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Drilling cost optimization for extended reach deep wells using artificial neural networks
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Urinary schistosomiasis among vulnerable children in a rehabilitation home in Ibadan, Oyo state, Nigeria
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Page will reload when a filter is selected or excluded.- Heterogeneous reservoir 2 results 2
- In recent years, mortality due to leptospirosis in dogs has been of major concern in Southwestern Nigeria, but the prevalent serovars, pathology and pathogenesis have not been fully documented. The purpose of this study was to investigate the disease in the dog and reservoir hosts (cattle and wild rats), and its pathogenesis and pathology in a guinea pig model. Between 2003 and 2010, 44 fresh and 60 formalin-fixed kidneys of tentatively diagnosed cases of canine leptospirosis obtained at necropsy from the two Veterinary Teaching Hospitals in Southwestern Nigeria, fresh kidneys of 108 asymptomatic cattle and 105 wild rats obtained from abattoirs were investigated histopathologically and for the presence of leptospiral organisms using Ellinghausen-McCullough-Johnson–Harris (EMJH) medium, microscopic agglutination test with monoclonal antibodies (MAT-Ab), polymerase chain reaction (PCR), Warthin Starry silver stain (WSss), and immunohistochemistry (IH). The chronicity of the canine infection was determined by renal histopathology. Forty guinea pigs were experimentally infected with 107 Leptospira interrogans serovar icterohaemorrhagiae, while 20 served as controls. The clinico-pathological changes, pathogenesis and pathology were investigated by sacrificing at 12, 24, 72, 96, 120 and 168 hrs post infection (p.i.). Data was analysed using descriptive statistics. Interstitial nephritis and tubular nephrosis were the most common renal lesions in dogs (88.4% and 76.7%), cattle (77.8% and 74.1%) and wild rats (62.9% and 67.6%), respectively. Leptospires were isolated from 84.1% dogs, 82.4% cattle and 68.9% wild rats. Serovars identified in dogs, cattle and wild rats were icterohaemorrhagiae (29.7%, 9.7%, 33.0%), pomona (18.5%, 3.2%, 23.8%), bratislava (11.1%, 22.6%, 4.8%), hardjo (0%, 29.0%, 0%), canicola (14.8%, 6.5%, 14.3%) and grippotyphosa (14.8%, 9.7%, 14.3%); unidentified isolates were 11.1%, 19.4%, 9.5% respectively. The virulence gene (285bp) was confirmed in 31.3% of canine, 81.8% of wild rat and 61.9% of bovine kidneys. The IH and WSss showed that in acute canine infections, leptospires were present in different renal tissues, but were only found attached to tubular epithelium in the more chronic infections. The guinea pig infection was characterized by anorexia, dullness, slight icterus, normocytic normochromic anemia, and thrombocytopenia. The detection of leptospires in different organs was time-dependent, but persisted only in the kidney after 120 hrs p.i. In the pancreas, the organism could only be detected by cultural isolation and PCR (12-72 hrs p.i.). Renal tubular necrosis and interstitial nephritis, hepatic necrosis and cord dissociation, pulmonary haemorrhages, acute pancreatitis, adrenal vacuolar degeneration, non-suppurative myocarditis and encephalitis were observed. Immunohistochemistry showed leptospiral antigens in the brain from 12-24 hrs p.i. Icterohaemorrhagiae and pomona were the two most frequently isolated serovars from canine leptospirosis in Southwestern Nigeria. Structural localisation of the organism within the kidney may be an indication of the stage of infection. Renal lesions of leptospirosis were present in asymptomatic reservoir hosts. In addition to the well documented renal, hepatic, and pulmonary pathology, lesions of leptospirosis were also found in several other organs. 2 results 2
- Modelling 2 results 2
- Oil recovery 2 results 2
- Permeability anisotropy 2 results 2
- Reservoir hosts 2 results 2
- Reservoir performance 2 results 2
