-
Handbook of Clinical Neurology 2020Jean Piaget's theory is a central reference point in the study of normal development in children. He proposed in the 20th century that distinct stages occur in the...
Jean Piaget's theory is a central reference point in the study of normal development in children. He proposed in the 20th century that distinct stages occur in the development of intellectual abilities from the preoperational period (intuitive stage: 4-7 years old) to the second stage of conceptual intelligence. One of the most famous Piagetian tasks is number conservation. Failures and successes in this task reveal two fundamental stages in children's thinking and judgment, shifting at approximately 7 years of age from visuospatial intuition to logico-mathematical operation (i.e., number conservation). New emerging techniques in the 21st century, such as functional magnetic resonance imaging, can support this preeminent theory with an understanding of the cerebral basis of the various stages. Since these new technologies are considered to be invasive in children, such techniques are subject to ethical views and concerns due to pediatric participants. The chapter discusses a brain imaging study on Piaget's conservation-of-number task, showing what can be accomplished through careful ethical considerations in the context of healthy children with normal cognitive development.
Topics: Child; Child Development; Child, Preschool; Cognition; Comprehension; Humans; Judgment; Morals
PubMed: 32958170
DOI: 10.1016/B978-0-444-64150-2.00003-4 -
BMC Genomics Jan 2022The pistil is an essential part of flowers that functions in the differentiation of the sexes and reproduction in plants. The stigma on the pistil can accept pollen to...
BACKGROUND
The pistil is an essential part of flowers that functions in the differentiation of the sexes and reproduction in plants. The stigma on the pistil can accept pollen to allow fertilization and seed development. Papaya (Carica papaya L.) is a dioecious plant, where female flowers exhibit normal pistil, while the male flowers exhibit aborted pistil at a late stage of pistil development.
RESULTS
The developmental stages of papaya pistil were analyzed after first dividing it into slices representing the primordium stage 1 (S1), the pre-meiotic stages S2, post-meiotic stage S3, and the mitotic stage S4. The SS scoring algorithm analysis of genes preferentially expressed at different stages revealed differentially expressed genes between male and female flowers. A transcription factor regulatory network for each stage based on the genes that are differentially expressed between male and female flowers was constructed. Some transcription factors related to pistil development were revealed based on the analysis of regulatory networks such as CpAGL11, CpHEC2, and CpSUPL. Based on the specific expression of genes, constructed a gene regulatory subnetwork with CpAGL11-CpSUPL-CpHEC2 functioning as the core. Analysis of the functionally enriched terms in this network reveals several differentially expressed genes related to auxin/ brassinosteroid signal transduction in the plant hormone signal transduction pathway. At the same time, significant differences in the expression of auxin and brassinosteroid synthesis-related genes between male and female flowers at different developmental stages were detected.
CONCLUSIONS
The pistil abortion of papaya might be caused by the lack of expression or decreased expression of some transcription factors and hormone-related genes, affecting hormone signal transduction or hormone biosynthesis. Analysis of aborted and normally developing pistil in papaya provided new insights into the molecular mechanism of pistil development and sex differentiation in dioecious papaya.
Topics: Carica; Flowers; Gene Expression Regulation, Plant; Plant Growth Regulators; Pollen
PubMed: 34983382
DOI: 10.1186/s12864-021-08197-7 -
Journal of Insect Physiology Mar 2023Phenotypic plasticity in body size is a product of modification of the developmental pathway. Although hatchlings of the desert locust, Schistocerca gregaria, show egg...
