pinecone/core-2020-05-10-deduplication huggingface dataset:
Tuning of Collagen Scaffold Properties Modulates Embedded Endothelial Cell Regulatory Phenotype in Repair of Vascular Injuries In Vivo

Perivascularly implanted matrix embedded endothelial cells (MEECs) are potent regulators of inflammation and intimal hyperplasia following vascular injuries. Endothelial cells (ECs) in collagen scaffolds adopt a reparative phenotype with significant therapeutic potential. Although the biology of MEECs is increasingly understood, tuning of scaffold properties to control cell-substrate interactions is less well-studied. It is hypothesized that modulating scaffold degradation would change EC phenotype. Scaffolds with differential degradation are prepared by cross-linking and predegradation. Vascular injury increases degradation and the presence of MEECs retards injury-mediated degradation. MEECs respond to differential scaffold properties with altered viability in vivo, suppressed smooth muscle cell (SMC) proliferation in vitro, and altered interleukin-6 and matrix metalloproteinase-9 expression. When implanted perivascularly to a murine carotid wire injury, tuned scaffolds change MEEC effects on vascular repair and inflammation. Live animal imaging enables real-time tracking of cell viability, inflammation, and scaffold degradation, affording an unprecedented understanding of interactions between cells, substrate, and tissue. MEEC-treated injuries improve endothelialization and reduce SMC hyperplasia over 14 d. These data demonstrate the potent role material design plays in tuning MEEC efficacy in vivo, with implications for the design of clinical therapies.National Institutes of Health (U.S.) (Grant R01 GM 49039
Mixing dynamics in bubbling fluidized beds

Solids mixing affects thermal and concentration gradients in fluidized bed reactors and is, therefore, critical to their performance. Despite substantial effort over the past decades, understanding of solids mixing continues to be lacking because of technical limitations of diagnostics in large pilot and commercial‐scale reactors. This study is focused on investigating mixing dynamics and their dependence on operating conditions using computational fluid dynamics simulations. Toward this end, fine‐grid 3D simulations are conducted for the bubbling fluidization of three distinct Geldart B particles (1.15 mm LLDPE, 0.50 mm glass, and 0.29 mm alumina) at superficial gas velocities U/Umf = 2–4 in a pilot‐scale 50 cm diameter bed. The Two‐Fluid Model (TFM) is employed to describe the solids motion efficiently while bubbles are detected and tracked using MS3DATA. Detailed statistics of the flow‐field in and around bubbles are computed and used to describe bubble‐induced solids micromixing: solids upflow driven in the nose and wake regions while downflow along the bubble walls. Further, within these regions, the hydrodynamics are dependent only on particle and bubble characteristics, and relatively independent of the global operating conditions. Based on this finding, a predictive mechanistic, analytical model is developed which integrates bubble‐induced micromixing contributions over their size and spatial distributions to describe the gross solids circulation within the fluidized bed. Finally, it is shown that solids mixing is affected adversely in the presence of gas bypass, or throughflow, particularly in the fluidization of heavier particles. This is because of inefficient gas solids contacting as 30–50% of the superficial gas flow escapes with 2–3× shorter residence time through the bed. This is one of the first large‐scale studies where both the gas (bubble) and solids motion, and their interaction, are investigated in detail and the developed framework is useful for predicting solids mixing in large‐scale reactors as well as for analyzing mixing dynamics in complex reactive particulate systems.British Petroleum CompanyNational Energy Technology Laboratory (U.S.)United States. Department of Energ
Frequency-Swept Integrated Solid Effect

The efficiency of continuous wave dynamic nuclear polarization (DNP) experiments decreases at the high magnetic fields used in contemporary high-resolution NMR applications. To recover the expected signal enhancements from DNP, we explored time domain experiments such as NOVEL which matches the electron Rabi frequency to the nuclear Larmor frequency to mediate polarization transfer. However, satisfying this matching condition at high frequencies is technically demanding. As an alternative we report here frequency-swept integrated solid effect (FS-ISE) experiments that allow low power sweeps of the exciting microwave frequencies to constructively integrate the negative and positive polarizations of the solid effect, thereby producing a polarization efficiency comparable to (±10 % difference) NOVEL. Finally, the microwave frequency modulation results in field profiles that exhibit new features that we coin the “stretched” solid effect.National Institute of Biomedical Imaging and Bioengineering (U.S.) (Grant EB-002804)National Institute of Biomedical Imaging and Bioengineering (U.S.) (Grant EB-002026)National Institute of General Medical Sciences (U.S.) (Grant GM095843
Enhancing expanded poly(tetrafluoroethylene) (ePTFE) for biomaterials applications

