Pancreatic Resections for Advanced M1-Pancreatic Carcinoma: The Value of Synchronous Metastasectomy

Background. For M1 pancreatic adenocarcinomas pancreatic resection is usually not indicated. However, in highly selected patients synchronous metastasectomy may be appropriate together with pancreatic resection when operative morbidity is low. Materials and Methods. From January 1, 2004 to December, 2007 a total of 20 patients with pancreatic malignancies were retrospectively evaluated who underwent pancreatic surgery with synchronous resection of hepatic, adjacent organ, or peritoneal metastases for proven UICC stage IV periampullary cancer of the pancreas. Perioperative as well as clinicopathological parameters were evaluated. Results. There were 20 patients (9 men, 11 women; mean age 58 years) identified. The primary tumor was located in the pancreatic head (n = 9, 45%), in pancreatic tail (n = 9, 45%), and in the papilla Vateri (n = 2, 10%). Metastases were located in the liver (n = 14, 70%), peritoneum (n = 5, 25%), and omentum majus (n = 2, 10%). Lymphnode metastases were present in 16 patients (80%). All patients received resection of their tumors together with metastasectomy. Pylorus preserving duodenopancreatectomy was performed in 8 patients, distal pancreatectomy in 8, duodenopancreatectomy in 2, and total pancreatectomy in 2. Morbidity was 45% and there was no perioperative mortality. Median postoperative survival was 10.7 months (2.6–37.7 months) which was not significantly different from a matched-pair group of patients who underwent pancreatic resection for UICC adenocarcinoma of the pancreas (median survival 15.6 months; P = .1). Conclusion. Pancreatic resection for M1 periampullary cancer of the pancreas can be performed safely in well-selected patients. However, indication for surgery has to be made on an individual basis

"Quasi eingebettet in die Schrift" Der doppelte Erzählboden popmoderner Oberflächenbeschreibung und der ästhetische Fundamentalismus in Christian Krachts Roman 1979

