bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of focused auditory attention on cochlear activity in humans
Authors: Maison Stéphane , Micheyl Christophe , Collet Lionel
Published: December 2004

The mammalian auditory system contains descending pathways that originate in the cortex and relay at various intermediate levels before reaching the peripheral sensory organ of Corti. The last link in this chain consists of the olivocochlear bundle. The activity of this bundle can be measured through otoacoustic emissions, which are acoustic signatures of the cochlear biomechanical activity. In the present study, it was hypothesized that frequency‐specific activation of the olivocochlear bundle in the contralateral ear would show up as frequency‐specific variations in otoacoustic emission amplitude in the ipsilateral ear. Two groups of young adult subjects participated in this experiment. Evoked otoacoustic emissions were recorded in the ipsilateral ear at two test frequencies (1 and 2 kHz). Subjects had to detect probe tones at a given frequency in background noise in the contralateral ear. Larger efferent activation was measured at test frequencies on which attention is focused. This result provides evidence for an influence of attention on the auditory periphery via descending projections.
Independent manipulation of stimulus change and unexpectedness dissociates indices of the orienting response
Authors: Niepel Michael
Published: December 2004

Results obtained with the standard repetition‐change paradigm of orienting research cannot be attributed unambiguously to either stimulus change or to unexpectedness. By adding announcement conditions, in which participants were told about an impending stimulus change, these two factors were disentangled. In Experiment 1, reaction times (RTs) were longer and ratings of surprise were higher with unannounced than with announced stimulus change. In contrast, larger skin conductance response (SCR) magnitudes occurred following change, irrespective of its congruence with participants' expectations. Experiment 2 replicated the results for SCR magnitude and, furthermore, revealed the same pattern of results for the evoked cardiac response. Surprise ratings again reflected the unexpectedness of stimulus presentations. The dissociation between RT and autonomic measures provides difficulties for resource allocation accounts of the orienting response.
Assessing supraspinal modulation of pain perception in individuals at risk for hypertension
Authors: France Christopher R. , Suchowiecki Shannon
Published: December 2004

In this study we tested the hypothesis that hypoalgesia in individuals at risk for hypertension is related to enhanced activation of supraspinal pain modulation systems. Supraspinal inhibition of pain signals was assessed using a diffuse noxious inhibitory control paradigm, in which a noxious conditioning stimulus was used to suppress pain in response to a noxious test stimulus applied to a remote area of the body. Specifically, the nociceptive flexion reflex (NFR) was assessed in 113 healthy young adults before, during, and after exposure to forearm tourniquet ischemia. Consistent with previous evidence of hypoalgesia in individuals at risk for hypertension, offspring of hypertensive individuals exhibited significantly higher NFR thresholds than offspring of normotensive persons. Although NFR activity was significantly decreased in all participants during concomitant application of forearm ischemia, the degree of attenuation of NFR activity was not significantly different as a function of risk for hypertension.
Early educational and health enrichment at age 3–5 years is associated with increased autonomic and central nervous system arousal and orienting at age 11 years: Evidence from the Mauritius Child Health Project
Authors: Raine Adrian , Venables Peter H. , Dalais Cyril , Mellingen Kjetil , Reynolds Chandra , Mednick Sarnoff A.
Published: December 2004

Little is known about the effects of environmental enrichment on psychophysiological measures of arousal and orienting in humans. This study tests the hypothesis that early educational and health enrichment is associated with long‐term increases in psychophysiological orienting and arousal. One hundred children were experimentally assigned to a two‐year enriched nursery school intervention at ages 3–5 years and matched at age 3 years on psychophysiological measures, gender, and ethnicity to 100 comparisons who received the normal educational experience. Children were retested 6–8 years later at age 11 years on skin conductance (SC) and electroencephalogram (EEG) measures of arousal and attention during pre‐ and postexperimental rest periods and during the continuous performance task. Nursery enrichment was associated with increased SC amplitudes, faster SC rise times, faster SC recovery times, and less slow‐wave EEG during both rest and CPT conditions. This is believed to be the first study to show that early environmental enrichment is associated with long‐term increases in psychophysiological orienting and arousal in humans. Results draw attention to the important influence of the early environment in shaping later psychophysiological functioning.
Attentional set effects on spinal and supraspinal responses to pain
Authors: Dowman Robert
Published: December 2004

