Total positivity: tests and parametrizations

An introduction to total positivity (TP), with the emphasis on efficient TP criteria and parametrizations of TP matrices. Intended for general mathematical audience.Comment: 20 pages, with color figure

Inclusion of higher order terms for small-signal (modal) analysis: Committee report - task force on assessing the need to include higher order terms for small-signal (modal) analysis

© 2005 IEEE.This paper summarizes the work done by the Task Force on Assessing the Need to Include Higher Order Terms for Small-Signal (Modal) Analysis. This Task Force was created by the Power System Dynamic Performance Committee to investigate the need to include higher order terms for small signal (modal) analysis. The focus of the work reported here is on establishing and documenting the practical significance of these terms in stability analysis using the method of Normal Forms. Special emphasis was placed on determining and describing conditions when higher order terms need to be included to accurately describe modal interactions. Test cases were developed on a standard test system to demonstrate the application of appropriate indices to detect the occurrence of nonlinear interaction and hence the need for higher order terms in stability analyzes. The use of the higher order terms in the site selection for a damping controller is also documented.Sanchez-Gasca, Juan J.,Vittal, Vijay; Gibbard, Michael J.; Messina, Arturo Roman; Vowles, David J.; Liu, Shu; Annakkage, Udaya D

Regulation of mammary gland branching morphogenesis by the extracellular matrix and its remodeling enzymes.

A considerable body of research indicates that mammary gland branching morphogenesis is dependent, in part, on the extracellular matrix (ECM), ECM-receptors, such as integrins and other ECM receptors, and ECM-degrading enzymes, including matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). There is some evidence that these ECM cues affect one or more of the following processes: cell survival, polarity, proliferation, differentiation, adhesion, and migration. Both three-dimensional culture models and genetic manipulations of the mouse mammary gland have been used to study the signaling pathways that affect these processes. However, the precise mechanisms of ECM-directed mammary morphogenesis are not well understood. Mammary morphogenesis involves epithelial 'invasion' of adipose tissue, a process akin to invasion by breast cancer cells, although the former is a highly regulated developmental process. How these morphogenic pathways are integrated in the normal gland and how they become dysregulated and subverted in the progression of breast cancer also remain largely unanswered questions

Biotechnological production and application of fructooligosaccharides

Currently, prebiotics are all carbohydrates of relatively short chain length. An important group is the fructooligosaccharides, which are a special kind of prebiotics associated to their selective stimulation of the activity of certain groups of colonic bacteria that have a positive and beneficial effect on intestinal microbiota, reducing incidence of gastrointestinal infections, respiratory and also possessing a recognized bifidogenic effect. Traditionally, these prebiotic compounds have been obtained through extraction processes from some plants, as well as through enzymatic hydrolysis of sucrose. However, different fermentative methods have also been proposed for the production of fructooligosaccharides, such as solid-state fermentation utilizing various agroindustrial by-products. By optimizing the culture parameters, fructooligosaccharides yields and productivity can be improved. The use of immobilized enzymes and cells has also been proposed as being an effective and economic method for large-scale production of fructooligosaccharides. This paper is an overview on the results of recent studies on fructooligosacharides biosynthesis, physicochemical properties, sources, biotechnological production and applications.The authors thank the National Council of Science and Technology of Mexico (CONACYT) for funding this study. D. A. Flores-Maltos thank the CONACYT for the financial support provided for her postgraduate studies in the Food Science and Technology Program, Universidad Autonoma de Coahuila, Mexico

Harmonizing methods for wildlife abundance estimation and pathogen detection in Europe-a questionnaire survey on three selected host-pathogen combinations

__Background:__ The need for wildlife health surveillance as part of disease control in wildlife, domestic animals and humans on the global level is widely recognized. However, the objectives, methods and intensity of existing wildlife health surveillance programs vary greatly among European countries, resulting in a patchwork of data that are difficult to merge and compare. This survey aimed at evaluating the need and potential for data harmonization in wildlife health in Europe. The specific objective was to collect information on methods currently used to estimate host abundance and pathogen prevalence. Questionnaires were designed t

Polynomial Heuristic Algorithms for Inconsistency Characterization in Firewall Rule Sets

