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State-of-the-art manufacturing processes used in the electric drive production show a high degree of automation and provide a large amount of process data. Often these data remain unused even though they contain potentially valuable process information. The efficient processing and evaluation of these data bears enormous potential for improving the electric drives production, for example with regard to contacting processes. Innovative machine learning (ML) methods already proved to be a powerful tool for big data set evaluation and continuously enter the manufacturing domain. However, the comprehensive and feasible ML application in manufacturing is hindered by the large effort necessary for adequate data preparation. This work lays the foundation for ML application in ultrasonic metal welding and related contacting techniques, which play an important role in the electric drives production. Therefore, on the one hand side, a data pipeline is developed which covers necessary steps of data preparation. On the other hand side, two data sets generated with a validated US metal welding process model are processed with the data pipeline and quality prediction is performed with three different regression methods, which include classical linear regression as well as advanced ML methods as a neural network. For quality prediction, the mean absolute percentage error reaches values as low as 6.9 %.

Organic light-emitting diodes (OLEDs) currently suffer mostly from only moderate outcoupling efficiencies, calling for many different photonic strategies to increase the share of extracted photons. The quantification of concepts relying on scattering based on periodic or random structures proves complicated and often deserves more attention. To evaluate light extraction methods of OLEDs, we define a procedure leading to a quantifiable extraction efficiency η EE which can be calculated for top- or bottom-emitting OLEDs comprising external as well as internal outcoupling structures. Hence, the extraction efficiency allows to evaluate scattering approaches independently from the employed OLED system. A systematic study of 1D periodically corrugated red top-emitting OLEDs reveals the origin of a moderate enhancement due to an extraction efficiency of η EE = 14 %. Furthermore, our work provides recommendations how OLEDs with periodic corrugations should be characterized.

The spectral radiant intensity and external quantum efficiency of red top-emitting organic light emitting diodes with integrated one dimensional periodic gratings is studied in dependence of the cavity length with comparison to optical simulations.

Understanding the population dynamics of migratory animals and predicting the consequences of environmental change requires knowing how populations are spatially connected between different periods of the annual cycle. We used stable isotopes to examine patterns of migratory connectivity across the range of the western sandpiper Calidris mauri. First, we developed a winter isotope basemap from stable-hydrogen (δD), -carbon (δ13C), and -nitrogen (δ15N) isotopes of feathers grown in wintering areas. δD and δ15N values from wintering individuals varied with the latitude and longitude of capture location, while δ13C varied with longitude only. We then tested the ability of the basemap to assign known-origin individuals. Sixty percent of wintering individuals were correctly assigned to their region of origin out of seven possible regions. Finally, we estimated the winter origins of breeding and migrant individuals and compared the resulting empirical distribution against the distribution that would be expected based on patterns of winter relative abundance. For breeding birds, the distribution of winter origins differed from expected only among males in the Yukon-Kuskokwim (Y-K) Delta and Nome, Alaska. Males in the Y-K Delta originated overwhelmingly from western Mexico, while in Nome, there were fewer males from western North America and more from the Baja Peninsula than expected. An unexpectedly high proportion of migrants captured at a stopover site in the interior United States originated from eastern and southern wintering areas, while none originated from western North America. In general, we document substantial mixing between the breeding and wintering populations of both sexes, which will buffer the global population of western sandpipers from the effects of local habitat loss on both breeding and wintering grounds.

