Influence of different heat stress models on nutrient digestibility and markers of stress, inflammation, lipid, and protein metabolism in broilers

This experiment determined the effects of different HS models and pair-feeding (PF) on nutrient digestibility and markers of stress, inflammation, and metabolism in broilers. Birds (720 total) were allocated into 12 environmentally controlled chambers and reared under thermoneutral conditions until 20 d. Until 41 d birds were exposed to 4 treatments, including: thermoneutral at 24°C (TN-al), daily cyclic HS (12 h at 24 and 12 h at 35°C; cyHS), constant HS at 35°C (coHS), and PF birds maintained at 24°C and fed to equalize FI with coHS birds (TN-coPF). At d 41, ileal digesta were collected to determine nutrient apparent ileal digestibility (AID). Blood, liver, and breast tissues were collected from 8 birds per treatment to determine the mRNA expression of stress, inflammation, and metabolism markers. An additional 8 TN-al birds were sampled after acute HS exposure at 35°C for 4 h (aHS), and 8 cyHS birds were sampled either right before or 4 h after HS initiation. Data were analyzed by 1-way ANOVA and means were separated using Tukey's HSD test. Compared with TN-al birds, AID of nitrogen and ether extract were reduced in coHS birds, and both cyHS and coHS reduced (P < 0.05) AID of total essential amino acids. TNFα and SOD2 expression were increased (P < 0.05) under aHS, coHS, and TN-coPF conditions. IL6 and HSP70 were increased (P < 0.05) under coHS and aHS, respectively. Expression of lipogenic enzymes ACCα and FASN were reduced by coHS and TN-coPF, while coHS increased the lipolytic enzyme ATGL (P < 0.05). IGF1 was lowered in coHS birds, and p70S6K and MyoG were reduced under coHS and TN-coPF (P < 0.05). Interestingly, MuRF1 and MAFbx were increased (P < 0.05) under coHS only. Overall, these results indicate that coHS has a greater impact on nutrient digestibility and metabolism than aHS and cyHS. Interestingly, increased protein degradation during HS appears to be mostly driven by HS per se and not the reduced FI.

129 RE-THINKING THE MEMORY CONSENSUS MEETING: A QUALITY IMPROVEMENT INITIATIVE

Background

As part of our memory clinic service, weekly consensus meetings are held to allow for multidisciplinary diagnostic evaluation of new cases. As part of a local Quality Improvement (QI) initiative, we reviewed how this meeting could be streamlined to maximise efficiency and improve diagnostic accuracy in light of increasing referrals and patient complexity. Here we describe the development and initial implementation of this QI project.

Methods

A structured QI approach was taken to develop SMART (Specific, Measurable, Achievable, Realistic, Timely) goals. All professional stakeholders (from disciplines including geriatric medicine, neurology and psychiatry of later life) who attend the weekly consensus meeting were surveyed anonymously with a response rate of 80% (n=8). Information was gathered on areas that worked well, areas that needed improvement and suggestions for meeting enhancement. In addition, participants were asked at a single meeting to subjectively rate the complexity of eleven cases presented into the following categories: low, medium and high. Data were collated and presented to the memory clinic staff for further refinement.

Results

Four key actions were identified for implementation: formal allocation of a meeting chair, improvement of access to imaging from outside hospitals, revision of current proforma to streamline case discussions, and proposal to discuss patients in order of new assessment, return assessment and review of significant results. During the rating of case complexity, there was substantial variation among respondents.

Conclusion

This initial phase has been used to develop SMART goals to improve the consensus meeting structure. We identified that patient complexity would be an inefficient method to order case discussion. Implementation of action steps are ongoing, with positive feedback from staff to date.

Factors associated with liking of milk among preschool children

Background

Adequate calcium intake in childhood is essential for bone health, and dairy products are an important dietary source. However, children's milk consumption has reduced over the past decade in developing countries. Food preferences are a key determinant of consumption, and those developed in early life can persist into adulthood. Therefore, promoting a liking for milk before school age may be effective in improving milk consumption further into childhood. The aim of this analysis is to explore the factors associated with liking of milk among preschool children.

Methods

Questionnaires were completed by parents of 2-5 year-old children as part of a pilot intervention aiming to increase milk consumption in 12 preschools. Chi-squares and hierarchial logistic regression were used to examine the association between children's liking of milk, as reported by parents, and child-related factors (infant feeding; demographics; diet) and parent-related factors (attitudes; milk consumption and liking; education).

Results

Responses from 319 parents of 2-5 year-old children (50.5% male, 49.5% female) were analysed. Ninety-two percent of respondents were mothers and 85% of parents reported that their children liked the taste of milk. In a logistic regression model (N = 281) parents' belief that it is difficult to encourage their child to drink milk was associated with a lower likelihood of children liking the taste of milk (OR = 0.028; CI = 0.011, 0.075; P &lt; 0.001). Liking of milk was not significantly associated with other factors examined (P &lt; 0.05).

