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Treadmill exercise exerts a synergistic effect with bone marrow mesenchymal stem cell-derived exosomes on neuronal apoptosis and synaptic-axonal remodeling 被引量:1
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作者 Xin-Hong Jiang Hang-Feng Li +5 位作者 Man-Li Chen Yi-Xian Zhang Hong-Bin Chen Rong-Hua Chen Ying-Chun Xiao nan liu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1293-1299,共7页
Treadmill exercise and mesenchymal stem cell transplantation are both practical and effective methods for the treatment of cerebral ischemia.However,whether there is a synergistic effect between the two remains unclea... Treadmill exercise and mesenchymal stem cell transplantation are both practical and effective methods for the treatment of cerebral ischemia.However,whether there is a synergistic effect between the two remains unclear.In this study,we established rat models of ischemia/reperfusion injury by occlusion of the middle cerebral artery for 2 hours and reperfusion for 24 hours.Rat models were perfused with bone marrow mesenchymal stem cell-derived exosomes(MSC-exos)via the tail vein and underwent 14 successive days of treadmill exercise.Neurological assessment,histopathology,and immunohistochemistry results revealed decreased neuronal apoptosis and cerebral infarct volume,evident synaptic formation and axonal regeneration,and remarkably recovered neurological function in rats subjected to treadmill exercise and MSC-exos treatment.These effects were superior to those in rats subjected to treadmill exercise or MSC-exos treatment alone.Mechanistically,further investigation revealed that the activation of JNK1/c-Jun signaling pathways regulated neuronal apoptosis and synaptic-axonal remodeling.These findings suggest that treadmill exercise may exhibit a synergistic effect with MSC-exos treatment,which may be related to activation of the JNK1/c-Jun signaling pathway.This study provides novel theoretical evidence for the clinical application of treadmill exercise combined with MSC-exos treatment for ischemic cerebrovascular disease. 展开更多
关键词 apoptosis axonal regeneration c-Jun EXOSOMES functional remodeling ischemic stroke JNK1 mesenchymal stem cells synaptic formation treadmill exercise
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Parity-check and G-matrix based intelligent early stopping criterion for belief propagation decoder for polar codes
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作者 Qasim Jan Shahid Hussain +4 位作者 Zhiwen Pan nan liu Zakir Ali Zechen liu Xiaohu You 《Digital Communications and Networks》 SCIE CSCD 2023年第5期1148-1156,共9页
The error correction performance of Belief Propagation(BP)decoding for polar codes is satisfactory compared with the Successive Cancellation(SC)decoding.Nevertheless,it has to complete a fixed number of iterations,whi... The error correction performance of Belief Propagation(BP)decoding for polar codes is satisfactory compared with the Successive Cancellation(SC)decoding.Nevertheless,it has to complete a fixed number of iterations,which results in high computational complexity.This necessitates an intelligent identification of successful BP decoding for early termination of the decoding process to avoid unnecessary iterations and minimize the computational complexity of BP decoding.This paper proposes a hybrid technique that combines the“paritycheck”with the“G-matrix”to reduce the computational complexity of BP decoder for polar codes.The proposed hybrid technique takes advantage of the parity-check to intelligently identify the valid codeword at an early stage and terminate the BP decoding process,which minimizes the overhead of the G-matrix and reduces the computational complexity of BP decoding.We explore a detailed mechanism incorporating the parity bits as outer code and prove that the proposed hybrid technique minimizes the computational complexity while preserving the BP error correction performance.Moreover,mathematical formulation for the proposed hybrid technique that minimizes the computation cost of the G-matrix is elaborated.The performance of the proposed hybrid technique is validated by comparing it with the state-of-the-art early stopping criteria for BP decoding.Simulation results show that the proposed hybrid technique reduces the iterations by about 90%of BP decoding in a high Signal-to-Noise Ratio(SNR)(i.e.,3.5~4 dB),and approaches the error correction performance of G-matrix and conventional BP decoder for polar codes. 展开更多
关键词 Belief propagation Early termination G-MATRIX Parity-check Polar codes
