5 research outputs found
Effect of CEC of clay on thermal conductivity
No full textThe thermal conductivity of clay doped with different concentrations of nitrate of heavy
metals is presented in this study. Clay sample from Omi Adio, Ibadan, Southwestern part of Nigeria was used to
investigate this work. Cation exchange, which occurs naturally with soil water, was the method explored to carry out
the investigation. A microprocessor-based thermal analyzer was used to determine the thermal conductivity while
Atomic absorption spectrophotometer was used to determine the heavy metal concentration. 52.0 g clay sample was
mixed with 70 cm3
of nitrate of Pb (II), Cd (II), Zn (II), Cr (II), Fe (II), Hg(II), Cu (II), and Ni (II) solutions at
different concentrationsafter which slabs of dimensions 4cm x 4cm x 1cm were made from the mixture of the clay
sample with aqueous solutions of different concentrations and the thermal conductivities determined. Thermal
conductivity values were plotted against concentration of nitrate of heavy metals400 ppm, 800 ppm, 1600 ppm,
3200 ppm and 6400 ppm. Results showed that thermal conductivity of clay increases with increase in the
concentration of heavy metal adsorbed by the clay to an optimum level. The lowest thermal conductivity was found
to be 0.06W/mK (for control clay) and the highest was found to be 0.38W/mK (at 6400ppm, Copper). For all the
samples, thermal conductivity increases as the concentration of heavy metals increases to a certain optimum level
above which cation exchange is no longer possible. From the results, it was concluded that the increase of
concentration of heavy metals adsorbed by clay during cation exchange process contributes to its thermal
conductivity
Fractional Current Flow in the Subsurface Using Electrical Resistivity Method: A Laboratory Approach
No full textHuman genetic variation with implications for healthcare in Ethiopian populations
No full textCytochrome P450 1A2 metabolizes a wide range of therapeutic drugs, including several used to
treat diseases common in sub-Saharan Africa. Variation in the gene (CYP1A2) has been
reported to be associated with differential efficacy of therapeutic drugs and adverse drug
reactions. To gain a better understanding of the extent of variation in the coding and exonflanking
non-coding regions of CYP1A2, 762 chromosomes from members of five ethnic groups
(Afar, Amhara, Anuak, Maale and Oromo) distributed in a rough north east to south west
transect across Ethiopia were re-sequenced. Substantial variation was observed, much of
which was novel. As a consequence, a diagnostic test based on previously known variation
cannot predict functional variation in Ethiopians. Evidence of purifying selection acting on
CYP1A2 was found and coalescent date estimates of CYP1A2 variants were old, with many
pre-dating expansions of anatomically modern human out of Africa.
Variants within the transcription factor 7-like 2 gene (TCF7L2), which are associated with an
increased risk of type 2 diabetes (T2D), were common in multiple Ethiopian populations.
TCF7L2 haplotype distribution varied among groups suggesting that T2D susceptibility may also
vary, with most groups likely having a West African TCF7L2 risk for the disease and some
having more of a European TCF7L2 risk.
Many CYP1A2 and TCF7L2 haplotypes can be of important predictive value in the planning and
provision of healthcare. These findings are not only of benefit to native Ethiopians, but are also
of increasing importance in the planning of healthcare intervention in the developed world,
where growing numbers of individuals with recent Ethiopian descent are living. Comparing data
with those from publicly available databases it appears that Ethiopian groups display a very high
level of diversity that includes most of the common variation observed elsewhere
Higher dose corticosteroids in patients admitted to hospital with COVID-19 who are hypoxic but not requiring ventilatory support (RECOVERY): a randomised, controlled, open-label, platform trial
No full textBackground
Low-dose corticosteroids have been shown to reduce mortality for patients with COVID-19 requiring oxygen or ventilatory support (non-invasive mechanical ventilation, invasive mechanical ventilation, or extracorporeal membrane oxygenation). We evaluated the use of a higher dose of corticosteroids in this patient group.
Methods
This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing multiple possible treatments in patients hospitalised for COVID-19. Eligible and consenting adult patients with clinical evidence of hypoxia (ie, receiving oxygen or with oxygen saturation <92% on room air) were randomly allocated (1:1) to either usual care with higher dose corticosteroids (dexamethasone 20 mg once daily for 5 days followed by 10 mg dexamethasone once daily for 5 days or until discharge if sooner) or usual standard of care alone (which included dexamethasone 6 mg once daily for 10 days or until discharge if sooner). The primary outcome was 28-day mortality among all randomised participants. On May 11, 2022, the independent data monitoring committee recommended stopping recruitment of patients receiving no oxygen or simple oxygen only due to safety concerns. We report the results for these participants only. Recruitment of patients receiving ventilatory support is ongoing. The RECOVERY trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936).
Findings
Between May 25, 2021, and May 13, 2022, 1272 patients with COVID-19 and hypoxia receiving no oxygen (eight [1%]) or simple oxygen only (1264 [99%]) were randomly allocated to receive usual care plus higher dose corticosteroids (659 patients) versus usual care alone (613 patients, of whom 87% received low-dose corticosteroids during the follow-up period). Of those randomly assigned, 745 (59%) were in Asia, 512 (40%) in the UK, and 15 (1%) in Africa. 248 (19%) had diabetes and 769 (60%) were male. Overall, 123 (19%) of 659 patients allocated to higher dose corticosteroids versus 75 (12%) of 613 patients allocated to usual care died within 28 days (rate ratio 1·59 [95% CI 1·20–2·10]; p=0·0012). There was also an excess of pneumonia reported to be due to non-COVID infection (64 cases [10%] vs 37 cases [6%]; absolute difference 3·7% [95% CI 0·7–6·6]) and an increase in hyperglycaemia requiring increased insulin dose (142 [22%] vs 87 [14%]; absolute difference 7·4% [95% CI 3·2–11·5]).
Interpretation
In patients hospitalised for COVID-19 with clinical hypoxia who required either no oxygen or simple oxygen only, higher dose corticosteroids significantly increased the risk of death compared with usual care, which included low-dose corticosteroids. The RECOVERY trial continues to assess the effects of higher dose corticosteroids in patients hospitalised with COVID-19 who require non-invasive ventilation, invasive mechanical ventilation, or extracorporeal membrane oxygenation
