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Carbonaceous deposits formed in fuel-film cooling act as a thermally insulating barrier, but the mechanisms for their formation at the high enthalpies and pressures of rocket engines are not well studied. Various spectroscopic techniques were used to investigate the microscopic chemical and physical structure of carbonaceous deposits formed in a small-scale H2O2-kerosene rocket combustor. Where possible, spectra were measured as a function of axial distance from the fuel-film injector to identify changes in deposit structure as the fuel-film boundary layer vaporized and mixed with the hot core flow. Two carbon layers were found, a tenacious dense layer beneath a porous soot layer. Gas chromatography mass spectrometry was used to determine condensable polycyclic aromatic hydrocarbon (PAH) concentrations in the dense and soot deposits. Raman spectroscopy measured planar coherence length and other indicators of structural order while x-ray photoelectron spectroscopy determined carbon hybridization, surface oxidation, and deposit impurities. All three of these spectroscopy techniques showed independent signs of the dense layer forming via heterogeneous condensation of heavy PAHs, whereas the soot layer deposited via thermophoresis.

PURPOSE OF THE STUDY Minimal and limited access techniques are gaining increasing interest for the treatment of displaced intra-articular calcaneal fractures. The ideal treatment method is however still debated and largely based on individual case factors and surgeon experience. Aim of this study was thus to compare the treatment characteristics and radiographic correction potential of a locking nail system with a sinus tarsi approach to plate fixation via an extended lateral approach. MATERIAL AND METHODS We retrospectively reviewed 39 cases of patients with calcaneal fractures that received primary fracture treatment for displaced intra-articular calcaneal fractures between July 2017 and March 2020. Patient characteristics, time to surgery, time to discharge, OR time and the correction achieved were analyzed and comparative statistics performed. RESULTS In total 19 patients treated with the locking nail and 20 patients treated with plate fixation were analyzed. Patient age and fracture severity according to the Sanders classification were comparable between the groups. Overall surgical time, as well as the achieved reduction was equal between both groups. Time to surgery, as well as time from surgery to discharge was significantly shorter in the locking nail group. 2 additional soft tissue procedures were necessary in the extended lateral approach group. DISCUSSION AND CONCLUSIONS The results with the locking calcaneus nail and sinus tarsi approach suggest, that similar treatment results can be achieved as with plate osteosynthesis and an extended lateral approach. Soft tissue management, as well as pre- and postoperative timing and discharge management can be improved with the nail. Further controlled trials comparing the longterm outcome between the treatment options are needed. Key words: calcaneus fracture, sinus tarsi approach, calcaneal nail, C-Nail.

Surgical treatment of acetabular fractures represents a special challenge in the field of trauma surgery. Complications are mostly due to the trauma itself or are iatrogenic. The handling and strategy to overcome complications in acetabular surgery are oriented towards the type of complication and the time of occurrence. Generally, a differentiation is made between early perioperative complications and late complications. The present article describes the most frequent complications during the surgical treatment of acetabular fractures, discusses the various treatment options based on individual case examples and gives differentiated recommendations to overcome the complications. The treatment concept should initially comprise a comprehensive primary prophylaxis to prevent complications. In cases of early perioperative complications, e.g. postoperative wound infections, hemorrhage or incorrect implant positioning, rapid and systematic surgical revision should be performed. In contrast, the treatment of late complications (e.g. implant associated failures, secondary osteoarthrosis of the hip, periarticular heterotopic ossification, non-unions and late infections) depends on the clinical and functional condition of the patient. In symptomatic elderly patients secondary total hip replacement is usually a valid option, whereas younger patients with late complications can be candidates for joint-preserving procedures. The management of complications in acetabular surgery regularly requires intense patient guidance as well as thorough clarification and should be performed in specialized centers.Die operative Behandlung von Acetabulumfrakturen stellt eine besondere Herausforderung in der Unfallchirurgie dar. Komplikationen sind meist durch den Unfall selbst oder iatrogen bedingt. Der Umgang und die Strategie zur Bewältigung von Komplikationen in der Acetabulumchirurgie richten sich nach der Art und dem Zeitpunkt ihres Auftretens. Generell werden perioperative Frühkomplikationen von Spätkomplikationen unterschieden. Der vorliegende Beitrag stellt die häufigsten Komplikationen in der operativen Behandlung von Acetabulumfrakturen dar, diskutiert die verschiedenen Therapiemöglichkeiten anhand einzelner Fallbeispiele und gibt differenzierte Empfehlungen. Das Versorgungskonzept sollte zunächst eine umfassende Primärprophylaxe zur Vermeidung von Komplikationen umfassen. Eingetretene Frühkomplikationen wie z. B. postoperative Infektionen, Blutungen oder Implantatfehllagen sollten rasch und konsequent im Sinne einer Sekundärprophylaxe chirurgisch behandelt werden. Hingegen richtet sich die Behandlung von Spätkomplikationen (Implantatlockerungen und -brüche, sekundäre Koxarthrose, heterotope Ossifikationen, Pseudarthrosen und Spätinfektionen) nach dem klinischen und funktionellen Beschwerdebild des Patienten. Bei älteren Patienten mit entsprechenden Beschwerden stellt die sekundäre Versorgung mit einer Hüfttotalendoprothese oftmals eine gute Behandlungsmöglichkeit dar, wohingegen bei jüngeren Patienten nach Spätkomplikationen auch gelenkerhaltende Verfahren infrage kommen. Das Management von Komplikationen in der Acetabulumchirurgie erfordert regelhaft eine enge Patientenführung sowie die ausführliche Aufklärung und Beratung der Patienten und sollte in spezialisierten Zentren erfolgen.

