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EFFECT OF HEAVY DOPING ON THE OPTICAL SPECTRA OF SILICON

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Chinese Physics Letters 1985年第7期2卷 317-320页

作者： CHEN Chen-jia A.Borghesi G.Guizzetti L.Nosenzo E.Reguzzoni a.stella Department of Physics Peking UniversityBeijing Dipartmento di Fisica"A.Volta"dell University-27100 Pavia Italy

In this paper reflectance(R)and thermoreflectance(TR)spectra in heavily doped silicon concerning both interband and intraband transitions are reported and *** heavily doped sample shows a red-shift and lifetime broadening in the two singularrities E_(1)(~3.4eV)and E_(2)(~4.5eV).The values of the scattering timeτextracted from the reflectivity fit are obtained and compared with those obtained from Hall mobility measurements.

关键词： scattering reflectance lifetime

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掺硼多晶硅的远红外光谱

红外研究 1989年第5期8卷 321-326页

作者：陈辰嘉 A.Borghesi M.Geddo a.stella 北京大学物理系 Pavia大学物理系

用傅里叶变换光谱仪在15K和230～620cm^(-1)范围内研究了不同含Fe量的P型掺B多晶硅的远红外吸收光谱.观测和分析了Si中受主(B)基态到P_(3/2)价带相关的激发态系列的跃迁.实验结果表明,随着Fe浓度的增加,B受主激发谱的吸收强度显著减弱.... 详细信息

用傅里叶变换光谱仪在15K和230～620cm^(-1)范围内研究了不同含Fe量的P型掺B多晶硅的远红外吸收光谱.观测和分析了Si中受主(B)基态到P_(3/2)价带相关的激发态系列的跃迁.实验结果表明,随着Fe浓度的增加,B受主激发谱的吸收强度显著减弱.证明Fe-B对的形成和Fe杂质在晶粒边界的可能的积累.实验还观测到P型Si(B)中不同含Fe量时607cm^(-1)处C局域振动模的吸收变化,讨论了Fe杂质对C振动吸收的影响.

关键词：多晶硅远红外光谱硼

Phosphorus release from vivianite and hydroxyapatite by organic and inorganic compounds

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Pedosphere 2020年第2期30卷 190-200页

作者： stella GYPSER Dirk FREESE Brandenburg University of Technology Cottbus-Senftenberg Faculty of EnvironmentProcess EngineeringBiotechnology and ChemistryDepartment of Soil Protection and RecultivationKonrad-Wachsmann-Allee 6Cottbus 03046Germany

Based on recent mining rates and the exhaustion of global phosphorus(P)reserves,there is a need to mobilize P already stored in soils,and its recovery from secondary resources such as Ca-and Fe-phosphates is *** Ca-phosphate hydroxyapatite forms a good fertilizer source,while vivianite is formed in waterlogged soils and *** sludge treatment,the formation of vivianite has been identified,being mainly ***-term P release from both hydroxyapatite and vivianite was studied using different inorganic(CaCl2 and CaSO4)and organic(citric and humic acid)reagents during batch *** CaCl2 and CaSO4 represent the soil solution,while citric and humic acids as organic constituents affect P availability in the rhizosphere and during the process of ***,the flow-through reactor(FTR)technique with an infinite sink was used to study the long-term P release *** cumulative P release was higher by organic acids than by inorganic *** cumulative P release rates were higher in the FTR with CaCl2 as compared to the batch *** infinite sink application caused a continuously high concentration gradient between the solid and liquid phases,leading to higher desorption rates as compared to the batch *** predominant amount of the total P released over time was available for a short *** inorganic anion exchange occurred at easily available binding sites,organic acids affected the more heavily available binding sites,which could be embedded within the mineral *** results showed that organic compounds,especially citric acid,play a superior role as compared to the inorganic constituents of the soil solution during the recovery of already stored P from the tertiary phosphates vivianite and hydroxyapatite.

