38 research outputs found

    Integrating Resistivity Techniques for Optimum Groundwater Exploration and Development within a Hotel Facility in Osogbo, Southwestern Nigeria

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    This work is an attempt to combine dipole-dipole profiling and vertical electrical sounding techniques of electrical resistivity methods to investigate the groundwater potential within the premises of a 3-star hotel facility in Osogbo, Nigeria by delineating the geoelectric layers, delineating the low resistivity layers, determining the lithologies and hence, delineating the groundwater bearing zones. The five vertical electrical sounding data were collected along two pre-surveyed dipole-dipole traverses at right angle to each other beside the fences of the premises using the ABEM SAS 300c terrameter. The observed data were interpreted quantitatively using curve matching and computer-assisted iteration method using the WinResist and Dipro software. The results of the inversion show that the lithology comprises of the top soil and an intermittent sequence of sand and lateritic clay having varying resistivity and thickness. The aquiferous layer was observed to be located at a depth of 23 m to 25 m due to the low resistivity and high thickness of the aquiferous layer. The result of the 2-D imaging closely correlates with the result of the vertical electrical sounding. Thus, combining these techniques in groundwater investigation has achieved similar result as the Werner technique and has reduced ambiguity and error in positioning for drilling. Keywords: Resistivity, Groundwater Exploration, Dipole-Dipol

    Integrating Resistivity Techniques for Optimum Groundwater Exploration and Development within a Hotel Facility in Osogbo, Southwestern Nigeria

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    This work is an attempt to combine dipole-dipole profiling and vertical electrical sounding techniques of electrical resistivity methods to investigate the groundwater potential within the premises of a 3-star hotel facility in Osogbo, Nigeria by delineating the geoelectric layers, delineating the low resistivity layers, determining the lithologies and hence, delineating the groundwater bearing zones. The five vertical electrical sounding data were collected along two pre-surveyed dipole-dipole traverses at right angle to each other beside the fences of the premises using the ABEM SAS 300c terrameter. The observed data were interpreted quantitatively using curve matching and computer-assisted iteration method using the WinResist and Dipro software. The results of the inversion show that the lithology comprises of the top soil and an intermittent sequence of sand and lateritic clay having varying resistivity and thickness. The aquiferous layer was observed to be located at a depth of 23 m to 25 m due to the low resistivity and high thickness of the aquiferous layer. The result of the 2-D imaging closely correlates with the result of the vertical electrical sounding. Thus, combining these techniques in groundwater investigation has achieved similar result as the Werner technique and has reduced ambiguity and error in positioning for drilling

    Recommendation of RILEM TC 261-CCF: test method to determine the flexural creep of fibre reinforced concrete in the cracked state

