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1.
Strahlenther Onkol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748213

RESUMO

We present the rare case of a 42-year-old woman with oligometastatic lung adenocarcinoma in her first trimester of pregnancy who was treated for brain metastases with metastasectomy and intraoperative radiation therapy (IORT) using the INTRABEAM® system (Zeiss AG, Jena, Germany). This case underscores the potential of IORT in optimizing cancer treatment while safeguarding fetal health in pregnant patients.

2.
HNO ; 72(5): 303-309, 2024 May.
Artigo em Alemão | MEDLINE | ID: mdl-38587662

RESUMO

BACKGROUND: Digital transformation in curricular teaching in medicine comprises the use of digital teaching and learning formats as well as the transfer of digital skills for medical staff. Concepts of knowledge transfer and competency profiles also have to be adapted and transferred in advanced training due to necessary changes. OBJECTIVE: The aim of this study was an evaluation of the current state of digital transformation in otorhinolaryngology teaching in undergraduate and advanced training at otorhinolaryngology departments of university medical centers in Germany. MATERIALS AND METHODS: A questionnaire with nine questions on digital transformation was sent to the assistant professors of 37 national university ENT departments. The anonymous survey was conducted online via the online platform SurveyMonkey®. RESULTS: Of the contacted assistant professors, 86.5% participated in the survey. Teaching sessions on digital skills for medical students are part of the curriculum in only 25% of ENT departments. Digital teaching formats are used by half of the departments in undergraduate training. Only 56.25% of the assistant professors receive support to realize the changes required by digital transformation. In 40.62% of departments, the issue of digital transformation is broached during advanced training, but only 28.12% use digital teaching methods to train junior doctors. CONCLUSION: Aspects of digital transformation are implemented mainly in undergraduate education, partly driven by the COVID 19 pandemic. Overall, there is still considerable backlog in undergraduate and advanced training in ENT.


Assuntos
Currículo , Educação de Graduação em Medicina , Otolaringologia , Otolaringologia/educação , Alemanha , Humanos , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/tendências , Atitude do Pessoal de Saúde , Instrução por Computador/métodos , Inquéritos e Questionários , Docentes de Medicina/educação
3.
HNO ; 72(5): 367-374, 2024 May.
Artigo em Alemão | MEDLINE | ID: mdl-38578464

RESUMO

BACKGROUND: Analogous to the situation in other disciplines, digital ENT teaching made significant progress during the pandemic. Most ENT clinics nationwide were able to offer a complete virtual teaching program in time. Innovative teaching methods were also used early on. This was recognized in student teaching evaluations. Due to the expansion of virtual reality (VR) in medical teaching, even greater satisfaction should be expected through improved teaching quality. MATERIALS AND METHODS: Surveys were performed with students (n = 180) of the ENT block internship in the summer semester of 2023. The aim of the evaluation was to determine the students' satisfaction with and subjective effectiveness of the newly implemented VR digital teaching method for teaching ear anatomy and coniotomy. A survey was also carried out among resident physicians. RESULTS: The ENT teaching was perceived favorably by the students, with an average rating of 11.7 out of 15. The learning effectiveness and the value of VR in the ENT learning portfolio was evaluated varyingly by the students. The physicians' assessment was different, with a more positive perception. CONCLUSION: Virtual reality represents an innovative component in the teaching portfolio of otolaryngology. This new teaching method is viewed and accepted as a future-oriented tool. Remarkably, the physicians involved voted consistently positively, while the students gave more critical assessments and pointed out limitations in the individual and subjective areas. These findings are in contrast to the further development of innovative teaching methods demanded by student interest groups.


