1,555 research outputs found
Contributions of the seasonal and long term flood patterns of River Niger to the development and control of water hyacinth (Eichhornia crassipes) in Kainji Lake, Nigeria
(6 page document
Molecular and enological characterization of autochthonous <i>Saccharomyces cerevisiae</i> strains isolated from grape-musts and wines Cannonau
Fermentation by autochthonous yeasts may produce wines with enological properties that are unique of a specific area or variety of grape must. In order to identify yeast starter strains for the production of the Sardinian wine Cannonau DOC, 66 Saccharomyces cerevisiae strains, isolated from musts and wines Cannonau of six vitivinicole areas in Sardinia, were subjected to enological characterization and molecular identification. The RFLP-PCR fingerprinting of the ITS region of rRNA (ITS1-5,8S- ITS2) as well as ethanol, foam, and H2S production were analysed
Total Factor Productivity Growth and Employment: A Simultaneous Equations Model Estimate
This paper provides a structural estimation of the recent model proposed by Pissarides and Vallanti, a simplified equilibrium model which draws heavily on models with frictions and quasi-rents. The structural model is a system of three equations. The estimation method is a three-stage least squares. My empirical results find that although faster TFP growth temporarily decreases employment, most likely be- cause job destruction reacts faster to schocks than job creation does, after the first year I do not find any statistically significant effect of growth on employment
“Experimental study on water pollution tendencies around Lobuliet, Khor bou and Luri streams in Juba, South Sudan
Urbanization and population demand for resources in Juba has led to pollution of aquatic ecosystems and deteriorated water quality. The streams water samples in Juba, central equatoria state, were collected in sterile 500ml plastic containers and instantaneously experimented. The pH, total solids, total dissolved solids, alkalinity and nitrate were used for evaluation. The results were then compared with standard permissible limits. The pH for Khor bou and Luri streams ranges from 6.1 to 6.7. Lobuliet stream showed abnormal pH value ranging from 9.7 to 9.9. Alkalinity ranges from 106.67 to 1060.33 mg/l. Total dissolved solids (TDS) ranges from 0.002mg/ml to 20.00mg/l.
Statistical analysis using ANOVA indicated that TDS was insignificantly different (p>0.05) among the sites sampled.
The nitrite level was low ranging from 0.04mg/l to 0.09mg/l. The cadmium and lead concentration ranges from 0.86mg/l to 1.92mg/l and 0.29mg/l to 0.95mg/l respectively. Analysis of variance showed the concentration of cadmium and lead were significantly different (P<0.05) among the sites sampled. Lobuliet stream had the highest concentration of heavy metals. The study concluded that pollution tendencies were attributed to the discharge of municipal and industrial effluent to the streams and if not properly tackled, may pose adverse impacts to the
biogeochemical cycle
Marketing and distribution of fish from Lake Chad
This study provides information on fish quantities, economic data and flows of Doro fish market near Baga, Nigeria, known as the major fish market on the Nigeria section of the Lake Cha
A small molecule ApoE4-targeted therapeutic candidate that normalizes sirtuin 1 levels and improves cognition in an Alzheimer's disease mouse model.
We describe here the results from the testing of a small molecule first-in-class apolipoprotein E4 (ApoE4)-targeted sirtuin1 (SirT1) enhancer, A03, that increases the levels of the neuroprotective enzyme SirT1 while not affecting levels of neurotoxic sirtuin 2 (SirT2) in vitro in ApoE4-transfected cells. A03 was identified by high-throughput screening (HTS) and found to be orally bioavailable and brain penetrant. In vivo, A03 treatment increased SirT1 levels in the hippocampus of 5XFAD-ApoE4 (E4FAD) Alzheimer's disease (AD) model mice and elicited cognitive improvement while inducing no observed toxicity. We were able to resolve the enantiomers of A03 and show using in vitro models that the L-enantiomer was more potent than the corresponding D-enantiomer in increasing SirT1 levels. ApoE4 expression has been shown to decrease the level of the NAD-dependent deacetylase and major longevity determinant SirT1 in brain tissue and serum of AD patients as compared to normal controls. A deficiency in SirT1 level has been recently implicated in increased tau acetylation, a dominant post-translational modification and key pathological event in AD and tauopathies. Therefore, as a novel approach to therapeutic development for AD, we targeted identification of compounds that enhance and normalize brain SirT1 levels
Protocorks and monopole Floer homology
We introduce and study a class of compact 4-manifolds with boundary that we
call protocorks. Any exotic pair of simply connected closed 4-manifolds is
related by a protocork twist, moreover, any cork is supported by a protocork.
We prove a theorem on the relative Seiberg-Witten invariants of a protocork
before and after twisting and a splitting theorem on the Floer homology of
protocork boundaries. As a corollary we improve a theorem by Morgan and
Szab\'{o} regarding the variation of Seiberg-Witten invariants with an upper
bound which depends only on the topology of the data. Moreover, we generalize
the result that only the reduced Floer homology of a cork boundary contributes
to the variation of the Seiberg-Witten invariants under a cork twist to more
general cut and paste operations where the pieces involved are -connected
and homeomorphic relative to the boundary.Comment: 1) Strengthened Corollary 1.3. 2) The proof of Theorem 1.1.(b) is now
independent from the results on moduli spaces of reducible monopoles of
Section 5 so the proof of Theorem.1.1 depends only on formal properties of
Floer homology. The results of Sections 5 are now presented in the
introductio
Imaging of SNR IC443 and W44 with the Sardinia Radio Telescope at 1.5 GHz and 7 GHz
Observations of supernova remnants (SNRs) are a powerful tool for
investigating the later stages of stellar evolution, the properties of the
ambient interstellar medium, and the physics of particle acceleration and
shocks. For a fraction of SNRs, multi-wavelength coverage from radio to ultra
high-energies has been provided, constraining their contributions to the
production of Galactic cosmic rays. Although radio emission is the most common
identifier of SNRs and a prime probe for refining models, high-resolution
images at frequencies above 5 GHz are surprisingly lacking, even for bright and
well-known SNRs such as IC443 and W44. In the frameworks of the Astronomical
Validation and Early Science Program with the 64-m single-dish Sardinia Radio
Telescope, we provided, for the first time, single-dish deep imaging at 7 GHz
of the IC443 and W44 complexes coupled with spatially-resolved spectra in the
1.5-7 GHz frequency range. Our images were obtained through on-the-fly mapping
techniques, providing antenna beam oversampling and resulting in accurate
continuum flux density measurements. The integrated flux densities associated
with IC443 are S_1.5GHz = 134 +/- 4 Jy and S_7GHz = 67 +/- 3 Jy. For W44, we
measured total flux densities of S_1.5GHz = 214 +/- 6 Jy and S_7GHz = 94 +/- 4
Jy. Spectral index maps provide evidence of a wide physical parameter scatter
among different SNR regions: a flat spectrum is observed from the brightest SNR
regions at the shock, while steeper spectral indices (up to 0.7) are observed
in fainter cooling regions, disentangling in this way different populations and
spectra of radio/gamma-ray-emitting electrons in these SNRs.Comment: 13 pages, 9 figures, accepted for publication to MNRAS on 18 May 201
- …
