Natural & Applied Sciences

Natural & Applied Sciences Research Papers/Topics

Solvent Extraction Studies on Zn(II) AND Cd(II) Complexes OF 1,5-Dimethyl-2-Phenyl-4[(E)-(2,3,4- Trihydroxyphenyl)]DIAZENYL-1,2-Dihydroxyl-3hpyrazol-3-ONE.

ABSTRACT The azo-ligand, 1,5-dimethyl-2-phenyl-4-[(E)-(2,3,4-trihydroxylphenyl) diazenyl]- 1,2-dihydro-3H-pyrazol-3-one (H3L) and its Zn(II) and Cd(II) complexes have been synthesized and characterized based on stoichiometric, molar conductance, electronic and infra-red spectral studies. The results showed that H3L reacted with the metals in 2:1 ratio. H3L coordination was through the hydroxyl, azo and carbonyl groups to form [Zn(H2L)2] 2+ and [Cd(H2L)2] 2+ respectively. Solvent extraction s...

Influence of Seasonal Cattle Movement on Prevalence of Trypanosome Infections in Cattle in the Maasai Steppe, Tanzania

ABSTRACT Animal African Trypanosomosis is a Neglected Tropical Disease with significant impacts to pastoral community livelihoods. Our study sought to determine the influence of seasonal cattle movements on the prevalence of trypanosome infections in cattle in the pastoral areas of the Maasai Steppe. Identification of spatial and temporal dynamics of trypanosome infections in cattle is essential for designing effective control strategies. To identify potential hotspots of trypanosome transm...

The potential of Grateloupia filicina (Lamoureux) J. Agardh. for mariculture: Culture experiments and observations on shore phenology

Grateloupia filicina is a carrageenophytic red alga which is in demand as a carrageenan raw material and for use in food. There is therefore interest in developing a technique for mariculturing this species. Since vegetative propagation from thallus fragments has not been successful, the present study was initiated to determine suitable conditions for spore liberation and growth of G. filicina from spores. It was also attempted to propagate G. filicina sporelings from crust and thallus fragme...

A Report On Me Invasive Status Of Pinus Patula On Mount Mulanje, Mala Wi.

Natural regeneration of the Mexican weeping pine Pinus patula on Mt. Mulanje was investigated and found to represent a serious threat to the natural vegetation, with  the invasion already advanced on the north eastern plateaux. Various aspects of the biology of the pine are related to its success as an exotic invader on the mountain.  Perhaps most important is the ability of the species to cope with fire, and the role of  regular fires in enhancing the invasion. Urgent action is needed ...

Some Observations on the genus At~ocnemum

Only in 1954 the notes of late Prof. Moss on the genera Arthrocnemum and Salicornia l'Tere published, and although this was a big step forward in the classification of these genera, it proved to be unsatisfactory in many cases. This, however, should not throw the work on that subject done by him into shade, as shows his ealier works ( Moss, 19lo, 1912, 1914),and only his notes published by Prof. Adamson in 1954 w·ere unfortunately fragmentary. The revision of the genus Arthrocnemum is taken ...

Three Species Of The Genus Rhabdosargus Fowler, With Special Reference To The Ffwhite Stumpnose", R.Globiceps (Cuvier)

The Zoology Department of the u.c.T. has been making an ecological survey of South Afr1,can estuaries. The plant and animal lif'e of many estuaries has been studied in relation to physico-chemical conditions, and bottom fauna has been dealt with in great detail. Not much is known about the fish populations that occupy these estuaries. It was theref'·ore decided that some information about typical estuarine fish might be of use. For the first four months nettings were made at two estuaries ne...

"The Benthi~Ecology o~ FaJise Bay, w.ith Notes on the Analysis o~ Shallow-water So~t SUbstrata

This work continues the marine tradition o~ the Department o~ Zoology but attempts to open-up a new ~ield by tack].ing for· the first time the ecology of the shaJllow sea bed. False Bay is accessible and provides a large arem that is virtually unaffe.cted by rivers or the works of man. Its' situation happ:ens to be particularly _interesting. It is the nearest part of the flat, submarine shelf called the Agulhas Bank, where there are valuable fishing grounds: and it lies at the boi.mdary of t...

The Geology And Geochemistry Of The Etendeka Formation Quartz Latites, Namibia.

