Spatio-temporal Variability of Landuse Landcover and its Impact on Land Surface Temperature in Zaria Metropolis, Nigeria

This paper assessed the spatio-temporal variability of land use land cover (LULC) and its impact on Land Surface Temperature (LST) in Zaria and environs. Multi-temporal Landsat data; Landsat 5TM, 7ETM+ and 8OLI of 1988, 2003 and 2018, respectively, at an interval of 15 years were obtained. These data were processed and classified into various classes using the supervised classification. It was also used to determine the LST of the area. The results of the classification revealed that, apart from built-up area which increased consistently from 15.353 km2 in 1988 to 32.8623km2 in 2018, all other LULC decreased within the study period. The LST ranges from 1.5 to 35.9ºC across the study period. The relationship between LULC and LST was investigated and result showed that LST had positive correlation of 0.608 with built-up area indicating that LST increased with increase in built-up areas. However, dense vegetation, light vegetation and bare land had negative correlations of -0.976, -0.851 and -0.708, respectively, with LST indicating that LST increase with decrease in vegetation and bare land. The implication of this unprecedented changes is the resulting environmental and climatic problems such as urban heat island and desertification which have become very common in the study area. It was suggested that the LULC of Zaria metropolis should be controlled and afforestation be encouraged to enhance a healthy living condition of the area. Keywords: Land Surface Temperature, Land Use Land Cover Change, Landsa

Phyllosilicate Transitions in Ferromagnesian Soils: Short-Range Order Materials and Smectites Dominate Secondary Phases

Analyses of X-ray diffraction (XRD) patterns taken by the CheMin instrument on the Curiosity Rover in Gale crater have documented the presence of clay minerals interpreted as smectites and a suite of amorphous to short-range order materials termed X-ray amorphous materials. These X-ray amorphous materials are commonly ironrich and aluminum poor and likely some of them are weathering products rather than primary glasses due to the presence of volatiles. Outstanding questions remain regarding the chemical composition and mineral structure of these X-ray amorphous materials and the smectites present at Gale crater and what they indicate about environmental conditions during their formation. To gain a better understanding of the mineral transitions that occur within ferromagnesian parent materials, we have investigated the development of secondary clay minerals and shortrange order materials in two soil chronosequences with varying climates developing on ultramafic bedrock. Field Sites: We investigated soil weathering within two field locations, the Klamath Mountains of Northern California, and the Tablelands of Newfoundland, Canada. Both sites possess age dated or correlated recently deglaciated soils and undated but substantially older soils. In the Klamath mountains the Trinity Ultramafic Body was deglaciated roughly 15,000 years bp while in the Tablelands a moraine was dated to about 17,600 years bp. The Klamath Mountains feature a seasonally wet and dry climate while the Tablelands are wet year-round with saturated soil conditions observed during sampling and standing water observed within 3 of 4 soil pit sampling locations

Spatial Multi-Criteria Analysis for Mapping of Flood Vulnerable Areas in Fagge Local Government Area of Kano State, Nigeria

Flood occurrences are common in various communities and efforts need to be doubled to abate the effect of flood on the populace. This paper used Multi-Criteria Analysis (MCA) in a Geospatial Information System (GIS) environment to identify and map areas vulnerable to flood in Fagge Local Government Area of Kano State. The causative factors of flood in the study area that include rainfall, soil, slope, elevation, geology, land use and drainage system were first identified and analysed using MCA to reveal the most effective factors of flood in the area. The results showed that elevation having the weight of 0.24 was the most effective factor contributing to flood in the area. This was followed by drainage (0.17), slope (0.168), soil (0.167) and Land Use Land Cover (LULC) (0.14). The result also revealed that, the least factors contributing to flood in the area were rainfall and geology having weights of 0.09 and 0.12, respectively. Vulnerability analysis showed that areas on the eastern parts of the study area were extremely vulnerable to flood while north-western and southern parts of the area were least vulnerable. It was therefore suggested that, the drainages should be constructed and the existing ones be cleared of blockages to allow free movement of storm waters away from the affected areas.Keywords: Flood Vulnerability, Geospatial Information System, Mapping and Multi Criteria Analysi

Geospatial Mapping and Multi-criteria Evaluation of Surrounding Flood Risk Communities of Usman Dam Abuja-Nigeria

There is concern of flood increase in recent decades due to its effect on human life and man’s environment. This study thus mapped and analysed flood risk communities around the Usman dam in Abuja, Nigeria, using geospatial techniques. Spatial data were captured which included positional coordinates, Landsat enhanced thematic mapper (ETM), soil map, and shuttle radar topographic mission (SRTM). The factors of flooding and their effect on the area under study were identified. The results of the study revealed based on the criteria weights that, slope (0.24) and elevation (0.24) were the most important factors contributing to flooding in the study area followed by drainage proximity (0.16), land use land cover (LULC)(0.12), and soil (0.08), respectively. The results also showed that, the built-up area, farmland, forest, grassland, rock outcrop and water body covered about 278.0 km2, 306.9 km2, 1406.6 km2, 1635.8 km2, 387.5 km2 and 386.9 km2, respectively of the study area. Moreover, it was found out that 6.41% of the settlements were located in the highly vulnerable areas, while 64.02% were located within the areas moderately vulnerable to flooding. However, the remaining 29.57% were located in the low vulnerable areas. It was suggested based on the results of the study that settlements close to the river course and dam reservoir, and along the flood plains should be relocated to the low vulnerable areas (eastern parts of the study area) in order to prevent future flood hazard. Keywords: Environment, Flood Risk Management, Geo-spatial Mapping, Hazard, Multi-criteria Analysi

