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Parallel Lines (parallel + line)
Selected AbstractsLET THERE BE IRONY: CULTURAL HISTORY AND MEDIA ARCHAEOLOGY IN PARALLEL LINESART HISTORY, Issue 5 2005WOLFGANG ERNST Stephen Bann is well known as an art critic, art historian, cultural historian and museologist, but his writings have yet to be discovered from the point of view of media theory. This article applies Bann's proposal of an ,ironical museum' to a self-reflective media culture, while at the same time establishing the difference between a media-archaeological and an art-historical approach, particularly in accounts of new media in the first half of the nineteenth century and in the present. To what extent was the historical imagination developed in the romantic period an effect of new media and new media technologies? It is argued that although the discourse of history has always depended on the media of its representation (verbal and visual), its character changed dramatically with the arrival of mechanical means for recording historical evidence. The ,antiquarian' method of archival investigation of the past, with its almost haptic taste for the mouldy, decaying fragment, is considered and compared to narrative aesthetics. A key question is considered from different disciplinary perspectives: can we speak of a cultural transition or a radical break with the emergence of photography? The essay concludes that what we learn from Stephen Bann's analyses is the significance of an ever-alert awareness of the intricate relations between cultural and technological phenomena, a kind of media self-irony which, apparently, was present in the past to antiquaries and historiographers, to painters, engravers and to creators of historical museums. [source] Turboprop IDEAL: A motion-resistant fat,water separation techniqueMAGNETIC RESONANCE IN MEDICINE, Issue 1 2009Donglai Huo Abstract Suppression of the fat signal in MRI is very important for many clinical applications. Multi-point water,fat separation methods, such as IDEAL (Iterative Decomposition of water and fat with Echo Asymmetry and Least-squares estimation), can robustly separate water and fat signal, but inevitably increase scan time, making separated images more easily affected by patient motions. PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) and Turboprop techniques offer an effective approach to correct for motion artifacts. By combining these techniques together, we demonstrate that the new TP-IDEAL method can provide reliable water,fat separation with robust motion correction. The Turboprop sequence was modified to acquire source images, and motion correction algorithms were adjusted to assure the registration between different echo images. Theoretical calculations were performed to predict the optimal shift and spacing of the gradient echoes. Phantom images were acquired, and results were compared with regular FSE-IDEAL. Both T1- and T2-weighted images of the human brain were used to demonstrate the effectiveness of motion correction. TP-IDEAL images were also acquired for pelvis, knee, and foot, showing great potential of this technique for general clinical applications. Magn Reson Med 61:188,195, 2009. © 2008 Wiley-Liss, Inc. [source] Color constancy from invariant wavelength ratios: I. The empirical spectral mechanismCOLOR RESEARCH & APPLICATION, Issue 3 2008Ralph W. PridmoreArticle first published online: 10 APR 200 Abstract The wavelengths of several constant hues over four illuminants (D95, D65, D50, A) are derived from several sets of published data. In the plane of wavelength and reciprocal illuminant color temperature (MK,1), the wavelengths of constant hues plot straight approximately parallel lines whose mean slope is about 87°. Parallel lines give invariant wavelength ratios, hence constant hues in this plane are near-invariant wavelength ratios across illuminants. As recently demonstrated, the complementary wavelengths to a constant hue (across illuminants) represent the complementary constant hue; these complementary wavelengths also plot a near-parallel line to the first constant hue. To confirm and further define the constant slope of these lines, it is shown that complementary wavelength pairs, per CIE data, can only plot parallel straight lines at the angle of 87° ± 1. In summary, near-parallel sloping lines represent constant hues at near-invariant wavelength ratios. This mechanism of color constancy is shown to relate to the well-known theory of relational color constancy from invariant cone-excitation ratios. In the visual process, the latter ratios are presumably the source of the former (invariant wavelength ratios). © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 238,249, 2008 [source] Statistical aspects of design and validation of microtitre-plate-based linear and non-linear parallel in vitro bioassaysBIOTECHNOLOGY JOURNAL, Issue 1 2010Hanne Zimmermann Abstract Assay validation was performed using four consecutive experiments with the related statistical evaluation. A cell-based assay on microtitre plates measured repeatedly within 1 day and on consecutive days was chosen as the model. The following problems were addressed: (i) choosing an appropriate design on a plate to avoid heterogeneities, (ii) quantification of all sources of variability and (iii) selecting between linear and non-linear parallel line assays. A mixed model was used with the random factors: rows, columns and plates and fixed effect factors