103 research outputs found

    Geotechnical properties of Ajali Sandstone in Enugu, Nigeria for engineering use

    Get PDF
    Twelve soil samples collected at different intervals from 0.1 meter deep in Onyeama Mine, Enugu State from the Ajali sandstone were subjected to geotechnical analysis (moisture content, sieve analysis, Atterberg’s limits) to determine their suitability for the siting of some engineering structures. The results show that the soils are cohesive at shallow depths (1.8m – 1.0m). It is cohesionless with greater sandy fraction at greater depths. The moisture content values are low and averages 10.65% (from depth 0.00m– 1.8m). For the Atterberg limit; liquid limit ranges from 31% - 36% while the plasticity limit was 25%. On the AASHTO classification and plasticity chart, part of these results show that the top soils at shallow depths (1.8m – 1.0m) are inorganic clays. Consequently, the top inorganic layer needs to be stabilized or excavated and back-filled with more stable materials for engineering structures purposes.Keywords: Engineering, Geotechnical Analysis, Geotechnical Properties, Moisture Content, Sandstone, Structure

    Geochemical and sedimentological characteristics of the late quaternary sediments of the Anambra Basin

    Get PDF
    Ten samples from sand bars, mouth bars and continental shelf at the Onitsha end of the River Niger were analyzed for their sedimentlogical and geochemical characteristics. The textural analysis carried out on the samples revealed that they ranged from fine to medium grained, moderately to poorly sorted, angular to sub-rounded. The percentage of sand is high compared to that of silt and clay which has a small percentage. Geochemical analysis shows that the samples are high in silica (SiO2) content, and due to the poorly sorted nature of the sediments, they were described as immature. The mean grain size ranges from 0.8 to 2.9, which corresponds to coarse-fine grain sands but averagely 2.03, which is fine grained. Standard deviation ranges from 0.28 to 1.2, which range from well sorted to poorly sorted but averagely 0.74, which is moderately sorted. The skewness ranges from -0.34 to 1.13 i.e. strongly coarse skewed to strongly fine skewed but averagely near symmetrical. The kurtosis ranges from 0.42 to 1.25 i.e. very platykurtic to leptokurtic but averagely 1.4 which is leptokurtic. The comparison between the samples(sand bar, mouth and continental shelf sediments) revealed certain distinguishing characteristics; the sand bars are better sorted compared to the continental sediments, they are also of fine grain sands, intensive weathering and texturally more mature compared to the continental shelf sediments, whereas the continental shelf is characterized by poor sorting, medium and coarse grains The mouth bar has similar characteristics with the continental shelf with grain size ranging from fine to coarse grained sands.Keywords: Sedimentological, Geochemical, grain size, skewness, kurtosi

    Influence of Selected Soil Properties on Groundwater Flow around Ariaria Dumpsite, Aba, Southeast, Nigeria

    Get PDF
    A study on the analysis of soil and groundwater characteristics due to municipal waste is indispensable to the sustenance of the environment and human health. This study is to evaluate the “Influence of selected Soil properties on groundwater flow around Ariaria dumpsite, Aba Southeast, Nigeria using Particle Size Analysis and Vertical Electrical Sounding (VES) configurationˮ. The sieve analysis shows that the soil samples collected consist of 11.95% of Silt, 83.62% of Sand and 4.42% of little Gravel. The mean permeability of the study area ranges from 0.19 (cm/sec) to 0.49 (cm/sec), the mean infiltration rate ranges from 6840mm/hr to 31320mm/hr. The Longitudinal conductance and Transmissivity values range from 0.0060 to 0.0284Ω-1 and 3.8165 to 16.85892/day. The values of longitudinal conductance and transmissivity indicates that the aquifer has poor protection capacity rating and its classification of well is from very low potential to low potential. The soil samples of the study area are well sorted and the movement of leachate from the dumpsite into the subsurface is very fast because the Permeability (K) is good, Coefficient of uniformity (Cu) and Coefficient of curvature classified the soil samples collected from the area as well graded soil. From the geophysical survey (VES) results, the groundwater depths (upper and lower aquifers) within the study area ranges from 30m (98ft) to 60m (197ft) at average depth of 45m(147ft). The curve types are AHA, HKA and AKA. The SWL of the study area ranges from 12m to 19m deep. The recommend drill depth to groundwater of is 50m (164) for domestic and consumption purpose

    Maternal and perinatal consequences of antepartum haemorrhage of unknown origin

    Get PDF
    Date of Acceptance:22/07/2013 Acknowledgements The authors wish to thank Ms Linda Murdoch and Ms Katie Wilde for extracting the data from AMND.Peer reviewedPreprin

    Longitudinal study to assess changes in arterial stiffness and cardiac output parameters among low-risk pregnant women.

    Get PDF
    AIM: A single-centre, prospective longitudinal study to assess changes in maternal arterial stiffness and cardiac output parameters among low-risk healthy pregnant women. METHODOLOGY: Thirty low-risk, healthy, pregnant women attending their routine antenatal dating ultrasound scan were recruited. Non-invasive assessment of arterial stiffness and cardiac output was undertaken at five gestational windows from 11 to 40 weeks of pregnancy. Data were analysed using a linear mixed model incorporating time and other relevant predictors as fixed effects, and patient as a random effect. RESULTS: Gestational age had a significant effect on all arterial stiffness parameters, including brachial augmentation index (AIx) (p = .001), aortic AIx (p = .002) and aortic pulse wave velocity (p = .002). The aortic AIx (%) reduced during pregnancy: the lowest mean (standard error, SE) was 4.07 (1.01) at 28 weeks before it increased to 7.04 (SE 1.64) at 40 weeks. Similarly, non-invasive assessments of cardiac output (p < .001), stroke volume (p = .014), heart rate (p < .001) and total peripheral resistance (p < .001) demonstrated significant changes with gestational age. Mean cardiac output (l/m) increased during pregnancy reaching a peak at 28 weeks gestation 6.66 (SE 0.28), but dropped thereafter to reach 5.71 (SE 0.25) around term. CONCLUSION: The current study provides pregnancy normograms for gestational changes in arterial stiffness and cardiac output parameters among low-risk, healthy pregnant women. Further work will be required to assess the risk of placental mediated diseases and pregnancy outcome among pregnant women with parameters outside the normal range

