Two Androstane Derivatives from the Cultures of Fungus Marasmiellus ramealis (Bull.) Singer

Ning-Ning Yang,Qing-Yun Ma,Sheng-Zhuo Huang,Hao-Fu Dai,Zhi-Kai Guo,Zhi-Fang Yu,You-Xing Zhao 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.11

A new androstane derivative, 4β-methyl-15-oxa-14β-androstane-7-ene-4α-carboxylic acid (1) and a known one 4β-methyl-15-oxa-14β-androstane-7-ene-4α-hydroxyl (2) were isolated from the EtOAc extract of the cultures of the fungus Marasmiellus ramealis (Bull.) Singer. Their structures were elucidated on the basis of 1D and 2D NMR as well as MS spectroscopic data analysis. The inhibitory activity of two isolates against acetylcholinesterase (AChE) revealed that compound 1 exhibited definitely inhibitory activity.

Modeling and Analysis of CM Noise Behaviors of Transformers in Power Converters

Fu Kai-Ning,Dai Lin-Shan,Lan Wei 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.1

In isolated power converters, electromagnetic feld coupling inside the transformer signifcantly afects its conducted common mode (CM) characteristics. Special concern must be focused on the sophisticated efects of electromagnetic felds on the high-frequency conducted CM noise behaviors of the transformer. The efective frequency range of the existing transformer CM characteristic modeling approaches cannot cover the frequency range from 150 kHz to 30 MHz. Accurately predicting the high frequency conducted CM behavior of transformers is necessary for electromagnetic compatibility design, which avoids the use of unnecessary time in trial and error. In this paper, the scattering parameter is introduced to investigate the high-frequency CM noise behaviors and conducted mechanism of transformers by fnite element method (FEM) simulation tool, and the sensitive factors generating CM noise and causing nonlinear behaviors in the high-frequency range are determined. Good agreement is achieved between FEM simulation results and the measurement in the range of 150 kHz–30 MHz. The proposed simulation modeling method can accurately predict the electric and magnetic feld distribution variation with frequency inside transformer winding window in the design stage, then the high frequency conducted CM noise behavior can also be efectively predicted.

Two Androstane Derivatives from the Cultures of Fungus Marasmiellus ramealis (Bull.) Singer

Yang, Ning-Ning,Ma, Qing-Yun,Huang, Sheng-Zhuo,Dai, Hao-Fu,Guo, Zhi-Kai,Yu, Zhi-Fang,Zhao, You-Xing Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.11

A new androstane derivative, $4{\beta}$-methyl-15-oxa-$14{\beta}$-androstane-7-ene-$4{\alpha}$-carboxylic acid (1) and a known one $4{\beta}$-methyl-15-oxa-$14{\beta}$-androstane-7-ene-$4{\alpha}$-hydroxyl (2) were isolated from the EtOAc extract of the cultures of the fungus Marasmiellus ramealis (Bull.) Singer. Their structures were elucidated on the basis of 1D and 2D NMR as well as MS spectroscopic data analysis. The inhibitory activity of two isolates against acetylcholinesterase (AChE) revealed that compound 1 exhibited definitely inhibitory activity.

Concomitant Acromioclavicular and Coracoclavicular Ligament Reconstruction with a Duo-Figure-8 Autogenic Graft Wrapping Technique for Treating Chronic Acromioclavicular Separation

Fu-Ting Huang,Kai-Cheng Lin,Chih-Yang Lin,Wei-Ning Chang 대한정형외과학회 2021 Clinics in Orthopedic Surgery Vol.13 No.3

