JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. American Society of Mammalogists is collaborating with JSTOR to digitize, preserve and extend access to Journal of Mammalogy.Little is known about the ecology of South American mountain lions (Currier, 1983; Schaller and Crawshaw, 1980; Schaller, 1983). Even in Chile, perhaps the best known country mammalogically in South America (Pine, 1982), most information on this species is anecdotal (Housse, 1953; Miller and Rottman, 1976). Except for the works of Thomas various aspects of the systematics, conservation status, geographical distribution, habitat use, and predatory behavior of Chilean mountain lions, no other published information is presently available. Here we report the first quantitative data on the food habits of mountain lions in Chile.Study sites and material.-In July and August (austral winter) 1983, and October 1983 through January 1984 (spring/summer), we collected mountain lion scats in four sections (Laguna Azul, Laguna Verde, Lago Pehoe, and Administration Headquarters) of Torres del Paine National Park (roughly at 51'01'S, 72?54'W, a 163,000 ha area located 142 km north of Puerto Natales; a map can be seen in Wilson, 1984). This park harbors good-sized populations of the camelid Lama guanicoe (Wilson, 1984) and, because it contains some forested and hilly terrain, offers refuge for the uncommon cervid Hippocamelus bisulcus. Livestock, except for horses and occasional stragglers from outside, has been extirpated.We are confident that the scats examined are from mountain lions. The only potential for misidentification is posed by scats of foxes (Dusicyon sp.) and rheas (Pterocnemia pennata). However, the former are noticeably smaller than mountain lion scats, and the latter contain exclusively plant material. A fraction of the mountain lion scats collected in the park were clearly fresh so that it could be assumed that they contained prey caught during that month. Owing to the small sample size of known-age scats, they were pooled into two categories for analysis (winter, and spring/summer). Those scats which did not appear to be fresh were considered of unknown age (but probably were less than one year old) and treated as a single category. Prey in the scats were recognized by contrasting both bony remains and fur against voucher specimens. Larger prey such as guanacos, deer, horses, cattle, and sheep, were identified mainly on the basis of their hair. A cautionary note is necessary here: mountain lions in the park have been recorded to return up to three times to feed on the large kills (J. R. Rau, pers. comm.; Wilson, 1984); consequently their numerical representation in the mountain lion's diet may be an overestimate. This is not the case for smaller prey, wh...

The potential applications of poly(p‐phenylene vinylene) derivatives and its oligomers in organic electronics have attracted great interest in recent years. In this study, a novel palladium supported on halloysite heterogeneous catalyst (Pd/HNTs) was prepared, characterized and its catalytic activity for obtaining p‐phenylenevinylene oligomers was investigated in the Heck coupling of styrene and 2,5‐diiodo‐1,4‐dimethoxybenzene using conventional and environmentally benign solvents. Thus, in the presence of 0.75 mol% catalyst, the product was obtained in 76% yield using ethanol as solvent. To evaluate the versatility of the Pd/HNTs catalyst, the synthesis of a series of p‐phenylenevinylene oligomers and divinylbenzene derivatives was performed obtaining yields between 58 and 93%. In addition, the catalyst could be recovered and reused for four reaction cycles without significant loss of its catalytic activity. Finally, the photophysical characterization of the synthesized molecules was performed.

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In this work we present a joint experimental and theoretical study of the light emitting properties of (E,E)-2,5-dimethoxy-1,4-bis­[2-(4-carboxylatestyryl)]­benzene, a phenylenevinylene (PV, from now on) derivative in the solid state. Careful crystal growth under different conditions of this PV luminophore yields three different crystals with dissimilar color emissions with maxima ranging between 504 and 565 nm. Single crystal structure elucidations indicate that they correspond to a DMF solvate, denoted 2·DMF (yellow) and two conformational polymorphs named 2α (yellow) and 2β (orange). Analysis of the close contacts and the framework topologies help us to rationalize the different colors observed, not only on the basis of different intramolecular conformations but also of the different intermolecular interactions observed. Particularly, the presence of different C–H···π and π···π interactions in 2α and in 2β polymorphs, respectively, give rise to different supramolecular frameworks with hex and bcu topologies. Theoretical studies reinforce the hypothesis that cooperative π···π interactions in the crystal lattice are responsible for the red-shifted color observed in the polymorph 2β. In fact, in contrast to what is observed with the polymorph 2α, as we incorporate more monomers in the calculations of the optical properties of polymorph 2β, the estimated energy for the vertical excitation from the ground state to the first excited state moves to lower values.

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