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In the Late Permian Zechstein Sea of Central Europe, up to 2000 m of evaporitic rocks were deposited in at least four consecutive cycles. The age of these evaporitic rocks could not yet be precisely determined, because they are virtually fossil-free and do not contain radiometrically datable volcanic layers. A chemostratigraphic age of the succession can be determined by comparing 87Sr/86Sr ratios of marine gypsum and anhydrite to the worldwide marine strontium evolution curve. Unfortunately, published 87Sr/86Sr data of the Zechstein succession are characterized by frequent outliers towards higher ratios, making an age assignment challenging. The scatter in 87Sr/86Sr ratios might be induced by different processes like the contribution of meteoric water to the brine, in-situ Rb decay, or post-depositional hydrothermal or diagenetic overprint. Here, we present a dataset of 26 new gypsum and anhydrite 87Sr/86Sr ratios from drill cores situated at "Alter Stolberg" in the northernmost Thuringian Basin. Evaporites of the Werra-, Staßfurt-, and Leine cycles were sampled. The close proximity of the drillings allows a very accurate assignment of the stratigraphic position of each sample, so that trends and outliers in 87Sr/86Sr ratios can easily be recognized. While the entire Werra Formation obviously revealed non-marine 87Sr/86Sr ratios, the lowermost 87Sr/86Sr ratios in the Staßfurt and Leine Formations can be assumed to represent marine ratios and allow estimating a chemostratigraphic age of 257‒254 Ma. The combination of the 87Sr/86Sr data with the mineral composition of the samples suggests a contribution of meteoric water, probably river water, to the Zechstein Sea as the main reason for the observed increase in 87Sr/86Sr ratios. Additional in-situ Rb decay, related to the riverine input of clay minerals, cannot be excluded. Modelling the amounts of sea water and meteoric water in the brine indicates that 83‒99% of meteoric water would be necessary to explain the highest 87Sr/86Sr ratios observed in the Werra Formation. [ABSTRACT FROM AUTHOR]

Pump thrombosis is a major complication of CF LVAD therapy, affecting approximately 5% of HVAD (HeartWare) patients. We report a 76-year-old male with stage D congestive heart failure and three years of HVAD destination therapy experiencing a low-flow alert. Echocardiography revealed insufficient LV unloading. A lowered average flow of 1.98 L/min was observed, and power consumption remained at 3.1 Watts at 2700 rpm. No changes in the acoustic signal and an absence of hemolysis evidence in the serum workup. CT angiography showed LV dilatation with no outflow cannula thrombosis or stenosis and was negative for pulmonary embolism.Therefore, a pre-pump thrombus was suspected. For destination therapy, patients' pump exchange is the gold standard for managing LVAD thrombosis. As the HVAD was not available at this moment, pump exchange with the HeartMate 3 (HM3) appeared not practicable in this sick patient. Hence, a retrograde thrombus washout maneuver was performed while the patient was awake and spontaneously breathing: With vasopressors, mean blood pressure was raised to 100 mmHg, and ventricular contractility was improved with intravenous adrenaline. The pump was turned off for 10 seconds while manually squeezing carotid arteries in Trendelenburg's position to avoid cerebral thromboembolism. After restarting the pump, the parameters reverted to normal, with a flow of 4.2 L/min and a power of 4.1 Watts at 2700 rpm.The patient had no perfusion or neurological abnormalities during or after the procedure. Pre-pump, intra-pump, and post-pump flow obstructions can occur as HVAD flow obstructions (Figure 1). Pump exchange remains the gold standard for managing LVAD thrombosis, but the invasiveness of the surgery disqualifies some patients: In particular, the exchange of an HVAD pump in the current era involves not only medical and surgical obstacles but also a logistical dilemma, as Medtronic terminated the distribution and sale of the HVAD system on June 3, 2021. [ABSTRACT FROM AUTHOR]

This article, published in the journal Thoracic & Cardiovascular Surgeon, explores the predictive value of the preoperative right-to-left ventricular filling pressures (CVP/PCWP) ratio on the development of right-sided heart failure (RSHF) after left ventricular assist device (LVAD) implantation. The study analyzed data from 134 patients who received a continuous flow LVAD with a centrifugal pump, with 40 patients initially evaluated using a right-sided heart catheter. The results showed that a high CVP/PCWP ratio was associated with a higher incidence of RSHF after LVAD implantation. The study suggests that monitoring the CVP/PCWP ratio could help predict the risk of RSHF and guide treatment decisions. [Extracted from the article]

