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Gene Expression Differences In Hybrids At Beginning Of Speciation Continuum, Long A. Nicholas Aug 2016

Gene Expression Differences In Hybrids At Beginning Of Speciation Continuum, Long A. Nicholas

Biology Theses - Archive

The formation of new species results from reproductive isolation, or the barrier to successful mating between organisms of divergent populations. The degree of reproductive isolation can be measured by the reduction in fitness of hybrid offspring that can result from incompatibilities between the genotypes of each parent. In this study, genetic incompatibilities arising at the earliest stage of speciation are examined between intraspecific hybrids in which an effectively sterile hybrid phenotype termed “still” is observed at ~50% frequency in crosses between divergent populations of Tribolium castaneum. Timing and magnitude of gene expression regulation is examined at four stages of development, …


Naturally Occurring Mellein-Type 3,4-Dihydroisocoumarins And Related Lactones: Synthetic Approaches - A Review, Stephen Jm Mdachi Jul 2016

Naturally Occurring Mellein-Type 3,4-Dihydroisocoumarins And Related Lactones: Synthetic Approaches - A Review, Stephen Jm Mdachi

Tanzania Journal of Science

Mellein and its derivatives are the most common 3,4-dihydroisocoumarins and are known to exhibit an array of biological activities such as antibacterial, antifungal, antimalarial, antiallergic, antitumor, anti-inflammatory, antiulcer, pheromonal, plant growth-promoting and antileukemic activities. Other mellein derivatives are recognized phytotoxins, neurotoxins, hepatotoxins, nephrotoxins and teratogens. Consequently, considerable efforts have been directed at studying these natural products. While most of the reported studies have focused on the isolation, characterization and bioassay studies of melleins, a number of synthetic studies have also been reported. This paper focuses on synthetic approaches towards these biologically active and, thus, potentially useful natural products. The aim …


Identification Of Tanzanian Saprophytic Edible Mushrooms By Amplification And Sequencing Of Its/Lsu Regions Of Ribosomal Rna Operon, Ibrahim Juma, Anthony Manoni Mshandete, Donatha Damiani Tibuhwa, Amelia Kajumulo Kivaisi Jul 2016

Identification Of Tanzanian Saprophytic Edible Mushrooms By Amplification And Sequencing Of Its/Lsu Regions Of Ribosomal Rna Operon, Ibrahim Juma, Anthony Manoni Mshandete, Donatha Damiani Tibuhwa, Amelia Kajumulo Kivaisi

Tanzania Journal of Science

In this study, ten wild saprophytic edible mushrooms samples, collected from Tanzania natural forests and planted trees, and their two domesticated forms were characterized by in-vitro/in-vivo amplification and sequencing of ITS/LSU regions. Mushroom genomic DNA was extracted by ZR Fungal/Bacterial DNA MniPrep Kit. ITS and LSU regions were amplified using ITS-4/ITS-5 and LR16/LROR primers, respectively and sequenced. The amplicons with messy sequences were cloned. For analyzing recombinant E. coli DH5α cells, colony PCR and sequencing were done using M13-F/M13-R primers. The studied mushrooms were identified as Amylosporus sp. IJ-2014, Polyporales sp., Polyporus tenuiculus, Pleurotus cystidiosus, Laetiporus sp. IJ-2014, Lentinus sajor-caju, …


Spread Of Tylodelphys Mashonense (Digenea: Diplostomidae) By Grey Heron Ardea Cinerea And Great White Egret A. Alba In Lake Victoria, Tanzania, Fred D. Chibwana, Gamba Nkwengulila Jul 2016

Spread Of Tylodelphys Mashonense (Digenea: Diplostomidae) By Grey Heron Ardea Cinerea And Great White Egret A. Alba In Lake Victoria, Tanzania, Fred D. Chibwana, Gamba Nkwengulila

