74 results on '"Zhang, Dongyun"'
Search Results
2. A Review on Traditional Processes and Laser Powder Bed Fusion of Aluminum Alloy Microstructures, Mechanical Properties, Costs, and Applications.
- Author
-
Wang, Xin, Zhang, Dongyun, Li, Ang, Yi, Denghao, and Li, Tianci
- Subjects
ALUMINUM alloys ,ALLOY powders ,MICROSTRUCTURE ,ALUMINUM powder ,MANUFACTURING processes ,COMPOSITE materials ,ALUMINUM composites - Abstract
Due to its lightweight, high strength, good machinability, and low cost, aluminum alloy has been widely used in fields such as aerospace, automotive, electronics, and construction. Traditional manufacturing processes for aluminum alloys often suffer from low material utilization, complex procedures, and long manufacturing cycles. Therefore, more and more scholars are turning their attention to the laser powder bed fusion (LPBF) process for aluminum alloys, which has the advantages of high material utilization, good formability for complex structures, and short manufacturing cycles. However, the widespread promotion and application of LPBF aluminum alloys still face challenges. The excellent printable ability, favorable mechanical performance, and low manufacturing cost are the main factors affecting the applicability of the LPBF process for aluminum alloys. This paper reviews the research status of traditional aluminum alloy processing and LPBF aluminum alloy and makes a comparison from various aspects such as microstructures, mechanical properties, application scenarios, and manufacturing costs. At present, the LPBF manufacturing cost for aluminum alloys is 2–120 times higher than that of traditional manufacturing methods, with the discrepancy depending on the complexity of the part. Therefore, it is necessary to promote the further development and application of aluminum alloy 3D printing technology from three aspects: the development of aluminum matrix composite materials reinforced with nanoceramic particles, the development of micro-alloyed aluminum alloy powders specially designed for LPBF, and the development of new technologies and equipment to reduce the manufacturing cost of LPBF aluminum alloy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Cabergoline targets multiple pathways to inhibit PRL secretion and increases stromal fibrosis.
- Author
-
Zhang, Dongyun, Hugo, Willy, Bergsneider, Marvin, Wang, Marilene B, Kim, Won, Han, Karam, Vinters, Harry V, and Heaney, Anthony P
- Subjects
PROLACTINOMA ,PERFORINS ,CYTOTOXIC T cells ,CABERGOLINE ,CELL populations ,SECRETION ,PROGENITOR cells - Abstract
Objective Unravel the potential mechanism(s) of the on- and off-target actions of dopamine agonist therapy in both human prolactinoma tumors and neighboring stromal and immune cells. Design and Methods Five surgically resected prolactinomas (PRLomas) from 3 cabergoline (CBG)-treated patients and 2 treatment-naive patients were analyzed by using single-cell RNA sequencing (scRNA-seq) to compare the cellular composition and transcriptional landscape. Results Six major cell populations, namely tumor (88.2%), immune (5.6%), stromal (4.9%), progenitor cells (0.6%), proliferating cells (0.4%), and erythrocytes (0.2%), were observed. Tumor cells from CBG-treated patients expressed lower levels of genes that regulated hormone secretion, such as SCG2, VGF, TIMP1, NNAT, and CALD1, consistent with the inhibitory effects of CBG on hormone processing and secretion. Interestingly, we also observed an increased number of CD8
+ T cells in the CBG-treated tissues. These cytotoxic CD8+ T cells expressed killing granule components such as perforin and the granzymes GZMB, GNLY, and KLRD1 as well as the inflammatory cytokine CCL5. Immune cell activation of these CD8+ T cells was further analyzed in a compartment-specific manner, and increased CD25 (IL2R) expression was noted in the CD8+ T cells from the CBG-treated samples. Additionally, and confirming prior reports, we noted a higher stromal cell population in the CBG-treated samples. Conclusions Our scRNA-seq studies revealed key differences in the transcriptomic features of CBG-treated and CBG-untreated PRLomas in both tumor and microenvironment cellular constituents, and for the first time, describe the previously unknown activation of CD8+ T cells following CBG treatment, which may play a role in the tumoricidal actions of CBG. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
4. Expression characteristics of the cyp19a1b aromatase gene and its response to 17β-estradiol treatment in largemouth bass (Micropterus salmoides).
- Author
-
Zhang, Dongyun, Tian, Taihang, Han, Linqiang, Du, Jinxing, Zhu, Tao, Lei, Caixia, Song, Hongmei, and Li, Shengjie
- Abstract
To investigate the regulatory role of the cyp19a1b aromatase gene in the sexual differentiation of largemouth bass (Micropterus salmoides, LMB), we obtained the full-length cDNA sequence of cyp19a1b using rapid amplification of cDNA ends technique. Tissue expression characteristics and feedback with 17-β-estradiol (E
2 ) were determined using quantitative real-time PCR (qRT-PCR), while gonad development was assessed through histological section observations. The cDNA sequence of LMB cyp19a1b was found to be1950 base pairs (bp) in length, including a 5′ untranslated region of 145 bp, a 3′ untranslated region of 278 bp, and an open reading frame encoding a protein consisting of 1527 bp that encoded 508 amino acids. The qRT-PCR results indicated that cyp19a1b abundantly expressed in the brain, followed by the gonads, and its expression in the ovaries was significantly higher than that observed in the testes (P < 0.05). After feeding fish with E2 for 30 days, the expression of cyp19a1b in the pseudo-female gonads (XY-F) was significantly higher than that in males (XY-M) (P < 0.05), whereas expression did not differ significantly between XX-F and XY-F fish (P > 0.05). Although the expression of cyp19a1b in XY-F and XX-F fish was not significantly different after 60 days (P>0.05), both exhibited significantly higher levels than that of XY-M fish (P<0.05). Histological sections analysis showed the presence of oogonia in both XY-F and XX-F fish at 30 days, while spermatogonia were observed in XY-M fish. At 60 days, primary oocytes were abundantly observed in both XY-F and XX-F fish, while a few spermatogonia were visible in XY-M fish. At 90 days, the histological sections' results showed that a large number of oocytes were visible in XY-F and XX-F fish. Additionally, the gonads of XY-M fish contained numerous spermatocytes. These results suggest that cyp19a1b plays a pivotal role in the development of ovaries and nervous system development in LMB. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
5. Whole-exome sequencing reveals genetic variants that may play a role in neurocytomas.
- Author
-
Khowal, Sapna, Zhang, Dongyun, Yong, William H, and Heaney, Anthony P.
- Abstract
Objectives: Neurocytomas (NCs) are rare intracranial tumors that can often be surgically resected. However, disease course is unpredictable in many patients and medical therapies are lacking. We have used whole exome sequencing to explore the molecular etiology for neurocytoma and assist in target identification to develop novel therapeutic interventions. Methods: We used whole exome sequencing (WES) to compare the molecular landscape of 21 primary & recurrent NCs to five normal cerebellar control samples. WES data was analyzed using the Qiagen Clinical Insight program, variants of interest (VOI) were interrogated using ConSurf, ScoreCons, & Ingenuity Pathway Analysis Software to predict their potential functional effects, and Copy number variations (CNVs) in the genes of interest were analyzed by Genewiz (Azenta Life Sciences). Results: Of 40 VOI involving thirty-six genes, 7 were pathogenic, 17 likely-pathogenic, and 16 of uncertain-significance. Of seven pathogenic NC associated variants, Glucosylceramidase beta 1 [GBA1 c.703T > C (p.S235P)] was mutated in 5/21 (24%), Coagulation factor VIII [F8 c.3637dupA (p.I1213fs*28)] in 4/21 (19%), Phenylalanine hydroxylase [PAH c.975C > A (p.Y325*)] in 3/21 (14%), and Fanconi anemia complementation group C [FANCC c.1162G > T (p.G388*)], Chromodomain helicase DNA binding protein 7 [CHD7 c.2839C > T (p.R947*)], Myosin VIIA [MYO7A c.940G > T (p.E314*)] and Dynein axonemal heavy chain 11 [DNAH11 c.3544C > T (p.R1182*)] in 2/21 (9.5%) NCs respectively. CNVs were noted in 85% of these latter 7 genes. Interestingly, a Carboxy-terminal domain RNA polymerase II polypeptide A small phosphatase 2 [CTDSP2 c.472G > A (p.E158K)] of uncertain significance was also found in > 70% of NC cases. Interpretation: The variants of interest we identified in the NCs regulate a variety of neurological processes including cilia motility, cell metabolism, immune responses, and DNA damage repair and provide novel insights into the molecular pathogenesis of these extremely rare tumors. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Effect of homogenizing treatment on microstructure and microhardness of GH3536 and GH4169 alloy by selective laser melting.
- Author
-
GENG Shuo, ZHANG Dongyun, LI Jianmin, YI Denghao, CHI Yujing, HUANG Shuai, and ZHANG Xuejun
- Subjects
SELECTIVE laser melting ,MICROHARDNESS ,MICROSTRUCTURE ,CRYSTAL grain boundaries ,LASERS ,VICKERS hardness ,CERAMICS - Abstract
GH3536 and GH4169 nickel-based superalloys are widely used in aerospace engines and other hot-end components. In this paper, GH3536 and GH4169 alloy samples were fabricated by optimizing the process parameters using selective laser melting(SLM), the defect characteristics and microstructure of two alloys, as well as the effects of different homogenization temperatures and holding times on microstructure evolution, average grain size, and properties of two alloys were studied. The defect characteristics and microstructure were investigated by OM, SEM, and EDS, et al. The Vickers hardness meter was used to test the alloy's microhardness. The results indicate that the as-built GH3536 alloy exhibits more defects, including pores, cracks, and lack of fusion, while only pores are present in as-built GH4169 alloy. The melt pool of alloy is eliminated by homogenization treatment, and the grains grow into equiaxed grains. m23C6 are found to distribute within grain boundaries and grain interiors of GH3536 alloy, while NbC are found to distribute within grain boundaries and grain interiors of GH4169 alloy, and the amount of precipitates is significantly reduced with the increase of homogenization temperature. The average grain size of GH3536 alloy is increased by 106.8% from 48.5 -m at 1130 t/1 h to 100.9 m at 1250 t/4 h . The grain size of GH4169 alloy is increased by 53.3% from 57 m at 1080 t/1 h to 87.4 m at 1200 t/4 h.The homogenization treatment of GH3536 alloy and GH4169 alloy results in a significant decrease in microhardness of the former, from 262HV to 180-190HV, while the latter shows a significant increase, from 313HV to 430-450HV. [ABSTRACT FROM AUTHOR]
- Published
- 2024
7. Prognostic Significance of Advanced Age in Patients with T1a Renal Cell Carcinoma Treated by Microwave Ablation: A 16-Year Experience.
