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Spatial orientation is based on a complex cortical network with input from multiple sensory systems. It is affected by training, sex and age as well as cultural and psychological factors, resulting in different individual skill levels in healthy subjects. Various neurological disorders can lead to different patterns or specific deficits of spatial orientation and navigation. Accordingly, numerous tests have been proposed to assess these abilities. Here, we compare the results of (1) a validated questionnaire-based self-estimate of orientation/navigation ability (Santa Barbara Sense of Direction Scale, SBSODS) and (2) a validated pen-and-paper two-dimensional perspective test (Perspective Taking Spatial Orientation Test, SOT) with (3) a newly developed test of finger-arm pointing performance in a 3D real-world (3D-RWPT) paradigm using a recently established pointing device. A heterogeneous group of 121 participants (mean age 56.5 ± 17.7 years, 52 females), including 16 healthy volunteers and 105 patients with different vestibular, ocular motor and degenerative brain disorders, was included in this study. A high correlation was found between 2D perspective task and 3D pointing along the horizontal (azimuth) but not along the vertical (polar) plane. Self-estimated navigation ability (SBSODS) could not reliably predict actual performance in either 2D- or 3D-tests. Clinical assessment of spatial orientation and memory should therefore include measurements of actual performance, based on a 2D pen-and-paper test or a 3D pointing task, rather than memory-based questionnaires, since solely relying on the patient’s history of self-estimated navigation ability results in misjudgments. The 3D finger-arm pointing test (3D-RWPT) reveals additional information on vertical (polar) spatial performance which goes undetected in conventional 2D pen-and-paper tests. Diseases or age-specific changes of spatial orientation in the vertical plane should not be clinically neglected. The major aim of this pilot study was to compare the practicability and capability of the three tests but not yet to prove their use for differential diagnosis. The next step will be to establish a suitable clinical bedside test for spatial memory and orientation.

Deficits in spatial memory, orientation, and navigation are often early or neglected signs of degenerative and vestibular neurological disorders. A simple and reliable bedside test of these functions would be extremely relevant for diagnostic routine. Pointing at targets in the 3D environment is a basic well-trained common sensorimotor ability that provides a suitable measure. We here describe a smartphone-based pointing device using the built-in inertial sensors for analysis of pointing performance in azimuth and polar spatial coordinates. Interpretation of the vectors measured in this way is not trivial, since the individuals tested may use at least two different strategies: first, they may perform the task in an egocentric eye-based reference system by aligning the fingertip with the target retinotopically or second, by aligning the stretched arm and the index finger with the visual line of sight in allocentric world-based coordinates similar to using a rifle. The two strategies result in considerable differences of target coordinates. A pilot test with a further developed design of the device and an app for a standardized bedside utilization in five healthy volunteers revealed an overall mean deviation of less than 5° between the measured and the true coordinates. Future investigations of neurological patients comparing their performance before and after changes in body position (chair rotation) may allow differentiation of distinct orientational deficits in peripheral (vestibulopathy) or central (hippocampal or cortical) disorders.

Background Objective and volumetric quantification is a necessary step in the assessment and comparison of endolymphatic hydrops (ELH) results. Here, we introduce a novel tool for automatic volumetric segmentation of the endolymphatic space (ELS) for ELH detection in delayed intravenous gadolinium-enhanced magnetic resonance imaging of inner ear (iMRI) data. Methods The core component is a novel algorithm based on Volumetric Local Thresholding (VOLT). The study included three different data sets: a real-world data set (D1) to develop the novel ELH detection algorithm and two validating data sets, one artificial (D2) and one entirely unseen prospective real-world data set (D3). D1 included 210 inner ears of 105 patients (50 male; mean age 50.4 ± 17.1 years), and D3 included 20 inner ears of 10 patients (5 male; mean age 46.8 ± 14.4 years) with episodic vertigo attacks of different etiology. D1 and D3 did not differ significantly concerning age, gender, the grade of ELH, or data quality. As an artificial data set, D2 provided a known ground truth and consisted of an 8-bit cuboid volume using the same voxel-size and grid as real-world data with different sized cylindrical and cuboid-shaped cutouts (signal) whose grayscale values matched the real-world data set D1 (mean 68.7 ± 7.8; range 48.9–92.8). The evaluation included segmentation accuracy using the Sørensen-Dice overlap coefficient and segmentation precision by comparing the volume of the ELS. Results VOLT resulted in a high level of performance and accuracy in comparison with the respective gold standard. In the case of the artificial data set, VOLT outperformed the gold standard in higher noise levels. Data processing steps are fully automated and run without further user input in less than 60 s. ELS volume measured by automatic segmentation correlated significantly with the clinical grading of the ELS (p Conclusion VOLT enables an open-source reproducible, reliable, and automatic volumetric quantification of the inner ears’ fluid space using MR volumetric assessment of endolymphatic hydrops. This tool constitutes an important step towards comparable and systematic big data analyses of the ELS in patients with the frequent syndrome of episodic vertigo attacks. A generic version of our three-dimensional thresholding algorithm has been made available to the scientific community via GitHub as an ImageJ-plugin.

