190 research outputs found

    MaxSkew and MultiSkew: Two R Packages for Detecting, Measuring and Removing Multivariate Skewness

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    Skewness plays a relevant role in several multivariate statistical techniques. Sometimes it is used to recover data features, as in cluster analysis. In other circumstances, skewness impairs the performances of statistical methods, as in the Hotelling's one-sample test. In both cases, there is the need to check the symmetry of the underlying distribution, either by visual inspection or by formal testing. The R packages MaxSkew and MultiSkew address these issues by measuring, testing and removing skewness from multivariate data. Skewness is assessed by the third multivariate cumulant and its functions. The hypothesis of symmetry is tested either nonparametrically, with the bootstrap, or parametrically, under the normality assumption. Skewness is removed or at least alleviated by projecting the data onto appropriate linear subspaces. Usages of MaxSkew and MultiSkew are illustrated with the Iris dataset

    Block preconditioning for fault/fracture mechanics saddle-point problems

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    The efficient simulation of fault and fracture mechanics is a key issue in several applications and is attracting a growing interest by the scientific community. Using a formulation based on Lagrange multipliers, the Jacobian matrix resulting from the Finite Element discretization of the governing equations has a non-symmetric generalized saddlepoint structure. In this work, we propose a family of block preconditioners to accelerate the convergence of Krylov methods for such problems. We critically review possible advantages and difficulties of using various Schur complement approximations, based on both physical and algebraic considerations. The proposed approaches are tested in a number of real-world applications, showing their robustness and efficiency also in large-size and ill-conditioned problems

    High Density Lipoproteins Inhibit Oxidative Stress-Induced Prostate Cancer Cell Proliferation

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    Recent evidence suggests that oxidative stress can play a role in the pathogenesis and the progression of prostate cancer (PCa). Reactive oxygen species (ROS) generation is higher in PCa cells compared to normal prostate epithelial cells and this increase is proportional to the aggressiveness of the phenotype. Since high density lipoproteins (HDL) are known to exert antioxidant activities, their ability to reduce ROS levels and the consequent impact on cell proliferation was tested in normal and PCa cell lines. HDL significantly reduced basal and H2O2-induced oxidative stress in normal, androgen receptor (AR)-positive and AR-null PCa cell lines. AR, scavenger receptor BI and ATP binding cassette G1 transporter were not involved. In addition, HDL completely blunted H2O2-induced increase of cell proliferation, through their capacity to prevent the H2O2-induced shift of cell cycle distribution from G0/G1 towards G2/M phase. Synthetic HDL, made of the two main components of plasma-derived HDL (apoA-I and phosphatidylcholine) and which are under clinical development as anti-atherosclerotic agents, retained the ability of HDL to inhibit ROS production in PCa cells. Collectively, HDL antioxidant activity limits cell proliferation induced by ROS in AR-positive and AR-null PCa cell lines, thus supporting a possible role of HDL against PCa progression

    Comparing quality profiles in Human-Robot Collaboration: empirical evidence in the automotive sector

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    Purpose: Human-Robot Collaboration (HRC) is a paradigm that is gradually consolidating in the industrial field. The goal of this paradigm is to combine human and robot skills to make production more flexible. An effective implementation of HRC requires a careful analysis of its different aspects, related to both robots and humans. For this reason, the development of a tool able to consider all HRC aspects to evaluate the collaboration quality is a real practical need. Design/methodology/approach: In a previous work, Gervasi et al. (2020) proposed a multidimensional framework to evaluate HRC quality. This framework has been tested on a real industrial HRC application in the automotive sector. Two different alternatives of the same assembly task were analyzed and compared on the quality reference framework. Findings: The comparison between the two alternatives of the same assembly task highlighted the framework's ability to detect the effects of different configurations on the various HRC dimensions. This ability can be useful in decision making processes and in improving the collaboration quality. Social implications: The framework considers the human aspects related to the interaction with robots, allowing to effectively monitor and improve the collaboration quality and operator satisfaction. Originality/value: This paper extends and shows the use of the HRC evaluation framework proposed by Gervasi et al. (2020) on real industrial applications. In addition, an HRC application implemented in an important automotive company is described and analyzed in detail

    Protocetraric and Salazinic Acids as Potential Inhibitors of SARS-CoV-2 3CL Protease: Biochemical, Cytotoxic, and Computational Characterization of Depsidones as Slow-Binding Inactivators

