1,268 research outputs found
Transcriptional factor influence on OTA production and the quelling attribute of Sirna on the OTA producing strains of Aspergillus section Nigri
This study determined the influence of some transcriptional factors on ochratoxin A production as well as investigates the quelling attributes of some designed siRNA on the OTA producing Aspergillus section Nigri using standard recommended techniques. Results obtained following comparison of the pks gene promoter sequences from 15 isolates depicts differences in length and homology with the pks gene ranging from 218bp in a strain of the Aspergillus niger to 700bp in Aspergillus carbonarius. The alignment of the pks gene promoter region revealed that six and two of the aligned genes have Aba A binding site corresponding to CATTCT and CATTCC respectively while Brl A binding site was absent in all the isolates. Pac C binding site corresponding to CCTGGC and GCCAAG was also found in two and three of the pks gene promoter region respectively. The three designed siRNA shows significant impact on OTA inhibitions with no significant statistical differences (80.9, 74.4 and 75.3% for pks_Ia, pks_Ib and pks_Ic respectively) (F= 3.830, p>0.05). It can be concluded that Are A and Aba A are potential enhancers for ochratoxin A biosynthesis and none of the investigated transcriptional factors is enough for the activation of ochratoxin A production. However, pks gene was seen as a good target gene for inactivation in order to develop efficient means for ochratoxin A control using RNA silencing technology.Key words: Transcriptional factors, Ochratoxin A, siRNA, Quelling , Aspergillus section Nigr
Biochemical and bacteriological profiles of asymptomatic bacteriuria among school children in Ago-Iwoye, Nigeria
Background: Asymptomatic bacteriuria (ASB) in children is a predisposing factor to symptomatic urinary tract infection (UTI) that may be complicated by blood stream infections if not appropriately treated with resultant mortality or morbidity. The objectives of this study are to determine the prevalence of ASB, and evaluate both biochemical and bacteriological characteristics of urine samples of primary school pupils in Ago-Iwoye, Ijebu North Local Government Area (LGA), Ogun State, Nigeria.Methodology: Three hundred and seventy-two (186 males and 186 females) apparently healthy (asymptomatic) pupils aged 2-16 years from four randomly selected primary schools in the LGA were screened for ASB. Clean catch specimen of midstream urine was collected from each subject. Biochemical analysis of the urine was performed with Combi 10 reagent strip. MacConkey and Cysteine Lactose Electrolyte Deficient (CLED) agar plates were inoculated with calibrated wireloop delivering 0.01 ml of urine for aerobic culture at 37oC for 24 hours. Identification of significant bacteria on culture plates was done using conventional biochemical tests.Results: The frequency of clear, slightly turbid and turbid urine were 31 (8.3%), 99 (26.6%) and 56 (15.1%) respectively. All analyzed urine samples were alkaline and negative for ketone, glucose and blood, but contained protein in 230 (61.8%), bilirubin in 184 (49.5%), nitrites in 64 (17.2%) and urobilinogen in 14 (3.7%) subjects. The prevalence of significant bacteriuria was 11.8% (44 of 372) with 7.0% in males and 16.7% in females (p = 0.0063). The frequency of bacteria isolated in descending order were Escherichia coli 61.4%, Staphylococcus saprophyticus 61.4%, Staphylococcus aureus 45.5%, Bacillus subtilis 45.5%, Enterococcus faecalis 43.2%, Enterobacter spp 36.4%, Serratia marscencen 31.8%, Klebsiella pneumoniae 22.7%, Proteus mirabilis 22.7% and Pseudomonas aeruginosa 20.5%.Conclusion: This result highlights the presence of significant bacteriuria among apparently healthy pupils in the study area, with higher prevalence in the female pupils. The apparent risk of developing symptomatic UTI with the attendant complications in these pupils should spur preventive education of parents/guardians and the general populace about this entity.Keywords: Asymptomatic bacteriuria, S. saprophyticus, morbidity, prevalence, primary school pupil
Index to Studia Aethiopica
Index to Verena Böll, Denis Nosnitsin, Thomas Rave, Wolbert Smidt and Evgenia Sokolinskaia (eds.), Studia Aethiopica. In Honour of Siegbert Uhlig on the Occasion of his 65th Birthday, Harrassowitz Verlag: Wiesbaden 2004, 459 pp
Population receptive field estimates of human auditory cortex.
