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This paper is concerned with computing global optimal solutions for maximum k-cut problems. We improve on the SBC algorithm of Ghaddar, Anjos and Liers in order to compute such solutions in less time. We extend the design principles of the successful BiqMac solver for maximum 2-cut to the general maximum k-cut problem. As part of this extension, we investigate different ways of choosing variables for branching. We also study the impact of the separation of clique inequalities within this new framework and observe that it frequently reduces the number of subproblems considerably. Our computational results suggest that the proposed approach achieves a drastic speedup in comparison to SBC, especially when k=3. We also made a comparison with the orbitopal fixing approach of Kaibel, Peinhardt and Pfetsch. The results suggest that, while their performance is better for sparse instances and larger values of k, our proposed approach is superior for smaller k and for dense instances of medium size. Furthermore, we used CPLEX for solving the ILP formulation underlying the orbitopal fixing algorithm and conclude that especially on dense instances the new algorithm outperforms CPLEX by far.

Psychotherapie beeinflusst nicht nur die Psyche, sondern auch das Gehirn, wie Studien zeigten. Dieses Kapitel fokussiert auf den Zusammenhang zwischen Psychotherapie und Gehirn und wie wir diesen besser erforschen konnen, um die Psychotherapie effektiver zu gestalten.

Objective To provide an update to the “Surviving Sepsis Campaign Guidelines for Management of Severe Sepsis and Septic Shock,” last published in 2008. Design A consensus committee of 68 international experts representing 30 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict of interest policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independent of any industry funding. A stand-alone meeting was held for all subgroup heads, co- and vice-chairs, and selected individuals. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development. Methods The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence from high (A) to very low (D) and to determine the strength of recommendations as strong (1) or weak (2). The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. Recommendations were classified into three groups: (1) those directly targeting severe sepsis; (2) those targeting general care of the critically ill patient and considered high priority in severe sepsis; and (3) pediatric considerations. Results Key recommendations and suggestions, listed by category, include: early quantitative resuscitation of the septic patient during the first 6 h after recognition (1C); blood cultures before antibiotic therapy (1C); imaging studies performed promptly to confirm a potential source of infection (UG); administration of broad-spectrum antimicrobials therapy within 1 h of the recognition of septic shock (1B) and severe sepsis without septic shock (1C) as the goal of therapy; reassessment of antimicrobial therapy daily for de-escalation, when appropriate (1B); infection source control with attention to the balance of risks and benefits of the chosen method within 12 h of diagnosis (1C); initial fluid resuscitation with crystalloid (1B) and consideration of the addition of albumin in patients who continue to require substantial amounts of crystalloid to maintain adequate mean arterial pressure (2C) and the avoidance of hetastarch formulations (1B); initial fluid challenge in patients with sepsis-induced tissue hypoperfusion and suspicion of hypovolemia to achieve a minimum of 30 mL/kg of crystalloids (more rapid administration and greater amounts of fluid may be needed in some patients (1C); fluid challenge technique continued as long as hemodynamic improvement is based on either dynamic or static variables (UG); norepinephrine as the first-choice vasopressor to maintain mean arterial pressure ≥65 mmHg (1B); epinephrine when an additional agent is needed to maintain adequate blood pressure (2B); vasopressin (0.03 U/min) can be added to norepinephrine to either raise mean arterial pressure to target or to decrease norepinephrine dose but should not be used as the initial vasopressor (UG); dopamine is not recommended except in highly selected circumstances (2C); dobutamine infusion administered or added to vasopressor in the presence of (a) myocardial dysfunction as suggested by elevated cardiac filling pressures and low cardiac output, or (b) ongoing signs of hypoperfusion despite achieving adequate intravascular volume and adequate mean arterial pressure (1C); avoiding use of intravenous hydrocortisone in adult septic shock patients if adequate fluid resuscitation