An application of active surface heating for augmenting lift and reducing drag of an airfoil

Application of active control to separated flow on the RC(6)-08 airfoil at high angle of attack by localized surface heating is numerically simulated by integrating the compressible 2-D nonlinear Navier-Stokes equation solver. Active control is simulated by local modification of the temperature boundary condition over a narrow strip of the upper surface of the airfoil. Both mean and perturbed profiles are favorably altered when excited with the same natural frequency of the shear layer by moderate surface heating for both laminar and turbulent separation. The shear layer is found to be very sensitive to localized surface heating in the vicinity of the separation point. The excitation field at the surface sufficiently altered both the local as well as the global circulation to cause a significant increase in lift and reduction in drag

The Effects of Federal Spending on Earnings Change in Appalachia

In this paper we investigate the effects of federal spending on earnings change in Appalachian counties during the 1983-88 recovery and 1989-92 recession. Specifically, we explore the effects of federal spending from grants/research, procurement, salary/wages and defense. The analysis controls for key concepts in the human ecology and new urban sociology. The dependent variables are earnings change for each business cycle from a shift-share analysis, which decomposes county earnings change into that from nationally declining industries. The analysis shows that federal spending has no effect on earnings change, when it is considered as an aggregate measure. However, when federal spending is reclassified into the four categories, spending for grants/research has a positive effect on both measures of earnings change in the 1982-88 recovery. Moreover, the effects of grants/research spending are dependent upon the education level of the county population. However, education by grants/research interaction effect is specific to nonmetro counties in Appalachia. Implications for future research are discussed

Interview with Ed Neubauer

https://digitalcommons.providence.edu/psp470_2023/1004/thumbnail.jp

The C-terminal domain of the Bloom syndrome DNA helicase is essential for genomic stability

BACKGROUND: Bloom syndrome is a rare cancer-prone disorder in which the cells of affected persons have a high frequency of somatic mutation and genomic instability. Bloom syndrome cells have a distinctive high frequency of sister chromatid exchange and quadriradial formation. BLM, the protein altered in BS, is a member of the RecQ DNA helicase family, whose members share an average of 40% identity in the helicase domain and have divergent N-terminal and C-terminal flanking regions of variable lengths. The BLM DNA helicase has been shown to localize to the ND10 (nuclear domain 10) or PML (promyelocytic leukemia) nuclear bodies, where it associates with TOPIIIα, and to the nucleolus. RESULTS: This report demonstrates that the N-terminal domain of BLM is responsible for localization of the protein to the nuclear bodies, while the C-terminal domain directs the protein to the nucleolus. Deletions of the N-terminal domain of BLM have little effect on sister chromatid exchange frequency and chromosome stability as compared to helicase and C-terminal mutations which can increase SCE frequency and chromosome abnormalities. CONCLUSION: The helicase activity and the C-terminal domain of BLM are critical for maintaining genomic stability as measured by the sister chromatid exchange assay. The localization of BLM into the nucleolus by the C-terminal domain appears to be more important to genomic stability than localization in the nuclear bodies

HDACs and the senescent phenotype of WI-38 cells

BACKGROUND: Normal cells possess a limited proliferative life span after which they enter a state of irreversible growth arrest. This process, known as replicative senescence, is accompanied by changes in gene expression that give rise to a variety of senescence-associated phenotypes. It has been suggested that these gene expression changes result in part from alterations in the histone acetylation machinery. Here we examine the influence of HDAC inhibitors on the expression of senescent markers in pre- and post-senescent WI-38 cells. RESULTS: Pre- and post-senescent WI-38 cells were treated with the HDAC inhibitors butyrate or trichostatin A (TSA). Following HDAC inhibitor treatment, pre-senescent cells increased p21(WAF1 )and β-galactosidase expression, assumed a flattened senescence-associated morphology, and maintained a lower level of proteasome activity. These alterations also occurred during normal replicative senescence of WI-38 cells, but were not accentuated further by HDAC inhibitors. We also found that HDAC1 levels decline during normal replicative senescence. CONCLUSION: Our findings indicate that HDACs impact numerous phenotypic changes associated with cellular senescence. Reduced HDAC1 expression levels in senescent cells may be an important event in mediating the transition to a senescent phenotype

