bluuebunny/crossref_metadata_2025_split huggingface dataset:
Emotion regulation in children with behavior problems: Linking behavioral and brain processes
Authors: Granic Isabela , Meusel Liesel-Ann , Lamm Connie , Woltering Steven , Lewis Marc D. 
Published: July 2012

AbstractPast studies have shown that aggressive children exhibit rigid (rather than flexible) parent–child interactions; these rigid repertoires may provide the context through which children fail to acquire emotion-regulation skills. Difficulties in regulating emotion are associated with minimal activity in dorsal systems in the cerebral cortex, for example, the anterior cingulate cortex. The current study aimed to integrate parent–child and neurocognitive indices of emotion regulation and examine their associations for the first time. Sixty children (8–12 years old) referred for treatment for aggression underwent two assessments. Brain processes related to emotion regulation were assessed using dense-array EEG with a computerized go/no-go task. The N2 amplitudes thought to tap inhibitory control were recorded, and a source analysis was conducted. In the second assessment, parents and children were videotaped while trying to solve a conflict topic. State space grids were used to derive two dynamic flexibility parameters from the coded videotapes: (a) the number of transitions between emotional states and (b) the dispersion of emotional states, based on proportional durations in each state. The regression results showed that flexibility measures were not related to N2 amplitudes. However, flexibility measures were significantly associated with the ratio of dorsal to ventral source activation: for transitions, ΔR2= .27,F(1, 34) = 13.13,p= .001; for dispersion, ΔR2= .29,F(1, 35) = 14.76,p< .001. Thus, in support of our main hypothesis, greater dyadic flexibility was associated with a higher ratio of dorsomedial to ventral activation, suggesting that children with more flexible parent–child interactions are able to recruit relatively more dorsomedial activity in challenging situations.
Paranoid thinking, suspicion, and risk for aggression: A neurodevelopmental perspective
Authors: Tone Erin B. , Davis Jennifer S. 
Published: July 2012

AbstractThis article represents an effort to extend our understanding of paranoia or suspicion and its development by integrating findings across clinical, developmental, and neuroscience literatures. We first define “paranoia” or paranoid thought and examine its prevalence across typically and atypically developing individuals and theoretical perspectives regarding its development and maintenance. We then briefly summarize current ideas regarding the neural correlates of adaptive, appropriately trusting interpersonal perception, social cognition, and behavior across development. Our focus shifts subsequently to examining in normative and atypical developmental contexts the neural correlates of several component cognitive processes thought to contribute to paranoid thinking: (a) attention bias for threat, (b) jumping to conclusions biases, and (c) hostile intent attribution biases. Where possible, we also present data regarding independent links between these cognitive processes and aggressive behavior. By examining data regarding the behavioral and neural correlates of varied cognitive processes that are likely components of a paranoid thinking style, we hope to advance both theoretical and empirical research in this domain.
Reconceptualizing antisocial deviance in neurobehavioral terms
Authors: Patrick Christopher J. , Durbin C. Emily , Moser Jason S. 
Published: July 2012

AbstractWe propose that neuroscientific understanding of antisocial behavior can be advanced by focusing programmatic efforts onneurobehavioral traitconstructs, that is, individual difference constructs with direct referents in neurobiology as well as behavior. As specific examples, we highlight inhibitory control and defensive reactivity as two such constructs with clear relevance for understanding antisocial behavior in the context of development. Variations in inhibitory control are theorized to reflect individual differences in the functioning of brain systems that operate to guide and inhibit behavior and regulate emotional response in the service of nonimmediate goals. Variations in defensive reactivity are posited to reflect individual differences in the sensitivity of the brain's aversive motivational (fear) system. We describe how these constructs have been conceptualized in the adult and child literatures and review work pertaining to traditional psychometric (rating and behaviorally based) assessment of these constructs and their known physiological correlates at differing ages as well as evidence linking these constructs to antisocial behavior problems in children and adults. We outline apsychoneurometricapproach, which entails systematic development of neurobiological measures of target trait constructs through reference to psychological phenotypes, as a paradigm for linking clinical disorders to neurobiological systems. We provide a concrete illustration of this approach in the domain of externalizing proneness and discuss its broader implications for research on conduct disorder, antisocial personality, and psychopathy.
Reduced activity within the dorsal endogenous orienting of attention network to fearful expressions in youth with disruptive behavior disorders and psychopathic traits
Authors: White Stuart F. , Williams W. Craig , Brislin Sarah J. , Sinclair Stephen , Blair Karina S. , Fowler Katherine A. , Pine Daniel S. , Pope Kayla , Blair R. James 
Published: July 2012