- Author
-
Hou, Qidi, Wang, Yaxi, Zhang, Dongyun, Luo, Yanchun, Dong, Linan, Mu, Mengjuan, Yu, Jie, and Liang, Ping
- Subjects
RENAL cell carcinoma ,MATERNAL age ,OLDER patients ,PROPENSITY score matching ,WATCHFUL waiting ,CATHETER ablation - Abstract
Background: Previous studies have failed to investigate the specific effects of advanced age on survival outcomes by considering the Charlson Comorbidity Index (CCI) and age permutation in patients with T1a renal cell carcinoma (T1a RCC) treated by microwave ablation (MWA). Notably, RCC guidelines recommended radiofrequency ablation (RFA) and active surveillance (AS) are both treatment options for elderly T1a RCC, but whether MWA is superior to AS in light of higher heating efficiency and larger ablation zone compared with RFA is not clear. This study aimed to investigate the specific effects of advanced age on survival outcomes of T1a RCC patients stratified by CCI score and indicate better intervention for elderly T1a RCC between MWA and AS. Methods: This was a retrospective study. We retrospectively reviewed 237 patients with T1a RCC who had undergone MWA over the last 16 years. Data were analyzed by Cox regression and Landmark analysis. Interaction tests and propensity score matching were used to account for potential biases. We compared the overall survival (OS) and cancer-specific survival (CSS) rates of patients ≥75 years in our study with corresponding figures from 4251 counterparts undergoing AS in published articles. Results: Using patients <75 years with a CCI ≤2 as a reference, the hazard ratio (HR) and 95% confidence interval (CI) of OS for patients<75 years with a CCI ≥3, patients ≥75 years with a CCI ≤2, and patients ≥75 years with CCI ≥3, were 2.954 (1.139-7.663), 3.48 (1.487-8.146), and 3.357 (1.162-9.698), respectively. The adverse effect of an age ≥75 years on OS was attenuated in patients with a CCI ≥3. The attenuation lasted for 62.5 months of follow-up (P =.017). Notably, advanced age exerted a protective effect on progression-free survival (PFS) in patients with a CCI ≥3, increasing the 8-year PFS from 67.8% to 100% (P =.049). Relative to 1-, 3-, 5-, and 8-year survival data for patients aged ≥75 undergoing AS, the OS rates for 5-year follow-up were always better in MWA. However, beyond 5 years, the OS rates dropped to levels that were similar to AS. Conclusions: Advanced age exerts adverse effects and significantly protective effects on OS and PFS, respectively, in T1a RCC patients with a CCI ≥ 3. According to our study, elderly patients with T1a RCC underwent radical MWA may yield a better medium-term OS relative to AS. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
8. Influence of the properties of Ti6Al4V powder materials on the build quality of laser powder bed fusion–manufactured components.
- Author
-
Hu, Songtao, Zhang, Dongyun, Dong, Dongdong, Liu, Zhiyuan, Huang, Hao, Poprawe, Reinhart, Schleifenbaum, Johannes Henrich, and Ziegler, Stephan
- Subjects
PARTICLE size distribution ,PARTICULATE matter ,LASER beams ,SURFACE roughness ,POWDERS - Abstract
The building quality of the LPBF (laser powder bed fusion)-fabricated component is critical to determine whether it can be applied in the serving condition. However, it is determined not only by process parameters; the powder property and its affecting factors such as average particle sizes and particle size distribution of powder materials have also significant effect on the building quality. In order to investigate the correlation between the building quality and powder properties, five kinds of powder materials with different average particle sizes and particle size distributions of P μ 20 , σ 10 , P μ 35 , σ 10 , P μ 50 , σ 10 , P μ 35 , σ 5 , and P μ 35 , σ 15 are prepared on the basis of the Horsfield filling method. The powder properties such as flowability and apparent density are tested, the build qualities such as dimensional accuracy and surface roughness are measured, and their correlation is analyzed. The results show that the powder material with a narrower particle size distribution benefits flowability. That with medium particle size distribution and average particle size, such as P μ 35 , σ 10 , possesses the highest apparent density and acceptable flowability, and the components manufactured with such powder material have the best surface roughness and dimensional accuracy. Besides, an amount of fine particles is required to optimize component density. The above systematic experiments exhibit the correlation among the particle size distribution and the average particle size, powder properties, and build quality, which is beneficial to preparing the powder materials, improving the irradiation conditions of the laser beam, controlling the LPBF process, and further the building quality of LPBF-fabricated component. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
9. Vagus Nerve Stimulation Prevents Endothelial Necroptosis to Alleviate Blood-Spinal Cord Barrier Disruption After Spinal Cord Injury.
- Author
-
Chen, Hui, Feng, Zhou, Min, Lingxia, Tan, Mingliang, Zhang, Dongyun, Gong, Qiuwen, Liu, Hongliang, and Hou, Jingming
- Abstract
Vagus nerve stimulation (VNS) is a promising neuromodulation technique, which has been demonstrated to promote functional recovery after spinal cord injury (SCI) in our previous study. But the underlying mechanism remains to be explored. Using a compressed SCI model, our present study first demonstrated that activated microglia produce abundant tumor necrosis factor-α (TNF-α) to induce endothelial necroptosis via receptor-interacting protein kinase 1 (RIP1)/RIP3/mixed lineage kinase domain-like protein (MLKL) pathway, thus destroying the blood-spinal cord barrier (BSCB) after SCI. While both TNF-α specifical antibody (infliximab) and necroptosis inhibitor (necrostatin-1) alleviate BSCB disruption. Then our study found that VNS significantly inhibits microglia-derived TNF-α production and reduces expression of p-RIP3 and p-MLKL in endothelial cells. As expected, further results indicated that VNS mitigates the BSCB disruption, thus reducing inflammatory cells infiltration and neural damage. Finally, both electrophysiological evaluation and locomotor test demonstrated that VNS promotes motor function recovery after SCI. In conclusion, our data demonstrated VNS restricts microglia-derived TNF-α to prevent RIP1/RIP3/MLKL mediated endothelial necroptosis, thus alleviating the decisive pathophysiological BSCB disruption to reduce neuroinflammation and neural damage, which ultimately promotes motor function recovery after SCI. Therefore, these results further elaborate that VNS might be a promising therapeutic strategy for SCI. Vagus nerve stimulation prevents microglia-derived TNF-α induced endothelial necroptosis to alleviate blood-spinal cord barrier disruption after spinal cord injury. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
10. Body effect on inflow distortion in civil engine intake under crosswind condition.
- Author
-
Li, Yan, Chen, Yingchun, Cheng, Pan, and Zhang, Dongyun
- Published
- 2023
- Full Text
- View/download PDF
11. Refractory corticotroph adenomas.
- Author
-
Sumal, Amit K. S., Zhang, Dongyun, and Heaney, Anthony P.
- Abstract
The majority of corticotroph adenomas are benign but some are locally invasive, demonstrate high rates of recurrence, and exhibit a relatively poor response to often repeated surgical, medical, and radiation treatment. Herein, we summarize the currently known somatic and genetic mutations and other molecular factors that influence the pathogenesis of these tumors and discuss currently available therapies. Although recent molecular studies have advanced our understanding of the pathogenesis and behavior of these refractory corticotroph adenomas, these insights do not reliably guide treatment choices at present. Development of additional diagnostic tools and novel tumor-directed therapies that offer efficacious treatment choices for patients with refractory corticotroph adenomas are needed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
12. Doped cation radius optimization of Li0.99M0.01Ni0.8Co0.1Mn0.1O2 (M=Ca, Sr, Ba) based on DFT calculation and electrochemical performance of Li-ion battery.
- Author
-
Nian, Song, Xu, Cong, Sun, Guanghan, Yu, Yongquan, Zhang, Dongyun, and Chang, Chengkang
- Subjects
ALKALINE earth metals ,BAND gaps ,LITHIUM-ion batteries ,FERMI energy ,DENSITY functional theory ,LATTICE constants - Abstract
To explore the influence of cation doping with cation radius variation on LiNi
0.8 Co0.1 Mn0.1 O2 , a series of layered Li0.99 M0.01 Ni0.8 Co0.1 Mn0.1 O2 (M-NCM, M=Ca, Sr, Ba) cathode materials were synthesized. Through density functional theory (DFT) calculations, all doped models have low band gaps and more relative electrons near the Fermi energy level than the pristine model. With increasing cation radius, the improvement in electronic conductivity diminishes. X-ray diffraction data and structural refinement results show that lattice parameters and lithium layer increase with increasing doping cation radius. The Ba-NCM sample, which has the largest radius, has the highest initial capacity (246.6 mAh·g−1 ) at 0.1 C. The Ca-NCM sample, with the least doping cation radius, has the highest capacity retention, which reaches to 90.06% after 100 cycles at 1 C. The Sr-NCM sample exhibits the highest remaining capacity, which could retain 146.5 mAh·g−1 at 5 C and 158.7 mAh·g−1 after 100 cycles at 1 C. This is attributed to the highest Li+ diffusion coefficient (8.49 × 10−11 cm2 ·s−1 ) and moderate electronic conductivity and radius of Sr2+ . Doping Li sites in LiNi0.8 Co0.1 Mn0.1 O2 with divalent cations of proper radius could be effectively improved the comprehensive electrochemical performance. This effect is based on not only the pillar effect and high electronic conductivity but also the trade-off between the expansion of lithium layer thickness and introduction of steric hindrance, as a consequence of the cations doping. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
13. Whole Exome Sequencing Identifies PHF14 Mutations in Neurocytoma and Predicts Responsivity to the PDGFR Inhibitor Sunitinib.
