Onion Cultivation System and Spatial Distribution Centers in Tahoua Region/Niger

Indiana University-Purdue University Indianapolis (IUPUI)Onion farming is the main irrigated crop that contributes to the economy of the Tahoua region, Niger. There are two factors that promote the outstanding potentialities of onion cultivation in Niger: the best productive variety “Violet Galmi”, and it is well adapted to storage. It is produced during both growing seasons which creates a permanent local supply of onions all year. Much of the producing areas are not accessible by road, which inhibits the marketing network. Farmers are in need of an improved transportation system in order to further develop onion production. The Violet of Galmi is grown by all the onion producers of Niger. This onion has a major importance in the socio-economic life of the Nigerien population. The consumers appreciate its cooking qualities and spicy taste. It also has a commercial advantage in the local and the sub-regional markets

Depth to magnetic sources determination using Source Parameter Imaging (SPI) of aeromagnetic data of parts of Central and North-Eastern Nigeria: a reconnaissance tool for geothermal exploration in the area

Source Parameter Imaging (SPI) of aeromagnetic data covering an area located approximately between latitude 7.5o N and 11.5o N and longitude 7.5o E and 10.5o E, which corresponds to parts of the Benue trough (lower part of the Upper Benue trough, the entire middle Benue trough, and upper part of the Lower Benue trough), lower part of the Gongola and Yola Basins, the Precambrian Basement, the Jurassic Younger Granites and two prominent hot Springs, Wiki hot spring in Bauchi state (in the north-eastern part) and Akiri hot spring in Nasarawa state (in the south-western part) of central and north-eastern Nigeria, was carried out for the purpose of estimating the depth to magnetic basement of the area. The estimated depths to magnetic sources from Source parameter imaging (SPI), range from 0.12 to 12.26 km. The highest depth can be found at the south-western part of the study area. The depth to magnetic basement is shallower mainly in the north and extreme north-eastern parts of the study area with magnetic high flanking areas of magnetic low. The above characteristics of these areas and the location of warm springs at the north-eastern and south-western parts of the study area (Wikki and Akiri hot springs respectively). Which suggests the occurrence of tectonic activities in the area, hence is an indication that, there might probably be good sources for geothermal and thereby recommended for both geothermal exploration and exploitation

Gross Alpha and Beta Radio Activity Concentrations and Estimated Committed Effective dose to the General Public Due to Intake of Groundwater in Mining Areas of Plateau State, North Central Nigeria

Tin mining activities carried out in parts of plateau state from the beginning of this century to the early 1980’s have left behind a post mining environment scarred by numerous mine pond and uncontrolled heaps of mine tailings containing radioactive minerals that have found their way into the natural water resources. In this study the gross activities of the alpha and beta emitting radionuclides present in the naturally occurring water bodies in the mining areas of plateau state covered by Naraguta sheet 168 were determined. Fifty-eight (58) groundwater, comprising of twenty-three (23) borehole and thirty-five (35) locally dug well samples were drawn randomly. The samples were analyzed and counted for gross alpha and beta activities using MPC-2000-DP. The results showed that the range of alpha activity varied from (0.110-1.580)Bq/l with a geometric mean of 0.328 Bq/l for borehole samples and (0.010-12.590)Bq/l with a geometric mean of 0.498 Bq/l for well water samples. The range of beta activity varied from (0.012-2.760) Bq/l with a geometric mean of 0.198 Bq/l for borehole water samples and (0.020-14.640) with the geometric mean of 0.366Bq/l for well water samples. Most of the samples show higher concentration above the WHO guideline value of 0.5Bq/l for alpha activity and 1.0Bq/l for beta activity. The annual committed effective (CED) to infants, children and adults were estimated. The results shared elevated values in most of the location above the ICRP acceptable standard of 0.1mSv/yr. The mean values of CED due to intake of borehole water for alpha activity are 0.240mSv/yr, 0.481mSv/yr and 0.885mSv/yr for infants, children and adult respectively. For beta activity the values are 0.201mSv/yr, 0.410 mSv/yr. and 0.820 mSv/yr. In the well water samples the mean CED value for alpha activity are 0.485 mSv/yr, 0.963 mSv/yr. and 1.938mSv/yr for infants, children and adults respectively and for beta activity the mean values are 0.594 mSv/yr., 1.187mSv/yr. and 2.375 mSv/yr. respectively. These values show that the general public in these locations are committed to higher dose above the standard values and long term exposure could pose health threat. Keywords: Gross alpha, gross beta, Mine tailings, water, Radionuclide

