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Although systematic, quantitative assessment of environmental health risks is a staple of regulatory decision-making, complaints regarding its perceived failures and shortcomings are an intrinsic feature of the policy landscape. In this article, we (a) catalog the classic criticisms of conventional health risk assessment, (b) create a typology that orders the critiques according to their focus on either input errors or output biases, and (c) identify selected allegations that fall within each category. We also note that the risk assessment–risk management paradigm has evolved over the past several decades, partially in accordance with the general direction and spirit of these classic critiques. The debate continues today along familiar lines invoking the traditional critiques and rebuttals outlined here. 相似文献
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Ruxandra Ion L. Telvi Jean-Louis Chaussain Jacques Patrick Barbet Manoel Nunes Anne Safar Marie-Odile Réthoré Marc Fellous Ken McElreavey 《Human genetics》1998,102(2):151-156
In 46,XY individuals, testes are determined by the activity of the SRY gene (sex-determining region Y), located on the short arm of the Ychromosome. The other genetic components of the cascade
that leads to testis formation are unknown and may be located on the Xchromosome or on the autosomes. Evidence for the existence
of several loci associated with failure of male sexual development is indicated by reports of 46,XY gonadal dysgenesis associated
with structural abnormalities of the Xchromosome or of autosomes (chromosomes9, 10, 11 and 17). In this report, we describe
the investigation of a child presenting with multiple congenital abnormalities, mental retardation and partial testicular
failure. The patient had a homogeneous de novo 46,XY,inv dup(9)(pter→p24.1::p21.1 →p23.3::p24.1→qter) chromosome complement.
No deletion was found by either cytogenetic or molecular analysis. The SRY gene and DSS region showed no abnormalities. Southern blotting dosage analysis with 9p probes and fluorescent in situ hybridisation data
indicated that the distal breakpoint of the duplicated fragment was located at 9p24.1, proximal to the SNF2 gene. We therefore suggest that a gene involved in normal testicular development and/or maintenance is present at this position
on chromosome 9.
Received: 20 January 1997 / Accepted: 5 November 1997 相似文献
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J. Komdeur F. Kraaijeveld-Smit K. Kraaijeveld P. Edelaar 《Proceedings. Biological sciences / The Royal Society》1999,266(1433):2075
Extra-pair copulations (EPCs) (copulations outside the pair bond) resulting in extra-pair fertilizations (EPFs) are widespread in birds. To increase reproductive success, males should not only seek EPCs, but also prevent their females from having EPFs. Male Seychelles warblers (Acrocephalus sechellensis) follow their partner closely during the period when these females are most receptive (fertile period). The Seychelles warbler is the first species to offer explicit experimental evidence that mate guarding functions as paternity guarding: in territories where free-living males were induced to stop mate guarding during the pair female''s fertile period, the rates of intrusions by other males and successful EPCs (male mounting female) were significantly higher than those observed in the control group and in the absence of mate guarding the frequency of successful EPCs increased significantly with local male density. Male warblers do not assure their paternity through frequent copulations to devalue any sperm from other males: males do not copulate with their partners immediately following a successful EPC obtained by their partners, the frequency of successful within-pair copulations does not increase with the frequency of successful EPCs and females initiate all successful copulations and are capable of resisting copulation attempts. 相似文献
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Antoine Wystrach Sebastian Schwarz Patrick Schultheiss Guy Beugnon Ken Cheng 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(2):167-179
The Australian desert ant Melophorus bagoti often follows stereotypical routes through a cluttered landscape containing both distant panoramic views and obstacles (plants)
to navigate around. We created an artificial obstacle course for the ants between a feeder and their nest. Landmarks comprised
natural objects in the landscape such as logs, branches, and tussocks. Many ants travelled stereotypical routes home through
the obstacle course in training, threading repeatedly the same gaps in the landmarks. Manipulations altering the relations
between the landmarks and the surrounding panorama, however, affected the routes in two major ways. Both interchanging the
positions of landmarks (transpositions) and displacing the entire landmark set along with the starting position of the ants
(translations) (1) reduced the stereotypicality of the route, and (2) increased turns and meanders during travel. The ants
might have used the entire panorama in view-based travel, or the distal panorama might prime the identification and use of
landmarks en route. Despite the large data set, both options (not mutually exclusive) remain viable. 相似文献