2,607 research outputs found
Rate of change of circulating 25-hydroxyvitamin D following sublingual and capsular vitamin D preparations
Background: Vitamin D is critical for skeletal health and is increasingly associated with other pathologies encompassing gastrointestinal, immunological, psychological effects. A significant proportion of the population exhibit suboptimal levels of vitamin D, particularly in Northern latitudes in winter. Supplementation is advocated, but few data are available on achievable or typical rates of change. There has been considerable interest in the potential use of sublingual sprays for delivery of nutrient supplements, but data on efficacy remains sparse.
Methods: A randomised, placebo-controlled, 3-arm parallel design study was conducted in healthy volunteers (n=75) to compare the rate of change of vitamin D status in response to vitamin D3 (3000IU/day) supplementation in capsule and sublingual spray preparations over a six-week period between January and April 2017. Blood 25(OH)D concentrations were measured after day 0, 3, 7, 14, 21 and 42 days of supplementation with 3000IU per diem.
Results: Baseline measurements show 25(OH)D deficiency (50mmol/l) in 14.9%, 44.6% and 40.5% of the participants respectively. There was a significant elevation in blood concentrations of 25(OH)D in both of the treatment arms (capsule p=0.003, spray p=0.001) compared to control. The capsule and spray were equally efficacious. The rate of change ranged from 0.69-3.93 (capsule) and 0.64-3.34 (spray) nmol/L day with average change in blood 25(OH)D levels of 2 nmol/l/day. Rates followed a simple normal distribution in the study population (ks= 0.94 and 0.82 for capsule and spray respectively). The data suggest that rates of change are higher in individuals with lower levels of 25(OH)D.
Conclusions: A sublingual vitamin D spray is an effective mode of delivery for supplementation in a healthy population. The data provide reference values and ranges for the rate of change of 25(OH)D for nutrikinetic analyses
Noticing for Equity to Sustain Multilingual Literacies
This department explores how teachers can sustain students’ multilingual literacies and reimagine literacy learning across multiple contexts in conversation with researchers, practitioners, and communities
Reactive Oxygen Species-Mediated Neurodegeneration is Independent of the Ryanodine Receptor in Caenorhabditis elegans
Despite the significant impacts on human health caused by neurodegeneration, our understanding of the degeneration process is incomplete. The nematode Caenorhabditis elegans is emerging as a genetic model organism well suited for identification of conserved cellular mechanisms and molecular pathways of neurodegeneration. Studies in the worm have identified factors that contribute to neurodegeneration, including excitotoxicity and stress due to reactive oxygen species (ROS). Disruption of the gene unc-68, which encodes the ryanodine receptor, abolishes excitotoxic cell death, indicating a role for calcium (Ca2+) signaling in neurodegeneration. We tested the requirement for unc-68 in ROS-mediated neurodegeneration using the genetically encoded photosensitizer KillerRed. Upon illumination of KillerRed expressing animals to produce ROS, we observed similar levels of degeneration in wild-type and unc-68 mutant strains. Our results indicate that ROS-mediated cell death is independent of unc-68 and suggest multiple molecular pathways of neurodegeneration
Two-color resonant four-wave mixing: a tool for double resonance spectroscopy
Two-color resonant four-wave mixing (RFWM) shows great promise in a variety of double-resonance applications in molecular spectroscopy and chemical dynamics. One such application is stimulated emission pumping (SEP), which is a powerful method of characterizing ground-state potential energy surfaces in regions of chemical interest. The authors use time-independent, diagrammatic perturbation theory to identify the resonant terms in the third-order nonlinear susceptibility for each possible scheme by which two-color RFWM can be used for double-resonance spectroscopy. After a spherical tensor analysis they arrive at a signal expression for two-color RFWM that separates the molecular properties from purely laboratory-frame factors. In addition, the spectral response for tuning the DUMP laser in RFWM-SEP is found to be a simple Lorentzian in free-jet experiments. The authors demonstrate the utility of RFWM-SEP and test their theoretical predictions in experiments on jet-cooled transient molecules. In experiments on C{sub 3} they compare the two possible RFWM-SEP processes and show that one is particularly well-suited to the common situation in which the PUMP transition is strong but the DUMP transitions are weak. They obtain RFWM-SEP spectra of the formyl radical, HCO, that probe quasibound vibrational resonances lying above the low threshold for dissociation to H+CO. Varying the polarization of the input beams or PUMP rotational branch produces dramatic effects, in the relative intensities of rotational lines in the RFWM-SEP spectra of HCO; these effects are well-described by their theoretical analysis. Finally, RFWM-SEP spectra of HCO resonances that are homogeneously broadened by dissociation confirm the predicted lineshape and give widths that are in good agreement with those determined via unsaturated fluorescence depletion SEP
