Thermo-Mechanical Characterization of Silicon Carbide-Silicon Carbide Composites at Elevated Temperatures Using a Unique Combustion Facility

This research investigated four different types of CMCs in a simulated gas turbine engine hot section condition that involved the simultaneous application of a combustion environment and mechanical fatigue loading using a unique burner rig facility developed for this study at AFIT. Three of the materials were woven Melt-Infiltrated (MI) BN/SiC reinforced by Hi-Nicalon Type S (Hi-Nic-S), Sylramic (Syl) and Sylramic with insitu BN coating (Syl-iBN) fibers, respectively. They were made by the slurry cast method. The other CMC was MI Hi-Nic-S/BN/SiC made using the prepreg MI processing. Prepreg MI CMC and Sylramic-iBN fiber reinforced CMC showed better resistance to the fatigue loading in the combustion environment. Thermally induced stress was determined using finite element analysis to be significant in elevating the stress level locally, causing reduction in the overall stress at which sufficient cracking occurs and leads to failure by means of oxidative degradation. Machined edge was susceptible to cracking and subsequently to oxidation that occurred behind the crack tip

Delays in diagnosis and bladder cancer mortality

BACKGROUND: Mortality from invasive bladder cancer is common, even with high-quality care. Thus, the best opportunities to improve outcomes may precede the diagnosis. Although screening currently is not recommended, better medical care of patients who are at risk (ie, those with hematuria) has the potential to improve outcomes. METHODS: The authors used the Surveillance, Epidemiology, and End Results-Medicare linked database for the years 1992 through 2002 to identify 29,740 patients who had hematuria in the year before a bladder cancer diagnosis and grouped them according to the interval between their first claim for hematuria and their bladder cancer diagnosis. Cox proportional hazards models were fitted to assess relations between these intervals and bladder cancer mortality, adjusting first for patient demographics and then for disease severity. Adjusted logistic models were used to estimate the patient's probability of receiving a major intervention. RESULTS: Patients (n = 2084) who had a delay of 9 months were more likely to die from bladder cancer compared with patients who were diagnosed within 3 months (adjusted hazard ratio [HR], 1.34; 95% confidence interval [CI], 1.20-1.50). This risk was not markedly attenuated after adjusting for disease stage and tumor grade (adjusted HR, 1.29; 95% CI, 1.14-1.45). In fact, the effect was strongest among patients who had low-grade tumors (adjusted HR, 2.11; 95% CI, 1.69-2.64) and low-stage disease (ie, a tumor [T] classification of Ta or tumor in situ; adjusted HR, 2.02; 95% CI, 1.54-2.64). CONCLUSIONS: A delay in the diagnosis of bladder cancer increased the risk of death from disease independent of tumor grade and or disease stage. Understanding the mechanisms that underlie these delays may improve outcomes among patients with bladder cancer. Cancer 2010. © 2010 American Cancer Society.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78303/1/25310_ftp.pd

Measuring The Evolutionary Rate Of Cooling Of ZZ Ceti

We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 +/- 1.4) x 10(-15) s s(-1) employing the O - C method and (5.45 +/- 0.79) x 10(-15) s s(-1) using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 +/- 1.0) x 10(-15) s s(-1). After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 +/- 1.1) x 10(-15) s s(-1). This value is consistent within uncertainties with the measurement of (4.19 +/- 0.73) x 10(-15) s s(-1) for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.NSF AST-1008734, AST-0909107Norman Hackerman Advanced Research Program 003658-0252-2009Astronom

Measuring The Evolutionary Rate Of Cooling Of ZZ Ceti

We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 +/- 1.4) x 10(-15) s s(-1) employing the O - C method and (5.45 +/- 0.79) x 10(-15) s s(-1) using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 +/- 1.0) x 10(-15) s s(-1). After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 +/- 1.1) x 10(-15) s s(-1). This value is consistent within uncertainties with the measurement of (4.19 +/- 0.73) x 10(-15) s s(-1) for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.NSF AST-1008734, AST-0909107Norman Hackerman Advanced Research Program 003658-0252-2009Astronom

Immune and Cell Cycle Checkpoint Inhibitors for Cancer Immunotherapy

The rational design of immunotherapeutic agents has advanced with a fundamental understanding that both innate and adaptive immunity play important roles in cancer surveillance and tumor destruction; given that oncogenesis occurs and cancer progresses through the growth of tumor cells with low immunogenicity in an increasingly immunosuppressive tumor microenvironment. Checkpoint inhibitors in the form of monoclonal antibodies that block cancer’s ability to deactivate and evade the immune system have been widely indicated for a variety of tumor types. Through targeting the biological mechanisms and pathways that cancer cells use to interact with and suppress the immune system, immunotherapeutic agents have achieved success in inhibiting tumor growth while eliciting lesser toxicities, compared to treatments with standard chemotherapy. Development of “precise” bio-active tumor-targeted gene vectors, biotechnologies, and reagents has also advanced. This chapter presents ongoing clinical research involving immune checkpoint inhibitors, while addressing the clinical potential for tumor-targeted gene blockade in combination with tumor-targeted cytokine delivery, in patients with advanced metastatic disease, providing strategic clinical approaches to precision cancer immunotherapy

Optimizing veteran-centered prostate cancer survivorship care: study protocol for a randomized controlled trial

