Thermal conductivity of gypsum plasterboard beyond dehydration and its correlation with the pore structure

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.Gypsum plasterboard is a material used in the building industry for its low weight (porosity 50-65%) and its high resistance to fire due to the endothermic dehydration taking place between 150 and 200°C. Its thermal conductivity which is a decisive thermal property regarding reaction to fire drops by 50% of its initial value after dehydration due to the loss of water (20 mass %) but starts to rise again with rising temperature and reaches its initial value around 750°C. The present study shows that this rise is not due to the increasing radiative or conductive heat transfer but to changes in the bimodal pore structure which leaves the overall structural dimensions nearly unchanged (dilatation of around 2%). Different methods such as mercury intrusion porosimetry, scanning electron microscopy and in-situ X-ray diffraction up to 1000°C were carried out to investigate the correlation between pore structure and thermal conductivity of this material.dc201

Testing the theory of immune selection in cancers that break the rules of transplantation

Modification of cancer cells likely to reduce their immunogenicity, including loss or down-regulation of MHC molecules, is now well documented and has become the main support for the concept of immune surveillance. The evidence that these modifications, in fact, result from selection by the immune system is less clear, since the possibility that they may result from reorganized metabolism associated with proliferation or from cell de-differentiation remains. Here, we (a) survey old and new transplantation experiments that test the possibility of selection and (b) survey how transmissible tumours of dogs and Tasmanian devils provide naturally evolved tests of immune surveillance

The Evolving Transcriptome of Head and Neck Squamous Cell Carcinoma: A Systematic Review

BACKGROUND: Numerous studies were performed to illuminate mechanisms of tumorigenesis and metastases from gene expression profiles of Head and Neck Squamous Cell Carcinoma (HNSCC). The objective of this review is to conduct a network-based meta-analysis to identify the underlying biological signatures of the HNSCC transcriptome. METHODS AND FINDINGS: We included 63 HNSCC transcriptomic studies into three specific categories of comparisons: Pre, premalignant lesions v.s. normal; TvN, primary tumors v.s. normal; and Meta, metastatic or invasive v.s. primary tumors. Reported genes extracted from the literature were systematically analyzed. Participation of differential gene activities across three progressive stages deciphered the evolving nature of HNSCC. In total, 1442 genes were verified, i.e. reported at least twice, with ECM1, EMP1, CXCL10 and POSTN shown to be highly reported across all three stages. Knowledge-based networks of the HNSCC transcriptome were constructed, demonstrating integrin signaling and antigen presentation pathways as highly enriched. Notably, functional estimates derived from topological characteristics of integrin signaling networks identified such important genes as ITGA3 and ITGA5, which were supported by findings of invasiveness in vitro. Moreover, we computed genome-wide probabilities of reporting differential gene activities for the Pre, TvN, and Meta stages, respectively. Results highlighted chromosomal regions of 6p21, 19p13 and 19q13, where genomic alterations were shown to be correlated with the nodal status of HNSCC. CONCLUSIONS: By means of a systems-biology approach via network-based meta-analyses, we provided a deeper insight into the evolving nature of the HNSCC transcriptome. Enriched canonical signaling pathways, hot-spots of transcriptional profiles across the genome, as well as topologically significant genes derived from network analyses were highlighted for each of the three progressive stages, Pre, TvN, and Meta, respectively

IFN-γ Rα Is a Key Determinant of CD8+ T Cell-Mediated Tumor Elimination or Tumor Escape and Relapse in FVB Mouse

During the past decade, the dual function of the immune system in tumor inhibition and tumor progression has become appreciated. We have previously reported that neu-specific T cells can induce rejection of neu positive mouse mammary carcinoma (MMC) and also facilitate tumor relapse by inducing neu antigen loss and epithelial to mesenchymal transition (EMT). Here, we sought to determine the mechanism by which CD8+ T cells either eliminate the tumor, or maintain tumor cells in a dormant state and eventually facilitate tumor relapse. We show that tumor cells that express high levels of IFN-γ Rα are eliminated by CD8+ T cells. In contrast, tumor cells that express low levels of IFN-γ Rα do not die but remain dormant and quiescent in the presence of IFN-γ producing CD8+ T cells until they hide themselves from the adaptive immune system by losing the tumor antigen, neu. Relapsed tumor cells show CD44+CD24- phenotype with higher rates of tumorigenesis, in vivo. Acquisition of CD44+CD24- phenotype in relapsed tumors was not solely due to Darwinian selection. Our data suggest that tumor cells control the outcome of tumor immune surveillance through modulation of the expression of IFN-γ Rα

