3,009 research outputs found
A Bijection between classes of Fully Packed Loops and Plane Partitions
It has recently been observed empirically that the number of FPL
configurations with 3 sets of a, b and c nested arches equals the number of
plane partitions in a box of size a x b x c. In this note, this result is
proved by constructing explicitly the bijection between these FPL and plane
partitions
Trimming of a Broken Migrated Biliary Metal Stent with the Nd:YAG Laser
Biliary metal stents are a permanent solution for bile duct stenosis. Complications can arise when the stent migrates, breaks or is overgrown by tumour. The following case demonstrates how a Nd:YAG laser can be used to solve these problems. A 93-year-old man presented with jaundice and fever. Two years earlier a 6-cm metal stent had been implanted into a postinflammatory stenosis of the common bile duct after recurrent cholangitis and repetitive plastic stenting. Duodenoscopy showed that the stent was broken. It had migrated about 3 cm into the duodenum, leading to kinking of the stent and breaking of the wires. The stent was also occluded. It was necessary to purge the common bile duct and to introduce a second stent. However, the only way to reach the papilla was through the broken wires. Placing a second stent this way was impossible. Thus we trimmed the stent with a Nd:YAG laser. The piece that had migrated into the duodenum was retrieved. Now the papilla could be reached. The rest of the metal stent was purged with NaCl 0.9%. A second metal stent was placed. Since an Nd:YAG laser is part of the equipment of most endoscopy units, it can be used to trim a broken or migrated biliary metal stent
A new approach to the inverse problem for current mapping in thin-film superconductors
A novel mathematical approach has been developed to complete the inversion of
the Biot-Savart law in one- and two-dimensional cases from measurements of the
perpendicular component of the magnetic field using the well-developed
Magneto-Optical Imaging technique. Our approach, especially in the 2D case, is
provided in great detail to allow a straightforward implementation as opposed
to those found in the literature. Our new approach also refines our previous
results for the 1D case [Johansen et al., Phys. Rev. B 54, 16264 (1996)], and
streamlines the method developed by Jooss et al. [Physica C 299, 215 (1998)]
deemed as the most accurate if compared to that of Roth et al. [J. Appl. Phys.
65, 361 (1989)]. We also verify and streamline the iterative technique, which
was developed following Laviano et al. [Supercond. Sci. Technol. 16, 71 (2002)]
to account for in-plane magnetic fields caused by the bending of the applied
magnetic field due to the demagnetising effect. After testing on
magneto-optical images of a high quality YBa2Cu3O7 superconducting thin film,
we show that the procedure employed is effective
Prolonged myocardial stunning after thrombolysis: can left ventricular function be assessed definitely at hospital discharge?
To assess whether myocardial dysfunction after acute reperfusion (âstunning') may show delayed recovery, 33 patients of the European Cooperative Study (rtPA vs placebo) had radionuclide angiocardiography on day 9 and after 3-6 months. Sixteen patients (13 inferior, three anterior infarcts) had a normal left ventricular ejection fraction (LVEF) which remained unchanged (55.4 vs 53.9%). In contrast, LVEF of 17 patients (10 inferior, seven anterior infarcts) with depressed values on day 9 improved during follow-up from 38.8 to 45.2% (P<0.01). Improvement was only observed in patients with early reperfusion defined a priori as peak creatine kinase valuĂš †15 h of pain onset (from 40.9 to 49.3%; P<0.05) in contrast to patients without reperfusion (from 34.0 to 35.2%; ns). Accordingly, LVEF increased in patients with open infarct-related arteries at hospital discharge (n = 8; P = 0.053) but not with persistent occlusion (n = 7; P = 0.11). Thus, a depressed LVEF observed 9 days after reperfusion may show delayed recovery due to prolonged stunning. Therefore, after thrombolysis, left ventricular function may not be evaluated definitively at hospital discharge; results of such studies should be interpreted with cautio
Ideal and reality: do countries adopt and follow recommended procedures in comprehensive multiyear planning guidelines for national immunization programmes?
BACKGROUND: Meticulous steps and procedures are proposed in planning guidelines for the development of comprehensive multiyear plans for national immunization programmes. However, we know very little about whether the real-life experience of those who adopt these guidelines involves following these procedures as expected. Are these steps and procedures followed in practice? We examined the adoption and usage of the guidelines in planning national immunization programmes and assessed whether the recommendations in these guidelines are applied as consistently as intended.
METHODS: We gathered information from the national comprehensive multiyear plans developed by 77 low-income countries. For each of the 11 components, we examined how each country applied the four recommended steps of situation analysis, problem prioritization, selection of interventions, and selection of indicators. We then conducted an analysis to determine the patterns of alignment of the comprehensive multiyear plans with those four recommended planning steps.
RESULTS: Within the first 3Â years following publication of the guidelines, 66 (86%) countries used the tool to develop their comprehensive multiyear plans. The funding conditions attached to the use of these guidelines appeared to influence their rapid adoption and usage. Overall, only 33 (43%) countries fully applied all four recommended planning steps of the guidelines.
