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While Wilms tumors (WT) typically present solely with an abdominally palpable mass, rare cases exhibiting vascular tumor growth can also present with circulatory problems. Here, we report the case of a 2.5-year-old girl presenting with upper venous congestion and arterial hypertension as the primary symptoms of intraventricular tumor growth exhibiting remarkable tubular and perfused morphology. Clinical situation stabilized after initiation of neoadjuvant chemotherapy (NAC) with actinomycin D and vincristine, followed by surgical resection via laparotomy and sternotomy supported by cardiopulmonary bypass and deep hypothermia. Our results highlight the previously reported feasibility of this approach, even in primarily unstable patients.

Introduction Congenital heart surgery with cardiopulmonary bypass (CPB) initiates an immune response which frequently leads to organ dysfunction and a systemic inflammatory response. Complications associated with exacerbated immune responses may severely impact the postoperative recovery. The objective was to describe the characteristics of monocyte subpopulations and neutrophils at the level of pattern recognition receptors (PRR) and the cytokine response after CPB in infants. Methods An observational cohort study was conducted between June 2016 and June 2017 of infants Results Samples from 21 infants (median age 7.4 months) were analyzed by flow cytometry and from 11 infants, cytokine concentrations were measured. Classical and intermediate monocytes showed first receptor upregulation with an increase in CD64 expression four hours post CPB. CD64–expression on intermediate monocytes almost tripled 48 h post CPB (p TLR4 expression on intermediate monocytes correlated with vasoactive-inotropic score (rs = 0.642, p = 0.0017), duration of ventilation (rs = 0.485, p = 0.0259), highest serum creatinine (rs = 0.547, p = 0.0102), postsurgical transfusion (total volume per kg bodyweight) (rs = 0.469, p = 0.0321) and lowest mean arterial pressure (rs = -0.530, p = 0.0135). Concentrations of IL-10, MIP-1β, IL-8, G–CSF and IL-6 increased one hour post CPB. Methylprednisolone administration in six patients had no significant influence on the studied surface receptors but led to lower IL-8 and higher IL-10 plasma concentrations. Conclusions Congenital heart surgery with CPB induces a systemic inflammatory process including cytokine response and changes in PRR expression. Intermediate monocytes feature specific inflammatory characteristics in the 48 h after pediatric CPB and TLR4 correlates with poorer clinical course, which might provide a potential diagnostic or even therapeutic target.

Background: Depth of anesthesia may be insufficient in pediatric cardiac anesthesia if a total intravenous anesthetic regimen with opioids and midazolam is used during cardiopulmonary bypass. The advantages of sevoflurane-based balanced anesthesia may be (1) a more graduated regulation of the depth of anesthesia during cardiopulmonary bypass and (2) a reduction in postoperative ventilation time for children in comparison with total intravenous anesthesia. Aim: To evaluate a possibly positive effect of sevoflurane-based balanced anesthesia in children undergoing cardiac surgery we analyzed whether this anesthetic regimen had a significant effect related to (1) depth of anesthesia, (2) the need for opioids during cardiopulmonary bypass as well as on postoperative characteristics such as (3) time of postoperative ventilation, and (4) duration of stay in the intensive care unit in comparison with total intravenous anesthesia. Methods: In a retrospective analysis, data from heart-lung machine protocols from 2013 to 2016 were compared according to anesthetic regimen (sevoflurane-balanced anesthesia, n = 70 vs. total intravenous anesthesia, n = 65). Children (age: 8 weeks to 14 years) undergoing cardiac surgery with cardiopulmonary bypass were included. As a primary outcome measure, we compared Narcotrend® system–extracted data to detect insufficient phases of anesthetic depth during extracorporeal circulation under moderate hypothermia. Postoperatively, we measured the postoperative ventilation time and the number of days in the intensive care unit. Furthermore, we analyzed patients’ specific characteristics such as opioid consumption during cardiopulmonary bypass. Regression analysis relating primary objectives was done using the following variables: anesthetic regimen, age, severity of illness/surgery, and cumulative dosage of opiates during cardiopulmonary bypass. Results: No significant differences were observed in descriptive patient characteristics (age, body weight, height, and body temperature) between the two groups. Further, no significant differences were found in depth of anesthesia by analyzing phases of superficial B1-C2-electroencephalography Narcotrend® data. No marked difference between the groups was observed for the duration of postoperative intensive care unit stay. However, the postoperative ventilation time (median (95% CI, hours)) was significantly lower in the sevoflurane-based balanced anesthesia group (6.0 (2.0-15.0)) than in the total intravenous anesthesia group (13.5 (7.0-25)). A higher dosage of opioids and midazolam was required in the total intravenous anesthesia group to maintain adequate anesthesia during cardiopulmonary bypass. Regression analysis showed an additional, significant impact of the following factors: severity of illness and severity grade of cardiac surgery (according to Aristotle) on the primary endpoint. Conclusion: In children undergoing cardiac surgery in our department, the use of sevoflurane-balanced anesthesia during cardiopulmonary bypass showed no superiority of inhalational agents over total intravenous anesthesia with opioids and benzodiazepines preventing phases of superficial anesthesia, but a marked advantage for the postoperative ventilation time compared with total intravenous anesthesia.

