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Background/Objectives: Obesity and overweight have become increasingly prevalent in different populations of people with type 1 diabetes (PwT1D). This study aimed to assess the effect of body weight on glycaemic indices in PwT1D. Methods: Adult PwT1D using continuous glucose monitoring (CGM) and followed up at a regional academic diabetes centre were included. Body weight, body mass index (BMI), waist circumference, glycated haemoglobin (HbA1c), and standard CGM glycaemic indices were recorded. Glycaemic indices were compared according to BMI, and correlation and linear regression analysis were performed to estimate the association between measures of adiposity and glycaemic indices. Results: A total of 73 PwT1D were included (48% normal weight, 33% overweight, and 19% obese). HbA1c was 7.2% (5.6–10), glucose management indicator (GMI) 6.9% (5.7–8.9), coefficient of variation (CV) for glucose 39.5% ± 6.4, mean glucose 148 (101–235) mg/dL, TIR (time in range, glucose 70–180 mg/dL) 66% (25–94), TBR70 (time below range, 54–69 mg/dL) 4% (0–16), TBR54 (<54 mg/dL) 1% (0–11), TAR180 (time above range, 181–250 mg/dL) 20% ± 7, and TAR250 (>250 mg/dL) 6% (0–40). Glycaemic indices and achievement (%) of optimal glycaemic targets were similar between normal weight, overweight, and obese patients. BMI was associated negatively with GMI, mean glucose, TAR180, and TAR250 and positively with TIR; waist circumference was negatively associated with TAR250. Conclusions: CGM-derived glycaemic indices were similar in overweight/obese and normal weight PwT1D. Body weight and BMI were positively associated with better glycaemic control. PwT1D should receive appropriate ongoing support to achieve optimal glycaemic targets whilst maintaining a healthy body weight. [ABSTRACT FROM AUTHOR]

Background/Objectives: QRS fragmentation has not been linked with increased mortality in individuals without known cardiac disease. We aimed to investigate the physiological determinants of QRS fragmentation in individuals without cardiac disease. Methods: Study participants were 163 (54 athletes, 109 nonathletes) asymptomatic individuals with QRS fragmentation but without cardiac disease. QRS fragmentation was assessed in the supine position after deep inspiration or standing up and during exercise. The changes in QRS fragmentation were evaluated over a median follow-up period of 2.3 (0.8–4.9) years. Results: The most common lead with QRS fragmentation was III (63.0% in athletes, 61.5% in nonathletes), immediately followed by V1 (50.0%) and aVF (42.6%) in athletes and aVF (55.0%) in nonathletes. QRS fragmentation in V1 was more frequent in athletes compared to nonathletes (p < 0.001). Among athletes, the presence of QRS fragmentation in V1 could be independently predicted by increased RVOTproxi (right ventricular outflow tract proximal diameter indexed to body surface area) (p < 0.001). Among individuals with QRS fragmentation in V1, deep inspiration resulted in disappearance of QRS fragmentation more frequently in nonathletes compared to athletes (100% vs. 20%, p = 0.003). Deep inspiration resulted in disappearance of QRS fragmentation in aVF (p < 0.001). The presence of QRS fragmentation in II or aVF was associated with increased body mass index (BMI) (p = 0.003). Among athletes without QRS fragmentation in V1 at baseline, the appearance of QRS fragmentation in V1 at the end of follow-up was associated with greater training age (p = 0.034). Among individuals with QRS fragmentation in aVF at baseline, the disappearance of QRS fragmentation in aVF at the end of follow-up was associated with greater reduction in BMI (p = 0.008). Conclusions: The characteristic feature of QRS fragmentation in athletes was the presence of QRS fragmentation in V1, which was associated with RVOTproxi. The persistence of QRS fragmentation in V1 after deep inspiration could serve as a specific marker of exercise-training-related cardiac adaptation. The presence of QRS fragmentation in the leads of the frontal plane was influenced by BMI and respiration phase. [ABSTRACT FROM AUTHOR]