关键词： anion exchange batch technique citric acid flow-through reactor humic acid ligand exchange phosphate phosphorus recovery

Clinical implications of microRNAs in liver cancer stem cells

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Chinese Journal of Cancer 2013年第8期32卷 419-426页

作者： stella Chai Stephanie Ma Department of Clinical Oncology Li Ka Shing Faculty of Medicine The University of Hong Kong State Key Laboratory for Liver Research Li Ka Shing Faculty of Medicine The University of Hong Kong

The prognosis of patients diagnosed with hepatocellular carcinoma (HCC) is often dismal, mainly due to late presentation, high recurrence rate, and frequent resistance to chemotherapy and radiotherapy. Accumulating evidence on the differential microRNA (miRNA) expression patterns between non-tumor and HCC tissues or between liver cancer stem cells (CSCs) and non-CSC subsets and the significant clinical implications of these differences suggest that miRNAs are a promising, non-invasive marker for the prognosis and diagnosis of the disease. This perspective article summarizes the current knowledge of miRNAs in liver CSCs and highlights the need for further investigations of the role of miRNAs in regulating liver CSC subsets for possible future clinical applications.

关键词：肝干细胞 microRNA 临床意义肝癌 miRNAs 肝细胞癌表达模式小RNA

Social transformations of cultural heritage: from benefaction to sponsoring: Evidence from mountain regions in Greece

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Journal of Mountain Science 2020年第6期17卷 1475-1490页

作者： stella GIANNAKOPOULOU Dimitris KALIAMP AKOS Department of Rural and Surveying Engineering Aristotle University of Thessaloniki(AUTH)University Campus54124ThessalonikiGreece School of Mining and Metallurgical Engineering National Technical University of Athens(NTUA)9 Heroon Polytechnioustr.15780ZografouAthensGreece

The concept of benefaction,as shaped in the pre-industrial society,has been altered and replaced by the modern term of *** verbal transformation emerges from a deep cultural *** on the dipole of benefactionsponsoring,we examine the cultural transition from the traditional communities of long duration to the modern societies of consumption,taking the Greek mountainous regions as an *** investigate the cultural shift that generates the metastasis from the communities of benefaction to the modern brandplaces that consume their own cultural heritage,mainly,at the altar of the tourism *** society has adopted the concept of sponsoring,for the grace of which,culture has to prove evidence of economic value,in order to *** the extremely competitive frame of the free-market economy,mountain regions appear *** selling and buying of their culture are tempting and attractive under a constantly shrinking welfare-state and narrowing development *** depends on local and national society to rediscover and regenerate those social mechanisms able to create culture or let the modern consumption-oriented forces ***,authentic principles of benefaction may form an alternative perspective for social reorganization.

关键词： Benefaction Sponsoring Cultural heritage Mountain regions Place branding Place identity

Epigenetics of human melanoma： promises and challenges

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Journal of Molecular Cell Biology 2014年第5期8卷 356-367页

作者： Ahmad Besaratinia.stella Tommasi Department of Preventive Medicine Keck School of Medicine University of Southern California M/C 9603 Los Angeles CA 90033 USA

Melanoma is the deadliest form of skin cancer with rising incidence and mortality rates. Although early-stage melanoma is highly curable, advanced-stage melanoma is refractory to treatment. This underscores the importance of prevention and early detection as well as the need to improve treatment and prognostication of human melanoma. Elucidating the underlying mechanisms of the initi- ation and progression of human melanoma can help identify potential targets of intervention for prevention, diagnosis, therapy, and prognosis of this disease. Aberrant DNA methylation and histone modifications are the best-established epigenetic mechanisms of carcinogenesis. The occurrence of epigenetic changes prior to clinical diagnosis of cancer and their reversibility through pharmaco-logic/genetic approaches offer a promising avenue for basic and translational research on human melanoma. Candidate gene（s） or genome-wide aberrant DNA methylation and histone modifications have been observed in human melanoma tumor tissues and cell lines, and correlated to cellular and functional characteristics and/or clinicopathologicai features of this malignancy. The present review summarizes the published researches on aberrant DNA methylation and histone modifications in connection with human melanoma. Representative studies are highlighted to set forth the current state of knowledge, gaps in the knowledgebase, and future directions in these epigenetic fields of research. Examples of epigenetic therapy applied for human melanoma in vitro, and the challenges of its in vivo application for clinical treatment of solid tumors are discussed.

