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In this paper, an improved coupled-mode method is used to design a launcher for a gyrotron quasi-optical mode converter at 170 Ghz with an operating mode of TE32,9. The new method calculates 25 coupled modes, which more accurately simulates the field distribution in the launcher. The diffraction field of the launcher with a spiral cut is calculated by using the scalar diffraction integral method with fast Fourier transform. The radiation power of the launcher is 99.94%, the Gaussian mode content of the radiation beam is 98.40%, the diffraction loss of the launcher is 0.0580%, and the radiation efficiency is 98.34%. The method proposed in this paper is fast in calculation and can be applied to the large-scale high-frequency gyrotron launcher.

The parent and radical-modified chitin units are computationally studied and the parent chitin unit possesses closed-shell singlet (CS) state as its ground state. Two radicals (CH3. and CH3CH2.) are chosen to modify the parent chitin unit. Calculations predict that CH3CH2·-modified chitin unit possesses the open-shell brokensymmetry (BS) singlet diradical ground state, different from that CH3·-modified chitin unit is a triplet diradical. That is to say, the magnetic conversion can occur from nonmagnetic exchange coupling to antiferromagnetic(AFM) or ferromagnetic(FM) exchange coupling by means of the radical modification method. The present work helps to get a basic understanding of structures and electronic properties of chitin and its radical-modified derivatives at the atomistic level. Moreover, it also provides a feasible way to design new chitin-based magnetic materials and organic magnetic switches. [ABSTRACT FROM AUTHOR]

Neovascular glaucoma (NVG), which is refractory to both medical management and surgical intervention, is a disastrous ocular disease for it always ends up with intolerable pain and extinguishing patients' residual visual function. Since insufficient acknowledge of the pathophysiological and molecular mechanisms of NVG, it has been laying a challenging dilemma of managing NVG in clinical practice for a long time. Along with the progression on some new agents and surgical options targeting certain possible roles in the NVG process, there seems having been some new sights but still much unknown and to be revealed. This review discusses the underlying etiologic diseases of NVG, molecular findings and characteristics of its pathogenic process, as well as the management of NVG in detail. In addition, here represents some of our hypothesis regarding the interesting findings about NVG in clinical practice, aiming to provide some new enlightenment for future research. [ABSTRACT FROM AUTHOR]

Ketones 6a–i were converted into their benzotriazolylamine adducts 8a–i either directly from the corresponding ketone 6a or via enamines 7b–i. Adducts 8a–i on treatment with Grignard reagents, lithium phenylacetylide, or heteroaryllithiums gave tertiary alkyl carbinamines 9a–h (47–61%), propargylamines 10a–i (30–98%), and α-heteroarylamines 11a–k (44–85%), respectively. [ABSTRACT FROM AUTHOR]

This paper proposes a method that combines the effective area method and the oblique factors to analyze and design dual-layer diffractive optical elements at large incident angles. The method considers the effects of shadow and shield on the diffraction efficiency, as well as the correction of phase delay due to oblique incidence. The relationships among the diffraction efficiency, incident wavelengths, incident angles and period widths were analyzed with our method. A detailed comparison of the proposed method with the scalar diffraction theory is presented. The method was validated by numerical simulations of vector diffraction theory and showed similar diffraction efficiency distributions at different wavelengths and incident angles. The method provides a simple and efficient way to design and apply DLDOEs.

Primary congenital glaucoma (PCG), a developmental glaucoma occurring due to angle anomaly, earns growing concerns among ophthalmologists for its vision-damaging attribute. The incidence of PCG varies among races and geographic regions and is mostly genetically associated. Theories have been posed in attempt to address the etiology of this congenital maldevelopment and in the meanwhile providing evidence for feasibility of PCG surgeries. In regard to the clinical aspects of this entity, both the clinical characteristics and general principals of management are introduced, with angle surgeries highlighted for clarifying details including their success rates, key points for a successful surgical intervention, postoperative management, and follow-up strategies. Taking patients' vision-associated quality of life into consideration, we stressed that further perceptual learning and low vision rehabilitation are momentous. However, much has yet to be elucidated in respect of the truly comprehensive pathogenesis underneath as well as means by which clinical outcomes of PCG can be further improved. We are now looking forward to innovative therapeutic approaches like gene therapy in specific genes in the future, with the hope of improving their life-long visual quality in those young patients., Competing Interests: The authors declare that there are no conflicts of interest in this paper., (Copyright: © 2022 Taiwan J Ophthalmol.)

The effective area method is described to design high-efficiency multiplayer diffractive optical elements (MLDOEs) with finite feature sizes for wide wave band. This method is presented with consideration of the shield effect between two elements of MLDOEs, and the optimal surface relief heights of MLDOEs are calculated with the effective area method. Then the comparisons of diffraction efficiency and polychromatic integral diffraction efficiency for MLDOEs with different period widths are described and simulated with the effective area method and scalar diffraction theory (SDT). Finally, the design results of MLDOEs obtained by SDT and the effective area method are compared by a rigorous electromagnetic analysis method, specifically, the finite-difference time-domain method. These results show that the limits of SDT for MLDOEs, ascertain and quantify the greatest sources of the diffraction efficiency loss due to the shield effect. The design results of the effective area method can obtain higher polychromatic integral diffraction efficiency than that of the SDT when the period width of MLDOEs is taken into account.