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Notes: Summary It is well-known that periodic solutions of semilinear wave equations can be obtained as critical points of related functionals. In the situation that we studied, there is usually an obvious solution obtained as a solution of linear problem. We formulate a dual variational problem in such a way that the obvious solution is a local minimum. We then find additional non-obvious solutions via a numerical mountain pass algorithm, based on the theorems of Ambrosetti, Rabinowitz and Ekeland. Numerical results are presented.

Notes: Possible mechanism(s) of resistance to auxinic herbicides in wild mustard (Sinapis arvensis L.) were investigated by characterizing responses of susceptible and resistant biotypes to 2,4-D, di-camba or picloram. No differences between bio-types were observed in absorption, translocation, or metabolism of foliar-applied radiolabelled herbicides. In contrast, the levels of ethylene production varied between biotypes. The susceptible biotype produced twofold and sixfold more ethylene than the resistant biotype within 4 h and 44 h of herbicide application, respectively. These results suggest that the mechanism of resistance in wild mustard is not due to differences in absorption, translocation, or metabolism. Ethylene production studies imply that resistance to auxinic herbicides may be attributed to altered target site(s) of action. Bases physiologiques de la résistance aux herbicides auxiniques d'un biotype de moutarde des champs (Sinapis arvensis L.)Les mécanismes possibles de la résistance aux herbicides auxiniques chez la moutarde des champs (Sinapis arvensis L.) ont été recherchés en caractérisant les réponses de biotypes résis-tants et sensibles au 2,4-D, au dicamba et au pi-clorame. Aprés application des herbicides radioactifs sur le feuillage, aucune différence d'absorption, de migration ou de métabolisme n'a été observée. Par contre, la production d'éthylene différait entre les biotypes. Le biotype sensible produisait 2 et 6 fois plus d'éthylène que le biotype sensible, respectivement 4 et 44 heures après l'application d'herbicide. Ces résultats sug-gèrent que la résistance aux herbicides auxiniques chez la moutarde des champs n'est pas due à des différences d'absorption, de migration ou de métabolisme mais pourrait provenir d'une altération du site d'action.Physiologische Untersuchung der Resistenz eines Acker-Senf-(Sinapis arvensis-) Biotyps gegenüber WuchsstoffherbizidenDer mögliche Mechanismus der Resistenz gegenüber Wuchsstoffherbiziden beim Acker-Senf (Sinapis arvensis L.) wurde unhand der Reaktion von empfindlichen und resistenten Biotypen gegenüber 2,4-D, Dicamba oder Picloram untersucht. Hinsichtlich Absorption, Translokation oder Metabolismus der auf die Blätter applizierten, radioaktiv markierten Her-bizide wurden keine Unterschiede beobachtet. Die Ethylenbildung variierte jedoch zwischen den Biotypen. Der empfindliche produzierte in-nerhalb 4 oder 44 Stunden nach der Herbizid-applikation 2-bzw. 6mal mehr Ethylen als der resistente. Aus den Ergebnissen läßt sich schließen, daß beim Acker-Senf der Resisten-zmechanismus nicht in der Absorption, der Translokation oder dem Metabolismus liegt, sondern die Ethylenbildung daran beteiligt ist, wo die Wirkorte fur die Wuchsstoffherbizide liegen.

Notes: Helicobacter pylori has attracted increasing attention among gastroenterologists because of its pathogenic potential, stimulating the search for non-invasive diagnostic tests.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:In this study the efficacy of a new enzyme immunoassay designed to detect H. pylori antigens in stools (HpSA) was evaluated before and after eradication therapy.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:HpSA was performed on stool samples collected from 268 patients whose H. pylori status was defined on the basis of concordant results for the 13C-urea breath test, rapid urease test and histology. The H. pylori-positive patients were treated with a 1-week triple therapy to eradicate the infection. One (T30) and 3 months (T90) after the end of therapy, 13C-urea breath test and HpSA were repeated in the treated patients.〈section xml:id="abs1-4"〉〈title type="main"〉Results:The overall diagnostic accuracy of HpSA at T30 (83%, 95% confidence interval (CI) 77–89%) was significantly lower in comparison to the values obtained at baseline (94%, 95% CI: 91–97%) and at T90 (97%, 95% CI: 94–99%). No significant difference was found between the diagnostic accuracy of HpSA at baseline and at T90 (P=0.253).〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:The present data suggest that HpSA provides a low diagnostic accuracy when used shortly after treatment. It needs a longer period of follow-up (8–12 weeks) to reach a reliability comparable to the 13C-urea breath test.

Notes: Infection by any of the four serotypes of dengue viruses (DEN-1, -2, -3 and -4) may result in either a relatively benign fever, called dengue fever (DF), a fatal disease, such as dengue haemorrhagic fever (DHF) or dengue shock syndrome (DSS). Several lines of evidence suggest that soluble immune response mediators may be involved in the severity of dengue infections. For instance, elevated seric levels of IL-8 are a common feature in DHF patients. Because other chemokines, cytokines, adhesion molecules, chemokine and cytokine receptors, as well as cytokine-related molecules may also be involved in dengue virus pathogenesis, we aimed at analysing the gene expression of such molecules in the course of an in vitro DEN-2 infection of human peripheral blood monocyte-derived macrophages, a cell type regarded as a primary target for DEN. Nylon membrane gene arrays containing 375 different human cytokine-related genes were used as a first step to search for differentially expressed genes upon infection. Transcripts for IL-8, IL-1β, osteopontin, GRO-α, -β and -γ, I-309, and some other molecules showed to be upregulated upon infection, whereas others such as MIC-1, CD27L and CD30L, were downregulated. Four genes were selected for reverse transcriptase-polymerase chain reaction based gene-expression analysis as a way to partially confirm microarray results. This approach pointed out 25 macrophage-expressed cytokine-related genes that could be relevant in DEN-2 pathogenesis.

