Numerical Simulation of Solids Conveying in Grooved Feed Sections of Single Screw Extruders

For plastic processing extruders with grooved feed sections, the design of the feed section by means of analytical calculation models can be useful to reduce experimental costs. However, these models include assumptions and simplifications that can significantly decrease the prediction accuracy of the throughput due to complex flow behavior. In this paper, the accuracy of analytical modeling for calculating the throughput in a grooved barrel extruder is verified based on a statistical design of experiments. A special focus is placed on the assumptions made in the analytics of a backpressure-independent throughput, the assumption of a block flow and the differentiation of the solids conveying into different conveying cases. Simulative throughput tests with numerical simulation software using the discrete element method, as well as experimental throughput tests, serve as a benchmark. Overall, the analytical modeling already shows a very good calculation accuracy. Nevertheless, there are some outliers that lead to larger deviations in the throughput. The model predominantly overestimates the throughputs, whereby the origin of these deviations is often in the conveying angle calculation. Therefore, a regression-based correction factor for calculating the conveying angle is developed and implemented.

Strongly Regular Graphs

Strongly regular graphs lie at the intersection of statistical design, group theory, finite geometry, information and coding theory, and extremal combinatorics. This monograph collects all the major known results together for the first time in book form, creating an invaluable text that researchers in algebraic combinatorics and related areas will refer to for years to come. The book covers the theory of strongly regular graphs, polar graphs, rank 3 graphs associated to buildings and Fischer groups, cyclotomic graphs, two-weight codes and graphs related to combinatorial configurations such as Latin squares, quasi-symmetric designs and spherical designs. It gives the complete classification of rank 3 graphs, including some new constructions. More than 100 graphs are treated individually. Some unified and streamlined proofs are featured, along with original material including a new approach to the (affine) half spin graphs of rank 5 hyperbolic polar spaces.

Process Evaluation of Recombinant Chitin Deacetylase Expression in E. Coli Rosetta pLysS Cells using Statistical Design of Experiments

Chitin is a natural polymer with N-acetylglucosamine units, extracted from seafood waste as a major source. It remains an underexplored polymer due to its crystalline structure. The commercial applicability can be improved if we could make it soluble. One of the routes employed to decrease this crystallinity is the conversion of chitin to chitosan via deacetylation. The industrial production of chitosan uses chemical methods, which leaves the process footprint on the environment. The greener alternative approach to producing chitosan is using chitin deacetylases (CDA). The enzymatically converted chitosan with known characteristics has a wide range of applications, importantly in the biomedical field. In the present paper, we report heterologous expression of CDA from a marine moneran; Bacillus aryabhattai B8W22. The process and the nutritional conditions were optimized for the submerged fermentation condition of E. coli Rosetta pLysS expressing the recombinant CDA using the design of experiment tools. The employment of central composite design (CCD) resulted in a ~2.39 fold increase in the total activity of expressed CDA with the process conditions of induction temperature at 22 ºC, agitation at 120 rpm, and 30 h of fermentation. The nutritional conditions required for the optimized expression were 0.061% glucose concentration and 1% lactose in media. The employment of these optimal growth conditions could result in cost-effective large-scale production of the lesser-explored moneran deacetylase, embarking on the greener route to produce biomedical grade chitosan.

Use of homeopathy Arnica montana for the issuance of the roots Rosmarinus officinalis L. and Lippia alba (Mill) N.E.Br.