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Structural, electronic and magnetic properties of Fe-doped strontium ruthenates
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作者 刘楠 王晓超 司良 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期96-104,共9页
By employing a combined approach of density-functional theory(DFT) and dynamical mean-field theory(DMFT) calculations, we examine the structural, electronic, and magnetic characteristics of two distinct strontium ruth... By employing a combined approach of density-functional theory(DFT) and dynamical mean-field theory(DMFT) calculations, we examine the structural, electronic, and magnetic characteristics of two distinct strontium ruthenates: Sr2RuO4,an unconventional superconductor, and the correlated metal SrRuO3, both at 50% Fe-doping level. In both Sr2Fe0.5Ru0.5O4and SrFe0.5Ru0.5O3, the original ruthenium(Ru) and the dopant iron(Fe) atoms adopt 3-dimensional and 2-dimensional G-type structures, respectively. The hybridization between Fe-3d and Ru-4d is comparatively weaker than in other double perovskite systems. The interplay between strong correlations and reduced itinerancy results in significant spin splitting at Fe and Ru sites. Consequently, a charge transfer process, along with the super-exchange effect, leads to antiferromagnetically coupled Fe3+and Ru5+ions and establishes a semiconducting ferrimagnetic order. Subsequent DMFT calculations demonstrate the persistence of the ferrimagnetic order even at room temperature(300 K). These findings align with prior reports on Sr Fe0.5Ru0.5O3, thus reinforcing the notion that 3d–4d transition metal oxides hold considerable promise as candidates for high-performance spintronic devices, such as spin-valve sensors and spintronic giant magnetoresistance devices. 展开更多
关键词 first-principles calculations double perovskites correlation effects dynamical mean-field theory
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Evaluation of the Application Effect of Short Video Combined with BOPPPS Teaching Mode in Clinical Anesthesia Teaching
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作者 Hong Xi Hua Bai +3 位作者 Xianhong Jiang Haiyan Huo Huihui liu nan liu 《Journal of Contemporary Educational Research》 2023年第12期1-7,共7页
Objective:To study the application effect of short video combined with BOPPPS teaching mode in clinical anesthesia practice.Method:48 students assigned to clinical anesthesia in digestive endoscopy of Shanxi Bethune H... Objective:To study the application effect of short video combined with BOPPPS teaching mode in clinical anesthesia practice.Method:48 students assigned to clinical anesthesia in digestive endoscopy of Shanxi Bethune Hospital from July 1,2022 to April 1,2023 were selected as research objects.They were randomly divided into the control group(PowerPoint presentation teaching group)and the observation group(short video combined with BOPPPS teaching group),with 24 students in each group.After the internship,the students’theoretical and technical scores were tested,the effects of the two teaching modes were compared,and the students’satisfaction was investigated.Results:The test scores of students in the observation group were significantly better than those in the control group(P<0.05).The short video combined with BOPPPS teaching mode can significantly improve students’learning interest,operation skills,and memory(P<0.05).The students’satisfaction in the observation group was higher than that in the control group(P<0.05).Conclusion:In clinical practice,the application of short video combined with BOPPPS teaching mode has achieved great effect,which is worth further promotion and research. 展开更多
关键词 Short video combined with BOPPPS teaching model Clinical teaching of anesthesia Teaching effect Teaching evaluation
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1310 nm Source Spectral-Domain Optical Coherence Tomography for Chinese Pigment and Jadeite Research
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作者 Hao Sun Tingting Gang +5 位作者 Manli Hu nan liu Rongxin Tong Xiaobo liu Qunxi Zhang Jianhong Zhou 《Optics and Photonics Journal》 2016年第8期48-52,共5页
