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The aim of this article is to propose a critical reflection of the state of teaching sustainability in higher education in Chile. The goal is to broaden the concept of sustainability so as to understand its implication in learning civic and community values, as well as in implementing innovative teaching methodologies linked to the promotion of sustainable values connected to the United Nations’ Sustainable Development Goals. In this article, the application of a teaching methodology called Pre-Texts, from Harvard University, is explored in a sociocultural context of Chilean higher education, specifically at the Universidad de La Frontera in Chile’s 9th Region. Evidence is sought about how this methodology is relevant and effective in the teaching of two key pedagogical principles related to sustainability: the importance of community recognition and the collective work and implementation of artistic practices to promote discussion of sustainable principles based on preservation and recycling. Finally, a conclusion will be pursued around the need to implement these and similar teaching practices in higher education to promote greater awareness of the fundamental principles of Sustainable Development.

The Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory has detected more than 20 Active Galactic Nuclei (AGN) at photon energies above 30 MeV.

We present techniques that mine fully sequenced microbial genomes for functional relationships between genes. We show that genes related by one of four techniques are more likely to belong to the same cellular pathways. Furthermore, we demonstrate that the pathway of an uncharacterized gene may be inferred from those of its functionally related partners. Therefore, we are now able to assign most of the genes within bacteria to cellular pathways.

Using the first three and a half years of observations from the Energetic Gamma Ray Telescope (EGRET) on board the Compton Gamma Ray Observatory (CGRO), phase-resolved analyses are performed on the emission from the three brightest high-energy gamma-ray pulsars, Crab, Geminga, and Vela. For each pulsar, it is found that there is detectable high-energy gamma-ray emission above the galactic diffuse background throughout much of the pulsar rotation cycle. A hardness ratio is introduced to characterize the evolution of the spectral index as a function of pulsar phase. While the hardest emission from the Crab and Vela pulsars comes from the bridge region between the two gamma-ray peaks, the hardest emission from Geminga corresponds to the second gamma-ray peak. For all three pulsars, phase-resolved spectra of the pulse profile components reveal that although there is a large variation in the spectral index over the pulsar phase interval, the high-energy spectral turnover, if any, occurs at roughly the same energy in each component. The high-energy gamma-ray emission from the Crab complex appears to include an unpulsed ultra-soft component of spectral index ~ -4.3 which dominates the total emission below 100 MeV. This component is consistent with the expected emission from the tail end of the Crab nebula synchrotron emission., Comment: 20 pages, 11 figures, 7 tables. Accepted for publication in the Astrophysical Journal

The EGRET instrument aboard the Compton Gamma Ray Observatory (CGRO) has completed the first all-sky survey in high-energy gamma rays and has repeatedly viewed selected portions of the sky. Analysis of the region with galactic latitude $+10\arcdeg < b < +40\arcdeg$ indicates the presence of nineteen point sources, including nine which can be identified as active galactic nuclei, some of which have been reported previously, as well as ten other sources with no definite counterparts. Using the combined exposures from Phase 1 and Phase 2 of the CGRO viewing program, the spectra, time variability, and positions of all detected sources in this region are determined. It is tentatively suggested that one of the unidentified sources might be associated with the radio galaxy Centaurus A., Comment: 18 pages, 3 Postscript figures (one of 3 pages) Uses aaspp4.sty

We detected a sixth high-energy gamma-ray pulsar, PSR B1951+32, pulsating in gamma rays at E ≥ 100 MeV with the same 39.5 ms periodicity as in radio, using the data obtained during 1991 May to 1994 July by the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma Ray Observatory. Although seen only as a weak source amidst the high background of galactic disk emission, the pulsation in high-energy gamma rays is clearly seen. The pulsed radiation has a photon spectral index of -1.74 ± 0.11. There is no evidence as yet for unpulsed emission from the object. The pulsar appears to have an efficiency of ~0.004 for converting its rotational energy loss into gamma rays at E ≥ 100 MeV.

The EGRET instrument on the Compton Gamma Ray Observatory, which detects photons in the energy range 30 MeV to 30 GeV, has detected about 40 sources of gamma rays (>100 MeV) at high galactic latitudes. Most of these appear to be associated with bright, flat-spectrum radio sources, many of which have been previously classified as optically violent variable (OVV) quasars or BL Lac objects (together often referred to as blazars). The remaining sources are presently unidentified, although some of them are positionally compatible with flat-spectrum radio sources which are somewhat less bright and less well-studied.

