Organogenesis and Somatic Embryogenesis from Scalps of Musa Spp. Cv. Tanduk

This study was carried out to establish reliable and efficient regeneration protocols through organogenesis and somatic embryogenesis from scalps of Musa spp. cv. Tanduk. Scalps are highly proliferated meristems which are ideal materials for organogenesis and embryogenesis in Musa spp. Shoot-tips of Musa spp. Cv. Tanduk were cultred on a modified MS (Murashige and Skoog, 1962) medium containing various concentration of 0, 10, 50 and 100 pM BAP with 1.0 pM IAA added to each BAP concentration. The study showed a reasonably high percentage of scalp formation on MS medium supplemented with 100 pM of BAP and 1.0 pM IAA within 16 to 28 weeks after first culture. BAP at 50 pM produced poor quality scalps and 10 pM BAP resulted in higher proliferation of shoot buds. MS without BAP produced only a single elongated shoot from the cultured shoot tips. Subculture was performed on 4 weeks interval. Histological study was done following subculture of the proliferated shoot tip on 100 pM BAP treatment. Continuous changes were observed starting from a dome-shaped apical meristem covered by layers of leaf primordia to a zone of high division activity. This resulted in the proliferation of meristematic clumps aggregated in a cauliflower-like structure (scalps). The scalps appeared as undulating zone with h o w s separating the hdges of naked tiny meristems. Regeneration of shoots fiom scalps was tested on different concentrations of 1 .O, 2.5 and 5.0 pM BAP incorporated into MS basal medium. Treatment with 2.5 pM BAP produced an average of 40.63 shoots, the highest number of shoot-buds after 8 weeks of culture. The highest mean shoot-bud height attained after 8 weeks was 2.19 cm on 1.0 pM BAP. Shoots obtained from scalps were rooted on half strength and full strength MS media and on MS medium supplemented with 1.0, 5.0 and 10 pM IBA. Full-strength MS medium with 5.0 pM IBA produced the highest number of roots per explant (15.08). Meanwhile, the longest root length (1 1.07 cm) was attained in half strength MS medium. However, there was no significant difference root length observed between half-strength MS, full-strength MS and MS with 1.0 pM IBA. Plantlets produced fiom the scalps through organogenesis were acclimatized under 50% shade in four types of growing medium comprising of sand, peat, sand + top soil + goat dung (3:2: 1 vlv) and top soil + sand (1 : 1 v/v). After six weeks, the highest survivability (77.5%) was obtained in medium consisting of top soil + sand + goat dung. This was followed by 67.5 % survivability in both sand and peat media The lowest survivability (65%) was recorded fiom medium containing a mixture of top soil + sand. Plants acclimatised in medium containing top soil + sand + goat dung were observed to be morphologically the best with very green broad leaves and vigorous sterns. Multiplication of shoots from shoot-tip of banana cv. Tanduk was also investigated. The excised shoot-apices were cultured on MS basal medium supplemented with 0, 5, 10, 15 and 20 1M BAP in combination with 1.5 pM IAA in each. It was observed that BAP concentration over subculture cycles affected the mean number of shoots produced from the shoot tips and the mean shoot height (cm) attained. Shoot formation increased with increase in BAP concentrations and vice versa for shoot height. The highest mean number of shoot-buds (17.47) was produced on 20 pM BAP. The mean number of shoot-buds increased with subsequent subcultures at all levels of BAP tested, reaching the highest mean (27.53) at the 20& week of subculture. The highest mean height (2.43 cm) was obtained on MS medium supplemented with the lowest BAP concentration of 5 pM. Meanwhile, the mean shoot-bud height also increased over subculture cycles, reaching 3.14 cm at the fifth subculture (20 weeks). Two pathways of regeneration via somatic embryogenesis, starting fiom the scalps of Musa spp. cv. Tanduk were also investigated. Scalps were excised and cultured in liquid MS medium supplemented with 5.0 and 10 pM 2,4-D. Scalps placed on 10 pM 2,4-D died because of very high incidence of browning and necrosis. Meristematic globules were released fiom the scalps placed in liquid medium with 5.0 pM 2,4-D. The meristematic globules were either rounded, amoeboid or kidney shaped. Following transfer of the meristematic globules to fi-esh medium of the same composition for cell suspension establishment, yellowish embryogenic cells were formed at the periphery of the meristematic globules- The embryogenic cells were released as single cells into the medium which later gave rise to proembryo-like structures. However, these structures failed to regenerate into plantlets. The embryogenic response of scalps was also investigated on half strength MS semisolid medium containing 2.5, 5.0 and 7.5 pM 2,4-D with 1.0 pM zeatin. The study revealed that 5.0 pM 2,4-D with 1.0 pM zeatin produced the highest percentage of (48 %)embryogenic complexes. Histological sections of the embryogenic complexes induced on scalps of Musa spp. C.V. Tanduk revealed the presence of globular structures, pro-embryos and somatic embryos. Two regeneration media, Ganapathi et al. (1999) medium and CBte et al. (1996) medium were tested for plantlet regeneration fiom the embryogenic complexes. Both regeneration media tested did not exhibit high germination percentages which were 14- 17% on Cote et al. (1996) medium and 2-5% on Ganapathi et al. (1999) medium. Embryogenic cell suspensions were initiated from the scalps-derived embryogenic complex, in half strength MS medium supplemented with 5.0 pM 2,4-D and 1.0 pM zeatin. The study revealed that the embryogenic cell suspensions have high potential towards somatic embryogenesis. Homogeneous embryogenic lines were obtained and matured by plating onto filer paper discs wetted with semi-solid MS medium. The somatic embryos produced were placed on modified MS solid medium containing 0.5, 1.0, and 1.5 pM BAP for germination. The highest germination percentage of 52.60% was attained on medium with 0.5 pM BAP. However, there was no significant difference in the percentage of germination between the treatments. Histological observations on the different stages of somatic embryo development showed bipolar somatic embryos, matured somatic embryos with distinct shoots and root meristems, and two apical meristems originating from the same somatic embryo. Scalps were found to be appropriate in vitro materials for organogenesis and somatic embryogenesis. Somatic embryo regeneration through the establishment of embryogenic cell suspensions from the embryogenic complexes was the best for hture researches

