605 research outputs found

    Willy Van Der Meeren’s Ieder Zijn Huis: Saving a Fragile Giant

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    The project for the renovation of the Willy Van Der Meeren apartment building known as Ieder Zijn Huis [“A House for Everyone”], in Brussels, raises a question that is crucial for the conservation of modern work using prefabrication techniques. The debate focuses on the original design and construction values, and above all on how best to keep them alive and contemporary despite the building's age and changing standards and techniques. In the wording of the renovation specifications, the project owner — the public company Beliris — laid stress on the importance of preserving the architectural qualities: “Given the building's importance in the architectural heritage, the renovation must reflect the original ideas of the designer, Willy Van Der Meeren”. The point of the call for tenders was to establish an approach for the work that conserves the structure's architectural principles in terms of appearance and structural articulation, while making renovated apartments available that meet today's standards. The architecture firm Origin decided to focus on the building's values and on the comfort and convenience of the accommodation, while pursuing further the conceptual direction taken by the original designer. This meant exploring all the building's architectural and structural aspects in order to successfully showcase its qualities

    Re-balancing problem for assembly lines: new mathematical model and exact solution method

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    The purpose of this study is to develop a new mathematical model and an exact solution method for an assembly line rebalancing problem. When an existing assembly line has to be adapted to a new production context, the line balancing, resources allocation and component management solutions have to be revised. The objective is to minimize the number of modifications to be done in the initial line in order to reduce the time and investment needed to meet new production requirements. The proposed model is evaluated via a computational experiment. The obtained results the efficacy of the proposed method

    Trajectory and smooth attractors for Cahn-Hilliard equations with inertial term

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    The paper is devoted to a modification of the classical Cahn-Hilliard equation proposed by some physicists. This modification is obtained by adding the second time derivative of the order parameter multiplied by an inertial coefficient which is usually small in comparison to the other physical constants. The main feature of this equation is the fact that even a globally bounded nonlinearity is "supercritical" in the case of two and three space dimensions. Thus the standard methods used for studying semilinear hyperbolic equations are not very effective in the present case. Nevertheless, we have recently proven the global existence and dissipativity of strong solutions in the 2D case (with a cubic controlled growth nonlinearity) and for the 3D case with small inertial coefficient and arbitrary growth rate of the nonlinearity. The present contribution studies the long-time behavior of rather weak (energy) solutions of that equation and it is a natural complement of the results of our previous papers. Namely, we prove here that the attractors for energy and strong solutions coincide for both the cases mentioned above. Thus, the energy solutions are asymptotically smooth. In addition, we show that the non-smooth part of any energy solution decays exponentially in time and deduce that the (smooth) exponential attractor for the strong solutions constructed previously is simultaneously the exponential attractor for the energy solutions as well

    The potential of permanent gullies in Europe as geomorphosites

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    Geotourism is a useful way to educate societies in the field of geomorphology and natural hazards. Geosites, including geomorphosites, represent the basis for the development of this type of tourism. This study describes twelve representative gully regions within nine European countries. The characteristics of 42 permanent gullies, gully systems and badland landscapes are presented and a geotouristic assessment of these gullies was made, based on scientific, educational, functional and touristic indicators. This assessment demonstrates a large difference between the selected gully sites, particularly with regard to functional and tourist values. The geotouristic potential of gullies is the highest in Italy and Spain and the lowest in Romania and Latvia. In some countries, permanent gullies are not regarded as geotouristic attractions at all, while in others they constitute a significant element of their tourism development strategy. Based on the analysis of scientific values of the gully sites, educational lessons to be learned were identified that are mainly related to i) gullies as a geological window, ii) present-day geomorphological processes, and iii) stages of historical gully erosion reflecting past human-environment interactions. These must be part of a broader strategy for the development of geotourism in gully regions. Gullies are potential geosites within existing or planned geoparks. Values of gullies for other forms of tourism (active, cultural, nature), should be also emphasized

    A Monte Carlo investigation of secondary electron emission from solid targets: spherical symmetry versus momentum conservation within the classical binary collision model

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    A Monte Carlo scheme is described where the secondary electron generation has been incorporated. The initial position of a secondary electron due to Fermi sea excitation is assumed to be where the inelastic collision took place, while the polar and azimuth angles of secondary electrons can be calculated in two different ways. The first one assumes a random direction of the secondary electrons, corresponding to the idea that slow secondary electrons should be generated with spherical symmetry. Such an approach violates momentum conservation. The second way of calculating the polar and azimuth angles of the secondary electrons takes into account the momentum conservation rules within the classical binary collision model. The aim of this paper is to compare the results of these two different approaches for the determination of the energy distribution of the secondary electrons emitted by solid targets.Comment: COSIRES2008. 9th Conference on Computer Simulation of Radiation Effects in Solids, Beijing, China, October 12-17, 200

    IGFBP-4 tumor and serum levels are increased across all stages of epithelial ovarian cancer