Legal Accountability in the Service-Based Welfare State: Lessons from Child Welfare Reform

Current trends intensify the longstanding problem of how the rule-of-law should be institutionalized in the welfare state. Welfare programs are being re-designed to increase their capacities to adapt to rapidly changing conditions and to tailor their responses to diverse clienteles. These developments challenge the understanding of legal accountability developed in the Warren Court era. This Article reports on an emerging model of accountable administration that strives to reconcile programmatic flexibility with rule-of-law values. The model has been developed in the reform of state child protective services systems, but it has potentially broad application to public law. It also has novel implications for such basic rule-of-law issues as the choice between rules and standards, the relation of bureaucratic and judicial control, the proper scope of judicial intervention into dysfunctional public agencies, and the justiciability of positive (or social and economic) rights

The Nature and Frequency of the Gas Outbursts in Comet 67P/Churyumov-Gerasimenko observed by the Alice Far-ultraviolet Spectrograph on Rosetta

Alice is a far-ultraviolet imaging spectrograph onboard Rosetta that, amongst multiple objectives, is designed to observe emissions from various atomic and molecular species from within the coma of comet 67P/Churyumov-Gerasimenko. The initial observations, made following orbit insertion in August 2014, showed emissions of atomic hydrogen and oxygen spatially localized close to the nucleus and attributed to photoelectron impact dissociation of H2O vapor. Weaker emissions from atomic carbon were subsequently detected and also attributed to electron impact dissociation, of CO2, the relative H I and C I line intensities reflecting the variation of CO2 to H2O column abundance along the line-of-sight through the coma. Beginning in mid-April 2015, Alice sporadically observed a number of outbursts above the sunward limb characterized by sudden increases in the atomic emissions, particularly the semi-forbidden O I 1356 multiplet, over a period of 10-30 minutes, without a corresponding enhancement in long wavelength solar reflected light characteristic of dust production. A large increase in the brightness ratio O I 1356/O I 1304 suggests O2 as the principal source of the additional gas. These outbursts do not correlate with any of the visible images of outbursts taken with either OSIRIS or the navigation camera. Beginning in June 2015 the nature of the Alice spectrum changed considerably with CO Fourth Positive band emission observed continuously, varying with pointing but otherwise fairly constant in time. However, CO does not appear to be a major driver of any of the observed outbursts.Comment: 6 pages, 4 figures, accepted for publication in the Astrophysical Journal Letter

Cancer prevention by targeting angiogenesis

Healthy individuals can harbour microscopic tumours and dysplastic foci in different organs in an undetectable and asymptomatic state for many years. These lesions do not progress in the absence of angiogenesis or inflammation. Targeting both processes before clinical manifestation can prevent tumour growth and progression. Angioprevention is a chemoprevention approach that interrupts the formation of new blood vessels when tumour cell foci are in an indolent state. Many efficacious chemopreventive drugs function by preventing angiogenesis in the tumour microenvironment. Blocking the vascularization of incipient tumours should maintain a dormancy state such that neoplasia or cancer exist without disease. The current limitations of antiangiogenic cancer therapy may well be related to the use of antiangiogenic agents too late in the disease course. In this Review, we suggest mechanisms and strategies for using antiangiogenesis agents in a safe, preventive clinical angioprevention setting, proposing different levels of clinical angioprevention according to risk, and indicate potential drugs to be employed at these levels. Finally, angioprevention may go well beyond cancer in the prevention of a range of chronic disorders where angiogenesis is crucial, including different forms of inflammatory or autoimmune diseases, ocular disorders, and neurodegeneration

RNASET2 as a tumor antagonizing gene in a melanoma cancer model

The RNASET2 gene, mapped in 6q27, was previously found to exert control of tumorigenesis in an ovarian cancer system. We present here results indicating a similar control in a melanoma cancer model. Thus, this gene is most likely involved in a common general pathway of tumorigenesis. Moreover, its antitumorigenic activity is manifested in vivo but not in vitro, suggesting that this gene belongs to the growing category of tumor antagonizing/malignancy suppressor genes. A possible role of RNASET2 in the activation of a senescence program, whose responsible locus was mapped in the same chromosomal 6q27 region, seems to be inconsistent with our data