The measurement and analysis of similarity degree on data from two types of seismic recorders

Seismic instruments are widely used in projects related to geophysical prospecting. Quality data from seismic recorders help to determine subterranean structures with high precision. This paper first introduces a field experiment carried out by deploying seismic stations equipped with two kinds of seismic recorders: GEI (China) and Reftek 130 (USA). Then, the three-component seismograms from GEI are measured and evaluated by comparing with those from Reftek 130 in different aspects: waveforms in time and frequency domain, quantitative analysis by calculation and statistic of correlation coefficient, and signal to noise ratio of seismic signal. Our results were presented by multiple images as the following: (I) Both the time and frequency waveforms of GEI were almost exactly coincident with those of Reftek 130, with over 98.60 percent of the correlation coefficients in the time domain within 0.95–1.0, and all those in the frequency domain above 0.9977. (II) The accurate time lag estimation of GEI’s signal was gained by the lag and correlation algorithms based on left–right sliding windows. The GEI clock was 7.3545 ns behind the Reftek 130 clock after every 1 s, which could be utilized to correct the internal clock to improve the synchronous accuracy of seismic recorders. (III) Some seismic signals from GEI were obviously stronger than those from Reftek 130. Our results may potentially promote and support the optimization of seismic recorders and their application in geophysics methods

Associations Between Life's Essential 8 and Insulin Resistance Among Nondiabetic Adults

Background Insulin resistance (IR) is closely linked to cardiometabolic diseases. Preventing and improving IR in nondiabetic populations is critically important. We aimed to investigate the relationship between Life's Essential 8 (LE8), the latest tool from the American Heart Association quantifying cardiovascular health, and IR among nondiabetic populations in the United States. Methods and Results This cross‐sectional study used data on 11 246 nondiabetic adults aged ≥20 years from the 2005 to 2018 the National Health and Nutrition Examination Survey. The LE8 score was classified into 2 subscale scores: health factor score and health behavior score. IR was measured by homeostasis model assessment of insulin resistance (HOMA‐IR). Weighted logistic and linear regression models analyzed associations among the LE8 score, health behavior score, health factor score, and IR. Restricted cubic spline models assessed dose–response relationships. Adjusted subgroup analyses and inverse probability of treatment weighting method also evaluated the LE8‐IR relationship. Of the 11 246 participants, 4860 (43.2%) had IR. The mean LE8 score was 70.07 (95% CI, 69.57–70.58). In fully adjusted models, higher LE8 scores were associated with lower IR odds (odds ratio per 10‐unit increase, 0.57 [95% CI, 0.54–0.61]). Nonlinear LE8‐IR dose–response was observed. Similar patterns were seen for health behavior and health factor subscores, with stronger IR correlations for health factors. The inverse LE8‐IR association was significantly more pronounced among White participants and those with higher education, higher income, and without hypertension, cardiovascular disease, or chronic kidney disease. Significant negative LE8‐IR associations persisted after inverse probability of treatment weighting. Conclusions LE8 and subscale scores are negatively associated with IR in a nonlinear relationship. Promoting optimal cardiovascular health adherence may improve IR in nondiabetic populations