스파럴 서보 트랙 라이팅을 위한 기준 입력과 제어기 설계

Simin Chen,Hyun Jae Kang,Seung-Hi Lee,Chung Choo Chung 제어로봇시스템학회 2011 제어로봇시스템학회 국내학술대회 논문집 Vol.2011 No.5

Spiral servo track writing (SSTW) is the writing method which writes servo information based on spiral pattern. One important factor of SSTW is the setup time of acceleration/deceleration region. In this paper, we design a reference input and electrical spring controller to reduce the setup time. Reference input is used to suppress the resonance excitation caused by fast seeking and settling motion. Current estimator with integral control is employed as the base controller, which compensates the bias force in the SSTW system. However, integral control has a drawback of worsening the setup time with respect to SSTW, so we propose an electrical spring controller to overcome this problem. The performance of the proposed strategy is verified by simulation which shows the setup time is reduced by 36% with electrical spring in combination with the base controller.

Quantitative Analysis of Parotid Gland Secretion Function in Sjögren’s Syndrome Patients with Dynamic Magnetic Resonance Sialography

Simin Liu,Weiwei Chen,Min Wang,Tong Wu,Lingli Dong,Chu Pan,Wenzhen Zhu 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.3

Objective: To evaluate the secretory function of parotid glands by dynamic magnetic resonance (MR) sialography and determine the clinical performance of this technique in diagnosing and evaluating Sjögren’s syndrome (SS) patients. Materials and Methods: This study enrolled 29 healthy volunteers (25 women and 4 men; mean age, 34.8 ± 6.3 years; age range, 26–47 years) and 25 primary SS (pSS) patients (23 women and 2 men; mean age, 37.7 ± 7.9 years; age range, 25–50 years) with decreased secretory function. The volume of the parotid gland ducts was precisely measured for both groups at single pre- and 6 post-gustatory-stimulated phases. Time-dependent volume change ratio curves were generated, four parameters were derived from the curves: the slope of the increase in the first post-stimulation phase (slope1st), the peak value, the time-to-peak, the total saliva secretion post-stimulation. All values were used to quantitatively evaluate the secretory function of the parotid gland. The repeated measurement analysis, Mann-Whitney U test and receiver operating characteristic curve were applied. Results: Time-dependent volume change ratio curves demonstrated that there is a statistically significant difference between the two groups (F = 8.750; p = 0.005). A quickly increasing curve was shown in the volunteer group, whereas a slowly increasing curve was shown in the pSS patient group. The slope1st, peak value and total saliva secretion post-stimulation of the patient group were significantly lower than those of the volunteer group (p = 0.005, p = 0.003, and p = 0.002, respectively). The timeto-peak between the two groups was not significantly different (p = 0.383). The slope1st can be used as a discriminator to diagnose SS patients (p = 0.015; odds ratio = 4.234; area under the curve = 0.726). Conclusion: Dynamic MR sialography is proven to be an effective method in evaluating salivary gland function and has a great potential in diagnosing and evaluating pSS patients.

Enhanced Mechanical and Processing Property of Styrene-butadiene Rubber Composites with Novel Silica-supported Reactive Processing Additive

Simin Li,Yuanfang Luo,Chen Yongjun,Tiwen Xu,Bangchao Zhong,Zhixin Jia,Demin Jia 한국섬유공학회 2019 Fibers and polymers Vol.20 No.8

To simultaneously improve processing performances of rubber composites and avoid additive-blooming problem,the concept of “supported rubber additives” was introduced and reactive processing additive oleic acid (OA) was chemicallyimmobilized onto the surface of silica to obtain silica-supported processing additive (SiO2-s-OA). In this study, SiO2-s-OAwas uniformly dispersed into styrene-butadiene rubber (SBR) and gained improved interfacial interaction with rubber matrixdue to its good compatibility and the reaction during vulcanization. Consequently, SBR compounds with SiO2-s-OApossessed lower vulcanizing torque and viscosity under high shear frequency, showing improved processing performance. Moreover, the tensile modulus and strength of SBR/SiO2-s-OA could be enhanced by as much as 88.40 % and 11.44 %compared to SBR/SiO2, respectively, which is also higher than SBR/m-SiO2. Taken together, these results indicate that thismethod for the surface treatment of silica to prepare supported rubber additives may be extended for other nanofillers andrubber additives, which has better processing performance and improved mechanical property simultaneously.