Introduction Femoral neck fractures (FNF) are one of the most frequent fractures among elderly patients and commonly require surgical treatment. Bipolar hip hemiarthroplasty (BHHA) is mostly performed in these cases. Material and methods In the present retrospective study geriatric patients with FNF (n = 100) treated either by anterior minimal-invasive surgery (AMIS; n = 50) or lateral conventional surgery (LCS; n = 50) were characterized (age at the time of surgery, sex, health status/ASA score, walking distance and need for walking aids before the injury) and intraoperative parameters (duration of surgery, blood loss, complications), as well as postoperative functional performance early (duration of in-patient stay, radiological leg length discrepancy, ability to full weight-bearing, mobilization with walking aids) and 12 months (radiological signs of sintering, clinical parameters, complication rate) after surgery were analyzed. Results Patients in the AMIS group demonstrated a reduced blood loss intraoperatively, while the duration of surgery and complication rates did not differ between the two groups. Further, more patients in the AMIS group achieved full weight-bearing of the injured leg and were able to walk with a rollator or less support during their in-patient stay. Of interest, patients in the AMIS group achieved this level of mobility earlier than those of the LCS group, although their walking distance before the acute injury was reduced. Moreover, patients of the AMIS group showed equal leg lengths postoperatively more often than patients of the LCS group. No significant differences in functional and surgery-related performance could be observed between AMIS and LCS group at 12 months postoperatively. Conclusions In conclusion, geriatric patients treated by AMIS experience less surgery-related strain and recover faster in the early postoperative phase compared to LCS after displaced FNF. Hence, AMIS should be recommended for BHHA in these vulnerable patients.

PURPOSE OF THE STUDY Most common postoperative treatment recommendations after acetabulum fractures suggest at least 6 weeks of postoperative partial or non weight-bearing. To protect the osteosynthetic construct this surgically set weight-bearing limit is trained by physical therapy. Aim of our analysis was to determine the free field patient compliance to these weight-bearing restrictions and observe their influence on the early postoperative radiographic imaging. MATERIAL AND METHODS Patients after surgical treatment of an acetabulum fracture were included in our analysis. Every patient was instructed to maintain a 20 kg weight-bearing limit for 6 weeks. Postoperative weight-bearing was continuously monitored during this time with a pressure measuring insole. Maximum weight-bearing per day was recorded and maintenance of reduction assessed after this time. RESULTS In total 10 patients were included into the study. Only 1 patient stayed within the weight-bearing limit during the analysis. Maximum weight-bearing as high as 110 kg was recorded. All patients maintained postoperative reduction at the 6 week timepoint. DISCUSSION AND CONCLUSIONS Despite regular physical therapy training compliance to the generally accepted weight-bearing limits was low. Regardless of the non-compliance the radiographic outcome remained unchanged. Further analysis on the use of permissive weightbearing aftercare regimes are warranted. Key words: weight-bearing, acetabulum fracture, compliance.

