An unequal modulation scheme for the transmission of compressed multimedia data over MIMO-OFDM systems

Modern video/image source coders employ data compression techniques which encode information that are not equally important. Transform based or subband coders, compress data into their respective low-frequency and high-frequency components. In wireless/mobile communication systems, data representing the low-frequency components are more sensitive to the time-varying nature of channel conditions and propagation environments. To deal with this problem, we propose an optimum transceiver structure for a combined source-modulation coded MIMO-OFDM system with adaptive eigen-beamforming. Using an unequal adaptive modulator, we maximize the channel-to-noise ratio (CNR) based on a lookup matrix-adaptive bit and power allocation (LM-ABPA) scheme to sort and allocate subcarriers with the highest SNR to the low-frequency components of the compressed data, and adjusting the signal constellation/modulation type respectively. In comparison to other transmission systems, simulation results based on the application of compressed images showed that the proposed unequal adaptive modulation scheme achieves significant performance gains under a constant data rate loa

Tetrafurcation of the subscapular artery. Anatomical and clinical implications

Anatomic variations of axillary artery branches are commonly encountered during radiological investigation and surgical operations. Their existence can confuse interpretation of radiological results and lead to undesired complications during surgery. In this report authors describe a rare case of a subscapular arterial trunk that gave origin to thoracodorsal, circumflex scapular, posterior humeral circumflex, and lateral thoracic artery. Such a variation might cause undesired sequelae during trauma management and a variety of common flap harvesting operations including latissimus dorsi, scapular and parascapular flaps. Furthermore it presents embryological interest as it gives insight to embryologic development of axillary area

The conceptual design of SeamFrame

This project deliverable provides the underlying architecture of a concept for linking models and databases and it provides the design of SeamFrame, delivering its architecture to provide an integration framework for models and simulation algorithms, supported by procedures for data handling and spatial representation, quality control, output visualization and documentatio

Affine and toric hyperplane arrangements

We extend the Billera-Ehrenborg-Readdy map between the intersection lattice and face lattice of a central hyperplane arrangement to affine and toric hyperplane arrangements. For arrangements on the torus, we also generalize Zaslavsky's fundamental results on the number of regions.Comment: 32 pages, 4 figure

CD4-Transgenic Zebrafish Reveal Tissue-Resident Th2- and Regulatory T Cell-like Populations and Diverse Mononuclear Phagocytes.

CD4+ T cells are at the nexus of the innate and adaptive arms of the immune system. However, little is known about the evolutionary history of CD4+ T cells, and it is unclear whether their differentiation into specialized subsets is conserved in early vertebrates. In this study, we have created transgenic zebrafish with vibrantly labeled CD4+ cells allowing us to scrutinize the development and specialization of teleost CD4+ leukocytes in vivo. We provide further evidence that CD4+ macrophages have an ancient origin and had already emerged in bony fish. We demonstrate the utility of this zebrafish resource for interrogating the complex behavior of immune cells at cellular resolution by the imaging of intimate contacts between teleost CD4+ T cells and mononuclear phagocytes. Most importantly, we reveal the conserved subspecialization of teleost CD4+ T cells in vivo. We demonstrate that the ancient and specialized tissues of the gills contain a resident population of il-4/13b-expressing Th2-like cells, which do not coexpress il-4/13a Additionally, we identify a contrasting population of regulatory T cell-like cells resident in the zebrafish gut mucosa, in marked similarity to that found in the intestine of mammals. Finally, we show that, as in mammals, zebrafish CD4+ T cells will infiltrate melanoma tumors and obtain a phenotype consistent with a type 2 immune microenvironment. We anticipate that this unique resource will prove invaluable for future investigation of T cell function in biomedical research, the development of vaccination and health management in aquaculture, and for further research into the evolution of adaptive immunity.European Research Council (Grant IDs: ERC-2011-StG-282059 (PROMINENT), 677501 (ZF_Blood)), Biotechnology and Biological Sciences Research Council (Grant ID: BB/L007401/1), Dowager Countess Eleanor Peel Trust (Grant ID: TH-PRCL.FID2228), Medical Research Council, Department for International Development (Career Development Award Fellowship MR/J009156/1), Medical Research Foundation (Grant ID: R/140419), Cancer Research UK (Grant ID: C45041/A14953), Wellcome Trust and Medical Research Council to the Wellcome Trust–Medical Research Council Cambridge Stem Cell Institute (core support grant)This is the final version of the article. It first appeared from The American Association of Immunologists via https://doi.org/10.4049/​jimmunol.160095

