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Sample records for discrete developmental stages

  1. Developmental stages of chaetognaths in the coastal environs of Bombay

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, Neelam; Nair, V.R.

    Abundances of developmental stages-juveniles, developing and mature-of Sagitta bedoti, S. oceania, S. enflata and S. robusta were recorded from the coastal, estuarine and creek environs of Bombay (Maharashtra, India) from October 1985 to September...

  2. First developmental stages of advertising in traditional media

    OpenAIRE

    Kesl, Jakub

    2011-01-01

    The first developmental stages of advertising in traditional media Jakub Kesl Abstract Diploma thesis "The first developmental stages of advertising in traditional media" deals with the commercial use of media in its first forms and handles the evolution of advertising communication in conjunction with the development of media. Traditional media - print, radio and television in the period starting with emergence of these media until the point of establishment of advertising as their more or l...

  3. Beyond Discrete Categories: Studying Multiracial, Intersex, and Transgender Children Will Strengthen Basic Developmental Science

    Science.gov (United States)

    Dunham, Yarrow; Olson, Kristina R.

    2016-01-01

    Developmental research on social categorization has overwhelmingly focused on perceptions about and experiences of individuals who are clear or prototypical members of discrete and usually dichotomous social categories. For example, studies of social categorization, stereotyping, prejudice, and social identity have generally explored how children…

  4. Developmental Stages in Receptive Grammar Acquisition: A Processability Theory Account

    Science.gov (United States)

    Buyl, Aafke; Housen, Alex

    2015-01-01

    This study takes a new look at the topic of developmental stages in the second language (L2) acquisition of morphosyntax by analysing receptive learner data, a language mode that has hitherto received very little attention within this strand of research (for a recent and rare study, see Spinner, 2013). Looking at both the receptive and productive…

  5. Optimal developmental stage for vitrification of parthenogenetically activated porcine embryos

    DEFF Research Database (Denmark)

    Li, Rong; Li, Juan; Kragh, Peter

    2012-01-01

    The objective of this experiment was to determine the optimal developmental stage to vitrify in-vitro cultured porcine parthenogenetically activated (PA) embryos. Embryos were vitrified by Cryotop on Day 4, 5 or 6 after oocyte activation (Day 0), and immediately after warming they were either time...

  6. Why Are There Developmental Stages in Language Learning? A Developmental Robotics Model of Language Development.

    Science.gov (United States)

    Morse, Anthony F; Cangelosi, Angelo

    2017-02-01

    Most theories of learning would predict a gradual acquisition and refinement of skills as learning progresses, and while some highlight exponential growth, this fails to explain why natural cognitive development typically progresses in stages. Models that do span multiple developmental stages typically have parameters to "switch" between stages. We argue that by taking an embodied view, the interaction between learning mechanisms, the resulting behavior of the agent, and the opportunities for learning that the environment provides can account for the stage-wise development of cognitive abilities. We summarize work relevant to this hypothesis and suggest two simple mechanisms that account for some developmental transitions: neural readiness focuses on changes in the neural substrate resulting from ongoing learning, and perceptual readiness focuses on the perceptual requirements for learning new tasks. Previous work has demonstrated these mechanisms in replications of a wide variety of infant language experiments, spanning multiple developmental stages. Here we piece this work together as a single model of ongoing learning with no parameter changes at all. The model, an instance of the Epigenetic Robotics Architecture (Morse et al 2010) embodied on the iCub humanoid robot, exhibits ongoing multi-stage development while learning pre-linguistic and then basic language skills. Copyright © 2016 Cognitive Science Society, Inc.

  7. The Developmental Stages of a Community–University Partnership

    Science.gov (United States)

    Allen, Michele L.; Svetaz, María Veronica; Hurtado, G. Ali; Linares, Roxana; Garcia-Huidobro, Diego; Hurtado, Monica

    2013-01-01

    Background: Strong and sustained community–university partnerships are necessary for community-based participatory translational research. Little attention has been paid to understanding the trajectory of research partnerships from a developmental perspective. Objective: To propose a framework describing partnership development and maturation based on Erikson’s eight stages of psychosocial development and describe how our collaboration is moving through those stages. Methods: Collaborators engaged in three rounds of iterative reflection regarding characteristics and contributors to the maturation of the Padres Informados/Jovenes Preparados (Informed Parents/Prepared Youth [PI/JP]) partnership. Lessons Learned: Each stage is characterized by broad developmental partnership tasks. Conflict or tension within the partnership is often a part of achieving the associated tasks. The strengths developed at each stage prepare the partnership for challenges associated with subsequent stages. Conclusions: This framework could provide a means for partnerships to reflect on their strengths and challenges at a given time point, and to help understand why some partnerships fail whereas others achieve maturity. PMID:24056509

  8. Developmental stages of developmental screening: steps to implementation of a successful program.

    Science.gov (United States)

    Pinto-Martin, Jennifer A; Dunkle, Margaret; Earls, Marian; Fliedner, Dane; Landes, Cynthia

    2005-11-01

    Through the use of 2-stage screening strategies, research studies have shown that autism spectrum disorders and other developmental disabilities can now be detected reliably and with greater validity and in children as young as 18 months of age. Screening and diagnostic practices in the medical and educational arena lag far behind clinical research, however, with the average patient age at time of diagnosis being 3 to 6 years.We discuss the challenges of instituting universal developmental screening as part of pediatric care and present 2 models of existing or planned programs of early screening for autism spectrum disorder and developmental disability (1 in a community-based setting and 1 in a pediatric setting), and discuss the pros and cons of the different strategies.

  9. Preliminary analysis of Psoroptes ovis transcriptome in different developmental stages

    Directory of Open Access Journals (Sweden)

    Man-Li He

    2016-11-01

    Full Text Available Abstract Background Psoroptic mange is a chronic, refractory, contagious and infectious disease mainly caused by the mange mite Psoroptes ovis, which can infect horses, sheep, buffaloes, rabbits, other domestic animals, deer, wild camels, foxes, minks, lemurs, alpacas, elks and other wild animals. Features of the disease include intense pruritus and dermatitis, depilation and hyperkeratosis, which ultimately result in emaciation or death caused by secondary bacterial infections. The infestation is usually transmitted by close contact between animals. Psoroptic mange is widespread in the world. In this paper, the transcriptome of P. ovis is described following sequencing and analysis of transcripts from samples of larvae (i.e. the Pso_L group and nymphs and adults (i.e. the Pso_N_A group. The study describes differentially expressed genes (DEGs and genes encoding allergens, which help understanding the biology of P. ovis and lay foundations for the development of vaccine antigens and drug target screening. Methods The transcriptome of P. ovis was assembled and analyzed using bioinformatic tools. The unigenes of P. ovis from each developmental stage and the unigenes differentially between developmental stages were compared with allergen protein sequences contained in the allergen database website to predict potential allergens. Results We identified 38,836 unigenes, whose mean length was 825 bp. On the basis of sequence similarity with seven databases, a total of 17,366 unigenes were annotated. A total of 1,316 DEGs were identified, including 496 upregulated and 820 downregulated in the Pso_L group compared with the Pso_N_A group. We predicted 205 allergens genes in the two developmental stages similar to genes from other mites and ticks, of these, 14 were among the upregulated DEGs and 26 among the downregulated DEGs. Conclusion This study provides a reference transcriptome of P. ovis in absence of a reference genome. The analysis of DEGs and

  10. Cuscuta europaea plastid apparatus in various developmental stages

    Science.gov (United States)

    Švubová, Renáta; Ovečka, Miroslav; Pavlovič, Andrej; Slováková, Ľudmila; Blehová, Alžbeta

    2013-01-01

    It was generally accepted that Cuscuta europaea is mostly adapted to a parasitic lifestyle with no detectable levels of chlorophylls. We found out relatively high level of chlorophylls (Chls a+b) in young developmental stages of dodder. Significant lowering of Chls (a+b) content and increase of carotenoid concentration was typical only for ontogenetically more developed stages. Lower content of photosynthesis-related proteins involved in Chls biosynthesis and in photosystem formation as well as low photochemical activity of PSII indicate that photosynthesis is not the main activity of C. europaea plastids. Previously, it has been shown in other species that the Thylakoid Formation Protein 1 (THF1) is involved in thylakoid membrane differentiation, plant-fungal and plant-bacterial interactions and in sugar signaling with its preferential localization to plastids. Our immunofluorescence localization studies and analyses of haustorial plasma membrane fractions revealed that in addition to plastids, the THF1 protein localizes also to the plasma membrane and plasmodesmata in developing C. europaea haustorium, most abundantly in the digitate cells of the endophyte primordium. These results are supported by western blot analysis, documenting the highest levels of the THF1 protein in “get together” tissues of dodder and tobacco. Based on the fact that photosynthesis is not a typical process in the C. europaea haustorium and on the extra-plastidial localization pattern of the THF1, our data support rather other functions of this protein in the complex relationship between C. europaea and its host. PMID:23438585

  11. Analysing growth and development of plants jointly using developmental growth stages.

    Science.gov (United States)

    Dambreville, Anaëlle; Lauri, Pierre-Éric; Normand, Frédéric; Guédon, Yann

    2015-01-01

    Plant growth, the increase of organ dimensions over time, and development, the change in plant structure, are often studied as two separate processes. However, there is structural and functional evidence that these two processes are strongly related. The aim of this study was to investigate the co-ordination between growth and development using mango trees, which have well-defined developmental stages. Developmental stages, determined in an expert way, and organ sizes, determined from objective measurements, were collected during the vegetative growth and flowering phases of two cultivars of mango, Mangifera indica. For a given cultivar and growth unit type (either vegetative or flowering), a multistage model based on absolute growth rate sequences deduced from the measurements was first built, and then growth stages deduced from the model were compared with developmental stages. Strong matches were obtained between growth stages and developmental stages, leading to a consistent definition of integrative developmental growth stages. The growth stages highlighted growth asynchronisms between two topologically connected organs, namely the vegetative axis and its leaves. Integrative developmental growth stages emphasize that developmental stages are closely related to organ growth rates. The results are discussed in terms of the possible physiological processes underlying these stages, including plant hydraulics, biomechanics and carbohydrate partitioning. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Discrete time population dynamics of a two-stage species with recruitment and capture

    International Nuclear Information System (INIS)

    Ladino, Lilia M.; Mammana, Cristiana; Michetti, Elisabetta; Valverde, Jose C.

    2016-01-01

    This work models and analyzes the dynamics of a two-stage species with recruitment and capture factors. It arises from the discretization of a previous model developed by Ladino and Valverde (2013), which represents a progress in the knowledge of the dynamics of exploited populations. Although the methods used here are related to the study of discrete-time systems and are different from those related to continuous version, the results are similar in both the discrete and the continuous case what confirm the skill in the selection of the factors to design the model. Unlike for the continuous-time case, for the discrete-time one some (non-negative) parametric constraints are derived from the biological significance of the model and become fundamental for the proofs of such results. Finally, numerical simulations show different scenarios of dynamics related to the analytical results which confirm the validity of the model.

  13. Developmental stage of strongyle eggs affects the outcome variations of real-time PCR analysis

    DEFF Research Database (Denmark)

    Andersen, Ulla Vestergaard; Haakansson, I. T.; Roust, Tina

    2013-01-01

    extent developmental stages can affect the variation of diagnostic test results. This study investigated the influence of developmental stages of strongyle eggs on the variation real-time polymerase chain reaction (PCR) results. Mixed species strongyle eggs were obtained from the faeces of a naturally...

  14. Embryonic Stem Cell Culture Conditions Support Distinct States Associated with Different Developmental Stages and Potency

    DEFF Research Database (Denmark)

    Martin Gonzalez, Javier; Morgani, Sophie M; Bone, Robert A

    2016-01-01

    . Conversely, the transcriptome of serum-cultured ESCs correlated with later stages of development (E4.5), at which point embryonic cells are more restricted in their developmental potential. Thus, ESC culture systems are not equivalent, but support cell types that resemble distinct developmental stages. Cells...... derived in one condition can be reprogrammed to another developmental state merely by adaptation to another culture condition....

  15. Morphological markers for microspore developmental stage in maize

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    Ana Paula de Moraes

    2008-10-01

    Full Text Available The use of maize in anther culture has been limited because only few genotypes presented a high androgenetic potential. Obtaining the proper stage of microspore development at culture initiation is one of the most crucial factors for success in the androgenesis. For Brazilian maize genotypes there are no studies reporting a correlation between cytological features and morphological parameters. In this study, morphological parameters were recorded and associated with cytological specific stages of the the microsporogenesis in two Brazilian maize genotypes that were sowed in different places (field and growing chamber. For both genotypes, the plants of the growing chamber presented a delay in development. Spikelets length and anther length/spikelet length ratio are not good parameters since they can be greatly influenced by the environment. The anther length was the more reliable parameter to correlate with a specific developmental stage. Nevertheless, variations between genotypes and environment were detected.A utilização do milho (Zea mays na cultura de anteras é limitada devido ao baixo número de genótipos com alto potencial androgenético. A obtenção de micrósporos no estádio de desenvolvimento apropriado no início da cultura é um dos fatores cruciais para o sucesso do processo androgenético. Em genótipos brasileiros de milho não existem estudos relatando a correlação entre características citológicas e parâmetros morfológicos. Neste estudo, parâmetros morfológicos foram avaliados e associados com estádios específicos da microsporogênese em dois genótipos brasileiros de milho os quais foram semeados em diferentes locais (campo e câmara de crescimento. Para ambos os genótipos, as plantas crescidas na câmara de crescimento apresentaram atraso no desenvolvimento. O comprimento da espigueta e a razão comprimento da antera/comprimento da espigueta não são bons parâmetros uma vez que podem ser muito influenciados

  16. Developmental Stages in School Computer Use: Neither Marx Nor Piaget.

    Science.gov (United States)

    Lengel, James G.

    Karl Marx's theory of stages can be applied to computer use in the schools. The first stage, the P Stage, comprises the entry of the computer into the school. Computer use at this stage is personal and tends to center around one personality. Social studies teachers are seldom among this select few. The second stage of computer use, the D Stage, is…

  17. Developmental stages of an African child and their psychological implications: a comparative study

    OpenAIRE

    2008-01-01

    D. Phil. Human development is a universal phenomenon, characterized by various stages. These stages differ from one culture to the other. Furthermore, each developmental stage tends to bring about expectations that are in accordance with a particular culture. In addition, in each culture there exist problems that are specific to a given stage as well as to the manner in which these problems are resolved. Erikson=s stages of human development are generally regarded as universal. The univers...

  18. Developmental Screening Using the Ages and Stages Questionnaire: Standardized versus Real-World Conditions

    Science.gov (United States)

    San Antonio, Marianne C.; Fenick, Ada M.; Shabanova, Veronika; Leventhal, John M.; Weitzman, Carol C.

    2014-01-01

    Developmental screens are often used in nonstandardized conditions, such as pediatric waiting rooms, despite validation under standardized conditions. We examined the reproducibility of the Ages and Stages Questionnaire (ASQ), a developmental screening instrument commonly used in pediatric practices, under standardized versus nonstandardized…

  19. Violent Victimization and Perpetration during Adolescence: Developmental Stage Dependent Ecological Models

    Science.gov (United States)

    Matjasko, Jennifer L.; Needham, Belinda L.; Grunden, Leslie N.; Farb, Amy Feldman

    2010-01-01

    Using a variant of the ecological-transactional model and developmental theories of delinquency on a nationally representative sample of adolescents, the current study explored the ecological predictors of violent victimization, perpetration, and both for three different developmental stages during adolescence. We examined the relative influence…

  20. SWIMMING BEHAVIOR OF DEVELOPMENTAL STAGES OF THE CALANOID COPEPOD TEMORA-LONGICORNIS AT DIFFERENT FOOD CONCENTRATIONS

    NARCIS (Netherlands)

    VANDUREN, LA; VIDELER, JJ

    1995-01-01

    The swimming behaviour of developmental stages of the marine calanoid copepod Temora longicornis was studied using 2-dimensional observations under a microscope and a 3-dimensional filming technique to analyze swimming mode, swimming speed and swimming trajectories under different food

  1. Developmental rate and behavior of early life stages of bighead carp and silver carp

    Science.gov (United States)

    Chapman, Duane C.; George, Amy E.

    2011-01-01

    The early life stages of Asian carp are well described by Yi and others (1988), but since these descriptions are represented by line drawings based only on live individuals and lacked temperature controls, further information on developmental time and stages is of use to expand understanding of early life stages of these species. Bighead carp and silver carp were cultured under two different temperature treatments to the one-chamber gas bladder stage, and a photographic guide is provided for bighead carp and silver carp embryonic and larval development, including notes about egg morphology and larval swimming behavior. Preliminary information on developmental time and hourly thermal units for each stage is also provided. Both carp species developed faster under warmer conditions. Developmental stages and behaviors are generally consistent with earlier works with the exception that strong vertical swimming immediately after hatching was documented in this report.

  2. Evidence for a conserved microbiota across the different developmental stages of Plodia interpunctella.

    Science.gov (United States)

    Mereghetti, Valeria; Chouaia, Bessem; Limonta, Lidia; Locatelli, Daria Patrizia; Montagna, Matteo

    2017-11-01

    Diversity and composition of lepidopteran microbiotas are poorly investigated, especially across the different developmental stages. To improve this knowledge, we characterize the microbiota among different developmental stages of the Indian meal moth, Plodia interpunctella, which is considered one of the major pest of commodities worldwide. Using culture-independent approach based on Illumina 16S rRNA gene sequencing we characterized the microbiota of four developmental stages: eggs, first-, and last-instar larvae, and adult. A total of 1022 bacterial OTUs were obtained, showing a quite diversified microbiota associated to all the analyzed stages. The microbiotas associated with P. interpunctella resulted almost constant throughout the developmental stages, with approximately 77% of bacterial OTUs belonging to the phylum of Proteobacteria. The dominant bacterial genus is represented by Burkholderia (∼64%), followed by Propionibacterium, Delftia, Pseudomonas, and Stenotrophomonas. A core bacterial community, composed of 139 OTUs, was detected in all the developmental stages, among which 112 OTUs were assigned to the genus Burkholderia. A phylogenetic reconstruction, based on the 16S rRNA, revealed that our Burkholderia OTUs clustered with Burkholderia cepacia complex, in the same group of those isolated from the hemipterans Gossyparia spuria and Acanthococcus aceris. The functional profiling, predicted on the base of the bacterial 16S rRNA, indicates differences in the metabolic pathways related to metabolism of amino acids between preimaginal and adult stages. We can hypothesize that bacteria may support the insect host during preimaginal stages. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  3. Embryonic effects of radiation on ICR mice depending developmental stages

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Yeun Hwa; Kusama, Tomoko; Kai, Michiaki [University of Tokyo, Tokyo (Japan)

    1995-06-15

    The ICR pregnant mice were irradiated at 1.5Gy in every 6 hours in the period of organogenesis in order to classify the stage specificity of the embryonic effects of radiation and the stage of development differentiation of the primordium of each major organ. Intrauterine death, fetal body weight and external malformation in live fetuses were observed on day 18 of gestation. There was no statistically significant difference in the intrauterine mortality at any stage organogenesis. The fetal body weight of the mice irradiated in the intermediate stage of organogenesis showed significantly lower. There were specific highly sensitive stages in the incidences of each external malformation, that is exencephalia, open eyelid, cleft palate, anomalies of extremities and anomalies of the tail. At these stage, the primordial of the major organs are established in ICR mice.

  4. Embryonic effects of radiation on ICR mice depending developmental stages

    International Nuclear Information System (INIS)

    Gu, Yeun Hwa; Kusama, Tomoko; Kai, Michiaki

    1995-01-01

    The ICR pregnant mice were irradiated at 1.5Gy in every 6 hours in the period of organogenesis in order to classify the stage specificity of the embryonic effects of radiation and the stage of development differentiation of the primordium of each major organ. Intrauterine death, fetal body weight and external malformation in live fetuses were observed on day 18 of gestation. There was no statistically significant difference in the intrauterine mortality at any stage organogenesis. The fetal body weight of the mice irradiated in the intermediate stage of organogenesis showed significantly lower. There were specific highly sensitive stages in the incidences of each external malformation, that is exencephalia, open eyelid, cleft palate, anomalies of extremities and anomalies of the tail. At these stage, the primordial of the major organs are established in ICR mice

  5. Personality in the cockroach Diploptera punctata: Evidence for stability across developmental stages despite age effects on boldness

    Science.gov (United States)

    Mettke-Hofmann, Claudia; Preziosi, Richard F.

    2017-01-01

    Despite a recent surge in the popularity of animal personality studies and their wide-ranging associations with various aspects of behavioural ecology, our understanding of the development of personality over ontogeny remains poorly understood. Stability over time is a central tenet of personality; ecological pressures experienced by an individual at different life stages may, however, vary considerably, which may have a significant effect on behavioural traits. Invertebrates often go through numerous discrete developmental stages and therefore provide a useful model for such research. Here we test for both differential consistency and age effects upon behavioural traits in the gregarious cockroach Diploptera punctata by testing the same behavioural traits in both juveniles and adults. In our sample, we find consistency in boldness, exploration and sociality within adults whilst only boldness was consistent in juveniles. Both boldness and exploration measures, representative of risk-taking behaviour, show significant consistency across discrete juvenile and adult stages. Age effects are, however, apparent in our data; juveniles are significantly bolder than adults, most likely due to differences in the ecological requirements of these life stages. Size also affects risk-taking behaviour since smaller adults are both bolder and more highly explorative. Whilst a behavioural syndrome linking boldness and exploration is evident in nymphs, this disappears by the adult stage, where links between other behavioural traits become apparent. Our results therefore indicate that differential consistency in personality can be maintained across life stages despite age effects on its magnitude, with links between some personality traits changing over ontogeny, demonstrating plasticity in behavioural syndromes. PMID:28489864

  6. Personality in the cockroach Diploptera punctata: Evidence for stability across developmental stages despite age effects on boldness.

    Science.gov (United States)

    Stanley, Christina R; Mettke-Hofmann, Claudia; Preziosi, Richard F

    2017-01-01

    Despite a recent surge in the popularity of animal personality studies and their wide-ranging associations with various aspects of behavioural ecology, our understanding of the development of personality over ontogeny remains poorly understood. Stability over time is a central tenet of personality; ecological pressures experienced by an individual at different life stages may, however, vary considerably, which may have a significant effect on behavioural traits. Invertebrates often go through numerous discrete developmental stages and therefore provide a useful model for such research. Here we test for both differential consistency and age effects upon behavioural traits in the gregarious cockroach Diploptera punctata by testing the same behavioural traits in both juveniles and adults. In our sample, we find consistency in boldness, exploration and sociality within adults whilst only boldness was consistent in juveniles. Both boldness and exploration measures, representative of risk-taking behaviour, show significant consistency across discrete juvenile and adult stages. Age effects are, however, apparent in our data; juveniles are significantly bolder than adults, most likely due to differences in the ecological requirements of these life stages. Size also affects risk-taking behaviour since smaller adults are both bolder and more highly explorative. Whilst a behavioural syndrome linking boldness and exploration is evident in nymphs, this disappears by the adult stage, where links between other behavioural traits become apparent. Our results therefore indicate that differential consistency in personality can be maintained across life stages despite age effects on its magnitude, with links between some personality traits changing over ontogeny, demonstrating plasticity in behavioural syndromes.

  7. DEVELOPMENTAL STAGES OF THE EDUCATIONAL STRATEGY OF THE EUROPEAN UNION

    Directory of Open Access Journals (Sweden)

    Olena I. Lokshyna

    2010-09-01

    Full Text Available The article is dedicated to the analysis of the evolution of the educational strategy of EU in the process of its development aimed at the economic stability and security in the region. The author distinguishes key stages of the EU strategy development in the educational area and its present-day concept underlying the importance of correspondence to the requirements of economy and society.

  8. Multiobjective Two-Stage Stochastic Programming Problems with Interval Discrete Random Variables

    Directory of Open Access Journals (Sweden)

    S. K. Barik

    2012-01-01

    Full Text Available Most of the real-life decision-making problems have more than one conflicting and incommensurable objective functions. In this paper, we present a multiobjective two-stage stochastic linear programming problem considering some parameters of the linear constraints as interval type discrete random variables with known probability distribution. Randomness of the discrete intervals are considered for the model parameters. Further, the concepts of best optimum and worst optimum solution are analyzed in two-stage stochastic programming. To solve the stated problem, first we remove the randomness of the problem and formulate an equivalent deterministic linear programming model with multiobjective interval coefficients. Then the deterministic multiobjective model is solved using weighting method, where we apply the solution procedure of interval linear programming technique. We obtain the upper and lower bound of the objective function as the best and the worst value, respectively. It highlights the possible risk involved in the decision-making tool. A numerical example is presented to demonstrate the proposed solution procedure.

  9. Effect of thermal shock on developmental stages of estuarine fish. Final report

    International Nuclear Information System (INIS)

    Dean, J.M.

    1978-12-01

    Physiological data and ecological data show that the few estuarine spawners have a higher thermal tolerance in the embryonic and larval stages than do the freshwater, coastal, or oceanic spawning species. However, since all three groups (freshwater, estuarine, and oceanic spawners) occupy the estuary and coastal waters at different times of the year, knowledge of their physiology and ecology at different developmental or life cycle stages is critical for estuarine management decisions

  10. A transition-constrained discrete hidden Markov model for automatic sleep staging

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    Pan Shing-Tai

    2012-08-01

    Full Text Available Abstract Background Approximately one-third of the human lifespan is spent sleeping. To diagnose sleep problems, all-night polysomnographic (PSG recordings including electroencephalograms (EEGs, electrooculograms (EOGs and electromyograms (EMGs, are usually acquired from the patient and scored by a well-trained expert according to Rechtschaffen & Kales (R&K rules. Visual sleep scoring is a time-consuming and subjective process. Therefore, the development of an automatic sleep scoring method is desirable. Method The EEG, EOG and EMG signals from twenty subjects were measured. In addition to selecting sleep characteristics based on the 1968 R&K rules, features utilized in other research were collected. Thirteen features were utilized including temporal and spectrum analyses of the EEG, EOG and EMG signals, and a total of 158 hours of sleep data were recorded. Ten subjects were used to train the Discrete Hidden Markov Model (DHMM, and the remaining ten were tested by the trained DHMM for recognition. Furthermore, the 2-fold cross validation was performed during this experiment. Results Overall agreement between the expert and the results presented is 85.29%. With the exception of S1, the sensitivities of each stage were more than 81%. The most accurate stage was SWS (94.9%, and the least-accurately classified stage was S1 ( Conclusion The results of the experiments demonstrate that the proposed method significantly enhances the recognition rate when compared with prior studies.

  11. Metabolic profiles and free radical scavenging activity of Cordyceps bassiana fruiting bodies according to developmental stage.

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    Sun-Hee Hyun

    Full Text Available The metabolic profiles of Cordyceps bassiana according to fruiting body developmental stage were investigated using gas chromatography-mass spectrometry. We were able to detect 62 metabolites, including 48 metabolites from 70% methanol extracts and 14 metabolites from 100% n-hexane extracts. These metabolites were classified as alcohols, amino acids, organic acids, phosphoric acids, purine nucleosides and bases, sugars, saturated fatty acids, unsaturated fatty acids, or fatty amides. Significant changes in metabolite levels were found according to developmental stage. Relative levels of amino acids, purine nucleosides, and sugars were higher in development stage 3 than in the other stages. Among the amino acids, valine, isoleucine, lysine, histidine, glutamine, and aspartic acid, which are associated with ABC transporters and aminoacyl-tRNA biosynthesis, also showed higher levels in stage 3 samples. The free radical scavenging activities, which were significantly higher in stage 3 than in the other stages, showed a positive correlation with purine nucleoside metabolites such as adenosine, guanosine, and inosine. These results not only show metabolic profiles, but also suggest the metabolic pathways associated with fruiting body development stages in cultivated C. bassiana.

  12. An analysis of the Athetis lepigone transcriptome from four developmental stages.

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    Li-Tao Li

    Full Text Available Athetis lepigone Möschler (Lepidoptera: Noctuidae has recently become an important insect pest of maize (Zea mays crops in China. In order to understand the characteristics of the different developmental stages of this pest, we used Illumina short-read sequences to perform de novo transcriptome assembly and gene expression analysis for egg, larva, pupa and adult developmental stages. We obtained 10.08 Gb of raw data from Illumina sequencing and recovered 81,356 unigenes longer than 100 bp through a de novo assembly. The total sequence length reached 49.75 Mb with 858 bp of N50 and an average unigene length of 612 bp. Annotation analysis of predicted proteins indicate that 33,736 unigenes (41.47% of total unigenes are matches to genes in the Genbank Nr database. The unigene sequences were subjected to GO, COG and KEGG functional classification. A large number of differentially expressed genes were recovered by pairwise comparison of the four developmental stages. The most dramatic differences in gene expression were found in the transitions from one stage to another stage. Some of these differentially expressed genes are related to cuticle and wing formation as well as the growth and development. We identified more than 2,500 microsatellite markers that may be used for population studies of A. lepigone. This study lays the foundation for further research on population genetics and gene function analysis in A. lepigone.

  13. The developmental stage of strongyle eggs affects the outcome of real-time PCR analysis

    DEFF Research Database (Denmark)

    Roust, Tina; Haakansson, Ida T.; Rhod, Maria

    Several molecular diagnostic tests are based upon measuring and quantifying DNA obtained from parasite eggs. It is well-known that such eggs undergo development during storage, but it remains unknown to which extent the stage of development can affect the diagnostic test result. This project...... investigated whether the developmental stage of strongyle eggs affects real-time polymerase chain reaction (PCR) results. Mixed species strongyle eggs were obtained from the faeces of a naturally infected horse. Eggs were isolated and placed in microtiter plates with demineralised water. A total of 25 wells...... containing 100 eggs each were set up and kept refrigerated for up to five days. Once daily, five wells were microscopied on an inverted microscope, the developmental stages of the eggs were noted, and the eggs harvested for DNA extraction. The protocol was repeated three times. Genomic DNA was extracted...

  14. Detection of perturbation phases and developmental stages in organisms from DNA microarray time series data.

    Directory of Open Access Journals (Sweden)

    Marianne Rooman

    Full Text Available Available DNA microarray time series that record gene expression along the developmental stages of multicellular eukaryotes, or in unicellular organisms subject to external perturbations such as stress and diauxie, are analyzed. By pairwise comparison of the gene expression profiles on the basis of a translation-invariant and scale-invariant distance measure corresponding to least-rectangle regression, it is shown that peaks in the average distance values are noticeable and are localized around specific time points. These points systematically coincide with the transition points between developmental phases or just follow the external perturbations. This approach can thus be used to identify automatically, from microarray time series alone, the presence of external perturbations or the succession of developmental stages in arbitrary cell systems. Moreover, our results show that there is a striking similarity between the gene expression responses to these a priori very different phenomena. In contrast, the cell cycle does not involve a perturbation-like phase, but rather continuous gene expression remodeling. Similar analyses were conducted using three other standard distance measures, showing that the one we introduced was superior. Based on these findings, we set up an adapted clustering method that uses this distance measure and classifies the genes on the basis of their expression profiles within each developmental stage or between perturbation phases.

  15. Correlation between chronological age and third molar developmental stages in an Iranian population (Demirjian method).

    Science.gov (United States)

    Khosronejad, Aria; Navabi, Manijeh; Sakhdari, Shirin; Rakhshan, Vahid

    2017-01-01

    Third molar development is the only available tool for estimating the age of individuals after puberty. Since this tooth has very high interethnic variability, formulas calculated to estimate the age from its development stages cannot be generalized to other populations and should be adjusted for each region. Therefore, this study was conducted to evaluate this method in a sample of Tehran individuals for the first time, and also to compare the development of third molars across sexes and arches, and to estimate cutoff developmental stages for legal minor/major identification. A total of 150 dental patients aged between 15 and 25 years old were prospectively enrolled, and their Demirjian stages were recorded. The associations between chronological age and Demirjian stages were evaluated. Dental formation was compared between sexes and jaws. Cutoff stages were determined to identify legal minor/major cases (above or below 18 years old). Age estimation formula was found for this population. Of the 150 included patients, 56 were males. The difference between the ages of males and females at each given developmental stage was nonsignificant ( P > 0.05), except for the H stage. Age difference between same stage teeth of the maxilla and mandible was nonsignificant. Each of the G and H stages was significantly above 18 years old ( P age were above 90% (all P Third molar development was positively affected by the chronological age ( P = 0.000) and being maxillary ( P = 0.000) but not sex ( P = 0.113). Regression formula for age estimation was: age = 6.52+ (0.64 × sex) + (0.32 × arch) + (1.86 × Demirjian stage). Development of third molar might complete after the age 22. Iranian individuals with third molars at the G and H stages are likely above 18 while those at E and F are likely below 18. Pace of molar development differs for jaws, but intergender differences are open to further investigations.

  16. HUPO BPP pilot study: a proteomics analysis of the mouse brain of different developmental stages.

    Science.gov (United States)

    Wang, Jing; Gu, Yong; Wang, Lihong; Hang, Xingyi; Gao, Yan; Wang, Hangyan; Zhang, Chenggang

    2007-11-01

    This study is a part of the HUPO Brain Proteome Project (BPP) pilot study, which aims at obtaining a reliable database of mouse brain proteome, at the comparison of techniques, laboratories, and approaches as well as at preparing subsequent proteome studies of neurologic diseases. The C57/Bl6 mouse brains of three developmental stages at embryonic day 16 (E16), postnatal day 7 (P7), and 8 wk (P56) (n = 5 in each group) were provided by the HUPO BPP executive committee. The whole brain proteins of each animal were individually prepared using 2-DE coupled with PDQuest software analysis. The protein spots representing developmentally related or stably expressed proteins were then prepared with in-gel digestion followed with MALDI-TOF/TOF MS/MS and analyzed using the MASCOT search engines to search the Swiss-Prot or NCBInr database. The 2-DE gel maps of the mouse brains of all of the developmental stages were obtained and submitted to the Data Collection Centre (DCC). The proteins alpha-enolase, stathmin, actin, C14orf166 homolog, 28,000 kDa heat- and acid-stable phosphoprotein, 3-mercaptopyruvate sulfurtransferase and 40 S ribosomal protein S3a were successfully identified. A further Western blotting analysis demonstrated that enolase is a protein up-regulated in the mouse brain from embryonic stage to adult stage. These data are helpful for understanding the proteome changes in the development of the mouse brain.

  17. The effects of tritiated water on some developmental stages of tilapia nilotica

    International Nuclear Information System (INIS)

    Carino, V.S.

    1986-01-01

    Seven developmental stages of Tilapia nilotica from gastrula (11 hr) to the active feeding and free swimming stage (10-d) were reared in tritiated water of concentrations 10 -3 10 -2 and 10 -1 Ci 1 -1 . The fish were reared for different lengths of time, the first group for the period till the next developmental stage and the second group till 3 weeks of age or day 21. Treated and control specimens were compared. An over-all delay in development was noted both at the gross morphological and the histological levels in the experimental fish. Growth was stunted. Many had unresorped yolk which was observable externally in the distended abdomens and histologically within the liver. Percent survival was lower in the treated fish and this was, in general, inversely related to developmental stage and tritium concentration of the rearing water. Posthatch larvae were sluggish to inactive. The liver exhibited histological aberrations which include the presence of adipose cells in place of liver parenchyma in the more anterior liver regions. Brains of treated fish, in general were smaller. One instance of an abnormal brain growth and findings on the retinal epithelium, spleen and pancreas are described. Development of gonads and digestive tract was, in general, retarded. (Auth.) 40 refs.; 5 tabs

  18. Oocyte transport: Developmental competence of bovine oocytes arrested at germinal vesicle stage by cycloheximide under air.

    Science.gov (United States)

    Hashimoto, Shu; Kimura, Kouji; Iwata, Hisataka; Takakura, Ryo

    2003-02-01

    The effects of the medium (TCM 199 or SOFaa) and temperature (20 or 39 C) during meiotic arrest by cycloheximide (CHX) under air on the developmental competence of bovine oocytes after in vitro maturation (IVM) and fertilization (IVF) were investigated. Oocytes were maintained in meiotic arrest by 10 microg/ml CHX in a 50-microl droplet of 25-mM HEPES-buffered TCM 199 (H199) at 39 C or synthetic oviduct fluid (HSOFaa) at 20 or 39 C in air for 24 h. After release from the arrest, the oocytes was matured and fertilized in vitro and their developmental competence was examined. The developmental rate of oocytes arrested in HSOFaa at 20 C to the blastocyst stage was similar to that of non-arrested oocytes but was significantly higher (Ptransport conditions, we also investigated the meiotic arrest of oocytes maintained in a 0.25-ml straw by CHX individually with 10 microl HSOFaa or as a group (40-50 oocytes) with 170-200 microl HSOFaa at 20 C in air for 24 h. After release from meiotic arrest, the developmental competence of these oocytes was assessed similarly. The developmental rate of oocytes treated with CHX individually was similar to that of those treated with CHX in 50-microl droplet of HSOFaa at 20 C. However, the developmental rate of oocytes treated with CHX as a group was lower than that of oocytes treated with CHX in a 50-microl droplet. Five blastocysts developed from oocytes maintained in meiotic arrest in a plastic straw were transferred to five recipient heifers. Consequently, three recipients became pregnant and 2 calves were delivered. The results of the present study indicate that bovine oocytes treated with CHX in HSOFaa at 20 C under air retain the same developmental competence as non-arrested oocytes.

  19. Action of ethylene, 1-methylcyclopropene and silver thiosulfate in two developmental stages of potted ornamental pepper(

    OpenAIRE

    Paula Cristina Carvalho Lima; Milena Maria Tomaz Oliveira; Wellington Souto Ribeiro; Lucas Cavalcante Costa; Fernando Luiz Finger

    2017-01-01

    The species of Capsicum genus have great genetic variability with enormous potential for marketing as ornamental potted plants. The exposure at ethylene induces various deleterious responses during plants life cycle, but there are few studies on how the ethylene affects early developmental stages of these ornamental plants. Thus, this study aimed to evaluate the effects of the application of ethylene and ethylene inhibitors, 1-methylcyclopropene (1-MCP) and silver thiosulphate (STS) in two ea...

  20. Action of ethylene, 1-methylcyclopropene and silver thiosulfate in two developmental stages of potted ornamental pepper(

    Directory of Open Access Journals (Sweden)

    Paula Cristina Carvalho Lima

    2017-09-01

    Full Text Available The species of Capsicum genus have great genetic variability with enormous potential for marketing as ornamental potted plants. The exposure at ethylene induces various deleterious responses during plants life cycle, but there are few studies on how the ethylene affects early developmental stages of these ornamental plants. Thus, this study aimed to evaluate the effects of the application of ethylene and ethylene inhibitors, 1-methylcyclopropene (1-MCP and silver thiosulphate (STS in two early development stages (seedling or initial flowering of potted ornamental peppers of the cultivars ‘Calypso’ and ‘MG 302’. Cultivar ‘MG 302’ showed intermediate sensitivity to ethylene, while the cultivar ‘Calypso’ showed complete abscission of leaves when exposed to 10 µl of ethylene for 48 hours in both development stages. Plants treated with 1-MCP showed similar durability to control for both varieties and developmental stages, and the treatment with 1-MCP + ethylene was beneficial only for ‘MG 302’. STS was the most efficient substance in delaying the ethylene, wherein at stage 1 there was no leaf abscission and at stage 2 had much reduced leaf abscission occurred, regardless the cultivar. Treatment with STS + ethylene was efficient only at stage 1 for ‘Calypso’ and at stage 2 for ‘MG 302’. According to the data, cultivars showed different levels of sensitivity to ethylene, ‘Calypso’ is very sensitive and ‘MG 302’ showed intermediate sensitivity. Regardless the cultivar, STS treatment significantly blocked the ethylene action in both development stages and the use of 1-MCP was less efficient

  1. Differences in adjustment by child developmental stage among caregivers of children with disorders of sex development

    Science.gov (United States)

    2011-01-01

    Background The current study sought to compare levels of overprotection and parenting stress reported by caregivers of children with disorders of sex development at four different developmental stages. Methods Caregivers (N = 59) of children with disorders of sex development were recruited from specialty clinics and were asked to complete the Parent Protection Scale and Parenting Stress Index/Short Form as measures of overprotective behaviors and parenting stress, respectively. Results Analyses of covariance (ANCOVAs) were conducted to examine differences between caregiver report of overprotection and parenting stress. Results revealed that caregivers of infants and toddlers exhibited more overprotective behaviors than caregivers of children in the other age groups. Further, caregivers of adolescents experienced significantly more parenting stress than caregivers of school-age children, and this effect was driven by personal distress and problematic parent-child interactions, rather than having a difficult child. Conclusions These results suggest that caregivers of children with disorders of sex development may have different psychosocial needs based upon their child's developmental stage and based upon the disorder-related challenges that are most salient at that developmental stage. PMID:22074416

  2. Differences in adjustment by child developmental stage among caregivers of children with disorders of sex development

    Directory of Open Access Journals (Sweden)

    Hullmann Stephanie E

    2011-11-01

    Full Text Available Abstract Background The current study sought to compare levels of overprotection and parenting stress reported by caregivers of children with disorders of sex development at four different developmental stages. Methods Caregivers (N = 59 of children with disorders of sex development were recruited from specialty clinics and were asked to complete the Parent Protection Scale and Parenting Stress Index/Short Form as measures of overprotective behaviors and parenting stress, respectively. Results Analyses of covariance (ANCOVAs were conducted to examine differences between caregiver report of overprotection and parenting stress. Results revealed that caregivers of infants and toddlers exhibited more overprotective behaviors than caregivers of children in the other age groups. Further, caregivers of adolescents experienced significantly more parenting stress than caregivers of school-age children, and this effect was driven by personal distress and problematic parent-child interactions, rather than having a difficult child. Conclusions These results suggest that caregivers of children with disorders of sex development may have different psychosocial needs based upon their child's developmental stage and based upon the disorder-related challenges that are most salient at that developmental stage.

  3. Transcriptome Characterization of Dendrolimus punctatus and Expression Profiles at Different Developmental Stages.

    Directory of Open Access Journals (Sweden)

    Cong-Hui Yang

    Full Text Available The pine moth Dendrolimus punctatus (Walker is a common insect pest that confers serious damage to conifer forests in south of China. Extensive physiology and ecology studies on D. punctatus have been carried out, but the lack of genetic information has limited our understanding of the molecular mechanisms behind its development and resistance. Using RNA-seq approach, we characterized the transcriptome of this pine moth and investigated its developmental expression profiles during egg, larval, pupal, and adult stages. A total of 107.6 million raw reads were generated that were assembled into 70,664 unigenes. More than 30% unigenes were annotated by searching for homology in protein databases. To better understand the process of metamorphosis, we pairwise compared four developmental phases and obtained 17,624 differential expression genes. Functional enrichment analysis of differentially expressed genes showed positive correlation with specific physiological activities of each stage, and these results were confirmed by qRT-PCR experiments. This study provides a valuable genomic resource of D. punctatus covering all its developmental stages, and will promote future studies on biological processes at the molecular level.

  4. The Association of Parent Mindfulness with Parenting and Youth Psychopathology Across Three Developmental Stages.

    Science.gov (United States)

    Parent, Justin; McKee, Laura G; N Rough, Jennifer; Forehand, Rex

    2016-01-01

    The primary purpose of the current study was to test a model examining the process by which parent dispositional mindfulness relates to youth psychopathology through mindful parenting and parenting practices. The universality of the model across youth at three developmental stages was examined: young childhood (3-7 years; n = 210), middle childhood (8-12 years; n = 200), and adolescence (13-17 years; n = 205). Overall, participants were 615 parents (55% female) and one of their 3-to-17 year old children (45% female). Parents reported on their dispositional mindfulness, mindful parenting, positive and negative parenting practices and their child's or adolescent's internalizing and externalizing problems. Consistent findings across all three developmental stages indicated that higher levels of parent dispositional mindfulness were indirectly related to lower levels of youth internalizing and externalizing problems through higher levels of mindful parenting and lower levels of negative parenting practices. Replication of these findings across families with children at different developmental stages lends support to the generalizability of the model.

  5. Influence of Meiotic Stages on Developmental Competence of Goat’ Oocyte After Vitrification

    Science.gov (United States)

    Wahyuningsih, S.; Ihsan, M. N.

    2018-02-01

    This objective of this research was to investigate effect of goat oocyte meiotic stages on developmental competence after cryopreservation. Ovaries were collected from slaugterhouse and oocytes was aspirated from2-6 mm of follicles. Oocyte with compacted cumulus cells and evenly granulated ooplasm were selected for this experiment. The lenght of in vitro maturation before vitrification was 8 or 22 h in IVM media TCM 199 + FCS 10 % + PMSG 10 IU + hCG 10 IU at 38.5 °C in a humidified atmosphere of 5 % CO2 in air and were vitrified. After vitrification process, GVBD and MII oocyte were matured for 18 or 4 h to fullfill 26 h maturation requirement and then oocytes were subjected to IVF and culture. Cleavage and blastocyst formation rate were to asses their developmental competence. Cleavage rates were obtained for both GVBD ( 56.78 %) and MII (69.64 % ) oocytes (PGoat oocytes in different maturation stages response to vitrification differently and MII stages have better developmental competence than GVBD.

  6. Comparative study on developmental stages of the clavicle by postmortem MRI and CT imaging

    DEFF Research Database (Denmark)

    Larsen, Sara Tangmose; Lynnerup, Niels; Jensen, K.E.

    2013-01-01

    Objectives: The developmental stages of the clavicles are important for forensic age estimation purposes in adolescents. This study compares the 4-stage system to evaluate the ossification of the medial end of the clavicle as visualized by magnetic resonance imaging (MRI) and computed tomography...... (CT). As several forensic institutes routinely perform CT scans, the large amount of available data may serve as reference sample for MRI in specific cases. Material and methods: This prospective study included an MRI and CT scan of 47 autopsy cases performed prior to medico-legal autopsy (age range...

  7. The silkworm (Bombyx mori microRNAs and their expressions in multiple developmental stages.

    Directory of Open Access Journals (Sweden)

    Xiaomin Yu

    Full Text Available BACKGROUND: MicroRNAs (miRNAs play crucial roles in various physiological processes through post-transcriptional regulation of gene expressions and are involved in development, metabolism, and many other important molecular mechanisms and cellular processes. The Bombyx mori genome sequence provides opportunities for a thorough survey for miRNAs as well as comparative analyses with other sequenced insect species. METHODOLOGY/PRINCIPAL FINDINGS: We identified 114 non-redundant conserved miRNAs and 148 novel putative miRNAs from the B. mori genome with an elaborate computational protocol. We also sequenced 6,720 clones from 14 developmental stage-specific small RNA libraries in which we identified 35 unique miRNAs containing 21 conserved miRNAs (including 17 predicted miRNAs and 14 novel miRNAs (including 11 predicted novel miRNAs. Among the 114 conserved miRNAs, we found six pairs of clusters evolutionarily conserved cross insect lineages. Our observations on length heterogeneity at 5' and/or 3' ends of nine miRNAs between cloned and predicted sequences, and three mature forms deriving from the same arm of putative pre-miRNAs suggest a mechanism by which miRNAs gain new functions. Analyzing development-related miRNAs expression at 14 developmental stages based on clone-sampling and stem-loop RT PCR, we discovered an unusual abundance of 33 sequences representing 12 different miRNAs and sharply fluctuated expression of miRNAs at larva-molting stage. The potential functions of several stage-biased miRNAs were also analyzed in combination with predicted target genes and silkworm's phenotypic traits; our results indicated that miRNAs may play key regulatory roles in specific developmental stages in the silkworm, such as ecdysis. CONCLUSIONS/SIGNIFICANCE: Taking a combined approach, we identified 118 conserved miRNAs and 151 novel miRNA candidates from the B. mori genome sequence. Our expression analyses by sampling miRNAs and real-time PCR over

  8. Comparative transcriptome analysis of two races of Heterodera glycines at different developmental stages.

    Directory of Open Access Journals (Sweden)

    Gaofeng Wang

    Full Text Available The soybean cyst nematode, Heterodera glycines, is an important pest of soybeans. Although resistance is available against this nematode, selection for virulent races can occur, allowing the nematode to overcome the resistance of cultivars. There are abundant field populations, however, little is known about their genetic diversity. In order to elucidate the differences between races, we investigated the transcriptional diversity within race 3 and race 4 inbred lines during their compatible interactions with the soybean host Zhonghuang 13. Six different race-enriched cDNA libraries were constructed with limited nematode samples collected from the three sedentary stages, parasitic J2, J3 and J4 female, respectively. Among 689 putative race-enriched genes isolated from the six libraries with functional annotations, 92 were validated by quantitative RT-PCR (qRT-PCR, including eight putative effector encoding genes. Further race-enriched genes were validated within race 3 and race 4 during development in soybean roots. Gene Ontology (GO analysis of all the race-enriched genes at J3 and J4 female stages showed that most of them functioned in metabolic processes. Relative transcript level analysis of 13 selected race-enriched genes at four developmental stages showed that the differences in their expression abundance took place at either one or more developmental stages. This is the first investigation into the transcript diversity of H. glycines races throughout their sedentary stages, increasing the understanding of the genetic diversity of H. glycines.

  9. Effects of copper on early developmental stages of Lessonia nigrescens Bory (Phaeophyceae)

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, Loretto [Departamento de Ecologia, Center for Advanced Studies in Ecology and Biodiversity, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Post-code 6513677, Alameda 340, Santiago (Chile); Medina, Matias H. [Departamento de Ecologia, Center for Advanced Studies in Ecology and Biodiversity, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Post-code 6513677, Alameda 340, Santiago (Chile); CIIMAR - Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratory of Ecotoxicology, Universidade do Porto (Portugal); Andrade, Santiago [Departamento de Ecologia, Center for Advanced Studies in Ecology and Biodiversity, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Post-code 6513677, Alameda 340, Santiago (Chile); Oppliger, Valeria [Departamento de Ecologia, Center for Advanced Studies in Ecology and Biodiversity, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Post-code 6513677, Alameda 340, Santiago (Chile); Correa, Juan A. [Departamento de Ecologia, Center for Advanced Studies in Ecology and Biodiversity, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Post-code 6513677, Alameda 340, Santiago (Chile)]. E-mail: jcorrea@bio.puc.cl

    2007-01-15

    Copper effects on the early developmental gametophytic and sporophytic stages of the kelp Lessonia nigrescens were tested in gradients of increasing concentrations of ASV-labile copper. The results demonstrated a high sensitivity to copper of all life-history stages of the alga, where even the lowest tested concentration affected spore release as well as their subsequent settlement. More significant, concentrations higher than 7.87 {mu}g L{sup -1} totally interrupted the development of the spores after they settle. This effect led to a failure in the formation of male and female gametophytes and, as a consequence, to a complete disruption of the normal life cycle of the kelp. Thus, we suggest that the absence of L. nigrescens from copper-enriched environments results from the high sensitivity of its early life cycle stages, which limits growth and maturation of the gametophytic microscopic phase and, as a consequence, prevents development of the macroscopic sporophytic phase. - Early developmental stages of Lessonia nigrescens are highly sensitive to copper.

  10. Initiation and developmental stages of steel corrosion in wet H2S environments

    International Nuclear Information System (INIS)

    Bai, Pengpeng; Zhao, Hui; Zheng, Shuqi; Chen, Changfeng

    2015-01-01

    Highlights: • The initiation and development stages of steel corrosion in wet H 2 S environment were investigated. • Preferential dissolution at the grain boundaries of steel allowed corrosion products to form and accumulate. • The shapes and crystal types of corrosion products at various steel layers differed. • With increasing duration time, the S 2− peak with a binding energy of 161.2 eV gradually decreased. • A model of the formation process of corrosion product films was proposed. - Abstract: The initiation and various developmental stages of steel corrosion in H 2 S environments were investigated using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Results revealed that grain boundaries corrode at the initiation stage and that corrosion products initially form on both sides of the grain boundary and then accumulate. Corrosion products grew at the interface between the steel and corrosion product layer at the developmental stage. XPS analyses showed the composition and valence states of the corrosion products, and a model of the formation process of corrosion product films was proposed

  11. Effects of copper on early developmental stages of Lessonia nigrescens Bory (Phaeophyceae)

    International Nuclear Information System (INIS)

    Contreras, Loretto; Medina, Matias H.; Andrade, Santiago; Oppliger, Valeria; Correa, Juan A.

    2007-01-01

    Copper effects on the early developmental gametophytic and sporophytic stages of the kelp Lessonia nigrescens were tested in gradients of increasing concentrations of ASV-labile copper. The results demonstrated a high sensitivity to copper of all life-history stages of the alga, where even the lowest tested concentration affected spore release as well as their subsequent settlement. More significant, concentrations higher than 7.87 μg L -1 totally interrupted the development of the spores after they settle. This effect led to a failure in the formation of male and female gametophytes and, as a consequence, to a complete disruption of the normal life cycle of the kelp. Thus, we suggest that the absence of L. nigrescens from copper-enriched environments results from the high sensitivity of its early life cycle stages, which limits growth and maturation of the gametophytic microscopic phase and, as a consequence, prevents development of the macroscopic sporophytic phase. - Early developmental stages of Lessonia nigrescens are highly sensitive to copper

  12. Bacterial communities associated with white shrimp (Litopenaeus vannamei larvae at early developmental stages

    Directory of Open Access Journals (Sweden)

    ANTONIUS SUWANTO

    2010-04-01

    Full Text Available Bacterial communities associated with white shrimp (Litopenaeus vannamei larvae at early developmental stages. Biodiversitas 11 (2: 65-68.Terminal Restriction Fragment Length Polymorphism (T-RFLP was used to monitor the dynamics of the bacterial communities associated with early developmental stages of white shrimp (Litopenaeus vannamei larvae. Samples for analysis were egg, hatching nauplii, 24 hours old nauplii, and 48 hours old nauplii which were collected from one cycle of production at commercial hatchery. T-RFLP results indicated that the bacterial community associated with early stages of shrimp development might be transferred vertically from broodstock via egg. There was no significant difference between bacterial communities investigated, except the bacterial community of 48 hours old nauplii. Diversity analyses showed that the bacterial community of egg had the highest diversity and evenness, meanwhile the bacterial community of 48 hours old nauplii had the lowest diversity. Nine phylotypes were found at all stages with high abundance. Those TRFs were identified as γ- proteobacteria, α-proteobacteria, and bacteroidetes group.

  13. Characterization of Adelphocoris suturalis (Hemiptera: Miridae) Transcriptome from Different Developmental Stages

    Science.gov (United States)

    Tian, Caihong; Tek Tay, Wee; Feng, Hongqiang; Wang, Ying; Hu, Yongmin; Li, Guoping

    2015-06-01

    Adelphocoris suturalis is one of the most serious pest insects of Bt cotton in China, however its molecular genetics, biochemistry and physiology are poorly understood. We used high throughput sequencing platform to perform de novo transcriptome assembly and gene expression analyses across different developmental stages (eggs, 2nd and 5th instar nymphs, female and male adults). We obtained 20 GB of clean data and revealed 88,614 unigenes, including 23,830 clusters and 64,784 singletons. These unigene sequences were annotated and classified by Gene Ontology, Clusters of Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes databases. A large number of differentially expressed genes were discovered through pairwise comparisons between these developmental stages. Gene expression profiles were dramatically different between life stage transitions, with some of these most differentially expressed genes being associated with sex difference, metabolism and development. Quantitative real-time PCR results confirm deep-sequencing findings based on relative expression levels of nine randomly selected genes. Furthermore, over 791,390 single nucleotide polymorphisms and 2,682 potential simple sequence repeats were identified. Our study provided comprehensive transcriptional gene expression information for A. suturalis that will form the basis to better understanding of development pathways, hormone biosynthesis, sex differences and wing formation in mirid bugs.

  14. Flower structure and developmental stages of the capitulum of Smallanthus sonchifolius (Asteraceae): reproductive implications.

    Science.gov (United States)

    Ibañez, M S; Mercado, M I; Coll Aráoz, M V; Zannier, M L; Grau, A; Ponessa, G I

    2017-03-01

    Yacon (Smallanthus sonchifolius, Asteraceae) is an ancient andean crop that has numerous dietary and medicinal properties. Morphological and anatomical features and developmental changes of the capitulum were studied. A ray floret is a pistillate, female flower, while a disc floret is a staminate male flower, and the former opens before the latter, being pseudanthium protogynous. The capitulum presents interesting attributes for pollinators such as flower structure, nectaries and pollenkitt. Gynoecial nectaries were found on undeveloped ovary in the disc floret, but not in the ray floret. Glandular trichomes were observed on the abaxial epidermis of corolla in the ray floret, but not in the disc floret. Capitulum development was divided into eight stages. Stigma receptivity varied with these stages. Pollen viability was low (15%). In accordance with low viability, pollen grains exhibit diverse sizes and shapes, reduction in length of spines, and abnormal protoplasm. Examination of ovary development in the ray floret showed that a mature ovule was formed, but fertilization did not occur. In advanced developmental stages, the capitulum showed proliferation of the endothelium, degeneration of the embryo sac, and all harvested cypselae had aborted seeds. Problems found in pollen viability and aborted cypselae could be the result of a history of vegetative propagation in the domestication process.

  15. An adaptive three-stage extended Kalman filter for nonlinear discrete-time system in presence of unknown inputs.

    Science.gov (United States)

    Xiao, Mengli; Zhang, Yongbo; Wang, Zhihua; Fu, Huimin

    2018-04-01

    Considering the performances of conventional Kalman filter may seriously degrade when it suffers stochastic faults and unknown input, which is very common in engineering problems, a new type of adaptive three-stage extended Kalman filter (AThSEKF) is proposed to solve state and fault estimation in nonlinear discrete-time system under these conditions. The three-stage UV transformation and adaptive forgetting factor are introduced for derivation, and by comparing with the adaptive augmented state extended Kalman filter, it is proven to be uniformly asymptotically stable. Furthermore, the adaptive three-stage extended Kalman filter is applied to a two-dimensional radar tracking scenario to illustrate the effect, and the performance is compared with that of conventional three stage extended Kalman filter (ThSEKF) and the adaptive two-stage extended Kalman filter (ATEKF). The results show that the adaptive three-stage extended Kalman filter is more effective than these two filters when facing the nonlinear discrete-time systems with information of unknown inputs not perfectly known. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Adolescents with Developmental Dyscalculia Do Not Have a Generalized Magnitude Deficit – Processing of Discrete and Continuous Magnitudes

    Science.gov (United States)

    McCaskey, Ursina; von Aster, Michael; O’Gorman Tuura, Ruth; Kucian, Karin

    2017-01-01

    The link between number and space has been discussed in the literature for some time, resulting in the theory that number, space and time might be part of a generalized magnitude system. To date, several behavioral and neuroimaging findings support the notion of a generalized magnitude system, although contradictory results showing a partial overlap or separate magnitude systems are also found. The possible existence of a generalized magnitude processing area leads to the question how individuals with developmental dyscalculia (DD), known for deficits in numerical-arithmetical abilities, process magnitudes. By means of neuropsychological tests and functional magnetic resonance imaging (fMRI) we aimed to examine the relationship between number and space in typical and atypical development. Participants were 16 adolescents with DD (14.1 years) and 14 typically developing (TD) peers (13.8 years). In the fMRI paradigm participants had to perform discrete (arrays of dots) and continuous magnitude (angles) comparisons as well as a mental rotation task. In the neuropsychological tests, adolescents with dyscalculia performed significantly worse in numerical and complex visuo-spatial tasks. However, they showed similar results to TD peers when making discrete and continuous magnitude decisions during the neuropsychological tests and the fMRI paradigm. A conjunction analysis of the fMRI data revealed commonly activated higher order visual (inferior and middle occipital gyrus) and parietal (inferior and superior parietal lobe) magnitude areas for the discrete and continuous magnitude tasks. Moreover, no differences were found when contrasting both magnitude processing conditions, favoring the possibility of a generalized magnitude system. Group comparisons further revealed that dyscalculic subjects showed increased activation in domain general regions, whilst TD peers activate domain specific areas to a greater extent. In conclusion, our results point to the existence of a

  17. Adolescents with Developmental Dyscalculia Do Not Have a Generalized Magnitude Deficit - Processing of Discrete and Continuous Magnitudes.

    Science.gov (United States)

    McCaskey, Ursina; von Aster, Michael; O'Gorman Tuura, Ruth; Kucian, Karin

    2017-01-01

    The link between number and space has been discussed in the literature for some time, resulting in the theory that number, space and time might be part of a generalized magnitude system. To date, several behavioral and neuroimaging findings support the notion of a generalized magnitude system, although contradictory results showing a partial overlap or separate magnitude systems are also found. The possible existence of a generalized magnitude processing area leads to the question how individuals with developmental dyscalculia (DD), known for deficits in numerical-arithmetical abilities, process magnitudes. By means of neuropsychological tests and functional magnetic resonance imaging (fMRI) we aimed to examine the relationship between number and space in typical and atypical development. Participants were 16 adolescents with DD (14.1 years) and 14 typically developing (TD) peers (13.8 years). In the fMRI paradigm participants had to perform discrete (arrays of dots) and continuous magnitude (angles) comparisons as well as a mental rotation task. In the neuropsychological tests, adolescents with dyscalculia performed significantly worse in numerical and complex visuo-spatial tasks. However, they showed similar results to TD peers when making discrete and continuous magnitude decisions during the neuropsychological tests and the fMRI paradigm. A conjunction analysis of the fMRI data revealed commonly activated higher order visual (inferior and middle occipital gyrus) and parietal (inferior and superior parietal lobe) magnitude areas for the discrete and continuous magnitude tasks. Moreover, no differences were found when contrasting both magnitude processing conditions, favoring the possibility of a generalized magnitude system. Group comparisons further revealed that dyscalculic subjects showed increased activation in domain general regions, whilst TD peers activate domain specific areas to a greater extent. In conclusion, our results point to the existence of a

  18. Endoreduplication intensity as a marker of seed developmental stage in the Fabaceae.

    Science.gov (United States)

    Rewers, Monika; Sliwinska, Elwira

    2012-12-01

    Flow cytometry (FCM) can be used to study cell cycle activity in developing, mature and germinating seeds. It provides information about a seed's physiological state and therefore can be used by seed growers for assessing optimal harvest times and presowing treatments. Because an augmented proportion of 4C nuclei usually is indicative of high mitotic activity, the 4C/2C ratio is commonly used to follow the progress of seed development and germination. However, its usefulness for polysomatic (i.e., containing cells with different DNA content) seeds is questioned. Changes in cell cycle/endoreduplication activity in developing seeds of five members of the Fabaceae were studied to determine a more suitable marker of seed developmental stages for polysomatic species based on FCM measurements. Seeds of Phaseolus vulgaris, Medicago sativa, Pisum sativum, Vicia sativa, and Vicia faba var. minor were collected 20, 30, 40, 50, and 60 days after flowering (DAF), embryos were isolated and the proportion of nuclei with different DNA contents in the embryo axis and cotyledon was established. The ratios 4C/2C and (Σ>2C)/2C were calculated. Dried seeds were subjected to laboratory germination tests following international seed testing association (ISTA) rules. Additionally, the absolute nuclear DNA content was estimated in the leaves of the studied species. During seed development nuclei with DNA contents from 2C to 128C were detected; the endopolyploidy pattern depended on the species, seed organ and developmental stage. The cell cycle/endoreduplication parameters correlated negatively with genome size. The (Σ>2C)/2C ratio in the cotyledons reflected the seed developmental stage and corresponded with seed germinability. Therefore, this ratio is recommended as a marker in polysomatic seed research and production instead of the 4C/2C ratio, which does not consider the occurrence of endopolyploid cells. Copyright © 2012 International Society for Advancement of Cytometry.

  19. Molecular investigations of Hepatozoon species in dogs and developmental stages of Rhipicephalus sanguineus.

    Science.gov (United States)

    Aktas, Munir; Ozübek, Sezayi; Ipek, Duygu Neval Sayın

    2013-06-01

    The occurrence and distribution of Hepatozoon species in stray dogs, and the developmental stages of Rhipicephalus sanguineus detached from the same dogs in Diyarbakır Province, Turkey is reported. A total of 328 ticks, including 133 adults (55 males and 75 females consist of 63 partially engorged and 15 fully engorged) and 195 nymphs (91 partially engorged and 104 fully engorged) were detached from the dogs. Fully engorged nymphs and females were incubated at 27 °C and relative humidity of 85 % to molt to adult stage and recover eggs. The ticks were pooled according to sex and developmental stage. No Hepatozoon gamonts were found, whereas, by PCR, 15.87 % (10/63) of the dogs were infected with Hepatozoon canis. Of the 68 tick pools tested, 14 (20.58 %) pools were infected with Hepatozoon spp., an overall maximum likelihood estimation of prevalence of 4.9 % (95 % confidence intervals (CI) = 2.85-7.93 %) per 100 ticks. Maximum likelihood estimation of the infection rate varied by tick sex and developmental categories, ranging from 1.75 % (95 % CI = 0.11-8.11 %) in fed males to 6.81 % (95 % CI = 2.07-17.46 %) in unfed females. One amplicon from a fed adult female was 99 % identical to the sequence for Hepatozoon felis. The remaining sequences isolated from both dogs and ticks shared 99-100 % similarity with the corresponding H. canis isolates. This is the first detection of H. canis and H. felis in the tick R. sanguineus in Turkey.

  20. Relationships among developmental stage, metamorphic timing, and concentrations of elements in bullfrogs (Rana catesbeiana)

    Energy Technology Data Exchange (ETDEWEB)

    Snodgrass, J.W.; Hopkins, W.A.; Roe, J.H. [Towson University, Towson, MD (United States). Dept. for Biological Science

    2003-07-01

    We collected bullfrog (Rana catesbeiana) larvae from a coal combustion waste settling basin to investigate the effects of developmental stage and timing of metamorphosis on concentrations of a series of trace elements in bullfrog tissues. Bullfrogs at four stages of development (from no hind limbs to recently metamorphosed juveniles) and bullfrogs that metamorphosed in the fall or overwintered in the contaminated basin and metamorphosed in the spring were analyzed for whole-body concentrations of Al, V, Cr, Ni, Cu, As, Pb, Cd, Zn, Ag, Sr, and Se. After the effects of dry mass were removed, tissue concentrations of six elements (Al, V, Cr, Ni, Cu, As, and Pb) decreased from the late larval stage through metamorphosis. Decreases in concentrations through metamorphosis ranged from 40% for Cu to 97% for Al. Tissue concentrations of these elements were also similar or higher in spring; Al and Cr concentrations were 34 and 90% higher in the spring, respectively, whereas As, Ni, Cu, and Pb concentrations were {lt} 10% higher. Concentrations of Cd, Se, and Ag varied among seasons but not among stages; Cd and Ag concentrations were 40 and 62% lower, respectively, and Se concentrations were 21% higher in spring. Concentrations of Zn varied only among stages; concentrations decreased gradually through late larval stage and then increased through metamorphosis. Concentrations of Sr varied among stages, but this variation was dependent on the season. Concentrations of Sr were higher in larval stages during the spring, but because concentrations of Sr increased 122% through metamorphosis in the fall and only 22% in the spring, concentrations were higher in fall metamorphs when compared with spring metamorphs. Our results indicate that metamorphosis and season of metamorphosis affects trace element concentrations in bullfrogs and may have important implications for the health of juveniles and the transfer of pollutants from the aquatic to the terrestrial environment.