Tanzania Journal of Science

Despite the fact that Tylodelphys mashonense, parasites of the cranial cavity of the catfish Clarias gariepinus, are ubiquitous in freshwater systems, little is known on their spread. As such, we examined a total of 152 piscivorous birds, belonging to 6 species; 43 great cormorant Phalacrocorax carbo, 33 grey heron Ardea cinerea, 26 hamerkop Scopus umbretta, 22 great white egret Ardea alba, 15 marabou stork Leptoptilos crumeniferus and 13 pied kingfisher Ceryle rudis foraging in the Lake Victoria. Out of the six bird species only A. cinerea and A. alba were found infected by T. mashonense with prevalence of 42.4% and …


Variation Of Small Mammal Populations Across Different Habitat Types In The Serengeti Ecosystem, Flora J Magige Jul 2016

Variation Of Small Mammal Populations Across Different Habitat Types In The Serengeti Ecosystem, Flora J Magige

Tanzania Journal of Science

This study investigated the abundance and diversity of small mammals in cultivated land (unprotected area) and wooded grassland in the Serengeti National Park (protected area) in the Serengeti ecosystem. Small mammal populations were sampled through capture-mark-recapture trapping techniques in March-April 2010. A total of 896 trap nights covering wet season, 9 species of rodents and 1 species of soricomorphs (shrew family) were captured. Overall, Multimammate rat Mastomys natalensis (Smith) was by far the most abundant rodent in cultivated land (28%) while inside the park, shrew Crocidura sp., was high in numbers (8%). A significantly higher abundance (trap success) of small …


Ligninolytic Enzymes Of The Fungus Isolated From Soil Contaminated With Cow Dung, Rose J. Masalu Jul 2016

Ligninolytic Enzymes Of The Fungus Isolated From Soil Contaminated With Cow Dung, Rose J. Masalu

Tanzania Journal of Science

Lignin is the complex polymer and very few microorganisms are able to degrade it. The study aimed at isolating lignin degrading fungi from soil contaminated with cow dung using ligninolytic screening media. The study was able to isolate one ligninolytic fungus by using lignin media. The strain was screened for  production of ligninolytic enzymes  using Rhemazol Brilliant blue R (RBBR) dye, 2,2-azino-bis (3- ethylbenzthiazoline)-6-sulfonate (ABTS) and guaiacol in a semi-solid medium. The isolate decolourized RBBR dye, ABTS and guaiacol in a semi solid media. The strain was further tested for lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase (Lac) enzymatic …


A Novel Xenomonitoring Technique Using Mosquito Excreta/Feces For The Detection Of Filarial Parasites And Malaria, Nils Pilotte, Weam I. Zaky, Brian P. Abrams, Dave D. Chadee, Steven A. Williams Apr 2016

A Novel Xenomonitoring Technique Using Mosquito Excreta/Feces For The Detection Of Filarial Parasites And Malaria, Nils Pilotte, Weam I. Zaky, Brian P. Abrams, Dave D. Chadee, Steven A. Williams

Biological Sciences: Faculty Publications

Given the continued successes of the world’s lymphatic filariasis (LF) elimination programs and the growing successes of many malaria elimination efforts, the necessity of low cost tools and methodologies applicable to long-term disease surveillance is greater than ever before. As many countries reach the end of their LF mass drug administration programs and a growing number of countries realize unprecedented successes in their malaria interven- tion efforts, the need for practical molecular xenomonitoring (MX), capable of providing surveillance for disease recrudescence in settings of decreased parasite prevalence is increasingly clear. Current protocols, however, require testing of mosquitoes in pools of …


Traditional Medicinal Uses Of Small Mammal Products: A Case Study Of The African Savannah Hares, Crested Porcupines And Rock Hyraxes In Serengeti District, Tanzania, Flora John Magige Jul 2015

Traditional Medicinal Uses Of Small Mammal Products: A Case Study Of The African Savannah Hares, Crested Porcupines And Rock Hyraxes In Serengeti District, Tanzania, Flora John Magige

