303 research outputs found
Maximal gauged supergravity in three dimensions
We construct maximally supersymmetric gauged N=16 supergravity in three
dimensions, thereby obtaining an entirely new class of AdS supergravities.
These models are not derivable from any known higher-dimensional theory,
indicating the existence of a new type of supergravity beyond D=11. They are
expected to be of special importance also for the conjectured AdS/CFT
correspondence. One of their noteworthy features is a nonabelian generalization
of the duality between scalar and vector fields in three dimensions. Among the
possible gauge groups, SO(8)xSO(8) is distinguished as the maximal compact
gauge group, but there are also more exotic possibilities such as F_4 x G_2.Comment: 10 pages, LaTeX2e, minor changes in text, references added, version
to appear in Phys. Rev. Let
Towards industrial strength philosophy: how analytical ontology can help medical informatics
Diagrammar and metamorphosis of coset symmetries in dimensionally reduced type IIB supergravity
Studying the reduction of type IIB supergravity from ten to three space-time
dimensions we describe the metamorphosis of Dynkin diagram for gravity line
"caterpillar" into a type IIB supergravity "dragonfly" that is triggered by
inclusion of scalars and antisymmetric tensor fields. The final diagram
corresponds to type IIB string theory E8 global symmetry group which is the
subgroup of the conjectured E11 hidden symmetry group. Application of the
results for getting the type IIA/IIB T-duality rules and for searching for type
IIB vacua solutions is considered.Comment: 9 pp, 7 figs, LATEX; to be published in JETP Let
Implications of Debunking the "Critical Positivity Ratio" for Humanistic Psychology:Introduction to Special Issue
An extraordinary claim was made by one of the leading researchers within positive psychology, namely, there is a universal-invariant ratio between positive to negative emotions that serves as a unique tipping point between flourishing and languishing in individuals, marriages, organizations, and other human systems across all cultures and times. Known as the "critical positivity ratio," this finding was supposedly derived from the famous Lorenz equation in physics by using the mathematics of nonlinear dynamic systems, and was defined precisely as "2.9013." This exact number was widely touted as a great discovery by many leaders of positive psychology, had tremendous impact in various applied areas of psychology, and, more broadly, and was extensively cited in both the scientific literature and in the global popular media. However, this finding has been demonstrated to be bogus. Since its advent as a relatively new subdiscipline, positive psychology has claimed superiority to its precursor, the subdiscipline of humanistic psychology, in terms of supposedly both using more rigorous science and avoiding popularizing nonsense. The debunking of the critical positivity ratio demonstrates that positive psychology did not live up to these claims, and this has important implications, which are discussed in terms of "romantic scientism" and "voodoo science." In addition, articles in the special issue on the "Implications of Debunking the 'Critical Positivity Ratio' for Humanistic Psychology" are introduced, as they also delve into these concerns
Racial discrepancies in the association between paternal vs. maternal educational level and risk of low birthweight in Washington State
BACKGROUND: The role of paternal factors in determining the risk of adverse pregnancy outcomes has received less attention than maternal factors. Similarly, the interaction between the effects of race and socioeconomic status (SES) on pregnancy outcomes is not well known. Our objective was to assess the relative importance of paternal vs. maternal education in relation to risk of low birth weight (LBW) across different racial groups. METHODS: We conducted a retrospective population-based cohort study using Washington state birth certificate data from 1992 to 1996 (n = 264,789). We assessed the associations between maternal or paternal education and LBW, adjusting for demographic variables, health services factors, and maternal behavioral and obstetrical factors. RESULTS: Paternal educational level was independently associated with LBW after adjustment for race, maternal education, demographic characteristics, health services factors; and other maternal factors. We found an interaction between the race and maternal education on risk of LBW. In whites, maternal education was independently associated with LBW. However, in the remainder of the sample, maternal education had a minimal effect on LBW. CONCLUSIONS: The degree of association between maternal education and LBW delivery was different in whites than in members of other racial groups. Paternal education was associated with LBW in both whites and non-whites. Further studies are needed to understand why maternal education may impact pregnancy outcomes differently depending on race and why paternal education may play a more important role than maternal education in some racial categories
Ethics and Nanopharmacy: Value Sensitive Design of New Drugs
Although applications are being developed and have reached the market, nanopharmacy to date is generally still conceived as an emerging technology. Its concept is ill-defined. Nanopharmacy can also be construed as a converging technology, which combines features of multiple technologies, ranging from nanotechnology to medicine and ICT. It is still debated whether its features give rise to new ethical issues or that issues associated with nanopharma are merely an extension of existing issues in the underlying fields. We argue here that, regardless of the alleged newness of the ethical issues involved, developments occasioned by technological advances affect the roles played by stakeholders in the field of nanopharmacy to such an extent that this calls for a different approach to responsible innovation in this field. Specific features associated with nanopharmacy itself and features introduced to the associated converging technologies- bring about a shift in the roles of stakeholders that call for a different approach to responsibility. We suggest that Value Sensitive Design is a suitable framework to involve stakeholders in addressing moral issues responsibly at an early stage of development of new nanopharmaceuticals
17-allyamino-17-demethoxygeldanamycin treatment results in a magnetic resonance spectroscopy-detectable elevation in choline-containing metabolites associated with increased expression of choline transporter SLC44A1 and phospholipase A2
Abstract Introduction 17-allyamino-17-demethoxygeldanamycin (17-AAG), a small molecule inhibitor of Hsp90, is currently in clinical trials in breast cancer. However, 17-AAG treatment often results in inhibition of tumor growth rather than shrinkage, making detection of response a challenge. Magnetic resonance spectroscopy (MRS) and spectroscopic imaging (MRSI) are noninvasive imaging methods than can be used to monitor metabolic biomarkers of drug-target modulation. This study set out to examine the MRS-detectable metabolic consequences of Hsp90 inhibition in a breast cancer model. Methods MCF-7 breast cancer cells were investigated, and MRS studies were performed both on live cells and on cell extracts. 31P and 1H MRS were used to determine total cellular metabolite concentrations and 13C MRS was used to probe the metabolism of [1,2-13C]-choline. To explain the MRS metabolic findings, microarray and RT-PCR were used to analyze gene expression, and in vitro activity assays were performed to determine changes in enzymatic activity following 17-AAG treatment. Results Treatment of MCF-7 cells with 17-AAG for 48 hours caused a significant increase in intracellular levels of choline (to 266 ± 18% of control, P = 0.05) and phosphocholine (PC; to 181 ± 10% of control, P = 0.001) associated with an increase in expression of choline transporter SLC44A1 and an elevation in the de novo synthesis of PC. We also detected an increase in intracellular levels of glycerophosphocholine (GPC; to 176 ± 38% of control, P = 0.03) associated with an increase in PLA2 expression and activity. Conclusions This study determined that in the MCF-7 breast cancer model inhibition of Hsp90 by 17-AAG results in a significant MRS-detectable increase in choline, PC and GPC, which is likely due to an increase in choline transport into the cell and phospholipase activation. 1H MRSI can be used in the clinical setting to detect levels of total choline-containing metabolite (t-Cho, composed of intracellular choline, PC and GPC). As Hsp90 inhibitors enter routine clinical use, t-Cho could thus provide an easily detectable, noninvasive metabolic biomarker of Hsp90 inhibition in breast cancer patients
- …