Many aquatic invertebrates alter their behaviour in response to chemical stimuli from predators. Less is known about how finely prey can discriminate between stimuli from predatory and related nonpredatory species, even in well-studied hermit crabs. We tested the time to emerge from the shell after disturbance (hiding time) of a common intertidal hermit crab. Pagurus granosimanus was exposed to effluent from two large-bodied brachyuran crabs: the durophagous, predatory red rock crab, Cancer productus, and the herbivorous kelp crab, Pugettia producta, in a controlled laboratory setting. Hiding times were a dramatic 41% shorter in the presence of Cancer effluent than when exposed to Pugettia effluent, which did not differ from a sea water control. Therefore hermit crabs can distinguish between chemical effluent from predatory and nonpredatory brachyuran crabs, which could include crab-specific compounds or metabolites from recently consumed prey, and adjust their behaviour accordingly. Shorter hiding times probably decrease the risk of being eaten by a shell-breaking predator because hermit crabs may be better able to elude them, either by running rapidly away or by abandoning their shell before it is crushed. Individual tests with three video stimuli (control, predatory crab, herbivorous crab), and combined tests with video and chemical stimuli, revealed a consistent generalized response to the presence of video but no differences among video treatments.

Objective Extracorporeal circulation is considered the gold standard in the treatment of hypothermic cardiocirculatory arrest; however, few centers use extracorporeal membrane oxygenation instead of standard extracorporeal circulation for this indication. The aim of this study was to evaluate whether extracorporeal membrane oxygenation-assisted resuscitation improves survival in patients with hypothermic cardiac arrest. Methods A consecutive series of 59 patients with accidental hypothermia in cardiocirculatory arrest between 1987 and 2006 were included. Thirty-four patients (57.6%) were resuscitated by standard extracorporeal circulation, and 25 patients (42.4%) were resuscitated by extracorporeal membrane oxygenation. Accidental hypothermia was caused by avalanche in 22 patients (37.3%), drowning in 22 patients (37.3%), exposure to cold in 8 patients (13.5%), and falling into a crevasse in 7 patients (11.9%). Multivariate logistic regression analysis was used to compare extracorporeal membrane oxygenation with extracorporeal circulation resuscitation, with adjustment for relevant parameters. Results Restoration of spontaneous circulation was achieved in 32 patients (54.2%). A total of 12 patients (20.3%) survived hypothermia. In the extracorporeal circulation group, 64% of the nonsurviving patients who underwent restoration of spontaneous circulation died of severe pulmonary edema, but none died in the extracorporeal membrane oxygenation group. In multivariate analysis, extracorporeal membrane oxygenation-assisted resuscitation showed a 6.6-fold higher chance for survival (relative risk: 6.6, 95% confidence interval: 1.2–49.3, P = .042). Asphyxia-related hypothermia (avalanche or drowning) was the most predictive adverse factor for survival (relative risk: 0.09, 95% confidence interval: 0.01–0.60, P = .013). Potassium and pH failed to show statistical significance in the multivariate analysis. Conclusions Extracorporeal rewarming with an extracorporeal membrane oxygenation system allows prolonged cardiorespiratory support after initial resuscitation. Our data indicate that prolonged extracorporeal membrane oxygenation support reduces the risk of intractable cardiorespiratory failure commonly observed after rewarming.

Objective: Mechanical circulatory support can maintain vital organ perfusion in patients with cardiac failure unresponsive to standard pharmacologic treatment. The purpose of the current study was to report complication and survival rates in patients supported with emergency percutaneous venoarterial cardiopulmonary bypass because of prolonged cardiogenic shock or cardiopulmonary arrest. Design: Retrospective clinical study. Subjects: A total of 46 patients supported with venoarterial cardiopulmonary bypass, 25 because of cardiogenic shock unresponsive to pharmacologic therapy and 21 because of cardiopulmonary arrest unresponsive to standard advanced cardiac life support. Results: In 41 of the 46 patients (89%), stable extracorporeal circulation was established; in five patients (11%), femoral cannulation was accomplished only after a surgical cutdown. A total of 28 patients were weaned from cardiopulmonary bypass (19 of 25 patients with cardiogenic shock vs. 9 of 21 patients with cardiopulmonary arrest, p = .03), and 13 patients had long-term survival (10 of 25 patients with cardiogenic shock vs. 3 of 21 patients with cardiopulmonary arrest, p = .1). Complications directly related to the use of cardiopulmonary bypass were found in 18 patients (39%), major complications related to femoral cannulation being the most common single cause for bypass-associated morbidity (eight patients, 17%) Conclusions: Long-term survival rates after emergency percutaneous cardiopulmonary bypass are encouraging in patients with an underlying cardiocirculatory disease amenable to immediate corrective intervention (angioplasty, surgery, transplantation).