Conclusions

The present analysis suggests that parents' self-efficacy in encouraging their child to drink milk may be important in influencing their child's liking of its taste, and should be considered in interventions aiming to improve milk consumption. The taste of milk was well-liked in this cohort of preschool children and therefore, further research is necessary in a cohort with varying levels of milk consumption and liking of milk.

Key messages

Parental beliefs should be included as intervention targets when aiming to improve a liking for milk among preschool children. Further research on the determinants of milk consumption and liking of milk is necessary in diverse cohorts of preschool children.

Shifting the HIV Paradigm from Care to Cure: Proceedings from the Caribbean Expert Summit in Barbados, August 2017

The CCAS EXPERT SUMMIT convened an array of international experts in Barbados on August 27-31, 2017 under the theme "From Care to Cure-Shifting the HIV Paradigm." The Caribbean Cytometry & Analytical Society (CCAS) partnered with the Joint United Nations Programme on HIV/AIDS (UNAIDS) to deliver a program that reviewed the advances in antiretroviral therapy and the public health benefits accruing from treatment as prevention. Particular emphasis was placed on reexamining stigma and discrimination through a critical appraisal of whether public health messaging and advocacy had kept pace with the advances in medicine. Persistent fear of HIV driving discriminatory behavior was widely reported in different regions and sectors, including the healthcare profession itself; continued fear of the disease was starkly misaligned with the successes of new medical treatments and progress toward the UNAIDS 90-90-90 targets. The summit therefore adopted the mantra "Test-Treat-Defeat" to help engage with the public in a spirit of optimism aimed at creating a more conducive environment for persons to be tested and treated and, thereby, help reduce HIV disease and stigma at the individual and community levels.

A Study To Assess The Prevalence Of Exercise-Induced Bronchoconstriction In Inter-County Hurling

Exercise-Induced Bronchoconstriction (EIB) is an acute, transient airway narrowing occurring after exercise which may impact athletic performance. Studies report 10% of the general population and up to 90% of asthmatics experience EIB. Ninety-two players from three elite hurling squads underwent a spirometric field-based provocation test with real-time heart rate monitoring and lactate measurements to ensure adequate exertion. Players with a new diagnosis of EIB and those with a negative field-test but with a previous label of EIB or asthma underwent further reversibility testing and if negative, methacholine challenge. Eight (8.7%) of players had EIB, with one further athlete having asthma with a negative field test. Interestingly, only three out of 12 players who had previously been physician-labelled with EIB or asthma had their diagnosis objectively confirmed. Our study highlights the role of objective testing in EIB.

Surface wetting strategy prevents acute heat exposure-induced alterations of hypothalamic stress- and metabolic-related genes in broiler chickens

Heat stress (HS) is devastating to poultry production worldwide, yet its biology and molecular responses are not well defined. Although advances in management strategy have partially alleviated the negative impact of HS, productivity still continues to decline when the ambient temperature rises. Therefore, identifying mechanism-based approaches to decrease HS susceptibility while improving production traits is critical. Recently, we made a breakthrough by applying a surface wetting strategy and showing that it improves growth performance compared with the current conventional cooling system. In the present study, we aimed to further define molecular mechanisms associated with surface wetting in ameliorating HS productivity loss in broilers. Five-week-old broiler chickens were exposed to acute HS (35°C for 2 h) alone or in combination with surface wetting. A control group was maintained at thermoneutral conditions (25°C). Core body temperature (BT) and feed intake were recorded. Blood was collected and hypothalamic tissues (main site involved in the regulation of energy homeostasis) were harvested to determine the expression profile of stress- and metabolic-related genes. Surface wetting prevents HS from increasing BT and plasma corticosterone levels ( < 0.05) and improves feeding and drinking behaviors. At molecular levels, surface wetting blocks the activation of hypothalamic heat shock protein and adenosine monophosphate-activated protein-induced by HS and significantly modulates the expression of feeding-related hypothalamic neuropeptides (agouti-related protein, proopiomelanocortin, orexin, orexin receptor, and leptin receptor). Taken together, our data represent the first evidence that surface wetting alleviates systemic and intracellular stress induced by HS and preserves the intracellular energy status, which, in turn, may result in improved broiler well-being and growth performance.

Cognitive screening in the acute hospital: Preliminary findings from a cognitive screening program in a university-affiliated, tertiary-referral hospital with 6-month interval outcomes

Introduction

Cognitive impairment impacts on patient outcomes [1] but is under-recognised in acute hospitals [2]. Data on rates and degree of impairment among hospital inpatients remain sparse. This information is vital for strategic planning of health services as the European population ages.

Objectives

To examine the rates and degree of cognitive impairment among patients aged 65 and older who were admitted to an acute general hospital and to assess its impact on patient outcomes.

Methods

All patients aged over 65 who were admitted over a 2-week period were invited to participate. Those who met the inclusion criteria were screened for delirium then underwent a cognitive screening battery. Normative values for age and level of education were obtained from the TILDA study [3]. Demographic and outcome data were obtained from medical records.

