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System utility based resource allocation for multi-cell OFDM system

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 14-18,45页

作者： HAO Zhi-jie XU xiao-dong ZHAO Ying-hong TAO xiao-feng LI lin-jun ZHANG Zhong-qi Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Utility based resource allocation strategy in multi-cell orthogonal frequency-division multiplexing （OFDM） system plays a critical role in next generation mobile communication systems. Based on the analysis of risk aversion utility functions, this article proposed the system utility based utility, which is named the customer satisfaction （CS） utility. Compared with the proportional fairness （PF） utility, the CS utility reflects the user demands better, and enables the system to adjust its resource allocation according to both the traffic requirements and the resource situation.

关键词： OFDM resource allocation utility multi-cell

Tumors with macroscopic bile duct thrombi in non-HCC patients:Dynamic multi-phase MSCT findings

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World Journal of Gastroenterology 2012年第11期18卷 1273-1278页

作者： Qing-Yu Liu xiao-feng lin Hal-Gang Li Ming Gao Wei-Dong Zhang Department of Radi-ology Sun Yat-Sen Memorial Hospital Sun Yat-Sen UniversityGuangzhou 510120 Guangdong Province China Department of Pathology Sun Yat-Sen MemorialHospital Sun Yat-Sen University Guangzhou 510120 Guang-dong Province China Department of Radiology Cancer CenterSun Yat-Sen University Guangzhou 510060 Guangdong Prov-ince China

Non-hepatocellular carcinoma （non-HCC） with macroscopic bile duct tumor thrombus （BDTI） formation is rare, few radiological studies have been reported. In this case report, we retrospectively analyzed the imaging findings of three cases of non-HCC with macroscopic BDTT on dynamic enhanced multislice computed tomography （MSCT） scan. One case of primary hepatic carcinosarcoma was presented as a solitary, large welldefined tumor with significant necrotic changes. One case of liver metastasis from colon cancer was presented as a Iobulated, large ill-defined tumor. One case of intraductal oncocytic papillary neoplasm involved the entire pancreas, presented as a cystic and solid mass with multilocular changes （the individual Ioculi were less than 5.0 mm in diameter）. The bile duct was dilated due to expansible growth of the BDFE in all three patients. The BDTT was contiguous with hepatic or pancreatictumor, and both of them showed the same enhancement patterns on dynamic contrast-enhanced computed tomography scan： early enhancement in the hepatic arterial phase and a quick wash out of contrast agent in the portal and equilibrium phases. Macroscopic BDTT- in non-HCC patient is rare, dynamic enhanced MSCT scan may be valuable in the diagnosis of non-HCC with BDTT.

关键词： Liver neoplasms Carcinosarcoma Metas-tasis Pancreatic neoplasms Oncocytic papillary neo-plasm Bile ducts tumor thrombus Computed tomog-raphy X-ray

Graphene-based materials for polymer solar cells

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Chinese Chemical Letters 2016年第8期27卷 1259-1270,1468页

作者： xiao-feng lin Zi-Yan Zhang Zhong-Ke Yuan Jing Li xiao-Fen xiao Wei Hong Xu-Dong Chen Ding-Shan Yu Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education of China School of Chemistry and Chemical EngineeringSun Yat-sen University Key Laboratory of High Performance Polymer-based Composites of Guangdong Province School of Chemistry and Chemical Engineering Sun Yat-sen University

Due to the remarkable electronic,optical,thermal,and mechanical properties,graphene-based materials have shown great potential in a wide range of technique ***,the high transparency,conductivity,flexibility,and abundance make graphene materials highly attractive for polymer solar cells（PSCs）.Graphene-based materials have been regarded as one promising candidate used in various parts in PSCs not only as electrodes,but also as interfacial layers and active layers with an aim to boost the power conversion efficiency of the *** this review,we summarize the recent progress about the design and synthesis of graphene-based materials for efficient PSCs along with the related challenges and future perspectives.

