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Various types of magnetic nanoparticles have been developed for a range of medical applications and some have the potential to treat diseases. In this paper, a new method for controlling the position of these magnetic particles by changing the magnetic field surrounding them using three Halbach ringsis investigated with the aid of a simulation. The inner ring controls the direction, and the position of the two outer rings can keep the group of particles together. In the simulation, the magnetic field is calculated analytically for each time step and the movement of the particles is simulated by applying the corresponding forces. These result from the manipulable external magnetic field, the magnetic field between the particles, the Lennard-Jones potential to model attractive interactions between the particles and the drag. In the simulation, we show how the particles are manipulated using a Levenberg-Marquard algorithm and develop a closedloop control for the position of the grouped particles by manipulating the magnetic field inside the Halbach rings by changing the angular position of these rings.

This paper presents a simulation system (“patient model”) for intraoperative neuromonitoring (IONM) applied to mastoidectomy. IONM is an electrophysiological method for monitoring the integrity and localization of nerve tracts, which helps the surgeon to avoid injuries and damage to neural risk structures (e.g. facial nerve) during surgery. To use the IONM successfully, the surgeon needs appropriate training and experience. The presented simulation system provides training possibilities in a realistic, cost-efficient and reproducible way. In the simulation system, the position of the probe during training is determined by a magnetic tracking method. Depending on the distance to the virtual nerve, a synthetic electromyogram (EMG) signal is sent to a real neuromonitor. The trainee learns to interpret the output of the neuromonitor. The trainer can choose different training scenarios, such as localization of the nerve, milling or coagulating, using a web application.

Digitale Zwillinge werden in der Betriebsphase einer Maschine oder Anlage für verschiedene Fragestellungen angewendet, bspw. für die Zustandserkennung. Voraussetzung dafür ist, dass der Digitale Zwilling über Modelle des Anlagenverhaltens verfügt, die verschiedene Zustände, einschließlich von Fehlerzustände, adäquat beschreiben. Ein wesentlicher Aspekt dabei ist die Identifikation der Modellparameter. Dieser Beitrag dient der Analyse und Anpassung ausgewählter Optimierungsmethoden (gradientenbasierter Verfahren und ein Partikelschwarmoptimierer) am Beispiel von Modellen für Kompressoren und Turbinenanlagen. Dazu wird mit einem analytischen Ansatz ein Modell einer realen Kompressoranlage erstellt. Um die Qualität der Optimierungsergebnisse vergleichen zu können, wird eine Fehlermetrik eingeführt. Das Verhalten der Optimierer wird unter den folgenden realistischen Fehlerszenarien ermittelt: Fehler in den Modellparametern, Rauschen, initialer Abstand vom Optimum, fehlerhaft Messstellen (ohne und mit Detektion). Zur numerischen Bewertung der Identifizierbarkeit werden zwei Kriterien eingeführt.

Purpose: African-American men (AAM) have a greater risk of hypertension (HTN) than Caucasian men (CM). To reduce this risk, determining the differences in mechanisms involved in HTN and understanding the relationship between these mechanisms and factors affecting blood pressure (BP) in AAM and CM is necessary. One such mechanism is spontaneous baroreflex sensitivity (sBRS) and two factors are cardiorespiratory fitness (CRF) and arterial stiffness (AS). The aims of this study were to determine, firstly, whether there are differences in sBRS between young, normotensive AAM and CM, and secondly, to determine if CRF and AS are significant predictors of sBRS in young, normotensive AAM and CM. Methods: Twenty-three normotensive AAM and 36 CM were recruited from Southern Connecticut State University. Measures included anthropometric, sBRS (alpha-index), and CRF (maximal oxygen consumption [VO2max]), as well as AS (carotid-femoral pulse wave velocity [Cf-PWV]). Independent t-tests were used to determine differences between groups and multiple regression analysis was used to determine how much of the variation in sBRS was explained by CRF and AS. Results: The sBRS was significantly lower in AAM (10.3 ± 3.8 ms/mmHg) vs. CM (13.3 ± 5.7 ms/ mmHg), P = 0.03. CRF and AS were not significant predictors of sBRS in AAM (P = 0.25) and CM (P = 0.30). There was no relationship between, sBRS, CRF and AS; CRF was significantly reduced in AAM vs. CM (45.1 ± 6.3 vs. 52.1 ± 7.5 mL·kg−1·min−1, P ≤ 0.001). Conclusions: Young normotensive AAM demonstrated significantly lower sBRS vs. CM, irrespective of having fair CRF and normal BP. CRF and AS are not significant predictors of sBRS in young, normotensive AAM and CM. The attenuation in sBRS in AAM did not result in AAM having higher BP versus CM. This finding underscores the need for more detailed examination of the role of sBRS in the etiology of HTN in AAM.

