Preliminary report on magnetic susceptibility measurements on rocks within the Zaria granite batholith, Nigeria

Low field magnetic susceptibility measurements have been carried out within the Zaria granite batholith. The result has shown that magnetic susceptibility within the batholith varies between 29´10 -6 SI to 3506´10 -6 SI, with an average value of 684´10 -6 SI. The large variation in the measured values of the susceptibility is as a result of large variation of magnetic mineral content within an outcrop and the diversity of rock types within individual suite. Thin section observation of representative samples shows the major mineral to be feldspar, quartz and biotite, while magnetite, ilmenite and hematite occur as trace minerals. The frequency distribution shows a bimodal distribution, which is typical of granites due to a low-k peak for paramagnetic dominated specimens and high-k peak for magnetite/hematite dominated specimens. The occurrence of hematite and ilmenite may be due to the alteration of magnetite

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Reduction Of Gravimetric Data Using An Integrated Computer Programme

Gravimetric method of geophysical prospecting requires a methodical combination of both field techniques and data processing. For example drift correction in data processing cannot be successfully carried out without an a priori well-structured observational sequence during field observation that takes cognisance of both the instrumental and diurnal drift effects. The rigour of gravimetric data collection, and the non-availability of comprehensive data reduction software that takes care of local peculiarities, have always constituted hindrance to the application of the gravity method of geophysical studies. However, in recent time, the importance of the gravity method in mineral prospecting and geodynamic studies, has spurred researchers into the use of it. This programme is designed bearing in mind the need to include all the requirements for an all-embracing, up-to-date and exhaustive data reduction scheme. Therefore, the programme begins with systematic conversion of the gravimeter scale readings into an appropriate gravity unit, followed by a comprehensive drift correction routine, which employs the cascade model. The programme has a built-in mechanism, which automatically ties the survey to the international reference standard and computes the theoretical absolute gravity value at every station projected to the reference ellipsoid at the given latitude. In addition, the programme also calculates the observed absolute gravity value at every station, from which the various gravity anomalies are determined. A portion of the programme makes use of altimeter data, if available, to compute the elevation of the gravity station about the mean sea level, and return the result to an output data file. The programme is structured in modular form in order to enhance its flexibility, and with appropriate comment facilities in order to aid its comprehensibility. Keywords: Gravimetric, data, reduction, computer, programme, sequence, modular, cascade, model Nigerian Journal of Physics Vol. 19 (1) 2007: pp. 121-12

Application Of Laplace Interpolation In The Analysis Of Geopotential Data

Geophysical data is often collected at irregular intervals along a profile or over a surface area. But most methods for the treatment of geophysical data often require that any data collected at irregular intervals have to be interpolated to obtain values at regular grid. Unlike the common 2-dimensional interpolation procedures, the Laplace (finite-difference) method can be applied to regions of high data gradients without distortions and smoothing. However, by itself, this method is not convenient for the interpolation of geophysical data, which often consists of regions of widely variable data densities. In this paper a procedure is developed which allows that by combining it with the method of quadratic weighting, the Laplace method can be successfully applied to interpolate two-dimensional geophysical data. These methods were applied to some geopotential data. The results show that there is no significant difference between aeromagnetic maps derived from data as observed and maps obtained when the data is interpolated in a region of thick sedimentary formation. This is attributed to the fact that the magnetic body in such region are deeply buried. However, interpolated aeromagnetic map over a region of outcropping granitic bodies exposes more shallow features which are otherwise not seen on the map derived from the observed data that are not interpolated. Similar observation was recorded for a gravity anomaly map produced from data collected in basement terrain. It was concluded that since it is impossible to observe every point in a given surface area in order to produce an accurate map that will reflect the distribution of the various shallow subsurface anomalies, it is better to interpolate the observed data prior to the production of the desired geopotential map. Keywords: Geophysical, Geopotential, Lapalce interpretation, finite difference, quadratic, weighting. Nigerian Journal of Physics Vol. 19 (1) 2007: pp. 129-13

Geophysics Techniques in the Appraisal of the Integrity of Dumpsite and Groundwater Contamination