AbstractUsing behavioral and blood oxygen level dependent (BOLD) response indices through functional magnetic resonance imaging (fMRI), the current study investigated whether youths with disruptive behavior disorders (conduct disorder and oppositional defiant disorder) plus psychopathic traits (DBD + PT) show aberrant sensitivity to eye gaze information generally and/or whether they show particular insensitivity to eye gaze information in the context of fearful expressions. The participants were 36 children and adolescents (ages 10–17 years); 17 had DBD + PT and 19 were healthy comparison subjects. Participants performed a spatial attention paradigm where spatial attention was cued by eye gaze in faces displaying fearful, angry, or neutral affect. Eye gaze sensitivity was indexed both behaviorally and as BOLD response. There were no group differences in behavioral response: both groups showed significantly faster responses if the target was in the congruent spatial direction indicated by eye gaze. Neither group showed a Congruence × Emotion interaction; neither group showed an advantage from the displayer's emotional expression behaviorally. However, the BOLD response revealed a significant Group × Congruence × Emotion interaction. The comparison youth showed increased activity within the dorsal endogenous orienting network (superior parietal lobule and inferior parietal sulcus) for fearful congruent relative to incongruent trials relative to the youth with DBD + PT. The results are discussed with reference to current models of DBD + PT and possible treatment innovations.
Covert antisocial behavior, peer deviancy training, parenting processes, and sex differences in the development of antisocial behavior during childhood
Authors: Snyder James J. , Schrepferman Lynn P. , Bullard Lisha , McEachern Amber D. , Patterson Gerald R. 
Published: July 2012

AbstractTwo longitudinal studies were used to examine the occurrence and consequences of peer deviancy training during childhood and the relative role of early covert antisocial behavior in risk for antisocial behavior in early adolescence. Peer deviancy training was apparent in a sample of at-risk first grade children, and it showed persistence and increased prevalence across the school year. Peer deviancy training, peer rejection, and unskilled parenting made additive contributions to the development of antisocial behavior during kindergarten and first grade and to antisocial behavior in fourth grade. Skilled parenting partially mitigated the association of peer deviancy training with antisocial behavior for boys. The appearance and growth of covert antisocial behavior was a predictor of fourth grade antisocial for boys and girls, more so than aggressive and overt antisocial behavior. Peer deviancy training and early covert antisocial behavior were key pathways to girls' antisocial behavior in fourth grade, and they complemented the roles of peer rejection and overt antisocial behavior for boys. The relationships of parenting and peer processes to trajectories of antisocial behavior were similar for boys and girls; but boys showed higher levels of antisocial behavior, were more involved in peer deviancy training, and were more likely to experience peer rejection.
The impact of a family-centered intervention on the ecology of adolescent antisocial behavior: Modeling developmental sequelae and trajectories during adolescence
Authors: Van Ryzin Mark J. , Dishion Thomas J. 
Published: July 2012

AbstractThis study used an experimental, longitudinal field trial involving random assignment to the Family Check-Up (FCU) to explore the social ecology of adolescent antisocial behavior. A sample of 998 youths and their families was followed from early to late adolescence (age 12 to 18–19). In the intervention condition, 115 families (23%) elected to receive the FCU. In general, random assignment to the FCU in middle school was associated with reductions in late adolescence antisocial behavior (age 18–19). Variable-centered analyses revealed that the effects were mediated by reductions in family conflict from early to middle adolescence (age 12–15). The link between family conflict and antisocial behavior in turn was mediated by association with deviant peers at age 17; parental monitoring at age 17 was also influential but did not attain the status of a mediator. Person-oriented analyses suggested that the FCU was associated with declining trajectories of family conflict and rising trajectories of parental monitoring but was not associated with trajectories of deviant peer association. A dual-trajectory analysis indicated that the pathways to adolescent antisocial behavior were myriad and varied, suggesting new directions for developmental and intervention research.
Retinol improves in vitro oocyte nuclear maturation under heat stress in heifers
Authors: Maya-Soriano M.J. , Taberner E. , López-Béjar M. 
Published: July 2012

