Let $(R,\mathfrak m)$ be a commutative Noetherian local ring. There is variety of nice results about approximately Cohen-Macaulay rings. These were done by Goto. In this paper we prove some these for modules and generalize the concept rings to modules. It seen that when $M$ an module, any proper ideal $I$ have $grade(I,M) \geq \dim_R M -\dim_R M/IM -1$. Specially $R$ itself, obtain interval $gr...

Although women earn approximately 50 percent of science, technology, engineering and math (STEM) bachelor’s degrees, more than 70 scientists engineers are men. We explore a potential determinant this STEM gender gap using newly collected data on the career trajectories United States Air Force Academy students. Specifically, we examine effects being assigned female science professors occupation ...

This paper considers the effect of child care costs on two labor market outcomes for single mothers—whether to participate in the labor market and whether to receive welfare. Hourly child care expenditures are estimated for all women in the sample (using data drawn from the 1992 and 1993 panels of the SIPP), whether or not they are currently using nonmaternal child care. These expenditures are ...

Avian infectious bronchitis virus (IBV) causes tremendous economic losses to the poultry industry worldwide. Different serotypes of this virus show little cross-protection. The present study investigated the relationship between differences in the genotype based on the N-terminus of the spike protein and the protection provided by vaccination with IBVs. Cross-immunization tests were performed u...

Erklärung Ich erkläre hiermit, dass ich die vorliegende Arbeit selbstständig verfasst und keine anderen als die angegebenen Quellen und Hilfsmittel verwendet habe.

who had a major influence on my mathematical development and who always had time for me and my questions. I am especially indebted to Prof. Hilgert for his guidance. He encouraged me to spend a semester abroad and proposed the topic of this thesis to me. I am also grateful to the " Studienstiftung des deutschen Volkes " for two brilliant summer academies and the opportunity to meet a lot of gre...

Single-letter visual acuity is impaired by nearby flanking stimuli, a phenomenon known as contour interaction. We showed previously that when foveal acuity is degraded by a reduction of letter contrast, both the magnitude and angular spatial extent of foveal contour interaction remain unchanged. In this study, we asked whether contour interaction also remains unchanged when foveal visual acuity...