1,271 research outputs found

    Dynamics of adolescents' smartphone use and well-being are positive but ephemeral

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    Well-being and smartphone use are thought to influence each other. However, previous studies mainly focused on one direction (looking at the effects of smartphone use on well-being) and considered between-person effects, with self-reported measures of smartphone use. By using 2548 assessments of well-being and trace data of smartphone use collected for 45 consecutive days in 82 adolescent participants (Mage_{age} = 13.47, SDage_{age} = 1.62, 54% females), the present study disentangled the reciprocal and individual dynamics of well-being and smartphone use. Hierarchical Bayesian Continuous Time Dynamic Models were used to estimate how a change in frequency and duration of smartphone use predicted a later change in well-being, and vice versa. Results revealed that (i) when participants used the smartphone frequently and for a longer period, they also reported higher levels of well-being; (ii) well-being positively predicted subsequent duration of smartphone use; (iii) usage patterns and system dynamics showed heterogeneity, with many subjects showing reciprocal effects close to zero; finally, (iv) changes in well-being tend to persist longer than changes in the frequency and duration of smartphone use

    Essential Oils and their Antimicrobial Effect on Serratia Marcescens

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    S. marcescens is a gram-negative, facultatively anaerobic bacterium that is particularly aggressive in its growing capability. It is a concern in medical fields as well as home environments due to its resistance to most antibiotics, high mortality rate, and easy ability to colonize on soap and other fatty substances. Although testing of natural cleansers such as lemon juice, vinegar, and ammonia has been done on S. marcescens and essential oil efficacy has been tested on Escherichia coli and Staphylococcus aureus, no literature has been published on the effect of essential oils on S. marcescens growth. The purpose of this experiment therefore was to test the efficiency of essential oils in inhibiting the growth of this bacterium. Using Kirby-Bauer Assay and Minimum Inhibitory Concentration testing we compared the effectiveness of different harsh cleaners such as LysolÂź, with peppermint and helichrysum essential oils. Although few significant values were obtained, noticeable zones of inhibition were seen, especially for peppermint oil. Based on this finding, further research should be done exploring this potency of peppermint and other essential oils on S. marcescens

    A focus on critical aspects of uptake and transport of milk-derived extracellular vesicles across the Caco-2 intestinal barrier model

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    Bovine milk-derived extracellular vesicles (EVs) hold promises as oral drug delivery systems. Since EV bioavailability studies are difficult to compare, key factors regarding EV uptake and intestinal permeability remain little understood. This work aims to critically study uptake and transport properties of milk-derived EVs across the intestinal barrier in vitro by standardization approaches. Therefore, uptake properties were directly compared to liposomes in intestinal Caco-2 cells. Reliable staining results were obtained by the choice of three distinct EV labeling sites, while non-specific dye transfer and excess dye removal were carefully controlled. A novel fluorescence correction factor was implemented to account for different labelling efficiencies. Both EV and liposome uptake occurred mainly energy dependent with the neonatal Fc receptor (FcRn) providing an exclusive active pathway for EVs. Confocal microscopy revealed higher internalization of EVs whereas liposomes rather remained attached to the cell surface. Internalization could be improved when changing the liposomal formulation to resemble the EV lipid composition. In a Caco-2/HT29-MTX co-culture liposomes and EVs showed partial mucus penetration. For transport studies across Caco-2 monolayers we further established a standardized protocol considering the distinct requirements for EVs. Especially insert pore sizes were systematically compared with 3 ”m inserts found obligatory. Obtained apparent permeability coefficients (Papp) reflecting the transport rate will allow for better comparison of future bioavailability testing

    The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials

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    Flaws in the design, conduct, analysis, and reporting of randomised trials can cause the effect of an intervention to be underestimated or overestimated. The Cochrane Collaboration’s tool for assessing risk of bias aims to make the process clearer and more accurat

    Branch point strength controls species-specific CAMK2B alternative splicing and regulates LTP

