139 resultados para AK40-4324
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The adsorption of stearic acid on both sodium montmorillonites and calcium montmorillonites has been studied by near infrared spectroscopy complimented with infrared spectroscopy. Upon adsorption of stearic acid on Ca-Mt additional near infrared bands are observed at 8236 cm-1 and is assigned to an interaction of stearic acid with the water of hydration. Upon adsorption of the stearic acid on Na-Mt, the NIR bands are now observed at 5671, 5778, 5848 and 5912 cm-1 and are assigned to the overtone and combination bands of the CH fundamentals. Additional bands at 4177, 4250, 4324, 4337, 4689 and 4809 cm-1 are attributed to CH combination bands resulting from the adsorption of the stearic acid. Stearic acid is used as a model molecule for adsorption studies. The application of near infrared spectroscopy to the study of this adsorption proved most useful.
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This volume puts together the works of a group of distinguished scholars and active researchers in the field of media and communication studies to reflect upon the past, present, and future of new media research. The chapters examine the implications of new media technologies on everyday life, existing social institutions, and the society at large at various levels of analysis. Macro-level analyses of changing techno-social formation – such as discussions of the rise of surveillance society and the "fifth estate" – are combined with studies on concrete and specific new media phenomena, such as the rise of Pro-Am collaboration and "fan labor" online. In the process, prominent concepts in the field of new media studies, such as social capital, displacement, and convergence, are critically examined, while new theoretical perspectives are proposed and explicated. Reflecting the inter-disciplinary nature of the field of new media studies and communication research in general, the chapters interrogate into the problematic through a range of theoretical and methodological approaches. The book should offer students and researchers who are interested in the social impact of new media both critical reviews of the existing literature and inspirations for developing new research questions.
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This book explores the evolving political culture in Indonesia, by discussing the country's dominant political philosophies, then showing how those philosophies affect the working lives of ordinary Indonesian citizens. It focuses in particular on the working lives of news journalists, a group that occupies a strategic social and political position.
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This work reports the effect of seed nanoparticle size and concentration effects on heterogeneous crystal nucleation and growth in colloidal suspensions. We examined these effects in the Au nanoparticle-seeded growth of Au-ZnO hetero-nanocrystals under synthesis conditions that generate hexagonal, cone-shaped ZnO nanocrystals. It was observed that small (~ 4 nm) Au seed nanoparticles form one-to-one Au-ZnO hetero dimers and that Au nanoparticle seeds of this size can also act as crystallization ‘catalysts’ that readily promote the nucleation and growth of ZnO nanocrystals. Larger seed nanoparticles (~9 nm, ~ 11 nm) provided multiple, stable ZnO-nucleation sites, generating multi-crystalline hetero trimers, tetramers and oligomers.
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Stay-green sorghum plants exhibit greener leaves and stems during the grain-filling period under water-limited conditions compared with their senescent counterparts, resulting in increased grain yield, grain mass, and lodging resistance. Stay-green has been mapped to a number of key chromosomal regions, including Stg1, Stg2, Stg3, and Stg4, but the functions of these individual quantitative trait loci (QTLs) remain unclear. The objective of this study was to show how positive effects of Stg QTLs on grain yield under drought can be explained as emergent consequences of their effects on temporal and spatial water-use patterns that result from changes in leaf-area dynamics. A set of four Stg near-isogenic lines (NILs) and their recurrent parent were grown in a range of field and semicontrolled experiments in southeast Queensland, Australia. These studies showed that the four Stg QTLs regulate canopy size by: (1) reducing tillering via increased size of lower leaves, (2) constraining the size of the upper leaves; and (3) in some cases, decreasing the number of leaves per culm. In addition, they variously affect leaf anatomy and root growth. The multiple pathways by which Stg QTLs modulate canopy development can result in considerable developmental plasticity. The reduction in canopy size associated with Stg QTLs reduced pre-flowering water demand, thereby increasing water availability during grain filling and, ultimately, grain yield. The generic physiological mechanisms underlying the stay-green trait suggest that similar Stg QTLs could enhance post-anthesis drought adaptation in other major cereals such as maize, wheat, and rice.
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Arts education research, as an interdisciplinary field, has developed in the shadows of a number of research traditions. However amid all the methodological innovation, I believe there is one particular, distinctive and radical research strategy which arts educators have created to research the practice of arts education: namely arts-based research. For many, and Elliot Eisner from Stanford University was among the first, arts education needed a research approach which could deal with the complex dynamics of arts education in the classroom. What was needed was ‘an approach to the conduct of educational research that was rooted in the arts and that used aesthetically crafted forms to reveal aspects of practice that mattered educationally’ (Eisner 2006: 11). While arts education researchers were crafting the principles and practices of arts-based research, fellow artist/researchers in the creative arts were addressing similar needs and fashioning their own exacting research strategies. This chapter aligns arts-based research with the complementary research practices established in creative arts studios and identifies the shared and truly radical nature of these moves. Finally, and in a contemporary turn many will find surprising, I will discuss how the radical aspects of these methodologies are now being held up as core elements of what is being called the fourth paradigm of scientific research, known as eScience. Could it be that the radical dynamics of arts-based research pre-figured the needs of eScience researchers who are currently struggling to manage the ‘deluge of Big Data’ which is disrupting their well-established scientific methods?
