bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Mapping of Plant Height Quantitative Trait Loci in a Sorghum Association Population With Introgressed Dwarfing Genes
Authors: Brown Patrick J , Rooney William L , Franks Cleve , Kresovich Stephen
Published: September 2008

Of the four major dwarfing genes described in sorghum, only Dw3 has been cloned. We used association mapping to characterize the phenotypic effects of the dw3 mutation and to fine map a second, epistatic dwarfing QTL on sorghum chromosome 9 (Sb-HT9.1). Our panel of 378 sorghum inbreds includes 230 sorghum conversion (SC) lines, which are exotic lines that have been introgressed with dwarfing quantitative trait loci (QTL) from a common parent. The causal mutation in dw3 associates with reduced lower internode length and an elongation of the apex, consistent with its role as an auxin efflux carrier. Lines carrying the dw3 mutation display high haplotype homozygosity over several megabases in the Dw3 region, but most markers linked to Dw3 do not associate significantly with plant height due to allele sharing between Dw3 and dw3 individuals. Using markers with a high mutation rate and the dw3 mutation as an interaction term, significant trait associations were detected across a 7-Mb region around Sb-HT9.1, largely due to higher detection power in the SC lines. Conversely, the likely QTL interval for Sb-HT9.1 was reduced to ∼100 kb, demonstrating that the unique structure of this association panel provides both power and resolution for a genomewide scan.
Inducing Segmental Aneuploid Mosaicism in the Mouse Through Targeted Asymmetric Sister Chromatid Event of Recombination
Authors: Duchon Arnaud , Besson Vanessa , Pereira Patricia Lopes , Magnol Laetitia , Hérault Yann
Published: September 2008

Loss or gain of whole chromosomes, or parts of chromosomes, is found in various pathological conditions, such as cancer and aneuploidy, and results from the missegregation of chromosomes during cellular division or abnormal mitotic recombination. We introduce a novel strategy for determining the consequences of segmental aneuploid mosaicism, called targeted asymmetric sister chromatin event of recombination (TASCER). We took advantage of the Cre/loxP system, used extensively in embryonic stem cells for generating deletions and duplications of regions of interest, to induce recombination during the G2 phase. Using two loxP sites in a Cis configuration, we generated in vivo cells harboring microdeletions and microduplications for regions of interest covering up to 2.2 Mb. Using this approach in the mouse provides insight into the consequences of segmental aneuploidy for homologous regions of the human chromosome 21 on cell survival. Furthermore, TASCER shows that Cre-induced recombination is more efficient after DNA replication in vivo and provides an opportunity to evaluate, through genetic mosaics, the outcome of copy number variation and segmental aneuploidy in the mouse.
A Novel Chimeric Low-Molecular-Weight Glutenin Subunit Gene From the Wild Relatives of Wheat Aegilops kotschyi and Ae. juvenalis: Evolution at the Glu-3 Loci
Authors: Li Xiaohui , Ma Wujun , Gao Liyan , Zhang Yanzhen , Wang Aili , Ji Kangmin , Wang Ke , Appels Rudi , Yan Yueming
Published: September 2008

Four LMW-m and one novel chimeric (between LMW-i and LMW-m types) low-molecular-weight glutenin subunit (LMW-GS) genes from Aegilops neglecta (UUMM), Ae. kotschyi (UUSS), and Ae. juvenalis (DDMMUU) were isolated and characterized. Sequence structures showed that the 4 LMW-m-type genes, assigned to the M genome of Ae. neglecta, displayed a high homology with those from hexaploid common wheat. The novel chimeric gene, designed as AjkLMW-i, was isolated from both Ae. kotschyi and Ae. juvenalis and shown to be located on the U genome. Phylogentic analysis demonstrated that it had higher identity to the LMW-m-type than the LMW-i-type genes. A total of 20 single nucleotide polymorphisms (SNPs) were detected among the 4 LMW-m genes, with 13 of these being nonsynonymous SNPs that resulted in amino acid substitutions in the deduced mature proteins. Phylogenetic analysis demonstrated that it had higher identity to the LMW-m-type than the LMW-i-type genes. The divergence time estimation showed that the M and D genomes were closely related and diverged at 5.42 million years ago (MYA) while the differentiation between the U and A genomes was 6.82 MYA. We propose that, in addition to homologous recombination, an illegitimate recombination event on the U genome may have occurred 6.38 MYA and resulted in the generation of the chimeric gene AjkLMW-i, which may be an important genetic mechanism for the origin and evolution of LMW-GS Glu-3 alleles as well as other prolamin genes.
Trends in Pediatric and Adult Bicycling Deaths Before and After Passage of a Bicycle Helmet Law
Authors: Wesson David E. , Stephens Derek , Lam Kelvin , Parsons Daria , Spence Laura , Parkin Patricia C.
Published: September 2008

OBJECTIVES. The goals were to examine bicycle-related mortality rates in Ontario, Canada, from 1991 to 2002 among bicyclists 1 to 15 years of age and 16 years of age through adulthood and to determine the effect of legislation (introduced in October 1995 for bicyclists <18 years of age) on mortality rates.

