A Deep Learning Approach to Denoise Optical Coherence Tomography Images of the Optic Nerve Head

Purpose: To develop a deep learning approach to de-noise optical coherence tomography (OCT) B-scans of the optic nerve head (ONH). Methods: Volume scans consisting of 97 horizontal B-scans were acquired through the center of the ONH using a commercial OCT device (Spectralis) for both eyes of 20 subjects. For each eye, single-frame (without signal averaging), and multi-frame (75x signal averaging) volume scans were obtained. A custom deep learning network was then designed and trained with 2,328 "clean B-scans" (multi-frame B-scans), and their corresponding "noisy B-scans" (clean B-scans + gaussian noise) to de-noise the single-frame B-scans. The performance of the de-noising algorithm was assessed qualitatively, and quantitatively on 1,552 B-scans using the signal to noise ratio (SNR), contrast to noise ratio (CNR), and mean structural similarity index metrics (MSSIM). Results: The proposed algorithm successfully denoised unseen single-frame OCT B-scans. The denoised B-scans were qualitatively similar to their corresponding multi-frame B-scans, with enhanced visibility of the ONH tissues. The mean SNR increased from $4.02 \pm 0.68$ dB (single-frame) to $8.14 \pm 1.03$ dB (denoised). For all the ONH tissues, the mean CNR increased from $3.50 \pm 0.56$ (single-frame) to $7.63 \pm 1.81$ (denoised). The MSSIM increased from $0.13 \pm 0.02$ (single frame) to $0.65 \pm 0.03$ (denoised) when compared with the corresponding multi-frame B-scans. Conclusions: Our deep learning algorithm can denoise a single-frame OCT B-scan of the ONH in under 20 ms, thus offering a framework to obtain superior quality OCT B-scans with reduced scanning times and minimal patient discomfort

Computerized FDTD Method for Longitudinal Optical Phonon Energy on Semiconductor Hybrid Structure for High Power Devices Fabrication

The research problem in this study is the longitudinal optical phonon energy on metal/semiconductor interface for high performance semiconductor device. The research solution is to make the software model with finite difference time domain (FDTD) solution for transmission and reflection pulse between metal and semiconductor interface for carrier dynamics effects. The objective of this study is to find the quantum mechanics understanding on interface engineering for fabricating the high performance device for future semiconductor technology development. The analysis was carried out with the help of MATLAB. The quantum mechanical spatial field on metal-semiconductor stripe structure has been analyzed by FDTD techniques. This emission reveals a characteristic polar radiation distribution of electric dipoles and a wavelength independent of the structure size or the direction of emission; consequently, it is attributed to thermally generate electric dipoles resonating with the longitudinal optical phonon energy. Phonon energy occurs lattice vibration of material by the polarization of light, if the material has rigid structure reflect back the incident light. So, high reflective metal-semiconductor structure always use as photodectors devices in optical fiber communication. No lattice vibration material structure has no phonon effect, so this structure based devices can get high performance any other structure based devices. The transmission and reflection coefficient of metal-semiconductor GaN/Au layer structure compare with GaN/Ti and GaN/Pt structure. Parallel (P) and transverse (S) polarization of light incident on a metal-semiconductor nanolayer structure with IR wavelength. Efficient use of the layer by layer (LbL) method to fabricate nanofilms requires meeting certain conditions and limitations that were revealed in the course of research on model systems

XRD and SEM Analysis, and Semiconductor Type Determination of TiO2 for Dye-sensitized Solar Cell

Titanium dioxide (TiO2) is a wide band-gap n-type semiconductor. Anatase TiO2 is the most common structure used in high performance dye-sensitized solar cell (DSSC). Nanoporous TiO2 serves double-duty as an electron acceptor and a scaffold to hold large numbers of dye molecules in DSSC. The porosity of TiO2 is a key feature as it has roughly a thousand times greater a surface area than the equivalent flat area. In this work, TiO2 crystallite size (43.55 nm) has been calculated by using XRD data, and the morphology and the grain-size of TiO2 (average grain size of 0.2 mm ~ 0.3 mm) with different solvents have been also studied by SEM

ミャンマーイネ チホウ ヒンシュ ニオケル エステラーゼアイソザイム ノ タガタ

ミャンマーのイネ地方品種491点を用いて3つのエステラーゼアイソザイム(Est1,Est2,Est3)のザイモグラムを調査し,地域間における遺伝子型頻度,遺伝子座の平均遺伝子多様度および多様性指数を解析した。ミャンマーの地方品種には,Est1,Est2,Est3座の対立遺伝子で決定される 12種類の遺伝子型のうち,10型を除くすべての遺伝子型が存在した。とくに 1型,3型および 5型の3種類の遺伝子型の頻度が高かった。地域別でみると,どの地域でも多様な変異がみられたが,とくに北部のSagaing管区と西部丘陵地域のChin州と東部丘陵地域の Shan 州の品種には,ほとんどの遺伝子型が存在した。インドのアッサム州と隣接する 西部丘陵地域の Chin 州では,1型の頻度が最も高く,3型および 5型の遺伝子型も多い傾向が認められた。一方,イネの地方品種のエステラーゼアイソザイムの多様性に地域間差異があまり見られなかった。このことは,アイソザイムの酵素機能に差異がなく,環境適応に伴う自然選択や栽培者による人為選抜の影響を受けにくいことによると考えられる。さらに,エステラーゼアイソザイムに限れば,ミャンマー全土が多様性地域に包括され,目立った地域的分化が生じていない為と考えられた。Esterase isozymes have often used for investigating phylogenetic differentiation of rice landraces. Three loci of Est1, Est2 and Est3 have been identified where 2, 3, and 2 alleles are respectively included. The combinations of those alleles in the three loci produce 12 genotypes. Myanmar landraces are found to have eleven genotypes among them. Such genotypes as 1, 3 and 5 are more frequent than any others and most genotypes of esterase isozyme showed similarly frequencies in every region. The result indicated that Myanmar landraces have a wide range of genetic variation. The variation of esterase isozyme was considered to be neutral to natural and artificial selection as well.Genotypes of esterase isozyme were greatly diverse but no significant difference of genotypic frequency was observed among regions. The genotypes of esterase isozyme in Myanmar are as diverse as neighboring areas, as being reported earlier