Tanzania Journal of Science

Traditional medicines, both plant and animal products, have been used to cure various diseases since time immemorial especially in rural areas worldwide. Many studies have focused on traditional plant products, but little research has been conducted on animal traditional medicines. This study investigated  the use of small mammal  products for medicinal purposes in three villages bordering Serengeti National Park in Serengeti District, Tanzania. A total of 71 respondents were interviewed in Kisangura, Nyamburi and Machochwe villages in November 2010, using questionnaires. Villagers hunted small mammals mainly by dogs for cultural and ornamental reasons. Products of African savannah hare (Lepus microtis), …


Century-Long Warming Trends In The Upper Water Column Of Lake Tanganyika, Benjamin Kraemer, Simon Hook, Timo Huttula, Pekka Kotilainen, Catherine M. O'Reilly, Anu Peltonen, Pierre-Denis Plisnier, Jouko Sarvala, Rashid Tamatamah, Yvonne Vadeboncoeur, Bernhard Wehrli, Peter B. Mcintyre Jul 2015

Century-Long Warming Trends In The Upper Water Column Of Lake Tanganyika, Benjamin Kraemer, Simon Hook, Timo Huttula, Pekka Kotilainen, Catherine M. O'Reilly, Anu Peltonen, Pierre-Denis Plisnier, Jouko Sarvala, Rashid Tamatamah, Yvonne Vadeboncoeur, Bernhard Wehrli, Peter B. Mcintyre

Biological Sciences Faculty Publications

Lake Tanganyika, the deepest and most voluminous lake in Africa, has warmed over the last century in response to climate change. Separate analyses of surface warming rates estimated from in situ instruments, satellites, and a paleolimnological temperature proxy (TEX86) disagree, leaving uncertainty about the thermal sensitivity of Lake Tanganyika to climate change. Here, we use a comprehensive database of in situ temperature data from the top 100 meters of the water column that span the lake’s seasonal range and lateral extent to demonstrate that long-term temperature trends in Lake Tanganyika depend strongly on depth, season, and latitude. The observed spatiotemporal …


Morphometry And Average Temperature Affect Lake Stratification Responses To Climate Change, Benjamin Kraemer, Orlane Anneville, Sudeep Chandra, Margaret Dix, Esko Kuusisto, David M. Livingstone, Alon Rimmer, S. Geoffrey Schladow, Eugene Silow, Lewis M. Sitoki, Rashid Tamatamah, Yvonne Vadeboncoeur, Peter B. Mcintyre Jun 2015

Morphometry And Average Temperature Affect Lake Stratification Responses To Climate Change, Benjamin Kraemer, Orlane Anneville, Sudeep Chandra, Margaret Dix, Esko Kuusisto, David M. Livingstone, Alon Rimmer, S. Geoffrey Schladow, Eugene Silow, Lewis M. Sitoki, Rashid Tamatamah, Yvonne Vadeboncoeur, Peter B. Mcintyre

Biological Sciences Faculty Publications

Climate change is affecting lake stratification with consequences for water quality and the benefits that lakes provide to society. Here we use long-term temperature data (1970–2010) from 26 lakes around the world to show that climate change has altered lake stratification globally and that the magnitudes of lake stratification changes are primarily controlled by lake morphometry (mean depth, surface area, and volume) and mean lake temperature. Deep lakes and lakes with high average temperatures have experienced the largest changes in lake stratification even though their surface temperatures tend to be warming more slowly. These results confirm that the nonlinear relationship …


Spatial Patterns Of Zooplankton Distribution And Abundance In Relation To Phytoplankton, Fish Catch And Some Water Quality Parameters At Shirati Bay, Lake Victoria-Tanzania, Revania K. Waya, Samwel M. Limbu, Godfrey W. Ngupula, Chacha J. Mwita, Yunus D. Mgaya Nov 2014

Spatial Patterns Of Zooplankton Distribution And Abundance In Relation To Phytoplankton, Fish Catch And Some Water Quality Parameters At Shirati Bay, Lake Victoria-Tanzania, Revania K. Waya, Samwel M. Limbu, Godfrey W. Ngupula, Chacha J. Mwita, Yunus D. Mgaya