CONCLUSIONS: Adoption and usage of the guidelines for the development of comprehensive multiyear plans for national immunization programmes were rapid. However, our findings show substantial variation between the proposed planning ideals set out in the guidelines and actual use in practice. A better understanding of factors that influence how recommendations in public health guidelines are applied in practice could contribute to improvements in guidelines design. It could also help adjust strategies used to introduce them into public health programmes, with the ultimate goal of a greater health impact
Stellenwert der endoskopischen Axilladissektion beim invasiven Mammakarzinom
Zusammenfassung: Grundlagen: Die Axilladissektion liefert zuverlĂ€ssige prognostische Information, bestimmt mehrheitlich die adjuvante Therapie und reduziert die axillĂ€ren Tumorrezidive. Die MorbiditĂ€t nach Axilladissektion kann jedoch nicht vernachlĂ€ssigt werden (sensible Störungen, Schmerzen, motorische SchwĂ€che, Lymphödem). Patientinnen mit kleinen Tumoren (pT1a, b, c) könnten von neueren weniger invasiven Verfahren (endoskopische Axilladissektion) oder von selektiveren Methoden (Sentinel-lymph-node-Procedere) profitieren. In dieser prospektiven Studie wurde die axilloskopische Lymphadenektomie evaluiert. Methodik: 55 klinisch nodal negative Patientinnen (Durchschnittsalter: 60 Jahre [30 bis 86 Jahre]) wurden von einem Chirurgen endoskopisch operiert (Januar 1996 bis Juni 1998). Nach Liposuktion des axillĂ€ren Fettkörpers wurden die Lymphknoten von Level I+II identifiziert und unter direkter endoskopischer Sicht reseziert (erfolgreiches Verfahren in 95 %: n=52). Die Patientinnen wurden entsprechend dem Nachsorgeschema alle 4 Monate kontrolliert. Nach einer mittleren Beobachtungszeit von 22 Monaten (7 bis 37 Monate; n=51 [eine Patientin verweigerte die Nachsorge]) wurden die Patientinnen mit einem Evaluationsfragebogen, einem Interview und einer klinischen Untersuchung (inklusiv Schultergelenksfunktion, Zirkumferenzmessungen der oberen ExtremitĂ€t) nachkontrolliert. Ergebnisse: Durchschnittlich wurden 13,3 (5 bis 25) Lymphknoten endoskopisch entfernt. Nodal positive Lymphknoten wurden in 31 % (n=16) beobachtet. Der Durchschnittswert der positiven Lymphknoten/Patientin betrug 3,1 (1 bis 10). Acht Serome (15 %) muĂten in der frĂŒhpostoperativen Phase punktiert werden. Es traten keine HĂ€matome, jedoch ein Infekt in der Axilla nach Chemotherapie auf (2 %). Nach einer mittleren Beobachtungszeit von 22 Monaten (7 bis 37 Monate) konnten keine axillĂ€ren Rezidive nachgewiesen werden. Eine subkutane Implantationsmetastase in der Narbe eines Trokarkanals (1/55, 2 %) wurde diagnostiziert und reseziert. Klinisch traten keine Lymphödeme auf. Die frĂŒhe Mobilisation des Schultergelenkes war subjektiv und objektiv gut. SchluĂfolgerungen: Die durchschnittlich 13 axilloskopisch entfernten Lymphknoten entsprechen der Anzahl resezierter Lymphknoten bei offener Axilladissektion. Die MorbiditĂ€t dieses in Evaluation begriffenen Verfahrens ist niedrig. Nach einer mittleren Beobachtungszeit von 22 Monaten wurde ein Implantationsrezidiv im subkutanen Kanal des anterioren Arbeitstrokar nachgewiesen. Eine lĂ€ngere Beobachtungszeit ist nötig, um die Technik empfehlen zu können. Es zeichnet sich ab, daĂ die endoskopische, axillĂ€re Lymphknotendissektion durch das selektivere Sentinel-lymph-node-Verfahren abgelöst wir
A 40th deg and order gravitational field model for Mars
Understanding the origin and evolution of major photographic features on Mars, such as the hemispheric dichotomy and Tharsis rise, will require improved resolution of that planet's gravitational and topographic fields. The highest resolution gravity model for Mars published to date was derived from Doppler tracking data from the Mariner 9 and Viking 1 and 2 spacecraft, and is of 18th degree and order. That field has a maximum spatial resolution of approx. 600 km, which is comparable to that of the best topographic model. The resolution of previous gravity models was limited not by data density, but rather by the computational resources available at the time. Because this restriction is no longer a limitation, the Viking and Mariner data sets were reanalyzed and a gravitational field was derived complete to the 40th degree and order with a corresponding maximum spatial resolution of 300 km where the data permit
Lorentz and CPT Invariance Violation In High-Energy Neutrinos
High-energy neutrino astronomy will be capable of observing particles at both
extremely high energies and over extremely long baselines. These features make
such experiments highly sensitive to the effects of CPT and Lorentz violation.
In this article, we review the theoretical foundation and motivation for CPT
and Lorentz violating effects, and then go on to discuss the related
phenomenology within the neutrino sector. We describe several signatures which
might be used to identify the presence of CPT or Lorentz violation in next
generation neutrino telescopes and cosmic ray experiments. In many cases,
high-energy neutrino experiments can test for CPT and Lorentz violation effects
with much greater precision than other techniques.Comment: 27 pages, 8 figure
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