Application of joined local models in the technical diagnostics

Współczesna diagnostyka techniczna stosująca model boryka się często ze zbyt dużym stopniem złożoności stosowanych modeli. Rozwiązania tego problemu, najczęściej stosowane dotychczas, polegały na upraszczaniu niektórych zależności modelu bądź świadomym pomijaniu niektórych wejść obiektu celem uproszczenia struktury modelu. W referacie przedstawiono odmienne podejście polegające na stosowaniu zbioru stosunkowo prostych modeli lokalnych w miejsce jednego złożonego modelu globalnego. Taki zbiór modeli lokalnych nazywany jest wielomodelem.Nowadays technical diagnostics that applies a model struggles very often with a high-complexity degree of applying model. Solutions of that problem, applied most frequent so far, consisted in simplifying of some model relations or conscious omitting of some object inputs with the purpose of making a model structure simpler. In the paper, it is presented inflected approach that consists in application of a set of simply local models instead one complex global model. Such a set of local models is called multi-model

Rhinoceros Serum MicroRNAs

MiRNA sequences and counts in serum of four species of rhinoceros: black (Diceros bicornis), greater one-horned (Rhinoceros unicornis), Sumatran (Dicerorhinus sumatrensis) and white (Ceratotherium simum). Serum samples from black and Sumatran rhinos were from individuals categorized as healthy, unhealthy (afflicted with disease other than iron overload), and afflicted with iron overload disorder. Serum samples from greater one-horned and white rhinos were from healthy individuals.RT-qPCR Raw Cq values for serum miRNAs are also included for additional samples collected from black and Sumatran rhinos.This excel file contains four tabs: miRNA sequencing sample info and data and miRNA sample info and PCR data. A few of the samples overlap between the datasets - refer to assigned sample number and animal ID to identify overlaps.Version 2: PCR data was added to fileVersion 3: Sequencing files and PCR files were combined into one excel file for ease of use and additional sample demographic info was added.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Physico-chemical kinetic modelling of hydrolysis of a steam-explosion pre-treated corn stover A two-step approach

A physico-chemical kinetic model for the hydrolysis of pre-treated corn stover is proposed. This model takes into account two reactions in series, the hydrolysis of cellulose to cellobiose and the production of glucose from cellobiose. Experiments have been carried out with an industrial enzymatic cocktail from Trichoderma reesei containing endo and exoglucanases and a very low activity of β-glucosidase. Kinetic parameters were calculated by fitting the proposed model to experimental data of cellulose and glucose concentrations with time. The kinetic parameters fulfilled all relevant statistical and physical criteria. The kinetic model has been validated with published saccharification data regarding differently pre-treated corn stover and enzymatic cocktail, in this case with a very high β-glucosidase activity (as it is common in modern industrial cellulase cocktails). In both cases, the kinetic model proposed could be fitted very appropriately to cellulose hydrolysis data

Enzymatic hydrolysis of several pretreated lignocellulosic biomasses: Fractal kinetic modelling

9 Pág.Enzymatic hydrolysis of three pre-treated lignocellulosic biomasses -LCB- (wheat straw-WS-, corn stover-CSV- and cardoon stems -CS-) is studied. These biomasses were pre-treated by two methods: diluted sulfuric acid and acid ethanol-water extraction at six severity levels (H values). Pretreated solid fractions were hydrolyzed with commercial enzyme cocktails at standard conditions. A first-order kinetic fractal model was fitted to the experimental results. This model accurately describes the hydrolysis of all biomasses at all pre-treatment conditions studied. The results show that the formal first-order kinetic constant k depends on the biomass nature. The hydrolysis rate increases as the pre-treatment severity does, while the fractal exponent value h decreases. With these pre-treatments, and in terms of k and h, WS is highly reactive and, at medium H with EW pretreatment, highly accessible; CSV has a low reactivity and high accessibility and CS has the lowest reactivity and an increasing accessibility as severity rises.The authors want to thank Spanish Ministry of Economy and Competitivity (MINECO) for funding this study under Project CTQ2017-84963-C2, and Madrid Regional Government for funding via Project RETOPROSOST P2013-MAE2907, and Chilean National Commission of Scientific and Technological Research (CONICYT) for funding PV post-doctoral grant via a grant “Doctorado Becas Chile/2015” with reference 72160108.Peer reviewe

Wheat straw fractionation by ethanol-water mixture Optimization of operating conditions and comparison with diluted sulfuric acid pre-treatment

