Blowing agent free generation of nanoporous poly(methylmethacrylate) materials

In this article, we demonstrate a newly developed technique for generation of nanoporous polymer materials. Generally, the production processes of polymeric nanostructured materials require high pressure due to the handling of gaseous blowing agents. Our new approach allows to generate nanoporous polymer materials without blowing agent at ambient conditions. Starting from a crosslinked polymer gel swollen with a mixture of at least two specially selected solvents leads to a nanoporous material by sequential evaporation. We varied the pore size of the generated structures between 80 and 800 nm so that the effect of the pore size on the gaseous thermal conductivity could be analyzed. Decreasing the pore size of the materials, the gaseous thermal conductivity could be reduced considerably. Thus, we developed a blowing agent free technique which allows the generation of nanoporous polymer materials-Knudsen materials-at an ambient pressure

Kinetics of pressure induced structural changes in super- or near-critical CO2-microemulsions

CO2-microemulsions show strong pressure dependent properties. Using time-resolved SANS to investigate the kinetics of structural changes upon periodic pressure jumps of adjustable amplitude, we found that the compression-induced formation of cylinders occurs on a timescale of one second, whereas the expansion-induced disintegration into CO2 swollen spherical micelles is much faster

Aorto-Left Ventricular Tunnel - Prenatal Diagnosis and Outcome

Purpose Aorto-left ventricular tunnel (ALVT) is an extremely rare, albeit prenatally detectable, extracardiac channel that connects the ascending aorta to the cavity of the left ventricle. Materials and Methods All ALVTs diagnosed prenatally (2006-2020) in five tertiary referral centers were retrospectively assessed for prenatal ultrasound findings, intrauterine course, postnatal outcome, and surgical treatment. We focused on the size of the tunnel and alterations of perfusion of the left ventricular outflow tract and aortic arch. Results 11 fetuses were diagnosed with ALVT at a mean gestational age of 24.8 weeks. All cases were associated with severe dilatation of the left ventricle and a to-and-fro flow in the left outflow tract. Signs of congestive heart failure were present in five fetuses, four of which were terminated and one of which died in the neonatal period. One fetus died in utero at 34 weeks without prior signs of cardiac failure. Of the five survivors, two underwent the Ross procedure. In both cases the prenatal left ventricular outflow was exclusively via a large tunnel. The remaining three neonates underwent patch closure of the tunnel. In these cases, the prenatal outflow of the left ventricle was via the aortic valve and simultaneously over the tunnel. Conclusion Prenatal diagnosis of ALVT should be considered in the presence of left ventricular hypertrophy, dilatation of the aortic root, and to-and-fro flow in the aortic outflow tract. Signs of heart failure are associated with an unfavorable outcome. Large tunnels, particularly in combination with the absence of flow over the aortic valve, may be an unfavorable predictor of surgical repair

Recommendations for Promoting Physical Activity for Children and Adolescents in Germany. A Consensus Statement

Increasing physical activity and reduction of sedentary behaviour play important roles in health promotion and prevention of lifestyle-related diseases in children and adolescents. However, the question of how much physical activity is useful for which target group is still a matter of debate. International guidelines (World Health Organization; European Association for the Study of Obesity), which are mainly based on expert opinions, recommend 60 min of physical activity every day. Age-and sex-specific features and regional differences are not taken into account. Therefore, expert consensus recommendations for promoting physical activity of children and adolescents in Germany were developed with special respect to national data, but also with respect to aspects of specific target groups, e. g., children with a lower socio-economic status (SES) or with migration background. They propose 90 min/day of physical activity, or at least 12,000 steps daily. Additionally, lifestyle factors, especially restriction of media consumption, were integrated. The recommendations provide orientation for parents and caregivers, for institutions such as schools and kindergartens as well as for communities and stakeholders. (C) 2014 S. Karger GmbH, Freibur

Recommendations for Promoting Physical Activity for Children and Adolescents in Germany. A Consensus Statement

Increasing physical activity and reduction of sedentary behaviour play important roles in health promotion and prevention of lifestyle-related diseases in children and adolescents. However, the question of how much physical activity is useful for which target group is still a matter of debate. International guidelines (World Health Organization; European Association for the Study of Obesity), which are mainly based on expert opinions, recommend 60 min of physical activity every day. Age- and sex-specific features and regional differences are not taken into account. Therefore, expert consensus recommendations for promoting physical activity of children and adolescents in Germany were developed with special respect to national data, but also with respect to aspects of specific target groups, e.g., children with a lower socio-economic status (SES) or with migration background. They propose 90 min/day of physical activity, or at least 12,000 steps daily. Additionally, lifestyle factors, especially restriction of media consumption, were integrated. The recommendations provide orientation for parents and caregivers, for institutions such as schools and kindergartens as well as for communities and stakeholders

Cardiac Rehabilitation in German Speaking Countries of Europe-Evidence-Based Guidelines from Germany, Austria and Switzerland LLKardReha-DACH-Part 1

Background: Although cardiovascular rehabilitation (CR) is well accepted in general, CR-attendance and delivery still considerably vary between the European countries. Moreover, clinical and prognostic effects of CR are not well established for a variety of cardiovascular diseases. Methods: The guidelines address all aspects of CR including indications, contents and delivery. By processing the guidelines, every step was externally supervised and moderated by independent members of the Association of the Scientific Medical Societies in Germany (AWMF). Four meta-analyses were performed to evaluate the prognostic effect of CR after acute coronary syndrome (ACS), after coronary bypass grafting (CABG), in patients with severe chronic systolic heart failure (HFrEF), and to define the effect of psychological interventions during CR. All other indications for CR-delivery were based on a predefined semi-structured literature search and recommendations were established by a formal consenting process including all medical societies involved in guideline generation. Results: Multidisciplinary CR is associated with a significant reduction in all-cause mortality in patients after ACS and after CABG, whereas HFrEF-patients (left ventricular ejection fraction <40%) especially benefit in terms of exercise capacity and health-related quality of life. Patients with other cardiovascular diseases also benefit from CR-participation, but the scientific evidence is less clear. There is increasing evidence that the beneficial effect of CR strongly depends on treatment intensity including medical supervision, treatment of cardiovascular risk factors, information and education, and a minimum of individually adapted exercise volume. Additional psychologic interventions should be performed on the basis of individual needs. Conclusions: These guidelines reinforce the substantial benefit of CR in specific clinical indications, but also describe remaining deficits in CR-delivery in clinical practice as well as in CR-science with respect to methodology and presentation