1,687 research outputs found
Exponential instability in the fractional Calder\'on problem
In this note we prove the exponential instability of the fractional
Calder\'on problem and thus prove the optimality of the logarithmic stability
estimate from \cite{RS17}. In order to infer this result, we follow the
strategy introduced by Mandache in \cite{M01} for the standard Calder\'on
problem. Here we exploit a close relation between the fractional Calder\'on
problem and the classical Poisson operator. Moreover, using the construction of
a suitable orthonormal basis, we also prove (almost) optimality of the Runge
approximation result for the fractional Laplacian, which was derived in
\cite{RS17}. Finally, in one dimension, we show a close relation between the
fractional Calder\'on problem and the truncated Hilbert transform.Comment: 17 page
Phosphorus in manure and sewage sludge more recyclable than in soluble inorganic fertilizer
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Value Efficiency Analysis for Incorporating Preference Information in Data Envelopment Analysis
We develop a procedure and the requisite theory for incorporating preference information in a novel way in the efficiency analysis of Decision Making Units. The efficiency of Decision Making Units is defined in the spirit of Data Envelopment Analysis (DEA), complemented with Decision Maker's preference information concerning the desirable structure of inputs and outputs. Our procedure begins by aiding the Decision Maker in searching for the most preferred combination of inputs and outputs of Decision Making Units (for short, Most Preferred Solution) which are efficient in DEA. Then, assuming that the Decision Maker's Most Preferred Solution maximizes his/her underlying (unknown) value function at the moment when the search is terminated, we approximate the indifference contour of the value function at this point with its possible tangent hyperplanes. Value Efficiency scores are then calculated for each Decision Making Unit comparing the inefficient units to units having the same value as the Most Preferred Solution. The resulting Value Efficiency scores are optimistic approximations of the true scores. The procedure and the resulting efficiency scores are immediately applicable to solving practical problems
Sequential double cross-validation for assessment of added predictive ability in high-dimensional omic applications
Enriching existing predictive models with new biomolecular markers is an important task in the new multi-omic era. Clinical studies increasingly include new sets of omic measurements which may prove their added value in terms of predictive performance. We introduce a two-step approach for the assessment of the added predictive ability of omic predictors, based on sequential double cross-validation and regularized regression models. We propose several performance indices to summarize the two-stage prediction procedure and a permutation test to formally assess the added predictive value of a second omic set of predictors over a primary omic source. The performance of the test is investigated through simulations. We illustrate the new method through the systematic assessment and comparison of the performance of transcriptomics and metabolomics sources in the prediction of body mass index (BMI) using longitudinal data from the Dietary, Lifestyle, and Genetic determinants of Obesity and Metabolic syndrome (DILGOM) study, a population-based cohort from Finland
Collagen XVII promotes integrin-mediated squamous cell carcinoma transmigration – a novel role for alphaIIb integrin and tirofiban
Allocating Logging Rights in Peruvian Amazonia-Does It Matter to Be Local?
Conclusions/Significance: The allocation process left a considerable number of forest areas under the management of small and local actors, and if Peru is to reach its goal of zero deforestation rate by safeguarding 75 per cent of its forests by 2020, the small and the local actors need to be integrated to the forest regime as important constituents of its legitimacy
Antidepressant use and work-related injuries
Background. Adverse effects of antidepressants are most common at the beginning of the treatment, but possible also later. We examined the association between antidepressant use and work-related injuries taking into account the duration of antidepressant use. Method. Antidepressant use and work-related injuries between 2000 and 2011 were measured among 66 238 employees (mean age 43.8 years, 80% female) using linkage to national records (the Finnish Public Sector study). We analysed data using time-dependent modelling with individuals as their own controls (self-controlled case-series design). Results. In 2238 individuals who had used antidepressants and had a work-related injury during a mean follow-up of 7.8 years, no increase in the risk of injury was observed in the beginning of antidepressant treatment. However, an increased injury risk was seen after 3 months of treatment (rate ratio, compared with no recent antidepressant use, 1.27, 95% confidence interval 1.10-1.48). This was also the case among those who had used only selective serotonin re-uptake inhibitors (n = 714; rate ratio 1.41, 95% confidence interval 1.08-1.83). Conclusions. Antidepressant use was not associated with an increased risk of work-related injury at the beginning of treatment. Post-hoc analyses of antidepressant trials are needed to determine whether long-term use of antidepressants increases the risk of work-related injury.Peer reviewe
Acidic cysteine endoproteinase cathepsin K in the degeneration of the superficial articular hyaline cartilage in osteoarthritis
Peer reviewe
Early retirement from work among employees with a diagnosis of personality disorder compared to anxiety and depressive disorders
Objective:Â Risk of retirement from work before statutory retirement age among employees with personality disorders is unknown.Method:Â We used diagnoses of awarded medical rehabilitations and hospitalisations to select two clinical cohorts from a population of 151,618 employees: participants in rehabilitation (total N=1942, 233 personality disorder, 419 anxiety disorder and 1290 depression cases) and hospitalised patients (N=1333, 354, 126 and 853, respectively). Early retirement from work was tracked through national registers during a period of 5 years. Cox proportional hazard models were used to examine the association of diagnostic groups with risk of early retirement.Results:Â In models adjusted for age, sex and socioeconomic position, the relative risk of early retirement for patients with personality disorders was 3.5-fold (95% CI 2.1 to 5.8) in the rehabilitation cohort and 2.3-fold (95% CI 1.6 to 3.5) in the hospital cohort compared with anxiety disorders. The corresponding hazard ratios of early retirement for personality disorders compared with depressive disorders were 1.1 (95% CI 0.8-1.5) and 1.7 (95% CI 1.4-2.1), respectively.Conclusions:Â Personality disorders increase the risk of early retirement at least to an equal extent as depression and more than twice that of anxiety disorders.</p
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