189 research outputs found

    Dealing with Interval Scale Data in Data Envelopment Analysis

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    This papaer considers the problem of interval scale data in the most widely used models of Data Envelopment Analysis (DEA), the CCR, and the BCC models. Radial models require inputs and outputs measured on the ratio scale. Our focus is on how to deal with interval scale variables especially when the interval scale variable is a difference of two ratio scale variables like profit or the decrease/increase in bank accounts. Using these ratio scale variables as variables in the DEA model we suggest radial models. An approach to how to deal with interval scale variables when we relax the radiality assumption is also discussed

    Lyman-α\alpha polarization from cosmological ionization fronts: II. Implications for intensity mapping

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    This is the second paper in a series whose aim is to predict the power spectrum of intensity and polarized intensity from cosmic reionization fronts. After building the analytic models for intensity and polarized intensity calculations in paper I, here we apply these models to simulations of reionization. We construct a geometric model for identifying front boundaries, calculate the intensity and polarized intensity for each front, and compute a power spectrum of these results. This method was applied to different simulation sizes and resolutions, so we ensure that our results are convergent. We find that the power spectrum of fluctuations at z=8z=8 in a bin of width Δz=0.5\Delta z=0.5 (λ/Δλ=18\lambda/\Delta\lambda=18) is Δℓ≡[ℓ(ℓ+1)Cℓ/2π]1/2\Delta_\ell \equiv [\ell(\ell+1)C_\ell/2\pi]^{1/2} is 3.2×10−113.2\times 10^{-11} erg s−1^{-1} cm−2^{-2} sr−1^{-1} for the intensity II, 7.6×10−137.6\times10^{-13} erg s−1^{-1} cm−2^{-2} sr−1^{-1} for the EE-mode polarization, and 5.8×10−135.8\times10^{-13} erg s−1^{-1} cm−2^{-2} sr−1^{-1} for the BB-mode polarization at ℓ=1.5×104\ell=1.5\times10^4. After computing the power spectrum, we compare results to detectable scales and discuss implications for observing this signal based on a proposed experiment. We find that, while fundamental physics does not exclude this kind of mapping from being attainable, an experiment would need to be highly ambitious and require significant advances to make mapping Lyman-α\alpha polarization from cosmic reionization fronts a feasible goal.Comment: 18 pages, 9 figures, to be submitted to JCA

    Lyman-{\alpha} polarization from cosmological ionization fronts: I. Radiative transfer simulations

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    In this paper, we present the formalism of simulating Lyman-α\alpha emission and polarization around reionization (zz = 8) from a plane-parallel ionization front. We accomplish this by using a Monte Carlo method to simulate the production of a Lyman-α\alpha photon, its propagation through an ionization front, and the eventual escape of this photon. This paper focuses on the relation of the input parameters of ionization front speed UU, blackbody temperature TbbT_{\rm bb}, and neutral hydrogen density nHIn_{\rm HI}, on intensity II and polarized intensity PP as seen by a distant observer. The resulting values of intensity range from 3.18×10−143.18\times 10^{-14} erg/cm2^{2}/s/sr to 1.96×10−91.96 \times 10^{-9} erg/cm2^{2}/s/sr , and the polarized intensity ranges from 5.73×10−175.73\times 10^{-17} erg/cm2^{2}/s/sr to 5.31×10−125.31 \times 10^{-12} erg/cm2^{2}/s/sr. We found that higher TbbT_{\rm bb}, higher UU, and higher nHIn_{\rm HI} contribute to higher intensity, as well as polarized intensity, though the strongest dependence was on the hydrogen density. The dependence of viewing angle of the front is also explored. We present tests to support the validity model, which makes the model suitable for further use in a following paper where we will calculate the intensity and polarized intensity power spectrum on a full reionization simulation.Comment: 29 pages, 13 figures, to be submitted to JCA

    Structural characterization of EGFR exon 19 deletion mutation using molecular dynamics simulation