Assuntos
Otolaringologia , Estudantes de Medicina , Realidade Virtual , Otolaringologia/educação , Humanos , Alemanha , Inquéritos e Questionários , Instrução por Computador/métodos , Masculino , Feminino , Adulto , Adulto Jovem , Atitude do Pessoal de Saúde
4.
Opt Express ; 31(10): 16025-16034, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157690

RESUMO

We demonstrate monolithic high contrast gratings (MHCG) based on GaSb/AlAs0.08Sb0.92 epitaxial structures with sub-wavelength gratings enabling high reflection of unpolarized mid-infrared radiation at the wavelength range from 2.5 to 5 µm. We study the reflectivity wavelength dependence of MHCGs with ridge widths ranging from 220 to 984 nm and fixed 2.6 µm grating period and demonstrate that peak reflectivity of above 0.7 can be shifted from 3.0 to 4.3 µm for ridge widths from 220 to 984 nm, respectively. Maximum reflectivity of up to 0.9 at 4 µm can be achieved. The experiments are in good agreement with numerical simulations, confirming high process flexibility in terms of peak reflectivity and wavelength selection. MHCGs have hitherto been regarded as mirrors enabling high reflection of selected light polarization. With this work, we show that thoughtfully designed MHCG yields high reflectivity for both orthogonal polarizations simultaneously. Our experiment demonstrates that MHCGs are promising candidates to replace conventional mirrors like distributed Bragg reflectors to realize resonator based optical and optoelectronic devices such as resonant cavity enhanced light emitting diodes and resonant cavity enhanced photodetectors in the mid-infrared spectral region, for which epitaxial growth of distributed Bragg reflectors is challenging.

5.
Philos Trans A Math Phys Eng Sci ; 380(2216): 20210062, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-34923847

RESUMO

We review two algorithmic advances that bring us closer to reliable quantum simulations of model systems in high-energy physics and beyond on noisy intermediate-scale quantum (NISQ) devices. The first method is the dimensional expressivity analysis of quantum circuits, which allows for constructing minimal but maximally expressive quantum circuits. The second method is an efficient mitigation of readout errors on quantum devices. Both methods can lead to significant improvements in quantum simulations, e.g. when variational quantum eigensolvers are used. This article is part of the theme issue 'Quantum technologies in particle physics'.

6.
J Mater Sci Mater Med ; 33(11): 76, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36264396

RESUMO

Fractures of the paranasal sinuses often require surgical intervention. Persisting bone defects lead to permanent visible deformities of the facial contours. Bone substitutes for reconstruction of defects with simultaneous induction of new bone formation are not commercially available for the paranasal sinus. New materials are urgently needed and have to be tested in their future area of application. For this purpose critical size defect models for the paranasal sinus have to be developed. A ≥2.4 cm large bilateral circular defect was created in the anterior wall of the maxillary sinus in six sheep via an extraoral approach. The defect was filled with two types of an osteoconductive titanium scaffold (empty scaffold vs. scaffold filled with a calcium phosphate bone cement paste) or covered with a titanium mesh either. Sheep were euthanized after four months. All animals performed well, no postoperative complications occured. Meshes and scaffolds were safely covered with soft tissue at the end of the study. The initial defect size of ≥2.4 cm only shrunk minimally during the investigation period confirming a critical size defect. No ingrowth of bone into any of the scaffolds was observed. The anterior wall of the maxillary sinus is a region with low complication rate for performing critical size defect experiments in sheep. We recommend this region for experiments with future scaffold materials whose intended use is not only limited to the paranasal sinus, as the defect is challenging even for bone graft substitutes with proven osteoconductivity. Graphical abstract.


Assuntos
Substitutos Ósseos , Ovinos , Animais , Cimentos Ósseos , Titânio , Maxila/cirurgia , Fosfatos de Cálcio , Regeneração Óssea , Seio Maxilar/cirurgia
7.
Phys Rev Lett ; 126(11): 113201, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33798357

RESUMO

Above-threshold ionization spectra from cesium are measured as a function of the carrier-envelope phase (CEP) using laser pulses centered at 3.1 µm wavelength. The directional asymmetry in the energy spectra of backscattered electrons oscillates three times, rather than once, as the CEP is changed from 0 to 2π. Using the improved strong-field approximation, we show that the unusual behavior arises from the interference of few quantum orbits. We discuss the conditions for observing the high-order CEP dependence, and draw an analogy with time-domain holography with electron wave packets.

