Search for a Dark Matter-Induced Annual Modulation Signal in NaI(Tl) with the COSINE-100 Experiment.

We present new constraints on the dark matter-induced annual modulation signal using 1.7 years of COSINE-100 data with a total exposure of 97.7 kg yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA's claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7 cpd/kg/keV background rate on average in the 2-6 keV energy region of interest. Using a χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067 cpd/kg/keV and 127.2±45.9 d, respectively.

First Direct Search for Inelastic Boosted Dark Matter with COSINE-100.

A search for inelastic boosted dark matter (IBDM) using the COSINE-100 detector with 59.5 days of data is presented. This relativistic dark matter is theorized to interact with the target material through inelastic scattering with electrons, creating a heavier state that subsequently produces standard model particles, such as an electron-positron pair. In this study, we search for this electron-positron pair in coincidence with the initially scattered electron as a signature for an IBDM interaction. No excess over the predicted background event rate is observed. Therefore, we present limits on IBDM interactions under various hypotheses, one of which allows us to explore an area of the dark photon parameter space that has not yet been covered by other experiments. This is the first experimental search for IBDM using a terrestrial detector.

Effects of marathon running on cardiac markers and endothelin-1 in EIH athletes.

The aim of the present study was to determine the changes in cardiac makers and endothelin-1 (ET-1) in marathoners with exercise induced hypertension compared to normotensive controls before and after running a marathon. Among a total of 70 volunteers, 10 marathoners with systolic blood pressure (SBP) greater than 210 mmHg during a treadmill exercise stress test were selected as an exercise-induced hypertension group (EIH) and 10 marathoners with normal SBP were selected as a control group (CON). Blood was collected from all volunteers 2 h before and immediately after a marathon: creatinine kinase (CK), CK-MB, cardiac tropoin-I (cTnI), N-terminal pro-brain natriuretic peptide (NT-proBNP), and endothelin-1(ET-1). Cardiac markers, CK, CK-MB, and CK-MB/CK ratio significantly increased in both EIH and CON; significance was not observed between the groups. Significant increases were not observed in high sensitive-C reactive protein (hs-CRP) after the race nor between the groups. Significant increases in cTnI and NT-proBNP were observed after the race in both groups. In addition, EIH showed greater increase than CON after the race. In conclusion, increased vascular tone in EIH during a marathon increased blood pressure and myocardial burden which in turn increased myocardial cell membrane permeability to further increase myocardial tension to the point of cTnI release.

Cardiac markers of EIH athletes in ultramarathon.

This study aimed to investigate effects of a 100-km ultramarathon on cardiac markers of exercise-induced-hypertensive marathoners. 10 marathoners with exercise-induced hypertension and 10 normal marathoners participated in the study. Their blood samples were collected before starting, at 50 km, and after finishing the course (100 km). Creatinine kinase was more significantly increased in the exercise-induced-hypertensive group than in the normal group at 100 km (P<0.05). N-terminal pro-brain nutriuretic peptide was significantly increased in the exercise-induced-hypertensive group at 50 km and 10 km (P<0.05) which was significant being doubled compared to the normal group (P<0.05). Exercise-induced-hypertensive marathoners showed a significant triple-increase in C-Reactive protein at 100 km (P<0.05). In conclusion, although the exercise-induced-hypertensive runners did not have myocardial damage during the 100 km ultramarathon, they had higher myocardial stress and more damage in active muscles due to a bloodstream disability.