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    Epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor important in diverse biological processes including cell proliferation and survival. Upregulation of EGFR activity due to over-expression or mutation is widely implicated in cancer. Activating somatic mutations of the EGFR kinase are postulated to affect the conformation and/or stability of the protein, shifting the EGFR inactive-active state equilibrium towards the activated state. Here, we examined a common EGFR deletion mutation, Δ746ELREA750, which is frequently observed in non-small cell lung cancer patients. By using molecular dynamics simulation, we investigated the structural effects of the mutation that lead to the experimentally reported increases in kinase activity. Simulations of the active form wild-type and ΔELREA EGFRs revealed the deletion stabilizes the αC helix of the kinase domain, which is located adjacent to the deletion site, by rigidifying the flexible ÎČ3-αC loop that accommodates the ELREA sequence. Consequently, the αC helix is stabilized in the “αC-in” active conformation that would prolong the time of the activated state. Moreover, in the mutant kinase, a salt bridge between E762 and K745, which is key for EGFR activity, was also stabilized during the simulation. Additionally, the interaction between EGFR and ATP was favored by ΔELREA EGFR over wild-type EGFR, as reflected by the number of hydrogen bonds formed and the free energy of binding. Simulation of inactive EGFR suggested the deletion would promote a shift from the inactive conformation towards active EGFR, which is supported by the inward movement of the αC helix. The MDS results also align with the effects of tyrosine kinase inhibitors on ΔELREA and wild-type EGFR lung cancer cell lines, where more pronounced inhibition was observed against ΔELREA than for wild-type EGFR by inhibitors recognizing the active kinase conformation.</p

    Polyneuropathy monitoring in Parkinson's disease patients treated with levodopa/carbidopa intestinal gel

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    Objectives Levodopa-carbidopa-intestinal-gel (LCIG) infusion is an effective treatment for advanced PD with motor fluctuations. Polyneuropathy occurs as a complication in 10-15% of patients. We wanted to assess the frequency of polyneuropathy in Finnish advanced Parkinson's disease (PD) patients with continuous LCIG infusion, and the value of different clinical monitoring parameters during follow-up. Materials and methods Patient records of PD patients started on LCIG infusion at Helsinki University Hospital who received nerve conduction studies at baseline and 6 months after treatment initiation were reviewed for epidemiological information, mini mental state examination, baseline and 6 months' UPRDS-III, weight, body mass index, levodopa dose (LD), plasma homocysteine levels, folate, vitamin B6 and B12. Results Out of 19 patients (n = 6 on B-vitamin substitution), two (10.5%) developed new-onset polyneuropathy after initiation of LCIG therapy (n = 0 with vitamin substitution). Neuropathy was associated with significant weight loss (BMI reduction > 1.5), but not with other monitoring parameters. Homocysteine rose significantly in patients not substituted with B-vitamin complex, but not in patients with B-vitamin substitution. Homocysteine changes correlated with LD changes in the absence of vitamin B substitution. After oral B-vitamin substitution, both patients' polyneuropathy remained electrophysiologically and clinically stable. Conclusions Rates of polyneuropathy in Finnish PD patients with LCIG treatment are comparable to previous studies. Patients' weight should be included in regular follow up monitoring and can be used for patient self-monitoring. Vitamin B substitution appears to reduce coupling between levodopa dose and homocysteine and may be useful to prevent polyneuropathy related to LCIG.Peer reviewe

    Evolutionary multi-stage financial scenario tree generation

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    Multi-stage financial decision optimization under uncertainty depends on a careful numerical approximation of the underlying stochastic process, which describes the future returns of the selected assets or asset categories. Various approaches towards an optimal generation of discrete-time, discrete-state approximations (represented as scenario trees) have been suggested in the literature. In this paper, a new evolutionary algorithm to create scenario trees for multi-stage financial optimization models will be presented. Numerical results and implementation details conclude the paper

    Evaluation of Circulating Cardiovascular Biomarker Levels for Early Detection of Congenital Heart Disease in Newborns in Sweden

