Rapid Predictions for Lower-Order Dynamics of Machine Tools Based on the Rigid Multipoint Constraints

Yiwei Ma,Yanling Tian,Xianping Liu 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.3

This study presents a rapid predicting method for lower-order dynamic performances of machine tools. Firstly, the governing equation of motion of the component substructure is obtained drawing on the dynamic condensation from the finite element analysis. Secondly, employing the rigid multipoint constraints at the joint and interface level, the improved reduced dynamic model of component substructures is formulated, resulting in a minimum set of generalized coordinates for external nodes. Then, utilizing the screw theory, the local stiffness mapping between joint and interfaces is illustrated. This is followed by merging the component and joint substructures, resulting in the reduced dynamic model of the entire machine tool. The proposed model is hugely efficient for predicting the distributions of dynamic performances within the entire workspace and guiding the optimal functional design under the framework of virtual machine tools. Finally, a comparison study on a box-in-box type precision horizontal machine tool shows that the lower-order dynamics predicted within the proposed approach have the same trend as those obtained by a complete order finite element model. The experimental modal analysis test shows that the errors of natural frequencies between the proposed model and experiments are lower than 15.61%, demonstrating the effectiveness and accuracy of the proposed model.

Gut Microbiota Dysbiosis Correlates With Long COVID-19 at One-Year After Discharge

Zhang Dongmei,Zhou Yaya,Ma Yanling,Chen Ping,Tang Jian,Yang Bohan,Li Hui,Liang Mengyuan,Xue YuE,Liu Yao,Zhang Jianchu,Wang Xiaorong 대한의학회 2023 Journal of Korean medical science Vol.38 No.15

Background: Long coronavirus disease 2019 (COVID-19) in recovered patients (RPs) is gradually recognized by more people. However, how long it will last and the underlining mechanism remains unclear. Methods: We conducted a prospective follow-up study to evaluate the long-term symptoms and clinical indices of RPs at one-year after discharge from Union Hospital, Wuhan, China between December 2020 to May 2021. We also performed the 16S rRNA sequencing of stool samples from RPs and healthy controls (HCs) and analyzed the correlation between the gut microbiota and long COVID-19. Results: In total, 187 RPs were enrolled, among them, 84 (44.9%) RPs reported long COVID-19 symptoms at one-year after discharge. The most common long-term symptoms were cardiopulmonary symptoms, including chest tightness after activity (39/187, 20.9%), palpitations on exercise (27/187, 14.4%), sputum (21/187, 11.2%), cough (15/187, 8.0%) and chest pain (13/187, 7.0%), followed by systemic symptoms including fatigue (34/187, 18.2%) and myalgia (20/187, 10.7%), and digestive symptoms including constipation (14/187, 7.5%), anorexia (13/187, 7.0%), and diarrhea (8/187, 4.3%). Sixty-six (35.9%) RPs presented either anxiety or depression (42/187 [22.8%] and 53/187 [28.8%] respectively), and the proportion of anxiety or depression in the long symptomatic group was significantly higher than that in the asymptomatic group (41/187 [50.6%] vs. 25/187 [24.3%]). Compared with the asymptomatic group, scores of all nine 36-Item Short Form General Health Survey domains were lower in the symptomatic group (all P < 0.05). One hundred thirty RPs and 32 HCs (non-severe acute respiratory syndrome coronavirus 2 infected subjects) performed fecal sample sequencing. Compared with HCs, symptomatic RPs had obvious gut microbiota dysbiosis including significantly reduced bacterial diversities and lower relative abundance of short-chain fatty acids (SCFAs)-producing salutary symbionts such as Eubacterium_hallii_group, Subdoligranulum, Ruminococcus, Dorea, Coprococcus, and Eubacterium_ventriosum_group. Meanwhile, the relative abundance of Eubacterium_hallii_group, Subdoligranulum, and Ruminococcus showed decreasing tendencies between HCs, the asymptomatic group, and the symptomatic group. Conclusion: This study demonstrated the presence of long COVID-19 which correlates with gut microbiota dysbiosis in RPs at one-year after discharge, indicating gut microbiota may play an important role in long COVID-19.

Improving the Color Gamut of a Liquid-crystal Display by Using a Bandpass Filter

Yan Sun,Chi Zhang,Yanling Yang,Hongmei Ma,Yubao Sun 한국광학회 2019 Current Optics and Photonics Vol.3 No.6