Tanzania Journal of Science

Spatial patterns and abundance of zooplankton in aquatic habitats are important determinants for production of fish species, invertebrates and availability of phytoplankton. Weekly monitoring for zooplankton abundance was conducted in Shirati Bay, Lake Victoria, to explore their spatial patterns in relation to phytoplankton, fish catch and some water quality parameters. The vertical distribution of zooplankton was generally higher close to the bottom as compared to surface waters of the lake. Zooplankton vertical distribution positively correlated with water transparency (r = 0.680, p = 0.011). The horizontal abundance of zooplankton was not significantly different amongst the three stations (p = 0.5143). …


Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha Nov 2014

Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha

Tanzania Journal of Science

This study analyzed variability in body shapes among the small Barbus species of the family Cyprinidae currently occurring in the Malagarasi and Pangani River basins years after uplift of the east African topology. Fish specimens were collected from Songati, Muumbara and Nyamagoma within the Malagarasi River basin; Hale and Pangani fall located on Pangani River. It was found that although the landmarks were placed at the same anatomical regions, significant body shapes variations existed. The relative warps analysis for Barbus trimaculatus and Barbus jacksonii populations from Malagarasi and Pangani wetlands revealed intra-locality variations as for populations from other African countries. …


Formation Of Cell Masses In The Myelencephalon Of The Clawed Frog, Xenopus Muelleri, Flora Stephano Jul 2013

Formation Of Cell Masses In The Myelencephalon Of The Clawed Frog, Xenopus Muelleri, Flora Stephano

Tanzania Journal of Science

An important process in the organization of developing nervous system is the clustering of neurons with similar properties to form nuclei. The development of myelencephalon of Xenopus muelleri, a pipid frog that retains a lateral line system throughout life, was studied in Nissl stained serial sections. The results showed that density of neurons increases as the animal develops. Cell masses were formed in the latter half of larval stages (stage 48 to 59). Large neurons migrate first before small neurons. Raphes and reticular formation nuclei and Mauthner cells were the earliest neurons that could be distinctly recognized on the ventral …


Antimycobacterial And Cytotoxicity Evaluation Of The Constituents Of Monodora Carolinae, Nyangi Magori, Stephen S Nyandoro, Joan Je Munissi, Matthias Heydenreich Jul 2013

Antimycobacterial And Cytotoxicity Evaluation Of The Constituents Of Monodora Carolinae, Nyangi Magori, Stephen S Nyandoro, Joan Je Munissi, Matthias Heydenreich

Tanzania Journal of Science

Phytochemical investigation of the stem bark of the recently described species Monodora carolinae (Annonaceae) afforded prenylindole derivatives (E)-4-(1H-indol-6-yl)-but-3-en-2-one (1), 5-formylindole (2), fatty acid (Z)-hexade-7-enoic acid (3) and the lignanamide cannabisin B (4). The structures of the isolated compounds were established using NMR and MS analyses. The antimycobacterial activities of the extracts and isolated compounds were evaluated against Mycobacterium madagascariense (MM) and M. indicus pranii (MIP) using the two-fold microtitre dilution method. While the extracts exhibited minimum inhibitory concentration (MIC) ranging from 500 – 1000 µg/mL, the isolated compounds were 125 – 250 µg/mL, indicating very low activity. Cytotoxic effects were …


Current Status And Future Perspectives Of Bioinformatics In Tanzania, Sylvester L. Lyantagaye Jul 2013

Current Status And Future Perspectives Of Bioinformatics In Tanzania, Sylvester L. Lyantagaye

Tanzania Journal of Science

The main bottleneck in advancing genomics in present times is the lack of expertise in using bioinformatics tools and approaches for data mining in raw DNA sequences generated by modern high throughput technologies such as next generation sequencing. Although bioinformatics has been making major progress and contributing to the development in the rest of the world, it has still not yet fully integrated the tertiary education and research sector in Tanzania. This review aims to introduce a summary of recent achievements, trends and success stories of application of bioinformatics in biotechnology. The applications of bioinformatics in the fields such as …


Species Boundaries And Biogeography Of East African Torrent Frogs Of The Genus Petropedetes (Amphibia: Anura: Petropeditidae), Simon P. Loader, F. Sara Ceccarelli, Mark Wilkinson, Michele Menegon, Jean Mariaux, Rafael O. De Sá, Et Al. May 2013

Species Boundaries And Biogeography Of East African Torrent Frogs Of The Genus Petropedetes (Amphibia: Anura: Petropeditidae), Simon P. Loader, F. Sara Ceccarelli, Mark Wilkinson, Michele Menegon, Jean Mariaux, Rafael O. De Sá, Et Al.

