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11.

Background

In Norway, a disproportionately high number of children receiving Child Welfare Services (CWS) struggle academically and drop out of school. Academic attainment is one of the strongest protective factors against societal marginalization. The present study is part of a knowledge translation project in collaboration with local CWS with the aim to develop, implement, and evaluate Enhanced Academic Support (EAS) for primary school children in CWS.

Methods/design

The study is a mixed-methods hybrid type 2 randomized, controlled pragmatic trial. The participants are approximately 120 children whose families receive support measures from three child welfare agencies in and around Oslo, Norway, and practitioners from these agencies. Families are randomly assigned to either the EAS condition or “business as usual” support. Primary outcomes are math and reading skills, parental involvement in school, and intervention fidelity. Questionnaires and academic tests are administered at baseline, post-intervention (after 6 months), and at follow-up (after 12 months). Implementation drivers are assessed before and after the trial period, and intervention fidelity is monitored during the trial through checklists and structured telephone interviews. Semi-structured interviews and focus groups are conducted after the trial.

Discussion

This hybrid study has two implications. (1) The effects of providing EAS to children in child welfare will be investigated. The study also explores how each core component of the intervention and the use of specific adaptations, implementation drivers, and other important child-level covariates moderate the overall effects. The results can provide valuable knowledge about how to deliver precise and effective academic support to increase academic skills and prevent dropout. In turn, this can promote academic completion and well-being, outcomes that are beneficial for both children and society at large. (2) The study also evaluates the feasibility of applying an Integrated Knowledge Translation model designed to develop, implement, and evaluate research-supported practice in health, care, and welfare services in less time than is usually the case. If deemed successful, this model will provide an efficient collaborative approach to translate the best available evidence into effective evidence-based practice, applicable in effectiveness research and quality improvement efforts.

Trial registration

ISRCTN, ISRCTN38968073. Registered on 18 September 2017.  https://doi.org/10.1186/ISRCTN38968073.
  相似文献   
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Fixatives used for preservation of marine fish eggs must maintain the structural integrity of eggs in order to secure determination of developmental stages. Formalin is commonly used as a fixative, however, this compound is associated with health issues, and fish eggs fixated in formalin are often not stageable after longer storage. The present study shows that 5% acidic Lugol’s solution is an efficient fixative for ichtyoplankton, and superior to formalin fixation. Flounder eggs retained their structure and staging was easy even after 1 year of storage in acidic Lugol’s solution.  相似文献   
14.
In macroscopic dynamic models of fermentation processes, elementary modes (EM) derived from metabolic networks are often used to describe the reaction stoichiometry in a simplified manner and to build predictive models by parameterizing kinetic rate equations for the EM. In this procedure, the selection of a set of EM is a key step which is followed by an estimation of their reaction rates and of the associated confidence bounds. In this paper, we present a method for the computation of reaction rates of cellular reactions and EM as well as an algorithm for the selection of EM for process modeling. The method is based on the dynamic metabolic flux analysis (DMFA) proposed by Leighty and Antoniewicz (2011, Metab Eng, 13(6), 745–755) with additional constraints, regularization and analysis of uncertainty. Instead of using estimated uptake or secretion rates, concentration measurements are used directly to avoid an amplification of measurement errors by numerical differentiation. It is shown that the regularized DMFA for EM method is significantly more robust against measurement noise than methods using estimated rates. The confidence intervals for the estimated reaction rates are obtained by bootstrapping. For the selection of a set of EM for a given st oichiometric model, the DMFA for EM method is combined with a multiobjective genetic algorithm. The method is applied to real data from a CHO fed-batch process. From measurements of six fed-batch experiments, 10 EM were identified as the smallest subset of EM based upon which the data can be described sufficiently accurately by a dynamic model. The estimated EM reaction rates and their confidence intervals at different process conditions provide useful information for the kinetic modeling and subsequent process optimization.  相似文献   
15.
Ice premelting during differential scanning calorimetry   总被引:1,自引:0,他引:1       下载免费PDF全文
PW Wilson  JW Arthur    AD Haymet 《Biophysical journal》1999,77(5):2850-2855
Premelting at the surface of ice crystals is caused by factors such as temperature, radius of curvature, and solute composition. When polycrystalline ice samples are warmed from well below the equilibrium melting point, surface melting may begin at temperatures as low as -15 degrees C. However, it has been reported (. Biophys. J. 65:1853-1865) that when polycrystalline ice was warmed in a differential scanning calorimetry (DSC) pan, melting began at about -50 degrees C, this extreme behavior being attributed to short-range forces. We show that there is no driving force for such premelting, and that for pure water samples in DSC pans curvature effects will cause premelting typically at just a few degrees below the equilibrium melting point. We also show that the rate of warming affects the slope of the DSC baseline and that this might be incorrectly interpreted as an endotherm. The work has consequences for DSC operators who use water as a standard in systems where subfreezing runs are important.  相似文献   
16.