Strong static magnetic fields, as used in magnetic resonance imaging (MRI), stimulate the vestibular inner ear leading to a state of imbalance within the vestibular system that causes nystagmus. This magnetic vestibular stimulation (MVS) also modulates fluctuations of resting-state functional MRI (RS-fMRI) networks. MVS can be explained by a Lorentz force model, indicating that MVS is the result of the interaction of the static magnetic field strength and direction (called “B0 magnetic field” in MRI) with the inner ear’s continuous endolymphatic ionic current. However, the high variability between subjects receiving MVS (measured as nystagmus slow-phase velocity and RS-fMRI amplitude modulations) despite matching head position, remains to be explained. Furthermore, within the imaging community, an “easy-to-acquire-and-use” proxy accounting for modulatory MVS effects in RS-fMRI fluctuations is needed. The present study uses MRI data of 60 healthy volunteers to examine the relationship between RS-fMRI fluctuations and the individual orientation of inner-ear anatomy within the static magnetic field of the MRI. The individual inner-ear anatomy and orientation were assessed via high-resolution anatomical CISS images and related to fluctuations of RS-fMRI networks previously associated with MVS. More specifically, we used a subject-specific proxy for MVS (pMVS) that corresponds to the orientation of the individual inner-ear anatomy within the static magnetic field direction (also called “z-direction” in MR imaging). We found that pMVS explained a considerable fraction of the total variance in RS-fMRI fluctuations (for instance, from 11% in the right cerebellum up to 36% in the cerebellar vermis). In addition to pMVS, we examined the angle of Reid’s plane, as determined from anatomical imaging as an alternative and found that this angle (with the same sinus transformation as for pMVS) explained considerably less variance, e.g., from 2 to 16%. In our opinion, an excess variability due to MVS should generally be addressed in fMRI research analogous to nuisance regression for movement, pulsation, and respiration effects. We suggest using the pMVS parameter to deal with modulations of RS-fMRI fluctuations due to MVS. MVS-induced variance can easily be accounted by using high-resolution anatomical imaging of the inner ear and including the proposed pMVS parameter in fMRI group-level analysis.

Intravenous contrast agent-enhanced magnetic resonance imaging of the endolymphatic space (ELS) of the inner ear permits direct, in-vivo, non-invasive visualization of labyrinthine structures and thus verification of endolymphatic hydrops (ELH). However, current volumetric assessment approaches lack normalization. The aim of this study was to develop a probabilistic atlas of the inner ear's bony labyrinth as a first step towards an automated and reproducible volume-based quantification of the ELS. The study included three different datasets: a source dataset (D1) to build the probabilistic atlas and two testing sets (D2, D3). D1 included 24 right-handed patients (12 females; mean age 51.5 ± 3.9 years) and D2 5 patients (3 female; mean age 48.8 ± 5.01 years) with vestibular migraine without ELH or any measurable vestibular deficits. D3 consisted of five patients (one female; mean age 46 ± 5.2 years) suffering from unilateral Menière's disease and ELH. Data processing comprised three steps: preprocessing using an affine and deformable fusion registration pipeline, computation of an atlas for the left and right inner ear using a label-assisted approach, and validation of the atlas based on localizing and segmenting previously unseen ears. The three-dimensional probabilistic atlas of the inner ear's bony labyrinth consisted of the internal acoustic meatus and inner ears (including cochlea, otoliths, and semicircular canals) for both sides separately. The analyses showed a high level of agreement between the atlas-based segmentation and the manual gold standard with an overlap of 89% for the right ear and 86% for the left ear (measured by dice scores). This probabilistic in vivo atlas of the human inner ear's bony labyrinth and thus of the inner ear's total fluid space for both ears represents a necessary step towards a normalized, easily reproducible and reliable volumetric quantification of the perilymphatic and endolymphatic space in view of MR volumetric assessment of ELH. The proposed atlas lays the groundwork for state-of-the-art approaches (e.g., deep learning) and will be provided to the scientific community.

