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This study examined the foraging behaviour of a resident bird species, the rufous-capped warbler (RCWA, Basileuterus rufifrons). in a shaded-coffee farm in Chiapas, Mexico. Unlike many resident species that use shaded-coffee agroecosystems seasonally. RCWAs do not move to other habitats when migrants are present. RCWA foraging was compared when migrant birds were present (dry season) and absent (wet season). It was hypothesized that RCWAs would exhibit a seasonal foraging niche shift because of resource competition with migrants. Observations from both the canopy and coffee understorey show that RCWAs foraged almost equally in both vegetative layers during the wet season although they were more successful foraging in the canopy. In the dry season, migrants foraged primarily in the canopy and RCWAs shifted so that 80% of RCWA foraging manoeuvres were in the understorey. At that time RCWAs foraged less successfully in both vegetative layers. Avian predation in the dry season was found to reduce densities of arthropods by 47-79% in the canopy, as opposed to 4-5% in the understorey. In the canopy, availability of large (> 5 mm in length) arthropods decreased by 58% from the wet to dry season. Such resource reductions could have caused the RCWA foraging niche shift yet other alternative or additional hypotheses are discussed. Shifts in foraging niche may be a widespread mechanism for some small insectivorous residents to avoid seasonal competition with abundant migrant species.

Rosalie Greenberg Medical Arts Psychotherapy Associates PA, Summit, NJ, USAI read with great interest the article by Bransfield,1 wherein the author reviewed potential contributors to and manifestations of heightened loss of control in Lyme disease patients. As a child psychiatrist living in a Lyme-endemic state, New Jersey, in the USA, I have seen a number of children and adolescents who exhibit significant acute or gradual onset of highly oppositional behaviors often both at home and at school. Refusal to do classwork or homework, heightened paranoia or feeling rejected by others is often present. In addition, they often demonstrate increased irritability, extreme temper tantrums, problems concentrating, elevated impulsivity, sensory hypersensitivity (sound, touch, smell, taste and/or light) and intense emotional lability. Parents describe these behaviors as either a sudden change or a period of worsening of a previous condition, such as attention-deficit hyperactivity disorder or mood disorder. During periods of intense anger over minimal issues, they can appear menacing and threaten to kill a sibling, parent or a friend or state that they want to die themselves. In a recent record review of 69 youth evaluated in my private psychopharmacology practice, 49 of these new patients, without a known history of Lyme disease or other tick-borne disorders, demonstrated evidence of exposure to one or more of the pathogens Borrelia burgdorferi, Bartonella, Babesia, Ehrlichia and Anaplasma on serologic testing performed by multiple laboratories. In addition, 6 of the 69 patients were initially referred because of psychiatric difficulties observed by other physicians during the active treatment of tick-borne infections. Supporting this connection of childhood neuropsychiatric symptoms and tick-borne illness is a recent article looking at 27 youth diagnosed with bipolar disorder I or II, which found that 74% or 20/27 were diagnosed with at least one tick-borne illness based on serologic testing and clinician evaluation.2 Of note, bipolar disorder is a psychiatric illness that carries a high risk of suicide. There appears to be no question that exploration of the association of Lyme disease and tick-borne illnesses with neuropsychiatric symptoms both in children and adults requires more extensive study.View the original paper by Bransfield

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.04.025 Byline: T.A. Hurford (a), B.G. Bills (b)(c), P. Helfenstein (d), R. Greenberg (e), G.V. Hoppa (f), D.P. Hamilton (g) Keywords: Tectonics; Enceladus Abstract: Given the non-spherical shape of Enceladus [], the satellite will experience gravitational torques that will cause it to physically librate as it orbits Saturn. Physical libration would produce a diurnal oscillation in the longitude of Enceladus' tidal bulge, which could have a profound effect on the diurnal tidal stresses experienced by the surface of the satellite. Although Cassini ISS has placed an observational upper limit on the amplitude of Enceladus' libration, smaller amplitudes can still have geologically significant consequences. Here we present the first detailed description of how physical libration affects tidal stresses and how those stresses might then affect geological processes including crack formation and propagation, south polar eruption activity, and tidal heating. Our goal is to provide a framework for testing the hypothesis that geologic features on Enceladus are produced by tidal stresses from diurnal librations of the satellite. Author Affiliation: (a) Planetary Systems Laboratory, NASA Goddard Spaceflight Center, Greenbelt, MD 20771, USA (b) Jet Propulsion Laboratory, Pasadena, CA 90119, USA (c) Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, La Jolla, CA 92093, USA (d) CRSR, Cornell University, Ithaca, NY 14853, USA (e) Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA (f) Raytheon, Woburn, MA 01801, USA (g) Department of Astronomy, University of Maryland, College Park, MD 20742, USA Article History: Received 20 October 2008; Revised 16 March 2009; Accepted 17 April 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.02.036 Byline: T.A. Hurford (a), A.R. Sarid (b), R. Greenberg (c), B.G. Bills (d)(e) Keywords: Europa; Tectonics; Rotational dynamics; Tides; solid body Abstract: Tectonic patterns on Europa are influenced by tidal stress. An important well-recognized component is associated with the orbital eccentricity, which produces a diurnally varying stress as Jupiter's apparent position in Europa's sky oscillates in longitude. Cycloidal lineaments seem to have formed as cracks propagated in this diurnally varying stress field. Maps of theoretical cycloid patterns capture many of the characteristics of the observed distribution on Europa. However, a few details of the observed cycloid distribution have not been reproduced by previous models. Recently, it has been shown that Europa has a finite forced obliquity, so Jupiter's apparent position in Europa's sky will also oscillate in latitude. We explore this new type of diurnal effect on cycloid formation. We find that stress from obliquity may be the key to explaining several characteristics of observed cycloids such as the shape of equator-crossing cycloids and the shift in the crack patterns in the Argadnel Regio region. All of these improvements of the fit between observation and theory seem to require Jupiter crossing Europa's equatorial plane 45[degrees] to 180[degrees] after perijove passage, suggestive of complex orbital dynamics that locks the direction of Europa's pericenter with the direction of the ascending node at the time these cycloids were formed. Author Affiliation: (a) Planetary Systems Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States (b) Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA 94720, United States (c) Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, United States (d) Jet Propulsion Laboratory, Pasadena, CA 90119, United States (e) Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, La Jolla, CA 92093, United States Article History: Received 28 July 2006; Revised 2 February 2009; Accepted 19 February 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2006.08.026 Byline: T.A. Hurford, A.R. Sarid, R. Greenberg Keywords: Europa; Tectonics Abstract: Cycloidal crack patterns on Europa are influenced by tides induced by orbital eccentricity, which in turn is driven by the Laplace orbital resonance. Their shapes potentially record the location of their formation (relative to the direction of Jupiter), as well as the parameters of crack formation. Hoppa et al. [Hoppa, G., Tufts, B.R., Greenberg, R., Geissler, P., 1999a. Icarus 141, 287-298] modeled several cycloid chains using a fixed set of material parameters, but some details did not fit. We now allow material parameters to vary for each arc of an observed cycloid. In general, with minimal variation of model parameters between the arcs, fits are greatly improved. Furthermore, accounting for tidal stress accumulated during non-synchronous rotation, in addition to diurnal stress, allows even better fits. Even with the added freedom in the model our fits allow us to better constrain the location where each cycloid may have formed. Our results support Hoppa et al.'s finding that only a few cracks form ridges per cycle of non-synchronous rotation in the region examined, probably because cracking relieves built up stress until further substantial rotation occurs. Author Affiliation: Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA Article History: Received 14 November 2005; Revised 17 August 2006