METHODS. The average numbers of deaths per year and mortality rates per 100000 person-years for the prelegislation and postlegislation periods, and the percentage changes, were calculated for each of the 2 age groups (1–15 years and ≥16 years). Differences before and after legislation in the 2 age groups were modeled in a time series analysis.

RESULTS. There were 362 bicycle-related deaths in the 12-year period (1–15 years: 107 deaths; ≥16 years: 255 deaths). For bicyclists 1 to 15 years of age, the average number of deaths per year decreased 52%, the mortality rate per 100000 person-years decreased 55%, and the time series analysis demonstrated a significant reduction in deaths after legislation. The estimated change in the number of deaths per month was −0.59 deaths per month. For bicyclists ≥16 years of age, there were only slight changes in the average number of deaths per year and the mortality rate per 100000 person-years, and the time series analysis demonstrated no significant change in deaths after legislation.

CONCLUSIONS. The bicycle-related mortality rate in children 1 to 15 years of age has decreased significantly, which may be attributable in part to helmet legislation. A similar reduction for bicyclists 16 years of age through adulthood was not identified. These findings support promotion of helmet use, enforcement of the existing law, and extension of the law to adult bicyclists.
Values Parents Apply to Decision-Making Regarding Delivery Room Resuscitation for High-Risk Newborns
Authors: Boss Renee D. , Hutton Nancy , Sulpar Leslie J. , West Anna M. , Donohue Pamela K.
Published: September 2008

OBJECTIVE. The aim of this study was to characterize parental decision-making regarding delivery room resuscitation for infants born extremely prematurely or with potentially lethal congenital anomalies.

METHODS. This was a qualitative multicenter study. We identified English-speaking parents at 3 hospitals whose infants had died as a result of extreme prematurity or lethal congenital anomalies in 1999–2005. Parents were interviewed about their prenatal decision-making. Maternal medical charts were reviewed for documented discussions regarding delivery room resuscitation. Subject enrollment was stopped when saturation of themes was achieved.

RESULTS. Twenty-six mothers of infants were interviewed. All parents wanted to participate to some degree in decisions regarding delivery room resuscitation. Few parents recalled discussing options for delivery room resuscitation with physicians, and even fewer recalled being offered the option of comfort care, even when these discussions were documented in the medical chart. Parents did not report physicians' predictions of morbidity and death to be central to their decision-making. Religion, spirituality, and hope guided decision-making for most parents. Some parents felt that they had not made any decisions regarding resuscitation and instead “left things in God's hands.” These parents typically were documented by staff members to “want everything done.”

CONCLUSIONS. The values that parents find most important during decision-making regarding delivery room resuscitation may not be addressed routinely in prenatal counseling. Parents and physicians may have different interpretations of what is discussed and what decisions are made. Future work should investigate whether physicians can be trained to address effectively parents' values during the decision-making process and whether addressing these values may improve physician-parent communication and lead to better postdecision outcomes for parents.
Occipital Lobe Injury and Cortical Visual Outcomes After Neonatal Hypoglycemia
Authors: Tam Emily W. Y. , Widjaja Elysa , Blaser Susan I. , MacGregor Daune L. , Satodia Prakash , Moore Aideen M.
Published: September 2008

OBJECTIVES. Hypoglycemia is a significant problem in neonates, and a pattern of parietooccipital diffusion restriction on MRI scans has been reported. The purpose of this study was to determine whether hypoglycemic injury, as indicated by diffusion restriction in the occipital lobes, correlated with visual evoked potentials and long-term cortical visual dysfunction.

METHODS. A cohort of 45 neonates from 2000–2005 with diffusion-weighted MRI studies after hypoglycemia was studied retrospectively. Perinatal history and follow-up data were analyzed, and results were correlated with diffusion-weighted imaging findings.The presence of occipital diffusion restriction was assessed qualitatively, and the mean apparent diffusion coefficients of mesial occipital lobes were calculated.

RESULTS. Among 25 patients who underwent diffusion-weighted imaging within 6 days after the onset of hypoglycemia, restricted diffusion in the occipital lobes was found in 8 (50%) of 16 term infants but not in preterm infants. For the remaining 20 patients, who had diffusion-weighted imaging performed >6 days after the initial onset of hypoglycemia, occipital diffusion restriction was not seen, even if hypoglycemia was ongoing. Restricted diffusion was associated with abnormal visual evoked potentials detected within 1 week after birth. Cortical visual deficits were seen in a significant proportion of patients with recurrent hypoglycemia and were correlated significantly with low mesial occipital apparent diffusion coefficient values.

CONCLUSIONS. Diffusion-weighted imaging studies performed within 6 days after initial hypoglycemia were sensitive in term but not preterm neonates. Diffusion restriction, with low apparent diffusion coefficient values, in the mesial occipital poles may indicate the prognosis for visual outcomes in acute settings after neonatal hypoglycemia.
Early Language Outcomes of Early-Identified Infants With Permanent Hearing Loss at 12 to 16 Months of Age
Authors: Vohr Betty , Jodoin-Krauzyk Julie , Tucker Richard , Johnson Mary Jane , Topol Deborah , Ahlgren Marianne
Published: September 2008

OBJECTIVES. The objectives of this study were to determine the early language outcomes of children with mild to profound hearing loss, compared with hearing control children, at 12 to 16 months of age and to examine the effects of “very early” enrollment (≤3 months) in early intervention.

