On the simulation of the Newtonian fluid Extrudate Swell using a moving mesh finite volume interface tracking method

The extrudate swell, the geometrical modifications that take place when the flowing material leaves a confined flow inside a channel and moves freely without the restrictions promoted by the walls, is a relevant phenomenon in several polymer processing techniques. For instance, in profile extrusion, the extrudate cross-section is subjected to a number of distortions motivated by the swell, which are very difficult to anticipate, especially for complex geometries. As happens in many industrial processes, numerical modelling might provide useful information to support design tasks, i.e., to allow identifying the cross section geometry which produces the desired profile, after the changes promoted by the extrudate swell. In this work we study the capability of an open-source moving mesh finite volume interface tracking solver, to simulate the extrudate swell process in profile extrusion. For this purpose, the data provided by Mitsoulis et al. (E. Mitsoulis, G.C. Georgiou, and Z. Kountouriotis. A study of various factors affecting Newtonian extrudate swell. Computers & Fluids, 57:195{207, 2012) on the simulation of the extrudate swell flow of a Newtonian fluid at different Reynolds number, is considered as the reference for validation. The results obtained with the OpenFOAM solver show a very good agreement with the reference data.NORTE-07-0162-FEDER-000086 and the Minho Advanced Computing Center (MACC) for providing HPC. CPCA_A00_6057202

Validation of a moving mesh finite volume interface tracking method through the numerical simulation of the Newtonian extrudate swell

The geometrical modifications that take place when the flowing material leaves a confined flow inside a channel and moves freely without the restrictions promoted by the walls, commonly designated by extrudate swell, is a relevant phenomenon in several polymer processing techniques. For instance, in profile extrusion, the extrudate cross-section is subjected to a number of distortions motivated by the swell, which are very difficult to anticipate, especially for complex geometries. To circumvent those problems numerical modelling might provide useful information to support design tasks, i.e., to allow identifying the cross section geometry which produces the desired profile, after the changes promoted by the extrudate swell. In this work we employed an open-source moving mesh finite volume interface tracking solver to simulate the extrudate swell process in profile extrusion. The data provided by Mitsoulis et al. (E. Mitsoulis, G.C. Georgiou, and Z. Kountouriotis. A study of various factors affecting Newtonian extrudate swell. Computers & Fluids, 57:195{207, 2012) on the simulation of the extrudate swell flow of a Newtonian fluid at different Reynolds number is considered as the reference for validation. The results obtained with the OpenFOAM solver show a very good agreement with the reference dataCPCA_A00_60572020. NORTE-07-0162-FEDER-000086 and the Minho Advanced Computing Center (MACC) for providing HPC resources that contributed to the research results reported within this abstrac

The immediate effects of dry needling for ankle and toe plantar flexors on spasticity and balance in patients with stroke

Background: Spasticity is one of the most important symptoms of stroke, which leads to movement constraints and disability. The presence of spasticity in the ankle and toe plantar flexor muscles disturbs the balance and gait of patients with stroke. Dry needling has been introduced as a new method for the treatment of spasticity. The aim of this study was to investigate the immediate effects of the ankle and toe plantar flexors dry needling on spasticity and balance in patients with stroke. Methods: This study was a clinical pretest-posttest study. Twenty patients with stroke (12 males and 8 females), the mean age of 56.5±13 years were included. The assessments were performed before dry needling, immediately after dry needling and 15 minutes after that. Dry needling was used to treat gastrocnemius (ankle plantar flexor) muscles, flexor digitorum longus, and flexor digitorum brevis of the affected lower limb of the patients, for one session. Each muscle was needled for one minute with fast in-fast out technique. The outcome measures of the study were modified modified Ashworth scale (MMAS) for the assessment of the severity of muscle spasticity, timed up and go test and one leg stance test, for balance evaluation. The study was conducted in neurological physical therapy, Clinic of Rehabilitation School, Tehran University of Medical Sciences in Iran, from April 2017 to April 2018. Results: The results showed a significant decrease in the ankle and toe plantar flexor muscles spasticity both immediately after dry needling and at 15 minutes follow-up (P=0.001). The duration of timed up and go test (P=0.001) and one leg stance test (P=0.001) improved significantly after dry needling and this improvement persisted for 15 minutes after dry needling. The effect size for timed up and go test and one leg stance test was small (Cohen'sd=0.33 and 0.32 respectively). Conclusion: This study suggests that dry needling is effective in improving spasticity of ankle and toe plantar flexor muscles and the balance of patients with stroke. Further research with larger sample size and control group is necessary. © 2020 Tehran University of Medical Sciences. All rights reserved

Homozygous missense WIPI2 variants cause a congenital disorder of autophagy with neurodevelopmental impairments of variable clinical severity and disease course.

