Progress in 193-nm Single Layer Resists: The role of Photoacid Generator Structure on the Performance of Positive Resists

Author(s):  
Robert D. Allen ◽  
Juliann Opitz ◽  
Carl E. Larson ◽  
Thomas I. Wallow ◽  
Richard A. DiPietro ◽  
...  
2009 ◽  
Vol 6 (suppl_2) ◽  
Author(s):  
Rafael Maia ◽  
João Victor O Caetano ◽  
Sônia N Báo ◽  
Regina H Macedo

Iridescent coloration plays an important role in the visual communication system of many animal taxa. It is known that iridescent structural colours result from layers of materials with different refractive indexes, which in feathers usually are keratin, melanin and air. However, the role of these materials in the production of structural iridescent coloration is still poorly documented. Despite the great interspecific variation in the organization of such structures in bird plumage, melanin layers are usually considered too opaque, suggesting its main role is to delineate the outermost keratin layer and absorb incoherently scattered stray light. We combined spectrometry, electron microscopy and thin-film optical modelling to describe the UV-reflecting iridescent colour of feather barbules of male blue-black grassquits ( Volatinia jacarina ), characterized by a keratin layer overlying a single melanin layer. Our models indicate that both the keratin and the melanin layers are essential for production of the observed colour, influencing the coherent scattering of light. The melanin layer in some barbules may be thin enough to allow interaction with the underlying keratin; however, individuals usually have, on an average, the minimum number of granules that optimizes absorbance by this layer. Also, we show that altering optical properties of the materials resulted in better-fitting models relative to the empirically measured spectra. These results add to previous findings concerning the influence of melanin in single-layer iridescence, and stress the importance of considering natural variation when characterizing such photonic structures.


2002 ◽  
Author(s):  
Gerd Pohlers ◽  
Yasuhiro Suzuki ◽  
Nicholas Chan ◽  
James F. Cameron

2021 ◽  
Author(s):  
Agnieszka Zienkiewicz ◽  
Marta Saldat ◽  
Krzysztof Zienkiewicz

In plants, lipids serve as one of the major and vital cellular constituents. Neutral lipids reserves play an essential role in the plant life cycle by providing carbon and energy equivalents for periods of active metabolism. The most common form of lipid storage are triacylglycerols (TAGs) packed into specialized organelles called lipid droplets (LDs). They have been observed in diverse plant organs and tissues, like oil seeds or pollen grains. LDs consist of a core, composed mostly of TAGs, enclosed by a single layer of phospholipids that is decorated by a unique set of structural proteins. Moreover, the recent advances in exploration of LDs proteome revealed a plethora of diverse proteins interacting with LDs. This is likely the result of a highly dynamic nature of these organelles and their involvement in many diverse aspect of cellular metabolism, tightly synchronized with plant developmental programs and directly related to plant-environment interactions. In this review we summarize and discuss the current progress in understanding the role of LDs and their cargo during plants life cycle, with a special emphasis on developmental aspects.


2001 ◽  
Author(s):  
Francis M. Houlihan ◽  
Donna Person ◽  
Omkaram Nalamasu ◽  
Ilya Rushkin ◽  
Ognian N. Dimov ◽  
...  

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Vladimir M Subbotin

Objectives Tremendous success of statins in coronary atherosclerosis (CA) prevention offered great expectations for extended protection and effective therapeutics. However, stalled progress in pharmaceutical treatment gives a good reason to review whether the hypothesis underlining our efforts is consistent with undoubted facts on coronary artery in normal and diseased forms. Analysis An accepted hypothesis states that CA is initiated by endothelial dysfunction due to inflammation and high levels of LDL, followed by lipids and macrophage penetration into arterial intima and plaque formation. It is crucial to highlight that normal coronary intima is not a single-layer endothelium covering thin acellular compartment, as is commonly claimed in most publications, but always appears as a multi-layer cellular compartment, or diffuse intimal thickening (DIT), where cells are arranged in a few dozens layers. Since it is unanimously agreed that LDL invade DIT from lumen, the initial depositions ought to be most proximal to blood, i.e. in inner DIT layers. The facts show that the opposite is true, and lipids are deposited in the outer DIT. This contradiction is resolved by noting that normal DIT is always avascular, receiving oxygen and nutrients by diffusion from lumen, whereas in CA outer DIT is always neovascularized from adventitial vasa vasorum . Proteoglycan biglycan, confined to outer DIT of normal and diseased coronary, has high binding capacity for LDL. However, normal DIT is avascular, whereas in CA biglycan of outer DIT layers appears in direct contact with blood and extract lipoproteins. These facts explain patterns and mechanisms of CA initiation, which is not unique: normally avascular cornea accumulates lipoproteins after neovascularization, resulting in lipid keratopathy. The author offers a hypothesis on neovascularization. Cells in coronary DIT possess high proliferative capacity. Excessive cell replication increases DIT thickness, impairs diffusion, resulting in hypoxia of outer DIT. Hypoxia induces neovascularization of outer DIT layers, where biglycan extracts LDL from newly formed capillary bed, initiating CA. Conclusion Controls of cell proliferation and neovascularization in coronary DIT should be a priority of our research.


