Littérature scientifique sur le sujet « Studio BIOREVE »

Eight groups of cellulose amorphous region models in which the mass fraction of water was separately 0%, 1%, 2%, 3%, 4%, 5%, 6%, and 7% were established using a molecular dynamics software material studio. The PCFF force field was selected to simulate the molecular dynamics of the model under the constant-pressure and constant-temperature (NPT) ensemble. The simulated temperature was set to 433.15 K. The experiment showed that the hydrogen bonds between cellulose chains affected the structure of cellulose, which led to the change of the end-to-end distance of the cellulose chain and the overall size of a cell. The diffusion degree of water molecules was closely related to the number of hydrogen bonds between cellulose and water. In the process of heat treatment of bamboo, the present simulation results suggest that the structure of bamboo may be damaged when the mass fraction of water vapor reaches or exceeds 7%.

A formaldehyde-cellulose amorphous region model at the micro-level was established using the molecular dynamics software Materials Studio to simulate the change of cellulose and formaldehyde molecules in an external temperature field. The diffusion coefficients of formaldehyde molecules increased as the temperature increased. Moreover, the total number of hydrogen bonds decreased, and the interaction energy in the formaldehyde-cellulose model was reduced, which confirmed this conclusion and indicated that temperature increase could enhance the diffusion of formaldehyde in cellulose. The mechanical parameters of cellulose were analyzed in terms of Young’s modulus, shear modulus, bulk modulus, Poisson’s ratio, and the ratio of bulk modulus to shear modulus (K/G), which were affected by the temperature. The elastic modulus (E, G, and K) of cellulose decreased as the temperature increased, while the Poisson’s ratio V and K/G values increased. The results of the research explain how elevated temperature can promote the release of formaldehyde in furniture from a microscopic perspective, which supports each other with the results of previous experimental data and practical applications in production.

Using the molecular dynamics software Materials Studio, a micro-level carbon dioxide – cellulose model was established to study the supercritical carbon dioxide drying of eucalyptus wood. The change of the primary components of the eucalyptus wood cellulose were also studied, by simulating various pressures, i.e., 10, 15, 20, 25, and 30 Pa, and simulating a temperature of 323 K. Results showed that the diffusion coefficient of carbon dioxide decreases as the pressure increases, and it reaches the maximum at 20 Pa, which was confirmed by the number of hydrogen bonds in the carbon dioxide cellulose model. Combined with the comprehensive analysis of the mechanical parameters, the Poisson’s ratio γ and the ratio of bulk modulus to shear modulus (K/G) values of cellulose first increased and then decreased as the pressure increased, and the Young’s modulus increased as the pressure increased. From a microscopic point of view, the study shows that eucalyptus cellulose has good mechanical properties when dried by supercritical carbon dioxide under a pressure of 20 Pa. The simulation results of the dynamic model agreed well with the measured results, and the simulation results support the previous experimental data and the practical application results in production.

In a simulation model of the process of corn straw crushing, its physical parameters and the model itself influence the accuracy of the numerical calculations of the discrete element method. This study attempts to improve the simulation accuracy of the crushing process and to find the optimal combination of parameters. Based on the Hertz-Mindlin with Bonding contact model, multiple particle replacement and bonding programs written using Visual Studio were imported through the application programming interface (API) of a discrete element method (DEM) model to establish three particle-bonding materials for a numerical simulation of the crushing process. Using results of mechanical corn stalk tests, DEM simulations of impact fracture, compression fracture, and bending fracture were conducted to determine the optimal combination of parameters. The resultant DEM-parameter combination led to simulation errors of 3.83%, 5.95%, and 7.86% in numerical simulations of impact fracture, bending fracture, and compression fracture of corn stalks, respectively. The performance of the corn stalk DEM using the proposed optimal parameter combination was validated using a 9RS-60 corn stalk crusher, revealing that the numerical simulation error was 8.77%. This study can improve the accuracy of the discrete element method in the simulation of the corn straw breaking process.

