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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.
421

Investigations of the interactions of benzylpenicilloic acid with human erythrocytes ; and, RCHDCHDX compounds as stereochemical probes : MINDO/3 and MNDO investigations of conformational preferences in RCHb2sCHb2sX compounds / Investigations of the interactions of benzylpenicilloic acid with human erythrocytes. / RCHDCHDX compounds as stereochemical probes.

Wihebrink, W. Scott 03 June 2011 (has links)
Benzylpenicillin was found to migrate irreversibly into human erythrocytes. No detectable amounts of penicillin bind to the erythrocyte membrane. After migration into the cell, benzylpenicillin is hydrolyzed into benzylpenicilloic acid, which can not migrate out of the cell. DNDS did not affect the appearance of benzylpenicilloic acid in the erythrocyte, therefore showing that: 1) benzylpenicillin does not hydrolyze to benzylpenicilloic acid in the incubation mixture then migrate to the cell, 2) benzylpenicillin migrates into the erythrocyte and is hydrolyzed to benzylpenicilloic acid. Benzylpenicilloic acid does not migrate into erythrocytes.Ball State UniversityMuncie, IN 47306
422

A study of the revegetative capabilities of selected grasses grown on sanitary landfills

Morgan, William Lee 03 June 2011 (has links)
Much emphasis has been placed on the design, operation, and construction of sanitary landfills while the proper reclamation and revegetatiun of completed. sites has often been overlooked.. Revegetation of exposed. landfill surfaces drastically reduces soil erosion, minimizes water infiltration into refuse, helps to control leachate production, and improves site appearance, thus promoting greater public acceptance of sanitary landfills.This research was designed to determine which of selected grasses used. for erosion control were best adapted to the sanitary landfill environment. The experiment was conducted on three sanitary landfills in central Indiana.Results showed that the availability of sufficient plant nutrients was critical for establishing vegetative growth. Significant variations in the performance of the individual grass species was observed.Ball State UniversityMuncie, IN 47306
423

Design and implementation of an extensible language for microcomputers

Minnick, Michael T. 03 June 2011 (has links)
This thesis concerned the design and implementation of an extensible computer language for microcomputer users. The language was shown to provide a minimal set of features which can be extended toward particular applications. The interactive nature of the language was discussed, along with a description of each language feature.Also presented were implementation specifics involving the use of a technique called threaded code. Motivations for the use of extensible languages were discussed, along with suggestions for further extensions and applications.Ball State UniversityMuncie, IN 57406
424

Determining the soil erodibility factor for the Morley, Blount and Pewamo soils in Delaware County, Indiana

Ndukwe, Ernest Amarachukwu 03 June 2011 (has links)
This research determined the soil erodibility factor for Morley, Blount, and Pewamo soils in Delaware County, Indiana, using simulated rainfall mathods. Five test runs were made on each site and the runoff (water and sediment) from each site was collected. Three sites were used for the research and data were collected from five test plots on each site. The T-test was used to determine if significant differences occur between the erodibiltiy factors of the same soil series. One-way analysis of variance was used to determine if significant. differences occur between Morley, Blount, and Pewamo soils in relation to their erodibility factors.The results indicate there are no significant differences between the erodibiltiy factors of the same soil series for Blount and Pewamo soils to the .05 level of confidence. A significant difference was found within the two Morley soils, but the difference could have been due to experimental error and natural soil variation. While there is no significant difference between erodibility values for the Morley and Blount soils, there is significant difference between the Pewamo soil series and the Morley and Blount soil series.This study demonstrates that the use of the rainulator may be a valid method for deriving erodibility factors, especially on higher slopes. The rainulator, however, may not be appropriate for determining erodibility factors on flat or shallow slopes such as found with the Pewamo soil. More erodibility data need to be collected from the same soil series to determine their soil erodibility factors and to verify the effectiveness of using the rainulator for data collection on flat and shallow soils.Ball State UniversityMuncie, IN 47306
425

A study of frog adenosine deaminases : purification and some properties / Frog adenosine deaminases.

Cook, Kenneth Steven 03 June 2011 (has links)
Adenosine deaminase has been shown to consist of three molecular weight forms, A, B, and C. In higher mammals, the A and C forms are dominant while in lower mammals, the B and C forms are dominant. In this work, the B and C forms were isolated from the frog liver and several kinetic parameters were determined.Ammonium sulfate salt fractionation, starting at 40 percent and increased by 5 percent increments to 80 percent was used to separate the two forms. The B form adenosine deaminase was predominantly found in the 50 to 60 percent precipitate fractions while the C form was predominant in precipitate fractions containing more than 60 percent ammonium sulfate. The rechromatographed B and C forms were subjected to isoelectric focusing and thin layer electrophoresis. The B form separated into three activity bands while the C form separated into two activity bands`. Michaelis constant values were determined to be 4.61 X 10-5M and 2.00 X 10-5M for the B and C forms with adenosine as a substrate, respectively. The relative substrate specificity ratio showed that the B form was very specific for adenosine.In conclusion, the B form adenosine deaminase was found to be dominant in the frog liver. The Michaelis constant, relative substrate specificity ratio, thin layer electrophoresis and isoelectric focusing distinguished between the adenosine deaminase B and C forms. The technique of ammonium sulfate fractionation gave excellent separation between the B and C forms of adenosine deaminase.Ball State UniversityMuncie, IN 47306
426

Hooking mortality of bluegill, Lepomis macrochirus, caught on artificial flies, worms, and spinning lures

