Syntheses, Structures, and Characterization of Quaternary Tellurites, Li₃MTe₄O₁₁ (M = Al, Ga, and Fe)

Lü,, Minfeng,Jo, Hongil,Oh, Seung-Jin,Lee, Suheon,Choi, Kwang-Yong,Yu, Yang,Ok, Kang Min ACS AMERICAN CHEMICAL SOCIETY 2017 Inorganic Chemistry Vol.56 No.10

<P>Three new quaternary lithium metal tellurites, Li3MTe4O11 (M = Al, Ga, and Fe), have been synthesized through hydrothermal and solid-state reactions by heating a mixture of LiOH center dot H2O, TeO2, and M2O3. The structures of the title compounds have been determined by single-crystal and powder X-ray diffraction. Li3MTe4O11 reveal three-dimensional (3D) frameworks that consist of MO6 octahedra, TeO3 trigonal pyramids, and TeO4 polyhedra. The variable coordination mode of Te4+ within the framework leads to the formation of 1D channels that host Li+ cations on both tetrahedral and octahedral sites. The bulk and grain boundary Li+ ion conductivities for a Li3FeTe4O11 pellet in open air are estimated to be 1.0 x 10(-4) and 2.7 x 10(-6) S cm(-1), respectively, at room temperature from the impedance profile analysis. A lower activation energy of 19.9 kJ mol(-1) is obtained for the system, which is similar to that of Li10GeP2S12 (24 kJ mol(-1)). Detailed characterizations such as thermal, spectroscopic, and magnetic properties for the reported materials are also reported.</P>

Effects of α-Si₃N₄ seeds and sintering additives on properties of porous silicon nitride ceramics fabricated by carbothermal reduction

Yuan Lu,Ji-Qiang Gao,Jian-feng Yang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.6

In this paper, porous Si3N4 ceramics were fabricated by carbothermal reduction between silicon dioxide and carbon [1]. The influences of α-Si3N4 seeds and sintering additives on the microstructure and mechanical properties of porous Si3N4 ceremics were investigated. XRD analysis proved the complete formation of a single-phase β-Si3N4. SEM analysis showed that the resultant porous Si3N4 ceramics had a fine microstructure and a uniform pore structure. The sintered sample with Lu2O3 as sintering additive showed finer, higher aspect ratio β-Si3N4 grains. The addition of Eu2O3 accelerated the densification of porous Si3N4 ceramics, decreased the porosity and increased the flexural strength. The addition of α-Si3N4 seeds accelerated the formation of the α-Si3N4 phase at a low temperature and the α-β phase transformation process at a high temperature. With an increase in the α-Si3N4 seeds content, the porosity decreased, and the flexural strength increased accordingly. In this paper, porous Si3N4 ceramics were fabricated by carbothermal reduction between silicon dioxide and carbon [1]. The influences of α-Si3N4 seeds and sintering additives on the microstructure and mechanical properties of porous Si3N4 ceremics were investigated. XRD analysis proved the complete formation of a single-phase β-Si3N4. SEM analysis showed that the resultant porous Si3N4 ceramics had a fine microstructure and a uniform pore structure. The sintered sample with Lu2O3 as sintering additive showed finer, higher aspect ratio β-Si3N4 grains. The addition of Eu2O3 accelerated the densification of porous Si3N4 ceramics, decreased the porosity and increased the flexural strength. The addition of α-Si3N4 seeds accelerated the formation of the α-Si3N4 phase at a low temperature and the α-β phase transformation process at a high temperature. With an increase in the α-Si3N4 seeds content, the porosity decreased, and the flexural strength increased accordingly.