Hypoglycemia is common in patients with type 1 and type 2 diabetes (T1D, T2D), treated with insulin or sulfonylureas, and has multiple short- and long-term clinical implications. Whether acute or recurrent, hypoglycemia significantly affects the cardiovascular system with the potential to cause cardiovascular dysfunction. Several pathophysiological mechanisms have been proposed linking hypoglycemia to increased cardiovascular risk, including hemodynamic changes, myocardial ischemia, abnormal cardiac repolarization, cardiac arrhythmias, prothrombotic and proinflammatory effects, and induction of oxidative stress. Hypoglycemia-induced changes can promote the development of endothelial dysfunction, which is an early marker of atherosclerosis. Although data from clinical trials and real-world studies suggest an association between hypoglycemia and cardiovascular events in patients with diabetes, it remains uncertain whether this association is causal. New therapeutic agents for patients with T2D do not cause hypoglycemia and have cardioprotective benefits, whereas increasing the use of new technologies, such as continuous glucose monitoring devices and insulin pumps, has the potential to reduce hypoglycemia and its adverse cardiovascular outcomes in patients with T1D. [ABSTRACT FROM AUTHOR]

A synergistic interplay between vitamins K and D appears to exist. We aimed to investigate for the first time whether the associations of dietary vitamin K intake and circulating 25(OH)D with serum lipoprotein levels are influenced by the existence of deficiency of either or both vitamins K and D. Sixty individuals [24 males, 36(18–79) years old] were examined. Vitamin deficiency of K1 and D were defined as vitamin K1 intake/body weight (BW)<1.00 μg/kg/day and circulating 25(OH)D<20 ng/ml, respectively. In individuals with vitamin K1 deficiency, the vitamin K1 intake/BW correlated positively with high density lipoprotein-cholesterol (HDL-C) (r=0.509, p=0.008) and negatively with serum triglycerides (TG) (r=–0.638, p=0.001), whereas circulating 25(OH)D correlated negatively with TG (r=–0.609, p=0.001). In individuals with vitamin D deficiency, the vitamin K1 intake/BW correlated positively with HDL-C (r=0.533, p=0.001) and negatively with TG (r=–0.421, p=0.009), while circulating 25(OH)D correlated negatively with TG (r=–0.458, p=0.004). The above-mentioned associations of vitamin K1 intake/BW and circulating 25(OH)D with serum lipoproteins were not detected in individuals without vitamin K1 deficiency or the ones without vitamin D deficiency. The vitamin K2 intake/BW correlated negatively with low density lipoprotein-cholesterol (LDL-C) (r=–0.404, p=0.001). In conclusion, the associations of vitamin K1 intake with TG and HDL-C and of circulating 25(OH)D with TG were more pronounced in individuals with deficiency of either or both vitamins K1 and D. Increased dietary vitamin K2 intake was associated with decreased LDL-C. [ABSTRACT FROM AUTHOR]

Composite dowels are an economically and technically reasonable alternative to the conventional shear connectors, the headed studs. However, their competitiveness is limited by the fact that they are only approved nationally and for a limited period of time, whereas headed studs are firmly anchored in European regulations. Numerous investigations, performed on a national and international level for decades, were necessary in order to enable an integration of composite dowels into the European standards. This paper summarizes the extensive investigations on the influence of cracked concrete, of tensile and combined shear‐tensile loads as well as of composite dowel positions close to the surface on the load‐bearing behaviour of composite dowels. Based on these and former investigations, a consistent design concept for composite dowels was developed, which will also be presented within this paper and shall form the basis for the introduction into European standardization. [ABSTRACT FROM AUTHOR]

Fatigue design of composite girders and in particular shear connectors according to Eurocode 4 is based on fatigue strength curves. Therefore, the lifetime of a girder can be limited by failure of a critical shear connector. The failure probability of a component is thus determined by the failure probability of one shear stud or composite dowel, although a composite girder is an internally highly statically indeterminate system with the possibility of redistributing forces in the shear connection. This paper outlines the positive effects on the lifetime of a girder by considering crack propagation and residual capacity of shear connectors with cracks as well as redistributing forces towards less stressed and damaged connectors. The failure probability of a girder is determined by a Monte Carlo simulation using a lamella model with incremental calculation of the degradation of the shear connection. The results show the economic potential of a future global safety concept for composite girders especially with composite dowels. [ABSTRACT FROM AUTHOR]

