Search

We studied the impact of soft ferromagnetic permalloy (Py) on the shielding currents in a strong-pinning superconductor—YBa _2 Cu _3 O _7− _δ with Ba _2 Y(Nb/Ta)O _6 nano-precipitates—by means of scanning transmission x-ray microscopy. Typically and in particular when in the thin film limit, superconductor/ferromagnet (SC/FM) bilayers exhibit isotropic properties of the flux line ensemble at all temperatures. However, in elements with small aspect ratio a significant anisotropy in flux penetration is observed. We explain this effect by local in-plane fields arising from anisotropic magnetic stray fields originated by the ferromagnet. This leads to direction-dependent motion of magnetic vortices inside the SC/FM bilayer. Our results demonstrate that small variations of the magnetic properties can have huge impact on the superconductor.

Magnetic imaging of superconductors typically requires a soft-magnetic material placed on top of the superconductor to probe local magnetic fields. For reasonable results the influence of the magnet onto the superconductor has to be small. Thin YBCO films with soft-magnetic coatings are investigated using SQUID magnetometry. Detailed measurements of the magnetic moment as a function of temperature, magnetic field and time have been performed for different heterostructures. It is found that the modification of the superconducting transport in these heterostructures strongly depends on the magnetic and structural properties of the soft-magnetic material. This effect is especially pronounced for an inhomogeneous coating consisting of ferromagnetic nanoparticles. [ABSTRACT FROM AUTHOR]

Additive manufacturing offers a wide range of possibilities for the design and optimization of lightweight and application-tailored structures. The great design freedom of the Laser Powder Bed Fusion (LPBF) manufacturing process enables new design and production concepts for heat pipes and their internal wick structures, using various metallic materials. This allows an increase in heat pipe performance and a direct integration into complex load-bearing structures. An important influencing factor on the heat pipe performance is the internal wick structures. The complex and filigree geometry of such structures is challenging in regards to providing high manufacturing quality at a small scale and varying orientations during the printing process. In this work, new wick concepts have been developed, where the design was either determined by the geometrical parameters, the process parameters, or their combination. The wick samples were additively manufactured with LPBF technology using the lightweight aluminum alloy Scalmalloy ® . The influence of the process parameters, geometrical design, and printing direction was investigated by optical microscopy, and the characteristic wick performance parameters were determined by porosimetry and rate-of-rise measurements. They showed promising results for various novel wick concepts and indicated that additive manufacturing could be a powerful manufacturing method to further increase the performance and flexibility of heat pipes.

Background: There is still a lack of a clinical test to reliably identify patients with Parkinson's disease (PD) being at risk for aspiration., Methods: In this prospective, controlled, cross-sectional study, we assessed if swallowing speed for water is a useful clinical test to predict aspiration proven by flexible endoscopic evaluation of swallowing (FEES). Due to this, we measured the swallowing speed for 90 mL water in 115 consecutive and unselected PD outpatients of all clinical stages and 32 healthy controls., Key Results: Average swallowing speed was lower in patients compared with controls (6.5 ± 3.9 mL/s vs 8.5 ± 3.2 mL/s; P < .01). The disease-independent widely used threshold of <10 mL/s showed insufficient sensitivity of 88% and specificity of 19% with high false-positive rates of 63% for patients and 69% for controls. Receiver operating characteristic (ROC) analysis was carried out to define a suitable cutoff value for detection of aspiration of water (area under the curve 0.72, P < .001) in PD patients. The optimized cutoff value was 5.5 mL/s with a sensitivity of 69% and a specificity of 64%., Conclusion and Inferences: Measuring swallowing speed is prone to methodological errors and not suitable as a screening instrument to predict aspiration in PD patients., (© 2019 John Wiley & Sons Ltd.)

Background: This study evaluates the prevalence, characteristics, and predictors of the difficulty of swallowing medication in Parkinson's disease (PD)., Methods: In this prospective controlled, cross-sectional cohort study, the ability to swallow four different placebos was assessed using flexible endoscopic evaluation of swallowing (FEES) in 118 PD patients and 32 controls. The association between a patient's swallowing ability for each pill and water, patient characteristics and dopaminergic response was examined. The value of two swallowing screening questions was also evaluated., Results: Substantially impaired ability to swallow pills was found in 28% (n = 33/118) of patients and 16% (n = 5/32) of controls (p = 0.18). Higher disease severity was associated with more problems with swallowing pills (p = 0.03), but PD patients with short disease duration (<2 years), low H&Y stage (1-2), and younger age (<70 years) were also affected (each at least in 20%). Capsules were the easiest to swallow while oval tablets were the most difficult (p < 0.01, r = 0.21). Most patients (73%, n = 24/33) presented with swallowing problems only for a single formulation. Aspiration of water was found in 48% of patients, suggesting a possible increased risk of aspiration when taking dissolved tablets. Standardized questionnaires showed insufficient sensitivity (52% both) but fairly good specificity (69-74%) for dysphagia of pills. Dysphagia for medication was not associated with a lack of dopaminergic response., Conclusions: Dysphagia of medication occurs preferentially in advanced disease stages. An assessment of pill swallowing using FEES is suggested at least in patients reporting swallowing problems. Capsules might be preferentially used when dysphagia is suspected., (Copyright © 2019. Published by Elsevier Ltd.)