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    <p>Abstract</p> <p>Background</p> <p>We sought to identify candidate serum biomarkers for the detection and surveillance of EOC. Based on RNA-Seq transcriptome analysis of patient-derived tumors, highly expressed secreted proteins were identified using a bioinformatic approach.</p> <p>Methods</p> <p>RNA-Seq was used to quantify papillary serous ovarian cancer transcriptomes. Paired end sequencing of 22 flash frozen tumors was performed. Sequence alignments were processed with the program ELAND, expression levels with ERANGE and then bioinformatically screened for secreted protein signatures. Serum samples from women with benign and malignant pelvic masses and serial samples from women during chemotherapy regimens were measured for IGFBP-4 by ELISA. Student's t Test, ANOVA, and ROC curves were used for statistical analysis.</p> <p>Results</p> <p>Insulin-like growth factor binding protein (IGFBP-4) was consistently present in the top 7.5% of all expressed genes in all tumor samples. We then screened serum samples to determine if increased tumor expression correlated with serum expression. In an initial discovery set of 21 samples, IGFBP-4 levels were found to be elevated in patients, including those with early stage disease and normal CA125 levels. In a larger and independent validation set (82 controls, 78 cases), IGFBP-4 levels were significantly increased (p < 5 × 10<sup>-5</sup>). IGFBP-4 levels were ~3× greater in women with malignant pelvic masses compared to women with benign masses. ROC sensitivity was 73% at 93% specificity (AUC 0.816). In women receiving chemotherapy, average IGFBP-4 levels were below the ROC-determined threshold and lower in NED patients compared to AWD patients.</p> <p>Conclusions</p> <p>This study, the first to our knowledge to use RNA-Seq for biomarker discovery, identified IGFBP-4 as overexpressed in ovarian cancer patients. Beyond this, these studies identified two additional intriguing findings. First, IGFBP-4 can be elevated in early stage disease without elevated CA125. Second, IGFBP-4 levels are significantly elevated with malignant versus benign disease. These findings provide the rationale for future validation studies.</p

    Longtime behavior of nonlocal Cahn-Hilliard equations

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    Here we consider the nonlocal Cahn-Hilliard equation with constant mobility in a bounded domain. We prove that the associated dynamical system has an exponential attractor, provided that the potential is regular. In order to do that a crucial step is showing the eventual boundedness of the order parameter uniformly with respect to the initial datum. This is obtained through an Alikakos-Moser type argument. We establish a similar result for the viscous nonlocal Cahn-Hilliard equation with singular (e.g., logarithmic) potential. In this case the validity of the so-called separation property is crucial. We also discuss the convergence of a solution to a single stationary state. The separation property in the nonviscous case is known to hold when the mobility degenerates at the pure phases in a proper way and the potential is of logarithmic type. Thus, the existence of an exponential attractor can be proven in this case as well

    Application of RNA-Seq transcriptome analysis: CD151 is an Invasion/Migration target in all stages of epithelial ovarian cancer

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    <p>Abstract</p> <p>Background</p> <p>RNA-Seq allows a theoretically unbiased analysis of both genome-wide transcription levels and mutation status of a tumor. Using this technique we sought to identify novel candidate therapeutic targets expressed in epithelial ovarian cancer (EOC).</p> <p>Methods</p> <p>Specifically, we sought candidate invasion/migration targets based on expression levels across all tumors, novelty of expression in EOC, and known function. RNA-Seq analysis revealed the high expression of CD151, a transmembrane protein, across all stages of EOC. Expression was confirmed at both the mRNA and protein levels using RT-PCR and immunohistochemical staining, respectively.</p> <p>Results</p> <p>In both EOC tumors and normal ovarian surface epithelial cells we demonstrated CD151 to be localized to the membrane and cell-cell junctions in patient-derived and established EOC cell lines. We next evaluated its role in EOC dissemination using two ovarian cancer-derived cell lines with differential levels of CD151 expression. Targeted antibody-mediated and siRNA inhibition or loss of CD151 in SKOV3 and OVCAR5 cell lines effectively inhibited their migration and invasion.</p> <p>Conclusion</p> <p>Taken together, these findings provide the first proof-of-principle demonstration for a next generation sequencing approach to identifying candidate therapeutic targets and reveal CD151 to play a role in EOC dissemination.</p

    Driving the atom by atomic fluorescence: analytic results for the power and noise spectra

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    We study how the spectral properties of resonance fluorescence propagate through a two-atom system. Within the weak-driving-field approximation we find that, as we go from one atom to the next, the power spectrum exhibits both sub-natural linewidth narrowing and large asymmetries while the spectrum of squeezing narrows but remains otherwise unchanged. Analytical results for the observed spectral features of the fluorescence are provided and their origin is thoroughly discussed.Comment: 13 pages, 5 figures; to be published in Phys. Rev. A Changed title and conten

    Validation of the Quantitative Checklist for Autism in Toddlers in an Italian Clinical Sample of Young Children With Autism and Other Developmental Disorders.

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    Background: The Quantitative Checklist for Autism in Toddlers (Q-CHAT) is parent-report screening questionnaire for detecting threshold and sub-threshold autistic features in toddlers. The Q-CHAT is a dimensional measure normally distributed in the general population sample and is able to differentiate between a group of children with a diagnosis of autism and unselected toddlers. Objectives: We aim to investigate the psychometric properties, score distribution, and external validity of the Q-CHAT in an Italian clinical sample of young children with autism versus children with developmental delay and typically developing children. Method: N = 126 typically developing children (TD), n = 139 children with autism, and n = 50 children presenting developmental delay (DD) were administered the Q-CHAT. Standardized measures of cognitive functions, language, and behaviors were also obtained. Results: The Q-CHAT scores were normally distributed and demonstrated adequate internal consistency and good item to total score correlations. The mean Q-CHAT score in the autism group was significantly higher than those found in the DD sample and TD children. No difference on the mean Q-CHAT score between DD and TD children was found. The accuracy of the Q-CHAT to discriminate between autism and TD was very good. Two different cut-points (27 and 31, respectively) maximized sensitivity and specificity for autism versus TD and DD, respectively. Finally, higher Q-CHAT scores were correlated with lower language and social communication skills. Conclusions: In clinical settings, the Q-CHAT demonstrated good psychometric properties and external validity to discriminate autism children not just from children with typical development but also from children with developmental delay
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