- Author
-
Zhang, Dongyun, Yong, William, Movassaghi, Masoud, Rodriguez, Fausto J., Yang, Issac, McKeever, Paul, Qian, Jiang, Li, Jian Yi, Mao, Qinwen, Newell, Kathy L., Green, Richard M., Welsh, Cynthia T., and Heaney, Anthony P.
- Subjects
SUNITINIB ,PLATELET-derived growth factor ,DIABETES insipidus ,SOMATIC mutation ,NEUROBLASTOMA ,EPIDERMAL growth factor receptors ,PLANT mutation ,HOMEOBOX proteins - Abstract
Neurocytomas are rare low-grade brain tumors predominantly affecting young adults, but their cellular origin and molecular pathogenesis is largely unknown. We previously reported a sellar neurocytoma that secreted excess arginine vasopressin causing syndrome of inappropriate anti-diuretic hormone (SIADH). Whole exome sequencing in 21 neurocytoma tumor tissues identified somatic mutations in the plant homeodomain finger protein 14 (PHF14) in 3/21 (14%) tumors. Of these mutations, two were missense mutations and 4 caused splicing site losses, resulting in PHF14 dysfunction. Employing shRNA-mediated knockdown and CRISPR/Cas9-based knockout approaches, we demonstrated that loss of PHF14 increased proliferation and colony formation in five different human, mouse and rat mesenchymal and differentiated cell lines. Additionally, we demonstrated that PHF14 depletion resulted in upregulation of platelet derived growth factor receptor-alpha (PDGFRα) mRNA and protein in neuroblastoma SHSY-5Y cells and led to increased sensitivity to treatment with the PDGFR inhibitor Sunitinib. Furthermore, in a neurocytoma primary culture harboring splicing loss PHF14 mutations, overexpression of wild-type PHF14 and sunitinib treatment inhibited cell proliferation. Nude mice, inoculated with PHF14 knockout SHSY-5Y cells developed earlier and larger tumors than control cell-inoculated mice and Sunitinib administration caused greater tumor suppression in mice harboring PHF-14 knockout than control SHSY-5Y cells. Altogether our studies identified mutations of PHF14 in 14% of neurocytomas, demonstrate it can serve as an alternative pathway for certain cancerous behavior, and suggest a potential role for Sunitinib treatment in some patients with residual/recurrent neurocytoma. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
14. Numerical Simulation in the Melt Pool Evolution of Laser Powder Bed Fusion Process for Ti6Al4V.
- Author
-
Xu, Yixuan, Zhang, Dongyun, Deng, Junyuan, Wu, Xuping, Li, Lingshan, Xie, Yinkai, Poprawe, Reinhart, Schleifenbaum, Johannes Henrich, and Ziegler, Stephan
- Subjects
GAS-liquid interfaces ,FLUID flow ,HEAT conduction ,COMPUTER simulation ,POWDERS ,SURFACE topography - Abstract
In order to track the free interface of the melt pool and understand the evolution of the melt pool, the flow of fluid, and the interface behavior of gas and liquid, a physical model is developed by using the VOF method in this paper. Its characteristics are a combined heat source model, including a parabolic rotation and a cylindrical distribution, and a powder bed stochastic distributed model with powder particle size. The unit interface between the metallic and gas phase in the laser–powder interaction zone can only be loaded by the heat source. Only the first and second laser scanning tracks are simulated to reduce the calculation time. The simulation results show that process parameters such as laser power and scanning speed have significant effects on the fluid flow and surface morphology in the melt pool, which are in good agreement with the experimental results. Compared with the first track, the second track has larger melt pool geometry, higher melt temperature, and faster fluid flow. The melt flows intensely at the initial position due to the high flow rate in the limited melt space. Because there is enough space for the metal flow, the second track can obtain smooth surface morphology more easily compared to the first track. The melt pool temperature at the laser beam center fluctuates during the laser scanning process. This depends on the effects of the interaction between heat conduction or heat accumulation or the interaction between heat accumulation and violent fluid flow. The temperature distribution and fluid flow in the melt pool benefit the analysis and understanding of the evolution mechanism of the melt pool geometry and surface topography and further allow regulation of the L-PBF process of Ti6Al4V. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
15. 18F-FDG and 68 Ga-FAPI PET/CT for the evaluation of periprosthetic joint infection and aseptic loosening in rabbit models.
- Author
-
Wang, Yiqun, Li, Yu, Han, Liang, Wang, Jun, Zhang, Cong, Qi, Erpeng, Zhang, Dongyun, Zhang, Xiaojun, Huan, Yong, and Tian, Jiahe
- Subjects
JOINT infections ,ARTHROPLASTY ,RABBITS ,X-ray computed microtomography ,SCANNING electron microscopy - Abstract
Purpose: We built a joint replacement loosening model based on the original rabbit model of infection and evaluated the performance characteristics of 18F-FDG and 68 Ga-FAPI in evaluating infection and loosening.Methods: After surgery, the rabbits were divided into four groups, with six individuals in the control group and 10 each in the aseptic loosening, S. aureus and S. epidermidis groups. PET/CT and serological examination were performed three times at two-week intervals. After the rabbits were euthanized, micro-CT, tissue pathology, pullout tests and scanning electron microscopy (SEM) were performed.Results: The pullout test and SEM showed the feasibility of the aseptic loosening model. 18F-FDG showed similar performance in the control and loosening groups. The SUVmax of the S. aureus group was consistently higher than that of the S. epidermidis group. As for 68 Ga-FAPI, the SUVmax of the control group was lowest in the second week and gradually increased over subsequent weeks. The SUVmax of the loosening group began to exceed that of the control group after the second week. The SUVmax of the S. aureus group in the second week was the lowest among the four groups and increased as the number of weeks increased. The pathology results showed concordance with the performance of PET/CT. Linear regressions between SUVmax and serology showed that 18F-FDG was positively correlated with CRP and IL-6, while 68 Ga-FAPI revealed negative correlations with CRP and IL-6 in the second week and positive correlations in the sixth week. In addition, the SUVmax and MT(target)V of both 18F-FDG and 68 Ga-FAPI were negatively correlated with bone volume/trabecular volume (TV) and bone surface area/TV.Conclusion: In this longitudinal observation, 68 Ga-FAPI showed greater sensitivity than 18F-FDG in detecting diseases, and 68 Ga-FAPI had no intestinal or muscular uptake. The MT(target)V of 68 Ga-FAPI was larger than that of 18F-FDG, which meant that 68 Ga-FAPI had the potential to define the scope of lesions more accurately. Finally, the SUVmax of 68 Ga-FAPI could not differentiate between loosening and infection; further study of the diagnostic criteria is warranted. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
16. Vagus Nerve Stimulation Reduces Neuroinflammation Through Microglia Polarization Regulation to Improve Functional Recovery After Spinal Cord Injury.
- Author
-
Chen, Hui, Feng, Zhou, Min, Lingxia, Deng, Weiwei, Tan, Mingliang, Hong, Jian, Gong, Qiuwen, Zhang, Dongyun, Liu, Hongliang, and Hou, Jingming
- Subjects
VAGUS nerve stimulation ,SPINAL cord injuries ,VAGUS nerve ,NICOTINIC acetylcholine receptors ,EVOKED potentials (Electrophysiology) ,NEUROINFLAMMATION - Abstract
Background: Spinal cord injury (SCI) is a devastating disease that lacks effective treatment. Interestingly, recent studies indicated that vagus nerve stimulation (VNS), neuromodulation that is widely used in a variety of central nervous system (CNS) diseases, improved motor function recovery after SCI. But the exact underlying mechanism of how VNS ameliorates SCI is unclear. This study aimed to confirm the efficacy and further explore the potential therapeutic mechanism of VNS in SCI. Method: A T10 spinal cord compression model was established in adult female Sprague-Dawley rats. Then the stimulation electrode was placed in the left cervical vagus nerve (forming Sham-VNS, VNS, and VNS-MLA groups). Basso-Beattie-Bresnahan (BBB) behavioral scores and Motor evoked potentials (MEPs) analysis were used to detect motor function. A combination of histological and molecular methods was used to clarify the relevant mechanism. Results: Compared with the Sham-VNS group, the VNS group exhibited better functional recovery, reduced scar formation (both glial and fibrotic scars), tissue damage, and dark neurons, but these beneficial effects of VNS were diminished after alpha 7 nicotinic acetylcholine receptor (α7nAchR) blockade. Specifically, VNS inhibited the pro-inflammatory factors TNF-α, IL-1β, and IL-6 and increased the expression of the anti-inflammatory factors IL-10. Furthermore, we found that VNS promotes the shift of M1-polarized Iba-1
+ /CD86+ microglia to M2-polarized Iba-1+ /CD206+ microglia via upregulating α7nAchR to alleviate neuroinflammation after SCI. Conclusion: Our results demonstrated that VNS promotes microglial M2 polarization through upregulating α7nAChR to reduce neuroinflammation, thus improving motor function recovery after SCI. These findings indicate VNS might be a promising neuromodulation strategy for SCI. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
17. Teacher mindset change in boundary-crossing lesson study:a case from China.
- Author
-
Chen, Xiangming, Ou, Qunhui, An, Chao, and Zhang, Dongyun
- Published
- 2022
- Full Text
- View/download PDF
18. TNF-α Antagonizes the Effect of Leptin on Insulin Secretion through FOXO1-Dependent Transcriptional Suppression of LepRb in INS-1 Cells.