Purpose: Aortic augmentation index (AIx) and cardiovagal tone (CVT) are indicators of cardiovascular health. Associations between these variables provide information about their roles in cardiovascular disease. However, evaluating these associations from a gender perspective and gaining an understanding of the relationship between cardiorespiratory fitness and AIx based on gender can provide additional information. Therefore, we examined the relationships between CVT, measured as the log transformed high-frequency power of R-R intervals from electrocardiogram measurements (lnHFR-R); cardiorespiratory fitness, measured as maximum oxygen consumption (VO2max); and AIx at a heart rate of 75 beats·min-1(AIx@75). We hypothesized that the relationships between CVT, cardiorespiratory fitness, and AIx@75 would differ based on gender. Methods: We examined the associations between lnHFR-R, VO2max, and AIx@75 in 41 women and 39 men. Power spectral density analysis of heart rate variability determined lnHFR-R, radial tonometry determined AIx@75 and the Bruce Treadmill Protocol determined VO2max. Results: In men, lnHFR-R positively correlated with and significantly predicted AIx@75 (P = 0.005) but not in women (P = 0.49). For every unit increase in lnHFR-R, there was a 4.6 unit increase in AIx@75 in men versus a 1.0 unit increase in women. There was a significant inverse relationship between VO2max and AIx@75, with VO2max being a significant predictor of AIx@75 in men (P = 0.01). For every unit increase in VO2max, there was a 0.60 unit decrease in AIx@75 in men versus a 0.2 unit decrease in women. Conclusions: The associations between CVT and AIx@75 and between cardiorespiratory fitness and AIx@75 differ by gender. CVT and cardiorespiratory fitness are significant predictors of AIx@75 in men but not in women.

The following article summarizes United States Patent Application No. US20180052155A1, titled ‘Assay Devices and Methods’ (filed 16 August 2016, published 22 February 2018). While lateral flow assays (LFAs) have revolutionized point-of-care diagnostics by enabling accurate, inexpensive, and rapid detection of biomarkers, they typically do not provide quantitative results. Hence, there is a significant need for quantitative assays at the point of care. This patent summary describes a novel method of chronometric biomarker quantitation via enzymatic degradation of a metastable gelatin-based biomatrix, principally suited for use in paper-based microfluidic devices (microPADs). This new quantitation mechanism was designed to meet the ASSURED criteria for point-of-care diagnostic devices laid forth by the World Health Organization and may ultimately provide increased access to healthcare, at a significantly reduced cost, around the world.

We introduce a comprehensive public dataset, NightOwls, for pedestrian detection at night. In comparison to daytime conditions, pedestrian detection at night is more challenging due to variable and low illumination, reflections, blur, and changing contrast. NightOwls consists of 279k frames in 40 sequences recorded at night across 3 countries by an industry-standard camera, including different seasons and weather conditions. All the frames are fully annotated and contain additional object attributes such as occlusion, pose and difficulty, as well as tracking information to identify the same object across multiple frames. A large number of background frames for evaluating the robustness of detectors is included, a validation set for local hyper-parameter tuning, as well as a testing set for central evaluation on a submission server is provided. As a baseline for pedestrian detection at night time, we compare the performance of ACF, Checkerboards, Faster R-CNN, RPN+BF, and SDS-RCNN. In particular, we demonstrate that state-of-the-art pedestrian detectors do not perform well at night, even when specifically trained on night data, and we show there is a clear gap in accuracy between day and night detections. We believe that the availability of a comprehensive night dataset may further advance the research of pedestrian detection, as well as object detection and tracking at night in general.