Assessment Of Polycyclic Aromatic Hydrocarbons In Locally Smoked Fish Sold In Lagos Markets
Polycyclic aromatic hydrocarbons (PAHs) are known widespread contaminants which represent an important group of carcinogens. This study reports the concentrations of PAHs in smoked fishes locally sold in two markets in Lagos state, Nigeria. The amounts of PAHs present in the samples were quantified using gas chromatography coupled with flame ionization detector (GC-FID). The total concentration of PAHs detected in each sample are 127.5, 86.06, 58.39 and 101.58 μg/kg dry weight for the following fish species respectively; Scomberomorus tritor, Tilapia guinensis, Ilisha africana and Clarias gariepinnus. Benzo[a]pyrene was present in all the samples and the concentration exceeds the permissible limit of 5.0 μg/kg except in one of the fish species. The abundance of high molecular weight PAHs in three of the fish species suggests that pyrolysis was the method used in the smoking process. From the maximum limit set by the European Commission for the sum of PAH, only S. tritor exceeded the 30 μg/kg limit with 54.68 μg/kg present
Suitabilty of Palm Kernel Shell As Coarse Aggregate In Lightweight Concrete Production
Palm kernel shell(PKS) is an agricultural waste which is environmental friendly. This research was focused on the assessment of characteristic strength of palm kernel shell concrete, with the view to be used as lightweight aggregate. This research is carried out to help in reducing construction cost in areas where lightweight concrete canbe considered. Various tests were carried out  in order to ascertain its use as lightweight aggregate. The aim was achieved by casting the beam and cubes with total replacement of granite with PKS and also casting an equivalent control to give a basis for comparison and a water cement ratio of 0.65 at a mix ratio of 1:2:4. A total of 24 beams and cubes each were cast  respectively . They were cured for 7, 14, 21 and 28days. Crushing of 3 each for the Palm Kernel Shell Concrete (PKSC) and Normal Weight Concrete (NWC) for each curing day upto the age of 28 days was carried out. The results of crushing values are as follows for 7, 14, 21 and 28 days; 14.47N/mm2, 18.49N/mm2, 20.33N/mm2 , 23.00N/mm2 and 7.40N/mm2, 9.20N/mm2; 11.30N/mm2 , 13.10 N/mm2, for NWC and PKSC respectively. The value for the flexural strength is as follow; 1.87, 0.91, 1.36, 1.81 and 0.34, 0.34, 0.40, 0.34 for NWC and PKSC respectively. The results showed that the compressive and flexural strength improved with age of curing, though the compressive and flexural strength of PKSC is low as compared to that of the NWC. It was concluded that the compressive and flexural strength of NWC is higher than that of PKSC. Therefore PKSC canbe used as lightweight concrete which should be designed with the corresponding design for NWC. It can therefore be concluded that palm kernel shell is a lightweight aggregate and can be used to produce lightweight concrete. Keywords: Palm kernel shell, lightweight aggregate, compressive strength, flexural strengt
Vitamin D supplementation in people with IBS has no effect on symptom severity and quality of life : results of a randomised controlled trial
Purpose
Several small trials suggest a benefit of vitamin D supplementation in irritable bowel syndrome (IBS). The generalisability of these reports is limited by their design and scale. This study aimed to assess whether vitamin D supplementation improved IBS symptoms in a UK community setting.
Methods
This was a randomised, double-blind, placebo-controlled study. Participants were recruited from the community in winter months between December 2017 and March 2019. 135 participants received either vitamin D (3,000 IU p.d.) or placebo for 12 weeks. The primary outcome measure was change in IBS symptom severity; secondary outcomes included change in IBS-related quality of life.
Results
The participants were analysed on an intent-to-treat basis. 60% of participants were vitamin D deficient or insufficient at baseline. Although vitamin D levels increased in the intervention arm relative to placebo (45.1 ± 32.88 nmol/L vs 3.1 ± 26.15 nmol/L; p < 0.001). There was no difference in the change of IBS symptom severity between the active and placebo trial arms (− 62.5 ± 91.57 vs – 75.2 ± 84.35, p = 0.426) over time. Similarly there was no difference between trial arms in τhe change in quality of life (− 7.7 ± 25.36 vs – 11.31 ± 25.02, p = 0.427).
Conclusions
There is no case for advocating use of vitamin D in the management of IBS symptoms. The prevalence of vitamin D insufficiency suggests routine screening and supplementation should be implemented in this population for general health reasons.
