46 research outputs found
Distributed Change Detection via Average Consensus over Networks
Distributed change-point detection has been a fundamental problem when
performing real-time monitoring using sensor-networks. We propose a distributed
detection algorithm, where each sensor only exchanges CUSUM statistic with
their neighbors based on the average consensus scheme, and an alarm is raised
when local consensus statistic exceeds a pre-specified global threshold. We
provide theoretical performance bounds showing that the performance of the
fully distributed scheme can match the centralized algorithms under some mild
conditions. Numerical experiments demonstrate the good performance of the
algorithm especially in detecting asynchronous changes.Comment: 15 pages, 8 figure
Voriconazole and squamous cell carcinoma after lung transplantation: A multicenter study
This study evaluated the independent contribution of voriconazole to the development of squamous cell carcinoma (SCC) in lung transplant recipients, by attempting to account for important confounding factors, particularly immunosuppression. This international, multicenter, retrospective, cohort study included adult patients who underwent lung transplant during 2005-2008. Cox regression analysis was used to assess the effects of voriconazole and other azoles, analyzed as time-dependent variables, on the risk of developing biopsy-confirmed SCC. Nine hundred lung transplant recipients were included. Median follow-up time from transplant to end of follow-up was 3.51 years. In a Cox regression model, exposure to voriconazole alone (adjusted hazard ratio 2.39, 95% confidence interval 1.31-4.37) and exposure to voriconazole and other azole(s) (adjusted hazard ratio 3.45, 95% confidence interval 1.07-11.06) were associated with SCC compared with those unexposed after controlling for important confounders including immunosuppressants. Exposure to voriconazole was associated with increased risk of SCC of the skin in lung transplant recipients. Residual confounding could not be ruled out because of the use of proxy variables to control for some confounders. Benefits of voriconazole use when prescribed to lung transplant recipients should be carefully weighed versus the potential risk of SCC. This article is protected by copyright. All rights reserved
A review of bronchiolitis obliterans syndrome and therapeutic strategies
Lung transplantation is an important treatment option for patients with advanced lung disease. Survival rates for lung transplant recipients have improved; however, the major obstacle limiting better survival is bronchiolitis obliterans syndrome (BOS). In the last decade, survival after lung retransplantation has improved for transplant recipients with BOS. This manuscript reviews BOS along with the current therapeutic strategies, including recent outcomes for lung retransplantation
Management of multidrug resistant Gram-negative bacilli infections in solid organ transplant recipients: SET/GESITRA-SEIMC/REIPI recommendations
Solid organ transplant (SOT) recipients are especially at risk of developing infections by multidrug resistant (MDR) Gram-negative bacilli (GNB), as they are frequently exposed to antibiotics and the healthcare setting, and are regulary subject to invasive procedures. Nevertheless, no recommendations concerning prevention and treatment are available. A panel of experts revised the available evidence; this document summarizes their recommendations: (1) it is important to characterize the isolate´s phenotypic and genotypic resistance profile; (2) overall, donor colonization should not constitute a contraindication to transplantation, although active infected kidney and lung grafts should be avoided; (3) recipient colonization is associated with an increased risk of infection, but is not a contraindication to transplantation; (4) different surgical prophylaxis regimens are not recommended for patients colonized with carbapenem-resistant GNB; (5) timely detection of carriers, contact isolation precautions, hand hygiene compliance and antibiotic control policies are important preventive measures; (6) there is not sufficient data to recommend intestinal decolonization; (7) colonized lung transplant recipients could benefit from prophylactic inhaled antibiotics, specially for Pseudomonas aeruginosa; (8) colonized SOT recipients should receive an empirical treatment which includes active antibiotics, and directed therapy should be adjusted according to susceptibility study results and the severity of the infection.J.T.S. holds a research contract from the Fundación para la Formación e Investigación de los Profesionales de la Salud de Extremadura (FundeSalud), Instituto de Salud Carlos III. M.F.R. holds a clinical research contract “Juan Rodés” (JR14/00036) from the Spanish Ministry of Economy and Competitiveness, Instituto de Salud Carlos III
Optimal and asymptotically optimal cusum rules for change point detection in the Brownian motion model with multiple alternatives
This work examines the problem of sequential change detection in the constant drift of a Brownian motion in the case of multiple alternatives. As a performance measure an extended Lorden's criterion is proposed. When the possible drifts, assumed after the change, have the same sign, the CUSUM rule, designed to detect the smallest in absolute value drift, is proven to be the optimum. If the drifts have opposite signs, then a specific 2-CUSUM rule is shown to be asymptotically optimal as the frequency of false alarms tends to infinity
ROBUSTNESS OF THE N-CUSUM STOPPING RULE IN A WIENER DISORDER PROBLEM
We study a Wiener disorder problem of detecting the minimum of
change-points in observation channels coupled by correlated noises. It is
assumed that the observations in each dimension can have different strengths
and that the change-points may differ from channel to channel. The objective is
the quickest detection of the minimum of the change-points. We adopt a
min-max approach and consider an extended Lorden's criterion, which is
minimized subject to a constraint on the mean time to the first false alarm. It
is seen that, under partial information of the post-change drifts and a general
nonsingular stochastic correlation structure in the noises, the minimum of
cumulative sums (CUSUM) stopping rules is asymptotically optimal as the mean
time to the first false alarm increases without bound. We further discuss
applications of this result with emphasis on its implications to the efficiency
of the decentralized versus the centralized systems of observations which arise
in engineering.Comment: Published at http://dx.doi.org/10.1214/14-AAP1078 in the Annals of
Applied Probability (http://www.imstat.org/aap/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Interaction of thiamine and its phosphate esters with Pt(II) and Pd(II)
The reactions of Thiamine·HCl (ThH), Thiamine monophosphate·HCl (TMP) and Thiamine pyrophosphate (TPP) have been studied in aqueous solutions (pH ∼3-4) at room temperature. Two types of complexes have been characterized by elemental analyses, conductivity measurements, ir, 1H nmr and 13C nmr spectra:. ionic 1:2 sults in which thiamine is present as a cation, and 1:1 complexes in which the organic ligand is directly coordinated to the metal ions. The formulae of the ionic salts that were prepared are [MX4]2-[Th]+2 and MThX3. The salts can easily be converted into 1:1 products by stirring in water at room temperature, while the TPP analogs require excess of ligand. The 1:1 complexes appear to have a zwitterionic structure and the metal is bound through N′1 of the pyrimidine ring of thiamine. These solid and stable complexes of thinmine are the first examples reported having a direct metal-to-nitrogen bond. © 1977
Interaction of thiamine and its phosphate esters with Pt(II) and Pd(II)
The reactions of Thiamine·HCl (ThH), Thiamine monophosphate·HCl (TMP) and Thiamine pyrophosphate (TPP) have been studied in aqueous solutions (pH ∼3-4) at room temperature. Two types of complexes have been characterized by elemental analyses, conductivity measurements, ir, 1H nmr and 13C nmr spectra:. ionic 1:2 sults in which thiamine is present as a cation, and 1:1 complexes in which the organic ligand is directly coordinated to the metal ions. The formulae of the ionic salts that were prepared are [MX4]2-[Th]+2 and MThX3. The salts can easily be converted into 1:1 products by stirring in water at room temperature, while the TPP analogs require excess of ligand. The 1:1 complexes appear to have a zwitterionic structure and the metal is bound through N′1 of the pyrimidine ring of thiamine. These solid and stable complexes of thinmine are the first examples reported having a direct metal-to-nitrogen bond. © 1977