The fractionation of wheat straw by ethanol-water (EW) pre-treatment was studied regarding its main operating conditions: time, temperature, L/S ratio and ethanol percentage were optimized by using an orthogonal experimental design (Taguchi). Afterwards, diluted sulfuric acid (DSA) hydrolysis and EW treatments have been compared in terms of energy consumption and yield of a cellulosic solid residue able to be enzymatically hydrolyzed to glucose. Experimental results show that temperature is the only variable of EW with a significant effect on the quality of the pretreated solids. EW pre-treatment of wheat straw is more effective than DSA hydrolysis due to its higher capacity of delignification. Moreover, a high glucose yield (80%) can be obtained by enzymatic hydrolysis of a solid pretreated with a moderate energy input EW (160 °C, 45 min) while wheat straw needs of a higher energy input during DSA to produce a similar yield of glucose after saccharification

Study of the enzymatic activity inhibition on the saccharification of acid pretreated corn stover

The inhibition of the enzymatic saccharification of acid pretreated corn stover (PCS) biomass due to several compounds either present in PCS or produced during saccharification has been studied. The prospective inhibitors tested were glucose (≤110 g L-1), celobiose (≤24 g L-1), xylose (≤50 g L-1), arabinose (≤1.5 g L-1), furfural (≤2 g L-1), hydroxymethylfurfural (≤1 g L-1), acetic acid (≤4 g L-1), and lignin (≤50 g L-1). Each of these compounds was added at three different concentrations, being the concentration intervals different according to standard maximum concentrations of such compounds in the reaction medium, previously measured and described in literature. In addition, these experiments were employed to evaluate the standard error present during the evaluation of the results obtained in the inhibition reactions. Those results show that significant inhibition was only detected for lignin (more than 25 g L-1) and it was also appreciable for glucose at high concentrations (above 75 g L-1), although it was not remarkable at medium concentrations (40 g L-1). On the other hand, neither of the remaining compounds tested presented any significant inhibitory effect at the usual process concentration range

Influence of fluid dynamic conditions on enzymatic hydrolysis of lignocellulosic biomass Effect of mass transfer rate

The effect of fluid dynamic conditions on enzymatic hydrolysis of acid pretreated corn stover (PCS) has been assessed. Runs were performed in stirred tanks at several stirrer speed values, under typical conditions of temperature (50 °C), pH (4.8) and solid charge (20% w/w). A complex mixture of cellulases, xylanases and mannanases was employed for PCS saccharification. At low stirring speeds (<150 rpm), estimated mass transfer coefficients and rates, when compared to chemical hydrolysis rates, lead to results that clearly show low mass transfer rates, being this phenomenon the controlling step of the overall process rate. However, for stirrer speed from 300 rpm upwards, the overall process rate is controlled by hydrolysis reactions. The ratio between mass transfer and overall chemical reaction rates changes with time depending on the conditions of each run. © 2016 Elsevier Ltd

Enzymatic saccharification of acid pretreated corn stover Empirical and fractal kinetic modelling

Enzymatic hydrolysis of corn stover was studied at agitation speeds from 50 to 500 rpm in a stirred tank bioreactor, at high solid concentrations (20% w/w dry solid/suspension), 50 °C and 15.5 mgprotein·gglucane −1. Two empirical kinetic models have been fitted to empirical data, namely a potential model and a fractal one. For the former case, the global order dramatically decreases from 13 to 2 as agitation speed increases, suggesting an increment in the access of enzymes to cellulose in terms of chemisorption followed by hydrolysis. For its part, the fractal kinetic model fits better to data, showing its kinetic constant a constant augmentation with increasing agitation speed up to a constant value at 250 rpm and above, when mass transfer limitations are overcome. In contrast, the fractal exponent decreases with rising agitation speed till circa 0.19, suggesting higher accessibility of enzymes to the substrate. © 2016 Elsevier Lt

Kinetic modeling of cellobiose by a β-glucosidase from Aspergillus fumigatus

The final step in lignocellulose enzymatic saccharification is the cellobiose conversion toglucose by β-glucosidases (BG). In this work, a valid kinetic model to describe cellobiosedegradation for an industrial mixture of BG enzymes present in Aspergillus fumigatus isselected. Firstly, the enzyme mixture was characterised in terms of protein content andenzymatic activity on p-NPG (1326 U mLpreparation−1), determining the molecular weight ofthe only BG activity band observed in zymograms by SDS-PAGE and MALDI-TOF: 94 kDa.Subsequently, to select the correct kinetic model for the enzymatic hydrolysis of cellobiose,a combined strategy was performed: Firstly, non-linear regressions were applied to initialhydrolysis rate data for different enzyme concentrations and initial substrate and productconcentrations, observing inhibition by cellobiose and glucose. Secondly, the optimal kineticmodel was discriminated by a coupled non-linear regression-DOE numerical integrationapproach, by fitting several possible kinetic models involving different product inhibitionmechanisms to progress curve data from runs at various initial substrate concentrationsand temperatures. The best kinetic model involves non-competitive substrate inhibitionand product competitive inhibition with two binding sites for glucose