One place doesn't fit all: improving the effectiveness of sustainability standards by accounting for place

Includes bibliographical references (pages 8-10).The growing interest in incentivizing sustainable agricultural practices is supported by a large network of voluntary production standards, which aim to offer farmers and ranchers increased value for their product in support of reduced environmental impact. To be effective with producers and consumers alike, these standards must be both credible and broadly recognizable, and thus are typically highly generalizable. However, the environmental impact of agriculture is strongly place-based and varies considerably due to complex biophysical, socio-cultural, and management-based factors, even within a given sector in a particular region. We suggest that this contradiction between the placeless generality of standards and the placed-ness of agriculture renders many sustainability standards ineffective. In this policy and practice review, we examine this contradiction through the lens of beef production, with a focus on an ongoing regional food purchasing effort in Denver, Colorado, USA. We review the idea of place in the context of agricultural sustainability, drawing on life cycle analysis and diverse literature to find that recognition of place-specific circumstances is essential to understanding environmental impact and improving outcomes. We then examine the case of the Good Food Purchasing Program (GFPP), a broad set of food-purchasing standards currently being implemented for institutional purchasing in Denver. The GFPP was created through a lengthy stakeholder-inclusive process for use in Los Angeles, California, USA, and has since been applied to many cities across the country. The difference between Los Angeles' process and that of applying the result of Los Angeles' process to Denver is instructive, and emblematic of the flaws of generalizable sustainability standards themselves. We then describe the essential elements of a place-based approach to agricultural sustainability standards, pointing toward a democratic, process-based, and outcome-oriented strategy that results in standards that enable rather than hinder the creativity of both producers and consumers. Though prescription is anathema to our approach, we close by offering a starting point for the development of standards for beef production in Colorado that respect the work of people in place

Structural network heterogeneities and network dynamics: a possible dynamical mechanism for hippocampal memory reactivation

The hippocampus has the capacity for reactivating recently acquired memories [1-3] and it is hypothesized that one of the functions of sleep reactivation is the facilitation of consolidation of novel memory traces [4-11]. The dynamic and network processes underlying such a reactivation remain, however, unknown. We show that such a reactivation characterized by local, self-sustained activity of a network region may be an inherent property of the recurrent excitatory-inhibitory network with a heterogeneous structure. The entry into the reactivation phase is mediated through a physiologically feasible regulation of global excitability and external input sources, while the reactivated component of the network is formed through induced network heterogeneities during learning. We show that structural changes needed for robust reactivation of a given network region are well within known physiological parameters [12,13].Comment: 16 pages, 5 figure

Discovery of a Luminous Quasar in the Nearby Universe

In the course of the Pico dos Dias survey (PDS), we identified the stellar like object PDS456 at coordinates alpha = 17h 28m 19.796s, delta = -14deg 15' 55.87'' (epoch 2000), with a relatively nearby (z = 0.184) and bright (B = 14.69) quasar. Its position at Galactic coordinates l_II = 10.4deg, b_II = +11.2deg, near the bulge of the Galaxy, may explain why it was not detected before. The optical spectrum of PDS456 is typical of a luminous quasar, showing a broad (FWHM ~ 4000 km/s) H_\beta line, very intense FeII lines and a weak [OIII]\lambda5007 line. PDS456 is associated to the infrared source IRAS 17254-1413 with a 60 \mum infrared luminosity L_{60} = 3.8 x 10^{45} erg/s. The relatively flat slopes in the infrared (\alpha(25,60) = -0.33 and \alpha(12,25) = -0.78) and a flat power index in the optical (F_{\nu} \propto \nu^{-0.72}) may indicate a low dust content. A good match between the position of PDS456 and the position of the X-ray source RXS J172819.3-141600 implies an X-ray luminosity L_x = 2.8 x 10^{44} erg/s. The good correlation between the strength of the emission lines in the optical and the X-ray luminosity, as well as the steep optical to X-ray index estimated (\alpha_{ox} = -1.64) suggest that PDS456 is radio quiet. A radio survey previously performed in this region yields an upper limit for radio power at ~ 5 GHz of ~ 2.6 x 10^{30} erg/s/Hz. We estimate the Galactic reddening in this line-of-sight to be A_B \simeq 2.0, implying an absolute magnitude M_B = -26.7 (using H_0 = 75 km s^{-1} Mpc^{-1} and q_0 = 0). In the optical, PDS456 is therefore 1.3 times more luminous than 3C 273 and the most luminous quasar in the nearby (z \leq 0.3) Universe.Comment: 12 pages, LaTeX (aasms4.sty) + 3 figures; accepted for publication in the Astrophysical Journal Letter

