Effective use of evolutionary computation to parameterise an epidemiological model

Predictive epidemiological models are able to be used most effectively when they have first been shown to fit historical data. Finding the right parameters settings for a model is complex: the system is likely to be noisy, the data points may be sparse, and there may be many inter-related parameters. We apply computational intelligence and data mining techniques in novel ways to investigate this significant problem. We construct an original computational model of human papilloma virus and cervical intraepithelial neoplasia with the ultimate aim of predicting the outcomes of varying control techniques (e.g. vaccination, screening, treatment, quarantine). Two computational intelligence techniques (genetic algorithms and particle swarm optimisation) are used over one- stage and two-stage optimisations for eight real-valued model parameters. Rigorous comparison over a variety of quantitative measures demonstrates the explorative nature of the genetic algorithm (useful in this parameter space to support the modeller). Correlations between parameters are drawn out that might otherwise be missed. Clustering highlights the uniformity of the best genetic algorithm results. Prediction of gender-neutral vaccination with the tuned model suggests elimination of the virus across vaccinated and cross-protected strains, supporting recent Scottish government policy. This preliminary study lays the foundation for more widespread use of computational intelligence techniques in epidemiological modelling

The self-reference effect in dementia: Differential involvement of cortical midline structures in Alzheimer’s disease and behavioural-variant frontotemporal dementia

Encoding information in reference to the self enhances subsequent memory for the source of this information. In healthy adults, self-referential processing has been proposed to be mediated by the cortical midline structures (CMS), with functional differentiation between anterior-ventral, anterior-dorsal and posterior regions. While both Alzheimer’s disease (AD) and behavioural-variant frontotemporal dementia (bvFTD) patients show source memory impairment, it remains unclear whether they show a typical memory advantage for self-referenced materials. We also sought to identify the neural correlates of this so-called ‘self-reference effect’ (SRE) in these patient groups. The SRE paradigm was tested in AD (n=16) and bvFTD (n=22) patients and age-matched healthy controls (n=17). In this task, participants studied pictures of common objects paired with one of two background scenes (sources) under self-reference or other-reference encoding instructions, followed by an item and source recognition memory test. Voxel-based morphometry was used to investigate correlations between SRE measures and regions of grey matter atrophy in the CMS. The behavioural results indicated that self-referential encoding did not ameliorate the significant source memory impairments in AD and bvFTD patients. Furthermore, the reduced benefit of self-referential relative to other-referential encoding was not related to general episodic memory deficits. Our imaging findings revealed that reductions in the SRE were associated with atrophy in the anterior-dorsal CMS across both patient groups, with additional involvement of the posterior CMS in AD and anterior-ventral CMS in bvFTD. These findings suggest that although the SRE is comparably reduced in AD and bvFTD, this arises due to impairments in different subcomponents of self-referential processing

Comparison of Four Different Preparation Methods for Making Injectable Microgels for Tissue Engineering and Cell Therapy

