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Black carbon (BC) from incomplete combustion of biomass or fossil fuels is the strongest absorbing aerosol component in the atmosphere. Optical properties of BC are essential in climate models for quantification of their impact on radiative forcing. The global climate models, however, consider BC to be spherical particles, which causes uncertainties in their optical properties. Based on this, an increasing number of model-based studies provide databases and parameterization schemes for the optical properties of BC, using more realistic fractal aggregate morphologies. In this study, the reliability of the different modelling techniques of BC was investigated by comparing them to laboratory measurements. The modelling techniques were examined for bare BC particles in the first step and for BC particles with organic material in the second step. A total of six morphological representations of BC particles were compared, three each for spherical and fractal aggregate morphologies. In general, the aggregate representation performed well for modelling the particle light absorption coefficient σabs, single-scattering albedo SSA, and mass absorption cross-section MACBC for laboratory-generated BC particles with volume mean mobility diameters dp,V larger than 100 nm. However, for modelling Ångström absorption exponent AAE, it was difficult to suggest a method due to size dependence, although the spherical assumption was in better agreement in some cases. The BC fractal aggregates are usually modelled using monodispersed particles, since their optical simulations are computationally expensive. In such studies, the modelled optical properties showed a 25 % uncertainty in using the monodisperse size method. It is shown that using the polydisperse size distribution in combination with fractal aggregate morphology reduces the uncertainty in measured σabs to 10 % for particles with dp,V between 60–160 nm. Furthermore, the sensitivities of the BC optical properties to the various model input parameters such as the real and imaginary parts of the refractive index (mre and mim), the fractal dimension (Df), and the primary particle radius (app) of an aggregate were investigated. When the BC particle is small and rather fresh, the change in the Df had relatively little effect on the optical properties. There was, however, a significant relationship between app and the particle light scattering, which increased by a factor of up to 6 with increasing total particle size. The modelled optical properties of BC are well aligned with laboratory-measured values when the following assumptions are used in the fractal aggregate representation: mre between 1.6 and 2, mim between 0.50 and 1, Df from 1.7 to 1.9, and app between 10 and 14 nm. Overall, this study provides experimental support for emphasizing the importance of an appropriate size representation (polydisperse size method) and an appropriate morphological representation for optical modelling and parameterization scheme development of BC.

The formation of black carbon fractal aggregates (BCFAs) from combustion and subsequent ageing involves several stages resulting in modifications of particle size, morphology, and composition over time. To understand and quantify how each of these modifications influences the BC radiative forcing, the optical properties of BCFAs are modelled. Owing to the high computational time involved in numerical modelling, there are some gaps in terms of data coverage and knowledge regarding how optical properties of coated BCFAs vary over the range of different factors (size, shape, and composition). This investigation bridged those gaps by following a state-of-the-art description scheme of BCFAs based on morphology, composition, and wavelength. The BCFA optical properties were investigated as a function of the radius of the primary particle (ao), fractal dimension (Df), fraction of organics (forganics), wavelength (λ), and mobility diameter (Dmob). The optical properties are calculated using the multiple-sphere T-matrix (MSTM) method. For the first time, the modelled optical properties of BC are expressed in terms of mobility diameter (Dmob), making the results more relevant and relatable for ambient and laboratory BC studies. Amongst size, morphology, and composition, all the optical properties showed the highest variability with changing size. The cross sections varied from 0.0001 to 0.1 µm2 for BCFA Dmob ranging from 24 to 810 nm. It has been shown that MACBC and single-scattering albedo (SSA) are sensitive to morphology, especially for larger particles with Dmob > 100 nm. Therefore, while using the simplified core–shell representation of BC in global models, the influence of morphology on radiative forcing estimations might not be adequately considered. The Ångström absorption exponent (AAE) varied from 1.06 up to 3.6 and increased with the fraction of organics (forganics). Measurement results of AAE ≫ 1 are often misinterpreted as biomass burning aerosol, it was observed that the AAE of purely black carbon particles can be ≫ 1 in the case of larger BC particles. The values of the absorption enhancement factor (Eλ) via coating were found to be between 1.01 and 3.28 in the visible spectrum. The Eλ was derived from Mie calculations for coated volume equivalent spheres and from MSTM for coated BCFAs. Mie-calculated enhancement factors were found to be larger by a factor of 1.1 to 1.5 than their corresponding values calculated from the MSTM method. It is shown that radiative forcings are highly sensitive to modifications in morphology and composition. The black carbon radiative forcing ΔFTOA (W m−2) decreases up to 61 % as the BCFA becomes more compact, indicating that global model calculations should account for changes in morphology. A decrease of more than 50 % in ΔFTOA was observed as the organic content of the particle increased up to 90 %. The changes in the ageing factors (composition and morphology) in tandem result in an overall decrease in the ΔFTOA. A parameterization scheme for optical properties of BC fractal aggregates was developed, which is applicable for modelling, ambient, and laboratory-based BC studies. The parameterization scheme for the cross sections (extinction, absorption, and scattering), single-scattering albedo (SSA), and asymmetry parameter (g) of pure and coated BCFAs as a function of Dmob were derived from tabulated results of the MSTM method. Spanning an extensive parameter space, the developed parameterization scheme showed promisingly high accuracy up to 98 % for the cross sections, 97 % for single-scattering albedos (SSAs), and 82 % for the asymmetry parameter (g).

Main text This report presents the results of CCQM-K150, a key comparison between nine National Measurement Institutes (NMIs) which tested the capability of the NMIs to measure particle number concentration (in the range of 100 to 20 000 cm-3) using condensation particle counters (CPCs), and particle charge concentration (in the range of 0.15 to 3 fC cm-3) using aerosol electrometers (AEs). Measurements of aerosol particle number concentration are needed to demonstrate compliance to vehicle emission legislation and are becoming increasingly important in other areas such as ambient air and workplace monitoring. The measurements are typically carried out using condensation particle counters, which are calibrated using either reference CPCs or reference AEs. An analogous report is available for the CCQM-P189 comparison. CCQM-P189 was identical to and used the same experimental data as CCQM-K150 with one exception: data from TROPOS, which is not an NMI or Designated Institute (DI), were only included in CCQM-P189. CCQM-K150 was an amount-of-substance Track C comparison. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Main text This report presents the results of CCQM-P189, a pilot comparison between 10 laboratories which tested the participants’ capability to measure particle number concentration (in the range of 100 to 20 000 cm-3) using condensation particle counters (CPCs), and particle charge concentration (in the range of 0.15 to 3 fC cm-3) using aerosol electrometers (AEs). Measurements of aerosol particle number concentration are needed to demonstrate compliance to vehicle emission legislation and are becoming increasingly important in other areas such as ambient air and workplace monitoring. The measurements are typically carried out using condensation particle counters, which are calibrated using either reference CPCs or reference AEs. An analogous report is available for the CCQM-K150 comparison. CCQM-K150 was identical to, and used the same experimental data as CCQM-P189 with one exception: data from TROPOS, which is not a National Measurement Institute (NMI) or Designated Institute (DI), were only included in CCQM-P189. CCQM-P189 was an amount-of-substance Track C comparison. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The recovery of patients after general anesthesia is usually estimated by using clinical scores. Since there is a lack of objective methods for assessing psychomotor recovery, the aim of this study was to evaluate three psychological tests for this purpose. Patients, scheduled for ambulatory gynecological surgery, underwent 3 standard psychological tests before (T1), 15 min after the surgery (T2) and on discharge from the recovery room (T3). The tests used were Wechsler memory scale (test 1, working memory capacity), d2—test (test 2, concentration endurance) and computer-based 4-choice-reaction time (4CRT, test 3, reaction time) as well as Postanesthesia Discharge Scoring System (PADSS). The same test battery was used in healthy female volunteers, all test results were compared at the different time points. In 109 patients, working memory capacity and concentration (tests 1 and 2) decreased, the reaction time (test 3) was prolonged at T2 in comparison with T1 and T3 (P

The formation of black carbon fractal aggregates (BCFAs) from combustion and subsequent aging involves several stages resulting in modifications of particle size, morphology, and composition over time. To understand and quantify how each of these modifications influences the BC radiative forcing, the radiative properties of BCFAs are modelled. Owing to the high computational time involved in numerical modelling, there are some gaps in terms of data coverage and knowledge regarding how radiative properties of coated BCFAs vary over the range of different factors (size, shape, and composition). This investigation bridged those gaps by following a state-of-the-art description scheme of BCFAs based on morphology, composition, and wavelength. The BCFAs radiative properties were investigated as a function of the radius of the primary particle (ao), fractal dimension (Df), fraction of organics (forganics), wavelength (λ), and mobility diameter (Dmob). The radiative properties are calculated using the multiple sphere T-matrix (MSTM) method. Amongst size, morphology, and composition, all the radiative properties showed the highest variability with changing size. The cross-sections varied from 0.0001 μm2 to 0.1 μm2 for BCFA Dmob ranging from 24 nm to 810 nm. After size or Dmob, the absorption cross-section (Cabs) and BC mass absorption cross-section (MACBC) showed the highest sensitivity towards composition or forganics, whereas the asymmetry parameter (g) showed higher dependence on morphology, which is represented by Df. The Ångstrom absorption exponent varied from 1.06 up to 3.6 and increases with the fraction of organics (forganics). The values of the absorption enhancement factor (Eλ) were found between 1.01 and 3.28 in the visible spectrum. The Eλ was derived from Mie calculations for coated volume equivalent spheres, and from MSTM for coated BCFAs. Mie calculated enhancement factors were found to be larger by a factor of 1.1 to 1.5 than their corresponding values calculated from the MSTM method. It is shown that radiative forcings are highly sensitive towards modifications in morphology and composition. The black carbon radiative forcing ΔFTOA (Wm−2) decreases up to 61 % as the BCFA becomes more compact in morphology. Whereas, there is a decrease of > 50 % in ΔFTOA as the organic content of the particle increase up to 90 %. Based on our results, which showed a significant effect of coating and morphology on the BC radiative properties, a parametrization scheme for radiative properties of BC fractal aggregates was developed, which is applicable for modelling, ambient, and laboratory-based BC studies. The parameterization scheme for the cross-sections (extinction, absorption, and scattering), single scattering albedo (SSA), and asymmetry parameter (g) of pure and coated BCFAs as a function of Dmob were derived from tabulated results of the MSTM method. Spanning over an extensive parameter space, the developed parametrization scheme showed promisingly high accuracy up to 98 % for the cross-sections, 97 % for single scattering albedos (SSA), and 82 % for asymmetry parameter (g).

Atmospheric aerosol particles can significantly impact the atmospheric radiative balance by scattering and absorbing incoming solar radiation. Additionally, they are known to strongly affect human health. Given the strong variations in geographical distribution of atmospheric aerosols there is a high need for ubiquitous measurements, while the variable chemical composition generates several technical and metrological challenges. Absorption photometers are commonly used to measure the atmospheric mass concentration of light‑absorbing particles like equivalent black carbon (BCe), which is the most important radiative forcer among aerosol particles due to its strong infrared to visible spectral absorption. Although BC measurements have been done since decades, a reliable metrological aerosol absorption standard to ensure traceable calibration has not been established so far. Due to the wide field implementation there is strong need for a portable, metrological generator of BC-like aerosol particles for in‑field calibration of aerosol absorption photometers. Spark discharge volatilization is an interesting candidate for a BC particle generator, given its robust operation principle and the reduced media requirements.The spark discharge aerosol generator (SDAG) produces graphitic, BC-like aerosol particles. Most important is the lack of any organic coatings, known from spray or combustion generators, which usually alter the optical properties of the BC particles. The SDAG consists of a chamber purged with an inert gas (usually nitrogen or argon), which houses two graphite electrodes, which are connected to a pulsed high-voltage source with variable pulse frequency and amplitude. In this study, a PALAS DNP 3000 (PALAS GmbH, Germany) has been used for generating graphitic particles and measure their optical properties, aerosol number size distribution and particle morphology by scanning electron microscopy in transmission mode (TSEM). The SDAG was operated by using inert N2 only (avoiding dilution air), in order to facilitate the transportability and in-field operation. The N2 flow rate was fixed to 10 l/min. The spark discharge frequency spanned 60 to 600 Hz. The voltage was varied from 2500 to 5000 V.The mobility count mean diameter (CMD) of the particles produced could be varied from 28 to 80 nm, using the different set points described above. The single scattering albedo of the aerosol particles was almost constant for all operation modes with an average 0.11 ± 0.03. A repeatability analysis over 9 days was done using a single setting mode (140 Hz, 3500 V), which produced particles of 45 nm CMD with a variability of 6 nm CMD (2σ). The total particle number concentration ranged from 8 to 11 x 106 cm-3 and varied within 8% (1σ) within the different days. Hence, the SDAG is a promising source of stable, nascent and uncoated, graphitic BC particles and thus has good potential to improve field BC calibration.This research is part of an international project that aims to establish a BC reference material and calibration procedure (EMPIR 16ENV02 ”Black Carbon”, http://www.empirblackcarbon.com/).

Tracheotomies are common procedures in ventilated intensive care patients. They can be associated with severe complications, including fatal outcome. The complications bleeding, pneumothorax, tracheal posterior wall injuries, intraoperative loss of the respiratory tract, loss of the respiratory tract during tracheostomy tube changes, tracheal ring fractures, tracheal stenoses and stoma infections are clearly presented for the various procedures and methods in numerous illustrations, tables and text descriptions, and strategies for their avoidance are discussed in detail. The complications are defined for the first time in the literature by comparing concrete data. The performance of PDT with rigid endoscopic control is described in detail under interdisciplinary aspects. A separate section is dedicated to tracheotomy-related deaths. The chapter is compulsory reading for the practicing physician in his central concern to avoid complications and a helpful orientation for the expert.

Long-term intubations may cause various types of damage to the upper respiratory tract, which should be avoided with a tracheotomy. The chapter contains detailed explanations of frequent causes for tracheotomies. The advantages and disadvantages of this procedure are described in detail and the indications and contraindications for both surgical tracheotomies and percutaneous dilatational tracheotomies are shown.

Study objective Previous randomized controlled trials (RCTs) suggest that auricular stimulation (AS) is safe and effective in treatment of preoperative anxiety; however, a systematic evaluation is lacking. The aim was to summarize the evidence on efficacy and safety of AS for preoperative anxiety, as well as for other outcomes. Design We conducted a systematic review of RCTs including patients from all available populations. The search was done through MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science and Scopus Database from inception to June 2020. Study selection and data extraction were performed in by 2 independent reviewers with ability to resolve disagreements by a third author. Meta-analyses as well as the risk of bias and evidence quality assessments were performed according to the Cochrane 6.2, 2021 handbook recommendations. Interventions We compared AS with pharmacological and non-pharmacological interventions for different outcomes. Measurements We assessed the repercussion of the evaluated interventions over anxiety scores and their safety, physiological parameters, perioperative medications requirement and intensity of postoperative pain. Main results We have included 15 studies with 1603 patients. AS has presented reduced anxiety scores as compared to the sham control (Standardized Mean Difference (SMD) -0.72, 95% confidence interval (CI) -1.09 to −0.36, p Conclusions AS may be useful in treatment of preoperative anxiety. Due to heterogenous certainty in effect estimates, further research is needed to clarify the actual efficacy of AS for preoperative anxiety.

Marx's utterings on Africa are but dots and sprinkles across his entire oeuvre. Retracing them reveals changes in Marx's view on non-European societies. The early Marx praises the modernizing force of capital, while in his ethnological notebooks on Algeria there are critical perspectives on colonial policy. Marx's fragmented comments on Africa can only be understood in the context of colonialism and the integration of non-European societies into the web of bourgeois relations of production, world-wide capital expansion and the dynamics of non-capitalist societies.

Dermatoporosis is an important clinical condition leading to chronic skin fragility. It can be separated into primary and secondary subtypes, with the latter induced by medical drugs and environmental factors. Dermatoporosis can be classified into 4 major stages with increasing morbidity and mortality with the advanced stages. Its aetiology has been related to the epidermal hyalusome. Dermatoporosis is a cause of mortality in the intensive care unit and should be known not only by a dermatologist but another medical speciality as well. Prevention is of major importance. Therapeutic options are limited but available.

To estimate the incidence density, point prevalence and outcome of severe sepsis and septic shock in German intensive care units (ICUs).In a prospective, multicentre, longitudinal observational study, all patients already on the ICU at 0:00 on 4 November 2013 and all patients admitted to a participating ICU between 0:00 on 4 November 2013 and 2359 hours on 1 December 2013 were included. The patients were followed up for the occurrence of severe sepsis or septic shock (SEPSIS-1 definitions) during their ICU stay.A total of 11,883 patients from 133 ICUs at 95 German hospitals were included in the study, of whom 1503 (12.6 %) were diagnosed with severe sepsis or septic shock. In 860 cases (57.2 %) the infections were of nosocomial origin. The point prevalence was 17.9 % (95 % CI 16.3-19.7).The calculated incidence rate of severe sepsis or septic shock was 11.64 (95 % CI 10.51-12.86) per 1000 ICU days. ICU mortality in patients with severe sepsis/septic shock was 34.3 %, compared with 6 % in those without sepsis. Total hospital mortality of patients with severe sepsis or septic shock was 40.4 %. Classification of the septic shock patients using the new SEPSIS-3 definitions showed higher ICU and hospital mortality (44.3 and 50.9 %).Severe sepsis and septic shock continue to be a frequent syndrome associated with high hospital mortality. Nosocomial infections play a major role in the development of sepsis. This study presents a pragmatic, affordable and feasible method for the surveillance of sepsis epidemiology. Implementation of the new SEPSIS-3 definitions may have a major effect on future epidemiological data.

Sentinel lymph node biopsy is an established technique for melanoma staging. There are no studies available comparing different techniques for the removal of sentinel lymph nodes related to safety and postsurgical complication rate. This is a retrospective single-center trial. We analyzed the postsurgical complications in 201 consecutive melanoma patients with ligature of lymphatic vessels by sutures (group A) and in 91 consecutive patients with occlusion of lymphatic vessels by bipolar tweezers (group B). We paid particular attention to complications related to disturbed lymphatic function, such as lymph edema, lymphatic fistula, and seroma. The complication rate was 5.5 % (group A) and 9.6 % (group B) which is in the range of other published trials (p = 0.89). There was no increase of complications related to lymphatic vessels in group B, although the rate of patients with more than two sentinel lymph nodes removed was 5‑times higher than in group A. Removal of sentinel lymph nodes with the use of bipolar tweezers does not increase the risk of postsurgical complications, and in particular it is not associated with a higher rate of complications related to lymphatic vessel dysfunction.

In this investigation, we summarize performance parameters of 24 TSI CPCs model 3772 and 9 TSI CPCs model 3790 determined at the World Calibration Aerosol Centre Physics hosted by the Leibniz Institute for Tropospheric Research. Model 3790 CPCs are basically identical to model 3772 laminar continuous flow type butanol-based CPCs with a modified temperature difference between saturator and condenser. The average 50% detection efficiency for silver particles for 3772 and 3790 instruments was found to be 7.52 ± 0.04 nm and 24.34 ± 0.29 nm (average mobility diameter ± standard deviation), respectively. Small changes of the temperature difference between saturator and condenser cause larger shifts of the 50% detection efficiencies of 3790 CPCs compared to 3772 CPCs. In addition to the known calibration material dependence of the 50% detection efficiencies of 3790 CPCs, we found a dependence on the morphology of the particles used for calibration. In our experiments more spherical particles shifted the ...

Multiple-charge inversion is an essential procedure to convert the raw mobility distributions recorded by mobility particle size spectrometers, such as the DMPS or SMPS (differential or scanning mobility particle sizers), into true particle number size distributions. In this work, we present a fast and easy-to-implement multiple-charge inversion algorithm with sufficient precision for atmospheric conditions, but extended functionality. The algorithm can incorporate size distribution information from sensors that measure beyond the upper sizing limit of the mobility spectrometer, such as an aerodynamic particle sizer (APS) or an optical particle counter (OPC). This feature can considerably improve the multiple-charge inversion result in the upper size range of the mobility spectrometer, for example, when substantial numbers of coarse particles are present. The program also yields a continuous size distribution from both sensors as an output. The algorithm is able to calculate the propagation of measurement errors, such as those based on counting statistics, into on the final particle number size distribution. As an additional aspect, the algorithm can perform all inversion steps under the assumption of non-spherical particle shape, including constant or size-dependent shape factors.

Lichen planus is a T-cell mediated autoimmune disorder affecting the skin and mucous membranes. Ulcerating lichen planus is uncommon mostly on oral and genital mucosa but not skin. Lichen planopilaris, however, is a subtype of lichen planus affection hair follicles and leading to permanent scarring alopecia. We report a case of lichen planopilaris of the scalp with multiple alopecic patches ulceration – a hitherto unreported clinical feature. The patient was treated surgically, and the defect could be closed by combined tissue advancement and extension.

BACKGROUND: Chronic ulcers of the scalp have a variety of underlying pathologies. In case of cancer patients, a second malignancy must be excluded.CASE REPORT: A 78-year-old female patient presented to our department with a large soft tissue defect on the frontotemporal left side. The lesion was about 3 cm in diameter with exposed bone and inflammatory soft tissue on the edges of the defect. About 35 years ago, she had undergone a combined neurosurgery with skull trepanation and radiotherapy for an oligodendroglioma. Three years ago, sandwich transplantation with the dermal template and meshed skin graft failed. Now she re-presented with inflammatory ulcer borders. A complex defect repair was performed after exclusion of a second malignancy.CONCLUSION: Chronic scalp ulcers may be the result immunocompromised cutaneous districts and need a complex reconstruction.

Juxta-articular adiposis dolorosa is a rare subtype of Dercum's disease. It manifests mainly on the medial parts of the knees. Pain and impaired mobility are common symptoms. We report on four females (aged between 52 and 83 years) who suffered from juxta-articular adiposis dolorosa for more than 10 years. These patients were successfully treated by dermolipectomy resulting in dramatically improved pain and mobility. Adverse effects and complications were minor with a lymph fistula in a single patient which was treated by surgery.

Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor of the skin. Although its association with other malignancies is well known, an association with gastrointestinal stromal tumor (GIST) has yet not been described. We report about a 65-year-old female patient who presented with a hypervascularized subcutaneous tumor mass of her left calf. Resection of the primary tumor and histopathological investigations confirmed the diagnosis of MCC. The patient was treated by delayed Mohs surgery, and tumor-free margins were obtained. Sentinel lymph node biopsy was negative for metastatic spread. Primary tumor and lymph node basin were treated by adjuvant radiotherapy. During staging of the patient, a second malignancy—a GIST—was detected. Neoadjuvant treatment with multikinase inhibitor imatinib induced a partial response of GIST that was eventually removed by surgery. However, 8 months later, the patient developed subcutaneous regional metastases of MCC, which were surgically removed. Adjuvant therapy was planned by oncologists. To the best of our knowledge, the occurrence of MCC and GIST in the same patient has yet not been reported. In contrast to GIST, MCC did not respond to imatinib, although c-kit mutations are common in MCC.

Erysipelas are common soft tissue infections responding to first-line antibiosis. Because of factors of related to responsible bacteria and host, complications can occur that need extensive surgery in addition to intensified drug therapy. We report on a 65-year-old woman with leg ulcer who developed an absceding and necrotizing panniculitis of the affected leg complicating erysipelas. Escherichia coli and Pseudomonas aeruginosa were identified. Debridement and surgical removal of inflamed subcutaneous adipose tissue was decisive to interrupt the process. Wound bed preparation was realized by vacuum-assisted closure. Final wound closure was done by split-skin mesh graft. Complicated skin and skin structure infections need a combined approach of intensified antibiosis and surgery to save life.

Discussions on euthanasia (“Sterbehilfe”) that took place in the German Democratic Republic (GDR) have remained widely unnoticed by the historical sciences. By referring to various publications dating from the 1950s until today, this paper presents the basic ideas of the debate on euthanasia in the GDR and compares them—partly synchronically, partly diachronically—with the situation in the Federal Republic of Germany (FRG). A special focus is placed on positions and terminology related to medical ethics at the end of life in the former two German states. The methodical approach of the paper allows a transparent analysis of the question of whether the GDR debates on euthanasia are significant and independent, and whether they are relevant to current ethical debates on end-of-life practices in Germany.

Background Tracheotomies are frequently performed on ventilated patients in intensive care and sometimes lead to fatal complications. In this article, we discuss the causes and frequency of death associated with open surgical tracheotomy (OST) and percutaneous dilatational tracheotomy (PDT) on the basis of a review of the pertinent literature. Methods We systematically searched the PubMed, EMBASE, and Cochrane Library databases and the Karlsruhe Virtual Catalog for publications (1990-2015) on tracheotomy-related deaths in adults, using the search terms "tracheotomy" and "tracheostomy." 39 relevant dissertations were included in the analysis as well. Results 109 publications were included. Of the 25 056 tracheotomies described, there were 16 827 PDTs and 7934 OSTs; for 295 tracheotomies, the technique used was not stated. 352 deaths were reported, including 113 in patients treated with PDT, 49 in those treated with OST, and 190 deaths related to a tracheotomy without specification of the method used. The frequency of death among patients with OST and those treated with PDT was similar: 0.62% for OST (95% confidence interval [0.47; 0.82]) and 0.67% for PDT ([0.56; 0.81]). The most common causes of death and their frequencies, as a percentage of all tracheotomies, were hemorrhage (OST: 0.26% [0.17; 0.40], PDT: 0.26% [0.19; 0.35]), loss of airway (OST: 0.21% [0.13; 0.34], PDT: 0.20% [0.14; 0.28]), and false passage (OST: 0.11% [0.06; 0.22], PDT: 0.20% [KI 0.15; 0.29]). Conclusion Bias in the data cannot be excluded, as these were not epidemiologic data and the documentation was found to be incomplete. The likelihood of a fatal complication seems to be the same with both tracheotomy techniques as far as can be determined from the available evidence. Tracheotomy-related deaths can be avoided in several ways: by thorough training under the leadership of experienced physicians, by the use of the World Health Organization's Surgical Safety Checklist regardless of where the tracheotomy is performed, and by the continuous vigilance of nursing staff.

Discussions on euthanasia ("Sterbehilfe") that took place in the German Democratic Republic (GDR) have remained widely unnoticed by the historical sciences. By referring to various publications dating from the 1950s until today, this paper presents the basic ideas of the debate on euthanasia in the GDR and compares them-partly synchronically, partly diachronically-with the situation in the Federal Republic of Germany (FRG). A special focus is placed on positions and terminology related to medical ethics at the end of life in the former two German states. The methodical approach of the paper allows a transparent analysis of the question of whether the GDR debates on euthanasia are significant and independent, and whether they are relevant to current ethical debates on end-of-life practices in Germany.

Background Fiberoptic tracheo-bronchoscopy is the most commonly used procedure for percutaneous dilational tracheotomy (PDT). However, PDT can be associated with major complications, including death. Furthermore it is unclear, whether the tracheal ring fractures may contribute to the development of tracheal stenosis after PDT nor whether tracheal ring fractures can be prevented by using a rigid endoscope for this procedure. The purpose of this study was to evaluate the feasibility of and the incidence of complications for PDT using the rigid tracheotomy endoscope (TED). Methods In a prospective multicenter observational study from 2006 to 2010, 180 adult patients in intensive care and those scheduled for ear, nose and throat surgery underwent PDT using TED. Data collection was performed using a structured protocol. The patients were observed according to PDT phase (phase 1: puncture, phase 2: dilatation and phase 3: cannula insertion). The descriptive data are given as the number (percent) of cases and the mean ± standard deviation (SD) where appropriate. The relationships between dichotomous and categorical parameters were analyzed using the chi-square test. P values ≤ 0.05 were considered significant. Results PDT was performed in 179 patients. The procedure time was 14.8 ± 6.2 (mean ± SD) minutes. Pneumothorax or procedure-related lethal complications did not occur. Other adverse events included tracheal ring fractures (17.1%), desaturations (6.8%), special incidents (6.2%), bleeding (5.5%), anesthesia complications (4.5%) and posterior tracheal wall injuries (1.1%). Conclusion The use of TED in PDT is feasible, and the incidence of complications and adverse events was comparable with that of PDT using the flexible endoscope. Tracheal ring fractures in PDT cannot be avoided by the use of a rigid endoscope. With TED, the airway always remains open thus the use of jet ventilation via the TED during PDT is possible.

Particle number size distributions and hygroscopic properties of marine and Saharan dust aerosol were investigated during the SAMUM-2 field study at Cape Verde in winter 2008. Aitken and accumulation mode particles were mainly assigned to the marine aerosol, whereas coarse mode particles were composed of sea-salt and a variable fraction of Saharan mineral dust. A new methodical approach was used to derive hygroscopic growth and state of mixing for a particle size range (volume equivalent) from dpve= 26 nm to 10 μm. For hygroscopic particles with dpve < 100 nm, the median hygroscopicity parameter κ is 0.35. From 100 nm < dpve < 350 nm, κ increases to 0.65. For larger particles, κ at dpve= 350 nm was used. For nearly hydrophobic particles, κ is between 0 and 0.1 for dpve < 250 nm and decreases to 0 for dpve > 250 nm. The mixing state of Saharan dust in terms of the number fraction of nearly hydrophobic particles showed the highest variation and ranges from 0.3 to almost 1. This study was used to perform a successful mass closure at ambient conditions and demonstrates the important role of hygroscopic growth of large sea-salt particles.DOI: 10.1111/j.1600-0889.2011.00569.x

Mobility particle size spectrometers (MPSS) belong to the essential instruments in aerosol science that determine the particle number size distribution (PNSD) in the submicrometer size range. Following calibration procedures and target uncertainties against standards and reference instruments are suggested for a complete MPSS quality assurance program: (a) calibration of the CPC counting efficiency curve (within 5% for the plateau counting efficiency; within 1 nm for the 50% detection efficiency diameter), (b) sizing calibration of the MPSS, using a certified polystyrene latex (PSL) particle size standard at 203 nm (within 3%), (c) intercomparison of the PNSD of the MPSS (within 10% and 20% of the dN/dlogDP concentration for the particle size range 20–200 and 200–800 nm, respectively), and (d) intercomparison of the integral PNC of the MPSS (within 10%). Furthermore, following measurement uncertainties have been investigated: (a) PSL particle size standards in the range from 100 to 500 nm match within 1% after sizing calibration at 203 nm. (b) Bipolar diffusion chargers based on the radioactive nuclides Kr85, Am241, and Ni63 and a new ionizer based on corona discharge follow the recommended bipolar charge distribution, while soft X-ray-based charges may alter faster than expected. (c) The use of a positive high voltage supply show a 10% better performance than a negative one. (d) The intercomparison of the integral PNC of an MPSS against the total number concentration is still within the target uncertainty at an ambient pressure of approximately 500 hPa.

Metatypical basal cell carcinoma (MTBCC) represents a high-risk type of cutaneous tumour. We report about three different patients with relapsing advanced large MTBCC: one of the scalp and two of the cheek region. Such patients required in most of the cases a complex surgical approach to achieve a stable and complete remission. In the first presented patient a combination of flaps and grafts has been performed. We describe tailored surgical approaches. By this contrivance it is possible to treat even elderly patients with exposed bone after complete excision effectively and safe. Interdisciplinary team work is for the benefit of these patients.

Aerosol hygroscopic growth factors and chemical properties were measured as part of the MEGAPOLI "Megacities Plume Case Study" at the urban site Laboratoire d'Hygiène de la Ville de Paris (LHVP) in the city center of Paris from June to August 2009, and from January to February 2010. Descriptive hygroscopic growth factors (DGF) were derived in the diameter range from 25 to 350 nm at relative humidities of 30, 55, 75, and 90% by applying the summation method on humidified and dry aerosol size distributions measured simultaneously with a humidified differential mobility particle sizer (HDMPS) and a twin differential mobility particle sizer (TDMPS). For 90% relative humidity, the DGF varied from 1.06 to 1.46 in summer, and from 1.06 to 1.66 in winter. Temporal variations in the observed mean DGF could be well explained with a simple growth model based on the aerosol chemical composition measured by aerosol mass spectrometry (AMS) and black carbon photometry (MAAP). In particular, good agreement was observed when sulfate was the predominant inorganic factor. A clear overestimation of the predicted growth factor was found when the nitrate mass concentration exceeded values of 10 μg m−3, e.g., during winter.

Background Transcutaneous vagal nerve stimulation is a promising treatment modality in patients suffering mood disorders and chronic pain, however, the mechanisms are still to be elucidated. A recently developed technique of EEG responses to electrical stimulation of the inner side of the tragus suggests that these responses are far field potentials, generated in the vagal system – Vagal Sensory Evoked Potentials (VSEP). Objective To reproduce the VSEP technique free from myogenic artifacts. Methods Fourteen ASA I–II patients scheduled for elective surgery in standardized Total Intravenous Anesthesia (TIVA) were enrolled. Transcutaneous electrical stimulation was applied to the inner side of the right tragus. Averaged EEG responses were recorded from the electrode positions C4-F4 and T4-O2 before and after induction of TIVA, during the maximal effect of the non-depolarizing muscle relaxing agent, cis-atracurium (C-AR) and after recovery from C-AR under TIVA. Results Typical response curves with P1, N1 and P2 peaks could be reproduced in all patients before and after anesthesia induction. The response curves disappeared during the C-AR action and re-appeared after recovery from C-AR under TIVA. Conclusion The disappearance of the scalp responses to electrical tragus stimulation under the neuromuscular block suggests a muscular origin of these potentials.

Background Sentinel lymph node biopsy (SLNB) is an important tool for accurate staging of patients with melanoma. There is an ongoing debate whether the procedure provides therapeutic benefits or not. Objective We wanted to analyze 10-year data from an academic teaching hospital. Patients and methods During 1999–2009, 977 patients with early cutaneous melanoma have been treated. Of these, 419 patients had tumors ≥1 mm thickness. Patients with head and neck tumors were excluded, leaving 364 patients (202 men and 162 women). SLNB was not performed in 163 patients but was performed in 201 patients. For correction of bias, tumors >4 mm thickness were excluded from further statistical analysis. Results The detection rate of SLN was 94.4%. False negative SLN were observed in 8.9%. Adverse effects occurred in 5.5%. The rate of positive SLNB was 16.4% and lymph node involvement 20%. Patients undergoing SLNB had a lower relapse rate (10.6% vs. 33.3%; P

Acne inversa (AI) is a disabilitating chronic inflammatory disease with major negative impact on quality of life and significant co-morbidities. This is an important link to insights into immune dysfunction, which stimulated therapeutic approaches like tumor necrosis-α inhibitor therapy. This new off-label drug treatment is particularly beneficial when used in combination with wide excision of inflamed skin and subcutaneous tissue. Retinoids have been reported to be helpful in secondary prevention. The standard of therapy in advanced cases is surgery with wide excisions and healing by secondary intention. This treatment results in significant reduction of complaints and achieves satisfactory body contouring.

Introduction: The intensive care unit (ICU) represents a special environment for patients. We analyzed patients in the ICU/ high care unit (HCU) with respect to dermatology counselling and skin problems.Setting: Academic Teaching Hospital over a 10 month period.Methods: The total number of patients of the ICU was 1,208 with a mean stay of 4.1 days. In the HCU the mean stay was 16 days. Diagnosis leading to admission were analyzed. All files of dermatological counselling were evaluated in detail.Results: Fifty-five patients with dermatologic problems were identified: 19 women and 26 males. The age ranged from 22 to 90 years of life (mean ± standard deviation: 67.2 ± 17.4 years). The total number of consultations were 85. The range of repeated dermatological consultation ranged from two to ten. The major reasons were skin and soft tissue infections, adverse drug reactions, chronic wounds including pressure sores and skin irritation or dermatitis. Pre-existing skin conditions may complicate the treatment and care during ICU/HCU stay.Conclusion: A tight collaboration between of the medical staff of ICU/HCU and dermatology department will ensure a rapid diagnosis and treatment of various skin conditions in the ICU, without increasing the costs significantly. Interdisciplinary education of nursing staff contributes to improved skin care in the ICU/HCU and helps to prevent acute skin failure.