Here we describe a method for measuring tonotopic maps and estimating bandwidth for voxels in human primary auditory cortex (PAC) using a modification of the population Receptive Field (pRF) model, developed for retinotopic mapping in visual cortex by Dumoulin and Wandell (2008). The pRF method reliably estimates tonotopic maps in the presence of acoustic scanner noise, and has two advantages over phase-encoding techniques. First, the stimulus design is flexible and need not be a frequency progression, thereby reducing biases due to habituation, expectation, and estimation artifacts, as well as reducing the effects of spatio-temporal BOLD nonlinearities. Second, the pRF method can provide estimates of bandwidth as a function of frequency. We find that bandwidth estimates are narrower for voxels within the PAC than in surrounding auditory responsive regions (non-PAC)
Natural relations among physical observables in the neutrino mass matrix
We find all possible relations among physical observables arising from
neutrino mass matrices that describe in a natural way the currently observed
pattern (tan_23 and tan_12 large, dm^2_Sun/dm^2_Atm and tan_13 small) in terms
of a minimum number of parameters. Natural here means due only to the relative
smallness (vanishing) of some parameters in the relevant lagrangian, without
special relations or accidental cancellations among them.Comment: 14 pages, 1 eps figur
Forecasting of arecanut market price in north eastern India: ARIMA modelling approach
The paper deals with forecasting of minimum, maximum and average arecanut (Areca catechu L.) prices in the major arecanut markets of the Assam as well as Meghalaya based on the monthly price data. Monthly minimum, maximum, and average market price data of arecanut (in Rs./quintal) for the period May-2003 to March-2012 (for Assam) and February-2003 to March-2012 (for Meghalaya) were used. Box-Jenkins autoregressive integrated moving average (ARIMA) methodology was adopted for developing the models. An interrupted time-series model was also applied to resolve the problem of intervention point (October-2011) for Meghalaya price data. The proposed models were ARIMA (1, 0, 1), ARIMA (1, 1, 1), ARIMA (0, 1, 1) (for Assam market price data series) and, log ARIMA (0, 1, 1), log ARIMA (1, 0, 1) with linear trend and a man-made intervention (Oct-2011) and log ARIMA (0, 1, 1) with linear trend and a manmade intervention (Oct-2011) (for Meghalaya market price data series) for minimum, maximum, and average monthly price series, respectively
Recommended from our members
Human red blood cells at work: identification and visualization of erythrocytic eNOS activity in health and disease
A nitric oxide synthase (NOS)-like activity has been demonstrated in human red blood cells (RBCs), but doubts about its functional significance, isoform identity and disease relevance remain. Using flow cytometry in combination with the NO-imaging probe DAF-FM we find that all blood cells form NO intracellularly, with a rank order of monocytes > neutrophils > lymphocytes > RBCs > platelets. The observation of a NO-related fluorescence within RBCs was unexpected given the abundance of the NO-scavenger oxyhemoglobin. Constitutive normoxic NO formation was abolished by NOS inhibition and intracellular NO scavenging, confirmed by laser-scanning microscopy and unequivocally validated by detection of the DAF-FM reaction product with NO using HPLC and LC-MS/MS. Employing immunoprecipitation, ESI-MS/MS-based peptide sequencing and enzymatic assay we further demonstrate that human RBCs contain an endothelial NOS (eNOS) that converts L-3H-Arginine to L-3H-Citrulline in a Ca2+/Calmodulin-dependent fashion. Moreover, in patients with coronary artery disease, red cell eNOS expression and activity are both lower than in age-matched healthy individuals and correlate with the degree of endothelial dysfunction. Thus, human RBCs constitutively produce NO under normoxic conditions via an active eNOS isoform the activity of which is compromised in patients with coronary artery disease
The Wadi Faynan Project, Southern Jordan: a Preliminary Report on Geomorphology and Landscape Archaeology
Reproduced with permission of the publisher. © 1997 Council for British Research in the Levant. Details of the publication are available at: http://www.cbrl.org.uk/Publications/publications_default.shtmThe Wadi Faynan Project of the British Institute at Amman for Archaeology and History (BIAAH) has as its principal objective the provision of a detailed case study in the relationship between environmental change and human history in the arid zone, from prehistory to the present day. This report describes the preliminary findings of an initial campaign of fieldwork in geomorphology and landscape archaeology conducted by an inter-disciplinary team in 1996. A preliminary sequence of fluvial events has been established, represented by the Ghuwayr and Shayqar Beds dated to the Late Pleistocene, and the Faynan and Dana Beds dated to the Holocene. Methodologies have been trialed for recording, dating and interpreting the ancient field system assumed to be of Nabataean, Roman and Byzantine date; initial findings confirm its longevity of use and complexity of purpose. There are also indications that floodwater farming began in the Wadi Faynan in the Chalcolithic or Early Bronze Ag
Onset of fluidization in vertically shaken granular material
When granular material is shaken vertically one observes convection, surface
fluidization, spontaneous heap formation and other effects. There is a
controversial discussion in literature whether there exists a threshold for the
Froude number below which these effects cannot be
observed anymore. By means of theoretical analysis and computer simulation we
find that there is no such single threshold. Instead we propose a modified
criterion which coincides with critical Froude number for small
driving frequency .Comment: 7 pages, 5 figure
Hard rock landforms generate 130 km ice shelf channels through water focusing in basal corrugations
This work is licensed under a Creative Commons Attribution 4.0 International License.Satellite imagery reveals flowstripes on Foundation Ice Stream parallel to ice flow, and meandering features on the ice-shelf that cross-cut ice flow and are thought to be formed by water exiting a well-organised subglacial system. Here, ice-penetrating radar data show flow-parallel hard-bed landforms beneath the grounded ice, and channels incised upwards into the ice shelf beneath meandering surface channels. As the ice transitions to flotation, the ice shelf incorporates a corrugation resulting from the landforms. Radar reveals the presence of subglacial water alongside the landforms, indicating a well-organised drainage system in which water exits the ice sheet as a point source, mixes with cavity water and incises upwards into a corrugation peak, accentuating the corrugation downstream. Hard-bedded landforms influence both subglacial hydrology and ice-shelf structure and, as they are known to be widespread on formerly glaciated terrain, their influence on the ice-sheet-shelf transition could be more widespread than thought previously.NASA grant # NNX10AT68GANT # NT-0424589University of KansasUK NERC AFI grant NE/G013071/
- …