2,283 research outputs found
Stem cells conditioned medium: a new approach to skin wound healing management
Stem cell biology has gained remarkable interest in recent years, driven by the hope of finding cures for numerous diseases including skin wound healing through transplantation medicine. Initially upon transplantation, these cells home to and differentiate within the injured tissue into specialised cells. Contrariwise, it now appears that only a small percentage of transplanted cells integrate and survive in host tissues. Thus, the foremost mechanism by which stem cells participate in tissue repair seems to be related to their trophic factors. Indeed, stem cells provide the microenvironment with a wide range of growth factors, cytokines and chemokines, which can broadly defined as the stem cells secretome. In in vitro condition, these molecules can be traced from the conditioned medium or spent media harvested from cultured cells. Conditioned medium now serves as a new treatment modality in regenerative medicine and has shown a successful outcome in some diseases. With the emergence of this approach, we described the possibility of using stem cells conditioned medium as a novel and promising alternative to skin wound healing treatment. Numerous pre-clinical data have shown the possibility and efficacy of this treatment. Despite this, significant challenges need to be addressed before translating this technology to the bedside.Article Link:
http://onlinelibrary.wiley.com/doi/10.1002/cbin.10138/pd
Characterization of the domain chaos convection state by the largest Lyapunov exponent
Using numerical integrations of the Boussinesq equations in rotating cylindrical domains with realistic boundary conditions, we have computed the value of the largest Lyapunov exponent lambda1 for a variety of aspect ratios and driving strengths. We study in particular the domain chaos state, which bifurcates supercritically from the conducting fluid state and involves extended propagating fronts as well as point defects. We compare our results with those from Egolf et al., [Nature 404, 733 (2000)], who suggested that the value of lambda1 for the spiral defect chaos state of a convecting fluid was determined primarily by bursts of instability arising from short-lived, spatially localized dislocation nucleation events. We also show that the quantity lambda1 is not intensive for aspect ratios Gamma over the range 20<Gamma<40 and that the scaling exponent of lambda1 near onset is consistent with the value predicted by the amplitude equation formalism
Cross-Border Financing by the Industrial Sector Increases Competition in the Domestic Banking Sector
We predict that access to cross-border financing by the industrial sector reduces firms' reliance on domestic banks, thereby leading to lower rents for banks and greater competition in the domestic banking sector. We also predict that banks take on more risk to offset these lost rents and remain competitive. Using mandatory adoption of International Financial Reporting Standards (IFRS) to identify variation in cross-border financing, we find evidence consistent with our hypotheses. Additional tests verify that the effects emanate from the demand side (i.e., firms not relying on banks) rather than the supply side (i.e., banks not willing to lend to firms). Overall, we document how competition from overseas financial markets influences the domestic banking sector
Origin and evolution of the zodiacal dust cloud
The astrophysical importance of the zodiacal cloud became more apparent. The most useful source of information on the structure of the zodiacal cloud is the Infrared Astronomical Satellite (IRAS) observations. A substantial fraction of the extensive IRAS data set was analyzed. Also, a numerical model was developed (SIMUL) that allows to calculate the distribution of night-sky brightness that would be produced by any particular distribution of dust particle orbits. This model includes the effects of orbital perturbations by both the planets and solar radiation, it reproduces the exact viewing geometry of the IRAS telescope, and allows for the eccentricity of the Earth's orbit. SIMUL now is used to model not just the solar system dust bands discovered by IRAS but the whole zodiacal cloud
Remote sensing applications: an overview
Remote Sensing (RS) refers to the science of identification of earth surface features and estimation of their geo-biophysical properties using electromagnetic radiation as a medium of interaction. Spectral, spatial, temporal and polarization signatures are major characteristics of the sensor/target, which facilitate target discrimination. Earth surface data as seen by the sensors in different wavelengths (reflected, scattered and/or emitted) is radiometrically and geometrically corrected before extraction of spectral information. RS data, with its ability for a synoptic view, repetitive coverage with calibrated sensors to detect changes, observations at different resolutions, provides a better alternative for natural resources management as compared to traditional methods. Indian Earth Observation (EO) programme has been applications-driven and national development has been its prime motivation. From Bhaskara to Cartosat, India's EO capability has increased manifold. Improvements are not only in spatial, spectral, temporal and radiometric resolutions, but also in their coverage and value-added products. Some of the major operational application themes, in which India has extensively used remote sensing data are agriculture, forestry, water resources, land use, urban sprawl, geology, environment, coastal zone, marine resources, snow and glacier, disaster monitoring and mitigation, infrastructure development, etc. The paper reviews RS techniques and applications carried out using both optical and microwave sensors. It also analyses the gap areas and discusses the future perspectives