and vasopressor therapy are able to restore hemodynamic stability (2C); hemoglobin target of 7–9 g/dL in the absence of tissue hypoperfusion, ischemic coronary artery disease, or acute hemorrhage (1B); low tidal volume (1A) and limitation of inspiratory plateau pressure (1B) for acute respiratory distress syndrome (ARDS); application of at least a minimal amount of positive end-expiratory pressure (PEEP) in ARDS (1B); higher rather than lower level of PEEP for patients with sepsis-induced moderate or severe ARDS (2C); recruitment maneuvers in sepsis patients with severe refractory hypoxemia due to ARDS (2C); prone positioning in sepsis-induced ARDS patients with a Pao 2/Fio 2 ratio of ≤100 mm Hg in facilities that have experience with such practices (2C); head-of-bed elevation in mechanically ventilated patients unless contraindicated (1B); a conservative fluid strategy for patients with established ARDS who do not have evidence of tissue hypoperfusion (1C); protocols for weaning and sedation (1A); minimizing use of either intermittent bolus sedation or continuous infusion sedation targeting specific titration endpoints (1B); avoidance of neuromuscular blockers if possible in the septic patient without ARDS (1C); a short course of neuromuscular blocker (no longer than 48 h) for patients with early ARDS and a Pao 2/Fi o 2 180 mg/dL, targeting an upper blood glucose ≤180 mg/dL (1A); equivalency of continuous veno-venous hemofiltration or intermittent hemodialysis (2B); prophylaxis for deep vein thrombosis (1B); use of stress ulcer prophylaxis to prevent upper gastrointestinal bleeding in patients with bleeding risk factors (1B); oral or enteral (if necessary) feedings, as tolerated, rather than either complete fasting or provision of only intravenous glucose within the first 48 h after a diagnosis of severe sepsis/septic shock (2C); and addressing goals of care, including treatment plans and end-of-life planning (as appropriate) (1B), as early as feasible, but within 72 h of intensive care unit admission (2C). Recommendations specific to pediatric severe sepsis include: therapy with face mask oxygen, high flow nasal cannula oxygen, or nasopharyngeal continuous PEEP in the presence of respiratory distress and hypoxemia (2C), use of physical examination therapeutic endpoints such as capillary refill (2C); for septic shock associated with hypovolemia, the use of crystalloids or albumin to deliver a bolus of 20 mL/kg of crystalloids (or albumin equivalent) over 5–10 min (2C); more common use of inotropes and vasodilators for low cardiac output septic shock associated with elevated systemic vascular resistance (2C); and use of hydrocortisone only in children with suspected or proven “absolute”’ adrenal insufficiency (2C). Conclusions Strong agreement existed among a large cohort of international experts regarding many level 1 recommendations for the best care of patients with severe sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for this important group of critically ill patients. Electronic supplementary material The online version of this article (doi:10.1007/s00134-012-2769-8) contains supplementary material, which is available to authorized users.

Abstract The structure and stabilization of heated hydrogen jet flames in heated cross-flows was experimentally investigated in a configuration that is analogous to terrestrial gas turbine components. Three flames, with jet velocities ranging from 100 to 200 m/s, were investigated using particle image velocimetry and OH planar laser induced fluorescence in a total of 11 x–y and y–z planes. Additionally, laser Raman scattering was performed in the 200 m/s jet to characterize the thermo-chemical state. In all cases, the flame along the jet centerline plane consisted of two branches, one stabilized in the jet lee and one lifted above the jet trajectory. The positional stability of the lee-stabilized branch was greater in the higher jet velocity cases due to the larger and stronger recirculation zones created downstream of the injection point. The lifted flame branch was much more dynamic, with measured flame base axial positions ranging from the jet near field to the flame tip. This flame branch instantaneously resided downstream of regions with high extensive principal strain-rate, and the strain-rate significantly affected the thermo-chemical state. The Raman measurements indicated that the base of the lifted flame branch existed in locations where both tribrachial and/or stratified premixed flame behaviors are expected, depending on the instantaneous flame location. Accurately modeling these complex flame structures and flow-flame interactions therefore is necessary to properly simulate jet flames in cross-flows.

