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“教与学”优化算法研究综述 被引量:39
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作者 拓守恒 雍龙泉 邓方安 《计算机应用研究》 CSCD 北大核心 2013年第7期1933-1938,共6页
简要分析了群智能优化算法的研究现状,重点对"教与学"优化算法作了详细的描述,并分析了"教与学"算法的性能及其优缺点;随后介绍了几种改进的"教与学"优化算法,对"教与学"优化算法的应用研究情... 简要分析了群智能优化算法的研究现状,重点对"教与学"优化算法作了详细的描述,并分析了"教与学"算法的性能及其优缺点;随后介绍了几种改进的"教与学"优化算法,对"教与学"优化算法的应用研究情况进行了论述。最后,说明了目前"教与学"优化算法中存在的问题,并指出"教与学"优化算法未来的研究方向。 展开更多
关键词 “教与学”优化算法 “教”阶段 “学”阶段
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From diagnosis to treatment of hepatocellular carcinoma: An epidemic problem for both developed and developing world 被引量:52
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作者 Dimitrios Dimitroulis Christos Damaskos +12 位作者 Serena Valsami Spyridon Davakis Nikolaos Garmpis Eleftherios Spartalis Antonios Athanasiou Demetrios Moris Stratigoula Sakellariou Stylianos Kykalos Gerasimos Tsourouflis Anna Garmpi Ioanna Delladetsima Konstantinos Kontzoglou Gregory Kouraklis 《World Journal of Gastroenterology》 SCIE CAS 2017年第29期5282-5294,共13页
Hepatocellular carcinoma(HCC) is the most frequent primary liver malignancy and the third cause of cancer-related death in the Western Countries. The well-established causes of HCC are chronic liver infections such as... Hepatocellular carcinoma(HCC) is the most frequent primary liver malignancy and the third cause of cancer-related death in the Western Countries. The well-established causes of HCC are chronic liver infections such as hepatitis B virus or chronic hepatitis C virus, nonalcoholic fatty liver disease, consumption of aflatoxins and tobacco smocking. Clinical presentation varies widely; patients can be asymptomatic while symptomatology extends from right upper abdominal quadrant paint and weight loss to obstructive jaundice and lethargy. Imaging is the first key and one of the most important aspects at all stages of diagnosis, therapy and follow-up of patients with HCC. The Barcelona Clinic Liver Cancer Staging System remains the most widely classification system used for HCC management guidelines. Up until now, HCC remains a challenge to early diagnose, and treat effectively; treating management is focused on hepatic resection, orthotopic liver transplantation, ablative therapies, chemoembolization and systemic therapies with cytotocix drugs, and targeted agents. This review article describes the current evidence on epidemiology, symptomatology, diagnosis and treatment of hepatocellular carcinoma. 展开更多
关键词 HEPATOCELLULAR Cancer EPIDEMIOLOGY TREATMENT DIAGNOSIS STAGING Transplantation
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Gd-EOB-DTPA-enhanced magnetic resonance imaging features of hepatic hemangioma compared with enhanced computed tomography 被引量:19
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作者 Akihiro Tateyama Yoshihiko Fukukura +4 位作者 Koji Takumi Toshikazu Shindo Yuichi Kumagae Kiyohisa Kamimura Masayuki Nakajo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第43期6269-6276,共8页
AIM:To clarify features of hepatic hemangiomas on gadolinium-ethoxybenzyl-diethylenetriaminpentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) compared with enhanced computed tomography (CT). METH... AIM:To clarify features of hepatic hemangiomas on gadolinium-ethoxybenzyl-diethylenetriaminpentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) compared with enhanced computed tomography (CT). METHODS:Twenty-six patients with 61 hepatic hem- angiomas who underwent both Gd-EOB-DTPA-enhanced MRI and enhanced CT were retrospectively reviewed. Hemangioma appearances (presence of peripheral nodular enhancement, central nodular enhancement, diffuse homogenous enhancement, and arterioportal shunt during the arterial phase, fill-in enhancement during the portal venous phase, and prolonged enhancement during the equilibrium phase) on Gd-EOB-DTPA-enhanced MRI and enhanced CT were evaluated.The degree of contrast enhancement at the enhancing portion within the hemangioma was visually assessed using a five-point scale during each phase. For quantitative analysis, the tumor-muscle signal intensity ratio (SIR), the liver-muscle SIR, and the attenuation value of the tumor and liver parenchyma were calculated. The McNemar test and the Wilcoxon's signed rank test were used to assess the significance of differences in the appearances of hemangiomas and in the visual grade of tumor contrast enhancement between Gd-EOB-DTPA-enhanced MRI and enhanced CT. RESULTS:There was no significant difference between Gd-EOB-DTPA-enhanced MRI and enhanced CT in the presence of peripheral nodular enhancement (85% vs 82%), central nodular enhancement (3% vs 3%), diffuse enhancement (11% vs 16%), or arterioportal shunt (23% vs 34%) during arterial phase, or fill-in enhancement (79% vs 80%) during portal venous phase. Prolonged enhancement during equilibrium phase was observed less frequently on Gd-EOB-DTPA-enhanced MRI than on enhanced CT (52% vs 100%, P < 0.001). On visual inspection, there was significantly