Biology Faculty Publications

Based on morphology there are currently three described East African species of torrent frogs belonging to the tropical African genus Petropedetes (P. dutoiti, P. martiennseni and P. yakusini). Taxonomic uncertainties are evident within this group: a putative new species reported from the Nguru Mountains and the species P. yakusini have a fragmented distribution across the Southern Tanzanian highlands. We conducted a molecular systematic study, sampling populations of East African petropedetids occurring in the mountains of Tanzania (P. martiennseni and P. yakusini), to investigate species boundaries and biogeography. Data provide evidence for the recognition of …


Sinularia Leptoclados (Ehrenberg, 1834) (Cnidaria: Octocorallia) Re-Examined, Catherine S. Mcfadden, Leen P. Van Ofwegen, Yehuda Benayahu Jan 2013

Sinularia Leptoclados (Ehrenberg, 1834) (Cnidaria: Octocorallia) Re-Examined, Catherine S. Mcfadden, Leen P. Van Ofwegen, Yehuda Benayahu

All HMC Faculty Publications and Research

Sinularia leptoclados (Ehrenberg, 1834) is re-described. Sinularia leptoclados var. gonatodes Kolonko, 1926 is synonymized with S. maxima Verseveldt, 1977. Two new species of Sinularia with digitiform lobules, leptoclados-type surface clubs and unbranched interior spindles, are described. An updated maximum likelihood tree of Sinularia species with leptoclados-type clubs (clade 5C) based on two mitochondrial genes (mtMutS, COI) and a nuclear gene (28S rDNA) is presented.


Molecularly Imprinted Polymer Technology: A Powerful, Generic, Facile And Cost Effective Alternative For Enantio-Recognition And Separation: A Glance At Advances And Applications, Jyn Philip, Dms Mosha Dec 2012

Molecularly Imprinted Polymer Technology: A Powerful, Generic, Facile And Cost Effective Alternative For Enantio-Recognition And Separation: A Glance At Advances And Applications, Jyn Philip, Dms Mosha

Tanzania Journal of Science

The emerging Molecularly Imprinted Polymer (MIP) technology has yielded proof of concept, harnessing nature’s fundamentals to yield recognition receptor mimics from the miniaturized basics, borrowing on the ground rules, but conveniently avoiding the complexity, fragility, instability, costs and ethics of animal based bio-affinity matrices. Thus, the impact of bio-sciences on the future of technology is not via direct use of the molecules, but rather the lessons learned. Molecular imprinting is a powerful specialty representing the generic, cost effective and facile alternative for preparation of synthetic custom-tailored receptors. It achieves this via creation of specific selective recognition sites for a pre-determined …


New Glucopyranosylglyceryl-N-Octenyl Adipate And Bioactivity Of Retro And Condensed Chalcones From Toussaintia Orientalis, Ss Nyandoro, Mhh , Nkunya, Cc Josepha, Jo Odalo, I Sattler Dec 2012

New Glucopyranosylglyceryl-N-Octenyl Adipate And Bioactivity Of Retro And Condensed Chalcones From Toussaintia Orientalis, Ss Nyandoro, Mhh , Nkunya, Cc Josepha, Jo Odalo, I Sattler