The Energy Landscape, Folding Pathways and the Kinetics of a Knotted Protein

The folding pathway and rate coefficients of the folding of a knotted protein are calculated for a potential energy function with minimal energetic frustration. A kinetic transition network is constructed using the discrete path sampling approach, and the resulting potential energy surface is visualized by constructing disconnectivity graphs. Owing to topological constraints, the low-lying portion of the landscape consists of three distinct regions, corresponding to the native knotted state and to configurations where either the N- or C-terminus is not yet folded into the knot. The fastest folding pathways from denatured states exhibit early formation of the N-terminus portion of the knot and a rate-determining step where the C-terminus is incorporated. The low-lying minima with the N-terminus knotted and the C-terminus free therefore constitute an off-pathway intermediate for this model. The insertion of both the N- and C-termini into the knot occur late in the folding process, creating large energy barriers that are the rate limiting steps in the folding process. When compared to other protein folding proteins of a similar length, this system folds over six orders of magnitude more slowly.Comment: 19 page

Analgesic and Anti-Inflammatory activities of Rothmannia Longiflora Salisb In Mice And Rats

Abstract: In this study, the analgesic and anti-inflammatory activities of the methanolic leaf extract of Rothmannialongiflora were investigated. The methanolic leaf extract of the plant at the doses of 250, 500, and 1000mg/kg orally was evaluated for analgesic activity using acetic acid-induced writhing test, hot plate test and formalin test. The anti-inflammatory potential of the extract was evaluated using carrageenan-induced paw oedema test in rats. The methanolic leaf extract exhibited significant dose dependent analgesic and antiinflammatory effects comparable to piroxicam (20mg/kg body weight orally), which is a standard analgesic and anti-inflammatory drug. The preliminary phytochemical screening of the methanolic leaf extract of Rothmannialongiflora revealed the presence of flavonoids, tannins, saponins, glycosides, steroids/terpanoids, and carbohydrates. The oral median lethal dose (LD 50 ) of the extract in mice and rats were found to be greater than 5000mg/kg, suggesting that the methanolic leaf extract of Rothmannialongiflora is non-toxic. The present findings suggest that the methanolic leaf extract of the plant possesses analgesic and anti-inflammatory activities, and supports the ethno medical claims of the use of the plant in the management of pain and inflammatory conditions

Protein folding on the ribosome studied using NMR spectroscopy

NMR spectroscopy is a powerful tool for the investigation of protein folding and misfolding, providing a characterization of molecular structure, dynamics and exchange processes, across a very wide range of timescales and with near atomic resolution. In recent years NMR methods have also been developed to study protein folding as it might occur within the cell, in a de novo manner, by observing the folding of nascent polypeptides in the process of emerging from the ribosome during synthesis. Despite the 2.3 MDa molecular weight of the bacterial 70S ribosome, many nascent polypeptides, and some ribosomal proteins, have sufficient local flexibility that sharp resonances may be observed in solution-state NMR spectra. In providing information on dynamic regions of the structure, NMR spectroscopy is therefore highly complementary to alternative methods such as X-ray crystallography and cryo-electron microscopy, which have successfully characterized the rigid core of the ribosome particle. However, the low working concentrations and limited sample stability associated with ribosome-nascent chain complexes means that such studies still present significant technical challenges to the NMR spectroscopist. This review will discuss the progress that has been made in this area, surveying all NMR studies that have been published to date, and with a particular focus on strategies for improving experimental sensitivity

Mechanical Bonds and Topological Effects in Radical Dimer Stabilization

While mechanical bonding stabilizes tetrathiafulvalene (TTF) radical dimers, the question arises: what role does topology play in catenanes containing TTF units? Here, we report how topology, together with mechanical bonding, in isomeric [3]- and doubly interlocked [2]catenanes controls the formation of TTF radical dimers within their structural frameworks, including a ring-in-ring complex (formed between an organoplatinum square and a {2+2} macrocyclic polyether containing two 1,5-dioxynaphthalene (DNP) and two TTF units) that is topologically isomeric with the doubly interlocked [2]catenane. The separate TTF units in the two {1+1} macrocycles (each containing also one DNP unit) of the isomeric [3]catenane exhibit slightly different redox properties compared with those in the {2+2} macrocycle present in the [2]catenane, while comparison with its topological isomer reveals substantially different redox behavior. Although the stabilities of the mixed-valence (TTF2)^(•+) dimers are similar in the two catenanes, the radical cationic (TTF^(•+))_2 dimer in the [2]catenane occurs only fleetingly compared with its prominent existence in the [3]catenane, while both dimers are absent altogether in the ring-in-ring complex. The electrochemical behavior of these three radically configurable isomers demonstrates that a fundamental relationship exists between topology and redox properties