  1. Silver nanoparticles induce developmental stage-specific embryonic phenotypes in zebrafish

    Science.gov (United States)

    Lee, Kerry J.; Browning, Lauren M.; Nallathamby, Prakash D.; Osgood, Christopher J.; Xu, Xiao-Hong Nancy

    2013-11-01

    Much is anticipated from the development and deployment of nanomaterials in biological organisms, but concerns remain regarding their biocompatibility and target specificity. Here we report our study of the transport, biocompatibility and toxicity of purified and stable silver nanoparticles (Ag NPs, 13.1 +/- 2.5 nm in diameter) upon the specific developmental stages of zebrafish embryos using single NP plasmonic spectroscopy. We find that single Ag NPs passively diffuse into five different developmental stages of embryos (cleavage, early-gastrula, early-segmentation, late-segmentation, and hatching stages), showing stage-independent diffusion modes and diffusion coefficients. Notably, the Ag NPs induce distinctive stage and dose-dependent phenotypes and nanotoxicity, upon their acute exposure to the Ag NPs (0-0.7 nM) for only 2 h. The late-segmentation embryos are most sensitive to the NPs with the lowest critical concentration (CNP,c nanotoxicity, upon their acute exposure to the Ag NPs (0-0.7 nM) for only 2 h. The late-segmentation embryos are most sensitive to the NPs with the lowest critical concentration (CNP,c << 0.02 nM) and highest percentages of cardiac abnormalities, followed by early-segmentation embryos (CNP,c < 0.02 nM), suggesting that disruption of cell differentiation by the NPs causes the most toxic effects on embryonic development. The cleavage-stage embryos treated with the NPs develop into a wide variety of phenotypes (abnormal finfold, tail/spinal cord flexure, cardiac malformation/edema, yolk sac edema, and acephaly). These organ structures are not yet developed in cleavage-stage embryos, suggesting that the earliest determinative events to create these structures are ongoing, and disrupted by NPs, which leads to the downstream effects. In contrast, the hatching embryos are most resistant to the Ag NPs, and majority of embryos (94%) develop normally, and none of them develop abnormally. Interestingly, early-gastrula embryos are less sensitive

  2. Transcription profile data of phorbol esters biosynthetic genes during developmental stages in Jatropha curcas.

    Science.gov (United States)

    Jadid, Nurul; Mardika, Rizal Kharisma; Purwani, Kristanti Indah; Permatasari, Erlyta Vivi; Prasetyowati, Indah; Irawan, Mohammad Isa

    2018-06-01

    Jatropha curcas is currently known as an alternative source for biodiesel production. Beside its high free fatty acid content, J. curcas also contains typical diterpenoid-toxic compounds of Euphorbiaceae plant namely phorbol esters. This article present the transcription profile data of genes involved in the biosynthesis of phorbol esters at different developmental stages of leaves, fruit, and seed in Jatropha curcas . Transcriptional profiles were analyzed using reverse transcription-polymerase chain reaction (RT-PCR). We used two genes including GGPPS (Geranylgeranyl diphospate synthase), which is responsible for the formation of common diterpenoid precursor (GGPP) and CS (Casbene Synthase), which functions in the synthesis of casbene. Meanwhile, J. curcas Actin ( ACT ) was used as internal standard. We demonstrated dynamic of GGPPS and CS expression among different stage of development of leaves, fruit and seed in Jatropha .

  3. Distribution of potato spindle tuber viroid in reproductive organs of petunia during its developmental stages.

    Science.gov (United States)

    Matsushita, Yosuke; Tsuda, Shinya

    2014-09-01

    Embryo infection is important for efficient seed transmission of viroids. To identify the major pattern of seed transmission of viroids, we used in situ hybridization to histochemically analyze the distribution of Potato spindle tuber viroid (PSTVd) in each developmental stage of petunia (flowering to mature seed stages). In floral organs, PSTVd was present in the reproductive tissues of infected female × infected male and infected female × healthy male but not of healthy female × infected male before embryogenesis. After pollination, PSTVd was detected in the developed embryo and endosperm in all three crosses. These findings indicate that PSTVd is indirectly delivered to the embryo through ovule or pollen during the development of reproductive tissues before embryogenesis but not directly through maternal tissues as cell-to-cell movement during embryogenesis.

  4. Validation of reference genes in Solenopsis invicta in different developmental stages, castes and tissues.

    Directory of Open Access Journals (Sweden)

    Daifeng Cheng

    Full Text Available To accurately assess gene expression levels, it is essential to normalize real-time quantitative PCR (RT-qPCR data with suitable internal reference genes. For the red imported fire ant, Solenopsis invicta, reliable reference genes to assess the transcript expression levels of the target genes have not been previously investigated. In this study, we examined the expression levels of five candidate reference genes (rpl18, ef1-beta, act, GAPDH, and tbp in different developmental stages, castes and tissues of S. invicta. To evaluate the suitability of these genes as endogenous controls, three software-based approaches (geNorm, BestKeeper and NormFinder and one web-based comprehensive tool (RefFinder were used to analyze and rank the tested genes. Furthermore, the optimal number of reference gene(s was determined by the pairwise variation value. Our data showed that two of the five candidate genes, rpl18 and ef1-beta, were the most suitable reference genes because they have the most stable expression among different developmental stages, castes and tissues in S. invicta. Although widely used as reference gene in other species, in S. invicta the act gene has high variation in expression and was consequently excluded as a reliable reference gene. The two validated reference genes, rpl18 and ef1-beta, can be widely used for quantification of target gene expression with RT-qPCR technology in S. invicta.

  5. Genetic identification of female Cannabis sativa plants at early developmental stage.

    Science.gov (United States)

    Techen, Natascha; Chandra, Suman; Lata, Hemant; Elsohly, Mahmoud A; Khan, Ikhlas A

    2010-11-01

    Sequence-characterized amplified region (SCAR) markers were used to identify female plants at an early developmental stage in four different varieties of Cannabis sativa. Using the cetyl trimethylammonium bromide (CTAB) method, DNA was isolated from two-week-old plants of three drug-type varieties (Terbag W1, Terbag K2, and Terbag MX) and one fiber-type variety (Terbag Fedora A7) of C. sativa grown under controlled environmental conditions through seeds. Attempts to use MADC2 (male-associated DNA from Cannabis sativa) primers as a marker to identify the sex of Cannabis sativa plants were successful. Amplification of genomic DNA using MADC2-F and MADC2-R primers produced two distinct fragments, one with a size of approximately 450 bp for female plants and one for male plants with a size of approximately 300 bp. After harvesting the tissues for DNA extraction, plants were subjected to a flowering photoperiod (i.e., 12-h light cycle), and the appearance of flowers was compared with the DNA analysis. The results of the molecular analysis were found to be concordant with the appearance of male or female flowers. The results of this study represent a quick and reliable technique for the identification of sex in Cannabis plants using SCAR markers at a very early developmental stage. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Developmental stage- and DNA damage-specific functions of C. elegans FANCD2

    International Nuclear Information System (INIS)

    Lee, Kyong Yun; Yang, Insil; Park, Jung-Eun; Baek, Ok-Ryun; Chung, Kee Yang; Koo, Hyeon-Sook

    2007-01-01

    In this study, we set out to investigate the role of Fanconi anemia complementation group D2 protein (FANCD2) in developmental stage-specific DNA damage responses in Caenorhabditis elegans. A mutant C. elegans strain containing a deletion in the gene encoding the FANCD2 homolog, FCD-2, exhibited egg-laying defects, precocious oogenesis, and partial defects in fertilization. The mutant strain also had a lower hatching rate than the wild-type after γ-irradiation of embryos, but not after the irradiation of pachytene stage germ cells. This mutation sensitized pachytene stage germ cells to the genotoxic effects of photoactivated psoralen, as seen by a greatly reduced hatching rate and increased chromosomal aberrations. This mutation also enhanced physiological M-phase arrest and apoptosis. Taken together, our data reveal that the C. elegans FANCD2 homolog participates in the repair of spontaneous DNA damage and DNA crosslinks, not only in proliferating cells but also in pachytene stage cells, and it may have an additional role in double-stranded DNA break repair during embryogenesis

  7. Proteomic analysis of young leaves at three developmental stages in an albino tea cultivar

    Directory of Open Access Journals (Sweden)

    Li Juan

    2011-08-01

    Full Text Available Abstract Background White leaf No.1 is a typical albino tea cultivar grown in China and it has received increased attention in recent years due to the fact that white leaves containing a high level of amino acids, which are very important components affecting the quality of tea drink. According to the color of its leaves, the development of this tea cultivar is divided into three stages: the pre-albinistic stage, the albinistic stage and the regreening stage. To understand the intricate mechanism of periodic albinism, a comparative proteomic approach based on two-dimensional electrophoresis (2-DE and mass spectrometry was adopted first time to identify proteins that changed in abundance during the three developmental periods. Results The 2-DE results showed that the expression level of 61 protein spots varied markedly during the three developmental stages. To analyze the functions of the significantly differentially expressed protein spots, 30 spots were excised from gels and analyzed by matrix-assisted laser desorption ionization-time of flight-tandem mass spectrometry. Of these, 26 spots were successfully identified. All identified protein spots were involved in metabolism of carbon, nitrogen and sulfur, photosynthesis, protein processing, stress defense and RNA processing, indicating these physiological processes may play crucial roles in the periodic albinism. Quantitative real-time RT-PCR analysis was used to assess the transcriptional level of differentially expressed proteins. In addition, the ultrastructural studies revealed that the etioplast-chloroplast transition in the leaf cell of White leaf No. 1 was inhibited and the grana in the chloroplast was destroyed at the albinistic stage. Conclusions In this work, the proteomic analysis revealed that some proteins may have important roles in the molecular events involved in periodic albinism of White leaf No. 1 and identificated many attractive candidates for further investigation. In

  8. Two-stage discrete-continuous multi-objective load optimization: An industrial consumer utility approach to demand response

    International Nuclear Information System (INIS)

    Abdulaal, Ahmed; Moghaddass, Ramin; Asfour, Shihab

    2017-01-01

    Highlights: •Two-stage model links discrete-optimization to real-time system dynamics operation. •The solutions obtained are non-dominated Pareto optimal solutions. •Computationally efficient GA solver through customized chromosome coding. •Modest to considerable savings are achieved depending on the consumer’s preference. -- Abstract: In the wake of today’s highly dynamic and competitive energy markets, optimal dispatching of energy sources requires effective demand responsiveness. Suppliers have adopted a dynamic pricing strategy in efforts to control the downstream demand. This method however requires consumer awareness, flexibility, and timely responsiveness. While residential activities are more flexible and schedulable, larger commercial consumers remain an obstacle due to the impacts on industrial performance. This paper combines methods from quadratic, stochastic, and evolutionary programming with multi-objective optimization and continuous simulation, to propose a two-stage discrete-continuous multi-objective load optimization (DiCoMoLoOp) autonomous approach for industrial consumer demand response (DR). Stage 1 defines discrete-event load shifting targets. Accordingly, controllable loads are continuously optimized in stage 2 while considering the consumer’s utility. Utility functions, which measure the loads’ time value to the consumer, are derived and weights are assigned through an analytical hierarchy process (AHP). The method is demonstrated for an industrial building model using real data. The proposed method integrates with building energy management system and solves in real-time with autonomous and instantaneous load shifting in the hour-ahead energy price (HAP) market. The simulation shows the occasional existence of multiple load management options on the Pareto frontier. Finally, the computed savings, based on the simulation analysis with real consumption, climate, and price data, ranged from modest to considerable amounts

  9. Variation in chemical components and biological activity of Pterocarya fraxinifolia Lam. stems at different developmental stages

    Directory of Open Access Journals (Sweden)

    M. Akhbari

    2017-07-01

    Full Text Available Background and objectives: Pterocarya fraxinifolia Lam. is a deciduous, fast-growing tree from walnut family. The stem barks and fruits of the plant have been used as diaphoretic in traditional medicine. Variation in the quantity and quality of the essential oil and extract of stems of the plant at different developmental stages was evaluated in addition to assessing the antimicrobial, cytotoxic and radical scavenging activities in the present study. Methods: Different developmental stages of the plant’s stem (i.e. vegetative, flowering, immature fruit and mature fruit were subjected to hydro-distillation for obtaining the essential oil. The methanol extract of the samples was obtained by Soxhlet apparatus. Chemical composition of the oils was analyzed by gas chromatography/mass spectroscopy (GC/MS. Antimicrobial activity of the oils and extracts were determined against three Gram-positive and five Gram-negative bacteria and two fungi by disc diffusion method. Antioxidant activity of the samples was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH and β-carotene assays. Total phenolics content of extracts was determined using Folin-Ciocalteau reagent and cytotoxic effect was determined by brine shrimp lethality bioassay. Results: Hexadecanoic acid was one of the major components in all essential oil samples. All samples showed good antimicrobial activity against tested strains. Antioxidant activity of the extracts was comparable to the synthetic standard (butylated hydroxytoluene. The highest total phenolic content and cytotoxic effect were detected for the mature fruit stage of the plant extract and essential oil, respectively. Conclusion: Showing considerable antioxidant and cytotoxic effects, suggested the plant as a good candidate for further investigations.

  10. Transcriptome profiles of embryos before and after cleavage in Eriocheir sinensis: identification of developmental genes at the earliest stages

    Science.gov (United States)

    Hui, Min; Cui, Zhaoxia; Liu, Yuan; Song, Chengwen

    2017-07-01

    In crab, embryogenesis is a complicated developmental program marked by a series of critical events. RNA-Sequencing technology offers developmental biologists a way to identify many more developmental genes than ever before. Here, we present a comprehensive analysis of the transcriptomes of Eriocheir sinensis oosperms (Os) and embryos at the 2-4 cell stage (Cs), which are separated by a cleavage event. A total of 18 923 unigenes were identified, and 403 genes matched with gene ontology (GO) terms related to developmental processes. In total, 432 differentially expressed genes (DEGs) were detected between the two stages. Nine DEGs were specifically expressed at only one stage. These DEGs may be relevant to stage-specific molecular events during development. A number of DEGs related to `hedgehog signaling pathway', `Wnt signaling pathway' `germplasm', `nervous system', `sensory perception' and `segment polarity' were identified as being up-regulated at the Cs stage. The results suggest that these embryonic developmental events begin before the early cleavage event in crabs, and that many of the genes expressed in the two transcriptomes might be maternal genes. Our study provides ample information for further research on the molecular mechanisms underlying crab development.

  11. Determination of male strobilus developmental stages by cytological and gene expression analyses in Japanese cedar (Cryptomeria japonica).

    Science.gov (United States)

    Tsubomura, Miyoko; Kurita, Manabu; Watanabe, Atsushi

    2016-05-01

    The molecular mechanisms that control male strobilus development in conifers are largely unknown because the developmental stages and related genes have not yet been characterized. The determination of male strobilus developmental stages will contribute to genetic research and reproductive biology in conifers. Our objectives in this study were to determine the developmental stages of male strobili by cytological and transcriptome analysis, and to determine the stages at which aberrant morphology is observed in a male-sterile mutant of Cryptomeria japonica D. Don to better understand the molecular mechanisms that control male strobilus and pollen development. Male strobilus development was observed for 8 months, from initiation to pollen dispersal. A set of 19,209 expressed sequence tags (ESTs) collected from a male reproductive library and a pollen library was used for microarray analysis. We divided male strobilus development into 10 stages by cytological and transcriptome analysis. Eight clusters (7324 ESTs) exhibited major changes in transcriptome profiles during male strobili and pollen development in C. japonica Two clusters showed a gradual increase and decline in transcript abundance, respectively, while the other six clusters exhibited stage-specific changes. The stages at which the male sterility trait of Sosyun was expressed were identified using information on male strobilus and pollen developmental stages and gene expression profiles. Aberrant morphology was observed cytologically at Stage 6 (microspore stage), and differences in expression patterns compared with wild type were observed at Stage 4 (tetrad stage). © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. An updated insight into the Sialotranscriptome of Triatoma infestans: developmental stage and geographic variations.

    Directory of Open Access Journals (Sweden)

    Alexandra Schwarz

    2014-12-01

    Full Text Available Triatoma infestans is the main vector of Chagas disease in South America. As in all hematophagous arthropods, its saliva contains a complex cocktail that assists blood feeding by preventing platelet aggregation and blood clotting and promoting vasodilation. These salivary components can be immunologically recognized by their vector's hosts and targeted with antibodies that might disrupt blood feeding. These antibodies can be used to detect vector exposure using immunoassays. Antibodies may also contribute to the fast evolution of the salivary cocktail.Salivary gland cDNA libraries from nymphal and adult T. infestans of breeding colonies originating from different locations (Argentina, Chile, Peru and Bolivia, and cDNA libraries originating from F1 populations of Bolivia, were sequenced using Illumina technology. Coding sequences (CDS were extracted from the assembled reads, the numbers of reads mapped to these CDS, sequences were functionally annotated and polymorphisms determined.Over five thousand CDS, mostly full length or near full length, were publicly deposited on GenBank. Transcripts that were over 10-fold overexpressed from different geographical regions, or from different developmental stages were identified. Polymorphisms were mapped to derived coding sequences, and found to vary between developmental instars and geographic origin of the biological material. This expanded sialome database from T. infestans should be of assistance in future proteomic work attempting to identify salivary proteins that might be used as epidemiological markers of vector exposure, or proteins of pharmacological interest.

  13. In vitro effects of Musa x paradisiaca extracts on four developmental stages of Haemonchus contortus.

    Science.gov (United States)

    Marie-Magdeleine, C; Udino, L; Philibert, L; Bocage, B; Archimede, H

    2014-02-01

    This study was carried out to evaluate the in vitro effect of Musa x paradisiaca stem and leaf against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and/or dichloromethane) of Musa x paradisiaca stem and leaf were tested in vitro on four developmental stages of H. contortus using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI) and adult worm motility assay (AWM). The highly significant (P67% for each extract) and the negative effect of the dichloromethane extract of leaf on adult worm motility (43% of inhibition of motility after 24h of incubation) compared to the negative controls, suggest anthelmintic properties of Musa x paradisiaca stem and leaf against H. contortus. The active principles responsible for the activity could be secondary metabolites such as terpenoid and flavonoid compounds present in the leaf and stem of the plant. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Peer, parent and media influences on adolescent smoking by developmental stage.

    Science.gov (United States)

    Villanti, Andrea; Boulay, Marc; Juon, Hee-Soon

    2011-01-01

    Previous studies of social influences on adolescent smoking have focused on peers and parents, using data collected prior the 1998 Master Settlement Agreement. This study used the 2004 wave of the National Youth Tobacco Survey to examine associations between peer smoking, smoking at home, tobacco-related media exposure, and smoking behavior during early and middle adolescence. Findings indicate that peer smoking and smoking at home remain strongly associated with current smoking among early and middle adolescents, controlling for gender, race/ethnicity and exposure to tobacco industry and anti-tobacco media. The magnitude of the association between peer smoking and current smoking decreases from early adolescence to middle adolescence while the association between smoking at home and current smoking is static across developmental stage. Exposure to tobacco-related media is associated with increased current and former smoking in both early and middle adolescence. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Survey on morphometric characteristic of different developmental stages of Dermacentor marginatus under laboratory conditions

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    Mohammad Mehdi Darvishi

    2014-09-01

    Full Text Available Objective: To study the morphometric characteristics and biology of different developmental stages of Dermacentor marginatus (D. marginatus under laboratory conditions. Methods: D. marginatus ticks were collected from sheep in Shahmirzad and suburb. The identification of D. marginatus was carried out by means of stereoscope and light microscope according to available systematic keys. Nourished female ticks weight and their length of body, capitulum and mouth parts were measured. After laying eggs and breeding, the weight of all developmental larva stages and the length of mouth parts were measured and recorded carefully. Results: The mean of egg dimension was 566 µm伊436 µm. The length of unfed larva body, hypostome and capitulum were (690依10 µm, (75依5 µm and (172依7 µm, respectively. The weight of egg was calculated 0.05 mg and the weight of unfed larva, nymph and female were 0.02 mg, 0.14 mg and 4.66 mg, respectively; whereas the weight of replete larva, nymph and female were recorded 0.5 mg, 11 mg and 380 mg, respectively. Moreover, the length of unfed nymph, hypostome and capitulum were recorded (1300依50 µm, (135依5 µm and (280依10 µm, respectively. The longest length and width in replete female were observed to be 12.6 mm伊8.4 mm. Conclusions: The current investigation presents new information on biology of D. marginatus under standard laboratory conditions. Besides, investigation on ticks under laboratory conditions increases our knowledge regarding their biology and potential risks.

  16. The developmental stages of a community-university partnership: the experience of Padres Informados/Jovenes Preparados.

    Science.gov (United States)

    Allen, Michele L; Svetaz, A Veronica; Hurtado, G Ali; Linares, Roxana; Garcia-Huidobro, Diego; Hurtado, Monica

    2013-01-01

    Strong and sustained community-university partnerships are necessary for community-based participatory translational research. Little attention has been paid to understanding the trajectory of research partnerships from a developmental perspective. To propose a framework describing partnership development and maturation based on Erikson's eight stages of psychosocial development and describe how our collaboration is moving through those stages. Collaborators engaged in three rounds of iterative reflection regarding characteristics and contributors to the maturation of the Padres Informados/Jovenes Preparados (Informed Parents/Prepared Youth [PI/JP]) partnership. Each stage is characterized by broad developmental partnership tasks. Conflict or tension within the partnership is often a part of achieving the associated tasks. The strengths developed at each stage prepare the partnership for challenges associated with subsequent stages. This framework could provide a means for partnerships to reflect on their strengths and challenges at a given time point, and to help understand why some partnerships fail whereas others achieve maturity.

  17. Retina damage after exposure to UVA radiation on the early developmental stages of the Egyptian toad Bufo regularis Reuss

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    Alaa El-Din H. Sayed

    2016-10-01

    Full Text Available The present study was carried out to investigate the histological and histochemical changes in the retina on different developmental stages of Egyptian toad Bufo regularis. Our experiment started when tadpoles begin to feed. The adapted embryos are divided into 3 large tanks of 200 embryos each, collections of samples started from feeding age every three days. Both histological and histochemical results showed that the general architecture of the retina organ is correlated with the state of development. Therefore, it displayed different characteristic features depending on the investigated developmental stage starting from the larval stage (feeding began, stage 44 and ending with the post-metamorphic stage 66. Also, the present work aimed to study the chronic effects of UVA on the retina structure of B. regularis during development and metamorphosis for the first time.

  18. Morphological and histomorphological structures of testes and ovaries in early developmental stages of the silkworm, Bombyx mori.

    Science.gov (United States)

    Sakai, Hiroki; Kirino, Yohei; Katsuma, Susumu; Aoki, Fugaku; Suzuki, Masataka G

    2016-01-01

    The gonad develops as a testis in male or an ovary in female. In the silkworm, B. mori , little is known about testis and ovary in the embryonic stages and early larval stages. In this study, we performed morphological and histomorphological observations of ovaries and testes from the late embryonic stage to the 1st instar larval stage. Results obtained with lack of accurate information on sex of examined individuals may be misleading, thus we performed phenotypic observations of gonads by utilizing sex-limited strain that enables us to easily discriminate female embryos from male ones based on those egg colors. In testis, four testicular follicles were clearly observed in the testis at the first instar larval stage, and boundary layers were formed between the testicular follicles. At the late embryonic stage, the testis consisted of four testicular follicles, while the boundary layers were still obscure. In ovary, four ovarioles were easily recognizable in the ovary at the first instar larval stage, and boundary layers were formed between the ovarioles. However, in the late embryonic stage, it was quite difficult to identify four ovarioles. Morphological characteristics were almost similar between testis and ovary in early developmental stages. Our present study demonstrates that the most reliable difference between testis and ovary in early developmental stages is the attaching point of the duct. Formation and development of the duct may be sensitive to the sex-determining signal and display sexual dimorphism in early embryonic stages.

  19. AFSC/RACE/SAP/Long: Data from: A novel quantitative model of multiple discrete stage transitions applied to crustacean larval development

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set describes the holding temperatures and developmental stages of larvae of red and blue king crab (Paralithodes camtschaticus and P. platypus) reared to...

  20. Host species and developmental stage, but not host social structure, affects bacterial community structure in socially polymorphic bees.

    Science.gov (United States)

    McFrederick, Quinn S; Wcislo, William T; Hout, Michael C; Mueller, Ulrich G

    2014-05-01

    Social transmission and host developmental stage are thought to profoundly affect the structure of bacterial communities associated with honey bees and bumble bees, but these ideas have not been explored in other bee species. The halictid bees Megalopta centralis and M. genalis exhibit intrapopulation social polymorphism, which we exploit to test whether bacterial communities differ by host social structure, developmental stage, or host species. We collected social and solitary Megalopta nests and sampled bees and nest contents from all stages of host development. To survey these bacterial communities, we used 16S rRNA gene 454 pyrosequencing. We found no effect of social structure, but found differences by host species and developmental stage. Wolbachia prevalence differed between the two host species. Bacterial communities associated with different developmental stages appeared to be driven by environmentally acquired bacteria. A Lactobacillus kunkeei clade bacterium that is consistently associated with other bee species was dominant in pollen provisions and larval samples, but less abundant in mature larvae and pupae. Foraging adults appeared to often reacquire L. kunkeei clade bacteria, likely while foraging at flowers. Environmental transmission appears to be more important than social transmission for Megalopta bees at the cusp between social and solitary behavior. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  1. Proteomic Analysis of Aphid-Resistant and -Sensitive Rose (Rosa Hybrida) Cultivars at Two Developmental Stages.

    Science.gov (United States)

    Muneer, Sowbiya; Jeong, Hai Kyoung; Park, Yoo Gyeong; Jeong, Byoung Ryong

    2018-05-25

    The rose is one the most commercially grown and costly ornamental plants because of its aesthetic beauty and aroma. A large number of pests attack its buds, flowers, leaves, and stem at every growing stage due to its high sugar content. The most common pest on roses are aphids which are considered to be the major cause for product loss. Aphid infestations lead to major changes in rose plants, such as large and irregular holes in petals, intact leaves and devouring tissues. It is hypothesized that different cut rose cultivars would have different levels of sensitivity or resistance to aphids, since different levels of infestation are observed in commercially cut rose production greenhouses. The present work compared four cut rose cultivars which were bred in Korea and were either resistant or sensitive to aphid infestation at different flower developmental stages. An integrative study was conducted using comprehensive proteome analyses. Proteins related to ubiquitin metabolism and the stress response were differentially expressed due to aphid infestation. The regulations and possible functions of identified proteins are presented in detail. The differential expressions of the identified proteins were validated by immunoblotting and blue native page. In addition, total sugar and carbohydrate content were also observed.

  2. Cuscuta europaea plastid apparatus in various developmental stages: localization of THF1 protein.

    Science.gov (United States)

    Švubová, Renáta; Ovečka, Miroslav; Pavlovič, Andrej; Slováková, L'udmila; Blehová, Alžbeta

    2013-05-01

    It was generally accepted that Cuscuta europaea is mostly adapted to a parasitic lifestyle with no detectable levels of chlorophylls. We found out relatively high level of chlorophylls (Chls a+b) in young developmental stages of dodder. Significant lowering of Chls (a+b) content and increase of carotenoid concentration was typical only for ontogenetically more developed stages. Lower content of photosynthesis-related proteins involved in Chls biosynthesis and in photosystem formation as well as low photochemical activity of PSII indicate that photosynthesis is not the main activity of C. europaea plastids. Previously, it has been shown in other species that the Thylakoid Formation Protein 1 (THF1) is involved in thylakoid membrane differentiation, plant-fungal and plant-bacterial interactions and in sugar signaling with its preferential localization to plastids. Our immunofluorescence localization studies and analyses of haustorial plasma membrane fractions revealed that in addition to plastids, the THF1 protein localizes also to the plasma membrane and plasmodesmata in developing C. europaea haustorium, most abundantly in the digitate cells of the endophyte primordium. These results are supported by western blot analysis, documenting the highest levels of the THF1 protein in "get together" tissues of dodder and tobacco. Based on the fact that photosynthesis is not a typical process in the C. europaea haustorium and on the extra-plastidial localization pattern of the THF1, our data support rather other functions of this protein in the complex relationship between C. europaea and its host.

  3. Chemical and functional properties of cell wall polymers from two cherry varieties at two developmental stages.

    Science.gov (United States)

    Basanta, María F; de Escalada Plá, Marina F; Stortz, Carlos A; Rojas, Ana M

    2013-01-30

    The cell wall polysaccharides of Regina and Sunburst cherry varieties at two developmental stages were extracted sequentially, and their changes in monosaccharide composition and functional properties were studied. The loosely-attached pectins presented a lower d-galacturonic acid/rhamnose ratio than ionically-bound pectins, as well as lower thickening effects of their respective 2% aqueous solution: the lowest Newtonian viscosity and shear rate dependence during the pseudoplastic phase. The main constituents of the cell wall matrix were covalently bound pectins (probably through diferulate cross-linkings), with long arabinan side chains at the RG-I cores. This pectin domain was also anchored into the XG-cellulose elastic network. Ripening occurred with a decrease in the proportion of HGs, water extractable GGM and xylogalacturonan, and with a concomitant increase in neutral sugars. Ripening was also associated with higher viscosities and thickening effects, and to larger distribution of molecular weights. The highest firmness and compactness of Regina cherry may be associated with its higher proportion of calcium-bound HGs localized in the middle lamellae of cell walls, as well as to some higher molar proportion of NS (Rha and Ara) in covalently bound pectins. These pectins showed significantly better hydration properties than hemicellulose and cellulose network. Chemical composition and functional properties of cell wall polymers were dependent on cherry variety and ripening stage, and helped explain the contrasting firmness of Regina and Sunburst varieties. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Modeling winter moth Operophtera brumata egg phenology: nonlinear effects of temperature and developmental stage on developmental rate

    NARCIS (Netherlands)

    Salis, Lucia; Lof, Marjolein; Van Asch, M.; Visser, Marcel E.

    2016-01-01

    Understanding the relationship between an insect's developmental rate and temperature is crucial to forecast insect phenology under climate change. In the winter moth Operophtera brumata timing of egg-hatching has severe fitness consequences on growth and reproduction as egg-hatching has to match

  5. Age estimation by dental developmental stages in children and adolescents in Iceland.

    Science.gov (United States)

    Vidisdottir, Sigridur Rosa; Richter, Svend

    2015-12-01

    Studies have shown that it is necessary to create a database for dental maturity for every population and compare it to others. The present study is the first one for dental development in the Icelandic population the age range being 4-24 years. It will help in forensic dental age estimation and will also help dentists, physicians, anthropologists, archaeologists and other professionals who rely on developmental age assessment in children and adolescents. In this present retrospective cross-sectional study, dental maturity was determined in 1100 Icelandic children and adolescents from orthopantomograms (OPGs). The first 100 were used for a pilot study and the remaining 1000 for the main study. A total of 23 subjects were excluded. The sample consisted of 508 girls and 469 boys from the age of 4-24 years and a dental developmental scoring system was used as a standard for determination of dental maturity stages. A total of 200 OPGs were studied both on the left and right side and the remaining on the right side. Dental maturity was established for all teeth and both genders, when the sample permitted, from the beginning of crown formation to the root apex closure. The Cronbach's Alpha reliability test showed high reliability, R=0.982. Girls in Iceland reach dental maturity root completed (stage 10, Rc) at 17.81 years of age for the maxillary and at 18.47 years for the mandibular teeth. Boys reach dental maturity root completed (stage 10, Rc) at 18.00 years of age in the maxilla and 17.63 in the mandible. There was no significant difference between left and right side (r=0.95-1.00) and there was no gender difference, except in root formation in maxillary and mandibular canines where girls reached root completed earlier than boys. A reliable database has been established in Iceland for tooth development in the age range of 4-24 years, which is compatible with international studies. These results will help forensic odontologists and other professionals to estimate with

  6. Developmental and physiological challenges of octopus (Octopus vulgaris) early life stages under ocean warming.

    Science.gov (United States)

    Repolho, Tiago; Baptista, Miguel; Pimentel, Marta S; Dionísio, Gisela; Trübenbach, Katja; Lopes, Vanessa M; Lopes, Ana Rita; Calado, Ricardo; Diniz, Mário; Rosa, Rui

    2014-01-01

    The ability to understand and predict the effects of ocean warming (under realistic scenarios) on marine biota is of paramount importance, especially at the most vulnerable early life stages. Here we investigated the impact of predicted environmental warming (+3 °C) on the development, metabolism, heat shock response and antioxidant defense mechanisms of the early stages of the common octopus, Octopus vulgaris. As expected, warming shortened embryonic developmental time by 13 days, from 38 days at 18 °C to 25 days at 21 °C. Concomitantly, survival decreased significantly (~29.9 %). Size at hatching varied inversely with temperature, and the percentage of smaller premature paralarvae increased drastically, from 0 % at 18 °C to 17.8 % at 21 °C. The metabolic costs of the transition from an encapsulated embryo to a free planktonic form increased significantly with warming, and HSP70 concentrations and glutathione S-transferase activity levels were significantly magnified from late embryonic to paralarval stages. Yet, despite the presence of effective antioxidant defense mechanisms, ocean warming led to an augmentation of malondialdehyde levels (an indicative of enhanced ROS action), a process considered to be one of the most frequent cellular injury mechanisms. Thus, the present study provides clues about how the magnitude and rate of ocean warming will challenge the buffering capacities of octopus embryos and hatchlings' physiology. The prediction and understanding of the biochemical and physiological responses to warmer temperatures (under realistic scenarios) is crucial for the management of highly commercial and ecologically important species, such as O. vulgaris.

  7. Flow paths of water and sediment in a tidal marsh: relations with marsh developmental stage and tidal inundation height

    NARCIS (Netherlands)

    Temmerman, S.; Bouma, T.J.; Govers, G.; Lauwaet, D.

    2005-01-01

    This study provides new insights in the relative role of tidal creeks and the marsh edge in supplying water and sediments to and from tidal marshes for a wide range of tidal inundation cycles with different high water levels and for marsh zones of different developmental stage. Net import or export

  8. Ascaroside expression in Caenorhabditis elegans is strongly dependent on diet and developmental stage.

    Directory of Open Access Journals (Sweden)

    Fatma Kaplan

    2011-03-01

    Full Text Available The ascarosides form a family of small molecules that have been isolated from cultures of the nematode Caenorhabditis elegans. They are often referred to as "dauer pheromones" because most of them induce formation of long-lived and highly stress resistant dauer larvae. More recent studies have shown that ascarosides serve additional functions as social signals and mating pheromones. Thus, ascarosides have multiple functions. Until now, it has been generally assumed that ascarosides are constitutively expressed during nematode development.Cultures of C. elegans were developmentally synchronized on controlled diets. Ascarosides released into the media, as well as stored internally, were quantified by LC/MS. We found that ascaroside biosynthesis and release were strongly dependent on developmental stage and diet. The male attracting pheromone was verified to be a blend of at least four ascarosides, and peak production of the two most potent mating pheromone components, ascr#3 and asc#8 immediately preceded or coincided with the temporal window for mating. The concentration of ascr#2 increased under starvation conditions and peaked during dauer formation, strongly supporting ascr#2 as the main population density signal (dauer pheromone. After dauer formation, ascaroside production largely ceased and dauer larvae did not release any ascarosides. These findings show that both total ascaroside production and the relative proportions of individual ascarosides strongly correlate with these compounds' stage-specific biological functions.Ascaroside expression changes with development and environmental conditions. This is consistent with multiple functions of these signaling molecules. Knowledge of such differential regulation will make it possible to associate ascaroside production to gene expression profiles (transcript, protein or enzyme activity and help to determine genetic pathways that control ascaroside biosynthesis. In conjunction with findings

  9. The Effect of Cirata Reservoir Sediment on Early Developmental Stage of Common Carp (Cyprinus carpio Embryo

    Directory of Open Access Journals (Sweden)

    Yuni Pujihastuti

    2009-07-01

    Full Text Available Sedimentation at Cirata reservoir may directly and indirectly influence fish particularly fish which have an adhesive characteristic at its early developmental stage such as common carp (Cyprinus carpio. Sample of sediment was collected from Cirata reservoir using Eikmand dredge at a depth of 80 m. The sample was subsequently centrifuged at 5500 rpm for 10 min. The supernatant obtained was then used for toxicity test on common carp at early developmental stage. In this test, four treatments were applied based on the concentration of sediment supernatant, namely: 0, 8.33, 16.60 and 24.90 %. The results showed that a higher sediment supernatant concentration resulted in lower egg yolk absorption rate, lower relative growth rate in length, lower egg yolk efficiency and higher egg and larval abnormality.  Higher sediment supernatant concentration also resulted in lower hatching percentage of common carp larva. The damage of eggs and larval morphologies in treatments with sediment supernatant was likely caused by the presence Pb and organic matters which act in synergy. Keywords :  sediment, Cirata, embryo, common carp   ABSTRAK Sedimentasi di Waduk Cirata secara langsung dan tidak langsung akan berpengaruh terhadap kehidupan ikan khususnya tahap awal perkembangan ikan yang bersifat adhesiveseperti ikan mas (Cyprinus carpio.  Sampel sedimen waduk Cirata diambil dengan Eikmand dredge pada kedalaman 80 m.  Hasil ekstrak di sentrifugasi dengan kecepatan 5500 rpm selama 10 menit untuk diambil air pori sedimennya.  Air pori digunakan sebagai bahan uji toksisitas terhadap perkembangan awal ikan mas dengan perlakuan 0; 8,33; 16,60 dan 24,90 %. Hasil uji toksisitas diperoleh bahwa semakin tinggi konsentrasi air pori dari sediment maka semakin rendah laju penyerapan kuning telur Laju pertumbuhan relatif panjang embrio pada berbagai konsentrasi juga diperoleh bahwa semakin tinggi konsentrasi air sedimen maka semakin rendah laju pertumbuhan relatif

  10. Transcriptome analysis of reproductive tissue and intrauterine developmental stages of the tsetse fly (Glossina morsitans morsitans

    Directory of Open Access Journals (Sweden)

    Wu Yineng

    2010-03-01

    Full Text Available Abstract Background Tsetse flies, vectors of African trypanosomes, undergo viviparous reproduction (the deposition of live offspring. This reproductive strategy results in a large maternal investment and the deposition of a small number of progeny during a female's lifespan. The reproductive biology of tsetse has been studied on a physiological level; however the molecular analysis of tsetse reproduction requires deeper investigation. To build a foundation from which to base molecular studies of tsetse reproduction, a cDNA library was generated from female tsetse (Glossina morsitans morsitans reproductive tissues and the intrauterine developmental stages. 3438 expressed sequence tags were sequenced and analyzed. Results Analysis of a nonredundant catalogue of 1391 contigs resulted in 520 predicted proteins. 475 of these proteins were full length. We predict that 412 of these represent cytoplasmic proteins while 57 are secreted. Comparison of these proteins with other tissue specific tsetse cDNA libraries (salivary gland, fat body/milk gland, and midgut identified 51 that are unique to the reproductive/immature cDNA library. 11 unique proteins were homologus to uncharacterized putative proteins within the NR database suggesting the identification of novel genes associated with reproductive functions in other insects (hypothetical conserved. The analysis also yielded seven putative proteins without significant homology to sequences present in the public database (unknown genes. These proteins may represent unique functions associated with tsetse's viviparous reproductive cycle. RT-PCR analysis of hypothetical conserved and unknown contigs was performed to determine basic tissue and stage specificity of the expression of these genes. Conclusion This paper identifies 51 putative proteins specific to a tsetse reproductive/immature EST library. 11 of these proteins correspond to hypothetical conserved genes and 7 proteins are tsetse specific.

  11. Assembly of 5.5-Meter Diameter Developmental Barrel Segments for the Ares I Upper Stage

    Science.gov (United States)

    Carter, Robert W.

    2011-01-01

    Full scale assembly welding of Ares I Upper Stage 5.5-Meter diameter cryogenic tank barrel segments has been performed at the Marshall Space Flight Center (MSFC). One full-scale developmental article produced under the Ares 1 Upper Stage project is the Manufacturing Demonstration Article (MDA) Barrel. This presentation will focus on the welded assembly of this barrel section, and associated lessons learned. Among the MDA articles planned on the Ares 1 Program, the Barrel was the first to be completed, primarily because the process of manufacture from piece parts (barrel panels) utilized the most mature friction stir process planned for use on the Ares US program: Conventional fixed pin Friction Stir Welding (FSW). This process is in use on other space launch systems, including the Shuttle s External Tank, the Delta IV common booster core, the Delta II, and the Atlas V rockets. The goals for the MDA Barrel development were several fold: 1) to prove out Marshall Space Flight Center s new Vertical Weld Tool for use in manufacture of cylindrical barrel sections, 2) to serve as a first run for weld qualification to a new weld specification, and 3) to provide a full size cylindrical section for downstream use in precision cleaning and Spray-on Foam Insulation development. The progression leading into the welding of the full size barrel included sub scale panel welding, subscale cylinder welding, a full length confidence weld, and finally, the 3 seamed MDA barrel processing. Lessons learned on this MDA program have been carried forward into the production tooling for the Ares 1 US Program, and in the use of the MSFC VWT in processing other large scale hardware, including two 8.4 meter diameter Shuttle External Tank barrel sections that are currently being used in structural analysis to validate shell buckling models.

  12. Transcriptome Analysis of Two Different Developmental Stages of Paeonia lactiflora Seeds

    Directory of Open Access Journals (Sweden)

    Yonglei Ma

    2017-01-01

    Full Text Available Paeonia lactiflora is a herbaceous flower in the family Paeoniaceae with both hypocotyl and epicotyl dormant seeds. We used high-throughput transcriptome sequencing on two different developmental stages of P. lactiflora seeds to identify seed dormancy and germination-related genes. We performed de novo assembly and annotated a total of 123,577 unigenes, which encoded 24,688 putative proteins with 47 GO categories. A total of 10,714 unigenes were annotated in the KEGG database, and 258 pathways were involved in the annotations. A total of 1795 genes were differentially expressed in the functional enrichment analysis. The key genes for seed germination and dormancy, such as GAI1 and ARF, were confirmed by quantitative reverse transcription-polymerase chain reaction analysis. This is the first report of sequencing the P. lactiflora seed transcriptome. Our results provide fundamental frame work and technical support for further selective breeding and cultivation of Paeonia. Our transcriptomic data also serves as the basis for future genetics and genomics research on Paeonia and its closely related species.

  13. Effect of developmental stage of HSC and recipient on transplant outcomes

    Science.gov (United States)

    Arora, Natasha; Wenzel, Pamela L.; McKinney-Freeman, Shannon L.; Ross, Samantha J.; Kim, Peter G.; Chou, Stephanie S.; Yoshimoto, Momoko; Yoder, Mervin C.; Daley, George Q.

    2014-01-01

    Summary The first hematopoietic stem cells (HSCs) that engraft irradiated adult mice arise in the aortagonad-mesonephros (AGM) on embryonic day 11.5 (E11.5). However, at this stage there is a discrepancy between the apparent frequency of HSCs suggested by imaging and their rarity when measured by limiting dilution transplant. We have attempted to reconcile this difference using neonatal recipients, which are more permissive for embryonic HSC engraftment. We found that embryonic HSCs from E9.5 and E10.5 preferentially engrafted neonates, whereas developmentally mature, definitive HSCs from E14.5 fetal liver (FL) or adult bone marrow (BM) more robustly engrafted adults. Neonatal engraftment was enhanced after treating adult BM-derived HSCs with interferon. Adult BM-derived HSCs preferentially homed to the liver in neonatal mice yet showed balanced homing to the liver and spleen in adults. These findings emphasize the functional differences between nascent and mature definitive HSCs. PMID:24914562

  14. Developmental toxicity of PAH mixtures in fish early life stages. Part II: adverse effects in Japanese medaka.

    Science.gov (United States)

    Le Bihanic, Florane; Clérandeau, Christelle; Le Menach, Karyn; Morin, Bénédicte; Budzinski, Hélène; Cousin, Xavier; Cachot, Jérôme

    2014-12-01

    In aquatic environments, polycyclic aromatic hydrocarbons (PAHs) mostly occur as complex mixtures, for which risk assessment remains problematic. To better understand the effects of PAH mixture toxicity on fish early life stages, this study compared the developmental toxicity of three PAH complex mixtures. These mixtures were extracted from a PAH-contaminated sediment (Seine estuary, France) and two oils (Arabian Light and Erika). For each fraction, artificial sediment was spiked at three different environmental concentrations roughly equivalent to 0.5, 4, and 10 μg total PAH g(-1) dw. Japanese medaka embryos were incubated on these PAH-spiked sediments throughout their development, right up until hatching. Several endpoints were recorded at different developmental stages, including acute endpoints, morphological abnormalities, larvae locomotion, and genotoxicity (comet and micronucleus assays). The three PAH fractions delayed hatching, induced developmental abnormalities, disrupted larvae swimming activity, and damaged DNA at environmental concentrations. Differences in toxicity levels, likely related to differences in PAH proportions, were highlighted between fractions. The Arabian Light and Erika petrogenic fractions, containing a high proportion of alkylated PAHs and low molecular weight PAHs, were more toxic to Japanese medaka early life stages than the pyrolytic fraction. This was not supported by the toxic equivalency approach, which appeared unsuitable for assessing the toxicity of the three PAH fractions to fish early life stages. This study highlights the potential risks posed by environmental mixtures of alkylated and low molecular weight PAHs to early stages of fish development.

  15. Identification of cytochrome P450 differentiated expression related to developmental stages in bromadiolone resistance in rats (Rattus norvegicus)

    DEFF Research Database (Denmark)

    Markussen, Mette; Heiberg, Ann-Charlotte; Fredholm, Merete

    2008-01-01

    over-express the Cyp2a1 gene. TGhe altered gene expression has been suggested to be involved in the bromadiolone resistance by facilitating enhanced anticoagulant metabolism. To investigate the gene expression of these cytochrome P450 genes in rats of different developmental stages we compared...... expression profiles, from 8-, 12- and 20-week-old resistant rats of the Danish strain to profiles of anticoagulant-susceptible rats of same ages. The three age-groups were selected to represent a group of pre-pubertal, pubertal and adult rats. We found expression profiles of the pre-pubertal and pubertal...... resistant rats to concur with profiles of the adults suggesting that cytochrome P450 enzymes are involved in the Danish bromadiolone resistance regardless of developmental stage. We also investigated the relative importance of the six cytochrome P450s in the different development stages of the resistant...

  16. The effect of seasonal harvesting on a single-species discrete population model with stage structure and birth pulses

    International Nuclear Information System (INIS)

    Gao Shujing; Chen Lansun

    2005-01-01

    In this paper, we propose an exploited single-species discrete model with stage structure for the dynamics in a fish population for which births occur in a single pulse once per time period. Using the stroboscopic map, we obtain an exact cycle of the system, and obtain the threshold conditions for its stability. Bifurcation diagrams are constructed with the birth rate as the bifurcation parameter, and these are observed to display complex dynamic behaviors, including chaotic bands with period windows, pitch-fork and tangent bifurcation. This suggests that birth pulse provides a natural period or cyclicity that makes the dynamical behavior more complex. Moreover, we show that the timing of harvesting has a strong impact on the persistence of the fish population, on the volume of mature fish stock and on the maximum annual-sustainable yield. An interesting result is obtained that, after the birth pulse, the earlier culling the mature fish, the larger harvest can tolerate

  17. Comparative anatomy and histology of developmental and parasitic stages in the life cycle of the lined sea anemone Edwardsiella lineata.

    Science.gov (United States)

    Reitzel, Adam M; Daly, Marymegan; Sullivan, James C; Finnerty, John R

    2009-02-01

    The evolution of parasitism is often accompanied by profound changes to the developmental program. However, relatively few studies have directly examined the developmental evolution of parasitic species from free-living ancestors. The lined sea anemone Edwardsiella lineata is a relatively recently evolved parasite for which closely related free-living outgroups are known, including the starlet sea anemone Nematostella vectensis. The larva of E. lineata parasitizes the ctenophore Mnemiopsis leidyi, and, once embedded in its host, the anemone assumes a novel vermiform body plan. That we might begin to understand how the developmental program of this species has been transformed during the evolution of parasitism, we characterized the gross anatomy, histology, and cnidom of the parasitic stage, post-parasitic larval stage, and adult stage of the E. lineata life cycle. The distinct parasitic stage of the life cycle differs from the post-parasitic larva with respect to overall shape, external ciliation, cnida frequency, and tissue architecture. The parasitic stage and planula both contain holotrichs, a type of cnida not previously reported in Edwardsiidae. The internal morphology of the post-parasitic planula is extremely similar to the adult morphology, with a complete set of mesenterial tissue and musculature despite this stage having little external differentiation. Finally, we observed 2 previously undocumented aspects of asexual reproduction in E. lineata: (1) the parasitic stage undergoes transverse fission via physal pinching, the first report of asexual reproduction in a pre-adult stage in the Edwardsiidae; and (2) the juvenile polyp undergoes transverse fission via polarity reversal, the first time this form of fission has been reported in E. lineata.

  18. Developmental Stage-Specific Manifestations of Absent TPO/c-MPL Signalling in Newborn Mice.

    Science.gov (United States)

    Lorenz, Viola; Ramsey, Haley; Liu, Zhi-Jian; Italiano, Joseph; Hoffmeister, Karin; Bihorel, Sihem; Mager, Donald; Hu, Zhongbo; Slayton, William B; Kile, Benjamin T; Sola-Visner, Martha; Ferrer-Marin, Francisca

    2017-12-01

    Congenital amegakaryocytic thrombocytopaenia (CAMT) is a disorder caused by c-MPL mutations that impair thrombopoietin (TPO) signalling, resulting in a near absence of megakaryocytes (MKs). While this phenotype is consistent in adults, neonates with CAMT can present with severe thrombocytopaenia despite normal MK numbers. To investigate this, we characterized MKs and platelets in newborn c-MPL –/– mice. Liver MKs in c-MPL –/– neonates were reduced in number and size compared with wild-type (WT) age-matched MKs, and exhibited ultrastructural abnormalities not found in adult c-MPL –/– MKs. Platelet counts were lower in c-MPL –/– compared with WT mice at birth and did not increase over the first 2 weeks of life. In vivo biotinylation revealed a significant reduction in the platelet half-life of c-MPL –/– newborn mice (P2) compared with age-matched WT pups, which was not associated with ultrastructural abnormalities. Genetic deletion of the pro-apoptotic Bak did not rescue the severely reduced platelet half-life of c-MPL –/– newborn mice, suggesting that it was due to factors other than platelets entering apoptosis early. Indeed, adult GFP+ (green fluorescent protein transgenic) platelets transfused into thrombocytopenic c-MPL –/– P2 pups also had a shortened lifespan, indicating the importance of cell-extrinsic factors. In addition, neonatal platelets from WT and c-MPL –/– mice exhibited reduced P-selectin surface expression following stimulation compared with adult platelets of either genotype, and platelets from c-MPL –/– neonates exhibited reduced glycoprotein IIb/IIIa (GPIIb/IIIa) activation in response to thrombin compared with age-matched WT platelets. Taken together, our findings indicate that c-MPL deficiency is associated with abnormal maturation of neonatal MKs and developmental stage-specific defects in platelet function.

  19. Efficacy of entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae) on developmental stages of house fly, Musca domestica.

    Science.gov (United States)

    Archana, M; D'Souza, Placid E; Patil, Jagadeesh

    2017-09-01

    The housefly, Musca domestica is a major domestic, medical and veterinary pest. The management of these flies reliance on insecticide, causes environmental constraints, insecticide resistance and residues in the meat, skin. Therefore one of the eco-friendly alternate methods is by using biological agents such as entomopathogenic nematodes (EPN). In the present study evaluated the survival of EPN species Steinernema feltiae , Heterorhabditis indica , S. carpocapsae , S. glaseri and S. abbasi in poultry manure and also their efficacy against different developmental stages of house fly. After exposing to poultry manure, S. feltiae showed more survival as followed by H. indica , S. carpocapsae , S. glaseri and S. abbasi in all exposition period. When the exposition period extended to 96 h, all nematode species survivability was drastically reduced. After exposing these nematodes to poultry manure at 24 h their virulence capacity against wax moth, Galleria mellonella showed all the nematode species were able cause 100% mortality. However their progeny production was significantly reduced. Fly eggs and pupae were refractory to these nematode infection. Petri dish without artificial diet assay showed that, second and 3rd-instar larvae were highly susceptible to EPNs as compared to larvae provided with artificial diet. H. indica showed high virulence capacity compared to other nematodes tested. Poultry manure assay revealed that, H. indica and S. carpocapsae caused minimal mortality where as S. feltiae , S. glaseri and S. abbasi did not cause any mortality. This may be because of poor survival and limited movement of nematodes in poultry manure which may be due to ammonia, other toxic substances in poultry manure. The decrease in larval mortality in manure suggests that biocontrol of housefly by using EPNs is unlikely.

  20. Comparative Transcriptomic Analysis of Grape Berry in Response to Root Restriction during Developmental Stages

    Directory of Open Access Journals (Sweden)

    Feng Leng

    2016-10-01

    Full Text Available Root restriction improved berry quality by being involved in diverse aspects of grapevine life. However, the molecular mechanism driving this process is not understood very well. In this study, the ‘Summer Black’ grape berry (Vitis vinifera × V. labrusca under root restriction was investigated, which showed an increase of total soluble solids (TSS, color index of red grapes (CIRG value, anthocyanins accumulation, total phenolics and total procyanidins contents during berry development compared with those in control berries. The transcriptomic changes induced by root restriction in ‘Summer Black’ grape over the course of berry development were analyzed by RNA-Seq method. A total of 29,971 genes were generated in ‘Summer Black’ grape berry during development, among which, 1606 genes were significantly responded to root restriction. Furthermore, 1264, 313, 141, 246 and 19 sequences were significantly changed at S1, S2, S3, S4 and S5 sample points, respectively. The gene (VIT_04s0023g02290 predicted as a salicylate O-methyltransferase was differentially expressed in all developmental stages. Gene Ontology (GO enrichment showed that response to organic nitrogen, response to endogenous stimulus, flavonoid metabolic process, phenylpropanoid biosynthetic process and cell wall macromolecule metabolic process were the main significant differential categories. Kyoto Encyclopedia of Genes and Genomes (KEGG pathway enrichment revealed plant–pathogen interaction, plant hormone signal transduction, flavone and flavonol biosynthesis, flavonoid biosynthesis and glucosinolate biosynthesis were the main significant differential pathways. The results of the present study provided a genetic base for the understanding of grape berry fruit quality improvement under root restriction.

  1. Age matters: Developmental stage of Danio rerio larvae influences photomotor response thresholds to diazinion or diphenhydramine

    Science.gov (United States)

    Kristofco, Lauren A.; Cruz, Luis Colon; Haddad, Samuel P.; Behra, Martine L; Chambliss, C. Kevin; Brooks, Bryan W.

    2016-01-01

    Because basic toxicological data is unavailable for the majority of industrial compounds, High Throughput Screening (HTS) assays using the embryonic and larval zebrafish provide promising approaches to define bioactivity profiles and identify potential adverse outcome pathways for previously understudied chemicals. Unfortunately, standardized approaches, including HTS experimental designs, for examining fish behavioral responses to contaminants are rarely available. In the present study, we examined movement behavior of larval zebrafish over 7 days (4–10 days post fertilization or dpf) during typical daylight workday hours to determine whether intrinsic activity differed with age and time of day. We then employed an early life stage approach using the Fish Embryo Test (FET) at multiple developmental ages to evaluate whether photomotor response (PMR) behavior differed with zebrafish age following exposure to diazinon (DZN), a well-studied orthophosphate insecticide, and diphenhydramine (DPH), an antihistamine that also targets serotonin reuptake transporters and the acetylcholine receptor. 72 h studies were conducted at 1–4, 4–7 and 7–10 dpf, followed by behavioral observations using a ViewPoint system at 4, 7 and 10 dpf. Distance traveled and swimming speeds were quantified; nominal treatment levels were analytically verified by isotope-dilution LC-MSMS. Larval zebrafish locomotion displayed significantly different (p environmentally realistic lowest observed effect concentration of 200 ng/L. Though ELS and FET studies with zebrafish typically focus on mortality or teratogenicity in 0–4 dpf organisms, behavioral responses of slightly older fish were several orders of magnitude more sensitive to DPH. Our observations highlight the importance of understanding the influence of time of day on intrinsic locomotor activity, and the age-specific hazards of aquatic contaminants to fish behavior. PMID:26431593

  2. Effects of buprofezin and diflubenzuron on various developmental stages of Asian citrus psyllid, Diaphorina citri.

    Science.gov (United States)

    Tiwari, Siddharth; Clayson, Paul J; Kuhns, Emily H; Stelinski, Lukasz L

    2012-10-01

    Diaphorina citri populations in Florida are developing resistance to commonly used neurotoxic insecticides. Alternatives to neurotoxins, such as insect growth regulators, are needed to control this season-long subtropical pest to prevent or delay development of insecticide resistance. In the present investigation, two insect growth regulators (IGRs), buprofezin and diflubenzuron, were evaluated against various developmental stages of D. citri. The 0-1-day-old D. citri eggs were more susceptible to buprofezin and diflubenzuron than the 3-4-day-old eggs. Adult emergence was completely suppressed by treating first- or third-instar nymphs with buprofezin or diflubenzuron at 30-240 or 23-184 µg mL(-1) rates respectively. Treatment of fifth-instar nymphs with diflubenzuron at a rate of 184 µg mL(-1) and with buprofezin at 30-240 µg mL(-1) rates resulted in approximately 20 and 15-80% reductions in adult emergence respectively. The mean number of eggs per plant was reduced at 5 days after topical treatment with diflubenzuron. Mean egg hatch per plant was reduced at 5 and 6-15 days after topical treatments with buprofezin and diflubenzuron respectively. Buprofezin and diflubenzuron effectively suppressed D. citri adult emergence. D. citri were more susceptible as early (first-third-instar) than late (fifth-instar) nymphs. Both IGRs inhibited egg production and egg hatch. Reduction in the number of subsequent offspring suggests reduced vertical transmission of Candidatus Liberibacter asiaticus, the pathogen thought to cause citrus greening disease. The present results indicate that both IGRs tested here should be effective tools for rotation in insecticide-based D. citri management programs. Copyright © 2012 Society of Chemical Industry.

  3. A Comparison of Staff Training Methods for Effective Implementation of Discrete Trial Teaching for Learners with Developmental Disabilities

    Science.gov (United States)

    Geiger, Kaneen Barbara

    2012-01-01

    Discrete trial teaching is an effective procedure for teaching a variety of skills to children with autism. However, it must be implemented with high integrity to produce optimal learning. Behavioral Skills Training (BST) is a staff training procedure that has been demonstrated to be effective. However, BST is time and labor intensive, and with…

  4. Television and Content Censorship: The Impact of Violent Content on the Developmental Stages in the Personality of the Nigerian Child

    OpenAIRE

    Oyama, Okim-Alobi; Ogbu, Silk

    2017-01-01

    Erik Erikson’s theorization of the psychosocial developmental stages of humans, reveal the fragility of children with special attention to their biological and psychosocial characterization. The adolescent age is the period where the child is adventurous, curious and eager to explore, as he becomes fascinated with the media and begins to try out behaviours and lifestyles of his opinion leaders. The Nigerian child is more or less enthralled about foreign movies, shows and musical videos charac...

  5. Non-uniform distribution pattern for differentially expressed genes of transgenic rice Huahui 1 at different developmental stages and environments.

    Directory of Open Access Journals (Sweden)

    Zhi Liu

    Full Text Available DNA microarray analysis is an effective method to detect unintended effects by detecting differentially expressed genes (DEG in safety assessment of genetically modified (GM crops. With the aim to reveal the distribution of DEG of GM crops under different conditions, we performed DNA microarray analysis using transgenic rice Huahui 1 (HH1 and its non-transgenic parent Minghui 63 (MH63 at different developmental stages and environmental conditions. Considerable DEG were selected in each group of HH1 under different conditions. For each group of HH1, the number of DEG was different; however, considerable common DEG were shared between different groups of HH1. These findings suggested that both DEG and common DEG were adequate for investigation of unintended effects. Furthermore, a number of significantly changed pathways were found in all groups of HH1, indicating genetic modification caused everlasting changes to plants. To our knowledge, our study for the first time provided the non-uniformly distributed pattern for DEG of GM crops at different developmental stages and environments. Our result also suggested that DEG selected in GM plants at specific developmental stage and environment could act as useful clues for further evaluation of unintended effects of GM plants.

  6. Morphological characteristics of developmental stages of Acanthamoeba and Naegleria species before and after staining by various techniques.

    Science.gov (United States)

    Ithoi, Init; Ahmad, Arine-Fadzlun; Mak, J W; Nissapatorn, Veeranoot; Lau, Yee-Ling; Mahmud, Rohela

    2011-11-01

    Seven stains were studied to determine the best color and contrast for staining the developmental stages of free living pathogenic Acanthamoeba and Naegleria species. The acid-fast bacilli stain (AFB) produced a blue color without contrast; trichrome-eosin and modified Field's showed various color contrasts; Giemsa, iron-hematoxylin, modified AFB and Gram produced only one color which distinguished the nucleus, nucleolus, cytoplasm, food- and water-vacuoles. The motile organs (acanthopodia, pseudopodia, lobopodia and flagella) were also clearly differentiated but produced a similar color as the cytoplasm. These motile organelles were first induced by incubating at 37 degrees C for at least 15 minutes and then fixing with methanol in order to preserve the protruding morphology prior to staining. The trichrome-eosin and iron-hematoxylin stains showed good color contrast for detecting all three stages, the trophozoite, cyst and flagellate; Giemsa and Gram stained the trophozoite and flagellate stages; the modified Field's and modified AFB stains stained only the trophozoite stage. Depending on the purpose, all these stains (except the AFB stain) can be used to identify the developmental stages of Acanthamoeba and Naegleria for clinical, epidemiological or public health use.

  7. Chemical composition and antifungal activity of Trigonella foenum-graecum L. varied with plant ploidy level and developmental stage

    Directory of Open Access Journals (Sweden)

    Faten Omezzine

    2017-05-01

    Full Text Available The efficacy of aerial parts’ organic extracts of diploid and mixoploid Trigonella foenum-graecum L. plants, harvested at three developmental stages (vegetative, flowering and fruiting was evaluated for their antifungal activity against Fusarium oxysporum f. sp. radicis-lycopersici (FORL and F. oxysporum f. sp. lycopersici (FOL. All tested extracts inhibited FORL and FOL mycelial growth. The organic extracts of diploid plants were found to be less toxic than mixoploid ones and this toxicity varied with the plant developmental stages. The diploids were most toxic, for the two strains, at the fruiting stage; however, mixoploids were more toxic at the vegetative stage for FOL and at flowering one for FORL. FOL was found to be more sensitive to fenugreek extracts when compared to FORL. LC–MS/MS analysis of methanolic extract of fenugreek aerial parts showed eleven different flavonol glycosides (quercetin, kaempferol and vitexin. Five novel components were identified, for the first time in fenugreek aerial parts, as kaempferol 3-O-β-d-glucopyranoside, kaempferol 7-O-glucoside, kaempferol 3-O-α-l-rhamnosyl (1→2 β-d-xyloside, kaempferol 7-O-β-d-glucopyranosyl (1–4 β-d-glucopyranoside and kaempferol 3-O-β-glucosyl (1→2 (6′-O-acetyl-β-d-galactoside, along with other known compounds of this species. To operate with the maximum efficiency, the allelopathic potential of a given plant, our study showed that it would be advisable to identify the most productive developmental stage of allelochemicals. Similarly, it seems that mixoploidy would be a simple and effective biotechnology tool to improve (in quantity and quality the allelochemicals’ production, since the extracts’ toxicity of diploid and mixoploid plants, was different.

  8. Age matters: Developmental stage of Danio rerio larvae influences photomotor response thresholds to diazinion or diphenhydramine

    International Nuclear Information System (INIS)

    Kristofco, Lauren A.; Cruz, Luis Colon; Haddad, Samuel P.; Behra, Martine L.; Chambliss, C. Kevin; Brooks, Bryan W.