In practice, standard scheduling of parallel computing jobs almost always leaves significant portions of the available hardware unused, even with many jobs still waiting in the queue. The simple reason is that the resource requests of these waiting jobs are fixed and do not match the available, unused resources. However, with alternative but existing and well-established techniques it is possible to achieve a fully automated, adaptive parallelism that does not need pre-set, fixed resources. Here, we demonstrate that such an adaptively parallel program can run productively on a machine that is traditionally considered “full” and thus can indeed fill all such scheduling gaps, even in real-life situations on large supercomputers in which a fixed-size job could not have started.

Schwindel als haufiges Leitsymptom in der klinischen Praxis kann otologische, neurologische, internistische und psychiatrische Ursachen haben und stellt damit eine interdisziplinare Herausforderung dar. Durch eine systematische Anamnese und umfassende klinische Untersuchung gelingt in aller Regel eine eindeutige Zuordnung zu peripher-, zentral- oder nicht-vestibularen Krankheitsbildern. Wichtige Unterscheidungskriterien sind dabei der zeitliche Verlauf, die Art der Symptome, modulierende Faktoren und begleitende Symptome. Fur die klinische Untersuchung sind folgende Tests relevant: Kopfimpulstest, Untersuchung auf Spontannystagmus, Lagenystagmus, zentrale okulomotorische Zeichen und Romberg-Test. Dennoch gibt es neurootologische Grenzfalle, bei denen eine kombinierte peripher- und zentral-vestibulare Storung vorliegt. Ein Verschluss der A. cerebelli anterior inferior fuhrt zu einer Ischamie des Labyrinths und Zerebellums und verursacht dadurch einen akut auftretenden Schwindel mit unilateralem Horverlust. Bei rezidivierend auftretenden Schwindelattacken mit Ohrsymptomen und Kopfschmerzen gibt es ein Uberlappungssyndrom zwischen einem Morbus Meniere und einer vestibularen Migrane, das haufig einer dualen prophylaktischen Therapie bedarf. Patienten mit chronischem Schwankschwindel und Gangunsicherheit konnen unter dem Krankheitsbild CANVAS leiden, bei dem eine bilaterale Vestibulopathie zusammen mit einer Polyneuropathie und einem zerebellaren Syndrom auftritt. Chronische Schwindelbeschwerden mit peripher- und zentral-vestibularen Zeichen findet man auch bei Raumforderungen im Kleinhirnbruckenwinkel mit Kompression zentraler Strukturen. Zusammenfassend sollten in der Diagnostik bei Schwindel daher immer peripher- und zentral-vestibulare sowie okulomotorische Funktionen gepruft werden.

Orbital-free density functional theory (OFDFT) is both grounded in quantum physics and suitable for direct simulation of thousands of atoms. This article describes the application of OFDFT for materials research over roughly the past two decades, highlighting computational studies that would have been impractical (or impossible) to perform with other techniques. In particular, we review the growing body of simulations of solids and liquids that have been conducted with planewave-pseudopotential (or related) techniques. We also provide an updated account of the fundamentals of OFDFT, emphasizing aspects—such as nonlocal density functionals for computing the kinetic energy of noninteracting electrons—that enabled much of the application work. The article concludes with a discussion of the OFDFT frontier, which contains brief descriptions of other topics at the forefront of OFDFT research.

Surface hydrides (H–*s) play a crucial role in one of the heterogeneous mechanisms proposed for pyridine-catalyzed CO2 reduction on p-GaP electrodes. In this mechanism, H–* is transferred to adsorbed pyridine (Py*) concomitant with aqueous proton addition to form the active catalyst adsorbed dihydropyridine (DHP*), which in turn transfers hydride to CO2 and leads to its reduction. In this contribution, we test the validity of these hypothesized hydride transfers, determining whether or not H–* can participate in the mechanism of CO2 reduction on p-GaP electrodes. To this end, we use our previously developed cluster models with hybrid density functional theory and a mixed implicit–explicit solvation approach to calculate the thermodynamic hydricity of relevant species involved in the proposed mechanism. Overall, the proposed heterogeneous mechanism is supported by the computed thermodynamic hydricities. However, computed reaction and activation energies for H–* transfer from the surface reveal that H–* can...