Direct imaging of changes in aerosol particle viscosity upon hydration and chemical aging

Organic aerosol particles (OA) play major roles in atmospheric chemistry, climate, and public health. Aerosol particle viscosity is highly important since it can determine the ability of chemical species such as oxidants, organics or water to diffuse into the particle bulk. Recent measurements indicate that OA may be present in highly viscous states, however, diffusion rates of small molecules such as water are not limited by these high viscosities. Direct observational evidence of kinetic barriers caused by high viscosity and low diffusivity in aerosol particles were not available until recently; and techniques that are able to dynamically quantify and track viscosity changes during atmospherically relevant processes are still unavailable for atmospheric aerosols. Here we report quantitative, real-time, online observations of microscopic viscosity changes in aerosol particles of atmospherically relevant composition, using fluorescence lifetime imaging (FLIM) of viscosity. We show that microviscosity in ozonated oleic acid droplets and secondary organic aerosol (SOA) particles formed by ozonolysis of myrcene increases substantially with decreasing humidity and atmospheric oxidative aging processes. Furthermore, we found unexpected heterogeneities of microviscosity inside individual aerosol particles. The results of this study enhance our understanding of organic aerosol processes on microscopic scales and may have important implications for the modeling of atmospheric aerosol growth, composition and interactions with trace gases and clouds.Engineering and Physical Sciences Research Council (Career Acceleration Fellowship (Grant ID: EP/I003983/1), Prize studentship), Natural Environment Research Council (Studentship NE/J500070/1), European Research Council (Grant ID: 279405), Max Planck Society, European Union project PEGASOS (Grant ID: 265148

Trade-offs in the design of cross-disciplinary software systems

As researchers we are often faced with the difficult and demanding task of preparing models, and their computer implementations, for decision making, or, more recently, for integrated assessment. Such assessment often involves large scale problems, where the decisions to be made can deeply affect the environment, the social context and the economic background of regions and even nations. Yet, we face the grim reality that a model is a focused representation of the world, and it is always a result of several compromises in terms of details and structure, leading to trade-offs in terms of complexity, flexibility and performance. This trade-off becomes an essential design property. We often wish our models to be as simple as possible, balancing transparency, understandability and level of detail. Now, we are involved in the SEAMLESS project, an EU FP6 Integrated Project, aims at generating an integrated framework of computer models. This framework can be used for assessment of how future alternative agricultural and environmental polices affect sustainable development in Europe. Thus, we are designing a cross disciplinary software system to deal with different simulation domains. In this, we need to take care of many differences between the different modeling societies. We decided to apply an architecture centric development method and evaluated this with stakeholders based on a so-called Architecture Trade-off Analysis method. When prioritizing the requirements we used a cost-benefit analysis as a weighting factor for deciding what to do first. Requirements were grouped in user-roles, that appeal to differences in user-interface options. The resulting software architecture identified the necessity to identify two major blocks: the modeling environment, to be used by a number of user roles, mostly modelers and coders, and the processing environment, which is oriented towards the needs of those user roles more focused on system analysis, rather than design and implementation. Another key factor of our architecture is the knowledge base, which provides a common repository for all knowledge, data, model sources which are shared by the two environments. When moving on from architecture to design and implementation, we tried to steer clear of the risk of inventing another modelling framework, and therefore in our prototype we use different existing frameworks for different tasks in the overall design. This means that we discussed the view that 'one tool fixes everything', and we chose to rely on specific frameworks for specific needs. We chose a modelling framework with a track record in crop modeling, to target our biophysical modeling needs, and we selected a de facto standard framework for economic modeling to solve agri-economic modelling problems. All of this comes at a price, that is the extra effort required to integrate different frameworks. We chose therefore to develop an evolution of the OpenMI integration framework to target this issue. In this article we describe all the risks we have identified as associated to our architecture centric approach and how we dealt with them. This article describes the design of the modeling framework for SEAMLESS. A first prototype is ready in January 2006