To investigate the frequency of pancreatic duct (PD) variants and their effect on pancreatic exocrine function in a population-based study using non-invasive secretin-stimulated magnetic resonance cholangiopancreatography (sMRCP).Nine hundred and ninety-five volunteers, 457 women and 538 men, aged 51.9 ± 13.4 years, underwent navigator-triggered, T2-weighted, 3D turbo spin echo MRCP on a 1.5 T system after 1 unit/kg secretin administration. Two readers evaluated images for PD variants. Pancreatic exocrine function and morphological signs of chronic pancreatitis such as abnormalities of the main PD, side branch dilatation, and pancreatic cysts were evaluated and related to PD variants using a Kruskal-Wallis test and post hoc analysis.Of all sMRCP, 93.2% were of diagnostic quality. Interobserver reliability for detection of PD variants was found to be kappa 0.752 (95 %CI, 0.733 - 0.771). Normal PD variants were observed in 90.4% (n = 838/927). Variants of pancreas divisum was identified in 9.6% (n = 89/927). Abnormalities of the main PD, side branch dilatation, and pancreatic cysts were observed in 2.4%, 16.6%, and 27.7%, respectively, and were not significantly different between pancreas divisum and non-divisum group (P = 0.122; P = 0.152; P = 0.741). There was no association between PD variants and pancreatic exocrine function (P = 0.367).PD variants including pancreas divisum are not associated with morphological signs of chronic pancreatitis or restriction of pancreatic exocrine function.MRCP allows the evaluation of pancreatic duct variants and morphological change. Pancreatic duct variants are not associated with morphological signs of chronic pancreatitis. Pancreas divisum is not accompanied by restriction of pancreatic exocrine function. Pancreatic duct variants including pancreas divisum are limited in their clinical relevance.

To investigate three-echo T2*-corrected Dixon magnetic resonance imaging (MRI) for noninvasively estimating hepatic fat content (HFC) compared with biopsy.One hundred patients (50 men, 50 women; mean age, 57.7±14.2 years) underwent clinically indicated liver core biopsy (102 valid tissue samples) and liver MRI 24 to 72 hours later. MRI was performed at 1.5T (Magnetom Avanto, Siemens Healthcare, Erlangen, Germany) using Dixon imaging with T2* correction (work in progress, WIP-432.rev.1, Siemens Healthcare). An ultrafast breath-hold three-echo 3D-gradient echo sequence with TR/TE1/TE2/TE3 of 11/2.4/4.8/9.6 milliseconds, and online calculation of T2*-corrected water images (signal intensities of water [SIW]), fat images (SIF), and fat content map (SIFAT=10×SIF/(SIW+SIF)) was used. SIs of the calculated fat content map (SIFAT) were verified using the histologically quantified HFC (HFC(path)). Spearman correlation for HFC(path) and SIFAT was calculated. Stage of fibrosis, hepatic iron content, and patterns of liver fat (macrovesicular, microvesicular, mixed) and their influence on predicting HFC by MRI were determined.Correlation between SIFAT and HFC(path) was rspearman=0.89. Agreement between HFC predicted by MRI and HFC(path) calculated by nonlinear saturation-growth regression was rspearman=0.89. Kruskal-Wallis analysis revealed no significant difference for SIFAT across fibrosis grades (P=0.90) and liver iron content (P=0.76). Regarding the cellular architecture of liver fat, the microvesicular pattern showed lower mean ranks in SI than macrovesicular and mixed patterns (P=0.01).T2*-corrected Dixon MRI is a noninvasive tool for estimating HFC, showing excellent correlation with liver biopsy without being limited by liver iron content and fibrosis/cirrhosis.