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    Congenital heart disease (CHD) is the most common congenital malformation in humans worldwide. Circulating cardiovascular biomarkers could potentially improve the early detection of CHD, even in asymptomatic newborns.\nTo assess the performance of a dried blood spot (DBS) test to measure the cardiovascular biomarker amino terminal fragment of the prohormone brain-type natriuretic peptide (NT-proBNP) levels in newborns and to compare DBS with standard EDTA analysis in control newborns during the first week of life.\nThis diagnostic study was conducted in a single regional pediatric service in southern Sweden. Healthy, term neonates born between July 1, 2018, and May 31, 2019, were prospectively enrolled and compared against retrospectively identified newborns with CHD born between September 1, 2003, and September 30, 2019. Neonates who required inpatient treatment beyond the standard postnatal care were excluded.\nNew DBS test for NT-proBNP quantification in newborns that used 3 ÎŒL of blood vs the current screening standard.\nPerformance of the new test and when combined with pulse oximetry screening was measured by receiver operating characteristic curve analysis. Performance of the new test and EDTA screening was compared using Pearson linear correlation analysis.\nThe DBS samples of 115 neonates (81 control newborns and 34 newborns with CHD, of whom 63 were boys [55%] and the mean [SD] gestational age was 39.6 [1.4] weeks) were analyzed. The new NT-proBNP test alone identified 71% (n = 24 of 34) of all CHD cases and 68% (n = 13 of 19) of critical CHD cases as soon as 2 days after birth. Detection of any CHD type improved to 82% (n = 28 of 34 newborns) and detection of critical CHD improved to 89% (n = 17 of 19 newborns) when combined pulse oximetry screening and NT-proBNP test results were used. Performance of the NT-proBNP test was excellent when control newborns were matched to newborns with CHD born between July 1, 2018, and May 31, 2019 (area under the curve, 0.96; SE, 0.027; 95% CI, 0.908-1.0; asymptotic P < .05).\nThis study found that NT-proBNP assay using minimal DBS samples appears to be timely and accurate in detecting CHD in newborns and to discriminate well between healthy newborns and newborns with various types of CHD. This finding warrants further studies in larger cohorts and highlights the potential of NT-proBNP to improve neonatal CHD screening.\nImportance\nObjectives\nDesign, Setting, and Participants\nExposure\nMain Outcomes and Measures\nResults\nConclusions and Relevanc

    Adalimumab and sulfasalazine in alleviating sacroiliac and aortic inflammation detected in PET/CT in patients with axial spondyloarthritis : PETSPA

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    Publisher Copyright: © 2021 The Authors. Immunity, Inflammation and Disease published by John Wiley & Sons Ltd.Aim: Inflammatory signals in the sacroiliac (SI) joints and the aorta of patients with axial spondyloarthritis (axSpA) were graded by positron emission tomography/computed tomography (PET/CT) imaging before and after treatment with sulfasalazine (SSZ) or adalimumab (ADA). Methods: Patients with axSpA, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≄ 4, were recruited. Disease-modifying antirheumatic drug-naĂŻve patients started SSZ for 12 weeks, whereas those with prestudy treatment with or contraindication to SSZ commenced ADA for 16 weeks. In addition, those patients in the SSZ group with insufficient response commenced ADA for 16 weeks. 18F-fluorodeoxyglucose PET/CT was performed after inclusion and after treatment with SSZ and ADA. Maximum standardized uptake value (SUVmax) was assessed for the aorta and the SI joints, and maximal target-to-blood-pool ratio (TBRmax) only for the aorta. Results: Among five SSZ patients, mean ± SD BASDAI was 4.7 ± 1.6 before and 3.5 ± 1.4 after treatment (p =.101). In 13 ADA patients, the BASDAI decreased from 5.4 ± 1.6 to 2.8 ± 2.2 (p <.001). Among the SSZ patients, SUVmax in SI joints decreased from 2.35 ± 0.55 to 1.51 ± 0.22 (−35.8%, p =.029). Aortic TBRmax decreased from 1.59 ± 0.43 to 1.26 ± 0.26 (−33.2%, p =.087). In the ADA patients, SUVmax in the SI joints was 1.92 ± 0.65 before and 1.88 ± 0.54 after treatment (−1.8%, p =.808) and TBRmax in the aorta 1.50 ± 0.60 before and 1.40 ± 0.26 after treatment (−6.7%, p =.485). Conclusions: Our small open-label study showed that SSZ may reduce PET-CT-detectable inflammation in the SI joints, with a trend towards a reduction in the aorta.Peer reviewe

    The Hard Life: A Pedagogical Experience in Industrial Design

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    Thispaperseekstoanalyzeanddiscussaredesignprojectdeveloped by students of master’s degree in industrial design. Based on the book The Hard Life, from English designer Jasper Morrison, the briefing proposed the devel- opment of concepts for new products inspired by the selection of objects in the book, and respective written interpretations. It seeks to explore the dialogue between the original objects – their use, Morrison’s interpretation - and the reinterpretation made by the students considering the current material culture. Accompanied and coordinated with Bisarro, contemporary studio dedicated to the artisan production of small series in Bisalhães black clay, UNESCO Immaterial Cultural Heritage, the project seeks to explore the boundaries and common ground between memory and contemporary times. More than the results, it is intended to discuss proposals and approaches, from functional interpretations, formal inspiration, to the appropriation of affordance and gesture.info:eu-repo/semantics/publishedVersio
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