Background: Coracoacromial ligament transfer is the traditional procedure for treating chronic acromioclavicular separation, but it is significantly inferior to ligament reconstruction according to biomechanical and clinical studies. However, ligament reconstruction carries the risk of complications of graft loosening and peri-tunnel fractures. Currently, there is no ligament reconstruction procedure optimal for preventing such complications. The purpose of this study was to describe and retrospectively analyze the clinical and radiological outcomes of a “duo-figure-8” autogenic graft wrapping technique, which was used to concomitantly reconstruct the acromioclavicular and coracoclavicular ligaments. Methods: Preoperative, immediate postoperative, and final follow-up oputcomes were evaluated in 10 enrolled patients. Radiographic outcomes were indicated by the bilateral difference of the coracoclavicular distance (CCD) and overlapping length of the acromioclavicular joint (OLac). Quality of reduction was classified into 4 grades according to bilateral CCD difference into overreduction (< 0 mm), anatomic reduction (0–4 mm), partial loss of reduction (4–8 mm), and recurrent dislocation (> 8 mm). Clinical outcomes were evaluated using the American Shoulder and Elbow Surgeons (ASES) and Constant scores. Results: The mean side-to-side differences for CCD were 11.9 mm (preoperative), −0.1 mm (immediate postoperative), and 3.4 mm (final follow-up); those for OLac were 9.4 mm (preoperative) and 2.7 mm (final follow-up). CCD and OLac outcomes significantly improved at final follow-up (p < 0.05). At the immediate postoperative stage, 6 and 4 patients had overreduction and anatomic reduction, respectively. At final follow-up, 7 and 3 patients had anatomic reduction and partial loss of reduction, respectively. The magnitude of improvement of ASES scores for patients with anatomic reduction and partial loss of reduction (p = 0.20) was 18.1 and 20.0, respectively. The magnitude of improvement of Constant scores in patients with anatomic reduction and partial loss of reduction (p = 0.25) was 19.9 and 22.3, respectively. Conclusions: The technique yielded acceptable functional outcomes in patients with anatomic reduction or partial loss of reduction. The “duo-figure-8” wrapping method—a single autogenic tendon graft passing beneath the coracoid process with a tendonknot fixation over the distal clavicle and looping around the acromion intramedullary—did not increase the risk of peri-tunnel fractures over the clavicle, coracoid process, or acromion.

Experimental Quantification on the Residual Seismic Capacity of Damaged RC Column Members

Chien-Kuo Chiu,Hsin-Fang Sung,Kai-Ning Chi,Fu-Pei Hsiao 한국콘크리트학회 2019 International Journal of Concrete Structures and M Vol.13 No.7

To quantify the post-earthquake residual seismic capacity of reinforced concrete (RC) column members, experimental data for 6 column specimens with flexural, flexural–shear and shear failure modes are used to derive residual seismic capacity of damaged RC column members for specified damage states in this work. Besides of the experiment data, some related researches are also investigated to suggest the reduction factors of strength, stiffness and energy dissipation capacity for damaged RC column members, respectively. According to the damage states of RC columns, their corresponding seismic reduction factors are suggested herein. Taking an RC column with the flexural–shear failure for an example, its reductions factors of strength, stiffness and energy dissipation capacity are 0.5, 0.6 and 0.1, respectively. This work also proposes the seismic performance assessment method for the residual seismic performance of earthquake-damaged RC buildings. In the case study, this work selects one actual earthquake-damaged school building to demonstrate the post-earthquake assessment of seismic performance for a damaged RC building.

Experimental Quantification on the Residual Seismic Capacity of Damaged RC Column Members

Chien-Kuo Chiu,Hsin-Fang Sung,Kai-Ning Chi,Fu-Pei Hsiao 한국콘크리트학회 2019 International Journal of Concrete Structures and M Vol.13 No.3

To quantify the post-earthquake residual seismic capacity of reinforced concrete (RC) column members, experimental data for 6 column specimens with flexural, flexural–shear and shear failure modes are used to derive residual seismic capacity of damaged RC column members for specified damage states in this work. Besides of the experiment data, some related researches are also investigated to suggest the reduction factors of strength, stiffness and energy dissipation capacity for damaged RC column members, respectively. According to the damage states of RC columns, their corresponding seismic reduction factors are suggested herein. Taking an RC column with the flexural–shear failure for an example, its reductions factors of strength, stiffness and energy dissipation capacity are 0.5, 0.6 and 0.1, respectively. This work also proposes the seismic performance assessment method for the residual seismic performance of earthquake-damaged RC buildings. In the case study, this work selects one actual earthquake-damaged school building to demonstrate the post-earthquake assessment of seismic performance for a damaged RC building.