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Ciprofloxacin Cardiotoxicity and Hepatotoxicity in Humans and Animals  [PDF]
Elias Adikwu, Nelson Brambaifa
Pharmacology & Pharmacy (PP) , 2012, DOI: 10.4236/pp.2012.32028
Abstract:

Ciprofloxacin is generally well tolerated; the most common adverse effects include gastro intestinal tract, central nervous system and hematological system effects. Recently rising cases of Ciprofloxacin associated toxicity have been reported. Experiment using animal models and clinical experience showed that Ciprofloxacin induced cardiotoxicity is marked by increase QT and QTC interval and prolonged action potential duration. This increases the risk of arrhythmia (tosarde de pointes). Ciprofloxacin induced cardiotoxic effect could be associated with blocking cardiac voltage—gated potassium channels particularly the rapid component (IKr) of the delayed rectifier potassium current. Drug interaction with inhibitors of Cytochrome P450 (CYP) mediated metabolism could be one of the underlying mechanisms. Several cases of Ciprofloxacin induced hepatoxicity have been also reported. These were characterized by extensive hepatocellular necrosis, mixed inflammatory infiltrate and abundant esinophils in the liver. Elevated liver enzymes which include serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and gramma-glutamyltranferase

Modification of the Newtonian Dynamics in ΛFRW-Cosmology an Alternative Approach to Dark Matter and Dark Energy  [PDF]
Nelson Falcón
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.48A003
Abstract:

Modified Newtonian Dynamics (MoND) is an empirically motivated modification of Newtonian gravity at largest scales, to explain rotation curves of galaxies, as an alternative to nonbaryonic dark matter. But MoND theories can hardly connect to the formalism of relativistic cosmology type Friedmann-Robertson-Walker. Presently work intends the existence of one scalar potential, with non gravitational origin, that would solve these problems. This potential Yukawa type inverse is build starting from a specular reflection of the potential of Yukawa: null in very near solar system, slightly attractiveness in ranges of interstellar distances, very attractiveness in distance ranges comparable to galaxies cluster and repulsive to cosmic scales. The consequences of this potential are discussed, through Cosmological Model Tipe Friedmann-Roberston-Walker with cosmological term in function of the distance (lambda like function of r). In the cosmological model so raised the critical density of matter is consistent with the observed density does not include dark matter, MoND theory is deduced for interstellar scales and consequently would explain rotation curves. Also it is shown that Yukawa type inverse does not alter the predictions of the Cosmic Microwave Background neither the primordial nucleosynthesis in early universe; and can be explain the large-scale structure formation.

A Homeowner-Based Methodology for Economic Analysis of Energy-Efficiency Measures in Residences  [PDF]
Nelson Fumo, Roy Crawford
Open Journal of Energy Efficiency (OJEE) , 2013, DOI: 10.4236/ojee.2013.22013
Abstract:

Residential energy-efficiency measures, besides energy savings, provide opportunities for improvement of thermal comfort, air quality, lighting quality, and operation. However, all these benefits sometimes are not enough to convince a homeowner to pay the incremental cost associated with the energy-efficiency measure. The objective of this work is to develop a methodology for the economic evaluation of residential energy-efficiency measures that can simplify the economic analysis for the homeowner while taking into consideration all factors associated with the purchase, ownership, and selling of the house with the energy-efficiency measure. The methodology accounts for direct and indirect economic parameters associated to an energy-efficiency measure; direct parameters such as the mortgage interest and fuel price escalation rate, and indirect parameters such as savings account interest and marginal income tax rate. The methodology also considers different cases based on the service life of the energy-efficiency measure and loss of efficiency through a derating factor. To estimate the market value, the methodology uses the future energy cost savings instead of the cost of the EEM. Results from the methodology offer to homeowner annual net savings and net assets. The annual net savings gives the homeowner a measure of the annual positive cash flow that can be obtained from an energy-efficiency project; but more important, the net assets offer a measure of the added net wealth. To simplify and increase the use of the methodology by homeowners, the methodology has been implemented in an Excel tool that can be downloaded from the TxAIRE’s website.