SummaryHeat stress (HS) is especially harmful for bovine ovarian follicle development and oocyte competence. Furthermore, HS causes premature aging in oocytes due to high levels of reactive oxygen species (ROS), involved in the harmful effects over the oocyte maturation and the steroidogenic activity of follicular cells. In this study, the presumptive protective effects of antioxidant agents on heat-stressed oocytes were evaluated. Heifer oocytes were matured for 22 h under control (38°C) and HS conditions (41.5°C at 18–21 h of maturation). For each oocyte, nuclear stage and cortical granule (CG) distribution were evaluated. Steroidogenic activity of cumulus cells was also recorded. The antioxidant agents used in the study were: retinol (1.43 μg/ml), retinyl (0.28 μg/ml) and oleic acid (0.05 mg/ml). Based on a chi-squared test (P < 0.05), HS affected negatively the metaphase II (MII) progression and produced a premature CG exocytosis. Retinol improved the oocyte MII progression. However, retinyl and oleic acid, at the concentrations used in this study, could not counteract adverse effects of HS. A decrease in progesterone and increase in estradiol availability were observed when retinyl and oleic acid were supplemented to the maturation medium, respectively. In conclusion, retinol proved to be valuable in heat-stressed oocytes protecting nuclear maturation.
Do embryonic polar bodies commit suicide?
Authors: Fabian Dušan , Čikoš Štefan , Rehák Pavol , Koppel Juraj 
Published: July 2012

SummaryThe extrusion and elimination of unnecessary gametic/embryonic material is one of the key events that determines the success of further development in all living organisms. Oocytes produce the first polar body to fulfill the maturation process just before ovulation, and release the second polar body immediately after fertilization. The aim of this study was to compile a physiological overview of elimination of polar bodies during early preimplantation development in mice. Our results show that three-quarters of the first polar bodies were lost even at the zygotic stage; the 4-cell stage embryos contained only one (second) polar body, and the elimination of second polar bodies proceeded continuously during later development. Both first and second polar bodies showed several typical features of apoptosis: phosphatidylserine redistribution (observed for the first time in the first polar body), specific DNA degradation, condensed nuclear morphology, and inability to exclude cationic dye from the nucleus during the terminal stage of the apoptotic process. Caspase-3 activity was recorded only in the second polar body. From the morphological point of view, mouse polar bodies acted very similarly to damaged embryonic cells which have lost contact with their neighboring blastomeres. In conclusion, polar bodies possess all the molecular equipment necessary for triggering and executing an active suicide process. Furthermore, similarly as in dying embryonic cells, stressing external conditions (culture in vitro) might accelerate and increase the incidence of apoptotic elimination of the polar bodies in embryos.
Different preferences of IVF and SCNT bovine embryos for culture media
Authors: Xiong Xian-rong , Wang Li-jun , Wang Yong-sheng , Hua Song , Zi Xiang-dong , Zhang Yong 
Published: July 2012