The effects of attentional set on subjective magnitude ratings, spinal reflexes, and somatosensory evoked potentials (SEP) elicited by innocuous and painful sural nerve stimulation were investigated in 24 subjects. Cuing stimuli informed subjects as to whether a visual identification or a somatosensory rating task would follow. Twenty percent of the trials were invalidly cued, where the subjects were expecting a visual stimulus but were given a sural nerve stimulus and vice versa. Subjective magnitude ratings were lower in the invalidly cued condition than the validly cued condition. Attentional set had no effect on innocuous‐related spinal or early cortical responses, nor on the spinal nociceptive withdrawal reflex. The pain‐related negative difference potential (NDP) and P2 component of the SEP were largest in the invalidly cued condition. These results provide further support for our hypothesis that the NDP is generated in part by the anterior cingulate, and suggest that the anterior cingulate response to pain reflects non‐pain‐specific cognitive processes (e.g., orienting attention towards important stimuli in the environment and/or response competition) and not some aspect of the pain experience. The effects of attentional set on the pain‐related P2 suggests that it might correspond to the P3a event‐related potential. If this is the case, the pain‐related P2 could serve as a useful index of neural processes involved in the cognitive‐evaluative aspect of pain.
Affective reactions to briefly presented pictures
Authors: Codispoti Maurizio , Bradley Margaret M. , Lang Peter J.
Published: December 2004

Affective reactions to briefly presented pictures were investigated to determine whether fleeting stimuli engage the motivational systems mediating emotional responses. Emotional and neutral pictures were presented for 500 ms; heart rate, skin conductance, corrugator EMG, and the evoked startle reflex were measured. The time course of reflex modulation was similar to that obtained with longer (6 s) presentations, suggesting that picture processing continues in the absence of a sensory stimulus. Affective reactions found with more sustained presentation were also obtained, with more corrugator EMG activity for unpleasant pictures, and greater skin conductance reactivity for emotional pictures. Heart rate modulation, however, appears to rely on the presence of a sensory stimulus. The data also suggest that brief presentations of unpleasant pictures may result in less defensive activation than sustained presentation.
Pediatric impedance cardiography: Temporal stability and intertask consistency
Authors: McGrath Jennifer J. , O'Brien William H.
Published: December 2004

The pathogenic processes responsible for cardiovascular disease have their origins in childhood. Although children's measures of heart rate and blood pressure have been found to be reliable, the reliability of impedance cardiography derived measures have not been evaluated. Thirty‐three children, ages 8–11 participated in two sessions. Stressors included serial subtraction, isometric handgrip, and mirror‐image tracing. Results indicated the impedance measures showed moderately high temporal stability (average scores ravg= .74; difference scores ravg= .53) and intertask consistency (average scores ravg= .78; difference scores ravg= .53). Blood pressure demonstrated the lowest reliability; Heather index, preejection period, and stroke volume demonstrated the highest. These findings suggest children's cardiovascular reactivity to laboratory stressors can be reliably and consistently assessed using impedance cardiography.
Comparison between the Fourier and Wavelet methods of spectral analysis applied to stationary and nonstationary heart period data
Authors: Houtveen Jan H. , Molenaar Peter C.M.
Published: December 2004

The aim of this study was to assess the error made by violating the assumption of stationarity when using Fourier analysis for spectral decomposition of heart period power. A comparison was made between using Fourier and Wavelet analysis (the latter being a relatively new method without the assumption of stationarity). Both methods were compared separately for stationary and nonstationary segments. An ambulatory device was used to measure the heart period data of 40 young and healthy participants during a psychological stress task and during periods of rest. Surprisingly small differences (<1%) were found between the results of both methods, with differences being slightly larger for the nonstationary segments. It is concluded that both methods perform almost identically for computation of heart period power values. Thus, the Wavelet method is only superior for analyzing heart period data when additional analyses in the time‐frequency domain are required.
Nonspatial intermodal selective attention is mediated by sensory brain areas: Evidence from event‐related potentials
Authors: Talsma Durk , Kok Albert
Published: December 2004

The present study focuses on the question of whether inter‐ and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while subjects were presented a random sequence of visual and auditory stimuli. They were instructed to attend to nonspatial attributes of either auditory or visual stimuli and to detect occasional target stimuli within the attended channel. An occipital selection negativity was found for intramodal attention to visual stimuli. Visual intermodal attention was also manifested in a similar negativity. A symmetrical dipole pair in the medial inferior occipital areas could account for the intramodal effects. Dipole pairs for the intermodal attention effect had a slightly more posterior location compared to the dipole pair for the intramodal effect. Auditory intermodal attention was manifested in an early enhanced negativity overlapping with the N1 and P2 components, which was localized using a symmetrical dipole pair in the lateral auditory cortex. The onset of the intramodal attention effect was somewhat later (around 200 ms), and was reflected in a frontal processing negativity. The present results indicate that intra‐ and intermodal forms of attention were indeed similar for visual stimuli. Auditory data suggest the involvement of multiple brain areas.
Modulation of respiratory sinus arrhythmia by respiration rate and volume: Stability across posture and volume variations
Authors: Ritz Thomas , Thöns Miriam , Dahme Bernhard
Published: December 2004

