Publications by authors named "Welz A"

Poor workability is a common feature of calcium sulfoaluminate (CSA) cement paste. Multiple chemical admixtures, such as set retarders and dispersants, are frequently employed to improve the workability and delay the setting of CSA cement paste. A quantitative assessment of the compatibility, efficiency, and the effects of the admixtures on cement paste workability is critical for the design of an appropriate paste formulation and admixture proportioning.

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Recreational use of piperazine designer drugs is a serious threat to human health. These compounds act on the body in a similar fashion to illegal drugs. They induce psychostimulatory effects as well as visual and auditory hallucinations to varying degrees.

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Background: Intraoperative and postoperative bleeding associated with allogeneic blood transfusion and reoperation is still a common and feared complication in patients undergoing surgery due to acute Type A Aortic Dissection (aTAAD). The aim of our study was to identify risk factors for higher transfusion rates.

Methods: In this retrospective single center study we evaluated pre -, intra-, and postoperative data of 121 patients with aTAAD.

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Piperazine derivatives belong to the popular psychostimulating compounds from the group of designer drugs. They are an alternative to illegal drugs such as ecstasy and amphetamines. They are being searched by consumers for recreational use due to their stimulating and hallucinogenic effects.

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Background: Physiotherapy prior to open-heart surgery lowers the rate of pneumonia and length of the hospital stay. Pneumonia is a major contributor to short-term mortality following transcatheter aortic valve replacement (TAVR). Hence, we hypothesized that pre- and intensified postprocedural physiotherapy in patients undergoing TAVR might impact the net functional and clinical outcome.

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The performance of adsorbents prepared by alkali activation of high calcium fly ash was investigated for removing aqueous Zn. Two formulations involving the use of NaOH and NaSiO activating solutions were used to prepare the adsorbents that feature different microstructural characteristics. The Zn sorption data indicates a sorption process that is controlled by both chemisorption and intra-particle diffusion.

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Objectives: The aim of this was to analyse current outcomes in patients referred to coronary artery bypass grafting (CABG) for acute coronary syndromes (ACSs), including ST-elevation or non-ST-elevation ACS (non-ST-segment elevation myocardial infarction) or unstable angina.

Methods: Patients (n = 2432) undergoing CABG for ACS between January 2010 and December 2017 were prospectively entered into a surgical myocardial infarction registry in North Rhine-Westphalia, Germany. Key end points were in-hospital all-cause mortality (IHM) and major adverse cardio-cerebral events (MACCE).

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The geopolymer-an inorganic polymeric material synthesized from the reaction of aluminosilicate precursors and alkaline activating solutions-has gained wide research attention in recent decades as a promising adsorbent for the removal of aqueous heavy metals. However, the high variability of the material and several unanswered questions have limited its development and general adoption in the industry. This study evaluates the impacts of composition and microstructure on the performance of geopolymers for aqueous lead (Pb) removal to elucidate the composition-structure-property relationship.

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Piperazine derivatives are a group of compounds with a psychostimulant effect. They are an alternative to illegal drugs. They are being searched for recreational use due to their psychoactive and hallucinogenic effects.

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Background: Transcatheter aortic valve replacement (TAVR) is an alternative treatment option to surgical aortic valve replacement (SAVR) in selected high-risk patients. In this study, we aimed to evaluate the prognostic value of right ventricular (RV) functional imaging to predict clinical response to TAVR and SAVR.

Methods: One hundred and ten patients with symptomatic severe aortic valve stenosis (AVS) undergoing successful TAVR and 32 controls undergoing SAVR were prospectively enrolled.

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Background: Prevalence rates for herbal medicine (HM) have been increasing worldwide. However, little is known about prevalence, user characteristics, usage pattern and factors influencing HM usage for the general German population.

Methods: A nationwide online survey on HM usage was conducted in Germany.

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Indications for TF-TAVI (transfemoral transcatheter aortic valve implantation) are rapidly changing according to increasing evidence from randomized controlled trials. Present trials document the non-inferiority or even superiority of TF-TAVI in intermediate-risk patients (STS-Score 4-8%) as well as in low-risk patients (STS-Score < 4%). However, risk scores exhibit limitations and, as a single criterion, are unable to establish an appropriate indication of TF-TAVI vs transapical TAVI vs SAVR (surgical aortic valve replacement).