SummaryThe preference of fertilized (IVF) and somatic cell nuclear transfer (SCNT) presumptive zygotes for different media when cultured in vitro to the blastocyst stage was evaluated in this study. The experiment comprised two zygote production methods (IVF and SCNT) × two culture media (mSOF and G1.5/G2.5) factorial design in which culture droplets that contained approximate 30 presumptive zygotes formed the experimental plots for the assessment of cleavage and blastocyst development. There were 15 to 20 replicates (culture droplets) per treatment combination. Sub-samples 30 to 41 of the blastocysts produced were assessed for cell number and cell apoptosis. A further 10 blastocysts per treatment combination were used for quantitative real-time polymerase chain reaction (RT-PCR) to evaluate the relative abundance of Hsp70 and Bax mRNA. Presumptive zygotes produced by IVF were developmentally more competent than SCNT zygotes in terms of cleavage rate (66.9 vs. 57.0%; P < 0.05) and blastocyst development rates (blastocysts of presumptive zygotes 29.7 vs. 24.8%; blastocysts of cleaved zygotes 44.4 vs. 36.6%; P < 0.05). Over both zygote production systems, however, the results were similar whether culture was in mSOF or in G1.5/G2.5 media for cleavage rate (63.2 vs. 62.4%; P > 0.05) and blastocyst development rate (blastocysts of presumptive zygotes 26.4 vs. 25.7%; P > 0.05; blastocysts of cleaved zygotes 41.8 vs. 41.2%; P > 0.05). There was, however, a significant interaction between the method of zygote production and culture medium for the apoptotic index of blastocysts. The interaction was such that IVF-produced zygotes cultured in mSOF had a lower apoptotic index compared with those cultured in G1.5/G2.5 (4.7 ± 1.2% vs. 9.8 ± 0.9%; P < 0.05) whereas SCNT zygotes had a higher apoptotic index when cultured in mSOF compared with those cultured in G1.5/G2.5 (11.9 ± 1.5% vs. 4.5 ± 1.2%; P < 0.05). Moreover, RT-PCR analysis showed that embryos from IVF-produced zygotes cultured in mSOF had a lower expression level of stress-related and apoptosis genes (Hsp70 and Bax) than those cells cultured in G1.5/G2.5 medium, while SCNT-derived embryos cultured in mSOF had a higher expression level of these genes than those embryos cultured in G1.5/G2.5 medium. The results of this study show that bovine IVF- and SCNT-produced presumptive zygotes have different nutrient requirements for in vitro culture to the blastocyst stage of development. IVF-derived zygotes have a preference for mSOF as the culture medium whereas the G1.5/G2.5 medium is more suitable for the culture of bovine SCNT-derived zygotes.
A comprehensive method for the conservation of mouse strains combining natural breeding, sperm cryopreservation and assisted reproductive technology
Authors: Li Dun-Gao , Zhu Yan , Li He-Ping , Chen Xue-Jin , Jiang Man-Xi 
Published: July 2012

SummaryThe maintenance and preservation of strains of mice used in biomedical research presents a unique challenge to individual investigators and research institutions. The goal of this study was to assess a comprehensive system for mouse strain conservation through a combination of natural mating, sperm cryopreservation and assisted reproductive technology. Our strategy was based on the collection and cryopreservation of fresh epididymal sperm from male mice by semi-vasectomy; these mice were then naturally mated for breeding purposes. If no satisfactory results were obtained from natural breeding, then the cryopreserved sperm were used for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI); resultant embryos were then transferred into pseudopregnant-recipient female mice. Our results show that some semi-vasectomized mouse strains can be conserved by natural breeding, and that sterile males can be compensated for through the use of IVF and ICSI technology. As such, we believe this system is suitable for the purpose of strain conservation, allowing the continuation of natural breeding with the safeguard of assisted reproduction available.
Injuries in pacu embryos (Piaractus mesopotamicus) after freezing and thawing
Authors: Neves Patrícia Ribeiro , Ribeiro Ricardo Pereira , Streit Danilo Pedro , Natali Maria Raquel M. , Fornari Darci Carlos , Santos Alexandra Inês , Godoy Leandro C. 
Published: July 2012

SummaryAlthough the sperm cryopreservation of freshwater and marine teleosts has been feasible for years, the cryopreservation of some fish embryos still remains elusive. Thus, the objective of this experiment was to analyze the embryo morphology after freezing and thawing 40 embryos of Piaractus mesopotamicus immersed into methanol and ethylene glycol, both at 7, 10 and 13% plus 0.1 M sucrose for 10 min. Soon after thawing, three embryos were treated with historesin, stained with hematoxylin–eosin and analyzed under an optical microscope. From every treatment, one palette containing embryos was thawed and incubated, but none of the eggs hatched. Samples containing two embryos were immersed into 10% methanol or 10% ethylene glycol both in association with sucrose, and embryos immersed into only water or sucrose solution were frozen, processed and analyzed using scanning electron microscopy (SEM). In both cases, the control group was immersed into only water. Although the embryos had the chorion, vitello, yolk syncytial layer and blastoderm, all of them were found altered under the optical microscope and by SEM. The chorion was irregular and injured; there was no individuality in the yolk granules; the yolk syncytial layer had an irregular shape, thickness and size; the blastoderm showed injuries in the nucleus shape and sometimes was absent; the blastoderm was located in atypical areas and absent in some embryos. In conclusion, no treatment was effective in preserving the embryos, and none of the embryos avoided injury from intracellular ice formation. These morphological injuries during the freezing process made the P. mesopotamicus embryos unfeasible for hatching.
The impact of shadow prices and farmers' impatience on the allocation of a multipurpose renewable resource in Ethiopia
Authors: Teklewold Hailemariam 
Published: July 2012