We tested the assumption that the slope of the within‐individual regression equation of respiratory sinus arrhythmia (RSA) normalized by tidal volume (VT) upon respiratory cycle length (TTOT) can characterize ventilatory RSA modulation independent of cardiac vagal tone, whereas the intercept is varying as a function of vagal tone. We also explored whether a variation of VT is necessary to estimate slopes reliably. Four 3‐min sequences paced at 8–18 cycles/min were performed supine and standing. Participants also breathed the same sequences in supine posture with voluntarily varying VT. The mean slope of RSA/VT upon TTOT was identical, and the mean intercept was lower for standing than supine (spontaneous VT) conditions. Stability of slopes was low between body postures, and was higher between spontaneous VT versus varying VT at the same body posture. The regression of RSA/VT upon TTOT allows for a valid estimation of ventilatory influences on RSA.
ERD as an index of anticipatory attention? Effects of stimulus degradation
Authors: Bastiaansen Marcel C.M. , Böcker Koen B.E. , Brunia Cornelis H.M.
Published: December 2004

Previous research has suggested that the stimulus‐preceding negativity (SPN) is largely independent of stimulus modality. In contrast, the scalp topography of the event‐related desynchronization (ERD) related to the anticipation of stimuli providing knowledge of results (KR) is modality dependent. These findings, combined with functional SPN research, lead to the hypothesis that anticipatory ERD reflects anticipatory attention, whereas the SPN mainly depends on the affective‐motivational properties of the anticipated stimulus. To further investigate the prestimulus ERD, and compare this measure with the SPN, 12 participants performed a time‐estimation task, and were informed about the quality of their time estimation by an auditory or a visual stimulus providing KR. The KR stimuli could be either intact or degraded.

Auditory degraded KR stimuli were less effective than other KR stimuli in guiding subsequent behavior, and were preceded by a larger SPN. There were no effects of degradation on the SPN in the visual modality. Preceding auditory KR stimuli no ERD was present, whereas preceding visual stimuli an occipital ERD was found. However, contrary to expectation, the latter was larger preceding intact than preceding degraded stimuli. It is concluded that the data largely agree with an interpretation of the pre‐KR SPN as a reflection of the anticipation of the affective‐motivational value of KR stimuli, and of the prestimulus ERD as a perceptual anticipatory attention process.
The effects of feeding on the electroencephalogram in 3‐ and 6‐month‐old infants
Authors: Lehtonen Johannes , Könönen Mervi , Purhonen Maija , Partanen Juhani , Saarikoski Seppo
Published: December 2004

The human infant's neurophysiological responses to feeding are poorly understood. We found recently a significant increase of EEG amplitude in the newborn during nutritive feeding, but not during pacifier sucking. In this study, we report EEG responses to feeding in 13 infants at the ages of 3 and 6 months. The undifferentiated response of the newborn was found to wane until the age of 3 months, whereas in 6‐month‐old infants, relatively abundant rhythmic 3–5 Hz theta activity was recorded during feeding with an amplitude maximum in right posterior areas. Cessation of feeding was followed by cessation of theta activity. The rhythmic 3–5 Hz theta response to feeding is likely to represent emotional arousal, as it is similar to previous findings showing posterior theta increase in other settings connected with emotional arousal in infants.
The temporal stability of electrodermal variables over a one‐year period in patients with recent‐onset schizophrenia and in normal subjects
Authors: Schell Anne M. , Dawson Michael E. , Nuechterlein Keith H. , Subotnik Kenneth L. , Ventura Joseph
Published: December 2004

Test–retest stability of electrodermal (EDA) variables indexing both general autonomic arousal (e.g., skin conductance level, number of nonspecific skin conductance responses) and attention to external stimuli (e.g., number of skin conductance orienting responses, electrodermal responder/nonresponder status) was assessed in 71 young, recent‐onset schizophrenia patients and 36 demographically matched normal subjects. Significant stability over a 1‐year period was found for both patients and normal subjects for most EDA variables and for responder/nonresponder status, with test–retest correlations generally being higher for normal subjects. The lower reliability for patients was not attributable to symptomatic fluctuations during the follow‐up period and may reflect poorer arousal regulation among the patients. Among measures of responding to nontask stimuli, a simple count of the number of orienting responses occurring was more stable than was a traditional trials‐to‐habituation measure.
Energy resource depletion, ability perception, and cardiovascular response to behavioral challenge
Authors: Wright Rex A. , Penacerrada Diane K.
Published: December 2004

This study examined cardiovascular effects of energy resource depletion. Participants first made a series of easy or difficult grips with their right or left hand. They then made and held a moderately difficult dynamometer grip with their right hand while measures of blood pressure and heart rate were taken. As expected, systolic blood pressure responses during the second task period were greater when the first task was difficult than when it was easy if the first task was performed with the right hand, but not if the first task was performed with the left hand. The data support the view that ability perception and, thus, cardiovascular responsiveness vary with relevant energy stores.
Electrical shocks to the arm elicit and inhibit startle eyeblinks
Authors: Blumenthal Terry D. , Swerdlow Charles D.
Published: December 2004