Abstract: After an accidental radioactive contamination by aerosols in inhabited areas, the radiation exposure to man is determined by complex interactions between different factors such as dry or wet deposition, different types of ground surfaces, chemical properties of the radionuclides involved and building development as well as dependence on bomb construction e.g. design and geometry. At short-term, the first rainfall is an important way of natural decontamination: deposited radionuclides are washed off from surfaces and in urban areas the resulting contaminated runoff enters the sewer system and is collected in a sewage plant. Up to now the potential exposure caused by this process has received little attention and is estimated here with simulation models. The commercial rainfall-runoff model for urban sewer systems KANAL++ has been extended to include transport of radionuclides from surfaces through the drainage to various discharge facilities. The flow from surfaces is modeled by unit hydrographs, which produce boundary conditions for a system of 1d coupled flow and transport equations in a tube system. Initial conditions are provided by a map of surface contamination which is produced by geo-statistical interpolation of γ-dose rate measurements taking into account the detector environment. The corresponding methodology is implemented in the Inhabited Area Monitoring Module (IAMM) software module as part of the European decision system JRODOS. A hypothetical scenario is considered where a Radiation Dispersal Device (RDD) with Cs-137 is detonated in a small inhabited area whose drainage system is realistically modeled. The transition of deposited radionuclides due to rainfall into the surface runoff is accounted for by different nuclide-specific entrainment coefficients for paved and unpaved surfaces. The concentration of Cs-137 in water is calculated at the nodes of the drainage system and at the sewage treatment plant. The external exposure to staff of the treatment plant is estimated. For Cs-137 radiation levels in the plant are low since wash-off of cesium from surfaces is an ineffective process. [Copyright &y& Elsevier]

The correct prediction of flooding in urban areas is an important challenge to secure the values and fulfil public regulations. Traditional sewer simulations deliver the basic information for a rudimental flood protection, but the interaction between sewer and surface runoff can only be considered by a bi-directional modelling. Therefore detailed information about the relevant structures on the surface is necessary, which can partially be delivered by airborne laser scan data. This data have to be refined to get as detailed information about the endangered areas as possible. But the plenitude of information leads to high requirements on computer capacity and performance. This paper shows different approaches to predict the sewer caused flooding in urban areas. The approaches have been checked on two testing areas in Germany and the developed tool will be implemented in a commercial software system soon. This approaches, which partially base on each other, make a stepwise refinement of the model and narrowing of the affected areas possible. The developed algorithms to thin the digital terrain model and the well proven method to parallelize the calculation on more than one processing units secure an effective calculating process. [ABSTRACT FROM AUTHOR]

Purpose Cardiac recovery after mechanical circulatory support allows explantation of the left ventricular assist device (LVAD). So far, no FDA approved or CE certified plug is available for the explantation of newest generation HeartMate 3TM. Here, we present an individualized explantation strategy with an in-house developed patient-tailored silicone plug for the HeartMate 3™ LVAD avoiding (re-) sternotomy. Methods Hemodynamic evaluation of two HeartMate 3TM patients was performed in order to assess cardiac recovery and hereby planning a LVAD explantation strategy avoiding (re-) sternotomy. A preoperative CT scan was used to define the ideal dimensions of the silicone plug fitting with a HeartMate 3TM mock apical ring. The cylindrical plug was made out of medical grade liquid silicone elastomer MED-4820 (NuSil Silicone Technology LLC, Carpinteria, USA) using a patient specific high quality surface casting mold and subsequently sterilized in a clinical standard process. Its geometry was defined by the inner diameter of the apical cuff and the patient's CT data implementing one rounded end and a cylindrical head with cross-shaped suture guides on the other end. Results Following CT scans of two HeartMate 3TM patients, individualized explantation of the LVAD was planned with a patient-tailored silicone plug. Both patients could be successfully weaned from VAD support and explanted with a lateral thoracotomy. No apical bleeding occurred after VAD removal and silicone plug insertion. The plugs could be inserted easily and reliably secured with crossing sutures. The patients were monitored on ICU and could be discharged home in the following days. Conclusion The surgical removal of HeartMate 3TM is feasible using a patient-tailored silicone plug avoiding (re-) sternotomy. The medical grade liquid silicone elastomer allows perfect patient-specific fitting with pre-operative CT-measured dimensions. [ABSTRACT FROM AUTHOR]