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Uusi hermoston rappeumasairaus MIRAS: Suomessa kantajia joka 125. väestöstä Tässä väitöskirjatyössä on kuvattu uusi peittyvästi periytyvä hermoston rappeumasairaus, MIRAS (mitochondrial recessive ataxia syndrome), ja sen geenitausta. Tauti osoittautui tutkimuksessamme Suomen yleisimmäksi perinnölliseksi ataksiasairaudeksi. Tutkimuksessa on tutkittu perinnöllisiä aivosairauksia, joissa yhtenä oireena on ataksia (kävelyn epävarmuus, tasapainovaikeus ja liikkeiden haparointi), sekä lukuisia muita aivojen toimintahäiriöstä johtuvia oireita. Seuloessamme suomalaisilta ataksiapotilailta MIRAS-geenivirhettä, 27 potilasta sai diagnoosin aikaisemmin tuntemattomalle, etenevälle ataksiasairaudelleen. Tutkimuksen tuloksena kyseisen geenivirheen DNA-diagnostiikka on otettu käyttöön suomalaisissa ja eurooppalaisissa laboratorioissa, ja toista sataa potilasta ympäri maailman on saanut diagnoosin. Suomen väestössä joka 125. kantaa MIRAS geenivirhettä, mutta taudin saa vain, jos perii geenivirheen molemmilta vanhemmiltaan. MIRAS on taudinkuvaltaan vaihteleva, mutta vaikea etenevä neurologinen sairaus. Useilla potilailla esiintyvät oireet ovat ataksia, puheen puuromaisuus (dysartria), ääreishermorappeuma (neuropatia), pakkoliikkeet, psykiatriset oireet sekä vaikea epilepsia. Erityisen tärkeää MIRAS-taudin tunnistaminen on siihen liittyvän epilepsian hoitopäätöksessä: valproaatti-lääkitys voi aiheuttaa MIRAS-potilaille vaikean maksavaurion. Väitöskirjatyön tuloksena selvisi, että kaikki suomalaiset, norjalaiset, belgialaiset, englantilaiset, australialaiset ja uusi-seelantilaiset MIRAS potilaat olivat kaukaista sukua samalle, tuhansia vuosia sitten eläneelle eurooppalaiselle esivanhemmalle. Ataksiasairauksien tautimekanismeja selvitimme tutkimalla MIRAS-ataksiaa ja sitä muistuttavaa IOSCA sairautta (infantile onset spinocerebellar ataxia), jonka aiheuttaa peittyvästi periytyvä geenivirhe Twinkle-geenissä. Tutkimuksessa löydettiin myös uusi, Twinkle-geenin geenivirheestä johtuva taudinkuva: vaikea-asteinen, varhaisella iällä alkava aivosairaus, jossa on lisäksi viitteitä maksasairaudesta. Löysimme potilaiden aivoista muutoksia mitokondrioiden eli solun voimalaitosten perimän määrässä. Nämä tulokset antavat arvokasta lisätietoa ataksiasairauksien taustalla olevista muutoksista, joiden ymmärtäminen on välttämätön edellytys hoitomahdollisuuksien tutkimiselle tulevaisuudessa.
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Rather than a single focus on assessing risk and diagnosing deficit, this book recognises that our child protection systems bear down disproportionately on those from disadvantaged and marginalised communities and argues that what is needed is real support and practical assistance for poor and vulnerable parents and children. It uses real-world case examples to illustrate the relevant ethical and practice principles, and ways in which students and practitioners can practise ethically when dealing with complex, multi-faceted issues.
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<正> 高模玻璃纤维增强复合材料大大改善了一般玻璃钢弹性模量不够高的弱点,成为一种轻质、高强、高模及抗疲劳断裂、抗冲击并且减振性、容伤性好的高性能复合材料,应用于航空、航天及其它重量要求严格的产品作为结构材料。复合材料圆管是一种受力型式合理的结构元件,不仅适用于需要管子形状的构件,同时对受压杆和承弯曲是有利的;而且对用圆管作为各向异性复合材料制造的性能试验件也相当合理的,封闭的管状试件能避免板状试件自由边缘应力分布不均匀的问题,因此
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Ao contrário do que propaga a maioria da crítica, Aluísio Azevedo não foi um escritor exclusivamente naturalista. Em sua diversificada produção literária encontramos peças teatrais, escritas individualmente, em parceria com o irmão Artur Azevedo ou com o amigo Emílio Rouède; romances-folhetim, que asseguravam sua sobrevivência; narrativas que podem inscrever-se no gênero fantástico, como os contos Demônios e O impenitente, bem como o romance A mortalha de Alzira; e ainda uma surpreendente novela policial, Mattos, Malta ou Matta? Toda a sua obra, seja ela dramatúrgica ou narrativa, revela-nos um escritor em conflito, dividido entre a necessidade de ganhar dinheiro e o desejo de escrever de acordo com suas próprias convicções. Este trabalho busca destacar e discutir algumas vertentes estéticas de sua obra literária relegadas pela crítica e em geral pouco conhecidas: a narrativa romântica, a policial, a fantástica e sua criação teatral
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给出了以413nm作为写入波长,1053nm作为使用波长的多层介质光栅膜的设计,计算表明膜系H3L(H2L)·9H0.5L2.03H满足光栅膜的要求.最后给出了制备得到的样品光学特性测试,结果表明在使用渡长和曝光波长处满足设计要求,其抗激光损伤阈值在光正入射和51.2°入射时分别为14.14J/cm^2和9.32J/cm^2,膜系的应力表现为压应力.