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81.
Although number words are common in everyday speech, learning their meanings is an arduous, drawn-out process for most children, and the source of this delay has long been the subject of inquiry. Children begin by identifying the few small numerosities that can be named without counting, and this has prompted further debate over whether there is a specific, capacity-limited system for representing these small sets, or whether smaller and larger sets are both represented by the same system. Here we present a formal, computational analysis of number learning that offers a possible solution to both puzzles. This analysis indicates that once the environment and the representational demands of the task of learning to identify sets are taken into consideration, a continuous system for learning, representing and discriminating set-sizes can give rise to effective discontinuities in processing. At the same time, our simulations illustrate how typical prenominal linguistic constructions ("there are three balls") structure information in a way that is largely unhelpful for discrimination learning, while suggesting that postnominal constructions ("balls, there are three") will facilitate such learning. A training-experiment with three-year olds confirms these predictions, demonstrating that rapid, significant gains in numerical understanding and competence are possible given appropriately structured postnominal input. Our simulations and results reveal how discrimination learning tunes children's systems for representing small sets, and how its capacity-limits result naturally out of a mixture of the learning environment and the increasingly complex task of discriminating and representing ever-larger number sets. They also explain why children benefit so little from the training that parents and educators usually provide. Given the efficacy of our intervention, the ease with which it can be implemented, and the large body of research showing how early numerical ability predicts later educational outcomes, this simple discovery may have far-reaching consequences. 相似文献
82.
Shuying Sun Zhengyi Chen Pearlly S Yan Yi-Wen Huang Tim HM Huang Shili Lin 《BMC bioinformatics》2011,12(1):54
Background
DNA methylation has been shown to play an important role in the silencing of tumor suppressor genes in various tumor types. In order to have a system-wide understanding of the methylation changes that occur in tumors, we have developed a differential methylation hybridization (DMH) protocol that can simultaneously assay the methylation status of all known CpG islands (CGIs) using microarray technologies. A large percentage of signals obtained from microarrays can be attributed to various measurable and unmeasurable confounding factors unrelated to the biological question at hand. In order to correct the bias due to noise, we first implemented a quantile regression model, with a quantile level equal to 75%, to identify hypermethylated CGIs in an earlier work. As a proof of concept, we applied this model to methylation microarray data generated from breast cancer cell lines. However, we were unsure whether 75% was the best quantile level for identifying hypermethylated CGIs. In this paper, we attempt to determine which quantile level should be used to identify hypermethylated CGIs and their associated genes. 相似文献83.
Robin Whittemore Ariana Chao Rachel Popick Margaret Grey 《The Yale journal of biology and medicine》2013,86(1):49-62
In response to the childhood obesity epidemic, numerous studies on school-basedInternet obesity prevention interventions have been conducted. The purpose ofthis systematic review is to describe, synthesize, and evaluate the research onschool-based Internet obesity prevention programs for adolescents. Medline,CINAHL, and PsycInfo were searched from January 1995 to August 2012 to locaterelevant studies. Ninety-one reports were initially identified, with 12 meetingthe inclusion criteria. Studies had variable control groups, program content,and sample characteristics. Though few authors reported on implementationprocesses or body mass index (BMI) outcomes, the majority of studies wereeffective in improving health behaviors in the short term. Most studies werejudged to have a high or unclear risk of bias in at least two domains, thus thequality of evidence for this body of literature is moderate. Further research isneeded to examine programs of longer duration, optimal dose and timing ofprograms, cost-effectiveness, and mediators and moderators of interventionoutcomes. 相似文献
84.
Julieta Ramos-Elorduy José MP Moreno Adolfo I Vázquez Ivonne Landero Héctor Oliva-Rivera Víctor HM Camacho 《Journal of ethnobiology and ethnomedicine》2011,7(1):1-22
In this paper, we reported the butterflies and moths that are consumed in Mexico. We identified 67 species of Lepidoptera that are eaten principally in their larval stage in 17 states of Mexico. These species belong to 16 families: Arctiidae, Bombycidae, Castniidae, Cossidae, Geometridae, Hepialidae, Hesperiidae, Lasiocampidae, Noctuidae, Nymphalidae, Papilionidae, Pieridae, Pyralidae, Saturniidae, Sesiidae, and Sphingidae. Saturniidae, Pieridae, Noctuidae and Nymphalidae were the more species consumed with 16, 11, 9, and 8 species, respectively. The genera with the largest numbers of species were: Phassus, Phoebis, Hylesia and Spodoptera, with three species. Their local distribution, corresponding to each state of Mexico, is also presented. 相似文献
85.
Azza M. Elamir Olfat G. Shaker Mohamed HM. El-Komy Mai Mahmoud sharabi Nesreen M. Aboraia 《Biochemistry and Biophysics Reports》2021
BackgroundPsoriasis is a chronic skin disorder manifested by recurrent episodes of scaly, red, itchy skin patches that occur within apparently normal skin.ObjectivesThis study was performed to detect the expression of serum and tissue (lesion and non-lesion) LncRNA MALAT-1 and MiRNA-9 that might be used as biomarkers for psoriasis.MethodsBlood samples were obtained from 60 psoriasis patients and 40 controls, as well as 4 mm punch biopsy from lesional and non lesional skin of psoriatic patient and normal skin of healthy controls. Expression of LncRNA MALAT-1 and miRNNA-9 in serum and tissues was detected by real time qRT-PCR.Resultsa statistically significant increase in the expression of MALAT-1 in lesional and non-lesional skin and serum of psoriatic patients in comparison to controls were detected. Moreover, there was statistically significant increase in serum MiRNA-9 in patients in comparison to controls, while its tissue level was significantly lower in patients.ConclusionThis study highlights the dysregulation of LncRNA MALAT-1 and miRNA-9 in psoriasis. Elevated expression of MALAT-1 in lesional skin of psoriatic patients compared to non-lesional skin may possibly contribute to the development of psoriatic plaques. 相似文献
86.
