175 resultados para EBL resists
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Open reading frames in the Plasmodium falciparum genome encode domains homologous to the adhesive domains of the P. falciparum EBA-175 erythrocyte-binding protein (eba-175 gene product) and those of the Plasmodium vivax and Plasmodium knowlesi Duffy antigen-binding proteins. These domains are referred to as Duffy binding-like (DBL), after the receptor that determines P. vivax invasion of Duffy blood group-positive human erythrocytes. Using oligonucleotide primers derived from short regions of conserved sequence, we have developed a reverse transcription-PCR method that amplifies sequences encoding the DBL domains of expressed genes. Products of these reverse transcription-PCR amplifications include sequences of single-copy genes (including eba-175) and variably transcribed genes that cross-hybridize to multiple regions of the genome. Restriction patterns of the multicopy genes show a high degree of polymorphism among different parasite lines, whereas single-copy genes are generally conserved. Characterization of the single-copy genes has identified a gene (ebl-1) that is related to eba-175 and is likely to be involved in erythrocyte invasion.
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In this work, new coordination polymers based on two different classes of synthons are presented. In addition, manganese-based metallacrowns of magnetic interest are studied, both in the solid state and in solution. Firstly, functionalized bispyrazolylmethane derivatives are employed as bridging ligands for the establishment of silver-based coordination polymers; the influence of the substituent groups and of the counterions on the supramolecular packing is also investigated. Secondly, the use of metallacrown (MC) complexes as building blocks for porous coordination polymers is discussed. The design of a new metallacrown species is presented, which shows the tendency of aggregating in the solid state to form coordination polymers. Two new coordination polymers are indeed reported, of which one is the first MC-based permanently porous coordination network ever presented. The solid resists solvent evacuation and exhibits gas uptake ability. Furthermore, the isolation and characterization of a new metallacryptate species based on manganese ions is described. The metal-rich structure comprises nine Mn(II)/Mn(III) ions and presents an inverse metallacrown core subunit that binds a μ3-O2- ion. The metallacryptate is isolated in high yields and stable in solution. Lastly, a family of 3d-4f heterometallic metallacrowns is characterized in solution by means of UV-Vis spectrophotometry and of paramagnetically shifted 1H-NMR. The lanthanide-induced shifts observed in the spectra are employed to describe the molecules behaviour in solution and are qualitatively related to the magnetic properties of the compounds.
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This study examines worldwide usage of over 600,000 e-books from Ebook Library (EBL) and ebrary. Using multiple modes of analysis, the study shows that there are variations in usage by geographic region as well as by subject. The study examines usage in relation to availability of titles, different types of usage per session, usage of the top ten percent of titles, and intensive and extensive use. These patterns can be used for benchmarking and as a model for local e-book studies.
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A Justificação pela Fé no contexto da Reforma protestante do século XVI apresentou-se como um enunciado libertador das práticas pastorais meritórias. Ressignificou conceitos teológicos. Apontou para uma nova forma de vida cristã tendo a salvação como seu princípio, não seu objetivo. Formatou, desta forma, o fundamento de um modo de vida: o modo justificado de viver. Um modo que define a integralidade do ser. Modo que, dogmatizado com o passar dos anos, impôs-se como doutrina em detrimento da vivência. Esta pesquisa se propõe a apontar para a relevância da Justificação pela Fé no contexto do século XVI, assinalar aspectos que fundamentam e moldam o novo modo de vida da pessoa justificada pela fé e afirma a Justificação pela Fé como o fundamento de um modo de vida resistente ao sistema hegemônico da sociedade de mercado do século XXI.
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We report the control of surface relief grating parameters and roughness for phase masks produced using e-beam lithography (EBL) and reactive ion etching (RIE). The relationships between processing conditions, grating parameters, surface roughness and the diffraction efficiency of the zeroth and the two first order transmitted beams are discussed.