Background: Dysphagia is common in Parkinson's disease (PD) and leads to pneumonia, malnutrition, and reduced quality of life. For detecting dysphagia-exposed PD patients, the Munich dysphagia test-Parkinson's disease (MDT-PD) is a patient self-reported tool that has been developed specifically for PD patients. The MDT-PD is available in both German and English. This study aimed to ascertain whether the MDT-PD can detect aspiration in PD patients and, therefore, serve as a suitable screening tool., Methods: In a controlled, cross-sectional, observational study, a total of 119 PD outpatients were examined clinically and were evaluated by the MDT-PD and the one swallowing question (NMS-3) from the nonmotor symptom questionnaire for Parkinson's disease (NMSQuest). The results of the MDT-PD and the NMS-3 were compared to the penetration-aspiration scale (PAS) rating defined by flexible endoscopic evaluation of swallowing (FEES)., Key Results: Half of the patients with aspiration as determined using FEES were not detected by the MDT-PD and NMS-3 self-reported tools. The proportion of false positive patients was high with both tools. The sensitivity of the MDT-PD to detect patients who are at risk for aspiration is insufficient (0.37) and not superior to applying the dysphagia screening question from the NMSQuest (0.5)., Conclusion: This study reveals that the MDT-PD is not suitable for detecting aspiration in PD patients and, therefore, cannot be considered as a screening tool for aspiration. However, at present, there is no alternative validated screening tool that can reliably detect aspiration in PD patients. A readjustment of the MDT-PD is urgently needed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Do the current swallow-specific subquestions of neurological diagnostic tools reflect the objective swallowing function in Parkinson's disease (PD) patients or are clinical factors superior to predict critical aspiration?, Methods: In a cross-sectional, observational study a total of 119 Parkinson outpatients were examined clinically and by flexible-endoscopic evaluation of swallowing (FEES). Self-reported dysphagia by subquestions of the MDS-UPDRS and NMS questionnaire and history of subjective aspiration signs were collected., Key Results: Nearly, all PD patients showed deglutition abnormalities in FEES (113/119) while only 12%-27% of them reported swallowing problems in the swallow-specific subquestions of neurological standard diagnostic tools (MDS-UPDRS and NMS-Quest), and the answers were heterogeneous and poorly reproducible. With a sensitivity of up to a maximum of 50%, self-reported dysphagia is therefore no reliable tool for identifying dysphagia in PD. While most clinical parameters were linked to dysphagia to some extent, logistic regression analysis revealed high age (Odds Ratio (OR) 1.1 in years, 95% CI 1.03-1.18, P < 0.01), gender (OR 0.3 for females, 95% CI 0.08-0.97, P = 0.04), and affirmed subjective aspiration signs (OR 8.6, 95% CI 3.05-26.52, P < 0.001) as the most significant predictors for critical dysphagia., Conclusions and Inferences: Self-perception of swallowing is no reliable tool for identifying dysphagia and questionnaires are insufficient for detecting previous aspiration. Consequent and specific asking for previous subjective aspiration signs is the single most important measure for identifying PD patients at risk for critical aspiration., (© 2018 John Wiley & Sons Ltd.)

Background: Dysphagia is frequent and clinically highly relevant in Parkinson's disease (PD). For a rational dysphagia screening predictors are required. Previous investigations suggested that drooling correlates with dysphagia and may serve as its early sign. The aim of this study was to clarify the interrelationship of drooling and dysphagia., Methods: In a controlled, cross-sectional, observational study, a total of 119 Parkinson outpatients and 32 controls were examined clinically and by flexible-endoscopic evaluation of swallowing (FEES). Drooling, dysphagia including retained pharyngeal secretions, and cognitive function were assessed by established evaluation scales., Key Results: Fifty percent of all PD patients but only 9% of controls had drooling (P < .001). Drooling and dysphagia were related in PD (P = .027) but the data do not support to view drooling as a hallmark symptom for critical dysphagia. Thirty-nine percent of the patients with critical aspiration had no drooling. In contrast, 41% of the patients with severe drooling had no clinically relevant dysphagia in FEES. The oral, but not the pharyngeal secretion management was impaired in PD patients and there was no clear association between drooling and pharyngeal secretion accumulation. Cognitive impaired patients had significantly more drooling (P = .005)., Conclusions & Inferences: Although frequent in PD, drooling and dysphagia are only weakly related and drooling cannot be viewed as an early sign of dysphagia. Our data further suggest that the underlying cause of drooling is located in the voluntary oral phase, which is negatively influenced by cognitive deficits., (© 2017 John Wiley & Sons Ltd.)