Optical Coherence Tomography (OCT) technique is a nondestructive optical detection technology based on low-coherence interferometer and it has become an attractive cultural heritage research method. A 1310 nm source s... Optical Coherence Tomography (OCT) technique is a nondestructive optical detection technology based on low-coherence interferometer and it has become an attractive cultural heritage research method. A 1310 nm source spectral-domain optical coherence tomography (SD-OCT) system based on optical fiber Michelson interferometer and optical spectrum analyzer is proposed and demonstrated for Chinese cultural heritage research. The cross-section OCT images of Chinese pigment samples and jadeite samples can provide a lot of valuable microstructure information for the Chinese cultural heritage research and identification works. 展开更多
关键词 Optical Coherence Tomography Spectral-Domain OCT Cultural Heritage
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组学技术在现代中药药理研究中的应用与思考 被引量:17
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作者 姜云耀 孙明谦 +4 位作者 马博 陈进成 刘楠 刘华 刘建勋 《世界科学技术-中医药现代化》 CSCD 北大核心 2018年第8期1287-1295,共9页
中医药的功效在日常临床实践中被不断地展现出来,它在改善人类健康状况以及预防和治疗疾病方面也越来越受到全世界的认可和欢迎。然而,中医药理念与现代药理学存在根本的差异,极大地阻碍了中药现代化的发展。近年来,组学技术在中药研究... 中医药的功效在日常临床实践中被不断地展现出来,它在改善人类健康状况以及预防和治疗疾病方面也越来越受到全世界的认可和欢迎。然而,中医药理念与现代药理学存在根本的差异,极大地阻碍了中药现代化的发展。近年来,组学技术在中药研究中的应用备受关注,包括基因组学、转录组学、蛋白组学和代谢组学等组学技术开始被应用于中药的研究。组学的研究不仅要强调一般水平或仅限于单一方面,多组学间应该结合起来,合理整合、科学分析将更有助于系统深入地揭示中药功效的物质基础和作用机制。目前,多组学联合应用对中药作用机制的研究正处于起步阶段,研究深度不够,仅仅是表面结果和现象的结合,还未达到真正的融合。如何把多组学技术进行合理的融合和恰当的对接,共同为揭示中医药的科学含义服务,是一项值得深入思考的课题。多组学技术联合网络药理学和生物信息学的方法来阐释中药多组分在分子水平的协同作用,再结合整体水平中药作用机制的研究,能够帮助我们更精确地揭示中药的药理学机制。 展开更多
关键词 基因组学 转录组学 蛋白组学 代谢组学 网络药理学 多组学联合
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微创玻璃体切除术中及术后脉络膜脱离的原因及治疗 被引量:4
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作者 赵彭彭 刘楠 +2 位作者 程岩 王爽 赵劲松 《国际眼科杂志》 CAS 北大核心 2018年第1期76-79,共4页
无缝线微创玻璃体切除术的应用已有10余年,高速切割和精细器械的应用有效治疗严重的玻璃体视网膜疾病,但术中及术后的并发症也严重影响视力恢复,其中脉络膜脱离是微创玻璃体切除术中及术后比较少见的并发症,可继发青光眼、视力下降等。
关键词 微创玻璃体切除术 脉络膜脱离 并发症
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Influences of blood lipids on the occurrence and prognosis of hemorrhagic transformation after acute cerebral infarction: a case-control study of 732 patients 被引量:60
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作者 Gang Lv Guo-Qiang Wang +5 位作者 Zhen-Xi Xia Hai-Xia Wang nan liu Wei Wei Yong-Hua Huang Wei-Wei Zhang 《Military Medical Research》 SCIE CAS CSCD 2019年第3期189-200,共12页
Background: To study the influence of blood lipid levels on hemorrhagic transformation(HT) and prognosis after acute cerebral infarction(ACI).Methods: Patients with ACI within 72 h of symptoms onset between January 1 ... Background: To study the influence of blood lipid levels on hemorrhagic transformation(HT) and prognosis after acute cerebral infarction(ACI).Methods: Patients with ACI within 72 h of symptoms onset between January 1 st, 2015, and December 31 st, 2016, were retrospectively analyzed. Patients were divided into group A(without HT) and group B(HT). The outcomes were assessed after 3 months of disease onset using the modified Rankin Scale(m RS). An m RS score of 0–2 points indicated excellent prognosis, and an m RS score of 3–6 points indicated poor prognosis.Results: A total of 732 patients conformed to the inclusion criteria, including 628 in group A and 104 in group B. The incidence of HT was 14.2%, and the median onset time was 2 d(interquartile range, 1–7 d). The percentages of patients with large infarct size and cortex involvement in group B were 80.8% and 79.8%, respectively, which were both significantly higher than those in group A(28.7 and 33.4%, respectively). The incidence rate of atrial fibrillation(AF) in group B was significantly higher than that in group A(39.4% vs. 13.9%, P<0.001). The adjusted multivariate analysis results showed that large infarct size, cortex involvement and AF were independent risk factors of HT, while total cholesterol(TC) was a protective factor of HT(OR=0.359, 95% CI 0.136–0.944, P=0.038). With every 1 mmol/L reduction in normal TC levels, the risk of HT increased by 64.1%. The mortality and morbidity at 3 months in group B(21.2% and 76.7%, respectively) were both significantly higher than those in group A(8.0% and 42.8%, respectively). The adjusted multivariate analysis results showed that large infarct size(OR=12.178, 95% CI 5.390–27.516, P<0.001) was an independent risk factor of long-term unfavorable outcomes, whereas low-density lipoprotein cholesterol(LDL-C) was a protective factor(OR=0.538, 95% CI 0.300–0.964, P=0.037). With every 1 mmol/L reduction in normal LDL-C levels, the risk of an unfavorable outcome increased by 46.2%. Major therapies, including intravenous recombinant human tissue plasminogen activator(r TPA), intensive lipid-lowering statins and anti-platelets, were not significantly related to either HT or long-term, post-ACI poor prognosis.Conclusions: For patients with large infarct sizes, especially those with cortex involvement, AF, or lower levels of TC, the risk of HT might increase after ACI. The risk of a long-term unfavorable outcome in these patients might increase with a reduction in LDL-C. 展开更多