- Author
-
Zhang, Yang, Jin, Weidong, Zhang, Dongyun, Lin, Changhai, He, Haiyan, Xie, Fengxin, Gan, Lixia, Fu, Weiling, Wu, Lixiang, and Wu, Yongzhong
- Published
- 2022
- Full Text
- View/download PDF
19. Remifentanil protects heart from myocardial ischaemia/reperfusion (I/R) injury via miR-206-3p/TLR4/NF-κB signalling axis.
- Author
-
Zhang, Dongyun, Wang, Qun, Qiu, Xunbin, Chen, Yiguan, Yang, Xiaoli, and Guan, Yujian
- Subjects
MYOCARDIAL ischemia ,REMIFENTANIL ,REPERFUSION ,HEMATOXYLIN & eosin staining ,MYOCARDIAL infarction ,WOUNDS & injuries - Abstract
Objectives: Myocardial I/R injury is one of the most serious complications after reperfusion therapy in patients with myocardial infarction. Remifentanil has been found to protect the heart against I/R injury. However, its underlying mechanism remains uncertain in myocardial I/R injury. Methods: The myocardial I/R injury rat model was established by 30 min of ischaemia followed by 24 h of reperfusion. The animal model was evaluated by the levels of TC, ALT and AST and H&E staining. The binding of miR-206-3p and TLR4 was predicted and verified using TargetScan software, luciferase reporter and RNA pull-down assays. The functional role and mechanism of remifentanil were identified by ultrasonic echocardiography, oxidative stress markers, H&E, Masson and TUNEL staining and western blot. Key findings: The rat myocardial I/R injury model displayed a significantly high level of TC, ALT, AST, TLR4, p-IκBα and p-p65 and the presence of disorganized cells and inflammatory cell infiltration. The model also showed increased levels of LVEDD, LVESD, MDA, fibrosis and apoptosis and decreased levels of EF, FS, SOD and GSH, which were reversed with remifentanil treatment. Knockdown of miR-206-3p damaged cardiac function and aggravated oxidative stress. miR-206-3p could directly bind to TLR4. TLR4 overexpression destroyed cardiac function, exacerbated oxidative stress, increased levels of p-IκBα and p-p65 and aggravated pathology manifestation affected by remifentanil. Conclusions: Our results elucidated that remifentanil alleviated myocardial I/R injury by miR-206-3p/TLR4/NF-κB signalling axis. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. Selection of Cashmere Fineness Functional Genes by Translatomics.
- Author
-
Zhang, Yu, Zhang, Dongyun, Xu, Yanan, Qin, Yuting, Gu, Ming, Cai, Weidong, Bai, Zhixian, Zhang, Xinjiang, Chen, Rui, Sun, Yingang, Wu, Yanzhi, and Wang, Zeying
- Subjects
CASHMERE ,GENOME-wide association studies ,GENES ,NUCLEOTIDE sequencing - Abstract
Cashmere fineness is an important index to evaluate cashmere quality. Liaoning Cashmere Goat (LCG) has a large cashmere production and long cashmere fiber, but its fineness is not ideal. Therefore, it is important to find genes involved in cashmere fineness that can be used in future endeavors aiming to improve this phenotype. With the continuous advancement of research, the regulation of cashmere fineness has made new developments through high-throughput sequencing and genome-wide association analysis. It has been found that translatomics can identify genes associated with phenotypic traits. Through translatomic analysis, the skin tissue of LCG sample groups differing in cashmere fineness was sequenced by Ribo-seq. With these data, we identified 529 differentially expressed genes between the sample groups among the 27197 expressed genes. From these, 343 genes were upregulated in the fine LCG group in relation to the coarse LCG group, and 186 were downregulated in the same relationship. Through GO enrichment analysis and KEGG enrichment analysis of differential genes, the biological functions and pathways of differential genes can be found. In the GO enrichment analysis, 491 genes were significantly enriched, and the functional region was mainly in the extracellular region. In the KEGG enrichment analysis, the enrichment of the human papillomavirus infection pathway was seen the most. We found that the COL6A5 gene may affect cashmere fineness. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
21. Selection of Cashmere Fineness Functional Genes by Translatomics.
- Author
-
Zhang, Yu, Zhang, Dongyun, Xu, Yanan, Qin, Yuting, Gu, Ming, Cai, Weidong, Bai, Zhixian, Zhang, Xinjiang, Chen, Rui, Sun, Yingang, Wu, Yanzhi, and Wang, Zeying
- Subjects
CASHMERE ,GENOME-wide association studies ,GENES ,NUCLEOTIDE sequencing - Abstract
Cashmere fineness is an important index to evaluate cashmere quality. Liaoning Cashmere Goat (LCG) has a large cashmere production and long cashmere fiber, but its fineness is not ideal. Therefore, it is important to find genes involved in cashmere fineness that can be used in future endeavors aiming to improve this phenotype. With the continuous advancement of research, the regulation of cashmere fineness has made new developments through high-throughput sequencing and genome-wide association analysis. It has been found that translatomics can identify genes associated with phenotypic traits. Through translatomic analysis, the skin tissue of LCG sample groups differing in cashmere fineness was sequenced by Ribo-seq. With these data, we identified 529 differentially expressed genes between the sample groups among the 27197 expressed genes. From these, 343 genes were upregulated in the fine LCG group in relation to the coarse LCG group, and 186 were downregulated in the same relationship. Through GO enrichment analysis and KEGG enrichment analysis of differential genes, the biological functions and pathways of differential genes can be found. In the GO enrichment analysis, 491 genes were significantly enriched, and the functional region was mainly in the extracellular region. In the KEGG enrichment analysis, the enrichment of the human papillomavirus infection pathway was seen the most. We found that the COL6A5 gene may affect cashmere fineness. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
22. Effect of 3 NR3C1 Mutations in the Pathogenesis of Pituitary ACTH Adenoma.
- Author
-
Miao, Hui, Liu, Yang, Lu, Lin, Gong, Fengying, Wang, Linjie, Duan, Lian, Yao, Yong, Wang, Renzhi, Chen, Shi, Mao, Xinxin, Zhang, Dongyun, Heaney, Anthony P, and Zhu, Huijuan
- Subjects
GLUCOCORTICOID receptors ,CUSHING'S syndrome treatment ,ADRENOCORTICOTROPIC hormone - Abstract
Context Glucocorticoids act through the glucocorticoid receptor (GR) encoded by the nuclear receptor subfamily 3 group C member 1 (NR3C1) gene. Objective This study aimed to examine the function of NR3C1 variants and their possible pathogenic role in Cushing disease (CD). Methods Next-generation sequencing was conducted in 49 CD patients. Corticotroph tumor GR protein expression was examined by immunohistochemistry (IHC). Constructs harboring the 3 NR3C1 -mutant and wild-type (WT) GR were transfected into the murine corticotropic adenoma cell line (AtT-20), and GR protein expression was quantified by Western blot. Translocation activity was assessed by immunofluorescence and effects of the GR mutants on corticotroph tumor proliferation, pro-opiomelanocortin (POMC) transcription, and ACTH secretion were tested. Results Clinical features were similar in patients harboring the NR3C1 mutations and WT GR. Recurrent adenomas showed higher GR IHC scores than nonrecurrent tumors. In vitro studies demonstrated that the p.R469X mutant generated a truncated GR protein, and the p.D590G and p.Y693D GR mutants resulted in lower GR expression. Dexamethasone (DEX) treatment of AtT-20 cells demonstrated decreased DEX-induced nuclear translocation, increased cell proliferation, and attenuated suppression of POMC transcription of 3 GR mutants. Interestingly, the p.R469X GR mutant resulted in increased murine corticotroph tumor ACTH secretion compared to WT GR. Conclusion Our findings identify 3/49 (6.1%) consecutive human corticotroph tumors harboring GR mutations. Further findings demonstrate the role NR3C1 plays in CD pathogenesis and offer insights into a novel treatment approach in this patient subset. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. Cr‐doped LiCoMnO4 cathode with high phase purity and promoted electrochemical performance.
- Author
-
Liu, Sanchao, He, Huihui, Zhang, Dongyun, and Chang, Chengkang
- Subjects
CHEMICAL stability ,HIGH voltages ,RIETVELD refinement ,DIFFUSION coefficients ,SPINEL ,CATHODES - Abstract
Summary: To improve the electrochemical performances of high voltage LiCoMnO4 spinel cathode material at 5.3 V, Cr doped LiCoMn1‐xCrxO4 (x = 0, 0.025, 0.050, 0.075) materials were synthesized by a one‐step solid‐state at 750°C. Rietveld refinement results showed that the phase purity of spinel is promoted with the increase in Cr concentration, which can be explained by the strong CrO bond that reduces oxygen deficiency and eliminates Li2MnO3 impurity phase during the synthesis process. Such change in phase purity further causes the improvement in specific capacity, and the 5.0%Cr doped sample displays the best result with a value of 123.0 mAh/g at 0.1°C and 93.3 mAh/g at 10°C. For a comparison, the pristine sample only releases a capacity of 112.6 mAh/g at 0.1°C and 54.8 mAh/g at 10°C. Improved capacity retention, from 83.1% to 90.1% after 100 cycles at 1°C, is also observed due to the suppressed volume change during the redox process after the incorporation of Cr cations in the lattice. Promoted rate performance, attributed from the improved Li ion diffusion coefficient, is also confirmed in the experiment. The improvement of those electrochemical properties could be explained by high‐phase purity and superior structural stability benefited from Cr‐doping. Novelty statement: LiCoMn1‐xCrxO4 (x = 0, 0.025, 0.050, 0.075) materials were synthesized by a one‐step solid‐state at 750°C, Chromium had been confirmed to reduce oxygen loss during LiCoMnO4 synthesis due to high oxygen affinity of Cr, which improves phase purity. As a result, the specific capacity was increased. Cr‐doping enhances the structural stability so that capacity retention was promoted due to higher bond energy of CrO than MnO; rate performance was also enhanced due to the improved diffusion coefficient. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
24. EFL Lecturers' Metadiscourse in Chinese University MOOCs Across Course Types.
- Author
-
Zhang, Dongyun and Sheng, Diyun
- Published
- 2021
- Full Text
- View/download PDF
25. Microstructure and mechanical properties of double-sided welded joints in MX246A high-temperature alloy.
- Author
-
Li, Jianmin, Zhang, Dongyun, Geng, Shuo, Chi, Yujing, and Yi, Denghao
- Published
- 2023
- Full Text
- View/download PDF
26. Feasible synthesis of NCM811 cathodes with controllable Li/Ni cationic mixing for enhanced electrochemical performance via a nano grinding assisted solid‐state approach.
