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In this study we report on initial efforts to discover putative biomarkers for differential diagnosis of a systemic inflammatory response syndrome (SIRS) vs. sepsis; and different stages of sepsis. In addition, we also investigated whether there are proteins that can discriminate between patients who survived sepsis from those who did not. Our study group consisted of 16 patients, of which 6 died and 10 survived. We daily measured 28 plasma proteins, for the whole stay of the patients in the ICU. We observed that metalloproteinases and sE-selectin play a role in the distinction between SIRS and sepsis, and that IL-1a, IP-10 and sTNF-R2 and sFAS appear to be indicative for the progression from sepsis to septic shock. A combined measurement of MMP-3, -10, IL-1a, IP-10, sIL-2R, sFas, sTNF-R1, sRAGE, GM-CSF,IL-1ß, and Eotaxin allows for a good separation of patients that survived from those that died (mortality prediction with a sensitivity of 79% and specificity of 86%). Correlation analysis suggests a novel interaction between IL-1a and IP-10. The marker panel is ready tobe verified in a validation study with or without therapeutic intervention.

We present the design of an algorithm for use in an interactivemusic system that automatically generates music playlists that fit the music preferences of a user. To this end, we introduce a formal model, define the problem of automatic playlist generation (APG), and proof its NP-hardness. We use a local search (LS)procedure employing a heuristic improvement to standard simulated annealing (SA) to solve the APG problem. In order to employ this LS procedure, we introduce an optimization variant of the APG problem, which includes the definition of penalty functions and a neighborhood structure. To improve upon the performance of the standard SA algorithm, we incorporated three heuristics referred to as song domain reduction, partial constraint voting, an da two-level neighborhood structure. We evaluate the developed algorithm by comparing it to a previously developed approach based on constraint satisfaction (CS),both in terms of run time performance and quality of the solutions. For the latter we not only considered the penalty of the resulting solutions, but we also performed a conclusive user evaluation to assess the subjective quality of the playlists generated by both algorithms. In all tests, the LS algorithm was shown to be a dramatic improvement over the CS algorithm.

Video processing in software is often characterized by highly fluctuating, content-dependent processing times, and a limited tolerance for deadline misses. We present an approach that allows close-to-average-case resource allocation to a single video processing task, based on asynchronous, scalable processing, and QoS adaptation. The QoS adaptation balances different QoS parameters that can be tuned by user-perception experiments: picture quality, deadline misses, and quality changes. We model the balancing problem as a discrete stochastic decision problem, and propose two closely related solution strategies, for which the processing-time statistics are determined off line and at run time, respectively. We enhance both strategies with a compensation for structural (non-stochastic) load fluctuations. Finally, we validate our approach by means of simulation experiments, and conclude that both enhanced strategies perform close to the theoretical optimum.

The just noticeable difference (JND) in black level (BL), whitelevel (WL), and chroma as visible in natural images under practical viewing conditions is determined. The potential effect of cultural background on the JNDs is evaluated conducting the same experiment in China and in the Netherlands. In general, there is a big difference in JND depending on the content of the natural image, as we expected. Only for some images,we found a difference in JND between China and the Netherlands. It seems that for these images people on average were looking to a different area in the image during their assessment

The ion emission of a Sn-based discharge produced extreme ultraviolet producing plasma is characterized with the combined use of different time-of-flight techniques. An electrostatic ion spectrometer isemployed to measure the average charge distribution of the emitted Sn ions. A dedicated Faraday cup configuration is used to measure thetotal ion flux from the source for different discharge energies.High-energy Sn ions emitted by the plasma with energies up to 100keV have been identified. The number of high-energy ions increasesfor higher electrical input energy into the plasma while the signalassociated with the expanding plasma ions does not show such depen-dence. The ion energy distribution for a bulk of detected ions iscalculated based on the Faraday cup measurements and compared withtheoretical plasma expansion dynamics.