An integrated drug repurposing strategy for the rapid identification of potential SARS-CoV-2 viral inhibitors

The Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). The virus has rapidly spread in humans, causing the ongoing Coronavirus pandemic. Recent studies have shown that, similarly to SARS-CoV, SARS-CoV-2 utilises the Spike glycoprotein on the envelope to recognise and bind the human receptor ACE2. This event initiates the fusion of viral and host cell membranes and then the viral entry into the host cell. Despite several ongoing clinical studies, there are currently no approved vaccines or drugs that specifically target SARS-CoV-2. Until an effective vaccine is available, repurposing FDA approved drugs could significantly shorten the time and reduce the cost compared to de novo drug discovery. In this study we attempted to overcome the limitation of in silico virtual screening by applying a robust in silico drug repurposing strategy. We combined and integrated docking simulations, with molecular dynamics (MD), Supervised MD (SuMD) and Steered MD (SMD) simulations to identify a Spike protein – ACE2 interaction inhibitor. Our data showed that Simeprevir and Lumacaftor bind the receptor-binding domain of the Spike protein with high affinity and prevent ACE2 interaction

Exporting and labor demand : micro-level evidence from Germany

It is widely believed that globalization affcts the extent of employment and wage responses to economic shocks. To provide evidence for this, we analyze the effect of firms' exporting behavior on the elasticity of labor demand. Using rich, German administrative linked employer-employee panel data from 1996 to 2008, we explicitly control for self-selection into exporting and endogeneity concerns. In line with our theoretical model, we find that exporting at both the intensive and extensive margins significantly increases the (absolute value of the) unconditional own-wage labor demand elasticity. This is not only true for the average worker, but also for different skill groups. For the median firm, the elasticity is three-quarters higher when comparing exporting to nonexporting firms

Tumor immunosurveillance in human cancers

Until now, the anatomic extent of tumor (TNM classification) has been by far the most important factor to predict the prognosis of colorectal cancer patients. However, in recent years, data collected from large cohorts of human cancers demonstrated that the immune contexture of the primary tumors is an essential prognostic factor for patients’ disease-free and overall survival. Tumoral and immunological markers predicted by systems biology methods are involved in the shaping of an efficient immune reaction and can serve as targets for novel therapeutic approaches. Global analysis of tumor microenvironment showed that the nature, the functional orientation, the density, and the location of adaptive immune cells within distinct tumor regions influence the risk of relapse events. The density and the immune cell location within the tumor have a prognostic value that is superior to the TNM classification, and tumor invasion is statistically dependent on the host-immune reaction. Thus, the strength of the immune reaction could advance our understanding of cancer evolution and have important consequences in clinical practice

Selective blockade of interferon-α and -β reveals their non-redundant functions in a mouse model of West Nile virus infection

Although type I interferons (IFNs) were first described almost 60 years ago, the ability to monitor and modulate the functional activities of the individual IFN subtypes that comprise this family has been hindered by a lack of reagents. The major type I IFNs, IFN-β and the multiple subtypes of IFN-α, are expressed widely and induce their effects on cells by interacting with a shared heterodimeric receptor (IFNAR). In the mouse, the physiologic actions of IFN-α and IFN-β have been defined using polyclonal anti-type I IFN sera, by targeting IFNAR using monoclonal antibodies or knockout mice, or using Ifnb-/- mice. However, the corresponding analysis of IFN-α has been difficult because of its polygenic nature. Herein, we describe two monoclonal antibodies (mAbs) that differentially neutralize murine IFN-β or multiple subtypes of murine IFN-α. Using these mAbs, we distinguish specific contributions of IFN-β versus IFN-α in restricting viral pathogenesis and identify IFN-α as the key mediator of the antiviral response in mice infected with West Nile virus. This study thus suggests the utility of these new reagents in dissecting the antiviral and immunomodulatory roles of IFN-β versus IFN-α in murine models of infection, immunity, and autoimmunity