1,117 research outputs found

    Quantiles for Fractions and Other Mixed Data

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    This paper studies the estimation of quantile regression for fractional data, focusing on the case where there are mass-points at zero or/and one. More generally, we propose a simple strategy for the estimation of the conditional quantiles of data from mixed distributions, which combines standard results on the estimation of censored and Box-Cox quantile regressions. The implementation of the proposed method is illustrated using a well-known dataset.

    Quantiles for Fractions and Other Mixed Data

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    This paper studies the estimation of quantile regression for fractional data, focusing on the case where there are mass-points at zero or/and one. More generally, we propose a simple strategy for the estimation of the conditional quantiles of data from mixed distributions, which combines standard results on the estimation of censored and Box-Cox quantile regressions. The implementation of the proposed method is illustrated using a well-known dataset

    Quantiles for counts

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    This paper studies the estimation of conditional quantiles of counts. Given the discreteness of the data, some smoothness has to be artificially imposed on the problem. The methods currently available to estimate quantiles of count data either assume that the counts result from the discretization of a continuous process, or are based on a smoothed objective function. However, these methods have several drawbacks. We show that it is possible to smooth the data in a way that allows inference to be performed using standard quantile regression techniques. The performance and implementation of the estimator are illustrated by simulations and an application.

    Complex Network Tools to Understand the Behavior of Criminality in Urban Areas

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    Complex networks are nowadays employed in several applications. Modeling urban street networks is one of them, and in particular to analyze criminal aspects of a city. Several research groups have focused on such application, but until now, there is a lack of a well-defined methodology for employing complex networks in a whole crime analysis process, i.e. from data preparation to a deep analysis of criminal communities. Furthermore, the "toolset" available for those works is not complete enough, also lacking techniques to maintain up-to-date, complete crime datasets and proper assessment measures. In this sense, we propose a threefold methodology for employing complex networks in the detection of highly criminal areas within a city. Our methodology comprises three tasks: (i) Mapping of Urban Crimes; (ii) Criminal Community Identification; and (iii) Crime Analysis. Moreover, it provides a proper set of assessment measures for analyzing intrinsic criminality of communities, especially when considering different crime types. We show our methodology by applying it to a real crime dataset from the city of San Francisco - CA, USA. The results confirm its effectiveness to identify and analyze high criminality areas within a city. Hence, our contributions provide a basis for further developments on complex networks applied to crime analysis.Comment: 7 pages, 2 figures, 14th International Conference on Information Technology : New Generation

    Relationship of arterial and exhaled CO2 during elevated artificial pneumoperitoneum pressure for introduction of the first trocar.

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    The present study evaluated the correlation between arterial CO2 and exhaled CO2 during brief high-pressure pneumoperitoneum. Patients were randomly distributed into two groups: P12 group (n=30) received a maximum intraperitoneal pressure of 12mmHg, and P20 group (n=37) received a maximum intraperitoneal pressure of 20mmHg. Arterial CO2 was evaluated by radial arterial catheter and exhaled CO2 was measured by capnometry at the following time points: before insufflation, once intraperitoneal pressure reached 12mmHg , 5 minutes after intraperitoneal pressure reached 12mmHg for the P12 group or 20mmHg for the P20 group, and 10 minutes after intraperitoneal pressure reached 12mmHg for the P12 group or when intraperitoneal pressure had decreased from 20mmHg to 12mmHg, for the P20 group. During brief durations of very high intraperitoneal pressure (20mmHg), there was a strong correlation between arterial CO2 and exhaled CO2. Capnometry can be effectively used to monitor patients during transient increases in artificial pneumoperitoneum pressure

    Genetically engineered protein-based polymers with broad antimicrobial activity for biomedical applications

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    With increasing healthcare-associated infections and antibiotic-resistant microorganisms there is a demand not only for new antimicrobial compounds but also for antimicrobial materials. With the use of synthetic protein biotechnology approaches and recombinant DNA technology, we can now create new tailor-made materials with precise control over its sequence. Indeed, by combining antimicrobial activity of naturally occurring antimicrobial peptides (AMPs) with recombinant protein-based polymers, such as elastin-like recombinamers (ELRs), it is possible to create novel materials that can be explored for the development of advanced antimicrobial medical devices. In the present work, we have functionalized an ELR with AMPs for the development of biopolymers with antimicrobial activity. The antimicrobial ELRs were designed by cloning the DNA sequence coding for d

