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Global analysis of gene expression reveals mRNA superinduction is required for the inducible immune response to a bacterial pathogen.
The inducible innate immune response to infection requires a concerted process of gene expression that is regulated at multiple levels. Most global analyses of the innate immune response have focused on transcription induced by defined immunostimulatory ligands, such as lipopolysaccharide. However, the response to pathogens involves additional complexity, as pathogens interfere with virtually every step of gene expression. How cells respond to pathogen-mediated disruption of gene expression to nevertheless initiate protective responses remains unclear. We previously discovered that a pathogen-mediated blockade of host protein synthesis provokes the production of specific pro-inflammatory cytokines. It remains unclear how these cytokines are produced despite the global pathogen-induced block of translation. We addressed this question by using parallel RNAseq and ribosome profiling to characterize the response of macrophages to infection with the intracellular bacterial pathogen Legionella pneumophila. Our results reveal that mRNA superinduction is required for the inducible immune response to a bacterial pathogen
Applying Virtual Reality Techniques to Sensitivity-Based Structural Shape Design
Virtual reality (VR) provides a design space consisting of three-dimensional computer images where participants can interact with these images using natural human motions in real time. In the field of engineering design, prototyping and design verification have provided the initial application areas for VR. The research presented in this paper takes the scenario one step further by incorporating free-form deformation techniques and sensitivity analysis into the virtual world such that the designer can easily implement analysis-based shape design of a structural system where stress considerations are important. NURBS-based free-form deformation (NFFD) methods and direct manipulation techniques are used as the interface between the VR interaction and the finite element model. Sensitivity analysis is used to allow the designer to change the design model and immediately view the effects without performing a re-analysis. An engine connecting rod is analyzed to demonstrate how virtual reality techniques can be applied to structural shape design
Experimental verification and practical application of torquewhirl theory of rotordynamic instability
A theory developed by Vance in 1978 to explain the destabilizing effect of torque on a whirling rotor was experimentally verified. The measurements made on a specially designed test apparatus are described. New computer models were also developed to investigate the effect of torque on rotordynamic stability of multidisk flexible rotor bearing systems. The effect of torque was found to be most pronounced when the system is already marginally stable from other influences. The modifications required to include torque in a typical shaft transfer matrix are described, and results are shown which identify the type of rotor design most sensitive to load torque
Expanding neurosurgery
pre-printThe history of medicine is replete with innovations in neurosurgery that have spurred further developments across the medical spectrum. Surgeons treating pathologies in the head and spine have broken ground with new approaches, techniques, and technologies since ancient times. Neurosurgeons occupy a vital nexus in patient care, interfacing with the clinical symptoms and signs afflicting patients, the pathology at surgery, and imaging studies. No other physicians occupy this role within the nervous system. This power of observation and the ability to intercede place neurosurgeons in a unique position for impacting disease. Yet despite these pioneering achievements, more recently, forces in the workplace may be challenging neurosurgery's opportunities to contribute to the future growth of the neurosciences and medicine. The authors posit that, in the current health care climate, revenue generation by neurosurgical clinical activity is valued by the system more than neurosurgical research and academic output. Without providing the talented stream of new neurosurgeons with the opportunities and, in fact, the directive to achieve beyond simple financial success, the specialty is missing the opportunity to optimize its progress. The authors contend that the key to remaining relevant with the incorporation of new technologies to the treatment of neurosurgical patients will be to be flexible, open-minded, and nimble with the adaptation of new procedures by training and encouraging neurosurgical residents to pursue new or neglected areas of the specialty. Only by doing so can neurosurgery continue to expand
Robust Software
Agents offer a convenient level of granularity at which to add redundancy a key factor in developing robust software. Blindly adding code introduces more errors, makes the system more complex, and renders it harder to understand. However, adding more code can make software better, if it is added in the right way. As this article describes, the key concepts appear to be redundancy and the appropriate granularity
Model independent shape analysis of correlations in 1, 2 or 3 dimensions
A generic, model-independent method for the analysis of the two-particle
short-range correlations is presented, that can be utilized to describe e.g.
Bose-Einstein (HBT or GGLP), statistical, dynamical or other short-range
correlation functions. The method is based on a data-motivated choice for the
zero-th order approximation for the shape of the correlation function, and on a
systematic determination of the correction terms with the help of complete
orthonormal set of functions. The Edgeworth expansion is obtained for
approximately Gaussian, the Laguerre expansion for approximately exponential
correlation functions. Multi-dimensional expansions are also introduced and
discussed.Comment: Latex, 15 pages, uses epsfig.sty elsart.sty, misprints correcte
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