less contrast enhancement of the enhancing portion on Gd-EOB-DTPA-enhanced MRI than on enhanced CT during the arterial (3.94 ± 0.98 vs 4.57 ± 0.64, respectively, P < 0.001), portal venous (3.72 ± 0.82 vs 4.36 ± 0.53, respectively, P < 0.001), and equilibrium phases (2.01 ± 0.95 vs 4.04 ± 0.51, respectively, P < 0.001). In the quantitative analysis, the tumor-muscle SIR and the liver-muscle SIR observed with Gd-EOB-DTPA-enhanced MRI were 0.80 ± 0.24 and 1.28 ± 0.33 precontrast, 1.92 ± 0.58 and 1.57 ± 0.55 during the arterial phase, 1.87 ± 0.44 and 1.73 ± 0.39 during the portal venous phase, 1.63 ± 0.41 and 1.78 ± 0.39 during the equilibrium phase, and 1.10 ± 0.43 and 1.92 ± 0.50 during the hepatobiliary phase, respectively. The attenuation values in the tumor and liver parenchyma observed with enhanced CT were 40.60 ± 8.78 and 53.78 ± 7.37 precontrast, 172.66 ± 73.89 and 92.76 ± 17.92 during the arterial phase, 152.76 ± 35.73 and 120.12 ± 18.02 during the portal venous phase, and 108.74 ± 18.70 and 89.04 ± 7.25 during the equilibrium phase, respectively. Hemangiomas demonstrated peak enhancement during the arterial phase, and both the SIR with Gd-EOB-DTPA-enhanced MRI and the attenuation value with enhanced CT decreased with time. The SIR of hemangiomas was lower than that of liver parenchyma during the equilibrium and hepatobiliary phases on Gd-EOB-DTPA-enhanced MRI. However, the attenuation of hemangiomas after contrast injection was higher than that of liver parenchyma during all phases of enhanced CT. CONCLUSION:Prolonged enhancement during the equilibrium phase was observed less frequently on Gd-EOB-DTPA-enhanced MRI than enhanced CT, which may exacerbate differentiating between hemangiomas and malignant tumors. 展开更多
关键词 Liver HEMANGIOMA Magnetic resonance imaging Gadolinium-ethoxybenzyl-diethylenetriamin-pentaacetic acid Multidetector-row computed tomography
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Why women see differently from the way men see? A review of sex differences in cognition and sports 被引量:3
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作者 Rena Li 《Journal of Sport and Health Science》 SCIE 2014年第3期155-162,共8页
The differences of learning and memory between males and females have been well documented and confirmed by both human and animal studies. The sex differences in cognition started from early stage of neuronal developm... The differences of learning and memory between males and females have been well documented and confirmed by both human and animal studies. The sex differences in cognition started from early stage of neuronal development and last through entire lifespan. The major biological basis of the gender-dependent cognitive activity includes two major components: sex hormone and sex-related characteristics, such as sex- determining region of the Y chromosome (SRY) protein. However, the knowledge of how much biology of sex contributes to normal cogni- tive function and elite athletes in various sports are still pretty limited. In this review, we will be focusing on sex differences in spatial learning and memory -- especially the role of male- and female-type cognitive behaviors in sports. 展开更多
关键词 Brain HORMONES Learning and memory in sports Sex-specific cognition
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Morphological changes and allometric growth in hatcheryreared Chinese loach Paramisgurnus dabryanus(Dabry de Thiersant, 1872) 被引量:11
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作者 张云龙 吴巧婉 +7 位作者 胡伟华 汪帆 邵韦涵 张诚明 赵忠波 何辉 樊启学 顾泽茂 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期757-762,共6页
The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach, Paramisgurnus dabryanus(Dabry de Thiersant, 1872), were determined from hatching to 60 days after hatching. A best power ... The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach, Paramisgurnus dabryanus(Dabry de Thiersant, 1872), were determined from hatching to 60 days after hatching. A best power model was estimated for the length-weight relationship during the early life stages. Positive allometric growth for the head segment, trunk length, tail length and eye diameter was also found in the early life stages, while body depth, tail depth, tail fi n length, pectoral fi n length and barbel length displayed a negative coeffi cient. During the subsequent early developmental stage, the growth coeffi cients showed a clear and common tendency towards isometry for all measured body ratios. The allometric growth changes in Chinese loach during the early stage are possibly the result of selective organogenesis directed towards survival priorities. 展开更多
关键词 Paramisgurnus dabryanus early life stages length-weight relationship allometric growth
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THE CONFIDENCE EVALUATION FOR AIRBORNE GPS DATA 被引量:1
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作者 LIU Jiyu CHEN Xiaoming 《Geo-Spatial Information Science》 2000年第1期50-56,共7页
