Experimental validation of an inverse method for defect reconstruction in a two-dimensional waveguide model.

Defect reconstruction is essential in non-destructive testing and structural health monitoring with guided ultrasonic waves. This paper presents an algorithm for reconstructing notches in steel plates, which can be seen as artificial defects representing cracks by comparing measured results with those from a simulation model. The model contains a parameterized notch, and its geometrical parameters are to be reconstructed. While the algorithm is formulated and presented in a general notation, a special case of guided wave propagation is used to investigate one of the simplest possible simulation models that discretizes only the cross section of the steel plate. An efficient simulation model of the plate cross section is obtained by the semi-analytical scaled boundary finite element method. The reconstruction algorithm applied is gradient-based, and algorithmic differentiation calculates the gradient. The dedicated experimental setup excites nearly plane wave fronts propagating orthogonal to the notch. A scanning laser Doppler vibrometer records the velocity field at certain points on the plate surface as input to the reconstruction algorithm. Using two plates with notches of different depths, it is demonstrated that accurate geometry reconstruction is possible.

Detection of low numbers of bacterial cells in a pharmaceutical drug product using Raman spectroscopy and PLS-DA multivariate analysis.

Sterility testing is a laborious and slow process to detect contaminants present in drug products. Raman spectroscopy is a promising label-free tool to detect microorganisms and thus gaining relevance as a future alternative culture-free method for sterility testing in the pharmaceutical industry. However, reaching detection limits similar to standard procedures while keeping a high accuracy remains challenging, due to weak bacterial Raman signals. In this work, we show a new non-invasive approach focusing on detection of different bacteria in concentrations below 100 CFU per ml within drug product containers using Raman spectroscopy and multivariate data analysis. Even though Raman spectra from drug product with and without bacteria are similar, a partial least squared discriminant analysis (PLS-DA) model shows great performance to distinguish samples with bacterial contaminants in concentrations down to 10 CFU per ml. We used spiked samples with bacterial spores for model validation achieving a detection accuracy of 99%. Our results indicate the great potential of this rapid, and cost-effective approach to be used in quality control in the pharmaceutical industry.

Defect reconstruction in a two-dimensional semi-analytical waveguide model via derivative-based optimization.

This paper considers an indirect measurement approach to reconstruct a defect in a two-dimensional waveguide model for a non-destructive ultrasonic inspection via derivative-based optimization. The propagation of the mechanical waves is simulated by the scaled boundary finite element method that builds on a semi-analytical approach. The simulated data are then fitted to given data associated with the reflected waves from a defect which is to be reconstructed. For this purpose, we apply an iteratively regularized Gauss-Newton method in combination with algorithmic differentiation to provide the required derivative information accurately and efficiently. We present numerical results for three kinds of defects, namely, a crack, delamination, and corrosion. The objective function and the properties of the reconstruction method are investigated. The examples show that the parameterization of the defect can be reconstructed efficiently as well as robustly in the presence of noise.

[Summary of the S3 guideline on abdominal aortic aneurysm from an anesthesiological perspective]. / Zusammenfassung der S3-Leitlinie Bauchaortenaneurysma aus anästhesiologischer Sicht.

The current article is a summary of the 2018 revised S3 guideline on screening, diagnosis, therapy, and follow-up of the abdominal aortic aneurysm (AAA) from an anesthesiological point of view. It is the only interdisciplinary guideline that describes in particular the perioperative anesthesiological and intensive care management.

Correction: Safety and utility of image-guided research biopsies in relapsed high-grade serous ovarian carcinoma-experience of the BriTROC consortium.

This article was originally published under a CC BY NC SA License, but has now been made available under a CC BY 4.0 License.

Safety and utility of image-guided research biopsies in relapsed high-grade serous ovarian carcinoma-experience of the BriTROC consortium.