8.
Appl Opt ; 60(19): D43-D51, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263827

RESUMO

We present the inscription of narrow-linewidth fiber Bragg gratings (FBGs) into different types of multicore fibers (MCFs) using ultrashort laser pulses and the phase mask technique, which can act as notch filters. Such filters are required, e.g., to suppress light emitted by hydroxyl in the Earth's upper atmosphere, which disturbs ground-based observation of extraterrestrial objects in the near infrared. However, the inscription into a commercially available seven-core fiber showed a quite large core-to-core deviation of the resonance wavelength of up to 0.45 nm. Two options are presented to overcome this: first, we present the photo-treatment of the FBGs to tune the resonance wavelength, which allows for sufficient resonance shifts. Second, adapted MCFs containing 12 cores, arranged on a circle, are fabricated. For this, two different fabrication procedures were investigated, namely, the mechanical drilling of the preform for a rod-in-tube version as well as a stack-and-draw approach. Both adapted MCFs yielded significant improvements with core-to-core wavelength variations of the FBGs of only about 0.18 nm and 0.11 nm, respectively, sufficient to fulfill the requirements for astronomical filter applications as discussed above.

9.
HNO ; 69(3): 213-220, 2021 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-32929523

RESUMO

BACKGROUND: The corona crisis not only affects professional activities but also teaching and learning at universities. Buzzwords, such as e­learning and digitalization suggest the possibility of innovative teaching approaches that are readily available to solve the problems of teaching in the current COVID-19 pandemic. The current conversion to digital teaching is not primarily driven by didactic rationale or institutional strategy but by external circumstances. OBJECTIVE: The aim of the study was to determine the teaching situation at national university ENT clinics and academic teaching hospitals at the start of the virtual corona summer semester in 2020. MATERIAL AND METHODS: A specifically self-designed questionnaire regarding the local situation and conditions as well as nationwide scenarios was sent to all 39 national university ENT clinics and 20 ENT departments at academic teaching hospitals. RESULTS: A total of 31 university hospitals and 10 academic teaching hospitals took part in the survey. There were obvious discrepancies between available resources and effectively available digital teaching and learning contents. Further criticism was expressed regarding the communication with the medical faculty, the digital infrastructure and particularly the frequent lack of collaboration with central support facilities, such as media, didactics and datacenters. CONCLUSION: There are positive examples of successful transformation of classroom teaching to an exclusively virtual summer semester 2020 within the university ENT clinics; however, critical ratings of assistant professors and medical directors regarding the current teaching situation predominated. A time-critical strategic advancement is urgently needed.


Assuntos
COVID-19 , Universidades , Humanos , Aprendizagem , Pandemias , SARS-CoV-2 , Ensino
10.
Phys Rev Lett ; 125(24): 243001, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33412031

RESUMO

We demonstrate a widely applicable technique to absolutely calibrate the energy scale of x-ray spectra with experimentally well-known and accurately calculable transitions of highly charged ions, allowing us to measure the K-shell Rydberg spectrum of molecular O_{2} with 8 meV uncertainty. We reveal a systematic ∼450 meV shift from previous literature values, and settle an extraordinary discrepancy between astrophysical and laboratory measurements of neutral atomic oxygen, the latter being calibrated against the aforementioned O_{2} literature values. Because of the widespread use of such, now deprecated, references, our method impacts on many branches of x-ray absorption spectroscopy. Moreover, it potentially reduces absolute uncertainties there to below the meV level.

11.
Eur Cell Mater ; 39: 171-182, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32301500

RESUMO

Infections are often caused by pathobionts, endogenous bacteria that belong to the microbiota. Trauma and surgical intervention can allow bacteria to overcome host defences, ultimately leading to sepsis if left untreated. One of the main defence strategies of the immune system is the production of highly specific antibodies. In the present proof-of-concept study, plasma antibodies against 9 major pathogens were measured in sepsis patients, as an example of severe systemic infections. The binding of plasma antibodies to bacterial extracellular proteins was quantified using a semi-automated immunoblot assay. Comparison of the pathogen-specific antibody levels before and after infection showed an increase in plasma IgG in 20 out of 37 tested patients. This host-directed approach extended the results of pathogen-oriented microbiological and PCR diagnostics: a specific antibody response to additional bacteria was frequently observed, indicating unrecognised poly-microbial invasion. This might explain some cases of failed, seemingly targeted antibiotic treatment.