This paper provides a summary of the data reduction and analysis procedures used by the Energetic Gamma Ray Experimental Telescope (EGRET) team. The steps are summarized beginning with the extensive calibration, proceeding to the basic data reduction, and finishing with the data analysis techniques, including a brief description of the source determination, the intensity calculation, the spectral evaluation, the pulsar program, and time variations. References are provided for the detailed discussions of the major portions of the work. The types of data and the software available to Guest Investigators are also reviewed with guides to more detailed descriptions. In this way, the overview is given in one place with references for those wishing to see parts in detail.

The Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Observatory has detected, with a high degree of certainty, more than 20 active galactic nuclei (AGN) in high energy gamma‐ray (E≳100 MeV). All of these sources appear to be members of the blazar class of AGN, exhibiting one or more of the characteristics of this source class (flat radio spectrum, strong variability, optical polarization).Variability on time scales from days to months or longer is a characteristic of the gamma‐ray emission from most of the blazars detected by EGRET. In this paper the EGRET observations of variability are summarized and some of the implications for emission models are discussed. In particular, the EGRET observations and consideration of gamma‐ray absorption via photon‐photon pair production strongly suggest that the gamma radiation from AGN is beamed toward us. This is consistent with the interpretation of blazars as objects in which the non‐thermal radiation arises predominantly from a ‘‘jet’’ of relativis...

The EGRET instrument aboard the Compton Gamma‐Ray Observatory has detected gamma‐ray emission from many Active Galactic Nuclei during the Phase I & II observation periods. With the continuing discovery of gamma‐ray loud AGN, it becomes increasingly important to characterize the luminosity and density distribution of these objects in order to understand how the gamma‐ray characteristics are related to properties observed at radio, optical and X‐ray wavelengths. The 〈V/Vmax〉 test is applied to the population of gamma‐ray loud Active Galactic Nuclei which have been observed by the EGRET instrument during the Phase I all‐sky survey. Evidence for luminosity evolution is presented, and estimates of the degree of evolution are made given standard assumptions about the cosmology and the form of the luminosity evolution. The effects of observational biases due to gamma‐ray flux‐detection limits and optical identifications are considered.

The EGRET phase 1 & 2 observations of Geminga have been used to determine an optimum contemporary ephemeris using the ‘‘Z2n timing method.’’ The residuals for this linear ephemeris over 2.1 years are less than 5 ms, suggesting that Geminga has not glitched. A position estimate is found to be consistent with the G‘ optical counterpart. The comparison of f between this ephemeris and that of COS‐B yields an estimate of f which is an order of magnitude smaller than that determined from the COS‐B data. It is estimated that the anticipated EGRET phase 3 Geminga exposure will allow for the comparison of Geminga phase between EGRET, COS‐B, and SAS‐2.

The EGRET gamma‐ray telescope has detected a persistent source of high energy gamma rays which has not been identified. It was detected in seven different observations in 1991–1993. Variations in the spectrum, combined with a galactic latitude of +25°, make it likely that this is a previously unknown blazar.

The Compton Observatory was pointed at Cygnus twice during the full sky survey (5/30–6/8/91 & 8/8–8/15/91). The COS‐B sources 2CG 075+00 and 2CG 078+01 are detected by EGRET, and smaller error boxes have been obtained, but the sources are not yet identified at other wavelengths. An excess of counts is noted at the position of Cygnus X‐3 consistent with a point source. The corresponding flux is 8±2×10−7 cm−2 s−1 (E≳0.1 GeV)—a factor of 5 less than the flux reported by the SAS‐2 group for Cygnus X‐3. The observed intensities for the individual periods were consistent with no change in intensity between the first and second observations (the second observation began two weeks after the beginning of the July 1991 radio flare). More work is required to refine and verify the galactic diffuse model (which comprises at least 10 times more flux than Cygnus X‐3 in this direction) before a definitive Cygnus X‐ray point‐source result will be obtained. The 4.8 hr X‐ray periodicity of Cygnus X‐3 is not detected in exta...

Ever since the detection of the Crab and Vela pulsars as high‐energy gamma‐ray sources, there has been speculation that many pulsars might be gamma‐ray emitters, some of which might be detectable with more sensitive instruments. Based on theoretical considerations, most interest has focused on young pulsars where a relatively high fraction of the spin down energy might be expected to be carried away in gamma rays. Millisecond pulsars have also been suggested as possible detectable gamma‐ray sources. Consequently, the Compton Gamma Ray Observatory was designed with the ability to time tag gamma rays to an accuracy of a tenth of a millisecond in absolute time. This is needed in view of the long integration times required because of the low expected fluxes. In addition, a cooperative effort has been organized with radio astronomers who are making contemporary measurements of the ephemerides of a relatively large fraction of known pulsars which might be expected to be candidate gamma‐ray ‘‘pulsars’’ based on ...

