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The role of children’s verbal repetition of parents’ utterances on vocabulary growth has been well documented (Masur, 1999). Nevertheless, few studies have analyzed adults’ and children’s spontaneous verbal repetition around the second birthday distinguishing between the types of repetition. We analyzed longitudinally Spanish-speaking parent-child dyads during spontaneous interaction at 21, 24 and 30 months. Linguistic level was measured using the Spanish version of the MacArthur CDI (López-Ornat et al., 2005). Children’s and adults’ repetitions are about 17% of the speech. Children repeated adults’ utterances in a reduced manner whereas adults produced more extended repetitions. Adults’ rate of repetition predicted children’s linguistic level at 30 months. Children’s rate of repetition did not predict linguistic level. These results suggest that parents adapt their speech to children’s communicative abilities. Since children’s rate of repetition did not predict linguistic level, we suggest that verbal imitation plays an indirect and complex role in communicative development.
In most trials and systematic reviews that evaluate exercise-based interventions in reducing depressive symptoms, it is difficult to separate treatment from prevention.
To evaluate the effectiveness of exercise-based interventions in reducing depressive symptoms in people without clinical depression.
We searched PubMed, PsycINFO, Embase, WOS, SPORTDiscus, CENTRAL, OpenGrey and other sources up to 25 May 2020. We selected randomised controlled trials (RCTs) that compared exclusively exercise-based interventions with control groups, enrolling participants without clinical depression, as measured using validated instruments, and whose outcome was reduction of depressive symptoms and/or incidence of new cases of people with depression. Pooled standardised mean differences (SMDs) were calculated using random-effect models (registration at PROSPERO: CRD42017055726).
A total of 14 RCTs (18 comparisons) evaluated 1737 adults without clinical depression from eight countries and four continents. The pooled SMD was −0.34 (95% CI −0.51 to −0.17; P < 0.001) and sensitivity analyses confirmed the robustness of this result. We found no statistical evidence of publication bias and heterogeneity was moderate (I2 = 54%; 95% CI 22–73%). Only two RCTs had an overall low risk of bias and three had long-term follow-up. Multivariate meta-regression found that a larger sample size, country (Asia) and selective prevention (i.e. people exposed to risk factors for depression) were associated with lower effectiveness, although only sample size remained significant when adjustment for multiple tests was considered. According to the Grading of Recommendations Assessment, Development and Evaluation tool, the quality of evidence was low.
Exercise-based interventions have a small effect on the reduction of depressive symptoms in people without clinical depression. It could be an alternative to or complement psychological programmes, although further higher-quality trials with larger samples and long-term follow-up are needed.
This chapter provides an outlook of the issues, born out of the material presented in the book, that will likely be at the center of future developments of the field. They are organized following the scheme set by the preceding chapters.
This chapter illustrates the implications of river network structure for the spread of waterborne diseases. Human mobility is also added as a driver and a network of interaction. The water-related (WR) diseases considered are epidemic cholera, endemic schistosomiasis, and proliferative kidney disease in fish. After reviewing the basic (space-implicit) epidemiological models for micro- and micro-parasites, general space-explicit models for both kinds of parasites are studied. Both the hydrologic and the human mobility network are included, and the general conditions for disease establishment are derived, including also the case of seasonal forcings. Conditions for transient (though possibly large) epidemics are also found. The microparasitic model is applied to several cholera epidemics, including the one that has been devastating Haiti. Spatially explicit macroparasitic models of schistosomiasis are then analyzed and applied to the cases of Senegal and Burkina Faso. Proliferative kidney disease (PKD) in salmonid fish, a pathology linked to global warming, is modeled. The space-explicit approach is used for the study of PKD spread in the basin of the river Wigger (Switzerland).
Three separate appendices, rather technical, compose this chapter. The first deals with the stability of dynamical systems and bifurcation analysis, the second with a background and rationale for optimal channel networks. The third deals with computational tools: Matlab code is explained and run, and results are highlighted. The source codes may be downloaded at www.epfl.ch/labs/echo/.
The chapter explores the problem of species spread in river systems. It introduces the basic quantitative tools for dealing with the topic: first advection-diffusion-reaction traditional equations, then more modern approaches via interacting particle systems and reaction random walks on graphs. The Mississippi-Missouri river system is once again taken as the epitomizing river network: the dramatic invasion of the zebra mussel (Dreissena polymorpha), seeded by the accidental discharge of ballast water from European cargo ships in the Great Lakes region, is studied via a multilayer network model, including not only hydrology but also the displacement due to anthropic activity. Advanced laboratory experiments are then described and modeled in which the response of the alga Euglena gracilis when exposed to controlled light fields is analyzed. This allows insight into the problem of how spatial resource availability shapes the invasion patterns of riverine populations. Finally, a thorough analysis of mixing and dispersion in river systems is the basic tool to tackle a problem of enormous interest, namely, estimating species distribution and abundance using environmental DNA.
The introductory chapter outlines the leit-motiv of the book – dendritic substrates for ecological interactions, chief and foremost river networks in our case, bear important consequences for a number of processes, from patterns of biodiversity to controls of spreading of waterborne disease. In this chapter we discuss important methodological aspects of spatially explicit ecology that are used throughout the book.