Poly(tetrafluoroethylene) (PTFE), a fully fluorinated linear thermoplastic polymer, and in particular the porous form expanded PTFE (ePTFE) has found widespread use in biomaterials application due to its properties of high toughness, non-adhesiveness and hydrophobicity. While it performs ideally for many applications, some challenges have been identified for its use in small diameter vascular grafts and as a tissue space-filler for cosmetic reconstructions where the implant interfaces with bone. For these applications modification of the surface of ePTFE has been investigated as a means to enhance its performance. This review will focus on the applications listed above and will detail methods of evaluating the biological response, methods used to enhance the surface properties of ePTFE, and how the modified materials have performed in their intended applications. This review will focus on work published from 2004 onwards.Griffith Health, School of Medical ScienceFull Tex
Solubility factors as screening tools of biodegradable toughening agents of polylactide

Changes in the thermomechanical properties of polylactide (PLA) plasticized by two biodegradable and biobased molecules, Polysorb ID37 (PID37) and squalene, were compared to formulations with petroleum-based plasticizers, namely, acetyl tributyl citrate, poly(ethylene glycol) 400, and dioctyl adipate (DOA). The solubility parameters of the additives were calculated and were related to the plasticization behaviors. PID37 proved to be miscible with PLA because of its polar functions and short alkyl groups. It decreased the PLA glass-transition temperature (Tg) and increased in ductility when Tg approached room temperature. Squalene had a low miscibility because of the absence of polar groups. Tg was not depressed. Ductility improvements were nevertheless reached because the immiscible inclusions efficiently induced crazing by the distribution of stress concentration points all over the material; this delayed failure. The maximum elongations at break were 60% for squalene, 400% for DOA, and 500% for PID37. The solubility factors were, thus, an efficient prediction tool for the plasticizing behavio
Development of a novel process for the production of man-made cellulosic fibers from ionic liquid solution

This study presents the development of a novel process for producing man-made cellulosic fibers from an ionic liquid solution, the so called Ioncell-F process. It examines the full production chain from efficient dissolution of cellulose in ionic liquid to the suitability of the spun fibers for textile applications. A dry-jet wet spinning process consisting of the extrusion of a polymer solution at mild temperature through a multi-filament spinneret into an aqueous coagulation bath via an air gap was employed for the regeneration of cellulose into filaments. For preparation of the spinning dopes, 1-ethyl-3-methylimidazolium acetate and 1,5-diazabicyclo[4.3.0]non-5-enium acetate were used as solvents for different commercial dissolving pulps.
Both ionic liquids showed an excellent capability in dissolving cellulose at mild conditions. Minor cellulose depolymerization was obtained at a temperature below 85 ºC with a low shearing rate. The intrinsic properties of the dissolved raw material, such as the degree of polymerization and molar mass distribution, exhibited a significant influence on the viscoelastic properties of the resulting polymer solution, and were monitored by oscillatory shear rheology and extensional rheology. The viscoelastic properties of the cellulose/ionic solution played a key role in determining the so called "spinning window" required to achieve optimal spinnability.
The tested 1-ethyl-3-methylimidazolium acetate/cellulose solution showed poor processing ability, while the 1,5-diazabicyclo[4.3.0]non-5-enium acetate/cellulose solution revealed effective spinning capability, resulting in the production of high-tenacity cellulosic staple fibers.
The fundamental spinning concepts were investigated and contributed to the determination of the spinning window. Cellulosic fibers, covering a wide spectrum of structural and mechanical properties, were manufactured by varying the applied stretch of the extruded filaments.
Ioncell fibers belong to the category of Lyocell fibers, provided that they are produced commercially, and display appropriate structural and mechanical behavior to be converted into yarn, and subsequently converted to knitted and woven fabrics. The excellent performance of the Ioncell spun yarn during the knitting and weaving process confirmed the competitive quality of the yarn and its suitability for the production of apparel. The future of this technology as an alternative to the viscose and NMMO-based Lyocell processes is promising, based on the development of a viable solvent-recovery step
Dynamic rheological behavior of poly(ether ketone ketone) from solid state to melt state