关键词： aberrant DNA methylation epigenetic therapy histone modifications melanoma cell lines skin cancer

Protection of architectural heritage: attitudes of local residents and visitors in Sirako, Greece

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Journal of Mountain Science 2016年第3期13卷 424-439页

作者： stella GIANNAKOPOULOU Dimitris KALIAMPAKOS School of Architectural Engineering National Technical University of AthensMetsovion Interdisciplinary Research Center School of Mining and Metallurgical Engineering National Technical University of Athens Metsovion Interdisciplinary Research Center

Architectural heritage comprises one o the most important elements of mountain settlements in Greece. It holds high cultural value, represents the tangible continuation of the past and forms the unique character and identity of each mountain region. Yet, controversy regarding funding for its preservation often arises. In this paper, we used two Contingent Valuation surveys to estimate the socia benefit deriving from protecting the traditiona architecture in the mountainous village of Sirako and through it, to examine perceptions and attitudes o local residents and visitors. Research findings revealed a strong social will in favor of the good's protection followed by high percentages of positive willingness to pay(WTP). However, WTP is significantly higher among residents. Cultura heritage value, of the good, appears to prevail, along with the environmental one. However, both residents and visitors pointed out that local heritage, if wellpreserved, will boost tourism development. Residents appeared to better recognize the true level o architectural decay, expressed higher apprehension for its protection and were willing to pay higher amount of money. Tourists, on the other side expressed high satisfaction for their visit, appreciated the beauty and serenity emerging from local built and natural environment and spent several days visiting the surrounding area. The longer they stayed and gotfamiliar with the village, the more willing they were to contribute to local heritage's protection. Percentages reflecting indifference for protecting architecture were extremely low. Yet, they were higher among tourists. Traditional architecture is considered as public good; an opinion resulting in an important percentage of visitors stating that national government should provide the necessary funding. In addition, the architecture appears to hold a high level of topicality. Those descending from Sirako or emotionally connected to it, of both social groups,turned out to be more co

关键词： Architectural heritage Contingent valuation Mountains Cultural goods

Effects of nanopillars and surface coating on dynamic traction force

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Microsystems & Nanoengineering 2023年第1期9卷 177-190页

作者： Yijun Cheng stella W.Pang Department of Electrical Engineering City University of Hong KongKowloonHong KongChina Centre for Biosystems Neuroscienceand NanotechnologyCity University of Hong KongKowloonHong KongChina

The extracellular matrix serves as structural support for cells and provides biophysical and biochemical cues for cell ***,material,and surface energy can regulate cell migration ***,the responses of MC3T3-E1 cells,including migration speed,morphology,and spreading on various platform surfaces,were ***(PDMS)micropost sensing platforms with nanopillars,silicon oxide,and titanium oxide on top of the microposts were fabricated,and the dynamic cell traction force during migration was *** relationships between various platform surfaces,migration behaviors,and cell traction forces were *** with the flat PDMS surface,cells on silicon oxide and titanium oxide surfaces showed reduced mobility and less *** the other hand,cells on the nanopillar surface showed more elongation and a higher migration speed than cells on silicon oxide and titanium oxide ***3T3-E1 cells on microposts with nanopillars exerted a larger traction force than those on flat PDMS microposts and had more filopodia and long *** the relationships between platform surface condition,migration behavior,and cell traction force can potentially lead to better control of cell migration in biomaterials capable of promoting tissue repair and regeneration.

关键词： coating traction surface

Pavement sustainability index for highway infrastructures： A case study of Maryland

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 192-200页

作者： stella O. OBAZEE-IGBINEDION Oludare OWOLABI Montgomery County Department of Transportation 100 Edison Park Drive Gaithersburg MD 20878 USA Department of Civil Engineering Morgan State University 1700 East Cold Spring Lane Baltimore MD 21251 USA

Pavement deterioration creates conditions that undermine their performances, which gives rise to the need for maintenance and rehabilitation. This paper develops a mathematical multi-linear regression analysis （MLRA） model to determine a pavement sustainability index （PSTI） as dependent variable for flexible pavements in Maryland. Four categories of pavement performance evaluation indicators are subdivided into seven pavement condition indices and analyzed as independent variables for each section of pavement. Data are collected from five different roadways using field evaluations and existing database. Results indicate that coefficient of determination （R^2） is correlated and significant, R^2 = 0.959. Of the seven independent variables, present serviceability index （PSI） is the most significant with a coefficient value of 0.032, present serviceability rating （PSR） coefficient value=0.028, and international roughness index （IRI） coefficient value = -0.001. Increasing each unit value of coefficients for PSI and PSR would increase the value of PSTI; thereby providing a more sustainable pavement infrastructure; which explains the significance of the model and why IR/ will most likely impact environmental, economic and social values.

关键词： pavement indices sustainability pavement performance flexible pavements