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    Regulation and functionality of species-specific alternative splicing has remained enigmatic to the present date. Calcium/calmodulin-dependent protein kinase IIÎČ (CaMKIIÎČ) is expressed in several splice variants and plays a key role in learning and memory. Here, we identify and characterize several primate-specific CAMK2B splice isoforms, which show altered kinetic properties and changes in substrate specificity. Furthermore, we demonstrate that primate-specific CAMK2B alternative splicing is achieved through branch point weakening during evolution. We show that reducing branch point and splice site strengths during evolution globally renders constitutive exons alternative, thus providing novel mechanistic insight into cis-directed species-specific alternative splicing regulation. Using CRISPR/Cas9, we introduce a weaker, human branch point sequence into the mouse genome, resulting in strongly altered Camk2b splicing in the brains of mutant mice. We observe a strong impairment of long-term potentiation in CA3-CA1 synapses of mutant mice, thus connecting branch point–controlled CAMK2B alternative splicing with a fundamental function in learning and memory

    Mind the Gap: Investigating Toddlers’ Sensitivity to Contact Relations in Predictive Events

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    Toddlers readily learn predictive relations between events (e.g., that event A predicts event B). However, they intervene on A to try to cause B only in a few contexts: When a dispositional agent initiates the event or when the event is described with causal language. The current studies look at whether toddlers’ failures are due merely to the difficulty of initiating interventions or to more general constraints on the kinds of events they represent as causal. Toddlers saw a block slide towards a base, but an occluder prevented them from seeing whether the block contacted the base; after the block disappeared behind the occluder, a toy connected to the base did or did not activate. We hypothesized that if toddlers construed the events as causal, they would be sensitive to the contact relations between the participants in the predictive event. In Experiment 1, the block either moved spontaneously (no dispositional agent) or emerged already in motion (a dispositional agent was potentially present). Toddlers were sensitive to the contact relations only when a dispositional agent was potentially present. Experiment 2 confirmed that toddlers inferred a hidden agent was present when the block emerged in motion. In Experiment 3, the block moved spontaneously, but the events were described either with non-causal (“here’s my block”) or causal (“the block can make it go”) language. Toddlers were sensitive to the contact relations only when given causal language. These findings suggest that dispositional agency and causal language facilitate toddlers’ ability to represent causal relationships.John Templeton Foundation (#12667)James S. McDonnell Foundation (Causal Learning Collaborative Initiative)National Science Foundation (U.S.) (Career Award (# 0744213

    Consolidated standards of reporting trials (CONSORT) and the completeness of reporting of randomised controlled trials (RCTs) published inmedical journals (Review)