Tanzania Journal of Science

1-(3-β-D-Glucopyranosylglycer-2-yl)-6-N-(oct-2-enyl)-adipate, [orientalin, 1] was isolated as a new metabolite from the polar leaf extracts of Toussaintia orientalis Verdc (Annonaceae), together with the glycoflavonoids afzelin and quercitrin, and the indolidinoids toussaintines A-C. The reversed chalcones 2-hydroxy-3,4,6-trimethoxychalcone (2) and 2-hydroxy-3,4,6- trimethoxydihydrochalcone (3), the condensed chalcone (+)-6a,12a-dihydro-6-phenyl-7-styryl- 6H,7H-[1]benzopyrano[4,3-][l]benzopyran (4), and mixtures of known triterpenoids and steroids were isolated from the less polar extracts of the root and stem bark of the same plant. The structures were established upon detailed analysis of spectroscopic data and other physical parameters. The chalcones exhibited antimicrobial, anti-inflammatory, antiproliferative and cytotoxic activity at varying efficacy levels, the reversed chalcone …


Composition Of Non Volatile Oils And Antimicrobial Activities Of Extracts From Monanthotaxis Discolor, And An Undescribed Uvariondedron Species, Ds Parmena, Ca Mgina, Cc Joseph Dec 2012

Composition Of Non Volatile Oils And Antimicrobial Activities Of Extracts From Monanthotaxis Discolor, And An Undescribed Uvariondedron Species, Ds Parmena, Ca Mgina, Cc Joseph

Tanzania Journal of Science

The chemical compositions of non volatile oil extracts from two Annoneceous plant species Monanthotaxis discolor and an undescribed Uvariodendron species which are endemic to Eastern Arc Mountains, Tanzania were determined by GC-MS. The biological activities of extracts and fractionated samples were also determined. Both methanol and dichloromethane extracts of the root bark of M. discolor showed mild antimicrobial activity and had positive brine shrimp test (BST). The BST test for dichloromethane extract of M. discolor root bark were LC50 41.794 μg/ml and that of methanol extract showed LC50 13.560 μg/ml. The petroleum ether and dichloromethane extracts of root bark of …


Activity Of Enzyme Trypsin Immobilized Onto Macroporous Poly(Epoxy-Acrylamide) Cryogel, W Johnson, Ymm Makame Dec 2012

Activity Of Enzyme Trypsin Immobilized Onto Macroporous Poly(Epoxy-Acrylamide) Cryogel, W Johnson, Ymm Makame

Tanzania Journal of Science

Bovine pancreatic trypsin has been covalently immobilized onto monolithic polyacrylamide cryogels with epoxy functionality (Epoxy-MPAAGs). The covalent immobilization of trypsin onto Epoxy-MPAAGs was achieved through incorporation of ethylenediamine-glutaraldehyde spacers on the cryogels’ surfaces. The immobilization yield and the influence of pH and temperature conditions on the activity of the immobilized trypsin were assessed by using the hydrolysis of a low molecular weight substrate, N-α-benzoyl-D, L-arginine-p-nitroanilide (BAPNA). Optimal pH and temperature values of 9 and 50 °C, respectively, were established for both the immobilized trypsin and the free trypsin. Activity measurements from the native trypsin before immobilization and the residual free …


Electrochemical Behaviour Of Environmentally Friendly Inhibitor Of Aloe Secundiflora Extract In Corrosion Control Of Carbon Steel In Soft Water Media, J Mutasingwa, J Buchweishaija, Jeg Mdoe Dec 2012

Electrochemical Behaviour Of Environmentally Friendly Inhibitor Of Aloe Secundiflora Extract In Corrosion Control Of Carbon Steel In Soft Water Media, J Mutasingwa, J Buchweishaija, Jeg Mdoe

Tanzania Journal of Science

Electrochemical behaviour of Aloe secundiflora on carbon steel corrosion control in neutral and aerated soft water solutions have been investigated using electrochemical impedance spectroscopy and Tafel polarization techniques. The investigation was performed at different inhibitor concentrations under static and dynamic conditions using a Rotating Disk Electrode (RDE). The impedance and polarization results revealed that A. Secundiflora could be a potential corrosion inhibitor for carbon steel undergoing corrosion in fresh water medium. It was found that Aloe secundiflora reduces the electrochemical processes taking place on carbon steel undergoing corrosion. The inhibitor efficiency increases with increase in A. Secundiflora concentration and gradually …


