Rheological and mechanical performance evaluation of high performance mortar based natural pozzolan

This paper presents an experimental study on the rheological and mechanical properties of High Performance Mortar (HPM) based on natural pozzolan (NP). The specific surface BET of NP was 370 m²/kg used with different contents by weight of cement (5, 10, 15 and 20%). Two (w/b) water-binder ratios (0.35and 0.40) were used, the dosage of Superplasticizer (Sp) was kept constant (0.32 by weight of cement). The experimental results show that rheological properties of HPM increased with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both yield stress and plastic viscosity of mixtures.The mechanical characteristics were improved with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both compressive strength. The optimal percentage substitution was 15% of NP, reducing CO2 emission by 20% for each cubic meter of mortar production

Rheological and mechanical performance evaluation of high performance mortar based natural pozzolan

This paper presents an experimental study on the rheological and mechanical properties of High Performance Mortar (HPM) based on natural pozzolan (NP). The specific surface BET of NP was 370 m²/kg used with different contents by weight of cement (5, 10, 15 and 20%). Two (w/b) water-binder ratios (0.35and 0.40) were used, the dosage of Superplasticizer (Sp) was kept constant (0.32 by weight of cement). The experimental results show that rheological properties of HPM increased with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both yield stress and plastic viscosity of mixtures.The mechanical characteristics were improved with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both compressive strength. The optimal percentage substitution was 15% of NP, reducing CO2 emission by 20% for each cubic meter of mortar production

VDNA: The virtual DNA plug-in for VMD

Summary: The DNA inter base pair step parameters (Tilt, Roll, Twist, Shift, Slide, Rise) are a standard internal coordinate representation of DNA. In the absence of bend and shear, it is relatively easy to mentally visualize how Twist and Rise generate the familiar double helix. More complex structures do not readily yield to such intuition. For this reason, we developed a plug-in for VMD that accepts a set of mathematical expressions as input and generates a coarse-grained model of DNA as output. This feature of VDNA appears to provide a unique approach to DNA modeling. Predefined expressions include: linear, sheared, bent and circular DNA, and models of the nucleosome superhelix, chromatin, thermal motion and nucleosome unwrapping

High performance Peer-to-Peer distributed computing with application to obstacle problem

International audienceThis paper deals with high performance Peer-to-Peer computing applications. We concentrate on the solution of large scale numerical simulation problems via distributed iterative methods. We present the current version of an environment that allows direct communication between peers. This environment is based on a self-adaptive communication protocol. The protocol configures itself automatically and dynamically in function of application requirements like scheme of computation and elements of context like topology by choosing the most appropriate communication mode between peers. A first series of computational experiments is presented and analyzed for the obstacle problem

Lignin-Depolymerisation via UV-Photolysis and Titanium Dioxide Photocatalysis

Today, more than 70 million tons of lignin are produced by the pulp and paper industry every year. However, the utilization of lignin as a source for chemical synthesis is still limited due to the complex and heterogeneous lignin structure. The purpose of this study was a selective photodegradation of industrially available kraft lignin in order to obtain appropriate fragments and building block chemicals for further utilization, e.g. polymerization. Thus, kraft lignin obtained from soft wood black liquor by acidification was dissolved in sodium hydroxide and irradiated at a wavelength of 254 nm with and without the presence of titanium dioxide in various concentrations. Analyses of the irradiated products via SEC showed decreasing molar masses and decreasing polydispersity indices over time. At the end of the irradiation period the lignin was depolymerised to form fragments as small as the lignin monomers. TOC analyses showed minimal mineralisation due to the depolymerisation process

3D-DART: a DNA structure modelling server

There is a growing interest in structural studies of DNA by both experimental and computational approaches. Often, 3D-structural models of DNA are required, for instance, to serve as templates for homology modeling, as starting structures for macro-molecular docking or as scaffold for NMR structure calculations. The conformational adaptability of DNA when binding to a protein is often an important factor and at the same time a limitation in such studies. As a response to the demand for 3D-structural models reflecting the intrinsic plasticity of DNA we present the 3D-DART server (3DNA-Driven DNA Analysis and Rebuilding Tool). The server provides an easy interface to a powerful collection of tools for the generation of DNA-structural models in custom conformations. The computational engine beyond the server makes use of the 3DNA software suite together with a collection of home-written python scripts. The server is freely available at http://haddock.chem.uu.nl/dna without any login requirement