    2016-01-01

    Highlights: • Fish behavior impairments by biological active contaminants are limited yet necessary. • Aquatic toxicology assays with 0–4 dpf larval zebrafish are increasingly important. • Larval zebrafish locomotion varied with age and daylight during typical workday hours. • Photomotor behavior to diazinion and diphenhydramine differed by larval zebrafish age. • Behavioral responses of 7–10 dpf zebrafish were markedly more sensitive than 0–4 dpf. - Abstract: Because basic toxicological data is unavailable for the majority of industrial compounds, High Throughput Screening (HTS) assays using the embryonic and larval zebrafish provide promising approaches to define bioactivity profiles and identify potential adverse outcome pathways for previously understudied chemicals. Unfortunately, standardized approaches, including HTS experimental designs, for examining fish behavioral responses to contaminants are rarely available. In the present study, we examined movement behavior of larval zebrafish over 7 days (4–10 days post fertilization or dpf) during typical daylight workday hours to determine whether intrinsic activity differed with age and time of day. We then employed an early life stage approach using the Fish Embryo Test (FET) at multiple developmental ages to evaluate whether photomotor response (PMR) behavior differed with zebrafish age following exposure to diazinon (DZN), a well-studied orthophosphate insecticide, and diphenhydramine (DPH), an antihistamine that also targets serotonin reuptake transporters and the acetylcholine receptor. 72 h studies were conducted at 1–4, 4–7 and 7–10 dpf, followed by behavioral observations using a ViewPoint system at 4, 7 and 10 dpf. Distance traveled and swimming speeds were quantified; nominal treatment levels were analytically verified by isotope-dilution LC–MSMS. Larval zebrafish locomotion displayed significantly different (p < 0.05) activity profiles over the course of typical daylight and

  9. Age matters: Developmental stage of Danio rerio larvae influences photomotor response thresholds to diazinion or diphenhydramine

    Energy Technology Data Exchange (ETDEWEB)

    Kristofco, Lauren A. [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States); Cruz, Luis Colon [Department of Anatomy and Neurobiology, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan (Puerto Rico); Haddad, Samuel P. [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States); Behra, Martine L. [Department of Anatomy and Neurobiology, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan (Puerto Rico); Chambliss, C. Kevin [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States); Department of Chemistry, Baylor University, Waco, TX (United States); Brooks, Bryan W., E-mail: Bryan_Brooks@baylor.edu [Department of Environmental Science, Center for Reservoir and Aquatic Systems Research, Baylor University, Waco, TX (United States)

    2016-01-15

    Highlights: • Fish behavior impairments by biological active contaminants are limited yet necessary. • Aquatic toxicology assays with 0–4 dpf larval zebrafish are increasingly important. • Larval zebrafish locomotion varied with age and daylight during typical workday hours. • Photomotor behavior to diazinion and diphenhydramine differed by larval zebrafish age. • Behavioral responses of 7–10 dpf zebrafish were markedly more sensitive than 0–4 dpf. - Abstract: Because basic toxicological data is unavailable for the majority of industrial compounds, High Throughput Screening (HTS) assays using the embryonic and larval zebrafish provide promising approaches to define bioactivity profiles and identify potential adverse outcome pathways for previously understudied chemicals. Unfortunately, standardized approaches, including HTS experimental designs, for examining fish behavioral responses to contaminants are rarely available. In the present study, we examined movement behavior of larval zebrafish over 7 days (4–10 days post fertilization or dpf) during typical daylight workday hours to determine whether intrinsic activity differed with age and time of day. We then employed an early life stage approach using the Fish Embryo Test (FET) at multiple developmental ages to evaluate whether photomotor response (PMR) behavior differed with zebrafish age following exposure to diazinon (DZN), a well-studied orthophosphate insecticide, and diphenhydramine (DPH), an antihistamine that also targets serotonin reuptake transporters and the acetylcholine receptor. 72 h studies were conducted at 1–4, 4–7 and 7–10 dpf, followed by behavioral observations using a ViewPoint system at 4, 7 and 10 dpf. Distance traveled and swimming speeds were quantified; nominal treatment levels were analytically verified by isotope-dilution LC–MSMS. Larval zebrafish locomotion displayed significantly different (p < 0.05) activity profiles over the course of typical daylight and

  10. Characterization of transcriptome in the Indian meal moth Plodia interpunctella (Lepidoptera: Pyralidae) and gene expression analysis during developmental stages.

    Science.gov (United States)

    Tang, Pei-An; Wu, Hai-Jing; Xue, Hao; Ju, Xing-Rong; Song, Wei; Zhang, Qi-Lin; Yuan, Ming-Long

    2017-07-30

    The Indian meal moth Plodia interpunctella (Lepidoptera: Pyralidae) is a worldwide pest that causes serious damage to stored foods. Although many efforts have been conducted on this species due to its economic importance, the study of genetic basis of development, behavior and insecticide resistance has been greatly hampered due to lack of genomic information. In this study, we used high throughput sequencing platform to perform a de novo transcriptome assembly and tag-based digital gene expression profiling (DGE) analyses across four different developmental stages of P. interpunctella (egg, third-instar larvae, pupae and adult). We obtained approximate 9gigabyte (GB) of clean data and recovered 84,938 unigenes, including 37,602 clusters and 47,336 singletons. These unigenes were annotated using BLAST against the non-redundant protein databases and then functionally classified based on Gene Ontology (GO), Clusters of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes databases (KEGG). A large number of differentially expressed genes were identified by pairwise comparisons among different developmental stages. Gene expression profiles dramatically changed between developmental stage transitions. Some of these differentially expressed genes were related to digestion and cuticularization. Quantitative real-time PCR results of six randomly selected genes conformed the findings in the DGEs. Furthermore, we identified over 8000 microsatellite markers and 97,648 single nucleotide polymorphisms which will be useful for population genetics studies of P. interpunctella. This transcriptomic information provided insight into the developmental basis of P. interpunctella and will be helpful for establishing integrated management strategies and developing new targets of insecticides for this serious pest. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Altered developmental timing in early life stages of Antarctic krill (Euphausia superba) exposed to p,p'-DDE

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Anita H., E-mail: anita.poulsen@uq.edu.au [The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd, Brisbane, Qld 4108 (Australia); Kawaguchi, So, E-mail: so.kawaguchi@aad.gov.au [Australian Antarctic Division, Channel Highway, Kingston, Tas 7050 (Australia); Leppaenen, Matti T., E-mail: matti.t.leppanen@uef.fi [University of Eastern Finland, Joensuu Campus, Department of Biology, FIN-80101 (Finland); Kukkonen, Jussi V.K., E-mail: jussi.kukkonen@uef.fi [University of Eastern Finland, Joensuu Campus, Department of Biology, FIN-80101 (Finland); Bengtson Nash, Susan M., E-mail: s.bengtsonnash@griffith.edu.au [The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd, Brisbane, Qld 4108 (Australia); Griffith University, Atmospheric Environment Research Centre, Brisbane, Qld 4111 (Australia)

    2011-11-15

    Persistent organic pollutants (POPs) are persistent, toxic and bioaccumulative anthropogenic organic chemicals, capable of undergoing long range environmental transport to remote areas including the Antarctic. p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE) has been identified as a dominant POP accumulating in Antarctic krill (Euphausia superba), which is a key Southern Ocean species. This study examined the developmental toxicity of p,p'-DDE via aqueous exposure to Antarctic krill larvae. p,p'-DDE exposure was found to stimulate developmental timing in the first three larval stages of Antarctic krill, while extended monitoring of larvae after a five day exposure period had ended, revealed delayed inhibitory responses during development to the fourth larval stage. Stimulatory responses were observed from the lowest p,p'-DDE body residue tested of 10.1 {+-} 3.0 {mu}mol/kg (3.2 {+-} 0.95 mg/kg) preserved wet weight, which is comparable to findings for temperate species and an order of magnitude lower than the exposure level found to cause sublethal behavioural effects in Antarctic krill. The delayed responses included increased mortality, which had doubled in the highest p,p'-DDE treatment (95 {+-} 8.9% mortality at 20 {mu}g/L p,p'-DDE) compared to the solvent control (44 {+-} 11% mortality) 2 weeks after end of exposure. Development of surviving metanauplius larvae to calyptopis 1 larvae was delayed by 2 days in p,p'-DDE exposed larvae compared with untreated larvae. Finally, the developmental success of surviving p,p'-DDE exposed larvae was reduced by 50 to 75% compared to the solvent control (100% developmental success). The lowest observed effect concentration for all delayed effects was 1 {mu}g/L, the lowest exposure concentration tested. These findings demonstrate the importance of delayed and indirect effects of toxicant exposure. Further, the findings of this study are important for environmental risk assessment

  12. Sensitivity of hiPSC-derived neural stem cells (NSC) to Pyrroloquinoline quinone depends on their developmental stage.

    Science.gov (United States)

    Augustyniak, J; Lenart, J; Zychowicz, M; Lipka, G; Gaj, P; Kolanowska, M; Stepien, P P; Buzanska, L

    2017-12-01

    Pyrroloquinoline quinone (PQQ) is a factor influencing on the mitochondrial biogenesis. In this study the PQQ effect on viability, total cell number, antioxidant capacity, mitochondrial biogenesis and differentiation potential was investigated in human induced Pluripotent Stem Cells (iPSC) - derived: neural stem cells (NSC), early neural progenitors (eNP) and neural progenitors (NP). Here we demonstrated that sensitivity to PQQ is dependent upon its dose and neural stage of development. Induction of the mitochondrial biogenesis by PQQ at three stages of neural differentiation was evaluated at mtDNA, mRNA and protein level. Changes in NRF1, TFAM and PPARGC1A gene expression were observed at all developmental stages, but only at eNP were correlated with the statistically significant increase in the mtDNA copy numbers and enhancement of SDHA, COX-1 protein level. Thus, the "developmental window" of eNP for PQQ-evoked mitochondrial biogenesis is proposed. This effect was independent of high antioxidant capacity of PQQ, which was confirmed in all tested cell populations, regardless of the stage of hiPSC neural differentiation. Furthermore, a strong induction of GFAP, with down regulation of MAP2 gene expression upon PQQ treatment was observed. This indicates a possibility of shifting the balance of cell differentiation in the favor of astroglia, but more research is needed at this point. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Biogenic volatile organic compound emissions from senescent maize leaves and a comparison with other leaf developmental stages

    Science.gov (United States)

    Mozaffar, A.; Schoon, N.; Bachy, A.; Digrado, A.; Heinesch, B.; Aubinet, M.; Fauconnier, M.-L.; Delaplace, P.; du Jardin, P.; Amelynck, C.

    2018-03-01

    Plants are the major source of Biogenic Volatile Organic Compounds (BVOCs) which have a large influence on atmospheric chemistry and the climate system. Therefore, understanding of BVOC emissions from all abundant plant species at all developmental stages is very important. Nevertheless, investigations on BVOC emissions from even the most widespread agricultural crop species are rare and mainly confined to the healthy green leaves. Senescent leaves of grain crop species could be an important source of BVOCs as almost all the leaves senesce on the field before being harvested. For these reasons, BVOC emission measurements have been performed on maize (Zea mays L.), one of the most cultivated crop species in the world, at all the leaf developmental stages. The measurements were performed in controlled environmental conditions using dynamic enclosures and proton transfer reaction mass spectrometry (PTR-MS). The main compounds emitted by senescent maize leaves were methanol (31% of the total cumulative BVOC emission on a mass of compound basis) and acetic acid (30%), followed by acetaldehyde (11%), hexenals (9%) and m/z 59 compounds (acetone/propanal) (7%). Important differences were observed in the temporal emission profiles of the compounds, and both yellow leaves during chlorosis and dry brown leaves after chlorosis were identified as important senescence-related BVOC sources. Total cumulative BVOC emissions from senescent maize leaves were found to be among the highest for senescent Poaceae plant species. BVOC emission rates varied strongly among the different leaf developmental stages, and senescent leaves showed a larger diversity of emitted compounds than leaves at earlier stages. Methanol was the compound with the highest emissions for all the leaf developmental stages and the contribution from the young-growing, mature, and senescent stages to the total methanol emission by a typical maize leaf was 61, 13, and 26%, respectively. This study shows that BVOC

  14. Effect of stage of follicular growth during superovulation on developmental competence of bovine oocytes

    DEFF Research Database (Denmark)

    Humblot, P; Holm, Peter; Lonergan, P

    2005-01-01

    . Follicular characteristics were measured and oocyte quality was assessed by morphology, mRNA expression of eight marker genes or developmental ability after in vitro/in vivo maturation and subsequent in vitro fertilization and culture. Approaching ovulation, expected increases in follicular size and cumulus...... expansion suggested progression of oocyte maturation. No differences were found in the expression patterns of analyzed genes, except for heat-shock-protein (Hsp) that was lower in in vivo matured oocytes collected shortly before ovulation. Oocytes collected at this time also had higher developmental ability...... measured as blastocyst rates (57.6 after in vitro production while no differences were found between oocytes recovered earlier at the first three time points (39.3-41.5. We conclude that oocytes recovered late in the preovulatory period are more developmentally competent than oocytes recovered at the pre...

  15. Developmental Arrest at the Logographic Stage: Impaired Literacy Functions in Klinefelter's XXXY Syndrome.

    Science.gov (United States)

    Seymour, Philip H. K.; Evans, Henryka M.

    1988-01-01

    Reports a case study of the reading and spelling processes of a developmentally disabled child indicating that there was almost a complete lack of alphabetic functions, that reading appeared to be based on a "logographic lexicon," and that spelling was based on a letter sequence generator. (RS)

  16. "Intermetamorphic" developmental stages in 150 million-year-old achelatan lobsters--The case of the species tenera Oppel, 1862.

    Science.gov (United States)

    Haug, Joachim T; Haug, Carolin

    2016-03-01

    We re-investigated the fossil species tenera Oppel, 1862, an achelatan lobster (traditionally named Palinurina tenera) found in 150 million years old limestones of southern Germany. All known specimens attributed to this species show a mixture of characters, which in modern forms occur either in larvae or post-larval juveniles. Hence these specimens provide insight into a phase in ontogeny that is no longer present in the developmental sequence of any modern achelatan lobster, as the latter ones skip this phase and replace it by a drastic metamorphosis. Comparable cases have been described earlier, yet did only comprise single stages or two successive ones at most. In the here described case four developmental stages are preserved. The reconstructed ontogeny of tenera therefore represents the currently best known sequence of an early achelatan lobster that covers this specific intermediate phase. The largest known stage most likely still represents an immature of a yet undiscovered adult. These findings support the interpretation that early achelatan lobsters developed in a more gradual ontogenetic sequence than modern forms. It furthermore demonstrates that it was even more gradual than anticipated previously. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Three-dimensional visualisation of developmental stages of an apicomplexan fish blood parasite in its invertebrate host

    Directory of Open Access Journals (Sweden)

    Hayes Polly M

    2011-11-01

    Full Text Available Abstract Background Although widely used in medicine, the application of three-dimensional (3D imaging to parasitology appears limited to date. In this study, developmental stages of a marine fish haemogregarine, Haemogregarina curvata (Apicomplexa: Adeleorina, were investigated in their leech vector, Zeylanicobdella arugamensis; this involved 3D visualisation of brightfield and confocal microscopy images of histological sections through infected leech salivary gland cells. Findings 3D assessment demonstrated the morphology of the haemogregarine stages, their spatial layout, and their relationship with enlarged host cells showing reduced cellular content. Haemogregarine meronts, located marginally within leech salivary gland cells, had small tail-like connections to the host cell limiting membrane; this parasite-host cell interface was not visible in two-dimensional (2D light micrographs and no records of a similar connection in apicomplexan development have been traced. Conclusions This is likely the first account of the use of 3D visualisation to study developmental stages of an apicomplexan parasite in its invertebrate vector. Elucidation of the extent of development of the haemogregarine within the leech salivary cells, together with the unusual connections between meronts and the host cell membrane, illustrates the future potential of 3D visualisation in parasite-vector biology.

  18. Studies on the effect of gamma irradiation on the different developmental stages of mediterranean flour moth ephestia kuehniella (ZELL)

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Baky, S M

    1981-12-31

    The effect of gamma radiation for controlling insects in grain and grain products appear to have some advantages over conventional control methods. The main advantages of gamma radiation is that, it is quick and completely effective when used in proper doses, no chemical residues on the treated commodity and also no undesirable changes in irradiated food.The objective of this study was to investigate the effects of gamma irradiation on E. kuehniella which is considered one of the most important insects in egypt. A-Effect of gamma irradiation on different developmental stages of E. kuehniella. B- Effect of gamma irradiation on mating competitiveness. 14 tabs., 10 figs., 97 refs.

  19. The association of Tarsonemus mites (Acari: Heterostigmata) with different apple developmental stages and apple core rot diseases

    OpenAIRE

    Ueckermann, Edward Albert; Van der Walt, Lené; Spotts, Robert A.; Smit, Francois J.; Jensen, Tamaryn; McLeod, Adéle

    2011-01-01

    Information on the role of mites in the genus Tarsonemus Canestrini and Fanzago, 1876 in the epidemiology of apple core rots (wet and dry) is limited. The aims of this study were to (1) assess the effect of different apple developmental stages (buds, blossoms, 4-cm diameter fruit, mature fruit and mummies) on the relative abundance of Tasonemus mites, (2) determine if there is a tendency of Tarsonemus mites to be associated with wet core rot (WCR) and dry core rot (DCR) apples, and (3) evalua...

  20. Lettuce facing microcystins-rich irrigation water at different developmental stages: Effects on plant performance and microcystins bioaccumulation.

    Science.gov (United States)

    Levizou, Efi; Statiris, George; Papadimitriou, Theodoti; Laspidou, Chrysi S; Kormas, Konstantinos Ar

    2017-09-01

    This study investigated the microcystins (MCs)-rich irrigation water effect on lettuce of different developmental stages, i.e. during a two months period, covering the whole period from seed germination to harvest at marketable size of the plant. We followed four lettuce plant groups receiving MCs-rich water (1.81μgl -1 of dissolved MCs), originating from the Karla Reservoir, central Greece: 1) from seeds, 2) the cotyledon, 3) two true leaves and 4) four true leaves stages, all of which were compared to control plants that received tap water. Lettuce growth, photosynthetic performance, biochemical and mineral characteristics, as well as MCs accumulation in leaves, roots and soil were measured. The overall performance of lettuce at various developmental stages pointed to increased tolerance since growth showed minor alterations and non-enzymatic antioxidants remained unaffected. Plants receiving MCs-rich water from the seed stage exhibited higher photosynthetic capacity, chlorophylls and leaf nitrogen content. Nevertheless, considerable MCs accumulation in various plant tissues occurred. The earlier in their development lettuce plants started receiving MCs-rich water, the more MCs they accumulated: roots and leaves of plants exposed to MCs-rich water from seeds and cotyledons stage exhibited doubled MCs concentrations compared to respective tissues of the 4 Leaves group. Furthermore, roots accumulated significantly higher MCs amounts than leaves of the same plant group. Concerning human health risk, the Estimated Daily Intake values (EDI) of Seed and Cotyledon groups leaves exceeded Tolerable Daily Intake (TDI) by a factor of 6, while 2 Leaves and 4 Leaves groups exceeded TDI by a factor of 4.4 and 2.4 respectively. Our results indicate that irrigation of lettuce with MCs-rich water may constitute a serious public health risk, especially when contaminated water is received from the very early developmental stages (seed and cotyledon). Finally, results obtained for

  1. Translocation and distribution of 14C-photoassimilates in strawberry plants varying in developmental stages of the inflorescence

    International Nuclear Information System (INIS)

    Nishizawa, T.; Hori, Y.

    1988-01-01

    Translocation and distribution of photo-assimilates in strawberry plants were studied by pules-feeding 14CO2 at different developmental stages of inflorescence.1. After feeding the largest leaf at the fruit coloring stage, there were distinguished a rapid phase of about 6 hours and a subsequent slow phase in 14C export on the basis of 14C recovered. The current export was terminated about 16 hours after feeding with a percentage value of 50, about 90% of which was distributed in the berries.2. When all the leaves were fed, the total export to plant parts other than leaves increased from around 20% after feedings at and before flowering to 52% after feeding at the coloring stage of the 14C exported, about 40% was found in the roots and only 20% in the flowers after feedings at and before flowering. After later feedings, the distribution to the roots decreased and that to the berries increased gradually, reaching 86% at the coloring stage.3. Within an inflorescence, distribution to the receptacle increased from 70% after feeding at the budding stage to 89% after the coloring stage, although it decreased to 30% temporarily after feeding at the growing stage. Corresponding to this decrease, distribution to the achenes increased to 68% but soon decreased to 9% after feeding at the coloring stage.4. Within an inflorescence, there was recognized competition for 14C assimilates among flowers; this was especially true between the primary and tertiary flowers.5. In individual flowers, sink activity decreased, though temporarily, near flowering. This flowering of sink activity seemed to be intrinsic, and should be distinguished from lowering by competition (with other flowers)

  2. Evaluation of lysozyme, complement C3, and total protein in different developmental stages of Caspian kutum (Rutilus frisii kutum K.

    Directory of Open Access Journals (Sweden)

    Abdollahi Razieh

    2016-03-01

    Full Text Available In this study, non–specific immune parameters in fertilized eggs, eyed embryos, larvae 10, 25, 50, 60, and 70 days post hatch (DPH, and female broodstock of Caspian kutum, Rutilus frisii kutum (Kamensky, were evaluated. The lysozyme activity, complement C3, and total protein levels were measured with the turbidimetric, immunoturbidimetric, and Bradford methods, respectively. The results showed that lysozyme levels decreased from levels noted in the fertilized eggs until the larvae were 10 days old. Subsequently, significant increases in lysozyme levels were observed until 70 DPH. An increasing trend of complement component C3 was noted from the levels in fertilized eggs to 10 DPH, following which it decreased significantly. Total protein levels differed significantly in early developmental stages of Caspian kutum. The higher values of complement component C3 than of lysozyme in the early life stages could be indicative of the former’s more fundamental role.

  3. Effect of ovary induction on bread wheat anther culture: ovary genotype and developmental stage, and candidate gene association.

    Directory of Open Access Journals (Sweden)

    Ana María Castillo

    2015-06-01

    Full Text Available Ovary pre-conditioned medium and ovary co-culture increased the efficiency of green doubled haploid plant production in bread wheat anther culture. The positive effect of this medium led to a 6- and 11-fold increase in the numbers of embryos and green plants, respectively, having a greater effect on a medium-low responding cultivar. Ovary genotype and developmental stage significantly affected microspore embryogenesis. By he use of Caramba ovaries it was possible to reach a 2-fold increase in the number of embryos and green plants, and to decrease the rate of albinism. Mature ovaries from flowers containing microspores at a late binucleate stage raised the number of embryos and green plants by 25% and 46% as compared to immature ovaries (excised from flowers with microspores at a mid-late uninucleate stage. The highest numbers of embryos and green plants were produced when using mature Caramba ovaries. Ovaries from Galeón, Tigre and Kilopondio cultivars successfully induced microspore embryogenesis at the same rate as Caramba ovaries. Moreover, Tigre ovaries raised the percentage of spontaneous chromosome doubling up to 71%. Attempts were made to identify molecular mechanisms associated to the inductive effect of the ovaries on microspore embryogenesis. The genes TAA1b, FLA26 and WALI6 associated to wheat microspore embryogenesis, the CGL1 gene involved in glycan biosynthesis or degradation, and the FER gene involved in the ovary signalling process were expressed and/or induced at different rates during ovary culture. The expression pattern of FLA26 and FER could be related to the differences between genotypes and developmental stages in the inductive effect of the ovary. Our results open opportunities for new approaches to increase bread wheat doubled haploid production by anther culture, and to identify the functional components of the ovary inductive effect on microspore embryogenesis.

  4. Dental age estimation from the developmental stage of the third molars in western Chinese population.

    Science.gov (United States)

    Li, Guo; Ren, Jiayin; Zhao, Shuping; Liu, Yuanyuan; Li, Na; Wu, Wanhong; Yuan, Shanshan; Wang, Hu

    2012-06-10

    The purpose of this study is to provide reference data about estimating dental age from third molars of the western Chinese population for comparing with other populations and being applied to the age estimation of western Chinese juveniles and adolescents. A total of 2078 digital panoramic radiographs of 989 male and 1089 female Chinese subjects aged between 5 and 23 years were examined. The mineralization status of the third molars was assessed using the formation stages described by Demirjian et al. with two modifications. The results showed that the development of third molars in the western Chinese population was likely to begin at age 5 in both males and females. The third molars 28 and 48 showed significantly higher frequency in females than in males. The third molars 18 in the stage 1, 38 in the stages 1, A and G, and 48 in the stage H showed significantly older average age in females than in males. The Demirjian's stages C and D could be used as a reference stage to determine dichotomously whether a western Chinese is more likely to be under or above age 14 or 16, respectively. This study provided reference data for the age estimation of western Chinese juveniles and adolescents by the mineralization stages of the third molar. Apart from forensic age determination in living subjects, the presented reference data can also be used for age estimations of unidentified corpses and skeletons. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Early-stage valuation of medical devices: the role of developmental uncertainty.

    Science.gov (United States)

    Girling, Alan; Young, Terry; Brown, Celia; Lilford, Richard

    2010-08-01

    At the concept stage, many uncertainties surround the commercial viability of a new medical device. These include the ultimate functionality of the device, the cost of producing it and whether, and at what price, it can be sold to a health-care provider (HCP). Simple assessments of value can be made by estimating such unknowns, but the levels of uncertainty may mean that their operational value for investment decisions is unclear. However, many decisions taken at the concept stage are reversible and will be reconsidered later before the product is brought to market. This flexibility can be exploited to enhance early-stage valuations. To develop a framework for valuing a new medical device at the concept stage that balances benefit to the HCP against commercial costs. This is done within a simplified stage-gated model of the development cycle for new products. The approach is intended to complement existing proposals for the evaluation of the commercial headroom available to new medical products. A model based on two decision gates can lead to lower bounds (underestimates) for product value that can serve to support a decision to develop the product. Quantifiable uncertainty that can be resolved before the device is brought to market will generally enhance early-stage valuations of the device, and this remains true even when some components of uncertainty cannot be fully described. Clinical trials and other evidence-gathering activities undertaken as part of the development process can contribute to early-stage estimates of value.

  6. Influence of mycorrhizal developmental stages and plant age on rhizosphere mycoflora of Pinus kesiya (Royle

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    G. D. Sharma

    2014-08-01

    Full Text Available Quantitatively the population was recorded to be high around thc mycorrhizal roots. Some fungi were specific to different stages of mycorrhizal development. Rhizopus nigricans and Cunninghamella elegans were recorded at 5% mycorrhizal association stage. Fusarium sp. was found at 20% mycorrhizal association, while Mucor spp. were obtained at 60% stage. Verticillium sp. had the highest frequency of occurrence in the beginning of mycorrhizal association but later on Penicilium spp. were found to be the most common. Sugar content of mycorrhizal and nonmycorrhizal roots were determined to assess their effect on the mycorrhizospheric micropopulation. The mannitol and trehalose were present only in mycorrhizal roots.

  7. Sensitivity of the different developmental stages of Callosobruchus maculatus to gamma irradiation

    International Nuclear Information System (INIS)

    Olaifa, J.I.; Adebayo, T.A.; Adesanmi, C.A.; Salau, A.M.

    1990-01-01

    Life stages of the cowpea seed beetle (Callosobruchus maculatus F.) were γ irradiated from a 60 Co source. Arrested development was observed at dosages of 1.0, 4.0, 10.0 and 10.0 Gy in the egg, 1st, 2nd, 3rd and 4th larvae stages respectively while 4.0 Gy induced sterility. Longevity of 2-day old adults was not affected by irradiation of 100 Gy. Preservation of cowpeas by irradiation is discussed. (author)

  8. The Developmental Stage of Adult Human Stem Cell-Derived Retinal Pigment Epithelium Cells Influences Transplant Efficacy for Vision Rescue

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    Richard J. Davis

    2017-07-01

    Full Text Available Age-related macular degeneration (AMD is a common cause of central visual loss in the elderly. Retinal pigment epithelial (RPE cell loss occurs early in the course of AMD and RPE cell transplantation holds promise to slow disease progression. We report that subretinal transplantation of RPE stem cell (RPESC-derived RPE cells (RPESC-RPE preserved vision in a rat model of RPE cell dysfunction. Importantly, the stage of differentiation that RPESC-RPE acquired prior to transplantation influenced the efficacy of vision rescue. Whereas cells at all stages of differentiation tested rescued photoreceptor layer morphology, an intermediate stage of RPESC-RPE differentiation obtained after 4 weeks of culture was more consistent at vision rescue than progeny that were differentiated for 2 weeks or 8 weeks of culture. Our results indicate that the developmental stage of RPESC-RPE significantly influences the efficacy of RPE cell replacement, which affects the therapeutic application of these cells for AMD.

  9. Quantitative proteomics links metabolic pathways to specific developmental stages of the plant-pathogenic oomycete Phytophthora capsici.

    Science.gov (United States)

    Pang, Zhili; Srivastava, Vaibhav; Liu, Xili; Bulone, Vincent

    2017-04-01

    The oomycete Phytophthora capsici is a plant pathogen responsible for important losses to vegetable production worldwide. Its asexual reproduction plays an important role in the rapid propagation and spread of the disease in the field. A global proteomics study was conducted to compare two key asexual life stages of P. capsici, i.e. the mycelium and cysts, to identify stage-specific biochemical processes. A total of 1200 proteins was identified using qualitative and quantitative proteomics. The transcript abundance of some of the enriched proteins was also analysed by quantitative real-time polymerase chain reaction. Seventy-three proteins exhibited different levels of abundance between the mycelium and cysts. The proteins enriched in the mycelium are mainly associated with glycolysis, the tricarboxylic acid (or citric acid) cycle and the pentose phosphate pathway, providing the energy required for the biosynthesis of cellular building blocks and hyphal growth. In contrast, the proteins that are predominant in cysts are essentially involved in fatty acid degradation, suggesting that the early infection stage of the pathogen relies primarily on fatty acid degradation for energy production. The data provide a better understanding of P. capsici biology and suggest potential metabolic targets at the two different developmental stages for disease control. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  10. Developmental-stage-dependent radiosensitivity of neural cells in the ventricular zone of telencephalon in mouse and rat fetuses

    International Nuclear Information System (INIS)

    Hoshino, K.; Kameyama, Y.

    1988-01-01

    Pregnant ICR mice were treated with single whole-body X-radiation at a dose of 0.24 Gy on day 10, 13, or 15 of gestation. Fetuses were obtained from mothers during 1 and 24 hours after irradiation. Pyknotic cells in the ventricular zone of telencephalon were counted in serial histological sections. Incidence of pyknotic cells peaked during 6 and 9 hours after irradiation in each gestation day group. Then, dose-response curves were obtained 6 hours after 0-0.48 Gy of irradiation. All three dose-response curves showed clear linearity in the dose range lower than 0.24 Gy. Ratios of radiosensitivity estimated from the slopes of dose-response curves in day 10, 13, and 15 groups were 1, 1.4, and 0.4, respectively. These demonstrated that ventricular cells in the day 13 fetal telencephalon were the most radiosensitive among the three different age groups. In order to confirm the presence of the highly radiosensitive stage common to mammalian cerebral cortical histogenesis, pregnant F344 rats were treated with single whole-body gamma-irradiation at a dose of 0.48 Gy on day 13, 14, 15, 17, or 19 of gestation. The incidence of pyknotic cells in the ventricular zone of telencephalon was examined microscopically during 1 and 24 hours after irradiation. The peak incidence was shown 6 hours after irradiation in all the treated groups, and the highest peak incidence was shown in day-15-treated group. The developmental stage of telencephalon of day 15 rat fetuses was comparable to that of day 13 mouse fetuses. Thus, the highest radiosensitivity in terms of acute cell death was shown in the same developmental stage of brain development, i.e., the beginning phase of cerebral cortical histogenesis, in both mice and rats

  11. Immature stages of Spodoptera eridania (Lepidoptera: Noctuidae): developmental parameters and host plants.

    Science.gov (United States)

    Montezano, Débora Goulart; Specht, Alexandre; Sosa-Gómez, Daniel Ricardo; Roque-Specht, Vânia Ferreira; de Barros, Neiva Monteiro

    2014-01-01

    This study aimed to detail the temporal and morphological parameters of the immature stages of southern armyworm Spodoptera eridania (Stoll, 1782) with larvae feed on artificial diet, under controlled conditions (25 ± 1°C, 70 ± 10% relative humidity and 14-h photophase) and gather information about their larval host plants. The viability of the egg, larval, pupal, and prepupal stages was 97.82, 93.62, 96.42, and 97.03%, respectively. The average duration of the egg, larval, pupal, and pre-pupal stages was 4.00, 16.18, 1.58, and 9.17 d, respectively. During the larval stage, 43.44% of females passed through seven instars, observing that the female's development was significant slower than males. The female larvae that developed through six and seven instars exhibited a mean growth rate of 1.52 and 1.44, respectively. Female pupae were significantly larger, exhibiting faster development than males. The rearing method proved to be adequate, providing more detailed observations of the biological cycle, especially at the larval stage, and resulting in an overall survival of almost 85%. Two hundred two plant species belonging to 58 families are listed as natural hosts for S. eridania, mainly including Asteraceae, Fabaceae, Solanaceae, Poaceae, Amaranthaceae, and Malvaceae. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  12. Validation of reference genes for quantitative real-time PCR in Périgord black truffle (Tuber melanosporum) developmental stages.

    Science.gov (United States)

    Zarivi, Osvaldo; Cesare, Patrizia; Ragnelli, Anna Maria; Aimola, Pierpaolo; Leonardi, Marco; Bonfigli, Antonella; Colafarina, Sabrina; Poma, Anna Maria; Miranda, Michele; Pacioni, Giovanni

    2015-08-01

    The symbiotic fungus Tuber melanosporum Vittad. (Périgord black truffle) belongs to the Ascomycota and forms mutualistic symbiosis with tree and shrub roots. This truffle has a high value in a global market and is cultivated in many countries of both hemispheres. The publication of the T. melanosporum genome has given researchers unique opportunities to learn more about the biology of the fungus. Real-time quantitative PCR (qRT-PCR) is a definitive technique for quantitating differences in transcriptional gene expression levels between samples. To facilitate gene expression studies and obtain more accurate qRT-PCR data, normalization relative to stable housekeeping genes is required. These housekeeping genes must show stable expression under given experimental conditions for the qRT-PCR results to be accurate. Unfortunately, there are no studies on the stability of housekeeping genes used in T. melanosporum development. In this study, we present a morphological and microscopical classification of the developmental stages of T. melanosporum fruit body, and investigate the expression levels of 12 candidate reference genes (18S rRNA; 5.8S rRNA; Elongation factor 1-alpha; Elongation factor 1-beta; α-tubulin; 60S ribosomal protein L29; β-tubulin; 40S ribosomal protein S1; 40S ribosomal protein S3; Glucose-6-phosphate dehydrogenase; β-actin; Ubiquitin-conjugating enzyme). To evaluate the suitability of these genes as endogenous controls, five software-based approaches and one web-based comprehensive tool (RefFinder) were used to analyze and rank the tested genes. We demonstrate here that the 18S rRNA gene shows the most stable expression during T. melanosporum development and that a set of three genes, 18S rRNA, Elongation factor 1-alpha and 40S ribosomal protein S3, is the most suitable to normalize qRT-PCR data from all the analyzed developmental stages; conversely, 18S rRNA, Glucose-6-phosphate dehydrogenase and Elongation factor 1-alpha are the most suitable

  13. Antecedents of Adolescent Initiation into Stages of Drug Use: A Developmental Analysis

    Science.gov (United States)

    Kandel, Denise B.; And Others

    1978-01-01

    Predictors associated with adolescents' initiation into three cumulative stages of drug use--hard liquor, marihuana, and other illicit drugs--were investigated. The strongest predictors were prior involvement in deviant behavior (hard liquor); peer influence, and adolescent beliefs and values (marihuana); and relationship to parents, and…

  14. Outcome of one-stage treatment of developmental dysplasia of hip in older children

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    Basant Kumar Bhuyan

    2012-01-01

    Conclusions: Young children having DDH can safely be treated with an extensive one-stage triple procedure of open reduction, femoral shortening derotation, and Salter′s osteotomy, without increasing the risk of AVN. Early diagnosis and intervention is the successful treatment of patients suffering from DDH.

  15. A Project to Help Child Development Students Recognize Piagetian Developmental Stages.

    Science.gov (United States)

    Husmann, Ann

    This practicum report was designed to help child development students differentiate between the preoperational and concrete operational stages of the Piagetian cognitive hierarchy. The 36 on-campus and 63 instructional television students used a Piagetian Game booklet, which is included in the appendix. Using this booklet, students were able to…

  16. Plant and Floret Growth at Distinct Developmental Stages During the Stem Elongation Phase in Wheat

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    Zifeng Guo

    2018-03-01

    Full Text Available Floret development is critical for grain setting in wheat (Triticum aestivum, but more than 50% of grain yield potential (based on the maximum number of floret primordia is lost during the stem elongation phase (SEP, from the terminal spikelet stage to anthesis. Dynamic plant (e.g., leaf area, plant height and floret (e.g., anther and ovary size growth and its connection with grain yield traits (e.g., grain number and width are not clearly understood. In this study, for the first time, we dissected the SEP into seven stages to investigate plant (first experiment and floret (second experiment growth in greenhouse- and field-grown wheat. In the first experiment, the values of various plant growth trait indices at different stages were generally consistent between field and greenhouse and were independent of the environment. However, at specific stages, some traits significantly differed between the two environments. In the second experiment, phenotypic and genotypic similarity analysis revealed that grain number and size corresponded closely to ovary size at anthesis, suggesting that ovary size is strongly associated with grain number and size. Moreover, principal component analysis (PCA showed that the top six principal components PCs explained 99.13, 98.61, 98.41, 98.35, and 97.93% of the total phenotypic variation at the green anther, yellow anther, tipping, heading, and anthesis stages, respectively. The cumulative variance explained by the first PC decreased with floret growth, with the highest value detected at the green anther stage (88.8% and the lowest at the anthesis (50.09%. Finally, ovary size at anthesis was greater in wheat accessions with early release years than in accessions with late release years, and anther/ovary size shared closer connections with grain number/size traits at the late vs. early stages of floral development. Our findings shed light on the dynamic changes in plant and floret growth-related traits in wheat and the

  17. Influence of Alternate Bearing on Leaf and Fruit Mineral Composition at Different Developmental Stages of Date Palm Fruits

    Directory of Open Access Journals (Sweden)

    M.O. El-Mardi

    2005-01-01

    Full Text Available Samples of leaflets and fruits at different stages were collected from 6 “on-palms” and 6 “off-palms” (15-16 years of the Fard Cultivar. Samples were dried, ashed and digested. Macro and micronutrient concentrations of K, Ca, Mg,Na, Fe, Zn, Cu and Mg were determined by ICP-AES and N was measured by Kjeldhal method. Significant changes in the elemental concentrations of leaf and fruit occurred between Kimri (green color and Bisir (yellowish-red color development stages. Potassium and Mg concentration was reduced in leaf and fruit. Calcium and Na were reduced in the fruit and increased in the leaf. Iron, Zn and Mn were not significantly different between Bisir and Kimi. However, Fe in the fruit and leaf increased between Kimri and Bisir and decreased from Bisir to Rutab stages. The concentration of Ca, Mg, Fe and Mn was higher in the leaf than fruit. In contrast K, Zn and Cu were higher in the fruit. Higher Ca and Mg in leaves through the developmental stages were associated with higher concentration of K in the fruit than the leaf. These variations in the leaf and fruit elemental concentration were associated with physiological and biochemical changes during fruit development. Significant differences in the fruit elemental concentrations between the “on” (high yield producing and “off” (low yield producing palms during the developmental stages were in Ca, K, Mn and Fe and in the leaf in Mg and K. However, the general trend during Rutab (honey color, soft tissue indicates that “off-palm” leaves have higher N, Ca, Mg, Fe, Zn, Cu and Mn than “on-palm” leaves. Potassium and Na were higher in the “on-palm” leaves than “off-palm” leaves. But in the fruit, Rutab Ca, Mg, Fe, and Zn content followed similar trends as in the “off-palm” leaves; in contrast to leaves, K and Na were higher in “off-palms” fruits and Cu and Mn higher in “on-palm” fruits. The results indicate the need for further research.

  18. K-Cl Cotransporter 2-mediated Cl- Extrusion Determines Developmental Stage-dependent Impact of Propofol Anesthesia on Dendritic Spines.

    Science.gov (United States)

    Puskarjov, Martin; Fiumelli, Hubert; Briner, Adrian; Bodogan, Timea; Demeter, Kornel; Lacoh, Claudia-Marvine; Mavrovic, Martina; Blaesse, Peter; Kaila, Kai; Vutskits, Laszlo

    2017-05-01

    General anesthetics potentiating γ-aminobutyric acid (GABA)-mediated signaling are known to induce a persistent decrement in excitatory synapse number in the cerebral cortex when applied during early postnatal development, while an opposite action is produced at later stages. Here, the authors test the hypothesis that the effect of general anesthetics on synaptogenesis depends upon the efficacy of GABA receptor type A (GABAA)-mediated inhibition controlled by the developmental up-regulation of the potassium-chloride (K-Cl) cotransporter 2 (KCC2). In utero electroporation of KCC2 was used to prematurely increase the efficacy of (GABAA)-mediated inhibition in layer 2/3 pyramidal neurons in the immature rat somatosensory cortex. Parallel experiments with expression of the inward-rectifier potassium channel Kir2.1 were done to reduce intrinsic neuronal excitability. The effects of these genetic manipulations (n = 3 to 4 animals per experimental group) were evaluated using iontophoretic injection of Lucifer Yellow (n = 8 to 12 cells per animal). The total number of spines analyzed per group ranged between 907 and 3,371. The authors found a robust effect of the developmental up-regulation of KCC2-mediated Cl transport on the age-dependent action of propofol on dendritic spines. Premature expression of KCC2, unlike expression of a transport-inactive KCC2 variant, prevented a propofol-induced decrease in spine density. In line with a reduction in neuronal excitability, the above result was qualitatively replicated by overexpression of Kir2.1. The KCC2-dependent developmental increase in the efficacy of GABAA-mediated inhibition is a major determinant of the age-dependent actions of propofol on dendritic spinogenesis.

  19. Regulation of somatic embryo development in Norway spruce (Picea abies). A molecular approach to the characterization of specific developmental stages

    Energy Technology Data Exchange (ETDEWEB)

    Sabala, I. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Genetics

    1998-12-31

    Embryo development is a complex process involving a set of strictly regulated events. The regulation of these events is poorly understood especially during the early stages of embryo development. Somatic embryos go through the same developmental stages as zygotic embryos making them an ideal model system for studying the regulation of embryo development. We have used embryogenic cultures of Picea abies to study some aspects of the regulation of embryo development in gymnosperms. The bottle neck during somatic embryogenesis is the switch from the proliferation stage to the maturation stage. This switch is initiated by giving somatic embryos a maturation treatment i.e. the embryos are treated with abscisic acid (ABA). Somatic embryos which respond to ABA by forming mature somatic embryos were stimulated to secret a 70 kDa protein, AF70. The af70 gene was isolated and characterised. The expression of the af70 gene was constitutive in embryos but was highly ABA-induced in seedlings. Moreover, expression of this gene was stimulated during cold acclimation of Picea abies seedlings. A full length Picea abies cDNA clone Pa18, encoding a protein with the characteristics of plant lipid transfer proteins (LTPs), was isolated and characterised. The Pa18 gene is constitutively expressed in embryogenic cultures of Picea abies representing different stages of development as well as in nonembryogenic callus and seedlings. In situ hybridization showed that Pa18 gene is expressed in all embryonic cells of proliferating somatic embryos but the expression of the gene in mature somatic and zygotic embryos is restricted to the outer cell layer. Southern blot analysis at different stringencies was consistent with a single gene. An alteration in expression of Pa18 causes disturbance in the formation of the proper outer cell layer in the maturing somatic embryos. In addition to its influence on embryo development the Pa18 gene product also inhibits growth of Agrobacterium tumefaciens 195

  20. Morphometric Analysis of the Developmental Stages and Insecticidal Efficacy of Three Botanical Oils Against Adult Callosobruchus analis

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    Olufemi-Salami Folasade Kemisola

    2017-12-01

    Full Text Available The developmental stages of Callosobruchus analis were observed under laboratory conditions at 28 ± 2 °C and 72 ± 5% relative humidity. The results showed that female C. analis began to lay eggs within 24 hours and have an oviposition period of 8.50 ± 0.70 days and an average of 13.00 ± 0.50 eggs were laid by individual C. analis throughout their lifetime. The mean developmental periods from egg to larva and larva to pupa were observed to be 8.50 ± 0.79 and 4.50 ± 0.70 days, respectively. The unmated bruchids were observed to have lived longer than the mated bruchids as the unmated bruchids lifespan was on average 10.50 ± 0.81 days, as opposed to 2.50 ± 0.75 days for mated females. Adult male C. analis have an average antenna length of 2.96 ± 0.08 mm which is slightly longer than 2.42 ± 0.12 mm on average for female bruchids. The three botanical oil extracts from Capsicum frutescens, Anacardium occidentale and Xylopia aethiopica used at 10.0% concentration were not effective, as none of them resulted in a mortality rate of 50% when recorded 3 days after treatment.

  1. Structural differences in gut bacteria communities in developmental stages of natural populations of Lutzomyia evansi from Colombia's Caribbean coast.

    Science.gov (United States)

    Vivero, Rafael José; Jaramillo, Natalia Gil; Cadavid-Restrepo, Gloria; Soto, Sandra I Uribe; Herrera, Claudia Ximena Moreno

    2016-09-13

    adult stages. Additionally, differences were found in bacterial community structure in fed females, unfed females, males and larvae. The intestinal bacteria detected by PCR-TTGE were Enterobacter cloacae and Bacillus thuringiensis, which were present in different life stages of Lu. evansi, and Burkholderia cenocepacia and Bacillus gibsonii, which were detected only in the larval stage. Wolbachia and Leishmania were not detected in gut samples of Lutzomyia evansi. The analyses conducted using microbiological and molecular approaches indicated significant variations in the bacterial communities associated with the gut of Lu. evansi, depending on the developmental stage and food source. We propose that these elements affect microbial diversity in L. evansi guts and may in turn influence pathogen transmission to humans bitten by this insect.

  2. Metabolomic variation of brassica rapa var. rapa (var. raapstelen) and raphanus sativus l. at different developmental stages

    International Nuclear Information System (INIS)

    Jahangir, M.; Farid, I.B.A.

    2014-01-01

    Brassica rapa (var. raapstelen) and Raphanus sativus (red radish) are being used as food and fodder while also known as model in recent plant research due to the diversity of metabolites as well as genetic resemblance to Arabidopsis. This study explains the change in metabolites (amino acids, organic acids, chlorophyll, carotenoids, tocopherols, ascorbic acid, sucrose, phenylpropanoids and glucosinolates) during plant development. In present study the metabolomic variation in relation to plant growth has been evaluated, for Brassica rapa (var. raapstelen) and red radish (Raphanus sativus) at three different developmental stages. A non-targeted and targeted metabolomic approach by NMR and HPLC in combination with Principal component analysis (PCA) of the data was used to identify phytochemicals being influenced by plant growth. The results lead to the better understanding of metabolic changes during plant development and show the importance of plant age with respect to the metabolomic profile of vegetables. (author)

  3. Cyclic electron flow provides acclimatory plasticity for the photosynthetic machinery under various environmental conditions and developmental stages

    Directory of Open Access Journals (Sweden)

    Marjaana eSuorsa

    2015-09-01

    Full Text Available Photosynthetic electron flow operates in two modes, linear and cyclic. In cyclic electron flow (CEF, electrons are recycled around photosystem I. As a result, a transthylakoid proton gradient (ΔpH is generated, leading to the production of ATP without concomitant production of NADPH, thus increasing the ATP/NADPH ratio within the chloroplast. At least two routes for CEF exist: a PGR5-PGRL1–and a chloroplast NDH-like complex mediated pathway. This review focuses on recent findings concerning the characteristics of both CEF routes in higher plants, with special emphasis paid on the crucial role of CEF in under challenging environmental conditions and developmental stages.

  4. Distribution and abundance by larval developmental stages of Symphurus williamsi (Pleuronectiformes: Cynoglossidae in the Gulf of California

    Directory of Open Access Journals (Sweden)

    Gerardo Aceves-Medina

    2006-06-01

    Full Text Available Distribution and abundance of tonguefish larvae (Symphurus williamsi were analyzed from collections made during ten oceanographic surveys in the Gulf of California between 1984 and 1988. Larvae were found mainly during the summer months and the highest abundances were located in the warmer southern and central regions of the Gulf, but they were scarce in the northern portion. High abundance of preflexion larvae occurred in areas where the sea surface temperature was between 29 and 32°C. Distribution patterns according to developmental stage suggest spatial ontogenic segregation with the early larvae in the ocean area of the central and southern regions of the Gulf. Based on abundance of preflexion larvae as well as on signs of a short egg period of this species, spawns may occur between early and mid summer.

  5. Transcriptome analysis of Sacha Inchi (Plukenetia volubilis L. seeds at two developmental stages

    Directory of Open Access Journals (Sweden)

    Wang Xiaojuan

    2012-12-01

    Full Text Available Abstract Background Sacha Inchi (Plukenetia volubilis L., Euphorbiaceae is a potential oilseed crop because the seeds of this plant are rich in unsaturated fatty acids (FAs. In particular, the fatty acid composition of its seed oil differs markedly in containing large quantities of α-linolenic acid (18C:3, a kind of ω-3 FAs. However, little is known about the molecular mechanisms responsible for biosynthesis of unsaturated fatty acids in the developing seeds of this species. Transcriptome data are needed to better understand these mechanisms. Results In this study, de novo transcriptome assembly and gene expression analysis were performed using Illumina sequencing technology. A total of 52.6 million 90-bp paired-end reads were generated from two libraries constructed at the initial stage and fast oil accumulation stage of seed development. These reads were assembled into 70,392 unigenes; 22,179 unigenes showed a 2-fold or greater expression difference between the two libraries. Using this data we identified unigenes that may be involved in de novo FA and triacylglycerol biosynthesis. In particular, a number of unigenes encoding desaturase for formation of unsaturated fatty acids with high expression levels in the fast oil accumulation stage compared with the initial stage of seed development were identified. Conclusions This study provides the first comprehensive dataset characterizing Sacha Inchi gene expression at the transcriptional level. These data provide the foundation for further studies on molecular mechanisms underlying oil accumulation and PUFA biosynthesis in Sacha Inchi seeds. Our analyses facilitate understanding of the molecular mechanisms responsible for the high unsaturated fatty acids (especially α-linolenic acid accumulation in Sacha Inchi seeds.

  6. Susceptibility of Plodia interpunctella (Lepidoptera: Pyralidae) developmental stages to high temperatures used during structural heat treatments.

    Science.gov (United States)

    Mahroof, R; Subramanyam, B

    2006-12-01

    Heating the ambient air of a whole, or a portion of a food-processing facility to 50 to 60 degrees C and maintaining these elevated temperatures for 24 to 36 h, is an old technology, referred to as heat treatment. There is renewed interest in adopting heat treatments around the world as a viable insect control alternative to fumigation with methyl bromide. There is limited published information on responses of the Indian meal moth, Plodia interpunctella (Hübner), exposed to elevated temperatures typically used during heat treatments. Time-mortality relationships were determined for eggs, fifth-instars (wandering-phase larvae), pupae, and adults of P. interpunctella exposed to five constant temperatures between 44 and 52 degrees C. Mortality of each stage increased with increasing temperature and exposure time. In general, fifth-instars were the most heat-tolerant stage at all temperatures tested. Exposure for a minimum of 34 min at 50 degrees C was required to kill 99% of the fifth-instars. It is proposed that heat treatments aimed at controlling fifth-instars should be able to control all other stages of P. interpunctella.

  7. Comparative antennal transcriptome of Apis cerana cerana from four developmental stages.

    Science.gov (United States)

    Zhao, Huiting; Peng, Zhu; Du, Yali; Xu, Kai; Guo, Lina; Yang, Shuang; Ma, Weihua; Jiang, Yusuo

    2018-03-21

    Apis cerana cerana, an important endemic honey bee species in China, possesses valuable characteristics such as a sensitive olfactory system, good foraging ability, and strong resistance to parasitic mites. Here, we performed transcriptome sequencing of the antenna, the major chemosensory organ of the bee, using an Illumina sequencer, to identify typical differentially expressed genes (DEGs) in adult worker bees of different ages, namely, T1 (1 day); T2 (10 days); T3 (15 days); and T4 (25 days). Surprisingly, the expression levels of DEGs changed significantly between the T1 period and the other three periods. All the DEGs were classified into 26 expression profiles by trend analysis. Selected trend clusters were analyzed, and valuable information on gene expression patterns was obtained. We found that the expression levels of genes encoding cuticle proteins declined after eclosion, while those of immunity-related genes increased. In addition, genes encoding venom proteins and major royal jelly proteins were enriched at the T2 stage; small heat shock proteins showed significantly higher expression at the T3 stage; and some metabolism-related genes were more highly expressed at the T4 stage. The DEGs identified in this study may serve as a valuable resource for the characterization of expression patterns of antennal genes in A. cerana cerana. Furthermore, this study provides insights into the relationship between labor division in social bees and gene function. Copyright © 2017. Published by Elsevier B.V.

  8. A peroxidase gene expressed during early developmental stages of the parasitic plant Orobanche ramosa.

    Science.gov (United States)

    González-Verdejo, Clara Isabel; Barandiaran, Xabier; Moreno, Maria Teresa; Cubero, José Ignacio; Di Pietro, Antonio

    2006-01-01

    Broomrapes (Orobanche spp.) are holoparasitic weeds that cause devastating losses in many economically important crops. The molecular mechanisms that control the early stages of host infection in Orobanche are poorly understood. In the present study, the role of peroxidase has been examined during pre-infection growth and development of O. ramosa, using an in vitro model system. Peroxidase activity was histochemically localized at the tips of actively growing radicles and nascent attachment organs. Addition of exogenous catalase resulted in a significant reduction in the apical growth rate of the radicle. The prx1 gene encoding a putative class III peroxidase was cloned from a cDNA library of O. ramosa and was found to be expressed specifically during the early stages of the parasitic life cycle. The exogenous addition of sucrose resulted in significantly reduced prx1 transcript levels and in a dramatic change in radicle development from polarized apical growth to isotropic growth and the formation of tubercle-like structures. The results indicate an important role of peroxidases during the early parasitic stages of Orobanche.

  9. Isothiocyanates, Nitriles, and Epithionitriles from Glucosinolates Are Affected by Genotype and Developmental Stage in Brassica oleracea Varieties.

    Science.gov (United States)

    Hanschen, Franziska S; Schreiner, Monika

    2017-01-01

    Vegetables of the Brassica oleracea group, such as broccoli, cauliflower, and cabbage, play an important role for glucosinolate consumption in the human diet. Upon maceration of the vegetable tissue, glucosinolates are degraded enzymatically to form volatile isothiocyanates, nitriles, and epithionitriles. However, only the uptake of isothiocyanates is linked to the cancer-preventive effects. Thus, it is of great interest to evaluate especially the isothiocyanate formation. Here, we studied the formation of glucosinolates and their respective hydrolysis products in sprouts and fully developed vegetable heads of different genotypes of the five B. oleracea varieties: broccoli, cauliflower as well as white, red, and savoy cabbages. Further, the effect of ontogeny (developmental stages) during the head development on the formation of glucosinolates and their respective hydrolysis products was evaluated at three different developmental stages (mini, fully developed, and over-mature head). Broccoli and red cabbage were mainly rich in 4-(methylsulfinyl)butyl glucosinolate (glucoraphanin), whereas cauliflower, savoy cabbage and white cabbage contained mainly 2-propenyl (sinigrin) and 3-(methylsulfinyl)propyl glucosinolate (glucoiberin). Upon hydrolysis, epithionitriles or nitriles were often observed to be the main hydrolysis products, with 1-cyano-2,3-epithiopropane being most abundant with up to 5.7 μmol/g fresh weight in white cabbage sprouts. Notably, sprouts often contained more than 10 times more glucosinolates or their hydrolysis products compared to fully developed vegetables. Moreover, during head development, both glucosinolate concentrations as well as hydrolysis product concentrations changed and mini heads contained the highest isothiocyanate concentrations. Thus, from a cancer-preventive point of view, consumption of mini heads of the B. oleracea varieties is recommended.

  10. Expression and subcellular localization of kinetoplast-associated proteins in the different developmental stages of Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Cavalcanti Danielle

    2009-06-01

    Full Text Available Abstract Background The kinetoplast DNA (kDNA of trypanosomatids consists of an unusual arrangement of circular molecules catenated into a single network. The diameter of the isolated kDNA network is similar to that of the entire cell. However, within the kinetoplast matrix, the kDNA is highly condensed. Studies in Crithidia fasciculata showed that kinetoplast-associated proteins (KAPs are capable of condensing the kDNA network. However, little is known about the KAPs of Trypanosoma cruzi, a parasitic protozoon that shows distinct patterns of kDNA condensation during their complex morphogenetic development. In epimastigotes and amastigotes (replicating forms the kDNA fibers are tightly packed into a disk-shaped kinetoplast, whereas trypomastigotes (non-replicating present a more relaxed kDNA organization contained within a rounded structure. It is still unclear how the compact kinetoplast disk of epimastigotes is converted into a globular structure in the infective trypomastigotes. Results In this work, we have analyzed KAP coding genes in trypanosomatid genomes and cloned and expressed two kinetoplast-associated proteins in T. cruzi: TcKAP4 and TcKAP6. Such small basic proteins are expressed in all developmental stages of the parasite, although present a differential distribution within the kinetoplasts of epimastigote, amastigote and trypomastigote forms. Conclusion Several features of TcKAPs, such as their small size, basic nature and similarity with KAPs of C. fasciculata, are consistent with a role in DNA charge neutralization and condensation. Additionally, the differential distribution of KAPs in the kinetoplasts of distinct developmental stages of the parasite, indicate that the kDNA rearrangement that takes place during the T. cruzi differentiation process is accompanied by TcKAPs redistribution.

  11. Meiotic maturation and developmental capability of ovine oocytes at germinal vesicle stage following vitrification using different cryodevices.

    Science.gov (United States)

    Quan, Guo Bo; Wu, Guo Quan; Wang, Ya Jing; Ma, Yuan; Lv, Chun Rong; Hong, Qiong Hua

    2016-02-01

    In order to assess effects of vitrification on ovine oocytes at the germinal vesicle (GV) stage, the conventional plastic straw (CS), the open-pulled straw (OPS), and Cryoloop were used to vitrify ovine oocytes. Oocytes were randomly divided into five groups: (1) Control; (2) Oocytes exposed to vitrification and dilution solutions without any cryopreservation (toxicity); (3) Oocytes vitrified using CS (CS); (4) Oocytes vitrified using OPS (OPS), and (5) Oocytes vitrified using Cryoloop (Cryoloop). The viability, cumulus cell expansion, nuclear maturation after in vitro maturation (IVM), and developmental capability of vitrified oocytes following parthenogenetic activation (PA) or in vitro fertilization (IVF) were assessed. The pretreatment in the vitrification and dilution solutions without any freezing or thawing did not adversely influence oocytes. The viability of vitrified oocytes were significantly declined compared to unfrozen oocytes (P straws or Cryoloop was significantly higher than that in the CS group (P plastic straws was significantly less than those of the other freezing groups (P straws. However, the cleavage rate of vitrified oocytes in the CS group was significantly less than that in the OPS or Cryoloop group (P plastic straw developed to the blastocyst stage following IVF. There was no significant difference existing between OPS and Cryoloop with respect to the blastocyst rate. After staining with cFDA and PI, cumulus cells surrounding oocytes were partly damaged by vitrification and thawing while the membrane of vitrified oocyte still remained intact. In conclusion, vitrification can seriously damage ovine immature oocytes and cumulus cells surrounding oocytes, which may subsequently affect their developmental capability. Finally, this study further proves that increasing the freezing and thawing velocity benefits survival of vitrified immature oocytes. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Effect of phyto-synthesized silver nanoparticles on developmental stages of malaria vector, Anopheles stephensi and dengue vector, Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Madanagopal Nalini

    2017-09-01

    Full Text Available Rapidly synthesized phyto-mediated silver nanoparticles (Ag NPs using Artemisia nilagirica aqueous leaf filtrate has been confirmed through UV–visible spectrophotometer. The synthesized Ag NPs were further characterized using Fourier transform infra-red (FTIR, X-ray diffraction analysis (XRD to determine the present of functional groups and average particle size (6.723 nm with cubic nature, respectively. Spherical shape (≤30 nm of Ag NPs was confirmed by scanning electron microscopy (SEM. Bio-efficacy of these nanoparticles showed larvicidal and pupicidal properties than the aqueous leaf extract treatment alone against developmental stages (I–IV instars and pupa of malaria vector Anopheles stephensi and dengue vector Aedes aegypti at 0.25% concentration level. The LC50 (LCL:UCL at 95% confidence limit values of I–IV instar and pupa of An. stephensi were recorded at 0.343 (0.261:0.405, 0.169 (0.025:0.263, 0.198 (0.105:0.265, 0.141 (0.045:0.205 and 0.050 (0.606:0.224 % respectively and for Ae. aegypti (I–IV instar and pupa 0.460 (0.364:0.537, 0.352 (0.239:0.432, 0.331 (0.833:0.549, 0.217 (0.228:0.378 and 0.161 (0.630:0.356 % were observed, after 24 h exposure. The first report of present investigation revealed that the rapid biological synthesis of silver nanoparticles using A. nilagirica leaf filtrate would be an effective potential alternative green larvicide for the control of mosquitoes at the developmental stages with eco-friendly approach.

  13. The Transcriptome of Leishmania major Developmental Stages in Their Natural Sand Fly Vector.

    Science.gov (United States)

    Inbar, Ehud; Hughitt, V Keith; Dillon, Laura A L; Ghosh, Kashinath; El-Sayed, Najib M; Sacks, David L

    2017-04-04

    The life cycle of the Leishmania parasite in the sand fly vector involves differentiation into several distinctive forms, each thought to represent an adaptation to specific microenvironments in the midgut of the fly. Based on transcriptome sequencing (RNA-Seq) results, we describe the first high-resolution analysis of the transcriptome dynamics of four distinct stages of Leishmania major as they develop in a natural vector, Phlebotomus duboscqi The early transformation from tissue amastigotes to procyclic promastigotes in the blood-fed midgut was accompanied by the greatest number of differentially expressed genes, including the downregulation of amastins, and upregulation of multiple cell surface proteins, sugar and amino acid transporters, and genes related to glucose metabolism and cell cycle progression. The global changes accompanying post-blood meal differentiation of procyclic promastigotes to the nectomonad and metacyclic stages were less extensive, though each displayed a unique signature. The transcriptome of nectomonads, which has not been studied previously, revealed changes consistent with cell cycle arrest and the upregulation of genes associated with starvation and stress, including autophagic pathways of protein recycling. Maturation to the infective, metacyclic stage was accompanied by changes suggesting preadaptation to the intracellular environment of the mammalian host, demonstrated by the amastigote-like profiles of surface proteins and metabolism-related genes. Finally, a direct comparison between sand fly-derived and culture-derived metacyclics revealed a reassuring similarity between the two forms, with the in vivo forms distinguished mainly by a stronger upregulation of transcripts associated with nutrient stress. IMPORTANCE The life cycle of Leishmania parasites in the sand fly vector includes their growth and development as morphologically distinct forms of extracellular promastigotes found within the different microenvironments of the

  14. The trochlear pre-ossification center: a normal developmental stage and potential pitfall on MR images

    Energy Technology Data Exchange (ETDEWEB)

    Jaimes, Camilo [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Jimenez, Mauricio [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Marin, Diana [Miami Children' s Hospital, Department of Radiology, Miami, FL (United States); Ho-Fung, Victor; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA (United States)

    2012-11-15

    The hypertrophic changes that occur in the cartilage of an epiphysis prior to the onset of ossification are known as the pre-ossification center. Awareness of the appearance of the pre-ossification center on MR images is important to avoid confusing normal developmental changes with pathology. The purpose of this study was to determine the characteristics of the trochlear pre-ossification center on MR imaging and examine age and gender differences. We retrospectively analyzed MR images from 61 children. The trochleas were categorized into three types on the basis of signal intensity (SI). Trochlear types were compared to age and gender. There was no significant difference between the ages of boys and girls. Type 1 trochleas showed homogeneous SI on all pulse sequences. Type 2 trochleas demonstrated a focus of high SI in the epiphyseal cartilage on fat-suppressed water-sensitive sequences, with high or intermediate SI on gradient-echo images (pre-ossification center). Type 3 trochleas showed low SI on fat-suppressed water-sensitive sequences and gradient-echo images. Thirty-seven trochleas were described as type 1, sixteen as type 2 and eight as type 3. ANOVAs confirmed a statistically significant difference in the age of children with type 3 trochleas and those with types 1 and 2 (P < 0.001). Spearman rank correlations determined a positive relationship between trochlear type and age of the children (r = 0.53). Development-related changes in the trochlea follow a predictable pattern. The signal characteristics of the pre-ossification center likely reflect normal chondrocyte hypertrophy and an increase in free water in the matrix. (orig.)

  15. Modeling metabolism and stage-specific growth of Plasmodium falciparum HB3 during the intraerythrocytic developmental cycle.

    Science.gov (United States)

    Fang, Xin; Reifman, Jaques; Wallqvist, Anders

    2014-10-01

    The human malaria parasite Plasmodium falciparum goes through a complex life cycle, including a roughly 48-hour-long intraerythrocytic developmental cycle (IDC) in human red blood cells. A better understanding of the metabolic processes required during the asexual blood-stage reproduction will enhance our basic knowledge of P. falciparum and help identify critical metabolic reactions and pathways associated with blood-stage malaria. We developed a metabolic network model that mechanistically links time-dependent gene expression, metabolism, and stage-specific growth, allowing us to predict the metabolic fluxes, the biomass production rates, and the timing of production of the different biomass components during the IDC. We predicted time- and stage-specific production of precursors and macromolecules for P. falciparum (strain HB3), allowing us to link specific metabolites to specific physiological functions. For example, we hypothesized that coenzyme A might be involved in late-IDC DNA replication and cell division. Moreover, the predicted ATP metabolism indicated that energy was mainly produced from glycolysis and utilized for non-metabolic processes. Finally, we used the model to classify the entire tricarboxylic acid cycle into segments, each with a distinct function, such as superoxide detoxification, glutamate/glutamine processing, and metabolism of fumarate as a byproduct of purine biosynthesis. By capturing the normal metabolic and growth progression in P. falciparum during the IDC, our model provides a starting point for further elucidation of strain-specific metabolic activity, host-parasite interactions, stress-induced metabolic responses, and metabolic responses to antimalarial drugs and drug candidates.

  16. Immature murine NKT cells pass through a stage of developmentally programmed innate IL-4 secretion

    Science.gov (United States)

    Dickgreber, Nina; Farrand, Kathryn J.; van Panhuys, Nicholas; Knight, Deborah A.; McKee, Sara J.; Chong, Mei L.; Miranda-Hernandez, Socorro; Baxter, Alan G.; Locksley, Richard M.; Le Gros, Graham; Hermans, Ian F.

    2012-01-01

    We assessed the production of the canonical Th2 cytokine IL-4 by NKT cells directly in vivo using IL-4-substituting strains of reporter mice that provide faithful and sensitive readouts of cytokine production without the confounding effects of in vitro stimulation. Analysis in naïve animals revealed an “innate” phase of IL-4 secretion that did not need to be triggered by administration of a known NKT cell ligand. This secretion was by immature NKT cells spanning Stage 1 of the maturation process in the thymus (CD4+ CD44lo NK1.1− cells) and Stage 2 (CD4+ CD44hi NK1.1− cells) in the spleen. Like ligand-induced IL-4 production by mature cells, this innate activity was independent of an initial source of IL-4 protein and did not require STAT6 signaling. A more sustained level of innate IL-4 production was observed in animals on a BALB/c background compared with a C57BL/6 background, suggesting a level of genetic regulation that may contribute to the “Th2-prone” phenotype in BALB/c animals. These observations indicate a regulated pattern of IL-4 expression by maturing NKT cells, which may endow these cells with a capacity to influence the development of surrounding cells in the thymus. PMID:22941735

  17. Radiation induction of developmental effects during the very early stages of pregnancy

    International Nuclear Information System (INIS)

    Jacquet, P.