BACKGROUND: Investigating tumour evolution and acquired chemotherapy resistance requires analysis of sequential tumour material. We describe the feasibility of obtaining research biopsies in women with relapsed ovarian high-grade serous carcinoma (HGSC). METHODS: Women with relapsed ovarian HGSC underwent either image-guided biopsy or intra-operative biopsy during secondary debulking, and samples were fixed in methanol-based fixative. Tagged-amplicon sequencing was performed on biopsy DNA. RESULTS: We screened 519 patients in order to enrol 220. Two hundred and two patients underwent successful biopsy, 118 of which were image-guided. There were 22 study-related adverse events (AE) in the image-guided biopsies, all grades 1 and 2; pain was the commonest AE. There were pre-specified significant AE in 3/118 biopsies (2.5%). 87% biopsies were fit-for-purpose for genomic analyses. Median DNA yield was 2.87 µg, and was higher in biopsies utilising 14 G or 16 G needles compared to 18 G. TP53 mutations were identified in 94.4% patients. CONCLUSIONS: Obtaining tumour biopsies for research in relapsed HGSC is safe and feasible. Adverse events are rare. The large majority of biopsies yield sufficient DNA for genomic analyses-we recommend use of larger gauge needles and methanol fixation for such biopsies, as DNA yields are higher but with no increase in AEs.

Blending of reactive prepolymers to control the morphology and polarity of polyglycidol based microgels.

The compartmentalization of microgels is a challenging task for synthetic polymer chemistry. Although the complexation with low molecular weight compounds or the use of microfluidic techniques offer attractive possibilities for other length scales, it is difficult to implement compartments in the mesoscale range of 10-100 nm. Herein we show how simple blending of reactive prepolymers is suitable to design new microgel morphologies with tailored compartments. We use poly(EEGE)-block-poly(AGE) as crosslinkable, pro-hydrophilic prepolymer in blends with varying amounts of crosslinkable, yet hydrophobic poly(THF-stat-AllylEHO) or inert and hydrophobic polystyrene, and crosslink the allyl functional prepolymer(s) in a thiol-ene click-type reaction after miniemulsification. Our strategy shows how arrested versus free nanophase separation can be used to control easily the morphology and polarity of microgel particles.

[Need for information concerning medical rehabilitation of the federal german pension fund--findings of an online survey of general practitioners]. / Informationsbedarf zur medizinischen Rehabilitation der Deutschen Rentenversicherung--Ergebnisse eines Online-Surveys mit niedergelassenen Ärzten.

AIM: General practitioners complain about information deficits, uncertainties and unclear requirements associated with medical rehabilitation. In this study General practitioners' specific information needs are identified and the preferred form for the presentation of information is determined. METHODS: In a secondary analysis of several focus groups with different stakeholders, rehabilitation specific aspects were identified for which General practitioners could have further information needs. Those were transferred into an online-questionnaire. GPs in Schleswig-Holstein were invited to the online-survey via E-Mail by different medical associations. RESULTS: A total of 194 questionnaires were available for analysis. In general, high information needs covering all rehabilitation topics in the questionnaire are evident. The highest information need is recognised for the following aspects: in which cases it makes sense to file an objection, which measures have to take place before it makes sense to file an objection and what the term "ambulant measures have been exhausted" exactly means. GPs clearly prefer a website as a means of informational source. Under the option of multiple replies 74.2% prefer a website, followed by the option of a brochure (44.8%) and further education (22.2%). CONCLUSION: General practitioners have high information needs regarding different aspects of rehabilitation which are not satisfied with existing sources of information. The development of a user-friendly website with comprehensible information on the required aspects seems necessary to increase the acceptance and understanding of medical rehabilitation among practitioners and therefore to optimise rehabilitation processes.

[Different Health Impairments at the Beginning of Medical Rehab: Possibilities of more Flexibility using the Example of Rehab Aftercare]. / Unterschiedliche Ausgangsbelastungen in der medizinischen Rehabilitation: Möglichkeiten der Flexibilisierung am Beispiel der Reha-Nachsorge.

