Third international challenge to model the medium- to long-range transport of radioxenon to four Comprehensive Nuclear-Test-Ban Treaty monitoring stations

In 2015 and 2016, atmospheric transport modeling challenges were conducted in the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification, however, with a more limited scope with respect to emission inventories, simulation period and number of relevant samples (i.e., those above the Minimum Detectable Concentration (MDC)) involved. Therefore, a more comprehensive atmospheric transport modeling challenge was organized in 2019. Stack release data of Xe-133 were provided by the Institut National des Radioéléments/IRE (Belgium) and the Canadian Nuclear Laboratories/CNL (Canada) and accounted for in the simulations over a three (mandatory) or six (optional) months period. Best estimate emissions of additional facilities (radiopharmaceutical production and nuclear research facilities, commercial reactors or relevant research reactors) of the Northern Hemisphere were included as well. Model results were compared with observed atmospheric activity concentrations at four International Monitoring System (IMS) stations located in Europe and North America with overall considerable influence of IRE and/or CNL emissions for evaluation of the participants' runs. Participants were prompted to work with controlled and harmonized model set-ups to make runs more comparable, but also to increase diversity. It was found that using the stack emissions of IRE and CNL with daily resolution does not lead to better results than disaggregating annual emissions of these two facilities taken from the literature if an overall score for all stations covering all valid observed samples is considered. A moderate benefit of roughly 10% is visible in statistical scores for samples influenced by IRE and/or CNL to at least 50% and there can be considerable benefit for individual samples. Effects of transport errors, not properly characterized remaining emitters and long IMS sampling times (12-24 h) undoubtedly are in contrast to and reduce the benefit of high-quality IRE and CNL stack data. Complementary best estimates for remaining emitters push the scores up by 18% compared to just considering IRE and CNL emissions alone. Despite the efforts undertaken the full multi-model ensemble built is highly redundant. An ensemble based on a few arbitrary runs is sufficient to model the Xe-133 background at the stations investigated. The effective ensemble size is below five. An optimized ensemble at each station has on average slightly higher skill compared to the full ensemble. However, the improvement (maximum of 20% and minimum of 3% in RMSE) in skill is likely being too small for being exploited for an independent period.

Hemodynamic Properties of the Hemopump HP14

Background

The Hemopump HP14 is a catheter-mounted, transvalvular, left ventricular assist device intended for femoral percutaneous insertion. The pump was developed for patients with postoperative or postinterventional low cardiac output and for CABG surgery on the beating heart. Little is known about the effect of afterload and hematocrit on the pump performance.

Methods

The influence of hematocrit and afterload on the pump flow was tested using an in vitro model filled with heparinized bovine blood. Regression analysis of the pump flow with respect to three hematocrit values (20%, 30%, 40%) and ten afterload levels (30 mmHg-120 mmHg in 10 mmHg increments) was performed for all pump speed levels (n = 7).

Results

At all pump speed levels reduction of afterload and hematocrit were significant predictors for increasing pump flow (p<0.001). For hematocrit values between 40% and 20% and highest pump speed, mean pump flow at lowest afterload ranged between 2.34 and 2.53 L/min; and at highest afterload between 1.31 and 1.53 L/min. For speed level 1, afterload of 120 mmHg and hematocrit of 40% there was a maximal retrograde flow of 230 ± 35 ml/min.

Conclusions

Pump performance is significantly improved by both afterload and hematocrit reduction. In the weaning phase and during the removal of the device, the pump should run at a speed level of at least three to prevent retrograde flow in the pump. Estimates for pump flow in vivo can be extrapolated from our diagrams. Our results show that the Hemopump HP14 is a valuable alternative to intra-aortic balloon counterpulsation.

Banking and Distribution of Large Cryopreserved Arterial Homografts in Brussels: Assessment of 4 Years of Activity by the European Homograft Bank (EHB) with Reference to Implantation Results in Reconstruction of Infected Infrarenal Arterial Prostheses and Mycotic Aneurysms