2019 ◽  
Vol 49 (9) ◽  
pp. 2393-2406 ◽  
Author(s):  
Carsten Eden ◽  
Manita Chouksey ◽  
Dirk Olbers

AbstractGravity wave emission by geostrophically balanced flow is diagnosed in numerical simulations of lateral and vertical shear instabilities. The diagnostic method in use allows for a separation of balanced flow and residual wave signal up to fourth order in the Rossby number (Ro). While evidence is found for a small but finite gravity wave emission from balanced flow in a single-layer model with large lateral shear and large Ro, a vertically resolved model with moderate velocity amplitudes appropriate to the interior ocean hardly shows any wave emission. Only when static instabilities generated by the shear instability of the balanced flow are allowed can a gravity wave signal similar to the ones reported in earlier studies be detected in the vertically resolved case. This result suggests a relatively small role of spontaneous wave emission in the classical sense of Lighthill radiation, and emphasizes the role of convective or symmetric instabilities during frontogenesis for the generation of internal gravity waves in the ocean and atmosphere.


2019 ◽  
Vol 128 (6_suppl) ◽  
pp. 76S-83S ◽  
Author(s):  
Sung Huhn Kim ◽  
Gi-Sung Nam ◽  
Jae Young Choi

Background: The endolymphatic sac (ES) is a cystic structure situated on the posterior fossa dura and is connected to the luminal space of the vestibular organ through the endolymphatic duct, which branches into the utricular and saccular ducts. Unlike the cochlea and vestibule, the ES does not contain sensory epithelium in its luminal space, and a single layer of epithelial cells line the luminal surface area. The ES in the inner ear is thought to play a role in the regulation of inner ear homeostasis, fluid volume, and immune reaction. If these functions of the ES are disrupted, dysfunction of the inner ear may develop. The most well-known pathology arising from dysfunction of the ES is endolymphatic hydrops, characterized by an enlarged endolymphatic space due to the accumulation of excessive endolymphatic fluid. Although, molecular identities and functional evidence for the roles were identified in animal studies, basic studies of the human ES are relatively uncommon compared with those using animal tissues, because of limited opportunity to harvest the human ES. Methods: In this study, molecular and functional evidence for the role of the human ES in the development of endolymphatic hydrops are reviewed. Results and Conclusions: Although evidence is insufficient, studies using the human ES have mostly produced findings similar to those of animal studies. This review may provide a basis for planning further studies to investigate the pathophysiology of disorders with the finding of endolymphatic hydrops.


1996 ◽  
Vol 35 (Part 2, No. 4B) ◽  
pp. L528-L530 ◽  
Author(s):  
Koji Nozaki ◽  
Keiji Watanabe ◽  
Takahisa Namiki ◽  
Miwa Igarashi ◽  
Yoko Kuramitsu ◽  
...  
Keyword(s):  

1998 ◽  
Vol 528 ◽  
Author(s):  
T. L. Einstein ◽  
S. V. Khare ◽  
O. Pierre-Louis

AbstractExperimental advances in recent years make possible quantitative observations of step-edge fluctuations. By applying a capillary-wave analysis to these fluctuations, one can extract characteristic times, from which one learns about the mass-transport mechanisms that underlie the motion as well as the associated kinetic coefficients [1-3]. The latter do not require a priori insight about the microscopic energy barriers and can be applied to situations away from equilibrium. We have studied a large number of limiting cases and, by means of a unified formalism, the crossover between many of these cases[4]. Monte Carlo simulations have been used to corroborate these ideas. We have considered both isolated steps and vicinal surfaces; illustrations will be drawn from noble-metal systems, though semiconductors have also been studied. Attachment asymmetries associated with Ehrlich-Schwoebel barriers play a role in this behavior. We have adapted the formalism for nearly straight steps to nearly circular steps in order to describe the Brownian motion of single-layer clusters of adatoms or vacancies on metal surfaces, again in concert with active experimental activity [3,5]. We are investigating the role of external influences, particularly electromigration, on the fluctuations.


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