Purpose: X-ray based tomographic blood perfusion imaging requires recovery of contrast time-attenuation-curves from dynamic projection data. When using slowly rotating imaging systems this task is challenging due to non-simultaneous projection acquisition. A dynamic reconstruction method is proposed that aims at compensating the lack of simultaneously acquired information by incorporating prior knowledge about the expected temporal contrast dynamics. Methods: A decomposition model using temporal basis functions to approximate time-attenuation-curves is integrated into an iterative tomographicre construction method. The computationally efficient implementationof the proposed approach makes use of standard forward- and back projections as well as scalar products in image space. The critical issue of projection noise propagation is tackled by application of regularization which is realizedby early stopping of iteration cycles and by proper selection of smooth temporal basis functions. The performance of the proposed dynamic reconstruction approach is evaluated in a simulation study concerning various aspects: noise propagation and regularization, specification of temporal model, and type of acquisition mode. Results: The evaluation based on dynamic phantom data indicates that tomographic recovery of contrast time-attenuation-curves in tissue can be achieved with an average range of accuracy of ca. 2% (with respect todynamic peak attenuation) under ideal noise-free conditions. The relative estimation error for arterial time-attenuation-curves is in the range of 8%, which is due to faster contrast dynamics in the artery. In general, performance depends on the level of acquired information contained in the projection data which is mainly influenced by the type of rotational acquisition mode; restrictions in angular range and speed can lead to limited accuracy. The analysis of propagated projection noise in a statistical Bias-Variance framework reveals relative noise levels in estimated time-attenuation-curves of 3-4% intissue regions and below 1% in vessels when using optimized settingsfor regularization. Here, the effect of noise suppression depends oninterrelation between the model. Conclusions: For usage with slowly rotating imaging systems the presented model-based iterative dynamic reconstruction method is capable of recovering contrast time-attenuation-curves related to tissue perfusion. The proposed regularization framework is an effective means to limit the impact of projection noise which is a factor dominating estimation accuracy in tissue regions.

The lack of understanding of the mechanical behavior of the human skin layers makes the development of drug delivery using microneedles or microjets a challenging task. In particular, the key mechanical properties of the epidermis composed of stratum corneum and viable epidermis, should be better understood. Micro-indentation experiments were applied, using a spherical tip with a large diameter to the sample thickness ratio. The Young's moduli were derived via an analytical and a numerical method. The tests showed that the analytical method was not appropriate to assess the Young's moduli. That is why a numerical model was used to obtain the correct stiffness. When loaded perpendicularly, the stiffness of both the epidermis and stratum corneum vary between 1 and 2 MPa. No significant differences in stiffness between the stratum corneum and viable epidermis were observed.

A systematic investigation into halides and ~oxides showed the high potential of transition metal oxides as visible radiators for highly efficient gas discharge light sources. Zirconium monoxide (ZrO) has been identified as most promising candidate combining highly attractive green and red emission band systems with very high dissociation energy (8.2eV) which assures that the molecule is stable even in the hot plasma centre. Thus far, however, it has been impossible to keep ZrO in the gas phase of a closed discharge vessel, because at wall temperature usually compounds are formed which have negligible vapour pressures. We succeeded in establishing a regenerative chemical cycle by filling ZrX4 (X=Cl, Br, I) together with a stable, but volatile oxygen compound (like MoO2X2) and realized thus highly attractive, novel gas discharge light sources.

Localized surface plasmon polaritons (LSPPs) provide an efficient means of achieving extreme light concentration. In recent years, their active control has become a major aspiration of plasmonic research. Here, we demonstrate direct control of semiconductor bowtie antennas, enabling active excitation of LSPPs, at terahertz (THz) frequencies. We modify the LSPPs by ultrafast optical modulation of the free carrier density in the plasmonic structure itself, allowing for active control of the semiconductor antennas on picosecond timescales. Moreover, this control enables the manipulation of the field intensity enhancements in ranges of four orders of magnitude.

The stability of an electrowetting system is dependent upon the choice of liquids, the dielectric material and the operating voltage.Substantial progress is reported herein on use of 300 nm thick poly-tetrafluoro-para-xylylene) (Parylene HT) films for almost 100° of reliable electrowetting modulation at only 15 V. Not only does Parylene HT exhibit improved resistance to dielectric failure as compared to poly(2-chloro-para-xylylene) (Parylene C), but Parylene HT is shown to sustain continuous DC electrowetting to <70° for > 6 hours. Furthermore, Parylene HT has a surface energy such that when electrowetting in an alkane oil ambient, a Young’s angle of about 170° can beachieved without the traditional fluoropolymer top-coat. Also presented is a new and simple model for calculating electric field enhancement when electrowetting in an oil bath. It is shown that Parylene HT is a promising candidate for low-voltage and large-area electrowetting devices such as displays and lab-on-chip.