The accuracy of local pseudopotentials (LPSs) is one of two major determinants of the fidelity of orbital-free density functional theory (OFDFT) simulations. We present a global optimization strategy for LPSs that enables OFDFT to reproduce solid and liquid properties obtained from Kohn-Sham DFT. Our optimization strategy can fit arbitrary properties from both solid and liquid phases, so the resulting globally optimized local pseudopotentials (goLPSs) can be used in solid and/or liquid-phase simulations depending on the fitting process. We show three test cases proving that we can (1) improve solid properties compared to our previous bulk-derived local pseudopotential generation scheme; (2) refine predicted liquid and solid properties by adding force matching data; and (3) generate a from-scratch, accurate goLPS from the local channel of a non-local pseudopotential. The proposed scheme therefore serves as a full and improved LPS construction protocol.

Embedding theories offer an elegant solution to overcome intrinsic algorithmic scaling and accuracy limitations of simulation methods. These theories also promise to achieve the accuracy of high-level electronic structure techniques at near the computational cost of much less accurate levels of theory by exploiting positive traits of multiple methods. Of crucial importance to fulfilling this promise is the ability to combine diverse theories in an embedding simulation. However, these methods may utilize different basis set and electron-ion potential representations. In this first part of a two-part account of implementing potential functional embedding theory (PFET) at a correlated wave function level, we discuss remedies to basis set and electron-ion potential discrepancies and assess the performance of the PFET scheme with mixed basis sets.

Few studies have evaluated exercise interventions for smokers with depression or other psychiatric comorbidities. This pilot study evaluated the potential role of supervised vigorous exercise as a smoking cessation intervention for depressed females. Thirty adult women with moderate-severe depressive symptoms were enrolled and randomly assigned to 12 weeks of thrice weekly, in person sessions of vigorous intensity supervised exercise at a YMCA setting (EX; n = 15) or health education (HE; n = 15). All participants received behavioral smoking cessation counseling and nicotine patch therapy. Assessments were done in person at baseline, at the end of 12 weeks of treatment, and at 6 months post-target quit date. Primary end points were exercise adherence (proportion of 36 sessions attended) and biochemically confirmed 7-day point prevalence abstinence at Week 12. Biomarkers of inflammation were explored for differences between treatment groups and between women who smoked and those abstinent at Week 12. Treatment adherence was high for both groups (72% for EX and 66% for HE; p = .55). The Week 12 smoking abstinence rate was higher for EX than HE (11/15 [73%] vs. 5/15 [33%]; p = .028), but no significant differences emerged at 6-month follow-up. Interleukin-6 levels increased more for those smoking than women abstinent at Week 12 (p = .040). Vigorous intensity supervised exercise is feasible and enhances short-term smoking cessation among depressed female smokers. Innovative and cost-effective strategies to bolster long-term exercise adherence and smoking cessation need evaluation in this population. Inflammatory biomarkers could be examined in future research as mediators of treatment efficacy. This preliminary study found that vigorous intensity supervised exercise is feasible and enhances short-term smoking cessation among depressed female smokers. This research addressed an important gap in the field. Despite decades of research examining exercise interventions for smoking cessation, few studies were done among depressed smokers or those with comorbid psychiatric disorders. A novel finding was increases in levels of a pro-inflammatory biomarker observed among women who smoked at the end of the intervention compared to those who did not.

Solid oxide fuel cells (SOFCs) efficiently generate electricity, but high operating temperatures (Top < 800 °C) limit their utility. Reducing Top requires mixed ion-electron conducting (MIEC) cathode materials. Density functional theory is used here to investigate the role of potassium substitutions in the MIEC material Sr1-xKxFeO3 (SKFO). We predict that such substitutions are endothermic. SrFeO3 and SKFO have nearly identical metallic electronic structures. Oxygen vacancy formation energies decrease by -0.2 eV when xK increases from 0 to 0.0625. SKFO is a promising SOFC MIEC cathode material; however, further experimental investigations must assess its long-term stability at the desired operating temperatures.

