Catalytic reaction between adsorbed oxygen and hydrogen on Rh(111)

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Network Mutual Information and Synchronization under Time Transformations

We investigate the effect of general time transformations on the phase synchronization (PS) phenomenon and the mutual information rate (MIR) between pairs of nodes in dynamical networks. We demonstrate two important results concerning the invariance of both PS and the MIR. Under time transformations PS can neither be introduced nor destroyed and the MIR cannot be raised from zero. On the other hand, for proper time transformations the timing between the cycles of the coupled oscillators can be largely improved. Finally, we discuss the relevance of our findings for communication in dynamical networks.Comment: 15 p

Computer-guided concentration-controlled trials in autoimmune disorders

A randomized concentration-controlled clinical trial (RCCCT) is an alternate experimental design to the standard dose-controlled study. In a RCCCT, patients are randomly assigned to predefined plasma or blood drug concentration ranges (low, medium, and high). With the caveat that concentration ranges are sufficiently separated, this design should enhance the ability to discover important concentration response relationships. FK-506, a potent and promising immunosuppressive agent for prevention and treatment of graft rejection, has shown significant clinical activity in some immune-mediated disorders. To implement the RCCCT design, a novel FK-506 intelligent dosing system (IDS) was used to guide all doses to prospectively achieve the target concentration range specified in the study protocol. Patients enrolled in these trials suffered from a variety of autoimmune disorders, including multiple sclerosis, primary biliary cirrhosis, psoriasis, autoimmune chronic active hepatitis, and nephrotic syndrome. We observed excellent predictive performance of the IDS for all patients. The accuracy (mean prediction error) of the IDS was −0.022 ng/ml and the precision (standard deviation of the prediction error) was 0.119 ng/ml. Thus, the IDS is both accurate and reproducible for autoimmune patients. We conclude that the RCCCT design, guided by an accurate and precise IDS, is an informative and cost-effective approach for evaluation of efficacy and safety of effective but highly toxic agents. © 1993 Raven Press, Ltd., New York

Monoclonal gammopathy after intense induction immunosuppression in renal transplant patients

Objectives. Incidence and risk factors of post-transplant monoclonal gammopathy were studied in renal transplant patients who received their grafts between 1982 and 1992 (n=390 grafts). Immunoelectrophoresis was performed at annual intervals after transplantation. Results. Forty-six cases of clonal gammopathy were detected: 35 monoclonal, 11 bi- or triclonal, with a predominance of IgG and K light-chain subtypes (IgG, 39; IgA, 3; IgM, 4; K, 35; λ, 19). Gammopathy was transient in 17 patients (37%). The 5-year cumulative incidence of gammopathy was 10.7%, much higher than expected for a group of similar age from the general population. Thirty of the 46 gammopathies appeared within the first 2 years of transplantation. Gammopathy never progressed to multiple myeloma during follow-up (median 1 year; (range 0-10)); one patient subsequently developed Kaposi sarcoma. The 2-year incidence of gammopathy was much higher in patients transplanted in 1989-1991 (23/142) than in 1982-1988 (7/248) (P<0.0001). This coincided with the use of quadruple induction immunosuppression (cyclosporin A+azathioprine+prednisone plus either ATG-Fresenius (ATG-F) or OKT3) since 1989. The risk for acquiring gammopathy within 2 years of transplantation was 14.7% (95% CI 9.2, 20.3%) in patients receiving quadruple induction therapy, but only 3.0% (CI 1.2, 6.1%) without such therapy (P<0.0001). The risk for patients receiving quadruple immunosuppression with OKT3 was 24.5%, significantly greater than with ATG-F (11.8%, P<0.05). Discriminant analysis revealed that the type of immunosuppression, but not age or year of transplantation, were independent risk factors for gammopathy. Conclusions. Monoclonal gammopathy frequently occurs after renal transplantation. Risks are higher for patients receiving quadruple induction immunosuppression, particularly if it includes OKT3. Follow-up of these patients is warranted for the early detection of malignant transformatio

The backbone of the climate network

We propose a method to reconstruct and analyze a complex network from data generated by a spatio-temporal dynamical system, relying on the nonlinear mutual information of time series analysis and betweenness centrality of complex network theory. We show, that this approach reveals a rich internal structure in complex climate networks constructed from reanalysis and model surface air temperature data. Our novel method uncovers peculiar wave-like structures of high energy flow, that we relate to global surface ocean currents. This points to a major role of the oceanic surface circulation in coupling and stabilizing the global temperature field in the long term mean (140 years for the model run and 60 years for reanalysis data). We find that these results cannot be obtained using classical linear methods of multivariate data analysis, and have ensured their robustness by intensive significance testing.Comment: 6 pages, 5 figure

Pancreaticoduodenal transplantation in humans

Whole cadaveric pancreata were transplanted to the pelvic extraperitoneal location in four patients with diabetes who previously had undergone successful cadaveric renal transplantation. One graft was lost within a few hours from venous thrombosis but with patient survival. The other three are providing normal endocrine function after two and a half, 11 and 12 months. The exocrine pancreatic secretions were drained into the recipient jejunum through enteric anastomoses. Because mucosal slough of the graft and duodenum and jejunum in two patients caused a protein losing enteropathy and necessitated reoperations, we now do the pancreatic transplantation with only a blister of graft duodenum large enough for side-to-side enteroenterostomy. The spleen has been transplanted with the pancreas mainly for technical reasons, and this technique should have further trials in spite of the fact that delayed graft splenectomy became necessary in two recipients to treat graft induced hematologic complications

Millimeter-Wave Spectra, ab Initio Calculations, and Structures of Fluorophosphane and Chlorophosphane

The structures of fluorophosphane, PH2F, and chlorophosphane, PH2Cl, have been calculated ab initio at the SCF, MP2, CCSD, and CCSD(T) levels using a quadruple ζ polarized basis set. Equilibrium and ground state rotational constants as well as centrifugal distortion constants have been predicted for several isotopomers of PH2F and PH2Cl. Theoretical CCSD(T) geometries were also determined for the series of PHnX3-n (X = F, Cl; n = 0−3) molecules using a triple ζ polarized basis set. The millimeter-wave spectra of the short-lived molecules PH2F, PH2Cl, and their perdeuterated species were measured in the frequency range 100−470 GHz. For PH2F and PH2Cl, accurate ground state parameters have been obtained by a combined fit of the millimeter-wave data and the infrared ground state combination differences. The ro, rz, and re structures of PH2F and PH2Cl, as well as PH3, PCl3, and PHF2 have been determined. The experimental results are found in excellent agreement with their ab initio predictions