    2009-01-01

    Various studies have shown that early embryos of several mouse strains are sensitive to radiation-induction of congenital anomalies. The presence of mutations in particular genes seems to increase the sensitivity of embryos to such effects, but studies in that field are extremely limited. The aim of these studies is to determine (1) whether the sensitivity to radiation-induction of congenital anomalies during very early stages of gestation is transmitted to the following generation; (2) how mutations in genes involved in important cellular processes, like DNA repair, cell cycle regulation and apoptosis (cell suicide of a damaged cell), can influence the radiation sensitivity of the mammalian embryo during sensitive stages of early pregnancy. Emphasis is put on heterozygous mutations (in which only one of the two copies of the gene is mutated), which are relatively numerous in the human population and do not affect the viability and the fertility of individuals carrying them. The studies under way in that field are supported by contracts with the European Union and the Federal Agency for Nuclear Control (FANC-AFCN)

  18. Developmental steps of the human cervical spine: parameters for evaluation of skeletal maturation stages.

    Science.gov (United States)

    dos Santos, Marcos Fabio Henriques; de Lima, Rodrigo Lopes; De-Ary-Pires, Bernardo; Pires-Neto, Mário Ary; de Ary-Pires, Ricardo

    2010-06-01

    The central objective of this investigation was to focus on the development of the cervical spine observed by lateral cephalometric radiological images of children and adolescents (6-16 years old). A sample of 26 individuals (12 girls and 14 boys) was classified according to stages of cervical spine maturation in two subcategories: group I (initiation phase) and group II (acceleration phase). The morphology of the cervical spine was assessed by lateral cephalometric radiographs obtained in accordance with an innovative method for establishing a standardized head posture. A total of 29 linear variables and 5 angular variables were used to clarify the dimensions of the cervical vertebrae. The results suggest that a few measurements can be used as parameters of vertebral maturation both for males and females. The aforementioned measurements include the inferior depth of C2-C4, the inferior depth of C5, the anterior height of C4-C5, and the posterior height of C5. We propose original morphological parameters that may prove remarkably useful in the determination of bone maturational stages of the cervical spine in children and adolescents.

  19. Diversity of immunoglobulin lambda light chain gene usage over developmental stages in the horse.

    Science.gov (United States)

    Tallmadge, Rebecca L; Tseng, Chia T; Felippe, M Julia B

    2014-10-01

    To further studies of neonatal immune responses to pathogens and vaccination, we investigated the dynamics of B lymphocyte development and immunoglobulin (Ig) gene diversity. Previously we demonstrated that equine fetal Ig VDJ sequences exhibit combinatorial and junctional diversity levels comparable to those of adult Ig VDJ sequences. Herein, RACE clones from fetal, neonatal, foal, and adult lymphoid tissue were assessed for Ig lambda light chain combinatorial, junctional, and sequence diversity. Remarkably, more lambda variable genes (IGLV) were used during fetal life than later stages and IGLV gene usage differed significantly with time, in contrast to the Ig heavy chain. Junctional diversity measured by CDR3L length was constant over time. Comparison of Ig lambda transcripts to germline revealed significant increases in nucleotide diversity over time, even during fetal life. These results suggest that the Ig lambda light chain provides an additional dimension of diversity to the equine Ig repertoire. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Prediction of in-vitro developmental competence of early cleavage-stage mouse embryos with compact time-lapse equipment.

    Science.gov (United States)

    Pribenszky, Csaba; Losonczi, Eszter; Molnár, Miklós; Lang, Zsolt; Mátyás, Szabolcs; Rajczy, Klára; Molnár, Katalin; Kovács, Péter; Nagy, Péter; Conceicao, Jason; Vajta, Gábor

    2010-03-01

    Single blastocyst transfer is regarded as an efficient way to achieve high pregnancy rates and to avoid multiple pregnancies. Risk of cancellation of transfer due to a lack of available embryos may be reduced by early prediction of blastocyst development. Time-lapse investigation of mouse embryos shows that the time of the first and second cleavage (to the 2- and 3-cell stages, respectively) has a strong predictive value for further development in vitro, while cleavage from the 3-cell to the 4-cell stage has no predictive value. In humans, embryo fragmentation during preimplantation development has been associated with lower pregnancy rates and a higher incidence of developmental abnormalities. Analysis of time-lapse records shows that most fragmentation is reversible in the mouse and is resorbed in an average of 9 h. Daily or bi-daily microscopic checks of embryo development, applied routinely in human IVF laboratories, would fail to detect 36 or 72% of these fragmentations, respectively. Fragmentation occurring in a defined time frame has a strong predictive value for in-vitro embryo development. The practical compact system used in the present trial, based on the 'one camera per patient' principle, has eliminated the usual disadvantages of time-lapse investigations and is applicable for the routine follow-up of in-vitro embryo development. Copyright 2009 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  1. Predator mediated selection and the impact of developmental stage on viability in wood frog tadpoles (Rana sylvatica

    Directory of Open Access Journals (Sweden)

    Calsbeek Ryan

    2011-12-01

    Full Text Available Abstract Background Complex life histories require adaptation of a single organism for multiple ecological niches. Transitions between life stages, however, may expose individuals to an increased risk of mortality, as the process of metamorphosis typically includes developmental stages that function relatively poorly in both the pre- and post-metamorphic habitat. We studied predator-mediated selection on tadpoles of the wood frog, Rana sylvatica, to identify this hypothesized period of differential predation risk and estimate its ontogenetic onset. We reared tadpoles in replicated mesocosms in the presence of the larval odonate Anax junius, a known tadpole predator. Results The probability of tadpole survival increased with increasing age and size, but declined steeply at the point in development where hind limbs began to erupt from the body wall. Selection gradient analyses indicate that natural selection favored tadpoles with short, deep tail fins. Tadpoles resorb their tails as they progress toward metamorphosis, which may have led to the observed decrease in survivorship. Path models revealed that selection acted directly on tail morphology, rather than through its indirect influence on swimming performance. Conclusions This is consistent with the hypothesis that tail morphology influences predation rates by reducing the probability a predator strikes the head or body.

  2. Histological and allometric growth analysis of eye in Caspian kutum, Rutilus kutum Kamensky, 1901 (Teleostei: Cyprinidae during early developmental stages

    Directory of Open Access Journals (Sweden)

    Shaghayegh Hasanpour

    2016-10-01

    Full Text Available Fish larvae have several sensory systems that are functional at or soon after hatching and then are developed further during larval and juvenile stages. This study was conducted to investigate development of the eye in Rutilus kutum, based on histological and allometric growth analysis during early developmental stages up to 35 day post hatching with emphasis on retinal morphology. For this purpose, the histological sections were prepared and allometric growth pattern of the eye was calculated. The results showed that the most eye’s structures along with the retina of the newly hatched larvae, as the inner sensory (photosensitive tissue were completely differentiated. Allometric growth pattern of the eye diameter up to the inflexion point (7 dph was somewhat positive and then it became negative. The results revealed that the Caspian kutum is dependence on visual capability as visual feeder during their larval period which itself explains completion of eye structures and the high growth rate of eye before 3 dph i.e. beginning of mixed feeding.

  3. Is early adulthood a critical developmental stage for psychosis proneness? A survey of delusional ideation in normal subjects.

    Science.gov (United States)

    Verdoux, H; van Os, J; Maurice-Tison, S; Gay, B; Salamon, R; Bourgeois, M

    1998-02-09

    It has been hypothesized that late adolescence and early adulthood might be a brain developmental stage favoring the clinical expression of psychotic symptoms in psychiatric or neurological diseases. The aim of the present survey was to examine the relationship between age and delusional ideation in a sample of subjects with no psychiatric disorder. The survey was carried out with the Aquitaine Sentinel Network of general practitioners. Consecutive practice attenders were invited to complete the PDI-21 (Peters Delusional Inventory 21 items), a self-report questionnaire designed to measure delusional ideation in the normal population. The study concerned 444 patients who had no lifetime history of psychiatric disorder and who completed the PDI-21. A principal component analysis of the PDI-21 items was performed in order to identify delusional dimensions. An age-related decrease in the likelihood to report delusional ideas was found, younger subjects scoring higher on most dimensions of delusional ideation, such as 'persecution', 'thought disturbance', 'grandiosity' and 'paranormal beliefs'. 'Religiosity' was the only dimension positively associated with age. The results suggest that there may be a physiological neurodevelopmental stage favouring the expression of psychosis proneness in normal subjects, and support the hypothesis that the association between age and positive psychotic symptoms in functional and organic psychoses may be linked to the interaction between normal brain maturational processes and cerebral abnormalities involved in the aetiology of functional and organic psychoses.

  4. Analysis of 1202 orthopantograms to evaluate the potential of forensic age determination based on third molar developmental stages.

    Science.gov (United States)

    Willershausen, B; Löffler, N; Schulze, R

    2001-09-28

    A total of 1202 orthopantograms of young dental patients were analyzed to assess the correlation of third molar root development with chronological age. The investigated patients were treated at a university dental clinic on an outpatient basis, included a variety of demographic characteristics (600 males and 602 females, 28% of other than central European background), and were 15-24 years old when the radiographs were obtained. Radiographs in which more than one third molar were either missing due to agenesia or extraction, or not evaluable because of deep destruction or marked tilting, were not included in the analysis. Our findings show that the growth patterns of third molars, based on seven defined stages of root development, did correlate with chronological age; age estimation when applied to a specific individual would involve a margin of error of +/- 2-4 years. There were no significant differences between the left and right jaw segments, but the stage of root development was generally more advanced in the upper than in the lower third molars. Root development was also more advanced among boys than among girls of the same age. There were no apparent differences in growth patterns based on national/ethnic background. While only 2.5% of 18-year-olds revealed fully developed third molars in all four quadrants, this percentage leaped to 38.4% among the 21-year-olds. To summarize, while the developmental stage of third molars is not per se a highly useful indicator of chronological age in juveniles and young adults, it is nevertheless a valuable supplementary parameter given the scarcity of other available age indicators.

  5. Tumor Necrosis Factor Induces Developmental Stage-Dependent Structural Changes in the Immature Small Intestine

    Directory of Open Access Journals (Sweden)

    Kathryn S. Brown

    2014-01-01

    Full Text Available Background. Premature infants are commonly subject to intestinal inflammation. Since the human small intestine does not reach maturity until term gestation, premature infants have a unique challenge, as either acute or chronic inflammation may alter the normal development of the intestinal tract. Tumor necrosis factor (TNF has been shown to acutely alter goblet cell numbers and villus length in adult mice. In this study we tested the effects of TNF on villus architecture and epithelial cells at different stages of development of the immature small intestine. Methods. To examine the effects of TNF-induced inflammation, we injected acute, brief, or chronic exposures of TNF in neonatal and juvenile mice. Results. TNF induced significant villus blunting through a TNF receptor-1 (TNFR1 mediated mechanism, leading to loss of villus area. This response to TNFR1 signaling was altered during intestinal development, despite constant TNFR1 protein expression. Acute TNF-mediated signaling also significantly decreased Paneth cells. Conclusions. Taken together, the morphologic changes caused by TNF provide insight as to the effects of inflammation on the developing intestinal tract. Additionally, they suggest a mechanism which, coupled with an immature immune system, may help to explain the unique susceptibility of the immature intestine to inflammatory diseases such as NEC.

  6. Assessment of heavy metals in Averrhoa bilimbi and A. carambola fruit samples at two developmental stages.

    Science.gov (United States)

    Soumya, S L; Nair, Bindu R

    2016-05-01

    Though the fruits of Averrhoa bilimbi and A. carambola are economically and medicinally important, they remain underutilized. The present study reports heavy metal quantitation in the fruit samples of A. bilimbi and A. carambola (Oxalidaceae), collected at two stages of maturity. Heavy metals are known to interfere with the functioning of vital cellular components. Although toxic, some elements are considered essential for human health, in trace quantities. Heavy metals such as Cr, Mn, Co, Cu, Zn, As, Se, Pb, and Cd were analyzed by atomic absorption spectroscopy (AAS). The samples under investigation included, A. bilimbi unripe (BU) and ripe (BR), A. carambola sour unripe (CSU) and ripe (CSR), and A. carambola sweet unripe (CTU) and ripe (CTR). Heavy metal analysis showed that relatively higher level of heavy metals was present in BR samples compared to the rest of the samples. The highest amount of As and Se were recorded in BU samples while Mn content was highest in CSU samples and Co in CSR. Least amounts of Cr, Zn, Se, Cd, and Pb were noted in CTU while, Mn, Cu, and As were least in CTR. Thus, the sweet types of A. carambola (CTU, CTR) had comparatively lower heavy metal content. There appears to be no reason for concern since different fruit samples of Averrhoa studied presently showed the presence of various heavy metals in trace quantities.

  7. Thermotolerance and Heat-Shock Protein Gene Expression Patterns in Bemisia tabaci (Hemiptera: Aleyrodidae) Mediterranean in Relation to Developmental Stage.

    Science.gov (United States)

    Jiang, Rui; Qi, Lan-Da; Du, Yu-Zhou; Li, Yuan-Xi

    2017-10-01

    Temperature plays an important role in the growth, development, and geographic distribution of insects. There is convincing evidence that heat-shock proteins (HSPs) play important roles in helping organisms adapt to thermal stress. To better understand the physiological and ecological influence of thermal stress on the different development stages of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Mediterranean species (MED), nymphs and adults were shocked with temperatures of 35, 38, and 41℃ for 1 and 2 h, respectively, and the survival rate, fecundity, and developmental duration were investigated in the laboratory. The expression levels of the hsp40, hsp70, and hsp90 genes were assessed using real-time PCR. The results indicate that the survival rates of the nymphs and adults decreased with increased temperature. A 2-h heat shock at 41℃ induced a significant reduction in fecundity in adults and an increase in developmental duration in young nymphs. Hsp90 showed higher temperature responses to thermal stress than hsp40 or hsp70. The expression levels of the hsps in the adults were significantly down-regulated by a 2-h heat shock at 41℃ compared with that by a 1-h treatment. A significant decrease in the expression levels of the hsps also occurred in the adults when the temperature increased from 38 to 41℃ for the 2-h treatment, whereas no significant decrease occurred in the nymphs. Compared with previous studies, we provide some evidence indicating that MED has the potential to adapt to a wider temperature range than the Middle East-Asia Minor 1 species. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. A new ontology (structured hierarchy) of human developmental anatomy for the first 7 weeks (Carnegie stages 1-20).

    Science.gov (United States)

    Bard, Jonathan

    2012-11-01

    This paper describes a new ontology of human developmental anatomy covering the first 49 days [Carnegie stages (CS)1-20], primarily structured around the parts of organ systems and their development. The ontology includes more than 2000 anatomical entities (AEs) that range from the whole embryo, through organ systems and organ parts down to simple or leaf tissues (groups of cells with the same morphological phenotype), as well as features such as cavities. Each AE has assigned to it a set of facts of the form , with the relationships including starts_at and ends_at (CSs), part_of (there can be several parents) and is_a (this gives the type of tissue, from an organ system down to one of ~ 80 simple tissues predominantly composed of a single cell kind, which is also specified). Leaf tissues also have a develops_from link to its parent tissue. The ontology includes ~14 000 such facts, which are mainly from the literature and an earlier ontology of human developmental anatomy (EHDAA, now withdrawn). The relationships enable these facts to be integrated into a single, complex hierarchy (or mathematical graph) that was made and can be viewed in the OBO-Edit browser (oboedit.org). Each AE has an EHDAA2 ID that may be useful in an informatics context, while the ontology as a whole can be used for organizing databases of human development. It is also a knowledge resource: a user can trace the lineage of any tissue back to the egg, study the changes in cell phenotype that occur as a tissue develops, and use the structure to add further (e.g. molecular) information. The ontology may be downloaded from www.obofoundry.org. Queries and corrections should be sent to j.bard@ed.ac.uk. © 2012 The Author Journal of Anatomy © 2012 Anatomical Society.

  9. Semiautomated analysis of embryoscope images: Using localized variance of image intensity to detect embryo developmental stages.

    Science.gov (United States)

    Mölder, Anna; Drury, Sarah; Costen, Nicholas; Hartshorne, Geraldine M; Czanner, Silvester

    2015-02-01

    Embryo selection in in vitro fertilization (IVF) treatment has traditionally been done manually using microscopy at intermittent time points during embryo development. Novel technique has made it possible to monitor embryos using time lapse for long periods of time and together with the reduced cost of data storage, this has opened the door to long-term time-lapse monitoring, and large amounts of image material is now routinely gathered. However, the analysis is still to a large extent performed manually, and images are mostly used as qualitative reference. To make full use of the increased amount of microscopic image material, (semi)automated computer-aided tools are needed. An additional benefit of automation is the establishment of standardization tools for embryo selection and transfer, making decisions more transparent and less subjective. Another is the possibility to gather and analyze data in a high-throughput manner, gathering data from multiple clinics and increasing our knowledge of early human embryo development. In this study, the extraction of data to automatically select and track spatio-temporal events and features from sets of embryo images has been achieved using localized variance based on the distribution of image grey scale levels. A retrospective cohort study was performed using time-lapse imaging data derived from 39 human embryos from seven couples, covering the time from fertilization up to 6.3 days. The profile of localized variance has been used to characterize syngamy, mitotic division and stages of cleavage, compaction, and blastocoel formation. Prior to analysis, focal plane and embryo location were automatically detected, limiting precomputational user interaction to a calibration step and usable for automatic detection of region of interest (ROI) regardless of the method of analysis. The results were validated against the opinion of clinical experts. © 2015 International Society for Advancement of Cytometry. © 2015 International

  10. Effects of climatic factors on prevalence of developmental stages of Fasciola gigantica infection in Lymnaea snails (Lymnaea auricularia var rufescens in Bangladesh

    Directory of Open Access Journals (Sweden)

    Islam, K.M

    2015-10-01

    Full Text Available The present study was conducted to investigate the prevalence of developmental stages of Fasciola gigantica infection in Lymnaea snails and their populations in Sylhet region of Bangladesh. A total of 1865 Lymnaea snails were collected and examined, of which 56 (3% were found to having infected with developmental stages of Fasciola gigantica. Only 4.08% infected of 515 snails were collected from Biswanath Upazilla followed by 3.16% of 443 from Beanibazar, 2.53% of 396 from Balaganj then 2.40% of 292 Jaintapur Upazilla and the lowest 1.83% of 219 from Sylhet Sadar. Month-wise data, the prevalence of snail infections was observed to be the highest in May (5.06% and August (5.61% and the lowest in March (0.74% and February (0.68%. However there was no infection observed through November to January. Seasonal prevalence of the developmental stages of F. gigantica infection in Lymnaea snails was also studied. Highest prevalence (4.63% was recorded during rainy season and lowest prevalence (0.76% was recorded during winter season. The study revealed that the developmental stages of F. gigantica infection in snail populations decreases from November to January and increases from February to October and highest in August and September in Sylhet region of Bangladesh.

  11. A developmental stage-specific switch from DAZL to BOLL occurs during fetal oogenesis in humans, but not mice.

    Directory of Open Access Journals (Sweden)

    Jing He

    Full Text Available The Deleted in Azoospermia gene family encodes three germ cell-specific RNA-binding proteins (DAZ, DAZL and BOLL that are essential for gametogenesis in diverse species. Targeted disruption of Boll in mice causes male-specific spermiogenic defects, but females are apparently fertile. Overexpression of human BOLL promotes the derivation of germ cell-like cells from genetically female (XX, but not male (XY human ES cells however, suggesting a functional role for BOLL in regulating female gametogenesis in humans. Whether BOLL is expressed during oogenesis in mammals also remains unclear. We have therefore investigated the expression of BOLL during fetal oogenesis in humans and mice. We demonstrate that BOLL protein is expressed in the germ cells of the human fetal ovary, at a later developmental stage than, and almost mutually-exclusive to, the expression of DAZL. Strikingly, BOLL is downregulated, and DAZL re-expressed, as primordial follicles form, revealing BOLL expression to be restricted to a narrow window during fetal oogenesis. By quantifying the extent of co-expression of DAZL and BOLL with markers of meiosis, we show that this window likely corresponds to the later stages of meiotic prophase I. Finally, we demonstrate that Boll is also transiently expressed during oogenesis in the fetal mouse ovary, but is simultaneously co-expressed within the same germ cells as Dazl. These data reveal significant similarities and differences between the expression of BOLL homologues during oogenesis in humans and mice, and raise questions as to the validity of the Boll(-/- mouse as a model for understanding BOLL function during human oogenesis.

  12. Developmental stage-dependent influence of environmental factors on growth of rural Sundanese children in West Java, Indonesia.

    Science.gov (United States)

    Sekiyama, Makiko; Roosita, Katrin; Ohtsuka, Ryutaro

    2015-05-01

    This study investigated the growth trajectories and the relative relevance levels of nutrition, disease, and hormonal status at various developmental stages among children in adverse environments to provide population-based empirical evidence for the life history theory. Three years of longitudinal anthropometric data in 1-year intervals were obtained from 418 boys and girls aged 0 to 12 years at recruitment. Following the final measurement, the main survey, which included blood and feces sampling, 3-h interval food consumption recall surveys for energy and nutrient intakes and anthropometry, was performed. Blood and feces were used for detecting, respectively, anemia and hormonal (IGF-I and IGFBP-3) levels as well as intestinal helminthiasis (Ascaris, Trichuris, and hookworm). The major findings of this study are summarized as follows: 1) the growth velocity of the subject children lagged behind international standards during childhood and juvenility but caught up during early adolescence; 2) diseases, both intestinal helminths and anemia, had significant effects on growth in childhood but not at older ages; and 3) hormonal status significantly affected growth in the children, with its highest significance in early adolescence. A larger growth than international standards in early adolescence likely follows programmed hormonal mechanisms after the onset of puberty. The onset of puberty might be associated with adequate amounts of nutrient intake and be mediated by hormonal function, because the IGF-IZ score was significantly correlated with energy and protein intakes at the transitional period from juvenility to adolescence, when puberty occurs. © 2015 Wiley Periodicals, Inc.

  13. Expression of PAT and NPT II proteins during the developmental stages of a genetically modified pepper developed in Korea.

    Science.gov (United States)

    Kim, Hyo Jin; Lee, Si Myung; Kim, Jae Kwang; Ryu, Tae Hun; Suh, Seok Cheol; Cho, Hyun Suk

    2010-10-27

    Estimation of the protein levels introduced in a biotechnology-derived product is conducted as part of an overall safety assessment. An enzyme-linked immunosorbent assay (ELISA) was used to analyze phosphinothricin acetyltransferase (PAT) and neomycin phosphotransferase II (NPT II) protein expression in a genetically modified (GM) pepper plant developed in Korea. PAT and NPT II expression levels, based on both dry weight and fresh weight, were variable among different plant generations and plant sections from isolated genetically modified organism (GMO) fields at four developmental stages. PAT expression was highest in leaves at anthesis (11.44 μg/gdw and 2.17 μg/gfw) and lowest in roots (0.12 μg/gdw and 0.01 μg/gfw). NPT II expression was also highest in leaves at anthesis (17.31 μg/gdw and 3.41 μg/gfw) and lowest in red pepper (0.65 μg/gdw and 0.12 μg/gfw). In pollen, PAT expression was 0.59-0.62 μg/gdw, while NPT II was not detected. Both PAT and NPT II showed a general pattern of decreased expression with progression of the growing season. As expected, PAT and NPT II protein expression was not detectable in control pepper plants.

  14. Analysis of temporal transcription expression profiles reveal links between protein function and developmental stages of Drosophila melanogaster.

    Science.gov (United States)

    Wan, Cen; Lees, Jonathan G; Minneci, Federico; Orengo, Christine A; Jones, David T

    2017-10-01

    Accurate gene or protein function prediction is a key challenge in the post-genome era. Most current methods perform well on molecular function prediction, but struggle to provide useful annotations relating to biological process functions due to the limited power of sequence-based features in that functional domain. In this work, we systematically evaluate the predictive power of temporal transcription expression profiles for protein function prediction in Drosophila melanogaster. Our results show significantly better performance on predicting protein function when transcription expression profile-based features are integrated with sequence-derived features, compared with the sequence-derived features alone. We also observe that the combination of expression-based and sequence-based features leads to further improvement of accuracy on predicting all three domains of gene function. Based on the optimal feature combinations, we then propose a novel multi-classifier-based function prediction method for Drosophila melanogaster proteins, FFPred-fly+. Interpreting our machine learning models also allows us to identify some of the underlying links between biological processes and developmental stages of Drosophila melanogaster.

  15. Analysis of temporal transcription expression profiles reveal links between protein function and developmental stages of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Cen Wan

    2017-10-01

    Full Text Available Accurate gene or protein function prediction is a key challenge in the post-genome era. Most current methods perform well on molecular function prediction, but struggle to provide useful annotations relating to biological process functions due to the limited power of sequence-based features in that functional domain. In this work, we systematically evaluate the predictive power of temporal transcription expression profiles for protein function prediction in Drosophila melanogaster. Our results show significantly better performance on predicting protein function when transcription expression profile-based features are integrated with sequence-derived features, compared with the sequence-derived features alone. We also observe that the combination of expression-based and sequence-based features leads to further improvement of accuracy on predicting all three domains of gene function. Based on the optimal feature combinations, we then propose a novel multi-classifier-based function prediction method for Drosophila melanogaster proteins, FFPred-fly+. Interpreting our machine learning models also allows us to identify some of the underlying links between biological processes and developmental stages of Drosophila melanogaster.

  16. Effect of SKT-b Vibrio probiotic bacteria addition at different developmental stages on tiger shrimp Penaeus monodon larvae survival rate

    Directory of Open Access Journals (Sweden)

    . Widanarni

    2009-07-01

    Full Text Available This experiment was conducted to study the effect of probiotic bacteria SKT-b Vibrio addition at different developmental stages on survival rates of tiger shrimp Penaeus monodon larva.  Main activity of this experiment consisted of tiger shrimp rearing started from nauplius stage until Pl10 and addition of 106 CFU/ml SKT-b Vibrio probiotic bacteria at various developmental stages namely at early nauplius stage, early zoea zoea stage, early mysis stage, early postlarva (Pl stage, every developmental stage changes, everyday, and control (without probiotic bacteria addition. Results showed that survival rates of shrimp larva ranged at 24,17%-35,83% with the higest value in the treatment of probiotic bacteria addition at every developmental stage changes namely 35,83%, whereas the lowest was found at control (without probiotic bacteria addition namely 24,17%.  No significantly different was found in term of shrimp growth rate among control and treatment. Growth rate in length of tiger shrimp larva ranged 18,64%-19,09% for SKT-b Vibrio addition and 18,47% for control. Key word: Probiotic bacteria, SKT-b Vibrio, Penaeus monodon, shrimp larvae stages   ABSTRAK Penelitian ini dilakukan untuk mempelajari pengaruh pemberian bakteri probiotik Vibrio SKT-b pada stadia yang berbeda terhadap kelangsungan hidup larva udang windu Penaeus monodon. Kegiatan utama dari penelitian ini adalah pemeliharaan udang windu yang dimulai dari stadia nauplius sampai Pl10 dan diberi bakteri probiotik Vibrio SKT-b dengan dosis 106 CFU/ml pada waktu yang berbeda yaitu pada awal stadia nauplius, awal stadia zoea, awal stadia mysis, awal stadia postlarva (Pl, setiap pergantian stadia, setiap hari, dan kontrol (tanpa pemberian bakteri probiotik. Hasil penelitian yang diperoleh menunjukkan bahwa tingkat kelangsungan hidup larva udang berkisar antara 24,17%-35,83% dengan nilai tertinggi terdapat pada perlakuan pemberian bakteri probiotik pada setiap pergantian stadia yaitu

  17. Human developmental anatomy: microscopic magnetic resonance imaging (μMRI) of four human embryos (from Carnegie Stage 10 to 20).

    Science.gov (United States)

    Lhuaire, Martin; Martinez, Agathe; Kaplan, Hervé; Nuzillard, Jean-Marc; Renard, Yohann; Tonnelet, Romain; Braun, Marc; Avisse, Claude; Labrousse, Marc

    2014-12-01

    Technological advances in the field of biological imaging now allow multi-modal studies of human embryo anatomy. The aim of this study was to assess the high magnetic field μMRI feasibility in the study of small human embryos (less than 21mm crown-rump) as a new tool for the study of human descriptive embryology and to determine better sequence characteristics to obtain higher spatial resolution and higher signal/noise ratio. Morphological study of four human embryos belonging to the historical collection of the Department of Anatomy in the Faculty of Medicine of Reims was undertaken by μMRI. These embryos had, successively, crown-rump lengths of 3mm (Carnegie Stage, CS 10), 12mm (CS 16), 17mm (CS 18) and 21mm (CS 20). Acquisition of images was performed using a vertical nuclear magnetic resonance spectrometer, a Bruker Avance III, 500MHz, 11.7T equipped for imaging. All images were acquired using 2D (transverse, sagittal and coronal) and 3D sequences, either T1-weighted or T2-weighted. Spatial resolution between 24 and 70μm/pixel allowed clear visualization of all anatomical structures of the embryos. The study of human embryos μMRI has already been reported in the literature and a few atlases exist for educational purposes. However, to our knowledge, descriptive or morphological studies of human developmental anatomy based on data collected these few μMRI studies of human embryos are rare. This morphological noninvasive imaging method coupled with other techniques already reported seems to offer new perspectives to descriptive studies of human embryology.

  18. GC-MS Metabolomic Analysis to Reveal the Metabolites and Biological Pathways Involved in the Developmental Stages and Tissue Response of Panax ginseng

    Directory of Open Access Journals (Sweden)

    Jia Liu

    2017-03-01

    Full Text Available Ginsenosides, the major compounds present in ginseng, are known to have numerous physiological and pharmacological effects. The physiological processes, enzymes and genes involved in ginsenoside synthesis in P. ginseng have been well characterized. However, relatively little information is known about the dynamic metabolic changes that occur during ginsenoside accumulation in ginseng. To explore this topic, we isolated metabolites from different tissues at different growth stages, and identified and characterized them by using gas chromatography coupled with mass spectrometry (GC-MS. The results showed that a total of 30, 16, 20, 36 and 31 metabolites were identified and involved in different developmental stages in leaf, stem, petiole, lateral root and main root, respectively. To investigate the contribution of tissue to the biosynthesis of ginsenosides, we examined the metabolic changes of leaf, stem, petiole, lateral root and main root during five development stages: 1-, 2-, 3-, 4- and 5-years. The score plots of partial least squares-discriminate analysis (PLS-DA showed clear discrimination between growth stages and tissue samples. Kyoto Encyclopedia of Genes and Genomes (KEGG pathway analysis in the same tissue at different growth stages indicated profound biochemical changes in several pathways, including carbohydrate metabolism and pentose phosphate metabolism, in addition, the tissues displayed significant variations in amino acid metabolism, sugar metabolism and energy metabolism. These results should facilitate further dissection of the metabolic flux regulation of ginsenoside accumulation in different developmental stages or different tissues of ginseng.

  19. Developmental Competence of Vitrified-Warmed Bovine Oocytes at the Germinal-Vesicle Stage is Improved by Cyclic Adenosine Monophosphate Modulators during In Vitro Maturation.

    Directory of Open Access Journals (Sweden)

    Kenji Ezoe

    Full Text Available Cryopreservation of mature oocytes and embryos has provided numerous benefits in reproductive medicine. Although successful cryopreservation of germinal-vesicle stage (GV oocytes holds promise for further advances in reproductive biology and clinical embryology fields, reports regarding cryopreservation of immature oocytes are limited. Oocyte survival and maturation rates have improved since vitrification is being performed at the GV stage, but the subsequent developmental competence of GV oocytes is still low. The purpose of this study was to evaluate the effects of supplementation of the maturation medium with cyclic adenosine monophosphate (cAMP modulators on the developmental competence of vitrified-warmed GV bovine oocytes. GV oocytes were vitrified-warmed and cultured to allow for oocyte maturation, and then parthenogenetically activated or fertilized in vitro. Our results indicate that addition of a cAMP modulator forskolin (FSK or 3-isobutyl-1-methylxanthine (IBMX to the maturation medium significantly improved the developmental competence of vitrified-warmed GV oocytes. We also demonstrated that vitrification of GV oocytes led to a decline in cAMP levels and maturation-promoting factor (MPF activity in the oocytes during the initial and final phases of maturation, respectively. Nevertheless, the addition of FSK or IBMX to the maturation medium significantly elevated cAMP levels and MPF activity during IVM. Taken together, our results suggest that the cryopreservation-associated meiotic and developmental abnormalities observed in GV oocytes may be ameliorated by an artificial increase in cAMP levels during maturation culture after warming.

  20. Identification and validation of reference genes for qRT-PCR studies of the obligate aphid pathogenic fungus Pandora neoaphidis during different developmental stages

    OpenAIRE

    Zhang, Shutao; Chen, Chun; Xie, Tingna; Ye, Sudan

    2017-01-01

    The selection of stable reference genes is a critical step for the accurate quantification of gene expression. To identify and validate the reference genes in Pandora neoaphidis-an obligate aphid pathogenic fungus-the expression of 13classical candidate reference genes were evaluated by quantitative real-time reverse transcriptase polymerase chain reaction(qPCR) at four developmental stages (conidia, conidia with germ tubes, short hyphae and elongated hyphae). Four statistical algorithms, inc...

  1. Human dental age estimation using third molar developmental stages: does a Bayesian approach outperform regression models to discriminate between juveniles and adults?

    OpenAIRE

    Thevissen, P. W.; FIEUWS, Steffen; Willems, G.

    2010-01-01

    Dental age estimation methods based on the radiologically detected third molar developmental stages are implemented in forensic age assessments to discriminate between juveniles and adults considering the judgment of young unaccompanied asylum seekers. Accurate and unbiased age estimates combined with appropriate quantified uncertainties are the required properties for accurate forensic reporting. In this study, a subset of 910 individuals uniformly distributed in age between 16 and 22 years ...

  2. Human dental age estimation using third molar developmental stages: does a Bayesian approach outperform regression models to discriminate between juveniles and adults?

    Science.gov (United States)

    Thevissen, P W; Fieuws, S; Willems, G

    2010-01-01

    Dental age estimation methods based on the radiologically detected third molar developmental stages are implemented in forensic age assessments to discriminate between juveniles and adults considering the judgment of young unaccompanied asylum seekers. Accurate and unbiased age estimates combined with appropriate quantified uncertainties are the required properties for accurate forensic reporting. In this study, a subset of 910 individuals uniformly distributed in age between 16 and 22 years was selected from an existing dataset collected by Gunst et al. containing 2,513 panoramic radiographs with known third molar developmental stages of Belgian Caucasian men and women. This subset was randomly split in a training set to develop a classical regression analysis and a Bayesian model for the multivariate distribution of the third molar developmental stages conditional on age and in a test set to assess the performance of both models. The aim of this study was to verify if the Bayesian approach differentiates the age of maturity more precisely and removes the bias, which disadvantages the systematically overestimated young individuals. The Bayesian model offers the discrimination of subjects being older than 18 years more appropriate and produces more meaningful prediction intervals but does not strongly outperform the classical approaches.

  3. Atomic resolution structures of discrete stages on the reaction coordinate of the [Fe4S4] enzyme IspG (GcpE)

    KAUST Repository

    Quitterer, Felix; Frank, Annika; Wang, Ke; Rao, Guodong; O'Dowd, Bing; Li, Jikun; Guerra, Francisco; Abdel-Azeim, Safwat; Bacher, Adelbert; Eppinger, Jö rg; Oldfield, Eric; Groll, Michael

    2015-01-01

    IspG is the penultimate enzyme in non-mevalonate biosynthesis of the universal terpene building blocks isopentenyl diphosphate and dimethylallyl diphosphate. Its mechanism of action has been the subject of numerous studies but remained unresolved due to difficulties in identifying distinct reaction intermediates. Using a moderate reducing agent as well as an epoxide substrate analogue, we were now able to trap and crystallographically characterize various stages in the IspG catalyzed conversion of 2-C-methyl-D-erythritol-2,4-cyclo-diphosphate (MEcPP) to (E)-1-hydroxy-2-methylbut-2-enyl-4-diphosphate (HMBPP). In addition, the enzyme’s structure was determined in complex with several inhibitors. These results, combined with recent electron paramagnetic resonance data, allowed us to deduce a detailed and complete IspG catalytic mechanism which describes all stages from initial ring opening to formation of HMBPP via discrete radical and carbanion intermediates. The data presented in this article provide a guide for the design of selective drugs against many pro- and eukaryotic pathogens to which the non-mevalonate pathway is essential for survival and virulence.

  4. Atomic resolution structures of discrete stages on the reaction coordinate of the [Fe4S4] enzyme IspG (GcpE)

    KAUST Repository

    Quitterer, Felix

    2015-04-11

    IspG is the penultimate enzyme in non-mevalonate biosynthesis of the universal terpene building blocks isopentenyl diphosphate and dimethylallyl diphosphate. Its mechanism of action has been the subject of numerous studies but remained unresolved due to difficulties in identifying distinct reaction intermediates. Using a moderate reducing agent as well as an epoxide substrate analogue, we were now able to trap and crystallographically characterize various stages in the IspG catalyzed conversion of 2-C-methyl-D-erythritol-2,4-cyclo-diphosphate (MEcPP) to (E)-1-hydroxy-2-methylbut-2-enyl-4-diphosphate (HMBPP). In addition, the enzyme’s structure was determined in complex with several inhibitors. These results, combined with recent electron paramagnetic resonance data, allowed us to deduce a detailed and complete IspG catalytic mechanism which describes all stages from initial ring opening to formation of HMBPP via discrete radical and carbanion intermediates. The data presented in this article provide a guide for the design of selective drugs against many pro- and eukaryotic pathogens to which the non-mevalonate pathway is essential for survival and virulence.

  5. Automatic sleep staging using empirical mode decomposition, discrete wavelet transform, time-domain, and nonlinear dynamics features of heart rate variability signals.

    Science.gov (United States)

    Ebrahimi, Farideh; Setarehdan, Seyed-Kamaledin; Ayala-Moyeda, Jose; Nazeran, Homer

    2013-10-01

    The conventional method for sleep staging is to analyze polysomnograms (PSGs) recorded in a sleep lab. The electroencephalogram (EEG) is one of the most important signals in PSGs but recording and analysis of this signal presents a number of technical challenges, especially at home. Instead, electrocardiograms (ECGs) are much easier to record and may offer an attractive alternative for home sleep monitoring. The heart rate variability (HRV) signal proves suitable for automatic sleep staging. Thirty PSGs from the Sleep Heart Health Study (SHHS) database were used. Three feature sets were extracted from 5- and 0.5-min HRV segments: time-domain features, nonlinear-dynamics features and time-frequency features. The latter was achieved by using empirical mode decomposition (EMD) and discrete wavelet transform (DWT) methods. Normalized energies in important frequency bands of HRV signals were computed using time-frequency methods. ANOVA and t-test were used for statistical evaluations. Automatic sleep staging was based on HRV signal features. The ANOVA followed by a post hoc Bonferroni was used for individual feature assessment. Most features were beneficial for sleep staging. A t-test was used to compare the means of extracted features in 5- and 0.5-min HRV segments. The results showed that the extracted features means were statistically similar for a small number of features. A separability measure showed that time-frequency features, especially EMD features, had larger separation than others. There was not a sizable difference in separability of linear features between 5- and 0.5-min HRV segments but separability of nonlinear features, especially EMD features, decreased in 0.5-min HRV segments. HRV signal features were classified by linear discriminant (LD) and quadratic discriminant (QD) methods. Classification results based on features from 5-min segments surpassed those obtained from 0.5-min segments. The best result was obtained from features using 5-min HRV

  6. The Relationship between Cell Number, Division Behavior and Developmental Potential of Cleavage Stage Human Embryos: A Time-Lapse Study.

    Directory of Open Access Journals (Sweden)

    Xiangyi Kong

    Full Text Available Day 3 cleavage embryo transfer is routine in many assisted reproductive technology centers today. Embryos are usually selected according to cell number, cell symmetry and fragmentation for transfer. Many studies have showed the relationship between cell number and embryo developmental potential. However, there is limited understanding of embryo division behavior and their association with embryo cell number and developmental potential. A retrospective and observational study was conducted to investigate how different division behaviors affect cell number and developmental potential of day 3 embryos by time-lapse imaging. Based on cell number at day 3, the embryos (from 104 IVF/intracytoplasmic sperm injection (ICSI treatment cycles, n = 799 were classified as follows: less than 5 cells (10C; n = 42. Division behavior, morphokinetic parameters and blastocyst formation rate were analyzed in 5 groups of day 3 embryos with different cell numbers. In 10C embryos increased compared to 7-8C embryos (45.8%, 33.3% vs. 11.1%, respectively. In ≥5C embryos, FR and DC significantly reduced developmental potential, whereas 10C. In NB embryos, the cell cycle elongation or shortening was the main cause for abnormally low or high cell number, respectively. After excluding embryos with abnormal division behaviors, the developmental potential, implantation rate and live birth rate of day 3 embryos increased with cell number.

  7. Identification and validation of reference genes for qRT-PCR studies of the obligate aphid pathogenic fungus Pandora neoaphidis during different developmental stages.

    Directory of Open Access Journals (Sweden)

    Shutao Zhang

    Full Text Available The selection of stable reference genes is a critical step for the accurate quantification of gene expression. To identify and validate the reference genes in Pandora neoaphidis-an obligate aphid pathogenic fungus-the expression of 13classical candidate reference genes were evaluated by quantitative real-time reverse transcriptase polymerase chain reaction(qPCR at four developmental stages (conidia, conidia with germ tubes, short hyphae and elongated hyphae. Four statistical algorithms, including geNorm, NormFinder, BestKeeper and Delta Ct method were used to rank putative reference genes according to their expression stability and indicate the best reference gene or combination of reference genes for accurate normalization. The analysis of comprehensive ranking revealed that ACT1and 18Swas the most stably expressed genes throughout the developmental stages. To further validate the suitability of the reference genes identified in this study, the expression of cell division control protein 25 (CDC25 and Chitinase 1(CHI1 genes were used to further confirm the validated candidate reference genes. Our study presented the first systematic study of reference gene(s selection for P. neoaphidis study and provided guidelines to obtain more accurate qPCR results for future developmental efforts.

  8. Identification and validation of reference genes for qRT-PCR studies of the obligate aphid pathogenic fungus Pandora neoaphidis during different developmental stages.

    Science.gov (United States)

    Zhang, Shutao; Chen, Chun; Xie, Tingna; Ye, Sudan

    2017-01-01

    The selection of stable reference genes is a critical step for the accurate quantification of gene expression. To identify and validate the reference genes in Pandora neoaphidis-an obligate aphid pathogenic fungus-the expression of 13classical candidate reference genes were evaluated by quantitative real-time reverse transcriptase polymerase chain reaction(qPCR) at four developmental stages (conidia, conidia with germ tubes, short hyphae and elongated hyphae). Four statistical algorithms, including geNorm, NormFinder, BestKeeper and Delta Ct method were used to rank putative reference genes according to their expression stability and indicate the best reference gene or combination of reference genes for accurate normalization. The analysis of comprehensive ranking revealed that ACT1and 18Swas the most stably expressed genes throughout the developmental stages. To further validate the suitability of the reference genes identified in this study, the expression of cell division control protein 25 (CDC25) and Chitinase 1(CHI1) genes were used to further confirm the validated candidate reference genes. Our study presented the first systematic study of reference gene(s) selection for P. neoaphidis study and provided guidelines to obtain more accurate qPCR results for future developmental efforts.

  9. Nbn and atm cooperate in a tissue and developmental stage-specific manner to prevent double strand breaks and apoptosis in developing brain and eye.

    Directory of Open Access Journals (Sweden)

    Paulo M G Rodrigues

    Full Text Available Nibrin (NBN or NBS1 and ATM are key factors for DNA Double Strand Break (DSB signaling and repair. Mutations in NBN or ATM result in Nijmegen Breakage Syndrome and Ataxia telangiectasia. These syndromes share common features such as radiosensitivity, neurological developmental defects and cancer predisposition. However, the functional synergy of Nbn and Atm in different tissues and developmental stages is not yet understood. Here, we show in vivo consequences of conditional inactivation of both genes in neural stem/progenitor cells using Nestin-Cre mice. Genetic inactivation of Atm in the central nervous system of Nbn-deficient mice led to reduced life span and increased DSBs, resulting in increased apoptosis during neural development. Surprisingly, the increase of DSBs and apoptosis was found only in few tissues including cerebellum, ganglionic eminences and lens. In sharp contrast, we showed that apoptosis associated with Nbn deletion was prevented by simultaneous inactivation of Atm in developing retina. Therefore, we propose that Nbn and Atm collaborate to prevent DSB accumulation and apoptosis during development in a tissue- and developmental stage-specific manner.

  10. Youth participation in organized and informal sports activities across childhood and adolescence: exploring the relationships of motivational beliefs, developmental stage and gender.

    Science.gov (United States)

    Dawes, Nickki Pearce; Vest, Andrea; Simpkins, Sandra

    2014-08-01

    Involvement in physically active pursuits, such as sports, contributes to achieving and maintaining good emotional and physical health. The central goal of this article was to examine the longitudinal relationships between participation (i.e., time spent in the activities) in organized and informal sports contexts and motivational beliefs, and factors that might impact these relationships, such as developmental stage and gender. The data for the current study were drawn from the childhood and beyond longitudinal study, which utilized a cohort sequential design with data collected on three cohorts across four waves. The current study sample included 986 European American youth (51 % female), who t were mostly from working- and middle-class families. Self-report questionnaires were used to collect data from the youth about their participation in sports and their motivational beliefs (i.e., value and perceptions of competence) about this activity. Structural equation modeling was used to examine the relationships between participation and motivational beliefs across childhood and adolescence. The results provide some support for a model of reciprocal relationships between participation and motivational beliefs in organized and informal sports activities. These relationships between participation and motivational beliefs did not vary significantly based on developmental stage or by gender. Overall, the findings suggest that participation in organized and informal sports contexts may be fostered by supporting the development of positive motivational beliefs about the activities across developmental periods.

  11. Impact of a Teacher-as-Coach Model: Improving Paraprofessionals Fidelity of Implementation of Discrete Trial Training for Students with Moderate-to-Severe Developmental Disabilities

    Science.gov (United States)

    Mason, Rose A.; Schnitz, Alana G.; Wills, Howard P.; Rosenbloom, Raia; Kamps, Debra M.; Bast, Darcey

    2017-01-01

    Ensuring educational progress for students with moderate-to-severe developmental disabilities requires exposure to well executed evidence-based practices. This necessitates that the special education workforce, including paraprofessionals, be well-trained. Yet evidence regarding effective training mechanisms for paraprofessionals is limited. A…

  12. Do Developmental Mathematics Programs Have a Causal Impact on Student Retention? An Application of Discrete-Time Survival and Regression-Discontinuity Analysis

    Science.gov (United States)

    Lesik, Sally A.

    2007-01-01

    The impact of academic programs--such as developmental mathematics programs--on student retention, has been a controversial topic for administrators, policy makers, and faculty in higher education. Despite deep interest in the effectiveness of these programs in retaining students, scholars have been unable to determine whether such programs have a…

  13. NF-Y recruits both transcription activator and repressor to modulate tissue- and developmental stage-specific expression of human γ-globin gene.

    Directory of Open Access Journals (Sweden)

    Xingguo Zhu

    Full Text Available The human embryonic, fetal and adult β-like globin genes provide a paradigm for tissue- and developmental stage-specific gene regulation. The fetal γ-globin gene is expressed in fetal erythroid cells but is repressed in adult erythroid cells. The molecular mechanism underlying this transcriptional switch during erythroid development is not completely understood. Here, we used a combination of in vitro and in vivo assays to dissect the molecular assemblies of the active and the repressed proximal γ-globin promoter complexes in K562 human erythroleukemia cell line and primary human fetal and adult erythroid cells. We found that the proximal γ-globin promoter complex is assembled by a developmentally regulated, general transcription activator NF-Y bound strongly at the tandem CCAAT motifs near the TATA box. NF-Y recruits to neighboring DNA motifs the developmentally regulated, erythroid transcription activator GATA-2 and general repressor BCL11A, which in turn recruit erythroid repressor GATA-1 and general repressor COUP-TFII to form respectively the NF-Y/GATA-2 transcription activator hub and the BCL11A/COUP-TFII/GATA-1 transcription repressor hub. Both the activator and the repressor hubs are present in both the active and the repressed γ-globin promoter complexes in fetal and adult erythroid cells. Through changes in their levels and respective interactions with the co-activators and co-repressors during erythroid development, the activator and the repressor hubs modulate erythroid- and developmental stage-specific transcription of γ-globin gene.

  14. An Electro-Physiological Temporal Principal Component Analysis of Processing Stages of Number Comparison in Developmental Dyscalculia

    Science.gov (United States)

    Soltesz, Fruzsina; Szucs, Denes

    2009-01-01

    Developmental dyscalculia (DD) still lacks a generally accepted definition. A major problem is that the cognitive component processes contributing to arithmetic performance are still poorly defined. By a reanalysis of our previous event-related brain potential (ERP) data (Soltesz et al., 2007) here our objective was to identify and compare…

  15. A new psammosteid (Agnatha, Heterostraci from the Amata Regional Stage of the Main Devonian Field and morpho-histological types of discrete micromeric elements in the family Psammosteidae

    Directory of Open Access Journals (Sweden)

    Vadim N. Glinskiy

    2017-05-01

    Full Text Available In memory of an outstanding palaeoichthyologist Elga Mark-Kurik The range of diversity of psammosteids from the family Psammosteidae is still poorly known. Here a new species, Psammosteus ramosus sp. nov. Glinskiy, from the Amata Regional Stage of the Main Devonian Field is described. Its morphology, ornamentation, histology of exoskeletal plates, and micromeric elements are compared with those of other representatives of the family Psammosteidae. The comparison shows a close relationship of the new species with Psammosteus falcatus Obruchev, P. kiaeri Halstead Tarlo and P. pectinatus Obruchev, a group of species that is significantly different from other representatives of the genus Psammosteus and constitutes a separate evolutionary lineage. On the basis of morphological and histological features we here differentiate in the fields of tesserae of Psammosteidae the discrete micromeric elements of the ‘basic type’, known in Psammosteus bergi (Obruchev, P. levis Obruchev, P. livonicus Obruchev, P. maeandrinus Agassiz, P. megalopteryx (Trautschold, P. praecursor Obruchev and Karelosteus weberi Obruchev, and micromeric elements of the ‘progressive type’, known in Psammosteus falcatus, P. cf. kiaeri and P. ramosus sp. nov. Glinskiy.

  16. Characteristics of mentalization patterns in parents of children with difficulties in realizing developmental objectives of the latency stage - qualitative analysis results.

    Science.gov (United States)

    Dejko, Karolina; Janusz, Bernadetta; Treger, Bartosz

    2016-01-01

    The aim of the study was to answer the question about the ability to mentalize emotional states in parents of children with difficulties in realizing developmental objectives of the latency stage. The research was exploratory in nature; the aim was formulated on the basis of notions from the field literature indicating a correlation between the attachment style and the ability to mentalize in the parents and psychosocial functioning of their children. The structured Adult Attachment Interview (AAI) was used as the main tool for the research. The analysis was performed with the Reflective Functioning Scale. Total of 9 narrations obtained through AAI were subjected to qualitative analysis. The conducted analysis showed that parents of children with difficulties in realizing developmental objectives of the latency stage are characterized by reduced mentalization skills. The mentalization pattern isolated in the analysis, characteristic for the studied group encompasses the tendency towards idealization, generalization, describing the relation at the behavioural level and avoidance of reflecting upon mental states experienced in the context of early attachment relations, and the lack of coherence. Difficulties in mentalization of relationships mainly concern the relation with the mother. Relations established later in life are better mentalized than the early relations with parents. Observed disturbance in mentalization may suggest possible disturbances in the process of reflecting and containing in the early developmental stages of the examined persons. Mentalization skills were developed later in life of the examined persons. Idealization turned out to be the process that is most impacting and interfering with free reflections upon one's own emotions and emotions of the others (including those of one's own child).

  17. Linking ontogeny and tissue regeneration: a study on tissue damage and wound healing in carp in connection to the developmental stage

    DEFF Research Database (Denmark)

    Nielsen, Michael Engelbrecht; Schmidt, Jacob; Ingerslev, Hans-Christian

    regeneration since its genome is well-described and it is easy visually to follow the wound healing. In this study, carps were physically damaged in the musculature using sterile needles at day 10, 16, 24, 47 and 94 post hatch. Muscle tissue samples were subsequently taken at day 1, 3 and 7 post damage...... healing and tissue regeneration, the developmental stage of the individual may influence the immune reaction initiated following damage and thus the proliferative responses, which usually cross-talk with the immune system. Common carp (Cyprinus carpio) is an excellent fish specie to study tissue...

  18. Genotoxic, cytotoxic, developmental and survival effects of tritiated water in the early life stages of the marine mollusc, Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Hagger, Josephine A. [School of Biological Sciences, University of Plymouth, Drake Circus, Devon, Plymouth PL4 8AA (United Kingdom); Atienzar, Franck A. [School of Biological Sciences, University of Plymouth, Drake Circus, Devon, Plymouth PL4 8AA (United Kingdom); Jha, Awadhesh N. [School of Biological Sciences, University of Plymouth, Drake Circus, Devon, Plymouth PL4 8AA (United Kingdom)]. E-mail: ajha@plymouth.ac.uk

    2005-09-10

    Using an integrated approach linking different levels of biological organisation, the genotoxic, cytotoxic, developmental and survival impact of tritiated water (HTO) were investigated in the embryo-larvae of marine mollusc Mytilus edulis. One-hour-old embryos were exposed to a range of concentrations (0.37-370 kBq ml{sup -1}) of HTO, which delivered a dose between 0.02 and 21.41 mGy over the exposure period for different end points. Detrimental effects, if any, were monitored at different levels of biological organisation (i.e. DNA, chromosomal, cellular and individual). Genotoxic effects were assessed using molecular and cytogenetic approaches which included analysis of random amplified polymorphic DNA (RAPD), induction of sister chromatid exchanges (SCEs) and chromosomal aberrations (Cabs). Cytotoxic effects were evaluated by determining the proliferative rate index (PRI) of the embryo-larval cells. Developmental and survival effects were also monitored every 24 h up to 72 h. Results in general indicated that HTO significantly increased cytogenetic damage, cytotoxicity, developmental abnormalities and mortality of the embryo-larvae as a function of concentration or radiation dose. The analysis of RAPD profiles also revealed qualitative effects in the HTO exposed population compared to controls. However, while the embryo-larvae showed dose or concentration dependent effects for mortality, developmental abnormalities and induction of SCEs, the dose-dependent effects were not apparent for Cabs and PRI at higher doses. The study contributes to our limited understanding of the impact of environmentally relevant radionuclides on non-human biota and emphasises the need for further investigations to elucidate potentially long term damage induced by persistent, low levels of other radionuclides on commercially and ecologically important species, in order to protect human and ecosystem health.

  19. Two-Stage Progressive Femoral Lowering Followed by Cementless Total Hip Arthroplasty for Treating Crowe IV-Hartofilakidis Type 3 Developmental Dysplasia of the Hip.

    Science.gov (United States)

    Binazzi, Roberto

    2015-05-01

    High developmental dysplasia of the hip is commonly treated with total hip arthroplasty and shortening osteotomy. We present a two stage technique, consisting of progressive femoral lowering followed by total hip arthroplasty. The clinico-radiographic results of eleven patients (twelve hips) who were operated on with the two-stage technique were evaluated at a mean follow-up of 11 ± 5 years. At the final follow-up, ten patients (eleven hips) had a mean Harris hip score of 85 ± 5 points with no implant loosening. One patient (one hip) was revised at 5 years due to infection. No neurovascular complications were observed in any patients. With this technique, we could place the cup in the anatomical position and obtain complete limb symmetry with excellent clinical results at long-term. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. The DNA methylation status of MyoD and IGF-I genes are correlated with muscle growth during different developmental stages of Japanese flounder (Paralichthys olivaceus).

    Science.gov (United States)

    Huang, Yajuan; Wen, Haishen; Zhang, Meizhao; Hu, Nan; Si, Yufeng; Li, Siping; He, Feng

    2018-05-01

    Many genes related to muscle growth modulate myoblast proliferation and differentiation and promote muscle hypertrophy. MyoD is a myogenic determinant that contributes to myoblast determination, and insulin-like growth factor 1 (IGF-I) interacts with MyoD to regulate muscle hypertrophy and muscle mass. In this study, we aimed to assess DNA methylation and mRNA expression patterns of MyoD and IGF-I during different developmental stages of Japanese flounder, and to examine the relationship between MyoD and IGF-I gene. DNA and RNA were extracted from muscles, and DNA methylation of MyoD and IGF-I promoter and exons was detected by bisulfite sequencing. The relative expression of MyoD and IGF-I was measured by quantitative polymerase chain reaction. IGF-I was measured by radioimmunoassay. Interestingly, the lowest expression of MyoD and IGF-I emerged at larva stage, and the mRNA expression was negatively associated with methylation. We hypothesized that many skeletal muscle were required to complete metamorphosis; thus, the expression levels of MyoD and IGF-I genes increased from larva stage and then decreased. The relative expression levels of MyoD and IGF-I exhibited similar patterns, suggesting that MyoD and IGF-I regulated muscle growth through combined effects. Changes in the concentrations of IGF-I hormone were similar to those of IGF-I gene expression. Our results the mechanism through which MyoD and IGF-I regulate muscle development and demonstrated that MyoD interacted with IGF-I to regulate muscle growth during different developmental stages. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Changes in hippocampal neurons and memory function during the developmental stage of newborn rats with hypoxic-ischemic encephalopathy

    Institute of Scientific and Technical Information of China (English)

    Chuanjun Liu; Yue Li; Huiying Gao

    2006-01-01

    BACKGROUND: Under the normal circumstance, there exist some synapses with inactive functions in central nervous system (CNS), but these functions are activated following nerve injury. At the early stage of brain injury, the abnormal functions of brain are varied, and they have very strong plasticity and are corrected easily.OBJECTTVE: To observe the changes of neuronal morphology in hippocampal CA1 region and memory function in newborn rats with hypoxic-ischemic encephalopathy(HIE) from ischemia 6 hours to adult.DESTGN: Completely randomized grouping, controlled experiment.SETTING: Taian Health Center for Women and Children; Taishan Medical College.MATERTALS: Altogether 120 seven-day-old Wistar rats, of clean grade, were provided by the Experimental Animal Center, Shandong University of Traditional Chinese Medicine. Synaptophysin (SYN) polyclonal antibody was provided by Maixin Biological Company, Fuzhou.METHODS: This experiment was carried out in the Laboratory of Morphology, Taishan Medical College between October 2000 and December 2003. ① The newborn rats were randomly divided into 2 groups: model group and control group, 60 rats in each group. Five rats were chosen from each group at postoperative 6 hours, 24hours, 72 hours, 7 days, 2 weeks and 3 weeks separately for immunohistochemical staining. Fifteen newborn rats were chosen from each group at postoperative 4 weeks and 2 months separately for testing memory ability(After test, 5 rats from each group were sacrificed and used for immunohistochemical staining) ② The right common carotid artery of newborn rats of model group was ligated under the sthetized status. After two hours of incubation, the rats were placed for 2 hours in a container filled with nitrogen oxygen atmosphere containing 0.08 volume fraction of oxygen, thus, HIE models were created; As for the newborn rats in the control group, only blood vessels were isolated, and they were not ligated and hypoxia-treated. ③Thalamencephal tissue

  2. Heat-Treatment-Responsive Proteins in Different Developmental Stages of Tomato Pollen Detected by Targeted Mass Accuracy Precursor Alignment (tMAPA).

    Science.gov (United States)

    Chaturvedi, Palak; Doerfler, Hannes; Jegadeesan, Sridharan; Ghatak, Arindam; Pressman, Etan; Castillejo, Maria Angeles; Wienkoop, Stefanie; Egelhofer, Volker; Firon, Nurit; Weckwerth, Wolfram

    2015-11-06

    Recently, we have developed a quantitative shotgun proteomics strategy called mass accuracy precursor alignment (MAPA). The MAPA algorithm uses high mass accuracy to bin mass-to-charge (m/z) ratios of precursor ions from LC-MS analyses, determines their intensities, and extracts a quantitative sample versus m/z ratio data alignment matrix from a multitude of samples. Here, we introduce a novel feature of this algorithm that allows the extraction and alignment of proteotypic peptide precursor ions or any other target peptide from complex shotgun proteomics data for accurate quantification of unique proteins. This strategy circumvents the problem of confusing the quantification of proteins due to indistinguishable protein isoforms by a typical shotgun proteomics approach. We applied this strategy to a comparison of control and heat-treated tomato pollen grains at two developmental stages, post-meiotic and mature. Pollen is a temperature-sensitive tissue involved in the reproductive cycle of plants and plays a major role in fruit setting and yield. By LC-MS-based shotgun proteomics, we identified more than 2000 proteins in total for all different tissues. By applying the targeted MAPA data-processing strategy, 51 unique proteins were identified as heat-treatment-responsive protein candidates. The potential function of the identified candidates in a specific developmental stage is discussed.

  3. [The content of mineral elements in Camellia olei fera ovary at pollination and fertilization stages determined by auto discrete analyzers and atomic absorption spectrophotometer].

    Science.gov (United States)

    Zou, Feng; Yuan, De-Yi; Gao, Chao; Liao, Ting; Chen, Wen-Tao; Han, Zhi-Qiang; Zhang, Lin

    2014-04-01

    In order to elucidate the nutrition of Camellia olei fera at pollination and fertilization stages, the contents of mineral elements were determined by auto discrete analyzers and atomic absorption spectrophotometer, and the change in the contents of mineral elements was studied and analysed under the condition of self- and cross-pollination. The results are showed that nine kinds of mineral elements contents were of "S" or "W" type curve changes at the pollination and fertilization stages of Camellia olei fera. N, K, Zn, Cu, Ca, Mn element content changes showed "S" curve under the self- and out-crossing, the content of N reaching the highest was 3.445 8 mg x g(-1) in self-pollination of 20 d; K content reaching the highest at the cross-pollination 20 d was 6.275 5 mg x g(-1); Zn content in self-pollination of 10 d reaching the highest was 0.070 5 mg x g(-1); Cu content in the cross-pollination of 5 d up to the highest was 0.061 0 mg x g(-1); Ca content in the cross-pollination of 15 d up to the highest was 3.714 5 mg x g(-1); the content of Mn reaching the highest in self-pollination 30 d was 2. 161 5 mg x g(-1). Fe, P, Mg element content changes was of "S" type curve in selfing and was of "W" type curve in outcrossing, Fe content in the self-pollination 10 d up to the highest was 0.453 0 mg x g(-1); P content in self-pollination of 20 d reaching the highest was 6.731 8 mg x g(-1); the content of Mg up to the highest in self-pollination 25 d was 2.724 0 mg x g(-1). The results can be used as a reference for spraying foliar fertilizer, and improving seed setting rate and yield in Camellia olei fera.

  4. Spaceflight Activates Protein Kinase C Alpha Signaling and Modifies the Developmental Stage of Human Neonatal Cardiovascular Progenitor Cells.

    Science.gov (United States)

    Baio, Jonathan; Martinez, Aida F; Bailey, Leonard; Hasaniya, Nahidh; Pecaut, Michael J; Kearns-Jonker, Mary

    2018-02-12

    Spaceflight impacts cardiovascular function in astronauts; however, its impact on cardiac development and the stem cells that form the basis for cardiac repair is unknown. Accordingly, further research is needed to uncover the potential relevance of such changes to human health. Using simulated microgravity (SMG) generated by two-dimensional clinorotation and culture aboard the International Space Station (ISS), we assessed the effects of mechanical unloading on human neonatal cardiovascular progenitor cell (CPC) developmental properties and signaling. Following 6-7 days of SMG and 12 days of ISS culture, we analyzed changes in gene expression. Both environments induced the expression of genes that are typically associated with an earlier state of cardiovascular development. To understand the mechanism by which such changes occurred, we assessed the expression of mechanosensitive small RhoGTPases in SMG-cultured CPCs and observed decreased levels of RHOA and CDC42. Given the effect of these molecules on intracellular calcium levels, we evaluated changes in noncanonical Wnt/calcium signaling. After 6-7 days under SMG, CPCs exhibited elevated levels of WNT5A and PRKCA. Similarly, ISS-cultured CPCs exhibited elevated levels of calcium handling and signaling genes, which corresponded to protein kinase C alpha (PKCα), a calcium-dependent protein kinase, activation after 30 days. Akt was activated, whereas phosphorylated extracellular signal-regulated kinase levels were unchanged. To explore the effect of calcium induction in neonatal CPCs, we activated PKCα using hWnt5a treatment on Earth. Subsequently, early cardiovascular developmental marker levels were elevated. Transcripts induced by SMG and hWnt5a-treatment are expressed within the sinoatrial node, which may represent embryonic myocardium maintained in its primitive state. Calcium signaling is sensitive to mechanical unloading and directs CPC developmental properties. Further research both in space and on Earth

  5. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2011-01-01

    The objectives of Discrete Mathematics (IDISM2) are: The introduction of the mathematics needed for analysis, design and verification of discrete systems, including the application within programming languages for computer systems. Having passed the IDISM2 course, the student will be able...... to accomplish the following: -Understand and apply formal representations in discrete mathematics. -Understand and apply formal representations in problems within discrete mathematics. -Understand methods for solving problems in discrete mathematics. -Apply methods for solving problems in discrete mathematics......; construct a finite state machine for a given application. Apply these concepts to new problems. The teaching in Discrete Mathematics is a combination of sessions with lectures and students solving problems, either manually or by using Matlab. Furthermore a selection of projects must be solved and handed...