METHODS. This was a prospective longitudinal study of the outcomes of a cohort of 30 infants identified in the Rhode Island universal newborn hearing screening program and 96 hearing control subjects. Eligible families with children with all degrees of congenital hearing loss were invited to enroll. Child language skills were assessed by using the MacArthur-Bates Communicative Development Inventory, Words and Gestures, at 12 to 16 months.

RESULTS. Children with moderate/profound hearing loss had significantly lower numbers of phrases understood, words understood, and early, later, and total gestures, compared with children with mild/minimal hearing loss and hearing control subjects. Furthermore, children with hearing loss who were enrolled in early intervention at ≤3 months had significantly higher percentile scores for number of words understood, words produced, and early, later, and total gestures, compared with those enrolled at >3 months. Regression analyses to test the independent effects on language skills of children with hearing loss identified enrollment in early intervention at ≤3 months as an independent predictor of percentile scores for word and early gesture production.

CONCLUSIONS. Very early enrollment (≤3 months) in early intervention has beneficial effects on early language for children with hearing loss. Nevertheless, 12- to 16-month-old children with moderate/profound hearing loss exhibit delayed receptive and expressive language skills in oral and signed English modes, compared with peers with either mild/minimal hearing loss or typical hearing sensitivity.
Fiber-Tracking Techniques Can Predict the Degree of Neurologic Impairment for Periventricular Leukomalacia
Authors: Murakami Aki , Morimoto Masafumi , Yamada Kei , Kizu Osamu , Nishimura Akira , Nishimura Tsunehiko , Sugimoto Tohru
Published: September 2008

OBJECTIVE. Preterm or low birth weight infants display a greater propensity for white matter injury caused by hypoxic-ischemic encephalopathy in the perinatal period. Such episodes can result in periventricular leukomalacia, which may substantially influence later brain development. Noninvasive methods of assessing the severity of injury at the earliest stage of life have not yet been established.

METHODS. We used diffusion tensor imaging to evaluate sensorimotor fibers in periventricular leukomalacia. Region-of-interest measurements and tractography-based measurements were performed for 10 patients with periventricular leukomalacia. The mean age of the patients was 19 ± 9.5 months (range: 9–41 months). Motor functions were assessed at a mean age of 28 ± 14.5 months.

RESULTS. Measured fractional anisotropy values of the motor tract were significantly higher in all mild periventricular leukomalacia cases than in severe cases. A fractional anisotropy cutoff value of <0.5 was useful for predicting severe periventricular leukomalacia. Region-of-interest measurements were less sensitive, compared with tractography-based measurements.

CONCLUSIONS. Fiber-tracking techniques can provide information on the pathophysiologic features of motor disability in patients with periventricular leukomalacia. Early screening of patients with a history of asphyxia may facilitate early intervention (eg, rehabilitation), to achieve better motor function.
Computer-Based Documentation: Effects on Parent-Provider Communication During Pediatric Health Maintenance Encounters
Authors: Johnson Kevin B. , Serwint Janet R. , Fagan Lawrence A. , Thompson Richard E. , Wilson Modena E. H. , Roter Debra
Published: September 2008

OBJECTIVE. The goal was to investigate the impact of a computer-based documentation tool on parent-health care provider communication during a pediatric health maintenance encounter.

METHODS. We used a quasiexperimental study design to compare communication dynamics between clinicians and parents/children in health maintenance visits before and after implementation of the ClicTate system. Before ClicTate use, paper forms were used to create visit notes. The children examined were ≤18 months of age. All encounters were audiotaped or videotaped. A team of research assistants blinded to group assignment reviewed the audio portion of each encounter. Data from all recordings were analyzed, by using the Roter Interaction Analysis System, for differences in the open/closed question ratio, the extent of information provided by parents and providers, and other aspects of spoken and nonverbal communication (videotaped encounters).

RESULTS. Computer-based documentation visits were slightly longer than control visits (32 vs 27 minutes). With controlling for visit length, the amounts of conversation were similar during control and computer-based documentation visits. Computer-based documentation visits were associated with a greater proportion of open-ended questions (28% vs 21%), more use of partnership strategies, greater proportions of social and positive talk, and a more patient-centered interaction style but fewer orienting and transition phrases.

CONCLUSIONS. The introduction of ClicTate into the health maintenance encounter positively affected several aspects of parent-clinician communication in a pediatric clinic setting. These results support the integration of computer-based documentation into primary care pediatric visits.
First Successful Bone Marrow Transplantation for X-linked Chronic Granulomatous Disease by Using Preimplantation Female Gender Typing and HLA Matching
Authors: Reichenbach Janine , Van de Velde Hilde , De Rycke Martine , Staessen Cathérine , Platteau Peter , Baetens Patricia , Güngör Tayfun , Ozsahin Hulya , Scherer Franziska , Siler Ulrich , Seger Reinhard A. , Liebaers Inge
Published: September 2008