The absorption cross section of natural Gd and isotopic enriched 157 Gd for ultra-cold neutrons (UCN) as a function of the velocity has been measured within a time-of-flight-experiment. Particular attention is paid to small velocities in the region of a few m/s. This is intended to determine the validity of the 1 / v -law governing absorption cross sections in this region and the resulting divergence at v = 0 . The experiment does not show any significant violation of 1 / v for v > 3 m / s .

Infection is the most common cause of death in hemodialysis patients after cardiovascular complications. The long-term use of venous catheters for dialysis elevates the risk. Valvular calcification is of special concern in developing infective endocarditis and is often found in chronic dialysis patients. The right-sided endocarditis is rarely reported in the literature and may be overseen until the development of further complications. In our case tricuspid valve endocarditis, with severe insufficiency and stenosis due to a calcified laminar plate was found in a 57-year-old female patient undergoing dialysis due to end-stage renal disease. The calcification aroused from the tip of the dual lumen tunneled venous catheter used for routine dialysis. We replaced the tricuspid valve with mechanical valve prosthesis and reconstructed the right atrium.

Background: Successful surgical repair of a regurgitant mitral valve (MV) is dependent on a comprehensive assessment of its complex anatomy. Although there is limited evidence of the feasibility and accuracy of intraoperative real-time 3-dimensional transesophageal echocardiography (RT3DTEE) in MV surgery, its use is increasing worldwide. We designed this prospective observational study of patients with mitral regurgitation to test initial findings on the accuracy of RT3DTEE images in the diagnosis of MV prolapse and chordal rupture relative to 2D imaging and to assess the potential of RT3DTEE for visualizing leaflet clefts. Methods: TEE-certified anesthesiologists examined 62 consecutive patients undergoing MV surgery by acquiring a full standard set of 2D TEE sections and 3D zoom recordings. Offline, 2D and 3D images were presented independently and in randomized order to 2 expert interpreters. Accuracy was determined using the surgical findings as the “gold standard.” Results: Surgical inspection identified 52 cases of MV prolapse (MVP). RT3DTEE correlated stronger with the surgical findings than 2D TEE for detection and localization of MVP (difference in proportions = 33.9%, P < 0.001) and chordal rupture (difference in proportions = 25.8%, P < 0.001). The superiority of RT3DTEE was significant for scallops A2, P1, P2 in MVP and A2, P2 in chordal rupture (all P < 0.05). In 22 patients, leaflet clefts were also surgically repaired, and RT3DTEE was feasible in accessing them (κ = 0.65, confidence interval [0.44, 0.81]). Conclusion: Although 2D TEE is currently the standard tool for intraoperative imaging in MV surgery, RT3DTEE improves the visualization of MV pathology and increases the accuracy of interpretation by facilitating spatial orientation. Further investigations, particularly those aimed at establishing its cost effectiveness, are indicated.

Neutrons are proper tools for testing basic laws of quantum physics since they are massive and can be handled and measured with high efficiency. Suitable post-selection experiments demonstrate coherence features of sub-ensembles even when the whole ensemble seems to have lost its coherence.