Background: The physiological QT prolongation in athletes is expected to widen the gray zone between physiology and pathology of QT, increasing the diagnostic challenges encountered in athletes with QT prolongation. Summary: According to international recommendations for electrocardiogram in athletes, further evaluation for long QT syndrome (LQTS) is indicated in male athletes with corrected QT (QTc) ≥470 ms and in female athletes with QTc ≥480 ms. Apart from QTc ≥500 ms, diagnostic challenges arise in borderline cases of QTc prolongation, where further clinical investigations are needed to be performed to clarify whether LQTS exists. Clinical diagnostic investigations, including exercise testing, are more readily available, convenient, and easily interpretable, as well as less costly than genetic testing for LQTS. The main findings on exercise testing that are suggestive of LQTS can be the paradoxical prolongation of QTc during exercise and QTc ≥480 ms at fourth min of recovery. Key Messages: Exercise testing appears to have an important role in the diagnostic evaluation of athletes with prolonged QT interval, when genetic testing is not available. [ABSTRACT FROM AUTHOR]

Although previous studies suggest that prolonged intense exercise such as marathon running transitorily alters cardiac function, there is little information regarding ultramarathon races. Aim of this study was to investigate the acute impact of ultra-endurance exercise (UEE) on heart, applying advanced strain imaging. Echocardiographic assessment was performed the day before and at the finish line of "Spartathlon": A 246 Km ultra-marathon running race. 2D speckle-tracking echocardiography was performed in all four chambers, evaluating longitudinal strain (LS) for both ventricles and atria. Peak strain values and temporal parameters adjusted for heart rate were extracted from the derived curves. Out of 60 participants initially screened, 27 athletes (19 male, age 45 ± 7 years) finished the race in 33:34:27(28:50:38-35:07:07) hours. Absolute values of right (RV) and left ventricular (LV) LS (RVLS −22.9 ± 3.6 pre- to −21.2 ± 3.0% post-, p=0.04 and LVLS −20.9 ± 2.3 pre- to −18.8 ± 2.0 post-, p=0.009) slightly decreased post-race, whereas atrial strain did not change. RV and LV LS decrease was caused mainly by strain impairment of basal regions with apical preservation. Inter-chamber relationships assessed through RV/LV, LV/LA, RV/RA and RA/LA peak values' ratios remained unchanged from pre to post-race. Finally, UEE caused an extension of the systolic phase of cardiac cycle with concomitant diastole reduction (p<0.001 for all strain curves). Conclusively, ventricular LS strain as well as effective diastolic period slightly decreased, whereas atrial strain and inter-chamber relationships remained unchanged after running a 246-km-ultra-marathon race. These changes may be attributed to concomitant pre- and afterload alterations following UEE. [ABSTRACT FROM AUTHOR]

Experimental investigations on centrically loaded column bases provide the basis for current punching shear design provisions. However, this symmetric loading condition represents an exception in daily engineering practice since usually load eccentricities occur leading to uneven shear stress distributions along the control perimeter. To account for this effect, design approaches define different factors to either increase the acting shear force or to decrease the punching shear resistance in design. New punching test results of 14 eccentrically loaded and four centrically loaded column bases now allow the evaluation of design approaches depending on different geometric boundary conditions. In this new test series, the load eccentricities were systematically graded to analyze their influence on the punching behavior. Strain measurements in the multiaxial compression zone of the concrete in the column‐footing connection reveal new insights on the punching failure of column bases. As a result, a correlation between tangential concrete strains and the reduction of punching shear strength can be recognized for increasing load eccentricities. The comparison of experimentally determined load increase factors with the design results according to Eurocode 2, Model Code 2010 and the stable version of the next generation of Eurocode 2 reveals optimization potential for deriving more advanced design provisions in the future. [ABSTRACT FROM AUTHOR]

The overwhelming majority of sports-related sudden cardiac deaths in mature athletes is attributed to coronary artery disease (CAD). Coronary plaques of mature athletes appear to be more calcified compared to sedentary individuals and thus may be more stable and less likely to be associated with an acute coronary event. Cardiac computed tomography (CT), including unenhanced CT for coronary artery calcium scoring (CACS) and contrast-enhanced coronary CT angiography, is characterized by very high negative predictive value to rule out CAD. Cardiac CT has been shown to have additional diagnostic value for detection of CAD in athletes over and above exercise electrocardiogram. Moreover, measurement of CACS possibly enables a more precise cardiovascular risk stratification of mature athletes. The main advantage of cardiac CT is its noninvasive nature. Although cardiac CT appears to increase the overall cost of cardiac examinations, this additional cost is much lower than the cost of unnecessary invasive coronary angiographies that would be performed in case of false positive results of exercise electrocardiograms. Radiation exposure may not be a major concern for the application of this modality to pre-participation screening of athletes, since recent technical advancements have resulted in low radiation dose of cardiac CT. Highlights Coronary computed tomography angiography can be used in pre-participation screening of mature athletes to increase the negative predictive value for excluding coronary artery disease. The identification of coronary artery calcium score = 0 in an athlete can improve risk stratification, since this athlete can be reasonably managed as an individual with low cardiovascular risk. [ABSTRACT FROM AUTHOR]

