Instituto Politécnico Nacional

About: Instituto Politécnico Nacional is a education organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Population & Context (language use). The organization has 43351 authors who have published 63315 publications receiving 938532 citations. The organization is also known as: Instituto Politécnico Nacional & Instituto Politecnico Nacional.

Stereospezifische Katalysen und isotaktische Polymere

Abstract: Bei der Stereoisomerie von Hochpolymeren aus Vinyl-Monomeren sind ataktische, isotaktische und syndyotaktische Strukturen zu unterscheiden. Die Bildungsvoraussetzungen dieser Formen, die Arten der Reaktionsablaufe sowie die Eigenschaften der erhaltenen Produkte werden in Einzelheiten dargelegt. Es zeigt sich, das ein anionischer Polymerisationsablauf das Entstehen von Polymeren regelmasiger Struktur begunstigt. Die hierfur brauchbaren Katalysatoren werden beschrieben.

Global spatial risk assessment of sharks under the footprint of fisheries

Abstract: Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.

Observation of the Crab Nebula with the HAWC Gamma-Ray Observatory

Abstract: Author(s): Abeysekara, AU; Albert, A; Alfaro, R; Alvarez, C; Alvarez, JD; Arceo, R; Arteaga-Velazquez, JC; Solares, HAA; Barber, AS; Bautista-Elivar, N; Becerril, A; Belmont-Moreno, E; Benzvi, SY; Berley, D; Braun, J; Brisbois, C; Caballero-Mora, KS; Capistran, T; Carraminana, A; Casanova, S; Castillo, M; Cotti, U; Cotzomi, J; Leon, SCD; Fuente, EDL; Leon, CD; Deyoung, T; Dingus, BL; Duvernois, MA; Diaz-Velez, JC; Ellsworth, RW; Fiorino, DW; Fraija, N; Garcia-Gonzalez, JA; Gerhardt, M; Munoz, AG; Gonzalez, MM; Goodman, JA; Hampel-Arias, Z; Harding, JP; Hernandez, S; Hernandez-Almada, A; Hinton, J; Hui, CM; Huntemeyer, P; Iriarte, A; Jardin-Blicq, A; Joshi, V; Kaufmann, S; Kieda, D; Lara, A; Lauer, RJ; Lee, WH; Lennarz, D; Vargas, HL; Linnemann, JT; Longinotti, AL; Raya, GL; Luna-Garcia, R; Lopez-Coto, R; Malone, K; Marinelli, SS; Martinez, O; Martinez-Castellanos, I; Martinez-Castro, J; Martinez-Huerta, H; Matthews, JA; Miranda-Romagnoli, P; Moreno, E; Mostafa, M; Nellen, L; Newbold, M; Nisa, MU; Noriega-Papaqui, R; Pelayo, R; Pretz, J; Perez-Perez, EG; Ren, Z; Rho, CD; Riviere, C; Rosa-Gonzalez, D; Rosenberg, M; Ruiz-Velasco, E; Salazar, H; Greus, FS | Abstract: The Crab Nebula is the brightest TeV gamma-ray source in the sky and has been used for the past 25 years as a reference source in TeV astronomy, for calibration and verification of new TeV instruments. The High Altitude Water Cherenkov Observatory (HAWC), completed in early 2015, has been used to observe the Crab Nebula at high significance across nearly the full spectrum of energies to which HAWC is sensitive. HAWC is unique for its wide field of view, nearly 2 sr at any instant, and its high-energy reach, up to 100 TeV. HAWC's sensitivity improves with the gamma-ray energy. Above ∼1 TeV the sensitivity is driven by the best background rejection and angular resolution ever achieved for a wide-field ground array. We present a time-integrated analysis of the Crab using 507 live days of HAWC data from 2014 November to 2016 June. The spectrum of the Crab is fit to a function of the form φ(E)= φ0(E/E0)-α-β In(E/E0). The data is well fitted with values of α = 2.63 ±0.03, β = 0.15 ±0.03, and log10(φ0cm2s TeV)=-12.60±0.02 when E 0 is fixed at 7 TeV and the fit applies between 1 and 37 TeV. Study of the systematic errors in this HAWC measurement is discussed and estimated to be ±50% in the photon flux between 1 and 37 TeV. Confirmation of the Crab flux serves to establish the HAWC instrument's sensitivity for surveys of the sky. The HAWC all-sky survey will be the deepest survey of the northern sky ever conducted in the multi-TeV band.

Small projects/large changes: Participatory design as an open participated process

Abstract: This paper examines the need for large-scale, sustainable changes, and the effects of citizens' active participation and design co-operating to realise such changes. Section 1, starting from Pelle Ehn's last contribution, deals with participatory design and how it can be extended from the traditional idea of participation as the integration of users in projects, to the concept of participation as the interaction of active groups of citizens with open and articulated processes in the direction of socio-technical changes. Section 2 introduces the idea of planning by projects strategy and presents five design projects. Section 3 discusses how participatory design can be extended to give a rationale for these large-scale projects and what designers did in practice: triggered citizens’ interest, aligned their motivations and empowered their capabilities. The idea emerging from this discussion is that when participatory design is intended as an approach aiming at broad and complex transformation processes its t...

Using Resistin, glucose, age and BMI to predict the presence of breast cancer

Abstract: The goal of this exploratory study was to develop and assess a prediction model which can potentially be used as a biomarker of breast cancer, based on anthropometric data and parameters which can be gathered in routine blood analysis. For each of the 166 participants several clinical features were observed or measured, including age, BMI, Glucose, Insulin, HOMA, Leptin, Adiponectin, Resistin and MCP-1. Machine learning algorithms (logistic regression, random forests, support vector machines) were implemented taking in as predictors different numbers of variables. The resulting models were assessed with a Monte Carlo Cross-Validation approach to determine 95% confidence intervals for the sensitivity, specificity and AUC of the models. Support vector machines models using Glucose, Resistin, Age and BMI as predictors allowed predicting the presence of breast cancer in women with sensitivity ranging between 82 and 88% and specificity ranging between 85 and 90%. The 95% confidence interval for the AUC was [0.87, 0.91]. These findings provide promising evidence that models combining age, BMI and metabolic parameters may be a powerful tool for a cheap and effective biomarker of breast cancer.