To improve the color gamut of a liquid-crystal display (LCD), we propose a bandpass filter that is added to the backlight unit to optimize the backlight spectrum. The bandpass filter can only transmit red, green and blue light in the visible range, while reflecting the unwanted light. We study the optical properties of the bandpass filter using the transfer-matrix method, and the effect of the bandpass filter on the color gamuts of LCDs is also investigated. When a bandpass filter based on a 5-layer configuration comprising low and high refractive indices ((HL) 2 H) is used in phosphor-converted white-light-emitting diode (pc-WLED), K 2 SiF 6 :Mn 4+ (KSF-LED), and quantum-dot (QD) backlights, the color gamuts of the LCDs improve from 72% to 95.3% of NTSC, from 92% to 106.7% of NTSC, and from 104.3% to 112.2% of NTSC respectively. When the incident angle of light increases to 30°, the color gamuts of LCDs with pc-WLED and KSF-LED backlights decrease by 2.9% and 1% respectively. For the QD backlight, the color gamut almost does not change. When the (HL) 2 H structure is coated on the diffusion film, the color gamut can be improved to 92.6% of NTSC (pc-WLED), 105.6% of NTSC (KSF-LED), and 111.9% of NTSC (QD). The diffusion film has no obvious effect on the color gamut. The results have an important potential application in wide-color-gamut LCDs.

Solvent extraction of Fe3+ from the hydrochloric acid route phosphoric acid by D2EHPA in kerosene

Yang Jin,Yujing Ma,Yanling Weng,Xuhong Jia,Jun Li 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

It is necessary to remove Fe3+ from the hydrochloric acid route phosphoric acid before it is purified by trin-butyl phosphate (TBP), otherwise the final product will fail because of the excessive iron content. Di-(2-ethylhexyl) phosphoric acid (D2EHPA, HA) is effective for Fe3+ extraction. Therefore, the solvent extraction of Fe3+ from the HCl-route phosphoric acid by D2EHPA in kerosene is investigated. The effects of the extraction time, temperature and concentrations of phosphoric acid, D2EHPA, calcium chloride and Fe3+ on the extraction process are studied. The mechanism of the extraction is explained and the extracted species is demonstrated to be FeClA2 4HA. D2EHPA has a high efficiency for Fe3+ extraction from the synthesis and actual HCl-route phosphoric acid with extraction percent of 98.61% and 96.50%, respectively via a cross-current 3-stage extraction. The loaded organic phase is effectively stripped (99.9%) using 6 mol/L hydrochloric acid. The extractant also has a high stability under a closed operation condition. D2EHPA can serve as an adequate extractant for the extraction of Fe3+ from the HCl-route phosphoric acid.

Application of molecular dynamics simulation in self-assembled cancer nanomedicine

Xueli Xu,Ao Liu,Shuangqing Liu,Yanling Ma,Xinyu Zhang,Meng Zhang,Jinhua Zhao,Shuo Sun,Xiao Sun 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Self-assembled nanomedicine holds great potential in cancer theragnostic. The structures and dynamics of nanomedicine can be affected by a variety of non-covalent interactions, so it is essential to ensure the self-assembly process at atomic level. Molecular dynamics (MD) simulation is a key technology to link microcosm and macroscale. Along with the rapid development of computational power and simulation methods, scientists could simulate the specific process of intermolecular interactions. Thus, some experimental observations could be explained at microscopic level and the nanomedicine synthesis process would have traces to follow. This review not only outlines the concept, basic principle, and the parameter setting of MD simulation, but also highlights the recent progress in MD simulation for self-assembled cancer nanomedicine. In addition, the physicochemical parameters of self-assembly structure and interaction between various assembled molecules under MD simulation are also discussed. Therefore, this review will help advanced and novice researchers to quickly zoom in on fundamental information and gather some thoughtprovoking ideas to advance this subfield of self-assembled cancer nanomedicine.

Coactosin-like protein 1 inhibits neuronal migration during mouse corticogenesis

Guohong Li,Yupeng Yin,Jiong Chen,Yanle Fan,Juhong Ma,Yingxue Huang,Chen Chen,Pengxiu Dai,Shulin Chen,Shanting Zhao 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.1

Coactosin-like protein 1 (Cotl1), a member of the actin-depolymerizing factor (ADF)/cofilin family, was first purified from a soluble fraction of Dictyostelium discoideum cells. Neuronal migration requires cytoskeletal remodeling and actin regulation. Although Cotl1 strongly binds to F-actin, the role of Cotl1 in neuronal migration remains undescribed. In this study, we revealed that Cotl1 overexpression impaired migration of both early- and late-born neurons during mouse corticogenesis. Moreover, Cotl1 overexpression delayed, rather than blocked, neuronal migration in late-born neurons. Cotl1 expression disturbed the morphology of migrating neurons, lengthening the leading processes. This study is the first to investigate the function of Cotl1, and the results indicate that Cotl1 is involved in the regulation of neuronal migration and morphogenesis.

