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1.
Med Klin Intensivmed Notfmed ; 119(Suppl 1): 1-50, 2024 May.
Artículo en Alemán | MEDLINE | ID: mdl-38625382

RESUMEN

In Germany, physicians qualify for emergency medicine by combining a specialty medical training-e.g. internal medicine-with advanced training in emergency medicine according to the statutes of the State Chambers of Physicians largely based upon the Guideline Regulations on Specialty Training of the German Medical Association. Internal medicine and their associated subspecialities represent an important column of emergency medicine. For the internal medicine aspects of emergency medicine, this curriculum presents an overview of knowledge, skills (competence levels I-III) as well as behaviours and attitudes allowing for the best treatment of patients. These include general aspects (structure and process quality, primary diagnostics and therapy as well as indication for subsequent treatment; resuscitation room management; diagnostics and monitoring; general therapeutic measures; hygiene measures; and pharmacotherapy) and also specific aspects concerning angiology, endocrinology, diabetology and metabolism, gastroenterology, geriatric medicine, hematology and oncology, infectiology, cardiology, nephrology, palliative care, pneumology, rheumatology and toxicology. Publications focussing on contents of advanced training are quoted in order to support this concept. The curriculum has primarily been written for internists for their advanced emergency training, but it may generally show practising emergency physicians the broad spectrum of internal medicine diseases or comorbidities presented by patients attending the emergency department.


Asunto(s)
Curriculum , Medicina de Emergencia , Servicio de Urgencia en Hospital , Medicina Interna , Medicina Interna/educación , Humanos , Alemania , Medicina de Emergencia/educación , Competencia Clínica , Educación de Postgrado en Medicina
2.
J Colloid Interface Sci ; 648: 633-643, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37321082

RESUMEN

Most analytical techniques used to study the surface chemical properties of superparamagnetic iron oxide nanoparticles (SPIONs) are barely suitable for in situ investigations in liquids, where SPIONs are mostly applied for hyperthermia therapy, diagnostic biosensing, magnetic particle imaging or water purification. Magnetic particle spectroscopy (MPS) can resolve changes in magnetic interactions of SPIONs within seconds at ambient conditions. Herein, we show that by adding mono- and divalent cations to citric acid capped SPIONs, the degree of agglomeration can be utilized to study the selectivity of cations towards surface coordination motifs via MPS. A favored chelate agent, like ethylenediaminetetraacetic acid (EDTA) for divalent cations, removes cations from coordination sites on the SPION surface and causes redispersion of agglomerates. The magnetic determination thereof represents what we call a "magnetically indicated complexometric titration". The relevance of agglomerate sizes for the MPS signal response is studied on a model system of SPIONs and the surfactant cetrimonium bromide (CTAB). Analytical ultracentrifugation (AUC) and cryogenic transmission electron microscopy (cryo-TEM) reveal that large micron-sized agglomerates are required to significantly change the MPS signal response. With this work, a fast and easy-to-use characterization method to determine surface coordination motifs of magnetic nanoparticles in optically dense media is demonstrated.