Implementing SexEd programs for persons with disabilities: A Survey of Teachers' Views

The aim was to investigate teachers' views regarding implementing SexEd programs for persons with IDs. Teachers' views regarding implementing SexEd programs for persons with IDs was studied. Teachers must be teaching in special education, both sexes (males and females). Participants were 180 teachers (females, n= 30, 16.6%, and males 150, 83.4%).  No differences were found between the two sexes in their responses towards implementing SexEd programs for persons with IDs. Teacher's age had significant effect on respondents' responses towards implementing SexEd programs for persons with IDs. Old teachers had positive responses towards implementing SexEd programs for persons with IDs.     &nbsp

A conceptual framework for power generation technology management for developing countries.

Most of the current approaches of technology management emphasis on the need of systematic technology management in both strategic and operational perspectives. The majority of developing countries have a problem to manage technology systematically and fail to implement management techniques effectively. There is a big gap between developed and developing countries in most fields of technology and the power generation sector is among them. The goal of this research work is to develop a conceptual framework for power generation technology management for developing countries. Also to draw a systematic guide lines and clear strategy to help decision makers to optimise their decisions to save resources and less harming to climate. In this work, a systematic approach is developed to select a suitable hard technology for power generation technologies selection using the AHP software. A sensitivity analysis is carried out to show how the decision is affected with the change in criteria and sub-criteria. After this objective is achieved, some other soft technologies are identified with their limits and integrated with hard technologies for power generation. A validation of the proposed model is provided using the questionnaire technique

Analysis and implementation of robust numerical methods to solve mathematical models of HIV and Malaria co-infection

Philosophiae Doctor - PhDThere is a growing interest in the dynamics of the co-infection of these two diseases. In this thesis, firstly we focus on studying the effect of a distributed delay representing the incubation period for the malaria parasite in the mosquito vector to possibly reduce the initial transmission and prevalence of malaria. This model can be regarded as a generalization of SEI models (with a class for the latently infected mosquitoes) and SI models with a discrete delay for the incubation period in mosquitoes. We study the possibility of occurrence of backward bifurcation. We then extend these ideas to study a full model of HIV and malaria co-infection. To get further inside into the dynamics of the model, we use the geometric singular perturbation theory to couple the fast and slow models from the full model. Finally, since the governing models are very complex, they cannot be solved analytically and hence we develop and analyze a special class of numerical methods to solve them.South Afric

Prolific plant regeneration through organogenesis from scalps of Musa sp cv. Tanduk

A prolific plant regeneration system using scalps derived from shoot tips of Musaspp. cv. Tanduk was developed. Highly proliferating scalps, produced after four monthly subcultures of shoot tip explant on Murashige and Skoog (MS) medium supplemented with 100 mM BAP and 1.0 mM IAA, were placed on MS basal medium supplemented with 1.0, 2.5 and 5.0 mM BAP. Rooting of shoots was assessed on hormone-free half strength and full strength MS media and on MS medium supplemented with 1.0, 5.0 and 10 mM IBA. Four types of potting media comprising of sand, peat, sand + top soil + goat dung (3:2:1 v/v) and top soil + sand (1:1 v/v) were evaluated during acclimatization of the plantlets. Prolific shoot regeneration from scalps was obtained on MS medium containing 2.5 mM BAP, at 9.61 and 40.6 shoots per explant after 4 and 8 weeks of culture, respectively. Meanwhile, the highest mean shoot height of 2.19 cm was attained on MS medium with 1.0 mM BAP after 8 weeks of culture. Full-strength MS medium supplemented with 5.0 mM IBA produced the highest mean number of roots per explant at 15.08, while the highest mean root length of 11.07 cm was obtained on hormone-free half strength MS medium at week 4 of culture. The highest plant survivability of 77.5% was achieved in potting medium consisting of top soil + sand + goat dung after 6 weeks of acclimatization. The plants were morphologically normal with vigorous stems and broad green leaves