The emergency department (ED) is the main port of entry for patients with infectious diseases, the place where a number of diagnostic procedures are performed and treatment is often initiated. The aim of this retrospective study was to estimate the influence of the establishment and introduction of a blood culture standard operating procedure (BC-SOP) and of the subsequent training of microbial diagnostics in an ED.In a before and after study over a study period of 3 months each (November 2017-January 2018 and November 2018-January 2019), the number of blood cultures taken, the rate of blood cultures per 1000 patients, the number of positive blood cultures and the frequency of typical skin pathogens were evaluated. In the interim time between the two study periods, a BC-SOP was developed in collaboration with the hospital's antibiotic stewardship team and subsequently introduced with staff training in the ED. The study was approved by the local ethics committee of the medical faculty of the Heinrich Heine University (2019-392-RetroDEuA).In total 92% of the nursing personnel and 93% of the medical personnel received training. The total number of blood cultures increased from 1757 to 2872 (64% increase) and the rate of blood cultures per 1000 patients from 287 to 481 (68% increase). The number of positive blood cultures decreased from 18.6% to 13.7% (p 0.05). Typical skin pathogens were found in 34.4% and 26.4% of the cases, respectively (p 0.05).The development, introduction and training of a BC-SOP in the ED can make a relevant contribution to the microbial diagnostics and increase the quantity as well as the quality.EINLEITUNG: Zentrale Notaufnahmen stellen die Eintrittspforte für viele stationär aufzunehmende Patienten in einem Krankenhaus dar und sind häufig der Ausgangspunkt für die antiinfektive Diagnostik und Therapie von Notfallpatienten. In dieser retrospektiven Untersuchung soll der Frage nachgegangen werden, wie die Etablierung einer Standard Operating Procedure (SOP) „Blutkulturen“ und deren Schulung die mikrobielle Diagnostik in einer zentralen Notaufnahme verbessern kann.In einer Vorher-und-nachher-Untersuchung wurde über einen jeweils 3‑monatigen Zeitraum (11/2017 bis 01/2018 und 11/2018 bis 01/2019) die Anzahl der abgenommenen Blutkulturen, die Rate an Blutkulturen/1000 Fälle, die Anzahl positiver Blutkulturen und die Häufigkeit typischer Hautkeime analysiert. Im Zeitraum zwischen den evaluierten Zeitabschnitten wurde eine SOP „Blutkulturen“ in Zusammenarbeit mit dem Antibiotic-Stewardship(ABS)-Teams und der zentrale Notaufnahme entwickelt, implementiert und geschult. Ein positives Votum der Ethikkommission der Heinrich-Heine-Universität (2019-392-RetroDEuA) lag vor.Die pflegerischen und ärztlichen Mitarbeiter wurden zu 92 % bzw. 93 % geschult. Die Anzahl der abgenommenen Blutkulturen stieg von 1757 auf 2872 um 64 % ebenso wie die Anzahl der Blutkulturen/1000 Fälle von 287 auf 481 (68 %). Die Anzahl der positiven Blutkulturen reduzierte sich von 18,6 auf 13,7 % (p 0,05). Typische Hautkeime fanden sich in 34,4 % und 26,4 % der Fälle (p 0,05).Die durch Schulungen begleitete Einführung einer SOP „Blutkulturen“ in der zentralen Notaufnahme kann einen relevanten Beitrag zur antimikrobiellen Diagnostik leisten und sowohl die Quantität als auch die Qualität erhöhen.

