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PubMed2005

Food insecurity affects school children's academic performance, weight gain, and social skills.

Food insecurity has been associated with diverse developmental consequences for U.S. children primarily from cross-sectional studies. We used longitudinal data to investigate how food insecurity over time related to changes in reading and mathematics test performance, weight and BMI, and social skills in children. Data were from the Early Childhood Longitudinal Study-Kindergarten Cohort, a prospective sample of approximately 21,000 nationally representative children entering kindergarten in 1998 and followed through 3rd grade. Food insecurity was measured by parent interview using a modification of the USDA module in which households were classified as food insecure if they reported > or =1 affirmative response in the past year. Households were grouped into 4 categories based on the temporal occurrence of food insecurity in kindergarten and 3rd grade. Children's academic performance, height, and weight were assessed directly. Children's social skills were reported by teachers. Analyses examined the effects of modified food insecurity on changes in child outcomes using lagged, dynamic, and difference (i.e., fixed-effects) models and controlling for child and household contextual variables. In lagged models, food insecurity was predictive of poor developmental trajectories in children before controlling for other variables. Food insecurity thus serves as an important marker for identifying children who fare worse in terms of subsequent development. In all models with controls, food insecurity was associated with outcomes, and associations differed by gender. This study provides the strongest empirical evidence to date that food insecurity is linked to specific developmental consequences for children, and that these consequences may be both nutritional and nonnutritional.

Attitude to Health↗
PubMed1982

Acute care of the high-level quadriplegic patient.

Four months post-injury, Mark is into the ongoing rehabilitation phase of his hospitalization. He is free of continuous ventilator support with a vital capacity of 1200 cc. Neurologically, his level has descended to the C5 level, which has allowed him to function with moderate assistance from a motorized wheelchair. He is still immobilized in a Halo vest which will be removed when X-ray examination reveals that adequate fusion has occurred. Mark has not developed pulmonary embolus. After an initial problem with orthostatic hypotension, he can sit upright without symptomatology. Although he will probably continue to have difficulty with temperature regulation, Mark has learned how to control his environment in order to maintain his comfort and safety. Bowel training was difficult because of Mark's initial problem with paralytic ileus. With persistent adherence to the bowel program, however, Mark has become bowel continent. This process was facilitated once he was able to be mobilized and use a bedside commode. Mark continues on his bladder retraining program. As could be anticipated with an adolescent patient, adherence to the strict program of fluid regulation and restriction was difficult. It is anticipated that Mark will eventually be catheter-free and bladder continent in the future. Mark will require two to three months of further rehabilitation, after which he will return to his home and school. Mark faces a future centered from a wheelchair. With adequate medical, nursing, psychological, social and vocational follow-up, however, he can live a near normal life-span. With a positive support system he can build on the comprehensive care he received initially, and rebuild a life for himself.

Adolescent↗
PubMed1998

Ictal behaviors during nonepileptic seizures differ in patients with temporal lobe interictal epileptiform EEG activity and patients without interictal epileptiform EEG abnormalities.

PURPOSE: Ictal behaviors during psychogenic nonepileptic seizures (NES) vary considerably among individuals, and can closely resemble common semiologies of epileptic seizures (ES). We tested the hypothesis that behaviors during NES in patients who have temporal spikes would more closely resemble behaviors during ES in patients with temporal lobe epilepsy than would behaviors during NES in patients who do not have EEG spikes. METHODS: We identified 20 patients who had interictal temporal EEG spikes and EEG-video recorded NES (Study Group), 133 patients with temporal EEG spikes and recorded ES, without NES (Epileptic Group), and 24 patients with recorded NES and no epileptiform EEG abnormalities, without ES (Nonepileptic Group). RESULTS: The hypothesis was supported with regard to ictal motor behaviors. Motionless staring or complex automatisms occurred mainly during NES in the Study Group and during ES in the Epileptic Group. In contrast, convulsive movements or flaccid falls were most common during NES in the Nonepileptic Group. Duration of unresponsiveness was longer, and there were fewer postictal states in NES both in the Study and Nonepileptic Groups. Unresponsiveness was briefer and postictal states were more consistent in ES in the Epileptic Group, however. CONCLUSIONS: Stereotyped motor activities during NES presumably represent learned behaviors. Processes underlying acquisition of ictal behaviors of NES probably differ in patients with interictal epileptiform EEG abnormalities compared to those without. Prior experiences and temporal lobe dysfunctions that are associated with epilepsy, and psychological characteristics that are unrelated to interictal epileptic dysfunctions, may determine ictal behaviors during NES.

Adult↗
PubMed1999

The effects of acute and chronic alcohol ingestion on outcome following multiple episodes of mild traumatic brain injury in rats.

