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Search Results: 1 - 10 of 270548 matches for " N. W.; "
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Nature’s Particulate Matter with and without Charge and Travelling  [PDF]
Bob W. N. J. Ursem
Open Journal of Biophysics (OJBIPHY) , 2016, DOI: 10.4236/ojbiphy.2016.63008
Abstract: Natures and anthropogenic particulates can travel long distances on wind flows, but negative electrical charge due to friction can increase dispersion. Models for calculations of distance travelling of biological particulate matter with and without charge are never been calculated in a theoretical approach. Nor do we realize the fact that we can calculate actual distances if we take the charge on particles in account. Particles that travel through the air encounter friction. Friction can be described in two ways; either in a smooth constant way through the air with its viscous forces, or in a turbulent chaotic eddies and vortices and other flow instabilities. In case of only viscous forces are to be concerned, it can be described as a lower Reynolds number than one, while in all other setting it always must be described by Reynolds numbers larger than or equal to one. This article describes the calculated effects on particles, either in a low Reynolds number and thus as a Navier-Stokes equation or Stokes’ Law or, in case of non-laminar and complex forces in an equal or higher Reynolds number according to the third Law of Newton. In addition some striking examples of particle travelling are given with evidence of natural particulate matter long distance dispersion.
Laboratory Studies on Phosphorus Removal from Nigeria’s Agbaja Iron Ore by Bacillus Subtilis  [PDF]
C. N. Anyakwo, O.W. Obot
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2011, DOI: 10.4236/jmmce.2011.109063
Abstract: The investigation into whether or not Bacillus subtilis can remove phosphorus from the Nigerian Agbaja iron ore was carried out with careful monitoring of the population of the removing agent as well as pH of the system. 1.00mm/0.50mm, 0.50mm/0.25mm, and 0.25mm/0.125mm ore fractions obtained from sieving of the crushed iron ore in Shital Test kits, were used in sub-merged culture of nutrient broth (NB) medium for 10 weeks. B. subtilis which was part of the rich microflora found on the ore surface was cultivated in nutrient-rich media and later inoculated in sterilized 100ml of NB in 250ml conical flask and 1g of each of the equally sterilized ore fractions was added. At weekly intervals, a set of samples was removed, treated through series of chemical reactions to obtain ammonium phosphomolybdate precipitate which was back-titrated with 0.1 N-HCl to determine the amount of phosphorus left in samples and consequently, the amount removed. The laboratory investigations found out that B. subtilis has the capability to remove phosphorus from the Nigerian Agbaja iron ore, recording an impressive average of 65.73% P. Also found out was the systematic reduction in bacterial cells count in colony forming unit per mililitre, the initial load 3.4x105 cfu/ml increased to 4.8x107 cfu/ml from where it declined to 1.3x106 cfu/ml, which justified the pH trend observed during the process of cumulative phosphorus removal. The reduction in microbial activity may be attributed to antimicrobial components of the ore, pyrite, and other heavy metals which may have affected the phosphorus uptake from ore.
Comparative Phosphorus Removal Capabilities of Eurotium Herbarorium and Clostridium Species on Nigeria’S Agbaja Iron Ore  [PDF]
O. W. Obot, C. N. Anyakwo
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2012, DOI: 10.4236/jmmce.2012.118077
Abstract: A study of phosphorus removal capabilities of Eurotium herbaroriumand Clostridium species from Nigeria’s Agbaja iron ore was carried out. Iron ore sample was crushed, sievedto obtain0.50 mm/0.25 mmparticle size distribution and cultured with mineral oil medium to facilitate microbial growth. Fungi and bacteria that concurrently grew weresubcultured in Sabouard dextrose agar and nutrient agar solutions that support fungal and bacterial growth, respectively,andcharacterized using standard procedures.Ore was exposed to these microbes to effect phosphorus removal in standard media and later analyzed at weekly interval using the standard volumetric ammonium phosphomolybdate method. The fermentation broth media were analyzed for iron, copper, cadmium, zinc, nickel, manganese and lead using the atomic absorption spectrophotometer. The microorganisms markedly removed phosphorus from the ore with 61.48% and 69.20%, respectively. For the funguspH remained in the acidic region and basic for the bacterium. Trace elements analyses of the initial and final orecontaining media recorded marked reduction in the concentration of these elements. A plausible explanation that is supported by literature is that the microorganisms accumulated them. This probably accounts for the drastic decrease in fungal biomass and bacterial density with the concomitant decrease in phosphorus removal observed towards the end.