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    [EN] To date there is no clear consensus about how creep of cracked FRC structural elements should be considered. In recent years, different methodologies have been developed for multiple stress cases. The absence of a standardised methodology to evaluate flexural creep in the cracked state has hindered general comparisons and conclusions that could lead to significant advances in this topic. Since 2014, the study of the creep behaviour of cracked FRC has been coordinated by the RILEM TC 261-CCF. All the available creep methodologies were analysed in terms of procedure, equipment and results. A comprehensive Round-Robin Test (RRT) on the creep behaviour of cracked sections of FRC was proposed and undertaken by a total of 19 participant laboratories from 14 countries all over the world. The analysis and conclusions of the RRT results and the different methodologies provided the basis for this recommendation. This recommendation focuses on the test method to evaluate the flexural creep of FRC specimens in the cracked state. Guidelines on specimen production, detailed test equipment, experimental setup and test procedure as well as the definitions of the most relevant parameters are provided.Llano-Torre, A.; Serna Ros, P. (2021). Recommendation of RILEM TC 261-CCF: test method to determine the flexural creep of fibre reinforced concrete in the cracked state. Materials and Structures. 54(3):1-20. https://doi.org/10.1617/s11527-021-01675-0S120543Theodorakopoulos D (1995) Creep characteristics of glass reinforced cement under flexural loading. Cement Concr Compos 17:267–279Chanvillard G, Roque O (1999) Behaviour of fibre reinforced concrete cracked section under sustained load. High Performance Fiber Reinforced Cement Composites (HPFRCC 3) Mainz, Germany, pp 239–250, RILEM PRO 06Kurt S, Balaguru P (2000) Post crack creep of polymeric fibre-reinforced concrete in flexure. Cem Concr Res 30(2):183–190Mackay J, Trottier JF (2004) Post-crack behavior of steel and synthetic FRC under flexural creep. In: Shotcrete, Proc. 2nd Intnl. Conf. on Engineering, Cairns, Australia (2004), pp 183–192Kusterle W (2009) Viscous material behaviour of solids- creep of polymer fibre reinforced concrete. In: Proc. 5th Central European Congress on Concrete Engineering. obv, Baden, pp 95–100Arango S, Serna P, Martí-Vargas JR, García-Taengua E (2012) A test method to characterize flexural creep behaviour of pre-cracked FRC specimens. Exp Mech 52(8):1067–1078Zerbino RL, Barragan BE (2012) Long-term behaviour of cracked steel fibre-reinforced concrete beams under sustained loading. ACI Mater J 109(2):215–224Abrishambaf A, Barros JAO, Cunha VMCF (2015) Time-dependent flexural behaviour of cracked steel fibre reinforced self-compacting concrete panels. Cem Concr Res 72:21–36Buratti N, Mazzotti C (2016) Experimental tests on the long-term behaviour of SFRC and MSFRC in bending and direct tension. In: Proceedings of the BEFIB 2016, 9th RILEM international symposium on fiber reinforced concrete, pp. 163–174, Vancouver, Canada, 19–21 Sept 2016Babafemi AJ, Boshoff WP (2015) Tensile creep of macro-synthetic fibre reinforced concrete (MSFRC) under uni-axial tensile loading. Cement Concr Compos 55:62–69Vrijdaghs R, di Prisco M, Vandewalle L (2018) Uniaxial tensile creep of a cracked polypropylene fiber reinforced concrete. Mater Struct 51:5. https://doi.org/10.1617/s11527-017-1132-5Vasanelli E, Micelli F, Aiello MA, Plizzari G (2013) Long term behaviour of FRC flexural beams under sustained load. Eng Struct 56:1858–1867Bernard ES (2010) Influence of fibre type on creep deformation of cracked fibre-reinforced shotcrete panels. ACI Mater J 107(5):474–480EFNARC (2012) Testing sprayed concrete—Creep test on square panelLarive C, Rogat D, Chamoley D, Regnard A, Pannetier T, Thuaud C (2016) Influence of fibres on the creep behaviour of reinforced sprayed concrete. In: Proceedings of ITA World Tunnel Congress WTC 2016, April 22‐28, San Francisco, United StatesMonetti DH, Llano-Torre A, Torrijos MC, Giaccio G, Zerbino R, Martí-Vargas JR, Serna P (2019) Long-term behavior of cracked fiber reinforced concrete under service conditions. Construct Build Mater; 196:649–658. https://doi.org/10.1016/j.conbuildmat.2018.10.230Llano-Torre A., Martí-Vargas JR, Serna P (2020) Flexural and compressive creep behavior of UHPFRC specimens. Construct Build Mater; 244:118254. https://doi.org/10.1016/j.conbuildmat.2020.118254Serna P, Llano-Torre A and Cavalaro S H P (ed) (2017) Creep behaviour in cracked sections of fibre reinforced concrete: proceedings of the international RILEM Workshop FRC-CREEP 2016. RILEM bookseries 14 (Dordrecht: Springer)Llano-Torre A, Serna P, Cavalaro SHP (2016) International round robin test on creep behavior of FRC supported by the RILEM TC 261-CCF. In: Proceedings of the BEFIB 2016, 9th RILEM international symposium on fiber reinforced concrete, pp 127–140, Vancouver, Canada, 19–21 Sept 2016Serna P, Llano-Torre A, García-Taengua E, Martí-Vargas JR (2015) Database on the long-term behaviour of FRC: a useful tool to achieve overall conclusions. In: Proceedings of the 10th international conference on mechanics and physics of Creep, Shrinkage, and Durability of Concrete and Concrete Structures, Vienna, September 2015, pp 1544–1553Llano-Torre A., Serna P. (eds) Round-Robin test on creep behaviour in cracked sections of FRC: experimental program, results and database analysis. RILEM State-of-the-Art Reports. Springer. https://doi.org/10.1007/978-3-030-72736-9ASTM International (2015) C1812/C1812M-15e1 Standard Practice for Design of Journal Bearing Supports to be Used in Fiber Reinforced Concrete Beam Tests. West Conshohocken, PA; ASTM International. https://doi.org/10.1520/C1812_C1812M-15E0