Dynamics analysis of novel parallel manipulator with one central rotational actuator and four translational actuators

Yang Lu,Yi Lu,Yang Liu,Bo Hu,Yufeng Gong 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.6

A dynamics analysis of a novel parallel manipulator with one central rotational actuator and four translational actuators is conducted. A 3D model of the parallel manipulator is constructed and its characteristics and DoF are analyzed. The kinematics formulae are derived for solving the displacement, velocity and acceleration of the moving links. The dynamics formulae are derived for solving the inertial wrench of the moving links, the dynamic active forces along the active limbs, the dynamic active torque applied on a central active leg, and the dynamic constrained force exerted on the central active leg. A theoretical numerical example is given to solve the kinematics and dynamics solutions, and the theoretical solutions are verified by the simulation mechanism in Matlab. Finally, a reachable workspace of the novel parallel manipulator is constructed using CAD variation geometry.

Maintaining Drosha expression with Cdk5 inhibitors as a potential therapeutic strategy for early intervention after TBI

Huang Lu,Xia Li,Nie Tiejian,Cui Bozhou,Lu Jianjun,Lu Fangfang,Fan Feiyan,Ren Dongni,Lu Yuan,Gao Guodong,Yang Qian 생화학분자생물학회 2024 Experimental and molecular medicine Vol.56 No.-

Traumatic brain injury (TBI) is a major cause of death and disability in adults. The pathological process of TBI involves a multifactorial cascade in which kinases have been proven contribute to interactions between relevant factors and amplification of signaling cascades. Cyclin-dependent kinase 5 (Cdk5) is a promising kinase that has been implicated in various brain disorders, including TBI. However, the mechanism by which Cdk5 induces neuronal damage remains unclear. Here, we show for the first time that Drosha, a key enzyme in microRNA biogenesis, is a pivotal substrate of abnormally activated Cdk5. Cdk5-mediated phosphorylation decreases Drosha expression and exacerbates nerve injury in TBI. We proved that maintaining Drosha expression via the administration of repurposed Cdk5 inhibitors that were previously studied in clinical trials is a promising approach for the early treatment of TBI. Together, our work identifies Drosha as a novel target for neuroprotective strategies after TBI and suggests Cdk5-mediated regulation of Drosha expression as a potential therapeutic strategy for early TBI intervention.

Striatal Dopamine Transporter Availability is Associated with Sleep Disturbance among Patients with Bipolar I Disorder: A Single-photon Emission Computed Tomography Study Using [99mTc] TRODAT-1

Tsung-Hua Lu(Tsung-Hua Lu),Shih-Hsien Lin(Shih-Hsien Lin),Huai-Hsuan Tseng(Huai-Hsuan Tseng),Yen Kuang Yang(Yen Kuang Yang),Nan Tsing Chiu(Nan Tsing Chiu),Po See Chen(Po See Chen) 대한정신약물학회 2022 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.20 No.4

Objective: Bipolar disorder (BD) is characterized by the poor sleep quality. Whether the striatal dopamine transporter (DAT) availability is related to sleep quality among patients with BD is unclear. Methods: Fifty-three euthymic patients with BD (24 BD-I and 29 BD-II) and sixty-eight healthy controls were enrolled. The Chinese Version of the Pittsburgh Sleep Quality Index (PSQI) was used, and the availability of DAT was assessed by single-photon emission computed tomography (SPECT) using [99mTc] TRODAT-1. Results: The sleep disturbance component of the PSQI was significantly associated with the level of DAT availability among patients with BD. Conclusion: The striatal dopaminergic activity that contributes to resilience to adversity was associated with sleep pattern among patients with BD.

Harm Avoidance is Correlated with the Reward System in Adult Patients with Attention Deficit Hyperactivity Disorder: A Functional Magnetic Resonance Imaging Study

Tsung-Hua Lu(Tsung-Hua Lu),Shih-Hsien Lin(Shih-Hsien Lin),Mei Hung Chi(Mei Hung Chi),Ching-Lin Chu(Ching-Lin Chu),Dong-Yu Yang(Dong-Yu Yang),Wei Hung Chang(Wei Hung Chang),Po See Chen(Po See Chen),Yen 대한정신약물학회 2023 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.21 No.1