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    Background: An overwhelming body of evidence stating that the completeness of reporting of randomised controlled trials (RCTs) is not optimal has accrued over time. In the mid-1990s, in response to these concerns, an international group of clinical trialists, statisticians, epidemiologists, and biomedical journal editors developed the CONsolidated Standards Of Reporting Trials (CONSORT) Statement. The CONSORT Statement, most recently updated in March 2010, is an evidence-based minimum set of recommendations including a checklist and flow diagram for reporting RCTs and is intended to facilitate the complete and transparent reporting of trials and aid their critical appraisal and interpretation. In 2006, a systematic review of eight studies evaluating the “effectiveness of CONSORT in improving reporting quality in journals” was published. Objectives: To update the earlier systematic review assessing whether journal endorsement of the 1996 and 2001 CONSORT checklists influences the completeness of reporting of RCTs published in medical journals. Search methods: We conducted electronic searches, known item searching, and reference list scans to identify reports of evaluations assessing the completeness of reporting of RCTs. The electronic search strategy was developed inMEDLINE and tailored to EMBASE.We searched the Cochrane Methodology Register and the Cochrane Database of Systematic Reviews using the Wiley interface. We searched the Science Citation Index, Social Science Citation Index, and Arts and Humanities Citation Index through the ISI Web of Knowledge interface. We conducted all searches to identify reports published between January 2005 and March 2010, inclusive. Selection criteria: In addition to studies identified in the original systematic review on this topic, comparative studies evaluating the completeness of reporting of RCTs in any of the following comparison groups were eligible for inclusion in this review: 1) Completeness of reporting of RCTs published in journals that have and have not endorsed the CONSORT Statement; 2) Completeness of reporting of RCTs published in CONSORT-endorsing journals before and after endorsement; or 3) Completeness of reporting of RCTs before and after the publication of the CONSORT Statement (1996 or 2001). We used a broad definition of CONSORT endorsement that includes any of the following: (a) requirement or recommendation in journal’s ’Instructions to Authors’ to follow CONSORT guidelines; (b) journal editorial statement endorsing the CONSORT Statement; or (c) editorial requirement for authors to submit a CONSORT checklist and/or flow diagram with their manuscript. We contacted authors of evaluations reporting data that could be included in any comparison group(s), but not presented as such in the published report and asked them to provide additional data in order to determine eligibility of their evaluation. Evaluations were not excluded due to language of publication or validity assessment. Data collection and analysis: We completed screening and data extraction using standardised electronic forms, where conflicts, reasons for exclusion, and level of agreement were all automatically and centrally managed in web-based management software, DistillerSR¼. One of two authors extracted general characteristics of included evaluations and all data were verified by a second author. Data describing completeness of reporting were extracted by one author using a pre-specified form; a 10%random sample of evaluations was verified by a second author. Any discrepancies were discussed by both authors; we made no modifications to the extracted data. Validity assessments of included evaluations were conducted by one author and independently verified by one of three authors. We resolved all conflicts by consensus. For each comparison we collected data on 27 outcomes: 22 items of the CONSORT 2001 checklist, plus four items relating to the reporting of blinding, and one item of aggregate CONSORT scores. Where reported, we extracted and qualitatively synthesised data on the methodological quality of RCTs, by scale or score. Main results: Fifty-three publications reporting 50 evaluations were included. The total number of RCTs assessed within evaluations was 16,604 (median per evaluation 123 (interquartile range (IQR) 77 to 226) published in a median of six (IQR 3 to 26) journals. Characteristics of the included RCT populations were variable, resulting in heterogeneity between included evaluations. Validity assessments of included studies resulted in largely unclear judgements. The included evaluations are not RCTs and less than 8% (4/53) of the evaluations reported adjusting for potential confounding factors. Twenty-five of 27 outcomes assessing completeness of reporting in RCTs appeared to favour CONSORT-endorsing journals over non-endorsers, of which five were statistically significant. ’Allocation concealment’ resulted in the largest effect, with risk ratio (RR) 1.81 (99% confidence interval (CI) 1.25 to 2.61), suggesting that 81% more RCTs published in CONSORT-endorsing journals adequately describe allocation concealment compared to those published in non-endorsing journals. Allocation concealment was reported adequately in 45% (393/876) of RCTs in CONSORT-endorsing journals and in 22% (329/1520) of RCTs in non-endorsing journals. Other outcomes with results that were significant include: scientific rationale and background in the ’Introduction’ (RR 1.07, 99% CI 1.01 to 1.14); ’sample size’ (RR 1.61, 99% CI 1.13 to 2.29); method used for ’sequence generation’ (RR 1.59, 99% CI 1.38 to 1.84); and an aggregate score over reported CONSORT items, ’total sum score’ (standardised mean difference (SMD) 0.68 (99% CI 0.38 to 0.98)). Authors’ conclusions: Evidence has accumulated to suggest that the reporting of RCTs remains sub-optimal. This review updates a previous systematic review of eight evaluations. The findings of this review are similar to those from the original review and demonstrate that, despite the general inadequacies of reporting of RCTs, journal endorsement of the CONSORT Statement may beneficially influence the completeness of reporting of trials published in medical journals. Future prospective studies are needed to explore the influenc

    The State of the Dark Energy Equation of State

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    By combining data from seven cosmic microwave background experiments (including the latest WMAP results) with large scale structure data, the Hubble parameter measurement from the Hubble Space Telescope and luminosity measurements of Type Ia supernovae we demonstrate the bounds on the dark energy equation of state wQw_Q to be −1.38<wQ<−0.82-1.38< w_Q <-0.82 at the 95% confidence level. Although our limit on wQw_Q is improved with respect to previous analyses, cosmological data does not rule out the possibility that the equation of state parameter wQw_Q of the dark energy QQ is less than -1. We present a tracking model that ensures wQ≀−1w_Q \le -1 at recent times and discuss the observational consequences.Comment: 7 pages, 4 figures, added a referenc
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