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QuestionSoil seed banks (SSB), i.e., pools of viable seeds in the soil and its surface, play a crucial role in plant biology and ecology. Information on seed persistence in soil is of great importance for fundamental and applied research, yet compiling datasets on this trait still requires enormous efforts. We asked whether the machine learning (ML) approach could be used to infer and predict SSB properties of a regional flora based on easily available data.LocationEighteen calcareous grasslands located along an elevational gradient of almost 2000 m in the Bavarian Alps, Germany.MethodsWe compared a commonly used ML model (random forest) with a conventional model (linear regression model) as to their ability to predict SSB presence/absence and density using empirical data on SSB characteristics (environmental, seed traits and phylogenetic predictors). Further, we identified the most important determinants of seed persistence in soil for predicting qualitative and quantitative SSB characteristics using the ML approach.ResultsWe demonstrated that the ML model predicts SSB characteristics significantly better than the linear regression model. A single set of predictors (either environment, or seed traits, or phylogenetic eigenvectors) was sufficient for the ML model to achieve high performance in predicting SSB characteristics. Importantly, we established that a few widely available SSB predictors can achieve high predictive power in the ML approach, suggesting a high flexibility of the developed approach for use in various study systems.ConclusionsOur study provides a novel methodological approach that combines empirical knowledge on the determinants of SSB characteristics with a modern, flexible statistical approach based on ML. It clearly demonstrates that ML can be developed into a key tool to facilitate labor-intensive, costly and time-consuming functional trait research.

It has long been anticipated that relating functional traits to species demography would be a cornerstone for achieving large-scale predictability of ecological systems. If such a relationship existed, species demography could be modeled only by measuring functional traits, transforming our ability to predict states and dynamics of species-rich communities with process-based community models. Here, we introduce a new method that links empirical functional traits with the demographic parameters of a process-based model by calibrating a transfer function through inverse modeling. As a case study, we parameterize a modified Lotka–Volterra model of a high-diversity mountain grassland with static plant community and functional trait data only. The calibrated trait–demography relationships are amenable to ecological interpretation, and lead to species abundances that fit well to the observed community structure. We conclude that our new method offers a general solution to bridge the divide between trait data and process-based models in species-rich ecosystems. Advances in process-based community ecology models are hindered by the challenge of linking functional traits to demography in species-rich systems, where a high number of parameters need to be estimated from limited data. Here the authors propose a new Bayesian framework to calibrate community models via functional traits, and validate it in a species-rich plant community.

Active high-lift aircraft need exceptional aerodynamic control performance to operate at low airspeed. In this study a new concept for the improvement of controllability is investigated, incorporating the special capabilities of a blown Coanda flap system. The blowing system along the flaps is divided into twelve independently controllable segments. This provides the opportunity to influence the lift distribution along the wingspan by individual blowing performance settings for each segment without changing the flap deflection. This offers the chance to control the airplane in the final approach phase with fully deflected flaps by using only the blowing system and to dedicate specific control tasks to particular segments. A model for the blowing system influence on the local wing aerodynamics is implemented in an existing nonlinear full aircraft flight mechanics model. The system capabilities in terms of roll control and the climb performance are investigated by criteria evaluation and dynamic simulation assessment. The ability to fly turn/altitude change maneuvers by utilizing the active high-lift system is proven and a corresponding control concept is presented. It also includes the compensation of different blowing failure cases, which leads to acceptable but still improvable aircraft reactions.