关键词 Acute cerebral infarction HEMORRHAGIC transformation Total cholesterol LOW-DENSITY LIPOPROTEIN Intensive LIPID-LOWERING STATINS ANTI-PLATELET Atrial fibrillation modified Rankin scale
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二维材料最新研究进展 被引量:9
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作者 常诚 陈伟 +64 位作者 陈也 陈永华 陈雨 丁峰 樊春海 范红金 范战西 龚成 宫勇吉 何其远 洪勋 胡晟 胡伟达 黄维 黄元 季威 李德慧 李连忠 李强 林立 凌崇益 刘鸣华 刘楠 刘庄 Kian Ping Loh 马建民 缪峰 彭海琳 邵明飞 宋礼 苏邵 孙硕 谭超良 唐智勇 王定胜 王欢 王金兰 王欣 王欣然 Andrew T.S.Wee 魏钟鸣 吴宇恩 吴忠帅 熊杰 熊启华 徐伟高 尹鹏 曾海波 曾志远 翟天佑 张晗 张辉 张其春 张铁锐 张翔 赵立东 赵美廷 赵伟杰 赵运宣 周凯歌 周兴 周喻 朱宏伟 张华 刘忠范 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第12期1-151,共151页
Research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since ... Research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since the mechanical exfoliation of graphene in 2004. Starting from graphene, 2D materials now have become a big family with numerous members and diverse categories. The unique structural features and physicochemical properties of 2D materials make them one class of the most appealing candidates for a wide range of potential applications. In particular, we have seen some major breakthroughs made in the field of 2D materials in last five years not only in developing novel synthetic methods and exploring new structures/properties but also in identifying innovative applications and pushing forward commercialisation. In this review, we provide a critical summary on the recent progress made in the field of 2D materials with a particular focus on last five years. After a brief backgroundintroduction, we first discuss the major synthetic methods for 2D materials, including the mechanical exfoliation, liquid exfoliation, vapor phase deposition, and wet-chemical synthesis as well as phase engineering of 2D materials belonging to the field of phase engineering of nanomaterials(PEN). We then introduce the superconducting/optical/magnetic properties and chirality of 2D materials along with newly emerging magic angle 2D superlattices. Following that, the promising applications of 2D materials in electronics, optoelectronics, catalysis, energy storage, solar cells, biomedicine, sensors, environments, etc. are described sequentially. Thereafter, we present the theoretic calculations and simulations of 2D materials. Finally, after concluding the current progress, we provide some personal discussions on the existing challenges and future outlooks in this rapidly developing field. 展开更多
关键词 Two-dimensional materials Transition metal dichalcogenides Phase engineering of nanomaterials ELECTRONICS OPTOELECTRONICS CATALYSIS Energy storage and conversion
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Correlating interleukin-10 promoter gene polymorphisms with human cerebral infarction onset 被引量:7
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作者 Xin-hong Jiang Ke-xu Lin +2 位作者 Yi-xian Zhang Rong-hua Chen nan liu 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第11期1809-1813,共5页
Evidence suggests that interleukin-10(IL-10) deficiency exacerbates inflammation and worsens the outcome of brain ischemia. In view of the critical role of the single nucleotide polymorphic sites-1082(A/G) and-819(C/T... Evidence suggests that interleukin-10(IL-10) deficiency exacerbates inflammation and worsens the outcome of brain ischemia. In view of the critical role of the single nucleotide polymorphic sites-1082(A/G) and-819(C/T) in the promoter region of the IL-10 gene, we hypothesized that they are associated with cerebral infarction morbidity in the Chinese Han population. We genotyped these allelic gene polymorphisms by amplification refractory mutation system-polymerase chain reaction methods in 181 patients with cerebral infarction(cerebral infarction group) and 115 healthy subjects(control group). We identified significant differences in genotype distribution and allele frequency of the IL-10-1082 A/G allele between cerebral infarction and control groups(χ2 = 6.643, P = 0.010). The IL-10-1082 A allele frequency was significantly higher in the cerebral infarction group(92.3%) than in the control group(86.1%)(P = 0.015). Moreover, cerebral infarction risk of the AA genotype was 2-fold higher than with the AG genotype(OR = 2.031, 95%CI: 1.134–3.637). In addition, AA genotype together with hypertension was the independent risk factor of cerebral infarction(OR = 2.073, 95%CI: 1.278–3.364). No statistical difference in genotype distribution or allele frequency of IL-10-819 C/T was found between cerebral infarction and control groups(P > 0.05). These findings suggest that the IL-10-1082 A/G gene polymorphism is involved in cerebral infarction, and increased A allele frequency is closely associated with occurrence of cerebral infarction. 展开更多