Firewalls provide the first line of defence of nearly all networked institutions today. However, Firewall ACLs could have inconsistencies, allowing traffic that should be denied or vice versa. In this paper, we analyze the inconsistency characterization problem as a separate problem of the diagnosis one, and propose formal definitions in order to characterize one-to-many inconsistencies. We identify the combinatorial part of the problem that generates exponential complexities in combined diagnosis and characterization algorithms proposed by other authors. Then we propose a decomposition of the combinatorial problem in several smaller combinatorial ones, which can effectively reduce the complexity of the problem. Finally, we propose an approximate heuristic and algorithms to solve the problem in worst case polynomial time. Although many algorithms have been proposed to address this problem, all of them are combinatorial. The presented algorithms are an heuristic way to solve the problem with polynomial complexity. There are no constraints on how rule field ranges are expressed

Short-term exposure to carbamazepine causes oxidative stress on common carp (Cyprinus carpio)

Artículo científico en revista indizadaThe aim of this research was to determine the bioconcentration factor and if subacute exposure to carbama- zepine (2 mg L−1) modifies the oxidative state of liver, gills and brain of Cyprinus carpio. This was measured through the following biomarkers: hydroperoxide and protein carbonyl content, lipid peroxidation degree, as well as superoxide dismutase, catalase and glutathione peroxidase activity. Carbamazepine concentration in carp’s tissue was also determined by liquid chromatography with a diode arrangement detector. An increase in lipid peroxidation degree, hydroperoxide and protein carbonyl content, and a decrease in the activity of the antioxidant enzymes (P < 0.05) with respect to control was observed. Also, there is an increase in the con- centration of carbamazepina present in the organs with respect to the water in the system, which denotes bioconcentration of the drug. In conclusion, carbamazepine is bioconcentrated and produces oxidative stress on the common carp (C. carpio).Secretaría de Investigación y Posgrado del Instituto Politécnico Nacional (SIP-IPN 20170919)

A multicentre randomised phase III trial comparing pembrolizumab versus single-agent chemotherapy for advanced pre-treated malignant pleural mesothelioma: the European Thoracic Oncology Platform (ETOP 9-15) PROMISE-meso trial.

Malignant pleural mesothelioma (MPM) is an aggressive malignancy characterised by limited treatment options and a poor prognosis. At relapse after platinum-based chemotherapy, single-agent chemotherapy is commonly used and single-arm trials of immune-checkpoint inhibitors have demonstrated encouraging activity. PROMISE-meso is an open-label 1:1 randomised phase III trial investigating the efficacy of pembrolizumab (200 mg/Q3W) versus institutional choice single-agent chemotherapy (gemcitabine or vinorelbine) in relapsed MPM patients with progression after/on previous platinum-based chemotherapy. Patients were performance status 0-1 and unselected for programmed cell death ligand 1 (PD-L1) status. At progression, patients randomly assigned to receive chemotherapy were allowed to crossover to pembrolizumab. The primary end point was progression-free survival (PFS), assessed by blinded independent central review (BICR). Secondary end points were overall survival (OS), investigator-assessed PFS, objective response rate (ORR), and safety. Efficacy by PD-L1 status was investigated in exploratory analyses. Between September 2017 and August 2018, 144 patients were randomly allocated (pembrolizumab: 73; chemotherapy: 71). At data cut-off [20 February 2019, median follow-up of 11.8 months (interquartile range: 9.9-14.5)], 118 BICR-PFS events were observed. No difference in BICR-PFS was detected [hazard ratio = 1.06, 95% confidence interval (CI): 0.73-1.53; P = 0.76], and median BICR-PFS (95% CI) for pembrolizumab was 2.5 (2.1-4.2), compared with 3.4 (2.2-4.3) months for chemotherapy. A difference in ORR for pembrolizumab was identified (22%, 95% CI: 13% to 33%), over chemotherapy (6%, 95% CI: 2% to 14%; P = 0.004). Forty-five patients (63%) assigned to chemotherapy received pembrolizumab at progression. With follow-up to 21 August 2019 [17.5 months: (14.8-19.7)], no difference in OS was detected between groups (HR = 1.12, 95% CI: 0.74-1.69; P = 0.59), even after adjusting for crossover. Pembrolizumab safety was consistent with previous observations. Exploratory efficacy analyses by PD-L1 status demonstrated no improvements in ORR/PFS/OS. This is the first randomised trial evaluating the efficacy of pembrolizumab in MPM patients progressing after/on previous platinum-based chemotherapy. In biologically unselected patients, although associated with an improved ORR, pembrolizumab improves neither PFS nor OS over single-agent chemotherapy