GPS kinematic carrier phase measurements can be used to determine seven di- mension state and three attitude parameters of a motional carrier,such as an aircraft or a low- earth-orbit spacecraft,on which an antenna is... GPS kinematic carrier phase measurements can be used to determine seven di- mension state and three attitude parameters of a motional carrier,such as an aircraft or a low- earth-orbit spacecraft,on which an antenna is installed to receive GPS signals. It is known from airborne GPS test results for photogrammetry in China since 1994 that GPS carrier phase measurements in a motional environment have acquired external accuracies of ± 7. 9cm for two dimensional positions and ± 18. 1cm for point heights. This paper describes airborne GPS carrier phase -measurements with multireference stations and discusses how to evaluate the confidence of GPS kinematic data. 展开更多
关键词 airborne GPS receiver GPS kinematic carrier phase measurement multireferene ground station
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Evaluation of solvent-mediated phase transformation of glycine using oleic acid: Morphology and characterization study 被引量:1
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作者 Sevgi Polat Perviz Sayan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1829-1836,共8页
The polymorphic phase transformation of β-glycine to α-glycine was carried out both in the absence and presence of various concentrations of oleic acid used as additive at 25 ℃ in a water/ethanol medium. The effect... The polymorphic phase transformation of β-glycine to α-glycine was carried out both in the absence and presence of various concentrations of oleic acid used as additive at 25 ℃ in a water/ethanol medium. The effects of oleic acid and its concentration on phase transformation time were determined by continuously measuring the ultrasonic velocity. The crystals obtained by the completion of the phase transformation were characterized by XRD, SEM, and TG/DTG. The XRD and SEM results indicated that oleic acid significantly impacted phase transformation time and the morphological characteristics of the crystals. In addition to SEM analysis, detailed crystal shape analysis was performed and the circularity, elongation, and convexity parameters were determined quantitatively. TG/DTG analyses were performed to investigate thermal decomposition behavior and to calculate the activation energies based on different kinetic models such as FWO, KAS, Starink, and Tang kinetic models. With the addition of oleic acid to the medium, the calculated activation energy values increased from 89.63–90.63 to153.8–155.4 kJ·mol^(-1). The activation energy values showed that oleic acid was adsorbed on the crystal surface;this result was supported by FTIR, elemental, and Kjeldahl analyses. 展开更多
关键词 GLYCINE Oleic acid CRYSTALLIZATION Isoconversional methods Phase transformation
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Transformation of microstructure and phase of disodium guanosine 5′-monophosphate: Thermodynamic perspectives 被引量:1
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作者 Qiao Chen Fengxia Zou +4 位作者 Pengpeng Yang Jingwei Zhou Jinglan Wu Wei Zhuang Hanjie Ying 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2112-2120,共9页
Microstructure and phase transformation of disodium guanosine 5′-monophosphate(5′-GMPNa_2) are extremely important for controlling the process and understanding the mechanism of crystallization. In this work, the th... Microstructure and phase transformation of disodium guanosine 5′-monophosphate(5′-GMPNa_2) are extremely important for controlling the process and understanding the mechanism of crystallization. In this work, the thermodynamic properties of polymorphous 5′-GMPNa_2 especially the solubility were studied, the solubility results show that 5′-GMPNa_2 is more soluble in ethanol–water(E–W) than in isopropanol–water(I–W). The amorphous form of 5′-GMPNa_2 is more soluble than the crystalline form at the same mole fraction and temperature. Meanwhile, the crystalline forms and morphologies of the residual solids were characterized by PXRD and SEM. The results indicate that solid forms of 5′-GMPNa_2 transformed spontaneously from amorphous to crystalline when the ethanol proportion is ≥20%. In addition, increasing the pH facilitates the dissolution of 5′-GMPNa_2 and helps to maintain the crystalline form. The associated Gibbs free energy values were calculated to verify the trend of transformation from amorphous to crystalline 5′-GMPNa_2. These results should help to guide the industrial crystallization process and to obtain the crystalline form of 5′-GMPNa_2. 展开更多
关键词 Solid form transformation THERMODYNAMICS Disodium guanosine 5′-monophosphate SOLUBILITY CRYSTALLIZATION Intermolecular force
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Oncologic outcomes of primary and post-irradiated early stage rectal cancer: A retrospective cohort study 被引量:6