Correlation Between Morphological, Optical And Electrical Properties Of Zno:Al/Zno Double Layers And The Cu(In,Ga)Se2 Solar Cell Efficiencies, Pd Nsimama Jul 2012

Correlation Between Morphological, Optical And Electrical Properties Of Zno:Al/Zno Double Layers And The Cu(In,Ga)Se2 Solar Cell Efficiencies, Pd Nsimama

Tanzania Journal of Science

The morphological, optical and electrical properties of magnetron sputtered ZnO:Al/ZnO double layers are reported and their correlations with their respective Cu(In,Ga)Se2 (CIGS) solar cell efficiencies are presented. The ZnO:Al/ZnO double layers were produced by using the established baseline RF process and plasma emission monitoring (PEM) DC reactive sputtering. The scanning electron microscope (SEM) and atomic force microscope (AFM) were employed for the surface morphological measurements. The charge carrier concentrations, mobilities and AC resistivities were deduced from Drude’s model. The DC resistivities were determined from the four-point probe measurements. Transmittance and reflectance measurements were done by using the UV-VIS-NIR Lambda 900 …


Sex-Specific Habitat Use And Responses To Fragmentation In An Endemic Chameleon Fauna, Philip Shirk Jul 2012

Sex-Specific Habitat Use And Responses To Fragmentation In An Endemic Chameleon Fauna, Philip Shirk

Theses and Dissertations

Chameleons are an understudied taxon facing many threats, including collection for the international pet trade and habitat loss and fragmentation. A recent field study reports a highly female-biased sex ratio in the Eastern Arc Endemic Usambara three horned chameleon, Trioceros deremensis, a large, sexually dimorphic species. This species is collected for the pet trade, and local collectors report males bring a higher price because only this sex has horns. Thus, sex ratios may vary due to differential rates of survival or harvesting. Alternatively, they may simply appear to be skewed if differences in habitat use biases detection of the sexes. …


Human-Wildlife Interaction In Serengeti And Ngorongoro Districts Of Tanzania: A Case Study On Small Mammals, Fj Magige Mar 2012

Human-Wildlife Interaction In Serengeti And Ngorongoro Districts Of Tanzania: A Case Study On Small Mammals, Fj Magige

Tanzania Journal of Science

In the Serengeti and Ngorongoro Districts, small mammals are said to provide protein and income to the local people. However, they are simultaneously reported to conflict with farming activities. These conflicting aspects have not been investigated there. The present article considers humansmall mammal interactions in six villages adjacent to the protected areas. Data were obtained through questionnaire administration to the local people in the districts. Small mammals were hunted in the two districts for food purposes and some villagers declared that they were earning income from selling small mammals products. Seventy percent of the respondents in Serengeti District claimed that …


The Influence Of Aliphatic Side Chain Of Anacardic Acid On Molecular Recognition Properties Of Imprinted Polymers, Jyn Philip, J Buchweishaija, Ll Mkayula, L Ye Mar 2012

The Influence Of Aliphatic Side Chain Of Anacardic Acid On Molecular Recognition Properties Of Imprinted Polymers, Jyn Philip, J Buchweishaija, Ll Mkayula, L Ye

Tanzania Journal of Science

The objective of this work was to determine the influence of the aliphatic side chain of anacardic acid on molecular recognition properties of imprinted polymers made from anacardanyl methacrylate (AnMcr). Salicylic methacrylate (SaMcr), a structural analog of AnMcr, was synthesized and used as a functional monomer to prepare imprinted polymers for comparison with AnMcr-based polymers. Using divinylbenzene (DVB) as a cross linker and racemic propranolol as a model template, irregular monolithic particles of poly(SaMcr-co-DVB)m were synthesized in toluene, and spherical beads of poly(SaMcr-co-DVB)b and poly(AnMcr-co-DVB)b weresynthesized in acetonitrile by precipitation polymerization. Although imprinted irregular monolithic particles, poly(SaMcr-co-DVB)m, tested in toluene …