- Author
-
He, Huihui, Dong, Jian, Zhang, Dongyun, Hang, Daojin, Zhu, Xiaojing, and Chang, Chengkang
- Subjects
ELECTROCHEMICAL electrodes ,CATHODES ,INTERFACIAL resistance ,RAW materials ,MASS production - Abstract
Summary: This paper reports a feasible approach to offer LiNi0.8Co0.1Mn0.1O2 (NCM811) layered cathode materials with enhanced lattice ordering and improved electrochemical performance through a nano grinding assisted solid‐state reaction. Different from the commercial precursor method, oxide raw materials, NiO, CoO and MnO2, rather than the hydroxides, was employed as the starting raw material which was milled into submicron size, pressed into pellets and crushed into granular powder. After calcination under oxygen atmosphere under different temperature, such a simple approach provides layered cathode materials with controllable Li/Ni disordering. Powder XRD results show that when sintered at 800°C, a largest I(003)/I (104) ratio is observed, indicating that the cationic disordering is the lowest, as been confirmed by the XRD refinement data, showing that only 1.08% Ni is misplaced at 3b site. For the electrochemical test, the pNCM800 sample presented an initial specific discharge capacity of 203 mAh/g at 0.1C, together with a capacity retention of 91.77% after 100 cycles at 0.5C. Compared to the value of the sample obtained at normal routine (163.8 mAh/g and 74.85%), the improvement in electrochemical behavior is obvious. Furthermore, the rate performance is also improved, with a specific capacity of 144.1 mAh/g even at 5C rate. The reason for such enhancement could be ascribed to the better kinetic process with low interfacial resistance and fast Li diffusion contributed from the promoted lattice ordering. The results obtained in the experiments greatly indicate the significance of the approach in controlling the Li/Ni disordering, and thus offer an alternative routine for the mass production of layered cathode materials besides the so‐called precursor method. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
27. Targeting Corticotroph HDAC and PI3-Kinase in Cushing Disease.
- Author
-
Zhang, Dongyun, Damoiseaux, Robert, Babayan, Lilit, Rivera-Meza, Everett Kanediel, Yang, Yingying, Bergsneider, Marvin, Wang, Marilene B, Yong, William H, Kelly, Kathleen, and Heaney, Anthony P
- Subjects
ADRENOCORTICOTROPIC hormone ,TUMOR growth ,CELL survival ,KINASE inhibitors ,SECRETION ,CELL proliferation ,THERAPEUTIC use of antineoplastic agents ,CANCER cell culture ,HIGH throughput screening (Drug development) ,RESEARCH ,PITUITARY diseases ,CUSHING'S syndrome ,HETEROCYCLIC compounds ,ANIMAL experimentation ,RESEARCH methodology ,ADENOMA ,ANTINEOPLASTIC agents ,CELL physiology ,MEDICAL cooperation ,EVALUATION research ,COMPARATIVE studies ,DRUG therapy ,GENES ,MICE ,ENZYME inhibitors ,PHARMACODYNAMICS - Abstract
Context: Cushing disease (CD) is a life-threatening disorder. Therapeutic goals include symptom relief, biochemical control, and tumor growth inhibition. Current medical therapies for CD by and large exert no action on tumor growth.Objective: To identify drugs that inhibit corticotroph tumor adrenocorticotropic hormone (ACTH) secretion and growth.Design: High throughput screen employing a novel "gain of signal" ACTH AlphaLISA assay.Setting: Academic medical center.Patients: Corticotroph tumor tissues from patients with CD.Interventions: None.Main Outcome Measures: Potent inhibitors of corticotroph tumor ACTH secretion and growth.Results: From a kinase inhibitor library, we identified the dual PI3K/HDAC inhibitor CUDC-907 as a potent inhibitor of murine and human corticotroph tumor ACTH secretion (median effective concentration 1-5 nM), and cell proliferation (median inhibitory concentration 5 nM). In an in vivo murine corticotroph tumor xenograft model, orally administered CUDC-907 (300 mg/kg) reduced corticotroph tumor volume (TV [cm3], control 0.17 ± 0.05 vs CUDC-907 0.07 ± 0.02, P < .05) by 65% and suppressed plasma ACTH (ACTH [pg/mL] control 206 ± 27 vs CUDC-907 47 ± 7, P < .05) and corticosterone (corticosterone [ng/mL] control 180 ± 87 vs CUDC-907 27 ± 5, P < .05) levels by 77% and 85% respectively compared with controls. We also demonstrated that CUDC-907 acts through HDAC1/2 inhibition at the proopiomelanocortin transcriptional level combined with its PI3K-mediated inhibition of corticotroph cell viability to reduce ACTH secretion.Conclusions: Given its potent efficacy in in vitro and in vivo models of CD, combined with proven safety and tolerance in clinical trials, we propose CUDC-907 may be a promising therapy for CD. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
28. High rate and cyclic performance of Na3–2xMgxV2(PO4)3/C cathode for sodium-ion batteries.
- Author
-
Wang, Mengmeng, Tao, Yueming, Zhang, Dongyun, Sun, Guanghan, Feng, Ping, and Chang, Chengkang
- Subjects
SODIUM ions ,X-ray photoelectron spectroscopy ,ELECTRIC batteries ,RIETVELD refinement ,UNIT cell ,CATHODES ,ELECTROCHEMICAL electrodes - Abstract
Na
3–2x Mgx V2 (PO4 )3 /C (0 ≤ x ≤ 0.2) were synthesized by a sol–gel method. According to X-ray diffraction (XRD) Rietveld refinement and energy dispersive spectroscopy (EDS) mapping results, Mg ions were approved to occupy the Na2 (18e) site in Na3–2x Mgx V2 (PO4 )3 /C for the first time. The amount of Mg substitution in Na3–2x Mgx V2 (PO4 )3 /C was optimized. The specific discharge capacities of Na2.9 Mg0.05 V2 (PO4 )3 /C at 10 C, 20 C, and 30 C were 98.9%, 91.5%, and 76.2% of the value obtained at 1 C, respectively. Na2.9 Mg0.05 V2 (PO4 )3 /C exhibited the highest capacity retention of 80.3% with a discharge capacity of 77.3 mAh·g−1 after 1200 cycles at 10 C. Na2.9 Mg0.05 V2 (PO4 )3 /C exhibited superior rate performance, resulting from a high sodium diffusion coefficient (DNa ) of 3.91 × 10–12 cm2 ·s−1 and the excellent electrical conductivity (5.7 × 10–2 s·cm−1 ). Combining the X-ray photoelectron spectroscopy (XPS) and Electrochemical impedance spectroscopy (EIS) results, the mechanism of Mg substitution was investigated. Since two Na+ were replaced by one Mg2+ , V Na ′ was produced to maintain valence equilibrium. This phenomenon benefited Na+ migration by broadening the diffusion channel in the structure of Na3 V2 (PO4 )3 . According to the EPR results, the signal intensity of Na2.9 Mg0.05 V2 (PO4 )3 /C was much stronger than that of Na3 V2 (PO4 )2 /C, thus confirming the existence of V Na ′ after Mg substitution. When the amount of Mg substitution was further increased to 0.1, the DNa decreased because of the small radius of Mg2+ , which led to severe lattice distortion and volumetric shrinkage of the unit cell. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
29. New composite Li1.4Mn0.61Ni0.18Co0.18Al0.03O2.4 and LiNi0.5Mn1.5O3.9F0.1 cathode material with higher specific capacity and better capacity retention.
- Author
-
Zhu, Hui, Xiao, Yingjun, Dong, Jian, Zhang, Dongyun, and Chang, Chengkang
- Abstract
Aluminum-modified Li
1.4 Mn0.61 Ni0.18 Co0.18 Al0.03 O2.4 (LNCMA) and fluorine-modified LiNi0.5 Mn1.5 O3.9 F0.1 (LNMOF) cathode materials were successfully synthesized via a solid-state reaction procedure. The discharge capacity of the LNCMA increased from 175.3 to 192.2 mAh g−1 , showing approximately a 9.6% improvement after 50 cycles due to Al doping. For the LNMOF cathode, the discharge capacity increased from 116.9 to 174.9 mAh g−1 after F doping, corresponding to an increase of 49.6% after 50 cycles. The new composite cathode was formed by mixing the two cathode materials at a weight ratio of 1:1, which was selected based on the charge–discharge profiles during the first cycle. When the cells were tested in a voltage range of 2.0–4.85 V, the composite material exhibited initial specific capacities of 229.2 and 215.4 mAh g−1 , a coulombic efficiency of 94.0% during the first cycle, and a capacity retention of 94.5% after 50 cycles at 0.2C. The concept of inserting irreversible Li ions from the Li-rich material into the 16c vacancy of the LNMOF was validated. The improved capacity was due to the plateau in the discharge capacity curves due to the Mn3+ → Mn2+ reduction. The charge–discharge capacities of the composite material were higher than those in the literature, as was the coulombic efficiency. The new composite material inherited a high-voltage plateau from the LNMOF and a high specific capacity from the LNCMA, and this material has great potential for future applications. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
30. Chemotherapeutic Nanoparticle-Based Liposomes Enhance the Efficiency of Mild Microwave Ablation in Hepatocellular Carcinoma Therapy.