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This article describes the process through which the subjectivity of the illegal immigrant is deconstructed and later reconstructed, as revealed by the Moroccan journalist and intellectual Rachid Nini in his book Diario de un ilegal/Diary of an Illegal Immigrant (2002), an account of the author's perils as an illegal immigrant in Spain. The analysis focuses firstly on the narrative form that Nini employs to give an account of his story, and secondly on the spatial displacement to which the subject and his subjectivity are exposed, which leads to the obliteration of his identity. The abrupt changes that the subject faces in a new location are paramount and impel him to a constant quest for self-definition and of negotiation with the new Other. Thus, the privileges that Nini enjoyed while in Morocco, those of a male journalist, poet, translator and intellectual with a university degree, disappear altogether once his plane has landed on the Canary Islands. In this new location, the place of origin and/or race are now what define his identity; he is now simply a moro - a Moor - he is not considered as an individual but, as will be shown, as a member of a homogenizing category which resists definition. The article finishes by addressing how Nini, in his quest to destroy homogenizing stereotypes, employs other stereotypes as though this were the only escape from the schizophrenic state the illegal immigrant identity had been forced into.
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Purpose – This paper aims to focus on developing critical understanding in human resource management (HRM) students in Aston Business School, UK. The paper reveals that innovative teaching methods encourage deep approaches to study, an indicator of students reaching their own understanding of material and ideas. This improves student employability and satisfies employer need. Design/methodology/approach – Student response to two second year business modules, matched for high student approval rating, was collected through focus group discussion. One module was taught using EBL and the story method, whilst the other used traditional teaching methods. Transcripts were analysed and compared using the structure of the ASSIST measure. Findings – Critical understanding and transformative learning can be developed through the innovative teaching methods of enquiry-based learning (EBL) and the story method. Research limitations/implications – The limitation is that this is a single case study comparing and contrasting two business modules. The implication is that the study should be replicated and developed in different learning settings, so that there are multiple data sets to confirm the research finding. Practical implications – Future curriculum development, especially in terms of HE, still needs to encourage students and lecturers to understand more about the nature of knowledge and how to learn. The application of EBL and the story method is described in a module case study – “Strategy for Future Leaders”. Originality/value – This is a systematic and comparative study to improve understanding of how students and lecturers learn and of the context in which the learning takes place.
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Despite the large body of research regarding the role of memory in OCD, the results are described as mixed at best (Hermans et al., 2008). For example, inconsistent findings have been reported with respect to basic capacity, intact verbal, and generally affected visuospatial memory. We suggest that this is due to the traditional pursuit of OCD memory impairment as one of the general capacity and/or domain specificity (visuospatial vs. verbal). In contrast, we conclude from our experiments (i.e., Harkin & Kessler, 2009, 2011; Harkin, Rutherford, & Kessler, 2011) and recent literature (e.g., Greisberg & McKay, 2003) that OCD memory impairment is secondary to executive dysfunction, and more specifically we identify three common factors (EBL: Executive-functioning efficiency, Binding complexity, and memory Load) that we generalize to 58 experimental findings from 46 OCD memory studies. As a result we explain otherwise inconsistent research – e.g., intact vs. deficient verbal memory – that are difficult to reconcile within a capacity or domain specific perspective. We conclude by discussing the relationship between our account and others', which in most cases is complementary rather than contradictory.
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We report the control of surface relief grating parameters and roughness for phase masks produced using e-beam lithography (EBL) and reactive ion etching (RIE). The relationships between processing conditions, grating parameters, surface roughness and the diffraction efficiency of the zeroth and the two first order transmitted beams are discussed.