Prolotherapy Injections for Diastasis Recti: A Case Report  [PDF]
Megan N. Strauchman, Mark W. Morningstar
Case Reports in Clinical Medicine (CRCM) , 2016, DOI: 10.4236/crcm.2016.59052
Abstract: This case report detailed the history and treatment of a female postpartum patient with diastasis recti. Treatment for this patient included the use of prolotherapy, an injection-based therapy using dextrose as the active compound. The solution used during the course of therapy was composed of 6 mL of 50% dextrose, 3 mL of 1% lidocaine, and 1 mL of methylcobalamin (1000 mcg/mL). Injections were administered every 2 weeks for a total of 7 prolotherapy sessions. Following the series of prolotherapy injections, there was a marked closure observed in the diastasis, decreasing from 2.7 cm to 0.5 cm. The patient did not report any side effects, and no complications were observed or recorded. This appears to be the first case report documenting an improvement in abdominal diastasis recti following a course of prolotherapy. Within the limitations of the study design, further research is recommended to evaluate prolotherapy for diastasis recti in postpartum patients.
A Neural Excitability Based Coding Strategy for Cochlear Implants  [PDF]
W. K. Lai, N. Dillier, M. Killian
Journal of Biomedical Science and Engineering (JBiSE) , 2018, DOI: 10.4236/jbise.2018.117014
Abstract: A novel cochlear implant coding strategy based on the neural excitability has been developed and implemented using Matlab/Simulink. Unlike present day coding strategies, the Excitability Controlled Coding (ECC) strategy uses a model of the excitability state of the target neural population to determine its stimulus selection, with the aim of more efficient stimulation as well as reduced channel interaction. Central to the ECC algorithm is an excitability state model, which takes into account the supposed refractory behaviour of the stimulated neural populations. The excitability state, used to weight the input signal for selecting the stimuli, is estimated and updated after the presentation of each stimulus, and used iteratively in selecting the next stimulus. Additionally, ECC regulates the frequency of stimulation on a given channel as a function of the corresponding input stimulus intensity. Details of the model, implementation and results of benchtop plus subjective tests are presented and discussed. Compared to the Advanced Combination Encoder (ACE) strategy, ECC produces a better spectral representation of an input signal, and can potentially reduce channel interactions. Pilot test results from 4 CI recipients suggest that ECC may have some advantage over ACE for complex situations such as speech in noise, possibly due to ECC’s ability to present more of the input spectral contents compared to ACE, which is restricted to a fixed number of maxima. The ECC strategy represents a neuro-physiological approach that could potentially improve the perception of more complex sound patterns with cochlear implants.
Properties of Suborbits of the Dihedral Group Dn Acting on Ordered Subsets  [PDF]
Rose W. Gachogu, Ireri N. Kamuti, Moses N. Gichuki
Advances in Pure Mathematics (APM) , 2017, DOI: 10.4236/apm.2017.78024
Abstract: A group action on a set is a process of developing an algebraic structure through a relation defined by the permutations in the group and the elements of the set. The process suppresses most of the group properties, emphasizing the permutation aspect, so that the algebraic structure has a wider application among other algebras. Such structures not only reveal connections between different areas in Mathematics but also make use of results in one area to suggest conjectures and also prove results in a related area. The structure (G, X) is a transitive permutation group G acting on the set X. Investigations on the properties associated with various groups acting on various sets have formed a subject of recent study. A lot of investigations have been done on the action of the symmetric group Sn on various sets, with regard to rank, suborbits and subdegrees. However, the action of the dihedral group has not been thoroughly worked on. This study aims at investigating the properties of suborbits of the dihedral group Dn acting on ordered subsets of ?X={1,2,...,N}. The action of Dn on X[r], the set of all ordered r-element subsets of X, has been shown to be transitive if and only if n = 3. The number of self-paired suborbits of Dn acting on X[r] has been determined, amongst other properties. Some of the results have been used to determine graphical properties of associated suborbital graphs, which also reflect some group theoretic properties. It has also been proved that when G = Dn acts on ordered adjacent vertices of G, the number of self-paired suborbits is n + 1 if n is odd and n + 2 if n is even. The study has also revealed a conjecture that gives a formula for computing the self-paired suborbits of the action of Dn on its ordered adjacent vertices. Pro-perties of suborbits are significant as they form a link between group theory and graph theory.