with either linear or non-linear parallel line models. [source] Stem Cell Aligned Growth Induced by CeO2 Nanoparticles in PLGA Scaffolds with Improved Bioactivity for Regenerative MedicineADVANCED FUNCTIONAL MATERIALS, Issue 10 2010Corrado Mandoli Abstract Hybrid 2D polymeric,ceramic biosupports are fabricated by mixing a nanostructured CeO2 powder with 85:15 poly(D,L -lactic- co -glycolic acid) (PLGA)/dichloromethane solutions at specific concentrations, followed by solvent casting onto pre-patterned molds. The mold patterning allows the orientation of ceramic nanoparticles into parallel lines within the composite scaffold. The ability of the produced films to host and address cell growth is evaluated after 1, 3, and 6 days of culturing with murine derived cardiac and mesenchymal stem cells (CSCs and MSCs), and compared with PLGA films without ceramics and loaded with nanostructured TiO2. Aligned cell growth is observed only for scaffolds that incorporate oriented ceramic nanoparticles, attributed to the nanoceramic ability to modulate the roughness pitch, thus improving cell sensitivity towards the host surface features. Better CSC and MSC proliferative activity is observed for CeO2 composites with respect to either TiO2 -added or unfilled PLGA films. This evidence may be related to the nanostructured CeO2 antioxidative properties. [source] Integration of Density Multiplication in the Formation of Device-Oriented Structures by Directed Assembly of Block Copolymer,Homopolymer BlendsADVANCED FUNCTIONAL MATERIALS, Issue 8 2010Guoliang Liu Abstract Non-regular, device-oriented structures can be directed to assemble on chemically nanopatterned surfaces such that the density of features in the assembled pattern is multiplied by a factor of two or more compared to the chemical pattern. By blending the block copolymers with homopolymers and designing the chemical pattern rationally, complicated structures such as bends, jogs, junctions, terminations, and combined structures are fabricated. Previously, directed assembly of block copolymers has been shown to enhance the resolution of lithographic processes for hexagonal arrays of spots and parallel lines, corresponding to the bulk morphologies of block copolymer systems, but this is the first demonstration of enhanced resolution for more complicated, device-oriented features. This fundamental knowledge broadens the range of technologies that can be served by the directed assembly of block copolymers. [source] Prediction of two-phase flow distribution in parallel pipes using stability analysisAICHE JOURNAL, Issue 10 2006L. Pustylnik Abstract Two-phase gas liquid flow in pipes is a complex process. One of the problems that is hardly understood is how the two phases are distributed among two or more parallel lines with a common inlet manifold. Steady-state analysis yields multiple steady-state solutions. Linear and nonlinear (simulation) stability analyses are performed in order to determine the actual distribution of the flow that will take place in a real system. The analysis shows that when there are four parallel pipes, for example, the two-phase flow mixture from the common inlet manifold can choose to flow in one, two, three, or in all four pipes, depending on the flow rates of the liquid, and the gas and on the pipes inclination. For low-flow rates of gas and liquid, the flow tends to take place only in one line, while stagnant liquid columns are present in the other three pipes. As the flow rate increases the flow will take place in 2, 3 and finally in 4 pipes. Experimental data confirm the analysis although matching is only approximate. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source] Method for checking label accuracy in barn and free range eggsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2005Neville G Gregory Abstract The aim was to develop a method for testing whether eggs sold as either ,barn' or free range' were laid under cage conditions. The surface patterns on 11 520 eggs from cage, barn and free range production systems were examined under ultraviolet light for distinctive fluorescent marks associated with each production system. In addition, the effects of egg washing, egg size, condensation and cage dusting on the prevalence of the fluorescent patterns associated with the cage production system were examined. The prevalence of fluorescent white double parallel lines with 2.2,2.5 cm spacing was a distinguishing feature for eggs laid on wire floors in cages. If five or more eggs in a sample of 90 eggs have double fluorescent lines it can be concluded with greater than 999 in 1000 probability that the batch contains some cage-laid eggs. Dust from the egg collection area below the feed trough was the main source of the fluorescent material. Washing the eggs removed or obscured the double lines. Egg size and condensation had limited effects on the prevalence of double lines. Infrequent dusting of the wire floor did not reduce the value of the test. Copyright © 2005 Society of Chemical Industry [source] Multishot diffusion-weighted SPLICE PROPELLER MRI of the abdomenMAGNETIC RESONANCE IN MEDICINE, Issue 5 2008Jie Deng Abstract Multishot FSE (fast spin echo)-based diffusion-weighted (DW)-PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) MRI offers the potential to reduce susceptibility artifacts associated with single-shot DW-EPI (echo-planar imaging) approaches. However, DW-PROPELLER in the abdomen is challenging due to the large