The chapter is not a complete review of the subject but rather contains a specific choice of topics relevant to the general concepts of biodiversity in river networks. It first explores the fish diversity of the Mississippi-Missouri river system via a hierarchical metacommunity model that includes river hydrology and habitat suitability. Illustrated is the role of the frequency distribution of shear stresses in determining the spatially explicit probability distribution functions of benthic invertebrate habitat suitability. The viewpoint is then broadened by addressing general metapopulation persistence in river networks; this is achieved by analyzing stage-structured populations that exploit different dispersal pathways, both alongstream and overland. Examples are given with reference to amphibians. Gradients of biodiversity in fluvial landscapes, as determined by changes in elevation, is the next topic. The characteristic features of hump-shaped patterns of species richness along elevational gradients are derived, using both idealized (but realistic) fluvial landscapes and real landscapes of the Swiss Alps. The approach allows also the outline of possible consequences of climate change.
River networks are critically important ecosystems. This interdisciplinary book provides an integrated ecohydrological framework blending laboratory, field, and theoretical evidence that changes our understanding of river networks as ecological corridors. It describes how the physical structure of the river environment impacts biodiversity, species invasions, population dynamics, and the spread of waterborne disease. State-of-the-art research on the ecological roles of the structure of river networks is summarized, including important studies on the spread and control of waterborne diseases, biodiversity loss due to water resource management, and invasions by non-native species. Practical implications of this research are illustrated with numerous examples throughout. This is an invaluable go-to reference for graduate students and researchers interested in river ecology and hydrology, and the links between the two. Describing new related research on spatially-explicit modeling of the spread of waterborne disease, this book will also be of great interest to epidemiologists and public health managers.
The aim of this study was to provide a more comprehensive understanding of 1PN intracytoplasmic sperm injection (ICSI) zygotes. To achieve this objective, we assessed whether all 1PN-derived embryos showed a similar morphokinetic pattern, and if the morphokinetic behaviour of 1PN-derived embryos was comparable with that of 2PN-derived embryos. In total, 149 1PN ICSI zygotes (study group) and 195 2PN ICSI zygotes (control group) were included in the study. Embryo development potential was evaluated in terms of blastocyst rate. Morphokinetic parameters, including the pronucleus diameter and kinetics of in vitro development, were also analyzed. Embryos derived from 1PN ICSI zygotes showed impaired development compared with 2PN-derived embryos, with blastocyst rates of 28.9% and 67.2%, respectively. The diameter of the pronucleus of 1PN zygotes was larger than that of 2PN zygotes. When compared with 2PN-derived embryos, those derived from 1PN zygotes had a visible pronucleus for a shorter time, in addition to a longer syngamy time and slower kinetic behaviour from two to nine cells. When 1PN-derived blastocysts and 2PN-derived blastocysts were compared, the developmental kinetics were similar in both groups, except for a delayed and longer duration of the compaction phase in 1PN-derived embryos. In conclusion, monopronucleated ICSI zygotes present differences in developmental capacity and morphokinetic behaviour compared with 2PN ICSI zygotes, showing particular morphokinetic parameters related to pronucleus formation. Only the 1PN ICSI-derived embryos that reached the blastocyst stage have similar morphokinetic development to blastocysts from 2PN zygotes.
The authors prepared a micro-structured, thermosensitive hydrogel with N-isopropylacrylamide microgels with a lower critical solution temperature (LCST) of 32 °C dispersed on a matrix of N-isopropylacrylamide-co-dimethylacrylamide with an LCST at 40 °C. Incubation of the hydrogel at 33 °C in a solution of fluorescein-albumin induced loading of the protein. The protein was not loaded at a temperature below the LCST of the microgels (4 °C), suggesting that the shrinkage of the microgels followed by the formation of micropores within the hydrogel matrix is a prerequisite for protein loading. A sustained and complete release of the loaded protein was obtained at 37 °C.
This study examined (1) the association of dietary energy density from solid (EDS) and solid plus liquids (EDSL) with adiposity and cardiometabolic risk factors (CRF) in children with overweight and obesity, (2) the effect of under-reporting on the mentioned associations and (3) whether the association between ED and body composition and CRF is influenced by levels of physical activity. In a cross-sectional design, 208 overweight and obese children (8–12-year-old; 111 boys) completed two non-consecutive 24 h recalls. ED was calculated using two different approaches: EDS and EDSL. Under-reporters were determined with the Goldberg method. Body composition, anthropometry and fasting blood sample measurements were performed. Moderate to vigorous physical activity (MVPA) was registered with accelerometers (7-d-register). Linear regressions were performed to evaluate the association of ED with the previously mentioned variables. Neither EDS nor EDSL were associated with body composition or CRF. However, when under-reporters were excluded, EDS was positively associated with BMI (P=0·019), body fat percentage (P=0·005), abdominal fat (P=0·008) and fat mass index (P=0·018), while EDSL was positively associated with body fat percentage (P=0·008) and fat mass index (P=0·026). When stratifying the group according to physical activity recommendations, the aforementioned associations were only maintained for non-compliers. Cluster analysis showed that the low-ED and high-MVPA group presented the healthiest profile for all adiposity and CRF. These findings could partly explain inconsistencies in literature, as we found that different ED calculations entail distinct results. Physical activity levels and excluding under-reporters greatly influence the associations between ED and adiposity in children with overweight and obesity.