Die kardiopulmonale Reanimation bei tiefer akzidenteller Hypothermie (Korperkerntemperatur

Objective: The aim of the current study was to assess the effects of epinephrine in a pig model of hypothermic cardiac arrest followed by closed-chest cardiopulmonary resuscitation combined with active rewarming, simulating the clinical management of an arrested hypothermic patient in a hospital without cardiopulmonary bypass facilities. Design: Prospective, randomized animal study. Setting: University research laboratory. Subjects: Twelve 12- to 16-week-old domestic pigs. Interventions: Pigs were surface cooled to a body core temperature of 28°C. After 4 min of untreated cardiac arrest, manual closed-chest CPR and thoracic lavage with 40°C warmed fluid were started. After 3 min of external chest compression animals were randomly assigned to receive epinephrine (45, 45 and 200 μg/kg) or saline placebo in 5-min intervals. Measurements and main results: Coronary perfusion pressure was about 15 mmHg in placebo group pigs. Coronary perfusion pressure was significantly higher after epinephrine, but restoration of spontaneous circulation was not more frequent (one of six epinephrine versus three of six saline placebo pigs, P =0.34). After 45 μg/kg epinephrine the arterial P o 2 was significantly lower when compared to the saline placebo. The third 200 μg/kg epinephrine dose resulted in a significantly enhanced mixed venous hypercarbic acidosis. Conclusions: After a short 4-min period of hypothermic cardiac arrest, epinephrine may not be necessary to maintain coronary perfusion pressure around the threshold usually correlating with successful defibrillation, even during prolonged closed-chest CPR combined with active rewarming. The enhanced mixed venous hypercarbic acidosis in epinephrine-treated animals may support the argument against repeated or high dose epinephrine administration during hypothermic CPR.

Objectives: To investigate effects of intravenous norepinephrine (NE) and phenylephrine (PE) on intestinal oxygen supply in an autoperfused, innervated jejunal segment. Design and setting: Prospective, randomized animal study in an animal research laboratory. Materials and methods: In 24 anesthetized and normoventilated pigs a segment of the jejunal mucosa was exposed by midline laparotomy and antimesenteric incision. Mucosal oxygen tension (PO2muc; Clark-type surface oxygen electrodes), microvascular hemoglobin oxygen saturation (HbO2, tissue reflectance spectrophotometry), and microvascular blood flow (perfusion units, PU; laser Doppler velocimetry), systemic hemodynamics, mesenteric-venous acid base and blood gas variables, and systemic acid base and blood gas variables were recorded after a resting period and at 20-min intervals during infusion of NE (0.01, 0.05, 0.1, 0.5, 1, 2 µg×kg–1×min–1; n=8) or PE (0.1, 0.5, 1, 2, 5, 10 µg×kg–1×min–1; n=8) and in controls (n=8) without treatment. Results: NE infusion led to significant tachycardia, an increase in cardiac output, and systemic oxygen delivery and consumption while PE progressively increased mean arterial pressure with only small effects on systemic blood flow. NE or PE infusion did not affect mesenteric venous oxygen tension (baseline: PE 53±5, NE, 52±4.2 mmHg), mesenteric oxygen extraction ratio (baseline: PE 0.29±0.08, NE 0.3±0.06), jejunal microvascular blood flow (baseline: PE 254±127, NE 282±72 PU), PO2muc (baseline: PE 31±9.1, NE 33±11 mmHg), and HbO2 (baseline: PE 52±9.6%, NE 58±11.6%). Conclusion: Despite major differences in systemic hemodynamics jejunal tissue oxygen supply is not affected by progressively increasing intravenous infusion of norepinephrine and phenylephrine.

