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OBJECTIVES: Reporting bias, prevalent in biomedical fields, can undermine evidence credibility. Our objective was to evaluate the proportion of discrepancies between registered protocols and published manuscripts in randomized controlled trials (RCTs) on exercise interventions for patients with chronic low back pain (CLBP). STUDY DESIGN AND SETTING: We conducted a cross-sectional meta-research study, starting from the 2021 "Exercise therapy for CLBP" Cochrane Review. We selected all RCTs reporting a protocol registration on a primary register of the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) or in ClinicalTrials.gov. We extracted data from both registered protocol and published manuscript of RCTs, collecting recruitment and administrative information (eg, record dates) and details of trial characteristics (eg, outcomes, arms, statistical analysis plan details [SAPs]). Independent pairs of reviewers assessed discrepancies between registered protocol and published manuscript for the reporting of primary and secondary outcomes domains, measurement instruments, time-points, number of arms and SAPs(if attached). Outcome discrepancies were characterized as addition, omission, upgrade or downgrade. RESULTS: We included 116 RCTs reporting an available protocol registration. Overall, 100 RCTs (86.2%) distinguished between primary and secondary outcomes. Of these, 39 RCTs (39.0%) reported one or more discrepancies in primary outcomes, and 78 RCTs (78.0%) reported one or more discrepancies in secondary outcomes. Focusing on discrepancies for the primary outcome, 64.5% of added, upgraded or downgraded outcomes favored statistically significant effects. Few RCTs (n = 6) reported discrepancies in the number of arms. SAPs were poorly reported in the registered protocols (n = 3) for being compared to the publications. CONCLUSION: We found substantial outcome discrepancies comparing registered protocols and published manuscripts in RCTs assessing exercise interventions for patients with CLBP, with some impacting the statistical significance of the effects. Readers are encouraged to approach RCTs results in this field with caution.
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The integration of microalgae cultivation in anaerobic digestion (AD) plants can take advantage of relevant nutrients (ammonium and ortho-phosphate) and CO2 loads. The proposed scheme of microalgae integration in existing biogas plants aims at producing approximately 250 t·y-1 of microalgal biomass, targeting the biostimulants market that is currently under rapid expansion. A full-scale biorefinery was designed to treat 50 kt·y-1 of raw liquid digestate from AD and 0.45 kt·y-1 of CO2 from biogas upgrading, and 0.40 kt·y-1 of sugar-rich solid by-products from a local confectionery industry. An innovative three-stage cultivation process was designed, modelled, and verified, including: i) microalgae inoculation in tubular PBRs to select the desired algal strains, ii) microalgae cultivation in raceway ponds under greenhouses, and iii) heterotrophic microalgae cultivation in fermenters. A detailed economic assessment of the proposed biorefinery allowed to compute a biomass production cost of 2.8 ± 0.3 ·kg DW-1, that is compatible with current downstream process costs to produce biostimulants, suggesting that the proposed nutrient recovery route is feasible from the technical and economic perspective. Based on the case study analysis, a discussion of process, bioproducts and policy barriers that currently hinder the development of microalgae-based biorefineries is presented.
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The visualization of metabolic flux in real time requires sensor molecules that transduce variations of metabolite concentrations into an appropriate output signal. In this regard, fluorogenic RNA-based biosensors are promising molecular tools as they fluoresce only upon binding to another molecule. However, to date no such sensor is available that enables the direct observation of key metabolites in mammalian cells. Toward this direction, we selected and characterized an RNA light-up sensor designed to respond to fructose 1,6-bisphosphate and applied it to probe glycolytic flux variation in mammal cells.