关键词 等位基因多态性 白细胞介素-10 基因启动子区 脑缺血 发病 等位基因频率 IL-10 单核苷酸多态性
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Coverage Optimization of LTE Networks Based on Antenna Tilt Adjusting Considering Network Load 被引量:4
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作者 NhuQuan Phan ThiOanh Bui +3 位作者 Huilin Jiang Pei Li Zhiwen Pan nan liu 《China Communications》 SCIE CSCD 2017年第5期48-58,共11页
In this paper,we investigate the coverage optimization for LTE networks considering the network load. The network coverage is defined as the number of served users of evolved Node B(eNB)which is determined by e NBs... In this paper,we investigate the coverage optimization for LTE networks considering the network load. The network coverage is defined as the number of served users of evolved Node B(eNB)which is determined by e NBs' antenna tilt angles(ATA). The coverage is optimized by optimizing the number of served users based on the Modified Particle Swarm Optimization(MPSO)algorithm. Simulation results show that both the number of served users by each e NB and the system throughput are significantly increased. As well,the average load and the bandwidth efficiency of the network are improved. 展开更多
关键词 LTE networks antenna tilt angle coverage optimization and modified particle swarm optimization
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Hemophagocytic lymphohistiocytosis caused by STAT1 gain-offunction mutation is not driven by interferon-γ:A case report 被引量:3
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作者 nan liu Fen-Ying Zhao Xiao-Jun Xu 《World Journal of Clinical Cases》 SCIE 2020年第23期6130-6135,共6页
BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a life-threatening hyperinflammatory syndrome caused by many genetic defects.STAT1 is a DNAbinding factor that regulates gene transcription.HLH caused by STAT1 gain... BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a life-threatening hyperinflammatory syndrome caused by many genetic defects.STAT1 is a DNAbinding factor that regulates gene transcription.HLH caused by STAT1 gain-offunction(GOF)mutations has rarely been reported and its clinical manifestations and mechanisms are not clearly defined.CASE SUMMARY A 2-year-old boy presented to our hospital with recurrent fever for>20 d.The patient had a personal history of persistent oral candidiasis and inoculation site infection during the past 2 years.Hepatosplenomegaly was noted.Complete blood cell count showed severe anemia,thrombocytopenia and neutropenia.Other laboratory tests showed liver dysfunction,hypertriglyceridemia and decreased fibrinogen.Hemophagocytosis was found in the bone marrow.Chest computed tomography showed a cavitary lesion.Tests for fungal infection were positive.Serum T helper(Th)1/Th2 cytokine determination demonstrated moderately elevated levels of interleukin(IL)-6 and IL-10 with normal interferon(IFN)-γconcentration.Mycobacterium bovis was identified in bronchoalveolar lavage fluid by polymerase chain reaction.Genetic testing identified a heterozygous mutation of c.1154C>T causing a T385M amino acid substitution in STAT1.Despite antibacterial and antifungal therapy,the febrile disease was not controlled.The signs of HLH were relieved after HLH-94 protocol administration,except fever.Fever was not resolved until he received anti-tuberculosis therapy.Hematopoietic stem cell transplantation was refused and the patient died six months later due to severe pneumonia.CONCLUSION Patients with STAT1 GOF mutation have broad clinical manifestations and may develop HLH.This form of HLH presents with normal IFN-γlevel without cytokine storm. 展开更多
关键词 Hemophagocytic lymphohistiocytosis Signal transducer and activator of transcription 1 GAIN-OF-FUNCTION Interferon gamma Mycobacterial disease Case report
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Innovative color jet 3D printing of levetiracetam personalized paediatric preparations 被引量:2
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作者 Zengming Wang Xiaolu Han +6 位作者 Ruxin Chen Jingru Li Jing Gao Hui Zhang nan liu Xiang Gao Aiping Zheng 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第3期374-386,共13页