Phenotypic plasticity in body size is a product of modification of the developmental pathway. Although hatchlings of the desert locust, Schistocerca gregaria, show egg size-dependent plasticity in body size, it remains unclear how embryogenesis during egg development regulates final embryonic body size. To determine the developmental pathway causing body size variation at hatching, we examined egg and embryonic development at the early, middle, and late egg developmental stages in S. gregaria by comparing small and large eggs. Crowd-reared females produced larger eggs than isolated-reared females. The daily egg developmental rate was similar between small and large eggs: eggs dramatically absorbed external water after days 3 to 7 and nearly doubled the initial egg weight at the late stage of day 12. Morphological measurements of eggs and embryos at different days after oviposition revealed that large eggs were longer than small eggs throughout developmental stages. However, embryo length was similar between small and large eggs at the early stage (anatrepsis). Embryos begin to absorb yolk into their bodies after blastokinesis. The size of large-egg embryos increased significantly from the middle stage (katatrepsis) due to absorption of more yolk than small eggs. Egg length and embryo length were conspicuously larger in large eggs than in small eggs on day 12 of late katatrepsis. These results suggest that egg size did not influence the egg developmental rate and initial embryo size. Large eggs had more yolk and space, resulting in larger final embryos than small eggs. The amount of yolk and size of eggshells during katatrepsis could play a key role in determining hatchling body size in S. gregaria.
Topics: Female; Animals; Grasshoppers; Ovum; Oviposition; Crowding; Body Size; Embryonic Development
PubMed: 36528090
DOI: 10.1016/j.jinsphys.2022.104467 -
Developmental Dynamics : An Official... Jun 2022Ambystoma mexicanum (axolotl) embryos and juveniles have been used as model organisms for developmental and regenerative research for many years. This neotenic aquatic...
Ambystoma mexicanum (axolotl) embryos and juveniles have been used as model organisms for developmental and regenerative research for many years. This neotenic aquatic species maintains the unique capability to regenerate most, if not all, of its tissues well into adulthood. With large externally developing embryos, axolotls were one of the original model species for developmental biology. However, increased access to, and use of, organisms with sequenced and annotated genomes, such as Xenopus laevis and tropicalis and Danio rerio, reduced the prevalence of axolotls as models in embryogenesis studies. Recent sequencing of the large axolotl genome opens up new possibilities for defining the recipes that drive the formation and regeneration of tissues like the limbs and spinal cord. However, to decode the large A. mexicanum genome will take a herculean effort, community resources, and the development of novel techniques. Here, we provide an updated axolotl-staging chart ranging from one-cell stage to immature adult, paired with a perspective on both historical and current axolotl research that spans from their use in early studies of development to the recent cutting-edge research, employment of transgenesis, high-resolution imaging, and study of mechanisms deployed in regeneration.
Topics: Ambystoma mexicanum; Animals; Extremities; Gene Transfer Techniques; Xenopus laevis
PubMed: 35322911
DOI: 10.1002/dvdy.470 -
JMIR MHealth and UHealth May 2021Commercial off-the-shelf activity trackers (eg, Fitbit) allow users to self-monitor their daily physical activity (PA), including the number of steps, type of PA, amount... (Review)
Review
BACKGROUND
Commercial off-the-shelf activity trackers (eg, Fitbit) allow users to self-monitor their daily physical activity (PA), including the number of steps, type of PA, amount of sleep, and other features. Fitbits have been used as both measurement and intervention tools. However, it is not clear how they are being incorporated into PA intervention studies, and their use in specific age groups across the life course is not well understood.
OBJECTIVE
This narrative review aims to characterize how PA intervention studies across the life course use Fitbit devices by synthesizing and summarizing information on device selection, intended use (intervention vs measurement tool), participant wear instructions, rates of adherence to device wear, strategies used to boost adherence, and the complementary use of other PA measures. This review provides intervention scientists with a synthesis of information that may inform future trials involving Fitbit devices.
METHODS
We conducted a search of the Fitabase Fitbit Research Library, a database of studies published between 2012 and 2018. Of the 682 studies available on the Fitabase research library, 60 interventions met the eligibility criteria and were included in this review. A supplemental search in PubMed resulted in the inclusion of 15 additional articles published between 2019 and 2020. A total of 75 articles were reviewed, which represented interventions conducted in childhood; adolescence; and early, middle, and older adulthood.
