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The hippocampus, critical for learning and memory, undergoes substantial changes early in life. Investigating the developmental trajectory of hippocampal structure and function requires an accurate method for segmenting this region from anatomical MRI scans. Although manual segmentation is regarded as the "gold standard" approach, it is laborious and subjective. This has fueled the pursuit of automated segmentation methods in adults. However, little is known about the reliability of these automated protocols in infants, particularly when anatomical scan quality is degraded by head motion or the use of shorter and quieter infant-friendly sequences. During a task-based fMRI protocol, we collected quiet T1-weighted anatomical scans from 42 sessions with awake infants aged 4-23 months. Two expert tracers first segmented the hippocampus in both hemispheres manually. The resulting inter-rater reliability (IRR) was only moderate, reflecting the difficulty of infant segmentation. We then used four protocols to predict these manual segmentations: average adult template, average infant template, FreeSurfer software, and Automated Segmentation of Hippocampal Subfields (ASHS) software. ASHS generated the most reliable hippocampal segmentations in infants, exceeding the manual IRR of experts. Automated methods thus provide robust hippocampal segmentations of noisy T1-weighted infant scans, opening new possibilities for interrogating early hippocampal development.

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In a dairy production system where cows are grazing for a large portion of their lactation, little attention has been afforded to investigating multiple indicators of welfare for risk factors associated with the housing period. Yet regardless of the length of the housing period, cows still experience the positive and negative welfare impacts of both indoor and outdoor environments in a hybrid system. Thus, the objective of this study was to identify risk factors for indicators of dairy cow welfare during the housing period in a spring-calving, hybrid pasture-based system. Herd-level scores for seven indicators of welfare (locomotion, body condition, ocular and nasal discharge, integument damage, tail injury and human avoidance response) were collected from 82 Irish dairy farms during the housing period (October - February). Data were analysed using multiple beta regression or zero-inflated beta regression to identify associations between these welfare indicators and measured herd-level housing, resource and management factors. Thirty-six unique risk factors were associated with one or more welfare indicators (P < 0.05). Analyses identified two risk factors for body condition < 3.0 and four for body condition > 3.5, the target range during the housing period. Four risk factors were identified for each of ocular discharge, nasal discharge and avoidance response of > 1 m from human approach. Six risk factors each were associated with the proportion of lame cows and integument damage to the head-neck-back or hindquarter regions. The greatest number of risk factors, 12, were associated with tail injury (broken, lacerated or incomplete tails). Risk factors associated with multiple indicators of welfare were cow comfort index (tail lacerations and hindquarter integument damage), cubicle width (broken and incomplete tails), shed floor slipperiness (lameness and head-neck-back integument damage), shed light-level (tail lacerations, avoidance response and below target body condition), shed passage width (broken tails and head-neck-back integument damage) and presence (incomplete tails) or absence (broken tails) of a collecting yard backing gate. With the large number of risk factors associated with tail injury, continued research is necessary to identify causes and determine prevention methods to contribute to improved overall welfare of dairy cows. Housing features meeting recommended guidelines from the literature were frequently associated with greater negative indicators of welfare. In light of this, housing guidelines may benefit from regular re-evaluation to ensure facilities meet the welfare needs of cows during the housing period.