Introduction

The aims of these studies were to identify the cytokine and chemokine expression profile of nucleus pulposus (NP) cells and to determine the relationships between NP cell cytokine and chemokine production and the characteristic tissue changes seen during intervertebral disc (IVD) degeneration.

Methods

Real-time q-PCR cDNA Low Density Array (LDA) was used to investigate the expression of 91 cytokine and chemokine associated genes in NP cells from degenerate human IVDs. Further real-time q-PCR was used to investigate 30 selected cytokine and chemokine associated genes in NP cells from non-degenerate and degenerate IVDs and those from IVDs with immune cell infiltrates (‘infiltrated’). Immunohistochemistry (IHC) was performed for four selected cytokines and chemokines to confirm and localize protein expression in human NP tissue samples.

Results

LDA identified the expression of numerous cytokine and chemokine associated genes including 15 novel cytokines and chemokines. Further q-PCR gene expression studies identified differential expression patterns in NP cells derived from non-degenerate, degenerate and infiltrated IVDs. IHC confirmed NP cells as a source of IL-16, CCL2, CCL7 and CXCL8 and that protein expression of CCL2, CCL7 and CXCL8 increases concordant with histological degenerative tissue changes.

Conclusions

Our data indicates that NP cells are a source of cytokines and chemokines within the IVD and that these expression patterns are altered in IVD pathology. These findings may be important for the correct assessment of the ‘degenerate niche’ prior to autologous or allogeneic cell transplantation for biological therapy of the degenerate IVD.  相似文献   
17.
Peatlands contain approximately one third of all soil organic carbon (SOC). Warming can alter above‐ and belowground linkages that regulate soil organic carbon dynamics and C‐balance in peatlands. Here we examine the multiyear impact of in situ experimental warming on the microbial food web, vegetation, and their feedbacks with soil chemistry. We provide evidence of both positive and negative impacts of warming on specific microbial functional groups, leading to destabilization of the microbial food web. We observed a strong reduction (70%) in the biomass of top‐predators (testate amoebae) in warmed plots. Such a loss caused a shortening of microbial food chains, which in turn stimulated microbial activity, leading to slight increases in levels of nutrients and labile C in water. We further show that warming altered the regulatory role of Sphagnum‐polyphenols on microbial community structure with a potential inhibition of top predators. In addition, warming caused a decrease in Sphagnum cover and an increase in vascular plant cover. Using structural equation modelling, we show that changes in the microbial food web affected the relationships between plants, soil water chemistry, and microbial communities. These results suggest that warming will destabilize C and nutrient recycling of peatlands via changes in above‐ and belowground linkages, and therefore, the microbial food web associated with mosses will feedback positively to global warming by destabilizing the carbon cycle. This study confirms that microbial food webs thus constitute a key element in the functioning of peatland ecosystems. Their study can help understand how mosses, as ecosystem engineers, tightly regulate biogeochemical cycling and climate feedback in peatlands  相似文献   
18.
The effect of various levels of nitrogen (0.0, 30.0, 60.0, 120.0) and phosphorus (0.0, 6.5, 13.0, 36.0) on the incidence and severity of downy mildew of pearl millet and yield of two pearl millet varieties (Zango and GB8375) were studied under field conditions in 2000 and 2001 respectively. Both nitrogen and phosphorus significantly increased incidence and severity of the disease in the two varieties. Grain yield and 1000 grain weight of the varieties also increased with nitrogen and phosphorus levels.  相似文献   
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20.

Background  

The relaxin-like peptide family belongs in the insulin superfamily and consists of 7 peptides of high structural but low sequence similarity; relaxin-1, 2 and 3, and the insulin-like (INSL) peptides, INSL3, INSL4, INSL5 and INSL6. The functions of relaxin-3, INSL4, INSL5, INSL6 remain uncharacterised. The evolution of this family has been contentious; high sequence variability is seen between closely related species, while distantly related species show high similarity; an invertebrate relaxin sequence has been reported, while a relaxin gene has not been found in the avian and ruminant lineages.  相似文献   
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