Characteristics of patients with Ankylosing Spondylitis, Rheumatoid and Psoriatic Arthritis in treatment with biologics in Verona’s cohort: results from Veneto’s Region Biologics Register ( BIOREVE STUDY). Background: Since 2013, in Veneto’s Region, data registration is mandatory for all patients affected by Rheumatoid arthritis (RA), Psoriatic Arthritis (PA), Ankylosing Spondylitis (AS) in treatment with biologic agents. The biologic DMARDs currently marketed in Italy are: anti-TNF (originator and biosimilar infliximab, etanercept, adalimumab, certolizumab and golimumab), anti-IL6 (tocilizumab), anti-CD20 (rituximab), CTLA-4 like (abatacept) and anti IL-12/23 (ustekinumab). Objectives: The aim of this study was first to describe the characteristics of patients with RA, PA, AS under biologics and then, to extract and analyze real-life data regarding rheumatic treatments in Verona’s cohort. Methods: The study has been carried out on behalf of Regione del Veneto, Giunta regionale- Ricerca Sanitaria Finalizzata-Venezia-Italy. Data used for analysis were retrieved from Veneto’s Region Biologics Register (VRBR). VRBR provides that core variables such as onset and type of disease, anthropometric characteristics (age, sex, body weight, height) are registered at the beginning. Furthermore, prior and concomitant rheumatic treatment (conventional and biologic DMARDs, corticosteroids, NSAIDs), disease activity indicators (DAS 28-PCR, ASDAS-PCR, pain-NRS), prognostic factors (positivity for rheumatoid factor and/ or anti-citrulline antibodies in AR, presence of radiological erosions) were assembled at baseline, every 6 months and at the time of biologic’s switch or swap. Results: A total of 983 patients under biologics were examined; 543 (55,2 %) with AR, 272 (27,7% ) with AP and 168 (17,1%). Between these, 262 ( 27,2%) patients were naïve to biologics, 128 with AR, 84 with AP, 50 with SA. Mean duration of disease was of 15,3, 10,7 and 12,6 years respectively for RA, PA and AS. Radiological erosions were present in 73% of RA-patients and the percentage was higher in those with positivity for rheumatoid factor and/ or anti-citrulline antibodies ( 84,4% versus 56,2%). More than half of the patients in this cohort were treated at least with one biologic agent; anti-TNFs were the main biologic used (RA:54,8%, PA:92,7%, AS: 100%) followed by Abatacept ( 25,4%), tocilizumab ( 12,3%) and rituximab ( 5,9%) in patients with RA. Methotrexate (MTX) was the prevalent associated c-DMARDs ( 41,8% in RA and 34,2% in PA) with mean dose of 11,9 mg/week in RA and 12,1 mg/week in PA. The optimal dose of methotrexate was not achieved prevalently because of drug intolerance. Conclusions: Profile of both conventional and biological DMARDs looks very different according to the type of rheumatic disease. The first data show an underuse of MTX in patients with RA and PA under biologics with a low mean dosage due to intolerance. Next step is to evaluate long-term outcomes in clinical practice.

Autolysis or tryptic hydrolysis converts β-thrombin (α-T) t β-thrombin ( β -T), and subsequently β-T to y-thrombin (γ-T). Human β-T differs from native α-T by the loss of a unique ll-re-sidues peptide arising from the B chain. Unlike its bovine counterpart, human β-Tisa transient intermediate and its enzymatic properties had not yet been investigated using purified materiaL After 3 min incubation of human β-T with trypsin-sepharose, the resulting β-T was separated from α- and γ-T by chromatography on Biorex 70 with a gradient from 10 mM to 500 mM phosphate at pH 8. No major differences were found between human α- and β-T regarding the kinetic parameters (Km, kcat, kcat/Km) on S 2238, nor the rate of inactivation by TLCK. In contrast, inhibition of β-T by DFP was slower (k = 426 ±[; 10.8 M-1 min−1) compared to α-T (764.5 ± 19.5 M−11min−1and the inhibition constant for benzami-dine was higher with β-T (Ki = 11.2 ± x00B1;.2 10−4 M) compared to α-T (Ki = 2.86± 0,06 10−4 M). The drastic reduction in the clotting activity of β-T (25 u mg−1 versus 3000 u mg−1 for α-T) was further explored by measuring the affinity of β-T for fibrinogen and fibrin. Human fibrinogen was used as a competitor in the inactivation of thrombin by DFP : 10 μM fibrinogen prevented the inhibition of α-T by DFP but failed to modify the inactivation rate of α-T. Binding of thrombin to fibrin was studied using fibrin monomers covalently linked to sepharose 4B, equilibrated in 50mM Tris, pH 7.5, 50 mM NaCl : β -T did not bind to the resin, whereas α-T was retained and eluted upon application of a NaCl gradient.In conclusion, the loss of the peptide extending from lie (63) to Arg (73) in the thrombin B chain is responsiblefor multiple defects in thrombin enzymatic activity. Although, the three active site residues Ser (205), His (43), Asp (99) remain in an active configuration, subtle changes are induced in the microenvironment of the catalytic Ser (205), and in particular, in the primary binding pocket. In addition, the results presented in this study indicate thatthe loss of clotting activity is mainly the result of a decreased affinity for fibrinogen and fibrin, suggesting that the structural changesaffect both the fibrinopeptide groove and the anionic binding site involved in fibrinogen/fibrin recognition.