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Lameness is a symptom of a painful disorder affecting the limbs, which impacts dairy cow welfare and productivity. Lameness is primarily caused by hoof lesions. The prevalence of different lesion types can differ depending on environmental conditions and farm management practices. The aims of this observational study were to establish the cow-level and herd-level lesion prevalence during both housing and grazing periods in a partly housed, pasture-based system, establish the prevalence of lesions always associated with pain ("alarm" lesion), identify the lesions associated with a higher lameness score, determine relationships between lesions, and identify risk factors for digital dermatitis. On 98 farms during the grazing period and on 74 of the same farms during the housing period, every cow was lameness scored (0-3 lameness scoring scale), and the hind hooves of lame cows (score 2 and 3) were examined (maximum 20 cows per visit) and the prevalence of each lesion type recorded. To gather data on potential predictors for the risk factor analysis, a questionnaire with the farmer was conducted on lameness management practices and infrastructure measurements were taken at each visit. Cow-level data were also collected (e.g., parity, breed, milk yield, and so on). Noninfectious lesions were found to be more prevalent than infectious lesions in this system type. The most prevalent lesion types during both grazing and housing periods were white line separation, sole hemorrhages and overgrown claws; all remaining lesions had a cow-level prevalence of less than 15%. The cow-level prevalence of alarm lesions was 19% during the grazing period and 25% during the housing period; the most prevalent alarm lesion was sole ulcers during both periods. We found significantly more foreign bodies within the hoof sole (grazing = 14%, housing = 7%) and overgrown claws (grazing = 71%, housing = 55%) during the grazing period compared with the housing period. Cows with foul of the foot, sole ulcer, white line abscess, toe necrosis or an amputated claw had higher odds of being more severely lame, compared with mildly lame. The strongest correlation between lesions were between toe necrosis and digital dermatitis (r = 0.40), overgrown claws and corkscrew claws (r = 0.33), and interdigital hyperplasia and digital dermatitis (r = 0.31) at herd level. At the cow level, the strongest correlation was between overgrown claws and corkscrew claws (r = 0.27), and digital dermatitis and heel erosion (r = 0.22). The farmers' perception of the presence of digital dermatitis (and lameness) was significantly correlated with the actual presence of digital dermatitis recorded. Additional risk factors for the presence of digital dermatitis were cow track and verge width near the collecting yard, and stone presence on the cow tracks. Results from this study help further our understanding of the causes of lameness in partly housed, pasture-based dairy cows, and can be used to guide prevention and treatment protocols.

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BACKGROUND: Lameness is a painful disease, which negatively impacts dairy cow production and welfare. The aim of this observational study was to determine herd lameness prevalence, describe current lameness management practices and identify the presence of established risk factors for lameness on Irish pasture-based dairy farms. Farms were visited once during grazing (99 farms) and again during housing (85 farms). Lameness scoring was carried out at each visit (AHDB 0-3 scale); cows were classified as lame if they scored two or three. Farm management practices and infrastructure characteristics were evaluated via farmer questionnaires and direct measurements of farm infrastructure. RESULTS: Median herd-level lameness prevalence was 7.9% (interquartile range = 5.6 - 13.0) during grazing and 9.1% (interquartile range = 4.9 - 12.0) during housing; 10.9% of cows were lame at a single visit and 3.5% were lame at both visits (chronically lame or had a repeat episode of lameness). Fifty-seven percent of farmers were not familiar with lameness scoring and only one farm carried out lameness scoring. Only 22% of farmers kept records of lame cows detected, and 15% had a lameness herd health plan. Twenty-eight percent of farmers waited more than 48 h to treat a lame cow, and 21% waited for more than one cow to be identified as lame before treating. Six percent of farmers carried out routine trimming and 31% regularly footbathed (> 12 times per year). Twelve percent put severely lame cows in a closer paddock and 8% stated that they used pain relief to treat severely lame cows. Over 50% of farms had at least one cow track measurement that was classified as rough or very rough, and cow tracks were commonly narrow for the herd size. On 6% of farms, all cubicle beds were bare concrete (no matting or bedding) and on a further 6% of farms, there was a combination of cubicles with and without matting or bedding. On 56% of farms, all pens contained less than 1.1 cubicles per cow and on 28% of farms, a proportion of pens contained less than 1.1 cubicles per cow. CONCLUSIONS: Overall, this study identified infrastructure and management practices which could be improved upon. The comparatively low lameness prevalence demonstrated, compared to fully housed systems, also highlights the benefits of a pasture-based system for animal welfare; however, there remains scope for improvement.