  6. Use of infrared imaging to predict the developmental stages and differences in chicken embryos exposed to different photoperiods

    Science.gov (United States)

    Frederick, Rebecca A.; Hsieh, Sheng-Jen; Palomares, Benjamin Giron

    2012-06-01

    Monitoring development of chicken embryos allows determination of when an egg is not developing and when eggs are close to hatching for more efficient production. Research has been conducted on the effects of temperature fluctuations and light exposure on embryo development; similarities between chicken and mammal embryos; and the use of MRI, tomography, and ultrasound to view specific areas and processes within the embryo. However, there has been little exploration of the use of infrared imaging as a non-destructive method for analyzing and predicting embryonic development. In this study, we built an automated loading system for image acquisition. Pilot experiments were conducted to determine the overall scanning time and scanning frequency. A batch of fertilized eggs was scanned each day as the embryos continued to grow. The captured images were analyzed and categorized into three stages: Stage 1 (days 1 to 7), Stage 2 (days 8 to 14), and Stage 3 (days 15 to 21). The temperature data abstracted from the captured images were divided into two groups. Group 1, consisting of two-thirds of the data, was used to construct a model. Group 2, consisting of one-third of the data, was used to evaluate the predictive accuracy of the model. A three-layer artificial neural network model was developed to predict embryo development stage given a temperature profile. Results suggest that the neural network model is sufficient to predict embryo development stage with good accuracy of 75%. Accuracy can likely be improved if more data sets for each development stage are available.

  7. Effect of Domestic Processing Methods on Dry Matter, Total Sugar, Phenolics and Mineral Composition in Different Developmental Stages of Parkia roxburghii G. (Don. Pods

    Directory of Open Access Journals (Sweden)

    Jekendra Singh SALAM

    2013-02-01

    Full Text Available Parkia roxburghii is considered delicious in the Northeastern part of India, especially in the state of Manipur. Though it is widely used, information about the biochemical composition and its changes, after processing, is hardly available. In the present experiment, effect of processing methods on dry matter, soluble sugar, phenolics and mineral composition in different developmental stages of P. roxburghii pods were studied. Total soluble sugar (TSS, total phenols (TP, and orthodihydric phenols (ODHP were determined as per the methods of Morris (1948, Bray and Thorpe (1954 and Mahadevan and Sridhar (1986. Sodium (Na, potassium (K, sulphur (S and phosphorus (P were estimated as per the procedures of Tandon (1993. Calcium (Ca, magnesium (Mg, manganese (Mn, zinc (Zn, iron (Fe, copper (Cu and cobalt (Co were analyzed in an atomic absorption spectrophotometer. Processing methods reduced dry matter, soluble sugar and phenolics in all the stages of the pod. TP and ODHP lost up to the extent of 72.78% in tender stage due to ordinary cooking, while higher loss of ODHP recorded in immature stage of the pod due to pressure cooking. Ca, Mg, K and Zn in different stages were found to be affected significantly by different methods of cooking, while no such changes were observed in case of S, P, Fe, Mn and Cu. The level of iron amongst the micro minerals is appreciably high recording up to 51.0 mg/100 g in the immature stage of the pod. As iron, zinc and manganese are antioxidant micronutrients, their higher presence in P. roxburghii might be of some nutritional importance.

  8. Dynamic regulation of mRNA and miRNA associated with the developmental stages of skin pigmentation in Japanese ornamental carp.

    Science.gov (United States)

    Tian, Xue; Pang, Xiaolei; Wang, Liangyan; Li, Mengrong; Dong, Chuanju; Ma, Xiao; Wang, Lei; Song, Dongying; Feng, Jianxin; Xu, Peng; Li, Xuejun

    2018-04-20

    The Japanese ornamental carp (Cyprinus carpio var. Koi) is famous for multifarious colors and patterns, making it commonly culture and trade across the world. Although functional genes and inheritance of color traits have been commonly studied, seldom attentions were focused on the genetic regulation during the developmental process of pigmentation. To better understand the mechanism of skin color development, we observed the morphogenesis of pigment cells during the post-embryonic stages and analysed the temporal expression pattern of mRNAs/miRNAs profiles in four distinct developmental stages. 59 and 103 differentially expressed genes/miRNAs (DEGs/DEMs) associated with pigmentation and skin were identified, including pax7, mitf, tyr, tyrp1, etc., and the highest DEGs were detected at 11 days post hatching (dph). In addition, the functional characteristics of mRNAs/miRNAs associated with pteridine and carotenoid pathway were also examined. Furthermore, 65 miRNA-mRNA interaction pairs related to pigmentation, pteridines and carotenoids metabolism were detected between different stages. Interestingly, the largest pairs appeared in the transition from 11 dph to 48 dph, which had the similar trend with DEGs further manifesting the importance of 11 dph. This study produced a comprehensive programme of DEGs/DEMs during color development, which will provide resources to understand the regulation mechanism in color formation. The understanding of genetic basis in color formation might promote the production and breeding of the Koi carp. Copyright © 2017. Published by Elsevier B.V.

  9. Evaluation of Suitable Reference Genes for Normalization of qPCR Gene Expression Studies in Brinjal (Solanum melongena L.) During Fruit Developmental Stages.

    Science.gov (United States)

    Kanakachari, Mogilicherla; Solanke, Amolkumar U; Prabhakaran, Narayanasamy; Ahmad, Israr; Dhandapani, Gurusamy; Jayabalan, Narayanasamy; Kumar, Polumetla Ananda

    2016-02-01

    Brinjal/eggplant/aubergine is one of the major solanaceous vegetable crops. Recent availability of genome information greatly facilitates the fundamental research on brinjal. Gene expression patterns during different stages of fruit development can provide clues towards the understanding of its biological functions. Quantitative real-time PCR (qPCR) has become one of the most widely used methods for rapid and accurate quantification of gene expression. However, its success depends on the use of a suitable reference gene for data normalization. For qPCR analysis, a single reference gene is not universally suitable for all experiments. Therefore, reference gene validation is a crucial step. Suitable reference genes for qPCR analysis of brinjal fruit development have not been investigated so far. In this study, we have selected 21 candidate reference genes from the Brinjal (Solanum melongena) Plant Gene Indices database (compbio.dfci.harvard.edu/tgi/plant.html) and studied their expression profiles by qPCR during six different fruit developmental stages (0, 5, 10, 20, 30, and 50 days post anthesis) along with leaf samples of the Pusa Purple Long (PPL) variety. To evaluate the stability of gene expression, geNorm and NormFinder analytical softwares were used. geNorm identified SAND (SAND family protein) and TBP (TATA binding protein) as the best pairs of reference genes in brinjal fruit development. The results showed that for brinjal fruit development, individual or a combination of reference genes should be selected for data normalization. NormFinder identified Expressed gene (expressed sequence) as the best single reference gene in brinjal fruit development. In this study, we have identified and validated for the first time reference genes to provide accurate transcript normalization and quantification at various fruit developmental stages of brinjal which can also be useful for gene expression studies in other Solanaceae plant species.

  10. Studies on the Susceptibility of Different Developmental Stages of [Bemisia tabaci (Gennadius] to Pyriproxyfen and Citowett Oil

    Directory of Open Access Journals (Sweden)

    sedighe ashtari

    2018-02-01

    Full Text Available Introduction: Bemisia tabaci is highly polyphagous herbivore. This is one of the most important cotton pests throughout the world. Bemisia tabaci causes noticeable damage to quality and quantity of cotton yield. Due to its special habitat, the present efforts to control of the pest have focused on the application of chemical insecticides. It is well established that the overuse and misuse of these compounds can lead to environemntal disasters and development of resistance. Therefore, undertakening research for a safe and environment- compatible method of control has been warranted. In our research, the degree of sensitivity of different life stages of B. tabaci to a juvenile hormone analogue compound and citowett oil was evaluated. Materials and Methods: For this purpose, specimens were collected from contaminated tomato and tobacco flowerpots in the greenhouse of the Faculty of Agriculture at Urmia University. After immersion of leaves in the pesticide solutions, the sensitivity of different life stages was evaluated. The purpose of this test is to determine the range of concentrations of insecticides which would cause 25-75 percent death rate. The main concentrations were calculated by the concentration of preliminary experiments.The control mortality was corrected using Abbott's formula. Results and Discussion: At the termination of experiments the following results were obtained: in all of the treatments, nymph, pupa and egg stages were the most sensitive ones to this compound, respectively, because the juvenile hormone analogue affected the egg and the immature stages but did not affect the adult insects. In the citowett oil treatment nymph, pupa and egg were the most sensitive stages and the adult insect was the most resistant one. The LC50 value of pyriproxyfen after 24 hours for the adult, egg, nymph along with pupa stages (immature stages were 973.1530, 45.045 and 11.4468 ppm, respectively. The LC50 value of citowett oil after 24 hour

  11. Oxygen consumption rate and Na+/K+-ATPase activity in early developmental stages of the sea urchin Paracentrotus lividus Lam.

    Science.gov (United States)

    Tomšić, Sanja; Stanković, Suzana; Lucu, Čedomil

    2011-09-01

    Changes in oxygen consumption rate and Na+/K+-ATPase activity during early development were studied in the sea urchin Paracentrotus lividus Lam. The oxygen consumption rate increased from 0.12 μmol O2 mg protein-1 h-1 in unfertilized eggs to 0.38 μmol O2 mg protein-1 h-1 25 min after fertilization. Specific activity of the Na+/K+-ATPase was significantly stimulated after fertilization, ranging up to 1.07 μmol Pi h-1 mg protein-1 in the late blastula stage and slightly lower values in the early and late pluteus stages.

  12. Influence of developmental stage and genotype on liver mRNA levels among wild, domesticated, and hybrid rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    White, Samantha L; Sakhrani, Dionne; Danzmann, Roy G; Devlin, Robert H

    2013-10-02

    Release of domesticated strains of fish into nature may pose a threat to wild populations with respect to their evolved genetic structure and fitness. Understanding alterations that have occurred in both physiology and genetics as a consequence of domestication can assist in evaluating the risks posed by introgression of domesticated genomes into wild genetic backgrounds, however the molecular causes of these consequences are currently poorly defined. The present study has examined levels of mRNA in fast-growing pure domesticated (D), slow-growing age-matched pure wild (Wa), slow-growing size-matched pure wild (Ws), and first generation hybrid cross (W/D) rainbow trout (Oncorhynchus mykiss) to investigate the influence of genotype (domesticated vs. wild, and their interactions in hybrids) and developmental stage (age- or size-matched animals) on genetic responses (i.e. dominant vs. recessive) and specific physiological pathways. Highly significant differences in mRNA levels were found between domesticated and wild-type rainbow trout genotypes (321 mRNAs), with many mRNAs in the wild-domesticated hybrid progeny showing intermediate levels. Differences were also found between age-matched and size-matched wild-type trout groups (64 mRNAs), with unique mRNA differences for each of the wild-type groups when compared to domesticated trout (Wa: 114 mRNAs, Ws: 88 mRNAs), illustrating an influence of fish developmental stage affecting findings when used as comparator groups to other genotypes. Analysis of differentially expressed mRNAs (found for both wild-type trout to domesticated comparisons) among the genotypes indicates that 34.8% are regulated consistent with an additive genetic model, whereas 39.1% and 26.1% show a recessive or dominant mode of regulation, respectively. These molecular data are largely consistent with phenotypic data (growth and behavioural assessments) assessed in domesticated and wild trout strains. The present molecular data are concordant with

  13. Germ cell tumors in patients with disorders of sex development: Risk factors, initial developmental stages and targets for early diagnosis

    NARCIS (Netherlands)

    M.B.C.M. Cools (Martine)

    2006-01-01

    textabstractThis thesis describes the origin, identification and correct diagnosis of the earliest stages of malignant germ cell tumors, i.e. intra tubular germ cell neoplasia unclassified (ITGNU) and gonadoblastoma, in patients with disorders of sex development. Special attention is given to the

  14. Electron microscopic study of developmental stages of Rickettsiella phytoseiuli in Phytoseiulus persimilis Athias-Henriot (Gamasoidea:Phytoseiidae) mites.

    Science.gov (United States)

    Sutáková, G

    1988-01-01

    Rickettsiella phytoseiuli was found in great amounts in all tissues except of the nervous system of adult Phytoseiulus persimilis mites. Six morphologically different stages (dense, intermediate, bacterial, giant, crystal-forming and small dark particles) of R. phytoseiuli were detected. No rickettsiae were seen in the larvae and in phase 1 and 2 nymphae of these mites.

  15. Genome-Wide Analysis of the Expression of WRKY Family Genes in Different Developmental Stages of Wild Strawberry (Fragaria vesca Fruit.

    Directory of Open Access Journals (Sweden)

    Heying Zhou

    Full Text Available WRKY proteins play important regulatory roles in plant developmental processes such as senescence, trichome initiation and embryo morphogenesis. In strawberry, only FaWRKY1 (Fragaria × ananassa has been characterized, leaving numerous WRKY genes to be identified and their function characterized. The publication of the draft genome sequence of the strawberry genome allowed us to conduct a genome-wide search for WRKY proteins in Fragaria vesca, and to compare the identified proteins with their homologs in model plants. Fifty-nine FvWRKY genes were identified and annotated from the F. vesca genome. Detailed analysis, including gene classification, annotation, phylogenetic evaluation, conserved motif determination and expression profiling, based on RNA-seq data, were performed on all members of the family. Additionally, the expression patterns of the WRKY genes in different fruit developmental stages were further investigated using qRT-PCR, to provide a foundation for further comparative genomics and functional studies of this important class of transcriptional regulators in strawberry.

  16. Neonatal manipulation of oxytocin prevents lipopolysaccharide-induced decrease in gene expression of growth factors in two developmental stages of the female rat.

    Science.gov (United States)

    Bakos, Jan; Lestanova, Zuzana; Strbak, Vladimir; Havranek, Tomas; Bacova, Zuzana

    2014-10-01

    Oxytocin production and secretion is important for early development of the brain. Long-term consequences of manipulation of oxytocin system might include changes in markers of brain plasticity - cytoskeletal proteins and neurotrophins. The aim of the present study was (1) to determine whether neonatal oxytocin administration affects gene expression of nestin, microtubule-associated protein-2 (MAP-2), brain derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the brain of two developmental stages of rat and (2) to evaluate whether neonatal oxytocin administration protects against lipopolysaccharide (LPS) induced inflammation. Neonatal oxytocin did not prevent a decrease of body weight in the LPS treated animals. Oxytocin significantly increased gene expression of BDNF in the right hippocampus in 21-day and 2-month old rats of both sexes. Gene expression of NGF and MAP-2 significantly increased in males treated with oxytocin. Both, growth factors and intermediate filament-nestin mRNA levels, were reduced in females exposed to LPS. Oxytocin treatment prevented a decrease in the gene expression of only growth factors. In conclusion, neonatal manipulation of oxytocin has developmental and sex-dependent effect on markers of brain plasticity. These results also indicate, that oxytocin may be protective against inflammation particularly in females. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Content of fluorine in the developmental stages of some forest pests in the emission area of an aluminium plant. [Operophtera brumata; Aradus cinnamomeus

    Energy Technology Data Exchange (ETDEWEB)

    Mankovska, B

    1976-01-01

    Using the spectrometric method with the complex Zr (IV) and xylenol orange the fluorine was determined in the developmental stages of the Operophtera brumata Den. et Schiff. and Aradus cinnamomeus L. The difference when compared with the control areas is statistically significant in the 99% level of importance. Individuals of Aradus cinnamomeus L. from the emission area contained 593.60 mg/100 g dry matter; this is 200 times greater than the amount of fluorine as in the control area; 5.94 ..mu..g for 1 piece. Similarly, the caterpillars of Operophtera brumata Den. et Schiff. contained 300.11 mg/100 g dry matter. A spectacular rise of fluorine - 1.5 times was presented by laboratory reared individuals - 490.74 mg/100 g.

  18. The developmental stages of the middle phalanx of the third finger (MP3): a sole indicator in assessing the skeletal maturity?

    Science.gov (United States)

    Madhu, S; Hegde, Amitha M; Munshi, A K

    2003-01-01

    Assessment of skeletal maturity is an integral part of interceptive diagnosis and treatment planning. The present day methods of skeletal maturity assessment like the hand-wrist radiographs or cervical vertebrae radiographs are expensive, require elaborate equipment and accounts for high radiation exposure, especially for growing children. The present study was thus undertaken to provide a simple and practical method of skeletal maturity assessment using the developmental stages of the middle phalanx of the third finger (MP3) as seen on an IOPA film taken using a standard dental x-ray machine. The results of the study showed that this simple method was highly reliable and could be used as an alternative method to assess the skeletal maturity of growing children.

  19. Effects of the β-Adrenergic Agonist Cimaterol on Growth and Carcass Quality of Monozygotic Friesian Young Bulls at Three Developmental Stages

    DEFF Research Database (Denmark)

    Vestergaard, Mogens; Sommer, Mario; Klastrup, Signe

    1993-01-01

    of intake. The animals were slaughtered on day 90 of the treatment period. Without affecting feed intake, CIM treatment increased average daily gain (ADG) by 19% (Pcarcass gain, EUROP conformation and longissimus dorsi area were all...... in cuts from the hind region of the carcass. The percentage of carcass saleable meat increased (Panimals. The effects of cimaterol were evident in all three WG. The results show that cimaterol is effective in stimulating overall growth performance and improving carcass leanness......The objective was to investigate the effects of the β-adrenergic agonist cimaterol (CIM) on growth and carcass quality of Friesian young bulls at different developmental stages. The study comprised three liveweight groups (WG) each of four pairs of monozygotic twins. The average initial liveweight...

  20. Effects of Yamase climatic condition during the pollen mother cell developmental stage on concentrations of Cs and Sr in brown rice

    International Nuclear Information System (INIS)

    Yanai, Masumi; Kobayashi, Daisuke; Yamagami, Mutsumi; Takaku, Yuichi; Hisamatsu, Shun'ichi

    2007-01-01

    Effects of the Yamase climatic condition on the concentration of alkali metals and alkaline earth metals in brown rice were examined in relation to the soil-to-plant transfer factors of 137 Cs and 90 Sr. Rice plants (Oryza sativa L cv. Yumeakari) were cultivated in an artificial climate chamber, and exposed to a simulated Yamase condition for 3 or 7 d during the pollen mother cell developmental stage. In these simulated treatments, temperature and light intensity were set to 5degC lower and 50% lower than the respective control values. Fog was generated with visibility of 70±30 m. Concentrations of alkali metals, alkaline earth metals and the other minor elements in brown rice samples were analyzed. Measured Cs and Sr concentrations were found to be unaffected by the Yamase treatments, while concentrations of Fe, Cu, Zn and Mo were increased. (author)

  1. Physiological Responses of Bambara Groundnut (Vigna subterranea L. Verdc) to Short Periods of Water Stress During Different Developmental Stages

    OpenAIRE

    R. Vurayai; V. Emongor and B. Moseki

    2011-01-01

    The study was conducted to evaluate the responses of bambara groundnut (Vigna subterranea L. Verdc) to short periods of water stress imposed at different growth stages, and the recuperative ability of the species from drought stress. A major problem associated with Bambara groundnut production is its very low yields due to intra-seasonal and inter-seasonal variability in rainfall in semi-arid regions. The response pattern of physiological processes to water stress imposed at different growth ...

  2. Adolescent–Adult Discrepancies on the Eating Disorder Examination: A Function of Developmental Stage or Severity of Illness?

    Science.gov (United States)

    Loeb, Katharine L.; Jones, Jennifer; Roberto, Christina A.; Gugga, S. Sonia; Marcus, Sue M.; Attia, Evelyn; Walsh, B. Timothy

    2014-01-01

    Objective Across studies, adolescents score lower on measures of eating disorder pathology than adults, but it is unclear whether such findings reflect discrepancies inherent to site/study or true developmental differences. The aim of this study was to determine whether age predicts subscale and diagnostic scores of the Eating Disorder Examination (EDE) in adolescents and adults with anorexia nervosa (AN) admitted to a single research center within the same period of time. Method The sample consisted of 16 adolescent and 20 adult consecutive admissions to parallel, age-specific, research-based AN treatment programs. Participants completed a baseline evaluation at admission that included the EDE, depression measures, and global assessment of functioning scales. Results Age significantly predicted EDE scores in univariate regression analyses. However, in multivariate models that included severity indices of general and specific psychopathology as covariates, age was no longer a significant predictor of severity of eating disorder symptoms. Discussion This study adds to the growing body of data showing lower scores on the EDE for adolescents with AN relative to their adult counterparts, while eliminating potential site confounds. Results indicate that the higher adult scores may be carried in part by a more overall severe and chronic general clinical profile. PMID:21823141

  3. Effects of Helicoverpa armigera (Noctuidae, Lepidoptera) host stages on some developmental parameters of the uniparental endoparasitoid Meteorus pulchricornis (Braconidae, Hymenoptera).

    Science.gov (United States)

    Liu, Ya-Hui; Li, Bao-Ping

    2008-04-01

    A single choice test was performed to examine developmental strategies in the uniparental endoparasitoid Meteorus pulchricornis and its host, the cotton bollworm Helicoverpa armigera. The results support the dome-shaped model in which the fitness functions are 'dome-shaped' relative to size (and age) of host at parasitism. Older and, hence, larger host larvae were simply not better hosts for the developing parasitoids. Although parasitoid size (measured as cocoon weight and adult hind tibia length) was positively correlated with host instars at parasitism, parasitoids developing in larger hosts (L5 and L6) suffered much higher mortality than conspecifics developing in smaller hosts (L2-L4). Furthermore, egg-to-adult development time in M. pulchricornis was significantly longer in older host larvae (L4-L6) than in the younger. Performance of M. pulchricornis, as indicated by fitness-related traits, strongly suggests that the L3 host is the most suitable for survival, growth and development of the parasitoid, followed by both L2 and L4 hosts; whereas, L1, L5 and L6 are the least favourable hosts. The oviposition tendency of M. pulchricornis, represented by parasitism level, was not perfectly consistent with the performance of the offspring; L2-L4 hosts, although with the same parasitism level, had offspring parasitoids with differences in fitness-related performance. Larval development in Helicoverpa armigera was usually suspended, but occasionally advanced, in the final instar.

  4. Prochloraz and coumaphos induce different gene expression patterns in three developmental stages of the Carniolan honey bee (Apis mellifera carnica Pollmann).

    Science.gov (United States)

    Cizelj, Ivanka; Glavan, Gordana; Božič, Janko; Oven, Irena; Mrak, Vesna; Narat, Mojca

    2016-03-01

    The Carniolan honey bee, Apis mellifera carnica, is a Slovenian autochthonous subspecies of honey bee. In recent years, the country has recorded an annual loss of bee colonies through mortality of up to 35%. One possible reason for such high mortality could be the exposure of honey bees to xenobiotic residues that have been found in honey bee and beehive products. Acaricides are applied by beekeepers to control varroosis, while the most abundant common agricultural chemicals found in honey bee and beehive products are fungicides, which may enter the system when applied to nearby flowering crops and fruit plants. Acaricides and fungicides are not intrinsically highly toxic to bees but their action in combination might lead to higher honey bee sensitivity or mortality. In the present study we investigated the molecular immune response of honey bee workers at different developmental stages (prepupa, white-eyed pupa, adult) exposed to the acaricide coumaphos and the fungicide prochloraz individually and in combination. Expression of 17 immune-related genes was examined by quantitative RT-PCR. In treated prepupae downregulation of most immune-related genes was observed in all treatments, while in adults upregulation of most of the genes was recorded. Our study shows for the first time that negative impacts of prochloraz and a combination of coumaphos and prochloraz differ among the different developmental stages of honey bees. The main effect of the xenobiotic combination was found to be upregulation of the antimicrobial peptide genes abaecin and defensin-1 in adult honey bees. Changes in immune-related gene expression could result in depressed immunity of honey bees and their increased susceptibility to various pathogens. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2011-01-01

    ; construct a finite state machine for a given application. Apply these concepts to new problems. The teaching in Discrete Mathematics is a combination of sessions with lectures and students solving problems, either manually or by using Matlab. Furthermore a selection of projects must be solved and handed...... to accomplish the following: -Understand and apply formal representations in discrete mathematics. -Understand and apply formal representations in problems within discrete mathematics. -Understand methods for solving problems in discrete mathematics. -Apply methods for solving problems in discrete mathematics...... to new problems. Relations and functions: Define a product set; define and apply equivalence relations; construct and apply functions. Apply these concepts to new problems. Natural numbers and induction: Define the natural numbers; apply the principle of induction to verify a selection of properties...

  6. Digital Discretion

    DEFF Research Database (Denmark)

    Busch, Peter Andre; Zinner Henriksen, Helle

    2018-01-01

    discretion is suggested to reduce this footprint by influencing or replacing their discretionary practices using ICT. What is less researched is whether digital discretion can cause changes in public policy outcomes, and under what conditions such changes can occur. Using the concept of public service values......This study reviews 44 peer-reviewed articles on digital discretion published in the period from 1998 to January 2017. Street-level bureaucrats have traditionally had a wide ability to exercise discretion stirring debate since they can add their personal footprint on public policies. Digital......, we suggest that digital discretion can strengthen ethical and democratic values but weaken professional and relational values. Furthermore, we conclude that contextual factors such as considerations made by policy makers on the macro-level and the degree of professionalization of street...

  7. Adolescent social defeat induced alterations in anxious behavior and cognitive flexibility in adult mice: effects of developmental stage and social condition

    Directory of Open Access Journals (Sweden)

    Fang Zhang

    2016-07-01

    Full Text Available Negative social experiences during adolescence increase the risk of psychiatric disorders in adulthood. Using resident-intruder stress, the present study aimed to investigate the effects of adolescent social defeat on emotional and cognitive symptoms associated with psychiatric disorders during adulthood and the effects of the developmental stage and social condition on this process. In experiment 1, animals were exposed to social defeat or manipulation for 10 days during early adolescence (EA, PND 28-37, late adolescence (LA, PND 38-47, and adulthood (ADULT, PND 70-79 and then singly housed until the behavioral tests. Behaviors, including social avoidance of the defeat context and cortically mediated cognitive flexibility in an attentional set-shifting task (AST, were assessed during the week following stress or after 6 weeks during adulthood. We determined that social defeat induced significant and continuous social avoidance across age groups at both time points. The mice that experienced social defeat during adulthood exhibited short-term impairments in reversal learning on the AST that dissipated after 6 weeks. In contrast, social defeat during EA but not LA induced a delayed deficit in extra-dimensional set-shifting in adulthood but not during adolescence. In experiment 2, we further examined the effects of social condition (isolation or social housing after stress on the alterations induced by social defeat during EA in adult mice. The adult mice that had experienced stress during EA exhibited social avoidance similar to the avoidance identified in experiment 1 regardless of the isolation or social housing after the stress. However, social housing after the stress ameliorated the cognitive flexibility deficits induced by early adolescent social defeat in the adult mice, and the social condition had no effect on cognitive function. These findings suggest that the effects of social defeat on emotion and cognitive function are differentially

  8. Chromium (VI Induced Biochemical Changes and Gum Content in Cluster Bean (Cyamopsis tetragonoloba L. at Different Developmental Stages

    Directory of Open Access Journals (Sweden)

    Punesh Sangwan

    2013-01-01

    Full Text Available Chromium (Cr contamination by various industries and other activities is known to inhibit plants growth and development. The present study was conducted using pot experiments in a net house to determine the effect of Cr (VI on biochemical parameters such as photosynthetic pigments, reducing sugars, and important minerals at different stages of growth in leaves, stem, and roots of clusterbean, a multipurpose fodder crop including a source of guar gum. Guar gum content was estimated in seeds at maturity. All biochemical contents showed a great variation with respect to increase in Cr concentration at different stages of growth. The levels of K, Fe, and Zn decreased, while Cr and Na content increased with increase in Cr concentration. Cr induced toxicity in clusterbean appears at 0.5 mg Cr (VI Kg−1 soil with maximum inhibitory effect at 2 mg Cr (VI Kg−1 soil, where impaired sugar supply resulted in decreased guar gum synthesis and altered micronutrient content. The study reveals the possible role of these biochemical parameters in decreasing plant growth and development under heavy metal stress.

  9. Toxicity of road deicing salt (NaCl) and copper (Cu) to fertilization and early developmental stages of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Mahrosh, Urma; Kleiven, Merethe; Meland, Sondre; Rosseland, Bjørn Olav; Salbu, Brit; Teien, Hans-Christian

    2014-09-15

    In many countries, salting of ice or snow covered roads may affect aquatic organisms in the catchment directly or indirectly by mobilization of toxic metals. We studied the toxicity of road deicing salt and copper (Cu) on the vulnerable early life stages of Atlantic salmon (Salmo salar), from fertilization till hatching. Controlled episodic exposure to road salt (≥ 5,000 mg/L) during fertilization resulted in reduced swelling and less percent egg survival. Exposure to Cu both during and post fertilization caused delayed hatching. Larval deformities were, however found as an additional effect, when eggs were exposed to high salt concentration (≥ 5,000 mg/L) mixed with Cu (10 μg Cu/L) during fertilization. Thus, it appears that the sensitivity of early developmental stages of Atlantic salmon increased when exposed to these stressors, and road salt application during spawning can pose threat to Atlantic salmon in water bodies receiving road runoff. The study gives insight on assessment and management of risks on Atlantic salmon population posed by road related hazardous chemicals. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Developmental stages of fish blood flukes, Cardicola forsteri and Cardicola opisthorchis (Trematoda: Aporocotylidae), in their polychaete intermediate hosts collected at Pacific bluefin tuna culture sites in Japan.

    Science.gov (United States)

    Ogawa, Kazuo; Shirakashi, Sho; Tani, Kazuki; Shin, Sang Phil; Ishimaru, Katsuya; Honryo, Tomoki; Sugihara, Yukitaka; Uchida, Hiro'omi

    2017-02-01

    Farming of Pacific bluefin tuna (PBT), Thunnus orientalis, is a rapidly growing industry in Japan. Aporocotylid blood flukes of the genus Cardicola comprising C. orientalis, C. opisthorchis and C. forsteri are parasites of economic importance for PBT farming. Recently, terebellid polychaetes have been identified as the intermediate hosts for all these parasites. We collected infected polychaetes, Terebella sp., the intermediate host of C. opisthorchis, from ropes and floats attached to tuna cages in Tsushima, Nagasaki Prefecture, Japan. Also, Neoamphitrite vigintipes (formerly as Amphitrite sp. sensu Shirakashi et al., 2016), the intermediate host of C. forsteri, were collected from culture cages in Kushimoto, Wakayama Prefecture, Japan. The terebellid intermediate hosts harbored the sporocysts and cercariae in their body cavity. Developmental stages of these blood flukes were molecularly identified using species specific PCR primers. In this paper, we describe the cercaria and sporocyst stages of C. opisthorchis and C. forsteri and compare their morphological characteristics among three Cardicola blood flukes infecting PBT. We also discuss phylogenetic relations of the six genera of the terebellid intermediate hosts (Artacama, Lanassa, Longicarpus, Terebella, Nicolea and Neoamphitrite) of blood flukes infecting marine fishes, based on their morphological characters. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Viability of developmental stages of Schistosoma mansoni quantified with xCELLigence worm real-time motility assay (xWORM

    Directory of Open Access Journals (Sweden)

    Gabriel Rinaldi

    2015-12-01

    Full Text Available Infection with helminth parasites causes morbidity and mortality in billions of people and livestock worldwide. Where anthelmintic drugs are available, drug resistance is a major problem in livestock parasites, and a looming threat to public health. Monitoring the efficacy of these medicines and screening for new drugs has been hindered by the lack of objective, high-throughput approaches. Several cell monitoring technologies have been adapted for parasitic worms, including video-, fluorescence-, metabolism enzyme- and impedance-based tools that minimize the screening bottleneck. Using the xCELLigence impedance-based system we previously developed a motility-viability assay that is applicable for a range of helminth parasites. Here we have improved substantially the assay by using diverse frequency settings, and have named it the xCELLigence worm real-time motility assay (xWORM. By utilizing strictly standardized mean difference analysis we compared the xWORM output measured with 10, 25 and 50 kHz frequencies to quantify the motility of schistosome adults (human blood flukes and hatching of schistosome eggs. Furthermore, we have described a novel application of xWORM to monitor movement of schistosome cercariae, the developmental stage that is infectious to humans. For all three stages, 25 kHz was either optimal or near-optimal for monitoring and quantifying schistosome motility. These improvements in methodology sensitivity should enhance the capacity to screen small compound libraries for new drugs both for schistosomes and other helminth pathogens at large.

  12. Developmental intervals during the larval and juvenile stages of the Antarctic myctophid fish Electrona antarctica in relation to changes in feeding and swimming functions

    Science.gov (United States)

    Moteki, Masato; Tsujimura, Eri; Hulley, Percy-Alexander

    2017-06-01

    The Antarctic myctophid fish species Electrona antarctica is believed to play a key role in the Southern Ocean food web, but there have been few studies on its early life history. This study examined the developmental changes in the external morphology and osteology of E. antarctica from the early larva to juvenile stages through the transformation phase and inferred changes in its behaviour and feeding mode. Once the larvae reached 12-13 mm body length (BL), they adopted a primordial suction feeding mode along with the acquisition of early swimming capabilities. Thereafter, both swimming and feeding functions were enhanced through fin development and ossification and acquisition of elements of the jaw and suspensorium. These processes indicate that larvae transition from the planktonic to nektonic phase upon reaching 12-13 mm BL when they enhance their both swimming and feeding abilities with growth. Transformation occurred when larvae reached 19-21 mm BL with changes such as discontinuous increases in eye diameter and upper jaw length and the appearance of photophores and dense body pigmentation. Osteological development of swimming- and feeding-related structures were mostly complete after transformation. Rapid changes in external morphology and osteology during the transformation stage are most likely related to ontogenetic vertical migration into deep waters.

  13. Radiographic study on the anterior portion of the neck of the condylar process. Aged-related developmental changes based on Hellman's dental stage

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Hiroshi; Yamato, Rieko; Tada, Miwako [Meikai Univ., Sakado, Saitama (Japan). School of Dentistry] [and others

    2003-02-01

    The condylar process is directly and indirectly influenced by the masticatory muscles and the temporomandibular joint, which functions to regulate jaw movement. Age-related changes in the condylar process were found in both external and internal structures. Observation of X-ray profiles afforded identification of areas of interest in the anterior portion of the neck of condylar process. This portion anatomically includes the pterygoid fovea; moreover, the process serves as a terminal for the lateral pterygoid muscle. Rather than directly analyzing bone structure, we made distinct measurements in regions of interest by X-ray image analysis. Subsequently, changes in occlusion during each developmental stage were evaluated. In addition, bone mineral density measurements were performed. Greater growth was recognized in the long axis of the condylar process in comparison to the short axis. The long axis indicated a 2.7-fold increase in ODL (length along the major axis) from the IA period to the VA period; additionally, the total absolute length increased by 3.1-fold. The short axis demonstrated a 2.3-fold increase in ODS (length along the minor axis) from the IA period to the VA period; furthermore, the total average length revealed a 1.9-fold increase. Bone mineral density was highest in the anterior portion (region of interest) and was higher in the posterior portion (cortical bone); than in the middle portion (central bone). Among these 3 areas, density differences became larger as the developmental stage of occlusion progressed. Detailed measurements in the region of interest demonstrated significant increases from the IIC period to the IIIA (B) period, and distinct peak times of increases were observed in bone mineral density: the center bone structure, as well as the posterior cortical bone, showed significant increases between the IIIC period and the IVA period. The anterior border displayed to constant increase with an exception for the period between stages

  14. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2010-01-01

    The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Spring 2010 Ectent: 5 ects Class size: 18......The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Spring 2010 Ectent: 5 ects Class size: 18...

  15. Discrete Mathematics

    DEFF Research Database (Denmark)

    Sørensen, John Aasted

    2010-01-01

    The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Autumn 2010 Ectent: 5 ects Class size: 15......The introduction of the mathematics needed for analysis, design and verification of discrete systems, including applications within programming languages for computer systems. Course sessions and project work. Semester: Autumn 2010 Ectent: 5 ects Class size: 15...

  16. Gas-exchange patterns of Mediterranean fruit fly Pupae (Diptera: Tephritidae): A tool to forecast developmental stage

    International Nuclear Information System (INIS)

    Nestel, D.; Nemny-Lavy, E.; Alchanatis, V.

    2007-01-01

    The pattern of gas-exchange (CO 2 emission) was investigated for developing Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) pupae incubated at different temperatures. This study was undertaken to explore the usefulness of gas-exchange systems in the determination of physiological age in developing pupae that are mass produced for sterile insect technique projects. The rate of CO 2 emission was measured in a closed flow-through system connected to commercial infrared gas analysis equipment. Metabolic activity (rate of CO 2 emission) was related to pupal eye-color, which is the current technique used to determine physiological age. Eye-color was characterized digitally with 3 variables (Hue, Saturation and Intensity), and color separated by discriminant analysis. The rate of CO 2 emission throughout pupal development followed a U-shape, with high levels of emission during pupariation, pupal transformation and final pharate adult stages. Temperature affected the development time of pupae, but not the basic CO 2 emission patterns during development. In all temperatures, rates of CO 2 emission 1 and 2 d before adult emergence were very similar. After mid larval-adult transition (e.g., phanerocephalic pupa), digital eye-color was significantly correlated with CO 2 emission. Results support the suggestion that gas-exchange should be explored further as a system to determine pupal physiological age in mass production of fruit flies. (author) [es

  17. A population of Pax7-expressing muscle progenitor cells show differential responses to muscle injury dependent on developmental stage and injury extent

    Directory of Open Access Journals (Sweden)

    Stefanie eKnappe

    2015-08-01

    Full Text Available Muscle regeneration in vertebrates occurs by the activation of quiescent progenitor cells that express pax7 and replace and repair damaged fibers. We have developed a mechanical injury paradigm in zebrafish to determine whether developmental stage and injury size affect the regeneration dynamics of damaged muscle. We found that both small, focal injuries and large injuries affecting the entire myotome lead to the expression of myf5 and myogenin. Their expression was prolonged in older larvae, indicating a slower process of regeneration. We characterized the endogenous behavior of a population of muscle-resident Pax7-expressing cells using a pax7a:eGFP transgenic line and found that GFP+ cell migration in the myotome dramatically declined between 5 and 7 days post fertilization (dpf. Following a small injury, we observed that GFP+ cells responded by extending processes, before migrating to the injured fibers. Furthermore, these cells responded more rapidly to injury in 4dpf larvae compared to 7dpf. Interestingly, we did not see GFP+ fibers after repair of small injuries, indicating that pax7a-expressing cells did not contribute to fiber formation in this injury context. On the contrary, numerous GFP+ fibers could be observed after a large single myotome injury. Both injury models were accompanied by an increased number of proliferating GFP+ cells, which was more pronounced in larvae injured at 4dpf than 7dpf, This indicates intriguing developmental differences, even at these relatively early ages. Our data also suggests an interesting disparity in the role that pax7a-expressing muscle progenitor cells play during muscle regeneration, which may reflect the extent of muscle damage.

  18. Benih Keturunan Induk Ikan Nila yang Divaksinasi pada Tingkat Kematangan Gonad-2 Lebih Tahan Terhadap Infeksi Streptococcus agalactiae (RESISTANCE OF TILAPIA (OREOCHRIMIS NILOTICUS FRY VACCINATED AT DIFFERENT GONADAL DEVELOPMENTAL STAGES TOWARD STREPTOCO

    Directory of Open Access Journals (Sweden)

    Khairun Nissa

    2016-11-01

    Full Text Available The aim of this study was to evaluate the effectiveness of vaccination based on gonad maturationstages on tilapia brood stocks in which the released antibodies was able to be transferred to the seed.Vaccine composed with whole cells and extracellular product (ECP was injected at stage 2 and stage 3 ofthe gonad development stages at concentration of 109 CFU mL1 as much as 4 mL to 1 kg of brood fish.Control fish was unvaccinated treatment. Challenge study at seed was conducted by immersing S. agalactiaefor 30 minutes at 7, 14, 21, and 28 days post hatching (DPH in 107 CFU/mL. Antibody levels on broodstocks, eggs, and body fluids of seed, and relative percentage survival (RPS of seed post challenge studywere evaluated. The results showed that stage 2 of gonad developmental stages was found on 7 days postinitial spawning and stage 3 found on 14 days post initial spawning of brood fish. Vaccinated done in stage 2 of gonad developmental stages gave immunoglobulin serum in brood (0,166±0,001, egg (0,165±0,002,and seed aged 7, 14, 21, and 28 days post hatching (0,164±0,002, 0,162±0,005, 0,155±0,006, and 0,14±0,008respectively were significantly higher (P<0,05 compared to other treatment. Challenged test that doneby immersing with S. agalactiae suspension on larval aged 7, 14, 21, and 28 days had highest RPS(95,24%, 83,33%, 72,22%, and 56,02% respectively formed on seed from brood stock vaccination in gonaddevelopment stage 2. Vaccination in tilapia brood stocks at stage 2 of gonad developmental stages gavehighest protection by maternal immunity to the seed against S. agalactiae.

  19. Proteomic characterization of larval and adult developmental stages in Echinococcus granulosus reveals novel insight into host-parasite interactions.

    Science.gov (United States)

    Cui, Shu-Jian; Xu, Lei-Lei; Zhang, Ting; Xu, Ming; Yao, Jun; Fang, Cai-Yun; Feng, Zheng; Yang, Peng-Yuan; Hu, Wei; Liu, Feng

    2013-06-12

    Cystic hydatid disease is an important zoonosis caused by Echinococcus granulosus infection. The expression profiles of its parasitic life stages and host-Echinococcus interactions remain to be elucidated. Here, we identified 157 adult and 1588 protoscolex proteins (1610 in all), including 1290 novel identifications. Paramyosins and an antigen B (AgB) were the dominant adult proteins. Dog proteins (30) identified in adults indicated diminished local inflammation caused by adult infection. The protoscolex expresses proteins that have been reported to be antigens in other parasites, such as 6-phosphofructokinase and calcineurin B. Pathway analyses suggested that E. granulosus uses both aerobic and anaerobic carbohydrate metabolisms to generate ATP. E. granulosus expresses proteins involved in synthesis and metabolism of lipids or steroids. At least 339 of 390 sheep proteins identified in protoscolex were novel identifications not seen in previous analyses. IgGs and lambda light chains were the most abundant antibody species. Sheep proteins were enriched for detoxification pathways, implying that host detoxification effects play a central role during host-parasite interactions. Our study provides valuable data on E. granulosus expression characteristics, allowing novel insights into the molecular mechanisms involved in host-parasite interactions. In this study, the Echinococcus granulosus adult worm proteome was analyzed for the first time. The protein identification of E. granulosus protoscoleces was extended dramatically. We also identified the most abundant host proteins co-purified with Echinococcus. The results provide useful information pertaining to the molecular mechanisms behind host-Echinococcus interaction and Echinococcus biology. This data also increases the potential for identifying vaccine candidates and new therapeutic targets, and may aid in the development of protein probes for selective and sensitive diagnosis of echinococcosis infection. In

  20. Characterization of housekeeping genes in zebrafish: male-female differences and effects of tissue type, developmental stage and chemical treatment

    Directory of Open Access Journals (Sweden)

    Callard Gloria V

    2008-11-01

    Full Text Available Abstract Background Research using the zebrafish model has experienced a rapid growth in recent years. Although real-time reverse transcription PCR (QPCR, normalized to an internal reference ("housekeeping" gene, is a frequently used method for quantifying gene expression changes in zebrafish, many commonly used housekeeping genes are known to vary with experimental conditions. To identify housekeeping genes that are stably expressed under different experimental conditions, and thus suitable as normalizers for QPCR in zebrafish, the present study evaluated the expression of eight commonly used housekeeping genes as a function of stage and hormone/toxicant exposure during development, and by tissue type and sex in adult fish. Results QPCR analysis was used to quantify mRNA levels of bactin1, tubulin alpha 1(tuba1, glyceraldehyde-3-phosphate dehydrogenase (gapdh, glucose-6-phosphate dehydrogenase (g6pd, TATA-box binding protein (tbp, beta-2-microglobulin (b2m, elongation factor 1 alpha (elfa, and 18s ribosomal RNA (18s during development (2 – 120 hr postfertilization, hpf; in different tissue types (brain, eye, liver, heart, muscle, gonads of adult males and females; and after treatment of embryos/larvae (24 – 96 hpf with commonly used vehicles for administration and agents that represent known environmental endocrine disruptors. All genes were found to have some degree of variability under the conditions tested here. Rank ordering of expression stability using geNorm analysis identified 18s, b2m, and elfa as most stable during development and across tissue types, while gapdh, tuba1, and tpb were the most variable. Following chemical treatment, tuba1, bactin1, and elfa were the most stably expressed whereas tbp, 18s, and b2m were the least stable. Data also revealed sex differences that are gene- and tissue-specific, and treatment effects that are gene-, vehicle- and ligand-specific. When the accuracy of QPCR analysis was tested using

  1. Nitrogen transporter and assimilation genes exhibit developmental stage-selective expression in maize (Zea mays L.) associated with distinct cis-acting promoter motifs.

    Science.gov (United States)

    Liseron-Monfils, Christophe; Bi, Yong-Mei; Downs, Gregory S; Wu, Wenqing; Signorelli, Tara; Lu, Guangwen; Chen, Xi; Bondo, Eddie; Zhu, Tong; Lukens, Lewis N; Colasanti, Joseph; Rothstein, Steven J; Raizada, Manish N

    2013-10-01

    Nitrogen is considered the most limiting nutrient for maize (Zea mays L.), but there is limited understanding of the regulation of nitrogen-related genes during maize development. An Affymetrix 82K maize array was used to analyze the expression of ≤ 46 unique nitrogen uptake and assimilation probes in 50 maize tissues from seedling emergence to 31 d after pollination. Four nitrogen-related expression clusters were identified in roots and shoots corresponding to, or overlapping, juvenile, adult, and reproductive phases of development. Quantitative real time PCR data was consistent with the existence of these distinct expression clusters. Promoters corresponding to each cluster were screened for over-represented cis-acting elements. The 8-bp distal motif of the Arabidopsis 43-bp nitrogen response element (NRE) was over-represented in nitrogen-related maize gene promoters. This conserved motif, referred to here as NRE43-d8, was previously shown to be critical for nitrate-activated transcription of nitrate reductase (NIA1) and nitrite reductase (NIR1) by the NIN-LIKE PROTEIN 6 (NLP6) in Arabidopsis. Here, NRE43-d8 was over-represented in the promoters of maize nitrate and ammonium transporter genes, specifically those that showed peak expression during early-stage vegetative development. This result predicts an expansion of the NRE-NLP6 regulon and suggests that it may have a developmental component in maize. We also report leaf expression of putative orthologs of nitrite transporters (NiTR1), a transporter not previously reported in maize. We conclude by discussing how each of the four transcriptional modules may be responsible for the different nitrogen uptake and assimilation requirements of leaves and roots at different stages of maize development.

  2. Selection and validation of reference genes for quantitative gene expression analyses in various tissues and seeds at different developmental stages in Bixa orellana L.

    Science.gov (United States)

    Moreira, Viviane S; Soares, Virgínia L F; Silva, Raner J S; Sousa, Aurizangela O; Otoni, Wagner C; Costa, Marcio G C

    2018-05-01

    Bixa orellana L., popularly known as annatto, produces several secondary metabolites of pharmaceutical and industrial interest, including bixin, whose molecular basis of biosynthesis remain to be determined. Gene expression analysis by quantitative real-time PCR (qPCR) is an important tool to advance such knowledge. However, correct interpretation of qPCR data requires the use of suitable reference genes in order to reduce experimental variations. In the present study, we have selected four different candidates for reference genes in B. orellana , coding for 40S ribosomal protein S9 (RPS9), histone H4 (H4), 60S ribosomal protein L38 (RPL38) and 18S ribosomal RNA (18SrRNA). Their expression stabilities in different tissues (e.g. flower buds, flowers, leaves and seeds at different developmental stages) were analyzed using five statistical tools (NormFinder, geNorm, BestKeeper, ΔCt method and RefFinder). The results indicated that RPL38 is the most stable gene in different tissues and stages of seed development and 18SrRNA is the most unstable among the analyzed genes. In order to validate the candidate reference genes, we have analyzed the relative expression of a target gene coding for carotenoid cleavage dioxygenase 1 (CCD1) using the stable RPL38 and the least stable gene, 18SrRNA , for normalization of the qPCR data. The results demonstrated significant differences in the interpretation of the CCD1 gene expression data, depending on the reference gene used, reinforcing the importance of the correct selection of reference genes for normalization.

  3. Discrete mechanics

    CERN Document Server

    Caltagirone, Jean-Paul

    2014-01-01

    This book presents the fundamental principles of mechanics to re-establish the equations of Discrete Mechanics. It introduces physics and thermodynamics associated to the physical modeling.  The development and the complementarity of sciences lead to review today the old concepts that were the basis for the development of continuum mechanics. The differential geometry is used to review the conservation laws of mechanics. For instance, this formalism requires a different location of vector and scalar quantities in space. The equations of Discrete Mechanics form a system of equations where the H

  4. Discrete mechanics

    International Nuclear Information System (INIS)

    Lee, T.D.

    1985-01-01

    This paper reviews the role of time throughout all phases of mechanics: classical mechanics, non-relativistic quantum mechanics, and relativistic quantum theory. As an example of the relativistic quantum field theory, the case of a massless scalar field interacting with an arbitrary external current is discussed. The comparison between the new discrete theory and the usual continuum formalism is presented. An example is given of a two-dimensional random lattice and its duel. The author notes that there is no evidence that the discrete mechanics is more appropriate than the usual continuum mechanics

  5. Effect of electromagnetic field on okra (Hibiscus sculentus L. developmental stages and the effect of okra extract on breast cancer cells

    Directory of Open Access Journals (Sweden)

    Z. Hasani Sadrabadi

    2016-04-01

    Full Text Available Background and objectives: Electric, magnetic and electromagnetic fields can act as stress factors with different effects on biological systems. Due to the nutritional and medicinal values, and the increasing electromagnetic radiations, the present study was performed to investigate the effects of the electromagnetic field on the developmental stages and cytotoxic properties of okra. Methods: Both dry and wet seeds were exposed to electromagnetic field with the intensities of 2 and 4 mT for 60 minutes. MTT assay was applied to evaluate the potential cytotoxic effects of okra extract on MCF-7 cell line. The anatomical structure of leaves in both treated and untreated (control plants were examined. Results: The results showed that a field intensity of 4 mT increased the speed of germination of wet treated seeds and the stem length of dry treated seeds. MTT assay revealed no cytotoxicity of the aqueous extracts of okra pods up to the concentration of 100 μg/mL from either the treated or the control plants towards the MCF-7 cell line. Conclusion: The results suggest that the electromagnetic fields would be able to increase the speed of germination without effects on percentage of germination.

  6. Early nodule senescence is activated in symbiotic mutants of pea (Pisum sativum L.) forming ineffective nodules blocked at different nodule developmental stages.

    Science.gov (United States)

    Serova, Tatiana A; Tsyganova, Anna V; Tsyganov, Viktor E

    2018-04-03

    Plant symbiotic mutants are useful tool to uncover the molecular-genetic mechanisms of nodule senescence. The pea (Pisum sativum L.) mutants SGEFix - -1 (sym40), SGEFix - -3 (sym26), and SGEFix - -7 (sym27) display an early nodule senescence phenotype, whereas the mutant SGEFix - -2 (sym33) does not show premature degradation of symbiotic structures, but its nodules show an enhanced immune response. The nodules of these mutants were compared with each other and with those of the wild-type SGE line using seven marker genes that are known to be activated during nodule senescence. In wild-type SGE nodules, transcript levels of all of the senescence-associated genes were highest at 6 weeks after inoculation (WAI). The senescence-associated genes showed higher transcript abundance in mutant nodules than in wild-type nodules at 2 WAI and attained maximum levels in the mutant nodules at 4 WAI. Immunolocalization analyses showed that the ethylene precursor 1-aminocyclopropane-1-carboxylate accumulated earlier in the mutant nodules than in wild-type nodules. Together, these results showed that nodule senescence was activated in ineffective nodules blocked at different developmental stages in pea lines that harbor mutations in four symbiotic genes.

  7. Effects of Simulated Microgravity on Otolith Growth of Larval Zebrafish using a Rotating-Wall Vessel: Appropriate Rotation Speed and Fish Developmental Stage

    Science.gov (United States)

    Li, Xiaoyan; Anken, Ralf; Liu, Liyue; Wang, Gaohong; Liu, Yongding

    2017-02-01

    Stimulus dependence is a general feature of developing animal sensory systems. In this respect, it has extensively been shown earlier that fish inner ear otoliths can act as test masses as their growth is strongly affected by altered gravity such as hypergravity obtained using centrifuges, by (real) microgravity achieved during spaceflight or by simulated microgravity using a ground-based facility. Since flight opportunities are scarce, ground-based simulators of microgravity, using a wide variety of physical principles, have been developed to overcome this shortcoming. Not all of them, however, are equally well suited to provide functional weightlessness from the perspective of the biosystem under evaluation. Therefore, the range of applicability of a particular simulator has to be extensively tested. Earlier, we have shown that a Rotating-Wall Vessel (RWV) can be used to provide simulated microgravity for developing Zebrafish regarding the effect of rotation on otolith development. In the present study, we wanted to find the most effective speed of rotation and identify the appropriate developmental stage of Zebrafish, where effects are the largest, in order to provide a methodological basis for future in-depth analyses dedicated to the physiological processes underlying otolith growth at altered gravity. Last not least, we compared data on the effect of simulated microgravity on the size versus the weight of otoliths, since the size usually is measured in related studies due to convenience, but the weight more accurately approximates the physical capacity of an otolith. Maintaining embryos at 10 hours post fertilization for three days in the RWV, we found that 15 revolutions per minute (rpm) yielded the strongest effects on otolith growth. Maintenance of Zebrafish staged at 10 hpf, 1 day post fertilization (dpf), 4 dpf, 7 dpf and 14 dpf for three days at 15 rpm resulted in the most prominent effects in 7 dpf larvae. Weighing versus measuring the size of otoliths

  8. Variable Extent of Lineage-Specificity and Developmental Stage-Specificity of Cohesin and CCCTC-Binding Factor Binding Within the Immunoglobulin and T Cell Receptor Loci

    Directory of Open Access Journals (Sweden)

    Salvatore Loguercio

    2018-03-01

    Full Text Available CCCTC-binding factor (CTCF is largely responsible for the 3D architecture of the genome, in concert with the action of cohesin, through the creation of long-range chromatin loops. Cohesin is hypothesized to be the main driver of these long-range chromatin interactions by the process of loop extrusion. Here, we performed ChIP-seq for CTCF and cohesin in two stages each of T and B cell differentiation and examined the binding pattern in all six antigen receptor (AgR loci in these lymphocyte progenitors and in mature T and B cells, ES cells, and fibroblasts. The four large AgR loci have many bound CTCF sites, most of which are only occupied in lymphocytes, while only the CTCF sites at the end of each locus near the enhancers or J genes tend to be bound in non-lymphoid cells also. However, despite the generalized lymphocyte restriction of CTCF binding in AgR loci, the Igκ locus is the only locus that also shows significant lineage-specificity (T vs. B cells and developmental stage-specificity (pre-B vs. pro-B in CTCF binding. We show that cohesin binding shows greater lineage- and stage-specificity than CTCF at most AgR loci, providing more specificity to the loops. We also show that the culture of pro-B cells in IL7, a common practice to expand the number of cells before ChIP-seq, results in a CTCF-binding pattern resembling pre-B cells, as well as other epigenetic and transcriptional characteristics of pre-B cells. Analysis of the orientation of the CTCF sites show that all sites within the large V portions of the Igh and TCRβ loci have the same orientation. This suggests either a lack of requirement for convergent CTCF sites creating loops, or indicates an absence of any loops between CTCF sites within the V region portion of those loci but only loops to the convergent sites at the D-J-enhancer end of each locus. The V region portions of the Igκ and TCRα/δ loci, by contrast, have CTCF sites in both orientations, providing many options for

  9. Reproductive and developmental toxicology

    National Research Council Canada - National Science Library

    Gupta, Ramesh C

    2011-01-01

    .... With a special focus on placental toxicity, this book is the only available reference to connect the three key risk stages, and is the only resource to include reproductive and developmental toxicity in domestic animals, fish, and wildlife.

  10. Solving no-wait two-stage flexible flow shop scheduling problem with unrelated parallel machines and rework time by the adjusted discrete Multi Objective Invasive Weed Optimization and fuzzy dominance approach

    Energy Technology Data Exchange (ETDEWEB)

    Jafarzadeh, Hassan; Moradinasab, Nazanin; Gerami, Ali

    2017-07-01

    Adjusted discrete Multi-Objective Invasive Weed Optimization (DMOIWO) algorithm, which uses fuzzy dominant approach for ordering, has been proposed to solve No-wait two-stage flexible flow shop scheduling problem. Design/methodology/approach: No-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times and probable rework in both stations, different ready times for all jobs and rework times for both stations as well as unrelated parallel machines with regards to the simultaneous minimization of maximum job completion time and average latency functions have been investigated in a multi-objective manner. In this study, the parameter setting has been carried out using Taguchi Method based on the quality indicator for beater performance of the algorithm. Findings: The results of this algorithm have been compared with those of conventional, multi-objective algorithms to show the better performance of the proposed algorithm. The results clearly indicated the greater performance of the proposed algorithm. Originality/value: This study provides an efficient method for solving multi objective no-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times, probable rework in both stations, different ready times for all jobs, rework times for both stations and unrelated parallel machines which are the real constraints.

  11. Solving no-wait two-stage flexible flow shop scheduling problem with unrelated parallel machines and rework time by the adjusted discrete Multi Objective Invasive Weed Optimization and fuzzy dominance approach

    International Nuclear Information System (INIS)

    Jafarzadeh, Hassan; Moradinasab, Nazanin; Gerami, Ali

    2017-01-01

    Adjusted discrete Multi-Objective Invasive Weed Optimization (DMOIWO) algorithm, which uses fuzzy dominant approach for ordering, has been proposed to solve No-wait two-stage flexible flow shop scheduling problem. Design/methodology/approach: No-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times and probable rework in both stations, different ready times for all jobs and rework times for both stations as well as unrelated parallel machines with regards to the simultaneous minimization of maximum job completion time and average latency functions have been investigated in a multi-objective manner. In this study, the parameter setting has been carried out using Taguchi Method based on the quality indicator for beater performance of the algorithm. Findings: The results of this algorithm have been compared with those of conventional, multi-objective algorithms to show the better performance of the proposed algorithm. The results clearly indicated the greater performance of the proposed algorithm. Originality/value: This study provides an efficient method for solving multi objective no-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times, probable rework in both stations, different ready times for all jobs, rework times for both stations and unrelated parallel machines which are the real constraints.

  12. Discrete optimization

    CERN Document Server

    Parker, R Gary

    1988-01-01

    This book treats the fundamental issues and algorithmic strategies emerging as the core of the discipline of discrete optimization in a comprehensive and rigorous fashion. Following an introductory chapter on computational complexity, the basic algorithmic results for the two major models of polynomial algorithms are introduced--models using matroids and linear programming. Further chapters treat the major non-polynomial algorithms: branch-and-bound and cutting planes. The text concludes with a chapter on heuristic algorithms.Several appendixes are included which review the fundamental ideas o

  13. Discrete gradients in discrete classical mechanics

    International Nuclear Information System (INIS)

    Renna, L.

    1987-01-01

    A simple model of discrete classical mechanics is given where, starting from the continuous Hamilton equations, discrete equations of motion are established together with a proper discrete gradient definition. The conservation laws of the total discrete momentum, angular momentum, and energy are demonstrated

  14. Discrete transforms

    CERN Document Server

    Firth, Jean M

    1992-01-01

    The analysis of signals and systems using transform methods is a very important aspect of the examination of processes and problems in an increasingly wide range of applications. Whereas the initial impetus in the development of methods appropriate for handling discrete sets of data occurred mainly in an electrical engineering context (for example in the design of digital filters), the same techniques are in use in such disciplines as cardiology, optics, speech analysis and management, as well as in other branches of science and engineering. This text is aimed at a readership whose mathematical background includes some acquaintance with complex numbers, linear differen­ tial equations, matrix algebra, and series. Specifically, a familiarity with Fourier series (in trigonometric and exponential forms) is assumed, and an exposure to the concept of a continuous integral transform is desirable. Such a background can be expected, for example, on completion of the first year of a science or engineering degree cour...

  15. Biological studies on the tolerance of different developmental stages of the mosquito, Culex Pipiens to gamma radiation through the first five generations

    Energy Technology Data Exchange (ETDEWEB)

    Soliman, I Abul Yazid I

    1993-12-31

    The biological effects of irradiating of the immature stages of Culex Pipiens with chronic doses of gamma radiation in the successive generations were studied. The results obtained a re summarized as follow: A- Egg Irradiation. B- Larval Irradiation. C-Pupal Irradiation. D-Combined effect of irradiation and dimilin on (a) Egg stage. (b) Larval Stage. (c) Pupal Stage. 23 tabs.,19 figs.,86 refs. Thesis (Ms.c)

  16. Discrete Curvatures and Discrete Minimal Surfaces

    KAUST Repository

    Sun, Xiang

    2012-01-01

    This thesis presents an overview of some approaches to compute Gaussian and mean curvature on discrete surfaces and discusses discrete minimal surfaces. The variety of applications of differential geometry in visualization and shape design leads

  17. Discrete Curvatures and Discrete Minimal Surfaces

    KAUST Repository

    Sun, Xiang

    2012-06-01

    This thesis presents an overview of some approaches to compute Gaussian and mean curvature on discrete surfaces and discusses discrete minimal surfaces. The variety of applications of differential geometry in visualization and shape design leads to great interest in studying discrete surfaces. With the rich smooth surface theory in hand, one would hope that this elegant theory can still be applied to the discrete counter part. Such a generalization, however, is not always successful. While discrete surfaces have the advantage of being finite dimensional, thus easier to treat, their geometric properties such as curvatures are not well defined in the classical sense. Furthermore, the powerful calculus tool can hardly be applied. The methods in this thesis, including angular defect formula, cotangent formula, parallel meshes, relative geometry etc. are approaches based on offset meshes or generalized offset meshes. As an important application, we discuss discrete minimal surfaces and discrete Koenigs meshes.

  18. Life Span Developmental Approach

    Directory of Open Access Journals (Sweden)

    Ali Eryilmaz

    2011-03-01

    Full Text Available The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of individuals with respect to developmental stages. This developmental approach suggests that scientific disciplines should not explain developmental facts only with age changes. Along with aging, cognitive, biological, and socioemotional development throughout life should also be considered to provide a reasonable and acceptable context, guideposts, and reasonable expectations for the person. There are three important subjects whom life span developmental approach deals with. These are nature vs nurture, continuity vs discontinuity, and change vs stability. Researchers using life span developmental approach gather and produce knowledge on these three most important domains of individual development with their unique scientific methodology.

  19. Developmentally Appropriate Peace Education Curricula

    Science.gov (United States)

    Lewsader, Joellen; Myers-Walls, Judith A.

    2017-01-01

    Peace education has been offered to children for decades, but those curricula have been only minimally guided by children's developmental stages and needs. In this article, the authors apply their research on children's developmental understanding of peace along with peace education principles and Vygotsky's sociocultural theory to present…

  20. Stages in the development of a model organism as a platform for mechanistic models in developmental biology: Zebrafish, 1970-2000.

    Science.gov (United States)

    Meunier, Robert

    2012-06-01

    Model organisms became an indispensable part of experimental systems in molecular developmental and cell biology, constructed to investigate physiological and pathological processes. They are thought to play a crucial role for the elucidation of gene function, complementing the sequencing of the genomes of humans and other organisms. Accordingly, historians and philosophers paid considerable attention to various issues concerning this aspect of experimental biology. With respect to the representational features of model organisms, that is, their status as models, the main focus was on generalization of phenomena investigated in such experimental systems. Model organisms have been said to be models for other organisms or a higher taxon. This, however, presupposes a representation of the phenomenon in question. I will argue that prior to generalization, model organisms allow researchers to built generative material models of phenomena - structures, processes or the mechanisms that explain them - through their integration in experimental set-ups that carve out the phenomena from the whole organism and thus represent them. I will use the history of zebrafish biology to show how model organism systems, from around 1970 on, were developed to construct material models of molecular mechanisms explaining developmental or physiological processes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Communities of endophytic microorganisms in different developmental stages from a local variety as well as transgenic and conventional isogenic hybrids of maize.

    Science.gov (United States)

    da Silva, Kelly Justin; de Armas, Rafael Dutra; Soares, Cláudio Roberto F S; Ogliari, Juliana Bernardi

    2016-11-01

    The diversity of endophytic microorganisms may change due to the genotype of the host plant and its phenological stage. In this study we evaluated the effect of phenological stage, transgenes and genetic composition of maize on endophytic bacterial and fungal communities. The maize populations were composed of a local variety named Rosado (RS) and three isogenic hybrids. One isogenic hybrid was not genetically modified (NGM). Another hybrid (Hx) contained the transgenes cry1F and pat (T1507 event), which provide resistance to insects of the order Lepidoptera and tolerance to the glufosinate-ammonium herbicide, respectively. The third hybrid (Hxrr) contained the transgene cp4 epsps (NK603 event) combined with the transgenes cry1F and pat (T1507 event), which allow tolerance to the Roundup Ready herbicide, besides the characteristics of Hx. Evaluation of the foliar tissue was done through PCR-DGGE analysis, with specific primers for bacteria and fungi within four phenological stages of maize. The endophytic bacteria were only clustered by phenological stages; the structure of the fungal community was clustered by maize genotypes in each phenological stage. The fungal community from the local variety RS was different from the three hybrids (NGM, Hx and Hxrr) within the four evaluated stages. In the reproductive stage, the fungal community from the two transgenic hybrids (Hx and Hxrr) were separated, and the Hxrr was different from NGM, in the two field experiments. This research study showed that the genetic composition of the maize populations, especially the presence of transgenes, is the determining factor for the changes detected in the endophytic fungal community of maize leaves.

  2. Interferometric measurements of dry mass content in nuclei and cytoplasm in the life cycle of antheridial filaments cells of Chara vulgaris L. in their successive developmental stages

    Directory of Open Access Journals (Sweden)

    Hanna Kuran

    2015-01-01

    Full Text Available Interferometric measurements of the nucleus and cytoplasm dry mass during interphase in the successive stages of development of antheridial filaments of Chara vulgaris demonstrated that the dry mass and surface area of cell nuclei double in size in each of the successive generations of the filaments, whereas neither the surface nor the dry mass of the cytoplasm increase in such proportion in the same period. In the successive stages of development of the antheridial filaments the dry mass and surface area of the nuclei and cytoplasm gradually diminish.

  3. Developmental anatomy of the liver from computerized three-dimensional reconstructions of four human embryos (from Carnegie stage 14 to 23).