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作者 Chang—ZhengDu Yong—ChunChen +2 位作者 YongCai Wei—ChengXue. JinGU 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第27期3229-3234,共6页
AIM: To evaluate the oncologic outcomes of primary and post-irradiated early stage rectal cancer and the effectiveness of adjuvant chemotherapy for rectal cancer patients. METHODS: Eighty-four patients with stage Ⅰ r... AIM: To evaluate the oncologic outcomes of primary and post-irradiated early stage rectal cancer and the effectiveness of adjuvant chemotherapy for rectal cancer patients. METHODS: Eighty-four patients with stage Ⅰ rectal cancer after radical surgery were studied retrospectively and divided into ypstage Ⅰ group (n = 45) and pstage Ⅰ group (n = 39), according to their preoperative radiation, and compared by univariate and multivariate analysis. RESULTS: The median follow-up time of patients was 70 mo. No significant difference was observed in diseaseprogression between the two groups. The 5-year disease-free survival rate was 84.4% and 92.3%, respectively (P = 0.327) and the 5-year overall survival rate was 88.9% and 92.3%, respectively, for the two groups (P = 0.692). The disease progression was not significantly associated with the pretreatment clinical stage in ypstage Ⅰ group. The 5-year disease progression rate was 10.5% and 19.2%, respectively, for the patients who received adjuvant chemotherapy and for those who rejected chemotherapy in the ypstage Ⅰ group (P = 0.681). CONCLUSION: The oncologic outcomes of primary and post-irradiated early stage rectal cancer are similar. Patients with ypstage Ⅰ rectal cancer may slightly benefit from adjuvant chemotherapy. 展开更多
关键词 Rectal cancer Neoadjuvant radiotherapy Total mesorectal excision
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A Comparative Assessment of Aerodynamic Models for Buffeting and Flutter of Long-Span Bridges 被引量:3
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作者 Igor Kavrakov Guido Morgenthal 《Engineering》 SCIE EI 2017年第6期823-838,共16页
Wind-induced vibrations commonly represent the leading criterion in the design of long-span bridges. The aerodynamic forces in bridge aerodynamics are mainly based on the quasi-steady and linear unsteady theory. This ... Wind-induced vibrations commonly represent the leading criterion in the design of long-span bridges. The aerodynamic forces in bridge aerodynamics are mainly based on the quasi-steady and linear unsteady theory. This paper aims to investigate different formulations of self-excited and buffeting forces in the time domain by comparing the dynamic response of a multi-span cable-stayed bridge during the critical erection condition. The bridge is selected to represent a typical reference object with a bluff con- crete box girder for large river crossings. The models are viewed from a perspective of model complexity, comparing the influence of the aerodynamic properties implied in the aerodynamic models, such as aerodynamic damping and stiffness, fluid memory in the buffeting and self-excited forces, aerodynamic nonlinearity, and aerodynamic coupling on the bridge response. The selected models are studied for a windspeed range that is typical for the construction stage for two levels of turbulence intensity. Furthermore, a simplified method for the computation of buffeting forces including the aerodynamic admittance is presented, in which rational approximation is avoided. The critical flutter velocities are also compared for the selected models under laminar flow. 展开更多
关键词 BUFFETING FlutterLong-span bridges Bridge aerodynamics Bridge aeroelasticity Erection stage
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TeachingmA Way of Implementing Statistical Methods for Ordinal Data to Researchers
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作者 Elisabeth Svensson 《Journal of Mathematics and System Science》 2012年第1期8-12,共5页
The use of questionnaires, rating scales and other kinds of ordered classifications is unlimited and interdisciplinary, so it can take long time before novel statistical methods presented in statistical journals reach... The use of questionnaires, rating scales and other kinds of ordered classifications is unlimited and interdisciplinary, so it can take long time before novel statistical methods presented in statistical journals reach researchers of applied sciences. Therefore. teaching is an effective way of introducing novel methods to researchers at an early stage. Assessments on scales produce ordinal data having rank-invariant properties only, which means that suitable statistical methods are non-parametric and often rank-based. These limited mathematical properties have been taken into account in the research regarding development of statistical methods for paired ordinal data. The aim is to present a statistical method for paired ordinal data that has been successfully implemented to researchers from various disciplines together with statisticians attending interactive problem solving courses of biostatistics. 展开更多
关键词 Ordinal data rating scales RANKS reliability.