- Author
-
Wu, Songsong, Zhang, Dongyun, Yu, Jie, Dou, Jianping, Li, Xin, Mu, Mengjuan, and Liang, Ping
- Subjects
HEPATOCELLULAR carcinoma ,LIVER cancer ,MICROWAVES ,CELL death ,CAUSES of death ,LIPOSOMES - Abstract
Hepatocellular carcinoma (HCC) is the third leading cause of death from cancer, and the 5-year overall survival (OS) rate for HCC remains unsatisfying worldwide. Microwave ablation (MWA) is a minimally invasive therapy that has made progress in treating HCC. However, HCC recurrence remains problematic. Therefore, combination therapy may offer better outcomes and enhance MWA efficiency through improved tumor control. We have developed doxorubicin-loaded liposomes (DNPs) as an efficient nanoplatform to enhance MWA of hepatocellular carcinoma even at the mild ablation condition. In this study, we demonstrated that the uptake of DNPs by HCC cells was increased 1.5-fold compared with that of free DOX. Enhanced synergism was observed in the combination of DNPs and MWA, which induced nearly 80% cell death. The combination of mild MWA and DNPs enhanced the ablation efficiency of HCC with significant inhibition of liver tumors and accounted for the longest survival rate among all groups. A much higher accumulation of the DNPs was observed in the transitional zone than in the ablation zone. No apparent systemic toxicity was observed for any of the treatments after 14 days. The present work demonstrates that DNPs combined with MWA could be a promising nanoparticle-based therapeutic approach for the treatment of hepatocellular carcinoma and shows potential for future clinical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
31. Downregulation of miR-200c stabilizes XIAP mRNA and contributes to invasion and lung metastasis of bladder cancer.
- Author
-
Jin, Honglei, Xue, Lei, Mo, Lan, Zhang, Dongyun, Guo, Xirui, Xu, Jiheng, Li, Jingxia, Peng, Minggang, Zhao, Xuewei, Zhong, Minghao, Xu, Dazhong, Wu, Xue-Ru, Huang, Haishan, and Huang, Chuanshu
- Published
- 2019
- Full Text
- View/download PDF
32. The prognostic values of estrogen receptor alpha and beta in patients with gastroesophageal cancer: A meta-analysis.
- Author
-
Dongyun Zhang, Jianwei Ku, Yingjie Yi, Junhui Zhang, Rongzhi Liu, Nianya Tang, Zhang, Dongyun, Ku, Jianwei, Yi, Yingjie, Zhang, Junhui, Liu, Rongzhi, and Tang, Nianya
- Published
- 2019
- Full Text
- View/download PDF
33. Residual Tumor Confers a 10-Fold Increased Risk of Regrowth in Clinically Nonfunctioning Pituitary Tumors.
- Author
-
Maletkovic, Jelena, Dabbagh, Asmaa, Zhang, Dongyun, Zahid, Abdul, Bergsneider, Marvin, Wang, Marilene B, Linetsky, Michael, Salamon, Noriko, Yong, William H, Vinters, Harry V, and Heaney, Anthony P
- Subjects
PITUITARY tumors ,PITUITARY surgery ,TUMOR growth - Abstract
Objective We evaluated tumor recurrence and regrowth rates following endoscopic transnasal transsphenoidal (TNTS) surgical removal in a consecutive series of clinically nonfunctioning pituitary adenomas (CNFTs). Design Retrospective chart review of clinical, biochemical, and sellar MRI findings in all TNTS surgeries in patients with CNFT, performed by a single surgeon, between 2008 and 2015 (n = 280). Patients Ninety-three patients met eligibility criteria, with complete clinical, biochemical, and imaging follow-up for a 3-year minimum. Results Of 85 patients who were not irradiated, 3-month postsurgical MRI demonstrated no residual tumor in 58 of 85 (68.2%), equivocal findings in 12 of 85 (14.1%), and definite residual tumor in 15 of 85 (17.6%) patients. Six of 85 (7.1%) demonstrated tumor regrowth by 3 years, and 2 further patients demonstrated true tumor recurrence at 3 and 6 years after surgery, respectively, for a total recurrence rate of 9.4% (8 of 85). Eight of the 93 patients were irradiated between 3 months and 4 years after pituitary surgery. In 3 patients with tumor regrowth, 2 exhibited residual tumor and 1 had no residual findings at the 3-month postoperative imaging. Overall, Ki-67 labeling index or Knosp grading did not predict recurrence. Conclusion Tumor recurrence at 3 years was low (1 of 58; 1.7%) if the 3-month postoperative MRI showed no residual tumor. The findings support a less frequent imaging schedule for this group. Patients with definite residual tumor visible at 3 months harbor the greatest risk for tumor growth, but regrowth does not occur in all patients (6 of 15; 40%). [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
34. Boron improved electrochemical performance of LiNi0.8Co0.1Mn0.1O2 by enhancing the crystal growth with increased lattice ordering.
- Author
-
Dong, Jian, He, HuiHui, Zhang, Dongyun, and Chang, Chengkang
- Subjects
CRYSTAL growth ,ELECTROCHEMICAL electrodes ,LAYER structure (Solids) ,LIQUID phase epitaxy ,INTERFACIAL resistance ,BORON ,CRYSTAL lattices - Abstract
Boron-modified Li(Ni
0.8 Co0.1 Mn0.1 )1−x Bx O2 cathode materials(NCM811) were successfully prepared by a nano-milling assisted solid-state approach. X-ray diffraction investigations showed that the materials are solid solutions with a layered structure. SEM observations implied that the doped B ions promoted the growth of the target crystal with well-developed facets since it will form liquid phase at lower temperature. The intensity ratio of I(003)/I(104) raised with the increase in Boron doping concentration, until a maximum value of 1.453 was observed at x = 0.01. Further Rietveld refinements revealed that boron ions occupy the crystal lattice in the transition metal slab which helps to promote the lattice ordering by decreasing the Li/Ni ionic mixing. Such B promoted NCM811 cathode materials were confirmed to have an improved diffusion coefficient with a reduced interfacial resistance by subsequent CV and EIS measurements. From the electrochemical test, those B modified NCM811 cathode materials presented enhanced electrochemical performance. Among the synthesized samples, Li(Ni0.8 Co0.1 Mn0.1 )0.99 B0.01 O2 exhibited the best specific capacity, with 194.7 mAh g−1 and 166.8 mAh g−1 at 0.1C and 5C respectively. The capacity retention at 0.5C was also confirmed as 98.2% after 100 cycles. Such improvement can be explained by the reduced Li/Ni ionic mixing, the increased Li ionic diffusion and the reduced interfacial resistance caused by the promoted growth of the B doped NCM811 crystals. Compared to those NCM811 materials reported elsewhere, the material obtained by this approach showed high potential for future application. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
35. Cost effective and eco-friendly synthesis of LiFePO4/C cathode material from a natural mineral magnetite.
- Author
-
Dong, Jian, He, HuiHui, He, Qiao, Zhang, Dongyun, and Chang, Chengkang
- Subjects
MAGNETITE ,CATHODES ,IRON composites ,MASS production ,ENVIRONMENTAL economics ,SURFACE diffusion ,MATERIALS - Abstract
A cost effective and eco-friendly approach for the preparation of LiFePO
4 /C cathode material is proposed in this paper. High-purity natural mineral magnetite (Fe3 O4 ≥ 99%) was employed as the only ferric source in the synthesis routine. By ultrafine ball milling and subsequent oxidation, the magnetite was converted into FePO4 ·2H2 O. After dehydration, the iron phosphate reacted with Li2 CO3 and sucrose to form the target LiFePO4 /C composite. Mössbauer result revealed that all the Fe cations exhibited + 2 valence state in the LiFePO4 lattice although redox process of the species occurred during the synthesis. SEM observations indicated that the pure phase LiFePO4 powders with round shape were constructed by fine primary grains with size of 100–200 nm. Such micro-nano structure offered an increased Li diffusion by increasing the surface area and reducing the migration pathway. LiFePO4 /C composite synthesized by this magnetite approach exhibited excellent performance with a specific capacity of 161.1 mAh g−1 at 0.1 C and a capacity retention rate of 98.8% after 100 cycles at 1 C. The new approach we proposed presents the remarkable advantages of low cost and environmental friendliness, and therefore suggest significant potential in mass production. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
