What can development policy learn from the history of development?

This article reports the proceedings of a workshop held on 3 June 2010, that aimed to establish a dialogue between historians of agriculture and academics working in development studies. Including papers by historians from the Netherlands, Canada and the UK, and a commentary from the development anthropologist, Paul Richards, the workshop identified a number of themes for further investigation, and confirmed the value of continuing dialogue between historians and policy academics.     

Song-note discriminations in zebra finches (Taeniopygia guttata): Categories and pseudocategories.

Sturdy, Phillmore, and Weisman (1999) developed a simple, reliable procedure for classifying zebra finch (Taeniopygia guttata) song notes into types using exemplar notes from 4 captive North American laboratory colonies. In the present experiment, zebra finches learned true-category song-note discriminations based on Sturdy et al.'s note-type classification faster than pseudocategory discriminations based on random assortments of the same notes. Also, birds in the true-category discrimination were able to sort notes not heard during training into the same categories as the training notes. This evidence suggests that zebra finches accurately sort conspecific song notes into the same open-ended categories as Sturdy et al.'s human observers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanisms of call note-type perception in black-capped chickadees (Poecile atricapillus): Peak shift in a note-type continuum.

We report on operant conditioning and artificial neural network (ANN) simulations aimed at further elucidating mechanisms of black-capped chickadee chick-a-dee call note category perception. Specifically, we tested for differences in the speed of acquisition among different discrimination tasks and, in two selected discrimination groups, searched for evidence of peak shift. Earlier, unreported ANN data were instrumental in providing the motivation for the current set of studies with chickadees and are provided here. The ANNs revealed differences in the speed of learning among note-type discrimination groups that is related to the degree of perceptual similarity among the three note types tested (i.e., A, B, and C notes). In many respects, bird and network results were in agreement (i.e., in the observation of peak shift in the same group), but they also differed in important ways (i.e., all discrimination groups showed differences in speed of learning in simulations but not in chickadees). We suggest that the start, peak and end frequency of the chick-a portion of chick-a-dee call notes, which form a graded but overlapping continuum, may drive the peak shift observed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Open-ended categorization of chick-a-dee calls by black-capped chickadees (Poecile atricapilla).

The authors trained black-capped chickadees (Poecile atricapilla) in an operant discrimination with exemplars of black-capped and Carolina chick-a-dee calls, with the goal of determining whether the birds memorized the calls of conspecifics and heterospecifics or classified the calls by species. Black-capped calls served as both rewarded (S+) and unrewarded (S-) stimuli (the within-category discrimination), whereas Carolina chick-a-dee calls served as S-s (the between-category discrimination) in the black-capped chick-a-dee call S+ group. The Carolina call S+ group had Carolina calls as S+s and S-s (within-category) and black-capped calls as S-s (between-category). Both groups discriminated between call categories faster than within a call category. In 2 subsequent experiments, both S+ groups showed transfer to novel calls and propagation back to between-category calls. The results favor the hypothesis that the acoustically similar social calls of the 2 species constitute separate open-ended categories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prescribing for persistent cough in children

BACKGROUND/AIMS: Both ethanol and gamma aminobutyric acid (GABA) have been reported to inhibit hepatic regenerative activity in the rat. Because alcoholic beverages contain appreciable amounts of GABA, we documented whether the inhibitory effects of alcohol on the liver are derived from ethanol alone or the combination of ethanol plus GABA. METHODS: Adult male Sprague-Dawley rats (n=6/group) were treated with either ethanol (3 g/kg), GABA (500 mg/kg) or ethanol plus GABA (3 kg and 500 mg/kg, respectively), beginning 1 h prior to a 70% partial hepatectomy and continued every 4 h thereafter for a total of 24 h. Rats were then sacrificed and hepatic regenerative activity was documented by 3H-thymidine incorporation into hepatic DNA. RESULTS: DNA synthesis was significantly inhibited by ethanol (-37%, p<0.005) and GABA (-19%, p<0.05). Maximum inhibition was achieved with the combination of ethanol plus GABA (-52%, p<0.001). To determine whether the additive effects of ethanol plus GABA were mediated by ethanol-induced enhancement of hepatic GABA(A) receptor activity, additional rats (n=6/group) receiving the combination of ethanol plus GABA were pre-treated with a single injection of either ciprofloxacin (50 mg/kg), a GABA(A) receptor antagonist, or an equal volume of saline. In these experiments, ciprofloxacin pre-treatment prevented the inhibitory effects of the ethanol plus GABA combination. CONCLUSIONS: The results of this study indicate that the combination of ethanol plus GABA has a greater inhibitory effect on hepatic DNA synthesis following partial hepatectomy than ethanol alone. The clinical implication of this finding is that, when standardized for ethanol content, not all alcoholic beverages would be expected to have the same inhibitory effect on hepatic regeneration.     