BACKGROUND: The aftercare-program new credo was developed interdisciplinary and with practical orientation for rehabilitation patients with chronic back pain. The concept focuses on rehabilitation aftercare from the beginning of rehabilitation treatment and includes a long-term support of rehabilitation patients after inpatient rehabilitation. A multi-center, controlled longitudinal study demonstrated that participants in the intervention group (IG) implemented significantly better rehabilitation contents and objectives in everyday life and had significant better long-term effects. Anyway, there are participants who don't benefit from the new credo as they begin rehabilitation treatment with low impairments. Assuming that rehabilitation patients with lower impairments need a less comprehensive rehabilitation aftercare compared to those with higher impairments, a follow-up study including a flexible aftercare strategy was conducted. Thereby it is investigated whether the IG achieves more sustainable effects despite of less aftercare compared to the control group (CG) without the aftercare program. METHOD: A prospective controlled longitudinal study in 2 rehabilitation clinics with 3 points of measurement was conducted. The flexibilization of the aftercare program was based on the level of impairment in the main outcome variable functional limitation in activities of daily living (FFbH-R) and restriction in participation (IMET) at the beginning of rehabilitation. Both questionnaires have been used in numerous studies successfully. Rehabilitation patients with low impairments received only the elements of the new credo during inpatient rehabilitation, rehabilitation patients with relevant impairments received the entire new credo over a period of 12 month after inpatient rehabilitation. The effects were evaluated with data from the CG of the primary study [Deck et al., 2012]. This sample was also divided according to their impairments. Rehabilitation patients with no relevant impairments were included in the analysis (IG N=81, KG N=157). RESULT: Regarding the long-term effects for the primary outcome variable FFbH-R a significant positive intragroup-effect was detected for the IG, the CG reached the initial value 12 month after inpatient rehabilitation. For the IMET a significant intragroup-effect is also visible in the IG, the CG does not change over the period of time. For both primary outcomes, there are no significant interaction effects to be observed. With respect to the secondary outcomes, in the IG significant small to moderate intragroup-effects were determined in all outcomes, the CG achieved for half of those outcomes significant small intragroup-effects. CONCLUSION: Rehabilitation patients, who begin rehabilitation with rather low impairments perpetuate their rehabilitation effects with an even reduced aftercare. Aftercare-programs should therefore be adapted to the individual needs. Rehabilitation patient, who start the rehabilitation with relative good health, seem not to have an added value from an intensive aftercare-program.

[Rehabilitation Application Rejected - What Happens Then?]. / Reha abgelehnt - und dann?

BACKGROUND: The German statutory pension insurance (Deutsche Rentenversicherung) rejects about a third of applications for medical rehabilitation. It is assumed that the health and occupational situation of people whose applications are rejected will become unsatisfactory. So far, there are no publications investigating the group of people with rejected applications. METHOD: Of 2 075 included applicants, 345 persons were rejected. Patients whose applications were rejected were matched with those whose applications were approved (Propensity-Score-Matching). At the end of the study, evaluable data sets including all 3 time points of measurement (application, 4 and 10 months thereafter) were available for 173 applicants with rejected applications and for 223 applicants approved for rehabilitation. The course of development of both groups was analysed using variance analysis with repeated measurements. The study was conducted for 27 months (January 2012-March 2014). RESULTS: At the time of application, there were no differences in health and occupational situation between the 2 groups. Also, there were no differences between groups in their utilization of outpatient therapies in the year before their application. 4 months later, a small advantage for those with an approved application was observed, and occasionally there were even significant differences. Both groups used medical and other healthcare offers comparably frequently. 10 months after application, both groups showed further improvements. There were no differences in the number of physician or non-physician patient consultations. DISCUSSION AND CONCLUSION: Our study could not confirm the assumption that the health or occupational situation of people with rejected application for rehabilitation suffers as a result of this rejection. Rather, the opposite seems to be the case. The factors that are responsible for the improvement, however, could not be identified by our study.

[Limitations of Social Participation in General Population - Normative Data of the IMET based on a Population-Based Survey in Northern Germany]. / Einschränkungen der Teilhabe in der Bevölkerung - Normdaten für den IMET auf der Basis eines Bevölkerungssurveys in Norddeutschland.

