Maryland Space Grant Consortium

I have used the Hipparcos Input Catalog, together with Kurucz model stellar atmospheres, and information on the strength of the interstellar extinction, to create a model of the expected intensity and spectral distribution of the local interstellar ultraviolet radiation field, under various assumptions concerning the albedo a of the interstellar grains. (This ultraviolet radiation field is of particular interest because of the fact that ultraviolet radiation is capable of profoundly affecting the chemistry of the interstellar medium.) By comparing my models with the observations, I am able to conclude that the albedo a of the interstellar grains in the far ultraviolet is very low, perhaps a = 0.1. I also advance arguments that my present determination of this albedo is much more reliable than any of the many previous (and conflicting) ultraviolet interstellar grain albedo determinations. Beyond this, I show that the ultraviolet background radiation that is observed at high galactic latitudes must be extragalactic in origin, as it cannot be backscatter of the interstellar radiation field.

In discussing the important question of why physics understanding is so poor, Rustum Roy mentions the Annenberg Project video A Private Universe 1 1. Annenberg Project,A Private Universe, available for viewing online at http://www.learner.org/resources/series28.html. and expresses his conclusion that “less than 10% of the American populace can handle any kind of abstraction” ( Physics Today, Physics Today 0031-9228 60 8 2007 10 https://doi.org/10.1063/1.2774081. August 2003, page 10 ). I also recommend the video, but for the opposite reason. After my first viewing, I felt about it as Roy does, but after additional viewings (including a very recent refresher), I suggest we consider the possibility that the culprit is inadequate teaching, not “incapable” students.Perhaps the sharpest image that first-time viewers of the video come away with is ninth-grade Heather’s insistence that the light from the Sun in winter does not go directly to Earth but instead bounces toward Earth at a sharp angle, somewhere out in space. A private universe indeed!The film should be viewed several times. Initially, Heather had had no instruction at all in astronomy. Before the second round of filming, she received instruction, including diagrams, on summer (light striking Earth at 90°, which, by the way, it never does at her northern latitude) and winter (light striking obliquely). Her teacher told her that in winter, the light is “indirect.” My guess is that the instructor, unfortunately, wanted to avoid using the word “oblique” as being too technical.Almost anyone in our society knows what indirect lighting is. If the room you are in is illuminated by indirect lighting, you don’t see the source of the light at all; what you see is only light that has bounced off something at a sharp angle, and from there has proceeded to your eye (directly or indirectly). Heather is most likely just trying to integrate her correct understanding of indirect lighting with the instructor’s insistence that winter sunlight is indirect.That exercise provides no support at all for the idea that Heather is incapable of handling abstraction. I urge that any such sweeping and consequential conclusion be established in a peer-reviewed education journal before it is otherwise disseminated to the physics community.A fundamental reason why physics education is in such poor shape is typified by Michael Riordan’s Opinion piece in the same issue of Physics Today (page 50). Although I absolutely agree with Riordan’s insistence on experimental testing of theories, his emphasis on the nonexistent (in physics) distinction between things that are “real” and things that are purely “mathematical” is wrong. We know from quantum mechanics that nothing is real, except for the observations themselves.REFERENCESection:ChooseTop of pageREFERENCE <<CITING ARTICLES1. Annenberg Project,A Private Universe, available for viewing online at http://www.learner.org/resources/series28.html. Google Scholar© 2004 American Institute of Physics.