Femoral neck fractures (FNF) are one of the most frequent fractures among elderly patients and commonly require surgical treatment. Bipolar hip hemiarthroplasty (BHHA) is mostly performed in these cases.In the present retrospective study geriatric patients with FNF (n = 100) treated either by anterior minimal-invasive surgery (AMIS; n = 50) or lateral conventional surgery (LCS; n = 50) were characterized (age at the time of surgery, sex, health status/ASA score, walking distance and need for walking aids before the injury) and intraoperative parameters (duration of surgery, blood loss, complications), as well as postoperative functional performance early (duration of in-patient stay, radiological leg length discrepancy, ability to full weight-bearing, mobilization with walking aids) and 12 months (radiological signs of sintering, clinical parameters, complication rate) after surgery were analyzed.Patients in the AMIS group demonstrated a reduced blood loss intraoperatively, while the duration of surgery and complication rates did not differ between the two groups. Further, more patients in the AMIS group achieved full weight-bearing of the injured leg and were able to walk with a rollator or less support during their in-patient stay. Of interest, patients in the AMIS group achieved this level of mobility earlier than those of the LCS group, although their walking distance before the acute injury was reduced. Moreover, patients of the AMIS group showed equal leg lengths postoperatively more often than patients of the LCS group. No significant differences in functional and surgery-related performance could be observed between AMIS and LCS group at 12 months postoperatively.In conclusion, geriatric patients treated by AMIS experience less surgery-related strain and recover faster in the early postoperative phase compared to LCS after displaced FNF. Hence, AMIS should be recommended for BHHA in these vulnerable patients.

Background/aim mmune checkpoint inhibition (CPI) has an increasing impact in the multimodal treatment of locally advanced non-small cell lung cancer (LA-NSCLC). Increasing evidence suggests treatment outcome depending on tumor cell PD-L1 expression. The purpose of this retrospective study was to investigate the prognostic value of PD-L1 expression on tumor cells in combination with CD8+ tumor stroma-infiltrating lymphocyte (TIL) density in inoperable LA-NSCLC treated with concurrent chemoradiotherapy (CRT). Patients and method We retrospectively assessed clinical characteristics and initial tumor biopsy samples of 31 inoperable LA-NSCLC patients treated with concurrent CRT. Prognostic impact of tumor cell PD-L1 expression (0% versus ≥1%) and CD8+ TIL density (0–40% vs. 41–100%) for local control, progression-free (PFS) and overall survival (OS) as well as correlations with clinicopathological features were evaluated. Results Median OS was 14 months (range: 3–167 months). The OS rates at 1- and 2 years were 68 and 20%. Local control of the entire cohort at 1 and 2 years were 74 and 61%. Median PFS, 1-year and 2-year PFS were 13 ± 1.4 months, 58 and 19%. PD-L1 expression neg/CD8low) and type IV (PD-L1pos/CD8low) tumors (median OS: 57 ± 37 vs. 10 ± 5 months, p = 0.05), respectively. Conclusion Assessment of PD-L1 expression on tumor cells in combination with CD8+ TIL density can be a predictive biomarker in patients with inoperable LA-NSCLC treated with concurrent CRT.

There are no officially approved therapies for metastatic pheochromocytomas apart from ultratrace 131I-metaiodbenzylguanidine therapy, which is approved only in the United States. We have, therefore, investigated the antitumor potential of molecular-targeted approaches in murine pheochromocytoma cell lines [monocyte chemoattractant protein (MPC)/monocyte chemoattractant protein/3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)], immortalized mouse chromaffin Sdhb−/− cells, three-dimensional pheochromocytoma tumor models (MPC/MTT spheroids), and human pheochromocytoma primary cultures. We identified the specific phosphatidylinositol-3-kinase α inhibitor BYL719 and the mammalian target of rapamycin inhibitor everolimus as the most effective combination in all models. Single treatment with clinically relevant doses of BYL719 and everolimus significantly decreased MPC/MTT and Sdhb−/− cell viability. A targeted combination of both inhibitors synergistically reduced MPC and Sdhb−/− cell viability and showed an additive effect on MTT cells. In MPC/MTT spheroids, treatment with clinically relevant doses of BYL719 alone or in combination with everolimus was highly effective, leading to a significant shrinkage or even a complete collapse of the spheroids. We confirmed the synergism of clinically relevant doses of BYL719 plus everolimus in human pheochromocytoma primary cultures of individual patient tumors with BYL719 attenuating everolimus-induced AKT activation. We have thus established a method to assess molecular-targeted therapies in human pheochromocytoma cultures and identified a highly effective combination therapy. Our data pave the way to customized combination therapy to target individual patient tumors.