field-of-view and respiratory motion during DW preparation. Incoherent signal phase due to motion will violate the Carr-Purcell-Meiboom-Gill (CPMG) conditions, leading to destructive interference between spin echo and stimulated echo signals and consequent signal cancellation. The SPLICE (split-echo acquisition of FSE signals) technique can mitigate non-CPMG artifacts in FSE-based sequences. For SPLICE, spin echo and stimulated echo are separated by using imbalanced readout gradients and extended acquisition window. Two signal families each with coherent phase properties are acquired at different intervals within the readout window. Separate reconstruction of these two signal families can avoid destructive phase interference. Phantom studies were performed to validate signal phase properties with different initial magnetization phases. This study evaluated the feasibility of combining SPLICE and PROPELLER for DW imaging of the abdomen. It is demonstrated that DW-SPLICE-PROPELLER can effectively mitigate non-CPMG artifacts and improve DW image quality and apparent diffusion coefficient (ADC) map homogeneity. Magn Reson Med 59:947,953, 2008. © 2008 Wiley-Liss, Inc. [source] Thin film solar modules: the low cost, high throughput and versatile alternative to Si wafersPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 5 2006S. Hegedus Abstract Thin film solar cells (TFSC) have passed adolescence and are ready to make a substantial contribution to the world's electricity generation. They can have advantages over c-Si solar modules in ease of large area, lower cost manufacturing and in several types of applications. Factors which limit TFSC module performance relative to champion cell performance are discussed along with the importance of increased throughput and yield. The consensus of several studies is that all TFSC can achieve costs below 1,$/W if manufactured at sufficiently large scale >100,MW using parallel lines of cloned equipment with high material utilization and spray-on encapsulants. There is significant new commercial interest in TFSC from small investors and large corporations, validating the thin film approach. Unique characteristics are discussed which give TFSC an advantage over c-Si in two specific markets: small rural solar home systems and building integrated photovoltaic installations. TFSC have outperformed c-Si in annual energy production (kWhrs/kW), have demonstrated outdoor durability comparable to c-Si and are being used in MW scale installations worldwide. The merits of the thin film approach cannot be judged on the basis of efficiency alone but must also account for module performance and potential for low cost. TFSC advocates should promote their unique virtues compared to c-Si: lower cost, higher kWhr/kW output, higher battery charging current, attractive visual appearance, flexible substrates, long-term stability comparable to c-Si, and multiple pathways for deposition with room for innovation and evolutionary improvement. There is a huge market for TFSC even at today's efficiency if costs can be reduced. A brief window of opportunity exists for TFSC over the next few years due the Si shortage. The demonstrated capabilities and advantages of TFSC must be proclaimed more persistently to funding decision-makers and customers without minimizing the remaining challenges. Copyright © 2006 John Wiley & Sons, Ltd. [source] Proliferative remodeling of the spatial organization of human superficial chondrocytes distant from focal early osteoarthritisARTHRITIS & RHEUMATISM, Issue 2 2010Bernd Rolauffs Objective Human superficial chondrocytes show distinct spatial organizations, and they commonly aggregate near osteoarthritic (OA) fissures. The aim of this study was to determine whether remodeling or destruction of the spatial chondrocyte organization might occur at a distance from focal (early) lesions in patients with OA. Methods Samples of intact cartilage (condyles, patellofemoral groove, and proximal tibia) lying distant from focal lesions of OA in grade 2 joints were compared with location-matched nondegenerative (grade 0,1) cartilage samples. Chondrocyte nuclei were stained with propidium iodide, examined by fluorescence microscopy, and the findings were recorded in a top-down view. Chondrocyte arrangements were tested for randomness or significant grouping via point pattern analyses (Clark and Evans Aggregation Index) and were correlated with the OA grade and the surface cell densities. Results In grade 2 cartilage samples, superficial chondrocytes were situated in horizontal patterns, such as strings, clusters, pairs, and singles, comparable to the patterns in nondegenerative cartilage. In intact cartilage samples from grade 2 joints, the spatial organization included a novel pattern, consisting of chondrocytes that were aligned in 2 parallel lines, building double strings. These double strings correlated significantly with an increased number of chondrocytes per group and an increased corresponding superficial zone cell density. They were observed in all grade 2 condyles and some grade 2 tibiae, but never in grade 0,1 cartilage. Conclusion This study is the first to identify a distinct spatial reorganization of human superficial chondrocytes in response to distant early OA lesions, suggesting that proliferation had occurred distant from focal early OA lesions. This spatial reorganization may serve to recruit metabolically active units as an attempt to repair focal damage. [source] | |||||||||||||