Diffusion Tensor Imaging of the Lateral Pterygoid Muscle in Patients with Temporomandibular Joint Disorders and Healthy Volunteers

Liu Simin,Wan Changhua,Li Haosen,Chen Weiwei,Pan Chu 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.2

Objective: This study aimed to explore the feasibility of functional evaluation of the lateral pterygoid muscle (LPM) using diffusion tensor imaging (DTI) in patients with temporomandibular joint disorders (TMDs). Materials and Methods: A total of 119 patients with TMD (23 male and 96 female; mean age ± standard deviation, 41 ± 15 years; 58 bilateral and 61 unilateral involvements for a total of 177 joints) and 20 healthy volunteers (9 male and 11 female; 40 ± 13 years; 40 joints) were included in this prospective study. Based on DTI of the jaw in the resting state, the diffusion parameters, apparent diffusion coefficient (ADC), fractional anisotropy (FA), λ1, λ2, and λ3 of the superior and inferior heads of the LPM (SHLPM and IHLPM) were measured. Patients with TMD with normal disc position (ND), anterior disc displacement with reduction (ADWR), and anterior disc displacement without reduction (ADWOR) were compared. Results: Patients with TMD overall, and ADWR and ADWOR subgroups had significantly higher ADC, λ1, λ2, and λ3 in both the SHLPM and IHLPM than those in volunteers (p < 0.05 for all), whereas the ND subgroup only had significantly higher ADC and λ1 (p < 0.001). Meanwhile, significant differences in FA in the SHLPM and IHLPM were found between volunteers and ADWOR (p = 0.014 and p = 0.037, respectively). Among the three TMD subgroups, except for λ3 and FA in the ADWR subgroup, ADWR and ADWOR subgroups had significantly higher ADC, λ1, λ2, and λ3 and lower FA than those in the ND group (p < 0.050). There was no significant difference in diffusion variables between ADWR and ADWOR. In ADWOR, the osteoarthritis group had significantly higher λ3 and lower FA values in the IHLPM than those in the non-osteoarthritis group. Conclusion: DTI successfully detected functional changes in the LPM in patients with TMD. The unsynchronized diffusivity changes in the LPM in different subgroups of TMD signified the possibility of using diffusion parameters as indicators to identify the severity of LPM hyperfunction at various stages of TMD.

Orthorhombic carbon oC24: A novel topological nodal line semimetal

Li, Zhen-Zhen,Chen, Jia,Nie, Simin,Xu, Lifang,Mizuseki, Hiroshi,Weng, Hongming,Wang, Jian-Tao Elsevier 2018 Carbon Vol.133 No.-

<P><B>Abstract</B></P> <P>We identify by <I>ab initio</I> calculations a stable three-dimensional carbon allotrope that constructed by inserting benzene rings into the carbon-carbon bonds in a previously reported oC8 carbon. This new carbon phase has a 24-atom orthorhombic unit cell in C m m m ( D 2 H 19 ) symmetry and thus termed oC24. Phonon mode analysis confirms its dynamical stable. Total-energy calculations show that it is energetically stable comparable with (5,5) carbon nanotube. Detailed electronic band calculations reveal that oC24 is a topological node-line semimetal with two mirror-inversion symmetric nodal lines that go through the whole Brillouin zone in bulk and a projected surface flat band around the Fermi level. The present results establish a new type of carbon phases and offer insights into their outstanding structural and electronic properties.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A Compact Dual-Band MIMO Antenna for Sub-6 GHz 5G Terminals

Dong Guiting,Huang Jianlin,Lin Simin,Chen Zhizhou,Liu Gui 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.5

In this paper, a dual-band multiple-input-multiple-output (MIMO) antenna is proposed for fifth-generation (5G) wireless communication terminals. The measured -10 dB impedance bandwidths of 380 MHz (3.34–3.72 GHz) and 560 MHz (4.57–5.13 GHz) can cover the 3.4–3.6 GHz and 4.8–5 GHz 5G bands. The single antenna element of this proposed MIMO is composed of an F-shaped feed strip and an inverted L-shaped radiation strip. A defected ground structure is employed to obtain a good isolation performance, whereby the measured isolation between the antenna elements is observed to be larger than 23 dB. The measured total radiation efficiencies at 3.5 GHz and 4.9 GHz are 76.65% and 71.93%, respectively. Besides, the calculated envelope correlation coefficients (ECC) are less than 0.00125 and 0.01164 at the low-frequency and high-frequency bands, respectively. Furthermore, the specific absorption ratio (SAR) analysis of the antenna verifies that it qualifies for 5G terminals.

<i>Plasmodium ovale curtisi</i> and <i>Plasmodium ovale wallikeri</i> in Chinese travelers: Prevalence of novel genotypes of circumsporozoite protein in the African continent

Lu, Feng,Ahmed, Md Atique,Xu, Simin,Xu, Sui,Han, Jin-Hee,Liu, Qianyan,Chen, Jing,Zhu, Guoding,Zhou, Huayun,Cao, Jun,Han, Eun-Taek ELSEVIER 2019 INFECTION GENETICS AND EVOLUTION Vol.70 No.-

