Integral Neutron Multiplicity Measurements from Cosmic Ray Interactions in Lead

Sixty element 3He neutron multiplicity detector systems were designed, constructed and tested for use in cosmic ray experiments with a 30-cm cube lead target. A series of measurements were performed for the cosmic ray configuration at ground level (3 meters water equivalent, mwe), in the St. Petersburg metro tunnel (185 mwe), and in the Pyhäsalmi mine in Finland (583 and 1185 mwe). Anomalous coincidence events with charged cosmic ray particles at sea level produced events with 100-120 neutrons due possibly to the total disintegration of the Pb nucleus. These events were also detected at 185 mwe, but the particles causing such disintegration are currently unidentified. We present examples of preliminary data from the various measurements and discuss future plans for underground experiments including possible searches for Weakly Interacting Massive Particles (WIMP, dark matter)

Abstract 17248: Statin Therapy Increases Coronary Artery Calcification Scores

Introduction: Coronary artery calcification (CAC) assessment is a noninvasive test to determine atherosclerotic burden. There has been a discordance with the well-known lipid lowering and cardiovascular protection of statins and the progression of CAC in small trials with narrow inclusion criteria. We performed a subgroup analysis of the Multi-Ethnic Study of Atherosclerosis (MESA) dataset to assess the impact of statins on patients with a baseline CAC score of 0. Hypothesis: Statin usage will cause patients to have a higher CAC scores despite lowering LDL and reducing cardiac mortality. Methods: A subgroup analysis (3235 patients) was performed on the MESA dataset to identify patients with a CAC score of 0 at baseline. Statin usage and cholesterol values were reviewed at 4 examination points. Multivariate regression was performed. Results: The number of patients using statins (Table 1) and lipid levels (Table 2) increased throughout the study as expected for an aging population. A consistently larger increase in CAC score was noted in patients receiving statins; this difference was demonstrated in all stratified groups by Framingham score (Table 3). Table 4 shows the results of multivariate linear regression. Excluding gender, statins had the largest impact on CAC; more than any established cardiovascular risk factor. Conclusion: This large subgroup analysis of the MESA dataset demonstrates that statins are associated with increasing CAC score. While this is in contrast to the well-established cardiovascular protection of statin therapy, it adds to the growing literature that statin use is associated with progression of CAC, even in low risk patients with baseline CAC of 0. One hypothesis for this finding is that statins promote coronary atheroma calcification which ultimately results in plaque stabilization and less likelihood for progression to unstable plaques. It is therefore necessary for clinicians to take into account statins when interpreting CAC scores

Integral Neutron Multiplicity Measurements from Cosmic Rays Interactions in Lead

Sixty element 3He neutron multiplicity detector systems were designed, constructed and tested for use in cosmic ray experiments with a 30‐cm cube lead target. A series of measurements were performed for the cosmic ray configuration at ground level (3 meters water equivalent, mwe), in the St. Petersburg metro tunnel (185 mwe), and in the Pyhasalmi mine in Finland (583 and 1185 mwe). Anomalous coincidence events with charged cosmic ray particles at sea level produced events with 100–120 neutrons due possibly to the total disintegration of the Pb nucleus. These events were also detected at 185 mwe, but the particles causing such disintegration are currently unidentified. We present examples of preliminary data from the various measurements and discuss future plans for underground experiments including possible searches for Weakly Interacting Massive Particles (WIMP, dark matter