Results

One hundred and forty-eight patients underwent cognitive screening. Thirty-nine over 148 (26%) met the DSM-IV criteria for dementia of whom only 16 (41%) had a previously-documented impairment. Thirty over 148 (20%) had evidence of cognitive impairment that did not meet criteria for dementia, only 3 (10%) of whom were previously documented. Seventy-three over 148 (49%) were normal. Six over 148 (4%) were not classifiable. The impact of cognitive status on length of hospital stay, number of readmissions in 6 months and discharge destination was investigated. Impact on length of stay was significant (P = 0.017) but significance was not achieved against number of readmissions or discharge destination.

Conclusions

Cognitive impairment is pervasive and under-recognised in the acute hospital and impacts on length of hospital stay. Longer interval analysis is necessary to investigate further implications.

References 1–3 available upon request.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Expression profile of hypothalamic neuropeptides in chicken lines selected for high or low residual feed intake

The R(+) and R(-) chicken lines have been divergently selected for high (R(+)) or low (R(-)) residual feed intake. For the same body weight and egg production, the R(+) chickens consume 40% more food than their counterparts R(-) lines. In the present study we sought to determine the hypothalamic expression profile of feeding-related neuropeptides in these lines maintained under fed or food-deprived conditions. In the fed condition, the suppressor of cytokine signaling 3 (SOCS3) was 17-fold lower (P<0.05) and the ghrelin receptor was 7-fold higher (P<0.05) in R(+) compared to R(-) chicken lines. The hypothalamic expression of the other studied genes remained unchanged between the two lines. In the fasted state, orexigenic neuropeptide Y and agouti-related peptide were more responsive, with higher significant levels in the R(+) compared to R(-) chickens, while no significant differences were seen for the anorexigenic neuropeptides pro-opiomelanocortin and corticotropin releasing hormone. Interestingly, C-reactive protein, adiponectin receptor 1 and ghrelin receptor gene expression were significantly higher (12-, 2- and 3-folds, respectively), however ghrelin and melanocortin 5 receptor mRNA levels were lower (4- and 2-folds, P=0.05 and P=0.03, respectively) in R(+) compared to R(-) animals. We identified several key feeding-related genes that are differently expressed in the hypothalamus of R(+) and R(-) chickens and that might explain the difference in feed intake observed between the two lines.

Raising the priority of chronic noncommunicable diseases in the Caribbean

The Caribbean's long history of cooperation in health now focuses on noncommunicable diseases (NCDs), given that Caribbean Community (CARICOM) countries have the highest NCD burden in the Americas. The heads of government convened a first in the world one-day summit on NCDs, largely due to advocacy by George Alleyne and others, on the health, social, and economic impact of NCDs; the need for upstream multisectoral interventions to address the common, multifactoral risks; and the need for increased global attention to NCDs. Implementation of the NCD Summit Declaration mandates was most effective in larger countries with greater capacity, but countries of all sizes performed well, when they had regional or global support. Progress was limited in regional approaches to food security, labeling, and elimination of trans fats. Inadequate funding stymied several resource-dependent interventions. Monitoring mechanisms were established, but more concrete goals are needed, especially for actions of nonhealth government agencies.

Esca Studies of the Valence band and Loss Spectra of Semiconductor Films: Ionicity and Chemical Bonding

ESCA valence band and core level loss results have been determined that appear to be directly related to the degree of covalency/ionicity and other bonding features of certain semi-conductor systems. Specific applications are presented that aid in the characterization of the key chemistry of dielectric oxide/semiconductor interfaces and also may help to determine the relative metastability of the solid solution of Group IV elements (e.g., Ge) into certain III-V lattices (e.g., GaAs). It is shown that these features are not detectable through conventional core level shift arguments, and that the aforementioned novel approaches often require high resolution ESCA.

A tephritid fly mimics the territorial displays of its jumping spider predators

The tephritid fly Zonosemata vittigera (Coquillett) has a leg-like pattern on its wings and a wing-waving display that together mimic the agonistic territorial displays of jumping spiders (Salticidae). Zonosemata flies initiate this display when stalked by jumping spiders, causing the spiders to display back and retreat. Wing transplant experiments showed that both the wing pattern and wing-waving displays are necessary for effective mimicry: Zonosemata flies with transplanted house fly wings and house flies with transplanted Zonosemata wings were attacked by jumping spiders. Similar experiments showed that this mimicry does not protect Zonosemata against nonsalticid predators. This is a novel form of sign stimulus mimicry that may occur more generally.