3.
J Chem Phys ; 158(14): 144305, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37061488

RESUMEN

While the dissociative recombination (DR) of ground-state molecular ions with low-energy free electrons is generally known to be exothermic, it has been predicted to be endothermic for a class of transition-metal oxide ions. To understand this unusual case, the electron recombination of titanium oxide ions (TiO+) with electrons has been experimentally investigated using the Cryogenic Storage Ring. In its low radiation field, the TiO+ ions relax internally to low rotational excitation (≲100 K). Under controlled collision energies down to ∼2 meV within the merged electron and ion beam configuration, fragment imaging has been applied to determine the kinetic energy released to Ti and O neutral reaction products. Detailed analysis of the fragment imaging data considering the reactant and product excitation channels reveals an endothermicity for the TiO+ dissociative electron recombination of (+4 ± 10) meV. This result improves the accuracy of the energy balance by a factor of 7 compared to that found indirectly from hitherto known molecular properties. Conversely, the present endothermicity yields improved dissociation energy values for D0(TiO) = (6.824 ± 0.010) eV and D0(TiO+) = (6.832 ± 0.010) eV. All thermochemistry values were compared to new coupled-cluster calculations and found to be in good agreement. Moreover, absolute rate coefficients for the electron recombination of rotationally relaxed ions have been measured, yielding an upper limit of 1 × 10-7 cm3 s-1 for typical conditions of cold astrophysical media. Strong variation of the DR rate with the TiO+ internal excitation is predicted. Furthermore, potential energy curves for TiO+ and TiO have been calculated using a multi-reference configuration interaction method to constrain quantum-dynamical paths driving the observed TiO+ electron recombination.

4.
Schmerz ; 2023 Jan 02.
Artículo en Alemán | MEDLINE | ID: mdl-36592212

RESUMEN

BACKGROUND: Current guidelines recommend a personalized, multimodal, and interdisciplinary approach for the treatment of chronic pain. Already in the acute treatment of postoperative pain, it can be useful to minimize risk factors for chronification. Auricular vagus nerve stimulation (aVNS) could be an effective non-drug therapy for the treatment of chronic and acute pain. AIM OF THE WORK: The aim of this systematic review is to evaluate the clinical efficacy of aVNS in chronic and acute pain as well as its effect on medication intake. MATERIALS AND METHODS: A systematic literature search was carried out on the application of auricular electrical stimulation in chronic and acute pain. Studies were classified according to their level of evidence and evaluated via the Jadad scale as well as their scientific validity, and then analyzed in terms of indication, method, stimulation parameters, duration of treatment, efficacy, and safety. RESULTS: Twenty studies on chronic pain indications, ten studies on acute postoperative pain, as well as seven studies on experimental acute pain were identified and analyzed. The search revealed a total of n = 1105 aVNS-treated patients. The best evidence on the efficacy of aVNS is available for the indications chronic low back pain, chronic cervical syndrome, chronic abdominal pain, and chronic migraine as well as acute postoperative pain in oocyte aspiration, laparoscopic nephrectomy, and open colorectal surgery. Additionally a significant reduction in analgesic or opiate intake was evident in most studies. In three randomized controlled trials in chronic pain patients, a sustainable pain reduction over a period of up to 12 months was shown. Overall, aVNS was very well tolerated. CONCLUSION: This review indicates that aVNS can be a complementary and effective non-drug treatment for patients with chronic and acute postoperative pain. Future studies in these indications should focus on standardizing and optimizing treatment parameters, inclusion of quality-of-life outcome parameters, and longer follow-up periods to better understand the sustainable therapeutic effect of aVNS.

5.
Materials (Basel) ; 17(1)2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38204005

RESUMEN

Additive manufacturing allows for the production of complex components using various types of materials such as plastics, metals and ceramics without the need for molding tools. In the field of high-performance polymers, semi-crystalline polymers such as polyetheretherketone (PEEK) or amorphous polymers such as polyetherimide (PEI) are already successfully applied. Contrary to semi-crystalline and amorphous polymers, thermotropic liquid crystalline polymers (LCPs) do not change into an isotropic liquid during melting. Instead, they possess anisotropic properties in their liquid phase. Within the scope of this work, this special group of polymers was investigated with regard to its suitability for processing by means of fused filament fabrication. Using an LCP with a low melting temperature of around 280 °C is compared to processing an LCP that exhibits a high melting temperature around 330 °C. In doing so, it was revealed that the achievable mechanical properties strongly depend on the process parameters such as the direction of deposition, printing temperature, printing speed and layer height. At a layer height of 0.10 mm, a Young's modulus of 27.3 GPa was achieved. Moreover, by employing an annealing step after the printing process, the tensile strength could be increased up to 406 MPa at a layer height of 0.15 mm. Regarding the general suitability for FFF as well as the achieved uniaxial mechanical properties, the LCP with a low melting temperature was advantageous compared to the LCP with a high melting temperature.