Multiple Endemic Solutions in an Epidemic Hepatitis B Model without Vertical Transmission  [PDF]
Nelson Owuor Onyango
Applied Mathematics (AM) , 2014, DOI: 10.4236/am.2014.516242
Abstract:

This paper examines the dynamics of Hepatitis B via a Susceptible Exposed Infectious Recovered (SEIR) type epidemic model. Previous studies have shown that Hepatitis B is characterized by multiple endemic solutions, a matter which may be of concern in developing control strategies. We identify the possible causes of multiple endemic solutions in a Hepatitis B model and conclude that the dependance of the probability of carriage development  (q(Λ)) on the force of infection (Λ) is the main reason for multiple endemicity. Other factors such as a large proportion of infants that are not vaccinated (ω) may also enhance the possibility of multiple endemicity. The role of carriers may also play a key role in the possibility of such complex dynamics, i.e., when infectiousness of carriers-(α) is high, the probability of existence of multiple endemic equilibrium solutions is increased. In our arguments, the traditional reproduction number R0< 1 which we define here by a function G(0) < 1 does not imply stability of disease-free equilibrium.

Uniformly Bounded Set-Valued Composition Operators in the Spaces of Functions of Bounded Variation in the Sense of Riesz  [PDF]
Wadie Aziz, Nelson Merentes
International Journal of Modern Nonlinear Theory and Application (IJMNTA) , 2015, DOI: 10.4236/ijmnta.2015.44017
Abstract: We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function.
Climate Change Science & Propaganda  [PDF]
Michael D. Nelson
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.612105
Abstract: This article addresses the relationship between science and propaganda using the Climate Change controversy as a study model. The United Nations International Panel on Climate Change (IPCC) is the recognized leader on this model issuing multiple Assessment Reports. This review begins with a discussion of the basics—what is propaganda and how does it work, followed by whether the IPCC adopted or rejected it. Next explored is how propaganda can be seamlessly fused into “report writing” in a way that arouses and makes interesting humdrum details. Some unexpected results emerged from current and historical observation data involving the Greenhouse theory, CO2 sources, ocean pH, sea levels, and ice balances. The final section confronts whether “a point of view” constrains objectivity in favor of outcome. The overall conclusion is that the earth is boringly healthy.
Soil-Based Biofiltration for Air Purification:Potentials for Environmental and Space LifeSupport Application  [PDF]
Mark Nelson, Hinrich L. Bohn
Journal of Environmental Protection (JEP) , 2011, DOI: 10.4236/jep.2011.28125
Abstract: Soil biofiltration, also known as soil bed reactor (SBR), technology was originally developed in Germany to take advantage of the diversity in microbial mechanisms to control gases producing malodor in industrial processes. The approach has since gained wider international acceptance and continues to see improvements to maximize microbial and process efficiency and extend the range of problematical gases for which the technology can be an effective control. We review the basic mechanisms which underlay microbial soil processes involved in air purification, advantages and limitations of the technology and the current research status of the approach. Soil biofiltration has lower capital and operating/energetic costs than conventional technologies and is well adapted to handle contaminants in moderate concentrations. The systems can be engineered to optimize efficiency though manipulation of temperature, pH, moisture content, soil organic matter and airflow rates. Soil air biofiltration technology was modified for application in the Biosphere 2 project, which demonstrated in preparatory research with a number of closed system testbeds that soil could also support crop plants while also serving as soil filters with airpumps to push air through the soil. This Biosphere 2 research demonstrated in several closed system testbeds that a number of important trace gases could be kept under control and led to the engineering of the entire agricultural soil of Biosphere 2 to serve as a soil filtration unit for the facility. Soil biofiltration, coupled with food crop production, as a component of bioregenerative space life support systems has the advantages of lower energy use and avoidance of the consumables required for other air purification approaches. Expanding use of soil biofiltration can aid a number of environmental applications, from the mitigation of indoor air pollution, as a method of reducing global warming impact of methane (biogas), improvement of industrial air emissions and prevention of accidental release of toxic gases.
Structural analysis, metamorphism, and geochemistry of the Archean granitoids-greenstones of the Sukumaland Greenstone Belt around Geita Hills, Northern Tanzania  [PDF]
Nelson Boniface, Abdul H. Mruma
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.48070
Abstract: Greenstone rocks, which include Banded Iron Formations (BIFs), tuffs, volcanic flows (basalt, andesite and rhyolite), and clastic sedimentary rocks (shale-mudstone, greywacke-sandstone and conglomerate), crop out around Geita Hills and are flanked by granites and granodiorites. BIFs and tuffs occupy larger area than other lithological units, which crop out as patches. Structural analysis indicates that layers of green-stone rocks are folded and display a regional fold axis with an attitude of 320o/40o. Low-grade metamorphic mineral assemblages (actinolite-epidote-chlorite in basalts and muscovite-epidote-chlorite in granitoids) are common in these rocks; this indicates a regional metamorphism at greenschist facies. However, BIFs and basalts are locally metamorphosed to epidote-amphibolite and amphibolite facies. Basalts belong to the tholeiite series whereas granites, diorites and rhyolites belong to the calcalkaline series. Chondrite normalized rare earth element pattern of basalt is flat and plot slightly below the average N-MORB values suggesting the enrichment of the light rare earth elements, which means that mantle magma source was an E-MORB. Granitoids and rhyolites have strong affinities to the continental arc source magma displaying strong enrichments in the LREEs with (La/Sm)N values ranging between 2.53 and 3.95 in rhyolites and between 4.08 and 5.40 in granitoids. The granitoids are classified as the I-type synorogenic metaluminous granites and granodiorites. Geochemical signatures suggest that the Geita Hills basalts erupted at the enriched mid ocean ridge setting of the back arc setting, and the granites, granodiorite and rhyolite formed in a volcanic arc setting particularly the continental arc.
Synthesis and Characterization of Poly(styrene-co-acrylamide) Polymers Prior to Electrospinning  [PDF]
Adebola A. Oketola, Nelson Torto
Advances in Nanoparticles (ANP) , 2013, DOI: 10.4236/anp.2013.22015
Abstract:

Electrospun nanofibers present a new and rapidly growing research area due to their pronounced micro and nano characteristics associated with high surface area to volume ratio. Poly(styrene-co-acrylamide) and polystyrene polymers were synthesized by boiling temperature soap free emulsion polymerization in aqueous medium with potassium peroxosulphate as the initiator. The resulting polymers were dissolved in dimethylformamide and teterahydrofuran (DMF: THF) (4:1) to form polymer solutions that were electrospun into fiber mats with diameters ranging from 1.84 - 2.53 μm and 5.01 μm, respectively. The fibers were characterized by Fourier transform infrared spectroscopy (FTIR) equipped with universal ATR sampling accessory (4000 - 400 cm-1). The morphology and size were examined by a scanning electron miscroscope (SEM) and the thermal properties by thermogravimetric analysis (TGA). The FTIR spectra of the poly(styrene-co-acrylamide) revealed the presence of acrylamide on the polystyrene chain. Thus, surface modification of polystyrene with acrylamide is possible in a single step polymerization reaction prior to electrospinning.

Theoretical Deduction of the Hubble Law Beginning with a MoND Theory in Context of the ΛFRW-Cosmology  [PDF]
Nelson Falcon, Andrés Aguirre
International Journal of Astronomy and Astrophysics (IJAA) , 2014, DOI: 10.4236/ijaa.2014.44051
Abstract: We deduced the Hubble law and the age of the Universe, through the introduction of the Inverse Yukawa Field (IYF), as a non-local additive complement of the Newtonian gravitation (Modified Newtonian Dynamics). As a result, we connected the dynamics of astronomical objects at great scale with the Friedmann-Robertson-Walker ΛFRW) model. From the corresponding formalism, the Hubble law can be expressed as = (4π[G]/c)r, which was derived by evaluating the IYF force at distances much greater than 50 Mpc, giving a maximum value for the expansion rate of the universe of H0(max≈ 86.31 km·s-1Mpc-1, consistent with the observational data of 392 astronomical objects from NASA/IPAC Extragalactic Database (NED). This additional field (IYF) provides a simple interpretation of dark energy as the action of baryonic matter at large scales. Additionally, we calculated the age of the universe as 11 Gyr, in agreement with recent measurements of the age of the white dwarfs in the solar neighborhood.
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