Allogeneic hematopoietic stem cell transplantation from an human leukocyte antigen (HLA)-identical donor is currently the only proven curative treatment for chronic granulomatous disease. Hematopoietic stem cell transplantation with alternative donors is associated with higher morbidity and mortality. Therefore, we performed in vitro fertilization and preimplantation HLA matching combined with female sexing for hematopoietic stem cell transplantation in chronic granulomatous disease. Ethical and psychological issues were considered carefully. We used in vitro fertilization with X-enriched spermatozoa followed by preimplantation genetic diagnosis to identify female HLA-genoidentical embryos in a family in need of a suitable donor for their boy affected with severe X-linked chronic granulomatous disease. Two preimplantation genetic diagnosis cycles were performed in the family. In the second cycle, 2 HLA-genoidentical female embryos were transferred and a singleton pregnancy was obtained, resulting in the birth of an unaffected girl at term. Because of insufficient cell numbers in the cord-blood source, conventional hematopoietic stem cell transplantation had to be performed at 12 months of age of the donor and 5 years of age of the recipient and resulted in complete stable donor chimerism and immunologic reconstitution up to 25 months post–hematopoietic stem cell transplantation. Hematopoietic stem cell transplantation after in vitro fertilization and combined female sexing and HLA matching offers a new and relatively rapid therapeutic option for patients with X-linked primary immunodeficiency such as chronic granulomatous disease who need hematopoietic stem cell transplantation but lack an HLA-genoidentical donor.
Infant Growth and Child Cognition at 3 Years of Age
Authors: Belfort Mandy B. , Rifas-Shiman Sheryl L. , Rich-Edwards Janet W. , Kleinman Ken P. , Oken Emily , Gillman Matthew W.
Published: September 2008

BACKGROUND. Infancy is a critical period for brain development. Few studies have examined the extent to which infant weight gain is associated with later neurodevelopmental outcomes in healthy populations.

OBJECTIVE. The purpose of this work was to examine associations of infant weight gain from birth to 6 months with child cognitive and visual-motor skills at 3 years of age.

PATIENTS AND METHODS. We studied 872 participants in Project Viva, an ongoing prospective, longitudinal, prebirth cohort. We abstracted birth weight from the medical chart and weighed infants at 6 months of age. We used the 2000 Centers for Disease Control and Prevention growth charts to derive weight-for-age z scores. Our primary predictor was infant weight gain, defined as the weight-for-age z score at 6 months adjusted for the weight-for-age z score at birth. At 3 years of age, we measured child cognition with the Peabody Picture Vocabulary Test III and visual-motor skills with the Wide Range Assessment of Visual Motor Abilities.

RESULTS. Mean Peabody Picture Vocabulary Test III score was 104.2, and mean Wide Range Assessment of Visual Motor Abilities test score was 102.8. Mean birth weight z score was 0.21, and mean 6-month weight z score was 0.39. In multiple linear regression adjusted for child age, gender, gestational age, breastfeeding duration, primary language, and race/ethnicity; maternal age, parity, smoking status, and cognition; and parental education and income level, we found no association of infant weight gain with child Peabody Picture Vocabulary Test III score (−0.4 points per z score weight gain increment, 95% confidence interval −1.3, 0.6) or total Wide Range Assessment of Visual Motor Abilities standard score (−0.4 points, 95% confidence interval −1.2, 0.5).

CONCLUSIONS. Slower infant weight gain was not associated with poorer neurodevelopmental outcomes in healthy, term-born 3-year-old children. These results should aid in determining optimal growth patterns in infants to balance risks and benefits of health outcomes through the life course.
Varicella Prevention in the United States: A Review of Successes and Challenges
Authors: Marin Mona , Meissner H. Cody , Seward Jane F.
Published: September 2008

OBJECTIVE. In 1995, the United States was the first country to introduce a universal 1-dose childhood varicella vaccination program. In 2006, the US varicella vaccine policy was changed to a routine 2-dose childhood program, with catchup vaccination for older children. The objective of this review was to summarize the US experience with the 1-dose varicella vaccination program, present the evidence considered for the policy change, and outline future challenges of the program.

METHODS. We conducted a review of publications identified by searching PubMed for the terms “varicella,” “varicella vaccine,” and “herpes zoster.” The search was limited to US publications except for herpes zoster; we reviewed all published literature on herpes zoster incidence.

RESULTS. A single dose of varicella vaccine was 80% to 85% effective in preventing disease of any severity and >95% effective in preventing severe varicella and had an excellent safety profile. The vaccination program reduced disease incidence by 57% to 90%, hospitalizations by 75% to 88%, deaths by >74%, and direct inpatient and outpatient medical expenditures by 74%. The decline of cases plateaued between 2003 and 2006, and outbreaks continued to occur, even among highly vaccinated school populations. Compared with children who received 1 dose, in 1 clinical trial, 2-dose vaccine recipients developed in a larger proportion antibody titers that were more likely to protect against breakthrough disease and had a 3.3-fold lower risk for breakthrough disease and higher vaccine efficacy. Two studies showed no increase in overall herpes zoster incidence, whereas 2 others showed an increase.