Expression of Neurotrophin 4 and Its Receptor Tyrosine Kinase B in Reproductive Tissues during the Follicular and Luteal Phases in Cows

Sun, Yongfeng,Li, Chunjin,Sun, Yanling,Chen, Lu,Liu, Zhuo,Ma, Yonghe,Wang, Chunqiang,Zhang, Wei,Zhou, Xu Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.3

The neurotrophins, required for the survival and differentiation of the nervous system, are known to be important for the development of the reproductive tissues. However, the signals initiating the growth of follicles, gamete development, and transport and the development of zygote in the reproductive system of cows remain ambiguous. The purpose of the present study was to identify the transcripts and proteins of Neurotrophin 4 (NT4) and its receptor tyrosine kinase B (TrkB) in bovine reproductive tissues. The transcripts and immunoreactivity of NT4 and TrkB proteins were detected by reverse transcription polymerase chain reaction and western blot analysis. Using immunohistochemistry, the specific immunoreactivity of NT4 and TrkB were detected in the oocytes of primordial follicles and in the growing primary follicles. The NT4 and TrkB immunoreactivity was predominantly observed in granulosa cells, cumulus granulosa cells, cumulus oocyte complexes, theca cells of mature follicles, as well as in the oviduct epithelial cells, uterine gland cell, and epithelium cells of the uterus during the follicular and luteal phases in cows. Expressions of NT4 and TrkB mRNAs were not significantly different among the ovary, oviduct, and uterus of the follicular phase. For the luteal phase, the expression of NT4 mRNA in the ovary was significantly higher than that in the oviduct and uterus, and the expression of TrkB mRNA in the oviduct was significantly higher than that in the ovary and uterus, as determined by fluorescence quantitative reverse transcription polymerase chain reaction. The expression of NT4 mRNA was significantly higher than that of TrkB mRNA in the ovary and uterus, whereas NT4 mRNA expression was lower than that of TrkB mRNA in the oviduct during the luteal phase. The present study hypothesizes that NT4 participates in the regulation of both gonads and extra-gonadal reproductive tissues in cows.

Enhanced postoperative cancer therapy by iron-based hydrogels

Haomeng Zhang,Meng Zhang,Xinyu Zhang,Yuan Gao,Yanling Ma,Hongyu Chen,Jipeng Wan,Changzhong Li,Fei Wang,Xiao Sun 한국생체재료학회 2022 생체재료학회지 Vol.26 No.2

Surgical resection is a widely used method for the treatment of solid tumor cancers. However, the inhibition of tumor recurrence and metastasis are the main challenges of postoperative tumor therapy. Traditional intravenous or oral administration have poor chemotherapeutics bioavailability and undesirable systemic toxicity. Polymeric hydrogels with a three-dimensional network structure enable on-site delivery and controlled release of therapeutic drugs with reduced systemic toxicity and have been widely developed for postoperative adjuvant tumor therapy. Among them, because of the simple synthesis, good biocompatibility, biodegradability, injectability, and multifunctionality, ironbased hydrogels have received extensive attention. This review has summarized the general synthesis methods and construction principles of iron-based hydrogels, highlighted the latest progress of iron-based hydrogels in postoperative tumor therapy, including chemotherapy, photothermal therapy, photodynamic therapy, chemo-dynamic therapy, and magnetothermal-chemical combined therapy, etc. In addition, the challenges towards clinical application of iron-based hydrogels have also been discussed. This review is expected to show researchers broad perspectives of novel postoperative tumor therapy strategy and provide new ideas in the design and application of novel iron-based hydrogels to advance this sub field in cancer nanomedicine.

High expression of HOXC6 predicts a poor prognosis and induces proliferation and inflammation in multiple myeloma cells

Li Zhihua,Wang Yaru,Hou Xiaoxu,Guo Luyao,Li Yanling,Ma Yanping,Ma Yanping 한국유전학회 2023 Genes & Genomics Vol.45 No.7

Background Multiple myeloma (MM) is a common blood system malignance accompanied by monoclonal plasma cell hyperplasia. Homeobox C6 (HOXC6) acts as an oncogene in various cancers, but its function on MM is elusive. Objective The role of HOXC6 on MM development was clarified in this study. Methods HOXC6 expression and its clinical significance were determined in the peripheral blood samples collected from forty MM patients and thirty healthy adult volunteers. The overall survival was evaluated by Kaplan-Meier analysis with the log-rank test. Cell viability, proliferation and apoptosis were measured by CCK-8, EdU assay and Flow cytometry in U266 and MM.1R cells. Tumor growth was estimated by a xenograft assay. The apoptosis of tumor tissues was evaluated using TUNEL staining. The protein level in tissues was tested by immunohistochemistry. Results The HOXC6 expression was elevated in MM and high HOXC6 level was associated with the poor overall survival of MM. Besides, the HOXC6 expression was associated with hemoglobin level and ISS stage. Furthermore, silencing HOXC6 suppressed cell proliferation, induced cell apoptosis, and restrained the secretion of inflammatory factors (TNF-α, IL-6, and IL-8) in MM cells through inactivating the NF-κB pathway. Moreover, silencing HOXC6 suppressed the tumor growth of MM, the inflammatory factors levels, and the activation of NF-κB pathway but enhanced apoptosis in vivo. Conclusion HOXC6 was elevated in MM and associated with poor survival. Knockdown of HOXC6 suppressed proliferation, inflammation and tumorigenicity of MM cells via inactivating the NF-κB pathway. HOXC6 may be a meaningful target for MM therapy.