Abstract Myeloid-Derived Suppressor Cells (MDSC) polarize macrophages to a Type II tumor-promoting phenotype via MDSC-macrophage crosstalk. We previously demonstrated that MDSC produce IL-10 which inhibits macrophage production of IL-12, and MDSC production of IL-10 is dependent on TLR4 and enhanced by cell-cell contact with macrophages. However, the role of inflammation in MDSC-macrophage crosstalk is not well defined. To determine the role of inflammation, we utilized wild type, IL-6-/-, and IL-10-/- mice bearing syngeneic 4T1 mammary carcinoma. IL-10 is classically an anti-inflammatory cytokine. In contrast, IL-6 is a pro-inflammatory cytokine that is secreted by activated Type 1 macrophages, is found at higher levels in tumor-bearing patients, and is an inducer of MDSC. 4T1-induced MDSC and macrophages express both IL-6 and IL-10 receptors, suggesting that they have the potential to respond to both cytokines. To determine if IL-6 and IL-10 contribute to tumor progression by modulating MDSC-macrophage crosstalk, MDSC from wild type or IL-10-/- mice bearing 4T1 tumors were cultured with macrophages from wild type or IL-6-/- BALB/c mice. Although MDSC are typically pro-inflammatory cells, they significantly decreased macrophage production of IL-6, suggesting that MDSC can also function as anti-inflammatory cells. IL-6 levels are important in vivo since primary 4T1 tumors grow more slowly in IL-6-deficient mice, and these mice have significantly extended survival compared to wild type BALB/c mice. Anti-inflammatory effects are further exacerbated by macrophages themselves, since their production of IL-6 increases MDSC production of IL-10. However, macrophage-produced IL-6 affects MDSC indirectly, as incubation of MDSC with exogenous IL-6 in the absence of macrophages does not increase IL-10 production. Although IL-10 is classically considered as an anti-inflammatory cytokine, it contributes to tumor progression because 4T1-bearing IL-10-/- mice have delayed primary tumor progression and extended survival vs. wild type mice. These data demonstrate that MDSC have both pro-inflammatory and anti-inflammatory effects and that MDSC-macrophage cross-talk contributes to the overall milieu of IL-10 and IL-6 within the tumor microenvironment. Since IL-6 is a signature cytokine of anti-tumor M1-like macrophages, these data also suggest that although MDSC may decrease inflammation through their production of IL-10, this effect neither promotes the development of tumoricidal macrophages nor decreases tumor progression. Supported by NIH R01 CA115880, RO1CA84232, and DOD BCRP W81XWH-11-1-0115 Citation Format: Daniel W. Beury, Katherine H. Parker, Suzanne Ostrand-Rosenberg. Inflammation of the tumor microenvironment is regulated by myeloid derived suppressor cell and macrophage crosstalk. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2876. doi:10.1158/1538-7445.AM2013-2876

It is not difficult to see why K–12 science education is in trouble. In his letter, Art Hobson (Physics Today, December 2002, page 12) approvingly quotes the authors of Science for All Americans for their view that, “without a scientifically literate population, the outlook for a better world is not promising.” 1 1. F. J. Rutherford, A. Ahlgren, Science for All Americans, Oxford U. Press, New York (1990). Available online at http://www.project2061.org/tools/sfaaol/sfaatoc.htm. However the authors of that document promote obsolete and incorrect information about the foundations of physics. On page 47, for example, they write, “Scientists continue to investigate atoms and have discovered even smaller constituents of which electrons … are made.” That same sentence is repeated in Benchmarks for Science Literacy, 2 2. American Association for the Advancement of Science, Benchmarks for Science Literacy, Oxford U. Press, New York (1993), p. 80. which is currently used as the foundation for curriculum reform across the US.Much more serious than any specific erroneous statement is the document’s almost grotesque failure at the foundation of physics. You probably thought that the basic premise of the modern theory of matter was quantum mechanics, or at least that it was the standard model, right? Well, Science for All Americans says, “The basic premise of the modern theory of matter is that the elements consist of a few different kinds of atoms—particles far too tiny to see in a microscope—that join together in different configurations to form substances. There are one or more—but never many—kinds of these atoms for each of the approximately 100 elements.” The first sentence indicates that the way you form “substances” is by combining different isotopes of a single element!Is it any wonder that our K–12 education system is in such bad shape when such an illiterate, antiquated report has been circulated and used for more than a decade?NASA’s Maryland Space Grant Consortium has been trying for the past decade to bring university-level science professionalism into Maryland’s K–12 school system. It is an uphill task.REFERENCESSection:ChooseTop of pageREFERENCES <<1. F. J. Rutherford, A. Ahlgren, Science for All Americans, Oxford U. Press, New York (1990). Available online at http://www.project2061.org/tools/sfaaol/sfaatoc.htm. Google Scholar2. American Association for the Advancement of Science, Benchmarks for Science Literacy, Oxford U. Press, New York (1993), p. 80. Google Scholar© 2003 American Institute of Physics.