The present study evaluated the ability of a weak electrical prepulse to modify startle caused by a more intense shock. Painful electrical shocks (150 V, 0.5 ms duration) were presented to the upper arm of college student participants, preceded on some trials by a weaker shock (0.5 ms duration, at perceptual threshold) at the same location. Intense shocks elicited eyeblink reflexes, and these eyeblinks were inhibited by weak electrical prepulses. These data suggest that the inclusion of prepulses immediately preceding painful therapeutic shocks, such as those generated by an implanted cardioverter‐defibrillator, might be capable of reducing the startle response generated by that therapeutic shock.
Comparison of finger plethysmograph to ECG in the measurement of heart rate variability
Authors: Giardino Nicholas D. , Lehrer Paul M. , Edelberg Robert
Published: December 2004

Two experiments compared finger plethysmograph (FP) to electrocardiogram (ECG) in providing accurate heart periods for use in heart rate variability (HRV) calculations. In Experiment 1, simultaneous ECG and FP recordings were taken from 16 healthy subjects at rest. In Experiment 2, 10 additional healthy subjects were recorded at rest and during the Stroop Color‐Word Test. In both studies, high correlations were found between FP‐derived and ECG‐derived band variance for high and low frequency HRV at rest. But, during the Stroop task, correlations were strongly diminished. In addition, under both conditions, HRV measures were significantly higher using the FP signal. Thus, FP may be adequate for determining HRV at rest, but, for experimental use, ECG may still be recommended. Nonetheless, further studies that include test–retest reliability assessment of both data collection techniques are warranted before a more certain determination can be made.
Variability of sleep parameters across multiple laboratory sessions in healthy young subjects: The “very first night effect”
Authors: Lorenzo José‐Luis , Barbanoj Manuel‐José
Published: December 2004

Many studies have been carried out to assess the variability of sleep parameters. The first night effect is one of the most important factors in this variability and has been extensively studied. However, the readaptation phenomenon when subjects returned to the sleep laboratory after spending a certain period of time at home has been not systematically evaluated. To investigate this phenomenon across multiple sleep laboratory sessions, polysomnographic data from 12 healthy young subjects for 12 nights (three periods each of 4 consecutive nights, with a minimum of 1 month between them) were collected. The first night effect was present only in the first night of the first period (“very first night”) and was significant only for REM sleep‐related variables. We conclude that the results from the first nights of consecutive periods within a specific protocol with healthy young subjects need not be discarded in subsequent analyses.
Toward a chronopsychophysiology of mental rotation
Authors: Heil Martin , Rolke Bettina
Published: December 2004

In a parity judgment task, the ERPs at parietal electrode sites become the more negative the more mental rotation has to be executed. In two experiments, it was investigated whether a temporal relationship exists between the onset of this amplitude modulation and the moment when mental rotation is executed. Therefore, the duration of processing stages located before mental rotation was manipulated. The amplitude modulation was delayed when either the perceptual quality of the stimulus was reduced (Experiment 1) or when character discrimination was more difficult (Experiment 2). The results suggest that the onset of the rotation‐related negativity might be used as a chronopsychophysiological marker for the onset of the cognitive process of mental rotation.
The functional significance of ERP effects during mental rotation
Authors: Heil Martin
Published: December 2004

In a parity judgment task, the ERPs at parietal electrode sites become more negative as more mental rotation has to be executed. This article provides a review of the empirical evidence regarding this amplitude modulation. More specifically, experiments are reported that validate both the functional relationship between mental rotation and the amplitude modulation as well as the temporal relationship both in single‐ and in dual‐task situations. Additionally, ERP effects are reported in the psychological refractory period (PRP) paradigm with mental rotation as the second task. Finally, unresolved issues are discussed that, I hope, might stimulate future research.
Influence of control and physical effort on cardiovascular reactivity to a video game task
Authors: Weinstein Suzanne E. , Quigley Karen S. , Mordkoff J. Toby
Published: December 2004

This study investigated the influences of both perceived control and physical effort on cardiovascular reactivity. Undergraduates (N = 32) played a video game task interrupted by aversive noise. Perceived control of the noise was manipulated by instructions indicating the presence or absence of a contingency between performance and noise presentations. Physical effort was manipulated by controlling the physical force required to perform the task. There was a significant main effect of control on systolic blood pressure (SBP) and total peripheral resistance (TPR), with both increasing more during low than high control conditions. The results suggest that high perceived control over aversive noise in an effortful task reduces SBP and TPR reactivity relative to low perceived control. The results are consistent with the idea that control buffers the reactivity associated with task performance under aversive conditions.
Variability in AC amplifier distortions: Estimation and correction
Authors: Joyce C.A. , Gorodnitsky I.F. , Teder‐sälejärvi W.A. , King J.W. , Kutas M.
Published: December 2004