Note types, harmonic structure, and note order in the songs of zebra finches (Taeniopygia guttata)..

Zebra finch (Taeniopygia guttata) song notes are acoustically complex, rich in harmonic structure, and variable among birds. This article provides simple, reliable methods for classifying zebra finch song notes into types, for describing the harmonic structure of song notes, and for determining the order of notes in song motifs in samples from 4 captive North American laboratory colonies. Using the note-type classification scheme, 2 observers sorted 90% of readable song notes into 5 types with 94% interobserver agreement. Examination of song-note power spectra revealed that reduced harmonics were a common feature of zebra finch song notes. Finally, an analysis of zebra finches' songs suggests that males produce the notes in their motifs in a consistent but not stereotyped (invariant) order. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acoustic Mechanisms of Note-Type Perception in Black-Capped Chickadee (Poecile atricapillus) Calls.

Acoustic communication in black-capped chickadees (Poecile atricapillus) has been studied intensively, the "chick-a-dee" call being among the most well described. This call consists of 4 note types; chickadees perceive these notes as open-ended categories and do so in a continuous manner, with As more similar to Bs and Bs more similar to Cs. Acoustic features contributing to the note-type differentiation are unknown. Recent analyses suggested that certain acoustic features may play a role in note-type classification. Here, the authors tested black-capped chickadees in an operant-conditioning paradigm to determine which features were controlling note-type perception. The results suggest that the note pitch and the frequency modulation in the initial portion of the note control the perception of note types. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Call-note discriminations in black-capped chickadees (Poecile atricapillus).

Bioacousticians (M. S. Ficken, S. R. Ficken, & S. R. Witken, 1978) classified black-capped chickadee call notes from the chick-a-dee call complex into 4 note types (A, B, C, and D) identified from sound spectrograms. In Experiment 1, chickadees (Poecile atricapillus) learned operant auditory discriminations both within and between the 4 note types but learned the between note-type discrimination significantly faster. In Experiment 2, when the original, unrewarded between-category exemplars were replaced with novel, rewarded exemplars of these same categories, chickadees showed transfer of inhibitory stimulus control to the novel exemplars. In Experiment 3, when novel exemplars were replaced by the original exemplars, chickadees showed propagation of positive stimulus control back to the original exemplars. This evidence suggests that chickadees and bioacousticians accurately sort conspecific call notes into the same open-ended categories (R. J. Hernstein, 1990). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Massive lower gastrointestinal haemorrhage secondary to metastatic squamous cell carcinoma of the lung

Clinically significant symptoms due to gastrointestinal metastases from primary lung cancers is rare. A case of life-threatening lower gastrointestinal haemorrhage secondary to metastatic squamous cell carcinoma of the lung is reported. Previous reports of such metastases are reviewed, with reference to management and prognosis. After resection of colonic metastases from squamous cell lung cancer, survival is similar to that for primary disease. It is suggested that patients with known or suspected squamous cell lung cancer presenting with lower gastrointestinal symptoms be managed as aggressively as those with no previous history of disease.     

Copper and zinc water quality standards under the EU Water Framework Directive: the use of a tiered approach to estimate the levels of failure

Environmental quality standards are an important tool for assessing the chemical quality of water bodies under the Water Framework Directive. However, there must be confidence in assessments of any failure to avoid disproportionate investment in unnecessary risk reduction. Metals present a number of unique challenges for environmental regulators in that they are naturally occurring and their ecotoxicology is driven, in part, by the physico-chemical conditions of the water body in which they are present. This paper describes the use of a tiered approach that could be adopted to assess compliance with any future environmental quality standards for metals under the Water Framework Directive. Through this approach, the use of background concentrations is considered and also bioavailability via the use of biotic ligand models. This assessment is based on an analysis of routine Environment Agency chemical monitoring data combined with biological indices to support results of the approach. Using copper and zinc as examples, it is shown that it is important to take account of background concentrations and the bioavailability of metals, otherwise the risk of impact from metals may be significantly overestimated. The approach presented here provides a methodology by which regulators and the regulated community may implement surface water standards for metals under the Water Framework Directive.