caused an outbreak in Dhaka, Bangladesh during 2018 was analysed phylogenetically. DENV samples were classified into type 2-Cosmopolitan genotype (54%) and type 3-genotype I ...(46%), indicating co-circulation of two DENV types and resurgence of type 3 associated with genotype replacement.
Mathematical models and numerical methods for solving optimal control problems in the shaping of monolithic panels by stretching on the punch have been developed. As criteria, residual displacements ...and damage in plasticity are considered. The algorithms implemented in MSC.Marc allow us to calculate the optimal parameters of the stretch forming press work.
Summary
Potential FRAX®-based major osteoporotic fracture (MOF) and hip fracture (HF) intervention thresholds (ITs) for postmenopausal Singaporean women were explored. Age-dependent ethnic-specific ...and weighted mean ITs progressively increased with increasing age. Fixed ITs were derived via discriminatory value analysis. MOF and HF ITs with highest the Youden index were chosen as optimal.
Introduction
We aimed to explore FRAX®-based intervention thresholds (ITs) to potentially guide osteoporosis treatment in Singapore, a multi-ethnic nation.
Method
One thousand and one Singaporean postmenopausal community-dwelling women belonging to Chinese, Malay and Indian ethnicities underwent clinical risk factor (CRF) and BMD assessment. FRAX® major osteoporotic fracture (MOF) and hip fracture (HF) probabilities were calculated using ethnic-specific models. We employed the translational logic adopted by NOGG (UK), whereby osteoporosis treatment is recommended to any postmenopausal woman whose fracture probability based on other CRFs is similar to or exceeds that of an age-matched woman with a fracture. Using the same logic, ethnic-specific and mean weighted age-dependent ITs were computed. Employing these age-dependent ITs as a reference, the performance of fixed (age-independent) ITs were examined using ROC curves and discriminatory analysis, with the highest Youden index (YI) (sensitivity + specificity − 1) used to identify the optimal MOF and HF ITs.
Results
The mean age was 58.9 (6.9) years. Seven hundred and eighty-nine (79%) women were Chinese, 136 (13.5%) Indian and 76 (7.5%) Malay. Age-dependent MOF ITs ranged from 3.1 to 33%, 2.5 to 17% and 2.5 to 16% whilst HF ITs ranged from 0.7 to 17%, 0.4 to 6% and 0.4 to 6.3% in Chinese, Malay and Indian women, respectively, between the ages of 50 and 90 years. The weighted age-dependent MOF and HF ITs ranged from 2.9% and 0.6%, respectively, at the age of 50, to 28% and 14% at 90 years of age. Fixed MOF/HF ITs of 5.5%/1%, 2.5%/1% and 2.5%/0.25% were identified as the most optimal by the highest YI in Chinese, Malay and Indian women, respectively. Fixed MOFP and HF ITs of 4% and 1%, respectively, were found to be most optimal on the weighted means analysis.
Conclusion
The ITs for osteoporosis treatment in Singapore show marked variations across ethnicities. Weighted mean thresholds may overcome the dilemma of intervening at different thresholds for different ethnicities. Choosing fixed ITs may have to involve trade-offs between sensitivity and specificity. FRAX®-based age-dependent or the fixed intervention thresholds suggested as an alternative to be considered for use in Singapore though further studies on the societal and health economic impacts of choosing these thresholds in Singapore are needed.
The significantly enhanced performance upon incorporation of Au nanoparticles in solution-processed small-molecule solar cells is demonstrated. Simultaneously incorporating Au nanospheres into the ...hole transport layer and Au-silica nanorods into the active layer results in superior broadband absorption improvement in the device with a power conversion efficiency of 8.72% with 31% enhancement.
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