AC amplifiers can introduce significant distortions into the low frequency and DC components of recorded electrophysiological data such as event‐related potentials (ERPs). Methods for correcting such distortions (i.e., estimating the waveform of the original data) after the data have been amplified and recorded rely on an accurate estimate of the amplifier's time constant (TC). We show that the filter characteristics of AC amplifiers in at least some commercially available ERP recording instruments may vary considerably across individual channels, even when each houses an identical AC amplifier circuit. Clearly, distortion correction methods must take this variability into account. We propose an empirical means of estimating the correct TC value. This approach yields more accurate correction than those based on TCs calculated analytically.
Hemodynamic response patterns: Responder type differences in reactivity and recovery
Authors: Kline Keith A. , Saab Patrice G. , Llabre Maria M. , Spitzer Susan B. , Evans Jovier D. , McDonald Paige A. Green , Schneiderman Neil
Published: December 2004

We examined whether responder type groups reflecting patterns of hemodynamic reactivity might also differ in recovery responses. Cardiac output (CO), total peripheral resistance (TPR), systolic and diastolic blood pressure, heart rate, and Heather index were assessed at rest and during speech and cold pressor tasks in young adults. Participants (n= 152) were classified as myocardial, vascular, or mixed‐mild responders based on CO and TPR responses to speech presentation. Vascular responders exhibited slower CO and TPR speech recovery than the myocardial and/or mixed‐mild groups. Responder type differences in reactivity showed limited task‐generalizability. The sustained vascular response pattern of the vascular group is consistent with that seen in hypertension. In light of associations of heightened TPR with markers of disease risk, this suggests potentially negative health implications for vascular responders.
Stability of children's and adolescents' hemodynamic responses to psychological challenge: A three‐year longitudinal study of a multiethnic cohort of boys and girls
Authors: Matthews Karen A. , Salomon Kristen , Kenyon Karen , Allen Michael T.
Published: December 2004

This report evaluated (a) the temporal stability of hemodynamic responses to three tasks using impedance cardiography, and (b) the influence of aging on stress responses in a multi‐ethnic pediatric sample. One hundred children 8 to 10 years old and 49 adolescents 15 to 17 years old were tested at study entry and on average 3 years later. Results showed that the composite task‐induced changes in stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR), and pre‐ejection period (PEP) were moderately stable across 3 years (rs = .36 to .51), with children showing greater stability in task‐induced CO change than did adolescents. However, the magnitude of the participant's stress responses changed over time, varied by task, age group, and gender. These results suggest that hemodynamic responses to stress change with aging during childhood and adolescence and that they can be measured reliably.
Electrophysiological insights into language processing in schizophrenia
Authors: Sitnikova Tatiana , Salisbury Dean F. , Kuperberg Gina , Holcomb Phillip J.
Published: December 2004

Deficits in language comprehension in schizophrenia were examined using event‐related potentials (ERPs). Schizophrenic and healthy participants read sentences in which the first clause ended with a homograph, and the second clause started with a target word that was semantically related to the homograph's dominant meaning (e.g., 1. Diving was forbidden from the bridge because the river had rocks in it. or 2. The guests played bridge because the river had rocks in it.). Processing of the targets (e.g., “river”) was expected to be primarily influenced by the preceding overall sentence context (congruent in 1; incongruent in 2) in healthy participants, but to be inappropriately affected by the dominant meaning of homographs (e.g., the “structure” meaning of “bridge”) in sentences like 2 in schizophrenic patients. The N400 ERP component that is known to be sensitive to contextual effects during language processing confirmed these predictions. This showed that language abnormalities in schizophrenia may be related to deficient processing of context‐irrelevant semantic representations of words from the discourse.
The art of expenditure: the court of Paola Malatesta Gonzaga in fifteenth‐century Mantua
Authors: Welch Evelyn
Published: December 2004

The paper draws on four surviving account books to examine the way a female court functioned during the first quarter of the fifteenth century. The documents, which have never received detailed attention, record Paola Malatesta Gonzaga's income and expenditure over an almost twenty‐year period, revealing her close attention to her land, estates, and the welfare of her famiglia. They also provide considerable new information for Paola's important, and now almost entirely lost, patronage of religious institutions in Mantua. From her previous historiographic role as the wife of Mantua's first marquis, Gianfrancesco Gonzaga, or as the mother of Ludovico and Cecilia Gonzaga, Paola emerges as an energetic, ambitious and culturally sensitive figure whose biography deserves re‐examination.
Dowries in fourteenth‐century Venice
Authors: Guzzetti Linda
Published: December 2004

This paper presents an analysis of two registers kept by a Venetian notary, Marino of S. Trovaso, for the years 1366–91. They preserve 1,284 records drawn up at the termination of marriages, when a court, usually the curia de proprio, returned the dowries in most cases to the widows, or otherwise to the legal heirs of the deceased wives. These records are valuable in making it possible to calculate the average value of dowries of women from all social groups, except the very poor, and the development of their values in the second half of the fourteenth century. Since the records studied constitute a relatively long series, they can be used to calculate how long marriages lasted and which spouse predeceased the other. In order to recover their dowries, Venetian widows had to prove their claims; for this purpose written evidence was preferred, but in the absence of written evidence it was possible to present witnesses to court. It is notable that almost half of these witnesses were women.
Measuring Citizen Preferences for Public Services Using Surveys: Does a “Gray Peril” Threaten Funding for Public Education?
Authors: Duncombe William , Robbins Mark , Stonecash Jeffrey
Published: December 2004