The aim of this study is to characterize the microstructure and high temperature induced structural changes within fiber reinforced silicon carbide (SiCf/SiC) composites by means of non-destructive techniques. In order to understand their properties, the characterization of the microstructure of SiCf/SiC composites is the crucial issue. Porosity within composites is unavoidable with currently available manufacturing processes, and reduces significantly the life time and performance of the composites under harsh environments. Moreover, the internal pores, created in the manufacturing process cause the degradation most of the outstanding properties such as thermal conductivity, mechanical properties at high temperature, and radiation stability. Cold neutron tomography and diffusion structural diagnostic techniques were applied in the investigation of the microstructure of SiCf/SiC composites to gain complementary information. One of the main obstacles to using these composites in fusion technology and other applications are a change of the porous structure and a swelling at high temperatures and in a severe radiation environment. Cold neutron tomography enables visualization of the microstructure of the composite and consequently the pore distributions within the SiCf/SiC composite were observed with a suitable resolution. The diffusion structural diagnostic technique was used to characterize the thermal behavior of SiCf/SiC composites on heating up to 1300 °C.

The Kochen-Specker theorem theoretically shows evidence of the incompatibility of noncontextual hidden variable theories with quantum mechanics. Quantum contextuality is a more general concept than quantum non-locality which is quite well tested in experiments by using Bell inequalities. Within neutron interferometry we performed an experimental test of the Kochen-Specker theorem with an inequality, which identifies quantum contextuality, by using spin-path entanglement in a single neutron system. Here entanglement is achieved not between different particles, but between degrees of freedom, i.e., between spin and path degree of freedom. Appropriate combinations of the spin analysis and the position of the phase shifter allow an experimental verification of the violation of an inequality of the Kochen-Specker theorem. The observed value of (2.291 +/- 0.008), which is above the threshold of 1, clearly shows that quantum mechanical predictions cannot be reproduced by noncontextual hidden variable theories., Comment: 5 pages, 3 figures

Pilot study to compare the effect of inhaled nitric oxide (iNO) and aerosolized iloprost in preventing perioperative pulmonary hypertensive crises (PHTCs).Guidelines recommend the use of iNO to treat PHTCs, but treatment with iNO is not an ideal vasodilator. Aerosolized iloprost may be a possible alternative to iNO in this setting.Investigator-initiated, open-label, randomized clinical trial in 15 infants (age range 77-257 days) with left-to-right shunt (11 out of 15 with additional trisomy 21), and pulmonary hypertension (i.e. mean pulmonary artery pressure [PAP]25 mmHg) after weaning from cardiopulmonary bypass. Patients were randomized to treatment with iNO at 10 ppm or aerosolized iloprost at 0.5 µg/kg (every 2 h). The observation period was 72 h after weaning from cardiopulmonary bypass. The primary endpoint was the occurrence of PHTCs; the secondary endpoints were mean PAP, duration of mechanical ventilation, safety of administration, and in-hospital mortality.Seven patients received iNO and eight patients received iloprost. During the observation period, 13 of the 15 patients had at least one major or minor PHTC. There was no difference between the groups with regard to the frequency of PHTCs, mean PAP and duration of mechanical ventilation (p 0.05).In this pilot study, aerosolized iloprost had a favorable safety profile. Larger trials are needed to compare its efficacy to iNO for the treatment of perioperative pulmonary hypertension. However, neither treatment alone abolished the occurrence of PHTCs.

In 1974 perfect crystal interferometry has been developed and immediately afterwards the 4π-symmetry of spinor wave-functions has been verified. The new method opened a new access to the observation of intrinsic quantum phenomena. Spin-superposition, quantum state reconstruction and quantum beat effects are examples of such investigations. In this connection efforts have been made to separate and measure various dynamical and geometrical phases. Non-cyclic and non-adiabatic topological phases have been identified and their stability against various fluctuations and dissipative forces has been investigated by means of ultra-cold neutrons. An entanglement between different degrees of freedom of a single neutron system demonstrated the contextuality feature of quantum mechanics. In its continuation this yields to Kochen-Specker theorem like investigations providing a new basis for information processing and for the understanding of quantum physics in general. All investigations show the equivalence of various phase spaces and show how physical phenomena are correlated by quantum laws. Some curiosa occurred during the experiments and some epistemological aspects will be discussed as well.