Occupational segregation by race and gender, though less common now than in the past, continues to be the norm rather than the exception in the sport industry. The purpose of this study was twofold. First, occupational segregation on the baseball playing field, often referred to as stacking, was discussed in light of human capital and social closure theories. Second, an attempt was made to replicate and extend a multivariate analysis of stacking by Margolis and Piliavin (1999) that challenges the dominant social science paradigm for explaining stacking. The present study uses more recent data than the Margolis and Piliavin study, as well as multinomial logistic regression analysis. The results reveal that stacking persists in Major League Baseball. They also reveal that the effect of race/ethnicity on assignments to playing positions is reduced when one controls for skills and physical characteristics such as speed and power hitting. The implications of this finding for sport management are examined.

Jahrlich kommt es weltweit im Strasenverkehr zu rund 1,2 Millionen todlichen Unfallen. Allein in Europa ereignen sich 1,3 Millionen Unfalle, hierbei werden mehr als 40 000 Menschen getotet. Die Kosten dieser Verkehrsunfalle werden mit 160 Milliarden Euro beziffert. Dies entspricht rund 2 % des Bruttosozialprodukts der Europaischen Union. Mehr als ein Drittel aller todlichen Unfalle wird durch einen Spurwechsel oder ein unbeabsichtigtes Verlassen des Fahrstreifens ausgelost. Daraus lasst sich ableiten, dass durch ein Spurhalte-Assistenzsystem, insbesondere einer Warnung vor ungewolltem Verlassen des Fahrstreifens, eine Reihe von Unfallen verhindert oder zumindest in ihrer Schwere gemindert werden konnten. Spurhalte-Assistenzsysteme, wie sie in diesem Kapitel beschrieben werden, sind Fahrerassistenzsysteme, welche die Fahrzeugposition relativ zur Fahrstreifenmitte bestimmen und den Fahrer, sollte er unbeabsichtigt den Fahrstreifen verlassen, warnen oder das Fahrzeug durch einen automatischen Lenkeingriff wieder in den Fahrstreifen zuruckbewegen konnen.

Background: Cardiovascular disease is a primary cause of death worldwide. Low parasympathetic nervous activity (PNA) is associated with negative cardiovascular health (CVH) [1]. Central augmentation pressure (CAP), aortic pulse pressure (APP) and augmentation index (Alx) are all strong indicators of CVH. Heart rate variability (HRV) and recovery heart rate (RHR) are both indices of PNA but they do not correlate [2]. Since these indices do not correlation we hypothesized that there would be a difference in their relationship with CVH as determined by CAP, APP and Alx75. Aim: To determine if there is a difference in the relationships between HRV, RHR and CAP, APP and Alx inmen. Methods: Seventeen healthy college aged men were examined for HRV via power spectral density analysis. Recovery heart rate was examined at minute one (RHR1) and two (RHR 2)) following a VO2max test. Pulse wave analysis via applanation tonometry and a generalized transfer function was used to determine CAP, APP and Alx. Results: There was a significant correlation between HRV and CAP (r = 0.61, P = 0.01) and Alx (r = 0.51, P = 0.05). No correlation was observed between RHR 1, RHR 2 and CAP, Alx and APP. Central augmentation pressure was significantly correlated with APP (r = 0.67, P= 0.01) and Alx r = 0.64, P= 0.01). Conclusions: Findings suggest a difference in the relationship between HRV, RHR and CVH. Here HRV was positively correlated with indices of CVH, while RHR did not correlate with these indices. Indicating that HRV seem to be more indicative of CVH versus RHR.

To return our coastal streams and rivers to a natural, healthy and functioning state requires approaching restoration on a watershed scale. Because everything that goes on within the boundaries of its drainage basin can affect the stream, restoration requires a comprehensive and coordinated approach to stream health. To be effective, restoration must address the underlying causes of degradation, not merely the symptoms. As a result, restoring watershed health often requires improving the land management practices that may have contributed to increased sedimentation or nitrate pollution, degraded habitat, or greater flood damage. Unfortunately, we've created a number of institutional barriers to working at a watershed scale. Political jurisdictions rarely correspond to watersheds. The major environmental issues in a watershed—fish habitat, water quality, land use, water diversions, flood control, storm water management—are usually the responsibility of separate local, state or federal agencies, whose programs and responsibilities seldom mesh with one another. The laws that created those programs rarely recognize that watershed issues are connected and should be managed together. Even the science is often fragmented by a continuing trend to compartmentalize disciplines, emphasize analysis rather than synthesis, and ignore the social and economic implications of watershed issues.