Discovery of optical pulsations in V2116 Ophiuchi/GX 1+4

We report the detection of pulsations with $\sim 124$ s period in V2116 Oph, the optical counterpart of the low-mass X-ray binary GX 1+4. The pulsations are sinusoidal with modulation amplitude of up to 4% in blue light and were observed in ten different observing sessions during 1996 April-August using a CCD photometer at the 1.6-m and 0.6-m telescopes of Laborat\'orio Nacional de Astrof\'{\i}sica, in Brazil. The pulsations were also observed with the $UBVRI$ fast photometer. With only one exception the observed optical periods are consistent with those observed by the BATSE instrument on board the Compton Gamma Ray Observatory at the same epoch. There is a definite correlation between the observability of pulsations and the optical brightness of the system: V2116~Oph had $R$ magnitude in the range $15.3-15.5$ when the pulsed signal was detected, and $R = 16.0-17.7$ when no pulsations were present. The discovery makes GX 1+4 only the third of $\sim 35$ accretion-powered X-ray pulsars to be firmly detected as a pulsating source in the optical. The presence of flickering and pulsations in V2116 Oph adds strong evidence for an accretion disk scenario in this system. The absolute magnitude of the pulsed component on 1996 May 27 is estimated to be $M_V \sim -1.5$. The implied dimensions for the emitting region are 1.1 R_{\sun}, 3.2 R_{\sun}, and 7.0 R_{\sun}, for black-body spectral distributions with $T = 10^5$ K, $2 \times 10^4$ K, and $1 \times 10^4$ K, respectively.Comment: 9 pages, 3 figures in PostScript, latex, accepted for publication on the Astrophysical Journal Letter

Characterization, bioactive compounds and antioxidant potential of three Brazilian fruits.

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Low Energy Electron Point Projection Microscopy of Suspended Graphene, the Ultimate "Microscope Slide"

Point Projection Microscopy (PPM) is used to image suspended graphene using low-energy electrons (100-200eV). Because of the low energies used, the graphene is neither damaged or contaminated by the electron beam. The transparency of graphene is measured to be 74%, equivalent to electron transmission through a sheet as thick as twice the covalent radius of sp^2-bonded carbon. Also observed is rippling in the structure of the suspended graphene, with a wavelength of approximately 26 nm. The interference of the electron beam due to the diffraction off the edge of a graphene knife edge is observed and used to calculate a virtual source size of 4.7 +/- 0.6 Angstroms for the electron emitter. It is demonstrated that graphene can be used as both anode and substrate in PPM in order to avoid distortions due to strong field gradients around nano-scale objects. Graphene can be used to image objects suspended on the sheet using PPM, and in the future, electron holography

The Dwarf Novae of Shortest Period

We present observations of the dwarf novae GW Lib, V844 Her, and DI UMa. Radial velocities of H-alph yield orbital periods of 0.05332 +- 0.00002 d (= 76.78 m) for GW Lib and and 0.054643 +- 0.000007 d (= 78.69 m) for V844 Her. Recently, the orbital period of DI UMa was found to be only 0.054564 +- 0.000002 d (= 78.57 m) by Fried et al. (1999), so these are the three shortest orbital periods among dwarf novae with normal-abundance secondaries. GW Lib has attracted attention as a cataclysmic binary showing apparent ZZ Ceti-type pulsations of the white dwarf primary. Its spectrum shows sharp Balmer emission flanked by strong, broad Balmer absorption, indicating a dominant contribution by white-dwarf light. Analysis of the Balmer absorption profiles is complicated by the unknown residual accretion luminosity and lack of coverage of the high Balmer lines. Our best-fit model atmospheres are marginally hotter than the ZZ Ceti instability strip, in rough agreement with recent ultraviolet results from HST. The spectrum and outburst behavior of GW Lib make it a near twin of WZ Sge, and we estimate it to have a quiescent V absolute magnitude 12. Comparison with archival data reveals proper motion of 65 +- 12 mas/yr. The mean spectrum of V844 Her is typical of SU UMa dwarf novae. We detected superhumps in the 1997 May superoutburst with superhump period = 0.05597 +- 0.00005 d. The spectrum of DI UMa appears normal for a dwarf nova near minimum light. These three dwarf novae have nearly identical short periods but completely dissimilar outburst characteristics. We discuss possible implications.Comment: Accepted for publication in Publications of the Astronomical Society of the Pacific; 16 pages, 6 figure