    Science.gov (United States)

    Lhuaire, Martin; Tonnelet, Romain; Renard, Yohann; Piardi, Tullio; Sommacale, Daniele; Duparc, Fabrice; Braun, Marc; Labrousse, Marc

    2015-07-01

    Some aspects of human embryogenesis and organogenesis remain unclear, especially concerning the development of the liver and its vasculature. The purpose of this study was to investigate, from a descriptive standpoint, the evolutionary morphogenesis of the human liver and its vasculature by computerized three-dimensional reconstructions of human embryos. Serial histological sections of four human embryos at successive stages of development belonging to three prestigious French historical collections were digitized and reconstructed in 3D using software commonly used in medical radiology. Manual segmentation of the hepatic anatomical regions of interest was performed section by section. In this study, human liver organogenesis was examined at Carnegie stages 14, 18, 21 and 23. Using a descriptive and an analytical method, we showed that these stages correspond to the implementation of the large hepatic vascular patterns (the portal system, the hepatic artery and the hepatic venous system) and the biliary system. To our knowledge, our work is the first descriptive morphological study using 3D computerized reconstructions from serial histological sections of the embryonic development of the human liver between Carnegie stages 14 and 23. Copyright © 2015 Elsevier GmbH. All rights reserved.

  4. Effects of elevated carbon dioxide (CO2) concentrations on early developmental stages of the marine copepod Calanus finmarchicus Gunnerus (Copepoda: Calanoidae).

    Science.gov (United States)

    Pedersen, Sindre Andre; Våge, Vegard Thorset; Olsen, Anders Johny; Hammer, Karen Marie; Altin, Dag

    2014-01-01

    Ocean acidification poses an ongoing threat to marine organisms, and early life stages are believed to be particularly sensitive. The boreal calanoid copepod Calanus finmarchicus seasonally dominates the standing stock of zooplankton in the northern North Sea and North Atlantic, and due to its size and abundance is considered an ecological key species linking energy from primary producers to higher trophic levels. To examine whether the early stages of C. finmarchicus are particularly vulnerable to elevated levels of CO2, eggs and nauplii were subjected to different levels of CO2-acidified seawater for 1 wk. The first experiment, with eggs as the starting point, revealed no marked effect on hatching success, but a significant reduction in nauplii survival during incubation at 8800 ppm CO2. In addition, a significant decrease in ontogenetic development rate during incubation at 8800 ppm CO2 was observed in this experiment. In the second experiment, where third-stage nauplii represented the starting point, no significant effects on ontogenetic development and survival following exposure to pCO2 ≥ 7700 ppm were observed. Data suggest that the two first nauplii stages, which are fed endogenously, may be more vulnerable and therefore likely to represent the "bottleneck" for this species in a more acidic ocean. However, the absence of significant effects in the most sensitive stages during exposure to 2800 ppm CO2, a level that is well above worst-case scenario predictions for year 2300 (approximately 2000 ppm CO2), suggests that this species may be generally robust to direct effects of ocean acidification.

  5. Mimetic discretization methods

    CERN Document Server

    Castillo, Jose E

    2013-01-01

    To help solve physical and engineering problems, mimetic or compatible algebraic discretization methods employ discrete constructs to mimic the continuous identities and theorems found in vector calculus. Mimetic Discretization Methods focuses on the recent mimetic discretization method co-developed by the first author. Based on the Castillo-Grone operators, this simple mimetic discretization method is invariably valid for spatial dimensions no greater than three. The book also presents a numerical method for obtaining corresponding discrete operators that mimic the continuum differential and

  6. Treatment of fish parasites. 11. Morphogenesis of Henneguya laterocapsulata Landsberg, 1987 (Myxosporea, Myxozoa), and the effects of a new triazine derivative, HOE 092 V, on its developmental stages: a light and electron microscopy study.

    Science.gov (United States)

    Schmahl, G; Obiekezie, A; Raether, W

    1993-01-01

    The ultrastructure of sporogenesis was studied in Henneguya laterocapsulata parasitizing the skin of hybrid catfish (Clarias gariepinus x Heterobranchus bidorsalis) in Nigeria. Sporogenesis started when a generative cell was surrounded by a second nondividing cell (i.e., envelope cell). By subsequent divisions of the generative cell, ten cells were produced, which finally became arranged into two spore-producing units. Each unit consisted of a binucleate sporoplasm, two capsulogenic cells, and two valvogenic cells. Apparently capsulogenesis, valvogenesis, and sporoplasm differentiation occurred concomitantly. In research for chemotherapy of fish parasitized by myxosporeans a new triazine derivative, 2-[3,5-alpha-dichloro-4-(4-methyl-sulfonylphenoxy)-phenyl]-1-me thy l- hexahydro-1,2,4-triazine-3,5-dion (HOE 092 V), was tested in vivo against the uni- and multicellular developmental stages of H. laterocapsulata. Naturally infected catfish were incubated in water containing 0, 2.5, 5, and 10 micrograms HOE 092 V/ml or the pure solvent for 3 h. After the fish had been returned into fresh water, they were killed 1 day after the treatment and the plasmodia were studied by means of light and transmission electron microscopy. Starting with a dose of 2.5 micrograms HOE 092 V/ml, the pericyte's outer membrane was broken in the bi- and multicellular stages. The number of ribosomes in the bi- and multicellular stages decreased. In the multicellular stages the rough endoplasmic reticula of the capsulogenic cells were enlarged. Treatment with 5 micrograms HOE 092 V/ml led to breaks in the limiting outer membranes of the capsulogenic cells and to vacuolization of their peripheral cytoplasm. In early prespore stages a decrease in the number of spherical inclusions was recognized.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Time Discretization Techniques

    KAUST Repository

    Gottlieb, S.; Ketcheson, David I.

    2016-01-01

    The time discretization of hyperbolic partial differential equations is typically the evolution of a system of ordinary differential equations obtained by spatial discretization of the original problem. Methods for this time evolution include

  8. Laplacians on discrete and quantum geometries

    International Nuclear Information System (INIS)

    Calcagni, Gianluca; Oriti, Daniele; Thürigen, Johannes

    2013-01-01

    We extend discrete calculus for arbitrary (p-form) fields on embedded lattices to abstract discrete geometries based on combinatorial complexes. We then provide a general definition of discrete Laplacian using both the primal cellular complex and its combinatorial dual. The precise implementation of geometric volume factors is not unique and, comparing the definition with a circumcentric and a barycentric dual, we argue that the latter is, in general, more appropriate because it induces a Laplacian with more desirable properties. We give the expression of the discrete Laplacian in several different sets of geometric variables, suitable for computations in different quantum gravity formalisms. Furthermore, we investigate the possibility of transforming from position to momentum space for scalar fields, thus setting the stage for the calculation of heat kernel and spectral dimension in discrete quantum geometries. (paper)

  9. Sexual dysfunction within an adult developmental perspective.

    Science.gov (United States)

    Fagan, P J; Meyer, J K; Schmidt, C W

    1986-01-01

    The focus of this paper is on the adult who has adequately mastered the oedipal stage of psychosexual development and who presents with a sexual dysfunction. Drawing on the developmental sequence of Erik Erikson, the authors suggest that failure to address adequately an adult psychosocial crisis may result in sexual dysfunction. There may be both adult developmental deficits and regression to adolescent and adult stages previously negotiated. Both may be symptomatically represented by sexual dysfunction. The authors urge that the sexual and marital problems be evaluated within an adult developmental framework and that the therapy address the psychosocial issues which are appropriate to the developmental stage of the patient.

  10. Expression pattern of pluripotent markers in different embryonic developmental stages of buffalo (Bubalus bubalis) embryos and putative embryonic stem cells generated by parthenogenetic activation.

    Science.gov (United States)

    Singh, Karn P; Kaushik, Ramakant; Garg, Veena; Sharma, Ruchi; George, Aman; Singh, Manoj K; Manik, Radhey S; Palta, Prabhat; Singla, Suresh K; Chauhan, Manmohan S

    2012-12-01

    In this study, we describe the production of buffalo parthenogenetic blastocysts and subsequent isolation of parthenogenetic embryonic stem cell (PGESC)-like cells. PGESC colonies exhibited dome-shaped morphology and were clearly distinguishable from the feeder layer cells. Different stages of development of parthenogenetic embryos and derived embryonic stem cell (ESC)-like cells expressed key ESC-specific markers, including OCT-4, NANOG, SOX-2, FOXD3, REX-1, STAT-3, TELOMERASE, NUCLEOSTEMIN, and cMYC. Immunofluorescence-based studies revealed that the PGESCs were positive for surface-based pluripotent markers, viz., SSEA-3, SSEA-4, TRA 1-80, TRA 1-60, CD-9, and CD-90 and exhibited high alkaline phosphatase (ALP) activity. PGEC cell-like cells formed embryoid body (EB)-like structures in hanging drop cultures and when cultured for extended period of time spontaneously differentiated into derivatives of three embryonic germ layers as confirmed by RT-PCR for ectodermal (CYTOKERATIN8, NF-68), mesodermal (MSX1, BMP-4, ASA), and endodermal markers (AFP, HNF-4, GATA-4). Differentiation of PGESCs toward the neuronal lineage was successfully directed by supplementation of serum-containing media with retinoic acid. Our results indicate that the isolated ESC-like cells from parthenogenetic blastocyst hold properties of ESCs and express markers of pluripotency. The pluripotency markers were also expressed by early cleavage-stage of buffalo embryos.

  11. Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs.

    Science.gov (United States)

    Smit, Cornelis H; van Diepen, Angela; Nguyen, D Linh; Wuhrer, Manfred; Hoffmann, Karl F; Deelder, André M; Hokke, Cornelis H

    2015-07-01

    Glycans present on glycoproteins and glycolipids of the major human parasite Schistosoma mansoni induce innate as well as adaptive immune responses in the host. To be able to study the molecular characteristics of schistosome infections it is therefore required to determine the expression profiles of glycans and antigenic glycan-motifs during a range of critical stages of the complex schistosome lifecycle. We performed a longitudinal profiling study covering schistosome glycosylation throughout worm- and egg-development using a mass spectrometry-based glycomics approach. Our study revealed that during worm development N-glycans with Galβ1-4(Fucα1-3)GlcNAc (LeX) and core-xylose motifs were rapidly lost after cercariae to schistosomula transformation, whereas GalNAcβ1-4GlcNAc (LDN)-motifs gradually became abundant and predominated in adult worms. LeX-motifs were present on glycolipids up to 2 weeks of schistosomula development, whereas glycolipids with mono- and multifucosylated LDN-motifs remained present up to the adult worm stage. In contrast, expression of complex O-glycans diminished to undetectable levels within days after transformation. During egg development, a rich diversity of N-glycans with fucosylated motifs was expressed, but with α3-core fucose and a high degree of multifucosylated antennae only in mature eggs and miracidia. N-glycan antennae were exclusively LDN-based in miracidia. O-glycans in the mature eggs were also diverse and contained LeX- and multifucosylated LDN, but none of these were associated with miracidia in which we detected only the Galβ1-3(Galβ1-6)GalNAc core glycan. Immature eggs also exhibited short O-glycan core structures only, suggesting that complex fucosylated O-glycans of schistosome eggs are derived primarily from glycoproteins produced by the subshell envelope in the developed egg. Lipid glycans with multifucosylated GlcNAc repeats were present throughout egg development, but with the longer highly fucosylated

  12. Signaling Pathways Related to Protein Synthesis and Amino Acid Concentration in Pig Skeletal Muscles Depend on the Dietary Protein Level, Genotype and Developmental Stages.

    Science.gov (United States)

    Liu, Yingying; Li, Fengna; Kong, Xiangfeng; Tan, Bie; Li, Yinghui; Duan, Yehui; Blachier, François; Hu, Chien-An A; Yin, Yulong

    2015-01-01

    Muscle growth is regulated by the homeostatic balance of the biosynthesis and degradation of muscle proteins. To elucidate the molecular interactions among diet, pig genotype, and physiological stage, we examined the effect of dietary protein concentration, pig genotype, and physiological stages on amino acid (AA) pools, protein deposition, and related signaling pathways in different types of skeletal muscles. The study used 48 Landrace pigs and 48 pure-bred Bama mini-pigs assigned to each of 2 dietary treatments: lower/GB (Chinese conventional diet)- or higher/NRC (National Research Council)-protein diet. Diets were fed from 5 weeks of age to respective market weights of each genotype. Samples of biceps femoris muscle (BFM, type I) and longissimus dorsi muscle (LDM, type II) were collected at nursery, growing, and finishing phases according to the physiological stage of each genotype, to determine the AA concentrations, mRNA levels for growth-related genes in muscles, and protein abundances of mechanistic target of rapamycin (mTOR) signaling pathway. Our data showed that the concentrations of most AAs in LDM and BFM of pigs increased (Prelated AA, including Met, Phe, Tyr, Pro, and Ser, compared with Landrace pigs. The mRNA levels for myogenic determining factor, myogenin, myocyte-specific enhancer binding factor 2 A, and myostatin of Bama mini-pigs were higher (P<0.05) than those of Landrace pigs, while total and phosphorylated protein levels for protein kinase B, mTOR, and p70 ribosomal protein S6 kinases (p70S6K), and ratios of p-mTOR/mTOR, p-AKT/AKT, and p-p70S6K/p70S6K were lower (P<0.05). There was a significant pig genotype-dependent effect of dietary protein on the levels for mTOR and p70S6K. When compared with the higher protein-NRC diet, the lower protein-GB diet increased (P<0.05) the levels for mTOR and p70S6K in Bama mini-pigs, but repressed (P<0.05) the level for p70S6K in Landrace pigs. The higher protein-NRC diet increased ratio of p-mTOR/mTOR in

  13. Differential gene expression in soybean leaf tissues at late developmental stages under drought stress revealed by genome-wide transcriptome analysis.

    Directory of Open Access Journals (Sweden)

    Dung Tien Le

    Full Text Available The availability of complete genome sequence of soybean has allowed research community to design the 66 K Affymetrix Soybean Array GeneChip for genome-wide expression profiling of soybean. In this study, we carried out microarray analysis of leaf tissues of soybean plants, which were subjected to drought stress from late vegetative V6 and from full bloom reproductive R2 stages. Our data analyses showed that out of 46,093 soybean genes, which were predicted with high confidence among approximately 66,000 putative genes, 41,059 genes could be assigned with a known function. Using the criteria of a ratio change > = 2 and a q-value<0.05, we identified 1458 and 1818 upregulated and 1582 and 1688 downregulated genes in drought-stressed V6 and R2 leaves, respectively. These datasets were classified into 19 most abundant biological categories with similar proportions. There were only 612 and 463 genes that were overlapped among the upregulated and downregulated genes, respectively, in both stages, suggesting that both conserved and unconserved pathways might be involved in regulation of drought response in different stages of plant development. A comparative expression analysis using our datasets and that of drought stressed Arabidopsis leaves revealed the existence of both conserved and species-specific mechanisms that regulate drought responses. Many upregulated genes encode either regulatory proteins, such as transcription factors, including those with high homology to Arabidopsis DREB, NAC, AREB and ZAT/STZ transcription factors, kinases and two-component system members, or functional proteins, e.g. late embryogenesis-abundant proteins, glycosyltransferases, glycoside hydrolases, defensins and glyoxalase I family proteins. A detailed analysis of the GmNAC family and the hormone-related gene category showed that expression of many GmNAC and hormone-related genes was altered by drought in V6 and/or R2 leaves. Additionally, the downregulation of

  14. High environmental ammonia exposure has developmental-stage specific and long-term consequences on the cortisol stress response in zebrafish.

    Science.gov (United States)

    Williams, Tegan A; Bonham, Luke A; Bernier, Nicholas J

    2017-12-01

    The capacity for early life environmental stressors to induce programming effects on the endocrine stress response in fish is largely unknown. In this study we determined the effects of high environmental ammonia (HEA) exposure on the stress response in larval zebrafish, assessed the tolerance of embryonic and larval stages to HEA, and evaluated whether early life HEA exposure has long-term consequences on the cortisol response to a novel stressor. Exposure to 500-2000μM NH 4 Cl for 16h did not affect the gene expression of corticotropin-releasing factor (CRF) system components in 1day post-fertilization (dpf) embryos, but differentially increased crfa, crfb and CRF binding protein (crfbp) expression and stimulated both dose- and time-dependent increases in the whole body cortisol of 5dpf larvae. Pre-acclimation to HEA at 1dpf did not affect the cortisol response to a subsequent NH 4 Cl exposure at 5dpf. In contrast, pre-acclimation to HEA at 5dpf caused a small but significant reduction in the cortisol response to a second NH 4 Cl exposure at 10dpf. While continuous exposure to 500-2000μM NH 4 Cl between 0 and 5dpf had a modest effect on mean survival time, exposure to 400-1000μM NH 4 Cl between 10 and 14dpf decreased mean survival time in a dose-dependent manner. Moreover, pre-acclimation to HEA at 5dpf significantly decreased the risk of mortality to continuous NH 4 Cl exposure between 10 and 14dpf. Finally, while HEA at 1dpf did not affect the cortisol stress response to a novel vortex stressor at 5dpf, the same HEA treatment at 5dpf abolished vortex stressor-induced increases in whole body cortisol at 10 and 60dpf. Together these results show that the impact of HEA on the cortisol stress response during development is life-stage specific and closely linked to ammonia tolerance. Further, we demonstrate that HEA exposure at the larval stage can have persistent effects on the capacity to respond to stressors in later life. Copyright © 2017 Elsevier Inc. All

  15. The Influence of the Plant Growth Regulator Maleic Hydrazide on Egyptian Broomrape Early Developmental Stages and Its Control Efficacy in Tomato under Greenhouse and Field Conditions

    Directory of Open Access Journals (Sweden)

    Ariel Venezian

    2017-05-01

    Full Text Available Broomrapes (Phelipanche spp. and Orobanche spp. are holoparasitic plants that cause tremendous losses of agricultural crops worldwide. Broomrape control is extremely difficult and only amino acid biosynthesis-inhibiting herbicides present an acceptable control level. It is expected that broomrape resistance to these herbicides is not long in coming. Our objective was to develop a broomrape control system in tomato (Solanum lycopersicum L. based on the plant growth regulator maleic hydrazide (MH. Petri-dish and polyethylene-bag system experiments revealed that MH has a slight inhibitory effect on Phelipanche aegyptiaca seed germination but is a potent inhibitor of the first stages of parasitism, namely attachment and the tubercle stage. MH phytotoxicity toward tomato and its P. aegyptiaca-control efficacy were tested in greenhouse experiments. MH was applied at 25, 50, 75, 150, 300, and 600 g a.i. ha-1 to tomato foliage grown in P. aegyptiaca-infested soil at 200 growing degree days (GDD and again at 400 GDD. The treatments had no influence on tomato foliage or root dry weight. The total number of P. aegyptiaca attachments counted on the roots of the treated plants was significantly lower at 75 g a.i. ha-1 and also at higher MH rates. Phelipanche aegyptiaca biomass was close to zero at rates of 150, 300, and 600 g a.i. ha-1 MH. Field experiments were conducted to optimize the rate, timing and number of MH applications. Two application sequences gave superior results, both with five split applications applied at 100, 200, 400, 700, and 1000 GDD: (a constant rate of 400 g a.i. ha-1; (b first two applications at 270 g a.i. ha-1 and the next three applications at 540 g a.i. ha-1. Based on the results of this study, MH was registered for use in Israel in 2013 with the specified protocol and today, it is widely used by most Israeli tomato growers.

  16. Developmental Immunotoxicity

    Science.gov (United States)

    Animal models suggest that the immature immune system is more susceptible to xenobiotics than the fully mature system, and sequelae of developmental immunotoxicant exposure may be persistent well into adulthood. Immune maturation may be delayed by xenobiotic exposure and recover...

  17. Signaling Pathways Related to Protein Synthesis and Amino Acid Concentration in Pig Skeletal Muscles Depend on the Dietary Protein Level, Genotype and Developmental Stages.

    Directory of Open Access Journals (Sweden)

    Yingying Liu

    Full Text Available Muscle growth is regulated by the homeostatic balance of the biosynthesis and degradation of muscle proteins. To elucidate the molecular interactions among diet, pig genotype, and physiological stage, we examined the effect of dietary protein concentration, pig genotype, and physiological stages on amino acid (AA pools, protein deposition, and related signaling pathways in different types of skeletal muscles. The study used 48 Landrace pigs and 48 pure-bred Bama mini-pigs assigned to each of 2 dietary treatments: lower/GB (Chinese conventional diet- or higher/NRC (National Research Council-protein diet. Diets were fed from 5 weeks of age to respective market weights of each genotype. Samples of biceps femoris muscle (BFM, type I and longissimus dorsi muscle (LDM, type II were collected at nursery, growing, and finishing phases according to the physiological stage of each genotype, to determine the AA concentrations, mRNA levels for growth-related genes in muscles, and protein abundances of mechanistic target of rapamycin (mTOR signaling pathway. Our data showed that the concentrations of most AAs in LDM and BFM of pigs increased (P<0.05 gradually with increasing age. Bama mini-pigs had generally higher (P<0.05 muscle concentrations of flavor-related AA, including Met, Phe, Tyr, Pro, and Ser, compared with Landrace pigs. The mRNA levels for myogenic determining factor, myogenin, myocyte-specific enhancer binding factor 2 A, and myostatin of Bama mini-pigs were higher (P<0.05 than those of Landrace pigs, while total and phosphorylated protein levels for protein kinase B, mTOR, and p70 ribosomal protein S6 kinases (p70S6K, and ratios of p-mTOR/mTOR, p-AKT/AKT, and p-p70S6K/p70S6K were lower (P<0.05. There was a significant pig genotype-dependent effect of dietary protein on the levels for mTOR and p70S6K. When compared with the higher protein-NRC diet, the lower protein-GB diet increased (P<0.05 the levels for mTOR and p70S6K in Bama mini-pigs, but

  18. Pm55, a developmental-stage and tissue-specific powdery mildew resistance gene introgressed from Dasypyrum villosum into common wheat.

    Science.gov (United States)

    Zhang, Ruiqi; Sun, Bingxiao; Chen, Juan; Cao, Aizhong; Xing, Liping; Feng, Yigao; Lan, Caixia; Chen, Peidu

    2016-10-01

    Powdery mildew resistance gene Pm55 was physically mapped to chromosome arm 5VS FL 0.60-0.80 of Dasypyrum villosum . Pm55 is present in T5VS·5AL and T5VS·5DL translocations, which should be valuable resources for wheat improvement. Powdery mildew caused by Blumeria graminis f. sp. tritici is a major wheat disease worldwide. Exploiting novel genes effective against powdery mildew from wild relatives of wheat is a promising strategy for controlling this disease. To identify novel resistance genes for powdery mildew from Dasypyrum villosum, a wild wheat relative, we evaluated a set of Chinese Spring-D. villosum disomic addition and whole-arm translocation lines for reactions to powdery mildew. Based on the evaluation data, we concluded that the D. villosum chromosome 5V controls post-seedling resistance to powdery mildew. Subsequently, three introgression lines were developed and confirmed by molecular and cytogenetic analysis following ionizing radiation of the pollen of a Chinese Spring-D. villosum 5V disomic addition line. A homozygous T5VS·5AL translocation line (NAU421) with good plant vigor and full fertility was further characterized using sequential genomic in situ hybridization, C-banding, and EST-STS marker analysis. A dominant gene permanently named Pm55 was located in chromosome bin 5VS 0.60-0.80 based on the responses to powdery mildew of all wheat-D. villosum 5V introgression lines evaluated at both seeding and adult stages. This study demonstrated that Pm55 conferred growth-stage and tissue-specific dependent resistance; therefore, it provides a novel resistance type for powdery mildew. The T5VS·5AL translocation line with additional softness loci Dina/Dinb of D. villosum provides a possibility of extending the range of grain textures to a super-soft category. Accordingly, this stock is a new source of resistance to powdery mildew and may be useful in both resistance mechanism studies and soft wheat improvement.

  19. The status of Demodex cornei: description of the species and developmental stages, and data on demodecid mites in the domestic dog Canis lupus familiaris.

    Science.gov (United States)

    Izdebska, J N; Rolbiecki, L

    2018-03-30

    Demodecosis canina is one of the most important dog parasitoses, but its aetiology is still not well known. There are currently two known species of demodecid mite specific to the domestic dog Canis lupus familiaris Linnaeus, 1758 (Carnivora: Canidae). These are Demodex canis Leydig, 1859 (Acariformes: Demodecidae) and Demodex injai Desch & Hillier, 2003. There have also been many reports of the so-called 'short form', considered to be a separate species functioning under the name Demodex cornei nomen nudum, for which, however, no formal valid description has been documented. Taxonomic analysis of short forms of dog demodecid mites, associated with the stratum corneum, was performed, in line with the taxonomic criteria of Demodecidae systematics. This form was found to be a distinct species with features that differ from those of the other known species of this family. The species, including the adult and immature stages, is described. It is likely that different Demodex species parasitizing the domestic dog may be responsible for differentiated symptoms and different courses of demodecosis. However, the basis for clarifying this issue should be the correct, unambiguous identification of the species causing parasitosis. © 2018 The Royal Entomological Society.

  20. Effects of methoprene, a juvenile hormone analog, on survival of various developmental stages, adult emergence, reproduction and behavior of Asian citrus psyllid, Diaphorina citri Kuwayama.

    Science.gov (United States)

    Brar, Gurpreet S; Meyer, Wendy; Stelinski, Lukasz L

    2015-12-01

    The Asian citrus citrus psyllid, Diaphorina citri Kuwayama, transmits a bacterium that causes huanglongbing in citrus. Frequent and repeated use of neurotoxic insecticides against D. citri has resulted in the development of insecticide resistance. We evaluated the effects of the juvenile hormone analog methoprene on egg hatch, nymphal development, adult emergence, reproduction and behavior of D. citri. Methoprene significantly reduced the viability of eggs that were between 0 and 4 days old. Egg hatch of 0-48-h-old and 49-96-h-old eggs was 8 and 9%, respectively, when treated with 320 µg mL(-1) of methoprene. Methoprene caused significant mortality of first-, third- and fifth-instar D. citri nymphs and reduced adult emergence as compared with controls. Methoprene caused less than 5% adult emergence when first- and third-instar stages were treated, respectively, and less than 40% adult emergence when fifth instars were treated. Reduced fertility of females was observed when they emerged from methoprene-treated fifth instars. Methoprene was effective in reducing egg hatch, suppressing nymphal development and decreasing adult emergence of D. citri under laboratory conditions. Treatment of fifth instars reduced the fertility of females. Methoprene might be a possible tool for integrated management of D. citri. © 2015 Society of Chemical Industry.

  1. Antimicrobial Tolerance of Pseudomonas aeruginosa Biofilms Is Activated during an Early Developmental Stage and Requires the Two-Component Hybrid SagS

    Science.gov (United States)

    Gupta, Kajal; Marques, Cláudia N. H.; Petrova, Olga E.

    2013-01-01

    A hallmark characteristic of biofilms is their extraordinary tolerance to antimicrobial agents. While multiple factors are thought to contribute to the high level of antimicrobial tolerance of biofilms, little is known about the timing of induction of biofilm tolerance. Here, we asked when over the course of their development do biofilms gain their tolerance to antimicrobial agents? We demonstrate that in Pseudomonas aeruginosa, biofilm tolerance is linked to biofilm development, with transition to the irreversible attachment stage regulated by the two-component hybrid SagS, marking the timing when biofilms switch to the high-level tolerance phenotype. Inactivation of sagS rendered biofilms but not planktonic cells more susceptible to tobramycin, norfloxacin, and hydrogen peroxide. Moreover, inactivation of sagS also eliminated the recalcitrance of biofilms to killing by bactericidal antimicrobial agents, a phenotype comparable to that observed upon inactivation of brlR, which encodes a MerR-like transcriptional regulator required for biofilm tolerance. Multicopy expression of brlR in a ΔsagS mutant restored biofilm resistance and recalcitrance to killing by bactericidal antibiotics to wild-type levels. In contrast, expression of sagS did not restore the susceptibility phenotype of ΔbrlR mutant biofilms to wild-type levels, indicating that BrlR functions downstream of SagS. Inactivation of sagS correlated with reduced BrlR levels in biofilms, with the produced BrlR being impaired in binding to the previously described BrlR-activated promoters of the two multidrug efflux pump operons mexAB-oprM and mexEF-oprN. Our findings demonstrate that biofilm tolerance is linked to early biofilm development and SagS, with SagS contributing indirectly to BrlR activation. PMID:23995639

  2. 生物炭对杉木人工林土壤氮素的影响%Effect of applying biochar plantations of Chinese fir soil nitrogen in different developmental stages

    Institute of Scientific and Technical Information of China (English)

    魏志超; 孟李群; 李惠通; 贾代东; 刘爱琴

    2017-01-01

    Biochar, as a good sequestration agent, is also a new material for improving soil physical and chemical properties. Chinese fir plantation, at different developmental stage in Xinkou teaching state forest farm of Fujian Sanming, were studied to explore the effects of different types of biochar on soil nitrogen forms. Two different kinds of biochar ( wood-biochar, bamboo-bio-char) were choosed to find the influence of different type of biochar on soil fertility in the Chinese fir plantation. The results showed as follows:the biochar had little effect on soil total nitrogen on the surface in the 1st year. Biochar treatment had significantly increased soil hydrolysis nitrogen in the 1st year, then decreased in the 2nd year, and there was no significant difference compared to the control in the 3rd year. Two types of biochar had little influenced on inorganic nitrogen in the soil, bamboo-biochar treatment increased, but the woody-biochar treatment decreased mostly. There were significant interactive effects among biochar treatment, developmental stage and soil layer on the soil hydrolysis nitrogen. The influence of biochar on different developmental Chinese fir stages follow by:youth stand> middle stand> mature stand. Two types of biochar comparison showed that, bamboo-biochar is better than wood-biochar on soil improvement.%为探讨不同类型生物炭对杉木人工林土壤氮素形态的影响,以福建省三明市莘口教学林场不同发育阶段杉木人工林为研究对象,选择2种不同类型生物炭(竹炭和木炭),研究其对杉木人工林土壤不同形态氮素的影响。结果表明:2种生物炭对土壤全氮含量影响较小且主要集中于表层,施炭处理1a后,土壤水解氮含量均有显著提高,但从第2年开始水解氮含量逐渐下降,在第3年水解氮含量与对照无显著差异;2种生物炭对土壤无机态氮含量影响差异较小,竹炭处理的土壤无机氮含量有所增加,而木炭

  3. Toward a Neuroscience of Adult Cognitive Developmental Theory

    Directory of Open Access Journals (Sweden)

    Fady Girgis

    2018-01-01

    with psychological tasks that test these models. In addition, we will review computational modeling approaches to cognitive development, and show how mathematical modeling can provide insights into how sometimes continuous changes in the neural processing substrate can give rise to relatively discrete developmental stages. Because deficiencies in adult cognitive development can result in disorders such as autism and depression, bridging the gaps between developmental psychology, neuroscience, and modeling has potential implications for clinical practice. As neuromodulation techniques such as deep brain and transcranial stimulation continue to advance, interfacing with these systems may lead to the emergence of novel investigational methods and therapeutic strategies in adults suffering from developmental disorders.

  4. Toward a Neuroscience of Adult Cognitive Developmental Theory.

    Science.gov (United States)

    Girgis, Fady; Lee, Darrin J; Goodarzi, Amir; Ditterich, Jochen

    2018-01-01

    test these models. In addition, we will review computational modeling approaches to cognitive development, and show how mathematical modeling can provide insights into how sometimes continuous changes in the neural processing substrate can give rise to relatively discrete developmental stages. Because deficiencies in adult cognitive development can result in disorders such as autism and depression, bridging the gaps between developmental psychology, neuroscience, and modeling has potential implications for clinical practice. As neuromodulation techniques such as deep brain and transcranial stimulation continue to advance, interfacing with these systems may lead to the emergence of novel investigational methods and therapeutic strategies in adults suffering from developmental disorders.

  5. Water deficiency at different developmental stages of Glycine max can improve drought tolerance Deficiência hídrica em diferentes estágios de desenvolvimento de soja pode aumentar a tolerância à seca

    Directory of Open Access Journals (Sweden)

    Alan Panaia Kron

    2008-01-01

    Full Text Available Developmental windows are specific periods of sensitivity during normal plant development in which a perturbation may be adaptively integrated. In these periods, sub-lethal environmental perturbations may improve the capacity to grow at lethal conditions. The aim of this study was to test the hypothesis that previous non-lethal water deficit applied in different developmental stages in soybean plants could enables them to improve the tolerance to environmental perturbations. In order to test this hypothesis we carried out an experiment with soybean plants submitted to water deficit in different stages of plant development, evaluating yield and physiological aspects. Our results indicated that water deficit experienced on V4 stage (vegetative induces more suitable response, enabling plants to develop a process of tolerance improvement to a further water shortage period, probably through a reduction of growth, which maintains a conservative strategy of energy use. On the other hand, water deficit in R1 stage (reproductive, increased the plant susceptibility to posterior water withholding. This " strategy" was the opposite of the one employed by plants on V4 stage, i.e., to maintain growth rate probably at the expense of a higher energetic cost.Janelas de desenvolvimento são períodos específicos durante o ciclo de vida das plantas em que uma perturbação ambiental pode ser incorporada através de um processo de adaptação. Nesses períodos, perturbações ambientais subletais podem capacitar as plantas a crescer em condições letais. O objetivo deste trabalho foi testar a hipótese de que plantas de soja (Glycine max submetidas à deficiência hídrica não-letal em diferentes estágios de seu desenvolvimento poderiam otimizar sua tolerância a estresses ambientais posteriores. Para testar essa hipótese, foi conduzido um experimento com plantas de soja submetidas à deficiência hídrica em diferentes estágios de desenvolvimento, avaliando

  6. Microarrays for global expression constructed with a low redundancy set of 27,500 sequenced cDNAs representing an array of developmental stages and physiological conditions of the soybean plant

    Directory of Open Access Journals (Sweden)

    Retzel Ernest

    2004-09-01

    Full Text Available Abstract Background Microarrays are an important tool with which to examine coordinated gene expression. Soybean (Glycine max is one of the most economically valuable crop species in the world food supply. In order to accelerate both gene discovery as well as hypothesis-driven research in soybean, global expression resources needed to be developed. The applications of microarray for determining patterns of expression in different tissues or during conditional treatments by dual labeling of the mRNAs are unlimited. In addition, discovery of the molecular basis of traits through examination of naturally occurring variation in hundreds of mutant lines could be enhanced by the construction and use of soybean cDNA microarrays. Results We report the construction and analysis of a low redundancy 'unigene' set of 27,513 clones that represent a variety of soybean cDNA libraries made from a wide array of source tissue and organ systems, developmental stages, and stress or pathogen-challenged plants. The set was assembled from the 5' sequence data of the cDNA clones using cluster analysis programs. The selected clones were then physically reracked and sequenced at the 3' end. In order to increase gene discovery from immature cotyledon libraries that contain abundant mRNAs representing storage protein gene families, we utilized a high density filter normalization approach to preferentially select more weakly expressed cDNAs. All 27,513 cDNA inserts were amplified by polymerase chain reaction. The amplified products, along with some repetitively spotted control or 'choice' clones, were used to produce three 9,728-element microarrays that have been used to examine tissue specific gene expression and global expression in mutant isolines. Conclusions Global expression studies will be greatly aided by the availability of the sequence-validated and low redundancy cDNA sets described in this report. These cDNAs and ESTs represent a wide array of developmental

  7. Developmental Scaffolding

    DEFF Research Database (Denmark)

    Giorgi, Franco; Bruni, Luis Emilio

    2015-01-01

    . Within the developmental hierarchy, each module yields an inter-level relationship that makes it possible for the scaffolding to mediate the production of selectable variations. Awide range of genetic, cellular and morphological mechanisms allows the scaffolding to integrate these modular variations...... to the complexity of sign recognition proper of a cellular community. In this semiotic perspective, the apparent goal directness of any developmental strategy should no longer be accounted for by a predetermined genetic program, but by the gradual definition of the relationships selected amongst the ones...

  8. Baecklund transformations for discrete Painleve equations: Discrete PII-PV

    International Nuclear Information System (INIS)

    Sakka, A.; Mugan, U.

    2006-01-01

    Transformation properties of discrete Painleve equations are investigated by using an algorithmic method. This method yields explicit transformations which relates the solutions of discrete Painleve equations, discrete P II -P V , with different values of parameters. The particular solutions which are expressible in terms of the discrete analogue of the classical special functions of discrete Painleve equations can also be obtained from these transformations

  9. Discrete Gabor transform and discrete Zak transform

    NARCIS (Netherlands)

    Bastiaans, M.J.; Namazi, N.M.; Matthews, K.

    1996-01-01

    Gabor's expansion of a discrete-time signal into a set of shifted and modulated versions of an elementary signal or synthesis window is introduced, along with the inverse operation, i.e. the Gabor transform, which uses an analysis window that is related to the synthesis window and with the help of

  10. Discrete Mathematics Re "Tooled."

    Science.gov (United States)

    Grassl, Richard M.; Mingus, Tabitha T. Y.

    1999-01-01

    Indicates the importance of teaching discrete mathematics. Describes how the use of technology can enhance the teaching and learning of discrete mathematics. Explorations using Excel, Derive, and the TI-92 proved how preservice and inservice teachers experienced a new dimension in problem solving and discovery. (ASK)

  11. Developmental delay

    Science.gov (United States)

    Nutrition support is essential for the care of the child with developmental delay. After a thorough evaluation, an individualized intervention plan that accounts for the child’s nutrition status, feeding ability, and medical condition may be determined. Nutrition assessments may be performed at leas...

  12. Developmental Work

    DEFF Research Database (Denmark)

    Møller, Niels; Hvid, Helge; Kristensen, Tage Søndergaard

    2003-01-01

    Human Deveoplment and Working Life - Work for Welfare explores whether the development of human resources at company level can improve individuals' quality of life, companies' possibilities of development, and welfare and democracy in society. Chapter two discuss the concept "developmental work...

  13. Homogenization of discrete media

    International Nuclear Information System (INIS)

    Pradel, F.; Sab, K.

    1998-01-01

    Material such as granular media, beam assembly are easily seen as discrete media. They look like geometrical points linked together thanks to energetic expressions. Our purpose is to extend discrete kinematics to the one of an equivalent continuous material. First we explain how we build the localisation tool for periodic materials according to estimated continuum medium type (classical Cauchy, and Cosserat media). Once the bridge built between discrete and continuum media, we exhibit its application over two bidimensional beam assembly structures : the honey comb and a structural reinforced variation. The new behavior is then applied for the simple plan shear problem in a Cosserat continuum and compared with the real discrete solution. By the mean of this example, we establish the agreement of our new model with real structures. The exposed method has a longer range than mechanics and can be applied to every discrete problems like electromagnetism in which relationship between geometrical points can be summed up by an energetic function. (orig.)

  14. Discrete density of states

    International Nuclear Information System (INIS)

    Aydin, Alhun; Sisman, Altug

    2016-01-01

    By considering the quantum-mechanically minimum allowable energy interval, we exactly count number of states (NOS) and introduce discrete density of states (DOS) concept for a particle in a box for various dimensions. Expressions for bounded and unbounded continua are analytically recovered from discrete ones. Even though substantial fluctuations prevail in discrete DOS, they're almost completely flattened out after summation or integration operation. It's seen that relative errors of analytical expressions of bounded/unbounded continua rapidly decrease for high NOS values (weak confinement or high energy conditions), while the proposed analytical expressions based on Weyl's conjecture always preserve their lower error characteristic. - Highlights: • Discrete density of states considering minimum energy difference is proposed. • Analytical DOS and NOS formulas based on Weyl conjecture are given. • Discrete DOS and NOS functions are examined for various dimensions. • Relative errors of analytical formulas are much better than the conventional ones.

  15. Discrete density of states

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Alhun; Sisman, Altug, E-mail: sismanal@itu.edu.tr

    2016-03-22

    By considering the quantum-mechanically minimum allowable energy interval, we exactly count number of states (NOS) and introduce discrete density of states (DOS) concept for a particle in a box for various dimensions. Expressions for bounded and unbounded continua are analytically recovered from discrete ones. Even though substantial fluctuations prevail in discrete DOS, they're almost completely flattened out after summation or integration operation. It's seen that relative errors of analytical expressions of bounded/unbounded continua rapidly decrease for high NOS values (weak confinement or high energy conditions), while the proposed analytical expressions based on Weyl's conjecture always preserve their lower error characteristic. - Highlights: • Discrete density of states considering minimum energy difference is proposed. • Analytical DOS and NOS formulas based on Weyl conjecture are given. • Discrete DOS and NOS functions are examined for various dimensions. • Relative errors of analytical formulas are much better than the conventional ones.

  16. Discrete control systems

    CERN Document Server

    Okuyama, Yoshifumi

    2014-01-01

    Discrete Control Systems establishes a basis for the analysis and design of discretized/quantized control systemsfor continuous physical systems. Beginning with the necessary mathematical foundations and system-model descriptions, the text moves on to derive a robust stability condition. To keep a practical perspective on the uncertain physical systems considered, most of the methods treated are carried out in the frequency domain. As part of the design procedure, modified Nyquist–Hall and Nichols diagrams are presented and discretized proportional–integral–derivative control schemes are reconsidered. Schemes for model-reference feedback and discrete-type observers are proposed. Although single-loop feedback systems form the core of the text, some consideration is given to multiple loops and nonlinearities. The robust control performance and stability of interval systems (with multiple uncertainties) are outlined. Finally, the monograph describes the relationship between feedback-control and discrete ev...

  17. Discrete repulsive oscillator wavefunctions

    International Nuclear Information System (INIS)

    Munoz, Carlos A; Rueda-Paz, Juvenal; Wolf, Kurt Bernardo

    2009-01-01

    For the study of infinite discrete systems on phase space, the three-dimensional Lorentz algebra and group, so(2,1) and SO(2,1), provide a discrete model of the repulsive oscillator. Its eigenfunctions are found in the principal irreducible representation series, where the compact generator-that we identify with the position operator-has the infinite discrete spectrum of the integers Z, while the spectrum of energies is a double continuum. The right- and left-moving wavefunctions are given by hypergeometric functions that form a Dirac basis for l 2 (Z). Under contraction, the discrete system limits to the well-known quantum repulsive oscillator. Numerical computations of finite approximations raise further questions on the use of Dirac bases for infinite discrete systems.

  18. Discrete Element Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Morris, J; Johnson, S

    2007-12-03

    The Distinct Element Method (also frequently referred to as the Discrete Element Method) (DEM) is a Lagrangian numerical technique where the computational domain consists of discrete solid elements which interact via compliant contacts. This can be contrasted with Finite Element Methods where the computational domain is assumed to represent a continuum (although many modern implementations of the FEM can accommodate some Distinct Element capabilities). Often the terms Discrete Element Method and Distinct Element Method are used interchangeably in the literature, although Cundall and Hart (1992) suggested that Discrete Element Methods should be a more inclusive term covering Distinct Element Methods, Displacement Discontinuity Analysis and Modal Methods. In this work, DEM specifically refers to the Distinct Element Method, where the discrete elements interact via compliant contacts, in contrast with Displacement Discontinuity Analysis where the contacts are rigid and all compliance is taken up by the adjacent intact material.

  19. Identification of parameters of discrete-continuous models

    International Nuclear Information System (INIS)

    Cekus, Dawid; Warys, Pawel

    2015-01-01

    In the paper, the parameters of a discrete-continuous model have been identified on the basis of experimental investigations and formulation of optimization problem. The discrete-continuous model represents a cantilever stepped Timoshenko beam. The mathematical model has been formulated and solved according to the Lagrange multiplier formalism. Optimization has been based on the genetic algorithm. The presented proceeding’s stages make the identification of any parameters of discrete-continuous systems possible

  20. Identification of parameters of discrete-continuous models

    Energy Technology Data Exchange (ETDEWEB)

    Cekus, Dawid, E-mail: cekus@imipkm.pcz.pl; Warys, Pawel, E-mail: warys@imipkm.pcz.pl [Institute of Mechanics and Machine Design Foundations, Czestochowa University of Technology, Dabrowskiego 73, 42-201 Czestochowa (Poland)

    2015-03-10

    In the paper, the parameters of a discrete-continuous model have been identified on the basis of experimental investigations and formulation of optimization problem. The discrete-continuous model represents a cantilever stepped Timoshenko beam. The mathematical model has been formulated and solved according to the Lagrange multiplier formalism. Optimization has been based on the genetic algorithm. The presented proceeding’s stages make the identification of any parameters of discrete-continuous systems possible.

  1. Discrete Calculus by Analogy

    CERN Document Server

    Izadi, F A; Bagirov, G

    2009-01-01

    With its origins stretching back several centuries, discrete calculus is now an increasingly central methodology for many problems related to discrete systems and algorithms. The topics covered here usually arise in many branches of science and technology, especially in discrete mathematics, numerical analysis, statistics and probability theory as well as in electrical engineering, but our viewpoint here is that these topics belong to a much more general realm of mathematics; namely calculus and differential equations because of the remarkable analogy of the subject to this branch of mathemati

  2. Discrete modeling considerations in multiphase fluid dynamics

    International Nuclear Information System (INIS)

    Ransom, V.H.; Ramshaw, J.D.

    1988-01-01

    The modeling of multiphase flows play a fundamental role in light water reactor safety. The main ingredients in our discrete modeling Weltanschauung are the following considerations: (1) Any physical model must be cast into discrete form for a digital computer. (2) The usual approach of formulating models in differential form and then discretizing them is potentially hazardous. It may be preferable to formulate the model in discrete terms from the outset. (3) Computer time and storage constraints limit the resolution that can be employed in practical calculations. These limits effectively define the physical phenomena, length scales, and time scales which cannot be directly represented in the calculation and therefore must be modeled. This information should be injected into the model formulation process at an early stage. (4) Practical resolution limits are generally so coarse that traditional convergence and truncation-error analyses become irrelevant. (5) A discrete model constitutes a reduced description of a physical system, from which fine-scale details are eliminated. This elimination creates a statistical closure problem. Methods from statistical physics may therefore be useful in the formulation of discrete models. In the present paper we elaborate on these themes and illustrate them with simple examples. 48 refs

  3. Developmental immunotoxicology of lead

    International Nuclear Information System (INIS)

    Dietert, Rodney R.; Lee, Ji-Eun; Hussain, Irshad; Piepenbrink, Michael

    2004-01-01

    The heavy metal, lead, is a known developmental immunotoxicant that has been shown to produce immune alterations in humans as well as other species. Unlike many compounds that exert adverse immune effects, lead exposure at low to moderate levels does not produce widespread loss of immune cells. In contrast, changes resulting from lead exposure are subtle at the immune cell population level but, nevertheless, can be functionally dramatic. A hallmark of lead-induced immunotoxicity is a pronounced shift in the balance in T helper cell function toward T helper 2 responses at the expense of T helper 1 functions. This bias alters the nature and range of immune responses that can be produced thereby influencing host susceptibility to various diseases. Immunotoxic responses to lead appear to differ across life stages not only quantitatively with regard to dose response, but also qualitatively in terms of the spectrum of immune alterations. Experimental studies in several lab animal species suggest the latter stages of gestation are a period of considerable sensitivity for lead-induced immunotoxicity. This review describes the basic characteristics of lead-induced immunotoxicity emphasizing experimental animal results. It also provides a framework for the consideration of toxicant exposure effects across life stages. The existence of and probable basis for developmental windows of immune hyper-susceptibility are presented. Finally, the potential for lead to serve as a perinatal risk factor for childhood asthma as well as other diseases is considered

  4. Finite Discrete Gabor Analysis

    DEFF Research Database (Denmark)

    Søndergaard, Peter Lempel

    2007-01-01

    frequency bands at certain times. Gabor theory can be formulated for both functions on the real line and for discrete signals of finite length. The two theories are largely the same because many aspects come from the same underlying theory of locally compact Abelian groups. The two types of Gabor systems...... can also be related by sampling and periodization. This thesis extends on this theory by showing new results for window construction. It also provides a discussion of the problems associated to discrete Gabor bases. The sampling and periodization connection is handy because it allows Gabor systems...... on the real line to be well approximated by finite and discrete Gabor frames. This method of approximation is especially attractive because efficient numerical methods exists for doing computations with finite, discrete Gabor systems. This thesis presents new algorithms for the efficient computation of finite...

  5. Adaptive Discrete Hypergraph Matching.

    Science.gov (United States)

    Yan, Junchi; Li, Changsheng; Li, Yin; Cao, Guitao

    2018-02-01

    This paper addresses the problem of hypergraph matching using higher-order affinity information. We propose a solver that iteratively updates the solution in the discrete domain by linear assignment approximation. The proposed method is guaranteed to converge to a stationary discrete solution and avoids the annealing procedure and ad-hoc post binarization step that are required in several previous methods. Specifically, we start with a simple iterative discrete gradient assignment solver. This solver can be trapped in an -circle sequence under moderate conditions, where is the order of the graph matching problem. We then devise an adaptive relaxation mechanism to jump out this degenerating case and show that the resulting new path will converge to a fixed solution in the discrete domain. The proposed method is tested on both synthetic and real-world benchmarks. The experimental results corroborate the efficacy of our method.

  6. Discrete fractional calculus

    CERN Document Server

    Goodrich, Christopher

    2015-01-01

    This text provides the first comprehensive treatment of the discrete fractional calculus. Experienced researchers will find the text useful as a reference for discrete fractional calculus and topics of current interest. Students who are interested in learning about discrete fractional calculus will find this text to provide a useful starting point. Several exercises are offered at the end of each chapter and select answers have been provided at the end of the book. The presentation of the content is designed to give ample flexibility for potential use in a myriad of courses and for independent study. The novel approach taken by the authors includes a simultaneous treatment of the fractional- and integer-order difference calculus (on a variety of time scales, including both the usual forward and backwards difference operators). The reader will acquire a solid foundation in the classical topics of the discrete calculus while being introduced to exciting recent developments, bringing them to the frontiers of the...

  7. Discrete quantum gravity

    International Nuclear Information System (INIS)

    Williams, Ruth M

    2006-01-01

    A review is given of a number of approaches to discrete quantum gravity, with a restriction to those likely to be relevant in four dimensions. This paper is dedicated to Rafael Sorkin on the occasion of his sixtieth birthday

  8. Discrete computational structures

    CERN Document Server

    Korfhage, Robert R

    1974-01-01

    Discrete Computational Structures describes discrete mathematical concepts that are important to computing, covering necessary mathematical fundamentals, computer representation of sets, graph theory, storage minimization, and bandwidth. The book also explains conceptual framework (Gorn trees, searching, subroutines) and directed graphs (flowcharts, critical paths, information network). The text discusses algebra particularly as it applies to concentrates on semigroups, groups, lattices, propositional calculus, including a new tabular method of Boolean function minimization. The text emphasize

  9. Exposure of BALB/c mice to diesel engine exhaust origin secondary organic aer-osol (DE-SOA during the developmental stages impairs the social behavior in adult life of the males

    Directory of Open Access Journals (Sweden)

    Tin-Tin eWin-Shwe

    2016-01-01

    Full Text Available Secondary organic aerosol (SOA is a component of particulate matter (PM 2.5 and formed in the atmosphere by oxidation of volatile organic compounds. Recently, we have reported that inhalation exposure to diesel engine exhaust (DE originated SOA (DE-SOA affect novel object recognition ability and impair maternal behavior in adult mice. However, it is not clear whether early life exposure to SOA during the de-velopmental stages affect social behavior in adult life or not. In the present study, to investigate the effects of early life exposure to DE-SOA during the gestational and lactation stages on the social behavior in the adult life, BALB/c mice were exposed to clean air (control, DE, DE-SOA and gas without any particulate matter in the inhala-tion chambers from gestational day 14 to postnatal day 21 for 5 h a day and 5 days per week. Then adult mice were examined for changes in their social behavior at the age of 13 week by a sociability and social novelty preference, social interaction with a juvenile mouse and light-dark transition test, hypothalamic mRNA expression levels of social behavior-related genes, estrogen receptor-alpha and oxytocin receptor as well as of the oxidative stress marker gene, heme oxygenase (HO-1 by real-time RT-PCR method. In addition, hypothalamic level of neuronal excitatory marker, glutamate was determined by ELISA method. We observed that sociability and social novelty pref-erence as well as social interaction were remarkably impaired, expression levels of es-trogen receptor-alpha, oxytocin receptor mRNAs were significantly decreased, ex-pression levels of HO-1 mRNAs and glutamate levels were significantly increased in adult male mice exposed to DE-SOA compared to the control ones. Findings of this study indicate early life exposure of BALB/c mice to DE-SOA may affect their late-onset hypothalamic expression of social behavior related genes, trigger neurotoxi-city and impair social behavior in the males.

  10. Student Development and Developmental Studies.

    Science.gov (United States)

    Champaigne, John

    1982-01-01

    Reviews the nine-stage Perry Scheme of Intellectual and Ethical Development, detailing three major student orientations--dualism, multiplicity, and commitments in relativism. Suggests techniques developmental educators can use to communicate with, support, and challenge students to promote intellectual development. Underscores the importance of…

  11. Homogenization of discrete media

    Energy Technology Data Exchange (ETDEWEB)

    Pradel, F.; Sab, K. [CERAM-ENPC, Marne-la-Vallee (France)

    1998-11-01

    Material such as granular media, beam assembly are easily seen as discrete media. They look like geometrical points linked together thanks to energetic expressions. Our purpose is to extend discrete kinematics to the one of an equivalent continuous material. First we explain how we build the localisation tool for periodic materials according to estimated continuum medium type (classical Cauchy, and Cosserat media). Once the bridge built between discrete and continuum media, we exhibit its application over two bidimensional beam assembly structures : the honey comb and a structural reinforced variation. The new behavior is then applied for the simple plan shear problem in a Cosserat continuum and compared with the real discrete solution. By the mean of this example, we establish the agreement of our new model with real structures. The exposed method has a longer range than mechanics and can be applied to every discrete problems like electromagnetism in which relationship between geometrical points can be summed up by an energetic function. (orig.) 7 refs.

  12. DISCRETE MATHEMATICS/NUMBER THEORY

    OpenAIRE

    Mrs. Manju Devi*

    2017-01-01

    Discrete mathematics is the study of mathematical structures that are fundamentally discrete rather than continuous. In contrast to real numbers that have the property of varying "smoothly", the objects studied in discrete mathematics such as integers, graphs, and statements do not vary smoothly in this way, but have distinct, separated values. Discrete mathematics therefore excludes topics in "continuous mathematics" such as calculus and analysis. Discrete objects can often be enumerated by ...

  13. Discrete-Event Simulation

    Directory of Open Access Journals (Sweden)

    Prateek Sharma

    2015-04-01

    Full Text Available Abstract Simulation can be regarded as the emulation of the behavior of a real-world system over an interval of time. The process of simulation relies upon the generation of the history of a system and then analyzing that history to predict the outcome and improve the working of real systems. Simulations can be of various kinds but the topic of interest here is one of the most important kind of simulation which is Discrete-Event Simulation which models the system as a discrete sequence of events in time. So this paper aims at introducing about Discrete-Event Simulation and analyzing how it is beneficial to the real world systems.

  14. Discrete systems and integrability

    CERN Document Server

    Hietarinta, J; Nijhoff, F W

    2016-01-01

    This first introductory text to discrete integrable systems introduces key notions of integrability from the vantage point of discrete systems, also making connections with the continuous theory where relevant. While treating the material at an elementary level, the book also highlights many recent developments. Topics include: Darboux and Bäcklund transformations; difference equations and special functions; multidimensional consistency of integrable lattice equations; associated linear problems (Lax pairs); connections with Padé approximants and convergence algorithms; singularities and geometry; Hirota's bilinear formalism for lattices; intriguing properties of discrete Painlevé equations; and the novel theory of Lagrangian multiforms. The book builds the material in an organic way, emphasizing interconnections between the various approaches, while the exposition is mostly done through explicit computations on key examples. Written by respected experts in the field, the numerous exercises and the thoroug...

  15. Discrete Sparse Coding.

    Science.gov (United States)

    Exarchakis, Georgios; Lücke, Jörg

    2017-11-01

    Sparse coding algorithms with continuous latent variables have been the subject of a large number of studies. However, discrete latent spaces for sparse coding have been largely ignored. In this work, we study sparse coding with latents described by discrete instead of continuous prior distributions. We consider the general case in which the latents (while being sparse) can take on any value of a finite set of possible values and in which we learn the prior probability of any value from data. This approach can be applied to any data generated by discrete causes, and it can be applied as an approximation of continuous causes. As the prior probabilities are learned, the approach then allows for estimating the prior shape without assuming specific functional forms. To efficiently train the parameters of our probabilistic generative model, we apply a truncated expectation-maximization approach (expectation truncation) that we modify to work with a general discrete prior. We evaluate the performance of the algorithm by applying it to a variety of tasks: (1) we use artificial data to verify that the algorithm can recover the generating parameters from a random initialization, (2) use image patches of natural images and discuss the role of the prior for the extraction of image components, (3) use extracellular recordings of neurons to present a novel method of analysis for spiking neurons that includes an intuitive discretization strategy, and (4) apply the algorithm on the task of encoding audio waveforms of human speech. The diverse set of numerical experiments presented in this letter suggests that discrete sparse coding algorithms can scale efficiently to work with realistic data sets and provide novel statistical quantities to describe the structure of the data.

  16. Introductory discrete mathematics

    CERN Document Server

    Balakrishnan, V K

    2010-01-01

    This concise text offers an introduction to discrete mathematics for undergraduate students in computer science and mathematics. Mathematics educators consider it vital that their students be exposed to a course in discrete methods that introduces them to combinatorial mathematics and to algebraic and logical structures focusing on the interplay between computer science and mathematics. The present volume emphasizes combinatorics, graph theory with applications to some stand network optimization problems, and algorithms to solve these problems.Chapters 0-3 cover fundamental operations involv

  17. Discrete-Event Simulation

    OpenAIRE

    Prateek Sharma

    2015-01-01

    Abstract Simulation can be regarded as the emulation of the behavior of a real-world system over an interval of time. The process of simulation relies upon the generation of the history of a system and then analyzing that history to predict the outcome and improve the working of real systems. Simulations can be of various kinds but the topic of interest here is one of the most important kind of simulation which is Discrete-Event Simulation which models the system as a discrete sequence of ev...

  18. Infant differential behavioral responding to discrete emotions.

    Science.gov (United States)

    Walle, Eric A; Reschke, Peter J; Camras, Linda A; Campos, Joseph J

    2017-10-01

    Emotional communication regulates the behaviors of social partners. Research on individuals' responding to others' emotions typically compares responses to a single negative emotion compared with responses to a neutral or positive emotion. Furthermore, coding of such responses routinely measure surface level features of the behavior (e.g., approach vs. avoidance) rather than its underlying function (e.g., the goal of the approach or avoidant behavior). This investigation examined infants' responding to others' emotional displays across 5 discrete emotions: joy, sadness, fear, anger, and disgust. Specifically, 16-, 19-, and 24-month-old infants observed an adult communicate a discrete emotion toward a stimulus during a naturalistic interaction. Infants' responses were coded to capture the function of their behaviors (e.g., exploration, prosocial behavior, and security seeking). The results revealed a number of instances indicating that infants use different functional behaviors in response to discrete emotions. Differences in behaviors across emotions were clearest in the 24-month-old infants, though younger infants also demonstrated some differential use of behaviors in response to discrete emotions. This is the first comprehensive study to identify differences in how infants respond with goal-directed behaviors to discrete emotions. Additionally, the inclusion of a function-based coding scheme and interpersonal paradigms may be informative for future emotion research with children and adults. Possible developmental accounts for the observed behaviors and the benefits of coding techniques emphasizing the function of social behavior over their form are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. The effect of ultraviolet-B radiation on gene expression and pigment composition in etiolated and green pea leaf tissue: UV-B-induced changes are gene-specific and dependent upon the developmental stage

    International Nuclear Information System (INIS)

    Jordan, B.R.; James, P.E.; Strid, A.; Anthony, R.G.

    1994-01-01

    present in low or undetectable amounts in control tissues. In green leaf tissue exposed to supplementary UV-B, a transient increase was detected. The transcripts for chs reached a maximum level after approximately 8 h UV-B exposure, and then declined to lower levels over subsequent days of diurnal photoperiods. However, a constant increase in chs was found after continuous exposure to UV-B for up to 30 h. In etiolated tissue, either white-light, supplementary UV-B or UV-B alone gave small increases in chs, only 8 h of UV-B radiation alone gave any substantial increase in chs expression. Overall, these results clearly demonstrate that the response to increased levels of UV-B radiation is dependent upon the developmental stage of the tissue and involves complex changes in gene expression. (author)

  20. Discrete-Time Systems

    Indian Academy of Sciences (India)

    We also describe discrete-time systems in terms of difference ... A more modern alternative, especially for larger systems, is to convert ... In other words, ..... picture?) State-variable equations are also called state-space equations because the ...

  1. Discrete Lorentzian quantum gravity

    NARCIS (Netherlands)

    Loll, R.

    2000-01-01

    Just as for non-abelian gauge theories at strong coupling, discrete lattice methods are a natural tool in the study of non-perturbative quantum gravity. They have to reflect the fact that the geometric degrees of freedom are dynamical, and that therefore also the lattice theory must be formulated

  2. What Is Discrete Mathematics?

    Science.gov (United States)

    Sharp, Karen Tobey

    This paper cites information received from a number of sources, e.g., mathematics teachers in two-year colleges, publishers, and convention speakers, about the nature of discrete mathematics and about what topics a course in this subject should contain. Note is taken of the book edited by Ralston and Young which discusses the future of college…

  3. Stage line diagram: an age-conditional reference diagram for tracking development.

    Science.gov (United States)

    van Buuren, Stef; Ooms, Jeroen C L

    2009-05-15

    This paper presents a method for calculating stage line diagrams, a novel type of reference diagram useful for tracking developmental processes over time. Potential fields of applications include: dentistry (tooth eruption), oncology (tumor grading, cancer staging), virology (HIV infection and disease staging), psychology (stages of cognitive development), human development (pubertal stages) and chronic diseases (stages of dementia). Transition probabilities between successive stages are modeled as smoothly varying functions of age. Age-conditional references are calculated from the modeled probabilities by the mid-P value. It is possible to eliminate the influence of age by calculating standard deviation scores (SDS). The method is applied to the empirical data to produce reference charts on secondary sexual maturation. The mean of the empirical SDS in the reference population is close to zero, whereas the variance depends on age. The stage line diagram provides quick insight into both status (in SDS) and tempo (in SDS/year) of development of an individual child. Other measures (e.g. height SDS, body mass index SDS) from the same child can be added to the chart. Diagrams for sexual maturation are available as a web application at http://vps.stefvanbuuren.nl/puberty. The stage line diagram expresses status and tempo of discrete changes on a continuous scale. Wider application of these measures scores opens up new analytic possibilities. (c) 2009 John Wiley & Sons, Ltd.

  4. Discrete Exterior Calculus Discretization of Incompressible Navier-Stokes Equations

    KAUST Repository

    Mohamed, Mamdouh S.; Hirani, Anil N.; Samtaney, Ravi

    2017-01-01

    A conservative discretization of incompressible Navier-Stokes equations over surface simplicial meshes is developed using discrete exterior calculus (DEC). Numerical experiments for flows over surfaces reveal a second order accuracy

  5. Developmental Perspectives on Nutrition and Obesity From Gestation to Adolescence

    OpenAIRE

    Huang, Terry T.; Esposito, Layla; Fisher, Jennifer O.; Mennella, Julie A.; Hoelscher, Deanna M.

    2009-01-01

    Obesity results from a complex combination of factors that act at many stages throughout a person's life. Therefore, examining childhood nutrition and obesity from a developmental perspective is warranted. A developmental perspective recognizes the cumulative effects of factors that contribute to eating behavior and obesity, including biological and socioenvironmental factors that are relevant at different stages of development. A developmental perspective considers family, school, and commun...

  6. Discrete mKdV and discrete sine-Gordon flows on discrete space curves

    International Nuclear Information System (INIS)

    Inoguchi, Jun-ichi; Kajiwara, Kenji; Matsuura, Nozomu; Ohta, Yasuhiro

    2014-01-01

    In this paper, we consider the discrete deformation of the discrete space curves with constant torsion described by the discrete mKdV or the discrete sine-Gordon equations, and show that it is formulated as the torsion-preserving equidistant deformation on the osculating plane which satisfies the isoperimetric condition. The curve is reconstructed from the deformation data by using the Sym–Tafel formula. The isoperimetric equidistant deformation of the space curves does not preserve the torsion in general. However, it is possible to construct the torsion-preserving deformation by tuning the deformation parameters. Further, it is also possible to make an arbitrary choice of the deformation described by the discrete mKdV equation or by the discrete sine-Gordon equation at each step. We finally show that the discrete deformation of discrete space curves yields the discrete K-surfaces. (paper)

  7. Discrete dynamic modeling of cellular signaling networks.

    Science.gov (United States)

    Albert, Réka; Wang, Rui-Sheng

    2009-01-01

    Understanding signal transduction in cellular systems is a central issue in systems biology. Numerous experiments from different laboratories generate an abundance of individual components and causal interactions mediating environmental and developmental signals. However, for many signal transduction systems there is insufficient information on the overall structure and the molecular mechanisms involved in the signaling network. Moreover, lack of kinetic and temporal information makes it difficult to construct quantitative models of signal transduction pathways. Discrete dynamic modeling, combined with network analysis, provides an effective way to integrate fragmentary knowledge of regulatory interactions into a predictive mathematical model which is able to describe the time evolution of the system without the requirement for kinetic parameters. This chapter introduces the fundamental concepts of discrete dynamic modeling, particularly focusing on Boolean dynamic models. We describe this method step-by-step in the context of cellular signaling networks. Several variants of Boolean dynamic models including threshold Boolean networks and piecewise linear systems are also covered, followed by two examples of successful application of discrete dynamic modeling in cell biology.

  8. Developmental dyscalculia.

    Science.gov (United States)

    Kucian, Karin; von Aster, Michael

    2015-01-01

    Numerical skills are essential in our everyday life, and impairments in the development of number processing and calculation have a negative impact on schooling and professional careers. Approximately 3 to 6 % of children are affected from specific disorders of numerical understanding (developmental dyscalculia (DD)). Impaired development of number processing skills in these children is characterized by problems in various aspects of numeracy as well as alterations of brain activation and brain structure. Moreover, DD is assumed to be a very heterogeneous disorder putting special challenges to define homogeneous diagnostic criteria. Finally, interdisciplinary perspectives from psychology, neuroscience and education can contribute to the design for interventions, and although results are still sparse, they are promising and have shown positive effects on behaviour as well as brain function. In the current review, we are going to give an overview about typical and atypical development of numerical abilities at the behavioural and neuronal level. Furthermore, current status and obstacles in the definition and diagnostics of DD are discussed, and finally, relevant points that should be considered to make an intervention as successful as possible are summarized.