Mit dem Nachweis der onkologischen Sicherheit der haut- und nippelsparenden Mastektomie haben sich die Moglichkeiten der Brustrekonstruktion nach Mastektomie verbessert. Dies und die stetige Verbesserung der zur Verfugung stehenden Silikonimplantate haben die heterologe Brustrekonstruktion zu der am haufigsten durchgefuhrten Operationstechnik im Bereich der Wiederherstellungschirurgie nach Brustkrebs gemacht. Durch die zusatzliche Einfuhrung von supportiven alloplastischen Materialien wie synthetischen Netzen und azellularen dermalen Matrices besteht nun fur ein weiteres gut selektioniertes Patientenkollektiv eine Moglichkeit, die Indikationsstellung zur Implantatrekonstruktion nach Mastektomie zu erweitern. Dies ist ein erneuter Schritt, die Lebensqualitat fur diese Brustkrebspatientinnen zu verbessern. Es bleibt allerdings anzumerken, dass diese supportiven alloplastischen Produkte keine Losung fur alle Probleme darstellen und dementsprechend nur reflektiert eingesetzt werden durfen. Dieser Beitrag soll einen Uberblick uber die zur Verfugung stehenden Materialien geben und deren Einsatz kritisch diskutieren.

Postural instability is a frequent symptom of patients with idiopathic normal pressure hydrocephalus (iNPH), and might be due to the misperception of body verticality. The objective of this study was to assess the usefulness of the subjective body vertical (SBV) as a potential tool for diagnosing iNPH. Twenty patients with iNPH underwent tests of SBV in the pitch and roll planes before and after cerebrospinal fluid (CSF) drainage. Ten patients with other central gait disorders served as controls and also underwent tests for SBV. Before CSF drainage, patients with iNPH showed an impaired verticality perception in the pitch plane with a significant backward deviation of the SBV as compared to the control group (iNPH: mean ± SD −3.7 ± 3.6°; control group: −0.8 ± 2.2°; t value = −2.30, p t-test = 0.03). After CSF drainage, the SBV of the iNPH patients normalized for the pitch plane (−0.9 ± 1.9°). There was a correlation between the backward deviation of the SBV and the ventricular enlargement of the frontal horns (Evan’s index; r = −0.52; p Pearson = 0.02). An even stronger correlation was found with the enlargement of the third ventricle (Thalamus index; r = −0.64; p Pearson = 0.002). The new and clinically relevant finding of this study is that verticality perception of patients with iNPH is primarily impaired the pitch plane, and it improves after CSF drainage. This disturbance in pitch might be due to a bilateral central vestibular dysfunction of the thalamus. Determination of the SBV in pitch promises to increase diagnostic accuracy in the cases of suspected iNPH.

Introduction: Qualified training in senology is essential for maintaining adequate, high quality patient care. In order to meet the needs of doctors in training and those of the medical infrastructure it is necessary to assess the quality of training regularly, to enable its adaption and optimisation. Methods: We developed a comprehensive, 10 item online questionnaire to assess the quality of specialised training in senology. This questionnaire was sent to 4000 speciality trainees and young specialists countrywide via the DGGG newsletter and was accessible for over four weeks. Results: 111 obstetrics and gynaecology speciality trainees participated in this national survey, 79 % of whom were female. 33 % of participants were working at university hospitals, 29 % at hospitals offering maximal level care without an associated medical faculty, 37 % at hospitals offering primary and secondary level care and 2 % at gynaecology practices. 25 % of participants could imagine working in the field of senology in future. On average the current perception of general specialist training was satisfactory. Specialist trainees at university hospitals rated training in senology highest (score: 2.95) compared to those at other hospitals. A fixed rotation through a breast centre offering comprehensive advanced training was seen as a potential improvement to senology training. Conclusions: This is the first survey of specialised training in senology to be conducted in Germany. Results showed that there is significant potential for young doctors to enter the speciality in future. There are also significant differences in the perceived quality of senology training between training facilities. This survey aimed to determine the quality of specialised training at senology centres and hopes to contribute to a sustainable improvement in training. The intention is to continue to make senology attractive to gynaecologists and to ensure well-grounded training.