Twenty-four hour hypothermic machine perfusion preservation of porcine pancreas facilitates processing for islet isolation

Procurement of donor pancreata for islet isolation and transplantation is not yet widely practiced due to concerns about the impact of postmortem ischemia on functional islet yields. Perfusion/preservation technology may help to circumvent ischemic injury as applied in this study of porcine pancreata prior to islet isolation. Pancreata harvested from adult pigs were assigned to 1 of 3 preservation treatment groups: G1, fresh controls, processed immediately with minimum cold ischemia (<1 hour); G2, static cold storage, flushed with cold UW-Viaspan and stored at 2 degrees -4 degrees C for 24 hours; and G3, hypothermic machine perfusion (HMP) on a pulsatile LifePort machine Organ Recovery Systems, Inc., Des Plaines, Ill, United States with KPS1 solution at 4-7 degrees C and low pressure (10 mm Hg) for 24 hours. Islet isolation was then accomplished using conventional methods. Product release criteria were used to assess islet yield and function. Islet yield was markedly different between the treatment groups. There was a statistically significant increased yield in the HMP group over static cold storage in UW-Viaspan (P < .05). Functionally, the islets from each experimental group were equivalent and not significantly different from fresh controls (G1). Dithizone staining of islets showed consistently more uniform digestion of pancreata from G3 compared with G1 and G2, with greater separation of the tissue and fewer entrapped islets. HMP for 24 hours was well tolerated, leading to moderate edema but no loss of function of the harvested islets. The edema appeared to aid in enzymatic digestion, producing a greater yield and purity of islets compared with pancreata subjected to 24 hours of static cold storage.

Transcription defects induced by repeat expansion: fragile X syndrome, FRAXE mental retardation, progressive myoclonus epilepsy type 1, and Friedreich ataxia

Fragile X mental retardation syndrome, FRAXE mental retardation, Progressive myoclonus epilepsy Type I, and Friedreich ataxia are members of a larger group of genetic disorders known as the Repeat Expansion Diseases. Unlike other members of this group, these four disorders all result from a primary defect in the initiation or elongation of transcription. In this review, we discuss current models for the relationship between the expanded repeat and the disease symptoms.

Idiosyncratic profiles of collinearity error using segments and dot pairs

It is well known that judgments of oblique line segments are more variable and less accurate than are judgments of horizontal or vertical segments, i.e., the "oblique effect." A prior study from our laboratories confirmed these differentials for a task in which the collinearity of segments at various angular positions was judged. Further, that study found that each observer manifests a distinct, idiosyncratic profile of errors across the 360 degrees range. These error tendencies are conspicuous in models derived by harmonic analysis, and we describe significant excursions of a given model as "delta errors." The present experiments found complex profiles of delta error with various stimulus and test conditions. A given subject manifested similar models of delta error when judging collinearity of dot pairs versus line segments. In the prior work the segments to be judged were asymmetrically positioned upon the test sheet. However, the asymmetric positioning is not responsible for the errors, as the present work found errors excursions with a round display field. Similar profiles of delta error were found when subjects were allowed to mark an open space, versus being required to respond at a specific distance (indicated by a target circle). This addresses questions of whether the error should be measured as an angle. In the two final experiments, we present evidence that the source of delta error within the nervous system is at the point of binocular synthesis of the information from the two eyes, or beyond, and the effects are not due to errors of reaching. Potential neural substrates for these complex, idiosyncratic error tendencies are discussed.

Recurrent falls are associated with increased length of stay in elderly psychiatric inpatients

OBJECTIVES

To identify factors which may contribute to prolonged length of stay in an elderly psychiatric inpatient setting.

DESIGN

Retrospective case note study.

METHODS

A list of all patients over the age of 65 discharged from a private psychiatric hospital over a three-year period excluding those with a length of stay of over 365 days was obtained (n = 1147). A random sample of 150 patients was selected from the study population. A case note study was then performed looking at a number of variables which have been postulated to affect length of stay. The resulting data was analysed using multivariate statistics.

RESULTS

There was no statistically significant association found between baseline factors (including age, gender, cognitive impairment, marital status, order of admission and preadmission living arrangement) and length of stay. Having recurrent falls whilst an inpatient was associated with prolonged hospital stay (p = 0.0006).

CONCLUSION

Experiencing recurrent falls whilst an inpatient is associated with prolonged length of stay. Recurrent falls in the elderly may be associated with both physical illness and the use of psychotropic medications. A prospective study examining factors contributing to falls would be important in decreasing fall risk and reducing length of stay.

Verbal aggression in Alzheimer's disease. Clinical, functional and neuropsychological correlates

OBJECTIVES

To determine the clinical, functional and neuropsychological correlates of verbal aggression in Alzheimer's disease in a group of consecutive first attendees to a memory clinic.

METHODS

150 people were evaluated and diagnosed as suffering with probable Alzheimer's disease. These people were tested using the Behave-AD for the presence of verbal aggression, delusions, depression and agitation. They were also assessed with cognitive, functional and neuropsychological scales.

RESULTS

Twenty-eight per cent of this group of Alzheimer patients had exhibited some verbal aggression in the preceding month. Male gender (p = 0.022), the presence of paranoid and delusional ideation (p = 0.003) and agitation (p = 0.042) were significantly associated with verbal aggression in a stepwise backward logistic regression analysis.

CONCLUSION

The presence of verbal aggression should prompt the clinician to search for delusional ideation, which may respond to pharmacotherapy.