Primary neutron sources are based on research reactors and spallation sources whose peak fluxes are limited to values below 1017 cm−2s−1[1,2]. In this paper we present a method which can complement and improve the performance of existing and upcoming dedicated neutron sources [3].

Non-local correlations between subsystems sufficiently separated in spacetime have been extensively discussed in the light of the Einstein, Podolsky and Rosen (EPR) paradox, together with Bell's inequality. Within quantum terminology, such a non-locality can be interpreted as a consequence of the entanglement of subsystems. A more general concept, i.e., quantum contextuality, compared to non-locality, can be introduced to describe other striking phenomena predicted by quantum theory. As examples of quantum contextuality, we report several neutron interferometer experiments: a violation of a Bell-like inequality, a Kochen–Specker-like phenomenon, a quantum state tomography. Entanglement is achieved not between the particles, but between the degrees of freedom of a single-particle. Furthermore, an experiment dealing with triple entanglement is presented.

Small-angle neutron scattering (SANS) and ultra-small-angle neutron scattering (USANS) measurements of the structure of two Australian bituminous coals (particle size of 1-0.5 mm) before, during, and after exposure to 155 bar of helium were made to identify any effects of pressure alone on the pore size distribution of coal and any irreversible effects upon exposure to high pressures of helium in the pore size range from 3 nm to 10 μm. No irreversible effects upon exposure were identified for any pore size. No effects of pressure on pore size distribution were observed, except for a small effect at a pore size of about 2 μm for one coal. This study provides a convenient baseline for SANS and USANS investigations on sorption of gases at elevated pressures on coals, by distinguishing between the effect of pressure alone on coal pore size distribution and against the effect of the gas to be investigated.

Neutron scattering is an important tool for the investigation of static and dynamic structures of matter. As it is an intensity limited technique, many attempts have been made to increase the effective beam intensity. High neutron intensities or, more precisely, high phase space densities of neutrons can be obtained at low energies only. Such ultra-cold neutrons can be trapped inside material and magnetic bottles. When neutrons of such densities become up-scattered, highly intense, monochromatic and pulsed beams can be produced, whose intensities can overcome limitations imposed by the classical neutron source strength. We report a recent experiment that demonstrated this alternative, to our knowledge, for the first time ever. Perspectives resulting from this development of highly intense neutron beam production will be discussed. A stationary ultra-cold neutron gas produced becomes transformed into a pulsed and monochromatic cold neutron beam.

The chemical preservation and structural reintegration of natural stones applied in historical buildings is carried out by the use of different stone strengtheners. As these agents contain hydrogen, they offer good properties for neutron imaging. The main interest in the restoration process is the development of a suitable stone consolidant. In cooperation with the St. Stephans Cathedral and the geologists at Vienna University of Technology, we are investigating the penetration depth and distribution of different stone consolidants. These studies are being carried out with different stone samples, mostly porous natural building stones, limestones and sandstones. The two strengtheners used in this study are ethyl silicate ester (Wacker OH100) and dissolved polymethylmetacrylate (PMMA, Paraloid B72). Neutron radiography and neutron tomography can be used successfully to visualize the distribution of consolidants both in two and three dimensions.

Neutrons are particularly useful to study the evolution of a genuine spin- 1 2 quantum system and its interaction with the environment. We report on the characteristics of a newly designed apparatus for storing ultra-cold neutrons (UCN) and manipulating their spin by means of a 3D Helmholtz-coil arrangement. In particular, using UCN requires homogeneous and stable magnetic fields across the storage volume in order to maintain a spin-superposition state for a sufficiently long time. Experimental results on the successful manipulation of the neutrons spin by means of Rabi oscillations and Ramsey interference fringes with a newly designed apparatus are presented. Coherence times exceeding 500 ms make the apparatus suitable for further measurements on (de-)coherence and geometric phases.