RESULTS
There was considerable heterogeneity in the use of Fitbit within and between developmental stages. Interventions for adults typically required longer wear periods, whereas studies on children and adolescents tended to have more limited device wear periods. Most studies used developmentally appropriate behavior change techniques and device wear instructions. Regardless of the developmental stage and intended Fitbit use (ie, measurement vs intervention tool), the most common strategies used to enhance wear time included sending participants reminders through texts or emails and asking participants to log their steps or synchronize their Fitbit data daily. The rates of adherence to the wear time criteria were reported using varying metrics. Most studies supplemented the use of Fitbit with additional objective or self-reported measures for PA.
CONCLUSIONS
Overall, the heterogeneity in Fitbit use across PA intervention studies reflects its relative novelty in the field of research. As the use of monitoring devices continues to expand in PA research, the lack of uniformity in study protocols and metrics of reported measures represents a major issue for comparability purposes. There is a need for increased transparency in the prospective registration of PA intervention studies. Researchers need to provide a clear rationale for the use of several PA measures and specify the source of their main PA outcome and how additional measures will be used in the context of Fitbit-based interventions.
Topics: Adolescent; Adult; Aged; Child; Exercise; Fitness Trackers; Humans; Prospective Studies; Sleep; Text Messaging
PubMed: 34047705
DOI: 10.2196/23411 -
Journal of Thermal Biology Dec 2022In a seasonal environment, variation in larval phenotype and developmental plasticity allow crustacean larvae to maximise survival by lengthening or shortening their...
In a seasonal environment, variation in larval phenotype and developmental plasticity allow crustacean larvae to maximise survival by lengthening or shortening their development. The aim of this study is to investigate the effects of temperature, laying season and their interaction on larval developmental pathways (larval instars and larval stages). We monitored the different larval stages and calculated the number of larval instars reached during the development of winter and summer larvae of Palaemon serratus incubated at 12, 16 or 20 °C. We observed a great variability in the larval development (6-13 larval instars and 6 to 11 larval stages). A higher temperature decreases the development time and the number of larval instars. At a given temperature, the development time of winter and summer larvae was not different. Two larval stages were considered supernumerary (zoea 4 and 6), as they were more frequent at low temperatures. At higher temperatures, some larvae started to develop pleopods as early as the third instar, larval stage which had never been described (named here zoea 3'). This phenomenon was more common in winter larvae than in summer larvae. These results provide new insights into the expression of developmental plasticity in decapod larvae.
Topics: Animals; Seasons; Temperature; Palaemonidae; Larva; Cold Temperature
PubMed: 36462878
DOI: 10.1016/j.jtherbio.2022.103343 -
BMC Genomics Oct 2021Alternative splicing (AS) is an important mechanism of posttranscriptional modification and dynamically regulates multiple physiological processes in plants, including...
BACKGROUND
Alternative splicing (AS) is an important mechanism of posttranscriptional modification and dynamically regulates multiple physiological processes in plants, including fruit ripening. However, little is known about alternative splicing during fruit development in fleshy fruits.
RESULTS
We studied the alternative splicing at the immature and ripe stages during fruit development in cucumber, melon, papaya and peach. We found that 14.96-17.48% of multiexon genes exhibited alternative splicing. Intron retention was not always the most frequent event, indicating that the alternative splicing pattern during different developmental process differs. Alternative splicing was significantly more prevalent at the ripe stage than at the immature stage in cucumber and melon, while the opposite trend was shown in papaya and peach, implying that developmental stages adopt different alternative splicing strategies for their specific functions. Some genes involved in fruit ripening underwent stage-specific alternative splicing, indicating that alternative splicing regulates fruits ripening. Conserved alternative splicing events did not appear to be stage-specific. Clustering fruit developmental stages across the four species based on alternative splicing profiles resulted in species-specific clustering, suggesting that diversification of alternative splicing contributes to lineage-specific evolution in fleshy fruits.
CONCLUSIONS
We obtained high quality transcriptomes and alternative splicing events during fruit development across the four species. Dynamics and nonconserved alternative splicing were discovered. The candidate stage-specific AS genes involved in fruit ripening will provide valuable insight into the roles of alternative splicing during the developmental processes of fleshy fruits.