Nature 437, 376–380 (2005) In this paper, the second name of Chun Heen Ho was misspelled as He. In the earlier Corrigendum (Nature 439, 502; 2006) the surnames of Stephen K. Hutchison and Brian C. Godwin were misspelled as Hutchinson and Goodwin. In addition, in the Supplementary Information of the original paper, there were errors in the sequences of the DNA capture and enrichment primers, and in the formulation of emulsion oil.

The advent of whole-genome sequencing has led to methods that infer protein function and linkages. We have combined four such algorithms (phylogenetic profile, Rosetta Stone, gene neighbor and gene cluster) in a single database - Prolinks - that spans 83 organisms and includes 10 million high-confidence links. The Proteome Navigator tool allows users to browse predicted linkage networks interactively, providing accompanying annotation from public databases. The Prolinks database and the Proteome Navigator tool are available for use online at http://dip.doe-mbi.ucla.edu/pronav.

Gamma radiation above 100 MeV in energy has been detected from the radio pulsar PSR1706-44. The gamma emission forms a single broad peak within the pulsar period of 102 ms, in contrast to the two narrow peaks seen in the other three known high-energy gamma-ray pulsars. The emission mechanism in all cases is probably the same, the differences arising from the geometry of the magnetic and rotation axes and the line of sight. Gamma-ray emission accounts for as much as 1 percent of the total neutron star spindown energy in these pulsars, much more than emerges at optical or radio frequencies. Thus, study of this emission is important in understanding pulsar emission and evolution.

As part of its ongoing survey of the high-energy gamma-ray sky, the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory has searched for emission from spin-powered pulsars, five of which have now been detected in the energy range 30 MeV less than or = E less than or = 20 GeV. A systematic study of the all-sky survey has found no additional pulsed gamma-ray sources. The pulsar detections, coupled with the upper limits on pulsed gamma radiation from other radio pulsars, indicate that the simplest models of gamma-ray pulsars are incomplete.

The Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) has carried out extensive studies of the gamma-ray source Geminga. Following the detection of pulsed X-rays (Halpern and Holt 1992) from Geminga, Bertsch et al. (1992) reported the same 237 ms periodicity to be visible in the EGRET data. A full analysis of the Geminga source shows that the energy spectrum is compatible with a power law with a spectral index of -1.50 +/- 0.08 between 30 MeV and 2 GeV. A falloff relative to the power law is observed for energies above 2 GeV. Phase-resolved spectra also show power laws with high-energy cutoffs, but with significant variation of the spectral index with phase. No unpulsed emission is observed. No evidence for time variation was found within the EGRET observations.

Nature 359, 615-616 (1992)IN Fig. 2 of this letter, the y-'dxis should be labelled as Photons (cm2 s MeV) ' and not Photons (cm2 s GeV) ' as published.

The Crab pulsar and nebula were observed three times in 1991 April to June by the Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory (CGRO): April 23 to May 7, May 16 to 30, and June 8 to 15. The results of analysis of the gamma-ray emission in the energy range from 50 MeV to more than 10 GeV are reported. The observed gamma-ray light curve exhibits two peaks separated in phase by 0.40 +/- 0.02, consistent with previous observations. The total pulsed emission from the Crab pulsar is found to be well represented by a power-law spectrum, softer than the spectrum measured by COS B (Clear et al., 1987). The interpulse emission has a harder spectrum than either of the pulses. The evidence for pulsed emission above 5 GeV in the EGRET data is not conclusive. Unpulsed emission in the energy range 50 MeV to 5 GeV was detected, with an indication of a hardening of the unpulsed spectrum above about 1 GeV. There was a significant change in the light curve over the 2 months of these observations, although the shape of the spectrum remained constant.

We report upper limits to the high-energy gamma-ray emission from the millisecond pulsars (MSPs) in a number of globular clusters. The observations were done as part of an all-sky survey by the energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) during Phase I of the CGRO mission (1991 June to 1992 November). Several theoretical models suggest that MSPs may be sources of high-energy gamma radiation emitted either as primary radiation from the pulsar magnetosphere or as secondary radiation generated by conversion into photons of a substantial part of the relativistic e(+/-) pair wind expected to flow from the pulsar. To date, no high-energy emission has been detected from an individual MSP. However, a large number of MSPs are expected in globular cluster cores where the formation rate of accreting binary systems is high. Model predictions of the total number of pulsars range in the hundreds for some clusters. These expectations have been reinforced by recent discoveries of a substantial number of radio MSPs in several clusters; for example, 11 have been found in 47 Tucanae (Manchester et al.). The EGRET observations have been used to obtain upper limits for the efficiency eta of conversion of MSP spin-down power into hard gamma rays. The upper limits are also compared with the gamma-ray fluxes predicted from theoretical models of pulsar wind emission (Tavani). The EGRET limits put significant constraints on either the emission models or the number of pulsars in the globular clusters.