The curious dual nature of the neutron, sometimes a particle, sometimes a wave, is wonderfully manifested in the various non-local interference and quantum contextuality effects observed in neutron interferometry. Non-classical states may become useful for novel fundamental and solid state research. Here we discuss unavoidable quantum losses as they appear in neutron phase-echo and spin rotation experiments and we show how entanglement effects in a single particle system demonstrate quantum contextuality. In all cases of interactions, parasitic beams are produced which cannot be recombined completely with the original beam. This means that a complete reconstruction of the original state would, in principle, be impossible which causes a kind of intrinsic irreversibility. Even small interaction potentials can have huge effects when they are applied in quantum Zeno-like experiments. Recently, it has been shown that an entanglement between external and internal degrees of freedom exists even in single particle systems. This contextuality phenomenon also shows that a quantum system carries much more information than usually extracted. The path towards advanced neutron quantum optics will be discussed.

Interferometry with massive elementary particles combines particle and wave features in a direct way. In this respect, neutrons are proper tools for testing quantum mechanics because they are massive, they couple to electromagnetic fields due to their magnetic moment, and they are subject to all basic interactions, and they are sensitive to topological effects, as well. They play a pionieering role in the development of interferometry with even heavier objects, like atoms, molecules and clusters. Deterministic and stochastic partial absorption experiments can be described by Bell-type inequalities. Recent neutron interferometry experiments based on postselection methods renewed the discussion about quantum nonlocality and the quantum measuring process. It has been shown that interference phenomena can be revived even when the overall interference pattern has lost its contrast. This indicates persisting coupling in phase space even in cases of spatially separated Schrodinger cat-like situations. These states are extremely fragile and sensitive to any kind of fluctuations or other decoherence processes. More complete quantum experiments also show that a complete retrieval of quantum states behind an interaction region becomes impossible in principle. The transition from a quantum world to a classical one is still an open question and will be tackled by means of dedicated decoherence experiments. Recent measurements deal with quantum contextuality and quantum state reconstruction. The observed results agree with quantum mechanical laws and may stimulate further discussions about their interpretations.

Microfabricated silicon gratings provide unique test procedures for instruments in neutron scattering and the interpretation of experimental data. Ultra-Small Angle Neutron Scattering (USANS) is currently becoming an effective technique for the analysis of structures in the micrometer range. A series of one-dimensional silicon gratings was fabricated using a highly anisotropic ion etching technique (RIE) and measured at the USANS instrument S18 at ILL, Grenoble. The scattering patterns show up to 17 orders of diffraction, grating parameters derived from these data are in good agreement with the nominal values. Scattering length density correlation functions calculated from the USANS data are compared to Spin Echo SANS (SESANS) correlation functions measured at the Delft University of Technology, demonstrating the complementarity of the two scattering methods.

Ultra-Small-Angle Neutron Scattering (USANS) is currently becoming an effective technique for the analysis of structures in the micrometer range. The new Spin-Echo SANS (SESANS) method measures a signal in real space. In both cases microfabricated silicon gratings provide unique test procedures for the related devices and interpretations of the experimental data. A series of one-dimensional gratings was fabricated using a highly anisotropic ion etching technique (RIE) and measured at the USANS instrument S18 at ILL, Grenoble. Grating parameters derived from the experimental data are in agreement with the nominal values. Scattering length density correlation functions calculated from the USANS data are compared to SESANS correlation functions measured at the Delft University of Technology, demonstrating the reciprocity of the two scattering methods. Reconstruction techniques for one-dimensional scattering length density distributions are applied to the USANS data. The results are in good agreement with SEM micrographs of the samples.

The phase-object approximation for neutron scattering based on a one-dimensional dynamic forward scattering theory is discussed and used to calculate the differential cross section of an object. It is shown that this approximation is valid in ultra-small-angle neutron scattering (USANS) and spin-echo small-angle neutron scattering (SESANS) experiments on silicon gratings. In the weak scattering limit, the phase-object approximation reduces to the kinematic or first Born approximation. The spatial coherence function is used to describe instrumental resolution effects. Measurements on three different instruments are in good agreement with calculation results. In the experiment with a time-of-flight SESANS instrument, the effect ofPendellösungwith object size is observed.

