Predator-induced stress makes the pesticide carbaryl more deadly to gray treefrog tadpoles (Hyla versicolor)

Global declines in amphibians likely have multiple causes, including widespread pesticide use. Our knowledge of pesticide effects on amphibians is largely limited to short-term (4-d) toxicity tests conducted under highly artificial conditions to determine lethal concentrations (LC50). We found that if we used slightly longer exposure times (10–16 d), low concentrations of the pesticide carbaryl (3–4% of LC504-d) killed 10–60% of gray treefrog (Hyla versicolor) tadpoles. If predatory cues also were present, the pesticide became 2–4 times more lethal, killing 60–98% of tadpoles. Thus, under more realistic conditions of increased exposure times and predatory stress, current application rates for carbaryl can potentially devastate gray treefrog populations. Further, because predator-induced stress is ubiquitous in animals and carbaryl's mode of action is common to many pesticides, these negative impacts may be widespread in nature.

Del ciborg a la realidad aumentada. coloquio Gray - Mentor - Figueroa - Sarriera

La publicación en 1985 del Manifiesto ciborg, de Donna Haraway, tuvo un efecto explosivo en los estudios de ciencia, tecnología y sociedad. Sirvió como catalizador de una ruptura definitiva y largamente augurada con los estudios de historia y filosofía y de la ciencia tradicionales y supuso una apertura a territorios conceptuales novedosos, en los que se entreveraban la informática, la filosofía, la teoría literaria, la semiótica o la ciencia ficción. Chris H. Gray, Heidi Sarriera-Figueroa y Steven Mentor, autores de The Cyborg Handbook, repasan en este coloquio moderado por Ángel Gordo e Igor Sádaba la evolución de este campo de estudios.

Planning for the Future: Gray Water Supply as a Conservation Measure for a Key Water Provider in Douglas County, Colorado

Diminishing water in the Denver Basin aquifers requires Parker Water and Sanitation District plan for the future to ensure availability of supply. Water conservation is one approach to prolonging the life of the aquifers. Homeowner installed gray water systems will help conserve 25 percent of the water needed and reduce the need to pump ground water for irrigation. Non-potable water through gray water systems will reduce the demand on the supplier. Gray water use will prolong a potable supply to Parker for years ahead. For this plan to be effective, Colorado regulations must change to allow gray water use. This goal will be achieved as the mind-set about water conservation shifts and water suppliers and consumers demand modification to policies.

Neotropical deer (Cervidae) : Part I. Pudus, genus Pudu Gray / Philip Hershkovitz.

n.s. no.11(1982)

Letters from William Croswell to the Harrison Gray Otis, 1824-1825

Two leaves containing drafts of brief notes that accompanied letters for Harvard Corporation between April 1824 and April 1825.

[Admittatur of Thomas Gray (Harvard AB 1790)], 1786 July 15

Published copy of the 1790 College Laws, bound in modern board binding, with the admittatur of undergraduate Thomas Gray signed by President Joseph Willard on July 15, 1786.

Catalogue of shield reptiles in the collection of the British Museum / by John Edward Gray.

pt.1

A flora of North America :containing abridged descriptions of all the known indigenous and naturalized plants growing north of Mexico, arranged according to the natural system /by John Torrey and Asa Gray.

v.2 (1841-1843)

[ Warrant for the arrest of Samuel Gray for debt], 1769

A warrant for the arrest and sale of all assets of Gray who was found to owe another merchant Alexander Hill in a recent trial. Also includes appraisal of property by Fairfield and Salter and statement by Sheriff Cudworth.