Cave, Jon B. 03 June 2011 (has links)
This study was designed to investigate the effect that three types of terminal gear and anatomical hooking location have on the mortality rate of bluegill. Worm-baited hooks, artificial flies, single-hook spinning lures, and seines were used to catch bluegill.All groups of fish were placed in aerated holding tanks and observed for 10 days. Results from this research indicate that fish angled with worms had a significantly greater (P<0.001) mortality rate than control group bluegill. However, there was no significant difference between mortalities of the control group and the mortalities of bluegill caught with flies and lures. Worm-hooked bluegill experienced significantly higher mortalities than fish angled with lures (P<0.01) and flies (P<0.05). There was no significant difference in mortalities between fly-hooked and lure-hooked fish.An examination of mortality rates based upon anatomical hooking location reveals that bluegill hooked in the esophagus, gill, tongue, and eye had a mortality rate of 100 percent.Jaw-hooked and lip-hooked bluegill had mortalities of 37.5 percent and 13 percent respectively. Fish hooked in the lip displayed a significantly lower rate of mortality than fish hooked in the esophagus (P<0.001), gill (P-0.001), tongue (P-0.001), and eye (P<0.01). In comparisons among bluegill hooked in the esophagus, gill, tongue, eye, and jaw, no significant level of probability existed.There was a significant difference (P<0.001) between the type of terminal gear and the anatomical hooking location. Worm-baited hooks were generally ingested deeper into the mouth than either artificial flies or beetle spin lures.It can be concluded from this study that worm-baited hooks are the least desirable terminal gear in catch and release programs.Ball State UniversityMuncie, IN 47306
427

A mechanistic study of the photoextrusion of SOb2s to form gbs-lactam rings / Photoextrusion of SOb-sb2b-ss to form b-sgbb-ss-lactam rings.

Gargoum, Ali M. 03 June 2011 (has links)
Irradiation of 1,1-dioxo-2-phenyl-4-thiazolidinone resulted in loss of S02 and formation of a carbon-carbon bond. When (2S,5R) cis-3,5-dimethyl-l,l-dioxo-2-phenyl-4thiazolidinone was photolyzed (through a Vycor filter in t-BuOH/CH3CN) (3S,4S) cis-l,3-dimethyl-4-phenyl-2-azetidinone (i.e., optically active cis a-lactam) was obtained as a major product. The synthesis of (2S,5R) cis-3,5-dimethyl1,1-dioxo-2-phenyl-4-thiazolidinone is described. The verification of optical activity was accomplished by the use of Eu(tfc)3.In addition to the earlier data, the above results have helped us to elucidate the mechanistic pathway of S02 photoextrusion to form p-lactam rings. Sensitization experiments by M. R. Johnson and his use of triplet state quencher have shown that the photoextrusion is a singletstate reaction. Johnson's trapping experiments indicated the existence of a radical intermediate. In the work of this thesis, the observation of optical activity of the cis S-lactam product ruled out a planar diradical and a butadiene-like intermediate. Thus, it can be concluded that the S02 photoextrusion process occurs via discrete radical and diradical intermediates. The diradical is probably formed by stepwise loss of S02 and is so shortlived that optical activity along with cis stereochemistry is maintained.Ball State UniversityMuncie, IN 47306
428

Estimation procedures using order statistics

Diebolt, Daniel T. 03 June 2011 (has links)
In recent times, the role of statistical methods based on order statistics has become more and more significant in statistical inference. Let Y1 < Y2 < • • • < Yn be the order statistics corresponding to a random sample of a size n from a continuous distribution having probability density function f(x; e), e c S2. The purpose of this thesis is mainly to examine the procedures for estimating the parameter e using order statistics.The usual procedures for estimation of unknown parameters are based on the whole sample without taking into account the order in which the sample is taken or without arranging the observations in order of magnitude. Order statistics and estimations based on order statistics are becoming more popular due to their frequent use in nonparametric inferences and in robust procedures. Procedures based on order statistics are particularly useful when the examined data contain one or more extreme values or outliers.This thesis will provide useful insight to the problem of estimation using order statistics. Some works in this field will be studied, reviewed and updated. Estimation based on order statistics using full and censored samples for small and large data sets will be investigated with reference to continuous distributions, such as the normal distribution. In particular, estimation problems as well as hypothesis testing for location and scale parameters of some continuous distributions and estimation of quantiles based on order statistics will be examined.Ball State UniversityMuncie, IN 47306
429

Asymptotic structure of solution of a certain third order differential equation in the neighborhood of a irregular singular point

Almea Silvera, Alfonso R. 03 June 2011 (has links)
In order to introduce the investigation of the present thesis,let us consider the linear homogeneous differential equation:Z2 d3y/dz3 + Z (bo + Bi Zm + b2z2m) d2y/dz2 + (Co + CiZm + C2Z) dy/dZ+ (diZm-1 + d2Z2m-1) Y = 0Here, m is a positive integer, the variable Z is complex and the constants bi, Ci (i=0,1,2) and di (i=1,2) are complex with b2 ≠ 0. It is also assumed that the roots of the indicial equation are such that the difference of no two of them is congruent to zero modulo m.Ball State UniversityMuncie, IN 47306
430

Asymptotic behavior of the solution of a certain third order differential equation near an irregular singular point

Gohari, Nezam 03 June 2011 (has links)
In this master thesis, it is proposed to study the asymptotic behaviour of the solutions of the third order differential equation d3y d2y dyZ2 ____ + z (a0 + a1z) ____ + (b0+b1z+b2z2) ___ + (c0+c1z+c2z2)y = 0 dz3 dz2 dzHere, the variable z and the constants ai (i=0,1), bi, ci (i=0,1,2) are complex with b2 # 0. It is also assumed that no two roots of the indicial equation about the regular singular point z = 0 differ by an integer.Ball State UniversityMuncie, IN 47306

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