The Pitfalls of Necessary Assignments

It has been shown that, finding necessary assignments during a search process, such as Automatic Test Pattern Generation (ATPG) process, can significantly improve its search performance. The techniques to find necessary assignments include static learning, dynamic learning, and recursive learning. All these techniques did improve ATPG performance. However, in our experience with real circuits, we found that necessary assignments can create unnecessary requirements in an ATPG process. Sometimes, these unnecessary requirements are not justifiable such that a testable fault may be mistaken as untestable

The Pitfalls of Necessary Assignments

It has been shown that, finding necessary assignments during a search process, such as Automatic Test Pattern Generation (ATPG) process, can significantly improve its search performance. The techniques to find necessary assignments include static learning, dynamic learning, and recursive learning. All these techniques did improve ATPG performance. However, in our experience with real circuits, we found that necessary assignments can create unnecessary requirements in an ATPG process. Sometimes, these unnecessary requirements are not justifiable such that a testable fault may be mistaken as untestable

Olaparib for metastatic breast cancer in patients with a germline BRCA mutation

BACKGROUND Olaparib is an oral poly(adenosine diphosphate-ribose) polymerase inhibitor that has promising antitumor activity in patients with metastatic breast cancer and a germline BRCA mutation. METHODS We conducted a randomized, open-label, phase 3 trial in which olaparib monotherapy was compared with standard therapy in patients with a germline BRCA mutation and human epidermal growth factor receptor type 2 (HER2)-negative metastatic breast cancer who had received no more than two previous chemotherapy regimens for metastatic disease. Patients were randomly assigned, in a 2: 1 ratio, to receive olaparib tablets (300 mg twice daily) or standard therapy with single-agent chemotherapy of the physician's choice (capecitabine, eribulin, or vinorelbine in 21-day cycles). The primary end point was progression-free survival, which was assessed by blinded independent central review and was analyzed on an intention-to-treat basis. RESULTS Of the 302 patients who underwent randomization, 205 were assigned to receive olaparib and 97 were assigned to receive standard therapy. Median progression-free survival was significantly longer in the olaparib group than in the standardtherapy group (7.0 months vs. 4.2 months; hazard ratio for disease progression or death, 0.58; 95% confidence interval, 0.43 to 0.80; P<0.001). The response rate was 59.9% in the olaparib group and 28.8% in the standard-therapy group. The rate of grade 3 or higher adverse events was 36.6% in the olaparib group and 50.5% in the standard-therapy group, and the rate of treatment discontinuation due to toxic effects was 4.9% and 7.7%, respectively. CONCLUSIONS Among patients with HER2-negative metastatic breast cancer and a germline BRCA mutation, olaparib monotherapy provided a significant benefit over standard therapy; median progression-free survival was 2.8 months longer and the risk of disease progression or death was 42% lower with olaparib monotherapy than with standard therapy. (Funded by AstraZeneca; OlympiAD ClinicalTrials.gov number, NCT02000622.

Dual role of immune cells in the testis: protective or pathogenic for germ cells?

The purpose of this review is to describe how the immune cells present in the testis interact with the germinal epithelium contributing to survival or apoptosis of germ cells (GCs). Physiologically, the immunosuppressor testicular microenvironment protects GCs from immune attack, whereas in inflammatory conditions, tolerance is disrupted and immune cells and their mediators respond to GC self antigens, inducing damage of the germinal epithelium. Considering that experimental models of autoimmune orchitis have clarified the local immune mechanisms by which protection of the testis is compromised, we described the following topics in the testis of normal and orchitic rats: (1) cell adhesion molecule expression of seminiferous tubule specialized junctions and modulation of blood-testis barrier permeability by cytokines (2) phenotypic and functional characteristics of testicular dendritic cells, macrophages, effector and regulatory T cells and mast cells and (3) effects of pro-inflammatory cytokines (TNF-α, IL-6 and FasL) and the nitric oxide-nitric oxide synthase system on GC apoptosis.Fil: Pérez, Cecilia Valeria. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Theas, Maria Susana. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Jacobo, Patricia Verónica. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Jarazo Dietrich, Sabrina Soledad. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Guazzone, Vanesa Anabella. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Lustig, Livia. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentin