Secondary tension pneumothorax in a COVID-19 pneumonia patient: a case report

PURPOSE Especially in elderly and multimorbid patients, Coronavirus Disease 2019 (COVID-19) may result in severe pneumonia and secondary complications. Recent studies showed pneumothorax in rare cases, but tension pneumothorax has only been reported once. CASE PRESENTATION A 47-year-old male was admitted to the emergency department with fever, dry cough and sore throat for the last 14~days as well as acute stenocardia and shortage of breath. Sputum testing (polymerase chain reaction, PCR) confirmed SARS-CoV-2 infection. Initial computed tomography (CT) showed bipulmonary groundglass opacities and consolidations with peripheral distribution. Hospitalization with supportive therapy (azithromycin) as well as non-invasive oxygenation led to a stabilization of the patient. After 5~days, sputum testing was negative and IgA/IgG antibody titres were positive for SARS-CoV-2. The patient was discharged after 7~days. On the 11th day, the patient realized pronounced dyspnoea after coughing and presented to the emergency department again. CT showed a right-sided tension pneumothorax, which was relieved by a chest drain (Buelau) via mini open thoracotomy. Negative pressure therapy resulted in regression of the pneumothorax and the patient was discharged after 9~days of treatment. CONCLUSION Treating physicians should be aware that COVID-19 patients might develop severe secondary pulmonary complications such as acute tension pneumothorax. LEVEL OF EVIDENCE V

High prevalence of missed information related on bone health in orthogeriatric patients with fragility fractures of the pelvis-an institutional register-based analysis

This is the first study that highlighted the amount of missed information related on bone health in orthogeriatric patients suffering fragility fractures of the pelvis and also evaluated its prevalence and differing etiology in the assessed patients, regarding osteoporosis and/or osteomalacia, based on laboratory and instrumental measurements. This evaluation should become a standardized procedure in the treatment of orthogeriatric patients presenting with a FFP. INTRODUCTION Fragility fractures of the pelvis (FFP) are common in orthogeriatric patients. Secondary fracture prevention regarding evaluation and treatment of an underlying osteoporosis or osteomalacia is still often neglected. The purpose of this study was to evaluate the amount of missed information related on bone health in older adult FFP patients, the prevalence of vitamin D deficiency in assessed patients, and if fracture type-dependent distribution patterns could be observed. METHODS A retrospective analysis of prospectively collected data of an institutional register was performed. Patients aged 80~years and older (n = 456) admitted with a FFP from 01/2003 until 12/2019 to a level I trauma center were included. RESULTS In 456 patients, FFP type II were leading (66.7%). Diagnostics were conducted in 37.1% of the patients regarding measurement of vitamin D levels and 21.7% regarding DXA measurements; vitamin D deficiency was observed in 62.7%, indicators for an underlying osteomalacia in 45.8%, and an osteoporosis in 46.5% of the assessed patients. CONCLUSION Although FFP are common and will increase, there is still a lack of secondary fracture prevention, starting with information related on bone health. In the assessed patients, a high prevalence of vitamin D deficiency was present, but no significant correlation between vitamin D level and type of fracture was observed. Ongoing education for varying etiology and specific treatment of these fractures is necessary, as surgical treatment was unified, but drug therapy remains different

Comparison of experimental results from three dual fluidized bed test facilities capturing CO2 with CaO

10th International Conference on Greenhouse Gas Control Technologies[EN] Postcombustion CO2 capture technologies using CaO as a regenerable solid sorbent have emerged as a promising route to reduce the electricity penalty and the cost of CO2 capture from flue gases of both new and existing fossil fuelled power plants. Rapid progress is taking place in the understanding of these processes at different levels. However, experimental information, validating the concept under continuous operating conditions similar to those expected for large-scale application, remain scarce. We present here a comparative analysis of the results obtained in three laboratory-scale dual fluidized bed (DFB) test facilities in Spain, Germany and Canada. The test facilities range from 10 to 75 kWth with riser heights between 4.5 and 12.4 m. They have been operated to capture CO2 with CaO from simulated flue gases in the bubbling, turbulent and fast fluidization fluid-dynamic regimes. The carbonator reactors are interconnected with regenerators, where the CaCO3 decomposition has been conducted continuously and semi-continuously, operated in both air-combustion and oxy-combustion modes. Many stationary and non-stationary states have been achieved at different combinations of the key operating parameters (e.g. calcium looping ratio). All DFB test facilities showed a carbon balance closure of high quality in most tests. The trends of CO2 capture efficiency with respect to operating conditions and sorbent characteristics are compared and a discussion is made on the most appropriate methodology to conduct future tests under a joint new FP7 project (CaOling) that aims at the rapid scaling up of the calcium looping technology.This work is being funded by the European Commision 7th Framework Programme under the CaOling Project.Peer reviewe

Finding and counting vertex-colored subtrees

The problems studied in this article originate from the Graph Motif problem introduced by Lacroix et al. in the context of biological networks. The problem is to decide if a vertex-colored graph has a connected subgraph whose colors equal a given multiset of colors $M$. It is a graph pattern-matching problem variant, where the structure of the occurrence of the pattern is not of interest but the only requirement is the connectedness. Using an algebraic framework recently introduced by Koutis et al., we obtain new FPT algorithms for Graph Motif and variants, with improved running times. We also obtain results on the counting versions of this problem, proving that the counting problem is FPT if M is a set, but becomes W[1]-hard if M is a multiset with two colors. Finally, we present an experimental evaluation of this approach on real datasets, showing that its performance compares favorably with existing software.Comment: Conference version in International Symposium on Mathematical Foundations of Computer Science (MFCS), Brno : Czech Republic (2010) Journal Version in Algorithmic

Ultrametric spaces of branches on arborescent singularities

Let $S$ be a normal complex analytic surface singularity. We say that $S$ is arborescent if the dual graph of any resolution of it is a tree. Whenever $A,B$ are distinct branches on $S$, we denote by $A \cdot B$ their intersection number in the sense of Mumford. If $L$ is a fixed branch, we define $U_L(A,B)= (L \cdot A)(L \cdot B)(A \cdot B)^{-1}$ when $A \neq B$ and $U_L(A,A) =0$ otherwise. We generalize a theorem of P{\l}oski concerning smooth germs of surfaces, by proving that whenever $S$ is arborescent, then $U_L$ is an ultrametric on the set of branches of $S$ different from $L$. We compute the maximum of $U_L$, which gives an analog of a theorem of Teissier. We show that $U_L$ encodes topological information about the structure of the embedded resolutions of any finite set of branches. This generalizes a theorem of Favre and Jonsson concerning the case when both $S$ and $L$ are smooth. We generalize also from smooth germs to arbitrary arborescent ones their valuative interpretation of the dual trees of the resolutions of $S$. Our proofs are based in an essential way on a determinantal identity of Eisenbud and Neumann.Comment: 37 pages, 16 figures. Compared to the first version on Arxiv, il has a new section 4.3, accompanied by 2 new figures. Several passages were clarified and the typos discovered in the meantime were correcte

The influence of information-based Transport Demand Management measures on commuting mode choice. Comparing web vs. face-to-face surveys

We test the effect of different contextualization, scaling, framing and formatting of environmental impacts and health benefits information on commuting mode choice. For this, a stated preference (SP) survey was designed. To also test survey mode effect, the survey was administrated both online and face-to-face. We find statistical differences across the two samples in terms of transport preferences, attitudes and perceptions towards the environment, health and social norms. These could be attributed both to differences in the levels of education and professional occupation and self-selection bias. The results in the models estimated from the SP hint the existence of irrational answers in the web-based sample. Information about global CO2 emissions appears to be ineffective in influencing mode choice whereas self-centric information about calories consumption is effective

Growth factor-mediated augmentation of long bones: evaluation of a BMP-7 loaded thermoresponsive hydrogel in a murine femoral intramedullary injection model

Background Due to our aging population, an increase in proximal femur fractures can be expected, which is associated with impaired activities of daily living and a high risk of mortality. These patients are also at a high risk to suffer a secondary osteoporosis-related fracture on the contralateral hip. In this context, growth factors could open the field for regenerative approaches, as it is known that, i.e., the growth factor BMP-7 (bone morphogenetic protein 7) is a potent stimulator of osteogenesis. Local prophylactic augmentation of the proximal femur with a BMP-7 loaded thermoresponsive hydrogel during index surgery of an osteoporotic fracture could be suitable to reduce the risk of further osteoporosis-associated secondary fractures. The present study therefore aims to test the hypothesis if a BMP-7 augmented hydrogel is an applicable carrier for the augmentation of non-fractured proximal femurs. Furthermore, it needs to be shown that the minimally invasive injection of a hydrogel into the mouse femur is technically feasible. Methods In this study, male C57BL/6 mice (n = 36) received a unilateral femoral intramedullary injection of either 100 μl saline, 100 μl 1,4 Butan-Diisocyanat (BDI)-hydrogel, or 100 μl hydrogel loaded with 1 μg of bone morphogenetic protein 7. Mice were sacrificed 4 and 12 weeks later. The femora were submitted to high-resolution X-ray tomography and subsequent histological examination. Results Analysis of normalized CtBMD (Cortical bone mineral density) as obtained by X-ray micro-computed tomography analysis revealed significant differences depending on the duration of treatment (4 vs 12 weeks; p < 0.05). Furthermore, within different anatomically defined regions of interest, significant associations between normalized TbN (trabecular number) and BV/TV (percent bone volume) were noted. Histology indicated no signs of inflammation and no signs of necrosis and there were no cartilage damages, no new bone formations, or new cartilage tissues, while BMP-7 was readily detectable in all of the samples. Conclusions In conclusion, the murine femoral intramedullary injection model appears to be feasible and worth to be used in subsequent studies that are directed to examine the therapeutic potential of BMP-7 loaded BDI-hydrogel. Although we were unable to detect any significant osseous effects arising from the mode or duration of treatment in the present trial, the effect of different concentrations and duration of treatment in an osteoporotic model appears of interest for further experiments to reach translation into clinic and open new strategies of growth factor-mediated augmentation