6.
Cureus ; 14(7): e27202, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36039223

RESUMEN

Schizoaffective disorder, bipolar type is a chronic mental health disorder that may manifest as mania. Clozapine is effective in treating acute mania and in achieving mood stabilization. However, on rare occasions, the use of clozapine has been associated with cardiotoxicity. Here, we present a case of a 31-year-old man who at baseline is known to have schizoaffective disorder, bipolar type, and cannabis dependence and was admitted to our hospital with a psychotic relapse. He was treated with clozapine, uptitrated to a maximum daily dose of 200mg twice daily by day 10. Thereafter he became febrile and experienced malaise, myalgias, and chest pain. He was noted on electrocardiogram to have sinus tachycardia without ischemic changes. In this context, he had a troponin leak, increased white blood cell count, serologies and cultures were negative and chest x-ray revealed no acute disease of the chest. Due to the suspicion of clozapine-induced cardiotoxicity, a transthoracic echocardiogram was done, which revealed mildly depressed left ventricular (LV) systolic function without pericardial effusion. Thereafter, clozapine was withdrawn and switched to lithium. Additionally, the cardioselective, metoprolol tartrate was initiated. Within 36-48 hours, he had resolution of symptoms and remained cardiovascularly stable. Clozapine uncommonly causes cardiotoxicity and early features may be non-specific. Awareness of this and recognizing early features aids in reducing the associated cardiovascular morbidity and mortality.

7.
Rev Sci Instrum ; 93(6): 063302, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35777995

RESUMEN

For sensitive studies of molecular ions in electrostatic storage rings, the exact knowledge of the isobaric composition of stored beams from a variety of ion sources is essential. Conventional mass-filtering techniques are often inefficient to resolve the beam components. Here, we report the first isochronous mass spectrometry in an electrostatic storage ring, which offers a high mass resolution of Δm/m < 1 × 10-5 even for heavy molecular species with m > 100 u and uncooled ion beams. Mass contaminations can be resolved and identified at relative fractions down to 0.02%.

8.
J Synchrotron Radiat ; 29(Pt 3): 794-806, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35511012

RESUMEN

The advent of hard X-ray free-electron lasers enables nanoscopic X-ray imaging with sub-picosecond temporal resolution. X-ray grating interferometry offers a phase-sensitive full-field imaging technique where the phase retrieval can be carried out from a single exposure alone. Thus, the method is attractive for imaging applications at X-ray free-electron lasers where intrinsic pulse-to-pulse fluctuations pose a major challenge. In this work, the single-exposure phase imaging capabilities of grating interferometry are characterized by an implementation at the I13-1 beamline of Diamond Light Source (Oxfordshire, UK). For comparison purposes, propagation-based phase contrast imaging was also performed at the same instrument. The characterization is carried out in terms of the quantitativeness and the contrast-to-noise ratio of the phase reconstructions as well as via the achievable spatial resolution. By using a statistical image reconstruction scheme, previous limitations of grating interferometry regarding the spatial resolution can be mitigated as well as the experimental applicability of the technique.

9.
Phys Rev Lett ; 128(18): 183402, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35594107

RESUMEN

We present state-selected measurements of rotational cooling and excitation rates of CH^{+} molecular ions by inelastic electron collisions. The experiments are carried out at a cryogenic storage ring, making use of a monoenergetic electron beam at matched velocity in combination with state-sensitive laser dissociation of the CH^{+} ions for simultaneous monitoring of the rotational level populations. Employing storage times of up to 600 s, we create conditions where electron-induced cooling to the J=0 ground state dominates over radiative relaxation, allowing for the experimental determination of inelastic electron collision rates to benchmark state-of-the-art theoretical calculations. On a broader scale, our experiments pave the way to probe inelastic electron collisions for a variety of molecular ions relevant in various plasma environments.