The objective of this work was to evaluate the influence of homeopathic preparation Arnica montana in rooting of Rosemary (Rosmarinus officinalis) and White Lippia (Lippia alba). The cuttings Rosmarinus officinalis and Lippia alba, collected from the medicinal garden at NCA / UFMG, were placed in trays to root with commercial substrate type "plantmax" and immediately after were subjected to daily applications of homeopathic preparations of Arnica montana in dilutions 3cH, 6cH, 9cH, 12cH, with 2 controls, distilled water and ethanol 70%. The statistical design was completely randomized (DIC), with 6 treatments and 4 repetitions, each experimental unit was formed by 10 stakes. After 45 days, were assessed the number of roots, the nummber of shoots, the length of the largest root, the percentage of rooted stakes and the quality of stakes. Arnica montana in dilutions 3cH, 6cH and 12cH stimulated all variables related to the issuance of roots in the species under study, which emphasizes the similarity between Arnica montana and the picture elicited by the physiological process of cutting, promoting an increase in the percentage and quality of the roots. Keywords: Homeopathy; rooting; cutting; Arnica Montana.  Uso do preparado homeopático Arnica montana na formação de raízes de Rosmarinus officinalis L. e Lippia alba (Mill)N.E.E.Br Resumo O objetivo deste trabalho foi avaliar a influéncia do preparado homeopático Arnica montana na formação de raízes de alecrim (Rosmarinus officinalis) e cidreira (Lippia alba). Mudas de Rosmarinus officinalis e Lippia alba, cultivadas no horto medicinal de NCA/UFMG foram colocadas para enraizar em bandejas contendo substrato comercial de tipo "plantamax" e imediatamente após, submetidas a aplicações diárias de preparados homeopáticos de Arnica montana nas diluições 3cH, 6cH, 9cH e 12cH, com dois controles, água destilada e etanol 70%. O desenho estatístico foi completamente randomizado (DIC), com 6 tratamentos e 4 repetições, cada unidade experimental esteve composta de 10 estacas. Depois de 45 dias, foram avaliados o número de raízes, o número de brotos, a longitude da raiz mais longa, porcentagem de estacas enraizadas e qualidade das estacas. Arnica montana nas diluições 3cH, 6cH e 12cH promoveu todas as variáveis relacionadas com a formação de raízes sob estudo, acentuando a semelhança entre Arnica montana e o quadro induzido pelo processo fisiológico do estacamento, promovendo aumento na porcentagem e qualidade das raízes. Palavras-chave: Homeopatia; enraizamento; corte; Arnica Montana.  Uso del preparado homeopático Arnica montana en la formación de raíces de Rosmarinus officinalis L. y Lippia alba (Mill) N.E.Br. Resumen El objetivo de este trabajo fue evaluar la influencia del preparado homeopático Arnica montana en la formación de raíces de romero (Rosmarinus officnalis) y lippia blanca (Lippia alba). Mudas de Rosmarinus officinalis y Lippia alba, cultivados en la huerta medicinal de NCA/UFMG fueron colocadas para arraigar en bandejas conteniendo sustrato comercial de tipo "plantamax" e inmediatamente después fueron sometidas a aplicaciones diarias de preparados homeopáticos de Arnica montana en las diluciones 3cH, 6cH, 9cH y 12cH, con dos controles, agua destilada y etanol 70%. El diseño estatístico fue completamente randomizado (DIC), con 6 tratamientos y 4 repeticiones, cada unidad experimental compuesta por 10 estacas. Después de 45 días, fueron evaluados el número de raíces, número de brotes, longitud de la raíz más larga, porcentaje de estacas arraigadas y la calidad de las estacas. Arnica montana en las diluciones 3cH, 6cH y 12cH promovió todas las variables relacionadas a la formación de raíces en estudio, acentuando la similaridad entre Arnica montana y el cuadro inducido por el proceso fisiológico de estacamiento, promoviendo aumento del porcentaje y calidad de las raíces. Palabras-clave: Homeopatía; enraizamiento; corte; Árnica Montana.  Correspondence author: Filipe Pereira Giardini Bonfim, email: [email protected] How to cite this article: Bonfim FPG, Martins ER, Dores RGR, Barbosa CKR, Casali VWD, Honório ICG. Use of homeopathic Arnica montana for the issuance of roots of Rosmarinus officinalis L. and Lippia alba (Mill) N.E.Br. Int J High Dilution Res [online]. 2008 [cited YYYY Mmm DD]: 7(23); 113-117. Available from: http://journal.giri-society.org/index.php/ijhdr/article/view/276/348. ÂÂÂ

Germination and vigor of lettuce seeds (Lactuca sativa L.) pelleted with homeopathic preparations Alumina and Calcarea carbonica subjected to toxic levels of aluminum.