3D printing is a promising technology used in the fabrication of complex oral dosage delivery pharmaceuticals.This study first reports an innovative color jet 3D printing(CJ-3DP)technology to produce colorful cartoon ... 3D printing is a promising technology used in the fabrication of complex oral dosage delivery pharmaceuticals.This study first reports an innovative color jet 3D printing(CJ-3DP)technology to produce colorful cartoon levetiracetam pediatric preparations with high accuracy and reproducibility.For this study,the ideal printing ink consisted of 40%(v/v)isopropanol aqueous solution containing 0.05%(w/w)polyvinylpyrrolidone and 4%(w/w)glycerin,which was satisfied with scale-up of the production.The external and internal spatial structures of the tablets were designed to control the appearance and release,and cartoon tablets with admirable appearances and immediate release characteristics were printed.The dosage model showed a good linear relationship between the model volume and the tablet strength(r>0.999),which proved the potential of personalized administration.The surface roughness indicated that the appearance of the CJ-3DP tablets was significantly better than the first listed 3D printed drug(Spritam R).Moreover,the scanning electron microscopy and porosity results further showed that the tablets have a structure of loose interior and tight exterior,which could ensure good mechanical properties and rapid dispersion characteristics simultaneously.In conclusion,the innovative CJ-3DP technology can be used to fabricate personalized pediatric preparations for improved compliance.Due to the stable formulation and fabrication process,this technology has the potential in scale-up production. 展开更多
关键词 Color jet 3D printing Paediatric preparations Personalized administration Medicine dosage model Immediate release
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Numerical Investigation of the Deposition Characteristics of Snow on the Bogie of a High-Speed Train 被引量:2
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作者 Lu Cai Zhen Lou +2 位作者 nan liu Chao An Jiye Zhang 《Fluid Dynamics & Materials Processing》 EI 2020年第1期41-53,共13页
To investigate the deposition distribution of snow particles in the bogie surfaces of a high-speed train,a snow particle deposition model,based on the critical capture velocity and the critical shear velocity,was elab... To investigate the deposition distribution of snow particles in the bogie surfaces of a high-speed train,a snow particle deposition model,based on the critical capture velocity and the critical shear velocity,was elaborated.Simulations based on the unsteady Reynolds-Averaged Navier-Stokes(RANS)approach coupled with Discrete Phase Model(DPM)were used to analyze the motion of snow particles.The results show that the cross beam of the bogie frame,the anti-snake damper,the intermediate brake clamps in the rear wheels,the traction rod and the anti-rolling torsion bar are prone to accumulate snow.The accumulation mass relating to the vertical surface in the rear region,horizontal surface in the front region and the corner area of the bogie is high.The average snow accumulation mass for each component ordered from high to low is as follow:traction rod,frame,bolster,brake clamp 2,anti-rolling torsion bar,brake clamp 1,transverse damper,axle box 2,axle box 1,air spring,anti-snake damper,tread cleaning device.The snow accumulation mass on the front components of the bogie is more significant than that relating to the rear components.Particularly,the average snow accumulation mass of rear brake clamp 2 and axle box 2 is about twice as high as that of the front brake clamp 1 and axle box 1. 展开更多
关键词 High-speed train BOGIE discrete phase model snow drift snow accumulation
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Mn-doped topological insulators: a review 被引量:1
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作者 Jing Teng nan liu Yongqing Li 《Journal of Semiconductors》 EI CAS CSCD 2019年第8期64-80,共17页