Ecologists have long suspected that species are more likely to interact if their traits match in a particular way. For example, a pollination interaction may be more likely if the proportions of a bee's tongue fit a plant's flower shape. Empirical estimates of the importance of trait-matching for determining species interactions, however, vary significantly among different types of ecological networks. Here, we show that ambiguity among empirical trait-matching studies may have arisen at least in parts from using overly simple statistical models. Using simulated and real data, we contrast conventional generalized linear models (GLM) with more flexible Machine Learning (ML) models (Random Forest, Boosted Regression Trees, Deep Neural Networks, Convolutional Neural Networks, Support Vector Machines, naive Bayes, and k-Nearest-Neighbor), testing their ability to predict species interactions based on traits, and infer trait combinations causally responsible for species interactions. We find that the best ML models can successfully predict species interactions in plant-pollinator networks, outperforming GLMs by a substantial margin. Our results also demonstrate that ML models can better identify the causally responsible trait-matching combinations than GLMs. In two case studies, the best ML models successfully predicted species interactions in a global plant-pollinator database and inferred ecologically plausible trait-matching rules for a plant-hummingbird network, without any prior assumptions. We conclude that flexible ML models offer many advantages over traditional regression models for understanding interaction networks. We anticipate that these results extrapolate to other ecological network types. More generally, our results highlight the potential of machine learning and artificial intelligence for inference in ecology, beyond standard tasks such as image or pattern recognition., 48 pages, 5 figures

To report the efficacy of a new percutaneous technique for extraction of embolized catheters, five female patients (62±14 years) referred to our institution were analyzed. With the combination of a large-diameter steerable sheath with a sizeable snare system, three dislodged Port-A-Cath tubes and two ventriculoatrial shunts were retrieved successfully. Mean procedure time was 51±23 min, biplane fluoroscopy time was 22±21 min, and dose area product was 1188±992 dGy cm 2 . Percutaneous extraction of embolized venous catheters is highly effective with the help of this novel, self-assembled system. The presented technique provides major advantages with respect to three-dimensional steerability and should be considered for complex cases.

AIMS: Comorbidities pose a major challenge to screening, selection and follow-up of transcatheter aortic valve implantation (TAVI) patients as well as to the procedure itself. The aim of the present study was to assess cardiac and non-cardiac readmission rates besides clinical endpoint data in the first 50 patients of a single center TAVI programme. METHODS AND RESULTS: TAVI was performed using the transfemoral CoreValve system. Procedural success rate was 94%; intraprocedural mortality was 2%. 82% of the patients remained free of a combined safety endpoint at 30 days, and 76.1% remained free of a combined efficacy endpoint at six months (modified criteria of the Valve Academic Research Consortium). At six months, among all surviving patients, 10.3% had experienced readmissions for cardiac causes, and 43.6% had experienced readmissions for non-cardiac causes. Causes of non-cardiac readmissions showed a wide distribution over various medical disciplines, reflecting the high rate of comorbidities. Beyond six months until a predefined reference date (mean follow up 9.9 months), the probability of hospitalization fell by half (1.54 vs. 0.74 hospital days per patient per month), driven by a decrease of non-cardiac readmissions. Karnofsky score before and after TAVI yielded a significant and sustained improvement of performance status, as assessed retrospectively at reference date. CONCLUSION: The findings of the present study suggest that the high prevalence of comorbidities in high-risk TAVI patients results in a high rate of non-cardiac rehospitalizations during the first 6 months of follow-up. Despite this fact, improvement of global everyday performance following TAVI as perceived by the patients seems to be substantial.

ANAMNESE UND KLINISCHER BEFUND: Ein 29-jahriger, bisher gesunder Mann kam nach einem primar unkomplizierten gastroenteritischen Infekt wegen akuter Myalgien mit hochfebrilen Temperaturen zur stationaren Aufnahme. Innerhalb von 24 Stunden entwickelte sich ein lebensbedrohliches Zustandsbild mit einem katecholeminpflichtigen hamodynamischen Schockzustand und einer therapierefraktaren anhaltenden ventrikularen Tachykardie. UNTERSUCHUNGEN: Echo- und elektrokardiographische sowie laborchemische Befunde waren vereinbar mit einer fulminanten Myokarditis und einer akuten Myositis. Serologisch und bakteriologisch wurde in der Folge eine akute Infektion mit Salmonellen der Gruppe D nachgewiesen. THERAPIE UND VERLAUF: Unter konservativer supportiver Therapie kam es innerhalb von wenigen Tagen zu einer Konsolidierung des Zustandsbildes. Abgesehen von einem – histologisch gesicherten – Myositisrezidiv nach vier Wochen blieb der weitere Verlauf unkompliziert und es zeigte sich sowohl klinisch als auch echokardiographisch eine vollstandige funktionelle Remission. Dreieinhalb Jahre spater verstarb der Patient plotzlich. Histologisch fand sich eine umschriebene narbige Myokardfibrose. SCHLUSSFOLGERUNGEN: Eine fulminante Myokarditis stellt im Akutstadium eine lebenbedrohliche Erkrankung dar, die Prognose nach Ausheilung gilt aber als gut. In dem von uns dargestellten Fall sprechen viele Indizien fur einen Plotzlichen Herztod als Spatkomplikation einer fulminanten Myokarditis bakterieller Genese.