10.
J Imaging ; 7(9)2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34564104

RESUMEN

X-ray backlighters allow the capture of sharp images of fast dynamic processes due to extremely short exposure times. Moiré imaging enables simultaneously measuring the absorption and differential phase-contrast (DPC) of these processes. Acquiring images with one single shot limits the X-ray photon flux, which can result in noisy images. Increasing the photon statistics by repeating the experiment to gain the same image is not possible if the investigated processes are dynamic and chaotic. Furthermore, to reconstruct the DPC and transmission image, an additional measurement captured in absence of the object is required. For these reference measurements, shot-to-shot fluctuations in X-ray spectra and a source position complicate the averaging of several reference images for noise reduction. Here, two approaches of processing multiple reference images in combination with one single object image are evaluated regarding the image quality. We found that with only five reference images, the contrast-to-noise ratio can be improved by approximately 13% in the DPC image. This promises improvements for short-exposure single-shot acquisitions of rapid processes, such as laser-produced plasma shock-waves in high-energy density experiments at backlighter X-ray sources such as the PHELIX high-power laser facility.

11.
Sci Rep ; 11(1): 4574, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33633184

RESUMEN

Detailed imaging of the three-dimensionally complex architecture of xylary plants is important for studying biological and mechanical functions of woody plants. Apart from common two-dimensional microscopy, X-ray micro-computed tomography has been established as a three-dimensional (3D) imaging method for studying the hydraulic function of wooden plants. However, this X-ray imaging method can barely reach the resolution needed to see the minute structures (e.g. pit membrane). To complement the xylem structure with 3D views at the nanoscale level, X-ray near-field nano-holotomography (NFH) was applied to analyze the wood species Pinus sylvestris and Fagus sylvatica. The demanded small specimens required focused ion beam (FIB) application. The FIB milling, however, influenced the image quality through gallium implantation on the cell-wall surfaces. The measurements indicated that NFH is appropriate for imaging wood at nanometric resolution. With a 26 nm voxel pitch, the structure of the cell-wall surface in Pinus sylvestris could be visualized in genuine detail. In wood of Fagus sylvatica, the structure of a pit pair, including the pit membrane, between two neighboring fibrous cells could be traced tomographically.

12.
Schmerz ; 35(2): 124-129, 2021 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-33447917

RESUMEN

Radiofrequency denervation has been established for many years as an important minimally invasive procedure for the treatment of chronic pain conditions. Positive experiences of many users for various indications are contrasted by a nonuniform evidence. With meticulous patient selection and correct assessment of the indications a longer term reduction of pain, a reduced need for analgesics and an improvement in the quality of life can be achieved. The aim of this interdisciplinary position paper is to present the value of radiofrequency denervation in the treatment of chronic pain. The summarized recommendations of the expert group are based on the available evidence and on the clinical experiences of Austrian centers that frequently implement the procedure. The position paper contains recommendations on patient selection and proven indications. We discribe safety aspects, complications, side effects and contraindications.


Asunto(s)
Dolor Crónico , Dolor de la Región Lumbar , Articulación Cigapofisaria , Austria , Dolor Crónico/terapia , Desnervación , Humanos , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares , Calidad de Vida , Resultado del Tratamiento
13.
Cardiol Ther ; 9(2): 467-478, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32638266