Abstract Background Although prostate cancer is the most common cancer among veterans receiving care in the Veterans Health Administration (VA), more needs to be done to understand and improve survivorship care for this large population. This study, funded by VA Health Services Research & Development (HSR&D), seeks to address the need to improve patient-centered survivorship care for veterans with prostate cancer. Methods/Design This is a two-armed randomized controlled trial (RCT) with a target enrollment of up to 325 prostate cancer survivors per study arm (total anticipated n = 600). Patients will be recruited from four VA sites. Patient eligibility criteria include age range of 40–80 years, one to ten years post-treatment, and currently experiencing prostate cancer symptom burden. We will compare the “Building Your New Normal” program, a personally-tailored automated telephone symptom management intervention for improving symptom self-management to usual care enhanced with a non-tailored newsletter about symptom management. Primary outcomes include changes in symptom burden, bother, and health services utilization at five and 12 months after enrollment. Secondary outcomes include long-term psychosocial outcomes (e.g. subjective health, perceived cancer control). We will use multivariable regression analysis to evaluate the impact of the intervention on primary and secondary outcomes. We will conduct a process evaluation to understand the effective intervention components and explore possibilities for broader implementation and dissemination. Discussion Our central hypothesis is that intervention group participants will have improved and more confident symptom self-management and prostate cancer quality of life following the intervention and that these outcomes will translate to more efficient use of health services. The study results will provide much needed information about how to optimize the quality of care, and life, of veteran prostate cancer survivors. Trial registration ClinicalTrials.gov ID NCT01900561 ; Registered on 22 July 2013.https://deepblue.lib.umich.edu/bitstream/2027.42/136600/1/13063_2017_Article_1925.pd

Nuclear Shell Model Calculations of Neutralino-Nucleus Cross Sections for Silicon 29 and Germanium 73

We present the results of detailed nuclear shell model calculations of the spin-dependent elastic cross section for neutralinos scattering from \si29 and \ge73. The calculations were performed in large model spaces which adequately describe the configuration mixing in these two nuclei. As tests of the computed nuclear wave functions, we have calculated several nuclear observables and compared them with the measured values and found good agreement. In the limit of zero momentum transfer, we find scattering matrix elements in agreement with previous estimates for \si29 but significantly different than previous work for \ge73. A modest quenching, in accord with shell model studies of other heavy nuclei, has been included to bring agreement between the measured and calculated values of the magnetic moment for \ge73. Even with this quenching, the calculated scattering rate is roughly a factor of 2 higher than the best previous estimates; without quenching, the rate is a factor of 4 higher. This implies a higher sensitivity for germanium dark matter detectors. We also investigate the role of finite momentum transfer upon the scattering response for both nuclei and find that this can significantly change the expected rates. We close with a brief discussion of the effects of some of the non-nuclear uncertainties upon the matrix elements.Comment: 31 pages, figures avaiable on request, UCRL-JC-11408

Single-Limb Irradiation Induces Local and Systemic Bone Loss in a Murine Model

Increased fracture risk is commonly reported in cancer patients receiving radiotherapy, particularly at sites within the field of treatment. The direct and systemic effects of ionizing radiation on bone at a therapeutic dose are not well-characterized in clinically relevant animal models. Using 20-week-old male C57Bl/6 mice, effects of irradiation (right hindlimb; 2 Gy) on bone volume and microarchitecture were evaluated prospectively by microcomputed tomography and histomorphometry and compared to contralateral-shielded bone (left hindlimb) and non-irradiated control bone. One week postirradiation, trabecular bone volume declined in irradiated tibias (-22%; p < 0.0001) and femurs (-14%; p = 0.0586) and microarchitectural parameters were compromised. Trabecular bone volume declined in contralateral tibias (-17%; p = 0.003), and no loss was detected at the femur. Osteoclast number, apoptotic osteocyte number, and marrow adiposity were increased in irradiated bone relative to contralateral and non-irradiated bone, whereas osteoblast number was unchanged. Despite no change in osteoblast number 1 week postirradiation, dynamic bone formation indices revealed a reduction in mineralized bone surface and a concomitant increase in unmineralized osteoid surface area in irradiated bone relative to contralateral and non-irradiated control bone. Further, dose-dependent and time-dependent calvarial culture and in vitro assays confirmed that calvarial osteoblasts and osteoblast-like MC3T3 cells were relatively radioresistant, whereas calvarial osteocyte and osteocyte-like MLO-Y4 cell apoptosis was induced as early as 48 hours postirradiation (4 Gy). In osteoclastogenesis assays, radiation exposure (8 Gy) stimulated murine macrophage RAW264.7 cell differentiation, and coculture of irradiated RAW264.7 cells with MLO-Y4 or murine bone marrow cells enhanced this effect. These studies highlight the multifaceted nature of radiation-induced bone loss by demonstrating direct and systemic effects on bone and its many cell types using clinically relevant doses; they have important implications for bone health in patients treated with radiation therapy

UBVRI Light Curves of 44 Type Ia Supernovae

We present UBVRI photometry of 44 type-Ia supernovae (SN Ia) observed from 1997 to 2001 as part of a continuing monitoring campaign at the Fred Lawrence Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics. The data set comprises 2190 observations and is the largest homogeneously observed and reduced sample of SN Ia to date, nearly doubling the number of well-observed, nearby SN Ia with published multicolor CCD light curves. The large sample of U-band photometry is a unique addition, with important connections to SN Ia observed at high redshift. The decline rate of SN Ia U-band light curves correlates well with the decline rate in other bands, as does the U-B color at maximum light. However, the U-band peak magnitudes show an increased dispersion relative to other bands even after accounting for extinction and decline rate, amounting to an additional ~40% intrinsic scatter compared to B-band.Comment: 84 authors, 71 pages, 51 tables, 10 figures. Accepted for publication in the Astronomical Journal. Version with high-res figures and electronic data at http://astron.berkeley.edu/~saurabh/cfa2snIa