The importance of slim decks has led engineers to the exploration of high-strength materials and also of innovative shallow shear connectors, such as composite dowels in the case of composite constructions. Minimizing the overall slab depth often leads to composite girders being weakened by means of web openings that are necessary for installations such as ventilation ducts. Depending on the geometrical and loading conditions, some of the shear connectors are subjected to a combination of tensile and shear forces. However, the load-bearing behaviour of these connectors has only been rudimentarily investigated in the case of shear-tensile interaction. In addition, the load-bearing capacity of composite dowels under combined tensile and shear forces has not been investigated in cracked concrete. Earlier investigations under pure shear and pure tensile loading indicate a dependence of the connectors' load-bearing behaviour on the crack width, so that under combined loading, a similar influence is expected. In this paper, experimental investigations on composite dowels in transversely cracked concrete under systematically varied shear-tension loading combinations are presented. Hereby, predefined crack widths and patterns were considered using a special test rig. Finally, a design approach for concrete failure of composite dowels under shear-tension loading is proposed based on the test results. [ABSTRACT FROM AUTHOR]

There is little research about the effects of ultra-endurance exercise on arterial morphological and functional properties. The aim was to assess the acute changes of the carotid-femoral pulse wave velocity and carotid doppler-derived parameters following an ultra-marathon race as well as the intima-media thickness of the carotid artery in ultra-marathon runners. Twenty athletes were examined at baseline and within 10 mins after a 246 km running race. Measurements included carotid-femoral pulse wave velocity, peak-systolic and end-diastolic velocities of carotid artery blood flow, pulsatility and resistivity indices and blood biochemical parameters. The intima-media thickness of the right and left carotid artery was measured before the race. Arterial stiffness and carotid artery intima media thickness at rest remained within known normal limits. The ultra-marathon race significantly increased carotid-femoral pulse wave velocity by 22.6% and pulsatility index by 10.2%. There was a decrease in body weight by 3.35% and an increase of all biochemical markers of muscle damage after the race. Additionally, C-reactive protein was correlated with both pulsatility and resistivity indices post-race. This study shows that immediately after a 246 km ultra-marathon running race, acute increase of arterial stiffness and vascular resistance were evident. The carotid artery thickness of ultra-marathon runners was within normal range. [ABSTRACT FROM AUTHOR]

Aim: We aimed to investigate the main anthropometric, cardiorespiratory and haematological factors that can determine marathon race performance in marathon runners. Methods: Forty-five marathon runners (36 males, age: 42 ± 10 years) were examined during the training period for a marathon race. Assessment of training characteristics, anthropometric measurements, including height, body weight (n = 45) and body fat percentage (BF%) (n = 33), echocardiographic study (n = 45), cardiopulmonary exercise testing using treadmill ergometer (n = 33) and blood test (n = 24) were performed. We evaluated the relationships of these measurements with the personal best marathon race time (MRT) within a time frame of one year before or after the evaluation of each athlete. Results: The training age regarding long-distance running was 9 ± 7 years. Training volume was 70 (50–175) km/week. MRT was 4:02:53 ± 00:50:20 h. The MRT was positively associated with BF% (r = 0.587, p = 0.001). Among echocardiographic parameters, MRT correlated negatively with right ventricular end-diastolic area (RVEDA) (r = −0.716, p < 0.001). RVEDA was the only independent echocardiographic predictor of MRT. With regard to respiratory parameters, MRT correlated negatively with maximum minute ventilation indexed to body surface area (VEmax/BSA) (r = −0.509, p = 0.003). Among parameters of blood test, MRT correlated negatively with haemoglobin concentration (r = −0.471, p = 0.027) and estimated haemoglobin mass (Hbmass) (r = −0.680, p = 0.002). After performing multivariate linear regression analysis with MRT as dependent variable and BF% (standardised β = 0.501, p = 0.021), RVEDA (standardised β = −0.633, p = 0.003), VEmax/BSA (standardised β = 0.266, p = 0.303) and Hbmass (standardised β = −0.308, p = 0.066) as independent variables, only BF% and RVEDA were significant independent predictors of MRT (adjusted R2 = 0.796, p < 0.001 for the model). Conclusions: The main physiological determinants of better marathon performance appear to be low BF% and RV enlargement. Upregulation of both maximum minute ventilation during exercise and haemoglobin mass may have a weaker effect to enhance marathon performance. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT04738877. [ABSTRACT FROM AUTHOR]

