18 research outputs found
The Effect of SEBS/Halloysite Masterbatch Obtained in Different Extrusion Conditions on the Properties of Hybrid Polypropylene/Glass Fiber Composites for Auto Parts
Masterbatches from a linear poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) and halloysite nanotubes (HNT-QM) were obtained in different conditions of temperature and shear using two co-rotating twin-screw extruders. The influence of screw configuration and melt processing conditions on the morpho-structural, thermal and mechanical properties of masterbatches at macro and nanoscale was studied. A good dispersion of halloysite nanotubes and better thermal stability and tensile and nanomechanical properties were obtained at a lower temperature profile and higher screw speed. The effect of masterbatches, the best and worst alternatives, on the properties of a polypropylene (PP)–glass fiber (GF) composite was also evaluated. Double hardness, tensile strength and modulus and four times higher impact strength were obtained for PP/GF composites containing masterbatches compared to pristine PP. However, the masterbatch with the best properties led further to enhanced mechanical properties of the PP/GF composite. A clear difference between the effects of the two masterbatches was obtained by nanoindentation and nanoscratch tests. These analyses proved to be useful for the design of polymer composites for automotive parts, such as bumpers or door panels. This study demonstrated that setting-up the correct processing conditions is very important to obtain the desired properties for automotive applications
Transforming growth factor β-mediated micromechanics modulates disease progression in primary myelofibrosis.
To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadPrimary myelofibrosis (PMF) is a Ph-negative myeloproliferative neoplasm (MPN), characterized by advanced bone marrow fibrosis and extramedullary haematopoiesis. The bone marrow fibrosis results from excessive proliferation of fibroblasts that are influenced by several cytokines in the microenvironment, of which transforming growth factor-β (TGF-β) is the most important. Micromechanics related to the niche has not yet been elucidated. In this study, we hypothesized that mechanical stress modulates TGF-β signalling leading to further activation and subsequent proliferation and invasion of bone marrow fibroblasts, thus showing the important role of micromechanics in the development and progression of PMF, both in the bone marrow and in extramedullary sites. Using three PMF-derived fibroblast cell lines and transforming growth factor-β receptor (TGFBR) 1 and 2 knock-down PMF-derived fibroblasts, we showed that mechanical stress does stimulate the collagen synthesis by the fibroblasts in patients with myelofibrosis, through the TGFBR1, which however seems to be activated through alternative pathways, other than TGFBR2.
Keywords: TGF-β; fibroblast activation; invasion; micromechanics; myelofibrosis; proliferation.School of Doctoral Studies-Iuliu Hatieganu University
Romanian Government
Ion Chiricuta Oncology Institute Cluj Napoca
international collaborative grant of the European Economic Space between Romania and Iceland 2020-2022
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A new green, ascorbic acid-assisted method for versatile synthesis of Au-graphene hybrids as efficient surface-enhanced Raman scattering platforms
Dimensions of the destination’s sensory profile. Case study: Muntenia
The development of a destination sensory brand represents a complex
process, given the multitude of product components, and, by integrating their
specific sensory dimensions in their brand platform, can transform the interaction
tourist – destination into a memorable experience. In this sense, the achievement of
the destination’s sensory profile constitutes the first step, in which its perceived
sensory dimensions for the elements of attraction and for the representative types
of tourism are analyzed. In this paper, it is attempted, based on some research, to
outline the sensory profile for the destination Muntenia, starting from the sensory
dimensions perceived by tourists
Sensory marketing strategies. Case study: Oltenia
From the perspective of the tourist, sensory marketing strategies may
result in an experience improvement which leads, in time, to acquiring a positive
destination image, and, from the perspective of the destination, to furthering its
harmonious development. Even though it appears that sensory marketing strategies
can be considered as alternatives for marketing strategies, they actually are
complementary, and their objective (increasing product quality by “turning to the
beginning”, where perception and consumer knowledge start), aims to handle the
senses of the consumer by starting from the identification of his/her needs
Sensory experience – between the tourist and the marketer
In order to influence the decision making process in tourism, and to keep
account with the “tough” competition environment in the current economy,
destinations find themselves “fighting” more and more for the attainment of an
image as favourable as possible in the mind of the tourist. It is for this reason that
the marketer projects the image identity and develops contact points, so that,
through the application of suitable stimuli, the tourist will have a memorable
sensory experience through the stages of pre-consumption, actual consumption and
post-consumption of the travel product. The purpose of the present article is to
evaluate the sensory experience of the tourist – a possible instrument for reducing
the gap between projection and perception, as well as for imagining the travel
product
X-ray photoelectron diffraction study of relaxation and rumpling of ferroelectric domains in BaTi(001)
International audienceThe surface of a ferroelectric BaTi(001) single crystal was studied using synchrotron radiation induced x-ray photoelectron diffraction (XPD), x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and low-energy electron diffraction (LEED). AFM, XPS, and LEED show that the surface is BaO terminated with a (1×1) reconstruction. The Ba 4d, Ti 2p, and O 1s XPD results were compared with multiple scattering simulations for out-of-() and in-plane () polarizations using a genetic algorithm to determine atomic rumpling and interlayer relaxation. Linear combinations of the XPD simulations of the surface structure of each polarization state allow determination of the domain ordering. The best agreement with experiment is found for 55% , 38% , and 7% . The rumpling is smaller at the surface than in the bulk, suggesting that both domain ordering and surface structural changes contribute to screening of the polarization
The Effect of Graphene Nanoplatelets on the Properties of Hybrid Polyamide/Glass Fiber Composites
Currently, the method of solving the issues related to the environment has become a topic of great interest and is approached by researching several directions, such as recycling or the replacement of polluting materials [...
Room Temperature Ferromagnetic Mn:Ge(001)
We report the synthesis of a room temperature ferromagnetic Mn-Ge system obtained by simple deposition of manganese on Ge(001), heated at relatively high temperature (starting with 250 °C). The samples were characterized by low energy electron diffraction (LEED), scanning tunneling microscopy (STM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), superconducting quantum interference device (SQUID), and magneto-optical Kerr effect (MOKE). Samples deposited at relatively elevated temperature (350 °C) exhibited the formation of ~5–8 nm diameter Mn5Ge3 and Mn11Ge8 agglomerates by HRTEM, while XPS identified at least two Mn-containing phases: the agglomerates, together with a Ge-rich MnGe~2.5 phase, or manganese diluted into the Ge(001) crystal. LEED revealed the persistence of long range order after a relatively high amount of Mn (100 nm) deposited on the single crystal substrate. STM probed the existence of dimer rows on the surface, slightly elongated as compared with Ge–Ge dimers on Ge(001). The films exhibited a clear ferromagnetism at room temperature, opening the possibility of forming a magnetic phase behind a nearly ideally terminated Ge surface, which could find applications in integration of magnetic functionalities on semiconductor bases. SQUID probed the co-existence of a superparamagnetic phase, with one phase which may be attributed to a diluted magnetic semiconductor. The hypothesis that the room temperature ferromagnetic phase might be the one with manganese diluted into the Ge crystal is formulated and discussed