Quand le bilinguisme individuel résout les conflits linguistiques collectifs Frontière linguistique et discours identitaires à Fribourg/Freiburg : la perspective des jeunes adultes bilingues Cette thèse aborde la question linguistique fribourgeoise et l’importance de la langue à Fribourg / Freiburg (Suisse) dans la cohabitation de ses habitants. Elle porte également sur les points de discorde des groupes linguistiques, l’influence de la langue sur la construction des identités (collectives) et son rôle comme marqueur de différenciation entre les Fribourgeois alémaniques et romands. À cette fin, une analyse de discours portant sur un débat mené dans les quotidiens fribourgeois La Liberté et les Freiburger Nachrichten a été réalisée pour établir le contexte du travail. Ce débat, d’une durée de quatre ans, portait sur la nouvelle constitution cantonale. De plus, 17 entrevues furent menées auprès de 18 jeunes adultes bilingues (français et allemand) fribourgeois, afin d’aborder la question linguistique depuis une nouvelle perspective. L’analyse de discours a démontré l’existence de différentes perceptions de l’identité collective fribourgeoise, perceptions souvent liées à l’appartenance à un groupe linguistique : d’une part, la perception d’une ville francophone comptant une minorité germanophone prédomine chez les Fribourgeois romands, alors que, d’autre part, la perception d’une ville traditionnellement bilingue caractérise davantage les Fribourgeois alémaniques, divisant ainsi les Fribourgeois en deux camps. Les uns aspirent à une identité collective (bilingue) qui inclue l’altérité respective, tandis que les autres tentent de renforcer leur propre identité en soulignant l’altérité et en négligeant plutôt les points communs. Les entrevues réalisées ont démontré que la langue est le principal marqueur de différenciation des Fribourgeois alémaniques et romands – bien avant certains paramètres tels que les normes et valeurs, la mentalité, la religion, les habitudes de vie ou la culture. Les informateurs bilingues et la plupart du temps biculturels montrent des attitudes et perceptions particulières : se distinguant de plusieurs argumentaires présents dans l’analyse de discours, ceux-ci s’approprient les deux camps et montrent un sentiment d’appartenance avec le Fribourg romand et alémanique. Ce faisant, ils dénouent la majorité des sources de conflit et des contradictions de la question linguistique fribourgeoise. Leurs attitudes et perceptions spécifiques en font les médiateurs des groupes linguistiques dans le canton-pont et posent des questions potentiellement désagréables aux acteurs sociaux impliqués dans le débat linguistique fribourgeois. When individual bilingualism solves collective language conflicts Language frontier and identity discourse in Fribourg/Freiburg: the perspective of young bilingual adults This thesis deals with the Fribourg/Freiburg (Switzerland) language question and examines the significance of language for the cohabitation in Fribourg as well as it looks into fields of conflict for the language groups, the influence of language on the construction of a (collective) identity and the role of language as a criterion to make a distinction between German and French Swiss. Therefore, firstly, a discourse analysis was carried out to investigate a debate lasting four years that took place in the local newspapers La Liberté and Freiburger Nachrichten concerning a new cantonal constitution, to find out about the different positions in the Fribourg language question and to set the context and backdrop of this thesis. Secondly, 17 interviews with a total of 18 young bilingual (French/German) Fribourg adults have been executed, to take a new perspective on the Fribourg language question. The discourse analysis made varying perceptions of collective identity in the city apparent that are often language group related. The latter expressed itself in a primarily French Fribourg perception of a francophone city with a German speaking minority and a principally German Fribourg perception of a traditionally bilingual city thus creating two camps: one camp wishes for a (bilingual) collective identity, which includes the respective alterity, whereas the other camp tries to reinforce their identity by stressing the alterity and simultaneously rather excludes common grounds