Purpose One of the major challenges in cell-laden microgel bioprocessing is to design an effective method of cell encapsulation in the biomaterial carrier while retaining high cell viability and ensuring small enough particles for injectability. In this study we aim to compare four bioprocessing techniques for making hydrogel microcarriers, including by emulsification gelation and dropwise gelation approaches. Methods A Pluronic-Fibrinogen (FF-127) hydrogel biomaterial was used to make the microgels based on a lower critical solubility temperature (LSCT) phase transition. Additional cross-linking of the hydrogels was achieved using light-activated photochemistry (i.e., photopolymerization). The four bioprocessing methodologies include emulsification gelation in oil (with and without dual photo-initiator free-radical polymerization), reverse thermal gelation (in warm cell culture media), dropwise gelation through a vibrating needle device, and dropwise gelation through an atomization device (in warm cell culture media gelation baths). The microgels made with each method were characterized with and without cells; comparisons of microgel size and cell growth were reported. Results The dual photo-initiator emulsification technique produced FF-127 spherical microgels with an average diameter of 222 and 256 mu m, with and without cells, respectively. The reverse thermal encapsulation produced irregularly shaped microgels with an average diameter of 241 and 702 mu m, with and without cells, respectively. The vibrating needle and atomization techniques produced irregularly shaped microgels with an average diameter of 195 and 151 mu m without cells, respectively, and 464 and 332 mu m with cells, respectively. The viability of fibroblasts in the microgels was high after 24 h, except for those treatments that underwent photo-polymerization (i.e., emulsification photo-polymerization and vibrating needle with photo-polymerization). The cells remained viable for up to 3 weeks in culture and spread three-dimensionally in the microgels over this time course. Conclusions The rapid temperature-induced phase transition of the FF-127 enables the formation of microgels either through dropwise gelation or by emulsification, both through physical cross-linking. The use of a free-radical polymerization cross-linking reaction was more cyto-toxic to the cells as compared to the physical cross-linking by reverse thermal gelation alone. The average microgel size in all the techniques was significantly smaller and more uniform when producing the microgels without cells as compared to with cells. The reverse thermal gelation technique produced cell-laden microgels with the least amount of specialized equipment and bioprocessing steps of all the methods reported. Lay Summary This study provides the framework for producing cell-laden microgels that are of a sufficiently small diameter to be used for injectable cell therapy. The challenge in this regard is to design a simple, scalable, and efficient methods of cell encapsulation in the biomaterials, retaining high cell viability and ensuring small enough particles for injectability. For this purpose, we evaluated four methods that are commonly applied in microgel bioprocessing, and tested these with two types of cells using hydrogels that exhibit lower critical solubility temperature (LCST) properties. This investigation has enabled us to identify advantages and disadvantages for each system of bioprocessing of cell-laden microgels

PEMBUATAN KOLOM DESINFEKSI BAKTERI E. COLI. DAN DEGRADASI POLUTAN ORGANIK DENGAN FOTOKATALISIS TiO2

Indonesia merupakan salah satu negara dengan jumlah penduduk terbesar di dunia. Sekarang ini pada nomor urut ke – 4 setelah Cina, India dan USA . Dengan demikian jumlah penduduk semakin besar kebutuhan akan air bersih serta layak minum juga sangat besar. Kondisi mengakibatkan potensi bisnis dalam penyediaan air layak minum juga sangat pesat perkembangannya. Mahasiswa sebagai salah satu aset bangsa yang nantinya setelah lulus tentunya akan terjun ke masyarakat, mengabdikan ilmunya baik sebagai pekerja pada instansi pemerintah maupun. Swasta. Akan lebih mereka bisa menciptakan lapangan kerja sendiri dengan berwira swasta mengamalkan ilmu yang mereka peroleh. Oleh sebab itu perlu dibangkitkan jiwa kewirausahaan para mahasiswa, melalui mata kuliah-mata kuliah yang diambil mereka selama di bangku kuliah oleh sebab itu pada mata kuliah kimia anorganik II ini disisipkan materi yang diharapkan bisa membangkitkan jiwa kewirausahaan itu yaitu dengan memanfaatkan sifat semikonduktor TiO2 dalam desinfeksi E. Cofi dan degradasi polutan senyawa organik pada air minum. Kegiatan ini bertujuan untuk menghasilkan sebuah modul IBA yang dapat digunakan untuk memberikan rangsangan dari ide untuk berwira usaha bagi mahasiswa sehingga kelak jika mereka sulit memperoleh pekerjaan atau untuk membuat usaha sampingan selain pekerjaan utama mereka, dapat digunakan. Disamping itu, kegiatan ini juga bertujuan untuk menghasilkan sebuah bahan ajar yang dapat dipergunakan oleh mahasiswa. Dengan adanya bahan ajar ini, diharapkan mahasiswa akan lebih mudah dalam memahami materi yang di berikan