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Agro-wastes such as sugar cane bagasse can be explored for use in different aspects. Its applicability as a source of cellulose has attracted much interests especially in biomedical field among various applications. In the current work chemically purified cellulose (CPC) and cellulose nanocrystals (CNCs) were effectively extracted from sugarcane bagasse (SCB). The cellulose was obtained by chemical treatment of SCB using HNO3, NaOH and a bleaching agent. Nanocrystals were further prepared from the extracted cellulose using H2SO4 hydrolysis followed by washing with deionized water and acetone. The obtained materials were characterized for surface morphological using Fourier transform infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD) analysis. The thermal properties were evaluated using TGA/DTG. The FTIR showed the disappearance of the peaks responsible for the hemicelluloses and lignin. These results were confirmed by TGA which proved gradual elimination of non-cellulosic constituents. X-ray Diffractometer depicted an increase in crystallinity occasioned by sequential treatments to get the cellulose nanocrystals. Cellulose nanocrystals had a spherical shape with a diameter of 38nm as compared to the chemically purified cellulose which had a diameter of 76nm. The CNCs prepared with this method were seen to be less agglomerated and more crystalline thus possess a higher potential as bionanocomposite either for biomedical applications or for wastewater treatment among other industrial application. This approach also provides an opportunity for the sugar companies to effectively manage their waste product.

Purpose Application of Tithonia diversifolia leaves as organic fertilizer is common in most rural regions in Africa. There is usually time period for curing between preparation and application stage. However, this curing period leads to reduction in fertilizer efficiency. This study aimed at analyzing the change in functional groups, particle morphology, size and elemental composition from preparation and application stages of T. diversifolia leaves as organic fertilizer. Method The fertilizer was synthesized from T. diversifolia leaves. The synthesized fertilizer was stored at room temperature and pressure conditions for a grace period of 5 days; as is norm. Characterization of the samples at the two stages was done by FT-IR (functional groups), SEM (morphology), TEM (particle size) and EDS (elemental composition). Results The results indicated reduction or complete loss of amine groups and carboxylic groups over this period. The fertilizer particles agglomerated over the storage period. Particle size increased from 112 nm to 133 nm diameter. There was a significant variation in the elemental composition between preparation and application time of the fertilizer samples. Conclusion These findings prompt for better storage techniques to be used or reduction in curing and storage period of the fertilizers to minimize loss of plant nutrients.

Granule cell activity in cerebellar cortex directly excites Purkinje cells via parallel fibers, but it also inhibits Purkinje cells via cerebellar cortical interneurons. This contribution of inhibitory interneurons to cerebellar cortical processing remains poorly understood. In the present study we examined the response properties of stellate cells in vitro to input patterns that may result from granule cell activity in vivo. We constructed input waveforms that represented the sum of inputs from all individual synapses and applied these waveforms to the soma of stellate cells during whole cell recordings in acute brain slices. The stimulus waveforms contained fluctuations in a broad range of frequencies and were applied at different amplitudes. To determine the contribution of synaptic shunting to stellate cell spike responses we applied the same input waveforms either as a simulated synaptic conductance using dynamic clamping or as a direct current injection stimulus. Only the dynamic clamp stimulus has the shunting properties of real synapses, i.e. leads to different-sized synaptic current as a function of membrane potential. We found that stellate cells spike with millisecond precision in response to fast temporal fluctuations in the total synaptic input. Transient increases in excitatory input frequency led to pronounced stellate cell spike responses, indicating that this pathway may be very responsive to even small assemblies of co-activated granule cells. This was observed regardless of whether the input waveform was applied as a conductance with dynamic clamping, or as a direct current injection. Thus the shunting properties of a conductance input did not play a major role in determining the control of precisely timed spiking. In contrast, a more tonic increase in excitatory conductance did not lead to a sustained spike response as obtained with prolonged positive current injection. However, even with tonic current injection the precision of spiking was lost, as previously observed. Overall, the synaptic response function of stellate cells suggests that this cell type may pick out transients in granule cell activity, and may generate precisely timed inhibition of Purkinje cells during behavior. [Copyright &y& Elsevier]