The Erosion of Affirmative Action and its Consequences for the Black-White Educational Attainment Gap

This is the published version

Gauge Field Preheating at the End of Inflation

Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter. We present the results of high-resolution three-dimensional simulations of this model and show this mechanism efficiently preheats the Universe to a radiation-dominated final state.Comment: 8 pages, 8 figure

First limit from a surface run of a 10 liter Dark Matter Time Projection Chamber

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2009.Includes bibliographical references (leaves 35-37).A 10 liter prototype Dark Matter Time Projection Chamber (DMTPC) is operated on the surface of the earth at 75 Torr using carbon-tetrafluoride (CF4) as a target material to obtain a 24.57 gram-day exposure. A limit is set on a likely dark matter candidate, the weakly interacting massive particle. This is the first limit from the DMTPC detector, and the goal is to understand the sensitivity of the detector. In addition, this detector is used to measure the mean energy and attenuation coefficient of electrons propagating in CF4.by Thomas S. Caldwell, Jr.S.B

Review Essay: The Future of National Security Export Controls

In calling for more narrowly focused controls, this study echoes the Bucy Report of 1976, one that called for restrictions on revolutionary rather than evolutionary technology.56 Yet more than a decade after that report was issued, United States export control lists are still weighted toward restricting all exports containing useful technology whether or not the export of an item would advance the capabilities of American adversaries to any degree.17 Unless industry leaders seize the opportunity to reduce the scope of national security export controls as Congress prepares to reauthorize the Export Administration Act, this report, like the Bucy Report before it, may be ignored. The result would be a failure to achieve reforms, consistent with national security interests, that are necessary to allow American exporters to compete fairly in world markets

The Export Administration Amendments Act of 1985

This Note analyzes the EAAA and the administrative regulations it subsequently engendered; it also evaluates their success as of February 1987 in easing the burden of export controls and improving security over United States technological assets. In addition, it considers several complex issues at the heart of export control that Congress fails to address in the EAAA and the consequences of legislative silence in the national security area. Finally, it proposes changes in export control administration and policy that Congress should consider before the EAA comes up for reauthorization in September 1989. Section II examines the development of United States export regulation since World War II and the growing awareness during the past decade of the significance of exports for the United States economy. Section III explains the framework of United States export regulations established by the EAA of 1979. Section IV discusses how the EAAA eliminates controls on low technology items sold to allied nations, speeds administration of export licenses, and upgrades the effectiveness of the Coordinating Committee on Export Controls (COCOM) which coordinates multilateral export controls. Section IV also examines congressional efforts to limit the President\u27s use of export controls for foreign policy purposes. Section V concerns Congressional efforts to strengthen enforcement of United States export controls by enhancing COCOM, defining new crimes, imposing tougher sanctions and increasing enforcement authority. Section VI addresses four volatile issues that Congress either deliberately ignored or only partially addressed in its efforts to pass the EAAA: the extraterritorial impact of United States export controls, the sanctity of existing contracts when Congress imposes embargoes, the role of the Department of Defense in export policy, and the imposition of sanctions against South Africa. In leaving these issues unresolved, Congress ceded effective control of United States exports to the executive branch and undermined the structures that ostensibly regulate United States commerce abroad. Finally, this Note recommends four modifications to the export administration structure in order to reduce impediments to United States exporters not remedied by the EAAA

The Effects of University Affirmative Action Policies on the Human Capital Development of Minority Children: Do Expectations Matter?

Research shows that minority children enter the labor market with lower levels of acquired skill than their white counterparts. The causes of this skill gap, however, are not entirely understood. This paper analyzes one possible cause: the impact of a perceived lack of future opportunities on the human capital investment decisions of minority children and parents. Using NLSY79 data, I take advantage of changes in affirmative action laws regarding university admissions as a natural experiment. I test for changes in a variety of child and parental human capital investment variables such as time spent studying and parental involvement for children below the age of 15. The results show that time spent studying among 7th and 8th grade blacks in the affected states is significantly lower. The results for parental input variables show a fairly consistent negative trend among black parents of younger children. Additionally, cognitive achievement tests are examined and show significant results among the same age groups.affirmative action, skill gaps, human capital investment