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Relevant carbon-based materials, home-made carbon-silica hybrids, commercial activated carbon, and nanostructured multi-walled carbon nanotubes (MWCNT) were tested in the oxidative dehydrogenation of ethylbenzene (EB). Special attention was given to the reaction conditions, using a relatively concentrated EB feed (10 vol.% EB), and limited excess of O2 (O 2:EB = 0.6) in order to work at full oxygen conversion and consequently avoid O2 in the downstream processing and recycle streams. The temperature was varied between 425 and 475 °C, that is about 150-200 °C lower than that of the commercial steam dehydrogenation process. The stability was evaluated from runs of 60 h time on stream. Under the applied reactions conditions, all the carbon-based materials are apparently stable in the first 15 h time on stream. The effect of the gasification/burning was significantly visible only after this period where most of them fully decomposes. The carbon of the hybrids decomposes completely rendering the silica matrix and the activated carbon bed is fully consumed. Nano structured MWCNT is the most stable; the structure resists the demanding reaction conditions showing an EB conversion of ∼30% (but deactivating) with a steady selectivity of ∼80%. The catalyst stability under the ODH reaction conditions is predicted from the combustion apparent activation energies. © 2014 Elsevier Ltd. All rights reserved.
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A mild protocol that allows the template removal of soft un-aged silica nanoparticles was investigated. After oxidizing the organic template by Fenton chemistry, a good structural preservation is only achieved when the material is equilibrated and dried in a low-surface tension solvent. This avoids excessive capillary stress induced by the high surface tension of water, a major component in the Fenton reaction medium. The Fenton reaction should be carried out under mild conditions as well; otherwise the sample deteriorates by extensive hydrolysis, and capillary stress, and the structural ordering diminishes severely. We propose employing 10 ppm Fe concentration at 70 °C for 24 h for the cetyltrimethylammonium bromide template. The proposed protocol involves 2 steps resulting in an overall significantly higher pore volume attributed to the wider pores and limited particle agglomeration, while the calcined counterpart evidences aggregation and loss of the hexagonal ordering. n-BuOH exchange is unnecessary when the mesophase is stabilized by ageing, as the structure resists the water capillary stress. © The Royal Society of Chemistry 2013.
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Tanulmányunk célja a versenyképesség közösségi beágyazottságának elemzéséhez alkalmas elemzési keretek bemutatása és a versenyképesség fogalmának elemzése a fogalom intézményi, normatív tartalma szempontjából. Célunk a közösségi versenyképesség fogalmának és az ezt elemezni képes megközelítés kidolgozása. A feladat kettős: 1. A versenyképesség értelmezése a döntések közösségi keretei szempontjából 2. A közösségi keretek versenyképességre gyakorolt hatásának elemzése Ennek érdekében a tanulmány első fejezetében az egyéni döntést meghatározó tényezőket és az egyéni döntések jövőbeli interakciók környezetére gyakorolt hatását elemző keretet vázoljuk fel. Megközelítésünk szerint az egyéni döntést négy tényező határozza meg. a közösségi környezet, a természeti környezet, s személyes jellemzők és az interakciós partnerek. Az ez alapján születő döntések formálják a jövőbeli döntési környezetet. A döntések hatásának elemzéséhez a környezetre gyakorolt hatások értékelését orientáló fogalomra van szükség. Elemzésünk esetében ez a fogalom az értékteremtés, amit a következőképp határozunk meg: az értékteremtő tevékenységek során valaki arra törekszik, hogy saját személyes céljait a másokkal való kölcsönösen előnyös együttműködések lehetőségeinek bővítésével, hozamainak növelésével szolgálja. A második fejezetben az egyéni döntések közösségi kereteit és az egyéni döntések közösségre gyakorolt hatását elemezzük részletesen. A formális és informális intézmények világát, a közösségi magatartásokat szabályozó normák és konvenciók rendszerét a következő öt – a valóságban gyakran keveredő - alapelemre