Given the rising share of senior citizens and their higher voter participation rates, seniors could represent a sizeable bloc of voters in many local elections. Concerns have been raised about a “gray peril,” where seniors vote against some local services, such as education. Preferences for education are examined using a contingent valuation survey method in the context of local school budget referenda. The results suggest for this district that elders are a heterogeneous group, and that block voting against schools is unlikely. The impact of age on preferences appears more likely to emerge in how these groups respond to changes in their economic circumstances.
Managerial Responsibility
Authors: Bertelli Anthony M. , Lynn Laurence E.
Published: December 2004

The concept of managerial responsibility is a shining thread in the literature of public administration, but its definition within our constitutional scheme remains elusive. How will we know responsible public management when we see it? We propose one answer: Public administration should be conducted according to what we term a “precept of managerial responsibility,” which involves four interrelated elements derived from the classical literature of public administration: judgment, accountability, balance, and rationality. We apply this precept to one of the most vexing problems of public administration theory and practice, institutional reform litigation. This application illustrates how the precept solves a major theoretical problem of American public administration by defining a role for administrative officers that fully comports with the Madisonian scheme of separated institutions—legislative, executive, and judicial—sharing power.
Outsourcing Regulation: Analyzing Nongovernmental Systems of Labor Standards and Monitoring
Authors: O'Rourke Dara
Published: December 2004

A range of new nongovernmental systems for advancing labor standards and enforcement have emerged over the last 5 years. This article comparatively assesses these multistakeholder systems of codes of conduct and monitoring, discusses their underlying models of regulation, and proposes a set of criteria for evaluating their effectiveness, including their legitimacy, rigor, accountability, and complementarity. Critical issues are raised about the transparency of existing initiatives, independence of monitors, convergence of standards, and dynamics among nongovernmental regulation, unions, and state enforcement. The article concludes by arguing that with increased transparency, improved technical capacities, and new mechanisms of accountability to workers and consumers, nongovernmental monitoring could complement existing state regulatory systems.
A Time for Reckoning: Jimmy Carter and the Cult of Kinfolk
Authors: Brinkley Douglas
Published: December 2004

This article focuses on former President Jimmy Carter's genealogy. It debunks the myth of the 1976 presidential campaign, chiseling away at the statue of the simple peanut farmer whose American roots took hold when a British indentured servant sold himself for transportation to the Virginia colony. Illustrated clearly is the importance of family history to Jimmy Carter. Framing the Carter family's story within the larger context of Georgia history, the author narrates its passage from Kindred Carter's first steps on Georgian soil to Jimmy Carter's wanderings through the woods surrounding his hometown.
Presidential Campaign Quality: What the Variance Implies
Authors: Buchanan Bruce
Published: December 2004

Preoccupation with presidential election results has yielded benign but regrettable neglect of other important election campaign outcomes. One important example is campaign quality, which the author defines in terms of preelection behavior that can invite or discourage two kinds of political‐system enhancing postelection results: problem‐solving energy (policy signals) and citizen allegiance (regime support). Here, the author uses measures of these concepts and resulting data to show how campaigns vary significantly in quality. Evidence from the 1988, 1992, and 1996 presidential elections suggests that variation in voter demand best accounts for differences in campaign quality.
Serving Competing Principals: The Budget Estimates of OMB and CBO in an Era of Divided Government
Authors: Engstrom Erik J. , Kernell Samuel
Published: December 2004

Battles over the federal budget have been at the heart of Washington politics over the past two decades. In assessing the potential consequences of fiscal policy choices, Congress and the president turn to the Congressional Budget Office (CBO) and the Office of Management and Budget (OMB) for spending and revenue estimates. While politicians carp about the partisanship of these agencies, previous scholarly research finds little evidence of bias. In this article, the authors systematically explore these estimates for signs of partisan bias. Specifically, the authors examine differences between OMB and CBO estimates of the president's budget since 1978 and find that agency differences are associated with party control of Congress and the presidency. During periods of divided government, when their principals may be expected to disagree most sharply about spending and taxes, these agencies' expenditure projections diverge.
Fluctuating asymmetry and immune function in a field cricket
Authors: Rantala Markus J. , Ahtiainen Jari J. , Suhonen Jukka
Published: December 2004

Recently, fluctuating asymmetry (FA) of morphological traits has attracted great attention as a short‐cut measure of individual quality. Whereas there is some evidence that FA of sexual ornaments is negatively associated with immune function, studies concerning FA and immune function in non‐ornamental traits are absent. Here, we tested whether FA of three non‐ornamental traits in hind limbs is related to male immune function in a population of the Mediterranean field cricket,Gryllus bimaculatus.As different measures of male immune function, we used encapsulation rate and lytic activity. We found that a composite measure of FA (cFA) was negatively related to encapsulation rate. However, lytic activity was not related to cFA, but there was a tendency that males with higher body mass had higher lytic activity than males with lower body mass. Our results suggest that FA in non‐ornamental traits indicates male immunocompetence inG. bimaculatus.
Use of genetic markers to quantify bumblebee foraging range and nest density
Authors: Darvill Ben , Knight Mairi E. , Goulson Dave
Published: December 2004