High performance thermoplastic poly(ether ketone ketone) (PEKK) polymers with various meta phenyl links ratio were investigated by dynamical mechanical analysis. Analyses were carried out in a wide range of temperature from solid state (torsion rectangular mode) to the melt state (torsion parallel plates mode) as function of thermal history and environmental conditions. In the solid state, this study was focused on the secondary relaxations in the vitreous state. A complementary investigation conducted with different poly(aryl ether ketones) allowed us to propose a molecular interpretation of PEKK sub-vitreous relaxations. In the molten state, storage modulus (G0), loss modulus (G00), storage viscosity (h0), and loss viscosity (h00) were studied to determine zero shear-rate viscosity (h0) and thermal activation energy Ea. Master curves were built and the shift factor aT was determined. Thermal activation energies were extracted from an Arrhenius model on the shift factor temperature’s dependency. Finally, Ea and h0 were determined thanks to the dynamic viscosity fit with Cross model and Cole–Cole representatio
Influence of silver nanowires on thermal and electrical behaviors of a poly(epoxy) coating for aeronautical application

Thermal and electrical behaviors of a poly(epoxy) coating with high electrical conductivity used for aeronautic applications are investigated. The poly(epoxy) used is designed for resin transfer molding (RTM) applications, it have a low viscosity at room temperature (around 1 Pa s) and a high Tg (>160°C). This study details the influence of silver nanowires with a high aspect ratio, on the thermal behavior such as the relative degree of reaction α and the kinetics parameters thanks to dynamic and isothermal differential scanning calorimetry. Conductivity measurements of surface and volume have permitted to determine a very low percolation threshold at around 0.7% in volume. The value of electrical conductivity above the percolation threshold is upper than 102 S m−1 and the lowest surface resistivity was measured around 13 mΩ sq−1 both for 8% in volume of AgNWs. This kind of coating has a great interest for lightning strike protection of aircraft parts due to the high electrical conductivity obtained with a low overweight
N-(INDAZOLYL)BENZAMIDO DERIVATIVES AS CDK1 INHIBITORS: DESIGN, SYNTHESIS, BIOLOGICAL ACTIVITY, AND MOLECULAR DOCKING STUDIES

A series of N-1H-indazole-1-carboxamides have been synthesized and their effects on both CDK1/cyclin B and K-562 (human chronic myelogenus leukemia) cell line were evaluated. Using a computational model we have observed that all the most active compound 9e,f,i-n exhibited the same binding mode of Purvanalol A in the ATP-binding cleft. Although they were able to moderately inhibit the leukemic cell line K-562, and to show inhibitory activity against the Cdc2-Cyclin B kinase in the low micromolar range, they resulted non cytotoxic against HuDe (IZSL), primary cell cultures from human derm. These preliminary results are quite encouraging in view of the low toxicity showed by the above mentioned compounds
Design of a FI xed-order RST controller for interval systems : application to the control of piezoelectric actuators.

International audienceThis paper presents a technique to design a robust polynomial RST controller for parametric uncertain systems. The uncertain parameters are assumed to be bounded by intervals. The computation of the controller is addressed by introducing the interval arithmetic. The controller synthesis is formulated as a set inversion problem that can be solved using the SIVIA algorithm. The proposed method is afterwards applied to design a robust controller for a piezoelectric microactuator. The experimental results show the e ciency of the proposed method. Finally, a ne stability analysis is performed to analytically prove the robustness of the designed controller
RNA-Peptide nanoplexes drug DNA damage pathways in high-grade serous ovarian tumors