OBJECTIVE To study the effects of increasing dosages of epinephrine given intravenously on intestinal oxygen supply and, in particular, mucosal tissue oxygen tension in an autoperfused, innervated jejunal segment. DESIGN Prospective, randomized experimental study. SETTING Animal research laboratory. SUBJECTS Domestic pigs. INTERVENTIONS Sixteen pigs were anesthetized, paralyzed, and normoventilated. A small segment of the jejunal mucosa was exposed by midline laparotomy and antimesenteric incision. Mucosal oxygen tension was measured by using Clark-type surface oxygen electrodes. Microvascular hemoglobin oxygen saturation and microvascular blood flow (perfusion units) were determined by tissue reflectance spectrophotometry and laser-Doppler velocimetry. Systemic hemodynamics, mesenteric-venous acid-base and blood gas variables, and systemic acid-base and blood gas variables were recorded. Measurements were performed after a resting period and at 20-min intervals during infusion of increasing dosages of epinephrine (n = 8; 0.01, 0.05, 0.1, 0.5, 1, and 2 microg x kg(-1) x min(-1)) or without treatment (n = 8). In addition, arterial and mesenteric-venous lactate concentrations were measured at baseline and at 60 and 120 mins. MEASUREMENTS AND MAIN RESULTS Epinephrine infusion led to significant tachycardia; an increase in cardiac output, systemic oxygen delivery, and oxygen consumption; and development of lactic acidosis. Epinephrine significantly increased jejunal microvascular blood flow (baseline, 267 +/- 39 perfusion units; maximum value, 443 +/- 35 perfusion units) and mucosal oxygen tension (baseline, 36 +/- 2.0 torr [4.79 +/- 0.27 kPa]; maximum value, 48 +/- 2.8 torr [6.39 +/- 0.37 kPa]) and increased hemoglobin oxygen saturation above baseline. Epinephrine increased mesenteric venous lactate concentration (baseline, 2.9 +/- 0.6 mmol x L(-1); maximum value, 5.5 +/- 0.2 mmol x L(-1)) without development of an arterial-mesenteric venous lactate concentration gradient. CONCLUSIONS Epinephrine increased jejunal microvascular blood flow and mucosal tissue oxygen supply at moderate to high dosages. Lactic acidosis that develops during infusion of increasing dosages of epinephrine is not related to development of gastrointestinal hypoxia.