Ketersediaan Energi Ransum yang Mengandung Wheat Pollard Hasil Olahan Enzim Cairan Rumen yang Diproses Secara Steam Pelleting pada Ayam Broiler
W. W. Wardani,N. Ramli,W. Hermana
Media Peternakan , 2004,
Abstract: Wheat pollard is a common feed ingredient, but its non starch polysaccharide component is still a limiting factor as an anti nutrition. The combination treatment of enzymes from rumen liquor (DE) and steam pelleting (SP), could change non-starch polysaccharide structure to be more digestible for broiler chicken. Twenty seven broiler chicken of 37 days old were divided into 27 experimental unit and randomly offered one of 9 treatments, that were R1 (DE 0 U/kg + 60oC), R2 (DE 0 U/kg + 80oC), R3 (DE 0 U/kg + 100oC), R4 (DE 620 U/kg + 60oC), R5 (DE 620 U/kg + 80oC), R6 (DE 620 U/kg + 100oC), R7 (DE 1.240 U/kg + 60oC), R8 (DE 1.240 U/kg + 80oC) and R9 (DE 1.240 U/kg + 100oC). The chicken have been fasted for 24 hours and fed by force feeding 30 g/head while water was offered ad libitum. Apparent Metabolizable Energy (AME), Nitrogen Corrected Apparent Metabolizable Energy (AMEn), True Metabolizable Energy (TME), Nitrogen Corrected True Metabolizable Energy (TMEn) and Nitrogen Retention were determined. Three chickens were used for collecting nitrogen and endogenous energy. Data were analyzed by analysis of variance according to completely randomized design with factorial 3x3 and Duncan’s Multiple Range Test. Enzymes dosage and steam treatment did not influence metabolizable energy (AME, AMEn, TME and TMEn) and nitrogen retention. Combination of enzymes (R4 and R8) and steam temperature treatment increased AME, AMEn, TME and TMEn but did not increase nitrogen retention. The result indicated that combination of enzymes at dosage of 620 U/kg with steam 60oC treatment increased the metabolizable energy of wheat pollard based diets.
Nonvanishing tensor polarization of sea quarks in polarized deuterons
N. N. Nikolaev,W. Schaefer
Physics , 1996, DOI: 10.1016/S0370-2693(97)00250-5
Abstract: We propose two new sources of a substantial tensor polarization of sea partons in the deuteron: the diffractive nuclear shadowing which depends on the alignment of nucleons in the polarized deuteron and the nuclear excess of pions in the deuteron which is sensitive to the spin state of the deuteron. The corresponding tensor structure function $b_{2}(x,Q^{2})$ rises towards small x and we predict an about one per cent tensor asymmetry $A_{2}(x,Q^{2})=b_{2}(x,Q^{2})/ F_{2d}(x,Q^{2})$ which by almost two orders in magnitude exceeds the effect evaluated earlier in the impulse approximation. The both mechanisms for tensor structure function break the sum rule $\int dx b_{1}(x,Q^{2})=0$ suggested by Close and Kumano. We comment on the impact of tensor polarization on the determination of the vector spin structure function $g_{1d}(x,Q^{2})$ for the deuteron.
Leading-edge bluntness effects on aerodynamic heating and drag of power law body in low-density hypersonic flow
Santos, W. F. N.;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2005, DOI: 10.1590/S1678-58782005000300004
Abstract: a numerical study is reported on power law shaped leading edges situated in a rarefied hypersonic flow. the sensitivity of the heat flux and drag coefficient to shape variations of such leading edges is calculated by using a direct simulation monte carlo method. calculations show that the stagnation point heating on power law leading edges with finite radius of curvature follows the same relation for classical blunt body in continuum flow; it scales inversely with the square root of the curvature radius at the nose. furthermore, for those leading edges with zero or infinity radii of curvature, the heat transfer behavior is in surprising agreement with that for classical blunt body far from the nose of the leading edge.
O método de fio quente: técnica em paralelo e técnica de superfície
Santos, W. N. dos;
Ceramica , 2002, DOI: 10.1590/S0366-69132002000200007
Abstract: thermal conductivity is one of the most important physical properties of a material. however, its experimental evaluation may presents some specific troubles, and high precision in the determination of the factors involved in its calculation is required. specifically for refractory materials, the experimental technique employed worldwide for thermal conductivity calculations is the hot wire technique, in which the thermal conductivity is calculated starting from the temperature transient generated by an ideal, infinitely thin and long heat source embedded in an infinite surrounding material. in this work comparisons are made when two different techniques for the transient temperature detection are employed: in one of them, the temperature is detected and recorded at the surface of the hot wire (hot wire surface technique), while in the other, the measuring point is located at a fixed distance from the hot wire (hot wire parallel technique). experimental results show a great advantage when using the hot wire surface technique for materials with thermal conductivity higher than 10 w/mk. the time interval which is taken into account in calculations is bigger than that one that would be employed in the hot wire parallel technique in the same experimental conditions, proportioning in this case higher accuracy and reliability in the experimental results obtained.
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