This trial was retrospectively registered with ISRCTN (ISRCTN13277340) on 24th April 2018 after recruiting had been initiated
Integrated stratigraphy of the Kimmeridge Clay Formation (Upper Jurassic) based on exposures and boreholes in south Dorset, UK
For the purposes of a high-resolution multi-disciplinary study of the Upper Jurassic Kimmeridge Clay Formation, two boreholes were drilled at Swanworth Quarry and one at Metherhills, south Dorset, UK. Together, the cores represent the first complete section through the entire formation close to the type section. We present graphic logs that record the stratigraphy of the cores, and outline the complementary geophysical and analytical data sets (gamma ray, magnetic susceptibility, total organic carbon, carbonate, [delta]13Corg). Of particular note are the new borehole data from the lowermost part of the formation which does not crop out in the type area. Detailed logs are available for download from the Kimmeridge Drilling Project web-site at http://kimmeridge.earth.ox.ac.uk/. Of further interest is a mid-eudoxus Zone positive shift in the [delta]13Corg record, a feature that is also registered in Tethyan carbonate successions, suggesting that it is a regional event and may therefore be useful for correlation. The lithostratigraphy of the cores has been precisely correlated with the nearby cliff section, which has also been examined and re-described. Magnetic-susceptibility and spectral gamma-ray measurements were made at a regular spacing through the succession, and facilitate core-to-exposure correlation. The strata of the exposure and core have been subdivided into four main mudrock lithological types: (a) medium-dark–dark-grey marl; (b) medium-dark–dark grey–greenish black shale; (c) dark-grey–olive-black laminated shale; (d) greyish-black–brownish-black mudstone. The sections also contain subordinate amounts of siltstone, limestone and dolostone. Comparison of the type section with the cores reveals slight lithological variation and notable thickness differences between the coeval strata. The proximity of the boreholes and different parts of the type section to the Purbeck–Isle of Wight Disturbance is proposed as a likely control on the thickness changes
Synthetic Mudscapes: Human Interventions in Deltaic Land Building
In order to defend infrastructure, economy, and settlement in Southeast Louisiana, we must construct new land to
mitigate increasing risk. Links between urban environments and economic drivers have constrained the dynamic delta
landscape for generations, now threatening to undermine the ecological fitness of the entire region. Static methods of
measuring, controlling, and valuing land fail in an environment that is constantly in flux; change and indeterminacy are
denied by traditional inhabitation.
Multiple land building practices reintroduce deltaic fluctuation and strategic deposition of fertile material to form the
foundations of a multi-layered defence strategy. Manufactured marshlands reduce exposure to storm surge further
inland. Virtual monitoring and communication networks inform design decisions and land use becomes determined
by its ecological health. Mudscapes at the threshold of land and water place new value on former wastelands. The
social, economic, and ecological evolution of the region are defended by an expanded web of growing land
Development and Evaluation of New Indices for Sediment-associated Contaminants.
New indices (modified hazard quotient, mHQ and ecological contamination index, ECI) are developed for evaluating sediment-associated heavy metals contamination. In evaluating the proposed indices, the concentration and chemical fractionation of five heavy metals (Cd, Cr, Cu, Ni and Pb) determined in benthic sediments from five tropical ecosystems off the Bight of Bonny were used to assess the degree of contamination and estimate the extent of anthropogenic inputs from industrial activities into these ecosystems. The analysis shows that the mean concentrations (mg/kg, dw) of Cd, Cr, Cu, Ni and Pb vary from 4.33 – 5.67, 11.12 – 28.52, 30.26 – 43.72, 2.02 – 2.60 and 162.0 – 190.37, respectively. An important observation is that the mean metal levels during the wet and dry seasons did not show significant variability at all sites. The spatial distribution and severity of sediment-associated contamination by heavy metals based on the developed indices (mHQ and ECI) are in the descending sequence: Cd>Pb>Cu>Cr>Ni. Hence, the observed trend is in good agreement with existing pollution indices. Contamination severity index, mean hazard quotients and modified risk assessment code are also used to identify the pollution hotspots, which reflect medium risk contamination ecological systems. Aquatic pollution indicators (potential contamination index, ECI, hazard quotients, and mHQ) reveal significant anthropogenic contamination of Cd and Pb in the sediments, while Cr, Cu and Ni show relatively low degree of contamination. PCI generally follows the sequence Cd>Pb>Cu>Cr>Ni. Principal component analysis (PCA) and factor analysis indicate that heavy metals in the benthic sediments originate mostly from anthropogenic sources
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