Objective : To study reactive hyperemia (PH) using a transcutaneous PO2/PCO2 combination electrode heated to 37°C and tissue reflectance spectrophotometry in patients before and after cardiopulmonary bypass (CPB) to determine whether microcirculatory function of skin is altered. Design : Prospective study. Setting : Anesthesiology and critical care unit of a university hospital. Participants : Eight patients undergoing elective CPB under mild hypothermia. Interventions : To produce RH, blood flow to the forearm was prevented by inflation of a cuff to 300 mmHg for an interval of 5 minutes. Measurements and Main Results : Measurements were obtained on the day prior to surgery (DPS), on the day of surgery (DOS) rewarmed to 37°C in the intensive care unit (ICU), and on the first (POD 1) and the third postoperative days (POD 3). The following parameters were recorded: preocclusive baseline cutaneous PO2, and PCO2 (B-PtcO2, B-PtcCO2), and microvascular hemoglobin saturation (B-HbO2); postischemic peak of PtcO2, PtcCO2, and HbO2; and 10 minutes after release of the cuff occlusion posthyperemic PtcO2, PtcCO2, and HbO2. B-PtcO2 was 3.5 ± 1.2 mmHg, on DPS, 2.6 ± 0.7 mmHg on DOS, 1.5 ± 0.3 mmHg on POD 1, and 3.5 ± 3.5 mmHg on POD 3. B-PtcCO2 increased significantly from 40.1 ± 2.5 mmHg to 52.2 ± 2.0 mmHg on DOS (p = 0.01) and to 48.9 ± 3.6 mmHg on POD 1 (p = 0.02). On POD 3, B-PtcCO2 was 40.6 ± 2.6 mmHg. B-HbO2 declined from a preoperative value of 42.4% ± 8.6% to 37.1% ± 14.7% on DOS and further to 21.7% ± 4.8% on POD 1, which was significantly different (p = 0.03). On POD 3, B-HbO2 still remained lower (30.7% ± 6.2%) compared with the preoperative value. RH (ΔPtcO2, ΔHBO2) was quantified as the differences between peak PtcO2, HBO2 and B-PtcO2, B-HBO2. ΔPtcO2 was 13.0 ± 2.3 on DPS, 11.3 ± 2.9 on DOS, 12.6 ± 2.6 on POD 1, and 11.5 ± 3.5 on POD 3. ΔHBO2 was 42.0 ± 5.6 on DPS, 40.0 ± 7.1 on DOS, 49.9 ± 2.5 on POD 1, and 52.9 ± 6.4 on POD 3. The elimination rate of carbon dioxide from skin (ECO2) was calculated as difference between peak PtcCO2 and PtcCO2 after 3 minutes of reperfusion divided by the difference between peak PtcCO2 and B-PtcCO2. ECO2 was 1.0 ± 0.2 kPa/min on DPS, 0.7 ± 0.1 kPa/min on DOS, and 0.8 ± 0.1 kPa/min on POD 1 and POD 3. Conclusion : Cutaneous microcirculation assessed by RH is well preserved during the immediate postoperative period in patients undergoing uncomplicated coronary artery surgery with CPB.

Objectives: Cannulation and clamping of a severely atherosclerotic ascending aorta during coronary artery bypass grafting (CABG) can lead to cerebral embolization of atheromatous debris and should therefore be avoided whenever possible. A variety of surgical techniques including performance of extraanatomical coronary bypass conduits has been described to solve this problem. We report on a preliminary series of four patients in whom the axillary artery was used as an inflow vessel for venous coronary artery bypass grafts which were performed on the beating heart in order to achieve an aortic no touch concept. Methods: The axillary artery was exposed between the pectoralis major muscle and the deltoid muscle via an infraclavicular incision. A saphenous vein graft of at least 40 cm in length was sutured to the axillary artery and then brought into the pericardial cavity following an intercostal and transpleural route. The graft was anastomosed to the target vessel using local coronary occlusion. The procedure was carried out via sternotomy in three patients who also received additional internal mammary artery in situ grafts for adequate coronary revascularization. In one high risk patient an isolated axillocoronary bypass was performed in a minimally invasive fashion via anterolateral minithoracotomy. Results: The procedure was completed without major technical difficulties in all four patients. The mean graft length required was 33:2 ^ 1:6 cm, postoperative ultrasonic duplex scans of the axillocoronary grafts revealed a mean flow of 62:5 ^ 23:6 ml/min. No stroke or brachial plexus injury occurred. Three patients are in angina class I (Canadian Cardiovascular Society Classification), one patient is in class II postoperatively. After a mean follow-up of 11.5 ^ 6.6 months postoperatively all grafts remain patent. Conclusion: Axillocoronary bypass grafting can be easily performed for management of the untouchable ascending aorta. Straightforward surgical technique and the accessibility to noninvasive diagnostics seem to offer advantages over other extraanatomical bypass grafts. q 1999 Elsevier Science B.V. All rights reserved.