Assuntos
Anticorpos/imunologia , Sepse/imunologia , Sepse/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Formação de Anticorpos/imunologia , Estudos de Casos e Controles , Humanos , Imunoglobulina G/sangue , Cinética , Pessoa de Meia-Idade , Sepse/sangue , Especificidade da Espécie
12.
HNO ; 68(4): 257-262, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-31538215

RESUMO

A comprehensive societal change is currently taking place, which also includes the medical field. The often heard "digital transformation" is also fundamentally transforming the health care system familiar to us, including the medical schools. While the Masterplan 2020 includes changes in the medical school structure and in the curricular content, it unfortunately focuses on special competencies, e.g., communication or scientific work, but not on digitization. However, precisely these skills are becoming increasingly indispensable in daily routine work. The seminar "Digitization in otorhinolaryngology (ORL)" was incorporated as a pilot project in the students' curriculum of the Department of ORL, at the University of Freiburg/Germany: the 141 medical students completed and evaluated this seminar as part of their 2 week rotation in otorhinolaryngology during the fall semester 2017/2018. The content of the seminar mediated digital competencies on the basis of practical examples. The evaluation showed high interest of the students in the topic in general, but also in more detailed subitems of the digitization topic. The students were generally open-minded concerning digitization but also critical of the topic. The acceptance of this newly implemented seminar was clearly positive. Another positive side effect is that this teaching concept can be transferred to other disciplines. Hence, we suggest to consider the training of digital competencies when implementing the Masterplan 2020.


Assuntos
Análise de Dados , Otolaringologia , Estudantes de Medicina , Alfabetização Digital , Currículo , Humanos , Alfabetização , Otolaringologia/educação , Projetos Piloto
13.
Phys Rev Lett ; 122(19): 193602, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144948

RESUMO

Electrodynamical processes induced in complex systems like semiconductors by strong electromagnetic fields have traditionally been described using semiclassical approaches. Although these approaches allowed the investigation of ultrafast dynamics in solids culminating in multipetahertz electronics, they do not provide any access to the quantum-optical nature of the interaction, as they treat the driving field classically and unaffected by the interaction. Here, using a full quantum-optical approach, we demonstrate that the subcycle electronic response in a strongly driven semiconductor crystal is imprinted in the quantum state of the driving field resulting in nonclassical light states carrying the information of the interaction. This vital step towards strong-field ultrafast quantum electrodynamics unravels information inaccessible by conventional approaches and leads to the development of a new class of nonclassical light sources.

14.
Radiologe ; 59(9): 828-832, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31168771

RESUMO

BACKGROUND: The need for application expertise in natural language processing (NLP) is increasing in radiology. This way, in a complementary fashion to structured reporting using templates, the necessary database for quality assurance and continuous process optimization can be generated. OBJECTIVE: Possibilities and challenges of the application of NLP from the radiology point of view are explained. MATERIALS AND METHODS: The requirements and expectations for NLP systems are identified and demonstrated using a case study. RESULTS: For an effective use of this technology, NLP tasks for the interpretation of text using RadLex, an intuitive usage and feedback option as well as transparent quality of the NLP results are important. DISCUSSION: Using suitable NLP systems, targeted information can be extracted from large amounts of free text with manageable manual effort and high quality.


Assuntos
Processamento de Linguagem Natural , Radiologia , Radiografia
15.
Opt Express ; 26(25): 32417-32432, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30645409

RESUMO

We present the application of a confocal fluorescence microscope to the analysis of Yb-doped solid-state laser materials, with examples of Yb-doped crystals, photonic crystal fibers and fiber preforms made with different manufacturing processes. Beside the fluorescence lifetime image itself, a microscopic spectral fluorescence emission analysis is presented and spatially resolved emission cross sections are obtained. Doping concentration and its distributions and other laser optical parameters are measured, which help to analyze manufacturing steps. Further properties like photodarkening and saturation are addressed.

16.
Phys Rev Lett ; 120(6): 062501, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481214

RESUMO

We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9 GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02 GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.