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Large-scale investigation of risk factors for multiple welfare indicators in hybrid pasture-based dairy systems is scarce. Our objective was to identify grazing season welfare risk factors on spring-calving, hybrid pasture-based dairy farms where cows experience periods of both grazing and housing. Herd-level data were collected from visits to 93 farms in the primary dairy producing counties of Ireland. Zero-inflated beta regression analysis was used to assess potential associations between categorical management and resource factors, and commonly measured animal-based welfare indicators: locomotion, body condition, nasal and ocular discharge, tail injury, integument damage, and avoidance behaviour. To account for small sample size due to elimination of farms with missing data, analyses were conducted on both a dataset of complete cases, and a dataset where missing values had been substituted for the most common response through single imputation. Resulting risk factors from both methods of analysis were compared for each indicator. Analyses identified 14 risk factors associated with one or more welfare indicators. The proportion of lame cows was positively associated with a previous housing period of four months or more compared to three months, all cubicles being outside recommended lengths and repairing roadways every two to three years compared to either yearly or more than every four years to never. The proportion of cows below minimum target grazing body condition score of 2.75 was negatively associated with participation in elective herd disease-testing in the past year. The proportion of cows with tail lacerations was positively associated with using a single breeding method, not employing part-time staff and not using brisket boards in cubicles. Previous housing period length was significantly associated with the proportion of cows with integument damage, although the direction of association was unclear. Moderate to severe nasal discharge was positively associated with collecting yard holding times of ≤ 60 min compared to > 90 min. Ocular discharge was negatively associated with manual health record-keeping and a collecting yard below the recommended area of 1.4 m2/cow. The proportion of cows with an avoidance response distance > 1 m was positively associated with herding cows without a dog present and having no additional full-time staff. Multiple risk factors were related to the housing period, suggesting that potential carry-over effects of housing management on welfare persist into the grazing period. This emphasizes the need for research to consider both housing and grazing periods in the management of welfare in hybrid pasture-based systems.

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Lameness in dairy cows is a major animal welfare concern and has substantial economic impact through reduced production and fertility. Previous risk factor analyses have focused on housed systems, rather than those where cows were grazed for the majority of the year and housed only for the winter period. Therefore, the aim of this observational study was to identify a robust set of cow-level and herd-level risk factors for lameness in a pasture-based system, based on predictors from the housing and grazing periods. Ninety-nine farms were visited during the grazing period (April 2019-September 2019), and 85 farms were revisited during the housing period (October 2019-February 2020). At each visit, all lactating cows were scored for lameness (0 = good mobility, 1 = imperfect mobility, 2 = impaired mobility, 3 = severely impaired mobility), and potential herd-level risk factors were recorded through questionnaires and infrastructure measurements. Routine cow-level management data were also collected. Important risk factors for lameness were derived though triangulation of results from elastic net regression, and from logistic regression model selection using modified Bayesian information criterion. Both selection methods were implemented using bootstrapping. This novel approach has not previously been used in a cow-level or herd-level risk factor analysis in dairy cows, to the authors' knowledge. The binary outcome variable was lameness status, whereby cows with a lameness score of 0 or 1 were classed as non-lame and cows with a score of 2 or 3 were classed as lame. Cow-level risk factors for increased lameness prevalence were age and genetic predicted transmitting ability for lameness. Herd-level risk factors included farm and herd size, stones in paddock gateways, slats on cow tracks near the collecting yard, a sharper turn at the parlor exit, presence of digital dermatitis on the farm, and the farmers' perception of whether lameness was a problem on the farm. This large-scale study identified the most important associations between risk factors and lameness, based on the entire year (grazing and housing periods), providing a focus for future randomized clinical trials.

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Thousands of functional magnetic resonance imaging (fMRI) studies have provided important insight into the human brain. However, only a handful of these studies tested infants while they were awake, because of the significant and unique methodological challenges involved. We report our efforts to address these challenges, with the goal of creating methods for awake infant fMRI that can reveal the inner workings of the developing, preverbal mind. We use these methods to collect and analyze two fMRI datasets obtained from infants during cognitive tasks, released publicly with this paper. In these datasets, we explore and evaluate data quantity and quality, task-evoked activity, and preprocessing decisions. We disseminate these methods by sharing two software packages that integrate infant-friendly cognitive tasks and eye-gaze monitoring with fMRI acquisition and analysis. These resources make fMRI a feasible and accessible technique for cognitive neuroscience in awake and behaving human infants.

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BACKGROUND: Health care professionals play a critical role in preventing and managing childhood obesity, but the American Academy of Pediatrics recently stressed the importance of using sensitive and nonstigmatizing language when discussing weight with children and families. Although barriers to weight-related discussions are well known, there are few evidence-based recommendations around communication best practices. Disability populations in particular have previously been excluded from work in this area. The objectives were to present the findings of a recent scoping review to children with and without disabilities and their caregivers for their reactions; and to explore the experiences and perceptions of the children and their caregivers regarding weight-related communication best practices. METHODS: Focus group and individual interviews were conducted with 7-18-year olds with and without disabilities and their caregivers. The interview guide was created using findings from a recent scoping review of weight-related communication best practices. Inductive thematic analysis was employed. RESULTS: Eighteen children (9 boys; 7 children with disabilities) and 21 caregivers (17 mothers, 1 step-father, 3 other caregivers) participated in 8 focus group and 7 individual interviews. Preferred communication strategies were similar across those with and without disabilities, although caregivers of children with autism spectrum disorder endorsed more concrete approaches. Discussions emphasizing growth and health were preferred over weight and size. Strengths-based, solution-focused approaches for weight conversations were endorsed, although had not been widely experienced. CONCLUSION: Perceptions of weight-related communication were similar across stakeholder groups, regardless of children's disability or weight status. Participants generally agreed with the scoping review recommendations, suggesting that they apply broadly across different settings and populations; however, tailoring them to specific circumstances is critical. Empirical evaluations are still required to examine the influence of weight-related communication on clinically important outcomes, including behaviour change and family engagement in care.