In 1991 European Homograft Bank (EHB) initiated a program of cryopreservation and distribution of large arteries to meet a new demand for quality-controlled arterial homo grafts of various sizes. From May 1991 to June 1995, 308 arteries have been registered from 136 donors: 122 brain death cases and 14 cadavers (mean age 34 years, male/female ratio 1.52/1); 263 arteries were cryopreserved (113 aortas, 64 aortic bifur cations, and 86 femoral); 19 were discarded for atherosclerosis (6.7%); 10 batches of arteries were partially or totally discarded because of persistent contamination and further eight batches for positive or doubtful viral serology. One hundred patients were treated in nine European centers with one (N = 69) or more EHB homografts. Indications were: infected prosthesis 70 (17 with aortoenteric fistula); mycotic aneurysm 19 (four ascending aortas, two with bronchial fistula); neoplastic infiltration of subrenal aorta one; extracardiac reconstructions/shunts 10. (continued on next page) (Abstract continued) Results from homograft reconstructions in infected prosthesis or mycotic aneurysm were available in 90 patients. There were 19 early deaths and 24 early complications, three were directly graft-related and included a fatal case of homograft rupture. Sixty- seven vascular cases were followed up from 1 month onward (mean: 16 months): 50 were uneventful; there were nine late deaths, of which two resulted from graft-related digestive hemorrhage; there were eight cases of late complications; three arteries were partly explanted as a result of focal thrombosis. Four patients were lost to follow-up. In the cases of aortoenteric fistula, however, the results were disappointing with only five late survivors of the 16 treated patients. Finally, these results show that cryopreserved arteries seem to perform as well in the midterm as the fresh ones.

Both the banking activity of cryopreserved homografts and the short- to mid-term performances of the implants in cases of prosthetic or native arterial infection are very satisfactory, provided no aortoenteric fistula is present. Cryopreserved arteries can also be used for extracardiac shunts and reconstructions.

Double crush syndrome of the median nerve revealing a primary non-Hodgkin's lymphoma of the flexor digitorum superficialis muscle

Extranodal manifestations of lymphoma are well described in the literature and occur in 20 to 30% of patients. Skeletal muscle involvement is rare. We describe the case of a patient with non-Hodgkin's lymphoma in a forearm muscle. At the age of 86, the featured patient started experiencing continuous, progressive and high intensity pain that was more frequent at night and localized in the right dominant hand. It was associated with paresthesia and hypoesthesia, primarily in the thumb, index finger and middle finger. Clinical examination and electrodiagnosis led to the diagnosis of carpal tunnel syndrome. The patient underwent carpal tunnel release at a private hand center. The progression was unfavorable. Additional clinical examination and electrodiagnosis showed compression of the anterior interosseous nerve (double crush syndrome). The patient was referred to our university hand center for further management. Magnetic resonance imaging showed a large mass of about 20cm occupying the entire anterior compartment of the forearm and enclosing the median nerve. Biopsies were performed and revealed a diffuse large B-cell primary non-Hodgkin's lymphoma. The patient underwent chemotherapy and radiotherapy. Six months later, the patient was in complete remission. Muscular involvement during lymphoma is rare. Biopsy is mandatory; needless radical surgery can be avoided because lymphoma is primarily a non-surgical disease. The key points of the treatment process are reviewed.

[Prefabrication of transplants in plastic surgery]

Complex three-dimensional defects with destruction of the external form, loss of functional stability and inner lining are associated with tactical and technical challenges in reconstructive plastic surgery. Causative factors are mutilating infections, resection of malignant tumors and trauma, predominantly located at the aerodigestive junction, the urogenital region and the extremities. Three-dimensional tissue constructions are preformed distant to the defect site allowing safe pedicled or microsurgical transfer into the defect.

[Cardiac rehabilitation, a proven intervention underutilized in the French-speaking part of Switzerland]

Cardiac rehabilitation is associated with a reduced risk of recurrence and mortality after an acute coronary syndrome. Cardiac rehabilitation is a multidisciplinary approach which starts during the acute hospital phase, then followed by a four to six weeks home-based or stationary program, in order to maintain long-term lifestyle changes. Despite the important health benefits of cardiac rehabilitation and its cost-effectiveness, only half of the patients in Europe will achieve a cardiovascular prevention program after an acute coronary syndrome. In the French part of Switzerland, one explanation for this low adherence might be the lack of both stationary and home-based program facilities.

[Cardiac MR in development: the large multicenter CMR studies in 2012]

The results of several large multicenter CMR studies were reported in 2012, thus, constantly corroborating the evidence on CMR performance. In this review, we present results of the MR-IMPACT programme and the CE-MARC study, which demonstrated the superiority of perfusion-CMR over gated SPECT for the workup of suspected CAD, the currently available data from the European CMR registry, comprising almost 30,000 patients from 57 participating centers in 15 European countries, and finally, the results of the Advisa-MRI study, which documented the safety of a MRI-compatible pacemaker system. These large trials and others set the basis for the recommendations in the new European guidelines on heart failure to use CMR as a first line method if echocardiographic quality is inadequate or the etiology of heart failure is unclear.