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    The study investigated the inhibitory activity of protocetraric and salazinic acids against SARS-CoV-2 3CL(pro). The kinetic parameters were determined by microtiter plate-reading fluorimeter using a fluorogenic substrate. The cytotoxic activity was tested on murine Sertoli TM4 cells. In silico analysis was performed to ascertain the nature of the binding with the 3CL(pro). The compounds are slow-binding inactivators of 3CL(pro) with a K(i) of 3.95 ÎŒM and 3.77 ÎŒM for protocetraric and salazinic acid, respectively, and inhibitory efficiency k(inact)/K(i) at about 3 × 10(−5) s(−1)”M(−1). The mechanism of inhibition shows that both compounds act as competitive inhibitors with the formation of a stable covalent adduct. The viability assay on epithelial cells revealed that none of them shows cytotoxicity up to 80 ÎŒM, which is well below the K(i) values. By molecular modelling, we predicted that the catalytic Cys145 makes a nucleophilic attack on the carbonyl carbon of the cyclic ester common to both inhibitors, forming a stably acyl-enzyme complex. The computational and kinetic analyses confirm the formation of a stable acyl-enzyme complex with 3CL(pro). The results obtained enrich the knowledge of the already numerous biological activities exhibited by lichen secondary metabolites, paving the way for developing promising scaffolds for the design of cysteine enzyme inhibitors

    The European Large Area ISO Survey IX: the 90 micron luminosity function from the Final Analysis sample

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    We present the 90 micron luminosity function of the Final Analysis of the European Large Area ISO Survey (ELAIS), extending the sample size of our previous analysis (paper IV) by about a factor of 4. Our sample extends to z=1.1, around 50 times the comoving volume of paper IV, and 10^{7.7} < h^{-2}L/Lsun < 10^{12.5}. From our optical spectroscopy campaigns of the northern ELAIS 90 mircon survey (7.4 deg^2 in total, to S(90um)>70mJy), we obtained redshifts for 61% of the sample (151 redshifts) to B<21 identified at 7 microns, 15 microns, 20cm or with bright (B<18.5) optical identifications. The selection function is well-defined, permitting the construction of the 90 micron luminosity function of the Final Analysis catalogue in the ELAIS northern fields, which is in excellent agreement with our Preliminary Analysis luminosity function in the ELAIS S1 field from paper IV. The luminosity function is also in good agreement with the IRAS-based prediction of Serjeant & Harrison (2004), which if correct requires luminosity evolution of (1+z)^{3.4 +/- 1.0} for consistency with the source counts. This implies an evolution in comoving volume averaged star formation rate at z<~1 consistent with that derived from rest-frame optical and ultraviolet surveys.Comment: MNRAS accepted. 7 pages, 5 figures. Uses BoxedEPS (included

    Pneumocystis jirovecii pneumonia in patients with decompensated cirrhosis: a case series

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    Objectives: Pneumocystis jirovecii pneumonia (PCP) incidence is increasing in people without HIV. Decompensated liver cirrhosis is not currently considered a risk factor for PCP. The aim of this paper is to describe a case series of patients with decompensated liver cirrhosis and PCP. Methods: All consecutive patients hospitalized with decompensated cirrhosis and microbiology-confirmed PCP at Policlinico Modena University Hospital from January 1, 2016 to December 31, 2021 were included in our series. Results: Eight patients were included. All patients had advanced-stage liver disease with a model for end-stage liver disease score above 15 (6/8 above 20). Four were on an active orthotopic liver transplant waiting list at the time of PCP diagnosis. Five patients did not have any traditional risk factor for PCP, whereas the other three were on glucocorticoid treatment for acute-on-chronic liver failure. All patients were treated with cotrimoxazole, except two who died before the diagnosis. Five patients died (62.5%), four of them within 30 days from PCP diagnosis. Of the remaining three, one patient underwent liver transplantation. Conclusion: Although further studies are needed, liver cirrhosis can be an independent risk factor for PCP in patients with decompensated cirrhosis that is mainly due to severe alcoholic hepatitis and who are on corticosteroids therapy, and primary prophylaxis for PCP should be considered

    GWAS for male-pattern baldness identifies 71 susceptibility loci explaining 38% of the risk