    Mycobacterium Chelonae Line Sepsis in a 4-Year-Old Male with Acute Myeloid Leukaemia (AML)

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    Background: Mycobacterium chelonae (MC) was isolated from an immunosuppressed four-year-old with Acute Myeloid Leukaemia. This was initially dismissed as gram positive bacil li diptheroid based on gram staining. Several more blood culture bottles flagged up positive in quick succession. A review of the gram stain with additional ZN staining revealed acid-fast bacilli and finally identified as Mycobacterium chelonae. Case Presentation: a 4-year-old (now 5) male with acute myeloid leukaemia presented to Emergency department at Sou thend hospital with febrile non-neutropenia/low grade fever, loss of appetite, weight loss and general weakness. Suspected Sore and infected gastrostomy site, with percutaneous endoscopic gas trostomy (PEG). Blood cultures were collected and patient put-on broad-spectrum antibiotics and antifungal. 5 sets yielded Myco bacterium chelonae. The patient was kept on broad spectrum anti biotics with additional meropenem, removal of PEG and follow up blood cultures were negative. Conclusion: Nontuberculous mycobacteria, particularly fast growers, should be considered or excluded by ZN staining in pos itive cultures after 2-4 days from immunosuppressed patients with gram positive rods (GPRs) on gram staining, thisis even more necessary if patients have lines insitu. Several multiple sets of blood culture will also be helpful to rule out contamination. Laboratories should attempt to identify NTM by Matrix Assisted Laser Desorp tion-Time of Flight (MALDI-TOF) by full extraction if available. If the isolate is considered clinically significant, a full antibiotic susceptibility should be sought to guide therapy

    Development: Unconventional Monetary Policy on Bank Performance in Nigeria

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    The banking system plays an important role in the Environment and Development. This literature explored the influence of unconventional monetary rule on bank financial efficiency, with a vision to analysis to what degree unorthodox monetary expansion would impact deposit money banks’ performance using Nigeria as a case study for the developing economies in Africa from (2007-2017). Unorthodox monetary expansion is evaluated via assets of the apex bank to GDP ratio and deposit insured during the period. Using the random effect regression panel data analysis, the findings indicate that unconventional monetary policy is of a negative effect on deposit money bank performance. Further analyses show a negatively expressive relation amid unconventional pecuniary rule and Credit Money Banks performance with regards to deposit insurance coverage. On this basis, this literature principally recommends the apex bank of Nigeria to enact monitory regulations aiming to examine the response of credit finance banks’ performance to unconventional measures of monetary policy. The Unconventional Monetary Policy plays an important role in Development

    Seroprevalence of Toxoplasma gondii and Associated Risk factors Among Pregnant Women Attending Antenatal Care in Ilala Municipality, Dar es Salaam, Tanzania