INTRODUCTION: The metabolic syndrome is a matter of immense public concern for atherosclerosis prevention. Key features are visceral obesity, dyslipidemia, hyperglycemia in the non-diabetic range, and arterial hypertension. Subclinical atherosclerosis is the clinical consequence of metabolic syndrome, which may influence the QT interval. The aim was to investigate the rate corrected QT interval in subjects with metabolic syndrome in comparison to those without cardiometabolic risk factor clusters, and to explore gender differences in cardiac repolarization between the two groups. PATIENTS, MATERIALS AND METHODS: Heart rate and QT interval were automatically measured from surface ECG in 1086 participants (767 men, 319 women) from the Salzburg-Atherosclerosis-Prevention-program-in-subjects-at-High-Individual-Risk (SAPHIR). To omit the QT adjustment bias inherent in Bazett's formula we used a QT adjustment method with linear scaling as described by Rautaharju. RESULTS: The prevalence of metabolic syndrome was 13.8% among males and 10% among females. Mean rate adjusted QT (QTa) intervals were longer in women than in men. Presence of metabolic syndrome, however, was associated with significantly prolonged QTa only in men but not in women. Adjustment for relevant confounders reduced the difference of mean QTa in men from 9.24 to 5.83 ms (95% CI 0.9–10.8), but this difference was still statistically significant (p = 0.021). The effect of metabolic syndrome on QTa was only partly mediated by hypertension and insulin resistance. In females, however, no relevant differences were detected for QTa interval between subjects categorized by presence or absence of metabolic syndrome. CONCLUSIONS: The findings indicate a significant association between metabolic syndrome and rate-invariant QT in middle-aged men after adjustment for other risk factors. QT measurement may provide additive diagnostic and prognostic information in populations undergoing cardiovascular risk screening. However, the effect of metabolic and hormonal factors on ventricular repolarization seems to differ between the sexes.

Objective: The purpose of the study was to test the dose-effect relationship of adenosine for the diagnosis of dual atrioventricular (AV) nodal physiology in patients presenting with supraventricular tachycardia. Subjects and Methods: The study population consisted of 57 patients (mean age 50 ± 14 years; 36 females, 21 males) with palpitations related to supraventricular tachycardia. Adenosine was injected as bolus during sinus rhythm at rest in order to unmask dual AV nodal physiology by a PR jump on surface ECG (defined as a sudden increase by ≧50 ms measured from the onset of the P-wave to the R-wave between two consecutive sinus beats). According to a stepwise clinical approach, adenosine was administered as bolus in incremental dosages (6 mg followed by 12 mg, if necessary up to 18 mg). Once a PR jump ≧50 ms or a high-grade AV block was noted on surface ECG, the injection was stopped at that dose. Results: A significant PR jump was noted after injection of 6 mg (n = 21, 99 ± 30 ms) or 12 mg (n = 13, 94 ± 35 ms), but not after 18 mg (n = 4, 35 ± 10 ms) adenosine. Provocation of temporary first-grade AV block (n = 13) was associated with the longest increment of PR interval, whereas high-grade AV block (n = 36) produced a significantly shorter PR jump (105 ± 35 vs. 65 ± 40 ms, p = 0.0024). Electrophysiological study and ablation were performed in 37 highly symptomatic patients. AV nodal reentrant tachycardia was diagnosed in 33 patients and orthodromic AV reentrant tachycardia in 4 patients. Conclusion: The adenosine test was characterized by a reverse dose-effect relationship as far as identification of AV nodal duality was concerned.