CONCLUSIONS. A decade of varicella prevention in the United States has resulted in a dramatic decline in disease; however, even with high vaccination coverage, the effectiveness of 1 dose of vaccine did not generate sufficient population immunity to prevent community transmission. A 2-dose varicella vaccine schedule, therefore, was recommended for children in 2006. Data are inconclusive regarding an effect of the varicella vaccination program on herpes zoster epidemiology.
Understanding the Behavioral and Emotional Consequences of Child Abuse
Authors:   American Academy of Pediatrics, Stirling John ,   and the Committee on Child Abuse and Neglect and Section on Adoption and Foster Care,   American Academy of Child and Adolescent Psychiatry, Amaya-Jackson Lisa ,   National Center for Child Traumatic Stress, Amaya-Jackson Lisa
Published: September 2008

Children who have suffered early abuse or neglect may later present with significant behavior problems including emotional instability, depression, and a tendency to be aggressive or violent with others. Troublesome behaviors may persist long after the abusive or neglectful environment has changed or the child has been in foster care placement. Neurobiological research has shown that early abuse results in an altered physiological response to stressful stimuli, a response that deleteriously affects the child's subsequent socialization. Pediatricians can assist caregivers by helping them recognize the abused or neglected child's altered responses, formulate more effective coping strategies, and mobilize available community resources.
Newly-identified receptors for peptide histidine-isoleucine and GHRH-like peptide in zebrafish help to elucidate the mammalian secretin superfamily
Authors: Wu Sheng , Roch Graeme J , Cervini Laura A , Rivier Jean E , Sherwood Nancy M
Published: August 2008

A group of ten hormones in humans are structurally related and known as the secretin superfamily. These hormones bind to G-protein-coupled receptors that activate the cAMP pathway and are clustered as the secretin or B family. We used an evolutionary approach with zebrafish as a model to understand why some of these hormones, such as peptide histidine-methionine (PHM) and pituitary adenylate cyclase-activating polypeptide (PACAP)-related peptide (PRP) in humans lack a receptor. We used molecular techniques to clone two full-length receptor cDNAs in zebrafish, which were analyzed for amino acid sequence and ligand-binding motifs, phylogenetic position, synteny, tissue expression, functional response, and signaling pathway. Evidence is provided that the two cDNAs encoded the peptide histidine-isoleucine (PHI) receptor and PRP receptor, which is known as GHRH-like peptide (GHRH-LP) receptor in non-mammals. Further, we cloned a zebrafish cDNA encoding the peptides PHI and vasoactive intestinal peptide (VIP). The PHIR had been previously labeled as one type of a VIP–PACAP (VPAC2R) shared receptor based only on sequence data. The PHIR cDNA, transfected into COS7 cells, responded to zebrafish PHI in a sensitive and dose-dependent manner (EC50=1.8×10−9 M) but not to PACAP and VIP. The GHRH-LP receptor responded to both zebrafish GHRH-LP1 and GHRH with a 3.5-fold greater response to the former. For comparison, two zebrafish receptors (PAC1R and VPAC1R) and two human receptors (VPAC2R and GHRHR) were tested with human and/or zebrafish peptides. Unexpectedly, zebrafish VIP activated its PAC1R suggesting that in evolution, PAC1R is not always a specific receptor for PACAP. We conclude that zebrafish, like goldfish, have a specific receptor for PHI and GHRH-LP. Our evidence that zebrafish PHI is more potent than human PHM in activating the human VPAC2R (EC50=7.4×10−9 M) supports our suggestion that the VPAC2R and PHIR shared a common ancestral receptor.
The estrogen receptor α-selective agonist propyl pyrazole triol improves glucose tolerance in ob/ob mice; potential molecular mechanisms
Authors: Lundholm L , Bryzgalova G , Gao H , Portwood N , Fält S , Berndt K D , Dicker A , Galuska D , Zierath J R , Gustafsson J-Å , Efendic S , Dahlman-Wright K , Khan A
Published: August 2008

The aim of this study was to validate the role of estrogen receptor α (ERα) signaling in the regulation of glucose metabolism, and to compare the molecular events upon treatment with the ERα-selective agonist propyl pyrazole triol (PPT) or 17β-estradiol (E2) in ob/ob mice. Female ob/ob mice were treated with PPT, E2 or vehicle for 7 or 30 days. Intraperitoneal glucose and insulin tolerance tests were performed, and insulin secretion was determined from isolated islets. Glucose uptake was assayed in isolated skeletal muscle and adipocytes. Gene expression profiling in the liver was performed using Affymetrix microarrays, and the expression of selected genes was studied by real-time PCR analysis. PPT and E2 treatment improved glucose tolerance and insulin sensitivity. Fasting blood glucose levels decreased after 30 days of PPT and E2 treatment. However, PPT and E2 had no effect on insulin secretion from isolated islets. Basal and insulin-stimulated glucose uptake in skeletal muscle and adipose tissue were similar in PPT and vehicle-treated ob/ob mice. Hepatic lipid content was decreased after E2 treatment. In the liver, treatment with E2 and PPT increased and decreased the respective expression levels of the transcription factor signal transducer and activator of transcription 3, and of glucose-6-phosphatase. In summary, our data demonstrate that PPT exerts anti-diabetic effects, and these effects are mediated via ERα.
PEER TUTORING TO PREVENT FIREARM PLAY: ACQUISITION, GENERALIZATION, AND LONG‐TERM MAINTENANCE OF SAFETY SKILLS
Authors: Jostad Candice M. , Miltenberger Raymond G. , Kelso Pamela , Knudson Peter
Published: September 2008