with the other camp. The interviews show that the language is the principal criterion to make a distinction between German and French Fribourg inhabitants – ranging before other criteria such as norms and values, mentalities, religion, ways of living or culture. The bilingual and mostly bicultural interviewees reveal a specific perception and attitude: in contrast to the results of the discourse analysis they integrate both camps in their personality, and also have a feeling of belonging with German and French Fribourg and are thus resolving most of the conflict points and contradictions in the Fribourg language question. This makes them mediators between the language groups in the bridge canton and poses potentially uncomfortable questions to the social actors involved in the Fribourg language debate. Wenn individuelle Zweisprachigkeit kollektive Sprachkonflikte löst Sprachgrenze und Identitätsdiskurse in Fribourg/Freiburg: Die Sicht junger bilingualer Erwachsener Die vorliegende Arbeit beschäftigt sich mit der Freiburger Sprachenfrage und untersucht die Bedeutung der Sprache in Fribourg/Freiburg (Schweiz) für das Zusammenleben der Einwohner sowie Konfliktfelder der Sprachgruppen, den Einfluss der Sprache auf die Konstruktion von (kollektiver) Identität und die Rolle der Sprache als Differenzierungsmerkmal zwischen Deutsch- und Welschfreiburgern. Dazu wurde einerseits eine Diskursanalyse einer vier Jahre wehrenden Debatte über eine neue Kantonsverfassung in den Freiburger Tageszeitungen La Liberté und den Freiburger Nachrichten unternommen, um Kontext und Hintergrund der Arbeit zu etablieren. Andererseits wurden 17 Interviews mit 18 jungen zweisprachigen (Französisch/Deutsch) Freiburger Erwachsenen geführt, um so eine neue Perspektive auf die Sprachenfrage zu bekommen. Die Diskursanalyse machte unterschiedliche, oft sprachgruppenabhängige Wahrnehmungen kollektiver Identität in der Stadt Freiburg deutlich: Die vornehmlich Welschfreiburger Wahrnehmung einer frankofonen Stadt mit deutschsprachiger Minderheit und die zuvorderst Deutschfreiburger Wahrnehmung einer traditionell zweisprachigen Stadt, so dass es zwei Lager gibt. Dabei wünscht sich ein Lager eine (zweisprachige) kollektive Identität, welche die jeweilige Alterität inkludiert; das andere Lager versucht seine Identität durch eine starke Betonung der Alterität zu bekräftigen, wobei es Gemeinsamkeiten mit dem anderen Lager eher exkludiert. Bei den Interviews zeigt sich, dass die Sprache das Hauptdifferenzierungsmerkmal zwischen Deutsch- und Welschfreiburgern ist – noch vor Parametern wie Normen und Werten, Mentalitäten, Religion, Lebensgewohnheiten oder Kultur. Die zweisprachigen und meist bikulturellen Informanten offenbaren eine spezielle Wahrnehmung und Haltung: In Abweichung zu vielen Argumentationen der Diskursanalyse vereinen sie beide Lager auf sich, haben ein Zugehörigkeitsgefühl zu Deutsch- und Welschfreiburg und lösen so die Konfliktpunkte und Widersprüche der Freiburger Sprachenfrage. Dies macht sie zu Mittlern zwischen den Sprachgruppen im Brückenkanton und stellt die sozialen Aktanten in der Freiburger Sprachendebatte vor potentiell unangenehme Fragen. [À l'origine dans / Was originally part of : Thèses et mémoires - FAS - Département de littératures et de langues modernes]

The traditional endmember extraction methods search for a fixed set of endmembers, each one assigned to a single material. However, in many real applications, the materials of interest may present spectral variability which is related to subtle absorption features crucial for their discrimination. Thus, extracting multiple spectra or bundles for different materials is considered a more effective approach for data analysis, accounting for intra-class spectral variability. In this work, a novel approach is introduced which aims at obtaining a full representation of materials in a given scene, specifically including those with low spectral contrast. The approach enables a traditional endmember extraction method, the N-FINDR, to extract image endmember bundles exploiting the original spectral bands through a spectral space splitting. Experiments were conducted using an airborne hyperspectral dataset for extracting endmembers of mafic and ultramafic lithological units and preliminary results show the potential usefulness of the new approach.