Various imaging techniques are nowadays in clinical use to obtain important information about pulmonary vein (PV) anatomy in patients undergoing catheter ablation of atrial fibrillation (AF). Although some controversy exists about the optimal approach for catheter ablation of AF in recent times, knowledge of the individual left atrial-PV anatomy remains a basic feature of the different ablational techniques. Angiographic delineation of PV ostia has become an integral part of the PV isolation procedure, mainly in order to avoid potentially harmful PV stenosis. Selective venography with angiocatheters is well documented and widely available but has its own limitations, particularly with respect to visualization of the atriovenous junctions. The present report summarizes the usefulness, safety and feasibility of a new angiographic technique for simultaneous imaging of ipsilateral PVs applicable during catheter ablation of AF. Electrophysiologically guided segmental PV isolation was accomplished in 31 patients mostly with paroxysmal atrial fibrillation, who experienced significant clinical improvement during a followup of 17 +/- 15 months. The angiographic technique was effective for assessment of the individual anatomy including common ostia and supernumerary veins which can be easily missed by selective venography. Variant PV ostia were identified in about 20% of patients; particularly the presence of a left common trunk was challenging for the segmental ablation strategy. Angiographic detection of variant PV anatomy was comparable to visualization with computer tomography performed at 4-months follow-up. Finally, this type of angiographic imaging performed at the time of catheter ablation may help to reduce the risk of significant PV stenosis.

Background: Atrial arrhythmias are frequently observed in patients with heart failure and may be a primary cause for decompensation during cardiac resynchronization therapy (CRT). The accurate detection of organized atrial tachyarrhythmias poses a challenge to the function of mode-switching biventricular pacemakers/defibrillators. Methods: The purpose of the study was to determine retrospectively the incidence of blanked atrial flutter and mode switch failure (2:1 lock-in), and to look for factors predisposing to this problem. A total number of 65 patients with CRT devices has been followed regularly over 18 ± 12 months. Five patients were excluded because of chronic atrial fibrillation and reprogramming to VVIR mode. Results: Seven out of 60 patients (12%) were diagnosed with blanked atrial flutter at unscheduled device interrogation. Sustained biventricular pacing at a median rate of 125/min—mimicking sinus tachycardia—resulted in rapid deterioration of heart failure and hospitalization. Mode switch failure occurred due to coincidence of every second flutter wave with atrial blanking. The group with 2:1 lock-in was programmed to longer atrial blanking times (143 ± 34 ms vs 105 ± 32 ms; P = 0.026) and AV intervals (126 ± 8 ms vs 107 ± 29; P = 0.001) than the group without lock-in. Other clinical characteristics examined did not differ between the two groups apart from a previous history of atrial fibrillation (P = 0.032). Conclusion: Blanked atrial flutter with rapid ventricular pacing is a clinically important problem in heart failure patients treated with CRT devices. Efforts should be made to avoid this complication by atrial lead implantation without ventricular farfield oversensing, by programming short PVAB and AV intervals, and by implementation of dedicated device algorithms.

In severely injured lower extremities with loss of the anterior compartment, the free functional rectus femoris musculocutaneous flap was used to restore extension of the foot and in soft-tissue reconstruction. From June 2000-July 2002, 3 patients were treated with this technique. Mean follow-up of the 3 patients was 27 months. Electromyography and the Stanmore system (recording pain, need for orthosis, ability to wear normal shoes, activity level, muscle power, active extension of the foot, and foot posture) were used to assess results of functional rectus femoris transfer. One patient had an excellent result, one patient had a good result, and one patient had a poor result, as assessed by the Stanmore system. Free functional rectus femoris transfer can obtain excellent results in treating foot-drop and soft-tissue defects due to lower leg compartment syndrome and loss of all muscles of the anterior compartment. (c)