RESUMEN

INTRODUCTION: Apixaban has been shown to be superior to warfarin in patients with non-valvular atrial fibrillation in the randomized ARISTOTLE trial and its use is recommended in current guidelines. There are only scarce data about its use, efficacy, and safety in unselected patients in Germany. METHODS AND RESULTS: The APAF registry is a prospective non-interventional study enrolling 5015 patients with non-valvular atrial fibrillation. Of these, 1349 (26.9%) patients were initially treated with apixaban and followed up at 3 and 12 months. The dose of apixaban used was 1 × 2.5 mg in 1.6%, 2 × 2.5 mg in 30.4%, and 2 × 5 mg daily in 68.0% of patients, respectively. Inappropriate underdosing of apixaban was observed in 22.3%, mostly in elderly patients with higher HAS-BLED Score and a history of bleeding. Persistence to apixaban after 1 year was 88.6%, while the dose was changed in 3.7% of patients. Switching to other NOACs or VKAs occurred in 5.1%. After 12 months, all-cause mortality was 5.0%, non-fatal stroke occurred in 0.4%, non-fatal myocardial infarction in 0.6%, ISTH major bleeding in 0.8%, moderate or minor bleeding in 4.3% of patients, respectively. CONCLUSIONS: In this prospective experience in unselected patients with atrial fibrillation, persistence to apixaban was high, and efficacy and safety were comparable to the results in clinical trials, supporting its use in clinical practice.

14.
Opt Express ; 28(9): 13553-13568, 2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32403827

RESUMEN

The combination of grating-based phase-contrast imaging with X-ray microscopy can result in a complicated image formation. Generally, transverse shifts of the interference fringes are nonlinearly dependent on phase differences of the measured wave front. We present an iterative reconstruction scheme based on a regularized maximum likelihood cost function that fully takes this dependency into account. The scheme is validated by numerical simulations. It is particularly advantageous at low photon numbers and when the premises for deconvolution-based reconstructions are not met. Our reconstruction scheme hence enables a broader applicability of X-ray grating interferometry in imaging and wave front sensing.

15.
J Imaging ; 6(7)2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-34460656

RESUMEN

For imaging events of extremely short duration, like shock waves or explosions, it is necessary to be able to image the object with a single-shot exposure. A suitable setup is given by a laser-induced X-ray source such as the one that can be found at GSI (Helmholtzzentrum für Schwerionenforschung GmbH) in Darmstadt (Society for Heavy Ion Research), Germany. There, it is possible to direct a pulse from the high-energy laser Petawatt High Energy Laser for Heavy Ion eXperiments (PHELIX) on a tungsten wire to generate a picosecond polychromatic X-ray pulse, called backlighter. For grating-based single-shot phase-contrast imaging of shock waves or exploding wires, it is important to know the weighted mean energy of the X-ray spectrum for choosing a suitable setup. In propagation-based phase-contrast imaging the knowledge of the weighted mean energy is necessary to be able to reconstruct quantitative phase images of unknown objects. Hence, we developed a method to evaluate the weighted mean energy of the X-ray backlighter spectrum using propagation-based phase-contrast images. In a first step wave-field simulations are performed to verify the results. Furthermore, our evaluation is cross-checked with monochromatic synchrotron measurements with known energy at Diamond Light Source (DLS, Didcot, UK) for proof of concepts.

16.
Biomed Tech (Berl) ; 65(2): 237-241, 2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-31525155

RESUMEN

This study comprised two experiments: (1) the reliability of a novel optical three-dimensional (3D) volumetric measurement system (BODYTRONIC® 600) for the assessment of lower limb circumference and volume; (2) the comparison of data obtained from BODYTRONIC® 600 with that provided by computed tomography (CT) for accuracy estimation. Reliability was assessed in 20 healthy subjects. Accuracy was determined by comparing the deviations in the surface topology of two 3D models obtained from BODYTRONIC® 600 and CT. Reliability was very high for leg circumference measures [coefficient of variations (CVs) range 0.3%-1.3%] and slightly lower for foot circumference (CVs around 2.0%). Reliability of leg volume was also found to be very high (CVs ≤ 2.5%). Differences in surface topology between BODYTRONIC® 600 and CT were primarily below 1 mm indicating high accuracy. The volumes of the foot were higher (range 0.9%-1.7%) and that of the leg, lower (range 1.0%-1.3%) compared to CT. The BODYTRONIC® 600 system provides fast, highly reliable and accurate measures of lower limb circumference and volume and can be considered as a valuable measurement tool for use in various research and clinical applications.