bontjuk értékrend, konvenció, közösségi szabály, hivatalos előírás, egyének közötti megállapodás. Ezek közül a magánszereplők együttműködésének az érintett szereplők által módosítható intézményi elemeinek (konvenció, megállapodás) alkalmazkodása a leggyorsabb, a közösség egészét irányító formális intézmények a status quo iránti elfogultságuk miatt lomhábbak, míg a közösség életét informálisan befolyásoló normák a legstabilabb intézményi elemek. A közösségek változása általában lassú, legtöbbször nem szándékolt hatások következménye. Mindezek mellett a közösségi intézmények tudatos alakításában komoly szerepe van (1) a konvenciókat megújító intézményi innovátoroknak, (2) a szerződéses formulákon módosító vállalkozóknak és (3) a hivatalos előírások formálásába bekapcsolódó politikai szereplőknek politikai vállalkozóként, tisztviselőként, vagy közéleti résztvevőként. A harmadik fejezetben a versenyképesség fogalmát elemezzük, és ez alapján határozzuk meg a közösségi versenyképesség fogalmát. Megvizsgáljuk, milyen feltevésekkel él a fogalom a közösségi környezettel kapcsolatban, illetve milyen normatív elemei vannak a definíciónak. A vizsgálathoz a versenyképesség fogalmának egy lecsupaszított változatát használtuk. E szerint a versenyképesség valaki képessége értékteremtő módon bekapcsolódni a gazdasági munkamegosztásba úgy, hogy tevékenysége relatív hozama nem csökken. Az elemzés alapján a versenyképesség a közösségi környezet következő hét elemére épül: 1. A közösség tagjainak és a tagság tartalmának meghatározottsága; 2. a potenciális együttműködő felek közös múltja, jövője, konvenció- és normarendszere; 3. A gazdasági együttműködés intézményeinek (csere, vállalkozás, tulajdon, szerződés) működőképessége; 4. Az értékteremtés normatív koncepciója és az arra épülő részleteiben meghatározott, és részleteiben is közösségi legitimációval bíró szabályrendszer; 5. Az innovációt támogató és a kellően rugalmas értékrend és közösségi szabályok. 6. A gazdasági munkamegosztás igényeihez részleteiben és változásával is igazodó konvenciók, hivatalos előírások és szerződések; 7. A közösségi környezet tudatos alakításával foglalkozó szereplők (közösségi innovátorok, vállalkozók és politikai szereplők) motivációja és lehetősége a hozamok relatív szintjének tartását támogató intézményi környezet karbantartásában. A versenyképesség fogalmának intézményi elemzése rámutat, hogy a fogalom gazdag értéktartalommal és határozott közösségi intézményrendszer-képpel rendelkezik. A közösségi versenyképesség ez alapján a versenyképesség fogalmába kódolt közösségi környezetként határozható meg. A kutatás következő lépése a közösségi versenyképesség meghatározása, az azt befolyásoló mechanizmusok feltárása és javítását támogató elemzési eszközök, gyakorlati segédletek kidolgozása. Ezen feladatok előkészítése érdekében a tanulmány mellékletében két történelmi esettanulmányt mutatunk be, röviden áttekintjük a téma szempontjából releváns irodalom főbb eredményeit és bemutatunk egy praktikus alkalmazásra szánt normatív elemzési eszközt, mellyel az elemezhető, hogy az állami lépések mennyire bátorítják az értékteremtő vállalkozást. _________ This paper (1) introduces an analytical framework to study the impact of the community on competitiveness and (2) analyses the institutional and normative content in the concept of competitiveness. The goal is to elaborate an approach that supports the definition and analysis of the ‘competiveness of community’. This task has two main parts: 1. interpretation of competiveness from social choice perspective 2. assessing the impact of social settings on the competiveness of a community The first chapter of the study draws up an analytical framework to study the social factors of individual decisions and their impact on the environment of future interactions. We focus on four main factors that shape setting of future interactions: social environment, natural environment, personal characteristics and partners in interactions. We use the concept of value creation to assess the impact of individual decisions on these factors. The second chapter discusses the social factors of individual decisions and the impact of individual decisions on the community. Institutions are conceptualized as value systems, conventions, community rules, official rules and contracts in the