关键词： Graphene Polymer solar cells Electrodes Interfacial layers Active layers

Analysis of the causative factors related to earlier emulsification of silicone oil

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International Journal of Ophthalmology(English edition) 2019年第3期12卷 517-519页

作者： Yao Ni Hao Fang Xia Zhang xiao-feng lin Wen-Jun Guo State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University

The aim of this study is to report and analyze the factors related with earlier occurrence of silicone oil(SO) emulsification in patients underwent pars plana vitrectomy and SO injection in our hospital. We retrospectively reviewed consecutive case series undergone both SO injection and removal in our hospital, and 182 ones were eligible. Possible related independent factors included: macula status(on/off), concomitant phacoemulsification with the surgery of SO tamponading, concomitant status of proliferative vitreoretinopathy, combined surgery of retinotomy, time to have emulsification(<6 mo/≥6 mo after primary SO injection), route of SO injection(anterior/posterior), lens status(aphakic/pseudophakic/phakic), anesthesia(local/general), brands and type of SO, with/without episcleral cryotherapy, with/without hypertension, with/without diabetes, with/without intraoperative use of triamcinolone acetonide. The study revealed that brand and type of SO was the significant factor related with earlier emulsification of SO. Further study was warranted to find out the underlying causes.

关键词： early emulsification pars plana vitrectomy silicone oil

Primary clear cell carcinoma in the liver: CT and MRI findings

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World Journal of Gastroenterology 2011年第7期17卷 946-952页

作者： Qing-Yu Liu Hai-Gang Li Ming Gao xiao-feng lin Yong Li Jian-Yu Chen Department of Radiology The Second Affiliated Hospitalof Sun Yat-sen University Guangzhou 510120 Guangdong Prov-ince China Department of Pathology The Second Affiliated Hospital of Sun Yat-sen University Guangzhou 510120Guangdong Province China

AIM: To retrospectively analyze the computed tomography (CT) and magnetic resonance imaging (MRI) appearances of primary clear cell carcinoma of the liver (PCCCL) and compare the imaging appearances of PCCCL and common type hepatocellular carcinoma (CHCC) to determine whether any differences exist between the two groups. METHODS: Twenty cases with pathologically proven PCCCL and 127 cases with CHCC in the Second Affiliated Hospital of Sun Yat-sen University were included in this study. CT or MRI images from these patients were retrospectively analyzed. The following imaging findings were reviewed: the presence of liver cirrhosis, tumor size, the enhancement pattern on dynamic contrast scanning, the presence of pseudo capsules, tumor rupture, portal vein thrombosis and lymph node metastasis. RESULTS: Both PCCCL and CHCC were prone to occur in patients with liver cirrhosis, the association rate of liver cirrhosis was 80.0% and 78.7%, respectively (P > 0.05). The mean sizes of PCCCL and CHCC tumors were (7.28 ± 4.25) cm and (6.96 ± 3.98) cm, respectively. Small HCCs were found in 25.0% (5/20) of PCCCL and 19.7% (25/127) of CHCC cases. No significant differences in mean size and ratio of small HCCs were found between the two groups (P = 0.658 and 0.803, respectively). Compared with CHCC patients, PCCCL patients were more prone to form pseudo capsules (49.6% vs 75.0%, P = 0.034). Tumor rupture, typical HCC enhancement patterns and portal vein tumor thrombosis were detected in 15.0% (3/20), 72.2% (13/18) and 20.0% (4/20) of patients with PCCCL and 3.1% (4/127), 83.6% (97/116) and 17.3% (22/127) of patients with CHCC, respectively. There were no significant differences between the two groups (all P > 0.05). No patients with PCCCL and 2.4% (3/127) of patients with CHCC showed signs of lymph node metastasis (P > 0.05). CONCLUSION: The imaging characteristics of PCCCL are similar to those of CHCC and could be useful for differentiating these from other liver tumors (such as h

