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.

Fermi Observations of GRB 090902B: A Distinct Spectral Component in the Prompt and Delayed Emission

Abstract: We report on the observation of the bright, long gamma-ray burst (GRB), GRB 090902B, by the Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) instruments on-board the Fermi observatory. ...

Environmental strategies and green product development: an overview on sustainability‐driven companies

Abstract: To respond effectively and efficiently to the environmental sustainability challenge, an important role can be played by companies, through appropriate strategies and operations, such as green processes and product development. In this paper, we investigate whether the development of green products is supported by the environmental strategic approaches adopted by sustainability-driven companies, and whether there are economic sector or geographical area specificities. To this purpose, first we develop a taxonomy of environmental strategies and we define measurable proxies for both the environmental strategic approaches identified and the green product development. Then, we study a sample represented by the companies included in the Dow Jones Sustainability World Index (DJSWI). The methodology used is based on the content analysis of companies' websites and relevant documents, such as environmental and sustainability reports. The main result is that the levels of adoption of different environmental strategic approaches are higher for green product developers than for green product non-developers. Moreover, the most implemented strategic approaches for green product developers vary depending on the economic sector, while a more homogeneous behaviour is found from the geographical perspective. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.

FLOWERING LOCUS T Protein May Act as the Long-Distance Florigenic Signal in the Cucurbits

Abstract: Cucurbita moschata, a cucurbit species responsive to inductive short-day (SD) photoperiods, and Zucchini yellow mosaic virus (ZYMV) were used to test whether long-distance movement of FLOWERING LOCUS T (FT) mRNA or FT is required for floral induction. Ectopic expression of FT by ZYMV was highly effective in mediating floral induction of long-day (LD)–treated plants. Moreover, the infection zone of ZYMV was far removed from floral meristems, suggesting that FT transcripts do not function as the florigenic signal in this system. Heterografting demonstrated efficient transmission of a florigenic signal from flowering Cucurbita maxima stocks to LD-grown C. moschata scions. Real-time RT-PCR performed on phloem sap collected from C. maxima stocks detected no FT transcripts, whereas mass spectrometry of phloem sap proteins revealed the presence of Cm-FTL1 and Cm-FTL2. Importantly, studies on LD- and SD-treated C. moschata plants established that Cmo-FTL1 and Cmo-FTL2 are regulated by photoperiod at the level of movement into the phloem and not by transcription. Finally, mass spectrometry of florally induced heterografted C. moschata scions revealed that C. maxima FT, but not FT mRNA, crossed the graft union in the phloem translocation stream. Collectively, these studies are consistent with FT functioning as a component of the florigenic signaling system in the cucurbits.