36. Autophagy-mediated Mir6981 degradation exhibits CDKN1B promotion of PHLPP1 protein translation.
- Author
-
Peng, Minggang, Wang, Jingjing, Tian, Zhongxian, Zhang, Dongyun, Jin, Honglei, Liu, Claire, Xu, Jiawei, Li, Jingxia, Hua, Xiaohui, Xu, Jiheng, Huang, Chao, and Huang, Chuanshu
- Abstract
PHLPP1 (PH domain and leucine rich repeat protein phosphatase 1) is a newly identified family of Ser/Thr phosphatases that catalyzes the dephosphorylation of a conserved regulatory motif of the AGC kinases resulting in a tumor suppressive function, while CDKN1B/p27 also acts as a tumor suppressor by regulating cell cycle, senescence, apoptosis, and cell motility. Our most recent studies reveal that CDKN1B is required for PHLPP1 abundance, which contributes to the inhibition of carcinogenic arsenite-induced cell malignant transformation through inhibition of RPS6-mediated Hif1a translation. However, nothing is known about the mechanisms underlying the crosstalk between these 2 key tumor suppressors in intact cells. Here, for the first time to the best of our knowledge, we show that CDKN1B is able to promote PHLPP1 protein translation by attenuating the abundance of Mir6981, which binds directly to the 5ʹuntranslated region (UTR) of Phlpp1 mRNA. Further studies indicate that the attenuation of Mir6981 expression is due to macroautophagy/autophagy-mediated degradation of Mir6981 in an SQSTM1/p62-dependent fashion. Moreover, we have determined that Sqstm1 is upregulated by CDKN1B at the level of transcription via enhancing SP1 protein stability in an HSP90-depdendent manner. Collectively, our studies prove that: 1) SQSTM1 is a CDKN1B downstream effector responsible for CDKN1B-mediated autophagy; 2) by promoting the autophagy-mediated degradation of Mir6981, CDKN1B exerts a positive regulatory effect on PHLPP1 translation; 3) Mir6981 suppresses PHLPP1 translation by binding directly to its mRNA 5ʹ-UTR, rather than classical binding to the 3ʹ-UTR. These findings provide significant insight into understanding the crosstalk between CDKN1B and PHLPP1. Abbreviations: ATG: autophagy related; ACTB: actin beta; BAF: bafilomycin; BECN1: beclin 1; Cdkn1b/p27: cyclin-dependent kinase inhibitor 1B; CHX: cycloheximide; DMEM: dulbecco's modified eagle medium; FBS: fetal bovine serum; GAPDH: glyceraldehyde −3-phosphate dehydrogenase; Hif1a: hypoxia inducible factor 1, alpha subunit; Hsp90: heat shock protein 90; JUN: Jun proto-oncogene, AP1 transcription factor subunit; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MG132: proteasome inhibitor; Mtor: mechanistic target of rapamycin kinase; Phlpp1: PH domain and leucine rich repeat protein phosphatase 1; Phlpp2: PH domain and leucine rich repeat protein phosphatase 2; Pp2c: protein phosphatase 2 C; RPS6: ribosomal protein S6; Sp1: trans-acting transcription factor 1; Sqstm1/p62: sequestosome 1; TUBA: alpha tubulin; 3ʹ-UTR; 3ʹ-untranslated region; 5ʹ-UTR: 5ʹ-untranslated region. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
37. Theranostic liposomes as nanodelivered chemotherapeutics enhanced the microwave ablation of hepatocellular carcinoma.
- Author
-
Zhou, Qunfang, Wang, Kun, Dou, Jianping, Cao, Feng, Liu, Fengyong, Yuan, Hongjun, Mu, Mengjuan, Xu, Jinshun, Zhang, Dongyun, Li, Xin, Tian, Jie, Yu, Jie, and Liang, Ping
- Abstract
Aim: This study aimed to develop indocyanine green- and doxorubicin-loaded liposomes (DILPs) as theranostic nanoplatform for the detection of hepatocellular carcinoma (HCC) and as an efficient chemotherapeutic to enhance microwave ablation. Materials & methods: DILPs were synthesized and thoroughly characterized. Biocompatibility, tumor uptake and accumulation, and synergistic ablation-chemotherapeutic efficiency were systematically explored in them. In addition, human HCC surgical samples were used to test the affinity of DILPs for HCC. Results: The combination of microwave ablation and DILPs enhanced the ablation efficiency of HCC with apparent tumor inhibition. DILPs exhibited excellent diagnostic ability and could detect 2.5-mm HCC lesions via optoacoustic tomography imaging. DILPs had better affinity for human HCC surgical samples compared with normal liver tissue. Conclusion: Theranostic DILPs could serve as promising nanoparticles for treatment and management of HCC in the clinic. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
38. Photoluminescence and afterglow behavior of Ce3+ activated Li2Sr0.9Mg0.1SiO4 phosphor.
- Author
-
Xiao, Yingjun, Zhang, Dongyun, and Chang, Chengkang
- Published
- 2019
- Full Text
- View/download PDF
39. Improved electrochemical performance of P2-type Na0.67Lix(Mn0.5Fe0.25Co0.25)1−xO2 cathode materials from Li ion substitution of the transition metal ions.
- Author
-
Lv, Tingjian, Guan, Li, Xiao, Peng, Zhang, Dongyun, and Chang, Chengkang
- Subjects
CATHODES ,LITHIUM ions ,TRANSITION metals ,PHASE transitions ,ELECTRONIC materials - Abstract
In this work, we report the preparation and the enhanced electrochemical performance of P2-type Na
0.67 Lix (Mn0.5 Fe0.25 Co0.25 )1−x O2 layered cathode materials with different Li substitutions via a nanomilling-assisted solid-state method. The experimental results show that the introduced lithium ions can greatly improve the performance of the material after entering the transition metal layer. Among these synthesized samples, the Na0.67 Li0.03 (Mn0.5 Fe0.25 Co0.25 )0.97 O2 electrode exhibits an exceptionally high specific capacity of 190.6 mAh g−1 at 0.1 C rate and a capacity retention of 89.5% after 30 cycles. Obviously, the specific capacity retention is improved by 15.3% compared with the pristine Na0.67 (Mn0.5 Fe0.25 Co0.25 )O2 without Li incorporation (the specific capacity retention is only 74.2% after 30 cycles). Simultaneously, the sample also shows a large increase in rate performance compared to the pristine material. All of the enhancement can be explained by the fact that the introduced Li ions suppress the phase transition during the charge-discharge process and avoid the volume expansion of the electrode, which significantly reduce the occurrence of micro-cracks within the electrode. The reduced polarization, the decreased internal resistance of the prepared electrodes and the increased sodium ion diffusion coefficient, as confirmed from the CV and EIS measurements, can be regarded as the three major reasons for the enhanced electrochemical performance of the Li ion-substituted materials. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
40. Enhanced rate performance and cycle stability of LiNi0.8Co0.15Al0.05O2 via Rb doping.
- Author
-
Dong, Jian, Xiao, Peng, Zhang, Dongyun, and Chang, Chengkang
- Subjects
SOLID state chemistry ,TRANSITION metals ,DIFFUSION ,ELECTROCHEMICAL analysis ,LITHIUM ions - Abstract
Rubidium modified Ni-rich LiNi
0.8 Co0.15 Al0.05 O2 cathode materials were successfully synthesized through a nano-milling assisted solid-state method. Rietveld refinement revealed that the Rb ions were incorporated into the lattice by replacing the original Li ions. It resulted in the enlarging of Li layer spacing together with the reducing of the thickness of the transition metal slab. Such changes in crystal structure led to the increase in the diffusion coefficient of Li ions in the lattice (DLi ). Calculated diffusion coefficient presented the highest Li-ion diffusion coefficient of 1.54 × 10−10 cm2 s−1 for the sample Rb0.01 Li0.99 Ni0.8 Co0.15 Al0.05 O2 . It was also in good accordance with the changes in Li slab thickness. Improved electrochemical performance in specific capacity, capacity retention and rate performance were observed. Among the samples synthesized, the Rb0.01 Li0.99 Ni0.8 Co0.15 Al0.05 O2 sample exhibited the highest initial discharge capacity and the best rate performance. It delivered specific discharge capacities of 190.5, 177, 169, 161 and 151 mAh g−1 at 0.1C, 0.2C, 0.5C, 1C and 5C, respectively. It also showed the best cycle stability with capacity retention of 91.31% after 100 cycles at 2C. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
41. Properties of Cmc21-X2As2O (X = Si, Ge, and Sn) by First-Principles Calculations.
- Author
-
Yang, Ruike, Ma, Yucan, Wei, Qun, and Zhang, Dongyun
- Subjects
PHONON dispersion relations ,DENSITY functional theory ,ELASTIC constants ,YOUNG'S modulus ,ANISOTROPY ,PERMITTIVITY - Abstract
For the compounds Cmc2
1 -X2 As2 O (X = Si, Ge, and Sn), the stabilities are verified by the elastic constants and the phonon dispersion spectra. The structural, mechanical, electronic, and optical properties are investigated by using density functional theory (DFT) calculations. For Cmc21 -X2 As2 O, the mechanical strengths in the [100], [010], and [001] directions are studied. Young's modulus for Cmc21 -Ge2 As2 O is more anisotropic than that of Cmc21 -Si2 As2 O and Cmc21 -Sn2 As2 O. The band structures of Cmc21 -Si2 As2 O and Cmc21 -Sn2 As2 O show that they are indirect-bandgap semiconductors with bandgaps of 2.744 and 2.201 eV, by using the HSE06 hybrid functional. Cmc21 -Ge2 As2 O is a direct narrow-bandgap semiconductor with a bandgap of 2.131 eV. The static dielectric constants of Cmc21 -Si2 As2 O and Cmc21 -Sn2 As2 O in the [001] direction are higher than those in the [100] and [010] directions. The static dielectric constant of Cmc21 -Ge2 As2 O in the [001] direction is lower than those in the [100] and [010] directions. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
42. A first-principles study of the properties of two novel Si3P4 phases.
- Author
-
Yang, Ruike, Chai, Bao, Wei, Qun, and Zhang, Dongyun
- Subjects
SILICON compounds ,DENSITY functional theory ,ELASTIC constants ,THERMAL stability ,MODULUS of rigidity ,YOUNG'S modulus ,POISSON'S ratio ,DENSITY of states - Abstract
The structural, elastic, electronic and optical properties of two novel phases Si
3 P4 with tetragonal and orthorhombic structures are studied by first-principles calculations according to density function theory (DFT). For novel structures t-Si3 P4 and o-Si3 P4 , the elastic constants results show that they are mechanically stable. The phonon dispersion spectra confirm that they are dynamically stable. The forming enthalpies prove their thermodynamic stability. The mechanical properties, such as the bulk modulus B, shear modulus G, Pugh ratio k, Young’s modulus E and Poisson’s ratios ν are calculated. The results show that t-Si3 P4 has better anti-deformation ability than o-Si3 P4 , and t-Si3 P4 is harder than o-Si3 P4 . The Poisson’s ratio values of t-Si3 P4 and o-Si3 P4 are 0.16 and 0.35, and the Pugh ratio values, k, are 0.88 and 0.33. For t-Si3 P4 , the Pugh ratio k > 0.57 indicates that it behaves in a brittle manner. For o-Si3 P4 , it owns the better plasticity. The directional dependence of the Young’s modulus indicates that o-Si3 P4 is more anisotropic than t-Si3 P4 . The calculated band structures show that the two novel phases are semiconductors, and the narrow indirect bandgaps are 1.847 and 0.158 eV by using PBE0. The densities of states (DOS) indicate that the P ‘p’ and Si ‘p’ play major roles in two phases total DOS. The results of the optical properties, such as the dielectric functions, absorption spectra, loss functions, refractive index, and so on are given. The static dielectric constants are 5.493 and 12.206, the starting positions of the absorption spectra are approximately at 1.815 and 0.140 eV, and the peaks of loss functions are at 15.503 and 11.763 eV, for t-Si3 P4 and o-Si3 P4 , respectively. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