BACKGROUND: Medical rehabilitation in Germany is characterized by the biopsychosocial model of the ICF. Its complexity makes it less suitable for studies in rehabilitation sciences. For an implementation of the ICF, specific assessment instruments that are able to measure activity and participation efficiently in rehabilitation are needed. Instruments measuring social participation are rarely available in German language and have been employed only in a handful of empirical works. The "Index zur Messung von Einschränkungen der Teilhabe" (IMET) was developed in 2005 and measures participation of people with different chronic diseases as described in the ICF. The IMET has been applied in many studies in rehabilitation science, but as reference values were not available so far, the results could not be classified. METHOD: In a population survey, 5 004 residents in Luebeck were randomly selected by the registration office and sent a short questionnaire. The questionnaire contained questions on the overall state of health, quality of life, prevalence of chronic diseases and limitations of participation (IMET). RESULTS: The completed questionnaire was returned by 2 755 of 4 692 eligible people (58.7%). 731 residents declined participation. Therefore, the participation quota is 43.1%. The mean age of participants was 53 years (SD: 17.1), 53% were women.Limitations of participation varied according to sex and age. Men tended to be more limited in their participation. As expected, limitations in participation increased with age. Participants with a low level of education showed a significantly higher rate of participation restrictions than people with a higher level of education. The IMET correlated significantly with the health status and quality of life as well as with the prevalence of various chronic diseases. DISCUSSION: The random sample of Luebeck inhabitants comprised people between 19 and 79 years of age. The age distribution of our sample deviated from the German population with younger people being underrepresented, and older people being overrepresented. With respect to the educational level, the random sample of the Hanseatic city showed a larger proportion of people with higher education.In this population sample, there was a sex and age-related variation in restriction in participation and this correlated highly with content-related constructs. Norm values for the IMET enable classification of limitations of participation for people undergoing rehabilitation or patients suffering from chronic diseases.

[Position Paper: Perioperative Management of Adult Patients with Obstructive Sleep Apnea in ENT Surgery]. / Positionspapier zum perioperativen Management von erwachsenen Patienten mit obstruktiver Schlafapnoe bei HNO-ärztlichen Eingriffen.

Obstructive sleep apnea (OSA) is a common sleep-related breathing disorder with an increasing prevalence. Affected individuals suffer from a repetitive partial or complete occlusion of the pharyngeal airway despite continued respiratory efforts leading to sleep fragmentation, abnormal gas exchange and significant cardiovascular and metabolic morbidity. Surgical patients with OSA, which in the majority of cases has not been diagnosed prior to surgery, have an increased risk of developing a variety of pulmonary, cardiovascular and other complications throughout the perioperative period. Certain actions may contribute to increase the safety of patients with OSA during this time. Among them are preoperatively, a timely recognition and assessment of OSA and potentially co-existing diseases, intraoperatively, the selection of an appropriate anaesthesia and monitoring technique, and postoperatively, the continuation of monitoring for an adequate period of time with the option of intensive care treatment. The actual clinical approach should follow the risk profile of the individual patient which is determined by OSA severity, invasiveness of the surgical procedure and requirement for postoperative opioids as well as the incidence of critical events in the early postoperative period. Initiated and mandated by the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery, and conceived on the basis of the available literature and existing guidelines, the following paper provides recommendations for the perioperative management of adult patients with OSA in ENT surgery.

Prevalence of low back pain in adolescent athletes - an epidemiological investigation.

Low back pain (LBP) is a common symptom in the populations of western countries, and adolescent athletes seem to be prone to LBP. The main objective of this study was to analyze the point (LBP within the last 48 h), 1-year (LBP within the last 12 months) and lifetime (LBP within the entire life) prevalence rates of LBP in adolescent athletes participating in various sports. We also assessed the characteristics of LBP and its association with potential risk factors. To this end, 272 competitive adolescent athletes involved in 31 different sports (158 males, 113 females, 15.4 ± 2.0 years, body mass index [BMI] 20.3 ± 2.4 kg/m(2)) were enrolled in a 10-month prospective clinical trial that included a questionnaire and physical examination. We found a point prevalence of 14%, a 1-year prevalence of 57%, and a lifetime prevalence of 66% for LBP. The mean age of first appearance of LBP was 13.1 ± 2.0 years. The lifetime prevalence was significantly higher in volleyball than in biathletes (74.3 vs. 45.7%, p = 0.015). Our findings confirm that LBP is a common symptom in adolescent athletes; LBP prevalence correlates with sports participation and individual competitive level. Adolescent athletes with LBP should receive a thorough diagnostic work-up and adapt training and technique correspondingly when indicated.

Patupilone in patients with pretreated metastatic/locally recurrent colorectal cancer: results of the Phase II CINATRA trial.

