951 research outputs found
Transfer function determination of the primary loop of a conceptual nuclear Brayton space powerplant
Transfer functions for primary loop of conceptual nuclear Brayton space power plan
Analisa Pengaruh Gaya Kepemimpinan Transformasional terhadap Kinerja Karyawan dengan Kepuasan Kerja sebagai Variabel Perantara di PT. Anugerah Baru Denpasar
Penelitian ini bertujuan untuk mendeskripsikan serta meneliti pengaruh gaya kepemimpinan transformasional terhadap kinerja karyawan dengan kepuasan kerja sebagai variabel perantara di PT. Anugerah Baru Denpasar. Metode Partial Least Square (PLS) digunakan dalam penelitian ini. Hasil penelitian menunjukkan bahwa gaya kepemimpinan transformasional berpengaruh positif dan signifikan terhadap kepuasan kerja, kepuasan kerja berpengaruh positif tetapi tidak signifikan terhadap kinerja karyawan, dan gaya kepemimpinan transformasional berpengaruh positif dan signifikan terhadap kinerja karyawan
Extracellular Matrix Proteins and Tumor Angiogenesis
Tumor development is a complex process that relies on interaction and communication
between a number of cellular compartments. Much of the mass of a solid tumor is comprised of
the stroma which is richly invested with extracellular matrix. Within this matrix are a host of
matricellular proteins that regulate the expression and function of a myriad of proteins that
regulate tumorigenic processes. One of the processes that is vital to tumor growth and
progression is angiogenesis, or the formation of new blood vessels from preexisting vasculature.
Within the extracellular matrix are structural proteins, a host of proteases, and resident pro- and
antiangiogenic factors that control tumor angiogenesis in a tightly regulated fashion. This paper discusses the role that the extracellular matrix and ECM proteins play in the regulation of tumor angiogenesis
In Situ Characterization of Biomaterials at Solid-Liquid Interfaces Using Ellipsometry in the UV-Visible-NIR Wavelength Range
ErbB2 enhances mammary tumorigenesis, oncogene-independent recurrence and metastasis in a model of IGF-IR-mediated mammary tumorigenesis
<p>Abstract</p> <p>Background</p> <p>The type I insulin-like growth factor receptor (IGF-IR) and ErbB2 (Her-2) are receptor tyrosine kinases implicated in human breast cancer. Both proteins are currently the subject of targeted therapeutics that are used in the treatment of breast cancer or which are in clinical trials. The focus of this study was to utilize our inducible model of IGF-IR overexpression to explore the interaction of these two potent oncogenes.</p> <p>Results</p> <p>ErbB2 was overexpressed in our RM11A cell line, a murine tumor cell line that overexpresses human IGF-IR in an inducible manner. ErbB2 conferred an accelerated tumor onset and increased tumor incidence after injection of RM11A cells into the mammary glands of syngeneic wild type mice. This was associated with increased proliferation immediately after tumor cell colonization of the mammary gland; however, this effect was lost after tumor establishment. ErbB2 overexpression also impaired the regression of established RM11A tumors following IGF-IR downregulation and enhanced their metastatic potential.</p> <p>Conclusion</p> <p>This study has revealed that even in the presence of vast IGF-IR overexpression, a modest increase in ErbB2 can augment tumor establishment <it>in vivo</it>, mediate resistance to IGF-IR downregulation and facilitate metastasis. This supports the growing evidence suggesting a possible advantage of using IGF-IR and ErbB2-directed therapies concurrently in the treatment of breast cancer.</p
Treatment of Acid Mine Drainage with Coal Fly Ash: Exploring the Solution Chemistry and Product Water Quality
A treatment process for Acid mine drainage (AMD) using coal fly ash (CFA) was developed. AMD was treated with CFA as the alkaline agent at different CFA: AMD ratios and pH, electrical conductivity (EC) evolution monitored over time. In a separate experiment two AMD sources with differing chemistry were treated with the same CFA to evaluate the impact of AMD chemistry on the treatment process and product water quality. Various CFA: AMD ratios were stirred in a beaker for a pre-set time and the process water chemistry determined. pH was observed to increase in a stepwise manner with buffer zones observed at 4-4.5, 4.5-7 and 6-8. AMD with low concentration of Al3+, Fe2+, Fe3+ and Mn2+ didn’t exhibit these buffer zones. Two competing processes were observed to control the evolving pH of process water: dissolution of basic oxides (CaO, MgO) from CFA led to pH increase and hydrolysis of AMD species such as Al3+, Fe2+, Fe3+ and Mn2+ led to pH decrease. These processes initiated mechanisms such as precipitation, adsorption and ion exchange that led to decrease in inorganic contaminants as the treatment progressed. Inorganic contaminants removal was directly related to amount of CFA in reaction media. Precipitation of insoluble hydroxides and Al, Fe-oxyhydroxysulphates contributed to removal of major and minor chemical species. Precipitation of gypsum contributed to removal of sulphate. Na, K and Mg remained largely in solution after initial decrease. Significant leaching of B, Sr, Ba, and Mo from CFA was observed and was directly linked to amount of CFA in the reaction media. This will be a shortcoming of the treatment process since other processes may be required to polish up the product water. The treatment of AMD with CFA was observed to depend on CFA, AMD chemistry, treatment time and might therefore be site specific
Mineralogy and Geochemistry of Sub-Bituminous Coal and Its Combustion Products from Mpumalanga Province, South Africa
Use of antibacterial nanoparticles in Endodontics
Several root canal irrigants and medicaments are available to combat endodontic pathogens. However, evidence
of complete elimination of these pathogens by the use of
these solutions is not recorded in the literature. The possible development of resistant bacterial species is one of
the problems related to the efficacy of the currently available irrigants and medicaments. In addition, the complex
anatomy of the root canal system allows endodontic pathogens to be hidden in areas inaccessible to the action of
the irrigating preparations. This is further enhanced by the
protective layer that is formed by the remnants of pulp
tissue, dentin powder and dead cells which inhibit the antibacterial activity of the root canal irrigants and medicaments. Antimicrobial nanoparticles show promising effect
against resistant pathogens in pharmaceutical science as
a result of their unique physio-chemical properties. Unlike
traditionally used antimicrobial agents, these nanoparticles destroy bacterial cells through multiple mechanisms.
The concept of using nanoparticles in endodontics as a
new treatment modality was developed recently and their
antibacterial efficacy against endodontic pathogens was
evaluated by several researchers in many
in vitro studies.
This article reviews some of the currently available literature on laboratory studies that evaluated the efficacy of
nanoparticles against endodontic pathogens
Sol-gel Synthesis, Photo- and Electrocatalytic Properties of Mesoporous TiO2 Modified with Transition Metal Ions
Abstract Mesoporous nanosized titania films modified with Co2+, Ni2+, Mn3+, and Cu2+ ions have been produced by templated sol-gel method and characterized by optical spectroscopy, X-ray diffraction (XRD), and Brunauer, Emmett, and Teller (BET) surface area measurement. Band gap energy and the position of flat band potentials were estimated by photoelectrochemical measurements. The films doped with transition metals possessed higher photocurrent quantum yield, as well as photo- and electrochemical activity compared to undoped samples. Mn+/TiO2 (M–Co, Ni, Mn, Cu) electrodes with low dopant content demonstrate high efficiency in electrocatalytic reduction of dissolved oxygen. Polarization curves of TiO2, TiO2/Ni2+, TiO2/Co2+/3+, and TiO2/Mn3+ electrodes contain only one current wave (oxygen reduction current). It means that reaction proceeds without the formation of an intermediate product H2O2
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