Modeling particulate complex flows using XFEM

Particulate flows arise in a wide class of research areas and industrial processes, for example, fluidized suspensions, materials separation, rate of mixing enhancement, filled polymers, etc. In many of the applications, the fluid phase displays complex non-Newtonian flow behavior. Adding particles in a complex fluid further complicates the flow behavior. In order to study the particle motion in complex fluids such as viscoelastic fluids, a numerical analysis is an essential requirement due to inherent nonlinear behavior of the fluids. An extended finite element method (XFEM) has been developed for the direct numerical simulation of particulate complex flows. The main advantage of the method is that the movement of particles can be simulated on a fixed Eulerian mesh without any need of remeshing. The proposed method has been applied to various particulate flow problems: • Flow of a viscoelastic fluid around a stationary cylinder The method is verified by comparing the solutions with those of simulations using a boundary-fitted mesh and a fictitious domain method. Our method shows a significant improvement of local accuracy around the rigid body compared to the fictitious domain method, obtaining solutions similar to those of boundary-fitted mesh solutions. • Particle migration in circular Couette flow of a viscoelastic fluid The particle migrates to a stabilized radial position near the outer cylinder regardless of its initial position. As the fluid elasticity increases, the particle migrates more rapidly toward the outer cylinder, and the stabilized radial position of the particle shifts toward the outer cylinder. With increasing the particle size, the particle migrates more rapidly toward the outer cylinder. • Dynamics of particles suspended in two-phase flows A model for the dynamics of particles suspended in two-phase flows is presented by coupling the Cahn-Hilliard theory with the extended finite element method. To demonstrate and validate the technique, the dynamics of a single particle at a fluid-fluid interface is studied. In particular, the effects of interfacial thickness, surface tension, particle size and viscosity ratio of two fluids are investigated. As interfacial thickness increases; surface tension increases; particle size decreases; or viscosity ratio decreases, the particle moves rapidly towards its equilibrium position. The movement of a particle passing through multiple layers of fluids is also presented to demonstrate the wide applicability of the method to problems associated with complex morphology of the fluids

Effect of dietary mugwort (Artemisia vulgaris L.) and pine needle powder (Pinus densiflora) on growth performance, serum cholesterol levels, and meat quality in broilers

The effects of dietary mugwort and pine needle powder supplementation on growth performance, serum cholesterol, and meat quality of broilers were evaluated in a 35 days feed trial. 200 one day old broilers were randomly allocated to five dietary treatments (0, 1 and 2% mugwort or 1 and 2% pine needle powder) with four replicate pens of 10 birds per treatment. During the experimental period, growth performance did not differ among treatments (P > 0.05). The additives with mugwort and pine needle showed lower crude fat content of thigh muscle compared with the control (P < 0.05); however, no significant differences were detected for moisture, crude protein and crude ash content of thigh muscle. Compared with the control, total phenol content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were significantly increased (P < 0.05) with the inclusion of mugwort and pine needle powder level in the broilers’ diets, whereas pH values decreased (P < 0.05). Serum cholesterol and triglyceride concentrations were significantly decreased (P < 0.05) by the increased mugwort and pine needle powder level in the diet, except for high density lipoprotein (HDL) cholesterol concentrations. For thigh meat color, inclusion of mugwort and pine needle powder decreased L* and b* values and increased a* values in thigh muscle of broilers compared with the controls (P < 0.05). Overall, the present study indicates the beneficial effect of using 1 or 2% mugwort and pine needle powder in reducing serum cholesterol and improving meat quality.Key words: Mugwort, pine needle powder, serum cholesterol, meat quality

Simulation of particle migration in viscoelastic fluids using the extended finite element method

No abstract

Probiotics as alternatives to antibiotics in treating post-weaning diarrhoea in pigs: Review paper

The use of antibiotics to prevent post-weaning diarrhoea (PWD) in pigs has faced a setback owing to the associated antibiotic resistance in pigs and in the human populace that consumes the pork. In fact, antibiotic resistance that originates from the food chain is estimated to cause around 700,000 deaths globally each year. Consequently, scientists and researchers have suggested possible alternatives to antibiotics in pig diets. The chief of these has been the use of probiotics. The authors reviewed the literature on the use of probiotics as an alternative to antibiotics in treating PWD in pigs. It is clear that because of pathogenic Escherichia coli PWD continues to be a challenge to profitable swine production. The vast number of studies that was reviewed, point to the beneficial effects of probiotic supplementation on reducing the severity and incidence of PWD. However, some studies report inconsistencies to the general hypothesis. The majority of the microorganisms used as probiotics in the studies belong to the genera Lactobacilli, Bacillus, Bifidobacterium, Enterococcus, probiotic Escherichia coli, and Saccharomyces. The review also revealed that the bacterial strains that are used as probiotics are given individually or as combinations of multiple strains, and at various dosages, yielding varied results in each case. Interestingly, the authors observed wide disparities in the onset of probiotic supplementation and duration of the treatment to attain the results. Hence there is a need to standardize supplementation strategies, including dosage, onset and duration of treatment for probiotics. Furthermore, many of the in vivo studies that revealed positive effects of probiotics on diarrhoea and other production parameters were carried out in more controlled environments. The authors therefore suggest that more field studies in more natural and commercial farm settings should be conducted to augment the literature in relation to the use of probiotics as alternatives to antibiotics in treating PWD.Keywords: antimicrobial resistance, directly-fed microorganisms, post-weaning diarrhoea, swine diet