Objective: Hypoactivity in the reward system among patients with attention deficit hyperactivity disorder (ADHD) is a well-known phenomenon. Whether the activity in the reward pathway is related to harm avoidance, such as in sensitivity to punishment, is unclear. Evidence regarding the potential difference between ADHD patients and controls in terms of this association is scarce. Methods: Event-related functional magnetic resonance imaging was conducted on subjects performing the Iowa gambling test. Fourteen adults with ADHD and 14 controls were enrolled in the study. Results: Harm avoidance was found to be positively correlated with the activities of the bilateral orbitofrontal cortex and right insula in individuals with ADHD. A group difference was also confirmed. Conclusion: Understanding the roles of harm avoidance and brain activation during risk tasks is important.

Fenofibrate Increases Radiosensitivity in Head and Neck Squamous Cell Carcinoma via Inducing G2/M Arrest and Apoptosis

Liu, Jia,Ge, Yang-Yang,Zhu, Hong-Cheng,Yang, Xi,Cai, Jing,Zhang, Chi,Lu, Jing,Zhan, Liang-Liang,Qin, Qin,Yang, Yan,Yang, Yue-Hua,Zhang, Hao,Chen, Xiao-Chen,Liu, Zhe-Ming,Ma, Jian-Xin,Cheng, Hong-Yan,S Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Radiation therapy is an important treatment for head and neck squamous cell carcinoma (HNSCC). However, how to promote radiation sensitivity in HNSCC remains a challenge. This study aimed to investigate the radiosensitizing effects of fenofibrate on HNSCC and explore the underlying mechanisms. HNSCC cell lines CNE-2 and KB were subjected to ionizing radiation (IR), in the presence or absence of fenofibrate treatment. Cell growth and survival, apoptosis and cell cycle were evaluated. In addition, CNE-2 cells were xenografted into nude mice and subjected to IR and/or fenofibrate treatment. The expression of cyclinB and CDK1 was detected by Western blotting. Our results showed that fenofibrate efficiently radiosensitized HNSCC cells and xenografts in mice, and induced apoptosis and G2/M arrest via reducing the activity of the CDK1/cyclinB1 kinase complex. These data suggest that fenofibrate could be a promising radiosensitizer for HNSCC radiotherapy.

Development and Validation of 18F-FDG PET/CT-Based Multivariable Clinical Prediction Models for the Identification of Malignancy-Associated Hemophagocytic Lymphohistiocytosis

Yang Xu,Lu Xia,Liu Jun,Kan Ying,Wang Wei,Zhang Shuxin,Liu Lei,Li Jixia,Yang Jigang 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.4

Objective: 18F-fluorodeoxyglucose (FDG) PET/CT is often used for detecting malignancy in patients with newly diagnosed hemophagocytic lymphohistiocytosis (HLH), with acceptable sensitivity but relatively low specificity. The aim of this study was to improve the diagnostic ability of 18F-FDG PET/CT in identifying malignancy in patients with HLH by combining 18F-FDG PET/CT and clinical parameters. Materials and Methods: Ninety-seven patients (age ≥ 14 years) with secondary HLH were retrospectively reviewed and divided into the derivation (n = 71) and validation (n = 26) cohorts according to admission time. In the derivation cohort, 22 patients had malignancy-associated HLH (M-HLH) and 49 patients had non-malignancy-associated HLH (NM-HLH). Data on pretreatment 18F-FDG PET/CT and laboratory results were collected. The variables were analyzed using the Mann-Whitney U test or Pearson’s chi-square test, and a nomogram for predicting M-HLH was constructed using multivariable binary logistic regression. The predictors were also ranked using decision-tree analysis. The nomogram and decision tree were validated in the validation cohort (10 patients with M-HLH and 16 patients with NM-HLH). Results: The ratio of the maximal standardized uptake value (SUVmax) of the lymph nodes to that of the mediastinum, the ratio of the SUVmax of bone lesions or bone marrow to that of the mediastinum, and age were selected for constructing the model. The nomogram showed good performance in predicting M-HLH in the validation cohort, with an area under the receiver operating characteristic curve of 0.875 (95% confidence interval, 0.686–0.971). At an appropriate cutoff value, the sensitivity and specificity for identifying M-HLH were 90% (9/10) and 68.8% (11/16), respectively. The decision tree integrating the same variables showed 70% (7/10) sensitivity and 93.8% (15/16) specificity for identifying M-HLH. In comparison, visual analysis of 18F-FDG PET/CT images demonstrated 100% (10/10) sensitivity and 12.5% (2/16) specificity. Conclusion: 18F-FDG PET/CT may be a practical technique for identifying M-HLH. The model constructed using 18F-FDG PET/CT features and age was able to detect malignancy with better accuracy than visual analysis of 18F-FDG PET/CT images.