DNA damaging chemotherapy is a cornerstone of current front‐line treatments for advanced ovarian cancer (OC). Despite the fact that a majority of these patients initially respond to therapy, most will relapse with chemo‐resistant disease; therefore, adjuvant treatments that synergize with DNA‐damaging chemotherapy could improve treatment outcomes and survival in patients with this deadly disease. Here, we report the development of a nanoscale peptide‐nucleic acid complex that facilitates tumor‐specific RNA interference therapy to chemosensitize advanced ovarian tumors to frontline platinum/taxane therapy. We found that the nanoplex‐mediated silencing of the protein kinase, MK2, profoundly sensitized mouse models of high‐grade serous OC to cytotoxic chemotherapy by blocking p38/MK2‐dependent cell cycle checkpoint maintenance. Combined RNAi therapy improved overall survival by 37% compared with platinum/taxane chemotherapy alone and decreased metastatic spread to the lungs without observable toxic side effects. These findings suggest (a) that peptide nanoplexes can serve as safe and effective delivery vectors for siRNA and (b) that combined inhibition of MK2 could improve treatment outcomes in patients currently receiving frontline chemotherapy for advanced OC.National Institutes of Health (U.S.) (Grant R01-ES015339)National Institute of Biomedical Imaging and Bioengineering (U.S.) (Grant 1F32EB017614)National Science Foundation (U.S.) (Grant GFRP 1122374)National Cancer Institute (U.S.) (Grant P30-CA14051)National Science Foundation (U.S.) (Grant DMR-0819762
Discretionary power of project managers in knowledge intensive firms and gender issues

The scarcity of   women among the highly qualified professionals in business-to-business information and communication technologies (ICT), either in Europe andor in North America, has been noted as recently as the late 1990’s (Panteli, Stack, Atkinson, & Ramsay, 1999). The organization and management of work in such organizations firms is typically project-based. This   has many consequences, including: long working hours with fierce resistance to shorter hoursany reduction, unpaid overtime, high management expectations of employee flexibility to meet unanticipated client demands, and the need for employees to negotiate flexible work arrangements on a case-by-cases basis with a project manager who often has much discretion on whether to accommodate such requests.   We found that women are particularly disadvantaged in such a system, which could partly explain their under-representation in such jobs
Regularity of the Level Set Flow

We showed earlier that the level set function of a monotonic advancing front is twice differentiable everywhere with bounded second derivative and satisfies the equation classically. We show here that the second derivative is continuous if and only if the flow has a single singular time where it becomes extinct and the singular set consists of a closed C[superscript 1] manifold with cylindrical singularities. © 2017 Wiley Periodicals, Inc.National Science Foundation (U.S.) (Grant DMS 1404540)National Science Foundation (U.S.) (Grant DMS 1206827
A frequency-domain approach to the analysis of stability and bifurcations in nonlinear systems described by differential-algebraic equations

A general numerical technique is proposed for the assessment of the stability of periodic solutions and the determination of bifurcations for limit cycles in autonomous nonlinear systems represented by ordinary differential equations in the differential-algebraic form. The method is based on the harmonic balance technique, and exploits the same Jacobian matrix of the nonlinear system used in the Newton iterative numerical solution of the harmonic balance equations for the determination of the periodic steady-state. To demonstrate the approach, it is applied to the determination of the bifurcation curves in the parameters' space of Chua's circuit with cubic nonlinearity, and to study the dynamics of the limit cycle of a Colpitts oscillato
Tracking Conformational Dynamics of Polypeptides by Nonlinear Electronic Spectroscopy of Aromatic Residues: A First-Principles Simulation Study