Evaluating models of collinearity judgment for reliability and scale

In prior work from this laboratory, we have examined how accurately subjects can judge collinearity, i.e. alignment, as a function of the angular position of stimulus elements. In those experiments, subjects were presented with a line segment (or a pair of dots) which varied across the 360 degrees range of angular positions, and were required to select and mark a point which was perceived as being collinear. We found that the models of error for each subject consisted of a complex set of peaks and valleys which are herein described as delta excursions. The error tendencies appeared to be idiosyncratic, in that each subject manifested a different profile of these excursions. Here we report the results of three experiments. In the first, we tested subjects across five sessions, and found that the five models of error were fairly comparable for a given subject. In the second and third experiments, we tested at close intervals of angular position, and found evidence for localized sources of error. We continue to find that the error model for each subject is idiosyncratic, and argue that the excursions may be due to defects in a system which combines responses from position-encoding fields that vary in size.

Further consideration of size illusions in random dot stereograms

It has been suggested that many geometric illusions are caused by the application of depth or size constancy rules to an image which does not have sufficient cues to establish that the elements lie in a flat plane. Thus, converging lines are taken as depth cues, and the attributed depth provides the basis for adjusting the perceived size of stimulus elements. It this is the case, one should not see a distortion of relative size if the disparity cues provide for strong statification, i.e., localization in depth of the linear perspective cues. This expectation is challenged by demonstrations that show distortions of relative size using random-dot stereograms. In 1971 Julesz provided such examples but did not comment on the implications for theories of depth. Here we redemonstrate these distortion of length and size in autostereograms which contain the Ponzo and Corridor configurations. The illusory distortions can be seen in the cyclopean view even though the linear perspective elements are well stratified. We suggest that the processing of binocular disparity cues, as required for judgments of absolute distance, may involve the dorsal stream of vision, i.e., activity passing into and including the parietal lobe. Pictorial cues, on the other hand, are likely passed through the ventral stream into the temporal lobe. The analysis of depth by this system provides for size constancy and, possibly, the calibration of relative motion.

The effects of limiting punitive damage awards

In response to concerns that jury awards in tort cases are excessive and unpredictable, nearly every state legislature has enacted some version of tort reform that is intended to curb extravagant damage awards. One of the most important and controversial reforms involves capping (or limiting) the maximum punitive damage award. We conducted a jury analogue study to assess the impact of this reform. In particular, we examined the possibility that capping punitive awards would cause jurors to inflate their compensatory awards to satisfy their desires to punish the defendant, particularly in situations where the defendant's conduct was highly reprehensible. Relative to a condition in which punitive damages were unlimited, caps on punitive damages did not result in inflation of compensatory awards. However, jurors who had no option to award punitive damages assessed compensatory damages at a significantly higher level than did jurors who had the opportunity to do so. We discuss the policy implications of these findings.

The effects of defendant conduct on jury damage awards

Laws of negligence dictate that jurors' decisions about damages be influenced by the severity of plaintiffs' injuries and not by the reprehensibility of defendants' conduct. The authors simulated an automobile negligence trial to assess whether jurors' decisions are in accord with those expectations. Conduct of the defendant and severity of the plaintiff's injuries were manipulated. Jurors listened to the evidence, completed predeliberation questionnaires, deliberated as a jury, and completed postdeliberation questionnaires. Severity of the plaintiff's injury had a strong impact on damage awards, but evidence related to the defendant's conduct was also influential, particularly when the plaintiffs injuries were mild. Here, jurors with any conduct-related evidence gave larger damage awards than jurors with no conduct-related evidence. Findings suggest an effect of defendant conduct on damage awards that may be mediated by judgments that the defendant was negligent.

Disruptive sexual selection for plumage coloration in a passerine bird

The theory of sexual selection was developed to explain the evolution of highly exaggerated sexual ornaments. Now supported by vast empirical evidence, sexual selection is generally considered to favour individuals with the most extreme trait expression. Here we describe disruptive selection on a sexual ornament, plumage coloration, in yearling male lazuli buntings (Passerina amoena). In habitats with limited good-quality nesting cover, the dullest and the brightest yearlings were more successful in obtaining high-quality territories, pairing with females and siring offspring, than yearlings with intermediate plumage. This pattern reflects the way that territorial adult males vary levels of aggression to influence the structure of their social neighbourhood. Adult males showed less aggression towards dull yearlings than intermediate and bright ones, permitting the dull yearlings to settle on good territories nearby. Fitness comparisons based on paternity analyses showed that both the adults and dull yearlings benefited genetically from this arrangement, revealing a rare example of sexually selected male-male cooperation.