Bumblebees (Hymenoptera: Apidae) are important pollinators of crops and wildflowers, but many species have suffered dramatic declines in recent decades. Strategies for their conservation require knowledge of their foraging range and nesting density, both of which are poorly understood. Previous studies have mainly focussed on the cosmopolitan bumblebee species Bombus terrestris, and implicitly assume this to be representative of other species. Here we use a landscape‐scale microsatellite study to estimate the foraging range and nesting density of two ecologically dissimilar species, B. terrestris and B. pascuorum. Workers were sampled along a 10 km linear transect and 8–9 polymorphic microsatellite markers used to identify putative sisters. We provide the first published estimates of the number of colonies using a circle of radius 50 m in an agricultural landscape: 20.4 for B. terrestris and 54.7 for B. pascuorum. Estimates of nest density differed significantly between the two species: 13 km−2 for B. terrestris and 193 km−2 for B. pascuorum. Foraging ranges also differed substantially, with B. pascuorum foraging over distances less than 312 m and B. terrestris less than 625 m. Clearly bumblebee species differ greatly in fundamental aspects of their ecology. This has significant implications for the development of conservation strategies for rare bumblebees and isolated plant populations, for the management of bumblebees as pollinators, and for predicting patterns of gene flow from genetically modified plants.
Videomicroscopy of Venular Malformations (Port‐Wine Stain Type): Prediction of Response to Pulsed Dye Laser
Authors: Sevila A. , Nagore E. , Botella‐Estrada R. , Sanmartin O. , Requena C. , Serra‐Guillen C. , Guillen C.
Published: December 2004

Abstract:  Videomicroscopy has been found to be useful in determining the depth of ectasia of vascular malformations. Different patterns that hypothetically could predict the response of a vascular malformation to pulsed dye laser have been described. Our purpose was to determine if the dermoscopy pattern was able to predict the response to pulsed dye laser therapy and if it was independent of other known clinical variables. Thirty‐three consecutive children presenting for evaluation or treatment of vascular malformations underwent videomicroscopy previous to pulsed dye laser therapy. Sixty‐nine representative areas were evaluated before and after laser therapy. Other clinical factors, including location of the malformation, the patient's age and sex, and previous therapy, were also included in the analysis. We found that the dermoscopy pattern was differently distributed depending on the anatomic area. A superficial pattern was not present in the centrofacial area. An undefined pattern was most often present when a previously treated area was imaged. A superficial pattern independently predicted a good response to laser. The location of the lesion was another independent factor influencing the outcome. A new pattern consisting of a pale circular area surrounding a central brownish dot is described as negatively influencing the response to laser therapy. We concluded that videomicroscopy is a good tool for assessing which vascular malformations can be adequately treated with laser therapy, although other anatomic factors can influence the response. Videomicroscopy is particularly helpful in deciding when to end the treatment because it objectively shows when no further response can be expected, and is helpful for demonstrating this to patients and their parents.
Aquaporins account for variations in hydraulic conductance for metabolically active root regions of Agave deserti in wet, dry, and rewetted soil
Authors: NORTH G. B. , MARTRE P. , NOBEL P. S.
Published: December 2004

The importance of aquaporins for root hydraulic conductance (LP) was investigated along roots of the desert succulent Agave deserti in wet, dry and rewetted soil. Water channel activity was inferred from HgCl2‐induced reductions of LP that were reversible by 2‐mercaptoethanol. Under wet conditions, HgCl2 reduced LP for the distal root region by 50% and for the root region near the shoot base by 36% but did not affect LP for the mid‐root region. For all root regions, LP decreased by 30–60% during 10 d in drying soil and was not further reduced by HgCl2. After soil rewetting, LP increased to pre‐drying values and was again reduced by HgCl2 for the distal and the basal root regions but not the mid‐root region. For the distal region, water channels in the epidermis/exodermis made a disproportionately large contribution to radial hydraulic conductance of the intact segment; for the basal region, water channel activity was highest in the cortex and endodermis. The role of water channels was greatest in tissues in which cells were metabolically active both in the distal root region, where new apical growth occurs in wet soil, and in the basal region, which is the most likely root region to intercept light rainfall.
Properties of ion channels in the protoplasts of the Mediterranean seagrass Posidonia oceanica
Authors: CARPANETO A. , NASO A. , PAGANETTO A. , CORNARA L. , PESCE E.‐R. , GAMBALE F.
Published: December 2004