OBJECTIVE: Recent studies suggest that in some circumstances, alcohol intoxication at the time of severe head injury may be neuroprotective. The objective of this study was to determine the effect of acute and chronic alcohol ingestion on outcome in rodents sustaining multiple episodes of mild traumatic brain injury while intoxicated. METHOD: For two weeks before experimentation, adult male Sprague-Dawley rats received intoxicating levels of 95% ethanol (3 g/kg) or normal saline (NS) every other day by orogastric instillation. On the day of experimentation, the animals were randomized to receive alcohol or NS. Two hours later, the animals received either mild (1.2 +/- 0.4 ATA) fluid percussion injury (FPI) or no injury. The injured animals received a total of three episodes of FPI (once every four days). Mean reflex recovery time (RRT) was determined (seconds +/- SEM) immediately after each episode. Mean latency time (seconds +/- SEM) for Morris Water Maze (MWM) performance was assessed at post-trauma days 11-19. RESULTS: The chronic alcohol-exposed (CA) and the non-alcohol-exposed (NA) animals intoxicated when injured had prolonged escape, righting, and corneal RRTs after each FPI compared with the nonintoxicated injured animals and the non-injured shams. However, the CA animals had significantly shorter RRTs when compared with the NA rats. All the injured animals had MWM deficits on testing days 1-6 compared with the noninjured controls. On the last two MWM testing days, the injured NA animals had significantly better MWM performance than the injured CA rats. CONCLUSIONS: The injured intoxicated CA animals had a more rapid recovery of reflexes compared with the injured intoxicated NA animals. Despite initial MWM deficits, the injured NA rodents eventually began to learn the MWM. The injured CA rats never learned the maze. Under the conditions of this study, acute alcohol intoxication at the time of multiple episodes of minor head trauma did not provide neuroprotection for NA or CA rodents.

Acute Disease↗
PubMed1997

Language acquisition and use: learning and applying probabilistic constraints.

What kinds of knowledge underlie the use of language and how is this knowledge acquired? Linguists equate knowing a language with knowing a grammar. Classic "poverty of the stimulus" arguments suggest that grammar identification is an intractable inductive problem and that acquisition is possible only because children possess innate knowledge of grammatical structure. An alternative view is emerging from studies of statistical and probabilistic aspects of language, connectionist models, and the learning capacities of infants. This approach emphasizes continuity between how language is acquired and how it is used. It retains the idea that innate capacities constrain language learning, but calls into question whether they include knowledge of grammatical structure.

Adult↗
PubMed2000

Toward optimal classifier system performance in non-Markov environments.

Wilson's (1994) bit-register memory scheme was incorporated into the XCS classifier system and investigated in a series of non-Markov environments. Two extensions to the scheme were important in obtaining near-optimal performance in the harder environments. The first was an exploration strategy in which exploration of external actions was probabilistic as in Markov environments, but internal "actions" (register settings) were selected deterministically. The second was use of a register having more bit-positions than were strictly necessary to resolve environmental aliasing. The origins and effects of the two extensions are discussed.

Algorithms↗
PubMed2006

Prediction of protein continuum secondary structure with probabilistic models based on NMR solved structures.

BACKGROUND: The structure of proteins may change as a result of the inherent flexibility of some protein regions. We develop and explore probabilistic machine learning methods for predicting a continuum secondary structure, i.e. assigning probabilities to the conformational states of a residue. We train our methods using data derived from high-quality NMR models. RESULTS: Several probabilistic models not only successfully estimate the continuum secondary structure, but also provide a categorical output on par with models directly trained on categorical data. Importantly, models trained on the continuum secondary structure are also better than their categorical counterparts at identifying the conformational state for structurally ambivalent residues. CONCLUSION: Cascaded probabilistic neural networks trained on the continuum secondary structure exhibit better accuracy in structurally ambivalent regions of proteins, while sustaining an overall classification accuracy on par with standard, categorical prediction methods.

Algorithms↗
PubMed2002

Release dependence to a paired stimulus at a synaptic release site with a small variable pool of immediately releasable vesicles.

Monte Carlo simulations were performed on a release model based on experimental data from single glutamatergic synapses containing a single release site in the hippocampal CA1 region of the neonatal rat. These simulations explored what can be learned about the release process by examining how the release probability in response to the second stimulus (P(2)) of a paired stimulus to a synapse depends on the release in response to the first stimulus. Comparisons between experimental data from a number of individual synapses and the simulated data support the notion that the immediately releasable vesicle pool is small (approximately one) and shows substantial intertrial variation. The simulations also show that the release dependence of P(2) is not necessarily an indicator of either intertrial variation in Ca(2+) influx, feedback effects of released transmitter, or activation failure of the axon.

Animals↗
PubMedDate not supplied

Using APV (adjusted present value): a better tool for valuing operations.

Anyone who learned valuation techniques more than a few years ago is probably due for a refresher course. For the past 25 years, managers have been taught that the best practice for valuing assets-that is, an existing business, factory, product line, or market position-is to use a discounted-cash-flow (DCF) methodology. That is still true. But the particular version of DCF that has been accepted as the standard-using the weighted-average cost of capital (WACC)-is now obsolete. Today's better alternative, adjusted present value (APV), is especially versatile and reliable. It will likely replace WACC as the DCF methodology of choice among generalists. Like WACC, APV is used to value operations, or assets-in-place-that is, any existing asset that will generate a stream of future cash flows. Timothy Luehrman explains APV and walks readers through a case example designed to teach them how to use it. He argues that APV always works when WACC does-and sometimes when WACC doesn't, because it requires fewer restrictive assumptions. And APV is less prone to yield serious errors than WACC is. But, most important, general managers will find that APV's power lies in the managerially relevant information it provides. APV can help managers analyze not only how much an asset is worth but also where the value comes from.

