4 research outputs found
Modeling of aquifer geo-hydraulic characteristics with geo-electrical methods at a major coastal aquifer system in Uyo, southern Nigeria
Characterization of aquifer geo-hydraulic properties is essential for groundwater management and conservation. This work demonstrates the use of electrical resistivity surveying data in the characterization of important geo-hydraulic properties within a major coastal aquifer in southern Nigeria. Geo-electrical data acquired along profile lines with the use of Schlumberger array configuration were used to determine the aquifer geo-hydraulic parameters such as aquifer resistivity ρb, water resistivity ρw, porosity Φ, formation factor F, hydraulic conductivity K, transmissivity T, permeability Kp, and tortuosity τ. The resistivity inversion models delineated the occurrence of four lithological layers, with resistivity of the geo-layers ranging from 2.4 to 4,393 Ω m. Contour maps were created to show the distribution of the various geo-electrical and geo-hydraulic parameters over the study area. Regression curves showing the relationship between the geo-hydraulic parameters were generated and used to generate empirical relationships between the parameters. The empirical formulas developed for these geo-hydraulic parameters will aid in future work seeking to characterize aquifer zones and model aquifer geo-hydraulic units. In all, electrical resistivity surveying was found to be a noninvasive, cost-effective, and efficient method of characterizing aquifer geo-hydraulic properties via nonpoint geo-electrical data collected over the earth's surface.
HIGHLIGHTS
Vertical electrical soundings were undertaken in the study area.;
The geo-electrical data were used to generate important aquifer geo-hydraulic parameters such as hydraulic conductivity K and transmissivity T.;
The region has locations of low and high resistivity values.;
This major coastal aquifer in southern Nigeria has been characterized.;
Empirical formulas relating the geo-hydraulic parameters have been generated.
Attitude of antenatal attendees to people living with HIV/AIDS in Uyo, south-south Nigeria
Background: Stigmatization and discrimination of people living with
HIV/AIDS has a negative impact on the global efforts to control the
HIV/AIDS pandemic. Due to fear of stigmatization and discrimination,
many people are reluctant to undergo voluntary counseling and testing,
infected individuals are often unwilling to disclose their status and
some of them still engage in high-risk behaviours leading to increased
transmission of the virus. Study design and setting: A study of the
attitudes to people living with HIV/AIDS was carried out among
antenatal clinic attendees at the University of Uyo Teaching Hospital
with the aim of developing site-specific information and counseling
interventions to reduce stigmatization and discrimination of people
living with HIV/AIDS. Information was elicited from 265 randomly
selected women who booked for antenatal care between September and
December 2005 with the use of a self-administered questionnaire.
Results: 263 questionnaires were duly completed and analyzed. The mean
age of the respondents was 27 ± 5.1 years, majority of them
(52.1%) were either unemployed or unskilled workers and 42.9% of them
had tertiary education. Awareness and knowledge of HIV/AIDS was high,
(95.8%) and (86.7%) respectively. Majority of the respondents (55.6%)
were also assessed as having a positive attitude to people living with
HIV/AIDS (PLWHA). There was a statistically significant association
between good knowledge of HIV/AIDS and a positive attitude to PLWHA
(P=0.000) and a high educational status with a positive attitude to
PLWHA (P=0.009). Conclusion: combating stigma and discrimination is an
important process in controlling the epidemic. Specific information and
counseling interventions aimed at dispelling misconceptions about
HIV/AIDS should be reinforced
Factors contributing to uterine rupture in women having vaginal births after caesarean section
Context: Ruptured gravid uterus is a common occurrence in our environment with higher risk in scarred uterus. Some women will attempt vaginal delivery at home after a caesarean section had been performed for cephalopelvic disproportion. Objective: To evaluate the various reasons put forward by our women for attempting vaginal delivery at home despite previous caesarean section. Subjects and Methods: Patients with ruptured gravid uterus during labour with history of previous caesarean section were studied using structured interview formats. Their demographic characteristics, social class, booking status, place of attempted vaginal delivery and various reasons for seeking unorthodox care. Close relative of patients were interviewed in unconscious or moribund patients. Results: Some 24(96.0%) of the patient had no antenatal care in the index pregnancy and had laboured in spiritual churches or in traditional birth attendants homes. Ninteen (76.0%) were of low social class. Various reasons for attempting vaginal delivery at TBA's or spiritual churches included lack of funds 9(37.5%) husbands or close relative not available to take decision for hospital delivery 6(25.0%), not appreciating the need for hospital delivery 3(12.5%) and no reason 1(4.2%). There were 12 maternal deaths giving a case fatality rate of 48%. Conclusion: The study shows socio economic factors, dependency on family decisions and belief in supernatural powers as major reasons our women chose unorthodox delivery despite prior caesarean section and recommend ways of preventing it.Keywords: vaginal birth after caesarean section, uterine rupture Tropical Journal of Obstetrics and Gynaecology Vol. 22(2) 2005: 177-17
Direct Detection of Groundwater Accumulation Zones in Saprock Aquifers in Tectono-Thermal Environments
Some vertical electrical sounding (VES) data from tectono-thermal environments usually plot anomalously on a VES curve, thereby distorting the curve trend at the points of their occurrence. These datasets usually plot noisily in the form of a sudden rise and drop in electrical resistivity values. They constitute abnormal datasets that are usually deleted to recover trends and consequently develop confidence in both the datasets and the modelling and interpretational processes. This study was conducted to assess their origin and consequently gain an understanding of their contributions to groundwater accumulation and transmission in saprock aquifers. The results, supported by co-located drilling and pumping test data, show that these datasets are indicators of subsurface conditions where high-resistivity unconformal structures directly overlie saturated (low-resistivity) porous media, provided that the resistivity of the first breakout point is less than those from subsequent points. Remote sensing data reveal that these types of curves are common in hard rock and metasedimentary environments. Borehole groundwater yields can also be assessed qualitatively from the number and trend of breakoff points. The integrity of the breakoff points must be affirmed by using more sensitive equipment for data acquisition and repeating the measuring process using different potential electrode separations and—where possible—VES profile orientation