1,052 research outputs found
An Experimental Study on the Mechanical Properties of Low-Aluminum and Rich-Iron-Calcium Fly Ash-Based Geopolymer Concrete
Limited studies have been conducted on low-aluminum and rich-iron-calcium fly ash (LARICFA)-based geopolymer concrete with increased strength. This study aims to investigate the mechanical characteristics of LARICFA-based geopolymer concrete, including its compressive strength, split tensile strength, and ultimate moment. The steps of this study include material preparation and testing, concrete mix design and casting, specimen curing and testing, and the analysis of testing results. Furthermore, the specimen tests consist of the bending, compressive, and split tensile strength tests. The results show that the average compressive strength and the ultimate moment of the geopolymer concrete are 38.20 MPa and 22.90 kN·m, respectively, while the average ratio between the split tensile and compressive strengths is around 0.09. Therefore, the fly ash-based geopolymer concrete can be used in structural components
Estación Intermodal Atocongo - Nueva Centralidad Sur
El argumento del presente estudio de investigación radica en el funcionamiento de la Estación Intermodal de Atocongo - Vía Expresa Sur, teniendo como referencia los últimos proyectos de desarrollo urbanístico de Lima Metropolitana, enlazado con los sistemas de transportes actuales y proyectados, de esta forma generando nuevos equipamientos culturales, comerciales, deportivos, recuperando áreas verdes y de uso público que conecten dos bordes y perforen una gran barrera urbana que divide Lima, creando en conjunto un nuevo centro cívico en la zona sur de la ciudad
Engineered NLS-Chimera Downregulates Expression of Aggregation-Prone Endogenous FUS
Importin β-superfamily nuclear import receptors (NIRs) mitigate mislocalization and aggregation of RNA-binding proteins (RBPs), like FUS and TDP-43, which are implicated in neurodegenerative diseases. NIRs potently disaggregate RBPs by recognizing their nuclear localization signal (NLS). However, disease-causing mutations in NLS compromise NIR binding and activity. Here, we define features that characterize the anti-aggregation activity of NIR and NLS. We find that high binding affinity between NIR and NLS, and optimal NLS location relative to the aggregating domain plays a role in determining NIR disaggregation activity. A designed FUS chimera (FUSIBB), carrying the importin β binding (IBB) domain, is solubilized by importin β in vitro, translocated to the nucleus in cultured cells, and downregulates the expression of endogenous FUS. In this study, we posit that guiding the mutual recognition of NLSs and NIRs will aid the development of therapeutics, illustrated by the highly soluble FUSIBB replacing the aggregation-prone endogenous FUS
17-a-estradiol late in life extends lifespan in aging UM-HET3 male mice; nicotinamide riboside and three other drugs do not affect lifespan in either sex.
In genetically heterogeneous mice produced by the CByB6F1 x C3D2F1 cross, the non-feminizing estrogen, 17-α-estradiol (17aE2), extended median male lifespan by 19% (p \u3c 0.0001, log-rank test) and 11% (p = 0.007) when fed at 14.4 ppm starting at 16 and 20 months, respectively. 90th percentile lifespans were extended 7% (p = 0.004, Wang-Allison test) and 5% (p = 0.17). Body weights were reduced about 20% after starting the 17aE2 diets. Four other interventions were tested in males and females: nicotinamide riboside, candesartan cilexetil, geranylgeranylacetone, and MIF098. Despite some data suggesting that nicotinamide riboside would be effective, neither it nor the other three increased lifespans significantly at the doses tested. The 17aE2 results confirm and extend our original reports, with very similar results when started at 16 months compared with mice started at 10 months of age in a prior study. The consistently large lifespan benefit in males, even when treatment is started late in life, may provide information on sex-specific aspects of aging
The Celiac Disease and Diabetes-Dietary Intervention and Evaluation Trial (CD-DIET) protocol: A randomised controlled study to evaluate treatment of asymptomatic coeliac disease in type 1 diabetes
Introduction: Coeliac disease (CD) is an autoimmune condition characterised by gluten-induced intestinal inflammation, and observed at a 5-10 fold greater prevalence in type 1 diabetes. While universal screening for CD in patients with diabetes is frequently advocated, objective data is limited as to benefits on diabetes control, bone health or quality of life related to the adoption of a gluten-free diet (GFD) in the large proportion of patients with diabetes with asymptomatic CD. The Celiac Disease and Diabetes-Dietary Intervention and Evaluation Trial (CD-DIET) study is a multicenter, randomised controlled trial to evaluate the efficacy and safety of a GFD in patients with type 1 diabetes with asymptomatic CD. Methods and analysis: Children and adults (8-45 years) with type 1 diabetes will be screened for asymptomatic CD. Eligible patients with biopsy-proven CD will be randomly assigned in a 1:1 ratio to treatment with a GFD for 1 year, or continue with a gluten-containing diet. The primary outcome will evaluate the impact of the GFD on change in glycated haemoglobin. Secondary outcomes will evaluate changes in bone mineral density, blood glucose variability and health-related quality of life between GFD-treated and the regular diet group over a 1-year period. The study was initiated in 2012 and has subsequently expanded to multiple paediatric and adult centres in Ontario, Canada. Ethics and dissemination: The findings from this study will provide high-quality evidence as to the impact of GFD treatment on glycaemic control and complications in asymptomatic children and adults with CD and type 1 diabetes. Trial registration number: NCT01566110
Short-course combination treatment for experimental chronic Chagas disease
Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, affects millions of people in the Americas and across the world, leading to considerable morbidity and mortality. Current treatment options, benznidazole (BNZ) and nifurtimox, offer limited efficacy and often lead to adverse side effects because of long treatment durations. Better treatment options are therefore urgently required. Here, we describe a pyrrolopyrimidine series, identified through phenotypic screening, that offers an opportunity to improve on current treatments. In vitro cell-based washout assays demonstrate that compounds in the series are incapable of killing all parasites; however, combining these pyrrolopyrimidines with a subefficacious dose of BNZ can clear all parasites in vitro after 5 days. These findings were replicated in a clinically predictive in vivo model of chronic Chagas disease, where 5 days of treatment with the combination was sufficient to prevent parasite relapse. Comprehensive mechanism of action studies, supported by ligand-structure modeling, show that compounds from this pyrrolopyrimidine series inhibit the Qi active site of T. cruzi cytochrome b, part of the cytochrome bc1 complex of the electron transport chain. Knowledge of the molecular target enabled a cascade of assays to be assembled to evaluate selectivity over the human cytochrome b homolog. As a result, a highly selective and efficacious lead compound was identified. The combination of our lead compound with BNZ rapidly clears T. cruzi parasites, both in vitro and in vivo, and shows great potential to overcome key issues associated with currently available treatments.</p
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