Peptide nanoconjugates for tissue diagnostics and molecular imaging

The rise of targeted therapy in cancer treatment has created a strong need for characterization of a patient's tumor before receiving treatment. Many effective cancer drugs are now being targeted to specific proteins present in the tumor, thus only patients who have tumors that express these proteins in appreciable amounts will respond to these kinds of therapy. The most popular method of diagnosing patients is through the practice of immunohistochemistry (IHC), where biopsied patient tissue is subjected to testing for specific protein expression. IHC works by incubating a primary antibody towards the target protein, followed by detection with a secondary antibody containing a reactive enzyme - most commonly, horseradish peroxidase (HRP). IHC procedures are expensive, comprises several steps, involves varying amounts of amplification due to enzyme reactivity, and is only as specific as the primary antibody. Patients receiving treatment using popular drugs targeted at common proteins such as EGFR, c-MET, and PD-L1 have shown varying degrees of responses based on initial IHC diagnosis, even when using FDA-approved diagnostic kits. Due to the discrepancies seen between diagnosis and drug efficacy, we have developed new methods utilizing gold nanoparticles that utilize peptides to target protein biomarkers in human tissues. Peptides which are targeted towards receptors contain only the amino acid sequences which are sufficient for protein binding. Due to their tailored specificity, low cost, scalable production, and ease of modification, peptides can be an attractive method of investigating protein content in human tissues. We investigated the use of peptides combined with imaging agents as diagnostic methods to compare with standard immunohistochemistry procedures. Gold nanorods (GNR) scatter light efficiently in the dark field, and their high surface-area-to-volume ratio allows each nanorod to be coated with many targeting peptides, enhancing specificity of each nanoparticle for the receptor of interest. We first investigated attachment of peptides to GNR that can be used to diagnose common biomarkers EGFR and cMET in tumor tissues. EGFR is one of the most commonly overexpressed proteins in human cancers, and many EGFR-targeted drugs have shown improvement of progression-free survival in patients. During the course of EGFR-targeted treatment it is common that a patient will eventually develop resistance to the EGFR-targeted drugs. One such mechanism is the circumventing of EGFR pathway through upregulation of the c-MET protein on the tumor surface. Once EGFR is internalized and c-MET is the dominant pathway, patients will stop responding to EGFR-targeted drug and the tumor will continue proliferation. There are numerous c-MET drugs on the market for second or third line therapy when resistance occurs with this mechanism, however diagnosis of the c-MET biomarker has become controversial due to poor diagnostic results using the current standard IHC methods. We thus followed up our EGFR diagnostic study by investigating the c-MET protein using the same GNR platform with a cMET-targeted peptide. The GNR-based histochemistry platform shows specificity for the targeted receptors in tumor cell lines and patient tissues, and is able to detect a range of protein expression, rather than relying on binary pathology grades of 1+,2+, or 3+ expression. EGFR and c-MET are two popular biomarkers targeted by pharmaceuticals, and have seen recent success when combined with immune checkpoint inhibitors. The current surge in immuno-oncology has shown excellent response of patients to drugs that inhibit common immune checkpoints such as the interaction between immune receptor Programmed Death 1 (PD-1), expressed on immune cells, and its ligand, PD-L1, expressed on tumor cells. The binding of PD-1 on T cells to PD-L1 on tumor cells will stop the T cells from destroying the tumor. Inhibition of immune checkpoints restore lost host immune function by allowing T-cells to recognize tumor cells as foreign. As with EGFR and c-MET, there has been much debate over whether current methods of diagnosing PD-L1 levels in patients are sufficient due to patient responses varying with respect to the diagnostic recommendation. We extended our peptidebased diagnostic method to investigate PD-L1 by analyzing the crystal structures of PD-L1 and PD-1 and synthesizing a peptide that is specific for the binding region of PD-L1. Using this sequence, we combined our PD-L1 peptide with a biotin molecule, to allow for conventional IHC, and a Cy5 fluorophore to conduct fluorescent investigations of PD-L1 levels in patient tumor tissues. When compared head-to-head with the current FDA-approved PD-L1 diagnostic standard, the peptide-based method shows high specificity for tumors in patient tissues that the FDA-approved diagnostic kits fail to recognize. Due to these results, we believe that peptide-based histochemistry can be used as a specific, cheap alternative to conventional antibody-based IHC

Developing And Implementing Faculty Performance Evaluation: A Collaborative Model

The quality of education is a core property of what makes a university operate, sustain, and grow. To evaluate and measure this core property encompasses a wide range of critical aspects, but one of the control mechanisms will always involve the faculty, the deliverers of education to the primary customer, the student, but also collaboratively to other faculty, other educators, staff, and the community itself.  Faculty, like students constantly change, the challenge being how to inculcate a viable system of performance evaluation that provides a consistently high quality education in the ever changing and information oriented world we live in.  This paper illustrates the process, and problems we’ve experienced and solutions we have used in implementing a new faculty performance evaluation system at our university.  We describe the development of the system; its components, the intended outcomes, issues and resistance encountered as the system was implemented and now, how we envision the growth of the system, and what it needs to remain viable and in tune with our overall strategic plan