关键词： Clear cell carcinoma Hepatocellular carcinoma Pathology Magnetic resonance imaging Computed Tomography X-ray

Physical activity levels and predictors in patients following percutaneous coronary intervention: a cross-sectional study

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Frontiers of Nursing 2023年第4期10卷 471-480页

作者： xiao-lin feng Shao-Mei Shang Shun-lin Xu Hong-Bo Chen Yun-lin Wang School of Nursing Hunan University of Chinese MedicineChangshaHunan 410208China School of Nursing Peking UniversityBeijing 100191China Cardiac Centre Peking University Third HospitalBeijing 100191China

Objective: To examine physical activity(PA) of post-percutaneous coronary intervention(PCI) patients and explore the demographic, clinical, and social psychological characteristics associated with PA levels. Methods: A total of 246 post-PCI patients from the Peking University Third Hospital in Beijing, China, were included in this crosssectional study through convenience sampling. Data were collected from a self-repor ted questionnaire. PA was categorized into low, moderate, or high levels. The ordinal multinomial logistic regression model was used to estimate the relationship among demographic, medical, and psychosocial characteristics. Results: The overall prevalence of low, moderate, and high PA was 20%, 70%, and 10%, respectively. For the domain-specific PA patterns, most par ticipants took par t in leisure-time PA(84.5%);walking was the most common PA. Increased motivation and selfefficacy, lower monthly income, and unemployment were predictors of high PA. Conclusions: PA levels in post-PCI patients was not optimal, and leisure-time PA had the highest par ticipation rate. Analyses of influencing factors can provide medical staff and health workers information to focus on high-risk groups and introduce more tailored interventions. Future studies can explore more regions, and ecological models can be introduced to study more influencing factors.

关键词： cardiac rehabilitation determinant percutaneous coronary interventions physical activity prevalence

Hepatic focal nodular hyperplasia in children:Imaging features on multi-slice computed tomography

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World Journal of Gastroenterology 2012年第47期18卷 7048-7055页

作者： Qing-Yu Liu Wei-Dong Zhang Dong-Ming Lai Ying Ou-yang Ming Gao xiao-feng lin Department of Radiology Sun Yat-sen Memorial HospitalSun Yat-sen University Department of Radiology Cancer CenterSun Yat-sen University Department of General Surgery Sun Yat-sen Memorial HospitalSun Yat-sen University Department of Pediatrics Sun Yat-sen Memorial HospitalSun Yat-sen University

AIM:To retrospectively analyze the imaging features of hepatic focal nodular hyperplasia(FNH) in children on dynamic contrast-enhanced multi-slice computed tomography(MSCT) and computed tomography angiography(CTA) ***:From September 1999 to April 2012,a total of 218 cases of hepatic FNH were confirmed by either surgical resection or biopsy in the Sun Yat-sen Memorial Hospital of Sun Yat-sen University and the Cancer center of Sun Yat-sen University,including 12 cases(5.5%) of FNH in children(age ≤ 18 years old).All the 12 pediatric patients underwent *** retrospectively analyzed the imaging features of FNH lesions,including the number,location,size,margin,density of FNH demonstrated on pre-contrast and contrastenhanced computed tomography(CT) scanning,central scar,fibrous septa,pseudocapsule,the morphology of the feeding arteries and the presence of draining vessels(portal vein or hepatic vein).RESULTS:All the 12 pediatric cases of FNH had solitary *** maximum diameter of the lesions was 4.0-12.9 cm,with an average diameter of 5.5 ± 2.5 *** majority of the FNH lesions(10/12,83.3%) had well-defined *** scar(10/12,83.3%) and fibrous septa(11/12,91.7%) were commonly found in children with *** scar was either isodense(n = 7) or hypodense(n = 3) on pre-contrast CT images and showed progressive enhancement in 8 cases in the equilibrium *** septa were linear hypodense areas in the arterial phase and isodense in the portal and equilibrium *** was very rare(1/12,8.3%) in pediatric *** the exception of central scars and fibrous septa within the lesions,all 12 cases of pediatric FNH were homogenously enhanced on the contrast-enhanced CT images,significantly hyperdense in the arterial phase(12/12,100.0%),and isodense in the portal venous phase(7/12,58.3%) and equilibrium phase(11/12,91.7%).Central feeding arteries inside the tumors were observed on CTA images for all 12 cases of FNH,whereas no neovascu