87.
Michelle I Portugal Adriane R Todeschini Cristiana S de Lima Carlos AM Silva Ronaldo Mohana-Borges Tom HM Ottenhoff Lucia Mendonça-Previato Jose O Previato Maria CV Pessolani 《BMC microbiology》2008,8(1):75
Background
The histone-like Hlp protein is emerging as a key component in mycobacterial pathogenesis, being involved in the initial events of host colonization by interacting with laminin and glycosaminoglycans (GAGs). In the present study, nuclear magnetic resonance (NMR) was used to map the binding site(s) of Hlp to heparan sulfate and identify the nature of the amino acid residues directly involved in this interaction. 相似文献88.
Jennifer H Humphreys Jessica AB van Nies Jackie Chipping Tarnya Marshall Annette HM van der Helm-van Mil Deborah PM Symmons Suzanne MM Verstappen 《Arthritis research & therapy》2014,16(6)
Introduction
This study aimed to investigate rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) status and levels as predictors of mortality in two large cohorts of patients with early inflammatory arthritis (EIA).Methods
Data from the Norfolk Arthritis Register (NOAR) and Leiden Early Arthritis Clinic (EAC) cohorts were used. At baseline, patients had demographic data and smoking status recorded; RF, ACPA and inflammatory markers were measured in the local laboratories. Patients were flagged with national death registers until death or censor date. Antibody status was stratified as negative, low or high positive by RF and ACPA levels individually. In addition, patients were grouped as seronegative, RF positive, ACPA positive or double antibody (RF and ACPA) positive. Cox regression models explored associations between antibody status and mortality adjusting for age, sex, smoking status, inflammatory markers and year of enrolment.Results
A total of 4962 patients were included, 64% were female. Median age at onset was 56 (NOAR) and 54 (EAC) years. In NOAR and EAC respectively, 35% and 42% of patients were ACPA/RF positive. When antibody status was stratified as negative, low or high positive, there were no consistent findings between the two cohorts. Double antibody positivity was associated with excess mortality in both cohorts compared to seronegative patients: NOAR and EAC respective adjusted HR (95% confidence interval) 1.35 (1.09 to 1.68) and 1.58 (1.16 to 2.15).Conclusions
Patients with EIA who are seropositive for both RF and ACPA have increased mortality compared to those who are single positive or seronegative. Antibody level in seropositive patients was not consistently associated with excess mortality.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0483-3) contains supplementary material, which is available to authorized users. 相似文献89.
Jessica AB van Nies Celina Alves Audrey LS Radix-Bloemen Cécile Gaujoux-Viala Tom WJ Huizinga Johanna MW Hazes Elisabeth Brouwer Bruno Fautrel Annette HM van der Helm-van Mil 《Arthritis research & therapy》2015,17(1)
IntroductionMorning stiffness is assessed daily in the diagnostic process of arthralgia and arthritis, but large-scale studies on the discriminative ability are absent. This study explored the diagnostic value of morning stiffness in 5,202 arthralgia and arthritis patients and the prognostic value in early rheumatoid arthritis (RA).MethodsIn arthralgia patients referred to the Early Arthritis Recognition Clinics (EARC) of Leiden (n = 807) and Groningen (n = 481) or included in the Rotterdam Early Arthritis Cohort (REACH) study (n = 353), the associations (cross-sectional analyses) between morning stiffness and presence of arthritis at physical examination were studied. In early arthritis patients, included in the Leiden Early Arthritis Clinic (EAC) (n = 2,748) and Evaluation et Suivi de POlyarthrites Indifférenciées Récentes (ESPOIR) (n = 813), associations with fulfilling the 2010-RA criteria after one year were assessed. In 2010-RA patients included in the EAC (n = 1,140) and ESPOIR (n = 677), association with the long-term outcomes of disease-modifying antirheumatic drug (DMARD)-free sustained remission and radiological progression were determined. Morning stiffness was defined as a duration ≥60 minutes; sensitivity analyses were performed for other definitions.ResultsIn arthralgia, morning stiffness (≥60 minutes) associated with the presence of arthritis; Leiden EARC odds ratio (OR) 1.49 (95% CI 1.001 to 2.20), Groningen EARC OR 2.21 (1.33 to 3.69) and REACH OR 1.55 (0.97 to 2.47) but the areas under the receiver operating characteristic curve (AUCs) were low (0.52, 0.57, 0.54). In early arthritis, morning stiffness was associated with 2010-RA independent of other predictors (Leiden EAC OR 1.72 (95% CI 1.31 to 2.25, AUC 0.68), ESPOIR OR 1.68 (1.03 to 2.74, AUC 0.64)). Duration of ≥30 minutes provided optimal discrimination for RA in early arthritis. Morning stiffness was not associated with radiological progression or DMARD-free sustained remission.ConclusionsMorning stiffness in arthralgia and early arthritis is associated with arthritis and RA respectively. This supports the incorporation of morning stiffness in the diagnostic process.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0616-3) contains supplementary material, which is available to authorized users. 相似文献90.
Bjorn?WH?van Heumen Hennie?MJ?Roelofs René?HM?te Morsche Fokko?M?Nagengast Wilbert?HM?PetersEmail author 《Orphanet journal of rare diseases》2013,8(1):181