Topological insulators (TIs) host robust edge or surface states protected by time-reversal symmetry (TRS), which makes them prime candidates for applications in spintronic devices. A promising avenue of research for t... Topological insulators (TIs) host robust edge or surface states protected by time-reversal symmetry (TRS), which makes them prime candidates for applications in spintronic devices. A promising avenue of research for the development of functional TI devices has involved doping of three-dimensional (3D) TI thin film and bulk materials with magnetic elements. This approach aims to break the TRS and open a surface band gap near the Dirac point. Utilizing this gapped surface state allows for a wide range of novel physical effects to be observed, paving a way for applications in spintronics and quantum computation. This review focuses on the research of 3D TIs doped with manganese (Mn). We summarize major progress in the study of Mn doped chalcogenide TIs, including Bi2Se3, Bi2Te3, and Bi2(Te,Se)3. The transport properties, in particular the anomalous Hall effect, of the Mn-doped Bi2Se3 are discussed in detail. Finally, we conclude with future prospects and challenges in further studies of Mn doped TIs. 展开更多
关键词 TOPOLOGICAL insulators THIN films electron transport ANOMALOUS HALL effect magnetic DOPING
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Analysis of Coverage and Area Spectrum Efficiency of UDN with Inter-Tier Dependence 被引量:1
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作者 Kaichuang Wang Pei Li +3 位作者 Fei Ding Zhiwen Pan nan liu Xiaohu You 《China Communications》 SCIE CSCD 2019年第3期154-164,共11页
Stochastic geometry is widely employed to model cellular network. But in most existing works, base stations(BSs) are modelled following a homogeneous Poisson point process(PPP) for one-tier network, or several indepen... Stochastic geometry is widely employed to model cellular network. But in most existing works, base stations(BSs) are modelled following a homogeneous Poisson point process(PPP) for one-tier network, or several independent homogeneous PPP for multi-tier network, which ignore the dependence among BSs. In this paper, a three-tier UDN(Ultra dense network) with Macrocell BSs(MBS) for basic coverage, Picocell BSs(PBSs) deployed outside the coverage area of MBSs for compensating coverage holes, and Femtocell BSs(FBSs) surrounding MBSs for capacity improvement modelled by point process with inter-tier dependence is proposed. The tier association probability, the coverage probability and area spectrum efficiency(ASE) are derived. Simulation results validate our derivation, and results show that the proposed network model has 25%-45% performance gain in ASE. 展开更多
关键词 stochastic geometry tier association PROBABILITY POISSON HOLE process area spectrum EFFICIENCY COVERAGE PROBABILITY
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Downlink SINR and Rate Distribution of Ultra-Dense Het Nets with Burst Traffic 被引量:1
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作者 Xin liu Zhiwen Pan +1 位作者 nan liu Xiaohu You 《China Communications》 SCIE CSCD 2016年第9期24-32,共9页
SINR distribution and rate overage distribution are crucial for optimization of deployment of Ultra-dense Het Nets.Most existing literatures assume that BSs have full queues and full-buffer traffic.In fact,due to ultr... SINR distribution and rate overage distribution are crucial for optimization of deployment of Ultra-dense Het Nets.Most existing literatures assume that BSs have full queues and full-buffer traffic.In fact,due to ultra-dense deployment of small cells,traffic in small cell varies dramatically in time and space domains.Hence,it is more practical to investigate scenario with burst traffic.In this paper,we consider a two-tier non-uniform ultra-dense Het Net with burst traffic,where macro BSs are located according to Poisson Point Process(PPP),and pico BSs are located according to Poisson Hole Process(PHP).The closed-form expressions of SINR distribution and rate distribution are derived,and then validated through simulation.Our study shows that different from the result of full buffer case,the SINR distribution and rate distribution of users depend on the average transmission probabilities of BSs in burst traffic case. 展开更多
关键词 流量分布 密集 SINR 速度分布 超高密度 封闭形式 仿真验证 BSS
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Clinical Implications of HER-2 and P53 in Taxane-Based and Anthracycline-Based Neoadjuvant Chemotherapy in Breast Cancer 被引量:2
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作者 Xiaolan Wang Fan Yao +6 位作者 nan liu Yunfei Wu Xinyu Zheng Jiguang Li Caigang liu Xueshan Qiu Feng Jin 《Chinese Journal of Clinical Oncology》 CSCD 2008年第6期424-428,共5页