Background: Newer glucose meters are easier to use, but direct comparisons with older instruments are lacking. We wished to compare analytical performances of four new and four previous generation meters.Methods: On average, 248 glucose measurements were performed with two of each brand of meter on capillary blood samples from diabetic patients attending our outpatient clinic. Two to three different lots of strips were used. All measurements were performed by one experienced technician, using blood from the same sample for the meters and the comparison method (Beckman Analyzer 2). Results were evaluated by analysis of clinical relevance using the percentage of values within a maximum deviation of 5% from the reference value, by the method of residuals, by error grid analysis, and by the CVs for measurements in series.Results: Altogether, 1987 blood glucose values were obtained with meters compared with the reference values. By error grid analysis, the newer devices gave more accurate results without significant differences within the group (zone A, 98–98.5%). Except for the One Touch II (zone A, 98.5%), the other older devices were less exact (zone A, 87–92.5%), which was also true for all other evaluation procedures.Conclusions: New generation blood glucose meters are not only smaller and more aesthetically appealing but are more accurate compared with previous generation devices except the One Touch II. The performance of the newer meters improved but did not meet the goals of the latest American Diabetes Association recommendations in the hands of an experienced operator.

We report a rare case of a 75-year-old hemiplegic man with a chronic pleural infection, a bronchopleural fistula, and a full-thickness defect of the chest. In one operation we performed open-window thoracostomy and pleural decortication as well as reconstruction of the chest defect and reclosure of the bronchopleural fistula with a latissimus dorsi muscle flap. The patient made a good recovery and was sent for rehabilitation in good condition. Surgical treatment was essential to control and ultimately halt the septic process. Use of a muscle transplant in a hemiplegic patient did not reduce mobility.

The J wave is a deflection that appears on the surface ECG as a late delta wave following the QRS complex. Also known as an Osborn wave, the J wave has been observed in various conditions and diseases. Our case highlights the typical electrocardiographic manifestations of hypothermia including the J deflection and ST segment elevation during atrial fibrillation. Thorough knowledge of these findings is important for prompt diagnosis and treatment of hypothermic states.

Syncope is a complex clinical syndrome that may be challenging with respect to a definite diagnosis. The implantable loop recorder (ILR) is a useful tool to define but also to exclude an arrhythmic aetiology.To investigate the causes of recurrent syncope or near-syncope with respect to underlying arrhythmias in non-selected consecutive patients monitored with an ILR.A retrospective study was conducted including 55 patients (34 men, 21 women; age 60+/-19 years) with unexplained syncope who received an ILR for prolonged monitoring at our institution between April 1998 and October 2006.Forty (73%) patients had a recurrence of syncope or near-syncope. Structural heart disease was present in 18 (33%) patients, 4 of them having an ejection fraction35%. An arrhythmia was detected as the cause of syncope in 25 (46%) patients. The ILR was successful in establishing a symptom-rhythm correlation in 63%. The mean follow-up period from implantation to occurrence of the detected arrhythmias was 9+/-8 months. Bradyarrhythmias were recorded in 12 (22%) patients, whereas tachyarrhythmias were found in 13 (24%) patients. Narrow QRS tachycardia was the underlying arrhythmia in 6 patients and wide QRS tachycardia in 7 patients. A pacemaker was implanted in all 12 patients with bradyarrhythmias. Implantable cardioverter defibrillator (ICD) therapy was indicated in 6 patients with adjunctive catheter ablation in 3 of them. Four patients presenting with paroxysmal supraventricular tachycardia were treated with radiofrequency catheter ablation.The ILR helped efficaciously to determine the correct diagnosis and appropriate treatment of recurrent syncope. A considerably high proportion of tachyarrhythmias was detected in this non-selected consecutive population. The majority of patients with tachyarrhythmic syncope required defibrillator implantation and/or radiofrequency ablation.

A previously healthy 29-year-old male was hospitalized due to acute myalgia and high temperature following an uncomplicated gastroenteritis. Within 24 hours, he developed life-threatening hemodynamic shock with the need for inotropic support and sustained ventricular tachycardia.Echocardiography and electrocardiogram as well as lab tests were consistent with the diagnosis of fulminant myocarditis and acute myositis. Serological and bacteriological analysis yielded an acute infection with salmonella D.The patient's condition stabilized under conservative supportive care within a few days. Apart from a histologically confirmed recurrent myositis four weeks later, no further complications occurred and the patient was clinically and echocardiographically considered to be in complete functional remission. Three and a half years later, however, the patient unexpectedly and suddenly died.Although fulminant myocarditis is a life-threatening condition in its initial phase, the prognosis after recovery is considered to be good. However, this case study suggests that sudden cardiac death as a late complication of fulminant myocarditis may occur.

