Massachusetts Institute of Technology

About: Massachusetts Institute of Technology is a education organization based out in Cambridge, Massachusetts, United States. It is known for research contribution in the topics: Population & Laser. The organization has 116795 authors who have published 268000 publications receiving 18272025 citations. The organization is also known as: MIT & M.I.T..

Research Commentary: Desperately Seeking the IT in IT Research--A Call to Theorizing the IT Artifact

Abstract: The field of information systems is premised on the centrality of information technology in everyday socio-economic life. Yet, drawing on a review of the full set of articles published inInformation Systems Research ( ISR) over the past ten years, we argue that the field has not deeply engaged its core subject matter--the information technology (IT) artifact. Instead, we find that IS researchers tend to give central theoretical significance to the context (within which some usually unspecified technology is seen to operate), the discrete processing capabilities of the artifact (as separable from its context or use), or the dependent variable (that which is posited to be affected or changed as technology is developed, implemented, and used). The IT artifact itself tends to disappear from view, be taken for granted, or is presumed to be unproblematic once it is built and installed. After discussing the implications of our findings, we propose a research direction for the IS field that begins to take technology as seriously as its effects, context, and capabilities. In particular, we propose that IS researchers begin to theorize specifically about IT artifacts, and then incorporate these theories explicitly into their studies. We believe that such a research direction is critical if IS research is to make a significant contribution to the understanding of a world increasingly suffused with ubiquitous, interdependent, and emergent information technologies.

Vaccination with Irradiated Tumor Cells Engineered to Secrete Murine Granulocyte-Macrophage Colony-Stimulating Factor Stimulates Potent, Specific, and Long-Lasting Anti-Tumor Immunity

Abstract: To compare the ability of different cytokines and other molecules to enhance the immunogenicity of tumor cells, we generated 10 retroviruses encoding potential immunomodulators and studied the vaccination properties of murine tumor cells transduced by the viruses. Using a B16 melanoma model, in which irradiated tumor cells alone do not stimulate significant anti-tumor immunity, we found that irradiated tumor cells expressing murine granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulated potent, long-lasting, and specific anti-tumor immunity, requiring both CD4+ and CD8+ cells. Irradiated cells expressing interleukins 4 and 6 also stimulated detectable, but weaker, activity. In contrast to the B16 system, we found that in a number of other tumor models, the levels of anti-tumor immunity reported previously in cytokine gene transfer studies involving live, transduced cells could be achieved through the use of irradiated cells alone. Nevertheless, manipulation of the vaccine or challenge doses made it possible to demonstrate the activity of murine GM-CSF in those systems as well. Overall, our results have important implications for the clinical use of genetically modified tumor cells as therapeutic cancer vaccines.

The Skill Content of Recent Technological Change: An Empirical Exploration

Abstract: We apply an understanding of what computers do to study how computerization alters job skill demands. We argue that computer capital (1) substitutes for workers in performing cognitive and manual tasks that can be accomplished by following explicit rules; and (2) complements workers in performing nonroutine problem-solving and complex communications tasks. Provided these tasks are imperfect substitutes, our model implies measurable changes in the composition of job tasks, which we explore using representative data on task input for 1960 to 1998. We find that within industries, occupations and education groups, computerization is associated with reduced labor input of routine manual and routine cognitive tasks and increased labor input of nonroutine cognitive tasks. Translating task shifts into education demand, the model can explain sixty percent of the estimated relative demand shift favoring college labor during 1970 to 1998. Task changes within nominally identical occupations account for almost half of this impact.

A cortical representation of the local visual environment

Abstract: Medial temporal brain regions such as the hippocampal formation and parahippocampal cortex have been generally implicated in navigation and visual memory. However, the specific function of each of these regions is not yet clear. Here we present evidence that a particular area within human parahippocampal cortex is involved in a critical component of navigation: perceiving the local visual environment. This region, which we name the 'parahippocampal place area' (PPA), responds selectively and automatically in functional magnetic resonance imaging (fMRI) to passively viewed scenes, but only weakly to single objects and not at all to faces. The critical factor for this activation appears to be the presence in the stimulus of information about the layout of local space. The response in the PPA to scenes with spatial layout but no discrete objects (empty rooms) is as strong as the response to complex meaningful scenes containing multiple objects (the same rooms furnished) and over twice as strong as the response to arrays of multiple objects without three-dimensional spatial context (the furniture from these rooms on a blank background). This response is reduced if the surfaces in the scene are rearranged so that they no longer define a coherent space. We propose that the PPA represents places by encoding the geometry of the local environment.