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How Many Packets Are Most Effective for Early Stage Traffic Identification: An Experimental Study 被引量:2
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作者 PENG Lizhi YANG Bo +1 位作者 CHEN Yuehui WU Tong 《China Communications》 SCIE CSCD 2014年第9期183-193,共11页
Accurately identifying network traffics at the early stage is very important for the application of traffic identification.Recent years,more and more research works have tried to build effective machine learning model... Accurately identifying network traffics at the early stage is very important for the application of traffic identification.Recent years,more and more research works have tried to build effective machine learning models to identify traffics with the few packets at the early stage.However,a basic and important problem is still unresolved,that is how many packets are most effective in early stage traffic identification.In this paper,we try to resolve this problem using experimental methods.We firstly extract the packet size of the first 2-10 packets of 3 traffic data sets.And then execute crossover identification experiments with different numbers of packets using 11 well-known machine learning classifiers.Finally,statistical tests are applied to find out which number is the best performed one.Our experimental results show that 5-7are the best packet numbers for early stage traffic identification. 展开更多
关键词 feature extraction early stagetraffic classification machine learning
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Edmund Becher Wilson's Early Contributions to the Chromosome Theory of Heredity: A Case Study of Instrumentalism in Science
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作者 Lilian Al-Chueyr Pereira Martins 《Journal of Philosophy Study》 2015年第9期431-443,共13页
The chromosome theory of inheritance was established during the three first decades of the 20th century. During the early stage of its substantiating, there were lots of puzzles and little evidence that could validate... The chromosome theory of inheritance was established during the three first decades of the 20th century. During the early stage of its substantiating, there were lots of puzzles and little evidence that could validate it. The cytological processes were obscure and several scientists maintained serious doubts concerning the existence of a connection between Mendel's principles and the behaviour of chromosomes during cell division. It was vital to associate an external, observable characteristic of the organism to a specific chromosome, and this was achieved when sex was connected to special chromosomes. At that time, however, some important scholars refused to accept or delayed acceptance of the conception that the hereditary factors (later called genes) were physical entities located along the chromosomes. Such was the case of Thomas Morgan (1866-1945) and William Bateson (186 I- 1926). Their attitudes could be explained by considering the doubtful ground of the hypothesis at that time. It is more difficult, however, to understand the attitude of Edmund Beecher Wilson (1856-1939). Being an expert in cytology he was acquainted with all the difficulties concerning the chromosome hypothesis. Nonetheless, from 1905 onward, he attributed little weight to the problems and dedicated a notable effort to obtaining evidence that could have grounded it. This paper analyses Wilson's attitude focusing on his studies from 1900 to 1915 and the scientific context of this period. This study led to the conclusion that Wilson's attitude could be explained in methodological terms by the adoption of an instrumentalist attitude, while Bateson and Morgan adopted a realistic perspective. 展开更多
关键词 history of genetics philosophy of biology chromosome hypothesis/theory WILSON Edmund Beecher INSTRUMENTALISM
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Big Data for Precision Medicine 被引量:8
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作者 Daniel Richard Leff Guang-Zhong Yang 《Engineering》 SCIE EI 2015年第3期277-279,共3页
This article focuses on the potential impact of big data analysis to improve health, prevent and detect disease at an earlier stage, and personalize interventions. The role that big data analytics may have in interrog... This article focuses on the potential impact of big data analysis to improve health, prevent and detect disease at an earlier stage, and personalize interventions. The role that big data analytics may have in interrogating the patient electronic health record toward improved clinical decision support is discussed. Weexamine developments in pharmacogenetics that have increased our appreciation of the reasons why patients respond differently to chemotherapy. We also assess the expansion of online health communications and the way in which this data may be capitalized on in order to detect public health threats and control or contain epidemics. Finally, we describe how a new generation of wearable and implantable body sensors may improve wellbeing, streamline management of chronic diseases, and improve the quality of surgical implants. 展开更多