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OBJECTIVES: To determine the feasibility and preliminary impact of an electronic health (eHealth) screening, brief intervention and referral to treatment (SBIRT) delivered in primary care to help parents prevent childhood obesity. METHODS: Parents of children (5-17 years) were recruited from a primary care clinic. Children's measured height and weight were entered into the SBIRT on a study-designated tablet. The SBIRT screened for children's weight status, block randomized parents to one of four brief interventions or an eHealth control and provided parents with a menu of optional obesity prevention resources. Feasibility was determined by parents' interest in, and uptake of, the SBIRT. Preliminary impact was based on parents' concern about children's weight status and intention to change lifestyle behaviours post-SBIRT. RESULTS: Parents (n = 226) of children (9.9 ± 3.4 years) were primarily biological mothers (87.6%) and Caucasian (70.4%). The proportion of participants recruited (84.3%) along with parents who selected optional resources within the SBIRT (85.8%) supported feasibility. Secondary outcomes did not vary across groups, but non-Caucasian parents classified as inaccurate estimators of children's weight status reported higher levels of concern and intention to change post-SBIRT. CONCLUSIONS: Our innovative, eHealth SBIRT was feasible in primary care and has the potential to encourage parents of unhealthy weight children towards preventative action.

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Healthy lifestyle behaviours are key to successful weight management, but have proven to be challenging to attain for adolescents with obesity. The purpose of our scoping review was to (i) describe barriers and enablers that adolescents with obesity encounter for healthy nutrition, physical activity, sedentary behaviour and sleep habits and (ii) identify gaps in the literature. We adhered to established methodology for scoping reviews. Six databases were searched (1980-June 2016) for original articles published in English or French that focused on lifestyle behaviours of 13- to 17-year-olds in paediatric weight management. Following screening and data extraction, findings of selected articles were synthesized thematically using a social ecological framework. Stakeholder consultation (n = 20) with adolescents with obesity and health professionals was completed to enhance methodological rigour. Our search yielded 17 articles for inclusion, including 546 unique participants. Barriers to healthy nutrition and physical activity were more consistently related to individual-level and interpersonal-level factors; enablers tended to be linked with interpersonal-level factors. Knowledge gaps identified related to sedentary behaviour and sleep as well as environmental and policy levels of influence. Our review revealed that some barriers and enablers were unique to adolescents with obesity, which were either within or beyond their control. These findings highlight the importance of multilevel interventions to enable healthy lifestyle behaviours for weight management.

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While reducing the burden of brain disorders remains a top priority of organizations like the World Health Organization and National Institutes of Health, the development of novel, safe and effective treatments for brain disorders has been slow. In this paper, we describe the state of the science for an emerging technology, real time functional magnetic resonance imaging (rtfMRI) neurofeedback, in clinical neurotherapeutics. We review the scientific potential of rtfMRI and outline research strategies to optimize the development and application of rtfMRI neurofeedback as a next generation therapeutic tool. We propose that rtfMRI can be used to address a broad range of clinical problems by improving our understanding of brain-behavior relationships in order to develop more specific and effective interventions for individuals with brain disorders. We focus on the use of rtfMRI neurofeedback as a clinical neurotherapeutic tool to drive plasticity in brain function, cognition, and behavior. Our overall goal is for rtfMRI to advance personalized assessment and intervention approaches to enhance resilience and reduce morbidity by correcting maladaptive patterns of brain function in those with brain disorders.