关键词： Focal nodular hyperplasia Liver Children Benign hepatic lesions X-ray Computed tomography

SYNTHESIS OF NOVEL THIOPHENEDIMETHYLENE BRIDGED HOMOBINUCLEAR METALLOCENES AND THEIR CATALYTIC PROPERTIES FOR ETHYLENE POLYMERIZATION

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Chinese Journal of Polymer Science 2006年第1期24卷 21-27页

作者： Xi-jie Liu Jun-quan Sun Hai-ying Zhang xiao-hui xiao and feng lin Department of Chemical Engineering,College of Material and Chemical Engineering,Zhejiang University,Hangzhou 310027,China Department of Chemical Engineering College of Material and Chemical Engineering Zhejiang University Hangzhou 310027 China

By treating disodium（thiophenedimethylene）dicyclopentadienide C4H2S（CH2C5H4Na）2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2] （M = Ti 3, M = Zr 4） were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3, 4） reached 2.44 × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3, 4） and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

Intravitreal slow-release dexamethasone alleviates traumatic proliferative vitreoretinopathy by inhibiting persistent inflammation and Müller cell gliosis in rabbits

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International Journal of Ophthalmology(English edition) 2023年第1期16卷 22-32页

作者： Yi-Ming Zhao Rong-Sha Sun Fang Duan Fang-Yu Wang Yu-Jie Li xiao-Bing Qian Jie-Ting Zeng Yao Yang xiao-feng lin State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina Xi’an People’s Hospital(Xi’an Fourth Hospital) Shaanxi Eye HospitalXi’an 710004Shaanxi ProvinceChina

AIM:To evaluate the effects of intravitreal slow-release dexamethasone on traumatic proliferative vitreoretinopathy(PVR)and Müller cell gliosis and preliminarily explored the possible inflammatory mechanism in a rabbit model induced by penetrating ocular ***:Traumatic PVR was induced in the right eyes of pigmented rabbits by performing an 8-mm circumferential scleral incision placed 2.5 mm behind the limbus,followed by treatment with a slow-release dexamethasone implant(Ozurdex)or sham *** eyes were used as normal *** intraocular pressure(IOP)was monitored using an iCare *** severity was evaluated via anatomical and histopathological examinations every week for 6wk;specific inflammatory cytokine and proliferative marker levels were measured by quantitative real-time polymerase chain reaction,Western blot,protein chip analysis,or immunofluorescence ***:During the observation period,PVR severity gradually *** Müller cell gliosis was observed in the peripheral retina near the wound and in the whole retina of PVR *** significantly alleviated PVR development and Müller cell ***-traumatic inflammation fluctuated and was *** interleukin-1β(IL-1β)mRNA level was significantly upregulated,peaking on day 3 and increasing again on day 21 after *** expression of nod-like receptor family pyrin domain containing 3(NLRP3)showed a similar trend that began earlier than that of IL-1β*** suppressed the expression of IL-1β,NLRP3,and phosphorylated nuclear factor-kappa B(NF-κB).The average IOP after treatment was within normal ***:The present study demonstrates chronic and fluctuating inflammation in a traumatic PVR rabbit model over *** treatment significantly inhibites inflammatory cytokines expression and Müller cell gliosis,and thus alleviates PVR *** study highlights the important role of IL-1β,and Ozurdex inhibites inflammation pres

关键词： ocular trauma proliferative vitreoretinopathy gliosis Ozurdex inflammation rabbit