- Understanding the basic mechanisms that govern flow of hydrocarbon in any given reservoir situation is necessary in developing reliable methods of predicting behaviour in that reservoir. Most reservoirs in Agbada Formation of the Niger Delta Basin are anisotropic and therefore heterogeneous, which is a vital parameter in the efficient production of hydrocarbons. This work looked at the effect of permeability anisotropy (Kv/Kh) or heterogeneous distribution and its effects on reservoir performance using windows based IPM-MBAL petroleum engineering software. Results analysis revealed that anisotropy makes reservoir production modelling more realistic than the isotropic scenarios, and degree of heterogeneity improves oil recovery from the reservoir (Kv/Kh = 1, R.F = 49.31%; Kv/Kh = 0.1, R.F = 49.95%; Kv/Kh = 0.001, R.F = 50.60%; Kv/Kh = 0.0001, R.F = 51.24%). Reservoir heterogeneity should be included in reservoir modelling practices because it has a significant effect on hydrocarbon production. 2 results 2
- Agricultural land-use 1 results 1
- Alpha-glucooxidase 1 results 1
- AmpC 1 results 1
- An empirical equation that could be used for predicting the viscosity of Nigerian crudes is presented in this paper. The correlation uses oil specific gravity as the main correlating parameter, and also incorporates the effects of reservoir pressure, temperature and oil formation volume factor. Data from well over 400 samples of Nigerian crudes were used for developing the correlation, with most samples however, from reservoirs at or above saturation pressure. The results show however that the correlation could have general applicability. The correlation when compared with some earlier works proved to be more accurate for Nigerian crudes. Graphical and Statistical error analyses undertaken suggest good performance and accuracy. The correlation should prove valid for estimating the viscosity of Nigerian crudes, as well as other crude types having properties that fall within the range of the data used in this work. 1 results 1
- Antibiotics 1 results 1
- Antimicrobial 1 results 1
- Artificial Neural Networks 1 results 1
- Background: Cockroaches are carriers of numerous microorganisms. However, there is paucity of information on their role as potential reservoir for beta-lactamase producers. Objectives: This research determined the antibiotics susceptibility profile of Beta-lactamase producing Gramnegative bacteria isolated from the gut of household cockroaches in selected locations in and around University of Ibadan, Oyo state. Materials and Methods: Thirty Cockroaches from different locations in and around University of Ibadan were collected between June 2015 and March, 2016, and their intestinal homogenates cultured on different selective media for the isolation of bacteria. The isolates were identified using a combination of biochemical tests and 16S rRNA sequencing. Antibiotic susceptibility testing was done using the disc-diffusion technique and phenotypic detection of extended-spectrum beta-lactamase (ESBL), AmpC-beta-lactamase (AmpC) and Metallo-beta-lactamase (MBL) production was done using double-disc synergy, cefoxitin/cloxacillin and imipenem/EDTA double-disc methods respectively. Results: A total number of 58 bacteria belonging to nine genera; Pseudomonas, Proteus, Klebsiella, Salmonella, Enterobacter, Escherichia, Serratia, Shigella and Raoultella were isolated. Higher percentage of the isolates exhibited resistance to erythromycin (90%), azithromycin (87.5%), amoxicillin (84.5%), ampicillin (74.1%), amoxicillin-clavulanic acid (74.1%), cefoxitin (67.2%) and chloramphenicol (54%), while lower percentage showed resistance to aztreonam (25%), ertapenem (13%), cefotaxime (8.6%), ceftazidime (10.3%), cefepime (5.2%), ciprofloxacin (3.5%), gentamicin (5.2%) and imipenem (0%). MDR phenotype was recorded among 82% of the isolates, 17.2% were positive for ESBL, 12% for AmpC and 13.8% for MBL production. Conclusion: This study identified household cockroaches Periplaneta americana, as a potential reservoir for MDR and beta-lactamase-producing isolates. Keywords: Susceptibility testing, ESBL, AmpC, MBL, Beta-Lactamase, MDR, Household cockroaches Cockroaches are insects of the order Blattodea some of which are associated with human environment (Beccaloni, 2014). One of the two species of cockroaches that has been reported by different authors to be widely distributed in Nigeria is the American cockroaches namely Periplaneta americana (Ajero et al., 2011; Etim et al., 2012; Akinjogunla et al., 2012; Tilahun et al., 2012). The incidence of Cockroach infestation in restaurants, hospitals, warehouses, offices and within households, particularly the kitchen, have been reported to be very high in Nigeria (Omudu and Akosu, 2013; Braimah et al., 2015). The insects being nocturnal in nature are found in dark places within the households during the