Asunto(s)
Imagenología Tridimensional , Tomografía Computarizada por Rayos X/instrumentación , Humanos , Imagenología Tridimensional/métodos , Extremidad Inferior , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X/métodos
17.
Science ; 365(6454): 676-679, 2019 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-31320559

RESUMEN

The epoch of first star formation in the early Universe was dominated by simple atomic and molecular species consisting mainly of two elements: hydrogen and helium. Gaining insight into this constitutive era requires a thorough understanding of molecular reactivity under primordial conditions. We used a cryogenic ion storage ring combined with a merged electron beam to measure state-specific rate coefficients of dissociative recombination, a process by which electrons destroy molecular ions. We found a pronounced decrease of the electron recombination rates for the lowest rotational states of the helium hydride ion (HeH+), compared with previous measurements at room temperature. The reduced destruction of cold HeH+ translates into an enhanced abundance of this primordial molecule at redshifts of first star and galaxy formation.

18.
J Community Genet ; 10(4): 523-530, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30927239

RESUMEN

The significance of human biorepositories for modern medical research, particularly for comprehensive population-based genetic analyses, is constantly growing. While large and centralized institutions are usually considered best suited to meet the increasing demand for high-quality "biobanks," most medical research institutions still host rather heterogeneous and fragmented biobanking activities, undertaken by clinical departments with oftentimes rather different scientific scope. Undoubtedly, most clinicians and medical researchers would appreciate infrastructural support in terms of the storage and handling of their biosamples, but they are also likely to expect access to their samples avoiding extensive formal requirements. We report on the establishment of the PopGen 2.0 Network (P2N), an overarching alliance of initially seven biobanks from Northern Germany which adopted a joint but lean governance structure and use-and-access policy for their samples and data. In addition, the members of P2N have pursued an intense collaboration on ethical, legal and social issues and maintain a common IT infrastructure. The implementation of P2N has substantially improved the prospects of biobank-based research at the participating institutions. The network may thus serve as a role model for similar initiatives geared at linking pre-existing biorepositories for the benefit of research quality, efficiency, and transparency.

19.
Stud Health Technol Inform ; 253: 70-74, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30147043

RESUMEN

A record linkage algorithm tries to identify records which belong to the same individual. We analyze the matching behavior of an approach used in the E-PIX matching tool on the very limited attribute set of first name, last name, date of birth and sex. Our benchmark set contains almost 37,000 records from the Popgen biobank. We develop a model which allows us to predict the workload on clerical review for data sets growing up to a factor of 10 or even more, without the need for a data set of this size. Based on this model we show two parameter sets with comparable detection rate of true duplicates, but where only one of them scales well on growing data sets. Our model provides realistic example records for each predicted matching of an upscaled data set. Thus, it enables to identify the parameters which need to be adjusted in order to improve the quality of the matching candidates. We also show that unreviewed merging of records is prone to homonym errors on data sets with 200,000 records and the limited attribute set above, while the merged record pairs are obviously different in clerical review.


Asunto(s)
Algoritmos , Almacenamiento y Recuperación de la Información , Exactitud de los Datos , Registro Médico Coordinado
20.
Phys Rev Lett ; 120(25): 253001, 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29979073

RESUMEN

A method is presented to monitor the internal energy distribution of cluster anions via delayed electron detachment by pulsed photoexcitation and demonstrated on Co_{4}^{-} in an electrostatic ion beam trap. In a cryogenic operation, we calibrate the detachment delay to internal energy. By laser frequency scans, at room temperature, we reconstruct the time-dependent internal energy distribution of the clusters. The mean energies of ensembles from a cold and a hot ion source both approach thermal equilibrium. Our data yield a radiative emission law and the absorptivity of the cluster for thermal radiation.

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