Using the inverse-electron-demand Diels Alder reaction we demonstrated non-invasive pretargeted tumor imaging in mice bearing LS174T colorectal xenografts. Anti-TAG72 mAb CC49 functionalized with trans-cyclooctene moieties was administered, followed 24 h later by 111In-labeled tetrazine. Pronounced tumor uptake of the 111In-tetrazine was demonstrated by SPECT/CT imaging of live mice up to 3 h post injection (tumor-to-muscle ratio: 13.1), while no tumor binding occurred in mice treated with unmodified CC49. The components exhibited a remarkable 52-57 % chemical reaction yield in mice. We are currently optimizing this system for cancer therapy.

Multi-access networks may exhibit severe unfairness in throughput,in the sense that some nodes receive structurally higher throughputthan others. Recent studies show that this unfairness is due tolocal differences in the neighborhood structure: Nodes with fewerneighbors receive better access. We study the unfairness in satura-ted linear networks,and adapt the multi-access CSMA protocol toremove the unfairness completely,by choosing the activation ratesof nodes as a specific function of the number of neighbors. We theninvestigate the consequences of this choice of activation rates onthe network-average saturated throughput, and we show that theserates perform well in non-saturated settings.

Background: Percutaneous cardiac interventions are currently performed under X-ray guidance. Magnetic resonance imaging has been employed to guide intravascular interventions in the past, but mainly in animals. Translation of MR-guided interventions into humans has been limited by the lack of fully MR-compatible and safe devices, such as MR guidewires with mechanical characteristics similar to standard guidewires. The aim of the present study was to evaluate the safety and efficacy of a newly developed MR-safe and compatible passive guidewire in aiding MR-guided cardiac interventions in a swine model and describe the two first-in-man solely MR-guided interventions. Methods and Results: In the preclinical trial, the new MR compatible wire aided the performance of 20 interventions in 5 swine. These consisted of balloon dilation of nondiseased pulmonary and aortic valves, aortic arch and branch pulmonary arteries. Catheter manipulations were monitored with real time MRI sequence with interactive modification of imaging plane and slice position. Following ethics and regulatory authority approval the two first-in-man MR-guided interventions were performed in a child and an adult, both with elements of valvar pulmonary stenosis. Both patients had successful relief of the valvar stenosis and were discharged home a few hours later with no complications. Conclusions: The described pre-clinical study and case reports are encouraging that with the availability of the new MR compatible and safe guidewire, certain percutaneous cardiac interventions will become feasible to perform solely under MR-guidance. The benefits are clear with elimination of the use of ionising radiation and improvement of visualisation of the target lesions.

Many approaches to facial expression recognition focus on assessing the six basic emotions (anger, disgust, happiness, fear, sadness, and surprise). Real-life situations proved to produce many more subtle facial expressions. A reliable way of analyzing the facial behavior is the Facial Action Coding System (FACS) developed by Ekman and Friesen, which decomposes the face into 46 action units (AU) and is usually performed by a human observer. Each AU is related to the contraction of one or more specific facial muscles. In this study we present an approach towards automatic AU recognition enabling recognition of an extensive palette of facial expressions. As distinctive features we used motion flow estimators between every two consecutive frames, calculated in special regions of interest (ROI). Even though a lot has been published on the facial expression recognition theme, it is still difficult to draw a conclusion regarding the best methodology as there is no common basis for comparison. Therefore our main contributions reside in the comparison of different ROI selections proposed by us, different optical flow estimation methods, and also in the comparison of two spatial-temporal classification methods: Hidden Markov Models (HMM) and Dynamic Bayesian Networks (DBN). The classifiers have been trained and tested on the Cohn-Kanade database. The experiments showed that under the same conditions regarding initialization, labeling and sampling, both methods produced similar results, achieving the same recognition rate of 89% for the classification of facial AUs. Still, by enabling non-fixed sampling and using HTK, HMMs rendered a better performance of 93% suggesting that are better suited for the special task of AUs recognition.

Facial image analysis, including face detection, face recognition,facial expression analysis, facial demographic classification, and so on, is an important and interesting research topic in the computervision and image processing area, which has many important applications such as human-computer interaction and visual surveillance. Acritical step for successful facial image analysis is to derive an effective facial representation from the original face images. In recent years, Local Binary Patterns (LBP) has received increasing attention for facial description. This paper presents a comprehensive survey of LBP methodology in the context of facial image analysis. Different aspects are addressed, including recent development of LBP, LBP feature selection, its applications in different facial image analysis tasks and existing systems, and so on. With more than 100 papers reviewed, this is the first extensive review on LBP-based facial image analysis.