  9. Discrete mathematics with applications

    CERN Document Server

    Koshy, Thomas

    2003-01-01

    This approachable text studies discrete objects and the relationsips that bind them. It helps students understand and apply the power of discrete math to digital computer systems and other modern applications. It provides excellent preparation for courses in linear algebra, number theory, and modern/abstract algebra and for computer science courses in data structures, algorithms, programming languages, compilers, databases, and computation.* Covers all recommended topics in a self-contained, comprehensive, and understandable format for students and new professionals * Emphasizes problem-solving techniques, pattern recognition, conjecturing, induction, applications of varying nature, proof techniques, algorithm development and correctness, and numeric computations* Weaves numerous applications into the text* Helps students learn by doing with a wealth of examples and exercises: - 560 examples worked out in detail - More than 3,700 exercises - More than 150 computer assignments - More than 600 writing projects*...

  10. Discrete and computational geometry

    CERN Document Server

    Devadoss, Satyan L

    2011-01-01

    Discrete geometry is a relatively new development in pure mathematics, while computational geometry is an emerging area in applications-driven computer science. Their intermingling has yielded exciting advances in recent years, yet what has been lacking until now is an undergraduate textbook that bridges the gap between the two. Discrete and Computational Geometry offers a comprehensive yet accessible introduction to this cutting-edge frontier of mathematics and computer science. This book covers traditional topics such as convex hulls, triangulations, and Voronoi diagrams, as well as more recent subjects like pseudotriangulations, curve reconstruction, and locked chains. It also touches on more advanced material, including Dehn invariants, associahedra, quasigeodesics, Morse theory, and the recent resolution of the Poincaré conjecture. Connections to real-world applications are made throughout, and algorithms are presented independently of any programming language. This richly illustrated textbook also fe...

  11. Lectures on discrete geometry

    CERN Document Server

    2002-01-01

    Discrete geometry investigates combinatorial properties of configurations of geometric objects. To a working mathematician or computer scientist, it offers sophisticated results and techniques of great diversity and it is a foundation for fields such as computational geometry or combinatorial optimization. This book is primarily a textbook introduction to various areas of discrete geometry. In each area, it explains several key results and methods, in an accessible and concrete manner. It also contains more advanced material in separate sections and thus it can serve as a collection of surveys in several narrower subfields. The main topics include: basics on convex sets, convex polytopes, and hyperplane arrangements; combinatorial complexity of geometric configurations; intersection patterns and transversals of convex sets; geometric Ramsey-type results; polyhedral combinatorics and high-dimensional convexity; and lastly, embeddings of finite metric spaces into normed spaces. Jiri Matousek is Professor of Com...

  12. Time Discretization Techniques

    KAUST Repository

    Gottlieb, S.

    2016-10-12

    The time discretization of hyperbolic partial differential equations is typically the evolution of a system of ordinary differential equations obtained by spatial discretization of the original problem. Methods for this time evolution include multistep, multistage, or multiderivative methods, as well as a combination of these approaches. The time step constraint is mainly a result of the absolute stability requirement, as well as additional conditions that mimic physical properties of the solution, such as positivity or total variation stability. These conditions may be required for stability when the solution develops shocks or sharp gradients. This chapter contains a review of some of the methods historically used for the evolution of hyperbolic PDEs, as well as cutting edge methods that are now commonly used.

  13. Discrete pseudo-integrals

    Czech Academy of Sciences Publication Activity Database

    Mesiar, Radko; Li, J.; Pap, E.

    2013-01-01

    Roč. 54, č. 3 (2013), s. 357-364 ISSN 0888-613X R&D Projects: GA ČR GAP402/11/0378 Institutional support: RVO:67985556 Keywords : concave integral * pseudo-addition * pseudo-multiplication Subject RIV: BA - General Mathematics Impact factor: 1.977, year: 2013 http://library.utia.cas.cz/separaty/2013/E/mesiar-discrete pseudo-integrals.pdf

  14. Discrete variational Hamiltonian mechanics

    International Nuclear Information System (INIS)

    Lall, S; West, M

    2006-01-01

    The main contribution of this paper is to present a canonical choice of a Hamiltonian theory corresponding to the theory of discrete Lagrangian mechanics. We make use of Lagrange duality and follow a path parallel to that used for construction of the Pontryagin principle in optimal control theory. We use duality results regarding sensitivity and separability to show the relationship between generating functions and symplectic integrators. We also discuss connections to optimal control theory and numerical algorithms

  15. Discrete Routh reduction

    International Nuclear Information System (INIS)

    Jalnapurkar, Sameer M; Leok, Melvin; Marsden, Jerrold E; West, Matthew

    2006-01-01

    This paper develops the theory of Abelian Routh reduction for discrete mechanical systems and applies it to the variational integration of mechanical systems with Abelian symmetry. The reduction of variational Runge-Kutta discretizations is considered, as well as the extent to which symmetry reduction and discretization commute. These reduced methods allow the direct simulation of dynamical features such as relative equilibria and relative periodic orbits that can be obscured or difficult to identify in the unreduced dynamics. The methods are demonstrated for the dynamics of an Earth orbiting satellite with a non-spherical J 2 correction, as well as the double spherical pendulum. The J 2 problem is interesting because in the unreduced picture, geometric phases inherent in the model and those due to numerical discretization can be hard to distinguish, but this issue does not appear in the reduced algorithm, where one can directly observe interesting dynamical structures in the reduced phase space (the cotangent bundle of shape space), in which the geometric phases have been removed. The main feature of the double spherical pendulum example is that it has a non-trivial magnetic term in its reduced symplectic form. Our method is still efficient as it can directly handle the essential non-canonical nature of the symplectic structure. In contrast, a traditional symplectic method for canonical systems could require repeated coordinate changes if one is evoking Darboux' theorem to transform the symplectic structure into canonical form, thereby incurring additional computational cost. Our method allows one to design reduced symplectic integrators in a natural way, despite the non-canonical nature of the symplectic structure

  16. Discrete port-Hamiltonian systems

    NARCIS (Netherlands)

    Talasila, V.; Clemente-Gallardo, J.; Schaft, A.J. van der

    2006-01-01

    Either from a control theoretic viewpoint or from an analysis viewpoint it is necessary to convert smooth systems to discrete systems, which can then be implemented on computers for numerical simulations. Discrete models can be obtained either by discretizing a smooth model, or by directly modeling

  17. A paradigm for discrete physics

    International Nuclear Information System (INIS)

    Noyes, H.P.; McGoveran, D.; Etter, T.; Manthey, M.J.; Gefwert, C.

    1987-01-01

    An example is outlined for constructing a discrete physics using as a starting point the insight from quantum physics that events are discrete, indivisible and non-local. Initial postulates are finiteness, discreteness, finite computability, absolute nonuniqueness (i.e., homogeneity in the absence of specific cause) and additivity

  18. Assessment of Growth Using Mandibular Canine Calcification Stages and Its Correlation with Modified MP3 Stages.

    Science.gov (United States)

    Nayak, Reshma; Nayak, Us Krishna; Hegde, Gautam

    2010-01-01

    Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. A total of 160 periapical radiographs (80 males and 80 females), of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian's stages of dental calcification and the modified MP3 stages. The correlation between the developmental stages of MP3 and the mandibular right canine in male and female groups, is of high statistical significance (p = 0.001). The correlation coefficient between MP3 stages and developmental stages of mandibular canine and chronological age in male and females was found to be not significant. The correlation between the mandibular canine calcification stages and MP3 stages was found to be significant. The developmental stages of the mandibular canine could be used very reliably as a sole indicator for assessment of skeletal maturity.

  19. Ecdysone Control of Developmental Transitions

    DEFF Research Database (Denmark)

    Rewitz, Kim; Yamanaka, Naoki; O'Connor, Michael B.

    2013-01-01

    The steroid hormone ecdysone is the central regulator of insect developmental transitions. Recent new advances in our understanding of ecdysone action have relied heavily on the application of Drosophila melanogaster molecular genetic tools to study insect metamorphosis. In this review, we focus...... on three major aspects of Drosophila ecdysone biology: (a) factors that regulate the timing of ecdysone release, (b) molecular basis of stage- and tissue-specific responses to ecdysone, and (c) feedback regulation and coordination of ecdysone signaling....

  20. Two new discrete integrable systems

    International Nuclear Information System (INIS)

    Chen Xiao-Hong; Zhang Hong-Qing

    2013-01-01

    In this paper, we focus on the construction of new (1+1)-dimensional discrete integrable systems according to a subalgebra of loop algebra à 1 . By designing two new (1+1)-dimensional discrete spectral problems, two new discrete integrable systems are obtained, namely, a 2-field lattice hierarchy and a 3-field lattice hierarchy. When deriving the two new discrete integrable systems, we find the generalized relativistic Toda lattice hierarchy and the generalized modified Toda lattice hierarchy. Moreover, we also obtain the Hamiltonian structures of the two lattice hierarchies by means of the discrete trace identity

  1. [Contemporary cognitive theories about developmental dyscalculia].

    Science.gov (United States)

    Castro-Cañizares, D; Estévez-Pérez, N; Reigosa-Crespo, V

    To analyze the current theories describing the cognitive mechanisms underlying developmental dyscalculia. The four most researched hypotheses concerning the cognitive deficits related to developmental dyscalculia, as well as experimental evidences supporting or refusing them are presented. The first hypothesis states that developmental dyscalculia is consequence of domain general cognitive deficits. The second hypothesis suggests that it is due to a failure in the development of specialized brain systems dedicated to numerosity processing. The third hypothesis asserts the disorder is caused by a deficit in accessing quantity representation through numerical symbols. The last hypothesis states developmental dyscalculia appears as a consequence of impairments in a generalized magnitude system dedicated to the processing of continuous and discrete magnitudes. None of the hypotheses has been proven more plausible than the rest. Relevant issues rose by them need to be revisited and answered in the light of new experimental designs. In the last years the understanding of cognitive disorders involved in developmental dyscalculia has remarkably increased, but it is nonetheless insufficient. Additional research is required in order to achieve a comprehensive cognitive model of numerical processing development and its disorders. This will improve the diagnostic precision and the effectiveness of developmental dyscalculia intervention strategies.

  2. A stage is a stage is a stage: a direct comparison of two scoring systems.

    Science.gov (United States)

    Dawson, Theo L

    2003-09-01

    L. Kohlberg (1969) argued that his moral stages captured a developmental sequence specific to the moral domain. To explore that contention, the author compared stage assignments obtained with the Standard Issue Scoring System (A. Colby & L. Kohlberg, 1987a, 1987b) and those obtained with a generalized content-independent stage-scoring system called the Hierarchical Complexity Scoring System (T. L. Dawson, 2002a), on 637 moral judgment interviews (participants' ages ranged from 5 to 86 years). The correlation between stage scores produced with the 2 systems was .88. Although standard issue scoring and hierarchical complexity scoring often awarded different scores up to Kohlberg's Moral Stage 2/3, from his Moral Stage 3 onward, scores awarded with the two systems predominantly agreed. The author explores the implications for developmental research.

  3. Dissociation between face perception and face memory in adults, but not children, with developmental prosopagnosia.

    Science.gov (United States)

    Dalrymple, Kirsten A; Garrido, Lúcia; Duchaine, Brad

    2014-10-01

    Cognitive models propose that face recognition is accomplished through a series of discrete stages, including perceptual representation of facial structure, and encoding and retrieval of facial information. This implies that impaired face recognition can result from failures of face perception, face memory, or both. Studies of acquired prosopagnosia, autism spectrum disorders, and the development of normal face recognition support the idea that face perception and face memory are distinct processes, yet this distinction has received little attention in developmental prosopagnosia (DP). To address this issue, we tested the face perception and face memory of children and adults with DP. By definition, face memory is impaired in DP, so memory deficits were present in all participants. However, we found that all children, but only half of the adults had impaired face perception. Thus, results from adults indicate that face perception and face memory are dissociable, while the results from children provide no evidence for this division. Importantly, our findings raise the possibility that DP is qualitatively different in childhood versus adulthood. We discuss theoretical explanations for this developmental pattern and conclude that longitudinal studies are necessary to better understand the developmental trajectory of face perception and face memory deficits in DP. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Dissociation between face perception and face memory in adults, but not children, with developmental prosopagnosia

    Directory of Open Access Journals (Sweden)

    Kirsten A. Dalrymple

    2014-10-01

    Full Text Available Cognitive models propose that face recognition is accomplished through a series of discrete stages, including perceptual representation of facial structure, and encoding and retrieval of facial information. This implies that impaired face recognition can result from failures of face perception, face memory, or both. Studies of acquired prosopagnosia, autism spectrum disorders, and the development of normal face recognition support the idea that face perception and face memory are distinct processes, yet this distinction has received little attention in developmental prosopagnosia (DP. To address this issue, we tested the face perception and face memory of children and adults with DP. By definition, face memory is impaired in DP, so memory deficits were present in all participants. However, we found that all children, but only half of the adults had impaired face perception. Thus, results from adults indicate that face perception and face memory are dissociable, while the results from children provide no evidence for this division. Importantly, our findings raise the possibility that DP is qualitatively different in childhood versus adulthood. We discuss theoretical explanations for this developmental pattern and conclude that longitudinal studies are necessary to better understand the developmental trajectory of face perception and face memory deficits in DP.

  5. Discrete dark matter

    CERN Document Server

    Hirsch, M; Peinado, E; Valle, J W F

    2010-01-01

    We propose a new motivation for the stability of dark matter (DM). We suggest that the same non-abelian discrete flavor symmetry which accounts for the observed pattern of neutrino oscillations, spontaneously breaks to a Z2 subgroup which renders DM stable. The simplest scheme leads to a scalar doublet DM potentially detectable in nuclear recoil experiments, inverse neutrino mass hierarchy, hence a neutrinoless double beta decay rate accessible to upcoming searches, while reactor angle equal to zero gives no CP violation in neutrino oscillations.

  6. Discrete Dynamics Lab

    Science.gov (United States)

    Wuensche, Andrew

    DDLab is interactive graphics software for creating, visualizing, and analyzing many aspects of Cellular Automata, Random Boolean Networks, and Discrete Dynamical Networks in general and studying their behavior, both from the time-series perspective — space-time patterns, and from the state-space perspective — attractor basins. DDLab is relevant to research, applications, and education in the fields of complexity, self-organization, emergent phenomena, chaos, collision-based computing, neural networks, content addressable memory, genetic regulatory networks, dynamical encryption, generative art and music, and the study of the abstract mathematical/physical/dynamical phenomena in their own right.

  7. Developmental neuroimaging

    Energy Technology Data Exchange (ETDEWEB)

    Dehaene-Lambertz, G. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), INSERM U562, 91 - Orsay (France)

    2006-07-01

    Cognitive capacities, such as language, mathematics, music, etc... are highly developed in humans as compared to animals. Numerous studies have found precursors of these capacities in infants: For example, infants are able to discriminate sentences in different languages (Mehler et al., 1988), distinguish sets of objects based on their numerosity (Feigenson et al., 2002) or recognize known faces (Bushnell, 1982). These abilities are not very different from those of other animals. Monkeys are also able to discriminate two human languages (Ramus et al., 2000), two quantities of items (Hauser et al., 2002), or respond to particular faces (Parr et al., 2000). In a few years, however, children surpass these animals. To explain the development of the cognitive capacities of our species, our approach consists in studying the initial stages of cerebral organization during the first months of life in order to characterize the critical parameters that allow infants to take advantage of their environment to achieve the adults' cognitive sophistication. Thanks to the recent progress of brain imaging, it is now possible to examine cerebral functioning of the very young child in entire security. In our team, we used two complementary methods: event-related potentials (ERPs) and functional magnetic resonance imaging (f MRI). ERPs, used since numerous years in infants, consist of the recording of the brain electrical activity consecutive to the presentation of a stimulus. By using a careful experimental design, it is possible to infer the succession of processing stages that the stimulus follows and to measure their latency (Dehaene-Lambertz and Dehaene, 1994; Gliga and Dehaene-Lambertz, 2006). High-density ERPs system allows also to record even small topographical differences between conditions and thus to infer that the underlying network s involved in the tested conditions are different. With this method, we have decomposed syllable perception in infants and underscore a

  8. Developmental neuroimaging

    International Nuclear Information System (INIS)

    Dehaene-Lambertz, G.

    2006-01-01

    Cognitive capacities, such as language, mathematics, music, etc... are highly developed in humans as compared to animals. Numerous studies have found precursors of these capacities in infants: For example, infants are able to discriminate sentences in different languages (Mehler et al., 1988), distinguish sets of objects based on their numerosity (Feigenson et al., 2002) or recognize known faces (Bushnell, 1982). These abilities are not very different from those of other animals. Monkeys are also able to discriminate two human languages (Ramus et al., 2000), two quantities of items (Hauser et al., 2002), or respond to particular faces (Parr et al., 2000). In a few years, however, children surpass these animals. To explain the development of the cognitive capacities of our species, our approach consists in studying the initial stages of cerebral organization during the first months of life in order to characterize the critical parameters that allow infants to take advantage of their environment to achieve the adults' cognitive sophistication. Thanks to the recent progress of brain imaging, it is now possible to examine cerebral functioning of the very young child in entire security. In our team, we used two complementary methods: event-related potentials (ERPs) and functional magnetic resonance imaging (f MRI). ERPs, used since numerous years in infants, consist of the recording of the brain electrical activity consecutive to the presentation of a stimulus. By using a careful experimental design, it is possible to infer the succession of processing stages that the stimulus follows and to measure their latency (Dehaene-Lambertz and Dehaene, 1994; Gliga and Dehaene-Lambertz, 2006). High-density ERPs system allows also to record even small topographical differences between conditions and thus to infer that the underlying network s involved in the tested conditions are different. With this method, we have decomposed syllable perception in infants and underscore a

  9. Finite discrete field theory

    International Nuclear Information System (INIS)

    Souza, Manoelito M. de

    1997-01-01

    We discuss the physical meaning and the geometric interpretation of implementation in classical field theories. The origin of infinities and other inconsistencies in field theories is traced to fields defined with support on the light cone; a finite and consistent field theory requires a light-cone generator as the field support. Then, we introduce a classical field theory with support on the light cone generators. It results on a description of discrete (point-like) interactions in terms of localized particle-like fields. We find the propagators of these particle-like fields and discuss their physical meaning, properties and consequences. They are conformally invariant, singularity-free, and describing a manifestly covariant (1 + 1)-dimensional dynamics in a (3 = 1) spacetime. Remarkably this conformal symmetry remains even for the propagation of a massive field in four spacetime dimensions. We apply this formalism to Classical electrodynamics and to the General Relativity Theory. The standard formalism with its distributed fields is retrieved in terms of spacetime average of the discrete field. Singularities are the by-products of the averaging process. This new formalism enlighten the meaning and the problem of field theory, and may allow a softer transition to a quantum theory. (author)

  10. Developmental toxicity of engineered nanomaterials in rodents

    Energy Technology Data Exchange (ETDEWEB)

    Ema, Makoto, E-mail: ema-makoto@aist.go.jp; Gamo, Masashi; Honda, Kazumasa

    2016-05-15

    We summarized significant effects reported in the literature on the developmental toxicity of engineered nanomaterials (ENMs) in rodents. The developmental toxicity of ENMs included not only structural abnormalities, but also death, growth retardation, and behavioral and functional abnormalities. Most studies were performed on mice using an injection route of exposure. Teratogenic effects were indicated when multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), and TiO{sub 2}-nanoparticles were administered to mice during early gestation. Reactive oxygen species levels were increased in placentas and malformed fetuses and their placentas after prenatal exposure to MWCNTs and SWCNTs, respectively. The pre- and postnatal mortalities and growth retardation in offspring increased after prenatal exposure to ENMs. Histopathological and functional abnormalities were also induced in placentas after prenatal exposure to ENMs. Maternal exposure to ENMs induced behavioral alterations, histopathological and biochemical changes in the central nervous system, increased susceptibility to allergy, transplacental genotoxicity, and vascular, immunological, and reproductive effects in offspring. The size- and developmental stage-dependent placental transfer of ENMs was noted after maternal exposure. Silver accumulated in the visceral yolk sac after being injected with Ag-NPs during early gestation. Although currently available data has provided initial information on the potential developmental toxicity of ENMs, that on the developmental toxicity of ENMs is still very limited. Further studies using well-characterized ENMs, state-of the-art study protocols, and appropriate routes of exposure are required in order to clarify these developmental effects and provide information suitable for risk assessments of ENMs. - Highlights: • We review the developmental toxicity studies of engineered nanomaterials (ENMs). • Various developmental endpoints have been

  11. Discrete Exterior Calculus Discretization of Incompressible Navier-Stokes Equations

    KAUST Repository

    Mohamed, Mamdouh S.

    2017-05-23

    A conservative discretization of incompressible Navier-Stokes equations over surface simplicial meshes is developed using discrete exterior calculus (DEC). Numerical experiments for flows over surfaces reveal a second order accuracy for the developed scheme when using structured-triangular meshes, and first order accuracy otherwise. The mimetic character of many of the DEC operators provides exact conservation of both mass and vorticity, in addition to superior kinetic energy conservation. The employment of barycentric Hodge star allows the discretization to admit arbitrary simplicial meshes. The discretization scheme is presented along with various numerical test cases demonstrating its main characteristics.

  12. Advances in discrete differential geometry

    CERN Document Server

    2016-01-01

    This is one of the first books on a newly emerging field of discrete differential geometry and an excellent way to access this exciting area. It surveys the fascinating connections between discrete models in differential geometry and complex analysis, integrable systems and applications in computer graphics. The authors take a closer look at discrete models in differential geometry and dynamical systems. Their curves are polygonal, surfaces are made from triangles and quadrilaterals, and time is discrete. Nevertheless, the difference between the corresponding smooth curves, surfaces and classical dynamical systems with continuous time can hardly be seen. This is the paradigm of structure-preserving discretizations. Current advances in this field are stimulated to a large extent by its relevance for computer graphics and mathematical physics. This book is written by specialists working together on a common research project. It is about differential geometry and dynamical systems, smooth and discrete theories, ...

  13. Poisson hierarchy of discrete strings

    International Nuclear Information System (INIS)

    Ioannidou, Theodora; Niemi, Antti J.

    2016-01-01

    The Poisson geometry of a discrete string in three dimensional Euclidean space is investigated. For this the Frenet frames are converted into a spinorial representation, the discrete spinor Frenet equation is interpreted in terms of a transfer matrix formalism, and Poisson brackets are introduced in terms of the spinor components. The construction is then generalised, in a self-similar manner, into an infinite hierarchy of Poisson algebras. As an example, the classical Virasoro (Witt) algebra that determines reparametrisation diffeomorphism along a continuous string, is identified as a particular sub-algebra, in the hierarchy of the discrete string Poisson algebra. - Highlights: • Witt (classical Virasoro) algebra is derived in the case of discrete string. • Infinite dimensional hierarchy of Poisson bracket algebras is constructed for discrete strings. • Spinor representation of discrete Frenet equations is developed.

  14. Poisson hierarchy of discrete strings

    Energy Technology Data Exchange (ETDEWEB)

    Ioannidou, Theodora, E-mail: ti3@auth.gr [Faculty of Civil Engineering, School of Engineering, Aristotle University of Thessaloniki, 54249, Thessaloniki (Greece); Niemi, Antti J., E-mail: Antti.Niemi@physics.uu.se [Department of Physics and Astronomy, Uppsala University, P.O. Box 803, S-75108, Uppsala (Sweden); Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Fédération Denis Poisson, Université de Tours, Parc de Grandmont, F37200, Tours (France); Department of Physics, Beijing Institute of Technology, Haidian District, Beijing 100081 (China)

    2016-01-28

    The Poisson geometry of a discrete string in three dimensional Euclidean space is investigated. For this the Frenet frames are converted into a spinorial representation, the discrete spinor Frenet equation is interpreted in terms of a transfer matrix formalism, and Poisson brackets are introduced in terms of the spinor components. The construction is then generalised, in a self-similar manner, into an infinite hierarchy of Poisson algebras. As an example, the classical Virasoro (Witt) algebra that determines reparametrisation diffeomorphism along a continuous string, is identified as a particular sub-algebra, in the hierarchy of the discrete string Poisson algebra. - Highlights: • Witt (classical Virasoro) algebra is derived in the case of discrete string. • Infinite dimensional hierarchy of Poisson bracket algebras is constructed for discrete strings. • Spinor representation of discrete Frenet equations is developed.

  15. Benih Keturunan Induk Ikan Nila yang Divaksinasi pada Tingkat Kematangan Gonad-2 Lebih Tahan Terhadap Infeksi Streptococcus agalactiae (RESISTANCE OF TILAPIA (OREOCHRIMIS NILOTICUS) FRY VACCINATED AT DIFFERENT GONADAL DEVELOPMENTAL STAGES TOWARD STREPTOCO

    OpenAIRE

    Khairun Nissa; Sukenda Sukenda; Muhammad Zairin Junior; Angela Mariana Lusiastuti; Sri Nuryati

    2016-01-01

    The aim of this study was to evaluate the effectiveness of vaccination based on gonad maturationstages on tilapia brood stocks in which the released antibodies was able to be transferred to the seed.Vaccine composed with whole cells and extracellular product (ECP) was injected at stage 2 and stage 3 ofthe gonad development stages at concentration of 109 CFU mL1 as much as 4 mL to 1 kg of brood fish.Control fish was unvaccinated treatment. Challenge study at seed was conducted by immersing S. ...

  16. Principles of discrete time mechanics

    CERN Document Server

    Jaroszkiewicz, George

    2014-01-01

    Could time be discrete on some unimaginably small scale? Exploring the idea in depth, this unique introduction to discrete time mechanics systematically builds the theory up from scratch, beginning with the historical, physical and mathematical background to the chronon hypothesis. Covering classical and quantum discrete time mechanics, this book presents all the tools needed to formulate and develop applications of discrete time mechanics in a number of areas, including spreadsheet mechanics, classical and quantum register mechanics, and classical and quantum mechanics and field theories. A consistent emphasis on contextuality and the observer-system relationship is maintained throughout.

  17. Dark discrete gauge symmetries

    International Nuclear Information System (INIS)

    Batell, Brian

    2011-01-01

    We investigate scenarios in which dark matter is stabilized by an Abelian Z N discrete gauge symmetry. Models are surveyed according to symmetries and matter content. Multicomponent dark matter arises when N is not prime and Z N contains one or more subgroups. The dark sector interacts with the visible sector through the renormalizable kinetic mixing and Higgs portal operators, and we highlight the basic phenomenology in these scenarios. In particular, multiple species of dark matter can lead to an unconventional nuclear recoil spectrum in direct detection experiments, while the presence of new light states in the dark sector can dramatically affect the decays of the Higgs at the Tevatron and LHC, thus providing a window into the gauge origin of the stability of dark matter.

  18. Discrete anti-gravity

    International Nuclear Information System (INIS)

    Noyes, H.P.; Starson, S.

    1991-03-01

    Discrete physics, because it replaces time evolution generated by the energy operator with a global bit-string generator (program universe) and replaces ''fields'' with the relativistic Wheeler-Feynman ''action at a distance,'' allows the consistent formulation of the concept of signed gravitational charge for massive particles. The resulting prediction made by this version of the theory is that free anti-particles near the surface of the earth will ''fall'' up with the same acceleration that the corresponding particles fall down. So far as we can see, no current experimental information is in conflict with this prediction of our theory. The experiment crusis will be one of the anti-proton or anti-hydrogen experiments at CERN. Our prediction should be much easier to test than the small effects which those experiments are currently designed to detect or bound. 23 refs

  19. Emotional Aging: A Discrete Emotions Perspective

    Directory of Open Access Journals (Sweden)

    Ute eKunzmann

    2014-05-01

    Full Text Available Perhaps the most important single finding in the field of emotional aging has been that the overall quality of affective experience steadily improves during adulthood and can be maintained into old age. Recent lifespan developmental theories have provided motivation- and experience-based explanations for this phenomenon. These theories suggest that, as individuals grow older, they become increasingly motivated and able to regulate their emotions, which could result in reduced negativity and enhanced positivity. The objective of this paper is to expand existing theories and empirical research on emotional aging by presenting a discrete emotions perspective. To illustrate the usefulness of this approach, we focus on a discussion of the literature examining age differences in anger and sadness. These two negative emotions have been subsumed under the singular concept of negative affect. From a discrete emotions perspective, however, they are highly distinct. Sadness is elicited by an irreversible loss and associated with low situational control, high goal adjustment tendencies, and the motivation to search for social support. The experience of anger, by contrast, is typically triggered by other individuals who intentio

  20. Emotional aging: a discrete emotions perspective.

    Science.gov (United States)

    Kunzmann, Ute; Kappes, Cathleen; Wrosch, Carsten

    2014-01-01

    Perhaps the most important single finding in the field of emotional aging has been that the overall quality of affective experience steadily improves during adulthood and can be maintained into old age. Recent lifespan developmental theories have provided motivation- and experience-based explanations for this phenomenon. These theories suggest that, as individuals grow older, they become increasingly motivated and able to regulate their emotions, which could result in reduced negativity and enhanced positivity. The objective of this paper is to expand existing theories and empirical research on emotional aging by presenting a discrete emotions perspective. To illustrate the usefulness of this approach, we focus on a discussion of the literature examining age differences in anger and sadness. These two negative emotions have typically been subsumed under the singular concept of negative affect. From a discrete emotions perspective, however, they are highly distinct and show multidirectional age differences. We propose that such contrasting age differences in specific negative emotions have important implications for our understanding of long-term patterns of affective well-being across the adult lifespan.

  1. Development Stages and Curriculum: A Japanese Perspective.

    Science.gov (United States)

    Abiko, Tadahiko

    2002-01-01

    Discusses contemporary psychologists' criticism of Jean Piaget's developmental theory; reviews research in brain science, psychology, history, and the experiences of teachers; proposes a new theory of developmental stages based on children's shifting interests; discuses implications of "shifting interest center theory" for school…

  2. The Domain of Developmental Psychopathology.

    Science.gov (United States)

    Sroufe, L. Alan; Rutter, Michael

    1984-01-01

    Describes how developmental psychopathology differs from related disciplines, including abnormal psychology, psychiatry, clinical child psychology, and developmental psychology. Points out propositions underlying a developmental perspective and discusses implications for research in developmental psychopathology. (Author/RH)

  3. Combustion Stability Verification for the Thrust Chamber Assembly of J-2X Developmental Engines 10001, 10002, and 10003

    Science.gov (United States)

    Morgan, C. J.; Hulka, J. R.; Casiano, M. J.; Kenny, R. J.; Hinerman, T. D.; Scholten, N.

    2015-01-01

    The J-2X engine, a liquid oxygen/liquid hydrogen propellant rocket engine available for future use on the upper stage of the Space Launch System vehicle, has completed testing of three developmental engines at NASA Stennis Space Center. Twenty-one tests of engine E10001 were conducted from June 2011 through September 2012, thirteen tests of the engine E10002 were conducted from February 2013 through September 2013, and twelve tests of engine E10003 were conducted from November 2013 to April 2014. Verification of combustion stability of the thrust chamber assembly was conducted by perturbing each of the three developmental engines. The primary mechanism for combustion stability verification was examining the response caused by an artificial perturbation (bomb) in the main combustion chamber, i.e., dynamic combustion stability rating. No dynamic instabilities were observed in the TCA, although a few conditions were not bombed. Additional requirements, included to guard against spontaneous instability or rough combustion, were also investigated. Under certain conditions, discrete responses were observed in the dynamic pressure data. The discrete responses were of low amplitude and posed minimal risk to safe engine operability. Rough combustion analyses showed that all three engines met requirements for broad-banded frequency oscillations. Start and shutdown transient chug oscillations were also examined to assess the overall stability characteristics, with no major issues observed.

  4. Developmental ecology of the American horseshoe crab Limulus polyphemus

    Directory of Open Access Journals (Sweden)

    Mark L. BOTTON, Richard A. TANKERSLEY, Robert E. LOVELAND

    2010-10-01

    Full Text Available During spawning events, horseshoe crab eggs are released from the female’s oviducts, and fertilized by one or more males. Eggs are shaped by the female into discrete clutches deposited in nests at depths of 10-20 cm on intertidal estuarine beaches. Distinguishing between fresh eggs and the early developmental stages is obfuscated by the large amount of dense, opaque yolk. The first unambiguous confirmation of development is the formation of the rudimentary prosomatic appendages at the “limb bud” stage. Several days thereafter, the outer chorion is shed and the developing embryo expands and undergoes a series of molts within the clear inner egg membrane. The trilobite (first instar stage thus attained may remain within the beach sediments for several more weeks, until hatching is facilitated by environmental factors such as hydration, agitation, and osmotic shock that accompany the infiltration of seawater into the nests. Trilobites exhibit endogenous circatidal swimming rhythms that are entrained by mechanical agitation, suggesting that peaks in larval swimming are timed to coincide with periods of high water and the inundation of the nests. Larval swimming is limited and does not appear to result in long-distance dispersal. The limited dispersal of the larvae has important implications for the population dynamics of relatively isolated populations. The rate of larval development is highly plastic and is influenced by temperature, salinity, dissolved oxygen, and the presence of pollutants. The broad environmental tolerances of horseshoe crab embryos and larvae are important in understanding their current geographic distribution and their evolutionary persistence [Current Zoology 56 (5: 550–562, 2010].

  5. Control of Discrete Event Systems

    NARCIS (Netherlands)

    Smedinga, Rein

    1989-01-01

    Systemen met discrete gebeurtenissen spelen in vele gebieden een rol. In dit proefschrift staat de volgorde van gebeurtenissen centraal en worden tijdsaspecten buiten beschouwing gelaten. In dat geval kunnen systemen met discrete gebeurtenissen goed worden gemodelleerd door gebruik te maken van

  6. Discrete Mathematics and Its Applications

    Science.gov (United States)

    Oxley, Alan

    2010-01-01

    The article gives ideas that lecturers of undergraduate Discrete Mathematics courses can use in order to make the subject more interesting for students and encourage them to undertake further studies in the subject. It is possible to teach Discrete Mathematics with little or no reference to computing. However, students are more likely to be…

  7. Discrete Mathematics and Curriculum Reform.

    Science.gov (United States)

    Kenney, Margaret J.

    1996-01-01

    Defines discrete mathematics as the mathematics necessary to effect reasoned decision making in finite situations and explains how its use supports the current view of mathematics education. Discrete mathematics can be used by curriculum developers to improve the curriculum for students of all ages and abilities. (SLD)

  8. Connections on discrete fibre bundles

    International Nuclear Information System (INIS)

    Manton, N.S.; Cambridge Univ.

    1987-01-01

    A new approach to gauge fields on a discrete space-time is proposed, in which the fundamental object is a discrete version of a principal fibre bundle. If the bundle is twisted, the gauge fields are topologically non-trivial automatically. (orig.)

  9. An essay on discrete foundations for physics

    International Nuclear Information System (INIS)

    Noyes, H.P.; McGoveran, D.O.

    1988-07-01

    We base our theory of physics and cosmology on the five principles of finiteness, discreteness, finite computability, absolute non-uniqueness, and strict construction. Our modeling methodology starts from the current practice of physics, constructs a self-consistent representation based on the ordering operator calculus and provides rules of correspondence that allow us to test the theory by experiment. We use program universe to construct a growing collection of bit strings whose initial portions (labels) provide the quantum numbers that are conserved in the events defined by the construction. The labels are followed by content strings which are used to construct event-based finite and discrete coordinates. On general grounds such a theory has a limiting velocity, and positions and velocities do not commute. We therefore reconcile quantum mechanics with relativity at an appropriately fundamental stage in the construction. We show that events in different coordinate systems are connected by the appropriate finite and discrete version of the Lorentz transformation, that 3-momentum is conserved in events, and that this conservation law is the same as the requirement that different paths can ''interfere'' only when they differ by an integral number of deBroglie wavelengths. 38 refs., 12 figs., 3 tabs

  10. An essay on discrete foundations for physics

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, H.P.; McGoveran, D.O.

    1988-07-01

    We base our theory of physics and cosmology on the five principles of finiteness, discreteness, finite computability, absolute non-uniqueness, and strict construction. Our modeling methodology starts from the current practice of physics, constructs a self-consistent representation based on the ordering operator calculus and provides rules of correspondence that allow us to test the theory by experiment. We use program universe to construct a growing collection of bit strings whose initial portions (labels) provide the quantum numbers that are conserved in the events defined by the construction. The labels are followed by content strings which are used to construct event-based finite and discrete coordinates. On general grounds such a theory has a limiting velocity, and positions and velocities do not commute. We therefore reconcile quantum mechanics with relativity at an appropriately fundamental stage in the construction. We show that events in different coordinate systems are connected by the appropriate finite and discrete version of the Lorentz transformation, that 3-momentum is conserved in events, and that this conservation law is the same as the requirement that different paths can ''interfere'' only when they differ by an integral number of deBroglie wavelengths. 38 refs., 12 figs., 3 tabs.

  11. An essay on discrete foundations for physics

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, H.P.; McGoveran, D.O.

    1988-10-05

    We base our theory of physics and cosmology on the five principles of finiteness, discreteness, finite computability, absolute non- uniqueness, and strict construction. Our modeling methodology starts from the current practice of physics, constructs a self-consistent representation based on the ordering operator calculus and provides rules of correspondence that allow us to test the theory by experiment. We use program universe to construct a growing collection of bit strings whose initial portions (labels) provide the quantum numbers that are conserved in the events defined by the construction. The labels are followed by content strings which are used to construct event-based finite and discrete coordinates. On general grounds such a theory has a limiting velocity, and positions and velocities do not commute. We therefore reconcile quantum mechanics with relativity at an appropriately fundamental stage in the construction. We show that events in different coordinate systems are connected by the appropriate finite and discrete version of the Lorentz transformation, that 3-momentum is conserved in events, and that this conservation law is the same as the requirement that different paths can ''interfere'' only when they differ by an integral number of deBroglie wavelengths. 38 refs., 12 figs., 3 tabs.

  12. An essay on discrete foundations for physics

    International Nuclear Information System (INIS)

    Noyes, H.P.; McGoveran, D.O.

    1988-01-01

    We base our theory of physics and cosmology on the five principles of finiteness, discreteness, finite computability, absolute non- uniqueness, and strict construction. Our modeling methodology starts from the current practice of physics, constructs a self-consistent representation based on the ordering operator calculus and provides rules of correspondence that allow us to test the theory by experiment. We use program universe to construct a growing collection of bit strings whose initial portions (labels) provide the quantum numbers that are conserved in the events defined by the construction. The labels are followed by content strings which are used to construct event-based finite and discrete coordinates. On general grounds such a theory has a limiting velocity, and positions and velocities do not commute. We therefore reconcile quantum mechanics with relativity at an appropriately fundamental stage in the construction. We show that events in different coordinate systems are connected by the appropriate finite and discrete version of the Lorentz transformation, that 3-momentum is conserved in events, and that this conservation law is the same as the requirement that different paths can ''interfere'' only when they differ by an integral number of deBroglie wavelengths. 38 refs., 12 figs., 3 tabs

  13. The Discrete Emotions Questionnaire: A New Tool for Measuring State Self-Reported Emotions.

    Science.gov (United States)

    Harmon-Jones, Cindy; Bastian, Brock; Harmon-Jones, Eddie

    2016-01-01

    Several discrete emotions have broad theoretical and empirical importance, as shown by converging evidence from diverse areas of psychology, including facial displays, developmental behaviors, and neuroscience. However, the measurement of these states has not progressed along with theory, such that when researchers measure subjectively experienced emotions, they commonly rely on scales assessing broad dimensions of affect (positivity and negativity), rather than discrete emotions. The current manuscript presents four studies that validate a new instrument, the Discrete Emotions Questionnaire (DEQ), that is sensitive to eight distinct state emotions: anger, disgust, fear, anxiety, sadness, happiness, relaxation, and desire. Emotion theory supporting the importance of distinguishing these specific emotions is reviewed.

  14. Discrete dynamics versus analytic dynamics

    DEFF Research Database (Denmark)

    Toxværd, Søren

    2014-01-01

    For discrete classical Molecular dynamics obtained by the “Verlet” algorithm (VA) with the time increment h there exists a shadow Hamiltonian H˜ with energy E˜(h) , for which the discrete particle positions lie on the analytic trajectories for H˜ . Here, we proof that there, independent...... of such an analytic analogy, exists an exact hidden energy invariance E * for VA dynamics. The fact that the discrete VA dynamics has the same invariances as Newtonian dynamics raises the question, which of the formulations that are correct, or alternatively, the most appropriate formulation of classical dynamics....... In this context the relation between the discrete VA dynamics and the (general) discrete dynamics investigated by Lee [Phys. Lett. B122, 217 (1983)] is presented and discussed....

  15. Modern approaches to discrete curvature

    CERN Document Server

    Romon, Pascal

    2017-01-01

     This book provides a valuable glimpse into discrete curvature, a rich new field of research which blends discrete mathematics, differential geometry, probability and computer graphics. It includes a vast collection of ideas and tools which will offer something new to all interested readers. Discrete geometry has arisen as much as a theoretical development as in response to unforeseen challenges coming from applications. Discrete and continuous geometries have turned out to be intimately connected. Discrete curvature is the key concept connecting them through many bridges in numerous fields: metric spaces, Riemannian and Euclidean geometries, geometric measure theory, topology, partial differential equations, calculus of variations, gradient flows, asymptotic analysis, probability, harmonic analysis, graph theory, etc. In spite of its crucial importance both in theoretical mathematics and in applications, up to now, almost no books have provided a coherent outlook on this emerging field.

  16. Use of drawings in children with pervasive developmental disorder during hospitalization: a developmental perspective.

    Science.gov (United States)

    Stefanatou, Athena

    2008-12-01

    The level and nature of emotional upheaval and relationship to developmental stage was studied in children with pervasive developmental disorder (PDD) hospitalized for head injury. The sample consisted of 25 hospitalized children aged 5-12 years. Children were asked to make the drawing of a ;person in hospital'. The drawings were evaluated by Koppitz's emotional indicators. Punishment and persecution were the main cognitive constructs of children in order to explain hospitalization.

  17. Genome Transfer Prevents Fragmentation and Restores Developmental Potential of Developmentally Compromised Postovulatory Aged Mouse Oocytes

    Directory of Open Access Journals (Sweden)

    Mitsutoshi Yamada

    2017-03-01

    Full Text Available Changes in oocyte quality can have great impact on the developmental potential of early embryos. Here we test whether nuclear genome transfer from a developmentally incompetent to a developmentally competent oocyte can restore developmental potential. Using in vitro oocyte aging as a model system we performed nuclear transfer in mouse oocytes at metaphase II or at the first interphase, and observed that development to the blastocyst stage and to term was as efficient as in control embryos. The increased developmental potential is explained primarily by correction of abnormal cytokinesis at anaphase of meiosis and mitosis, by a reduction in chromosome segregation errors, and by normalization of the localization of chromosome passenger complex components survivin and cyclin B1. These observations demonstrate that developmental decline is primarily due to abnormal function of cytoplasmic factors involved in cytokinesis, while the genome remains developmentally fully competent.

  18. A Developmental Model Applied to Problems of Deafness.

    Science.gov (United States)

    Schlesinger, Hilde S.

    2000-01-01

    This "classic" article (1972) in the field of deaf studies includes some interpretive notes for current readers. The article examines the effect of deafness on basic developmental tasks at each of the eight developmental stages of Erik Erikson's theory of psychosocial development and explains the more successful passage through these…

  19. Discretion and Disproportionality

    Directory of Open Access Journals (Sweden)

    Jason A. Grissom

    2015-12-01

    Full Text Available Students of color are underrepresented in gifted programs relative to White students, but the reasons for this underrepresentation are poorly understood. We investigate the predictors of gifted assignment using nationally representative, longitudinal data on elementary students. We document that even among students with high standardized test scores, Black students are less likely to be assigned to gifted services in both math and reading, a pattern that persists when controlling for other background factors, such as health and socioeconomic status, and characteristics of classrooms and schools. We then investigate the role of teacher discretion, leveraging research from political science suggesting that clients of government services from traditionally underrepresented groups benefit from diversity in the providers of those services, including teachers. Even after conditioning on test scores and other factors, Black students indeed are referred to gifted programs, particularly in reading, at significantly lower rates when taught by non-Black teachers, a concerning result given the relatively low incidence of assignment to own-race teachers among Black students.

  20. Discrete Planck spectra

    International Nuclear Information System (INIS)

    Vlad, Valentin I.; Ionescu-Pallas, Nicholas

    2000-10-01

    The Planck radiation spectrum of ideal cubic and spherical cavities, in the region of small adiabatic invariance, γ = TV 1/3 , is shown to be discrete and strongly dependent on the cavity geometry and temperature. This behavior is the consequence of the random distribution of the state weights in the cubic cavity and of the random overlapping of the successive multiplet components, for the spherical cavity. The total energy (obtained by summing up the exact contributions of the eigenvalues and their weights, for low values of the adiabatic invariance) does not obey any longer Stefan-Boltzmann law. The new law includes a corrective factor depending on γ and imposes a faster decrease of the total energy to zero, for γ → 0. We have defined the double quantized regime both for cubic and spherical cavities by the superior and inferior limits put on the principal quantum numbers or the adiabatic invariance. The total energy of the double quantized cavities shows large differences from the classical calculations over unexpected large intervals, which are measurable and put in evidence important macroscopic quantum effects. (author)

  1. Some extensions of the discrete lotsizing and scheduling problem

    NARCIS (Netherlands)

    M. Salomon (Marc); L.G. Kroon (Leo); R. Kuik (Roelof); L.N. van Wassenhove (Luk)

    1991-01-01

    textabstractIn this paper the Discrete Lotsizing and Scheduling Problem (DLSP) is considered. DLSP relates to capacitated lotsizing as well as to job scheduling problems and is concerned with determining a feasible production schedule with minimal total costs in a single-stage manufacturing process.

  2. Integrating and Analyzing Psychosocial and Stage Theories To Challenge the Development of the Injured Collegiate Athlete.

    Science.gov (United States)

    Harris, Laura L.

    2003-01-01

    Integrated a psychosocial developmental theory (the Kubler-Ross Stage Theory) and a psychological stage theory (the Ross Stage Theory) and a psychological stage theory (the Chickering and Reisser psychosocial and developmental theory) for challenging injured collegiate student-athletes' personal development. A search of online databases from…

  3. Perfect discretization of path integrals

    International Nuclear Information System (INIS)

    Steinhaus, Sebastian

    2012-01-01

    In order to obtain a well-defined path integral one often employs discretizations. In the case of General Relativity these generically break diffeomorphism symmetry, which has severe consequences since these symmetries determine the dynamics of the corresponding system. In this article we consider the path integral of reparametrization invariant systems as a toy example and present an improvement procedure for the discretized propagator. Fixed points and convergence of the procedure are discussed. Furthermore we show that a reparametrization invariant path integral implies discretization independence and acts as a projector onto physical states.

  4. Perfect discretization of path integrals

    Science.gov (United States)

    Steinhaus, Sebastian

    2012-05-01

    In order to obtain a well-defined path integral one often employs discretizations. In the case of General Relativity these generically break diffeomorphism symmetry, which has severe consequences since these symmetries determine the dynamics of the corresponding system. In this article we consider the path integral of reparametrization invariant systems as a toy example and present an improvement procedure for the discretized propagator. Fixed points and convergence of the procedure are discussed. Furthermore we show that a reparametrization invariant path integral implies discretization independence and acts as a projector onto physical states.

  5. The origin of discrete particles

    CERN Document Server

    Bastin, T

    2009-01-01

    This book is a unique summary of the results of a long research project undertaken by the authors on discreteness in modern physics. In contrast with the usual expectation that discreteness is the result of mathematical tools for insertion into a continuous theory, this more basic treatment builds up the world from the discrimination of discrete entities. This gives an algebraic structure in which certain fixed numbers arise. As such, one agrees with the measured value of the fine-structure constant to one part in 10,000,000 (10 7 ). Sample Chapter(s). Foreword (56 KB). Chapter 1: Introduction

  6. Developmental transcriptome of Aplysia californica'

    KAUST Repository

    Heyland, Andreas

    2010-12-06

    Genome-wide transcriptional changes in development provide important insight into mechanisms underlying growth, differentiation, and patterning. However, such large-scale developmental studies have been limited to a few representatives of Ecdysozoans and Chordates. Here, we characterize transcriptomes of embryonic, larval, and metamorphic development in the marine mollusc Aplysia californica and reveal novel molecular components associated with life history transitions. Specifically, we identify more than 20 signal peptides, putative hormones, and transcription factors in association with early development and metamorphic stages-many of which seem to be evolutionarily conserved elements of signal transduction pathways. We also characterize genes related to biomineralization-a critical process of molluscan development. In summary, our experiment provides the first large-scale survey of gene expression in mollusc development, and complements previous studies on the regulatory mechanisms underlying body plan patterning and the formation of larval and juvenile structures. This study serves as a resource for further functional annotation of transcripts and genes in Aplysia, specifically and molluscs in general. A comparison of the Aplysia developmental transcriptome with similar studies in the zebra fish Danio rerio, the fruit fly Drosophila melanogaster, the nematode Caenorhabditis elegans, and other studies on molluscs suggests an overall highly divergent pattern of gene regulatory mechanisms that are likely a consequence of the different developmental modes of these organisms. © 2010 Wiley-Liss, Inc., A Wiley Company.

  7. Synchronization Techniques in Parallel Discrete Event Simulation

    OpenAIRE

    Lindén, Jonatan

    2018-01-01

    Discrete event simulation is an important tool for evaluating system models in many fields of science and engineering. To improve the performance of large-scale discrete event simulations, several techniques to parallelize discrete event simulation have been developed. In parallel discrete event simulation, the work of a single discrete event simulation is distributed over multiple processing elements. A key challenge in parallel discrete event simulation is to ensure that causally dependent ...

  8. 3-D Discrete Analytical Ridgelet Transform

    OpenAIRE

    Helbert , David; Carré , Philippe; Andrès , Éric

    2006-01-01

    International audience; In this paper, we propose an implementation of the 3-D Ridgelet transform: the 3-D discrete analytical Ridgelet transform (3-D DART). This transform uses the Fourier strategy for the computation of the associated 3-D discrete Radon transform. The innovative step is the definition of a discrete 3-D transform with the discrete analytical geometry theory by the construction of 3-D discrete analytical lines in the Fourier domain. We propose two types of 3-D discrete lines:...

  9. Reproductive and developmental toxicology

    National Research Council Canada - National Science Library

    Gupta, Ramesh C

    2011-01-01

    .... Reproductive and Developmental Toxicology is a comprehensive and authoritative resource providing the latest literature enriched with relevant references describing every aspect of this area of science...

  10. Exact analysis of discrete data

    CERN Document Server

    Hirji, Karim F

    2005-01-01

    Researchers in fields ranging from biology and medicine to the social sciences, law, and economics regularly encounter variables that are discrete or categorical in nature. While there is no dearth of books on the analysis and interpretation of such data, these generally focus on large sample methods. When sample sizes are not large or the data are otherwise sparse, exact methods--methods not based on asymptotic theory--are more accurate and therefore preferable.This book introduces the statistical theory, analysis methods, and computation techniques for exact analysis of discrete data. After reviewing the relevant discrete distributions, the author develops the exact methods from the ground up in a conceptually integrated manner. The topics covered range from univariate discrete data analysis, a single and several 2 x 2 tables, a single and several 2 x K tables, incidence density and inverse sampling designs, unmatched and matched case -control studies, paired binary and trinomial response models, and Markov...

  11. Discrete geometric structures for architecture

    KAUST Repository

    Pottmann, Helmut

    2010-01-01

    . The talk will provide an overview of recent progress in this field, with a particular focus on discrete geometric structures. Most of these result from practical requirements on segmenting a freeform shape into planar panels and on the physical realization

  12. Causal Dynamics of Discrete Surfaces

    Directory of Open Access Journals (Sweden)

    Pablo Arrighi

    2014-03-01

    Full Text Available We formalize the intuitive idea of a labelled discrete surface which evolves in time, subject to two natural constraints: the evolution does not propagate information too fast; and it acts everywhere the same.

  13. Perfect discretization of path integrals

    OpenAIRE

    Steinhaus, Sebastian

    2011-01-01

    In order to obtain a well-defined path integral one often employs discretizations. In the case of General Relativity these generically break diffeomorphism symmetry, which has severe consequences since these symmetries determine the dynamics of the corresponding system. In this article we consider the path integral of reparametrization invariant systems as a toy example and present an improvement procedure for the discretized propagator. Fixed points and convergence of the procedure are discu...

  14. Stage design

    International Nuclear Information System (INIS)

    Shacter, J.

    1975-01-01

    A method is described of cycling gases through a plurality of diffusion stages comprising the steps of admitting the diffused gases from a first diffusion stage into an axial compressor, simultaneously admitting the undiffused gases from a second diffusion stage into an intermediate pressure zone of said compressor corresponding in pressure to the pressure of said undiffused gases, and then admitting the resulting compressed mixture of diffused and undiffused gases into a third diffusion stage

  15. Applied discrete-time queues

    CERN Document Server

    Alfa, Attahiru S

    2016-01-01

    This book introduces the theoretical fundamentals for modeling queues in discrete-time, and the basic procedures for developing queuing models in discrete-time. There is a focus on applications in modern telecommunication systems. It presents how most queueing models in discrete-time can be set up as discrete-time Markov chains. Techniques such as matrix-analytic methods (MAM) that can used to analyze the resulting Markov chains are included. This book covers single node systems, tandem system and queueing networks. It shows how queues with time-varying parameters can be analyzed, and illustrates numerical issues associated with computations for the discrete-time queueing systems. Optimal control of queues is also covered. Applied Discrete-Time Queues targets researchers, advanced-level students and analysts in the field of telecommunication networks. It is suitable as a reference book and can also be used as a secondary text book in computer engineering and computer science. Examples and exercises are includ...

  16. Staging Mobilities

    DEFF Research Database (Denmark)

    Jensen, Ole B.

    and lived as people are “staging themselves” (from below). Staging mobilities is a dynamic process between “being staged” (for example, being stopped at traffic lights) and the “mobile staging” of interacting individuals (negotiating a passage on the pavement). Staging Mobilities is about the fact...

  17. Screening of the ‘Open Scaffolds’ collection from Compounds Australia identifies a new chemical entity with anthelmintic activities against different developmental stages of the barber's pole worm and other parasitic nematodes

    Directory of Open Access Journals (Sweden)

    Sarah Preston

    2017-12-01

    Full Text Available The discovery and development of novel anthelmintic classes is essential to sustain the control of socioeconomically important parasitic worms of humans and animals. With the aim of offering novel, lead-like scaffolds for drug discovery, Compounds Australia released the ‘Open Scaffolds’ collection containing 33,999 compounds, with extensive information available on the physicochemical properties of these chemicals. In the present study, we screened 14,464 prioritised compounds from the ‘Open Scaffolds’ collection against the exsheathed third-stage larvae (xL3s of Haemonchus contortus using recently developed whole-organism screening assays. We identified a hit compound, called SN00797439, which was shown to reproducibly reduce xL3 motility by ≥ 70%; this compound induced a characteristic, “coiled” xL3 phenotype (IC50 = 3.46–5.93 μM, inhibited motility of fourth-stage larvae (L4s; IC50 = 0.31–12.5 μM and caused considerable cuticular damage to L4s in vitro. When tested on other parasitic nematodes in vitro, SN00797439 was shown to inhibit (IC50 = 3–50 μM adults of Ancylostoma ceylanicum (hookworm and first-stage larvae of Trichuris muris (whipworm and eventually kill (>90% these stages. Furthermore, this compound completely inhibited the motility of female and male adults of Brugia malayi (50–100 μM as well as microfilariae of both B. malayi and Dirofilaria immitis (heartworm. Overall, these results show that SN00797439 acts against genetically (evolutionarily distant parasitic nematodes i.e. H. contortus and A. ceylanicum [strongyloids] vs. B. malayi and D. immitis [filarioids] vs. T. muris [enoplid], and, thus, might offer a novel, lead-like scaffold for the development of a relatively broad-spectrum anthelmintic. Our future work will focus on assessing the activity of SN00797439 against other pathogens that cause neglected tropical diseases, optimising analogs with improved biological activities and

  18. Developmental constraint of insect audition

    Directory of Open Access Journals (Sweden)

    Strauß Johannes

    2006-12-01

    Full Text Available Abstract Background Insect ears contain very different numbers of sensory cells, from only one sensory cell in some moths to thousands of sensory cells, e.g. in cicadas. These differences still await functional explanation and especially the large numbers in cicadas remain puzzling. Insects of the different orders have distinct developmental sequences for the generation of auditory organs. These sensory cells might have different functions depending on the developmental stages. Here we propose that constraints arising during development are also important for the design of insect ears and might influence cell numbers of the adults. Presentation of the hypothesis We propose that the functional requirements of the subadult stages determine the adult complement of sensory units in the auditory system of cicadas. The hypothetical larval sensory organ should function as a vibration receiver, representing a functional caenogenesis. Testing the hypothesis Experiments at different levels have to be designed to test the hypothesis. Firstly, the neuroanatomy of the larval sense organ should be analyzed to detail. Secondly, the function should be unraveled neurophysiologically and behaviorally. Thirdly, the persistence of the sensory cells and the rebuilding of the sensory organ to the adult should be investigated. Implications of the hypothesis Usually, the evolution of insect ears is viewed with respect to physiological and neuronal mechanisms of sound perception. This view should be extended to the development of sense organs. Functional requirements during postembryonic development may act as constraints for the evolution of adult organs, as exemplified with the auditory system of cicadas.

  19. Discrete Curvature Theories and Applications

    KAUST Repository

    Sun, Xiang

    2016-08-25

    Discrete Di erential Geometry (DDG) concerns discrete counterparts of notions and methods in di erential geometry. This thesis deals with a core subject in DDG, discrete curvature theories on various types of polyhedral surfaces that are practically important for free-form architecture, sunlight-redirecting shading systems, and face recognition. Modeled as polyhedral surfaces, the shapes of free-form structures may have to satisfy di erent geometric or physical constraints. We study a combination of geometry and physics { the discrete surfaces that can stand on their own, as well as having proper shapes for the manufacture. These proper shapes, known as circular and conical meshes, are closely related to discrete principal curvatures. We study curvature theories that make such surfaces possible. Shading systems of freeform building skins are new types of energy-saving structures that can re-direct the sunlight. From these systems, discrete line congruences across polyhedral surfaces can be abstracted. We develop a new curvature theory for polyhedral surfaces equipped with normal congruences { a particular type of congruences de ned by linear interpolation of vertex normals. The main results are a discussion of various de nitions of normality, a detailed study of the geometry of such congruences, and a concept of curvatures and shape operators associated with the faces of a triangle mesh. These curvatures are compatible with both normal congruences and the Steiner formula. In addition to architecture, we consider the role of discrete curvatures in face recognition. We use geometric measure theory to introduce the notion of asymptotic cones associated with a singular subspace of a Riemannian manifold, which is an extension of the classical notion of asymptotic directions. We get a simple expression of these cones for polyhedral surfaces, as well as convergence and approximation theorems. We use the asymptotic cones as facial descriptors and demonstrate the

  20. Analysis of Discrete Mittag - Leffler Functions

    Directory of Open Access Journals (Sweden)

    N. Shobanadevi

    2015-03-01

    Full Text Available Discrete Mittag - Leffler functions play a major role in the development of the theory of discrete fractional calculus. In the present article, we analyze qualitative properties of discrete Mittag - Leffler functions and establish sufficient conditions for convergence, oscillation and summability of the infinite series associated with discrete Mittag - Leffler functions.

  1. Foundations of a discrete physics

    International Nuclear Information System (INIS)

    McGoveran, D.; Noyes, P.

    1988-01-01

    Starting from the principles of finiteness, discreteness, finite computability and absolute nonuniqueness, we develop the ordering operator calculus, a strictly constructive mathematical system having the empirical properties required by quantum mechanical and special relativistic phenomena. We show how to construct discrete distance functions, and both rectangular and spherical coordinate systems(with a discrete version of ''π''). The richest discrete space constructible without a preferred axis and preserving translational and rotational invariance is shown to be a discrete 3-space with the usual symmetries. We introduce a local ordering parameter with local (proper) time-like properties and universal ordering parameters with global (cosmological) time-like properties. Constructed ''attribute velocities'' connect ensembles with attributes that are invariant as the appropriate time-like parameter increases. For each such attribute, we show how to construct attribute velocities which must satisfy the '' relativistic Doppler shift'' and the ''relativistic velocity composition law,'' as well as the Lorentz transformations. By construction, these velocities have finite maximum and minimum values. In the space of all attributes, the minimum of these maximum velocities will predominate in all multiple attribute computations, and hence can be identified as a fundamental limiting velocity, General commutation relations are constructed which under the physical interpretation are shown to reduce to the usual quantum mechanical commutation relations. 50 refs., 18 figs

  2. Trading stages

    DEFF Research Database (Denmark)

    Steiner, Uli; Tuljapurkar, Shripad; Coulson, Tim

    2012-01-01

    Interest in stage-and age structured models has recently increased because they can describe quantitative traits such as size that are left out of age-only demography. Available methods for the analysis of effects of vital rates on lifespan in stage-structured models have not been widely applied ...... examples. Much of our approach relies on trading of time and mortality risk in one stage for time and risk in others. Our approach contributes to the new framework of the study of age- and stage-structured biodemography....

  3. Discrete differential geometry. Consistency as integrability

    OpenAIRE

    Bobenko, Alexander I.; Suris, Yuri B.

    2005-01-01

    A new field of discrete differential geometry is presently emerging on the border between differential and discrete geometry. Whereas classical differential geometry investigates smooth geometric shapes (such as surfaces), and discrete geometry studies geometric shapes with finite number of elements (such as polyhedra), the discrete differential geometry aims at the development of discrete equivalents of notions and methods of smooth surface theory. Current interest in this field derives not ...

  4. Integrable structure in discrete shell membrane theory.

    Science.gov (United States)

    Schief, W K

    2014-05-08

    We present natural discrete analogues of two integrable classes of shell membranes. By construction, these discrete shell membranes are in equilibrium with respect to suitably chosen internal stresses and external forces. The integrability of the underlying equilibrium equations is proved by relating the geometry of the discrete shell membranes to discrete O surface theory. We establish connections with generalized barycentric coordinates and nine-point centres and identify a discrete version of the classical Gauss equation of surface theory.

  5. Degree distribution in discrete case

    International Nuclear Information System (INIS)

    Wang, Li-Na; Chen, Bin; Yan, Zai-Zai

    2011-01-01

    Vertex degree of many network models and real-life networks is limited to non-negative integer. By means of measure and integral, the relation of the degree distribution and the cumulative degree distribution in discrete case is analyzed. The degree distribution, obtained by the differential of its cumulative, is only suitable for continuous case or discrete case with constant degree change. When degree change is not a constant but proportional to degree itself, power-law degree distribution and its cumulative have the same exponent and the mean value is finite for power-law exponent greater than 1. -- Highlights: → Degree change is the crux for using the cumulative degree distribution method. → It suits for discrete case with constant degree change. → If degree change is proportional to degree, power-law degree distribution and its cumulative have the same exponent. → In addition, the mean value is finite for power-law exponent greater than 1.

  6. A new system for assessment of growth using mandibular canine calcification stages and its correlation with modified MP3 stages.

    Science.gov (United States)

    Hegde, Gautham; Hegde, Nanditha; Kumar, Anil; Keshavaraj

    2014-07-01

    Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. A total of 160 periapical radiographs, of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian's stages of dental calcification and the modified MP3 stages. The correlation coefficient between MP3 stages and developmental stages of mandibular canine was found to be significant in both male and female groups. When the canine calcification stages were compared with the MP3 stages it was found that with the exception of the D stage of canine calcification the remaining stages showed a very high correlation with the modified MP3 stages. The correlation between the mandibular canine calcification stages, and the MP3 stages was found to be significant. The canine calcification could be used as a sole indicator for assessment of skeletal maturity.

  7. On the discrete Gabor transform and the discrete Zak transform

    NARCIS (Netherlands)

    Bastiaans, M.J.; Geilen, M.C.W.

    1996-01-01

    Gabor's expansion of a discrete-time signal into a set of shifted and modulated versions of an elementary signal (or synthesis window) and the inverse operation -- the Gabor transform -- with which Gabor's expansion coefficients can be determined, are introduced. It is shown how, in the case of a

  8. Discrete Choice and Rational Inattention

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Melo, Emerson; de Palma, André

    2017-01-01

    This paper establishes a general equivalence between discrete choice and rational inattention models. Matejka and McKay (2015, AER) showed that when information costs are modelled using the Shannon entropy, the result- ing choice probabilities in the rational inattention model take the multinomial...... logit form. We show that when information costs are modelled using a class of generalized entropies, then the choice probabilities in any rational inattention model are observationally equivalent to some additive random utility discrete choice model and vice versa. This equivalence arises from convex...

  9. Attachment in Middle Childhood: An Evolutionary-Developmental Perspective

    Science.gov (United States)

    Del Giudice, Marco

    2015-01-01

    Middle childhood is a key transitional stage in the development of attachment processes and representations. Here I discuss the middle childhood transition from an evolutionary-developmental perspective and show how this approach offers fresh insight into the function and organization of attachment in this life stage. I begin by presenting an…

  10. Quasicanonical structure of optimal control in constrained discrete systems

    Science.gov (United States)

    Sieniutycz, S.

    2003-06-01

    This paper considers discrete processes governed by difference rather than differential equations for the state transformation. The basic question asked is if and when Hamiltonian canonical structures are possible in optimal discrete systems. Considering constrained discrete control, general optimization algorithms are derived that constitute suitable theoretical and computational tools when evaluating extremum properties of constrained physical models. The mathematical basis of the general theory is the Bellman method of dynamic programming (DP) and its extension in the form of the so-called Carathéodory-Boltyanski (CB) stage criterion which allows a variation of the terminal state that is otherwise fixed in the Bellman's method. Two relatively unknown, powerful optimization algorithms are obtained: an unconventional discrete formalism of optimization based on a Hamiltonian for multistage systems with unconstrained intervals of holdup time, and the time interval constrained extension of the formalism. These results are general; namely, one arrives at: the discrete canonical Hamilton equations, maximum principles, and (at the continuous limit of processes with free intervals of time) the classical Hamilton-Jacobi theory along with all basic results of variational calculus. Vast spectrum of applications of the theory is briefly discussed.

  11. Developmental coordination disorder

    Science.gov (United States)

    Developmental coordination disorder can lead to: Learning problems Low self-esteem resulting from poor ability at sports and teasing by other children Repeated injuries Weight gain as a result of not wanting to participate ...