Hundreds of accidental injuries and deaths to children occur annually in the United States as a result of firearm play. Behavioral skills training (BST) and in situ training have been found to be effective in teaching children the skills to use if they find a firearm, but training requires substantial time and effort. The current study examined the use of peers as tutors as a potential way to decrease the time and resources needed to teach these safety skills to youngsters. Peer trainers conducted BST and in situ training with other children. Children taught by the peer trainers acquired the safety skills and demonstrated them in naturalistic situations in which the skills were needed. Furthermore, all of the peer trainers acquired and maintained the skills. These results support the use of peer tutoring for teaching safety skills to other children.
A PRACTICAL VARIATION OF A MULTIPLE‐SCHEDULE PROCEDURE: BRIEF SCHEDULE‐CORRELATED STIMULI
Authors: Tiger Jeffrey H. , Hanley Gregory P. , Larsen Kylie M.
Published: September 2008

Multiple schedules using continuous discriminative stimuli have been used to minimize children's disruptive requesting for teacher attention (e.g., colored floral leis; Tiger & Hanley, 2004; Tiger, Hanley, & Heal, 2006). The present study evaluated the effectiveness of, and children's preferences for, two multiple‐schedule arrangements in which brief experimenter vocalizations served as discriminative stimuli. Results showed that brief signals were highly effective discriminative stimuli for 3 of the 4 children, and that all children preferred one or both variations of the multiple schedule to a control arrangement. For 1 child, highly discriminated responding was achieved only when continuous signals were introduced.
Improving groundwater level forecasting with a feedforward neural network and linearly regressed projected precipitation
Authors: Tsanis Ioannis K. , Coulibaly Paulin , Daliakopoulos Ioannis N.
Published: September 2008

A module that uses neural networks was developed for forecasting the groundwater changes in an aquifer. A modified standard Feedforward Neural Network (FNN), trained with the Levenberg–Marquardt (LM) algorithm with five input variables (precipitation, temperature, runoff, groundwater level and specific yield) with a deterministic component, is used. The deterministic component links precipitation with the seasonal recharge of the aquifer and projects the seasonal average precipitations. A new algorithm is applied to forecast the groundwater level changes in Messara Valley, Crete, Greece, where groundwater level has been steadily decreasing due to overexploitation during the last 20 years. Results from the new algorithm show that the introduction of specific yield improved the groundwater level forecasting marginally but the linearly projected precipitation component drastically increased the window of forecasting up to 30 months, equivalent to five biannual time-steps.
Joint application of event-based calibration and dynamic identifiability analysis in rainfall–runoff modelling: implications for model parametrisation
Authors: Cullmann Johannes , Wriedt Gunter
Published: September 2008

The goal of this work is to comparatively evaluate the potential of both event-based automatic calibration and Dynamic Identifiability Analysis (DYNIA) as proposed by Wagener et al. This is combined with an investigation on a potential relation of a priori knowledge on event characteristics with optimal model parameters.

A joint application of DYNIA and automatic parameter estimation leads to implications considering the informational content of both methods. Optimal model parameters, identified on an event basis, are tested for statistical relations with physical characteristics of the rainstorm events (e.g. intensity). In this paper, we present results of a modelling study in the Rietholzbach catchment (Switzerland). We employed the hydrological model WaSiM-ETH, using a combined DYNIA (Dynamic Identifiability Analysis) and automatic parameter estimation (PEST) approach to investigate best parameter sets as well as parameter variability along the time series of the hydrograph. The results of the study indicate that the “drainage” parameter identifiability for the long-term simulation is linked to the event-based calibrated parameter for the flood events. However, the parameter sets obtained with single-event calibration could not be fully linked to the chosen characteristic features derived from the precipitation forecast.
Modeling of Gas Hydrate Formation in a High Pressure Reactor
Authors: Mandal Ajay , Laik Sukumar
Published: September 2008

Gas hydrates are now gaining importance in oil and gas industries because they are considered a future source of energy and a means for the transport of natural gas. On the other hand gas hydrates create problems by plugging the pipelines during transportation. Obviously, predicting the conditions in which hydrates are formed would be valuable. In the present study, experiments were performed to observe the conditions, which favor the formation of an ethane gas hydrate. The results of the hydrate formation are elucidated with the help of a conceptual kinetic model. An empirical correlation is developed to predict the rate of formation of the hydrate in terms of the operating and geometric variables of the system. A simple kinetic model based on the dissolved ethane gas is also developed which shows that the hydrate formation follows the first order rate equation.
Evaluation of the Performance of a Three-Phase Fluidized Bed Reactor with Immobilized Yeast Cells for the Biotechnological Production of Xylitol
Authors: Sarrouh Boutros F , da Silva Silvio Silvério
Published: September 2008