Fatigue of a composite girder according to Eurocode 4 is carried out on the decisive shear connector. It is not taken into account that the composite girder is an internally highly statically indeterminate system in which the failure of a dowel does not necessarily lead to the failure of the girder. This applies in particular to composite dowels which are characterised by a crack propagation phase with a high residual load‐bearing capacity of a damaged dowel. In own small part and girder tests as well as numerical studies, numerous positive load‐bearing effects could be identified in composite girders with composite dowels, which increase the lifetime of the girder. In case of an initial crack in a steel dowel, followed by crack propagation, the stiffness degradation of the damaged connector leads to a redistribution of forces. The lifetime of a girder is limited by the residual capacity of the composite joint or by a global failure with increasing partial connection. A global safety concept for composite girders taking into account the crack development and residual strength of the dowels as well as the redistribution of forces within the composite joint holds an enormous economic potential. This article shows how these effects can be taken into account. [ABSTRACT FROM AUTHOR]

Composite dowels as shear connectors between steel profiles and concrete sections have been investigated for decades. The long‐term aim is to implement a consistent design concept within Eurocode 4 ‐ covering both, the fields of bridge and building construction. Especially in building construction, where the concrete slabs are dimensioned increasingly slimmer in contrast to bridge construction, the composite dowels are positioned unavoidably close to free concrete surfaces. This causes additional failure modes, leading to the overall failure of the structure, which have not been entirely investigated yet. At University of Kaiserslautern more than 30 push‐out tests were performed within a joint research project in cooperation with RWTH Aachen University. These tests were focused on the resistance of composite dowels close to the concrete surface in dependence of varying influence parameters. Some results showed a significant reduction in shear strength and deformation capacity, mostly accompanied by the spalling of the concrete cover. Simultaneously, numerical simulations were calibrated and utilized to get a deeper understanding of the load transfer mechanisms and to interpolate between existing experimental results. On the basis of experimental measurements and numerical simulations a load transfer model was developed with a corresponding design approach to calculate the theoretical resistance. [ABSTRACT FROM AUTHOR]

Introduction: Myopathy is possibly the most clinically relevant statin-induced side effect. Case Presentation: We report a case of a 63-year-old healthy male with mixed dyslipidemia. He developed bilateral myalgia of the forearms with fluvastatin 40 mg/day, pravastatin 20 mg/day, and combination of atorvastatin 10 mg and ezetimibe 10 mg/day. The only hypolipidemic treatment that was tolerable was the combination of pitavastatin 1 mg and ezetimibe 10 mg/day. Discussion: Pitavastatin demonstrated less potential for the development of myalgia compared to the so far considered most tolerable statins (i.e., fluvastatin and pravastatin). All the tested statins were used at the lowest approved dose for clinical use. Conclusion: The combination of pitavastatin 1 mg and ezetimibe appears to be a promising treatment choice for individuals who are intolerant to statin therapy due to muscle complaints. [ABSTRACT FROM AUTHOR]

Fatigue of rib shear connectors – Analysis and engineering model The use of composite dowel shear connectors is becoming increasingly important in both building and bridge constructions. In addition to the high load‐bearing capacity and stiffness of the composite dowels, their significantly better load‐bearing behaviour under cyclic loading compared to headed studs is one further important advantage. As a result, the use of these innovative shear connectors in bridge construction is particularly promising. However, the existing regulations for the fatigue design of composite dowels were chosen conservatively due to the low experimental data basis, so that the advantageous cyclic load‐bearing behaviour cannot yet be fully deployed. Within the scope of this article, the load bearing behaviour of composite dowels under cyclic loading is analysed in detail on the basis of experimental findings. Based on this, a model for estimating the service life of the composite dowels is developed. [ABSTRACT FROM AUTHOR]