关键词 big data biosensors body-sensing networks implantable sensors clinical decision support systems PHARMACOGENETICS MHEALTH
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Charles Sheeler's Paragone: Literary Influence and the Shaping of a Hierarchy
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作者 Heather L. Stark 《Journal of Literature and Art Studies》 2016年第3期226-234,共9页
This study is concerned with the literary and aesthetic influences that led to Charles Sheeler's formation of a paragone in his early 20th century work. This painter, photographer, printmaker, and experimental filmma... This study is concerned with the literary and aesthetic influences that led to Charles Sheeler's formation of a paragone in his early 20th century work. This painter, photographer, printmaker, and experimental filmmaker had very specific ideas concerning the hierarchy of the visual arts. While he is known for embracing a wide range of media and materials, by 1919 his aesthetic thought reveals a desire to elevate the painting over all other media. This formation of a visual paragone was initially influenced by his involvement in the interdisciplinary circles which surrounded both Alfred Stieglitz and Walter and Louise Arensberg in New York City. In particular, his lifelong friendship with the poet and writer William Carlos Williams would shape his aesthetic thought leading to his elevation of painting over all other media. Sheeler's paragone would begin to form during his stays at the rural Doylestown House in Bucks County, Pennsylvania. This rural home, which he first rented with fellow painter Morton Schamberg in 1916, would become an artistic refuge for both artists. While commercial photography was beginning to take up more if his time in Philadelphia, it was the retreats to the Doylestown house that enabled Sheeler to continue experiments in painting and begin to think of the photograph as something other than a document of architectural work. At this early stage in his artistic career, Sheeler was beginning to form his own hierarchy and contribute to the continuing argument of painting versus photography. 展开更多
关键词 AESTHETICS early 20th century American art interdisciplinarity LOCALISM
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Energy of Long-Lifetime Configurations in Zero-Temperature Dynamics
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作者 RONG Yong-Hui KONG Xiang-Mu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期671-674,共4页
Using Monte Carlo method with zero-temperature dynamics, we investigate energy evolution of Ising spin configuration on a square lattice. The energies of some configurations exhibit long duration before those configur... Using Monte Carlo method with zero-temperature dynamics, we investigate energy evolution of Ising spin configuration on a square lattice. The energies of some configurations exhibit long duration before those configurations reach the final state -- ground state or frozen stripe state. For ground-state dynamical realization, the duration occurs when the energy per spin is 4/L, where L is the lattice size. For stripe-state dynamical realization, the energy is slightly higher than 2/L when the duration appears in the last evolution stage. In addition, it is found that the average energy per spin in final state is approximately 2/3L. 展开更多
关键词 Ising model zero-temperature dynamics Monte Carlo method
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Cytochemical characterization of yolk granule acid phosphatase during early development of the oyster Crassostrea gigas(Thunberg)
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作者 王宜艳 孙虎山 +2 位作者 王艳杰 闫冬春 王磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期339-346,共8页
In this study, a cytochemical method and transmission electron microscopy was used to examine acid phosphatase activities of yolk granules throughout the early developmental stages of the Pacific oyster Crassostrea gi... In this study, a cytochemical method and transmission electron microscopy was used to examine acid phosphatase activities of yolk granules throughout the early developmental stages of the Pacific oyster Crassostrea gigas. This study aimed to investigate the dynamic change of yolk granule acid phosphatase, and the mechanisms underlying its involvement in yolk degradation during the early developmental stages of molluscs. Three types of yolk granules (YGI, YGⅡ, and YGⅢ) that differed in electron density and acid phosphatase reaction were identified in early cleavage, morula, blastula, gastrula, trochophore, and veliger stages. The morphological heterogeneities of the yolk granules were related to acid phosphatase activity and degrees of yolk degradation, indicating the association of acid phosphatase with yolk degradation in embryos and larvae of molluscs. Fusion of yolk granules was observed during embryogenesis and larval development of C. gigas. The fusion of YGI (free of acid phosphatase reaction) with YGII (rich in acid phosphatase reaction) could be the way by which yolk degradation is triggered. 展开更多