University small satellite program-ANUSAT
Indian Space Research Organization (ISRO) over the last 3 decades has steadily progressed towards establishment of space system for communication, Earth observation and disaster warning for national development. Also, the launchers for placing both Earth observation and communication satellites have been developed. While these efforts are being sustained on a continuous basis, ISRO initiated Small Satellite Program few years ago for demonstration of new technologies that can be adopted to operational mission as well as Small Satellite Earth Observation program to complement the existing earth observation mission. Also realizing the importance of steady flow of engineers and scientists in Space Technology, ISRO has been pursuing to promote development of micro-satellite at Indian universities that will provide hands-on experience to the university students in Space Technology and also developing new technologies for the future. Anna University at Chennai, India, has taken up the first micro-satellite program within the university environment. The micro-satellite development will be carried out at Aerospace Research Centre in Anna University with review and funding support from ISRO. The project will be implemented through involvement of students, researchers and faculty staff. The satellite is a simple spinning satellite carrying store and forward payload being the first mission and weighs less than 50 kg. The Project has commenced in January 2002. The preliminary design review of the satellite has been completed in December 2002. The micro-satellite is scheduled for launch in 2005 as an auxiliary payload in ISRO's launcher PSLV (Polar Satellite Launch Vehicle)
Misregulation of the Proline Rich Homeodomain (PRH/HHEX) protein in cancer cells and its consequences for tumour growth and invasion
The Proline Rich Homeodomain protein (PRH), also known as Haematopoietically Expressed homeobox (HHEX), is an essential transcription factor in embryonic development and in the adult. The PRH protein forms oligomeric complexes that bind to tandemly repeated PRH recognition sequences within or at a distance from PRH target genes and recruit a variety of PRH-interacting proteins. PRH can also bind to other transcription factors and co-regulate specific target genes either directly through DNA binding, or indirectly through effects on the activity of its partner proteins. In addition, like some other homeodomain proteins, PRH can regulate the translation of specific mRNAs. Altered PRH expression and altered PRH intracellular localisation, are associated with breast cancer, liver cancer and thyroid cancer and some subtypes of leukaemia. This is consistent with the involvement of multiple PRH-interacting proteins, including the oncoprotein c-Myc, translation initiation factor 4E (eIF4E), and the Promyelocytic Leukaemia protein (PML), in the control of cell proliferation and cell survival. Similarly, multiple PRH target genes, including the genes encoding Vascular Endothelial Growth Factor (VEGF), VEGF receptors, Endoglin, and Goosecoid, are known to be important in the control of cell proliferation and cell survival and/or the regulation of cell migration and invasion. In this review, we summarise the evidence that implicates PRH in tumourigenesis and we review the data that suggests PRH levels could be useful in cancer prognosis and in the choice of treatment options
Magnetic field measurements of sharp-lined Ap stars
Previous observations suggested that Ap and Bp stars exhibit a bimodal
distribution of surface magnetic field strengths and that actually only few or
no stars exist with magnetic dipole field strengths below 300 G down to a few
Gauss. As the number of Ap and Bp stars currently known to possess weak
magnetic fields is not large, it is necessary to carry out additional
spectropolarimetric studies of Ap and Bp stars to prove whether the assumption
of the existence of a critical value for the stability of magnetic fields is
realistic. In this study, we present high-resolution HARPSpol magnetic field
measurements for a sample of Ap stars with sharp spectral lines with a view to
characterize the strengths of their magnetic fields. Out of the studied seven
sharp-lined stars, two stars, HD 174779 and HD 203932, exhibit a rather weak
longitudinal magnetic field with \left=-45\pm3 G and
\left=21\pm4 G, respectively. Additionally, TESS
observations were used to test previous conclusions on the differentiation of
rotation periods of Ap and Bp stars. Apart from HD 189832 and HD 203932, all
other studied sharp-lined stars have long rotation periods. Since an
explanation for the slow rotation of Ap stars is currently missing, additional
studies of slowly rotating Ap and Bp stars are necessary to improve our
understanding of the formation and evolution of Ap and Bp stars.Comment: 13 pages, 18 figures, 2 tables. Accepted to be published in MNRA
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