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PURPOSE: To investigate multiple deep learning methods for automated segmentation (auto-segmentation) of the parotid glands, submandibular glands, level II and level III lymph nodes on magnetic resonance imaging (MRI). Outlining radiosensitive organs on images used to assist radiation therapy (radiotherapy) of patients with head and neck cancer (HNC) is a time-consuming task, in which variability between observers may directly impact on patient treatment outcomes. Auto-segmentation on computed tomography imaging has been shown to result in significant time reductions and more consistent outlines of the organs at risk. METHODS: Three convolutional neural network (CNN) based auto-segmentation architectures were developed using manual segmentations and T2 weighted MRI images provided from the AAPM RT-MAC challenge dataset (n = 31). Auto-segmentation performance was evaluated with segmentation similarity and surface distance metrics on the RT-MAC dataset with institutional manual segmentations (n = 10). The generalisability of the auto-segmentation methods was assessed on an institutional MRI dataset (n = 10). RESULTS: Auto-segmentation performance on the RT-MAC images with institutional segmentations was higher than previously reported MRI methods for the parotid glands (dice: 0.860 ± 0.067, mean surface distance: 1.33 ± 0.40 mm) and the first report of MRI performance for submandibular glands (dice: 0.830 ± 0.032, mean surface distance: 1.16 ± 0.47 mm). We demonstrate that high-resolution auto-segmentations with improved geometric accuracy can be generated for the parotid and submandibular glands by cascading a localiser CNN and a cropped high-resolution CNN. Improved mean surface distances were observed between automatic and manual segmentations of the submandibular glands when a low-resolution auto-segmentation was used as prior knowledge in the second stage CNN. Reduced auto-segmentation performance was observed on our institutional MRI dataset when trained on external RT-MAC images; only the parotid gland auto-segmentations were considered clinically feasible for manual correction (dice: 0.775 ± 0.105, mean surface distance: 1.20 ± 0.60 mm). CONCLUSION: This work demonstrates that CNNs are a suitable method to auto-segment the parotid and submandibular glands on MRI images of patients with HNC, and that cascaded CNNs can generate high resolution segmentations with improved geometric accuracy. Deep learning methods may be suitable for auto-segmentation of the parotid glands on T2 weighted MRI images from different scanners, but further work is required to improve the performance and generalisability of these methods for auto-segmentation of the submandibular glands and lymph nodes. This article is protected by copyright. All rights reserved.

Purpose This study focused on determining risks from stereotactic radiotherapy using flattening filter‐free (FFF) beams for patients with cardiac implantable electronic device (CIEDs). Two strategies were employed: a) a retrospective analysis of patients with CIEDs who underwent stereotactic radiosurgery (SRS)/SBRT at the Peter MacCallum Cancer Centre between 2014 and 2018 and b) an experimental study on the impact of FFF beams on CIEDs. Methods A retrospective review was performed. Subsequently, a phantom study was performed using 30 fully functional explanted CIEDs from two different manufacturers. Irradiation was carried out in a slab phantom with 6‐MV and 10‐MV FFF beams. First, a repetition‐rate test (RRT) with a range of beam pulse frequencies was conducted. Then, multifraction SBRT (48 Gy/4 Fx) and single‐fraction SBRT (28 Gy/1 Fx) treatment plans were used for lung tumors delivered to the phantom. Results Between 2014 and 2018, 13 cases were treated with an FFF beam (6 MV, 1400 MU/min or 10 MV, 2400 MU/min), and 15 cases were treated with a flattening filter (FF) beam (6 MV, 600 MU/min). All the devices were positioned outside the treatment field at a distance of more than 5 cm, except for one case, and no failures were reported due to SBRT/SRS. In the phantom rep‐rate tests, inappropriate sensing occurred, starting at a rep‐rate of 1200 MU/min. Cardiac implantable electronic device anomalies during and after delivering VMAT‐SBRT with a 10‐MV FFF beam were observed. Conclusions The study showed that caution should be paid to managing CIED patients when they undergo SBRT using FFF beams, as it is recommended by AAPM TG‐203. Correspondingly, it was found that for FFF beams although there is small risk from dose‐rate effects, delivering high dose of radiation with beam energy greater than 6 MV and high‐dose rate to CIEDs positioned in close vicinity of the PTV may present issues.

Radiomics is a promising technique for discovering image based biomarkers of therapy response in cancer. Reproducibility of radiomics features is a known issue that is addressed by the image biomarker standardisation initiative (IBSI), but it remains challenging to interpret previously published radiomics signatures. This study investigates the reproducibility of radiomics features calculated with two widely used radiomics software packages (IBEX, MaZda) in comparison to an IBSI compliant software package (PyRadiomics). Intensity histogram, shape and textural features were extracted from 334 diffusion weighted magnetic resonance images of 59 head and neck cancer (HNC) patients from the PREDICT-HN observational radiotherapy study. Based on name and linear correlation, PyRadiomics shares 83 features with IBEX and 49 features with MaZda, a sub-set of well correlated features are considered reproducible (IBEX: 15 features, MaZda: 18 features). We explore the impact of including non-reproducible radiomics features in a HNC radiotherapy response model. It is possible to classify equivalent patient groups using radiomic features from either software, but only when restricting the model to reliable features using a correlation threshold method. This is relevant for clinical biomarker validation trials as it provides a framework to assess the reproducibility of reported radiomic signatures from existing trials.

Radiomics is a promising technique for discovering image based biomarkers of therapy response in cancer. Reproducibility of radiomics features is a known issue that is addressed by the image biomarker standardisation initiative (IBSI), but it remains challenging to interpret previously published radiomics signatures. This study investigates the reproducibility of radiomics features calculated with two widely used radiomics software packages (IBEX, MaZda) in comparison to an IBSI compliant software package (PyRadiomics). Intensity histogram, shape and textural features were extracted from 334 diffusion weighted magnetic resonance images of 59 head and neck cancer (HNC) patients from the PREDICT-HN observational radiotherapy study. Based on name and linear correlation, PyRadiomics shares 83 features with IBEX and 49 features with MaZda, a sub-set of well correlated features are considered reproducible (IBEX: 15 features, MaZda: 18 features). We explore the impact of including non-reproducible radiomics features in a HNC radiotherapy response model. It is possible to classify equivalent patient groups using radiomic features from either software, but only when restricting the model to reliable features using a correlation threshold method. This is relevant for clinical biomarker validation trials as it provides a framework to assess the reproducibility of reported radiomic signatures from existing trials.

Biomass for non-food applications is considered as a substitute for petro-based materials such as expanded polystyrene (EPS). This research analyzes physical properties of an EPS containing commercial bonded leveling compound (BLC) which was substituted with cup plant (Silphium perfoliatum L.) biomass. Cup plant is a high-yielding biomass plant with several ecological benefits that is yet mainly used for biogas production. Furthermore, the high amount of parenchyma in senescent biomass with its EPS-like structure could be a possible substitute for petrochemical foams in lightweight aggregates. The natural variation in parenchyma content of several European cup plant accessions is promising, regarding the development of cultivars with suitable biomass properties for the proposed material use. Two binders with different proportions of cup plant and EPS were used to produce samples of BLC for thermal conductivity and compression strength tests. The compression strength of 0.92 N mm−2 and a thermal conductivity of 84 mW m−1 K−1 were analyzed and comparable to the commercial BLC. The thermal conductivity within the tested borders appears nearly independent of the biomass content. With increasing cup plant content, the shape characteristics of the lightweight aggregate mix changes towards more elongated aggregates. The mechanical strength and thermal conductivity are highly sensitive to the water demand of the biomass. Direct partial substitution of EPS by cup plant appears feasible and could be a part of the decarbonization of the construction sector.

Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian–Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-)sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the observed signal of carbon isotope variability. These findings put constraints on the application of Permian–Triassic carbon isotope chemostratigraphy based on whole-rock samples, which appears less refined than classical biozonation dating schemes. On the other hand, this signal of increased carbon isotope variability concurrent with the largest mass extinction of the Phanerozoic may provide information about local carbon cycling mediated by spatially heterogeneous (sub-)sea-floor microbial communities under suppressed bioturbation.

We present a proof of principle method to reconstruct nuclear magnetic resonance spectra after perturbing the spin system with a series of Rabi modulated continuous wave excitations. This continuous wave method provides an exciting alternative to pulsed Fourier transform methods which dominate magnetic resonance techniques. Applications include the measurement of ultra-short relaxation samples, which would be beneficial for sodium imaging or the assessment of bone and connective tissues. It is known that under Rabi modulated continuous wave excitation the spin system will reach a substantial periodic orbit. In a first experiment, we confirm that these periodic orbits are affected by off-resonance effects, and therefore encode chemical shift information. Spectroscopy is posed as an inverse problem in a second experiment and we apply a nonlinear estimation model to obtain nuclear magnetic resonance spectra from experimental measurements. Refereed/Peer-reviewed

Employing the oxygen reduction reaction (ORR) exemplarily, the suitability of the hanging meniscus RDE (HMRDE) technique for viscous electrolytes—in particular for ionic liquids—was examined. RDE and HMRDE experiments were carried out using polycrystalline Pt disks in contact with either concentrated phosphoric acid, N,N-diethylmethylammoniumtriflate ([Dema][TfO]) or 2-sulfoethylmethyl-ammoniumtriflate ([2-Sema][TfO]). RDE measurements revealed Levich factors of the oxygen transport close to the theoretical value, even if the thickness of the hydrodynamic layer was about ⅔ of the disk diameter. HMRDE experiments showed a pronounced scattering of the Levich factors, which means a significant error in the determination of the mass transport parameters. In contrast, reliable Tafel factors of ORR were obtained from HMRDE experiments with viscous mixtures of [2-Sema][TfO] and water. The thickness of the perturbed layer δ pl near the edge of the HMRDE was found to be virtually independent of the viscosity of the respective electrolyte. In the case of viscous electrolytes like ionic liquids, the HMRDE technique is particularly suitable for investigating the kinetic parameters of electrochemical processes at elevated temperatures >100 °C, whereas a more precise determination of mass transport properties will only be possible once the experimental error can be significantly reduced.

A new framework for B

Stereotactic ablative body radiotherapy (SABR) is demonstrating good local control for patients with inoperable primary renal cell carcinoma. In a previous pilot study we identified magnetic resonance imaging (MRI) early response biomarkers that correlate with later morphological changes in computed tomography (CT) images. These early functional changes in diffusion and perfusion following radiotherapy were observed on MRI and have the potential to identify non-responders who may benefit from adjuvant or salvage therapies. Here we detail the imaging protocol for an MRI sub-study of the Focal Ablative STereotactic Radiosurgery for Cancers of the Kidney (FASTRACK II) trial. A preliminary patient case demonstrates the high quality of the imaging data, with discussion of the improvements made from the pilot protocol for improved motion management and correction. We aim to validate the previously identified early response MRI biomarkers with this rich prospective multi-centre dataset.

Objective: The aim is to demonstrate dynamic in-vivo tracking of CAR T cell therapy for treatment of solid tumors using Cu-64 labeled superparamagnetic iron oxide nanoparticles (SPION) as novel dual PET-MR imaging agent. Methodology: Cu-64 SPION: Cu-64 radioisotope is bound to silica coated SPION using enhanced electrolysis plating techniques with tin and palladium seeding. Preclinical Model: Mouse splenic T cells were activated with anti-CD3, anti-CD28 & cultured with IL-2 and IL-7, prior to being transduced with second generation anti-Her-2 CAR (scFv-CD28-CD3ζ). 5 x 105 E0771-hHER2 breast tumor cells were implanted subcutaneously into male C57Bl/6-human HER2 transgenic mice. 107 labeled CAR T or control T cells (Cu-64 5-8 MBq) were injected into tail vein. Clinical Model: Activated T cells using antibody CD3 (OKT3) & IL-2 are transduced with retroviral vector constructs encoding for chimeric T-cell receptor specific for Lewis Y antigen. Modified T-cells are further expanded ex-vivo and reinfused. 3 x 108 CAR T cells were labeled with Cu-64 (200 - 300 MBq). Labeling of CAR T cells with Cu-64 SPION: Transfecting agent protamine sulphate facilitated cellular uptake of Cu-64 SPION within cells. Functional assays: 51Chromium release, cytometric bead array and cell viability showed that labeling process did not affect CAR T cell cytotoxicity, cytokine secretion (TNFα and IFN-γ) and viability. CAR T Cell Tracking: Scanning was performed using clinical grade dual PET-MR scanner. Preliminary Data: In this clinical trial (HREC/16/PMCC/30) patients are being enrolled for first in human in vivo study to determine how many cells distribute to solid tumor sites within first few days of CAR T cell therapy. This is first data that demonstrates that CAR-T cells can be consistently and efficiently labeled (≤60%) with cell viability (≥85%) and at sensitivity comparable to detecting at least z cells at tumor site using clinical grade dual PET-MR scanner. SUVmean values provides insight into individual response to therapy. The observed increase in SUVmax over time specifies localization of CAR T cells at tumor sites. Clinical data at early time point showed moderate uptake in lungs posterior basal segments without increased activity over next few days, thus suggesting transient process. Mild, diffuse bone marrow and relatively intense uptake in the liver and spleen suggests margination of cells to the reticulo-endothelial system. Distinct PET signal suggests localization of labeled cells in the secondary tumor sites. Little background uptake in important organs such as brain and heart indicate the safety profile of imaging agent. Absence of signal in bladder indicates hepatobiliary excretion, which may allow re-absorption from GI tract and re-circulation. Distinct PET signal within tumor in preclinical studies confirms trafficking of CAR T cells to tumor site as compared to controls. A negative contrast in the liver on T2 weighted MRI in both the preclinical and clinical studies. Preliminary Conclusion:This is first in human in vivo study to show CAR T cell distribution in real time and provides insight into individual responses of tumors to therapy. CAR T cell functionality largely remain unchanged due to labeling process. The preliminary findings indicate that labeled cells traffic to tumor sites in first few hours of infusion and remain persistent for extended period. Citation Format: Ritu Singla, Dominic Wall, Samuel Anderson, Nicholas Zia, James C. Korte, Lucy Kravets, Gerard McKiernan, Jeanne Butler, Amanda Gammilonghi, Jyoti Arora, Ben Solomon, Rodney Hicks, Timothy Cain, Phillip Darcy, Carleen Cullinane, Paul Neeson, Rajesh Ramanathan, Ravi Shukla, Vipul Bansal, Simon Harrison. Dynamic real time in vivo CAR T cell tracking: Clinical and preclinical studies using a novel dual PET-MR imaging agent [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-023.

3557 Background: This is a first in human in-vivo biodistribution of ex-vivo labelled CAR T cells assessed in a cohort of patients. Cells were labelled with novel Cu-64 labelled superparamagnetic iron oxide nanoparticles (SPION) and infused IV into patients with solid tumors & tracked using clinical dual PET-MR. The study validates the clinical translation of CAR T cell in-vivo tracking in real time. Methods: Cu-64 radioisotope was bound to silica coated SPION using electrolysis plating with tin & palladium seeding. Cellular uptake of Cu-64 SPION was facilitated with a transfecting agent. Functional assays including 51Chromium release, cytometric bead array demonstrated that labelling process did not affect cytotoxicity & cytokine secretion (TNFα & IFN-g). T cells were transduced with retroviral vector constructs encoding for second-generation chimeric T-cell receptor specific for carbohydrate Lewis Y antigen. Modified T-cells were expanded ex-vivo & were labelled with Cu-64 (~300 MBq) prior to re-infusion (3 x108 labelled cells). Scanning is performed with Siemens 3T dual PET-MR scanner. Results: In this first in human in-vivo study (HREC/16/PMCC/30) a cohort of patients received ex-vivo labelled CAR T cells to determine how many labelled cells distribute to solid tumor sites within 3-5 days. Our results demonstrate that cells can be efficiently labelled (≤60%) with high cell viability (≥85%) at a sensitivity sufficient to detect labelled cells at tumor site for up to 5 days. An observed trend in SUVmean & SUVmax provided insight into efficacy & individual response to therapy. Early time points showed moderate uptake of labelled cells in lungs posterior basal segments without increased activity over next few days, suggesting a transient process. Mild, diffuse bone marrow & relatively intense uptake of labelled cells in liver & spleen suggests margination of cells to reticulo-endothelial system. Distinct PET signal at some of the tumor sites at 24 h suggests antigen specific localization & time taken to reach these sites. Excretion via hepatobiliary indicated reabsorption from GI tract & re-circulation of labelled cells. Minimal uptake in brain & heart supported safety profile of labeling agent. Conclusions: This is first in human in-vivo study to provide highly valuable visual and dynamic data in real time and provides insight into individual responses to therapy. CAR T cell functionality largely remain unchanged due to labeling process. The findings indicate that labelled cells traffic to tumor sites at later time points & remain persistent for extended period of time.

Background & Aim This is a first in human in-vivo biodistribution of ex-vivo labelled CAR T cells assessed in a cohort of patients. Cells were labelled with novel Cu-64 labelled superparamagnetic iron oxide nanoparticles (SPION) and infused IV into patients with solid tumors & tracked using clinical dual PET-MR. The study validates the clinical translation of CAR T cell in-vivo tracking in real time. Methods, Results & Conclusion Methods Cu-64 radioisotope was bound to silica coated SPION using electrolysis plating with tin & palladium seeding. Cellular uptake of Cu-64 SPION was facilitated with a transfecting agent. Functional assays including 51Chromium release, cytometric bead array demonstrated that labelling process did not affect cytotoxicity & cytokine secretion (TNFα & IFN-g). T cells were transduced with retroviral vector constructs encoding for second-generation chimeric T-cell receptor specific for carbohydrate Lewis Y antigen. Modified T-cells were expanded ex-vivo & were labelled with Cu-64 (∼300 MBq) prior to re-infusion (3 × 108 labelled cells). Scanning is performed with Siemens 3T dual PET-MR scanner. Results In this first in human in-vivo study (HREC/16/PMCC/30) a cohort of patients received ex-vivo labelled CAR T cells to determine how many labelled cells distribute to various body organs and lesions within first 3-5 days. Our results demonstrate that both fresh (N =3) and thawed cells (N =3) can be efficiently labelled in the range of 40% - 80% with high cell viability (≥90%). An observed trend in SUVmean provided insight into efficacy & individual response to therapy. Early time points showed moderate uptake of labelled cells in lungs posterior basal segments without increased activity over next few days, suggesting a transient process. Mild, diffuse bone marrow & relatively intense uptake of labelled cells in liver & spleen suggests margination of cells to reticulo-endothelial system. Excretion via hepatobiliary indicated reabsorption from GI tract & re-circulation of labelled cells. The initial data shows that labelled cell may remain with in the system for upto 10-15 days. Minimal uptake in brain & heart supported safety profile of labeling agent. Conclusions This is first in human in-vivo study to provide highly valuable visual and dynamic data in real time and provides insight into individual responses to therapy. CAR T cell functionality largely remain unchanged due to labeling process. The findings indicate that labelled cells remain persistent for extended period of time.

Knowledge of habitat use by animals within urban-riparian corridors during the breeding season is important for conservation, yet remains understudied. We examined the bird community along an urban-riparian corridor through metropolitan Boise, Idaho and predicted that occupancy of individual species and species richness would be greater in forested areas than in urbanized areas. We surveyed birds throughout the summers of 2009 and 2010 and quantified the m2 of each cover-type within 50-m, 100-m, and 200-m buffers surrounding each survey location using satellite imagery. Occupancy modeling revealed that eight of 14 species analyzed were positively associated with riparian forest, and no species avoided forest. Species richness was negatively associated with the amount of paved surface within 100 m of a survey site with richness declining by more than two species for every hectare of paved surface. Most associations with cover-types–especially riparian forest–were at ⩾100 m. Therefore, the riparian forest within 100 m of a given site along an urban-riparian corridor should be the most important for maintaining species richness.

Objectives The American Board of Emergency Medicine (ABEM) Maintenance of Certification (MOC) program requires every ABEM-certified physician to attest to participating in a quality improvement (QI) activity every 5 years. Understanding the type and frequency of these QI activities could inform the emergency medicine community about the variety of QI activities in which emergency physicians (EPs) are involved. These QI activities could provide ideas for the development of additional quality measures. Methods This was a retrospective descriptive study of self-reported QI activity attestations from the ABEM MOC program during 2013. Attestations were provided by ABEM-certified EPs using the ABEM MOC website. The type, number, and cumulative frequency of activities are reported. Results ABEM received 9,380 attestations for QI activities in 91 different categories. The three most commonly reported activities were acute myocardial infarction-percutaneous coronary intervention within 90 minutes of arrival (includes door-to-balloon time), door-to-doctor times, and throughput time measures. These three activities comprised 36.4% of attestations. More than half (54.4%) of the attestations were captured by the five most frequently attested activities, 67.1% by the top seven categories, and 89.9% by the top 21 categories. Of these 21 categories, 10 involved clinical protocols, nine were time-centered measures, and two were patient-centered activities. Conclusions This report demonstrates that diverse QI activities occur in emergency departments (EDs) across the United States. The majority of reported projects are nested in a few categories, following recognized areas of emphasis in emergency care, particularly in areas using time-sensitive metrics.

Objectives The initial step in certification by the American Board of Emergency Medicine (ABEM) requires passing a multiple-choice-question qualifying examination. The qualifying examination is typically taken in the first year after residency training. This study was undertaken to determine if a delay in taking the qualifying examination is associated with poorer performance. The authors also examined the relationship between in-training examination scores and qualifying examination scores. Methods This was a pooled time-series cross-section study. Primary measurements were initial qualifying examination scores, the timing of the qualifying examination, and in-training examination scores. The three groups, based on qualifying examination timing, were immediate, 1-year delay, and ≥2-year delay. In-training examination scores were analyzed to determine the relationship between intrinsic ability, examination timing, and qualifying examination scores. For analysis, a generic pooled ordinary least-squares dummy variable model with robust standard errors was used. A pre hoc level of significance was determined to be α < 0.01. Results There were 16,353 qualifying examination test administrations between 2000 and 2012. In-training examination scores were positively correlated with qualifying examination scores (p < 0.001). The group pass rates were 98.9% immediate, 95.6% 1-year delay, and 86.6% ≥2-year delay. After controlling for in-training examination scores, delay taking the qualifying examination of 1 year was associated with a decrease in score of –0.6 (p = 0.003). A delay in taking the qualifying examination ≥2 years was associated with a decrease in score of –2.5 points (p < 0.001). Conclusions After accounting for innate ability using in-training examination scores, delay taking the qualifying examination was associated with poorer performance. This effect was more pronounced if the delay was ≥2 years. Resumen Objetivos El paso inicial en la certificacion por la American Board of Emergency Medicine (ABEM) requiere aprobar un examen de cualificacion (EC) de preguntas de eleccion multiple. El EC se realiza habitualmente en el primer ano tras la formacion de la residencia. Este estudio se llevo a cabo para determinar si un retraso en la realizacion del EC esta asociado con un peor rendimiento. Tambien se examino la relacion entre las puntuaciones del examen durante la formacion (EDF) y las puntuaciones del EC. Metodologia Estudio transversal de series temporales sumatorias. Las mediciones principales fueron las puntuaciones iniciales del EC, el momento del EC y las puntuaciones del EDF. Los tres grupos, basados en el momento del EC fueron: inmediato, un ano de retraso y 2 o mas anos de retraso. Se analizaron las puntuaciones del EDF para determinar la relacion entre la capacidad intrinseca, el tiempo del examen y las puntuaciones del EC. Para el analisis, se utilizo un modelo variable de minimos cuadrados ordinarios sumatorio generico con errores estandar robustos. Se determino un nivel de significacion pre hoc de α < 0,01. Resultados Hubo 16.353 EC entre el 2000 y el 2012. Las puntuaciones del EDF se correlacionaron positivamente con las puntuaciones del EC (p < 0,001). La proporcion de aprobados de cada grupo fue: 98,9% para el grupo inmediato, 95,6% para 1 ano de retraso y 86,6% para 2 o mas anos de retraso. Tras ajustar por las puntuaciones de EDF, el retraso del EC un ano se asocio con un descenso en la puntuacion de -0,6 (p = 0,003). Un retraso de realizacion del EC de 2 o mas anos se asocio con descenso en la puntacion de -2,5 puntos (p < 0,001). Conclusiones Tras tener en cuenta las capacidades innatas mediante las puntuaciones del EDF, el retrasar la realizacion del EC se asocio con un peor rendimiento. Este efecto fue mas pronunciado si el retraso fue ≥ a 2 anos.

The American Board of Emergency Medicine gathers extensive background information on emergency medicine residency programs and the residents in them. We present the 2014 annual report on the status of US emergency medicine training programs.

Objectives The Accreditation Council for Graduate Medical Education (ACGME) and the American Board of Medical Specialties sought to define milestones for skill and knowledge acquisition during residency training. Milestones are significant objective observable events. The milestones are listed within a structure that is derived from the ACGME general competencies. Major groups of milestones are called “subcompetencies.” The original 24 subcompetencies containing 255 milestones for emergency medicine (EM) were developed through a multiorganizational group representing most EM stakeholder groups. To assure that the milestones reflected EM resident progress throughout training, the EM Milestones Working Group (EM MWG) sought to validate the individual milestones. Methods A computer-based survey was sent to all EM residency programs. The survey period began on April 30, 2012, and concluded on May 15, 2012. Respondents were asked to assign each milestone to a specific level of skill or knowledge acquisition. These levels ranged from a beginning resident to an accomplished clinician. There were two different forms that divided the milestones into two groups of 12 subcompetencies each. Surveys were randomly assigned to programs. Results There were five respondents (the program director and four key faculty) requested from each of the 159 residences. There were responses from 96 programs (60.4%). Of the 795 survey recipients, 28 were excluded due to prior exposure to the EM milestones. Of the remaining 767 potential respondents, 281 completed the survey (36.6%) within a 16-day period. Based on the survey results, the working group adjusted the milestones in the following ways: one entire subcompetency (teaching) was eliminated, six new milestones were created, 34 milestones were eliminated, 26 milestones were reassigned to a lower level score, and 20 were reassigned to a higher level. Nineteen milestones were edited to provide greater clarity. The final result was 227 discrete milestones among 23 subcompetencies. Conclusions The EM milestones were validated through a milestone assignment process using a computer-based survey completed by program directors and key faculty. Milestones were revised in accordance with the results to better align assignment within each performance level. Resumen Los Objetivos por Areas de la Medicina de Urgencias y Emergencias: Un Estudio de Validacion Objetivos El Accreditation Council for Graduate Medical Education (ACGME) y la American Board of Medical Specialties buscaron definir los objetivos por areas para la adquisicion de las habilidades y el conocimiento durante la formacion de la residencia. Los objetivos por areas son hechos observables objetivos y significativos. Los objetivos por areas se enumeran en una estructura que se deriva de las competencias generales del ACGME. Los grupos mayores de los objetivos por areas se denominan subcompetencias. Las 24 subcompetencias originales que contienen 255 objetivos por areas para la medicina de urgencias y emergencias (MUE) se desarrollaron a traves de un grupo de varias organizaciones que representan a la mayoria de los grupos interesados en la MUE. Para asegurar que los objetivos por areas reflejaron el progreso del residente de MUE mediante la formacion, el grupo de trabajo de los objetivos por areas de la MUE busco validar individualmente estos objetivos. Metodologia Se envio una encuesta electronica a todos los programas de residencia de MUE. El periodo de la encuesta comenzo el 30 de abril de 2012 y concluyo el 15 de mayo de 2012. Se solicito a los respondedores que asignaran a cada uno de los objetivos por areas un nivel especifico de adquisicion de habilidades o conocimiento. Estos niveles variaron desde el residente a su inicio hasta un clinico consumado. Hubo dos formularios diferentes que dividieron los objetivos por areas en dos grupos de 12 subcompetencias cada uno. Las encuestas se asignaron de forma aleatoria a los programas. Resultados Se seleccionaron cinco respondedores (el director de programa y cuatro profesores representativos de la facultad) para cada una de los 159 programas de residencia. Hubo respuestas de 96 programas (60,4%). De las 795 encuestas recibidas, 28 se excluyeron debido a la experiencia previa en los objetivos por areas de la MUE. De los restantes, 767 respondedores potenciales, 281 completaron la encuesta (36,6%) en un periodo de 16 dias. En base a los resultados de la encuesta, el grupo de trabajo ajusto los objetivos por areas de la siguiente manera: se elimino una subcompetencia integra (ensenanza), se crearon 6 nuevos objetivos por areas, se eliminaron 34 objetivos por areas, se reasignaron 26 objetivos por areas a un nivel menor y 20 a un nivel mayor. Se corrigieron 19 objetivos por areas para proporcionar una mayor claridad. El resultado final fueron 227 objetivos por areas distintos en 23 subcompetencias. Conclusiones Los objetivos por areas de la MUE se validaron a traves de un proceso de asignacion de objetivos por areas mediante una encuesta electronica completada por los directores de los programas y profesores representativos de la facultad. Los objetivos por areas se revisaron de acuerdo a los resultados para una mejor alineacion de las asignaciones en cada nivel de realizacion.

Background The Model of the Clinical Practice of Emergency Medicine is the basis for the content specifications of all American Board of Emergency Medicine (ABEM) examinations. This study describes the frequency with which ABEM diplomates diagnose and manage the conditions and components listed in the Model of the Clinical Practice of Emergency Medicine. Objectives The objectives of this study were to determine the frequency with which ABEM diplomates diagnose and manage the conditions and components described in the Model of the Clinical Practice of Emergency Medicine. Methods The listing of conditions and components of the Model of the Clinical Practice of Emergency Medicine were sent to 16,230 randomly selected ABEM diplomates. One of five surveys was sent to each diplomate. Each condition and component was assessed by participants for the frequency that emergency physicians diagnose (D) and manage (M) that condition, as seen in their practice of Emergency Medicine. Results Of the 16,230 surveys sent, 5006 were returned (30.8% response rate). The genders of the respondents were 75% male and 24% female. The ages of the respondents were primarily in the age 40–49 years, and 30–39 years age groups. All categories of the listing of conditions and components of the Model of the Clinical Practice of Emergency Medicine were encountered frequently in the practice of Emergency Medicine, as indicated by study participants. Conclusions A survey of practicing ABEM diplomates was useful in defining the frequency with which specific conditions and components are diagnosed and managed in the practice of Emergency Medicine.

The American Board of Emergency Medicine (ABEM) gathers extensive background information on emergency medicine residency programs and the residents in those programs. We present the 2013 annual report on the status of US emergency medicine training programs.

Subduralhämatome (SDH) sind mit einer erhöhten Morbidität und Mortalität vergesellschaftet und treten in der Regel als chronische SDH bei älteren Patienten auf. Die häufigsten Zeichen und Symptome eines chronischen SDH – Kopfschmerzen, Vigilanzänderungen, Gangunsicherheit und Hemiparese – kommen auch bei anderen Krankheitsbildern vor, was in der Differentialdiagnose berücksichtigt werden muss. Bei symptomatischen Patienten mit fokalen neurologischen Ausfällen sollte eine chirurgische Intervention in Erwägung gezogen werden, während bei asymptomatischen Patienten oder solchen, die lediglich an Kopfschmerzen leiden, auch eine konservative Behandlung mit klinisch-radiologischer Nachkontrolle in Frage kommt. Auch nach chirurgischer Intervention kommt es leider in 5–33% zu einem Rezidiv des chronischen SDH, weshalb Patienten mit einem chronischen SDH, ungeachtet der Indikation für eine orale Antikoagulation, eine Herausforderung für die behandelnden Ärzte darstellen.

To date, there appear to be no studies investigating the practice settings of all Medical Toxicology (MT) diplomates. The MT Assessment of Practice Performance Taskforce queried all MT diplomates about their current practice settings relative to the number of patients seen, the most common diagnoses, and the percent of time spent in their roles as medical toxicologists (MTs) and in their primary specialty. One hundred twenty-seven surveys were completed (44% response rate). Seventy-nine percent of respondents were affiliated with poison centers. Eighty-eight percent of participants were clinically active and reported seeing or consulting on behalf of at least ten patients over a 2-year period. Acetaminophen toxicity was the most common diagnosis encountered by respondents. Other common diagnoses included antidepressant toxicity, antipsychotic toxicity, mental status alteration, metal/environmental toxicity, envenomation, and pesticide toxicity. While respondents were likely to spend more time in direct patient care in their primary specialty, compared to consulting on behalf of patients, they were more likely to consult on behalf of patients in their role as MTs. Respondents spent more time in research, education, and population health in their role as an MT than in their primary specialty. Administrative activities were more commonly reported in association with the respondents' primary specialty than in their role as MTs. Most MTs encounter certain diagnoses with significant frequency and see a substantial number of patients within these categories. The majority spends more time on direct patient care in their primary specialty but is actively engaged in MT education, research, population health, and administration. A longitudinal assessment of MT practice patterns could inform MT curricular development and practice performance evaluation.

To date, there appear to be no studies that assess Medical Toxicologists’ (MTs) practice improvement (PI) activities in their Medical Toxicology practice settings. The MT Assessment of Practice Performance (APP) Taskforce queried all MT diplomates about (1) activities currently available in their practice settings that potentially would meet the requirements of APP, (2) potential APP activities that best fit with current MT practice, and (3) the relationship between MT practice patterns and APP requirements. One hundred twenty-seven surveys were completed. Participation in MT practice improvement activities is not universal, with approximately a third of the survey participants reporting that they are not involved in any practice improvement activity. Few respondents reported that they collected performance improvement-related data. Most who did so participated in CME, case, or chart reviews. Peer reviews, self-improvement plans based on chart reviews, and population research were considered the most valid measures of MT practice improvement. Communication skills were considered important topics for patient surveys. Suggested outcomes for peer assessment included accuracy of information provided, understanding medical staff concerns, timeliness of feedback, and helpfulness. Most respondents rated all of the APP options as being somewhat very intrusive. Access to those with sufficient knowledge of the diplomate’s practice improvement program to verify APP could pose a challenge to a successful completion of APP requirements. Optimal settings for the APP program administration are hospitals and poison centers. While barriers to MT APP activities exist, studying current MT diplomates’ opinions and practices could inform the future development and administration of such programs.

Zusammenfassung 4 freiwillige Versuchspersonen tranken je 100 g Backhefe, die fast rein aus Candida robusta (imperfekte Form von Saccharomyces cerevisiae) bestand. In 2 Fallen wurde die Magensaure vorher mit Natron abgestumpft. Im Abstand von 3 bis 36 Std danach liesen sich keine Hefen im Blut oder Urin nachweisen.

The American Board of Emergency Medicine gathers extensive background information on emergency medicine residents and the programs in which they train. We present the sixth annual report on the status of US emergency medicine residency programs. [ Ann Emerg Med. 2003;41:714-732.]

Objectives The Accreditation Council for Graduate Medical Education (ACGME) Milestones describe behavioral markers for the progressive acquisition of competencies during residency. As a key component of the Next Accreditation System, all residents are evaluated for the acquisition of specialty-specific Milestones. The objective was to determine the validity and reliability of the emergency medicine (EM) Milestones. Methods The ACGME and the American Board of Emergency Medicine performed this single-event observational study. The data included the initial EM Milestones performance ratings of all categorical EM residents submitted to the ACGME from October 31, 2013, to January 6, 2014. Mean performance ratings were determined for all 23 subcompetencies for every year of residency training. The internal consistency (reliability) of the Milestones was determined using a standardized Cronbach's alpha coefficient. Exploratory factor analysis was conducted to determine how the subcompetencies were interrelated. Results EM Milestone performance ratings were obtained on 100% of EM residents (n = 5,805) from 162 residency programs. The mean performance ratings of the aggregate and individual subcompetency scores showed discrimination between residency years, and the factor structure further supported the validity of the EM Milestones. The reliability was α = 0.96 within each year of training. Conclusions The EM Milestones demonstrated validity and reliability as an assessment instrument for competency acquisition. EM residents can be assured that this evaluation process has demonstrated validity and reliability; faculty can be confident that the Milestones are psychometrically sound; and stakeholders can know that the Milestones are a nationally standardized, objective measure of specialty-specific competency acquisition.

The spectrin membrane skeleton is a ubiquitous cytoskeletal structure with several cellular roles, including the maintenance of cell integrity, determination of cell shape and as a contributor to cell polarity. We have isolated mutations in the gene encoding βHeavy-spectrin in Drosophila, and have named this essential locus karst. karst mutant individuals have a pleiotropic phenotype characterized by extensive larval lethality and, in adult escapers, rough eyes, bent wings, tracheal defects and infertility. Within karst mutant eyes, a significant number of ommatidia specifically lack photoreceptor R7 alongside more complex morphological defects. Immunolocalization of βHeavy-spectrin in wild-type eye-antennal and wing imaginal discs reveals that βHeavy-spectrin is present in a restricted subdomain of the membrane skeleton that colocalizes with DE-cadherin. We propose a model where normal levels of Sevenless signaling are dependent on tight cell-cell adhesion facilitated by the βHeavy-spectrin membrane skeleton. Immunolocalization of βHeavy-spectrin in the adult and larval midgut indicates that it is a terminal web protein, but we see no gross morphological defects in the adult apical brush border in karst mutant flies. Rhodamine phalloidin staining of karst mutant ovaries similarly reveals no conspicuous defect in the actin cytoskeleton or cellular morphology in egg chambers. This is in contrast to mutations in α-spectrin, the molecular partner of βHeavy-spectrin, which affect cellular structure in both the larval gut and adult ovaries. Our results emphasize the fundamental contribution of the spectrin membrane skeleton to normal development and reveals a critical interplay between the integrity of a cell’s membrane skeleton, the structure of cell-cell contacts and cell signaling.

Many structural, signaling, and adhesion molecules contain tandemly repeated amino acid motifs. The alpha-actinin/spectrin/dystrophin superfamily of F-actin-crosslinking proteins contains an array of triple alpha-helical motifs (spectrin repeats). We present here the complete sequence of the novel beta-spectrin isoform beta(Heavy)-spectrin (beta H). The sequence of beta H supports the origin of alpha- and beta-spectrins from a common ancestor, and we present a novel model for the origin of the spectrins from a homodimeric actin-crosslinking precursor. The pattern of similarity between the spectrin repeat units indicates that they have evolved by a series of nested, nonuniform duplications. Furthermore, the spectrins and dystrophins clearly have common ancestry, yet the repeat unit is of a different length in each family. Together, these observations suggest a dynamic period of increase in repeat number accompanied by homogenization within each array by concerted evolution. However, today, there is greater similarity of homologous repeats between species than there is across repeats within species, suggesting that concerted evolution ceased some time before the arthropod/vertebrate split. We propose a two-phase model for the evolution of the spectrin repeat arrays in which an initial phase of concerted evolution is subsequently retarded as each new protein becomes constrained to a specific length and the repeats diverge at the DNA level. This evolutionary model has general applicability to the origins of the many other proteins that have tandemly repeated motifs.

The ionic and electronic partial thermopowers and the Soret effect of α-Ag2 + δS (low temperature phase) have been studied as functions of temperature and deviation from stoichiometry δ by means of a nonisothermal galvanic cell. From a combination of these data with results from additional measurements of the partial entropy of silver metal in α-Ag2 + δS, the heat of transport of silver metal is determined. The measured transport properties are discussed in respect to the defect structure and isothermal transport properties of α-Ag2 + δS and information on the individual heats of transport of the mobile point defects is extracted. We observe a strong composition dependence of QAg∗ which can be explained within our formal analysis. The electronic properties can be interpreted within the model of a non-degenerate electron gas. The scattering factor of electronic defects in the statistical description of thermopower is equivalent to the electronic heat of transport in the phenomenological description.

Nach einer Ubersicht uber wichtlge Einflusse auf die feuchtebedingten Langenanderungen von Holzwerkstoffen (Plattenstruktur und-komponenten, Mesmethode, Probengrose, Klimatisierung) wird uber Messungen mit kunstharz-und mineralisch gebundenen Spanplatten, im Nas-und Trockenverfahren hergestellten Faserplatten, OSB, Massivholzplatte und Furniersperrholz berichtet. Der Klimasprung vom Normalklima 20 °C/65% rel. Luftfeuchte in das Trockenklima 20/35 bzw. Feuchtklima 20/85 wird mit einer zweistufigen Klimatisierung verglichen. Die gemessenen Langenanderungen der Holzwerkstoffe sowie die Ausgleichsfeuchten bei 20 °C fur die relativen Luftfeuchten 35, 50, 65, 75 und 85% sind tabelliert. Die Ergebnisse erlauben wichtige Schlusfolgerungen fur die Neubearbeitung der EN 318, verdeutlichen den Einflus der Klimatisierungsart und zeigen die Moglichkeit eines Kurzverfahrens zur Qualitatsuberwachung an Holzwerkstoffen.