Objective : To evaluate the effects of dopamine- 1-receptor stimulation on intestinal mucosal tissue oxygenation. Design : Prospective, experimental, controlled trial. Setting : Animal research laboratory. Subjects : Anesthetized domestic pigs (30 to 45 kg). Interventions : A small segment of the jejunal mucosa and serosa was exposed by midline laparotomy and antimesenteric incision. Fenoldopam, a selective dopamine-1-receptor agonist, was infused in steps, exponentially increasing from 0.6 to 9.6 μg/kg/min via a central venous catheter (n = 8, fenoldopam group), whereas a second group (n = 6, saline group) was only given the solvent. Measurements and Main Results : Systemic hemodynamics as well as systemic and jejunal acid base and blood gas variables were measured using an arterial catheter, a thermodilution pulmonary artery catheter, and a jejunal venous catheter. Jejunal mucosal and serosal tissue Po 2 were measured by means of Clark-type surface oxygen electrodes. Oxygen saturation and relative concentration of mucosal microvascular hemoglobin were measured by means of tissue reflectance spectrophotometry. In the fenoldopam group, systemic oxygen delivery (12.5 ± 0.8 mL/kg/min at baseline) increased by 56% (p

Beobachtung und Bildungsdokumentation haben in zahlreiche deutsche Bildungsplane Einzug gehalten und gehoren zu zentralen Inhalten von Ausbildungsplanen der padagogischen Fachkrafte. So wird z.B. im Orientierungsplan fur Bildung und Erziehung im Elementarbereich niedersachsischer Tageseinrichtungen fur Kinder erklart: „Die Beobachtung ist in jedem Fall eine zentrale Aufgabe der padagogischen Fachkrafte und ein unerlassliches Instrument der Bildungsbegleitung von Kindern“ (Niedersachsisches Kultusministerium 2005, S. 39).

Mutation testing was developed to measure the adequacy of a test suite by seeding artificial bugs (mutations) into a program, and checking whether the test suite detects them. An undetected mutation either indicates a insufficiency in the test suite and provides means for improvement, or it is an equivalent mutation that cannot be detected because it does not change the program's semantics. Impact metrics-that quantify the difference between a run of the original and the mutated version of a program-are one way to detectnon-equivalent mutants. In this paper we present a genetic algorithm that aims to produce a set of mutations that have a high impact, are not detected by the test suite, and at the same time are well spread all over the code. We believe that such a set is useful for improving a test suite, as a high impact of a mutation implies it caused a grave damage, which is not detected by the test suite, and that the mutation is likely to be non-equivalent. First results are promising: The number of undetected mutants in a set of evolved mutants increases from 20 to over 70 percent, the average impact of these undetected mutants grows at the same time by a factor of 5.

[WCl4(Ph-C≡C-I)(THF)] has been prepared by the reaction of trans-[WCl4(SEt2)2] with Ph - C≡C - I in THF solution, whereas [WCl4(Ph-C≡C-Te-nC4H9)(THF)] has been synthesized by the reaction of Ph-C≡C-Te-nC4H9 with tungsten hexacloride in the presence of C2Cl4 and THF. Both complexes were characterized by IR spectroscopy and by crystal structure determinations. [WCl4(Ph-C≡C-I)(THF)]: Space group P21/c, Z = 4, 2617 observed unique reflections, R = 0.064. Lattice dimensions at –70°C: a = 1518.2(3), b = 714.5(1), c = 1540.0(3) pm, β = 90.09(3)°. [WCl4(Ph-C≡C-Te–nC4H9)(THF)]. Space group P1̄, Z = 2, 3911 observed unique reflections, R = 0.067. Lattice dimensions at 20°C: a = 844.0(3), b = 974.6(4), c = 1002.4(3) pm, α = 76.00(4), β= 105.14(1), γ = 82.03(3)°. Both complexes have molecular structures, in which the tungsten atoms are seven-coordi-nate by four chlorine ligands, by the two alkyne carbon atoms, and in trans position to the latter by the oxygen atom of the THF molecule. The WC bond lengths are 198 and 200(1) in the telluro complex and 206 and 196(1) pm in the iodine derivative.