Relativistic effects on the nuclear magnetic shielding tensor

A new approach for calculating relativistic corrections to the nuclear magnetic shieldings is presented. Starting from a full relativistic second order perturbation theory expression a two-component formalism is constructed by transforming matrix elements using the elimination of small component scheme and separating out the contributions from the no-virtual pair and the virtual pair part of the second order corrections to the energy. In this way we avoid a strong simplification used previously in the literature. We arrive at final expressions for the relativistic corrections which are equivalent to those of Fukui et al. J. Chem Phys. 105, 3175 (1996) and at some other additional terms correcting both the paramagnetic and the diamagnetic part of the nuclear magnetic shielding. Results for some relativistic corrections to the shieldings of the heavy and light nuclei in HX and CHȝX (X=Br,I) at both random phase and second order polarization propagator approach levels are given.Fil: Melo, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Ruiz de Azua, Martín César. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Giribet, Claudia Gloria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Aucar, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; ArgentinaFil: Romero, Rodolfo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentin

Semiconductor Nanowires Biosensors for Highly Selective and Multiplexed Detection of Biomolecules

The surface modification of Nano-structure has allowed specific and selective detection to be made on nano structures devices. Current study, a nanowire was surface engineered with the potential of silicon nanowires biosensors (SiO2) which enhance the biosensor activity especially identifying single-stranded bio-molecular such as E.coli DNA. The device's capabilities were studied based on it response n electrochemical activities of the terminal group of the surface modification agent. NH2 -terminated APTES) to provide rigid chemistry between the DNA organic and Si inorganic link of a biomolecule single_stranded ssDNA probe and SiO2_APTES link nanostructure. Thus, the study demonstrates that silicon nanowire sensing capability to discriminate molecular probe to that of molecule target of supra-genome 21 mers salmonella due to sensitive surface chemistries that made distinguishing the two species. The device captured the molecule precisely; the approach took the advantages of strong binding chemistry created between APTES and biomolecule. The results indicated how modifications of the nanowires provide sensing capability with strong surface chemistries that can lead to specific and selective target detection

Genetic, Phenotypic, and Interferon Biomarker Status in ADAR1-Related Neurological Disease

International audienceWe investigated the genetic, phenotypic, and interferon status of 46 patients from 37 families with neurological disease due to mutations in ADAR1. The clinicoradiological phenotype encompassed a spectrum of Aicardi–Goutières syndrome, isolated bilateral striatal necrosis, spastic paraparesis with normal neuroimaging, a progressive spastic dystonic motor disorder, and adult-onset psychological difficulties with intracranial calcification. Homozygous missense mutations were recorded in five families. We observed a p.Pro193Ala variant in the heterozygous state in 22 of 23 families with compound heterozygous mutations. We also ascertained 11 cases from nine families with a p.Gly1007Arg dominant-negative mutation, which occurred de novo in four patients, and was inherited in three families in association with marked phenotypic variability. In 50 of 52 samples from 34 patients, we identified a marked upregulation of type I interferon-stimulated gene transcripts in peripheral blood, with a median interferon score of 16.99 (interquartile range [IQR]: 10.64–25.71) compared with controls (median: 0.93, IQR: 0.57–1.30). Thus, mutations in ADAR1 are associated with a variety of clinically distinct neurological phenotypes presenting from early infancy to adulthood, inherited either as an autosomal recessive or dominant trait. Testing for an interferon signature in blood represents a useful biomarker in this context

Hypolithic and soil microbial community assembly along an aridity gradient in the Namib Desert

The Namib Dessert is considered the oldest desert in the world and hyperarid for the last 5 million years. However, the environmental buffering provided by quartz and other translucent rocks supports extensive hypolithic microbial communities. In this study, open soil and hypolithic microbial communities have been investigated along an East–West transect characterized by an inverse fog-rainfall gradient. Multivariate analysis showed that structurally different microbial communities occur in soil and in hypolithic zones. Using variation partitioning, we found that hypolithic communities exhibited a fog-related distribution as indicated by the significant East– West clustering. Sodium content was also an important environmental factor affecting the composition of both soil and hypolithic microbial communities. Finally, although null models for patterns in microbial communities were not supported by experimental data, the amount of unexplained variation (68–97 %) suggests that stochastic processes also play a role in the assembly of such communities in the Namib Desert.Web of Scienc

The relevance of fungi in astrobiology research – Astromycology

Since the very first steps of space exploration, fungi have been recorded as contaminants, hitchhikers, or as part of missions’ crews and payloads. Because fungi can cause human disease and are highly active decomposers, their presence in a space-linked context has been a source of major concern given their possible detrimental effects on crews and space structures. However, fungi can also be beneficial and be used for many space applications. The exact effects on fungi are not always clear as they possess high adaptability and plasticity, and their phenotypes and genotypes can undergo several changes under the extreme conditions found in space, thus leading to different results than those we would have on Earth. Understanding and analysing these aspects is the subject of astromycology, a research field within astrobiology. The impending situation of a resurgent space race is expected to boost astromycology’s visibility and importance. However, researchers lack both a framework and a solid base of knowledge from which to contextualise their work. This critical review addresses this gap by conceptualising the field of astromycology, covering key research and current questions pertaining to the field, and providing a relevant research instrument for future work