Objectives The American Board of Emergency Medicine (ABEM) Maintenance of Certification (MOC) program is a four-step process that includes the Continuous Certification (ConCert) examination. The ConCert examination is a validated, summative examination that assesses medical knowledge and clinical reasoning. ABEM began administering the ConCert examination in 1989. The ConCert examination must be passed at least every 10 years to maintain certification. This study was undertaken to determine longitudinal physician performance on the ConCert examination. Methods In this longitudinal review, ConCert examination performance was compared among residency-trained emergency physicians (EPs) over multiple examination cycles. Longitudinal analysis was performed using a growth curve model for unbalanced data to determine the growth trajectories of EP performance over time to see if medical knowledge changed. Using initial certification qualifying examination scores, the longitudinal analysis corrected for intrinsic variances in physician ability. Results There were 15,085 first-time testing episodes from 1989 to 2012 involving three examination cycles. The mean adjusted examination scores for all physicians taking the ConCert examination for a first cycle was 85.9 (95% confidence interval [CI] = 85.8 to 85.9), the second cycle mean score was 86.2 (95% CI = 86.0 to 86.3), and the third cycle was 85.4 (95% CI = 85.0 to 85.8). Using the first examination cycle as a reference score, the growth curve model analysis resulted in a coefficient of +0.3 for the second cycle (p < 0.001) and –0.5 for the third cycle (p = 0.02). Initial qualifying (written) examination scores were significant predictors for ConCert examination scores. Conclusions Over time, EP performance on the ConCert examination was maintained. These results suggest that EPs maintain medical knowledge over the course of their careers as measured by a validated, summative medical knowledge assessment. Resumen Objetivos El programa de mantenimiento de certificacion (MC) de la American Board of Emergency Medicine (ABEM) es un proceso de cuatro pasos que incluye el examen de certificacion continuada (continuous certification, ConCert). El ConCert es un examen sumatorio y validado que valora el conocimiento y el razonamiento clinico medico. La ABEM comenzo a realizar el examen ConCert en 1989. El ConCert debe ser aprobado al menos cada diez anos para mantener la certificacion. Este estudio se llevo a cabo para determinar el rendimiento del medico en el examen ConCert a lo largo del tiempo. Metodologia En esta revision longitudinal, el rendimiento del examen ConCert se comparo entre los medicos de urgencias y emergencias (MUE) formados en el programa de residencia a lo largo de multiples periodos de examen. Se realizo un analisis longitudinal mediante un modelo de curva de crecimiento (MCC) para datos no balanceados para determinar las trayectorias de crecimiento del rendimiento del MUE a lo largo del tiempo para ver si el conocimiento medico habia cambiado. Con las puntuaciones iniciales del examen ConCert, el analisis longitudinal se ajusto por las varianzas intrinsecas en la habilidad del medico. Resultados Hubo 15.085 episodios de examenes por primera vez desde 1989 a 2012, que incluian tres ciclos de examen. La media ajustada de las puntuaciones del examen para todos los medicos que realizaron el examen ConCert para un primer ciclo fue 85,9 (IC 95% = 85,8 a 85,9); la media de puntuacion del segundo ciclo fue de 86,2 (IC 95% = 86,0 a 86,3); y la del tercer ciclo fue de 85,4 (IC 95% = 85,0 a 85,8). Usando el primer ciclo de examen como referencia de puntuacion, el analisis de los MCC resulto en un coeficiente de +0.3 para el segundo ciclo (p

Experiments on thermal demixing of β-Ag 2+δ S (high-temperature phase) are reported. By means of a nonisothermal solid state galvanic cell, the redistribution of the metal excess δ in an external temperature gradient has been investigated in the temperature range 200°C < T

The experimental determination of the (reduced) heat of transport of silver, Q* Ag , in β-Ag 2+δ S by the direct measurement of the silver flux in a given temperature gradient, under the condition of equal composition at the ends of the crystalline sample, is reported. The measurement is based on the application of galvanic cells for the simultaneous control and measurement of both the silver flux and composition. A set of data for the heat of transport of silver is determined for 210°C < T < 270°C and 0.96.10 -3 < δ < 1.7.10 -3 . The measured values for the heat of transport, Q* Ag , are positive and nearly independent of the composition of β-Ag 2+δ S. Thus, a flux of silver metal which is induced by a temperature gradient is directed towards the low temperature side of the crystal. In addition, a strong temperature dependence of Q* Ag was observed.

Background The Lifelong Learning and Self-assessment (LLSA) component of the American Board of Emergency Medicine (ABEM) Maintenance of Certification (MOC) program is a self-assessment exercise for physicians. Beginning in 2011, an optional continuing medical education (CME) activity was added. Objectives As a part of a CME activity option for the LLSA, a survey was used to determine the relevancy of the LLSA readings and the degree to which medical knowledge garnered by the LLSA activity would modify clinical care. Methods Survey results from the 2011 LLSA CME activity were reviewed. This survey was composed of seven items, including questions about the relevancy of the readings and the impact on the physician's clinical practice. The questions used a 5-point Likert scale and data underwent descriptive analyses. Results There were 2841 physicians who took the LLSA test during the study period, of whom 1354 (47.7%) opted to participate in the 2011 LLSA CME activity. All participants completed surveys. The LLSA readings were reported to be relevant to the overall clinical practice of Emergency Medicine (69.6% strongly relevant, 28.1% some relevance, and 2.3% little or no relevance), and provided information that would likely help them change their clinical practices (high likelihood 38.8%, some likelihood 53.0%, little or no change 8.2%). Conclusions The LLSA component of the ABEM MOC program is relevant to the clinical practice of Emergency Medicine. Through this program, physicians gain new knowledge about the practice of Emergency Medicine, some of which is reported to change physicians' clinical practices.

The American Board of Emergency Medicine (ABEM) gathers extensive background information on emergency medicine residency training programs and the residents in those programs. We present the 2012 annual report on the status of US emergency medicine training programs.

Vorbemerkung: Als ich mich 1977, im Alter von 47 Jahren in die Ausbildung zum TZI-Gruppenleiter begab, hatte ich das deutliche Gefuhl, ein solides Handwerk zu lernen. (Unter Fahigkeiten des TZI-Handwerks verstehe ich z.B. „Themen-Stellen“, Strukturen-Handhaben, „Prozess-Beobachten“). In diesem Sinn habe ich auch meine Arbeit mit Gruppen verstanden. Aber wenn ich dies meinen WILL-Freunden und Mitstreitern sagte, erntete ich Unverstandnis, wenn nicht gar entschiedene Ablehnung; als sei das Handwerkliche an TZI etwas Negatives. Das hat mich immer wieder ans Nachdenken gebracht. Hier das bisherige Resultat.

