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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

The use of an automatic controlled gain amphifier in nuclear lifetime measurements

Parvizi, Behram 03 June 2011 (has links)
In this study a unique pulse amplifier, with automatic controlled gain, was used to measure nuclear lifetimes. The significance of this circuit is that it reduces the spread in pulse amplitudes of those pulses selected by Ge(Li) and NaI(Tl) detectors from a single channel analyzer. In the first part of this study a coincidence circuit composed of an Ortec module with Ge(Li) and NaI(Tl) detectors was utilized. The coincidence curves of two different sources, 22Na (0.511 MeV from positron annihilation) and 133Ba (0.081-MeV excited state), were recorded by a multichannel analyzer. In the second part of this research the unique pulse amplifier was added to the original coincidence circuit. The coincidence curve of the two sources was again recorded, and comparison of the two methods was made. A twenty five percent improvement in time resolution for 22Na and a twenty percent improvement for 133Na was achieved.Ball State UniversityMuncie, IN 47306
152

Methods of educating the nursing mother

Peterson, John C. 03 June 2011 (has links)
AbstractThis study compared breast-feeding success rates for nursing mothers from three different population groups: (1) those with no medically supervised education, (2) those with exposure to supportive medical staff and to a patient education handout on breast-feeding, and (3) those with exposure to the handout and to a videotape on breast-feeding shown in the hospital during the first few days postpartum. Success was defined as using breast milk as the primary means of infant nutrition at five to six weeks postpartum. It was found that educating mothers in an organized fashion significantly improves success rates over that seen when organized patient education was not offered (p<.001). The group educated by postpartum videotapes tended to do better than the group educated by only patient education handouts and interested medical staff. This relationship was not significant at the .05 level (.05<p<.10), but was strong enough to warrant further investigation. Lack of correct information was related to all of the reasons for not breast-feeding and for prematurely stopping breast-feeding.Honors CollegeBall State UniversityMuncie, IN 47306
153

Investigation of bacterial mouth flora of Ball State University students

Langona, Michael R. 03 June 2011 (has links)
The occurrence of pathogenic and non-pathogenic bacteria isolated from the throats of Ball State University students was investigated in a surveillance study utilizing weekly throat swabbings. The reference population was divided into three groups: the control; semi-control; and experimental groups respectively. The experimental group was exposed to numerous bacterial pathogens and non-pathogens biweekly during one academic quarter. The objective of the study was to determine if the throat flora of an individual within the experimental group underwent colonial changes in relation to the bacterial organisms the individual was exposed to. The results of the study indicate that bacterial colonial changes did not occur within the throat region following bacterial exposure.Ball State UniversityMuncie, IN 47306
154

Kinetic studeis of human spleen adenosine deaminases

Creazzola, Maria Assunta 03 June 2011 (has links)
The hydrolysis of adenosine, 2-deoxyadenosine and 6-chloropurine riboside by adenosine deaminase preparations from human spleen has been investigated, and Km and Vm values have been determined. The effect of the substrate on the reaction velocity was followed over a 250-fold range Results showed no deviation from Michaelis-Menten kinetics. The effect of pH on Vm, Vm/Km, and the apparent activation energy was examined. Inactivation of the enzyme by p-chloromercuribenzoate suggests the involvement of one or more SH groups. Competitive inhibition by inosine and the fact that ammonia is not, an inhibitor support a reaction mechanism involving a ternary complex. The apparent activation energy of the a parameter was smaller or less sensitive to temperature than the ß parameter.Ball State UniversityMuncie, IN 47306
155

A characterization of the various types of set functions and an examination of the relationships existing among them

Petty, James Alan 03 June 2011 (has links)
The investigation of this thesis is introduced by finding all the relationships existing among the various types of set functions. Characterizations of the different set functions will be formulated in order to facilitate the construction and identification of each type of set function considered. This problem has important applications to measure theory and integration.Ball State UniversityMuncie, IN 47306
156

Asymptotic behaviour of the solutions of a certain second order differential equation in the vicinity of an irregular singular point