Topics: Alternative Splicing; Fruit; Gene Expression Regulation, Plant; Plants; Prunus persica; Transcriptome
PubMed: 34702184
DOI: 10.1186/s12864-021-08111-1 -
Cell Genomics Jan 2024Gene duplication produces the material that fuels evolutionary innovation. The "out-of-testis" hypothesis suggests that sperm competition creates selective pressure...
Gene duplication produces the material that fuels evolutionary innovation. The "out-of-testis" hypothesis suggests that sperm competition creates selective pressure encouraging the emergence of new genes in male germline, but the somatic expression and function of the newly evolved genes are not well understood. We systematically mapped the expression of young duplicate genes throughout development in Caenorhabditis elegans using both whole-organism and single-cell transcriptomic data. Based on the expression dynamics across developmental stages, young duplicate genes fall into three clusters that are preferentially expressed in early embryos, mid-stage embryos, and late-stage larvae. Early embryonic genes are involved in protein degradation and develop essentiality comparable to the genomic average. In mid-to-late embryos and L4-stage larvae, young genes are enriched in intestine, epidermal cells, coelomocytes, and amphid chemosensory neurons. Their molecular functions and inducible expression indicate potential roles in innate immune response and chemosensory perceptions, which may contribute to adaptation outside of the sperm.
Topics: Animals; Male; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Genes, Duplicate; Semen; Gene Expression Profiling; Larva
PubMed: 38190105
DOI: 10.1016/j.xgen.2023.100467 -
Journal of Visualized Experiments : JoVE Mar 2021The mouse is the mammalian animal model of choice for many human diseases and biological processes. Developmental biology often requires staged-pregnant mice to...
The mouse is the mammalian animal model of choice for many human diseases and biological processes. Developmental biology often requires staged-pregnant mice to determine evolving processes at various timepoints. Moreover, optimal and efficient breeding of model mice requires an assessment of timed pregnancies. Most commonly, mice are mated overnight, and the presence of a vaginal plug is determined; however, the positive predictive value of this technique is suboptimal, and one needs to wait to know if the mouse is truly pregnant. High-resolution ultrasound biomicroscopy is an effective and efficient tool for imaging: 1) Whether a mouse is pregnant; 2) What gestational stage the mouse has reached; and 3) Whether there are intrauterine losses. In addition to the embryos and fetuses, the investigator must also recognize common artifacts in the abdominal cavity so as not to mistake these for a gravid uterus. This article provides a protocol for imaging along with illustrative examples.
Topics: Animals; Female; Humans; Mice; Pregnancy; Ultrasonography
PubMed: 33818561
DOI: 10.3791/61893 -
Humanities & Social Sciences... 2023Employee assistance programs (EAPs) provide work, living, and health services to help employees overcome personal and organizational obstacles that affect their...
Employee assistance programs (EAPs) provide work, living, and health services to help employees overcome personal and organizational obstacles that affect their productivity. Most businesses in Taiwan are small or medium-sized, and their scale, stage of development, and resources affect their implementation of EAPs. This study explored EAPs and related measures that organizations can implement in each stage of their development. The results may serve as a reference for human resources personnel in planning EAPs, specifically in identifying appropriate measures to implement for each developmental stage of their organizations. The modified Delphi method and fuzzy analytic hierarchy process were used to organize and analyze key EAP measures and their weights during the creation, guidance, authorization, coordination, and collaboration stages of organizational development. Data analysis revealed that in all five stages of organizational development, work-related EAP measures are the most crucial. As an organization transitions from the creation to collaboration stages, the work dimension is neglected in favor of the health dimension. In the authorization stage, the organization begins to provide a wider range of services in the living dimension. The results and other information regarding EAP service models indicate that in each developmental stage, an organization should adopt a different EAP service model that suits its resources, organizational structure, implementation of EAP measures, and other factors.
PubMed: 36909258
DOI: 10.1057/s41599-023-01567-4