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    ABSTRACT Background: Toxoplasma gondii (T. gondii) infection during pregnancy is associated with various complications for the mother and baby. In Tanzania, there is a paucity of data on exposure to T. gondii infection among pregnant women and the associated risk factors. Therefore, this study investigated the seroprevalence of T. gondii and associated factors among pregnant women attending antenatal care in Ilala Municipality, Dar es Salaam. Methods: A cross sectional study was carried out among 383 pregnant women attending antenatal health care. A five mL of blood sample was collected from each recruited pregnant woman, processed to obtain serum, and tested for the presence of IgG and IgM anti T. gondii specific antibodies. A structured questionnaire was used to gather information on the risk factors predisposing pregnant women to the infection. Data analysis was performed using descriptive statistics and logistic regression. Results: Of the 383 participants, 104 (27.2%) were positive for antibodies specific to T. gondii; 102 (26.63%) were positive only for IgG, and 2 (0.52%) were positive for both IgM and IgG antibodies. Significant risk factors for T. gondii infection were maternal age of 34-39 years (AOR:3.71;95% CI:1.52-9.06), eating unwashed fruits (AOR:7.39;95% CI:3.99-13.66), not washing hand with soap after meat preparation (AOR:7.53; 95% CI:3.40-16.64), consumption of undercooked meat (AOR:3.75; 95% CI:1.95-7.21), and consumption of raw vegetable (AOR: 1.99; 95% CI: 1.04-3.80). Cat ownership was not statistically significantly associated with toxoplasmosis (AOR:1.90; 95% CI: 0.89-4.08). Conclusions: The seroprevalence of T. gondii infection (27.2%) indicates ongoing transmission, hence the need for regular screening during antenatal care and establishment of a control programme

    Vitamin D3 Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor-Cognitive Function in −D2R Parkinsonian Mice Model

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    Background: fourth generation antipsychotics have been implicated in the blockade of calcium signalling through inhibition of dopamine receptive sites on dopaminergic D2 Receptor (D2R). As a result of the abnormal calcium signalling associated with D2R inhibition, changes occur in the motor and memory neural axis leading to the observed behavioural deficits after prolonged haloperidol. Thus, Vitamin D3 receptor (VD3R), a calcium controlling receptor in the striatum can be targeted to relief the neurological symptoms associated with haloperidol (−D2R) induced PD. Aim: This study sets to investigate the role of VD3R activation in vitro and in vivo after haloperidolinduced Dopaminergic (D2R) blockade. In addition, we examined the associated neural activity and behavioural changes in parkinsonian and VDRA intervention mice. Methods: Dopaminergic D2R inhibition was investigated in vitro using Melanocytes isolated from the scale of a Tilapia. In four separate set ups, the cells were cultured in calcium free Ringer’s solution as follows; 300 ÎŒM haloperidol, 100 ÎŒM VD3, 100 mM calcium chloride and a combination of 300 ÎŒM haloperidol and 100 ÎŒM VD3. Subsequently, dopaminergic vesicle accumulation and calcium signalling were observed in bright field microscopy using blue and green fluorescence probes. In the second phase, PD was induced in adult BALB/c mice (−D2; n = 8) after 14 days of intraperitoneal haloperidol treatment (10 mg/Kg). A set of n = 4 mice were untreated (−D2) while the other group (n = 4) received 100 mg/Kg of VD3 for 7 days (−D2/+VDR). The control groups (n = 4 each) were treated with normal saline (NS) and VD3 (+VDR) for 14 days. At the end of the treatment phase, the animals were assessed in Rotarod, parallel bar-, cylinder-, Y-Maze-, one trial place recognition- and novel object recognition-(NOR) tests. Neural activity was measured using chronic electrode implants placed in the M1 (motor cortex), CPu (striatum), CA1 (hippocampus) and PFC (prefrontal cortex). Neural activity was compared with the outcomes of behavioural tests for memory and motor functions and data was expressed as mean ± SEM (analysed using ANOVA with Tukey post-hoc test, significant level was set at 0.05). Results/Discussion: in vitro outcomes show that VDR increase calcium signalling and reverses the effect of haloperidol; specifically by reducing dopaminergic vesicle accumulation in the cell body. Similarly, in vivo neural recordings suggest an increase in calcium hyperpolarization currents in the CPu and PFC of intervention mice (−D2/+VDR) when compared with the parkinsonian mice (−D2). These animals (−D2/+VDR) also recorded an improvement in spatial working memory and motor function versus the Parkinsonian mice (−D2). These outcomes suggest the role of CPu-PFC corticostriatal outputs in the motor-cognitive decline seen in parkinsonian mice. Similarly, VDRA reduced the neural deficits through restoration of calcium currents (burst activities) in the intervention mice (−D2/+VDR). Conclusion: VDRA treatment reduced the motor-cognitive defects observed in haloperidol induced PD. Our findings suggest the role of VDRA in restoration of calcium currents associated with PFC and CPu corticostriatal outputs seen as burst frequencies in in vivo neural recording