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    Male pattern baldness (MPB) or androgenetic alopecia is one of the most common conditions affecting men, reaching a prevalence of similar to 50% by the age of 50; however, the known genes explain little of the heritability. Here, we present the results of a genome-wide association study including more than 70,000 men, identifying 71 independently replicated loci, of which 30 are novel. These loci explain 38% of the risk, suggesting that MPB is less genetically complex than other complex traits. We show that many of these loci contain genes that are relevant to the pathology and highlight pathways and functions underlying baldness. Finally, despite only showing genome-wide genetic correlation with height, pathway-specific genetic correlations are significant for traits including lifespan and cancer. Our study not only greatly increases the number of MPB loci, illuminating the genetic architecture, but also provides a new approach to disentangling the shared biological pathways underlying complex diseases

    Pre-treatment risk factors to predict early cisplatin-related nephrotoxicity in locally advanced head and neck cancer patients treated with chemoradiation: A single Institution experience

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    Objectives: Cisplatin is essential in the curative treatment of locally advanced head and neck squamous cell carcinoma (LA-HNSCC) patients. The assessment of risk factors to predict an early cisplatin-induced nephrotoxicity could help in better managing one of the most relevant cisplatin-related dose-limiting factors. Material and methods: We retrospectively collected data of LA-HNSCC patients treated at our Institution from 2008 to 2019. Patients received cisplatin in a curative setting concurrently with radiation. Acute Kidney Injury (AKI) was assessed as a dichotomous variable (CreaIncr) based on pre-treatment values, and values recorded at days 6-20 post-first cycle of cisplatin. Univariable logistic regression models were performed to investigate associations between CreaIncr and clinical characteristics. A multivariable logistic model on a priori selected putative covariates was performed. Results: Of the 350 LA-HNSCC treated patients, 204 were analyzed. Ninety (44 %) suffered from any grade AKI (grade I 51.1 %): out of them, 84.4 % received high-dose cisplatin (100 mg/m2 q21). On the univariable logistic regression model, male sex, age, serum uric acid, creatinine, concomitant drugs, and cisplatin schedule were significantly associated with a higher rate of AKI. At multivariable model, age (p = 0.034), baseline creatinine (p = 0.027), concomitant drugs (p = 0.043), and cisplatin schedule (one-day bolus or fractionated high-dose vs. weekly; p = 0.001) maintained their significant association. Conclusions: Identifying pre-treatment risk factors in LA-HNSCC patients may improve decision-making in a setting where cisplatin has a curative significance. A strict monitoring of AKI could avoid cisplatin dose adjustments, interruptions, and treatment delays, thus limiting a negative impact on outcomes

    Digital PCR improves the quantitation of DMR and the selection of CML candidates to TKIs discontinuation

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    Treatment-free remission (TFR) by tyrosine kinase inhibitors (TKI) discontinuation in patients with deep molecular response (DMR) is a paramount goal in the current chronic myeloid leukemia (CML) therapeutic strategy. The best DMR level by real-time quantitative PCR (RT-qPCR) for TKI discontinuation is still a matter of debate. To compare the accuracy of digital PCR (dPCR) and RT-qPCR for BCR-ABL1 transcript levels detection, 142 CML patients were monitored for a median time of 24\ua0months. Digital PCR detected BCR-ABL1 transcripts in the RT-qPCR undetectable cases. The dPCR analysis of the samples, grouped by the MR classes, revealed a significant difference between MR4.0 and MR4.5 (P\ua0=\ua00.0104) or MR5.0 (P\ua0=\ua00.0032). The clinical and hematological characteristics of the patients grouped according to DMR classes (MR4.0 vs MR4.5-5.0 ) were superimposable. Conversely, patients with dPCR values <0.468 BCR-ABL1 copies/\ub5L (as we previously described) showed a longer DMR duration (P\ua0=\ua00.0220) and mainly belonged to MR4.5-5.0 (P\ua0=\ua00.0442) classes compared to patients with higher dPCR values. Among the 142 patients, 111 (78%) discontinued the TKI treatment; among the 111 patients, 24 (22%) lost the MR3.0 or MR4.0 . RT-qPCR was not able to discriminate patients with higher risk of MR loss after discontinuation (P\ua0=\ua00.8100). On the contrary, according to dPCR, 12/25 (48%) patients with BCR-ABL1 values 650.468 and 12/86 (14%) patients with BCR-ABL1 values <0.468 lost DMR in this cohort, respectively (P\ua0=\ua00.0003). Treatment-free remission of patients who discontinued TKI with a dPCR <0.468 was significantly higher compared to patients with dPCR\ua0 65\ua00.468 (TFR at 2\ua0years 83% vs 52% P\ua0=\ua00.0017, respectively). In conclusion, dPCR resulted in an improved recognition of stable DMR and of candidates to TKI discontinuation
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