Agricultural textiles are applied as a protective barrier against birds and insects, but also as ground covers against weeds and as protection from environmental factors. To protect plants from insects and other pests, pesticides and other protective agents are also used since a textile barrier is often insufficient or is not feasible. As these products have to be applied regularly, their use is costly and time-consuming. The situation also becomes more complicated when a textile is used to protect the field against other influences (e.g. frost). The application of pesticides and other protective agents in or on to the agricultural textile itself, enabling the active substances to be continuously released by the textile, is a viable alternative. Insecticides used in the agricultural sector pose an environmental problem, which cannot be solved even by incorporating them into textiles. A silica-based, ecological alternative will therefore be presented in this article.

Background In the last comprehensive review of the literature published in 2002, little information on the prevalence of orofacial clefts was available from low- and middle-income countries (LMICs). Objective To analyze published data on the birth prevalence of cleft lip and/or palate ( CL/P) from LMIC. Design Systematic review of the literature and meta-analysis of data from original papers on the birth prevalence of cleft lip and/or cleft palate (CL/P) in LMICs between 1990 and 2014. Secondary inclusion criteria were developed to analyze lower-quality studies from countries with scarce data. Main Outcome Measure Birth prevalence of undifferentiated CL/P (with or without associated syndrome or other anomaly). Results Twenty-eight studies met strict inclusion criteria. Among 31,475,278 total births, the pooled birth prevalence of undifferentiated CL/P was 1.38 per 1000 births (95% confidence interval [CI]: 1.20 to 1.56). Four studies met criteria for secondary analysis, providing data on 75,627 births, with a pooled prevalence of 0.75 CL/P cases per 1000 births (95% CI: 0.56 to 0.95). Comparison of studies was limited by variable definitions of cases and of the reference population and by inconsistent reporting of outcomes. There is significant heterogeneity in the findings. Conclusions In LMICs, approximately 1 in every 730 children is born with CL/P. To optimize comparability across settings, future research should use a standard classification system and standard criteria for data collection and presentation. As clefting is associated with deprivation, understanding the true scale, risks, and preventive measures for orofacial clefts in LMIC is a matter of both scientific and humanitarian importance.

The major goal of radiotherapy is the induction of tumor cell death. Additionally, radiotherapy can function as in situ cancer vaccination by exposing tumor antigens and providing adjuvants for anti-tumor immune priming. In this regard, the mode of tumor cell death and the repertoire of released damage-associated molecular patterns (DAMPs) are crucial. However, optimal dosing and fractionation of radiotherapy remain controversial. Here, we examined the initial steps of anti-tumor immune priming by different radiation regimens (20 Gy, 4 × 2 Gy, 2 Gy, 0 Gy) with cell lines of triple-negative breast cancer in vitro and in vivo. Previously, we have shown that especially high single doses (20 Gy) induce a delayed type of primary necrosis with characteristics of mitotic catastrophe and plasma membrane disintegration. Now, we provide evidence that protein DAMPs released by these dying cells stimulate sequential recruitment of neutrophils and monocytes in vivo. Key players in this regard appear to be endothelial cells revealing a distinct state of activation upon exposure to supernatants of irradiated tumor cells as characterized by high surface expression of adhesion molecules and production of a discrete cytokine/chemokine pattern. Furthermore, irradiated tumor cell-derived protein DAMPs enforced differentiation and maturation of dendritic cells as hallmarked by upregulation of co-stimulatory molecules and improved T cell-priming. Consistently, a recurring pattern was observed: The strongest effects were detected with 20 Gy-irradiated cells. Obviously, the initial steps of radiotherapy-induced anti-tumor immune priming are preferentially triggered by high single doses – at least in models of triple-negative breast cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a highly devastating disease with poor prognosis and rising incidence. Late detection and a particularly aggressive biology are the major challenges which determine therapeutic failure. In this review, we present the current status and the recent advances in PDAC treatment together with the biological and immunological hallmarks of this cancer entity. On this basis, we discuss new concepts combining distinct treatment modalities in order to improve therapeutic efficacy and clinical outcome – with a specific focus on protocols involving radio(chemo)therapeutic approaches.