This paper attempted to bring to light the hazards associated with the indiscriminate dumping of refuse in towns and cities and the concomitant pollution of groundwater which accounts for over 70% of the domestic use of water. The paper took a critical look at the menace of groundwater contamination resulting from the linkage of leachate from dumpsites and other sources among which are Kaduna, Lokoja, Lagos and China (Carpentel,Ding, and Cheng,2012; Abdullahi,Osazuwa And Sule, 2011; Abdul- Salam, Ibrahim, and Fatoyinbo, 2011; Longe, and Balogun, 2010). The paper recommends among other things that government, its agencies and the general public should employ the services of geophysicists and waste management agencies/experts before establishing a dumpsites/landfills and put in place appropriate monitoring/supervision systems. Finally, the paper concludes by suggesting the use of Geo-electrical survey other than Seismic refraction, magnetic, chemical and microbial as a very convenient method of detecting groundwater contamination without uttering the physical and other properties of the Dumpsites

Preliminarno izvješće o mjerenjima magnetske susceptibilnosti granit-batolit stijena na području Zarie u Nigeriji

Low field magnetic susceptibility measurements have been carried out within the Zaria granite batholith. The result has shown that magnetic susceptibility within the batholith varies between 29 10–6 SI to 3506 10–6 SI, with an average value of 684 10–6 SI. The large variation in the measured values of the susceptibility is as a result of large variation of magnetic mineral content within an outcrop and the diversity of rock types within individual suite. Thin section observation of representative samples shows the major mineral to be feldspar, quartz and biotite, while magnetite, ilmenite and hematite occur as trace minerals. The frequency distribution shows a bimodal distribution, which is typical of granites due to a low-k peak for paramagnetic dominated specimens and high-k peak for magnetite/hematite dominated specimens. The occurrence of hematite and ilmenite may be due to the alteration of magnetite.Mjerenja susceptibilnosti u slabom magnetskom polju provedena su na granit-batolit stijenama u Zariji. Rezultat je pokazao da se magnetska susceptibilnost batolita mijenja između 29 10–6 SI i 3506 10–6 SI, sa srednjom vrijednošću od 684 10–6 SI. Široki interval mjerenih vrijednosti susceptibilnosti posljedica je velike raznolikosti magnetskih minerala unutar izdanka i raznovrsnosti tipova stijena. Proučavanje reprezentativnih uzoraka tankog presjeka pokazuje da su glavni minerali feldspat, biotit i kvarc, dok su magnetit, ilmenit i hematit minerali u tragovima. Raspodjela učestalosti je bimodalna, koja je tipična za granite zbog niskog k-šiljka kod dominirajućih paramagnetskih uzoraka i visokog k-šiljka kod magnetita/hematita. Hematit i ilmenit mogu se pojaviti zbog trošenja magnetita

Contamination of Laboratory Bench-tops, Incubators and the Effects of a Spray-Disinfectant - A Quarterly Ammonium Compound

We surveyed the prevalence of contaminants associated with bench-tops and incubators during a routine working day in our clinical microbiology laboratories in Benin City. A total of 93 swabs, 50 from bench-tops and 43 from inside incubators were randomly collected. One ml of sterile phosphate buffered saline was added into the swab and incubated aerobically at 37oC for 48 hours. Isolated organisms were characterized biochemically. Spray disinfectant, was applied on the bench top and cultured accordingly. Swabs were collected from the incubators every day for 10 consecutive days. Results indicate, that both bench-tops and incubators are contaminated with organisms of clinical importance. Thirty-six (72%) of the swabs yielded growth, with Bacillus subtilis (24%) being the predominant organism, followed by coagulase negative Staphylococcus (CNS) (12%), Staphylococcus aureus (10%), Proteus spp. and Escherichia coli (8%) each, Pseudomonas aeruginosa (4%), moulds (2%) and Candida albicans (2%). Eighteen (41%) swabs from incubators yielded growth, with B. subtilis (13.8%) dominating, followed by Proteus spp. (9.3%), Staphylococcus aureus (6.9%), CNS (4.5%) and moulds (2.2%). Three hours after the spray disinfection, only 5 (10%) of the bench-top swabs yielded growth of B. subtilis, while the swabs from incubators, even after 10 days yielded no growth. This study recommends that spray disinfectant, mostly quaternary ammonium compounds, free of aldehydes can minimize contamination of bench-tops and microbiology incubators during routine working hours. Keywords: Laboratory, contaminants, incubators, bench-tops, spray-disinfectants. Journal of Medical Laboratory Science Vol. 13 (2) 2004: pp. 33-3