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Objectives Cortical auditory evoked potentials (CAEPs) to tones and speech sounds were obtained in infants to: 1) further knowledge of auditory development above the level of the brainstem during the first year of life; 2) establish CAEP input-output functions for tonal and speech stimuli as a function of stimulus level and to 3) elaborate the data-base that establishes CAEP in infants tested while awake using clinically relevant stimuli, thus providing methodology that would have translation to pediatric audiological assessment. Hypotheses concerning CAEP development were that the latency and amplitude input-output functions would reflect immaturity in encoding stimulus level. In a second experiment, infants were tested with the same stimuli used to evoke the CAEPs. Thresholds for these stimuli were determined using observer-based psychophysical techniques. The hypothesis was that the behavioral thresholds would be correlated with CAEP input-output functions because of shared cortical response areas known to be active in sound detection. Design 36 infants, between the ages of 4-12 months (mean= 8 months, s.d.=1.8 months) and 9 young adults (mean age 21 years) with normal hearing were tested. First, CAEPs amplitude and latency input-output functions were obtained for 4 tone bursts and 7 speech tokens. The tone bursts stimuli were 50 ms tokens of pure tones at 0.5, 1.0, 2.0 and 4.0 kHz. The speech sound tokens, /a/, /i/, /o/, /u/, /m/, /s/, and /∫/, were created from natural speech samples and were also 50 ms in duration. CAEPs were obtained for tone burst and speech token stimuli at 10 dB level decrements in descending order from 70 dB SPL. All CAEP tests were completed while the infants were awake and engaged in quiet play. For the second experiment, observer-based psychophysical methods were used to establish perceptual threshold for the same speech sound and tone tokens. Results Infant CAEP component latencies were prolonged by 100-150 ms in comparison to adults. CAEP latency-intensity input output functions were steeper in infants compared to adults. CAEP amplitude growth functions with respect to stimulus SPL are adult-like at this age, particularly for the earliest component, P1-N1. Infant perceptual thresholds were elevated with respect to those found in adults. Furthermore, perceptual thresholds were higher, on average, than levels at which CAEPs could be obtained. When CAEP amplitudes were plotted with respect to perceptual threshold (dB SL), the infant CAEP amplitude growth slopes were steeper than in adults. Conclusions Although CAEP latencies indicate immaturity in neural transmission at the level of the cortex, amplitude growth with respect to stimulus SPL is adult-like at this age, particularly for the earliest component, P1-N1. The latency and amplitude input-output functions may provide additional information as to how infants perceive stimulus level. The reasons for the discrepancy between electrophysiologic and perceptual threshold may be due to immaturity in perceptual temporal resoluti...

Evidence is presented for the first time showing that semicarbazide (SEM) is a minor thermal decomposition product of the blowing agent azodicarbonamide (ADC). A novel direct analytical method based on liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESIMS/MS) has been developed to determine SEM in foamed polyvinyl chloride (PVC) seals of metal lids, as well as in commercially available ADC. The direct LC-MS/MS method for gaskets entails extraction of the gaskets in hot water, addition of ((15)N(2)(13)C)-SEM as internal standard, and injection of an aliquot directly into the LC-MS system, achieving good sensitivity (S/N = 348 for 2 ng injected on-column) and monitoring three characteristic mass transitions (m/z 76-->31; 76 -->44; 76-->59). Semicarbazide can be detected in thermally treated ADC, reaching up to 0.93 mmol mol(-1) at 220 degrees C, as determined by the direct LC-MS/MS method. This new method is also compared to the classical derivatization method using 2-nitrobenzaldehyde (2-NBA) that is routinely employed to determine SEM as an indicator of the usage of the antimicrobial drug nitrofurazone, the use of which is not authorized in the European Union (EU). Both methods revealed proportional results, with approx. 3-fold higher levels recorded by the direct SEM approach, probably due to differences in the extraction procedures used. A limited survey of plastic seals from used press twist and twist-off metal lids on food jars (non-foamed and foamed) revealed levels of SEM ranging from 2 to 8689 microg kg(-1)(average = 1593 microg kg(-1), n= 57 determinations).

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This article assesses why Eurosceptic national parties form groups in the European Parliament (EP) and examines in what ways two of these groups -the European Conservatives and Reformists (ECR) and Europe of Freedom and Democracy (EFD) -operate in the EP. It draws on interviews with politicians and group officials, roll-call votes and expert judgement data. We look at the group formation process with a focus on the British Conservatives and UK Independence Party (UKIP) and find that the ECR was created with a mixture of policy-seeking and party management aims. UKIP's interest in the EFD is largely on the basis of distinctive practical advantages, such as resources for political campaigns. We provide evidence that hard Eurosceptic and regionalist niche parties in the EP struggle to agree with each other in roll-call votes on a range of subjects. Finally, we show that the hard and soft Eurosceptic parties studied here go about policy-seeking in different ways in the EP in line with their differing principles about the integration process.

The Conservative Party became more united around a soft Eurosceptic position in opposition, but internal divisions are evident on the scale and pace of change to the UK's relationship with the EU. • Conservative Party leaders have employed a range of methods to manage intra-party dissent on European integration: intervention in candidate selection, patronage, discipline, policy compromises, permitting low-cost dissent, referendum pledges and reducing issue salience. • Dissent on European integration tends to be higher when the Conservatives are in office because governing parties cannot individually control the EU agenda, must take difficult decisions and may have to sacrifice their preferred positions to broker compromises. • Eurosceptic dissent has increased because Conservative policy has been diluted in coalition and the crisis in the Eurozone has raised the salience of the EU issue, but Eurosceptic rebels are not a cohesive group and this limits their influence. Divisions on European integration were prominent in the ConservativeParty in the 1990s, but abated in opposition. In this period, the party became more cohesive in terms of attitudes on Europe as it embraced soft Euroscepticism. However, differences over the desired scale and pace of changes to Britain's relationship with the European Union saw dissent increase as the party entered coalition government with the Liberal Democrats. This article examines the effectiveness of various approaches to management of dissent on Europe utilised by the party leadership: intervention in candidate selection; patronage and discipline; permitting limited dissent; policy compromise and deferred decisions; pledging referendums; and agenda setting and issue salience. It shows that intra-party divisions on European integration are particularly difficult to manage and suggests that dissent on the issue may often be higher in governing parties than those in opposition.

Given the considerable increase in its powers over recent decades this paper asks how far the European Parliament (EP) is an attractive place to build a legislative career.Using a theory of MEPs as policy-seekers, it shows that MEPs are indeed building careers in this supranational institution. Turnover is in decline in the EP and on its committees, average length of service has increased and greater proportions of MEPs aspire to stay than previously. Looking at the 30 years since direct elections began, policy influence and office benefits are associated with lower likelihood of exiting the EP while being on the geographical periphery of the EU makes MEPs more likely to leave. KEY WORDS

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