643 Background: Many reports have shown the prognostic value of HER-2 measured in tumor tissue or in blood. In 2009, Finn et.al. showed that in a study of 579 MBC patients whose serum HER-2 levels (sHER-2) were constantly below normal had a longer PFS than patients with a sHER-2 level constantly above normal. Patients who converted from above normal to less than normal during therapy had a longer PFS than the opposite change. Methods: We performed a Bayesian meta-analysis of 12 studies where all sHER-2 levels were measured using an FDA cleared sHER-2 test with a standard cutoff of 15ng/ml. We chose a Bayesian approach because a “meta-analysis” is a natural extension of the Bayesian view that current knowledge is the result of prior knowledge modified by the data. After an in depth literature search, we selected 12 publications based on the following criteria. Baseline levels were available from either early stage or late stage patients who had at least a 2 year disease free or progression free survival as indicated by a Kaplan-Meier (K-M) curve. Results: The analysis included 4030 BC patients of which 1106 patients had baseline levels < 15ng/ml and 2924 patients had baseline values >15ng/ml. From the K-M curves, we estimated the number of recurrences up to 24 months in each group and prepared a 2x2 table for each study. We determined the odds ratio (OR) for the 12 studies which ranged from 0.57 to 74. A posterior distribution for the aggregated 12 studies can be represented by a Dirichlet distribution. 10,000 estimates of the aggregated OR indicated that there is a 95% credibility that the odds of a woman with baseline sHER-2 >15ng/ml recurring at or before two years is between 3.39 and 4.57 times higher than the odds of a woman whose baseline sHER-2 was < 15ng/ml recurring at or before two years. Conclusions: This meta-analysis agrees with previous studies that serum HER-2 levels > 15ng/ml can be a strong prognostic indicator for women with Breast Cancer and that managing therapy regimens to maximize the decrease in serum HER-2 levels could be important target in treating patients.

Data from a national survey of college basketball players are analyzed to identify conditions that cause student athlete role conflict and the coping mechanisms used to make this conflict more manageable. NCAA division was found to be strongly related to role conflict regardless of the measure used. Gender was also found to have an impact. Role conflict was also related to scholarship status, the number of hours athletes perceive they must devote to basketball, and whether they believe their coaches make unreasonable demands on their time and energy. It was also found that athletes who ranked low in their high school graduating class and had sought help from an academic counselor were more likely than others to deal with role conflict by taking various academic shortcuts. One final conclusion is that the vast majority of college athletes, with the exception of Division I males, have little problem reconciling their roles as athletes and students.

Bei der Umsetzung von Silizium-Tetrachlorid mit Wasserstoff in einer heis-kalten Rohre entsteht in der Hauptsache ein Siliziumchlorid der Formel Si10Cl20H2. Die Verbindung stellt ein farbloses, auserordentlich viskoses Ol dar. Molekulargewichtsbestimmung, Analyse und Ermittlung der bei der durchgreifenden Hydrolyse entwickelten Wasserstoffmenge gestatten die Feststellung, das die Verbindung aus einer Kette von 10 Silizium-Atomen aufgebaut ist.

This study examined the social origins and career mobility of college football players who graduated from Notre Dame between 1946 and 1965. It was found that Notre Dame football players came from much lower socioeconomic backgrounds than regular Notre Dame students. In terms of social mobility, both ballplayers and regular students from lower socioeconomic backgrounds have moved well beyond their social origins. Only in educational attainment do the two groups differ significantly. Among ballplayers, first teamers experienced greater income mobility than second teamers and reserves. First team ballplayers were also found to be over-represented as top ranking executives in their companies.