To evaluate risk factors related to total mortality in an unselected population of patients implanted with a cardioverter defibrillator.Survival analysis was performed retrospectively investigating the records of 77 consecutive patients implanted with defibrillators (median 67 years, range 38-83 years; 63 men). All patients were followed regularly in 3-month intervals. The cause of mortality was assessed clinically, including post-mortem examination of device to assess possible arrhythmogenic death. Predictors were assessed by Kaplan-Meier analysis with log-rank tests and by Cox regression analysis (proportional hazards).Defibrillator recipients had a mean (+/-standard deviation) ejection fraction of 34+/-13%, left ventricular end-diastolic dimension (LVEDD) of 6.24+/-0.8 cm, QRS duration of 129+/-34 ms, and body mass index (BMI) of 26.4+/-4.3 kg/m(2). Atrial fibrillation was present in 32 patients, paroxysmal fibrillation in 23, and permanent fibrillation in 9 patients. The estimate of mean survival time for all patients was 51.5 (95% confidence interval 46.6-56.5) months. During the study period 11/77 (14%) patients died. Mean follow-up time was 24.5 months (range 0.2-60.7) for survivors and 7.6 months (range 1.5-42) for non-survivors. Independent predictors of mortality were the NYHA class (P=0.004), BMIor =26 kg/m(2) (P=0.024), presence of paroxysmal or permanent atrial fibrillation (P=0.014), and absence of arterial hypertension (P=0.010). LVEDD showed a weak significant effect on survival (P=0.049).Patients with implantable cardioverter defibrillator and a normal to lower BMI or atrial fibrillation had a significantly higher overall mortality. These factors may be indicative of end stage heart failure or diseases associated with high sympathetic activation.

Focal ablation of trigger premature ventricular complexes (PVCs) from the Purkinje system helped to suppress idiopathic ventricular fibrillation (VF) in an athlete who had suffered from frequent appropriate shock therapies. However, only a few days after successful ablation T-wave oversensing occurred during exercise and resulted in repetitive distressing defibrillator shocks. Despite lack of any changes on the surface ECG, the endocardially recorded electrogram revealed an unfavorable ratio of R-to-T-wave amplitude predisposing to double counting with accelerated heart rates. This case illustrates that T-wave oversensing may complicate the clinical course after successful ablation of malignant Purkinje ectopy.

In severely injured lower extremities with loss of the anterior compartment, the free functional rectus femoris musculocutaneous flap was used to restore extension of the foot and in soft-tissue reconstruction. From June 2000-July 2002, 3 patients were treated with this technique. Mean follow-up of the 3 patients was 27 months. Electromyography and the Stanmore system (recording pain, need for orthosis, ability to wear normal shoes, activity level, muscle power, active extension of the foot, and foot posture) were used to assess results of functional rectus femoris transfer. One patient had an excellent result, one patient had a good result, and one patient had a poor result, as assessed by the Stanmore system. Free functional rectus femoris transfer can obtain excellent results in treating foot-drop and soft-tissue defects due to lower leg compartment syndrome and loss of all muscles of the anterior compartment. (c)

Supraventricular Tachycardia with VA Conduction Block. We report the case of a 64-year-old patient with paroxysmal supraventricular tachycardia and persistent VA block. Induction and maintenance of tachycardia occurred without apparent activation of the atria. Diagnostic characteristics were most compatible with AV nodal reentrant tachycardia (AVNRT). Automatic junctional tachycardia and orthodromic nodoventricular or nodofascicular reentry tachycardia were considered in the differential diagnosis. Upper common pathway block during AVNRT may be explained by either intra-atrial conduction block or purely intranodal confined AVNRT. The arrhythmia was cured by a typical posteroseptal ablation approach guided by slow pathway potentials.