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Crossbred pigs (n = 216) were used to test the effects of phase-feeding beef tallow (BT) and yellow grease (YGr) on live performance, carcass characteristics, and fatty acid composition of subcutaneous (s.c.) fat depots of growing-finishing swine. Pigs were blocked by initial BW (26.0 ± 5.3 kg) before allotment to pens (6 pigs/pen), and pens (6 pens/block) were assigned randomly to 1 of 6 dietary treatments: 1) corn-soybean meal-based grower and finisher diets formulated with 4.7% YGr fed during all 5 feeding phases (YG15), 2) corn-soybean meal-based diets formulated with 5.0% BT fed during all 5 phases (BT15), 3) diets containing 5.0% BT fed during the first 2 phases and diets with 4.7% YGr fed the last 3 phases (YG345), 4) diets formulated with 5.0% BT fed during first 3 phases and diets containing 4.7% YGr fed during the last 2 phases (YG45), 5) diets containing 4.7% YGr fed during the first 3 phases and diets with 5.0% BT fed during the last 2 feeding phases (BT45), or 6) diets formulated with 4.7% YGr fed during the first 2 phases and diets with 5.0% BT fed during the last 3 phases (BT345). Overall performance was similar (P ≥ 0.06) among dietary treatments; however, overall ADG and ADFI increased (quadratic, P ≤ 0.05) with increasing days fed BT, but duration of dietary YGr did not affect ADG (P ≥ 0.22) or ADFI (P ≥ 0.30). There was no (P ≥ 0.23) effect of fat inclusion on carcass characteristics, but carcass lean yield decreased (linear, P = 0.02) as duration of YGr feeding increased from 37 to 103 d. Proportions of back fat SFA (quadratic, P = 0.03) and jowl fat MUFA (linear, P = 0.02) increased as the time fed BT increased from 47 to 103 d. Conversely, PUFA content of both s.c. fat depots increased (linear, P < 0.01) with increasing durations of dietary YGr. Moreover, quadratic slopes for linolenic (18:2n-6) and linolenic (18:3n-3) acids in jowl fat differed (P ≤ 0.05) between BT and YGr durations, indicating that the percentages of 18:2n-6 and 18:3n-3 increased at a greater rate with increasing time fed YGr than the rate of decreases in 18:2n-6 and 18:3n-3 associated with increasing time fed BT. Results of this study confirm that the fatty acid composition of s.c. fat depots are similar to that of the dietary fat source fed during the last 2 or 3 feeding phases, yet deposition rates of specific fatty acids appear to be dependent on the length of time pigs are fed a specific fat source.

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Crossbred pigs (n = 216) were used to test the effects of phase-feeding beef tallow (BT) and yellow grease (YGr) on fresh belly and bacon quality characteristics of growing-finishing swine fed dried distillers grains with solubles (DDGS). Pigs were blocked by initial BW (26.0 ± 5.3 kg) before allotment to pens (6 pigs/pen), and pens (6 pens/block) were assigned randomly to 1 of 6 dietary treatments: 1) corn-soybean meal-based grower and finisher diets formulated with 4.7% YGr fed during all 5 feeding phases (YG15); 2) corn-soybean meal-based diets formulated with 5.0% BT fed during all 5 phases (BT15); 3) diets containing 5.0% BT fed during the first 2 phases and diets with 4.7% YGr fed the last 3 phases (YG345); 4) diets formulated with 5.0% BT fed during first 3 phases and diets containing 4.7% YGr fed during the last 2 phases (YG45); 5) diets containing 4.7% YGr fed during the first 3 phases and diets with 5.0% BT fed during the last 2 feeding phases (BT45); or 6) diets formulated with 4.7% YGr fed during the first 2 phases and diets with 5.0% BT fed during the last 3 phases (BT345). All dietary treatments were formulated with 30% dried distillers grains with solubles (DDGS) during the first 3 phases, 15% DDGS in the fourth phase, and no DDGS during the last phase. Fresh belly quality data were collected on the left-side bellies, whereas bacon from the right-side bellies was prepared under commercial processing conditions. Additionally, USDA-certified No. 1 slices were collected for cooking characteristics and sensory panel evaluations. Bellies from the YG15-fed pigs were softer (P ≤ 0.05) than bellies from BT15-fed pigs; however, instrumentally measured belly firmness was not (P ≥ 0.06) different among treatments. Concentrations of palmitic, stearic, and oleic acids, as well as all SFA and all MUFA, were greater (P < 0.01) in bellies from BT15- than YG15-fed pigs. In contrast, proportions of linoleic acid, all PUFA, and iodine value were greater (P < 0.01) in belly fat from YG15-fed pigs in comparison with BT15-fed pigs. Yield of commercially processed bacon (P ≥ 0.06), mechanical bacon tenderness (P ≥ 0.69), and bacon palatability attributes (P ≥ 0.55) were not affected by the dietary treatments. Thus, results of this study indicated that phase-feeding BT to pigs fed diets formulated with DDGS produced minor improvements in fresh belly firmness due to greater proportions of SFA but had no effect on yields of commercially processed bacon or bacon quality characteristics.