day hiding in opened and cracked sections of the wall, furniture, inside wardrobes and cupboards (Omudu and Akosu, 2013; Billah et al., 2015; Braimah et al., 2015). Sometimes they enter into cooking pots and other kitchen utensils if left opened. They feed on leftover food, cooked and uncooked food materials contaminating them with microorganisms on their body and in their faecal droppings especially those ready to eat food that do not require further processing before eating them (Xue et al., 2009). They are also found in other parts of the house including bedrooms (Etim et al., 2013). Cockroaches are also found in garbage and sewage tanks, particularly in homes with pit latrine (Craczyk et al., 2005; Pai et al., 2005) making them a potential vector for pathogenic and non-pathogenic microorganisms from human origin (Graczyk et al., 2005; Pai et al., 2005; Vazirianzadeh et al. 2014). Studies have shown that most of the disease-causing bacteria of human origin can survive within the body system of cockroaches (Imamura et al., 2003), hence their presence in sewage and garbage elucidate their role as potential carriers of these human diseasecausing agents (Vazirianzadeh et al., 2014). Several authors have incriminated cockroaches as reservoir and transmitters of disease-causing microorganisms like Enterobacter spp., Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella spp., Campylobacter spp. and Salmonella spp., especially those in the hospital environment (Craczyk et al., 2005; Tatfeng et al., 2005; Ukay et al., 2009; Tilahun et al., 2012; Vazirianzadeh et al., 2014). In addition, cockroaches have also been reported to carry microbial agents of leprosy, urinary tract infection (Enterococcus spp.), MATERIALS AND METHODS Study Area The study was carried out in University of Ibadan metropolis, Oyo state. The areas of choice were kitchen and toilets in residential apartments in and around the University of Ibadan. Specimen Collection and Preparation for bacteria isolation A total of 30 cockroaches, identified to be Periplaneta americana, through online file (Beccaloni, 2014), were collected from residential cholecystitis (Helicobacter hepaticus), plague (Yersinia pestis) and bacteremia, septic arthritis and peritonitis (Oligella urethralis) (Pat, 2006; Falsafi and Mahboubi, 2013). Antibiotic resistance and its spread among bacterial isolates is a global problem and has been reported among bacterial isolates in both clinical and community settings (WHO, 2014). Cockroaches have been reported to harbour pathogenic and opportunistic pathogens that exhibited high level resistance to antibiotics, especially those used in lifethreatening disease cases such as the cephalosporins and carbapenems (Fathpour et al., 2003; Bouamama et al., 2010; Wannigama et al., 2014). Bacterial isolates exhibiting multidrug resistance phenotype have also been reported in cockroaches (Devi and Murray, 1991; Tetteh-Quarcoo et al., 2013). Resistance to beta-lactam antibiotics are known to be mediated mostly by beta-lactamase enzymes. The initial variants of these enzymes were active only on the penicillin class but the discovery of the third generation cephalosporin class help to overcome their destructive action (Paterson and Bonomo, 2005). The advent of extended-spectrum beta-lactamase, and metallo beta-lactamase enzymes among others which are known in addition to the penicillin class, to hydrolyze the third generation cephalosporins (Ceftazidime, cefotaxime, ceftriaxone) and the carbapenems (imipenem, ertapenem) respectively, created a serious problem for clinicians in the management of life-threatening infections caused by such bacteria habouring the enzymes (Paterson and Bonomo, 2005). Currently, there is paucity of information on the various resistant determinants harboured by bacteria isolated from household cockroaches. This study therefore, aimed at using phenotypic techniques to determine multidrug resistance phenotype and the presence of common beta-lactamase enzymes among bacterial isolates from the gut of house-hold cockroaches in selected locations in and around University of Ibadan. apartments using sticky rods and direct collection with sterile hand-gloves (Paul et al., 1992). They were introduced into separate sterile wide-mouth bottles aseptically and transported to the laboratory of the Department of Pharmaceutical Microbiology, University of Ibadan for freezing at 0oC for 10- 15min to anaesthetize them. Intestinal gut of each cockroach was prepared into samples using the method highlighted by Tetteh-Quarcoo et al. (2013) 1 results 1