BACKGROUND: Phase I trials of the microtubule stabilising agent patupilone showed encouraging tumour control and response rates in patients with metastatic colorectal cancer. METHODS: Patients with metastatic or locally recurrent colorectal cancer who had progressed following treatment with oxaliplatin, irinotecan and fluoropyrimidines were treated with patupilone (8 mg/m(2) IV every 3 weeks) in combination with dexamethasone or prednisolone. RESULTS: The trial was closed early after 29 patients had been enrolled due to concerns about toxicity. 20 patients (71.4 %) experienced at least one grade 3-5 toxicity, most commonly diarrhoea (14 patients), dehydration (7 patients) and lethargy (6 patients). The 12 week progression-free survival rate was 16.7 % (95 % CI 6.1 %-36.5 %) in the 24 patients with a 12 week scan available or who had died prior to the 12 week scan. No complete or partial responses were seen by 12 weeks. The median progression-free survival was 2.6 months (95 % CI 2.3-2.9) and median overall survival was 6.1 months (95 % CI 3.7-8.4). CONCLUSION: Patupilone given at a dose of 8 mg/m(2) IV over 20 min every 3 weeks was associated with high levels of toxicity and no significant evidence of efficacy in patients with pre-treated colorectal cancer.

Methysergide attenuates systemic burn edema in rats.

BACKGROUND: Thermal injuries of more than 20% total body surface area result in systemic shock with generalized edema. Burn shock is induced by a variety of mediators, mainly immunomodulative cytokines. Administration of methysergide (Met), a serotoninergic receptor blocking agent, reduces generalized edema in endotoxemia in rats. In this study we evaluated the systemic effects of Met after thermal injury. METHODS: Donor rats (DR [n=8]) for positive controls and study groups underwent thermal injury (100°C water, 30% TBSA (Total Burn Surface Area), 12s). Shamburn plasma was harvested after a shamburn procedure ([n=4], 37°C water, 30% TBSA, 12s). Plasma was harvested 4h posttrauma and was transferred to healthy individuals. Recipient animals were randomized in 3 groups (1: burnplasma, 2: shamburn, 3: burnplasma plus methysergide (Bolus of 1mg/kg body weight)). Intravital microscopy was performed in mesenteric venules (0/60/120min). Edema was assessed by FITC-albumin extravasation. Leukocyte sticking (cells/mm(2)) and microhemodynamic parameters were assessed. RESULTS: Significant systemic capillary leakage was observed after burnplasma-transfer. Edema formation was significantly lower in negative controls. Application of methysergide reduced FITC-efflux to baseline levels. Adherent leukocytes increased in all groups, at 120min the amount of adherent leukocytes in positive controls was significantly higher in comparison to shamburn, differences to MET-groups were not significant. CONCLUSION: Burnplasma transfer to healthy individuals induces leukocyte activation and plasma extravasation and this effect is reduced by administration of Met. This may be attributed to leukocyte dependent as well as independent mechanisms. Evaluation of more specific serotoninergic antagonists is required to distinguish between systemic and local effects.

Veno-venous extracorporeal membrane oxygenation (ECMO) support during anaesthesia for oesophagectomy.

The use of extracorporeal membrane oxygenation in adults has increased in popularity and importance for the support of patients with cardiac or pulmonary failure. Although it is now quite commonly used in the intensive care unit, its use has rarely been described as a means of support during anaesthesia and surgery. We report the case of a patient who required curative resection of the oesophagus following previous left pneumonectomy where veno-venous extracorporeal membrane oxygenation was required both during surgery and for the first three days postoperatively. We describe the anaesthetic management of this patient who only had a single lung, review other alternatives and discuss why extracorporeal membrane oxygenation was particularly suited to this case. To the best of our knowledge, the anaesthetic literature to date does not contain a case report of this type.

[Anesthesiological considerations for patients with trisomy 21 (Down syndrome)]. / Anästhesiologische Besonderheiten der Trisomie 21 (Down-Syndrom).