Presence of gapped silicene-derived band in the prototypical (3 × 3) silicene phase on silver (111) surfaces

By mapping the low-energy electronic dynamics using angle resolved photoemission spectroscopy (ARPES), we have shed light on essential electronic characteristics of the (3 × 3) silicene phase on Ag(111) surfaces. In particular, our results show a silicene-derived band with a clear gap and linear energy-momentum dispersion near the Fermi level at the Γ symmetry point of the (3 × 3) phase at several distinctive Brillouin zones. Moreover, we have confirmed that the large buckling of ~0.7 Å of this silicene structure induces the opening of a gap close to the Fermi level higher than at least 0.3 eV, in agreement with recent reported photoemission results. The two-dimensional character of the charge carriers has also been revealed by the photon energy invariance of the gapped silicene band, suggesting a limited silicene-silver hybridization, in disagreement with recent density-functional theory (DFT) predictions.

[Adults with congenital heart diseases: a growing population, a multidisciplinary approach]

Untill recently, congenital heart disease was considered as a childhood's disease. With improvement in pediatric survival, adults with a congenital heart disease (ACHD) represent an emerging group of patients who need specialized medical care. In 2010, the ESC published newguidelines on global and specific management of adults with congenital heart disease. ACHD centers organize appropriate medical care for these patients, promote specialist training and national scientific research in collaboration with other national ACHD centers.

[Percutaneous closure of left atrial appendage: a new hope for patients with atrial fibrillation?]

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The risk of thromboembolic events is important, and at that time, there is no definite treatment for AF. Oral anticoagulation also represents a hemorrhagic risk factor. Ninety percent of atrial thrombi are located within the left atrial appendage. The percutaneous closure of this left atrial appendage with a device has been shown to decrease thromboembolic events even after interruption of oral anticoagulation as compared to warfarin in a recent randomized study. Recent data support this innovative technique as a reasonable alternative to long term anticoagulation in patients at high risk of bleeding.

Quo vadis? - Monitoring Campylobacter in Germany

Campylobacter is a poorly recognized foodborne pathogen, leading the statistics of bacterially caused human diarrhoea in Europe during the last years. In this review, we present qualitative and quantitative German data obtained in the framework of specific monitoring programs and from routine surveillance. These also comprise recent data on antimicrobial resistances of food isolates. Due to the considerable reduction of in vitro growth capabilities of stressed bacteria, there is a clear discrepancy between the detection limit of Campylobacter by cultivation and its infection potential. Moreover, antimicrobial resistances of Campylobacter isolates established during fattening of livestock are alarming, since they constitute an additional threat to human health. The European Food Safety Authority (EFSA) discusses the establishment of a quantitative limit for Campylobacter contamination of broiler carcasses in order to achieve an appropriate level of protection for consumers. Currently, a considerable amount of German broiler carcasses would not comply with this future criterion. We recommend Campylobacter reduction strategies to be focussed on the prevention of fecal contamination during slaughter. Decontamination is only a sparse option, since the reduction efficiency is low and its success depends on the initial contamination concentration.

[Examination of the opportunity costs and turnover situation in patients with deep sternal infections]

BACKGROUND

Each and every hospital of any kind is forced, due to increased cost pressure, to work as economically and as efficiently as possible. This even applies when the operational orientations of the hospitals institutions are different. In the present article an analysis of the repercussions of the treatment of postoperative complications in terms of entrepreneurial practice is given. Our focus is on the opportunity cost.

METHOD

A theoretical calculation of opportunity costs is made based on the example of postoperative infections following cardiac surgery and the resulting treatment. The bases of the examinations are the results collected at the hospital Mediclin Herzentrum Lahr / Baden in 2008. The wound healing disorders were recorded from November 2004 until November 2007 and include 3675 patients who were operated on using a median sternotomy. Out of the 3675 patients 45 (1.2 %) were affected. Various treatment options are at hand. The used therapy algorithm in our practice is dependent on the stage and the development of the infection.

RESULTS

If the high trim point, the medial trim point and the low trim point of the mediastinitis patients, as well as the average revenue and the surcharge omission on exceeding the high trim point (these data can be found in the annual accounts) and knowledge of the actual length of stay of the mediastinitis patient are known, the opportunity cost, respectively potential turnover increases, can be calculated. Reducing the medial trim point from 48.43 to, for example, 36.37 days could potentially produce a turnover increase of as much as 10 633.41 €.

CONCLUSION

Keeping patient safety in mind, significant turnover increases can be achieved with adequate planning. The considered sales situation, however, can only be achieved under the same terms: these being free operating room and bed capacities, available personnel, equal cost of materials as well as enough patients. The consideration of opportunity costs could be important for entrepreneurs if staff shortage continues and, in economical terms, non-expendable capacities are created.