Individual differences in collinearity judgment as a function of angular position

Previous research indicates that perceived orientation and/or alignment of segments and points can vary as a function of the angular position of the stimulus elements. Several studies show that the variability of the responses is least and accuracy of judgment is greatest where segments and dots are aligned with a cardinal axis. Additionally, some report assimilation of judgments toward the nearest cardinal axis--that is, the segments (or dots) are seen as being closer to the horizontal or vertical than is true. The present research confirms that judgments of collinearity are least variable and most accurate when the segment being judged is aligned with a cardinal axis. However, we do not find any consistent tendency for cardinal axis assimilation. Plotting the collinearity error (delta) as a function of angular position (phi), we find a distinctive profile of oscillation for each subject. Furthermore, subjects who were evaluated in two sessions showed very similar profiles of delta oscillation from Day 1 to Day 2. Harmonic analysis indicated a wide-ranging pattern of significant components. The components at the 4th harmonic and below were more likely to be significant, but each subject showed differential loadings in terms of which of the components were significant, as well as in the sign and amplitude of significant components. These results may reflect idiosyncratic fixation tendencies, or individual differences in the design of neural mechanisms that encode the angular positions of stimuli.

Compensating plaintiffs and punishing defendants: is bifurcation necessary?

Critics of the civil jury have proposed several procedural reforms to address the concern that damage awards are capricious and unpredictable. One such reform is the bifurcation or separation of various phases of a trial that involves multiple claims for damages. The purpose of this study was to assess the effects of bifurcating the compensatory and punitive damages phases of a civil tort trial. We manipulated the wealth of the defendant and the reprehensibility of the defendant's conduct (both sets of evidence theoretically related to punitive but not to compensatory damages) across three cases in a jury analog study. We wondered whether jurors would misuse the punitive damages evidence in fixing compensatory damages and whether bifurcation would effectively undo this practice. Our findings indicated that mock jurors did not improperly consider punitive damages evidence in their decisions about compensation. Moreover, bifurcation had the unexpected effect of augmenting punitive damage awards. These findings raise questions about the merits of bifurcation in cases that involve multiple claims for damages.

A test of the gravity lens theory

Naito and Cole [1994, in Contributions to Mathematical Psychology: Psychometrics and Methodology Eds G H Fischer and D Laming (New York: Springer)] provide a configuration which they describe as the Gravity Lens illusion. In this configuration, four small dots are presented in proximity to four large disks, and one is asked to compare the slope of an imaginary line which connects one pair of dots with the slope of a line which connects the other pair. In fact the slopes are the same, i.e. their axes are parallel, but because of the positioning of the large disks they appear to be at different orientations. Naito and Cole propose that the perceptual bias is analogous to the effects of gravity on the metrics of physical space, such that mental projections in the vicinity of a disk (or an open circle) are distorted just as the path of light is bent as it passes a massive body such as a star. Here we provide a simple test of this concept by having subjects judge alignments of dots which lie near tangents to a circle. Subjects were asked to project straight lines through pairs of stimulus dots, selecting and marking points in open space which were collinear with each pair. As would be predicted by the Gravity Lens theory, the locations selected by subjects were displaced from straight lines. However, the error magnitudes were substantially larger for judgments of dot pairs which had an oblique alignment, as compared with dot pairs which were aligned with a cardinal axis. This differential of effect as a function of stimulus orientation is not predicted by the gravity concept.

Health promotion and education in youth correctional facilities

In 1997 a comprehensive perinatal/pediatric needs assessment was conducted in the two counties comprising the region. As a result, the Regional Perinatal Consortium of Monmouth and Ocean Counties, Inc. submitted both a perinatal and a pediatric plan that addressed the strengths and the needs of the region to the New Jersey Department of Health and Senior Services. One of thirteen pediatric action plans, Pediatric Health Care and Educational Services in Correctional Facilities, set the stage for the start of ongoing and wide-ranging health programs for the youth in one of the county youth detention centers. Beginning with "Alternatives to Violence," Consortium staff have met monthly with the incarcerated youth to plan and provide these much needed sessions. As expected, these sessions have produced many responses from the youth, some anticipated and many pleasantly surprising, as they have begun to recognize the helpful intent and nature of our programs. The youth are encouraged to participate in planning for upcoming programs and their input is appreciated and respected. As many of these teens are parents themselves, this program has also been able to incorporate parenting skills in some of the sessions, with a major focus on child abuse prevention. Health-education services for incarcerated youth open the door to an exciting frontier for pediatric nurses to deliver prevention in this much-needed setting. This program is a model for planning, implementing, and evaluating public health programs in the pediatric arena.

Similar Müller-Lyer effects from operant and comparison response modes

A one-sided (monopole) version of the Müller-Lyer was used to assess the effect of response mode on the metric distortion associated with the illusion. Two different response modes were tested for comparability. The Operant Mode required the judgment of stimulus span to be indicated by marking a dot on the test page. The Comparison Mode required judgment of equality of two adjoining prepositioned spans. The perceptual effects with the comparison procedure are known to consist of underestimation of spans which are bounded by concave fin-sets and over-estimation of spans which are bounded by convex fin-sets. The question is whether the motor demands of the operant task produce an additional source of metric bias. Analysis indicate a very high correlation of judgments for the two modes of testing. Also, data with either mode of responding closely fit a linear model of the effect, and the model provides comparable index values for the concave and convex versions. These results should mitigate concern about potential motor bias from the operant method and encourage its use as a more efficient procedure for assessing metric distortion.