X-ray attenuation properties of matter (i.e. human body in medicalComputed Tomography) are energy and material dependent. This dependency is largely neglected in conventional CT techniques, which require the introduction of correction algorithms in order to prevent image artefacts. The exploitation of the inherent energy information contained in the x-ray spectrum allows distinguishing the two main physical causes of energy-dependent attenuation (photo-electric effect and Compton effect). Currently a number of methods exist that allow assessing the energy-dependent attenuation in conventional systems. These methods consist of using two distinct spectra (kVp switching ordual source) or by discriminating low and high energy photons by means of stacking two detectors. Further improvements can be achievedby transitioning to direct-conversion technologies and counting-modedetection, which inherently exhibits a better signal-to-noise ratio.Further including energy discrimination, enables new applications,which are not feasible with dual-energy techniques, e.g. the possibility to discriminate K-edge features (contrast agents, e.g. Gadolinium) from the other contributions to the x-ray attenuation of a human body. The capability of providing energy-resolved information withtwo or more independent measurements is referred as Spectral CT.A new proprietary photon counting ASIC (ChromAIX) has been developedto provide high count-rate capabilities while offering energy discrimination. The ChromAIX consists of a pixel array with an isotropicpitch of 300 µm. Each pixel contains independent discriminators which enable the possibility to discretize incoming photons into a number of energy levels. Extensive electrical characterization has been carried out to assess the performance in terms of count-rate performance and noise. Observed rates exceeding 10 Mcps/pixel (Poissonian, mean incoming rates > 27 Mcps). The energy resolution is better than4.1 keV FWHM and has been shown to be consistent with simulations. Pile-up behaviour and count-rate dependency have also been evaluated. Electrical crosstalk among pixels in terms of count-rate activity and threshold position has been assessed and show no measureable influences across the array. X-ray tests have also been performed onsamples directly flip-chip bonded to CdTe and CZT crystals. The pulse shape and spectrum obtained from a 241Am source is consistent with simulations.

A fabric substrate is described for electronic textile with robust interwoven connections between the conductive yarns in it. The fabric's robustness, as a function of the electrical reliability of its conductive yarn connections, is shown to hold over large deformations.This fabric is then used to create an LED based photonic textile display. Finally, we show an example of an application that could make use of such a photonic textile system.

The proposed method simultaneously reconstructs activity and attenuation distribution of SPECT scans without usage of additional transmission scans. Moreover, in contrast to other approaches, it effectively prevents cross-talk artefacts by using a-priori atlas data and by labelling each organ with homogeneous attenuation values. The method generates a 3D-shape model of the patient and, in order to improve overall consistency between measured and estimated SPECT sinogram, modifications to the activity- and attenuation estimation are performed iteratively. Several reconstructions of patient and simulated SPECT data were investigated and reliable convergence behaviour as well as good agreement with reference images could be observed.

As a complement to maximum intensity projection (MIP) and direct volume rendering of the Hounsfield densities, a Hesse rendering can show the local curvature of structures rather than the densities. Color coding of the local curvatures, or simply of the eigenvalues of the local second derivatives, can provide an intuitive navigation device to blob-like anomalies in the lung such as pulmonary nodules and lymph nodes. Evaluation results based on the LIDC-IDRI lung image database indicate that the more radiologists agree on a certain anomaly to be a lung nodule, the brighter it appears in the Hesse rendering. The Hesse-rendering might thus be a complementary approach to classical computer aided detection approaches with explicit markers.

Basic electrowetting theory predicts that a continued increase in applied voltage will allow contact angle modulation to zero degrees. In practice, the effect of contact angle saturation has always been observed to limit the contact angle modulation, often only down to a contact angle of 60 to 70°. The physical origins of contact angle saturation have not yet been explained successfully and unequivocally. At best, scientists have produced multiple disconnected hypotheses (droplet ejection, charge injection, a thermodynamic limit, etc.) that do not satisfactorily hold for the large body of electrowetting experimental results. Herein we experimentally demonstrate that when using DC voltage, electrowetting contact angle saturation is invariant with electric field, contact line profile, interfacial tension, choice of non-polar insulating fluid, and type of polar conductive fluid or ionic content. The selected experiments were performed and designed using conventional electrowetting materials, without bias toward supporting a particular theory. Because the experimental results show such a strong invariance of saturation to multiple parameters, a new theory for electrowetting saturation is suggested: micro-droplet ejection through “Taylor saturation”. Although this work does not unequivocally prove what does cause contact angle saturation, it reveals what factors play a very limited or no role, and how dominant factors causing saturation may change with time of voltage application. This study thereby provides additional direction to the continued pursuit of a universal theory for electrowetting saturation.