<P><B>Abstract</B></P> <P>Imported malaria due to <I>Plasmodium ovale curtisi</I> and <I>P</I>. <I>ovale wallikeri</I> infections from African countries has increased recently (2011–2014) in Chinese travelers. We report novel genotypes, their prevalence and the predominant haplotypes of <I>P</I>. <I>ovale curtisi</I> and <I>P</I>. <I>ovale wallikeri</I> circumsporozoite protein (CSP) from 20 African countries in Chinese travelers. These genotypes should be considered while designing a CSP-based vaccine against <I>P</I>. <I>ovale</I> malaria.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This is the first to report the <I>csp</I> genotypes and their heterogeneity for <I>P. ovale curtisi</I> and <I>P. ovale wallikeri</I> parasites from African countries. </LI> <LI> Ten <I>csp</I> genotypes of <I>P</I>. <I>ovale curtisi</I> and 13 <I>csp</I> genotypes of <I>P</I>. <I>ovale wallikeri</I> based on the arrangement of central repeat motifs were found. </LI> <LI> Fifteen <I>csp</I> haplotypes of <I>P</I>. <I>ovale curtisi</I> and 10 <I>csp</I> haplotypes of <I>P</I>. <I>ovale wallikeri</I> on central repeat motifs were identified. </LI> <LI> These genotypes should be considered while designing a CSP-based vaccine against <I>P</I>. <I>ovale</I> malaria. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Alpha-Hemolysin from Staphylococcus aureus Obstructs Yeast-Hyphae Switching and Diminishes Pathogenicity in Candida albicans

Yu Xiaoyu,Mao Yinhe,Li Guangbo,Wu Xianwei,Xuan Qiankun,Yang Simin,Chen Xiaoqing,Cao Qi,Guo Jian,Guo Jinhu,Wu Wenjuan 한국미생물학회 2023 The journal of microbiology Vol.61 No.2

The use of antibiotics can disrupt the body’s natural balance and increase the susteptibility of patients towards fungal infections. Candida albicans is a dimorphic opportunistic fungal pathogen with niches similar to those of bacteria. Our aim was to study the interaction between this pathogen and bacteria to facilitate the control of C. albicans infection. Alpha-hemolysin (Hla), a protein secreted from Staphylococcus aureus, causes cell wall damage and impedes the yeast–hyphae transition in C. albicans. Mechanistically, Hla stimulation triggered the formation of reactive oxygen species that damaged the cell wall and mitochondria of C. albicans. The cell cycle was arrested in the G0/G1 phase, CDC42 was downregulated, and Ywp1 was upregulated, disrupting yeast hyphae switching. Subsequently, hyphae development was inhibited. In mouse models, C. albicans pretreated with Hla reduced the C. albicans burden in skin and vaginal mucosal infections, suggesting that S. aureus Hla can inhibit hyphal development and reduce the pathogenicity of candidiasis in vivo.

A positive feedback loop of heparanase/ syndecan1/nerve growth factor regulates cancer pain progression

Xiaohu Su,Bingwu Wang,Zhaoyun Zhou,Zixian Li,Song Tong,Simin Chen,Nan Zhang,Su Liu,Maoyin Zhang 대한통증학회 2023 The Korean Journal of Pain Vol.36 No.1

Background: The purpose of this research was to assess the role of heparanase (HPSE)/syndecan1 (SDC1)/nerve growth factor (NGF) on cancer pain from melanoma. Methods: The influence of HPSE on the biological function of melanoma cells and cancer pain in a mouse model was evaluated. Immunohistochemical staining was used to analyze HPSE and SDC1. HPSE, NGF, and SDC1 were detected using western blot. Inflammatory factors were detected using ELISA assay. Results: HPSE promoted melanoma cell viability, proliferation, migration, invasion, and tumor growth, as well as cancer pain, while SST0001 treatment reversed the promoting effect of HPSE. HPSE up-regulated NGF, and NGF feedback promoted HPSE. High expression of NGF reversed the inhibitory effect of HPSE down-regulation on melanoma cell phenotype deterioration, including cell viability, proliferation, migration, and invasion. SST0001 down-regulated SDC1 expression. SDC1 reversed the inhibitory effect of SST0001 on cancer pain. Conclusions: The results showed that HPSE promoted melanoma development and cancer pain by interacting with NGF/SDC1. It provides new insights to better understand the role of HPSE in melanoma and also provides a new direction for cancer pain treatment.

A synthetic host-guest system achieves avidin-biotin affinity by overcoming enthalpy-entropy compensation.

Rekharsky, Mikhail V,Mori, Tadashi,Yang, Cheng,Ko, Young Ho,Selvapalam, N,Kim, Hyunuk,Sobransingh, David,Kaifer, Angel E,Liu, Simin,Isaacs, Lyle,Chen, Wei,Moghaddam, Sarvin,Gilson, Michael K,Kim, Kimo National Academy of Sciences 2007 Proceedings of the National Academy of Sciences Vol.104 No.52

<P>The molecular host cucurbit[7]uril forms an extremely stable inclusion complex with the dicationic ferrocene derivative bis(trimethylammoniomethyl)ferrocene in aqueous solution. The equilibrium association constant for this host-guest pair is 3 x 10(15) M(-1) (K(d) = 3 x 10(-16) M), equivalent to that exhibited by the avidin-biotin pair. Although purely synthetic systems with larger association constants have been reported, the present one is unique because it does not rely on polyvalency. Instead, it achieves its extreme affinity by overcoming the compensatory enthalpy-entropy relationship usually observed in supramolecular complexes. Its disproportionately low entropic cost is traced to extensive host desolvation and to the rigidity of both the host and the guest.</P>