OBJECTIVE To evaluate the predictive value of humanepidermal growth factor receptor-2 (HER-2) and P53 in taxane-based and anthracycline-based neoadjuvant chemotherapy (NAC)in breast cancer.METHODSSixty-two patients wi... OBJECTIVE To evaluate the predictive value of humanepidermal growth factor receptor-2 (HER-2) and P53 in taxane-based and anthracycline-based neoadjuvant chemotherapy (NAC)in breast cancer.METHODSSixty-two patients with breast cancer wereincluded in this study.Twenty-two patients were treated withtaxane-based (taxane group) and 40 with anthracycline-based(anthracycline group).ER,PR,c-erbB2 and P53 were detected byimmunohistochemistry staining before NAC,and FluorescenceIn Situ Hybridization(FISH) was used to detect the HER-2 geneamplification for the cases with the expression of c-erbB2 proteinas (++) or (+++).The efficacy of the regimens was evaluated afterNAC.RESULTS In the anthracycline group,objective response (OR)was observed in 30 out of 40 patients (75%),whereas no response(NR) was observed in 10 patients (25%).In the taxane group,ORwas observed in 15 patients out of 22 patients (68.2%),whereasNR was observed in 7 patients (31.8%).HER-2-negative status wascorrelated with a high OR in both taxane-based and anthracycline-based NAC (P = 0.023 and P = 0.029),whereas P53-negative statuswas correlated with high OR rate in anthracycline-based NAC (P= 0.041).The significant difference of the CR rates was observedbetween the patients took<4 cycles and>4 cycles NAC (4.65% vs.21.05%,P<0.05).CONCLUSION The patients with HER-2 gene non-amplicationmay be sensitive to both taxane-based and anthracycline-basedchemotherapy;the patients without P53 overexpression maysuitable to select anthracycline-based chemotherapy;and properincreased NAC cycles may increase CR rates. 展开更多
关键词 化学疗法 乳腺癌 临床 患者
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Potential dynamic analysis of tumor suppressor p53 regulated by Wip1 protein 被引量:1
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作者 刘楠 王丹妮 +2 位作者 刘海英 杨红丽 杨联贵 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期577-582,共6页
The tumor suppressor p53 plays a key role in protecting genetic integrity. Its dynamics have important physiological significance, which may be related to the cell fate. Previous experiments have shown that the wild-t... The tumor suppressor p53 plays a key role in protecting genetic integrity. Its dynamics have important physiological significance, which may be related to the cell fate. Previous experiments have shown that the wild-type p53-induced phosphatase 1(Wip1) protein could maintain p53 oscillation. Therefore, we add Wip1 to remodel the p53 network. Firstly,we use the binomial τ-leap algorithm to prove our model stable under internal noise. Then, we make a series of bifurcation diagrams, that is, p53 levels as a function of p53 degradation rate at different Wip1 generation rates. The results illustrate that Wip1 is essential for p53 oscillation. Finally, a two-dimensional bifurcation diagram is made and the stability of some p53 dynamics under external noise is analyzed by potential landscape. Our results may have some implications for artificially interfering with p53 dynamics to achieve tumor suppression. 展开更多
关键词 WIP1 p53-dynamics OSCILLATION
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Selective control by posterior spinal nerve roots of micturition and erection in rats
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作者 Wenting Wang Mouwang Zhou +2 位作者 Genying Zhu Tao Li nan liu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第35期2749-2754,共6页
The posterior rootlets in L6 and S1 spinal cord of adult male Sprague-Dawley rats underwent electrostimulation. The bladder pressure, urethral perfusion pressure and intracavernous pressure were recorded. When some po... The posterior rootlets in L6 and S1 spinal cord of adult male Sprague-Dawley rats underwent electrostimulation. The bladder pressure, urethral perfusion pressure and intracavernous pressure were recorded. When some posterior rootlets of L6 and S1 were electrostimulated, the intracavernous pressure peaked rapidly, but the bladder pressure and the urethral perfusion pressure curve did not show great change. When other rootlets were stimulated, the bladder pressure changed greatly, but the urethral perfusion pressure and the intracavernous pressure did not show great change. When different rootlets were stimulated, the urethral perfusion pressure changed maximally, but there were no great changes in bladder pressure or intracavernous pressure. Furthermore, stimulation of some rootlets produced simultaneous changes in two or three different pressure measures mentioned above. The results demonstrate that regulation by L6 and S1 posterior rootlets of the rat bladder detrusor, external urethral sphincter and penis cavernous body are significantly distinct. Different rootlets can be distinguished by electrostimulation. 展开更多
关键词 SD大鼠 选择性控制 神经 脊髓 排尿 阴茎海绵体 内压力 电刺激
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