    Acetaminophen Induces Mitochondrial Permeability Transition in Rats Without Causing Necrotic Liver Damage

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    Mitochondrial Permeability Transition (MPT) is reported as the mechanism of acetaminophen induced hepatic damage, however, rat models are resistant to acetaminophen induced toxicity. The occurrence and degree of mitochondrial permeability transition after treatment with 400 mg kgG1 of acetaminophen in albino Wistar rats were assessed. Animals were randomly distributed into seven groups; control, 12, 24, 36, 48, 60 and 72 h based on varying time (in hour) post acetaminophen prior to sacrifice after treatment. Mitochondrial Membrane Permeability Transition (MMPT) pore opening and mitochondrial cytochrome c release were estimated. Opening of MMPT pore and cytochrome c release were observed in 12, 24, 36 and 72 h, when compared with the control group. Liver function and histological results indicated no liver damage. It is concluded that toxic dose of acetaminophen induced mitochondrial permeability transition in rat hepatic tissues without leading to necrotic damage suggesting that rat hepatic tissues evade damage by mechanisms downstream of MPT

    Vitamin D 3 Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor Function in –D 2 R Tardive Dyskinesia Mice Model

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    Haloperidol-induced dyskinesia has been linked to a reduction in dopamine activity characterized by the inhibition of dopamine receptive sites on D2-receptor (D2R). As a result of D2R inhibition, calcium-linked neural activity is affected and seen as a decline in motor-cognitive function after prolonged haloperidol use in the treatment of psychotic disorders. In this study, we have elucidated the relationship between haloperidol-induced tardive dyskinesia and the neural activity in motor cortex (M1), basal nucleus (CPu), prefrontal cortex (PFC) and hippocampus (CA1). Also, we explored the role of Vitamin D3 receptor (VD3R) activation as a therapeutic target in improving motor-cognitive functions in dyskinetic mice. Dyskinesia was induced in adult BALB/c mice after 28 days of haloperidol treatment (10 mg/Kg; intraperitoneal). We established the presence of abnormal involuntary movements (AIMs) in the haloperidol treated mice (−D2) through assessment of the threshold and amplitude of abnormal involuntary movements (AIMs) for the Limbs (Li) and Orolingual (Ol) area (Li and Ol AIMs). As a confirmatory test, the dyskinetic mice (−D2) showed high global AIMs score when compared with the VD3RA intervention group (−D2/+VDR) for Li and Ol AIMs. Furthermore, in the behavioral tests, the dyskinetic mice exhibited a decrease in latency of fall (LOF; Rotarod-P < 0.05), climbing attempts (Cylinder test; P < 0.05) and latency of Turning (Parallel bar test; LOT-P < 0.05) when compared with the control. The reduced motor function in dyskinetic mice was associated with a decline in CPu-CA1 burst frequencies and an increase in M1-PFC cortical activity. However, after VD3RA intervention (−D2/+VDR), 100 mg/Kg for 7 days, CPu-CA1 burst activity was restored leading to a decrease in abnormal movement, and an increase in motor function. Ultimately, we deduced that VD3RA activation reduced the threshold of abnormal movement in haloperidol induced dyskinesia