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Coral growth rates (linear extension, density, calcification rates) of three fast-growing corals (Acropora, Montipora, Turbinaria) were studied in situ on Middle Reef, an inshore reef located on the central Great Barrier Reef (GBR), to assess the influence of changing environmental conditions on coral condition and reef growth. Middle Reef is subjected to both local (e.g. high sediment loads) and global (e.g. coral bleaching) disturbance events, usually associated with reduced coral growth. Results indicated, however, that Acropora growth rates (mean linear extension = 6.3 cm/year) were comparable to those measured at similar depths on offshore reefs on the GBR. Montipora linear extension (2.9 cm/year) was greater than estimates available from both clear-water and turbid reefs, and Turbinaria's dense skeleton (1.3 g/cm(3)) may be more resilient to physical damage as ocean pH falls. Coral growth was found to vary between reef habitats due to spatial differences in water motion and sediment dynamics, and temporally with lower calcification rates during the summer months when SSTs (monthly average 29 °C) and rainfall (monthly total >500 mm) were high. In summary, corals on Middle Reef are robust and resilient to their marginal environmental conditions, but are susceptible to anthropogenic disturbances during the summer months.

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AIMS: To evaluate a new range of chromogenic substrates for the detection of beta-galactosidase activity in coliforms and to compare their performance in agar media and broths. METHODS AND RESULTS: Sixteen novel galactoside substrates were prepared and incorporated into agar and broth. Their performance was compared using Escherichia coli (five strains), Salmonella (two strains), Enterobacter (two strains), Klebsiella, Pseudomonas, Listeria, Serratia, Shigella, Citrobacter, Proteus and Staphylococcus as well as pathological urine samples. The six substrates out of the initial 16 that showed the greatest sensitivity were VQE-gal, VQM-gal, VLPr-gal, VLE-gal, VLM-gal and VBzTM-gal, whose released chromophores were red, brown or purple. VQE-gal and VLPr-gal were studied in greater detail and were incorporated into agar medium. Coliform colonies appeared red and brown respectively, following incubation at 37 degrees C for 24 h; however, positive results were obtained within a working day. The VQE-gal medium was compared with some commercially available media. CONCLUSIONS: The range of substrates described can be used in broths as well as in agars. The VQE agar allows the detection of coliforms within a working day. VQE-gal medium proved to be more sensitive when compared to other available chromogenic media and allows the unambiguous detection of coliforms.

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One ubiquitous finding in functional magnetic resonance imaging studies is that repeated stimuli elicit lower responses than novel stimuli. In apparent contradiction, some studies have reported the exact opposite effect--greater responses to repeated than novel stimuli--in many of the same brain regions. Interestingly, these latter enhancement effects are typically obtained when stimuli have been degraded. To explore this observation, the present study examines the degree to which visual quality mediates repetition effects in a stimulus-selective ventral visual area. Subjects were presented with grayscale photographs of scenes that were either near or substantially above visual threshold, as determined by calibrating image contrast to behavioral performance. The presentation of 2 identical high-contrast scenes elicited lower blood oxygen level-dependent (BOLD) responses than the presentation of 2 different high-contrast scenes (repetition attenuation). Conversely, the presentation of 2 identical low-contrast scenes elicited greater BOLD responses than the presentation of 2 different low-contrast scenes (repetition enhancement). Neurophysiological studies suggest that repetition attenuation in ventral visual areas may reflect the reactivation of perceptual representations that have become sparse and selective as a result of prior experience, whereas repetition enhancement may reflect spared access to existing representations by severely degraded input.