WIPI2 is a member of the human WIPI protein family (seven-bladed b-propeller proteins binding phosphatidylinositols, PROPPINs), which play a pivotal role in autophagy and has been implicated in the pathogenesis of several neurological conditions. The homozygous WIPI2 variant c.745G>A; p.(Val249Met) (NM_015610.4) has recently been associated with a neurodevelopmental disorder in a single family. Using exome sequencing and Sanger segregation analysis, here, two novel homozygous WIPI2 variants [c.551T>G; p.(Val184Gly) and c.724C>T; p.(Arg242Trp) (NM_015610.4)] were identified in four individuals of two consanguineous families. Additionally, follow-up clinical data were sought from the previously reported family. Three non-ambulant affected siblings of the first family harbouring the p.(Val184Gly) missense variant presented with microcephaly, profound global developmental delay/intellectual disability, refractory infantile/childhood-onset epilepsy, progressive tetraplegia with joint contractures and dyskinesia. In contrast, the proband of the second family carrying the p.(Arg242Trp) missense variant, similar to the initially reported WIPI2 cases, presented with a milder phenotype, encompassing moderate intellectual disability, speech and visual impairment, autistic features, and an ataxic gait. Brain MR imaging in five patients showed prominent white matter involvement with a global reduction in volume, posterior corpus callosum hypoplasia, abnormal dentate nuclei and hypoplasia of the inferior cerebellar vermis. To investigate the functional impact of these novel WIPI2 variants, we overexpressed both in WIPI2-knockout HEK293A cells. In comparison to wildtype, expression of the Val166Gly WIPI2b mutant resulted in a deficient rescue of LC3 lipidation whereas Arg224Trp mutant increased LC3 lipidation, in line with the previously reported Val231Met variant. These findings support a dysregulation of the early steps of the autophagy pathway. Collectively, our findings provide evidence that biallelic WIPI2 variants cause a neurodevelopmental disorder of variable severity and disease course. Our report expands the clinical spectrum and establishes WIPI2-related disorder as a congenital disorders of autophagy

Hepatitis B virus genotype D is the only genotype circulating in Iranian chronic carriers, the unique pattern of genotypic homogeneity

Aim: To characterize the hepatitis B virus surface protein genotypes and sequence variations among HBsAg positive chronic Iranian patients from different ethnic groups. Method: The surface genes from 312 patients were amplified and directly sequenced. Results: All strains (100) belonged to genotype D and subtypes ayw2. The average nucleotide mutation frequency was 0.91 (dN/dS < 1.0), indicated negative selection. There was no significant correlation between HBV DNA and ALT levels and the occurrence of amino acid substitutions. However, in terms of HBeAg/Anti-HBe status, the association between both groups for silent nucleotide mutation was strong, indicating selection bias on missense mutations. A higher number of amino acid mutations was found in anti-HBe positive versus HBeAg positive patients.Conclusion: The uniqueness pattern of HBV genetics hemogeniety together with the low mutational frequency indicated that HBV has introduced to Iran recently and isolation of people in the absence of intermixing with other genotypes led to a homologous pattern. © 2014 ACT

Palladium Nanoparticles Loaded on Carbon Modified TiO2 Nanobelts for Enhanced Methanol Electrooxidation

Made available based on the terms of the Springer open license. Publication available at Springer via http://dx.doi.org/10.5101/nml.v5i3.p202-212Carbon modified TiO2 nanobelts (TiO2-C) were synthesized using a hydrothermal growth method, as a support material for palladium (Pd) nanoparticles (Pd/TiO2-C) to improve the electrocatalytic performance for methanol electrooxidation by comparison to Pd nanoparticles on bare TiO2 nanobelts (Pd/TiO2) and activated carbon (Pd/AC). Cyclic voltammetry characterization was conducted with respect to saturated calomel electrode (SCE) in an alkaline methanol solution, and the results indicate that the specific activity of Pd/TiO2-C is 2.2 times that of Pd/AC and 1.5 times that of Pd/TiO2. Chronoamperometry results revealed that the TiO2-C support was comparable in stability to activated carbon; but possesses an enhanced current density for methanol oxidation at a potential of -0.2 V vs. SCE. The current study demonstrates the potential of Pd nanoparticle loaded on hierarchical TiO2-C nanobelts for electrocatalytic applications such as fuel cells and batteries.FedDev Ontario through the Applied Research and Commercialization (ARC) InitiativeNatural Sciences and Engineering Research Council of Canada (NSERC) programMicrobonds, Inc

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field