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Background: The use of herbal medicine (HM) has become an essential form of treatment and it is more and more common around the world. Little is known about the reasons that drive people to initially use HM or to maintain their behaviour, and whether the so-called "push and pull factors" known in the context of decision making for complementary and alternative medicine, also play a role for HM use. Here, our goal was to provide answers to these open questions and to analyse the reasons that motivate new, established and long-term HM consumers in detail.

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Background Coronary artery bypass grafting for acute coronary syndrome complicated by cardiogenic shock ( CS ) is associated with a high mortality. This registry study aimed to distinguish between early surgical outcomes of CS patients with non- ST -segment-elevation myocardial infarction ( NSTEMI ) and ST -segment-elevation myocardial infarction ( STEMI ). Methods and Results Patients with NSTEMI (n=1218) or STEMI (n=618) referred for coronary artery bypass grafting were enrolled in a prospective multicenter registry between 2010 and 2017.

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The use of left-ventricular (LV) hemodynamic support might facilitate high-risk percutaneous coronary interventions (PCI) in patients with complex coronary artery disease. The impact on outcome is a matter of ongoing debate. We assessed the outcome of high-risk patients who underwent protected PCI in comparison to patients who underwent unprotected high-risk PCI.

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Objectives: Surgery of thoracic aortic aneurysm (TAA) is associated with blood loss and coagulopathy and a high need for red blood cell (RBC) volume. Retrograde autologous priming (RAP) decreases haemodilution during cardiopulmonary bypass (CPB). The aim of this study was to show the effect of RAP during surgery of TAA repair on haemodilution, the need for RBC transfusion and the postoperative course compared to conventional CPB (cCPB).

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Ventricular tachycardia (VT) is the most common and potentially lethal complication following myocardial infarction (MI). Biological correction of the conduction inhomogeneity that underlies re-entry could be a major advance in infarction therapy. As minimal increases in conduction of infarcted tissue markedly influence VT susceptibility, we reasoned that enhanced propagation of the electrical signal between non-excitable cells within a resolving infarct might comprise a simple means to decrease post-infarction arrhythmia risk.

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Background: The use of herbal medicine, as one element of complementary and alternative medicine, is increasing worldwide. Little is known about the reasons for and factors associated with its use. This study derives insights for the use of herbal medicine in Germany regarding the usage aims, role played by the type of illness, reasons for preferred usage and sources of information.

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Cell replacement in the heart is considered a promising strategy for the treatment of post-infarct heart failure. Direct intramyocardial injection of cells proved to be the most effective application route, however, engraftment rates are very low (<5%) strongly hampering its efficacy. Herein we combine magnetic nanoparticle (MNP) loading of EGFP labeled embryonic cardiomyocytes (eCM) and embryonic stem cell-derived cardiomyocytes (ES-CM) with application of custom designed magnets to enhance their short and long-term engraftment.

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Objectives: The German Aortic Valve Score (GAVS) was developed for national quality assurance regarding the in-hospital mortality rate of patients following isolated aortic valve replacement. The goal of this work was the recalibration of the GAVS in the context of increased numbers of transcatheter aortic valve implantations.

Methods: In 2011 and 2012, 36 183 cases were documented who had either surgical aortic valve replacement or transcatheter aortic valve implantation (45%).

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People's minds frequently wander towards self-generated thoughts, which are unrelated to external stimuli or demands. These phenomena, referred to as "spontaneous thought" (ST) and "mind wandering" (MW), have previously been linked with both costs and benefits. Current assessments of ST and MW have predominantly been conducted in the laboratory, whereas studies on the ecological validity of such lab-related constructs and their interrelations are rare.

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Cardiovascular disease and in particular, heart failure are still main causes of death; therefore, novel therapeutic approaches are urgently needed. Loss of contractile substrate in the heart and limited regenerative capacity of cardiomyocytes are mainly responsible for the poor cardiovascular outcome. This is related to the postmitotic state of differentiated cardiomyocytes, which is partly due to their polyploid nature caused by cell cycle variants.

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