Wenn wir nach einer Wissenschaft suchen, die eine gemeinsame Erklarung fur all die vielen erschreckenden, beunruhigenden Vorgange in der Menschheit finden soll, fur Kriege, Massaker, Unfalle mit todlichen Folgen, Verwahrlosung, weit gestreute chronische Krankheiten..., die Liste kann gar nicht vollstandig ausfallen, dann musste es eine Wissenschaft sein, die sich kraft ihrer eigenen Definition mit kollektiven Zusammenhangen unter Menschen beschaftigt. Das ware die Soziologie. Aber wir, die Soziologen, schweigen oder teilen Unbedeutendes mit. Wir haben unsere Methoden und wir haben unsere Auftraggeber: beide fuhren uns wenigstens direkt nicht zur Erklarung solcher erschreckenden Phanomene. Wir erklaren eher, wie Zusammenhange funktionieren als wann sie nicht funktionieren. Zwar hat es in den Rivalitatskampfen zwischen Psychologie und Soziologie Tendenzen gegeben, fur alle moglichen individuellen Falle nach gesellschaftlichen Ursachen zu suchen; unter dem Stichwort Kapitalismuskritik meinte man den gemeinsamen Nenner fur Alkoholismus, Kriege, Verbrechen gefunden zu haben. (Viele Bande des „Kursbuch“ und der „Argumente“ sind gefullt mit solchen Erklarungsversuchen.) Aus anderen Lagern hat es immer wieder kritische Anklager gegeben, die entweder im Verlust von Religion oder im Vorherrschen technischen Denkens die Ursache fur so viel Elend gesehen haben. Fur einige Formen des Elends und der Katastrophe konnte beides zutreffen; andere sind auch durch Religionen nie beseitigt worden.

Einen wissenschaftlichen Text unterscheidet man auf den ersten Blick von einem nichtwissenschaftlichen durch die Feststellung, ob es Fusnoten, Verweise oder Zitate gibt. Das ist gewiss nicht das einzige Unterscheidungskriterium, aber ein bemerkens- und bedenkenswertes. Die zu untersuchende Fragen anhand dieses Befundes lauten: Was tut der Wissenschaftler, indem er so verfahrt? Was bedeutet es? Und was hat es fur Folgen?

Sind sich nicht alle in unserer Gesellschaft darin einig, dass es Fortschritt gibt und geben soll? Einerseits diejenigen im politischen Spektrum, fur die Geschichte ohne Fortschritt nicht denkbar ist, die „Progressiven“, die „Linken“ und auch die „Liberalen“, andererseits gehoren auch diejenigen dazu, die man als „Konservativ“ oder „Rechts“ einstuft. Denn wer sich aus deren Reihen nicht zum Fortschritt bekennen wurde, hatte bald an Ansehen oder Einfluss verloren. Gewiss, man hat durchaus unterschiedliche Vorstellung, worin denn der Fortschritt besteht: mehr Wohlstand, mehr personliche Freiheiten, mehr Gerechtigkeit, mehr Gesundheit, mehr Ordnung, mehr Technik, mehr Wissen. Und all diese „Mehr“ lassen sich ja schlecht auf einen Nenner bringen, sie widersprechen sich, schliesen sich zum Teil gegenseitig aus. Also setzt sich dann jede Gruppe oder Fraktion fur den Fortschritt ein, der ihren Ideen entspricht. Dabei konnte man es belassen. Am Ende gilt dann das Muster von Lessings Ringparabel: Abwarten, wem der Erfolg beschieden ist. Und die Zuschauer bzw. die Nachwelt konnten Wetten abschliesen, wem dieser Erfolg beschieden ist. Wenn wir uns aber nicht als Zuschauer verstehen, sondern selbst in der Arena stehen, ist es notwendig, etwas genauer zu fragen, was es mit dem Fortschritt auf sich hat.

In dreierlei Hinsicht Grenzen: Grenzen sind einfach da, sie fragen nicht nach Erlaubnis. Entscheidend sind die Reaktionen darauf, als Einzelner, als Gruppierung unterschiedlicher Auspragung. Und es hat fur alle Beteiligten Folgen, ob diese Reaktion Anteil nehmend gestaltet oder kriegerisch aggressiv gefuhrt wird. Wir alle machen Grenz-Erfahrungen, gewollte und ungewollte, tatsachliche und vorweggenommene, reale und phantasierte, solche, die in uns selbst liegen, solche, die wir am Gegenuber erfahren. Immer sind damit auch Gefuhle verbunden. Die meisten Beitrage in dieser Auswahl konnen auch unter dem Aspekt gelesen werden: ‚Wo verlauft fur mich darin die Grenze zwischen …?’, oder auch: ‚Wo wurde ich die Grenze ziehen?’ Zuletzt die Erinnerung an eine fur alle sichtbare Grenze: Konrad Thomas lebte lange Zeit unmittelbar an der innerdeutschen Grenze. Das war und hatte All-taglich und alltagliche, spurbare Auswirkungen. Und in einem der Texte dieses Buches nimmt er darauf direkten Bezug.

Objektivitat ist das Ziel aller unserer Erkenntnisbemuhungen. Was als objektiv gelten kann, ist unumstoslich und fordert Anerkennung. Im Alltag unserer Erfahrung brauchen wir dieses Attribut vielleicht gar nicht. Eine Wand ist eine Wand; und wer mit dem Kopf durch die Wand will, will Unmogliches. Aber nicht alles, was fur uns unumstoslich ist, hat die materielle Qualitat einer Wand. Wir wissen aus der Geschichte der Wissenschaften, besonders der Philosophie, dass es so einfach nicht ist festzustellen, wann etwas dieses Attribut beanspruchen kann. In den modernen Wissenschaften hat man dieses allgemeine Attribut durch ein spezifisches ersetzt: Als objektiv gilt, was empirisch erwiesen ist. Man hat die entsprechenden Verfahren auch in den Sozialwissenschaften angewandt, aber ist dabei, wie ich meine, einer sprachlich bedingten Tauschung erlegen. Man nennt die empirischen Wissenschaften auch Erfahrungswissenschaften – eine wortliche Ubersetzung. In den modernen Wissenschaften gilt aber nun keineswegs als empirisch dasjenige, was der Erfahrung im allgemeinsten Sinn entspricht. Empirisch heist hier: Experimente zu machen und diese Experimente zu beobachten, die dann als gultig angesehen werden, wenn sie sichtbar gemacht werden konnen. Man muss die Ergebnisse sehen konnen, entweder optisch – in Umrissen, Schwingungen, Kurven – oder dann in den niedergeschriebenen Zahlen und Zahlenverhaltnissen. In Kurzform tun dies auch die Interviews der empirischen Soziologie. Sie machen etwas lesbar und sichtbar. Empirie in diesem Sinn ist also durch zwei Bedingungen gegeben, einmal das Experiment (im weiteren Sinne), und zum anderen das Auge.