study. The conventions and contracts can accommodate to the changes of environment more smoothly, formal institutions are less flexible due to their bias toward status quo. Informal rules and value systems resists change more frequently. The formation of social environment is usually slow and based on unintended effects. Altogether (1) innovators who revise social conventions, (2) entrepreneurs who reshape contracts and (4) political entrepreneurs who formulate formal rules have influential roles on the institutional setting. The third chapter discusses the social assumptions included into the definition of competitiveness and we give a definition for the competiveness of communities. A simplified definition of competitiveness is used for this analysis: competiveness is someone’s ability and motivation to participate in the economic division of labor in a way that is based on value creation and maintains the relative return of activities. Our analysis reveals that competitiveness assumes the following features of the community: 1. Defined membership of community: who are the members and what does membership mean. 2. Common past, future, convention and norm system of the potential participants of interactions 3. Functionality of institutions that facilitate division of labor (exchange, entrepreneurship, property, contract) 4. Existing normative concept on value creation and social accepted rules that govern interactions 5. Value system and rules that promote innovation 6. Conventions, official norms and contracts that fits to economic division of labor in a detailed and dynamic way 7. Motivation and potential of actors who shape social environment consciously to maintain institutions in order to sustain the relative return of economic activities This analysis shows that the concept of competitiveness assumes well established values and detailed expectations on institutional settings. Followingly, competiveness of community can be defined with these criteria of social environment. Two historical case studies and the draft of a policy oriented toolkit demonstrate the applicability of the introduced approach in the appendix. The core findings of the literature are also reviewed there.
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Currently the data storage industry is facing huge challenges with respect to the conventional method of recording data known as longitudinal magnetic recording. This technology is fast approaching a fundamental physical limit, known as the superparamagnetic limit. A unique way of deferring the superparamagnetic limit incorporates the patterning of magnetic media. This method exploits the use of lithography tools to predetermine the areal density. Various nanofabrication schemes are employed to pattern the magnetic material are Focus Ion Beam (FIB), E-beam Lithography (EBL), UV-Optical Lithography (UVL), Self-assembled Media Synthesis and Nanoimprint Lithography (NIL). Although there are many challenges to manufacturing patterned media, the large potential gains offered in terms of areal density make it one of the most promising new technologies on the horizon for future hard disk drives. Thus, this dissertation contributes to the development of future alternative data storage devices and deferring the superparamagnetic limit by designing and characterizing patterned magnetic media using a novel nanoimprint replication process called "Step and Flash Imprint lithography". As opposed to hot embossing and other high temperature-low pressure processes, SFIL can be performed at low pressure and room temperature. Initial experiments carried out, consisted of process flow design for the patterned structures on sputtered Ni-Fe thin films. The main one being the defectivity analysis for the SFIL process conducted by fabricating and testing devices of varying feature sizes (50 nm to 1 μm) and inspecting them optically as well as testing them electrically. Once the SFIL process was optimized, a number of Ni-Fe coated wafers were imprinted with a template having the patterned topography. A minimum feature size of 40 nm was obtained with varying pitch (1:1, 1:1.5, 1:2, and 1:3). The Characterization steps involved extensive SEM study at each processing step as well as Atomic Force Microscopy (AFM) and Magnetic Force Microscopy (MFM) analysis.