International audienceThe ability of nonlinear electronic spectroscopy to track folding/unfolding processes of proteins in solution by monitoring aromatic interactions is investigated by first-principles simulations of two-dimensional (2D) electronic spectra of a model peptide. A dominant reaction pathway approach is employed to determine the unfolding pathway of a tetrapeptide, which connects the initial folded configuration with stacked aromatic side chains and the final unfolded state with distant noninteracting aromatic residues. The π-stacking and excitonic coupling effects are included through ab initio simulations based on multiconfigurational methods within a hybrid quantum mechanics/molecular mechanics scheme. It is shown that linear absorption spectroscopy in the ultraviolet (UV) region is unable to resolve the unstacking dynamics characterized by the three-step process: T-shaped[RIGHTWARDS ARROW]twisted offset stacking[RIGHTWARDS ARROW]unstacking. Conversely, pump–probe spectroscopy can be used to resolve aromatic interactions by probing in the visible region, the excited-state absorptions (ESAs) that involve charge-transfer states. 2D UV spectroscopy offers the highest sensitivity to the unfolding process, by providing the disentanglement of ESA signals belonging to different aromatic chromophores and high correlation between the conformational dynamics and the quartic splitting
Fungal-host diversity among mycoheterotrophic plants increases proportionally to their fungal-host overlap

The vast majority of plants obtain an important proportion of vital resources from soil through mycorrhizal fungi. Generally, this happens in exchange of photosynthetically fixed carbon, but occasionally the interaction is mycoheterotrophic, and plants obtain carbon from mycorrhizal fungi. This process results in an antagonistic interaction between mycoheterotrophic plants and their fungal hosts. Importantly, the fungal‐host diversity available for plants is restricted as mycoheterotrophic interactions often involve narrow lineages of fungal hosts. Unfortunately, little is known whether fungal‐host diversity may be additionally modulated by plant–plant interactions through shared hosts. Yet, this may have important implications for plant competition and coexistence. Here, we use DNA sequencing data to investigate the interaction patterns between mycoheterotrophic plants and arbuscular mycorrhizal fungi. We find no phylogenetic signal on the number of fungal hosts nor on the fungal hosts shared among mycoheterotrophic plants. However, we observe a potential trend toward increased phylogenetic diversity of fungal hosts among mycoheterotrophic plants with increasing overlap in their fungal hosts. While these patterns remain for groups of plants regardless of location, we do find higher levels of overlap and diversity among plants from the same location. These findings suggest that species coexistence cannot be fully understood without attention to the two sides of ecological interactions. Keywords:
mycoheterotrophic interactions; mycorrhizal cheaters; niche overlap; niche width; plant coexistence; plant–belowground interaction
Mechanisms of DNA damage, repair, and mutagenesis

Living organisms are continuously exposed to a myriad of DNA damaging agents that can impact health and modulate disease-states. However, robust DNA repair and damage-bypass mechanisms faithfully protect the DNA by either removing or tolerating the damage to ensure an overall survival. Deviations in this fine-tuning are known to destabilize cellular metabolic homeostasis, as exemplified in diverse cancers where disruption or deregulation of DNA repair pathways results in genome instability. Because routinely used biological, physical and chemical agents impact human health, testing their genotoxicity and regulating their use have become important. In this introductory review, we will delineate mechanisms of DNA damage and the counteracting repair/tolerance pathways to provide insights into the molecular basis of genotoxicity in cells that lays the foundation for subsequent articles in this issue. Environ. Mol. Mutagen. 58:235–263, 2017 © 2017 Wiley Periodicals, Inc.National Institute of Environmental Health Sciences (Grant ES-015818
Diet quality determines interspecific parasite interactions in host populations

The widespread occurrence of multiple infections and the often vast range of nutritional resources for their hosts allow that interspecific parasite interactions in natural host populations might be determined by host diet quality. Nevertheless, the role of diet quality with respect to multispecies parasite interactions on host population level is not clear. We here tested the effect of host population diet quality on the parasite community in an experimental study using Daphnia populations. We studied the effect of diet quality on Daphnia population demography and the interactions in multispecies parasite infections of this freshwater crustacean host. The results of our experiment show that the fitness of a low-virulent microsporidian parasite decreased in low, but not in high-host-diet quality conditions. Interestingly, infections with the microsporidium protected Daphnia populations against a more virulent bacterial parasite. The observed interspecific parasite interactions are discussed with respect to the role of diet quality-dependent changes in host fecundity. This study reflects that exploitation competition in multispecies parasite infections is environmentally dependent, more in particular it shows that diet quality affects interspecific parasite competition within a single host and that this can be mediated by host population-level effects