This work deals with the evaluation of the hydrodynamic characteristics and fermentation parameters of a bench-scale three-phase fluidized bed reactor (FBR) with cells of the yeast Candida guilliermondii immobilized calcium alginate beads for xylitol production. The effects of the following hydrodynamic variables on cell immobilization were evaluated: total particle density, terminal velocity, particles drag force, minimum fluidization velocity and bed porosity (?). According to the results obtained, the reactor was shown to operate similar to a fixed-bed bioreactor at ? < 0.5 and a fluidized bed bioreactor at ? > 0.5, respectively. The maximum flowrate needed to obtain maximum bed fluidization in the reactor was equal to the terminal velocity of the immobilized cell particles. As for the fermentation parameters, the effects of the aeration rate and fermentation time on the process productivity and yield were analyzed. The maximum xylitol concentration of 28.9 g xylitol/l was obtained at a high aeration rate of 600ml/min after 70h of fermentation, indicating that the use of a high aeration rate in this system is favored for better oxygen transfer into the immobilized cells. The specific xylitol productivity and the xylitol yield were of 0.41 g xylitol/l.h and 0.582 g xylitol/g xylose respectively. After 90h of fermentation xylitol productivity and yield decreased to 0.256 g xylitol/l.h and 0.47 g xylitol/g xylose respectively, indicating the beginning of xylitol consumption by the yeast.
On the Dirac eigenvalues as observables of the on-shell N = 2D = 4 Euclidean supergravity
Authors: Vancea Ion
Published: September 2008

We generalize previous works on the Dirac eigenvalues as dynamical variables of Euclidean gravity and N =1 D = 4 supergravity to on-shell N = 2 D = 4 Euclidean supergravity. The covariant phase space of the theory is defined as the space of the solutions of the equations of motion modulo the on-shell gauge transformations. In this space we define the Poisson brackets and compute their value for the Dirac eigenvalues.
The reformed social sciences to reform the university: mission impossible?
Authors: Greenwood Davydd J. , Levin Morten
Published: September 2008

The core argument is that social science must re-examine its mission and praxis in order to be a significant player in future higher education. This article reviews the results and prospects arising from a four-year international project. Originating in Greenwood and Levin's concern about the social sciences, the project, funded by the Ford Foundation, was organised as an action research network of social scientists. Meeting several times over four years, the assembled group of scholars shifted focus from the future of the social sciences to broader questions of the future of higher education as a whole and the possible role of the social sciences. Four issues emerged as vital future challenges:

• Collective denial among academics that knowledge production (research and teaching) is a collaborative effort and that individual academics depend on and are responsible for contributing to the health of the academic collectivity.

• Academic freedom, conceived as an individual right is under siege and will have to be reconstructed to include both individual rights and collective and institutional responsibilities and rights in higher education.

• An appreciation of the multiplicity of teaching, research and organisational factors that interact to constitute healthy universities is lacking in most quarters.

• Technologies of accountability now drive the development of higher education towards a focus on an artificially narrow metrics of knowledge-generation and away from inquiry into what constitutes relevant and sustainable knowledge-generation practices.
Trends in the use of vagus nerve stimulation for epilepsy: analysis of a nationwide database
Authors: Baaj Ali A. , Benbadis Selim R. , Tatum William O. , Vale Fernando L.
Published: August 2008

Object

Vagus nerve stimulation (VNS) plays a significant role in the treatment of intractable epilepsy. The goal of this study was to analyze trends in the use of VNS for epilepsy in the US by using a nationwide database.

Methods

Data for patients undergoing VNS were obtained from the nationwide inpatient sample for the years 1998–2005. Trends regarding number of procedures, length of stay (LOS), hospital charges, patient sex, and payer information were retrieved and analyzed.

Results

The number of VNS procedures for epilepsy increased between 1998 and 2003 but decreased in the subsequent 2 years. The LOS and hospital charges showed yearly increases. Female patients underwent VNS implantation more than males did, and most procedures were performed in the 18- to 64-year-old age group. The combination of Medicare and Medicaid provided most of the funding for VNS from 2002 through 2005. The VNS procedures were performed mostly in teaching hospitals.

Conclusions

Trends from a national database reveal consistent use of VNS for intractable epilepsy. Greater use of the procedure appears to be reflected in the female population, and the procedure has been performed most often at tertiary care teaching hospitals, where a comprehensive evaluation for all forms of therapy is arguably best able to target appropriate patients for appropriate therapies. With the recent application of VNS to target populations without epilepsy, such as patients with refractory depression, the trend of continued use of this treatment for epilepsy appears likely.
Deep brain stimulation for medically refractory epilepsy
Authors: Ellis Thomas L. , Stevens Andrew
Published: August 2008

Epilepsy is a chronic neurological disorder that affects 0.5–1% of the population. Up to one-third of patients will have incompletely controlled seizures or debilitating side effects of anticonvulsant medications. Although some of these patients may be candidates for resection, many are not. The desire to find alternative treatments for epilepsy has led to a resurgence of interest in the use of deep brain stimulation (DBS), which has been used quite successfully in movement disorders. Small pilot studies and open-label trials have yielded results that may support the use of DBS in selected patients with refractory seizures. Because of the diversity of regions involved with seizure initiation and propagation, a variety of targets for stimulation have been examined. Moreover, stimulation parameters such as amplitude, frequency, pulse duration, and continuous versus intermittent on vary from one study to the next. More studies are necessary to determine if there is an appropriate population of seizure patients for DBS, the optimal target, and the most efficacious stimulation parameters.
Implantation of a responsive neurostimulator device in patients with refractory epilepsy
Authors: Anderson William S. , Kossoff Eric H. , Bergey Gregory K. , Jallo George I.
Published: August 2008

Object

The authors summarize one center's experience with a novel device, the Responsive Neurostimulation (RNS) system, which is used to treat seizures, and they provide technical details regarding the implantation procedure.