43. Study of the microstructure and antibacterial properties of MgO with doped defects.
- Author
-
Zhang, Dongyun, Lin, Yaning, Song, Shenhua, Zhang, Peixin, and Mi, Hongwei
- Subjects
MAGNESIUM oxide ,MICROSTRUCTURE ,POINT defects ,METAL inclusions ,ANTIBACTERIAL agents - Abstract
In this paper, in order to effectively utilize salt lake magnesium resources, we focused on a functional material containing magnesium, i.e. magnesium oxide, MgO, which is a type of antibacterial material. Through a first-principles study from the atomic level, the microstructure of MgO containing doped point defects of different elements was studied. The relationship between the microscopic structure of the material and its special antibacterial function was explored. The results are as following: the interstitial impurities in MgO are more helpful than substituted impurities for the improvement of the electronic structure. The analysis of the influence of different doping elements on the microstructure confirmed theoretically that Ag and Cu have the same highly active antimicrobial properties with the same change of microstructure, thereby confirming the relationship between microstructure and antimicrobial activity. The results of the simulations match the experimental results, thereby theoretically demonstrating the relationship between defects and antibacterial activities and providing further insight into the nature of the antibacterial mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
44. High performance of LiMn1-<italic>x</italic>Fe<italic>x</italic>PO4/C (0 ≤ <italic>x</italic> ≤ 0.5) nanoparticles synthesized by microwave-assisted solvothermal method.
- Author
-
Chen, Jie, Zhang, Dongyun, Qiao, Jin, and Chang, Chengkang
- Abstract
High specific energy olivine LiMn
1- Fex POx 4 /C (0 ≤x ≤ 0.5) nanoparticles have been synthesized in 20 min at extremely low temperature 160 °C by microwave-solvothermal method. The obtained cathode materials are orthorhombic solid solutions with size of 30–100 nm. Electrochemical test shows that Fe substitution could significantly increase the initial specific capacity and specific energy, as well as cycling performance and rate capability. LiMn0.8 Fe0.2 PO4 /C exhibits the best reversible specific discharge capacity of 165.9 mA h g−1 and specific discharge energy of 643.1 W h kg−1 at 0.1 C. Its discharge capacity remains 95.7% of its initial value of 129.0 mA h g−1 after 50 cycles at 0.5 C. According to the electrochemical impedance spectroscopic analysis, the performance improvement is mainly attributed to the enhancement of Li+ diffusion coefficient (D Li ) by Fe substitution.D Li is 4.43 × 10−14 and 1.34 × 10−12 cm2 s−1 for LiMnPO4 /C and LiMn0.5 Fe0.5 PO4 /C, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
45. The comparison: photoluminescence and afterglow behavior in CaSnO:Dy and CaSnO:Dy phosphors.
- Author
-
Zhang, Bowen, Shi, Mingming, Zhang, Dongyun, Guo, Yunyun, Chang, Chengkang, and Song, WeiJie
- Subjects
PHOTOLUMINESCENCE ,X-ray diffraction ,X-ray photoelectron spectroscopy ,LUMINESCENCE spectroscopy ,DOPING agents (Chemistry) - Abstract
This paper reports the comparison of photoluminescence and afterglow behavior of Dy in CaSnO and CaSnO phosphors. The samples containing CaSnO and CaSnO were prepared via solid-state reaction. The properties have been characterized and analyzed by utilizing X-ray diffraction (XRD), photoluminescence spectroscope (PLS), X-ray photoelectron spectroscopy (XPS), afterglow spectroscopy (AS) and thermal luminescence spectroscope (TLS). The emission spectra revealed that CaSnO:Dy and CaSnO:Dy phosphors showed different photoluminescence. The CaSnO:Dy phosphor showed a typical F to H energy transition of Dy ions, with three significant emissions centering around 482, 572 and 670 nm. However, the CaSnO:Dy phosphor revealed a broad T → S transitions of Sn ions. The XPS demonstrate the existence of Sn ions in CaSnO phosphor caused by the doping of Dy ions. Both the CaSnO:Dy and CaSnO:Dy phosphors showed a typical triple-exponential afterglow when the UV source switched off. Thermal simulated luminescence study indicated that the persistent afterglow of CaSnO:Dy and CaSnO:Dy phosphors was generated by the suitable electron or hole traps which were resulted from the doping the calcium stannate host with rare-earth ions (Dy). [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
46. False responses of Renilla luciferase reporter control to nuclear receptor TR4.
- Author
-
Zhang, Dongyun, Atlasi, Sam, Patel, Krishna, Zhuang, Zihao, and Heaney, Anthony
- Abstract
Renilla luciferase reporter is a widely used internal control in dual luciferase reporter assay system, where its transcription is driven by a constitutively active promoter. However, the authenticity of the Renilla luciferase response in some experimental settings has recently been questioned. Testicular receptor 4 (TR4, also known as NR2C2) belongs to the subfamily 2 of nuclear receptors. TR4 binds to a direct repeat regulatory element in the promoter of a variety of target genes and plays a key role in tumorigenesis, lipoprotein regulation, and central nervous system development. In our experimental system using murine pituitary corticotroph tumor AtT20 cells to investigate TR4 actions on POMC transcription, we found that overexpression of TR4 resulted in reduced Renilla luciferase expression whereas knockdown TR4 increased Renilla luciferase expression. The TR4 inhibitory effect was mediated by the TR4 DNA-binding domain and behaved similarly to the GR and its agonist, Dexamethasone. We further demonstrated that the chimeric intron, commonly present in various Renilla plasmid backbones such as pRL-Null, pRL-SV40, and pRL-TK, was responsible for TR4's inhibitory effect. The results suggest that an intron-free Renilla luciferase reporter may provide a satisfactory internal control for TR4 at certain dose range. Our findings advocate caution on the use of Renilla luciferase as an internal control in TR4-directed studies to avoid misleading data interpretation. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
47. Modeling of Temperature Field Evolution During Multilayered Direct Laser Metal Deposition.
- Author
-
Zhang, DongYun, Feng, Zhe, Wang, ChengJie, Liu, Zhen, Dong, DongDong, Zhou, Yan, and Wu, Rui
- Subjects
LASER deposition ,MULTILAYERS ,MICROSTRUCTURE ,ENERGY dissipation ,MOLECULAR evolution ,COMPUTER simulation ,TEMPERATURE effect - Abstract
It is of great importance to thoroughly explore the evolving temperature fields of direct laser metal deposition (abbreviated as LMD) in vertical thin wall manufacturing. It is helpful to control the temperature gradient, and even to adjust to forming microstructures and accumulation of residual stress. In this paper, a comprehensive three-dimensional transient model is developed for evolving temperature fields. The manufactured material is DS superalloy Rene80. The laser-powder interaction during the powder flowing process is simulated first, and its possible effect on the temperature field of the melting pool is analyzed. Then a 3D numerical simulation for the evolving temperature field is carried out based on considering transport phenomena during LMD such as the change in phase, powder injection and liquid flow. The applied deposition parameters are derived from experimental investigation with optimized vertical wall manufacturing. The simulated results explain why a balance between heat input and dissipation could form inside the vertical thin wall. These reconstruct the instability at an early phase of the building process without any temperature control unit and exhibit the influence of parameters such as laser power, deposition velocity and laser beam deposition pattern. The simulation results of temperature evolution are consistent with experimental investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
48. Research on the formation mechanism of thermal crack for laser welding of IC 10 alloy.
- Author
-
Li, Jianmin, Zhang, Dongyun, Yi, Denghao, Geng, Shuo, and Feng, Xingtao
- Published
- 2022
- Full Text
- View/download PDF
49. SESN2/sestrin 2 induction-mediated autophagy and inhibitory effect of isorhapontigenin (ISO) on human bladder cancers.
- Author
-
Liang, Yuguang, Zhu, Junlan, Huang, Haishan, Xiang, Daimin, Li, Yang, Zhang, Dongyun, Li, Jingxia, Wang, Yulei, Jin, Honglei, Jiang, Guosong, Liu, Zeyuan, and Huang, Chuanshu
- Published
- 2016
- Full Text
- View/download PDF
50. Electrochemical comparison of LiFeMnCrPO/C and LiMnPO/C cathode materials.
- Author
-
Cai, Yuanyuan, Zhang, Dongyun, Chang, Chengkang, Sheng, Zhaomin, and Huang, Kejun
- Abstract
A comparison of electrochemical performance between LiFeMnCrPO/C and LiMnPO/C cathode materials was conducted in this paper. The cathode samples were synthesized by a nano-milling-assisted solid-state process using caramel as carbon sources. The prepared samples were investigated by XRD, SEM, TEM, energy-dispersive X-ray spectroscopy (EDAX), powder conductivity test (PCT), carbon-sulfur analysis, electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge cycling. The results showed that LiFeMnCrPO/C exhibited high specific capacity and high energy density. The initial discharge capacity of LiFeMnCrPO/C was 163.6 mAh g at 0.1C (1C = 160 mA g), compared to 112.3 mAh g for LiMnPO/C. Moreover, the Fe/Cr-substituted sample showed good cycle stability and rate performance. The capacity retention of LiFeMnCrPO/C was 98.84 % over 100 charge-discharge cycles, while it was only 86.64 % for the pristine LiMnPO/C. These results indicated that Fe/Cr substitution enhanced the electronic conductivity for the prepared sample and facilitated the Li diffusion in the structure. Furthermore, LiFeMnCrPO/C composite presented high energy density (606 Wh kg) and high power density (574 W kg), thus suggested great potential application in lithium ion batteries (LIBs). [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.