关键词 CYTOCHEMISTRY EGGS embryo larvae molluscs Pacific oyster yolk granules
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Effect of Ripening Stages on Basic Deep-Fat Frying Qualities of Plantain Chips
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作者 Ogan Mba Jamshid Rahimi Michael Ngadi 《Journal of Agricultural Science and Technology(A)》 2013年第5期341-348,共8页
Plantains (Musa paradisiaca L.) are a major food staple in West Africa and are cooked in various forms. The objective of this work was to evaluate the frying characteristics of plantains at different stages of ripen... Plantains (Musa paradisiaca L.) are a major food staple in West Africa and are cooked in various forms. The objective of this work was to evaluate the frying characteristics of plantains at different stages of ripening. The plantains used in the study were at the unripe stage through four different ripening stages. The samples were peeled and sliced into 2 mm thickness and blanched in hot water at 70 ℃ for 3 min. The slices were then deep flied in canola oil at 180 ℃. The result showed that ripening stage significantly affected moisture loss and fat absorption profiles of the plantain chips. Fully ripened plantain absorbed up to 34% (db) oil during 4 min frying, much higher than unripe plantain. The oil uptake and moisture loss during frying of the plantain chip samples were modelled using 1st order kinetics. The kinetic parameters including rates of moisture loss and oil uptake varied according to the different stages of ripening. Ripening had a significant effect on the colour lightness (L) of the chips. Similarly, the redness (a), the yellowness (b) and textural characteristics were significantly affected by ripening stage. 展开更多
关键词 Plantain ripening plantain chips DEEP-FRYING oil uptake moisture loss kinetics.
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CYTOLOGICAL COMPARISON OF GAMETOGENESIS OF SCALLOPS,ARGOPECTEN IRRADIANS AND CHLAMYS FARRERI
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作者 董新红 刘保忠 +1 位作者 吴长功 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期244-247,共4页
Histological characteristics of gametogenesis of two kinds of scallops, gonochoric Chinese scallop, Chlamys farreri and hermaphroditic bay scallop, Argopecten irradians were investigated in this study. Spermatogenesis... Histological characteristics of gametogenesis of two kinds of scallops, gonochoric Chinese scallop, Chlamys farreri and hermaphroditic bay scallop, Argopecten irradians were investigated in this study. Spermatogenesis in C. farreri has different developmental stages: spermatogonia, primary spermatocyte, second spermatocyte, spermatid and spermatozoon. A large number of same developmental stage spermatic cells converge at a definite area of the testis. Premeiotic, previtellogenic and vitellogenic oocytes can be found during oogenesis in C. farreri , where oocyte distribution is obviously irregular. The A. irradians gonad consists of two different parts in one individual: one part functions as testis, the other as ovary. Between these two parts is a special appearance area, where a large number of spermatic cells are bound with two layers of acellular substance with many oocytes in it. 展开更多
关键词 GAMETOGENESIS Argopecten irradians Chlamys farreri
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The Puritan Culture and Entrepreneurial Education Idea in American Universities
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作者 Zhang Suying Hu Weixia Lu Liping Fan Yulian 《International Journal of Technology Management》 2014年第2期73-75,共3页
The USA is one of the very developed countries with entrepreneurship education in colleges and universities.After more than half a century of development,it has reached a mature stage,and the formation of the concept ... The USA is one of the very developed countries with entrepreneurship education in colleges and universities.After more than half a century of development,it has reached a mature stage,and the formation of the concept of entrepreneurial education has advanced.In this paper, through the analysis of entrepreneurship education thought by Jeffrey Timmons as the representative of the America University entrepreneurship education idea, it finds out the Puritan culture factors,in order to better understand the basis and provides the reference of college enterprise education in China. 展开更多
关键词 the USA concept of entrepreneurship education in colleges and universities the Puritan culture
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