[À l'origine dans / Was originally part of : Thèses et mémoires - FAS - Département de littératures et de langues modernes]Cette mémoire est une analyse du subtexte immanent dans le roman « 1979 » (2001) de Christian Kracht, auteur suisse, qui est le plus connu pour son début « Faserland » (1995). Ces oeuvres sont situées dans le mouvement de la littérature Pop allemande des années 1990 et en résultent en même temps. Dans ce contexte, le climat socio-politique après la réunification, notamment le Literaturstreit, jouera un rôle important dans mon interprétation comme fond de la poésie de Kracht. J’exposerai les difficultés que le discours de la littérature Pop porte en ce qui concerne l’œuvre de cet auteur, qui, même s’il est vu en général comme fondateur de ce genre littéraire en Allemagne, ne considère pas ses textes comme littérature Pop dans ses déclarations notoirement problématiques. Je devrais objecter que Kracht est en combat avec la littérature Pop d’une façon stylistique et pas rarement ironique, ce qui traverse la définition étroite dominante. Il fait cela en adoptant sur l’un côté le trait le plus signifiant du genre, à savoir le caractère superficiel extrêmement descriptif et en transmettant sur l’autre côté un message moral profond, ce qui rend impossible la classification de ses textes comme Pop, signifiant seulement le divertissement ou l’archivisme de Moritz Bassler. En fait, la fréquence de signifiants de Pop dans les textes de Kracht créent par leur arrangement un réseau de sens qui, dans le paradigme post- moderne, peut être décrit le mieux avec le terme « rhizome » de Gilles Deleuze et Félix Guattari. En faisant ça, Kracht suit une autre tradition qui traverse les limites de la littérature Pop, comme il se sert de la décadence, de l’esthétisme et du symbolisme du fin-du-siècle d’un Hugo von Hofmannsthal, d’un Stefan George et d’un Joris-Karl Huysmans avec leurs pointes de mise en garde contre les déficits du modernisme, du libéralisme et du capitalisme, d’une façon nommée « fondamentalisme esthétique » par le sociologiste Stefan Breuer. Cette recherche se référera aux interprétations originales des textes source, aux évaluations de littérature d’accompagnement, à savoir des manuels scolaires en critique littéraire, en sociologie et en histoire allemande, aux comptes rendu, dissertations et entrevues et aux textes philosophiques. Cette mémoire est écrit en allemand.This master's thesis is an analysis of the subtext immanent in the novel "1979" (2001) by Swiss author, Christian Kracht, who is best known for his debut, "Faserland" (1995). These works are situated in and result from the 1990's movement of German pop literature. In that context, the socio-political climate after the re-unification, most notably the Literaturstreit, plays an important role in my interpretation as the background to Kracht's poetics. I delineate the difficulties that the pop literature discourse carries both, as a literary category and in regard to this author's work, taking into consideration his notoriously problematic statements to the effect that he does not consider his texts to be pop literature, in spite of being commonly regarded as the founder of this literary form in Germany. I shall argue that Kracht engages in a stylistic and more often than not ironic play with pop literature, which transgresses the dominant narrow definition of it. He does so by adopting on the one hand its most-defining feature of extreme descriptive superficiality, yet by conveying on the other hand a moral message of profound dimensions, which renders impossible the classification of his texts as pop, neither in the sense of mere entertainment nor in the sense of Moritz Bassler’s archivism. In fact, the very arsenal of pop signifiers present in Kracht's texts create through their arrangement a web of meaning, which in the post-modern paradigm can be best described with Gilles Deleuze's and Félix Guattari's term “rhizome." By doing so Kracht follows in the footsteps of another tradition which transgresses the boundaries of pop literature, as he reaches back to the aestheticistic décadence and symbolism at the fin-de-siècle of a Hugo von Hofmannsthal, a Stefan George, and a Joris-Karl Huysmans, with their strong undertones of warnings against the shortfalls of modernism, liberalism, and capitalism, in a fashion that is termed “aesthetic fundamentalism” by Stefan Breuer. This research draws on original interpretations of the source texts, on evaluations of secondary literature such as scholarly works in German literary criticism, sociology and history, on book reviews, essays and interviews, and on philosophical texts. The thesis is written in German.Gegenstand der vorliegenden Arbeit ist der narrative Subtext im Roman 1979 (2001) des Schweizer Autoren Christian Kracht, der vor allem mit seinem Romandebüt Faserland (1995) bekannt wurde. Seine Texte stehen im Zusammenhang mit der Neuen Deutschen Popliteratur der 90er Jahre. In diesem Kontext hat auch das soziokulturelle Klima nach der Wiedervereinigung eine wichtige Rolle, das sich am prägnantesten im Literaturstreit äußerte, weshalb dieser in der hier vorgenommenen Intepretation von Krachts Poetik seinen Platz findet. Außerdem soll aufgezeigt werden, inwieweit die Neue Deutsche Popliteratur sowohl als gattungstechnische Kategorie als auch im Bezug auf Krachts Werk problematisch ist. Dies entspricht den Beteuerungen des Autors, dass er keine Popliteratur schreibe, obwohl er als ihr Gründer gilt. Das Argument dieser Arbeit ist, dass Kracht auf stilistische und oft ironische Weise mit Popliteratur spielt, wodurch er die bestehende enge Definition dieser transgressiert. Da er einerseits das bezeichnenste Merkmal von Popliteratur, nämlich die Oberflächenbeschreibung, übernimmt, andererseits aber dadurch eine tiefe moralische Aussage macht, lassen sich seine Texte nicht als Pop verorten,weder als Unterhaltung, noch im Sinne von Moritz Baßlers Archivismus. Vielmehr ergeben die von Kracht versammelten Pop-Signifikanten in ihrer Vernetzung ein Sinngebäude, das in postmoderner Parlanz mit Gilles Deleuze und Félix Guattari als „Rhizom“ bezeichnet werden kann. Indem Kracht so verfährt, knüpft er ebenfalls an eine Tradition jenseits von Popliteratur an, und zwar an die ästhetizistische décadence und den Symbolismus des fin de siècle eines Hugo von Hofmannsthal, Stefan George und Joris-Karl Huysmans, sowie deren Warnungen vor den Mängeln des Modernismus, Liberalismus und Kapitalismus, wobei diese Einstellung von Stefan Breuer als ästhetischer Fundamentalismus bezeichnet wird

Electron-phonon scattering in quantum point contacts

We study the negative correction to the quantized value $2e^2/h$ of the conductance of a quantum point contact due to the backscattering of electrons by acoustic phonons. The correction shows activated temperature dependence and also gives rise to a zero-bias anomaly in conductance. Our results are in qualitative agreement with recent experiments studying the 0.7 feature in the conductance of quantum point contacts.Comment: 4 pages, no figure

Stub model for dephasing in a quantum dot

As an alternative to Buttiker's dephasing lead model, we examine a dephasing stub. Both models are phenomenological ways to introduce decoherence in chaotic scattering by a quantum dot. The difference is that the dephasing lead opens up the quantum dot by connecting it to an electron reservoir, while the dephasing stub is closed at one end. Voltage fluctuations in the stub take over the dephasing role from the reservoir. Because the quantum dot with dephasing lead is an open system, only expectation values of the current can be forced to vanish at low frequencies, while the outcome of an individual measurement is not so constrained. The quantum dot with dephasing stub, in contrast, remains a closed system with a vanishing low-frequency current at each and every measurement. This difference is a crucial one in the context of quantum algorithms, which are based on the outcome of individual measurements rather than on expectation values. We demonstrate that the dephasing stub model has a parameter range in which the voltage fluctuations are sufficiently strong to suppress quantum interference effects, while still being sufficiently weak that classical current fluctuations can be neglected relative to the nonequilibrium shot noise.Comment: 8 pages with 1 figure; contribution for the special issue of J.Phys.A on "Trends in Quantum Chaotic Scattering