  12. Facts about Developmental Disabilities

    Science.gov (United States)

    ... play, learn, speak, behave, and move (for example, crawling and walking). Children develop at their own pace, ... person’s lifetime. Most developmental disabilities begin before a baby is born, but some can happen after birth ...

  13. Life Span Developmental Approach

    OpenAIRE

    Ali Eryilmaz

    2011-01-01

    The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of...

  14. Discrete Hamiltonian evolution and quantum gravity

    International Nuclear Information System (INIS)

    Husain, Viqar; Winkler, Oliver

    2004-01-01

    We study constrained Hamiltonian systems by utilizing general forms of time discretization. We show that for explicit discretizations, the requirement of preserving the canonical Poisson bracket under discrete evolution imposes strong conditions on both allowable discretizations and Hamiltonians. These conditions permit time discretizations for a limited class of Hamiltonians, which does not include homogeneous cosmological models. We also present two general classes of implicit discretizations which preserve Poisson brackets for any Hamiltonian. Both types of discretizations generically do not preserve first class constraint algebras. Using this observation, we show that time discretization provides a complicated time gauge fixing for quantum gravity models, which may be compared with the alternative procedure of gauge fixing before discretization

  15. Discrete exterior calculus discretization of incompressible Navier–Stokes equations over surface simplicial meshes

    KAUST Repository

    Mohamed, Mamdouh S.; Hirani, Anil N.; Samtaney, Ravi

    2016-01-01

    A conservative discretization of incompressible Navier–Stokes equations is developed based on discrete exterior calculus (DEC). A distinguishing feature of our method is the use of an algebraic discretization of the interior product operator and a

  16. Solving discrete zero point problems

    NARCIS (Netherlands)

    van der Laan, G.; Talman, A.J.J.; Yang, Z.F.

    2004-01-01

    In this paper an algorithm is proposed to .nd a discrete zero point of a function on the collection of integral points in the n-dimensional Euclidean space IRn.Starting with a given integral point, the algorithm generates a .nite sequence of adjacent integral simplices of varying dimension and

  17. Succinct Sampling from Discrete Distributions

    DEFF Research Database (Denmark)

    Bringmann, Karl; Larsen, Kasper Green

    2013-01-01

    We revisit the classic problem of sampling from a discrete distribution: Given n non-negative w-bit integers x_1,...,x_n, the task is to build a data structure that allows sampling i with probability proportional to x_i. The classic solution is Walker's alias method that takes, when implemented...

  18. Symplectomorphisms and discrete braid invariants

    NARCIS (Netherlands)

    Czechowski, Aleksander; Vandervorst, Robert

    2017-01-01

    Area and orientation preserving diffeomorphisms of the standard 2-disc, referred to as symplectomorphisms of D2, allow decompositions in terms of positive twist diffeomorphisms. Using the latter decomposition, we utilize the Conley index theory of discrete braid classes as introduced in Ghrist et

  19. The remarkable discreteness of being

    Indian Academy of Sciences (India)

    Life is a discrete, stochastic phenomenon: for a biological organism, the time of the two most important events of its life (reproduction and death) is random and these events change the number of individuals of the species by single units. These facts can have surprising, counterintuitive consequences. I review here three ...

  20. Discrete tomography in neutron radiography

    International Nuclear Information System (INIS)

    Kuba, Attila; Rodek, Lajos; Kiss, Zoltan; Rusko, Laszlo; Nagy, Antal; Balasko, Marton

    2005-01-01

    Discrete tomography (DT) is an imaging technique for reconstructing discrete images from their projections using the knowledge that the object to be reconstructed contains only a few homogeneous materials characterized by known discrete absorption values. One of the main reasons for applying DT is that we will hopefully require relatively few projections. Using discreteness and some a priori information (such as an approximate shape of the object) we can apply two DT methods in neutron imaging by reducing the problem to an optimization task. The first method is a special one because it is only suitable if the object is composed of cylinders and sphere shapes. The second method is a general one in the sense that it can be used for reconstructing objects of any shape. Software was developed and physical experiments performed in order to investigate the effects of several reconstruction parameters: the number of projections, noise levels, and complexity of the object to be reconstructed. We give a summary of the experimental results and make a comparison of the results obtained using a classical reconstruction technique (FBP). The programs we developed are available in our DT reconstruction program package DIRECT

  1. A developmental metatheory of psychopathology.

    Science.gov (United States)

    Karasu, T B

    1994-01-01

    The author proposes an integrative model of psychopathology in light of the contemporary need to bridge diverse ideological frameworks. This model has its major foundations in drive, ego, object relations, and self psychoanalytic perspectives as they impact upon interactional patterns of infancy. The chronology of these theoretical orientations is presented as parallel to a changing focus upon different successive stages in the course of individual development. The longstanding controversy between conflict and deficit theories, which undergirds the various schools of thought, is addressed: a developmental orientation is offered as the overriding conceptual connection between them. Conflict and deficit phenomena are regarded as intertwined and not incompatible: Unconscious drives, desires and wishes, ego defenses, and compromise formations as well as object relationship deficiencies and structural voids and defects in the self are combined to encompass a broad spectrum of psychopathology and its sources: the above intrapsychic and interpersonal factors are interfaced with significant reciprocal dyadic (mother/child) and triadic (father/mother/child) influences upon ongoing maturational processes. For heuristic purposes, a fourfold matrix--dyadic deficit, dyadic conflict, triadic deficit, and triadic conflict--is delineated. Clinical characteristics and developmental precursors of each of the four prototypes, especially with regard to early relational events, are examined.

  2. Discrete elements method of neutron transport

    International Nuclear Information System (INIS)

    Mathews, K.A.

    1988-01-01

    In this paper a new neutron transport method, called discrete elements (L N ) is derived and compared to discrete ordinates methods, theoretically and by numerical experimentation. The discrete elements method is based on discretizing the Boltzmann equation over a set of elements of angle. The discrete elements method is shown to be more cost-effective than discrete ordinates, in terms of accuracy versus execution time and storage, for the cases tested. In a two-dimensional test case, a vacuum duct in a shield, the L N method is more consistently convergent toward a Monte Carlo benchmark solution

  3. Staging atmospheres

    DEFF Research Database (Denmark)

    Bille, Mikkel; Bjerregaard, Peter; Sørensen, Tim Flohr

    2015-01-01

    The article introduces the special issue on staging atmospheres by surveying the philosophical, political and anthropological literature on atmosphere, and explores the relationship between atmosphere, material culture, subjectivity and affect. Atmosphere seems to occupy one of the classic...

  4. BEST-4, Fuel Cycle and Cost Optimization for Discrete Power Levels

    International Nuclear Information System (INIS)

    1973-01-01

    1 - Nature of physical problem solved: Determination of optimal power strategy for a fuel cycle, for discrete power levels and n temporal stages, taking into account replacement energy costs and de-rating. 2 - Method of solution: Dynamic programming. 3 - Restrictions on the complexity of the problem: Restrictions may arise from number of power levels and temporal stages, due to machine limitations

  5. Developmental perspectives on nutrition and obesity from gestation to adolescence.

    Science.gov (United States)

    Esposito, Layla; Fisher, Jennifer O; Mennella, Julie A; Hoelscher, Deanna M; Huang, Terry T

    2009-07-01

    Obesity results from a complex combination of factors that act at many stages throughout a person's life. Therefore, examining childhood nutrition and obesity from a developmental perspective is warranted. A developmental perspective recognizes the cumulative effects of factors that contribute to eating behavior and obesity, including biological and socioenvironmental factors that are relevant at different stages of development. A developmental perspective considers family, school, and community context. During gestation, risk factors for obesity include maternal diet, overweight, and smoking. In early childhood, feeding practices, taste acquisition, and eating in the absence of hunger must be considered. As children become more independent during middle childhood and adolescence, school nutrition, food marketing, and social networks become focal points for obesity prevention or intervention. Combining a multilevel approach with a developmental perspective can inform more effective and sustainable strategies for obesity prevention.

  6. Transgenerational developmental programming.

    Science.gov (United States)

    Aiken, Catherine E; Ozanne, Susan E

    2014-01-01

    The concept of developmental programming suggests that the early life environment influences offspring characteristics in later life, including the propensity to develop diseases such as the metabolic syndrome. There is now growing evidence that the effects of developmental programming may also manifest in further generations without further suboptimal exposure. This review considers the evidence, primarily from rodent models, for effects persisting to subsequent generations, and evaluates the mechanisms by which developmental programming may be transmitted to further generations. In particular, we focus on the potential role of the intrauterine environment in contributing to a developmentally programmed phenotype in subsequent generations. The literature was systematically searched at http://pubmed.org and http://scholar.google.com to identify published findings regarding transgenerational (F2 and beyond) developmental programming effects in human populations and animal models. Transmission of programming effects is often viewed as a form of epigenetic inheritance, either via the maternal or paternal line. Evidence exists for both germline and somatic inheritance of epigenetic modifications which may be responsible for phenotypic changes in further generations. However, there is increasing evidence for the role of both extra-genomic components of the zygote and the interaction of the developing conceptus with the intrauterine environment in propagating programming effects. The contribution of a suboptimal reproductive tract environment or maternal adaptations to pregnancy may be critical to inheritance of programming effects via the maternal line. As the effects of age exacerbate the programmed metabolic phenotype, advancing maternal age may increase the likelihood of developmental programming effects being transmitted to further generations. We suggest that developmental programming effects could be propagated through the maternal line de novo in generations

  7. Discrete gauge symmetries in discrete MSSM-like orientifolds

    International Nuclear Information System (INIS)

    Ibáñez, L.E.; Schellekens, A.N.; Uranga, A.M.

    2012-01-01

    Motivated by the necessity of discrete Z N symmetries in the MSSM to insure baryon stability, we study the origin of discrete gauge symmetries from open string sector U(1)'s in orientifolds based on rational conformal field theory. By means of an explicit construction, we find an integral basis for the couplings of axions and U(1) factors for all simple current MIPFs and orientifolds of all 168 Gepner models, a total of 32 990 distinct cases. We discuss how the presence of discrete symmetries surviving as a subgroup of broken U(1)'s can be derived using this basis. We apply this procedure to models with MSSM chiral spectrum, concretely to all known U(3)×U(2)×U(1)×U(1) and U(3)×Sp(2)×U(1)×U(1) configurations with chiral bi-fundamentals, but no chiral tensors, as well as some SU(5) GUT models. We find examples of models with Z 2 (R-parity) and Z 3 symmetries that forbid certain B and/or L violating MSSM couplings. Their presence is however relatively rare, at the level of a few percent of all cases.

  8. Positivity for Convective Semi-discretizations

    KAUST Repository

    Fekete, Imre; Ketcheson, David I.; Loczi, Lajos

    2017-01-01

    We propose a technique for investigating stability properties like positivity and forward invariance of an interval for method-of-lines discretizations, and apply the technique to study positivity preservation for a class of TVD semi-discretizations

  9. Developmental toxicology: adequacy of current methods.

    Science.gov (United States)

    Peters, P W

    1998-01-01

    Toxicology embraces several disciplines such as carcinogenicity, mutagenicity and reproductive toxicity. Reproductive toxicology is concerned with possible effects of substances on the reproductive process, i.e. on sexual organs and their functions, endocrine regulation, fertilization, transport of the fertilized ovum, implantation, and embryonic, fetal and postnatal development, until the end-differentiation of the organs is achieved. Reproductive toxicology is divided into areas related to male and female fertility, and developmental toxicology. Developmental toxicology can be further broken down into prenatal and postnatal toxicology. Today, much new information is available about the origins of developmental disorders resulting from chemical exposure. While these findings seem to promise important new developments in methodology and research, there is a danger of losing sight of the precepts and principles established in the light of existing knowledge. There is also a danger that we may fail to correct shortcomings in our existing procedures and practice. The aim of this presentation is to emphasize the importance of testing substances for their impact in advance of their use and to underline that we must use the best existing tools for carrying out risk assessments. Moreover, it needs to be stressed that there are many substances that are never assessed with respect to reproductive and developmental toxicity. Similarly, our programmes for post-marketing surveillance with respect to developmental toxicology are grossly inadequate. Our ability to identify risks to normal development and reproduction would be much improved, first if a number of straightforward precepts were always followed and second, if we had a clearer understanding of what we mean by risk and acceptable levels of risk in the context of development. Other aims of this paper are: to stress the complexity of the different stages of normal prenatal development; to note the principles that are

  10. Quantum chaos on discrete graphs

    International Nuclear Information System (INIS)

    Smilansky, Uzy

    2007-01-01

    Adapting a method developed for the study of quantum chaos on quantum (metric) graphs (Kottos and Smilansky 1997 Phys. Rev. Lett. 79 4794, Kottos and Smilansky 1999 Ann. Phys., NY 274 76), spectral ζ functions and trace formulae for discrete Laplacians on graphs are derived. This is achieved by expressing the spectral secular equation in terms of the periodic orbits of the graph and obtaining functions which belong to the class of ζ functions proposed originally by Ihara (1966 J. Mat. Soc. Japan 18 219) and expanded by subsequent authors (Stark and Terras 1996 Adv. Math. 121 124, Kotani and Sunada 2000 J. Math. Sci. Univ. Tokyo 7 7). Finally, a model of 'classical dynamics' on the discrete graph is proposed. It is analogous to the corresponding classical dynamics derived for quantum graphs (Kottos and Smilansky 1997 Phys. Rev. Lett. 79 4794, Kottos and Smilansky 1999 Ann. Phys., NY 274 76). (fast track communication)

  11. Dark energy from discrete spacetime.

    Directory of Open Access Journals (Sweden)

    Aaron D Trout

    Full Text Available Dark energy accounts for most of the matter-energy content of our universe, yet current theories of its origin rely on radical physical assumptions such as the holographic principle or controversial anthropic arguments. We give a better motivated explanation for dark energy, claiming that it arises from a small negative scalar-curvature present even in empty spacetime. The vacuum has this curvature because spacetime is fundamentally discrete and there are more ways for a discrete geometry to have negative curvature than positive. We explicitly compute this effect using a variant of the well known dynamical-triangulations (DT model for quantum gravity. Our model predicts a time-varying non-zero cosmological constant with a current value, [Formula: see text] in natural units, in agreement with observation. This calculation is made possible by a novel characterization of the possible DT action values combined with numerical evidence concerning their degeneracies.

  12. Applied geometry and discrete mathematics

    CERN Document Server

    Sturm; Gritzmann, Peter; Sturmfels, Bernd

    1991-01-01

    This volume, published jointly with the Association for Computing Machinery, comprises a collection of research articles celebrating the occasion of Victor Klee's sixty-fifth birthday in September 1990. During his long career, Klee has made contributions to a wide variety of areas, such as discrete and computational geometry, convexity, combinatorics, graph theory, functional analysis, mathematical programming and optimization, and theoretical computer science. In addition, Klee made important contributions to mathematics education, mathematical methods in economics and the decision sciences, applications of discrete mathematics in the biological and social sciences, and the transfer of knowledge from applied mathematics to industry. In honor of Klee's achievements, this volume presents more than forty papers on topics related to Klee's research. While the majority of the papers are research articles, a number of survey articles are also included. Mirroring the breadth of Klee's mathematical contributions, th...

  13. Emissivity of discretized diffusion problems

    International Nuclear Information System (INIS)

    Densmore, Jeffery D.; Davidson, Gregory; Carrington, David B.

    2006-01-01

    The numerical modeling of radiative transfer by the diffusion approximation can produce artificially damped radiation propagation if spatial cells are too optically thick. In this paper, we investigate this nonphysical behavior at external problem boundaries by examining the emissivity of the discretized diffusion approximation. We demonstrate that the standard cell-centered discretization produces an emissivity that is too low for optically thick cells, a situation that leads to the lack of radiation propagation. We then present a modified boundary condition that yields an accurate emissivity regardless of cell size. This modified boundary condition can be used with a deterministic calculation or as part of a hybrid transport-diffusion method for increasing the efficiency of Monte Carlo simulations. We also discuss the range of applicability, as a function of cell size and material properties, when this modified boundary condition is employed in a hybrid technique. With a set of numerical calculations, we demonstrate the accuracy and usefulness of this modified boundary condition

  14. Discrete symmetries in the MSSM

    Energy Technology Data Exchange (ETDEWEB)

    Schieren, Roland

    2010-12-02

    The use of discrete symmetries, especially abelian ones, in physics beyond the standard model of particle physics is discussed. A method is developed how a general, abelian, discrete symmetry can be obtained via spontaneous symmetry breaking. In addition, anomalies are treated in the path integral approach with special attention to anomaly cancellation via the Green-Schwarz mechanism. All this is applied to the minimal supersymmetric standard model. A unique Z{sup R}{sub 4} symmetry is discovered which solves the {mu}-problem as well as problems with proton decay and allows to embed the standard model gauge group into a simple group, i.e. the Z{sup R}{sub 4} is compatible with grand unification. Also the flavor problem in the context of minimal flavor violation is addressed. Finally, a string theory model is presented which exhibits the mentioned Z{sup R}{sub 4} symmetry and other desirable features. (orig.)

  15. Domain Discretization and Circle Packings

    DEFF Research Database (Denmark)

    Dias, Kealey

    A circle packing is a configuration of circles which are tangent with one another in a prescribed pattern determined by a combinatorial triangulation, where the configuration fills a planar domain or a two-dimensional surface. The vertices in the triangulation correspond to centers of circles...... to domain discretization problems such as triangulation and unstructured mesh generation techniques. We wish to ask ourselves the question: given a cloud of points in the plane (we restrict ourselves to planar domains), is it possible to construct a circle packing preserving the positions of the vertices...... and constrained meshes having predefined vertices as constraints. A standard method of two-dimensional mesh generation involves conformal mapping of the surface or domain to standardized shapes, such as a disk. Since circle packing is a new technique for constructing discrete conformal mappings, it is possible...

  16. Discrete Bose-Einstein spectra

    International Nuclear Information System (INIS)

    Vlad, Valentin I.; Ionescu-Pallas, Nicholas

    2001-03-01

    The Bose-Einstein energy spectrum of a quantum gas, confined in a rigid cubic box, is shown to become discrete and strongly dependent on the box geometry (size L), temperature, T and atomic mass number, A at , in the region of small γ=A at TV 1/3 . This behavior is the consequence of the random state degeneracy in the box. Furthermore, we demonstrate that the total energy does not obey the conventional law any longer, but a new law, which depends on γ and on the quantum gas fugacity. This energy law imposes a faster decrease to zero than it is classically expected, for γ→0. The lighter the gas atoms, the higher the temperatures or the box size, for the same effects in the discrete Bose-Einstein regime. (author)

  17. Discrete symmetries in the MSSM

    International Nuclear Information System (INIS)

    Schieren, Roland

    2010-01-01

    The use of discrete symmetries, especially abelian ones, in physics beyond the standard model of particle physics is discussed. A method is developed how a general, abelian, discrete symmetry can be obtained via spontaneous symmetry breaking. In addition, anomalies are treated in the path integral approach with special attention to anomaly cancellation via the Green-Schwarz mechanism. All this is applied to the minimal supersymmetric standard model. A unique Z R 4 symmetry is discovered which solves the μ-problem as well as problems with proton decay and allows to embed the standard model gauge group into a simple group, i.e. the Z R 4 is compatible with grand unification. Also the flavor problem in the context of minimal flavor violation is addressed. Finally, a string theory model is presented which exhibits the mentioned Z R 4 symmetry and other desirable features. (orig.)

  18. Dark energy from discrete spacetime.

    Science.gov (United States)

    Trout, Aaron D

    2013-01-01

    Dark energy accounts for most of the matter-energy content of our universe, yet current theories of its origin rely on radical physical assumptions such as the holographic principle or controversial anthropic arguments. We give a better motivated explanation for dark energy, claiming that it arises from a small negative scalar-curvature present even in empty spacetime. The vacuum has this curvature because spacetime is fundamentally discrete and there are more ways for a discrete geometry to have negative curvature than positive. We explicitly compute this effect using a variant of the well known dynamical-triangulations (DT) model for quantum gravity. Our model predicts a time-varying non-zero cosmological constant with a current value, [Formula: see text] in natural units, in agreement with observation. This calculation is made possible by a novel characterization of the possible DT action values combined with numerical evidence concerning their degeneracies.

  19. Discrete mathematics using a computer

    CERN Document Server

    Hall, Cordelia

    2000-01-01

    Several areas of mathematics find application throughout computer science, and all students of computer science need a practical working understanding of them. These core subjects are centred on logic, sets, recursion, induction, relations and functions. The material is often called discrete mathematics, to distinguish it from the traditional topics of continuous mathematics such as integration and differential equations. The central theme of this book is the connection between computing and discrete mathematics. This connection is useful in both directions: • Mathematics is used in many branches of computer science, in applica­ tions including program specification, datastructures,design and analysis of algorithms, database systems, hardware design, reasoning about the correctness of implementations, and much more; • Computers can help to make the mathematics easier to learn and use, by making mathematical terms executable, making abstract concepts more concrete, and through the use of software tools su...

  20. Duality for discrete integrable systems

    International Nuclear Information System (INIS)

    Quispel, G R W; Capel, H W; Roberts, J A G

    2005-01-01

    A new class of discrete dynamical systems is introduced via a duality relation for discrete dynamical systems with a number of explicitly known integrals. The dual equation can be defined via the difference of an arbitrary linear combination of integrals and its upshifted version. We give an example of an integrable mapping with two parameters and four integrals leading to a (four-dimensional) dual mapping with four parameters and two integrals. We also consider a more general class of higher-dimensional mappings arising via a travelling-wave reduction from the (integrable) MKdV partial-difference equation. By differencing the trace of the monodromy matrix we obtain a class of novel dual mappings which is shown to be integrable as level-set-dependent versions of the original ones

  1. Observability of discretized partial differential equations

    Science.gov (United States)

    Cohn, Stephen E.; Dee, Dick P.

    1988-01-01

    It is shown that complete observability of the discrete model used to assimilate data from a linear partial differential equation (PDE) system is necessary and sufficient for asymptotic stability of the data assimilation process. The observability theory for discrete systems is reviewed and applied to obtain simple observability tests for discretized constant-coefficient PDEs. Examples are used to show how numerical dispersion can result in discrete dynamics with multiple eigenvalues, thereby detracting from observability.

  2. Quantitative developmental transcriptomes of the Mediterranean sea urchin Paracentrotus lividus.

    Science.gov (United States)

    Gildor, Tsvia; Malik, Assaf; Sher, Noa; Avraham, Linor; Ben-Tabou de-Leon, Smadar

    2016-02-01

    Embryonic development progresses through the timely activation of thousands of differentially activated genes. Quantitative developmental transcriptomes provide the means to relate global patterns of differentially expressed genes to the emerging body plans they generate. The sea urchin is one of the classic model systems for embryogenesis and the models of its developmental gene regulatory networks are of the most comprehensive of their kind. Thus, the sea urchin embryo is an excellent system for studies of its global developmental transcriptional profiles. Here we produced quantitative developmental transcriptomes of the sea urchin Paracentrotus lividus (P. lividus) at seven developmental stages from the fertilized egg to prism stage. We generated de-novo reference transcriptome and identified 29,817 genes that are expressed at this time period. We annotated and quantified gene expression at the different developmental stages and confirmed the reliability of the expression profiles by QPCR measurement of a subset of genes. The progression of embryo development is reflected in the observed global expression patterns and in our principle component analysis. Our study illuminates the rich patterns of gene expression that participate in sea urchin embryogenesis and provide an essential resource for further studies of the dynamic expression of P. lividus genes. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Effective lagrangian description on discrete gauge symmetries

    International Nuclear Information System (INIS)

    Banks, T.

    1989-01-01

    We exhibit a simple low-energy lagrangian which describes a system with a discrete remnant of a spontaneously broken continuous gauge symmetry. The lagrangian gives a simple description of the effects ascribed to such systems by Krauss and Wilczek: black holes carry discrete hair and interact with cosmic strings, and wormholes cannot lead to violation of discrete gauge symmetries. (orig.)

  4. Discrete port-Hamiltonian systems : mixed interconnections

    NARCIS (Netherlands)

    Talasila, Viswanath; Clemente-Gallardo, J.; Schaft, A.J. van der

    2005-01-01

    Either from a control theoretic viewpoint or from an analysis viewpoint it is necessary to convert smooth systems to discrete systems, which can then be implemented on computers for numerical simulations. Discrete models can be obtained either by discretizing a smooth model, or by directly modeling

  5. Discrete fractional solutions of a Legendre equation

    Science.gov (United States)

    Yılmazer, Resat

    2018-01-01

    One of the most popular research interests of science and engineering is the fractional calculus theory in recent times. Discrete fractional calculus has also an important position in fractional calculus. In this work, we acquire new discrete fractional solutions of the homogeneous and non homogeneous Legendre differential equation by using discrete fractional nabla operator.

  6. Reading in developmental prosopagnosia

    DEFF Research Database (Denmark)

    Starrfelt, Randi; Klargaard, Solja K; Petersen, Anders

    2018-01-01

    exposure durations (targeting the word superiority effect), and d) text reading. RESULTS: Participants with developmental prosopagnosia performed strikingly similar to controls across the four reading tasks. Formal analysis revealed a significant dissociation between word and face recognition......, that is, impaired reading in developmental prosopagnosia. METHOD: We tested 10 adults with developmental prosopagnosia and 20 matched controls. All participants completed the Cambridge Face Memory Test, the Cambridge Face Perception test and a Face recognition questionnaire used to quantify everyday face...... recognition experience. Reading was measured in four experimental tasks, testing different levels of letter, word, and text reading: (a) single word reading with words of varying length,(b) vocal response times in single letter and short word naming, (c) recognition of single letters and short words at brief...

  7. The Developmental Work

    DEFF Research Database (Denmark)

    Møller, Niels; Hvid, Helge

    2001-01-01

    AbstractIn the nineties, the concept of the developmental work (DW) has become a significant point of orientation for the actors on Danish labour market. The DW has moved the focus of the labour market from wages and working time towards work and production. For employees, the DW promises...... developmental possibilities, influence and responsibility, but also greater social responsibility for the firm. For firms, the DW promises increased competitiveness and better products. In this paper we present the concept of the DW as one which encourages the development of work, production and organisation...... of the firm and show that the DW is different from mainstream management concepts, as the DW...

  8. Continuous versus discrete structures II -- Discrete Hamiltonian systems and Helmholtz conditions

    OpenAIRE

    Cresson, Jacky; Pierret, Frédéric

    2015-01-01

    We define discrete Hamiltonian systems in the framework of discrete embeddings. An explicit comparison with previous attempts is given. We then solve the discrete Helmholtz's inverse problem for the discrete calculus of variation in the Hamiltonian setting. Several applications are discussed.

  9. Asymptotic behavior of discrete holomorphic maps z^c, log(z) and discrete Painleve transcedents

    OpenAIRE

    Agafonov, S. I.

    2005-01-01

    It is shown that discrete analogs of z^c and log(z) have the same asymptotic behavior as their smooth counterparts. These discrete maps are described in terms of special solutions of discrete Painleve-II equations, asymptotics of these solutions providing the behaviour of discrete z^c and log(z) at infinity.

  10. Discrete integrable couplings associated with Toda-type lattice and two hierarchies of discrete soliton equations

    International Nuclear Information System (INIS)

    Zhang Yufeng; Fan Engui; Zhang Yongqing

    2006-01-01

    With the help of two semi-direct sum Lie algebras, an efficient way to construct discrete integrable couplings is proposed. As its applications, the discrete integrable couplings of the Toda-type lattice equations are obtained. The approach can be devoted to establishing other discrete integrable couplings of the discrete lattice integrable hierarchies of evolution equations

  11. Do patients prefer mesh or anterior colporrhaphy for primary correction of anterior vaginal wall prolapse: a labelled discrete choice experiment

    NARCIS (Netherlands)

    Notten, K. J. B.; Essers, B. A.; Weemhoff, M.; Rutten, A. G. H.; Donners, J. J. A. E.; van Gestel, I.; Kruitwagen, R. F. M. P.; Roovers, J. P. W. R.; Dirksen, C. D.

    2015-01-01

    We investigated patients' preferences for anterior colporrhaphy or mesh surgery as surgical correction of anterior vaginal wall prolapse. Labelled discrete choice experiment. Three Dutch teaching hospitals. Women with anterior vaginal wall prolapse Pelvic Organ Prolapse Quantification stage 2 or

  12. Cuspidal discrete series for projective hyperbolic spaces

    DEFF Research Database (Denmark)

    Andersen, Nils Byrial; Flensted-Jensen, Mogens

    2013-01-01

    Abstract. We have in [1] proposed a definition of cusp forms on semisimple symmetric spaces G/H, involving the notion of a Radon transform and a related Abel transform. For the real non-Riemannian hyperbolic spaces, we showed that there exists an infinite number of cuspidal discrete series......, and at most finitely many non-cuspidal discrete series, including in particular the spherical discrete series. For the projective spaces, the spherical discrete series are the only non-cuspidal discrete series. Below, we extend these results to the other hyperbolic spaces, and we also study the question...

  13. Space-Time Discrete KPZ Equation

    Science.gov (United States)

    Cannizzaro, G.; Matetski, K.

    2018-03-01

    We study a general family of space-time discretizations of the KPZ equation and show that they converge to its solution. The approach we follow makes use of basic elements of the theory of regularity structures (Hairer in Invent Math 198(2):269-504, 2014) as well as its discrete counterpart (Hairer and Matetski in Discretizations of rough stochastic PDEs, 2015. arXiv:1511.06937). Since the discretization is in both space and time and we allow non-standard discretization for the product, the methods mentioned above have to be suitably modified in order to accommodate the structure of the models under study.

  14. Developmental Stages of some Tropical and Subtropical Planktonic Marine Copepods

    NARCIS (Netherlands)

    Björnberg, Tagea K.S.

    1972-01-01

    Most planktonic marine copepods have nauplii which differ greatly from the copepodids so that it is difficult to relate them to the adult form. Rearing experiments are usually unsuccessful; only 8% of ca. 800 species of planktonic marine copepods have identified nauplii (see below cited list). To

  15. Developmental stages in experimental liver metastases: relation to invasiveness

    NARCIS (Netherlands)

    Dingemans, K. P.; van den Bergh Weerman, M. A.; Keep, R. F.; Das, P. K.

    1994-01-01

    We have previously reported that an invasive morphotype can be evoked in a rat colon carcinoma by transplanting it into pre-induced subcutaneous granulation tissue. We have now studied the interaction of the same tumor with liver tissue, which is extremely poor in connective tissue in comparison

  16. Developmental stage and pulsing in inflorescences of torch ginger

    Directory of Open Access Journals (Sweden)

    Daniella Nogueira Moraes Carneiro

    2014-11-01

    through scores on a 0-4 point scale. Commercial vase life of stalks is longer (10 days when inflorescences are harvested with 1/3 bracts opened. It is recommended to carry out pulsing in torch ginger flower stems with concentration of 20% sucrose for 24h for inflorescences harvested with 1/3 or 2/3 of the bracts opened.

  17. Biomarkers of adult and developmental neurotoxicity

    International Nuclear Information System (INIS)

    Slikker, William; Bowyer, John F.

    2005-01-01

    Neurotoxicity may be defined as any adverse effect on the structure or function of the central and/or peripheral nervous system by a biological, chemical, or physical agent. A multidisciplinary approach is necessary to assess adult and developmental neurotoxicity due to the complex and diverse functions of the nervous system. The overall strategy for understanding developmental neurotoxicity is based on two assumptions: (1) significant differences in the adult versus the developing nervous system susceptibility to neurotoxicity exist and they are often developmental stage dependent; (2) a multidisciplinary approach using neurobiological, including gene expression assays, neurophysiological, neuropathological, and behavioral function is necessary for a precise assessment of neurotoxicity. Application of genomic approaches to developmental studies must use the same criteria for evaluating microarray studies as those in adults including consideration of reproducibility, statistical analysis, homogenous cell populations, and confirmation with non-array methods. A study using amphetamine to induce neurotoxicity supports the following: (1) gene expression data can help define neurotoxic mechanism(s) (2) gene expression changes can be useful biomarkers of effect, and (3) the site-selective nature of gene expression in the nervous system may mandate assessment of selective cell populations

  18. Integrable discretizations of the short pulse equation

    International Nuclear Information System (INIS)

    Feng Baofeng; Maruno, Ken-ichi; Ohta, Yasuhiro

    2010-01-01

    In this paper, we propose integrable semi-discrete and full-discrete analogues of the short pulse (SP) equation. The key construction is the bilinear form and determinant structure of solutions of the SP equation. We also give the determinant formulas of N-soliton solutions of the semi-discrete and full-discrete analogues of the SP equations, from which the multi-loop and multi-breather solutions can be generated. In the continuous limit, the full-discrete SP equation converges to the semi-discrete SP equation, and then to the continuous SP equation. Based on the semi-discrete SP equation, an integrable numerical scheme, i.e. a self-adaptive moving mesh scheme, is proposed and used for the numerical computation of the short pulse equation.

  19. Arguments from Developmental Order.

    Science.gov (United States)

    Stöckle-Schobel, Richard

    2016-01-01

    In this article, I investigate a special type of argument regarding the role of development in theorizing about psychological processes and cognitive capacities. Among the issues that developmental psychologists study, discovering the ontogenetic trajectory of mechanisms or capacities underpinning our cognitive functions ranks highly. The order in which functions are developed or capacities are acquired is a matter of debate between competing psychological theories, and also philosophical conceptions of the mind - getting the role and the significance of the different steps in this order right could be seen as an important virtue of such theories. Thus, a special kind of strategy in arguments between competing philosophical or psychological theories is using developmental order in arguing for or against a given psychological claim. In this article, I will introduce an analysis of arguments from developmental order, which come in two general types: arguments emphasizing the importance of the early cognitive processes and arguments emphasizing the late cognitive processes. I will discuss their role in one of the central tools for evaluating scientific theories, namely in making inferences to the best explanation. I will argue that appeal to developmental order is, by itself, an insufficient criterion for theory choice and has to be part of an argument based on other core explanatory or empirical virtues. I will end by proposing a more concerted study of philosophical issues concerning (cognitive) development, and I will present some topics that also pertain to a full-fledged 'philosophy of development.'

  20. Developmental Education Evaluation Model.

    Science.gov (United States)

    Perry-Miller, Mitzi; And Others

    A developmental education evaluation model designed to be used at a multi-unit urban community college is described. The purpose of the design was to determine the cost effectiveness/worth of programs in order to initiate self-improvement. A needs assessment was conducted by interviewing and taping the responses of students, faculty, staff, and…

  1. Arguments from Developmental Order

    Directory of Open Access Journals (Sweden)

    Richard eStöckle-Schobel

    2016-05-01

    Full Text Available In this article, I investigate a special type of argument regarding the role of development in theorising about psychological processes and cognitive capacities. Among the issues that developmental psychologists study, discovering the ontogenetic trajectory of mechanisms or capacities underpinning our cognitive functions ranks highly. The order in which functions are developed or capacities are acquired is a matter of debate between competing psychological theories, and also philosophical conceptions of the mind – getting the role and the significance of the different steps in this order right could be seen as an important virtue of such theories.Thus, a special kind of strategy in arguments between competing philosophical or psychological theories is using developmental order in arguing for or against a given psychological claim. In this article, I will introduce an analysis of arguments from developmental order, which come in two general types: arguments emphasising the importance of the early cognitive processes and arguments emphasising the late cognitive processes. I will discuss their role in one of the central tools for evaluating scientific theories, namely in making inferences to the best explanation. I will argue that appeal to developmental order is, by itself, an insufficient criterion for theory choice and has to be part of an argument based on other core explanatory or empirical virtues. I will end by proposing a more concerted study of philosophical issues concerning (cognitive development, and I will present some topics that also pertain to a full-fledged ‘philosophy of development’.

  2. Developmental paediatric anaesthetic pharmacology

    DEFF Research Database (Denmark)

    Hansen, Tom Giedsing

    2015-01-01

    Safe and effective drug therapy in neonates, infants and children require detailed knowledge about the ontogeny of drug disposition and action as well how these interact with genetics and co-morbidity of children. Recent advances in developmental pharmacology in children follow the increased...

  3. Building clinical networks: a developmental evaluation framework.

    Science.gov (United States)

    Carswell, Peter; Manning, Benjamin; Long, Janet; Braithwaite, Jeffrey

    2014-05-01

    Clinical networks have been designed as a cross-organisational mechanism to plan and deliver health services. With recent concerns about the effectiveness of these structures, it is timely to consider an evidence-informed approach for how they can be developed and evaluated. To document an evaluation framework for clinical networks by drawing on the network evaluation literature and a 5-year study of clinical networks. We searched literature in three domains: network evaluation, factors that aid or inhibit network development, and on robust methods to measure network characteristics. This material was used to build a framework required for effective developmental evaluation. The framework's architecture identifies three stages of clinical network development; partner selection, network design and network management. Within each stage is evidence about factors that act as facilitators and barriers to network growth. These factors can be used to measure progress via appropriate methods and tools. The framework can provide for network growth and support informed decisions about progress. For the first time in one place a framework incorporating rigorous methods and tools can identify factors known to affect the development of clinical networks. The target user group is internal stakeholders who need to conduct developmental evaluation to inform key decisions along their network's developmental pathway.

  4. Developmental Exposure to an Environmental PCB Mixture ...

    Science.gov (United States)

    Developmental PCB exposure impairs hearing and induces brainstem audiogenic seizures in adult offspring. The degree to which this enhanced susceptibility to seizure is manifest in other brain regions has not been examined. Thus, electrical kindling of the amygdala was used to evaluate the effect of developmental exposure to an environmentally relevant PCB mixture on seizure susceptibility in the rat. Female Long-Evans rats were dosed orally with 0 or 6 mg/kg/day of the PCB mixture dissolved in corn oil vehicle during the perinatal period. On postnatal day (PND) 21, pups were weaned, and two males from each litter were randomly selected for the kindling study. As adults, the male rats were implanted bilaterally with electrodes in the basolateral amygdala. For each animal, afterdischarge (AD) thresholds in the amygdala were determined on the first day of testing followed by once daily stimulation at a standard 200 µA stimulus intensity until three stage 5 generalized seizures (GS) ensued. Developmental PCB exposure did not affect the AD threshold or total cumulative AD duration, but PCB exposure did increase the latency to behavioral manifestations of seizure propagation. PCB exposed animals required significantly more stimulations to reach stage 2 seizures compared to control animals, indicating an attenuated focal (amygdala) excitability. A delay in kindling progression from a focally stimulated limbic site stands in contrast to our previous finding of increase

  5. Discrete geometric structures for architecture

    KAUST Repository

    Pottmann, Helmut

    2010-06-13

    The emergence of freeform structures in contemporary architecture raises numerous challenging research problems, most of which are related to the actual fabrication and are a rich source of research topics in geometry and geometric computing. The talk will provide an overview of recent progress in this field, with a particular focus on discrete geometric structures. Most of these result from practical requirements on segmenting a freeform shape into planar panels and on the physical realization of supporting beams and nodes. A study of quadrilateral meshes with planar faces reveals beautiful relations to discrete differential geometry. In particular, we discuss meshes which discretize the network of principal curvature lines. Conical meshes are among these meshes; they possess conical offset meshes at a constant face/face distance, which in turn leads to a supporting beam layout with so-called torsion free nodes. This work can be generalized to a variety of multilayer structures and laid the ground for an adapted curvature theory for these meshes. There are also efforts on segmenting surfaces into planar hexagonal panels. Though these are less constrained than planar quadrilateral panels, this problem is still waiting for an elegant solution. Inspired by freeform designs in architecture which involve circles and spheres, we present a new kind of triangle mesh whose faces\\' in-circles form a packing, i.e., the in-circles of two triangles with a common edge have the same contact point on that edge. These "circle packing (CP) meshes" exhibit an aesthetic balance of shape and size of their faces. They are closely tied to sphere packings on surfaces and to various remarkable structures and patterns which are of interest in art, architecture, and design. CP meshes constitute a new link between architectural freeform design and computational conformal geometry. Recently, certain timber structures motivated us to study discrete patterns of geodesics on surfaces. This

  6. Radiative transfer on discrete spaces

    CERN Document Server

    Preisendorfer, Rudolph W; Stark, M; Ulam, S

    1965-01-01

    Pure and Applied Mathematics, Volume 74: Radiative Transfer on Discrete Spaces presents the geometrical structure of natural light fields. This book describes in detail with mathematical precision the radiometric interactions of light-scattering media in terms of a few well established principles.Organized into four parts encompassing 15 chapters, this volume begins with an overview of the derivations of the practical formulas and the arrangement of formulas leading to numerical solution procedures of radiative transfer problems in plane-parallel media. This text then constructs radiative tran

  7. Stage line diagram: An age-conditional reference diagram for tracking development

    NARCIS (Netherlands)

    Buuren, S. van; Ooms, J.C.L.

    2009-01-01

    This paper presents a method for calculating stage line diagrams, a novel type of reference diagram useful for tracking developmental processes over time. Potential fields of applications include: dentistry (tooth eruption), oncology (tumor grading, cancer staging), virology (HIV infection and

  8. Stage line diagram: an age-conditional reference diagram for tracking development.

    NARCIS (Netherlands)

    Van Buuren, S.; Ooms, J.C.L.

    2009-01-01

    This paper presents a method for calculating stage line diagrams, a novel type of reference diagram useful for tracking developmental processes over time. Potential fields of applications include: dentistry (tooth eruption), oncology (tumor grading, cancer staging), virology (HIV infection and

  9. The discrete Kalman filtering approach for seismic signals deconvolution

    International Nuclear Information System (INIS)

    Kurniadi, Rizal; Nurhandoko, Bagus Endar B.

    2012-01-01

    Seismic signals are a convolution of reflectivity and seismic wavelet. One of the most important stages in seismic data processing is deconvolution process; the process of deconvolution is inverse filters based on Wiener filter theory. This theory is limited by certain modelling assumptions, which may not always valid. The discrete form of the Kalman filter is then used to generate an estimate of the reflectivity function. The main advantage of Kalman filtering is capability of technique to handling continually time varying models and has high resolution capabilities. In this work, we use discrete Kalman filter that it was combined with primitive deconvolution. Filtering process works on reflectivity function, hence the work flow of filtering is started with primitive deconvolution using inverse of wavelet. The seismic signals then are obtained by convoluting of filtered reflectivity function with energy waveform which is referred to as the seismic wavelet. The higher frequency of wavelet gives smaller wave length, the graphs of these results are presented.

  10. Discrete geometry: speculations on a new framework for classical electrodynamics

    International Nuclear Information System (INIS)

    Hemion, G.

    1988-01-01

    An attempt is made to describe the basic principles of physics in terms of discrete partially ordered sets. Geometric ideas are introduced by means of an action at a distance formulation of classical electrodynamics. The speculations are in two main directions: (i) Gravity, one of the four elementary forces of nature, seems to be fundamentally different from the other three forces. Could it be that gravity can be explained as a natural consequence of the discrete structure? (ii) The problem of the observer in quantum mechanics continues to cause conceptual problems. Can quantum statistics be explained in terms of finite ensembles of possible partially ordered sets? The development is guided at all stages by reference to the simplest, and most well-established principles of physics

  11. 3-D discrete analytical ridgelet transform.

    Science.gov (United States)

    Helbert, David; Carré, Philippe; Andres, Eric

    2006-12-01

    In this paper, we propose an implementation of the 3-D Ridgelet transform: the 3-D discrete analytical Ridgelet transform (3-D DART). This transform uses the Fourier strategy for the computation of the associated 3-D discrete Radon transform. The innovative step is the definition of a discrete 3-D transform with the discrete analytical geometry theory by the construction of 3-D discrete analytical lines in the Fourier domain. We propose two types of 3-D discrete lines: 3-D discrete radial lines going through the origin defined from their orthogonal projections and 3-D planes covered with 2-D discrete line segments. These discrete analytical lines have a parameter called arithmetical thickness, allowing us to define a 3-D DART adapted to a specific application. Indeed, the 3-D DART representation is not orthogonal, It is associated with a flexible redundancy factor. The 3-D DART has a very simple forward/inverse algorithm that provides an exact reconstruction without any iterative method. In order to illustrate the potentiality of this new discrete transform, we apply the 3-D DART and its extension to the Local-DART (with smooth windowing) to the denoising of 3-D image and color video. These experimental results show that the simple thresholding of the 3-D DART coefficients is efficient.

  12. Developmental toxicity of organotin compounds in animals

    Directory of Open Access Journals (Sweden)

    Lijiao eWu

    2014-09-01

    Full Text Available Organotin compounds (OTs have been used as biocides in antifouling paints and agriculture. The IMO introduced a global ban on the use of OTs in antifouling systems in 2001 due to their high toxicity. However, OTs have still been detected in the environment and pose a threat to the ecosystem. Several research groups have summarized the analytical methods, environmental fate, biochemistry, reproductive toxicity and mechanisms of actions of OTs. Here, we reviewed the developmental toxicity of OTs in various organisms such as sea urchin, ascidian, mussel and fish. The differences in sensitivity to OT exposure exist not only in different species but also at different stages in the same species. Though some hypotheses have been proposed to explain the developmental toxicity of OTs, the solid evidences are greatly in need.

  13. NIDCAP and developmental care

    Directory of Open Access Journals (Sweden)

    Dominique Haumont

    2014-06-01

    Full Text Available Perinatal mortality in very low birth weight infants has dramatically decreased during the last decades. However, 15-25% of these infants will show neurodevelopmental impairment later on. The aim of implementing early developmental care (EDC, emerged as a new field in neonatology, is to create an intervention program designed to provide support for optimal neurobehavioral development during this highly vulnerable period of brain growth. The theoretical framework, which underlies the approach, is supported by research in different scientific fields, including neuroscience, psychology, medicine and nursing. EDC utilizes a range of medical and nursing interventions that aim to decrease the stress of preterm neonates in neonatal intensive care units (NICUs. The Neonatal Individualized Developmental Care Assessment Program (NIDCAP is an integrated and holistic form of family-centered developmental care. Changing the traditional NICU towards an EDC-NICU includes training nursing and medical staff, investing in their quality and most importantly keeping parents in proximity to the infants. The new challenge of modern neonatology is to restore the mother-infant dyad applying “couplet care” starting at birth until discharge. Most of the European NICUs apply some elements of EDC, but it is more consistent in northern Europe. The development of NIDCAP training centers in Europe demonstrates the evolution of care. It is likely that future research and intervention programs will optimize our practices. Developmental care could prove to be an important recent step in improving outcome in extremely preterm neonates. Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

  14. Effect of gamma radiation on different stages of Indian meal moth ...

    African Journals Online (AJOL)

    Indian meal moth Plodia interpunctella Hübner is one of the most important stored products pests in the world. In this research, the effect of gamma irradiation was studied on different developmental stages of this pest and the doses required to prevent each of these developmental stages was investigated. From the results ...

  15. Evolutionary and developmental modules.

    Science.gov (United States)

    Lacquaniti, Francesco; Ivanenko, Yuri P; d'Avella, Andrea; Zelik, Karl E; Zago, Myrka

    2013-01-01

    The identification of biological modules at the systems level often follows top-down decomposition of a task goal, or bottom-up decomposition of multidimensional data arrays into basic elements or patterns representing shared features. These approaches traditionally have been applied to mature, fully developed systems. Here we review some results from two other perspectives on modularity, namely the developmental and evolutionary perspective. There is growing evidence that modular units of development were highly preserved and recombined during evolution. We first consider a few examples of modules well identifiable from morphology. Next we consider the more difficult issue of identifying functional developmental modules. We dwell especially on modular control of locomotion to argue that the building blocks used to construct different locomotor behaviors are similar across several animal species, presumably related to ancestral neural networks of command. A recurrent theme from comparative studies is that the developmental addition of new premotor modules underlies the postnatal acquisition and refinement of several different motor behaviors in vertebrates.

  16. Fermion systems in discrete space-time

    International Nuclear Information System (INIS)

    Finster, Felix

    2007-01-01

    Fermion systems in discrete space-time are introduced as a model for physics on the Planck scale. We set up a variational principle which describes a non-local interaction of all fermions. This variational principle is symmetric under permutations of the discrete space-time points. We explain how for minimizers of the variational principle, the fermions spontaneously break this permutation symmetry and induce on space-time a discrete causal structure

  17. Fermion systems in discrete space-time

    Energy Technology Data Exchange (ETDEWEB)

    Finster, Felix [NWF I - Mathematik, Universitaet Regensburg, 93040 Regensburg (Germany)

    2007-05-15

    Fermion systems in discrete space-time are introduced as a model for physics on the Planck scale. We set up a variational principle which describes a non-local interaction of all fermions. This variational principle is symmetric under permutations of the discrete space-time points. We explain how for minimizers of the variational principle, the fermions spontaneously break this permutation symmetry and induce on space-time a discrete causal structure.

  18. Fermion Systems in Discrete Space-Time

    OpenAIRE

    Finster, Felix

    2006-01-01

    Fermion systems in discrete space-time are introduced as a model for physics on the Planck scale. We set up a variational principle which describes a non-local interaction of all fermions. This variational principle is symmetric under permutations of the discrete space-time points. We explain how for minimizers of the variational principle, the fermions spontaneously break this permutation symmetry and induce on space-time a discrete causal structure.

  19. Fermion systems in discrete space-time

    Science.gov (United States)

    Finster, Felix

    2007-05-01

    Fermion systems in discrete space-time are introduced as a model for physics on the Planck scale. We set up a variational principle which describes a non-local interaction of all fermions. This variational principle is symmetric under permutations of the discrete space-time points. We explain how for minimizers of the variational principle, the fermions spontaneously break this permutation symmetry and induce on space-time a discrete causal structure.

  20. Developmental Transcriptomic Features of the Carcinogenic Liver Fluke, Clonorchis sinensis

    Science.gov (United States)

    Cho, Pyo Yun; Kim, Tae Im; Cho, Shin-Hyeong; Choi, Sang-Haeng; Park, Hong-Seog; Kim, Tong-Soo; Hong, Sung-Jong

    2011-01-01

    Clonorchis sinensis is the causative agent of the life-threatening disease endemic to China, Korea, and Vietnam. It is estimated that about 15 million people are infected with this fluke. C. sinensis provokes inflammation, epithelial hyperplasia, and periductal fibrosis in bile ducts, and may cause cholangiocarcinoma in chronically infected individuals. Accumulation of a large amount of biological information about the adult stage of this liver fluke in recent years has advanced our understanding of the pathological interplay between this parasite and its hosts. However, no developmental gene expression profiles of C. sinensis have been published. In this study, we generated gene expression profiles of three developmental stages of C. sinensis by analyzing expressed sequence tags (ESTs). Complementary DNA libraries were constructed from the adult, metacercaria, and egg developmental stages of C. sinensis. A total of 52,745 ESTs were generated and assembled into 12,830 C. sinensis assembled EST sequences, and then these assemblies were further categorized into groups according to biological functions and developmental stages. Most of the genes that were differentially expressed in the different stages were consistent with the biological and physical features of the particular developmental stage; high energy metabolism, motility and reproduction genes were differentially expressed in adults, minimal metabolism and final host adaptation genes were differentially expressed in metacercariae, and embryonic genes were differentially expressed in eggs. The higher expression of glucose transporters, proteases, and antioxidant enzymes in the adults accounts for active uptake of nutrients and defense against host immune attacks. The types of ion channels present in C. sinensis are consistent with its parasitic nature and phylogenetic placement in the tree of life. We anticipate that the transcriptomic information on essential regulators of development, bile chemotaxis, and

  1. Developmental transcriptomic features of the carcinogenic liver fluke, Clonorchis sinensis.

    Directory of Open Access Journals (Sweden)

    Won Gi Yoo

    2011-06-01

    Full Text Available Clonorchis sinensis is the causative agent of the life-threatening disease endemic to China, Korea, and Vietnam. It is estimated that about 15 million people are infected with this fluke. C. sinensis provokes inflammation, epithelial hyperplasia, and periductal fibrosis in bile ducts, and may cause cholangiocarcinoma in chronically infected individuals. Accumulation of a large amount of biological information about the adult stage of this liver fluke in recent years has advanced our understanding of the pathological interplay between this parasite and its hosts. However, no developmental gene expression profiles of C. sinensis have been published. In this study, we generated gene expression profiles of three developmental stages of C. sinensis by analyzing expressed sequence tags (ESTs. Complementary DNA libraries were constructed from the adult, metacercaria, and egg developmental stages of C. sinensis. A total of 52,745 ESTs were generated and assembled into 12,830 C. sinensis assembled EST sequences, and then these assemblies were further categorized into groups according to biological functions and developmental stages. Most of the genes that were differentially expressed in the different stages were consistent with the biological and physical features of the particular developmental stage; high energy metabolism, motility and reproduction genes were differentially expressed in adults, minimal metabolism and final host adaptation genes were differentially expressed in metacercariae, and embryonic genes were differentially expressed in eggs. The higher expression of glucose transporters, proteases, and antioxidant enzymes in the adults accounts for active uptake of nutrients and defense against host immune attacks. The types of ion channels present in C. sinensis are consistent with its parasitic nature and phylogenetic placement in the tree of life. We anticipate that the transcriptomic information on essential regulators of development

  2. Inevitable randomness in discrete mathematics

    CERN Document Server

    Beck, Jozsef

    2009-01-01

    Mathematics has been called the science of order. The subject is remarkably good for generalizing specific cases to create abstract theories. However, mathematics has little to say when faced with highly complex systems, where disorder reigns. This disorder can be found in pure mathematical arenas, such as the distribution of primes, the 3n+1 conjecture, and class field theory. The purpose of this book is to provide examples--and rigorous proofs--of the complexity law: (1) discrete systems are either simple or they exhibit advanced pseudorandomness; (2) a priori probabilities often exist even when there is no intrinsic symmetry. Part of the difficulty in achieving this purpose is in trying to clarify these vague statements. The examples turn out to be fascinating instances of deep or mysterious results in number theory and combinatorics. This book considers randomness and complexity. The traditional approach to complexity--computational complexity theory--is to study very general complexity classes, such as P...

  3. Quantum evolution by discrete measurements

    International Nuclear Information System (INIS)

    Roa, L; Guevara, M L Ladron de; Delgado, A; Olivares-RenterIa, G; Klimov, A B

    2007-01-01

    In this article we review two ways of driving a quantum system to a known pure state via a sequence discrete of von Neumann measurements. The first of them assumes that the initial state of the system is unknown, and the evolution is attained only with the help of two non-commuting observables. For this method, the overall success probability is maximized when the eigentstates of the involved observables constitute mutually unbiased bases. The second method assumes the initial state is known and it uses N observables which are consecutively measured to make the state of the system approach the target state. The probability of success of this procedure converges to 1 as the number of observables increases

  4. Quantum evolution by discrete measurements

    Energy Technology Data Exchange (ETDEWEB)

    Roa, L [Center for Quantum Optics and Quantum Information, Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile); Guevara, M L Ladron de [Departamento de Fisica, Universidad Catolica del Norte, Casilla 1280, Antofagasta (Chile); Delgado, A [Center for Quantum Optics and Quantum Information, Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile); Olivares-RenterIa, G [Center for Quantum Optics and Quantum Information, Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile); Klimov, A B [Departamento de Fisica, Universidad de Guadalajara, Revolucion 1500, 44420 Guadalajara, Jalisco (Mexico)

    2007-10-15

    In this article we review two ways of driving a quantum system to a known pure state via a sequence discrete of von Neumann measurements. The first of them assumes that the initial state of the system is unknown, and the evolution is attained only with the help of two non-commuting observables. For this method, the overall success probability is maximized when the eigentstates of the involved observables constitute mutually unbiased bases. The second method assumes the initial state is known and it uses N observables which are consecutively measured to make the state of the system approach the target state. The probability of success of this procedure converges to 1 as the number of observables increases.

  5. Discrete stochastic processes and applications

    CERN Document Server

    Collet, Jean-François

    2018-01-01

    This unique text for beginning graduate students gives a self-contained introduction to the mathematical properties of stochastics and presents their applications to Markov processes, coding theory, population dynamics, and search engine design. The book is ideal for a newly designed course in an introduction to probability and information theory. Prerequisites include working knowledge of linear algebra, calculus, and probability theory. The first part of the text focuses on the rigorous theory of Markov processes on countable spaces (Markov chains) and provides the basis to developing solid probabilistic intuition without the need for a course in measure theory. The approach taken is gradual beginning with the case of discrete time and moving on to that of continuous time. The second part of this text is more applied; its core introduces various uses of convexity in probability and presents a nice treatment of entropy.

  6. Discrete calculus methods for counting

    CERN Document Server

    Mariconda, Carlo

    2016-01-01

    This book provides an introduction to combinatorics, finite calculus, formal series, recurrences, and approximations of sums. Readers will find not only coverage of the basic elements of the subjects but also deep insights into a range of less common topics rarely considered within a single book, such as counting with occupancy constraints, a clear distinction between algebraic and analytical properties of formal power series, an introduction to discrete dynamical systems with a thorough description of Sarkovskii’s theorem, symbolic calculus, and a complete description of the Euler-Maclaurin formulas and their applications. Although several books touch on one or more of these aspects, precious few cover all of them. The authors, both pure mathematicians, have attempted to develop methods that will allow the student to formulate a given problem in a precise mathematical framework. The aim is to equip readers with a sound strategy for classifying and solving problems by pursuing a mathematically rigorous yet ...

  7. Modeling discrete competitive facility location

    CERN Document Server

    Karakitsiou, Athanasia

    2015-01-01

    This book presents an up-to-date review of modeling and optimization approaches for location problems along with a new bi-level programming methodology which captures the effect of competition of both producers and customers on facility location decisions. While many optimization approaches simplify location problems by assuming decision making in isolation, this monograph focuses on models which take into account the competitive environment in which such decisions are made. New insights in modeling, algorithmic and theoretical possibilities are opened by this approach and new applications are possible. Competition on equal term plus competition between market leader and followers are considered in this study, consequently bi-level optimization methodology is emphasized and further developed. This book provides insights regarding modeling complexity and algorithmic approaches to discrete competitive location problems. In traditional location modeling, assignment of customer demands to supply sources are made ...

  8. Discrete modelling of drapery systems

    Science.gov (United States)

    Thoeni, Klaus; Giacomini, Anna

    2016-04-01

    Drapery systems are an efficient and cost-effective measure in preventing and controlling rockfall hazards on rock slopes. The simplest form consists of a row of ground anchors along the top of the slope connected to a horizontal support cable from which a wire mesh is suspended down the face of the slope. Such systems are generally referred to as simple or unsecured draperies (Badger and Duffy 2012). Variations such as secured draperies, where a pattern of ground anchors is incorporated within the field of the mesh, and hybrid systems, where the upper part of an unsecured drapery is elevated to intercept rockfalls originating upslope of the installation, are becoming more and more popular. This work presents a discrete element framework for simulation of unsecured drapery systems and its variations. The numerical model is based on the classical discrete element method (DEM) and implemented into the open-source framework YADE (Šmilauer et al., 2010). The model takes all relevant interactions between block, drapery and slope into account (Thoeni et al., 2014) and was calibrated and validated based on full-scale experiments (Giacomini et al., 2012).The block is modelled as a rigid clump made of spherical particles which allows any shape to be approximated. The drapery is represented by a set of spherical particle with remote interactions. The behaviour of the remote interactions is governed by the constitutive behaviour of the wire and generally corresponds to a piecewise linear stress-strain relation (Thoeni et al., 2013). The same concept is used to model wire ropes. The rock slope is represented by rigid triangular elements where material properties (e.g., normal coefficient of restitution, friction angle) are assigned to each triangle. The capabilities of the developed model to simulate drapery systems and estimate the residual hazard involved with such systems is shown. References Badger, T.C., Duffy, J.D. (2012) Drapery systems. In: Turner, A.K., Schuster R

  9. Modeling biological tissue growth: discrete to continuum representations.

    Science.gov (United States)

    Hywood, Jack D; Hackett-Jones, Emily J; Landman, Kerry A

    2013-09-01

    There is much interest in building deterministic continuum models from discrete agent-based models governed by local stochastic rules where an agent represents a biological cell. In developmental biology, cells are able to move and undergo cell division on and within growing tissues. A growing tissue is itself made up of cells which undergo cell division, thereby providing a significant transport mechanism for other cells within it. We develop a discrete agent-based model where domain agents represent tissue cells. Each agent has the ability to undergo a proliferation event whereby an additional domain agent is incorporated into the lattice. If a probability distribution describes the waiting times between proliferation events for an individual agent, then the total length of the domain is a random variable. The average behavior of these stochastically proliferating agents defining the growing lattice is determined in terms of a Fokker-Planck equation, with an advection and diffusion term. The diffusion term differs from the one obtained Landman and Binder [J. Theor. Biol. 259, 541 (2009)] when the rate of growth of the domain is specified, but the choice of agents is random. This discrepancy is reconciled by determining a discrete-time master equation for this process and an associated asymmetric nonexclusion random walk, together with consideration of synchronous and asynchronous updating schemes. All theoretical results are confirmed with numerical simulations. This study furthers our understanding of the relationship between agent-based rules, their implementation, and their associated partial differential equations. Since tissue growth is a significant cellular transport mechanism during embryonic growth, it is important to use the correct partial differential equation description when combining with other cellular functions.

  10. Evaluating Number Sense in Community College Developmental Math Students

    Science.gov (United States)

    Steinke, Dorothea A.

    2017-01-01

    Community college developmental math students (N = 657) from three math levels were asked to place five whole numbers on a line that had only endpoints 0 and 20 marked. How the students placed the numbers revealed the same three stages of behavior that Steffe and Cobb (1988) documented in determining young children's number sense. 23% of the…

  11. Developmental response of tropi cal warehouse moth, Ephestia ...

    African Journals Online (AJOL)

    Developing larvae of major insect pests like Ephestia cautella rapidly degrade stored cocoa beans through feeding and other biological activities on the beans. Completion of developmental stages of insects may be influenced by a number of biochemical factors triggered by the primary post-harvest processing of cocoa ...

  12. A Discrete Spectral Problem and Related Hierarchy of Discrete Hamiltonian Lattice Equations

    International Nuclear Information System (INIS)

    Xu Xixiang; Cao Weili

    2007-01-01

    Staring from a discrete matrix spectral problem, a hierarchy of lattice soliton equations is presented though discrete zero curvature representation. The resulting lattice soliton equations possess non-local Lax pairs. The Hamiltonian structures are established for the resulting hierarchy by the discrete trace identity. Liouville integrability of resulting hierarchy is demonstrated.

  13. A new system for assessment of growth using mandibular canine calcification stages and its correlation with modified MP3 stages

    Directory of Open Access Journals (Sweden)

    Gautham Hegde

    2014-01-01

    Full Text Available Objective: Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. Materials and Methods: A total of 160 periapical radiographs, of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian′s stages of dental calcification and the modified MP3 stages. Results and Discussion: The correlation coefficient between MP3 stages and developmental stages of mandibular canine was found to be significant in both male and female groups. When the canine calcification stages were compared with the MP3 stages it was found that with the exception of the D stage of canine calcification the remaining stages showed a very high correlation with the modified MP3 stages. Conclusion: The correlation between the mandibular canine calcification stages, and the MP3 stages was found to be significant. The canine calcification could be used as a sole indicator for assessment of skeletal maturity.

  14. Geometry and Hamiltonian mechanics on discrete spaces

    International Nuclear Information System (INIS)

    Talasila, V; Clemente-Gallardo, J; Schaft, A J van der

    2004-01-01

    Numerical simulation is often crucial for analysing the behaviour of many complex systems which do not admit analytic solutions. To this end, one either converts a 'smooth' model into a discrete (in space and time) model, or models systems directly at a discrete level. The goal of this paper is to provide a discrete analogue of differential geometry, and to define on these discrete models a formal discrete Hamiltonian structure-in doing so we try to bring together various fundamental concepts from numerical analysis, differential geometry, algebraic geometry, simplicial homology and classical Hamiltonian mechanics. For example, the concept of a twisted derivation is borrowed from algebraic geometry for developing a discrete calculus. The theory is applied to a nonlinear pendulum and we compare the dynamics obtained through a discrete modelling approach with the dynamics obtained via the usual discretization procedures. Also an example of an energy-conserving algorithm on a simple harmonic oscillator is presented, and its effect on the Poisson structure is discussed

  15. Cuspidal discrete series for semisimple symmetric spaces

    DEFF Research Database (Denmark)

    Andersen, Nils Byrial; Flensted-Jensen, Mogens; Schlichtkrull, Henrik

    2012-01-01

    We propose a notion of cusp forms on semisimple symmetric spaces. We then study the real hyperbolic spaces in detail, and show that there exists both cuspidal and non-cuspidal discrete series. In particular, we show that all the spherical discrete series are non-cuspidal. (C) 2012 Elsevier Inc. All...

  16. Discrete Riccati equation solutions: Distributed algorithms

    Directory of Open Access Journals (Sweden)

    D. G. Lainiotis

    1996-01-01

    Full Text Available In this paper new distributed algorithms for the solution of the discrete Riccati equation are introduced. The algorithms are used to provide robust and computational efficient solutions to the discrete Riccati equation. The proposed distributed algorithms are theoretically interesting and computationally attractive.

  17. Painleve test and discrete Boltzmann equations

    International Nuclear Information System (INIS)

    Euler, N.; Steeb, W.H.

    1989-01-01

    The Painleve test for various discrete Boltzmann equations is performed. The connection with integrability is discussed. Furthermore the Lie symmetry vector fields are derived and group-theoretical reduction of the discrete Boltzmann equations to ordinary differentiable equations is performed. Lie Backlund transformations are gained by performing the Painleve analysis for the ordinary differential equations. 16 refs

  18. Variance Swap Replication: Discrete or Continuous?

    Directory of Open Access Journals (Sweden)

    Fabien Le Floc’h

    2018-02-01

    Full Text Available The popular replication formula to price variance swaps assumes continuity of traded option strikes. In practice, however, there is only a discrete set of option strikes traded on the market. We present here different discrete replication strategies and explain why the continuous replication price is more relevant.

  19. Discretization vs. Rounding Error in Euler's Method

    Science.gov (United States)

    Borges, Carlos F.

    2011-01-01

    Euler's method for solving initial value problems is an excellent vehicle for observing the relationship between discretization error and rounding error in numerical computation. Reductions in stepsize, in order to decrease discretization error, necessarily increase the number of steps and so introduce additional rounding error. The problem is…

  20. Discrete/PWM Ballast-Resistor Controller

    Science.gov (United States)

    King, Roger J.

    1994-01-01

    Circuit offers low switching loss and automatic compensation for failure of ballast resistor. Discrete/PWM ballast-resistor controller improved shunt voltage-regulator circuit designed to supply power from high-resistance source to low-impedance bus. Provides both coarse discrete voltage levels (by switching of ballast resistors) and continuous fine control of voltage via pulse-width modulation.