- Background: Schistosomiasis is a disease of public health importance with long term complications mostly common among children, rural dwellers, poor and migrant workers. Studies have not documented the burden among migrant workers and their families. The study aimed to describe the burden of schistosomiasis and demographic characteristics among children of migrant workers residing in a rehabilitation home in Ibadan, Nigeria. Methods: A cross-sectional study using sixty six children, who were tested following complaints of haematuria by six of them. An interviewer-administered questionnaire was used to collect information on demographic and environmental characteristics of the children and urine microscopy, was conducted. Data was analysed using descriptive statistics and correlation. Statistical significance was set at 5%. Results: Mean age of respondents was 11.8 ± 4.0 years and 57.6% were males. The prevalence of schistosomiasis was 19.7% with preponderance among males (64.3%) and children aged 12 years and above (71.4%); 85.7% of infected children were from Kwara State; 78.6% waded in water body and 92.9% had red blood cells and pus cells on urine microscopy. Conclusions: The burden of schistosomiasis is high among children of migrant workers and they serve as reservoirs for transmission of the disease. Government needs to work synergistically with NGOs, FBOs and other partners to achieve schistosomiasis prevention and control among this particular group. 1 results 1
- Begs and brill traverse 1 results 1
- Beta-Lactamase 1 results 1
- Bottom-hole pressures in gas and condensate wells are frequently measured at a great cost and with operational challenges. On the other hand, most analytical estimation procedures either use trial and error or neglect liquid holdup in condensate wells. Using the mechanical energy balance approach, an approximate model was developed to estimate bottom-hole pressure from wellhead pressures in condensate wells without neglecting liquid holdup. The results show that treating gas condensate like dry gas wells lead to over prediction (10-15%) of flowing bottom-hole pressures, with serious consequences on phase behaviour, reservoir characterization and production management. 1 results 1
- Calves 1 results 1
- Child health 1 results 1
- Containment 1 results 1
- Crop farming 1 results 1
- Dandaru reservoir 1 results 1
- Desilting 1 results 1
- Diarrhoea in young pre-weaned calves is one of the most important causes of calf morbidity and mortality. Information on this multi-aetiological condition is scanty in Nigeria. Therefore, we studied the prevalent bacteria and antibacteria susceptibility to various bacterial isolates from faecal samples of suspected cases of calf scours in Oyo and Ogun States of South-western Nigeria. One hundred and twenty calf faecal samples (120) from various breeds of cattle showing clinical manifestation of scours were screened for bacterial agents in two farms in Oyo and five farms in Ogun States. Isolation and identification were done using standard procedures, while antibiotic sensitivity was done using Kirby Bauer's disc diffusion method. Escherichia coli, Salmonella spp. and Campylobacter spp. were identified. Out of all the calves, 19 calves (15.8%) were positive for bacteria agents, E. coli was isolated from 12 calves (10%), Salmonella spp. was isolated in 10 calves (8.3%) and Campylobacter spp. was isolated in 1 calf (0.8%). Antibiotic sensitivity test revealed that the most sensitive antibiotics were Meropenem (91.3%) and Amikacin (82.6%) while the least sensitive was Ampicillin (21.7%). Therefore Meropenem is the most sensitive antibiotic and recorded the highest percentage sensitivity in all the three bacteria pathogens isolated, while Ampicillin appeared to be the least sensitive antibiotic to virtually all the pathogens isolated. Meropenem is therefore recommended as the drug of choice for the management of bacteria calf scours. The isolation of highly pathogenic E.coli 0157 from calf scour cases reaffirmed cattle as a reservoirs host which may enter the food chain and poses a faeco-oral potential public health hazards. 1 results 1
- ESBL 1 results 1
- Endemicity 1 results 1
- Eutrophication 1 results 1
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