    Vitamin D 3 Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor - Cognitive Function in − D 2 R Parkinsonian Mice Model

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    fourth generation antipsychotics have been implicated in the blockade of calcium signalling through inhibition of dopamine receptive sites on dopaminergic D 2 Receptor (D 2 R). As a result of the abnormal calcium signalling associated with D 2 R inhibition, changes occur in the m o- tor and memory neural axis leading to the observed behavioural deficits after prolonged halope r- idol. Thus, Vitamin D 3 receptor (VD 3 R), a calcium controlling receptor in the striatum can be ta r- geted to relief the neurological symptoms associated with haloperidol ( − D 2 R) induced PD. Aim: This study sets to investigate the role of VD3R activation in vitro and in vivo after haloperidol - induced Dopaminergic (D 2 R) blockade. In addi tion, we examined the associated neural activity and behavioural changes in parkinsonian and VDRA intervention mice. Methods: Dopaminergic D 2 R inhibition was investigated in vitro using Melanocytes isolated from the scale of a Tilapia. In four separate set ups, the cells were cultured in calcium free Ringer’s solution as follows; 300 ÎŒM haloperidol, 100 ÎŒM VD 3 , 100 mM calcium chloride and a combination of 300 ÎŒM haloperidol and 100 ÎŒM VD 3 . Subsequently, dopaminergic vesicle accumulation and calcium signalling were observed in bright field microscopy using blue and green fluorescence probes. In the second phase, PD was induced in adult BALB/c mice ( − D 2 ; n = 8) after 14 days of intraperitoneal haloperidol treatment (10 mg/Kg). A set of n = 4 mice were untreated ( − D 2 ) while the other group (n = 4) r e- ceived 100 mg/Kg of VD 3 for 7 days ( − D 2 /+VDR). The control groups (n = 4 each) were treated with normal saline (NS) and VD 3 (+VDR) fo r 14 days. At the end of the treatment phase, the animals were assessed in Rotarod, parallel bar - , cylinder - , Y - Maze - , one trial place recognition - and novel object recognition - (NOR) tests. Neural activity was measured using chronic electrode implants plac ed in the M1 (motor cortex), CPu (striatum), CA1 (hippocampus) and PFC (prefrontal cortex). Neural activity was compared with the outcomes of behavioural tests for memory and motor fun c- tions and data was expressed as mean ± SEM (analysed using ANOVA with T ukey post - hoc test, significant level was set at 0.05). Results/Discussion: in vitro outcomes show that VDR increase calcium signalling and reverses the effect of haloperidol; specifically by reducing dopaminergic vesicle accumulation in the cell body. Sim ilarly, in vivo neural recordings suggest an increase in calcium hyperpolarization currents in the CPu and PFC of intervention mice ( − D 2 /+VDR) when compared with the parkinsonian mice ( − D 2 ). These animals ( − D 2 /+VDR) also recorded an i m- provement in spatial working memory and motor function versus the Parkinsonian mice ( − D 2 ). These outcomes suggest the role of CPu - PFC corticostriatal outputs in the motor - cognitive decline seen in parkinsonian mice. Similarly, VDRA reduced the neural deficits through restorati on of ca l- cium currents (burst activities) in the intervention mice ( − D 2 /+VDR). Conclusion: VDRA treatment reduced the motor - cognitive defects observed in haloperidol induced PD. Our findings suggest the role of VDRA in restoration of calcium currents assoc iated with PFC and CPu corticostriatal ou t- puts seen as burst frequencies in in vivo neural recording
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