Using a Differential Emission Measure and Density Measurements in an Active Region Core to Test a Steady Heating Model

The frequency of heating events in the corona is an important constraint on the coronal heating mechanisms. Observations indicate that the intensities and velocities measured in active region cores are effectively steady, suggesting that heating events occur rapidly enough to keep high temperature active region loops close to equilibrium. In this paper, we couple observations of Active Region 10955 made with XRT and EIS on \textit{Hinode} to test a simple steady heating model. First we calculate the differential emission measure of the apex region of the loops in the active region core. We find the DEM to be broad and peaked around 3\,MK. We then determine the densities in the corresponding footpoint regions. Using potential field extrapolations to approximate the loop lengths and the density-sensitive line ratios to infer the magnitude of the heating, we build a steady heating model for the active region core and find that we can match the general properties of the observed DEM for the temperature range of 6.3 $<$ Log T $<$ 6.7. This model, for the first time, accounts for the base pressure, loop length, and distribution of apex temperatures of the core loops. We find that the density-sensitive spectral line intensities and the bulk of the hot emission in the active region core are consistent with steady heating. We also find, however, that the steady heating model cannot address the emission observed at lower temperatures. This emission may be due to foreground or background structures, or may indicate that the heating in the core is more complicated. Different heating scenarios must be tested to determine if they have the same level of agreement.Comment: 16 pages, 9 figures, accepted to Ap

Polypectomy Techniques, Endoscopist Characteristics, and Serious Gastrointestinal Adverse Events

Background: A use of polypectomy techniques by endoscopist specialty (primary care, surgery, and gastroenterology) and experience (volume), and associations with serious gastrointestinal adverse events, were examined. Methods: A retrospective follow-up study with ambulatory surgery and hospital discharge datasets from Florida, 1999-2001, was used. Thirty-day hospitalizations due to colonic perforations and gastrointestinal bleeding were investigated for 323,585 patients. Results: Primary care endoscopists and surgeons used hot biopsy forceps/ablation, while gastroenterologists provided snare polypectomy or complex colonoscopy. Low-volume endoscopists were more likely to use simpler rather than complex procedures. For hot forceps/ablation and snare polypectomy, low- and medium-volume endoscopists reported higher odds of adverse events. For complex colonoscopy, higher odds of adverse events were reported for primary care endoscopists (1.74 [95%CI, 1.18 to 2.56]) relative to gastroenterologists Conclusions: Endoscopists regardless of specialty and experience can safely use cold biopsy forceps. For hot biopsy and snare polypectomy, low volume, but not specialty, contributed to increased odds of adverse events. For complex colonoscopy, primary care specialty, but not low volume, added to the odds of adverse events. Comparable outcomes were reported for surgeons and gastroenterologists. Cross-training and continuing medical education of primary care endoscopists in high-volume endoscopy settings are recommended for complex colonoscopy procedures

Comparison of SEER Treatment Data With Medicare Claims

The population-based Surveillance, Epidemiology, and End Results (SEER) registries collect information on first-course treatment, including surgery, chemotherapy, radiation therapy, and hormone therapy. However, the SEER program does not release data on chemotherapy or hormone therapy due to uncertainties regarding data completeness. Activities are ongoing to investigate the opportunity to supplement SEER treatment data with other data sources

Should Cause of Death From the Death Certificate Be Used to Examine Cancer-Specific Survival? A Study of Patients With Distant Stage Disease

Death certificates are used to classify cause of death for studies of cancer survival and mortality. Using data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results program, we evaluated cause of death (site-specific, cancer cause-specific, or other cause of death) for 229,181 patients with distant stage disease during 1994–2003 who died by 2005. Agreement between coded cause of death and initial diagnosis was 85% in patients with only one primary and 64% in patients with more than one primary. Our findings support the usefulness of site and cancer cause-specific causes of death reported on the death certificate for distant stage patients with a single cancer

Race and Insurance Differences in the Receipt of Adjuvant Chemotherapy Among Patients With Stage III Colon Cancer

Although the incidence and mortality of colon cancer in the United States has declined over the past two decades, blacks have worse outcomes than whites. Variations in treatment may contribute to mortality differentials

DETERMINANTS OF ADJUVANT OXALIPLATIN RECEIPT AMONG OLDER STAGE II AND III COLORECTAL CANCER PATIENTS

Controversy exists regarding adjuvant oxaliplatin treatment among older stage II and III colorectal cancer (CRC) patients. We sought to identify patient/tumor, physician, hospital, and geographic factors associated with oxaliplatin use among older patients

Recovery trajectories for long-term health-related quality of life following a road traffic crash injury: results from the UQ SuPPORT study

Background Diminished physical and mental health-related quality of life (HRQoL) is a common consequence of road traffic crash (RTC) injury. This study aimed to (a) determine the probable recovery trajectories in physical and mental HRQoL; (b) examine the impact of posttraumatic stress disorder (PTSD) on HRQoL scores within these trajectory groups; and (c) examine the influence of predictor covariates on trajectory group membership. Methods 336 (63% female, M =44.72; SD =14.77) injured RTC survivors completed the SF-36v2 at approximately 6, 12, and 24 months after sustaining a RTC injury. Participants also completed telephone interviews to assess prior history of psychological disorder and current PTSD at each wave. Results Three trajectories were identified for SF-36v2 Physical Component Score (PCS): ”gradual recovery” (27.3%);”low but improving” (54.7%); and”severe and chronic” (17.9%). Four trajectories were defined for SF36v2 Mental Component Score (MCS): “unaffected” (19.1%);”severe but improving” (24.1%);”severe and declining” (17.3%); and”low but improving” (39.5%). A PTSD diagnosis significantly reduced SF36v2 component scores only in trajectories associated with poorer outcome. Age was predictive of trajectory group membership for PCS, whereas injury severity was predictive of trajectory group membership for MCS. Limitations Use of a compensation seeking sample affects generalizability to the general RTC population. Conclusions This study identified a concerning subgroup of individuals who have chronic and/or declining physical and mental HRQoL that can be impacted by a diagnosis of PTSD. The development of interventions with a special focus on associated psychological injury is needed to improve the HRQoL of at-risk individuals following RTC injury

Identifying Specific Chemotherapeutic Agents in Medicare Data: A Validation Study

Large healthcare databases are increasingly used to examine the dissemination and benefits and harms of chemotherapy treatment in routine practice, particularly among patients excluded from trials (e.g., the elderly). Misclassification of chemotherapy could bias estimates of frequency and association, warranting an updated assessment