17.
Radiologe ; 58(3): 236-240, 2018 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-29318348

RESUMO

BACKGROUND: The increasing digitization of our lives and work has also reached medicine and is changing the profession of medical doctors. The modern forms of communication and cooperation in everyday medical practice demand new skills and qualifications. GOALS: To enable future doctors to comply with this digitally competent profile, an innovative blended learning curriculum was developed and first implemented at the University Medical Center Mainz in summer semester 2017-Medicine in the Digital Age. MATERIALS AND METHODS: The teaching concept encompasses five modules, each consisting of an e­learning unit and a 3-hour classroom course. This publication presents the teaching concept, the initial implementation and evaluation of the module "Telemedicine". RESULTS: The competency development in the field of telemedicine showed a significant increase for the subcomponents "knowledge" and "skills". The neutral attitude towards telemedicine at the beginning of the module could be changed to a positive opinion after the session. DISCUSSION: The teaching of digital skills is a relevant component of future curriculum development in medical studies and also a challenge for continuing medical education.


Assuntos
Educação de Graduação em Medicina , Telemedicina , Currículo , Faculdades de Medicina
18.
Radiologe ; 58(8): 764-768, 2018 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-30014451

RESUMO

BACKGROUND: Due to the increasing demands in radiology, applications that enable quality assurance and continuous process optimization are required. OBJECTIVE: The principles of Natural Language Processing (NLP) as a computer-based method for structuring of free text reports are explained and application scenarios are sketched. MATERIALS UND METHODS: The structuring of free texts succeeds by several theories, linguistic techniques (word meanings, word context, negations), statistical methods with rules and currently with deep learning approaches. Medical encyclopedias, such as RadLex®, are suitable for coding findings. NLP was used in our own radiology clinic to check the quality of 3756 CT reports. RESULTS: In our case study, NLP proved to be a helpful, automated tool for internal quality testing. DISCUSSION: NLP offers numerous application scenarios for decision support and for quality management in radiology.


Assuntos
Sistemas de Informação em Radiologia , Radiologia , Processamento de Linguagem Natural , Radiografia
19.
Opt Express ; 25(13): 14892-14899, 2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28789071

RESUMO

We investigate the average power scaling of two diode-pumped Yb-doped fiber amplifiers emitting a diffraction-limited beam. The first fiber under investigation with a core diameter of 30 µm was able to amplify a 10 W narrow linewidth seed laser up to 2.8 kW average output power before the onset of transverse mode instabilities (TMI). A further power scaling was achieved using a second fiber with a smaller core size (23µm), which allowed for a narrow linewidth output power of 3.5 kW limited by stimulated Brillouin scattering (SBS). We mitigated SBS using a spectral broadening mechanism, which allowed us to further increase the output power to 4.3 kW only limited by the available pump power. Up to this power level, a high slope efficiency of 90% with diffraction-limited beam quality and without any sign of TMI or stimulated Raman scattering for a spectral dynamic range of higher than -80 dB was obtained.

20.
Br J Anaesth ; 119(4): 616-625, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121280

RESUMO

BACKGROUND: There is growing evidence that beta-blockade may reduce mortality in selected patients with sepsis. However, it is unclear if a pre-existing, chronic oral beta-blocker therapy should be continued or discontinued during the acute phase of severe sepsis and septic shock. METHODS: The present secondary analysis of a prospective observational single centre trial compared patient and treatment characteristics, length of stay and mortality rates between adult patients with severe sepsis or septic shock, in whom chronic beta-blocker therapy was continued or discontinued, respectively. The acute phase was defined as the period ranging from two days before to three days after disease onset. Multivariable Cox regression analysis was performed to compare survival outcomes in patients with pre-existing chronic beta-blockade. RESULTS: A total of 296 patients with severe sepsis or septic shock and pre-existing, chronic oral beta-blocker therapy were included. Chronic beta-blocker medication was discontinued during the acute phase of sepsis in 129 patients and continued in 167 patients. Continuation of beta-blocker therapy was significantly associated with decreased hospital (P=0.03), 28-day (P=0.04) and 90-day mortality rates (40.7% vs 52.7%; P=0.046) in contrast to beta-blocker cessation. The differences in survival functions were validated by a Log-rank test (P=0.01). Multivariable analysis identified the continuation of chronic beta-blocker therapy as an independent predictor of improved survival rates (HR = 0.67, 95%-CI (0.48, 0.95), P=0.03). CONCLUSIONS: Continuing pre-existing chronic beta-blockade might be associated with decreased mortality rates up to 90 days in septic patients.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Sepse/mortalidade , Idoso , Comorbidade , Feminino , Alemanha , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque Séptico/mortalidade , Tempo , Resultado do Tratamento
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