Patients with glutaric aciduria type I are at risk for acute striatal injury precipitated by catabolic stress. Here, we report the successful interdisciplinary anesthetic and perioperative management of a child with glutaric aciduria type I undergoing cardiac surgery with extracorporeal circulation. Given the central focus on prevention of acute striatal injury, our anesthetic strategy emphasized avoiding a high protein load, high-dose inotropics, especially epinephrine (associated with impaired glucose utilization), deliberate hyperventilation, and other interventions associated with systemic inflammatory response.

Quantum mechanics with massive particles has developed into an important tool for fundamental and applied research since many previously proposed “Gedanken” experiments have now become feasible. Neutrons are massive particles which couple to gravitational, nuclear and electro-magnetic interactions and, furthermore, are sensitive to topological effects. Spatially widely separated coherent beams of neutrons can be produced by means of perfect crystal interferometers and these beams can be influenced individually. Spinor symmetry, spin superposition and quantum beat effect experiments have been performed and topological phases have also been observed. To achieve an interference pattern of high quality, the experimenter is, most of the time, fighting against various decoherencing effects. However, decoherence phenomena are fundamental features of quantum physics and deserve detailed investigations. In post-selection experiments it is, in many cases, possible to retrieve a substantial part of the lost coherence features. The latter are inherently connected to unavoidable losses which stem partly from the theory and partly from an imperfect environment. In existing experiments neither a completely coherent nor a completely incoherent situation can be achieved since decoherence sets in with the first interaction experienced by the quantum system.

The coaptation zone is the part of the two mitral valve leaflets that collide during the cardiac cycle. It is an important parameter for the valve’s function and closing capability, but difficult to assess. In this work, we present an automatic approach for leaflet segmentation from 4D ultrasound images, which incorporates steps for coaptation zone modelling and allows determining the coaptation zone from the resulting leaflet surface. The method segments the leaflets over the whole cardiac cycle given a previously segmented annulus model. To provide a meaningful analysis of the coaptation line assessment, the mean error between ground truth model and segmented model has been computed for each leaflet separately. For the anterior leaflet, we achieved a mean error of \(1.16 \pm 0.38\) mm and \(1.24 \pm 0.37\) mm for the posterior leaflet, respectively.

Non-local correlations between sufficiently separated subsystems have been extensively discussed. Such a non-locality can be interpreted as a consequence of the correlation between commuting observables. A more general concept, i.e., contextuality, compared to non-locality can be introduced to describe striking phenomena predicted by quantum theory. As the first example, we report a neutron interferometer experiment, where the spin and the path degrees of freedom are used to exhibit the clear violation of a Bell-like inequality. Other aspects of the quantum contextuality is presented, e.g., a flavor of Kochen–Specker-like contradiction in neutron optical experiments, in addition to the quantum state tomography of the Bell-states which are used in the experiments.

Neutron interferometry using monolithic perfect single crystals has become an important tool for fundamental, nuclear, and solid-state physics research. New features of quantum mechanics become measurable by means of neutron interferometry. Such features are quantum phases, which provide a more direct access to properties of wave functions and permit wave function reconstruction, and wave function engineering. Most recently, new experiments concerning off-diagonal and non-cyclic geometrical phases, confinement induced phases, and contextuality related experiments have been performed. These experiments show an intrinsic entanglement of different degrees of freedom of a single particle. Proper post-selection experiments yield to more quantum complete experiments and may help to make quantum mechanics less mystic. Unavoidable quantum losses may play an important role to explain the transition from the quantum to the classical world. All these investigations concern the heart of quantum mechanics and demonstrate the non-local feature of this theory.

The phase of a quantum state comprises information about the geometry of the state space. For example, in a magnetic field the spin state of a neutron traces out a particular path in its spherical shaped state space and the geometric phase acquired during this evolution reflects the curvature of this sphere. But the geometric phase is not only restricted to the spinor wave function, also the path of the neutron in an interferometer gives rise to a non trivial momentum state space and consequently to a geometric phase. Experimental results for a non-cyclic evolution are presented that are in agreement with theoretical predictions derived purely from geometrical considerations. By obeying a parallel transport condition dynamical contributions could largely be avoided and the measured phase is of geometric nature.