AbstractIn a mixed farming system in which farmyard manure (FYM) is considered an important multipurpose renewable resource that can be used to enhance soil organic matter, provide additional income and supply household energy, soil fertility depletion could take place within the perspective of the household allocation pattern of FYM. This paper estimates a system of FYM allocation regressions to examine the role of returns to FYM and farmers' impatience on the propensity to allocate FYM to different uses. We parameterize the model using data from a sample of 493 households in Ethiopia. Results indicate a heightened incentive for diverting FYM from farming to marketing for burning outside the household when returns to selling FYM and the farmer's discount rate are high. These reveal the need for policies that will help to reduce farmers' impatience and encourage the substitution of alternative energy sources to increase the use of FYM as a sustainable land management practice.
Market participation, on-farm crop diversity and household welfare: micro-evidence from Kenya
Authors: Asfaw Solomon , Lipper Leslie , Dalton Timothy J. , Audi Patrick 
Published: July 2012

AbstractThis paper examines determinants of output and input market participation. It employs propensity score matching techniques to evaluate the impact of market participation on pigeonpea diversity and household welfare, using cross-sectional data of 333 households from Kenya. Results show that input and output market participation decisions are quite distinct. Output market participation is influenced by household demographics, farm size and radio ownership, while input market participation is determined by farm size, bicycle ownership and access to a salaried income. The findings reveal a positive and significant impact of output market participation on pigeonpea diversity, while input market participation had a negative and significant impact on diversity. The results indicate that output market participants have significantly higher food security status than non-participants, in line with the general findings of the literature. However, no significant impact is found between indicators of household welfare and input market participation.
Brazilian research on extremophiles in the context of astrobiology
Authors: Duarte Rubens T. D. , Nóbrega Felipe , Nakayama Cristina R. , Pellizari Vivian H. 
Published: July 2012

AbstractExtremophiles are organisms adapted to grow at extreme ranges of environmental variables, such as high or low temperatures, acid or alkaline medium, high salt concentration, high pressures and so forth. Most extremophiles are micro-organisms that belong to the Archaea and Bacteria domains, and are widely spread across the world, which include the polar regions, volcanoes, deserts, deep oceanic sediments, hydrothermal vents, hypersaline lakes, acid and alkaline water bodies, and other extreme environments considered hostile to human life. Despite the tropical climate, Brazil has a wide range of ecosystems which include some permanent or seasonally extreme environments. For example, the Cerrado is a biome with very low soil pH with high Al+3concentration, the mangroves in the Brazilian coast are anaerobic and saline, Pantanal has thousands of alkaline–saline lakes, the Caatinga arid and hot soils and the deep sea sediments in the Brazilian ocean shelf. These environments harbour extremophilic organisms that, coupled with the high natural biodiversity in Brazil, could be explored for different purposes. However, only a few projects in Brazil intended to study the extremophiles. In the frame of astrobiology, for example, these organisms could provide important models for defining the limits of life and hypothesize about life outside Earth. Brazilian microbiologists have, however, studied the extremophilic micro-organisms inhabiting non-Brazilian environments, such as the Antarctic continent. The experience and previous results obtained from the Brazilian Antarctic Program (PROANTAR) provide important results that are directly related to astrobiology. This article is a brief synopsis of the Brazilian experience in researching extremophiles, indicating the most important results related to astrobiology and some future perspectives in this area.