    EHD1 is Required for IGF-1R-mediated Oncogenic Signaling in Ewing Sarcoma

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    Background and Significance: Ewing Sarcoma (EWS) is the second most common malignant bone tumor of children and adolescents. Patients with metastatic or recurrent disease have very poor outcomes. The receptor tyrosine kinase(RTK) insulin-like-growth-factor-1-receptor (IGF-1R) is upregulated in 93% of EWS patients with anti-IGF-1R antibodies and kinase inhibitors in clinical studies. However, with only ~10% of patients achieving objective responses, delineation of novel pathways that facilitate IGF-1R-driven oncogenesis in EWS could provide avenues for more effective therapy. The RTK levels and compartmentalization at the cell surface determine their access to growth factors, thus dictating the downstream oncogenic signaling. Our lab has demonstrated that EPS15-homology-domain-containing-protein-1 (EHD1) regulates traffic of cell surface receptors, including RTKs. We observed high frequency (67%) of EHD1 overexpression in 266 primary EWS patient tumor tissues, and Kaplan-Meier survival analysis of publicly available mRNA expression data showed that high EHD1 expression was associated with shorter patient survival. Objective/Question: This study aims to comprehend the underlying role of EHD1 in EWS oncogenesis. Experimental design and Results: In both dox-inducible EHD1-shRNA knockdown and EHD1-CRISPR-Cas9-knockout (KO) EWS cell line models(TC71, A673, and SKES1), we observed a significant impairment of in vitro oncogenic properties namely, cell proliferation, migration, invasion, soft-agar colony formation, and tumor-sphere formation, and the phenotypes were restored upon mouse-EHD1 rescue. Furthermore, by orthotopically implanting TC71 cells in the tibia of nude mice(xenograft model), we demonstrated a significant reduction in tumor size upon EHD1-depletion. Using a phospho-RTK profiling antibody array, we found reduced phospho-IGF-1R levels upon EHD1-KD, identifying IGF-1R as a potential target of regulation by EHD1. EHD1-KO reduced surface IGF-1R levels under steady-state and ligand-free conditions in EWS cells. IGF-1R and EHD1 were also found to colocalize intracellularly and co-immunoprecipitate after IGF-1 stimulation. Notably, EHD1-KO impaired the IGF-1R-mediated activation of downstream AKT and MAPK pathways. Mechanistically, EHD1 was shown to regulate traffic of newly synthesized IGF-1R and recycled pools from the Golgi to the cell surface, and in absence of EHD1, intracellular IGF-1R was shunted to the lysosome resulting in degradation. Finally, by dual targeting of EHD1 (genetic depletion) and IGF-1R (small-molecule-inhibitor Linsitinib), we observed an additive effect on inhibition of EWS cell proliferation and migration and upregulation of apoptosis. Conclusions: Our studies indicate a novel regulatory pathway of EHD1 requirement in IGF-1R cell surface display and sustaining IGF-1R-mediated oncogenesis in EWS. This highlights the prospects of therapeutic co-targeting of EHD1 and IGF-1R, thus enhancing IGF-1R targeted therapies in EWS.https://digitalcommons.unmc.edu/chri_forum/1040/thumbnail.jp

    Multicompartment body composition analysis in older adults: a cross-sectional study

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    Background During aging, changes occur in the proportions of muscle, fat, and bone. Body composition (BC) alterations have a great impact on health, quality of life, and functional capacity. Several equations to predict BC using anthropometric measurements have been developed from a bi-compartmental (2-C) approach that determines only fat mass (FM) and fat-free mass (FFM). However, these models have several limitations, when considering constant density, progressive bone demineralization, and changes in the hydration of the FFM, as typical changes during senescence. Thus, the main purpose of this study was to propose and validate a new multi-compartmental anthropometric model to predict fat, bone, and musculature components in older adults of both sexes. Methods This cross-sectional study included 100 older adults of both sexes. To determine the dependent variables (fat mass [FM], bone mineral content [BMC], and appendicular lean soft tissue [ALST]) whole total and regional dual-energy X-ray absorptiometry (DXA) body scans were performed. Twenty-nine anthropometric measures and sex were appointed as independent variables. Models were developed through multivariate linear regression. Finally, the predicted residual error sum of squares (PRESS) statistic was used to measure the effectiveness of the predicted value for each dependent variable. Results An equation was developed to simultaneously predict FM, BMC, and ALST from only four variables: weight, half-arm span (HAS), triceps skinfold (TriSK), and sex. This model showed high coefficients of determination and low estimation errors (FM: R2adj: 0.83 and SEE: 3.16; BMC: R2adj: 0.61 and SEE: 0.30; ALST: R2adj: 0.85 and SEE: 1.65). Conclusion The equations provide a reliable, practical, and low-cost instrument to monitor changes in body components during the aging process. The internal cross-validation method PRESS presented sufficient reliability in the model as an inexpensive alternative for clinical field use.info:eu-repo/semantics/publishedVersio
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