Red squirrels, Tamiasciurus hudsonicus, produce predator-class specific alarm calls

Red squirrels, can produce alarm calls when they detect a potential predator. Observations of natural interactions between red squirrels and large birds, and predator-presentation experiments in the field, showed that red squirrels produce acoustically different alarm calls in response to aerial danger (live birds and a model hawk flown towards them) versus danger approaching from the ground (dogs and humans). The alarm call produced in response to aerial danger is acoustically convergent on the 'seet' alarm call produced by many species of passerine birds in response to raptors. The squirrels' 'seet' alarm is a short, low-amplitude, high-frequency call. These characteristics make the call difficult to localize, and is in a frequency range that is poorly perceived by raptors. Red squirrels produce much louder, wide-bandwidth bark calls in response to terrestrial danger. This is the first demonstration of predator-class specific alarm calls of red squirrels. Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.

Evaluating the decay gradient for collinearity bias with lateral displacement from the axis of induction

The misperception of alignment which is found in many geometric illusions can be quantified using relatively simple stimulus configurations. Perceived collinearity of one segment (designated as the test segment) is biased by a second segment (designated as the induction segment), with the size of effect being a function of the relative angle between the two segments. The process can be described as angular induction. The strength of bias is greatest when the induction segment is centered at the tip of the test segment. Tong and Weintraub have reported that lateral displacement from the tip, i.e., at right angles to the axis of the induction segment, produces a sharp drop in the strength of effect. This decline is described as a "decay gradient" for the angular induction. One experiment replicates and provides better quantification of this "decay gradient". Two other experiments examine the decay gradient using a pair of induction segments, one on each side of the tip of the test segment. Displacement of the segments (either in the same direction or in opposite directions) produces substantially the same gradient of effect. Therefore, previous evidence of "tandem boosting" of effect for segment pairs does not depend on collinearity among the stimulus components. Finally, a fourth experiment finds that an induction segment which is at a fixed position and orientation differentially affects the influence of a variable induction segment. At some angles the influence of the variable segment is augmented, and at others it is suppressed. These findings are discussed in a neuroreductionist context, and a simple model for angular induction is presented.

Evaluating Müller-Lyer effects using single fin-set configurations

Four experiments were conducted to study the bias of perceived length for Müller-Lyer configurations that contained a single set of fins (i.e., two segments that join to form a vertex). The experiments manipulated several factors that have been shown to be critical to the effect: (1) version (which way the apex pointed), (2) length of the stimulus span, (3) presence or absence of a line segment in the span being judged, (4) fin length, (5) fin angle, and (6) the zone in which the response was rendered. Using percent error as the index of perceptual distortion, the major finding was that the two versions show an opposite slope for strength of effect as a function of span. When stimulus spans were plotted against response means (not converting to percent error), an almost perfect linear relation was found. These results indicate that the perceptual effects can be modeled as a linear system having two parameters through which the treatments exert their influence. The results are discussed in relation to major theories of mechanism for the Müller-Lyer illusion.

Synaptic membrane G proteins are complexed with tubulin in situ

The G proteins G S and Gi1 appear to be capable of binding to tubulin specifically, and it has been suggested that such binding results in G protein activation via direct transfer of GTP. This study was undertaken to demonstrate that consequences of G protein activation by tubulin, i.e., stimulation or inhibition of adenyl cyclase, were dependent on the G proteins expressed as well as unique aspects of the membrane or cytoskeleton in a given cell type. Membranes from rat C6 glioma cells, which express G s alpha but not G i alpha 1, responded to the addition of tubulin with a stable activation of adenyl cyclase. Conversely, membranes from rat cerebral cortex, which contain both G s and G i 1, responded to exogenous tubulin with a stable inhibition of adenyl cyclase. Unlike C6 membranes, cerebral cortex membranes are richly endowed with tubulin, and antitubulin antibodies immunoprecipitated complexes of tubulin and G i 1 and G s from detergent extracts of these membranes. Nearly 90% of the G s alpha from Triton X-114 extracts coimmunoprecipitated with tubulin, suggesting that these proteins exist as a complex in the synaptic membrane. Such complexes may provide the framework for a G protein-cytoskeleton link that participates in the modulation of cellular signal transduction.

Probing collinearity bias in the close induction field

The substrates of the Poggendorff illusion can be evaluated using as few as two line segments, a test segment whose collinearity is judged, and an induction segment which serves to bias that judgment. Previous research from this laboratory has shown that a very short induction segment can produce a substantial bias of perceived collinearity when it is centered at the tip of the test segment, and there is some evidence that the symmetry of this configuration affects the strength of this bias. Four experiments were conducted to clarify the issue of symmetry in the stimulation of the "half-field" zones which lie on each side of the tip. That Exp. 1a showed displacements which moved the induction segment to an eccentric position, i.e., occupying a single half-field, reduced collinearity error. With additional displacement which produced a gap there was a rebound of induction effect. Exp. 1b indicated that an eccentric induction segment does not produce the usual strength or pattern of bias as a function of its orientation relative to the test segment. Exp. 2a suggested that the strength of induction effect is a function of symmetry within the half-fields rather than the lengths of the segments per se. Finally, in Exp. 2b the strength of induction was a joint function of the position of a short segment within one half-field and the length of another segment which stimulated the other half-field. The effect showed a complex oscillation with changes in position. We discuss the induction mechanism as beginning with "contour filters" which register the induction segment(s) and which combine their responses on the basis of "tandem activation" of the close half-fields.