Effects of Selenizing Modification on Characteristics and Antioxidant Activities of Inonotus obliquus Polysaccharide

Yang Hu,Shanyi Shi,Lu Lu,Chunying Teng,Sumei Yu,Xin Wang,Min Yu,Jinsong Liang,Juanjuan Qu 한국고분자학회 2017 Macromolecular Research Vol.25 No.3

Excessive reactive oxygen species is implicated in the etiology and pathology of many acute and chronic diseases. Selenium acts as an antioxidant and stimulates the creation of more antioxidants. Selenizing modification polysaccharides potentiate the physiological and pharmacological activities of selenium and polysaccharide. In this study, Inonotus obliquus polysaccharide (IOP) extracted from cultured mycelia was modified into Se-IOP by HNO3- Na2SeO3 method. The characteristics and antioxidant activity of IOP and Se-IOP were comparatively investigated. The result showed that polysaccharide content of purified IOP was 98.9%. The selenium content of Se-IOP was 0.71 mg/g. Both IOP and Se-IOP were homogeneous polysaccharides with a molecular weight of 37.354 and 28.071 kDa, respectively depicted in high performance gel permeation chromatogram (HPGPC). Moreover, both IOP and Se- IOP were composed of Man, Glu, and Gal with a molar ratio of 7.7:32.6:23.3 and 8.3:32.1:22.7, respectively determined by high performance liquid chromatography (HPLC). The characteristic absorption peak of O-Se-O, Se=O and C-O-Se appeared at 1026.75, 772.82, and 652.29 cm-1 respectively in FT-IR spectrum of Se-IOP indicating the success of selenylation. NMR spectrum further confirmed the anomeric carbon signals and chemical shifts in IOP and Se-IOP. These variations induced by selenylation may lead to a higher antioxidant activity of Se-IOP on scavenging hydroxyl, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and superoxide radical than that of IOP. Furthermore, Se- IOP treatment could also reduce oxidant damage by decreasing the level of malondialdehyde (MDA) and increasing the activities of superoxidedismutase (SOD) and GSH-Px in mice.

A New Green Clustering Algorithm for Energy Efficiency in High-Density WLANs

( Yang Lu ),( Xuezhi Tan ),( Yun Mo ),( Lin Ma ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.2

In this paper, a new green clustering algorithm is proposed to be as a first approach in the framework of an energy efficient strategy for centralized enterprise high-density WLANs. Traditionally, in order to maintain the network coverage, all the APs within the WLAN have to be powered-on. Nevertheless, the new algorithm can power-off a large proportion of APs while the coverage is maintained as its always-on counterpart. The two main components of the new approach are the faster procedure based on K-means and the more accurate procedure based on Evolutionary Algorithm (EA), respectively. The two procedures are processes in parallel for different designed requirements and there is information interaction in between. In order to implement the new algorithm, EA is applied to handle the optimization of multiple objectives. Moreover, we adapt the method for selection and recombination, and then introduce a new operator for mutation. This paper also presents simulations in scenarios modeled with ray-tracing method and FDTD technique, and the results show that about 67% to 90% of energy consumption can be saved while it is able to maintain the original network coverage during periods when few users are online or the traffic load is low.