Synthesis of Calcium Nitrate Self-Healing Microcapsules Using Aerosol OT Hexane Solution for Cementitious Materials

Calcium nitrate synthesis of in urea-formaldehyde shell has recently been used to produce self-healing microcapsules for construction applications. The original synthesis was based on water-in-oil emulsion with sulfonic acid as fundamental ingredient of the oil (continuous) phase. It has been modified herein by changing the composition of the continuous (oil) phase by mixing anionic surfactant, Aerosol OT (AOT) with hexane to prepare the solution while keeping the aqueous phase unchanged. The submicron refined calcium nitrate microcapsules. In order to characterize the microcapsules encapsulated using the aforementioned, procedure, a Scanning Electron Microscopy (SEM) was utilized. The obtained microcapsules had satisfactory diameter and shell thickness. To assess the effect of the prepared microcapsules on the compressive and flexural strengths, mortar mixes containing 75% microcapsules (by weight of cement), as an introductory dosage, were made. It has been demonstrated that incorporating the self-healing microcapsules prepared using the procedure suggested in this study did not cause significant reductions in the mortar samples' strengths. Hence, the encapsulation methodology presented here may be utilized to investigate their self-healing efficiency in cementitious materials

Characterization of immune cell infiltrate in tumor stroma and epithelial compartments in oral squamous cell carcinomas of Sudanese patients

Background Tumor immune infiltrate has been explored in oral squamous cell carcinoma (OSCC), but studies on simultaneous characterization of multiple immune cell subtypes separately in stromal and intraepithelial tumor compartments are limited. Objectives We aimed to investigate the immune cell infiltrate in OSCC by using immunohistochemistry (IHC) for a panel of inflammatory cells in stromal and epithelial tumor compartments for a better characterization of the tumors. Methods Thirty-six OSCC lesions and nine normal oral mucosa (NOM) samples from patients attending Khartoum Dental Teaching Hospital, Sudan were investigated for presence of tumor infiltrating lymphocytes, tumor-associated macrophages, tumor-associated neutrophils, and PD-L1 positive cells in the inflammatory infiltrate by single and double IHC. Digital quantitative analysis (Aperio Technologies Inc.) was performed separately for stromal and epithelial compartments. Results OSCC cases displayed a higher inflammatory infiltrate in the associated stroma, but not in the epithelial compartment when compared to NOM. The immunosuppressive type of inflammatory infiltrate, that is, T regulatory cells (FoxP3+ cells) was identified to be significantly higher in the epithelial compartment of tumors with advanced clinical state. An immunoscore developed by combining intraepithelial FoxP3+ and CD4+ cells was found significantly higher in lesions from elderly patients, localized at toombak dipping-related sites, poorly differentiated OSCCs, or with loco-regional lymph node spreading. Conclusions Despite heavy immune cell infiltration in tumor-associated stroma, the majority of OSCCs in this cohort displayed a low intraepithelial immune infiltration. An immunoscore based on combined CD4 and FoxP3 intraepithelial expression may serve as an indicator of advanced tumor progression and should be further investigated for its use as potential prognostic biomarker in OSCC.publishedVersio

Twice-daily insulin glargine for patients with uncontrolled type 2 diabetes mellitus.

Insulin glargine is recombinant human insulin analog that is commonly used in patients with type 2 diabetes as well as those with type 1 diabetes. Pharmacokinetic and pharmacodynamics studies of insulin glargine had shown that it has an onset of action that ranged from 1.2 to 1.8 h while its duration of action is 18 to 26 h. Because of its long duration of action insulin glargine is usually prescribed once daily. However, several reports have shown that the administration of insulin glargine once daily is not enough to achieve adequate glucose control in some patients requiring a twice daily dosing. The first report on using insulin glargine twice daily was published shortly after its availability. It described a patient with type 1 diabetes who had consistently elevated bedtime glucose values on once daily insulin glargine administered in the evening. There was significant improvement in glucose values after changing the frequency of insulin glargine to twice daily as a split dose every 12 h. Albright and colleagues found that twice daily glargine therapy was required in patients with type 1 diabetes who developed morning hypoglycemia and/or afternoon hyperglycemia while on once daily therapy; the twice daily regimen was associated with a significant reduction in HbA1c levels compared to patients who were on once daily therapy