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Germanium was of great interest in the 1950’s when it was used for the first transistor device. However, due to the water soluble and unstable oxide it was surpassed by silicon. Today, as device dimensions are shrinking the silicon oxide is no longer suitable due to gate leakage and other low-κ dielectrics such as Al2O3 and HfO2 are being used. Germanium (Ge) is a promising material to replace or integrate with silicon (Si) to continue the trend of Moore’s law. Germanium has better intrinsic mobilities than silicon and is also silicon fab compatible so it would be an ideal material choice to integrate into silicon-based technologies. The progression towards nanoelectronics requires a lot of in depth studies. Dynamic TEM studies allow observations of reactions to allow a better understanding of mechanisms and how an external stimulus may affect a material/structure. This thesis details in situ TEM experiments to investigate some essential processes for germanium nanowire (NW) integration into nanoelectronic devices; i.e. doping and Ohmic contact formation. Chapter 1 reviews recent advances in dynamic TEM studies on semiconductor (namely silicon and germanium) nanostructures. The areas included are nanowire/crystal growth, germanide/silicide formation, irradiation, electrical biasing, batteries and strain. Chapter 2 details the study of ion irradiation and the damage incurred in germanium nanowires. An experimental set-up is described to allow for concurrent observation in the TEM of a nanowire following sequential ion implantation steps. Grown nanowires were deposited on a FIB labelled SiN membrane grid which facilitated HRTEM imaging and facile navigation to a specific nanowire. Cross sections of irradiated nanowires were also performed to evaluate the damage across the nanowire diameter. Experiments were conducted at 30 kV and 5 kV ion energies to study the effect of beam energy on nanowires of varied diameters. The results on nanowires were also compared to the damage profile in bulk germanium with both 30 kV and 5 kV ion beam energies. Chapter 3 extends the work from chapter 2 whereby nanowires are annealed post ion irradiation. In situ thermal annealing experiments were conducted to observe the recrystallization of the nanowires. A method to promote solid phase epitaxial growth is investigated by irradiating only small areas of a nanowire to maintain a seed from which the epitaxial growth can initiate. It was also found that strain in the nanowire greatly effects defect formation and random nucleation and growth. To obtain full recovery of the crystal structure of a nanowire, a stable support which reduces strain in the nanowire is essential as well as containing a seed from which solid phase epitaxial growth can initiate. Chapter 4 details the study of nickel germanide formation in germanium nanostructures. Rows of EBL (electron beam lithography) defined Ni-capped germanium nanopillars were extracted in FIB cross sections and annealed in situ to observe the germanide formation. Chapter 5 summarizes the key conclusions of each chapter and discusses an outlook on the future of germanium nanowire studies to facilitate their future incorporation into nanodevices.
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Electron beam lithography (EBL) and focused ion beam (FIB) methods were developed in house to fabricate nanocrystalline nickel micro/nanopillars so to compare the effect of fabrication on plastic yielding. EBL was used to fabricate 3 μm and 5 μm thick poly-methyl methacrylate patterned substrates in which nickel pillars were grown by electroplating with height to diameter aspect ratios from 2:1 to 5:1. FIB milling was used to reduce larger grown pillars to sizes similar to EBL grown pillars. X-ray diffraction, electron back-scatter diffraction, scanning electron microscopy, and FIB imaging were used to characterize the nickel pillars. The measured grain size of the pillars was 91±23 nm, with strong <110> and weaker <111> and <110> crystallographic texture in the growth. Load-controlled compression tests were conducted using a MicroMaterials nano-indenter equipped with a 10 μm flat punch at constant rates from 0.0015 to 0.03 mN/s on EBL grown pillars, and 0.0015 and 0.015 mN/s on FIB-milled pillars. The measured Young’s modulus ranged from 55 to 350 GPa for all pillars, agreeing with values in the literature. EBL grown pillars exhibited stochastic strain-bursts at slow loading rates, attributed to local micro yield events, followed by work hardening. Sharp yield points were also observed and attributed to the gold seed layer de-bonding between the nickel pillar and substrate due to the shear stress associated with end effects that arise from the substrate constraint. The onset of yield ranged from 108 to 1800 MPa, which is greater than bulk nickel, but within values given in the literature. FIB-milled pillars demonstrated stochastic yield behaviour at all loading rates tested, yielding between 320 and 625 MPa. Deformation was apparent at FIB-milled pillar tops, where the smallest cross-sectional area was measured, but still exhibited superior yield strength to bulk nickel. The gallium damage at the outer surface of the pillars likely aids in dislocation nucleation and plasticity, leading to lower yield strengths than for the EBL pillars. Thermal drift, substrate effects, and noise due to vibrations within the indenter system contributed to variance and inconsistency in the data.