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Procalcitonin (PCT) plasma levels and the fraction of CTLA-4-positive T cells are both elevated in acute Plasmodium falciparum malaria in human adults and the degree of elevation is positively correlated with other markers of disease severity, for example with parasitaemia. However, the clinical manifestations of malaria are strongly age-dependent and children from endemic areas carry the main disease burden. Therefore, we measured PCT plasma levels and CTLA-4 expression by T cells in four groups of children from the Ashanti Region in Ghana: asymptomatic children with or without parasitaemia, children with uncomplicated P. falciparum malaria and children with severe disease. PCT levels were highly elevated in both groups with acute malaria but they did not discriminate between uncomplicated and severe disease. In contrast, CTLA-4-expression by T cells was increased only in severe malaria. The fraction of CTLA-4 positive T cells in the blood of children with severe disease differed significantly from that in uncomplicated malaria, which was not elevated in spite of the high parasite loads observed in these children. This was unexpected, as in adults uncomplicated malaria is associated with a dramatic sixfold increase of the fraction of CTLA-4-positive T cells. The data from this study support the hypothesis that strong T cell activation as measured here by CTLA-4 expression is not just the by-product of a high parasite burden, but that it contributes to the pathogenesis of P. falciparum malaria.

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AIMS: The pathogen Bacillus cereus, which is associated with a number of foods including dairy products, was studied for its response to acid stress during the exponential phase. METHODS AND RESULTS: Bacillus cereus was found to adapt to acid stress (pH 4.6) when pre-exposed to a non-lethal, inducing pH of 6.3 or to inducing concentrations of heat, ethanol, salt or hydrogen peroxide. Cells were found to maintain their internal pH at a higher level than the external acid pH and adapted cells had a higher internal pH than unadapted cells. A constitutive acid-sensitive mutant that was also heat- and ethanol-sensitive was found to be capable of high levels of adaptation despite its lack of induction of proteins induced in the wild type by exposure to moderate pH (6.3) values. CONCLUSIONS: A number of proteins were found to be underexpressed in the mutant compared with the wild type at pH 6.3, including some with homology to ribosomal proteins and to the sporulation regulator RapK, while one differentially expressed band contained two proteins, one of which was homologous to the competence regulator CodY. SIGNIFICANCE AND IMPACT OF THE STUDY: The work has implications for the processing of B. cereus-associated foods by acidification. The linked developmental processes of stationary phase, sporulation and possibly competence appear to be involved in the response to acid stress.

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AIMS: The effects of stresses imposed on bacterial contaminants during food processing and treatment of packaging material were evaluated on the food pathogen Bacillus cereus. METHODS AND RESULTS: Conditions were established which allowed the cells to adapt to heat, ethanol and hydrogen peroxide stresses, but not to osmotic shock. Cross protection between stresses indicated a clear hierarchy of resistance with salt protecting against hydrogen peroxide, which protected against ethanol, which protected against heat shock. The cultures were shown to be most sensitive to heat, ethanol and oxidative stress at mid-exponential phase and to become resistant at stationary phase. Adaptive levels of stressor were found to induce synthesis of general stress and stress-specific proteins and differential accumulation of proteins was demonstrated between heat- or salt-stressed and unstressed cells. CONCLUSIONS: Sequencing revealed that a number of glycolytic enzymes were regulated by heat and osmotic shocks and that the chaperone GroEL was induced by heat shock. SIGNIFICANCE AND IMPACT OF THE STUDY: The implications of the physiological data in designing storage and processing conditions for food are discussed. The identification of stress-regulated proteins reveals a clear role for glycolysis in adaptation to heat shock and osmotic stress.

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OBJECTIVES: To evaluate the seriousness and frequency of violence and the degree of associated injury depicted in the 100 top-grossing American films of 1994. METHODS: Each scene in each film was examined for the presentation of violent actions on persons and coded by a systematic context-sensitive analytic scheme. Specific degrees of violence and indices of injury severity were abstracted. Only actually depicted, not implied, actions were coded, although both explicit and implied consequences were examined. RESULTS: The median number of violent actions per film was 16 (range, 0-110). Intentional violence outnumbered unintentional violence by a factor of 10. Almost 90% of violent actions showed no consequences to the recipient's body, although more than 80% of the violent actions were executed with lethal or moderate force. Fewer than 1% of violent actions were accompanied by injuries that were then medically attended. CONCLUSIONS: Violent force in American films of 1994 was overwhelmingly intentional and in 4 of 5 cases was executed at levels likely to cause significant bodily injury. Not only action films but movies of all genres contained scenes in which the intensity of the action was not matched by correspondingly severe injury consequences. Many American films, regardless of genre, tend to minimize the consequences of violence to human beings.

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