Notes: Summary It is still controversial whether the familial environment plays a role in the diffusion of HCV infection. The aim of this study was to evaluate the prevalence of anti-HCV positivity in the household contacts of patients with HCV-related chronic hepatitis. Nearly all the household contacts of 113 subjects with anti-HCV+ chronic hepatitis (100/113 spouses and 260/290 children) were investigated. Anti-HCV was determined by means of ELISA II and was confirmed by RIBA II. Anti-HCV positivity was found in 27% of the spouses and in 1.9% of the children. Prevalence of anti-HCV positivity in spouses correlated positively with the duration of the marital status. Seventeen/32 (53.1%) of anti-HCV-positive subjects were found to have chronic hepatitis. This study indicates that intrafamilial diffusion of HCV infection is mostly accounted for by horizontal, in particular spouse to spouse, transmission and that spouse to spouse transmission of HCV infection correlates positively with the duration of marital status.

Notes: Abstract: The energy loss of deuterons in 3He gas was measured at Ed = 15 to 100 keV using the 3He pressure dependence of the 3He(d,p) 4He cross-section at a given incident energy. At the highest energies, the observed energy loss is in good agreement with a standard compilation. However, with decreasing energy the experimental values drop steadily below the theoretical values and near Ed = 18 keV they drop sharply (within 1 keV) reaching the domain of nuclear stopping power. This threshold behavior is due to the minimum 1s→ 2s electron excitation of the He target atoms, i.e. it is a quantum effect. Some consequences are discussed.

Notes: Abstract Vascular complications remain a significant nonimmunologic source of pancreas allograft loss. From February 1993 through January 1998, we performed 98 simultaneous pancreas-kidney transplantations (SPK) using pancreatic exocrine bladder drainage in patients with type 1 insulin-dependent diabetes mellitus and end-stage renal disease. They originally received quadruple immunosuppression, and since May 1997 triple immunosuppression protocol (tacrolimus, mycophenolate mofetil, and steroids). The patients' mean age was 37 years (range 24–53 years), including 50 women and 48 men with a mean follow-up of 42 months. The overall rate of vascular complications was 6 % (5 patients). The vascular complications were as follows: late thrombosis of the Y with persistent pancreas allograft function (n = 1), rupture of a pseudoaneurysm of the superior mesenteric artery (PSMA) with an arteriovenous fistula (AVF) (n = 1), thrombosis of the splenic vein (SV) (n = 3), complete thrombosis of the superior mesenteric vein (SMV) and splenic vein (n = 1). The patient with PSMA underwent surgical correction of the AVF and PSMA with preservation of the allograft pancreas function. The other patient with late thrombosis of the Y-graft required no treatment. All 3 patients with SV thrombosis were systemically heparinized followed by oral anticoagulation. The patient with complete thrombosis required surgical thrombectomy of the SMV and SV followed by heparinization and oral anticoagulation. All 6 patients including the 4 with thrombosis had preservation of the pancreas function. Serial pancreas ultrasound showed resolution and improvement with recanalization of the splenic vein and superior mesenteric vein in those patients with thrombosis. We describe our vascular experience with salvage of the pancreatic allograft function. Surgery seems to be the best treatment option in the case of AVF or complete thrombosis of the allograft. Intravenous heparin followed by oral anticoagultion could be a conservative approach for SV thrombosis.

Notes: Abstract: The absolute cross section σ (E) of the radiative capture reaction p(7Be,γ)8B at the center-of-mass energy E = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H2 gas. The 8B residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a ΔE-E detector telescope. The 8B yield was observed concurrently with the 7Be + p elastic scattering yield, relating σ(E) to the Rutherford scattering cross section. The resulting value, σ(E) = 0.41 ± 0.11 μb, leads to an S(E) factor at zero energy of S(0) = 16 ± 4 eV b, in fair agreement with recommended values.

Notes: Abstract It is shown that the Partially Overlapping Molecular Level Model (POMLM) accounts for the experimental results of the dissipative28Si +48Ti collision around 210 MeV incident energy. The general trend of the properties of the fluctuations as well as the average angular distributions are reproduced by the same set of main parameters. A general consistency is also found between the present data and the data obtained in previous work on the same colliding system performed at lower incident energy (around 123 MeV).

Notes: Abstract The28Si+64Ni reaction at 163.8 MeV incident energy is studied by measuring in coincidenceγ-rays and charged particles identified from Z=2 to Z=16. The transition from quasi-elastic to more damped reactions is observed when the difference between the detected charge and the projectile one is increased. The strong influence of the particle decay on the measuredγ-ray multiplicity is evidenced with the help of the statistical model computer code CASCADE. Dissipative events are well described in the rolling limit with excitation energy equally shared between the fragments. The overall agreement is lost for the fragments with the projectile charge which show a small value of theγ-multiplicity even for dissipative events. This is probably connected with the previously observed non statistical behavior of gamma rays emitted in coincidence with projectile-like fragments. In the alpha-spectrum measured in coincidence with gamma-rays, the deexcitation of fused systems is clearly separated from in flight emission of deep inelastic fragments. The low measured gamma-ray multiplicity for fusion events is qualitatively explained taking into account the effect of alpha-emission in the statistical decay.