In vivo measurements of prelamina and lamina cribrosa biomechanical properties in humans

Purpose: To develop and use a custom virtual fields method (VFM) to assess the biomechanical properties of human prelamina and lamina cribrosa (LC) in vivo. Methods: Clinical data of 20 healthy, 20 ocular hypertensive (OHT), 20 primary open-angle glaucoma, and 16 primary angle-closure glaucoma eyes were analyzed. For each eye, the intraocular pressure (IOP) and optical coherence tomography (OCT) images of the optic nerve head (ONH) were acquired at the normal state and after acute IOP elevation. The IOP-induced deformation of the ONH was obtained from the OCT volumes using a three-dimensional tracking algorithm and fed into the VFM to extract the biomechanical properties of the prelamina and the LC in vivo. Statistical measurements and P values from the Mann-Whitney-Wilcoxon tests were reported. Results: The average shear moduli of the prelamina and the LC were 64.2 ± 36.1 kPa and 73.1 ± 46.9 kPa, respectively. The shear moduli of the prelamina of healthy subjects were significantly lower than those of the OHT subjects. Comparisons between healthy and glaucoma subjects could not be made robustly due to a small sample size. Conclusions: We have developed a methodology to assess the biomechanical properties of human ONH tissues in vivo and provide preliminary comparisons in healthy and OHT subjects. Our proposed methodology may be of interest for glaucoma management

Project-based learning module on creativity and entrepreneurship products subject: Validity and empirical effect

The learning process for Creativity and Entrepreneurship Products subjects in Vocational High Schools still uses printed books which are verbal in nature so this will make it difficult for students to learn the learning material. Apart from that, the learning method used the lecture method which is certainly less effective in supporting students' understanding of the material so that learning is more teacher-centred. Meanwhile, the demand for the current ‘Merdeka’ curriculum is that learning must be student-centered. This research aimed at developing learning tools of PjBL (Project Based Learning) based teaching modules on the Product Creativity and Entrepreneurship subjects. This research was a type of research and development using the ADDIE development model. There were 12 experts who validate this module from 3 aspects, namely material, media and model, and language aspects and there were 30 students for limited trials. The results of this research showed that this module was valid and has a positive effect in supporting the learning process for the Product Creativity and Entrepreneurship subjects. This research had implications for the effectiveness of Creativity and Entrepreneurship Products learning and being one method that can be used by teachers in this learning

Spatial distribution, work patterns, and perception towards malaria interventions among temporary mobile/migrant workers in artemisinin resistance containment zone

BACKGROUND: Mobile populations are at a high risk of malaria infection and suspected to carry and spread resistant parasites. The Myanmar National Malaria Control Programme focuses on preventive interventions and vector control measures for the temporary mobile/migrant workers in Myanmar Artemisinin Resistance Containment Zones. METHODS: A prospective cross-sectional study was conducted in 2012 in Kawthaung and Bokepyin townships of Tanintharyi Region, Myanmar, covering 192 mobile/migrant aggregates. The objectives were to identify the spatial distribution of the mobile/migrant populations, and to assess knowledge, attitudes, perceptions, and practices concerning malaria prevention and control, and their preferred methods of interventions. The structure of the192 migrant aggregates was investigated using a migrant mapping tool. Individual and household information was collected by structured interviews of 408 respondents from 39 aggregates, supplemented by 12 in-depth interviews of health care providers, authorities, volunteers, and employers. Data were analyzed by triangulating quantitative and qualitative data. RESULTS: The primary reasons for the limitation in access to formal health services for suspected malaria within 24 hours were identified to be scattered distribution of migrant aggregates, variable working hours and the lack of transportation. Only 19.6% of respondents reported working at night from dusk to dawn. Among study populations, 73% reported a perceived risk of contracting malaria and 60% reported to know how to confirm a suspected case of malaria. Moreover, only 15% was able to cite correct antimalarial drugs, and less than 10% believed that non-compliance with antimalarial treatment may be related to the risk of drug resistance. About 50% of study population reported to seeking health care from the public sector, and to sleep under ITNs/LLINs the night before the survey. There was a gap in willingness to buy ITNs/LLINs and affordability (88.5% vs. 60.2%) which may affect their sustained and consistent use. Only 32.4% across all aggregates realized the importance of community participation in effective malaria prevention and control. CONCLUSIONS: Community-based innovative approaches through strong collaboration and coordination of multi-stakeholders are desirable for relaying information on ITNs/LLINs, rapid diagnostic test, and artemisinin combination therapy and drug resistance successfully across the social and economic diversity of mobile/migrant aggregates in Myanmar