Background: aluminum toxicity is the most important factor limiting the growth of plants in acid soils, whereas current treatments are unfeasible. For this reason, alternatives are sought for, among which homeopathic treatment. Aims: this study aimed at evaluating the influence of homeopathic preparations Alumina 6cH, Alumina 12cH, Calcarea carbonica 6cH and Calcarea carbonica 12cH on the germination and vigor of lettuce seeds subjected to toxic levels of aluminum in paper-solution. At the same time, it was sought to develop a new procedure to apply homeopathic preparations in plants (pelleting). Methods: the statistical design was entirely randomized (CRD) with 6 treatments and 4 repetitions. Treatments included: 1) pelleted seeds/talc + Alum 6 cH; 2) pelleted seeds/talc + Alum 12cH; 3) pelleted seed/talc + Calc 6cH; 4) pelleted seeds/talc + Calc 12cH; 5) pelleted seeds/talc + distilled water; 6) non pelleted seeds (control). Variables evaluated were: germination percentage (GP), germination speed index (GSI) and radicle length (RL). Results: there was significant difference in GSI and RL – variables that reflect the vigor of seeds - between the samples treated with homeopathic preparations and the controls Conclusions: homeopathic preparations Alumina 6cH and 12cH and Calcarea carbonica 6cH and 12cH had significant effect on the vigor of lettuce seeds subjected to stress conditions.

Application of mathematical probabilistic statistical model of base – FFCA financial data processing

In order to improve the detection and filtering ability for financial data, a data-filtering method based on mathematical probability statistical model, a descriptive statistical analysis model of big data filtering, probability density characteristic statistical design data filtering analysis combined with fuzzy mathematical reasoning, regression analysis according to probability density of financial data distribution, and threshold test and threshold judgment are conducted to realize data filtering. The test results show that the big data filtering and the reliability and convergence of the mathematical model are optimal.

Clever Experimental Designs: Shortcuts for Better iPSC Differentiation

For practical use of pluripotent stem cells (PSCs) for disease modelling, drug screening, and regenerative medicine, the cell differentiation process needs to be properly refined to generate end products with consistent and high quality. To construct and optimize a robust cell-induction process, a myriad of cell culture conditions should be considered. In contrast to inefficient brute-force screening, statistical design of experiments (DOE) approaches, such as factorial design, orthogonal array design, response surface methodology (RSM), definitive screening design (DSD), and mixture design, enable efficient and strategic screening of conditions in smaller experimental runs through multifactorial screening and/or quantitative modeling. Although DOE has become routinely utilized in the bioengineering and pharmaceutical fields, the imminent need of more detailed cell-lineage specification, complex organoid construction, and a stable supply of qualified cell-derived material requires expedition of DOE utilization in stem cell bioprocessing. This review summarizes DOE-based cell culture optimizations of PSCs, mesenchymal stem cells (MSCs), hematopoietic stem cells (HSCs), and Chinese hamster ovary (CHO) cells, which guide effective research and development of PSC-derived materials for academic and industrial applications.

Maintaining Integrity of Worldwide FINGER Clinical Trials During the COVID-19 Pandemic

The COVID-19 pandemic presents challenges to the conduct of randomized clinical trials of lifestyle interventions. World-Wide FINGERS international network convened a forum for researchers to discuss statistical design and analysis issues they faced during the pandemic. We report experiences of three trials that, at various stages of conduct, altered designs and analysis plans to navigate these issues. We provide recommendations for future trials to consider as they develop and launch behavioral intervention trials. The pandemic led researchers to change recruitment plans, interrupt timelines for assessments and intervention delivery, and move to remote intervention and assessments protocols. The necessity of these changes add emphasis to the importance, in study design and analysis, of intention to treat approaches, flexibility, within site stratification, interim power projections, and sensitivity analyses. Robust approaches to study design and analysis are critical to negotiate issues related to the intervention.