Accounts Payable and Receivable↗
PubMed2001

General practice research. Problems and solutions in participant recruitment and retention.

BACKGROUND: Increasing interest in general practice research, especially postal surveys, has been met with decreasing response rates. Prospective, longitudinal surveys pose additional concerns for general practice researchers, one of the major problems being sample attrition after project commencement. OBJECTIVE: This article draws on the authors' experiences from seven studies conducted by them to identify useful strategies for researchers who need to recruit general practitioners and/or their patients, with particular reference to retaining participants across time. A list of issues, lessons learned and possible strategies was developed which, although not exhaustive, probably reflects those commonly encountered in many general practice studies. DISCUSSION: The issues identified here are not necessarily new, but it is useful to revisit such issues and to review and reiterate methods and processes, as even experienced researchers encounter problems from time to time. Studies involving prolonged participation especially, require diligent consideration of likely recruitment/retention problems.

Australia↗
PubMed2002

[Can stress echocardiography by quantified?].

Stress echocardiography has been validated for the evaluation of myocardial ischaemia and viability despite a semi-quantitative interpretation based on visual analysis of segmental myocardial thickening. The technique remains, therefore, partially subjective, which probably affects its diagnostic value and reproducibility, especially during the learning period of a non-expert operator. A first step towards better reproducibility was made possible by Second Harmonic imaging and standardised interpretation according to the recommendations of the American Society of Echocardiography. The quantification is based on the analysis of numerical data obtained by Doppler tissue imaging or color kinesis. Doppler Tissular Imaging in the pulsed mode with analysis of transparietal velocity gradients or regional deformation is currently under evaluation. However, the use of threshold values for myocardial velocities has been of little diagnostic value and the use of algorithms adjusted for age, heart rate and gender are necessary. Another approach is that of colour coding of endocardial displacement (Color Kinesis) with automatic contour detection. This relatively easy technique requires a shorter post-processing and the initial results are encouraging.

Echocardiography, Doppler, Color↗
PubMedDate not supplied

[The characteristics of probabilistic prognosis and of the orienting reaction in children with learning difficulties].

Middle-aged school-children were examined with learning disabilities, differentiated by the parameters of probabilistic prognosis in two subgroups: with disturbances of attention (1) and memory (2). The first subgroup differed from the norm by intensified reaction of desynchronization of the projection areas of the cortex to irrelevant stimuli. Relevant information evoked an increase of activation of the associative zones, less expressed than in the norm. In the second subgroup a weak involvement of associative cortical areas in the reaction of desynchronization to relevant stimuli correlated with insufficient formation of alpha 2-rhythm and high frequency of meeting the signs of dysfunction of mesodiencephalic brain structure. The results are discussed in the aspect of the role of neurophysiological mechanisms of regulation and trace fixation for the formation of the integrative brain activity in the ontogenesis.

Attention↗
PubMed2004

Pune low birth weight study--cognitive abilities and educational performance at twelve years.

OBJECTIVE: To assess the intelligence, visuo-motor perception, motor competence and school performance of children with birth weight less than 2000 grams, at the age of 12 years. DESIGN: Prospective cohort study. SETTING: Infants discharged from a Neonatal Special Care Unit of a referral hospital with birth weight less than 2000 g between 1987-89 and followed up in the High Risk Clinic. METHODS: The children were assessed by the Weschler's Intelligence Scale, Bender Gestalt test for visuo-motor perception, Wide Range Achievement Test for specific learning disability, Draw-a-Person screening test for emotional problems and Movement Assessment Battery for motor competence. Academic achievement was also scrutinised. RESULTS: One hundred and eighty children weighing less than 2000 grams at birth and ninety control children were assessed. The mean IQ of the study group was normal (89.5 +/- 16.9), though significantly lower than that of controls (97.2 +/- 14.1; p<0.05). Pre term SGA children had the lowest mean IQ (85.4 +/- 17.7). In the 78 VLBW children, there were 12 (15.4%) mentally retarded children as compared to only 3 (3.3%) amongst controls (p<0.001). There were only 3 (3.8%) 'bright' children among the VLBW group, as compared to 20 (22.2%) in the control group (p<0.001). Visuo-motor perception and motor competence of the study group was poor, and they had writing and mathematics learning disability, especially the preterm SGA and VLBW group. Academic achievement was poor and the incidence of borderline intelligence was 24.4%, which has increased from 13.4% at 6 years. CONCLUSIONS: The intelligence and academic performance of the children weighing less than 2000 grams is significantly lower than that of controls, though within normal limits. They also have poor visuo-motor perception, motor incompetence, reading and mathematics learning disability. The preterm SGA and VLBW children had the poorest cognitive abilities.

Age Distribution↗