Posidonia oceanica (L) Delile, a seagrass endemic of the Mediterranean sea, provides food and shelter to marine organisms. As environment contamination and variation in physico‐chemical parameters may compromise the survival of the few Posidonia genotypes living in the Mediterranean, comprehending the molecular mechanisms controlling Posidonia growth and development is increasingly important. In the present study the properties of ion channels in P. oceanica plasma membranes studied by the patch‐clamp technique in protoplasts obtained from the young non‐photosynthetic leaves were investigated. In protoplasts that were presumably originated from sheath cells surrounding the vascular bundles of the leaves, an outward‐rectifying time‐dependent channel with a single channel conductance of 58 ± 2 pS which did not inactivate, was selective for potassium and impermeable to monovalent cations such as Na+, Li+ and Cs+ was identified. In the same protoplasts, an inward‐rectifying channel that has a time‐dependent component with single channel conductance of the order of 10 pS, a marked selectivity for potassium and no permeation to sodium was also identified, as was a third type of channel that did not display any ionic selectivity and was reversibly inhibited by tetraethylammonium and lanthanum. A comparison of Posidonia channel characteristics with channels identified in terrestrial plants and other halophytic plants is included.
Does turgor limit growth in tall trees?
Authors: WOODRUFF D. R. , BOND B. J. , MEINZER F. C.
Published: December 2004

The gravitational component of water potential contributes a standing 0.01 MPa m−1to the xylem tension gradient in plants. In tall trees, this contribution can significantly reduce the water potential near the tree tops. The turgor of cells in buds and leaves is expected to decrease in direct proportion with leaf water potential along a height gradient unless osmotic adjustment occurs. The pressure–volume technique was used to characterize height‐dependent variation in leaf tissue water relations and shoot growth characteristics in young and old Douglas‐fir trees to determine the extent to which growth limitation with increasing height may be linked to the influence of the gravitational water potential gradient on leaf turgor. Values of leaf water potential (Ψl), bulk osmotic potential at full and zero turgor, and other key tissue water relations characteristics were estimated on foliage obtained at 13.5 m near the tops of young (approximately 25‐year‐old) trees and at 34.7, 44.2 and 55.6 m in the crowns of old‐growth (approximately 450‐year‐old) trees during portions of three consecutive growing seasons. The sampling periods coincided with bud swelling, expansion and maturation of new foliage. Vertical gradients ofΨland pressure–volume analyses indicated that turgor decreased with increasing height, particularly during the late spring when vegetative buds began to swell. Vertical trends in branch elongation, leaf dimensions and leaf mass per area were consistent with increasing turgor limitation on shoot growth with increasing height. During the late spring (May), no osmotic adjustment to compensate for the gravitational gradient ofΨlwas observed. By July, osmotic adjustment had occurred, but it was not sufficient to fully compensate for the vertical gradient ofΨl. In tall trees, the gravitational component ofΨlis superimposed on phenologically driven changes in leaf water relations characteristics, imposing potential constraints on turgor that may be indistinguishable from those associated with soil water deficits.
Isoprenoid emission in trees of Quercus pubescens and Quercus ilex with lifetime exposure to naturally high CO2 environment†
Authors: RAPPARINI F. , BARALDI R. , MIGLIETTA F. , LORETO F.
Published: December 2004

The long‐term effect of elevated atmospheric CO2 on isoprenoid emissions from adult trees of two Mediterranean oak species (the monoterpene‐emitting Quercus ilex L. and the isoprene‐emitting Quercus pubescens Willd.) native to a high‐CO2 environment was investigated. During two consecutive years, isoprenoid emission was monitored both at branch level, measuring the actual emissions under natural conditions, and at leaf level, measuring the basal emissions under the standard conditions of 30 °C and at light intensity of 1000 µmol m−2 s−1. Long‐term exposure to high atmospheric levels of CO2 did not significantly affect the actual isoprenoid emissions. However, when leaves of plants grown in the control site were exposed for a short period to an elevated CO2 level by rapidly switching the CO2 concentration in the gas‐exchange cuvette, both isoprene and monoterpene basal emissions were clearly inhibited. These results generally confirm the inhibitory effect of elevated CO2 on isoprenoid emission. The absence of a CO2 effect on actual emissions might indicate higher leaf temperature at elevated CO2, or an interaction with multiple stresses some of which (e.g. recurrent droughts) may compensate for the CO2 effect in Mediterranean ecosystems. Under elevated CO2, isoprene emission by Q. pubescens was also uncoupled from the previous day's air temperature. In addition, pronounced daily and seasonal variations of basal emission were observed under elevated CO2 underlining that correction factors may be necessary to improve the realistic estimation of isoprene emissions with empirical algorithms in the future. A positive linear correlation of isoprenoid emission with the photosynthetic electron transport and in particular with its calculated fraction used for isoprenoid synthesis was found. The slope of this relationship was different for isoprene and monoterpenes, but did not change when plants were grown in either ambient or elevated CO2. This suggests that physiological algorithms may usefully predict isoprenoid emission also under rising CO2 levels.