Implantation of bone marrow-derived buffy coat can supplement bone marrow stimulation for articular cartilage repair

SummaryObjectiveBone marrow stimulation (BMS) has been regarded as a first line procedure for repair of articular cartilage. However, repaired cartilage from BMS is known to be unlike that of hyaline cartilage and its inner endurance is not guaranteed. The reason presumably came from a shortage of cartilage-forming cells in blood clots derived by BMS. In order to increase repairable cellularity, the feasibility of autologous bone marrow-derived buffy coat transplantation in repair of large full-thickness cartilage defects was investigated in this study.MethodsRabbits were divided into four groups: the defect remained untreated as a negative control; performance of BMS only (BMS group); BMS followed by supplementation of autologous bone marrow buffy coat (Buffy coat group); transplantation of autologous osteochondral transplantation (AOTS) as a positive control.ResultsRepair of cartilage defects in the Buffy coat group in a rabbit model was more effective than BMS alone and similar to AOTS. Gross findings, histological analysis, histological scoring, immunohistochemistry, and chemical assay demonstrated that supplementation of autologous bone marrow buffy coat after BMS arthroplasty effectively repaired cartilage defects in a rabbit model, and was more effective than BMS arthroplasty alone.ConclusionSupplementation of autologous bone marrow-derived buffy coat in cases of BMS could be a useful clinical protocol for cartilage repair

A Detailed Monte-Carlo Simulation for the Belle TOF System

We have developed a detailed Monte Carlo simulation program for the Belle TOF system. Based on GEANT simulation, it takes account of all physics processes in the TOF scintillation counters and readout electronics. The simulation reproduces very well the performance of the Belle TOF system, including the dE/dx response, the time walk effect, the time resolution, and the hit efficiency due to beam background. In this report, we will describe the Belle TOF simulation program in detail.Comment: To be submitted to NI

Clinical effect of IRT-5 probiotics on immune modulation of autoimmunity or alloimmunity in the eye

Background: Although the relation of the gut microbiota to a development of autoimmune and inflammatory diseases has been investigated in various animal models, there are limited studies that evaluate the effect of probiotics in the autoimmune eye disease. Therefore, we aimed to investigate the effect of IRT-5 probiotics consisting of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus reuteri, Bifidobacterium bifidum, and Streptococcus thermophilus on the autoimmunity of uveitis and dry eye and alloimmunity of corneal transplantation. Methods: Experimental autoimmune uveitis was induced by subcutaneous immunization with interphotoreceptor-binding protein and intraperitoneal injection of pertussis toxin in C57BL/6 (B6) mice. For an autoimmune dry eye model, 12-weeks-old NOD.B10.H2b mice were used. Donor cornea of B6 mice was transplanted into BALB/C mice. IRT-5 probiotics or phosphate buffered saline (PBS) were administered for three weeks immediately after induction of uveitis or transplantation. The inflammation score of the retinal tissues, dry eye manifestations (corneal staining and tear secretion), and graft survival were measured in each model. The changes of T cells were evaluated in drainage lymph nodes using fluorescence-activated cell sorting. Results: Retinal histology score in IRT-5 group of uveitis was lower than that in PBS group (p = 0.045). Ocular staining score was lower (p < 0.0001) and tear secretion was higher (p < 0.0001) in the IRT-5 group of NOD.B10.H2b mice than that in the PBS group. However, the graft survival in the IRT-5 group was not different from those of PBS group. The percentage of regulatory T cells was increased in the IRT-5-treated dry eye models (p = 0.032). The percentage of CD8+IL-17hi (p = 0.027) and CD8+ interferon gamma (IFN��)hi cells (p = 0.022) were significantly decreased in the IRT-5-treated uveitis models and the percentage of CD8+IFN��hi cells was markedly reduced (p = 0.036) in IRT-5-treated dry eye model. Conclusion: Our results suggest that administration of IRT-5 probiotics may modulate clinical manifestations of autoimmunity in the eye, but not on alloimmunity of corneal transplantation. ? 2017 by the authors.112Nsciescopu

Neutron beam test of CsI crystal for dark matter search

We have studied the response of Tl-doped and Na-doped CsI crystals to nuclear recoils and $\gamma$'s below 10 keV. The response of CsI crystals to nuclear recoil was studied with mono-energetic neutrons produced by the $^3$H(p,n)$^3$He reaction. This was compared to the response to Compton electrons scattered by 662 keV $\gamma$-ray. Pulse shape discrimination between the response to these $\gamma$'s and nuclear recoils was studied, and quality factors were estimated. The quenching factors for nuclear recoils were derived for both CsI(Na) and CsI(Tl) crystals.Comment: 21pages, 14figures, submitted to NIM

The molecular systems composed of the charmed mesons in the HSˉ+h.c.H\bar{S}+h.c. doublet

We study the possible heavy molecular states composed of a pair of charm mesons in the H and S doublets. Since the P-wave charm-strange mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ are extremely narrow, the future experimental observation of the possible heavy molecular states composed of $D_s/D_s^\ast$ and $D_{s0}(2317)/D_{s1}(2460)$ may be feasible if they really exist. Especially the possible $J^{PC}=1^{--}$ states may be searched for via the initial state radiation technique.Comment: 42 pages, 4 tables, 31 figures. Improved numerical results and Corrected typos