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A continuous process flowsheet for biodiesel production from crude castor oil and methanol was developed on Aspen HYSYS™ simulation environment. It consists of an acid-catalysed sub-process for pre-treatment of the crude feedstock and a base-catalysed one for trans-esterification of treated oil. Reactions involved were defined using kinetic parameters obtained from lab-scale experiments for increased realism, and reactor setup was decided based on basic technological and economical assessments. Specifications of other unit operations and flows were obtained from different approximation methods, literature adaptation and trade-off consideration. Input and output quality controls were achieved via simple adjustments with tight tolerances. The use of crude feedstock reduced the cost of raw material while expanding the scale of the process, which managed to produce 8000 tons of biodiesel having purity of over 99 % a year. Specifically, the process could remove up to 90.83 % amount of free fatty acids in the crude oil and convert up to 93.82 % of oil to biodiesel. [ABSTRACT FROM AUTHOR]

Deep brain stimulation is an effective neurosurgical intervention for movement disorders such as Parkinson's disease. Despite its success, the underlying mechanisms are still debated. One tool to better understand them is the Volume of Tissue Activated (VTA), that estimates the region activated by electrical stimulation. Different estimation approaches exist, these typically assume isotropic tissue properties and modelling of anisotropy is often lacking.The present work was aimed at developing and testing a method for patient-specific VTA estimation that incorporated an anisotropic conduction model. Our method was implemented within the open-source toolbox Lead-DBS and is accessible to the public.The present method was further tested with two patient cases and compared to a standard Lead-DBS pipeline for VTA estimation. This showed encouraging similarities in one test scenario and expected differences in another test scenario. Further validation with a wider cohort is warranted.

k -Oligocarrageenan (OC) is an effective biostimulator and a protector against disease infections for plants. However, the effect of OC molecular weight (MW) on plant growth is not fully understood. In this work, OCs with three different MWs (42, 17 and 4 kDa) was prepared by varying the degradation reaction time using ascorbic acid as a reagent. The product structure was confirmed by Fourier-transform infrared spectroscopy (FTIR) data. The growth promotion for maize ( Zea mays L.) plants was investigated by foliar spray application of the prepared OCs. Field trials were carried out in two years, 2018 and 2019. The results showed that among treatments, OC with 4 kDa exhibited the best performance in both crop growth and grain yield parameters which indicated increases compared to the control in plant height (6.9-19.9%), length of ears (12.2%), diameter of ears (9.1%), fresh grain weight (17.8%), dry grain weight (20.0%) and grain yield (21.3%). Moreover, low MW OC augmented NP uptake in the plant growth while no effect on K uptake was observed. Therefore, OC with low MWs is potentially promising to apply as a promoter to enhance yield of crops.

Objective: Patients with bilateral vestibulopathy (BV) can still have residual "natural" function. This might interact with "artificial" vestibular implant input (VI-input). When fluctuating, it could lead to vertigo attacks. Main objective was to investigate how "artificial" VI-input is integrated with residual "natural" input by the central vestibular system. This, to explore (1) whether misalignment in the response of "artificial" VI-input is sufficiently counteracted by well-aligned residual "natural" input and (2) whether "artificial" VI-input is able to influence and counteract the response to residual "natural" input, to show feasibility of a "vestibular pacemaker.", Materials and Methods: Five vestibular electrodes in four BV patients implanted with a VI were available. This involved electrodes with a predominantly horizontal response and electrodes with a predominantly vertical response. Responses to predominantly horizontal residual "natural" input and predominantly horizontal and vertical "artificial" VI-input were separately measured first. Then, inputs were combined in conditions where both would hypothetically collaborate or counteract. In each condition, subjects were subjected to 60 cycles of sinusoidal stimulation presented at 1 Hz. Gain, asymmetry, phase and angle of eye responses were calculated. Signal averaging was performed., Results: Combining residual "natural" input and "artificial" VI-input resulted in an interaction in which characteristics of the resulting eye movement responses could significantly differ from those observed when responses were measured for each input separately ( p  < 0.0013). In the total eye response, inputs with a stronger vector magnitude seemed to have stronger weights than inputs with a lower vector magnitude, in a non-linear combination. Misalignment in the response of "artificial" VI-input was not sufficiently counteracted by well-aligned residual "natural" input. "Artificial" VI-input was able to significantly influence and counteract the response to residual "natural" input., Conclusion: In the acute phase of VI-activation, residual "natural" input and "artificial" VI-input interact to generate eye movement responses in a non-linear fashion. This implies that different stimulation paradigms and more complex signal processing strategies will be required unless the brain is able to optimally combine both sources of information after adaptation during chronic use. Next to this, these findings could pave the way for using the VI as "vestibular pacemaker."

Collagen-based biomaterials are currently used as cell culture scaffolds in tissue engineering approaches. These materials are being developed with increased functional complexity, such as the incorporation of glycosaminoglycans. Our study shows the impact of heparin intercalation at specific binding sites in telopeptide-free collagen fibrils in terms of their structure, mechanics, and cell response. We demonstrate that heparin binds specifically and in a competitive manner along the tropocollagen helix at places that are occupied in vivo by telopeptides in fibrillar collagen type I. On the basis of this finding, we elucidate the reason for the in vivo dogma that heparin does not intercalate in fibrillar collagens. We further reveal the direct relationship among structure, mechanics, and function in terms of the effect of incorporation of intercalated heparin on the fibrillar structure, fibrillar bending modulus and flexural rigidity and the dynamic response of adherent cells to collagen scaffolds. This tight relationship is considered particularly important when designing xenogeneic scaffolds based on natural collagen type I to trigger cell proliferation and differentiation., (Copyright © 2011 Elsevier Ltd. All rights reserved.)