Development Of Modified Biopolymer Adsorbents From Natural Polysaccharides For Renewal Of Abattoir Wastewater

DissertationThe wastewater effluents produced by poultry and the red meat industries were analysed in the quest to detect the presence of heavy metals in abattoir wastewater and to establish and optimize alternative methods of purifying wastewater from Bloemfontein abattoirs in an effort to reduce water pollution. Water samples were randomly collected from two categories of local abattoirs in Bloemfontein, namely poultry and red meat abattoirs. The samples were found to contain high levels of alkali and alkaline earth metals (Ca, Mg, K and Na) at rates above 100 mg/ℓ. Other elements present in the wastewater samples that were analyzed included Cr, Ni, Cu and Pb, which are elements that have been reported to cause devastating effects in animals and the environment. Analyses of the Cr, Ni, Cu and Pb using ICP-OES showed the presence of ultra-trace levels (0.05 – 0.2 mg/ℓ) in both wastewater solutions. These elements confirmed the presence of heavy metals in the water bodies at the abattoirs. A chromatographic technique using different chitosan products as adsorbents was developed. Some cross-linked chitosan products were synthesized from different chitin (mussel, prawn, pang and silver) products. The modified chitosan products were obtained from cross-linking the chitin with glutaraldehyde, formaldehyde, epichlorohydrine, maleic anhydride, p-benzoquinone, poly (ethylene) glycol diglycidyl ether (PEG diglycidyl ether), 1-vinyl-2-pyrrolidone, 1,3-dichloroaceone, acrylic acid and s-methyl-benzylamine. Characterization of these cross-linked chitosan products was performed using FTIR, SEM and viscometer assessments. The results obtained from the analyses using SEM spectroscopy revealed that the different products had different morphological structures. The results of the analyses showed significant adsorption rates of alkali and alkaline earth metals (Ca, Mg, K and Na) using shrimp chitosan that was cross-linked with maleic anhydride (J1) and shrimp chitosan that was cross-linked with acrylic acid (I2) chitosan products. The shrimp and crab chitosan starch that was cross-linked with formaldehyde (C1 and C2) was also shown to effectively adsorb the alkali and alkaline earth metals present in the waste samples. Lower concentrations of heavy metals were recovered (0.05 - 0.2 mg/ℓ) for Cr, Ni, Cu and Pb using these chitosan products. Although no complete adsorption of these elements was achieved in both the wastewater samples, the results showed a substantial improvement of the water eluted which demonstrated the effectiveness of the method using synthesized chitosan products

Modification of Novel Chitosan-Starch Cross-Linked Derivatives Polymers: Synthesis and Characterization

Published ArticleThis paper reports on the synthesis and characterization of cross-linked chitosan products prepared from using crab, shrimp beads and ten different cross-linked polymers which includes; glutaraldehyde, formaldehyde, epichlorohydrine, maleic anhydride, p-benzoquinone, poly (ethylene) glycol diglycidyl ether (PEG diglycidyl ether), 1-vinyl-2-pyrrolidone, 1,3-dichloroaceone, acrylic acid and s-methyl-benzylamine. Characterization of the cross-liked chitosan products was done using Fouriertransform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) to determine the structural morphology and the stretching frequencies of the products. The obtained FTIR stretching frequencies of the cross-linked chitosan products were matched against the starting material and the literature values to confirm the products. SEM analysis showed mixtures of regular and amorphous products. Different percentage yields (crab, 26–98% and shrimp, 30–88%) were obtained for the cross-linked chitosan products depending on the cross-linked polymer used

Assessing the impact of neurosurgery and neuroanatomy simulation using 3D non-cadaveric models amongst selected African medical students

BackgroundLaboratory dissections are essential to acquire practical skills to perform neurosurgical procedures. Despite being traditionally done on cadavers, they are often unavailable and suffer from cultural barriers in the African context. Non-cadaveric UpSurgeOn neurosurgery models have been developed to bridge this barrier, providing an almost similar experience with the human body. This study aimed to assess the impact of the UpSurgeOn hands-on-touch non-cadaver model training amongst selected Cameroon medical students.MethodsAn anonymous 35-item questionnaire was distributed online using Google drive systems to medical students who attended UpSurgeOn's hands-on-touch non-cadaver model training course. These questions aimed to capture data on previous experience with neuroanatomy and neurosurgery practicals and the perception, attitudes, and impact of the UpSurgeOn neurosurgery tool.ResultsEighty-six students completed the survey. The mean age was 21.2 ± 1.868 years, 61.6% were males with 62.8% of respondents being medical students in preclinical years. Before the training, 29.4% had a fair knowledge of neuroanatomy. Textbooks and Youtube videos were the main sources of neuroanatomy and neurosurgery knowledge for more than half of the respondents. Up to 91.5% had no prior exposure to a neuroanatomy/neurosurgery cadaver laboratory dissection, and 22.6% and 17.6% had witnessed and performed at least one craniotomy before, respectively. There were 11.1%, 15.5%, and 31.3% of our respondents who had used a surgical microscope, a neurosurgical instrument, and the UpSurgeOn Neurosurgery tool before, respectively. The majority perceived the UpSurgeOn tool easy to use and felt they needed to learn just a few things before getting going with the box. Most thought of increasing the use of the UpSurgeOn Box and saw the need to be part of the training curriculum. Finally, the majority felt this tool helped to increase familiarity and acquire neurosurgical skills, and to develop the orientation skills needed during neurosurgical approaches.ConclusionUndergraduate exposure to traditional neurosurgery/neuroanatomy labs is limited in Cameroon. Neurosurgery/neuroanatomy practical skills are gained essentially using non-practical means. Most students found the UpSurgeOn tool user-friendly, saw the need to incorporate it as part of their training, and perceived it to be essential in getting acquainted with neurosurgical skills