The Etendeka Formation volcanics of north-western Namibia form part of the Karoo Igneous Province of southern Africa and consist of a series of basalts interbedded with quartz latites and minor volumes of latite. This thesis examines various aspects of the geology and geochemistry of the quartz latites, in particular the volcanological and petrogenetic origin of these rocks . This study has involved the geological mapping of ca. 5000 km2 of the southern Etendeka region and the documentation o...

Correlation of Chemical Compositions of Cassava Varieties to Their Resistance to Prosiephanus truncatus Horn (Coleoptera: Bostrichidae)

ABSTRACT. The preference of cassava as a major host by Prostephonus truncotus Horn is a major c onstraint to ample production of cassava, tvumibot esculenta Crantz and storage. This study analyzed the nutritional and secondary metabolite compositions in 15 cassava varieties, evaluated levels of damage and reproduction by P. truncatus, and assessed their resistance to attack. One hundred grams 01 dried cassava chips in 250'ml Kilner jars were infested with 10 adult larger grain borerof 0-10 da...

A Tax~Omic And Lf.Pidological Study. Of ''Lhe .South African Heterosoma Ta With Special R.Eference To The Value Of Scale Characters • In Identification Amd Classification

During the course of some years of research into growth-rate and age of South African fishes of commercial importance, amongst wbich are included various species of Heterosomata, 1 the scales of sucb species received a great deal of attention.· In a very short time the characteristics of the sea les thus . examined became so familiar, that it was found poseible to identify any particular species solely from its scales. In a great many instances scale-samples, labelled with the local common n...

Cytokine profiles and antibody responses to Plasmodium falciparum malaria infection in individuals living in Ibadan, southwest Nigeria

Abstract Background: The ability of the host immune system to efficiently clear Plasmodium falciparum parasites during a malaria infection depends on the type of immune response mounted by the host. Study design: In a cross-sectional study, we investigated the cellular-and antibody responses in individuals with P. falciparum infection, in an attempt to identify immunological signs indicative of the development of natural immunity against malaria in Ibadan, Nigeria. Levels of IL-10, IL-12(p70)...

The Hydroclimate Variability of Central Africa: seasonal cycle, mechanisms, teleconnections and impacts on neighbouring regions

Abstract Central Africa is, climatologically speaking, a poorly studied region (Clivar, 2000; Dezfuli and Nicholson, 2012; Nicholson and Dezfuli, 2012; Todd and Washington, 2004). It is considered as a knowledge gap in the understanding of the tropical climate system (Todd and Washington, 2004). Drivers of Central Africa rainfall are not well documented and deserve more attention. The aims of thesis are to enhance our fundamental understanding of Central Africa rainfall and the mechanisms inv...

TECTONIC AND SEDIMENTARY HISTORY OF THE MID NATAL VALLEY (S.W. INDIAN OCEAN)

ABSTRACT The Natal Valley is a sediment-filled marine basin situated between the east coast of southern Africa (Natal) and the Mozambique Ridge. Geophysical and sedimentological t~chniques are used in a broad geological study of the mid Natal Valley. Major emphasis is directed to: (a) basin history and tectonic evolution; (b) seismic stratigraphy of the basin fill; (c) recent sedimentary processes and responses. General basin morphology is defined by five major physiographic provinces: contin...

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PSN Africa 589 PAGES (126634 WORDS) Geology Thesis
A NOTE ON AN ABNORMAL XENOPUS LAEVIS SPECIMEN WITHOUT HAEMOGLOBIN and on some~eriments performed as a consequence.

In the blood vascular system of a typical fish, the blood is sent from the heart to the gills for oxygenation and thence to the rest of the tissues, before returning once more to the heart. This is a so-called "Single Circulation". Where lungs make their appearance in the vertebrate series however, their blood supply is derived from the last of the aortic arches and is returned via the newly formed pulmonary veins, directly to the heart. A part of the blood leaving from the heart is sent to t...

Total immunoglobulin G and IgG1 subclass levels specific for the MSP-119 of Plasmodium falciparum are different in individuals with either processing-inhibitory, blocking or neutral antibodie

Abstract Background: Some MSP-119 specific antibodies that inhibit merozoite invasion also inhibit the secondary processing of MSP-1. However the binding of these inhibitory antibodies can be blocked by another group of antibodies, called blocking antibodies, which recognize adjacent or overlapping epitopes, but themselves have no effect on either MSP-1 processing or merozoite invasion. These antibodies have been reported to be present in individuals living in a malaria endemic area. Methods:...


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