Methods

The authors reviewed seizure detection, cortical stimulation, and clinical data obtained in 7 patients in whom the RNS system was implanted. Data pertaining to seizure alteration are provided for the first 4 implant-treated patients. The implantation procedure in the case of one patient with occipital lobe heterotopia is included.

Results

Based on patients' seizure diaries, the implanted devices functioned at a high sensitivity for clinical seizure detection. Reductions in seizure frequency, based on their diaries and on clinic follow-up notes, ranged from 50 to 75%. No adverse stimulation-induced side effects were noted, and no hardware malfunctions requiring explantation occurred. Generator replacements for battery depletion were required at 11, 17, and 20 months in 3 patients. The implantation procedure was well tolerated, and postoperative hospital stays were short. A revision cranioplasty for a skull defect was performed in the index patient, whose case will be discussed in the most detail.

Conclusions

The results obtained in this small preliminary series demonstrate a safe implantation method for the responsive neurostimulation device.
Epilepsy surgery and tuberous sclerosis complex: special considerations
Authors: Bollo Robert J. , Kalhorn Stephen P. , Carlson Chad , Haegeli Veronique , Devinsky Orrin , Weiner Howard L.
Published: August 2008

Epilepsy surgery for medically refractory seizures among patients with tuberous sclerosis complex (TSC) is a well-accepted treatment option. Many epilepsy centers around the world have published their experience over the past several years, supporting the idea that the best seizure control is obtained when a single tuber and associated epileptogenic zone is documented and targeted surgically. Recent advances in imaging and physiological techniques that reveal the epileptogenic zone have been used successfully in children with TSC who are being evaluated for surgery. As a result, a number of different surgical strategies have emerged, each reflecting the experience, strengths, and referral biases of the individual treating teams. Experience suggests that some patients with TSC who present with seizures that are difficult to localize and do not meet the classic selection criteria for epilepsy surgery may, nevertheless, benefit from sugery. Tuberectomy alone is often not sufficient for obtaining seizure control. Intracranial electrode recordings performed in a large number of children with TSC undergoing epilepsy surgery have raised new questions about the relationship of the cortical tuber to the epileptogenic zone in TSC. A careful assessment of the risks and benefits of any surgical strategy, compared with those associated with continued refractory epilepsy, should be considered by the treating team in conjunction with the patient's family. Epilepsy surgery has not only benefited many children with TSC, but it also facilitates the understanding of epileptogenesis in TSC.
Hemispherotomy and other disconnective techniques
Authors: De Ribaupierre Sandrine , Delalande Olivier
Published: August 2008

The surgical treatment of intractable epilepsy has evolved as new technical innovations have been made. Hemispherotomy techniques have been developed to replace hemispherectomy in order to reduce the complication rates while maintaining good seizure control.

Disconnective procedures are based on the interruption of the epileptic network rather than the removal of the epileptogenic zone. They can be applied to hemispheric pathologies, leading to hemispherotomy, but they can also be applied to posterior quadrant epilepsies, or hypothalamic hamartomas.

In this paper, the authors review the literature, present an overview of the historical background, and discuss the different techniques along with their outcomes and complications.
Expanding the role of surgery in intractable extratemporal pediatric epilepsy
Authors: Goyal Monisha , Robinson Shenandoah
Published: August 2008

The aim of epilepsy surgery in children is not only to control seizures but also to curtail future adverse neurological sequelae and improve quality of life. If presurgical evaluation demonstrates discordant or multifocal disease, intracranial surgery may be denied as a viable treatment option. When surgical therapy is offered not just as curative but also as palliative therapy, many children not considered optimal surgical candidates may benefit. From a consecutive series of 57 cases involving children who underwent intracranial epilepsy surgery at Rainbow Babies and Children's Hospital during 2001–2005, the authors present in detail 3 cases involving children who benefited significantly from such an aggressive approach. Marked improvement occurred not only in seizure control, but also in developmental and social functioning.
The role of magnetoencephalography in epilepsy surgery
Authors: Tovar-Spinoza Zulma S. , Ochi Ayako , Rutka James T. , Go Cristina , Otsubo Hiroshi
Published: August 2008

Epilepsy surgery requires the precise localization of the epileptogenic zone and the anatomical localization of eloquent cortex so that these areas can be preserved during cortical resection. Magnetoencephalography (MEG) is a technique that maps interictal magnetic dipole sources onto MR imaging to produce a magnetic source image. Magneto-encephalographic spike sources can be used to localize the epileptogenic zone and be part of the workup of the patient for epilepsy surgery in conjunction with data derived from an analysis of seizure semiology, scalp video electroencephalography, PET, functional MR imaging, and neuropsychological testing. In addition, magnetoencephalographic spike sources can be linked to neuronavigation platforms for use in the neurosurgical field. Finally, paradigms have been developed so that MEG can be used to identify functional areas of the cerebral cortex including the somatosensory, motor, language, and visual evoked fields.

The authors review the basic principles of MEG and the utility of MEG for presurgical planning as well as intra-operative mapping and discuss future applications of MEG technology.