[Cardiac MRI in the follow-up of adult congenital cardiomyopathy patients]

Magnetic resonance imaging is a rapidly developing modality in cardiology. It offers an excellent image definition and a large field of view, allowing a more accurate morphological assessment of cardiac malformations. Due to its unique versatility and its ability to provide myocardial tissue characterization, cardiac magnetic resonance (CMR) is now recognized as a central imaging modality for a wide range of congenital heart diseases, including assessment of post-surgical cardiac anatomy, quantification of valvular disease and detection of myocardial ischemia. CMR provides useful diagnostic information without any radiation exposure, and improves the global management of patients with congenital heart disease.

[Selection and preoperative follow-up of heart transplantation candidates in the French part of Switzerland]

Heart transplantation (HTx) started in 1987 at two university hospitals (CHUV, HUG) in the western part of Switzerland, with 223 HTx performed at the CHUV until December 2010. Between 1987 and 2003, 106 HTx were realized at the HUG resulting in a total of 329 HTx in the western part of Switzerland. After the relocation of organ transplantation activity in the western part of Switzerland in 2003, the surgical part and the early postoperative care of HTx remained limited to the CHUV. However, every other HTx activity are pursued at the two university hospitals (CHUV, HUG). This article summarizes the actual protocols for selection and pre-transplant follow-up of HTx candidates in the western part of Switzerland, permitting a uniform structure of pretransplant follow-up in the western part of Switzerland.

[Cardiology]

The present review provides a selected choice of clinical research in the field of interventional cardiology, electrophysiology and cardiac imaging. We also focused on the new guidelines published by the European society of cardiology in 2010 (revascularization, atrial fibrillation and device therapy in heart failure).

[Preoperative cardiac assessment before non-cardiac surgery: cardiac risk stratification]

Perioperative cardiac events occurring in patients undergoing non-cardiac surgery are a common cause of morbidity and mortality. Current guidelines recommend an individualized approach to preoperative cardiac risk stratification prior to non-cardiac surgery, integrating risk factors both for the patient (active cardiac conditions, clinical risk factors, functional capacity) and for the planned surgery. Preoperative cardiac investigations are currently limited to high-risk patients in whom they may contribute to modify the perioperative management. A multidisciplinary approach to such patients, integrating the general practitioner, is recommended in order to define an individualized peri-operative strategy.

[Pre-operative cardiac assessment in non-cardiac surgery: a frequent dilemma simplified by a decision tree]

In patients undergoing non-cardiac surgery, cardiac events are the most common cause of perioperative morbidity and mortality. It is often difficult to choose adequate cardiologic examinations before surgery. This paper, inspired by the guidelines of the European and American societies of cardiology (ESC, AHA, ACC), discusses the place of standard ECG, echocardiography, treadmill or bicycle ergometer and pharmacological stress testing in preoperative evaluations. The role of coronary angiography and prophylactic revascularization will also be discussed. Finally, we provide a decision tree which will be helpful to both general practitioners and specialists.

[Cardiac involvement in connective tissue disease: the example of systemic lupus erythematosus]

When we think of cardiac affection in the context of systemic lupus erythematosus (SLE), we usually refer to pericarditis first. As frequent as this affection is, it is actually not the only cardio-vascular problem that occurs with this systemic inflammatory disease. Are the cardiac events--ranging from multiple heart valve involvements to increased cardiovascular risks--clinically significant? And are they involving a specific follow-up, treatment or support? We are therefore trying to evaluate these questions in order to give some recommendations to any practitioners following up a lupus patient, or a patient suffering from any other inflammatory systemic disease.

[Cardiology 2009: what is new?]

The present review provides a selected choice of clinical research in the field of heart failure, electrophysiology, cardiac imaging and interventional cardiology.