Probe-Configuration-Dependent Decoherence in an Aharonov-Bohm Ring

We have measured transport through mesoscopic Aharonov-Bohm (AB) rings with two different four-terminal configurations. While the amplitude and the phase of the AB oscillations are well explained within the framework of the Landaur-B\"uttiker formalism, it is found that the probe configuration strongly affects the coherence time of the electrons, i.e., the decoherence is much reduced in the configuration of so-called nonlocal resistance. This result should provide an important clue in clarifying the mechanism of quantum decoherence in solids.Comment: 4 pages, 4 figures, RevTe

Indications and Early Outcomes for Total Pancreatectomy at a High-Volume Pancreas Center

Background. This study aimed to analyse the most common current indications for total pancreatectomy (TP) at a high-volume pancreas center. Method. Prospectively collected data on indications and short-term outcome of all TP's performed from January 2004 until June 2008 were analysed. Results. The total pancreatectomies (TP) were 63, i.e., 6.7% of all pancreatic procedures (n = 948). Indications for TP were classified into 4 groups: tumors of advanced stage, n = 23 (36.5%), technical problems due to soft pancreatic tissue, n = 18 (28.6%), troubles due to perioperative surgical complications, n = 15 (23.8%), and therapy-resistant pain due to chronic pancreatitis, n = 7 (11.1%). Surgical complications occurred in 23 patients (36.5%). The mortality in elective TP was 6.25%. Median postoperative stay was 21 days. Mortality, morbidity and the other perioperative parameters differed substantially according to the indication for pancreatectomy. Conclusion. Total pancreatectomy is definitely indicated for a limited range of elective and emergency situations. Indications can be: size or localisation of pancreatic tumor, trouble, technical diffuculties and therapy-refractory pain in chronic pancreatitis. A TP due to perioperative complications (troubles) after pancreatic resections is doomed by extremely high morbidity and mortality and should be avoided

Angular velocity integration in a fly heading circuit

Many animals maintain an internal representation of their heading as they move through their surroundings. Such a compass representation was recently discovered in a neural population in the Drosophila melanogaster central complex, a brain region implicated in spatial navigation. Here, we use two-photon calcium imaging and electrophysiology in head-fixed walking flies to identify a different neural population that conjunctively encodes heading and angular velocity, and is excited selectively by turns in either the clockwise or counterclockwise direction. We show how these mirror-symmetric turn responses combine with the neurons' connectivity to the compass neurons to create an elegant mechanism for updating the fly's heading representation when the animal turns in darkness. This mechanism, which employs recurrent loops with an angular shift, bears a resemblance to those proposed in theoretical models for rodent head direction cells. Our results provide a striking example of structure matching function for a broadly relevant computation

Temperature and magnetic-field dependence of the quantum corrections to the conductance of a network of quantum dots

We calculate the magnetic-field and temperature dependence of all quantum corrections to the ensemble-averaged conductance of a network of quantum dots. We consider the limit that the dimensionless conductance of the network is large, so that the quantum corrections are small in comparison to the leading, classical contribution to the conductance. For a quantum dot network the conductance and its quantum corrections can be expressed solely in terms of the conductances and form factors of the contacts and the capacitances of the quantum dots. In particular, we calculate the temperature dependence of the weak localization correction and show that it is described by an effective dephasing rate proportional to temperature.Comment: 24 pages, 14 figure

Synthesis and Interactions of 7-Deoxy-, 10-Deacetoxy, and 10-Deacetoxy-7-Deoxypaclitaxel with NCI/ADR-RES Cancer Cells and Bovine Brain Microvessel Endothelial Cells

Please note that this is an author-produced PDF of an article accepted for publication following peer review. The publisher version is available on its site.7-Deoxypaclitaxel, 10-deacetoxypaclitaxel and 10-deacetoxy-7-deoxypaclitaxel were prepared and evaluated for their ability to promote assembly of tubulin into microtubules, their cytotoxicity against NCI/ADR-RES cells and for their interactions with Pglycoprotein in bovine brain microvessel endothelial cells. The three compounds were essentially equivalent to paclitaxel in cytotoxicity against NCI/ADR-RES cells. They also appeared to interact with P-glycoprotein in the endothelial cells with the two 10-deacetoxy compounds having less interaction than paclitaxel and 7-deoxypaclitaxel. ©2000 Elsevier Science Ltd. All rights reserved