To assess the prevalence of dysphagia and its typical findings in unselected "real-world" Parkinson patients using an objective gold-standard method. This was a prospective, controlled, cross-sectional study conducted in 119 consecutive Parkinson patients of all stages independent of subjective dysphagia. Patients and 32 controls were clinically and endoscopically examined by flexible endoscopic evaluation of swallowing (FEES) to evaluate the deglutition with regard to three consistencies (water, biscuit, and bread). Typical findings of dysphagia like penetration and aspiration, residues, and leakage were assessed. Dysphagia was common in Parkinson patients and occurred in all, even early, disease stages. Only 5% (6/119) of patients showed a completely unremarkable deglutition. Aspiration was seen in 25% (30/119) of patients and always related to water. Residues occurred in 93% (111/119), most commonly for bread. Leakage was much less frequent and was found in only 3-18%, depending on consistency. In a significant fraction of patients, objective dysphagia was not subjectively perceived. A total of 16% of asymptomatic patients suffered from critical aspiration. Significant swallowing deficiencies already occurred in early disease. Aspiration was found in 4 of 20 (20%) patients with disease duration of less than 2 years. Seven of 57 patients (12%) with Hoehn and Yahr stage 2 suffered from severe aspiration. Given the high frequency of critical aspiration in Parkinson disease, these patients should be evaluated early for dysphagia to avoid complications and recommend an adequate therapy. FEES is a simple, cost efficient, minimally invasive method that is ideally suited for this purpose.

Diagnosis-Related Group (DRG) is a classification system, which groups patients according to their diagnosis and resource consumption. Common hand surgical diagnoses and procedures were processed using national DRG-groupers of six European countries. The upper thresholds of length of stay (LoS) are indicated for every country with the exception of Spain. The mean value in the series was 9.9 days for Germany, 4.5 days for Austria, 10.7 days for Italy, 9.7 days for Sweden and 9.4 days for the United Kingdom (UK). Germany and Austria also have lower thresholds of LoS and the average LoS.Multiple finger replantation presented the highest single case reimbursement in Germany, Austria and the UK (13,825 €, 10,576 € and 9,198 €). Scaphoid non-union had the highest single case reimbursement in Italy (2,676 €), flap coverage of wounds in Spain (5,506 €) and trapeziometacarpal arthritis in Sweden (5,350 €). The mean values for single case reimbursement were as follows: Germany 3,211 €, Austria 2,821 €, Italy 1,947 €, Spain 3,594 €, Sweden 2,403 € and the UK 3,253 €. Ten out of 19 cases showed the highest reimbursement in Spain, followed by the UK (5 cases), Sweden (2 cases), Germany and Austria (1 case each). Applying the case numbers of our clinic to the reimbursement system of each country, total proceeds would be 2.25 million € in Spain, 1.79 million € in Germany as well as the UK, 1.75 million € in Austria, 1.63 million € in Sweden and 1.22 million € in Italy. The consequences of international differences in efficiency and reimbursement are hard to assess as they are influenced by multiple factors that are seldom purely market-driven. However, the consideration of international data for benchmarking and refinement of national compensation systems should be a useful instrument.

Agenesis of the corpus callosum (ACC) is among the most frequent human brain malformations with an incidence of 0.5-70 in 10,000. It is a heterogeneous condition, for which several different genetic causes are known, for example, ACC as part of monogenic syndromes or complex chromosomal rearrangements. We systematically evaluated the data of 172 patients with documented corpus callosum abnormalities in the records, and 23 patients with chromosomal rearrangements known to be associated with corpus callosum changes. All available neuroimaging data, including CT and MRI, were re-evaluated following a standardized protocol. Whenever feasible chromosome and subtelomere analyses as well as molecular genetic testing were performed in patients with disorders of the corpus callosum in order to identify a genetic diagnosis. Our results showed that 41 patients with complete absence (agenesis of the corpus callosum-ACC) or partial absence (dysgenesis of the corpus callosum-DCC) were identified. Out of these 28 had ACC, 13 had DCC. In 11 of the 28 patients with ACC, the following diagnoses could be established: Mowat-Wilson syndrome (n = 2), Walker-Warburg syndrome (n = 1), oro-facial-digital syndrome type 1 (n = 1), and chromosomal rearrangements (n = 7), including a patient with an apparently balanced reciprocal translocation, which led to the disruption and a predicted loss of function in the FOXG1B gene. The cause of the ACC in 17 patients remained unclear. In 2 of the 13 patients with DCC, unbalanced chromosomal rearrangements could be detected (n = 2), while the cause of DCC in 11 patients remained unclear. In our series of cases a variety of genetic causes of disorders of the corpus callosum were identified with cytogenetic anomalies representing the most common underlying etiology., (Copyright 2008 Wiley-Liss, Inc.)