Zvimba, Charles Muchazoziva 03 June 2011 (has links)
In this thesis, it is contemplated to study the asymptotic behaviour of the solutions of the differential equationz2d2y + z(bo +b1zm ) dy +(co + c1zm + c2 z2m)y =0 (1) dz2 dzHere m is a positive integer, the variable z is regarded complex as are the constants bi(i=0,1) and ci(i=0,1,2) with c2 ≠ 0. Then in the language of Fuch's theory the differential equation (1) will have a regular singular point at z=0 and an irregular singular point at z=θ. The indicial equation about z=0 is found to beh(h-1) + boh + co = 0(2)It is also assumed that the difference of the roots of (2) are incongruent to zero modulo m.Ball State UniversityMuncie, IN 47306
157

Stratigraphic study of a glacio-fluvial feature near Mount PLeasant, Indiana by Stephen R. Myers. / Glacio-fluvial feature near Mount Pleasant, Indiana.

Myers, Stephen R. 03 June 2011 (has links)
This study was concerned with the origin and stratigraphic relationship of a ridge-swales complex located in and near Mount Pleasant, Indiana. Borehole data, water well logs, seismic refraction surveys, and electrical resistivity surveys were combined to create three cross-sections which illustrate the stratigraphic relationship of the feature under scrutiny. In addition, textural analyses of outwash, esker, and ridge samples were performed to discriminate between outwash and esker material; the results were compared to the ridge samples.The textural analyses failed to discriminate convincingly between esker and outwash; however, the cross-sections display the ridge-valley complex as a broad sheet of outwash sand and gravel subsequently eroded by glacial meltwater.Ball State UniversityMuncie, IN 47306
158

Age changes of muscle fiber type in rat gastrocnemius

Tropf, Thomas E. 03 June 2011 (has links)
A comparative study on the age changes in rat skeletal muscle tissue was performed using rats of different ages. The gastrocnemius muscle from rats of 3, 6, and 22 months of age was removed and examined for the presence of Type I fibers. Myosin ATPase histochemistry was used to differentiate between Type I and Type II fibers. A count of the number of Type I fibers in the entire gastrocnemius was made using fiber maps obtained from the stained muscle samples. The total number of fibers in some of the muscle samples was also determined.The results indicated a steady decline in the total number of muscle fibers from the ages of 3 to 22 months. With the exception of the 6 month group, the number of Type I fibers remained fairly constant. However, there was a definite increase in the percentage of Type I fibers found in the 22 month rats. An increase in the diameter of the muscle fibers in the 22 month rats was also observed.Ball State UniversityMuncie, IN 47306
159

Critical aspects of swim performance / Swim performance.

Troup, John Patrick 03 June 2011 (has links)
The purpose of this investigation was to determine the relative importance of strength and anaerobic lactate metabolism to swimming performance. Although strength has been shown to play an integral part in swim performance, its development is not clearly understood.In addition, the emphasis to be placed on strength vs. anaerobic lactate utilization was examined in the various acre groups.Ball State UniversityMuncie, IN 47306
160

Ecological factors affecting the distribution of Volvox species in small ponds

White, Arthur J. 03 June 2011 (has links)
Factors influencing the distribution of Volvox spp. in 41 ponds of the Lake Itasca region, Minnesota, were investigated from May 25 through July 14, 1980. Twenty-two ponds had Volvox populations. The three species of Volvox found were: V. aureus Ehr., V. globator L. and V. tertius Meyer. Usually only one species was present in a pond with rare co-occurrence of two species. Only two of the 41 ponds contained two Volvox species simultaneously for a short time.Group comparison tests of ponds with and without Volvox showed three parameters to be significant (P > 0.05 level). Mean total phosphorus was higher in ponds with Volvox (x = 1.75 uM/1) than without (x = 0.95 uM/1). Mean temperature (20.4°C versus 21.8°C) and mean pH calculated from H+ concentrations (6.32 versus 6.76) were both lower in ponds with Volvox than in ponds without. Field observations of one pond revealed a patchy distribution of V. globator related to macrophyte abundance. Laboratory investigations confirmed that V. globator colonies orient to the aquatic moss Drepanocladus revolvens.Ball State UniversityMuncie, IN 47306

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