    Rheumatoid arthritis and pregnancy: evolution of disease activity and pathophysiological considerations for drug use

    Get PDF
    It has long been known that pregnancy and childbirth have a profound effect on the disease activity of rheumatic diseases. For clinicians, the management of patients with RA wishing to become pregnant involves the challenge of keeping disease activity under control and adequately adapting drug therapy during pregnancy and post-partum. This article aims to summarize the current evidence on the evolution of RA disease activity during and after pregnancy and the use of anti-rheumatic drugs around this period. Of recent interest is the potential use of anti-TNF compounds in the preconception period and during pregnancy. Accumulating experience with anti-TNF therapy in other immune-mediated inflammatory diseases, such as Crohn’s disease, provides useful insights for the use of TNF blockade in pregnant women with RA, or RA patients wishing to become pregnant

    Bone Metabolism in Fetuses of Pregnant Women Exposed to Single and Multiple Courses of Corticosteroids

    No full text
    OBJECTIVE: To estimate the effect of single and recurrent doses of antenatal corticosteroids on fetal bone metabolism. STUDY DESIGN: A secondary analysis of a cohort of pregnant women from a previously reported randomized, placebo-controlled, multi-center trial of women at risk for preterm delivery who received weekly courses of betamethasone (active) or placebo after an initial course of corticosteroids. Umbilical cord serum levels of carboxy terminal pro-peptide of type I pro-collagen (PICP) and cross-linked carboxyterminal telopeptide of type I pro-collagen (ICTP) were measured to assess the rate of fetal bone formation and resorption, respectively. Analysis was stratified according to number of repeat antenatal study courses of betamethasone or placebo (1–3 vs. ≥ 4 courses not including the initial course). RESULTS: Of the 251 umbilical cord serum samples, the median serum ICTP levels, but not PICP levels, were significantly lower with repeat betamethasone exposure compared to placebo (55 vs. 57.9 mcg/L, respectively, p=0.01). In the fetuses exposed to ≥ 4 repeat study courses, there was a significant decrease in median ICTP levels between repeat betamethasone exposure and placebo (53.4 vs. 58.6 mcg/L, respectively, p=0.04) but there was no difference between groups in the fetuses exposed to 1 – 3 repeat study courses (57.4 vs. 56.7 mcg/L, respectively, p= 0.29). CONCLUSION: Levels of umbilical cord serum markers of bone resorption but not formation are reduced in fetuses exposed to repeat courses of antenatal betamethasone. Up to 4 courses of antenatal betamethasone do not appear to affect fetal bone metabolism

    Assessment of some geo-physical, chemical and technical characteristics of soil and groundwater resources in Jesse, south-south Nigeria

    No full text
    This study assessed some geophysical, physicochemical and geotechnical characteristics of soil and groundwater resources in Jesse, Delta State of Nigeria. Earth Resistivity Meter was employed for the electrical imaging of the subsurface. Soil and water samples from the area were taken to the Laboratory for the determination of the physico-chemical, geochemical and geotechnical parameters. The results of the resistivity data shows that a high resistive plume with resistivity &gt;2,000 Ohm-m has penetrated the soil beyond 21m beneath the surface in most parts of the surveyed area. The water samples show mild acidity with pH values in the range 4.3-5.4. Total dissolved solids (TDS) is low 29.35- 33.58mg/L and conductivity ranges from 50.60-60.78 μS/cm. Heavy metal presence is within WHO permissible limit, only Iron is high (0.455-0.889mg/L). Groundwater sample analysis show that total petroleum hydrocarbons-TPH, as oil and grease is below detection level (&lt;0.031mg/L). This can be attributed to the sealing of the confined aquifer by impermeable clay, but fairly high in surface water (≈0.4mg/L). The average permeability of the soil is 8.805 x 10-3cm/s indicating good drainage condition. The results have shown that shallow boreholes are polluted and the soils of the area are acidic. Groundwater of the area needs treatment before it can be consumed and periodic investigations should be carried out in the study area. Keywords: Groundwater, Hydrocarbon, Pollution, Resistivity, Soil

    Antenatal dexamethasone therapy does not affect circulating concentrations of insulin-like growth factor binding protein-1.

    No full text
    In animals, dexamethasone administration during pregnancy leads to fetal growth restriction due to enhanced expression of insulin-like growth factor binding protein-1 (IGFBP-1). In humans, there is also a significant inverse correlation between maternal and fetal concentrations of IGFBP-1 and birth weight. During pregnancy, maternal IGFBP-1 is derived from the decidualized endometrium. We have studied the effect of dexamethasone on circulating concentrations of IGFBP-1 in 12 pregnant women who received dexamethasone therapy for fetal lung maturation in anticipation of premature delivery before 34 completed weeks of gestation. Blood samples were collected before dexamethasone administration, at 24 h and 48 h after the course of dexamethasone, and within 24 h of delivery, for the measurement of IGFBP-1. There was no significant change in plasma IGFBP-1 concentrations at 24 and 48 h following dexamethasone therapy, and at delivery (P = 0.666, 0.307 and 0.398, respectively). Therefore, antenatal dexamethasone therapy does not influence decidual synthesis of IGFBP-1
    corecore