ZusammenfassungIm digitalen Informationszeitalter stellen Hochschulrechenzentren (HRZ) einen zentralen Bestandteil zur Erfüllung operativer Aufgaben in Forschung, Lehre und Verwaltung von Hochschulen dar. Dabei stehen HRZ vor unterschiedlichen Herausforderungen, die durch diverse Nutzeranforderungen sowie Anforderungen bezüglich IT-Sicherheit und Regulatorik hervorgerufen werden. Um diese Herausforderungen zu bewältigen, ist es essenziell, bisher dezentral und heterogen geprägte IT-Services stetig zu professionalisieren. Dadurch entsteht die Notwendigkeit, sich für einen nachhaltigen Betrieb der HRZ stärker an etablierten Servicestandards und Anforderungen von hochschulinternen sowie hochschulexternen Nutzergruppen zu orientieren. Ein professionelles IT-Servicemanagement (ITSM) wird damit zur Grundlage für HRZ. Im Rahmen eines durch das bayerische Wissenschaftsministerium geförderten Projektes wird durch eine vergleichende Fallstudie zum einen der Status des ITSM der bayerischen HRZ systematisch erfasst, zum anderen darauf aufbauend eine Weiterentwicklung unterstützt. Dazu wurden Interviews und Selbstevaluierungen von neun unterschiedlichen Hochschulen durchgeführt und die Ergebnisse anschließend evaluiert. In diesem Beitrag werden die zentralen Erkenntnisse vorgestellt und Handlungsempfehlungen daraus abgeleitet.

Abstract The dynamics of major flow structures were studied in a gas turbine model combustor for perfectly premixed swirl-stabilized flames under a variety of reacting and non-reacting conditions using high-repetition-rate laser diagnostics. The studied combustor is a target case for the International Workshop on Advanced Measurement Techniques and Computational Methods for Premixed and Partially Premixed Combustion. Measurements were taken of the three-component velocity field, OH planar laser induced fluorescence, and OH∗ chemiluminescence at a rate of 10 kHz for nine different flow conditions, covering a range of thermal powers (Pth = 10–35 kW) and equivalence ratios (ϕ = 0.65–0.8). Under all non-reacting conditions, the dominant flow structure was a helical vortex core (HVC) that rotated around the burner at a frequency represented by a constant Strouhal number StH,NR = 0.78. However, igniting the burner significantly altered the flow structures. At most conditions, the strength and frequency of the HVC increased relative to the corresponding non-reacting case. The HVC frequency in such cases was once again represented by a constant Strouhal number of StH,R = 0.88, irrespective of the thermal power or equivalence ratio. The HVC frequency was considerably higher than the frequency of the self-excited thermo-acoustic oscillations exhibited by the burner. However, at other conditions, combustion prevented formation of the HVC. In such cases, the dominant flow structure dynamics were periodic shear layer oscillations and shedding of toroidal vortices at the thermo-acoustic frequency. Cases in which combustion prevented formation of the HVC included those at low thermal powers (Pth ⩽ 15 kW) and the highest equivalence ratio (ϕ = 0.8). A distinct relationship was found between the flow structure geometry and the pressure oscillation amplitude, with cases having an HVC resulting in higher pressure oscillations.

Wie konnen wir die verschiedenen und zum Teil sehr bizarren Symptome bei psychiatrischen Erkrankungen klassifizieren, verstehen und begreifen? Dies ist Aufgabe der sog. „Psychopathologie“. Das vorliegende Kapitel diskutiert, wie die psychopathologischen Symptome auf der Grundlage der Verknupfung zwischen neuronalen und psychodynamischen Mechanismen verstanden und klassifiziert werden konnen.