A model of chronic lung allograft rejection in the rat

Bronchiolitis obliterans, the pathological hallmark of chronic pulmonary rejection, severely impacts long-term survival following lung transplantation. However, experimental reproduction of this pathophysiological phenomenon has not been achieved with contemporary in vivo models. Here, a model of chronic rejection is described, with sensitised recipients receiving unilateral orthotopic rat lung transplants. Lewis rats, sensitised with skin from brown Norway rats 7 days before receiving left lung transplants from donors that were Lewis x brown Norway F(1) hybrids, were analysed during day 21-84. The development of chronic rejection was modulated by a treatment with rapamycin and cyclosporin, and characterised histologically, immunohistochemically and by reverse transcriptase PCR. Characteristic histopathological changes leading to chronic rejection were induced over time by an initial treatment with cyclosporin in the presence of continuous rapamycin application. At day 84, fibrotic lesions replaced the respiratory epithelium within small bronchioles, with strong expression of smooth muscle alpha-actin and upregulation of mRNA for T-helper cell type-1 cytokines, smooth muscle alpha-actin, transforming growth factor-beta and CC chemokine ligand 5, but decreased forkhead box protein P3 gene expression. A reproducible and clinically relevant experimental set-up for progressive chronic rejection in rat pulmonary allografts is described. This model will permit better understanding of the pathological changes of small airways during the development of bronchiolitis obliterans, and may serve as an in vivo set-up for testing the efficacy of novel therapeutic interventions.

[Indications for urgent coronary angiography. Part II: Acute coronary syndromes without ST-segment elevation]

The optimal treatment strategy for patients presenting with an acute coronary syndrome without ST elevation is controversial and different therapeutic approaches are recognized. Currently, given the literature available, it is not possible to recommend a universal systematic invasive approach. It is essential to individually risk stratify patients in order to identify those high risk patients that have been shown to benefit from an invasive strategy. Compared to conservative medical treatment, patients at low risk have not been shown to benefit from an invasive strategy. Urgent coronary angiography remains recommended for those patients with persistent or recurrent ischemic symptoms under optimal medical treatment.

[Monitoring and adjustment of immunosuppression after heart transplantation]

Heart transplantation remains the best therapeutic option for the treatment of end-stage heart failure. However, good survival rates can be obtained only if patients are closely monitored, particularly for their immunosuppressive regimens. Currently, a triple-drug regimen usually based on calcineurin-inhibitors (cyclosporin A or tacrolimus), anti-proliferative agents and steroids is used in most recipients. New agents such as the mTOR inhibitors, a more recently developed class of immunosuppressive drugs, can also be used in some patients. The aim of this article is to review currently used immunosuppressive regimens after heart transplantation, and to propose some individualized options depending on specific patient characteristics and recent pharmacological developments in the field.

[Indications for urgent coronary angiography. Part I: ST-segment elevation acute coronary syndromes]

The indications for urgent coronary angiography are stated in the guidelines for treatment of acute coronary syndromes. An invasive approach is considered the treatment of choice for patients presenting with ST elevation myocardial infarction within 12 hours of the beginning of symptoms. In the absence of contraindication, intravenous thrombolysis continues to be a valuable alternative to primary angioplasty within 3 hours of the beginning of clinical symptoms. Urgent coronary angiography continues to be recommended following the failure of thrombolysis, persistent myocardial ischemia after 12 hours of symptoms, recurrent myocardial ischemia following myocardial infarction or in the case of cardiogenic shock.

Intravenous thrombolytic treatment for acute myocardial infarction. Effects of early intervention and early examination

Intravenous thrombolytic treatment (streptokinase or anisoylated plasminogen streptokinase activator complex (APSAC) was given to 50 consecutive patients within 3 hours after onset of symptoms of acute myocardial infarction. Left heart catheterisation with coronary angiography and simultaneous double view left ventriculography were performed approximately 4 hours after start of thrombolytic treatment. This examination showed that the acute infarct-related coronary artery was open in 36 patients (72%) and closed in 14 patients (28%). A higher left ventricular ejection fraction was found among patients with open, than among patients with closed infarct-related artery (58.8% vs. 48.4%, p = 0.05). The group with open artery also had a lower score of regional left ventricular dysfunction (1.7 vs. 2.4, p less than 0.05, on a scale from 0-3). Single, double and triple vessel coronary heart disease was found in 22, 14 and 13 patients respectively. Mean age was lower in the group with single vessel disease as compared to double and triple vessel disease (48.4 years vs. 53.4 and 55.4 years, p less than 0.05 and p less than 0.005). Independently of whether the infarct-related artery was open or closed, there tended to be an inverse correlation between number of diseased vessels and preservation of left ventricular function (statistical significance only for single vessel versus triple vessel disease with respect to score of regional left ventricular dysfunction, 1.8 vs. 2.4, p less than 0.05). These findings suggest that early thrombolytic treatment within 3 hours of onset of symptoms may preserve myocardial tissue during the evolution of acute infarction. Furthermore, a presumably better collateralisation from adjacent coronary arteries without stenoses may be important for myocardial preservation. Finally, early angiographic examination can be performed safely and is a good support for determination of further treatment, which in the actual patients was coronary bypass surgery in 8 cases, transluminal angioplasty, PTCA, in 20 cases, and medical treatment alone in 22 cases.