The most common chromosomal abnormality is trisomy 21 which is also known as Down syndrome and occurs in approximately 1 in 800 births. The majority of the resulting disabling conditions cannot be cured and affect people of all ages, ethnicity and economic levels. Life expectancy has increased with advances in medical care in the same way as in the rest of the population. One of the major tasks for health care professionals is to help these differently abled children and their families function in the most effective way possible as they learn to accept the limitations imposed by a persistent disability. Signs and symptoms of trisomy 21 are very variable based on the trias of mental retardation to a variable degree, hand anomalies and cardiac complications. Other abnormalities are atlantoaxial instability (AAI), tracheal stenosis, a predisposition to respiratory complications, chronic hypothyroidism, microgenia and macroglossia. These conditions are relevant to anesthetic procedures and patients with Down syndrome and their families have specific expectations and attitudes towards medical and anesthetic treatment.

Developing the skill of laryngeal mask insertion: prospective single center study.

BACKGROUND: Laryngeal mask insertion (LMI) represents a fundamental skill for anesthesiologists in routine management as well as in difficult airway situations. This study aimed to evaluate the time needed by first year anesthesiology residents to perform 40 LMIs and assessed the associated success rates and the number of attempts needed for successful LMI. METHODS: This prospective single center study evaluated the number of work days, the success rate and the attempts needed for successful LMI (LMA ProSeal™) in consecutive blocks of five LMI procedures and the related difficulties and complications. RESULTS: From 2007 to 2010 a total of 10 anesthesiology resident physicians were evaluated consecutively. These residents needed a mean of 18.3 ± 4.1 (mean ± standard deviation) working days to successfully perform 40 LMIs. The LMI success rate after the first 5 LMIs increased steadily up to the results after 40 LMIs per resident (LMI success rate within 1 attempt 72 versus 86 %, p = 0.09, LMI success rate within all LMI attempts 74 versus 96 %, p = 0.001). The mean number of attempts required until successful LMI decreased from 1.45 ± 0.82 after the first 5 LMIs to 1.16 ± 0.37 after 40 LMIs (p = 0.03). The most common difficulties associated with unsuccessful LMI by residents that led to handing over to an experienced colleague were small oral aperture (9.8 %), short thick neck, large tongue, blood/mucus in the mouth or throat (each 7.3 %) and retrognathy (4.9 %). CONCLUSIONS: The increasing LMI success rate and the decreasing rate of LMI attempts for successful airway management correlated to a learning curve and development of LMI dexterity over time.

Controlling fast transport of cold trapped ions.

We realize fast transport of ions in a segmented microstructured Paul trap. The ion is shuttled over a distance of more than 10(4) times its ground state wave function size during only five motional cycles of the trap (280 µm in 3.6 µs). Starting from a ground-state-cooled ion, we find an optimized transport such that the energy increase is as low as 0.10±0.01 motional quanta. In addition, we demonstrate that quantum information stored in a spin-motion entangled state is preserved throughout the transport. Shuttling operations are concatenated, as a proof-of-principle for the shuttling-based architecture to scalable ion trap quantum computing.

Developing the skill of endotracheal intubation: implication for emergency medicine.

BACKGROUND: Securing the airway by means of endotracheal intubation (ETI) represents a fundamental skill for anaesthesiologists in emergency situations. This study aimed to evaluate the time needed by first-year anaesthesiology residents to perform 200 ETIs and assessed the associated success rates and number of attempts until successful ETI. METHODS: This prospective single centre study evaluated the number of working days, the success rate, the attempts needed until successful ETI in consecutive blocks of 25 ETI procedures and the related difficulties and complications. RESULTS: From 2007 to 2010, 21 residents were evaluated consecutively. These residents needed a mean (mean ± standard deviation) of 15.6 ± 3.0 days for 25 ETIs. Out of all residents 52% reached the target value of 200 ETIs after 50.2 ± 14.8 weeks of total working time. The ETI success rate after the first 25 ETIs increased steadily to the results after 200 ETIs (ETI success rate within one ETI attempt: 67% vs. 83%, P = 0.0001; ETI success rate within all ETI attempts: 82% vs. 92%, P = 0.0001). The number of attempts required until successful ETI decreased from 1.6 ± 0.8 after the first 25 ETIs to 1.3 ± 0.6 after 200 ETIs (P = 0.0001). CONCLUSION: The increasing rate of relative ETI success and the decreasing rate of necessary attempts for successful airway management suggest a steadily increasing gain in ETI experience. The complications that developed during the first 200 ETI procedures justify supervision by a specialist in the field or a senior physician. Moreover, these results may influence the minimum requirement for qualification in anaesthesiology and emergency medicine.