Landsat Remote Sensing Data As An Alternative Approach For Geological Mapping In Tanzania: A Case Study In The Rungwe Volcanic Province, South-Western Tanzania, E. E. Mshiu Dec 2011

Landsat Remote Sensing Data As An Alternative Approach For Geological Mapping In Tanzania: A Case Study In The Rungwe Volcanic Province, South-Western Tanzania, E. E. Mshiu

Tanzania Journal of Science

Rungwe Volcanic Province (RVP) is mostly covered by extrusive rocks that overlain the Precambrian basement. The use of Landsat data in this area has revealed the need of effective use of these data in geological mapping programs in Tanzania. Landsat band ratios 5/1, 3/7, 5/7 and 5/4 as well as R: G: B composite images 7:4:1, 7:5:4, 1/3:5/7:3/5 and 4/5:6/7:4/6 played an important role in identifying different rock types in the study area. Ratio images managed clearly to distinguish between mafic and felsic rocks whereby two lithological blocks were identified, Block 1 covers a combination of intrusive and metamorphic rocks …


Growth Performance, Yields And Economic Benefits Of Nile Tilapia Oreochromis Niloticus And Kales Brassica Oleracea Cultured Under Vegetable-Fish Culture Integration, A. P. Shoko, A. Getabu, G. Mwayuli, Y. D. Mgaya Dec 2011

Growth Performance, Yields And Economic Benefits Of Nile Tilapia Oreochromis Niloticus And Kales Brassica Oleracea Cultured Under Vegetable-Fish Culture Integration, A. P. Shoko, A. Getabu, G. Mwayuli, Y. D. Mgaya

Tanzania Journal of Science

An experiment was conducted for 210 days to demonstrate the role of vegetable-fish culture integration in the growth, yields and economic benefits of fish and vegetables. Two 200 m2 earthen fishponds were stocked with Nile tilapia Oreochromis niloticus at 20,000 fish fingerlings per hectare. Pond A was fertilized with chicken manure and stocked fish fed on 35% crude protein supplementary diet referred to here as treated fish pond (TFP). Another fish pond was not fertilized and the fish stocked in it did not receive any supplementary diet referred to here as non treated fish pond (NTFP). Twelve vegetable plots of …


Variability In Parasites’ Community Structure And Composition In Cat Fish With Respect To Level Of Pollution In Mwanza Gulf, Lake Victoria, Tanzania, C. J. Mwita Dec 2011

Variability In Parasites’ Community Structure And Composition In Cat Fish With Respect To Level Of Pollution In Mwanza Gulf, Lake Victoria, Tanzania, C. J. Mwita

Tanzania Journal of Science

This study investigated the composition and structure of the parasite communities in Cat fish with respect to levels of water pollution in Lake Victoria. A total of 1071 Clarias gariepinus with mean TL range of 19 to 27 cm were analyzed from three localities in Mwanza Gulf (Kirumba, 298 fish infected with 15 parasite species), Nyegezi (376 fish, with 15 parasites species) and Malimbe (397 fish, with 16 parasites species). Trematodes and nematodes dominated the population with six (35.3%) and five (29.4%) species, respectively. Mean species richness and heteroxenous/monoxenous ratio showed significant changes (Fr = 8.000; p = 0.0046), being …


Host-Parasites Relationship For Lake Victoria Clariid Fishes And Their Parasite Fauna, C. J. Mwita Dec 2011

Host-Parasites Relationship For Lake Victoria Clariid Fishes And Their Parasite Fauna, C. J. Mwita

Tanzania Journal of Science

Host-parasite co-evolutionary relationships for the clariid fish species of the Lake Victoria basin and their parasite fauna was inferred by cytochrome b gene and the 18S rDNA using ‘a strict coevolutionary’ constrained tree method, the results of which revealed a phylogenetic incongruence between the fish hosts and their parasite fauna. The present study further indicated that the sympatric association between the clariid hosts and non-clariid fishes in Lake Victoria makes it possible for the parasites to switch from one host to another and hence the large number of shared parasites observed. The specificity of some of the parasites, e.g. Diplostomum …