Classical geometric illusion effects with nonclassical stimuli: angular induction from decomposing lines into point arrays

Angular induction is the process by which one line segment can bias judgment of orientation and/or collinearity of another segment, and it has been established that the magnitude of error is a determinate function of the relative angle between the two. We examined how these known relationships are affected by decomposing the induction segment into an array of scattered points. The bias that was produced by such arrays was found to be consistent with a formal model of angular induction, with the strength of the effect decreasing as the scatter among the points was increased. This decline in strength was almost linear with a logarithmic transform of the dimensions of the stimulus array. We also evaluated the hypothesis that the induction stimulus is detected by one or more channels--for example, neurons--for which the sensitivity profiles are modeled as Gabor wavelets. The change in induction strength with increasing point scatter was not predicted by a single width of channel. However, the combined activity of an ensemble of channels that differed in width did match the perceptual effects if one also stipulated that each channel would respond maximally to a fine-line stimulus.

Angular induction as a function of the length and position of segments and gaps

The perceptual distortions which are manifested in the Poggendorff illusion can be studied with the use of a more restricted set of stimulus elements. Experiments were designed in which angular induction effects between two line elements, known respectively as the test segment and induction segment, were evaluated. In some stimulus configurations the induction 'segment' consisted of a tandem pair of segments. Previous studies had shown that the induction segment will bias operant judgments of collinearity for a test segment, this effect being a function of the relative angle between the two. Six experiments are reported, in which the length and position of segments in relation to the tip of the test segment were varied. It was found that substantial induction is produced by a very short segment, and that this can bias judgment even when its displacement spans more than 10 deg of visual angle. Several aspects of the data suggest that the strength of effect is a log-linear function of segment position. However, the results from displacement of single or tandem segments do not conform to predictions based on length/response summation, and thus do not support a linear-systems approach. Neural substrates for these interactions are given brief attention.

Collinearity judgment as a function of induction angle

The misalignment which is seen in the Poggendorff illusion can be studied with better control by using a configuration which has only two line segments. Two experiments were conducted in which subjects judged collinearity of a test segment, this judgment being subjected to a biasing influence from a second (induction) segment. Exp. 1 held the test segment at one of three orientations relative to the observer (30 degrees, 45 degrees, and 60 degrees) and systematically varied the orientation of the induction segment in 15 degrees increments through the range of possible positions. The orientation of the page relative to the observer was varied as well. Exp. 2 varied the test segment through a greater range of angles and sampled more levels of induction segment orientation. Analysis indicated that projection errors follow orderly rules similar in kind to but different in magnitude from those observed for the Tilt Illusion, most notably, (a) misprojection is greatest when the orientation of the interfering line is similar to that of the line segment being projected and (b) the strength of this influence decreases as the relative angle becomes orthogonal. Also, the orientation of the segment being projected relative to the observer serves to modulate the strength of the basic induction effect. These perceptual interactions are discussed in relation to neural models for orientation selectivity.

Anomalous and luminance contours produce similar angular induction effects

One can shear a pattern of lines to produce an anomalous contour which has a perceptual influence similar to that of a straight line segment. Illusion effects have been found with configurations which contain these anomalous contours, as well as cross adaptation with respect to luminance contours. We have found that sheared-line contours will bias judgment of collinearity, ie perceived alignment, of a luminance contour. The angular induction effects are similar to those reported for interactions between luminance contours, and the same equation can be used to model both kinds of data. The results of this experiment support the neuroreductionist view that anomalous and luminance contours are processed at the same level of the nervous system. Additionally, we suggest that with both types of contour the perceptual system registers and responds to the alignment of local brightness differentials.

Angular induction is modulated by the orientation of the test segment but not its length

Angular induction is the basic process by which the orientation of line segments can affect the perceived orientation of other segments as well as their alignment. In this laboratory, we have found that the effect on alignment follows approximately linear rules, with the inducing segment having its greatest influence when its orientation is near to that of the segment being judged. Other laboratories, however, have reported peak effects when the relative angle between the two is at 45 degrees, and with the inducing segment being aligned with one of the cardinal axes of the observer. It has been said that the length of the test segment being judged is a critical factor, but the first experiment of the present study shows a similar linear decline of induction strength irrespective of test segment length. The second experiment indicates that the orientation of the test segment relative to the observer modulates the induction to determine the location of peak effects. A two-factor linear model predicts the observed pattern of results.