ABSTRACT
This study investigates a fractional-order time derivative model of non-Newtonian magnetic blood flow in the presence of thermal radiation and body acceleration through an inclined artery. The blood flow is formulated using the Casson fluid model under the control of a uniformly distributed magnetic field and an oscillating pressure gradient. Caputo-Fabrizio's fractional derivative mathematical model was used, along with Laplace transform and the finite Hankel transform technique. Analytical expressions were obtained for the velocity of blood flow, magnetic particle distribution, and temperature profile. These distributions are presented graphically using Mathcad software. The results show that the velocity increases with the time, Reynolds number and Casson fluid parameters, and diminishes when Hartmann number increases. Moreover, fractional parameters, radiation values, and metabolic heat source play an essential role in controlling the blood temperature. More precisely, these results are beneficial for the diagnosis and treatment of certain medical issues.
ABSTRACT
In this paper, we designed and demonstrated a stimuli-responsive hydrogel that mimics the mass diffusion function of the liver. We have controlled the release mechanism using temperature and pH variations. Additive manufacturing technology was used to fabricate the device with nylon (PA-12), using selective laser sintering (SLS). The device has two compartment sections: the lower section handles the thermal management, and feeds temperature-regulated water into the mass transfer section of the upper compartment. The upper chamber has a two-layered serpentine concentric tube; the inner tube carries the temperature-regulated water to the hydrogel using the given pores. Here, the hydrogel is present in order to facilitate the release of the loaded methylene blue (MB) into the fluid. By adjusting the fluid's pH, flow rate, and temperature, the deswelling properties of the hydrogel were examined. The weight of the hydrogel was maximum at 10 mL/min and decreased by 25.29% to 10.12 g for the flow rate of 50 mL/min. The cumulative MB release at 30 °C increased to 47% for the lower flow rate of 10 mL/min, and the cumulative release at 40 °C climbed to 55%, which is 44.7% more than at 30 °C. The MB release rates considerably increased when the pH dropped from 12 to 8, showing that the lower pH had a major impact on the release of MB from the hydrogel. Only 19% of the MB was released at pH 12 after 50 min, and after that, the release rate remained nearly constant. At higher fluid temperatures, the hydrogels lost approximately 80% of their water in just 20 min, compared to a loss of 50% of their water at room temperature. The outcomes of this study may contribute to further developments in artificial organ design.
ABSTRACT
Despite the development of an extensive toolbox of multiscale rarefied flow simulators, such simulations remain challenging due to the significant disparity of collisional and macroscopic spatiotemporal scales. Our study offers a novel and consistent numerical scheme for a coupled treatment of particles advection and collision governed by the BGK evolution, honoring positivity of the velocity distribution. Our method shares its framework, in spirit, with the unified gas kinetic class of multiscale schemes. Yet it provides attractive features for particle-based stochastic simulations, readily implementable to existing direct simulation Monte Carlo codes. Two main innovations are integrated in the presented BGK particle method. The first ingredient is a high-order time integration that can be interpreted probabilistically, independent of the time step size. The next one is identifying modified particle distributions that remain invariant under the advection-relaxation evolution. We demonstrate accuracy and performance of the devised scheme for prototypic gas flows over a wide range of rarefaction parameters. Due to the resulting robustness and flexibility of the devised exponential BGK integrator, the scheme paves the way towards more affordable simulations of large-scale and multiscale rarefied gas phenomena.
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This manuscript is devoted to investigate the mathematical model of fractional-order dynamical system of the recent disease caused by Corona virus. The said disease is known as Corona virus infectious disease (COVID-19). Here we analyze the modified SEIR pandemic fractional order model under nonsingular kernel type derivative introduced by Atangana, Baleanu and Caputo ([Formula: see text]) to investigate the transmission dynamics. For the validity of the proposed model, we establish some qualitative results about existence and uniqueness of solution by using fixed point approach. Further for numerical interpretation and simulations, we utilize Adams-Bashforth method. For numerical investigations, we use some available clinical data of the Wuhan city of China, where the infection initially had been identified. The disease free and pandemic equilibrium points are computed to verify the stability analysis. Also we testify the proposed model through the available data of Pakistan. We also compare the simulated data with the reported real data to demonstrate validity of the numerical scheme and our analysis.
Subject(s)
COVID-19 , Nonlinear Dynamics , Humans , Models, TheoreticalABSTRACT
The effect of poly(lacticcoglycolic acid) (PLGA) on structure, degradation, drug release and mechanical properties of fibrin/pomegranate(F/POM)-based drugeluting scaffolds have been studied comprehensively. METHODS AND MATERIAL: Nanoparticle-fibrin is prepared from thrombin and fibrinogen dissolved in NaOH and HCl. Then pomegranate powder is added to it. Nanoparticles/pom are provided by freeze drying and freeze milling. The 3-D scaffold of poly(lactide-coglycolic acid) (PLGA) was prepared via saltleaching solvent/casting leaching method and impregnated with nanofibrin-pom. Structural and chemical component of the scaffolds were evaluated by transmission and scanning electron microscopy and furrier transmission infrared spectroscopy, respectively. Moreover, the scaffolds were characterized from the degradation rate and drug releasing rate points of view of human Adipose Derive Stem Cells (hADSCs). Cytotoxicity effects of the scaffold were evaluated on hADSCs via MTT assay. RESULTS: The results showed that the size of nanoparticles was about 100 nm. The scaffold had a slow degradation rate and it caused a sustained release pattern of pom. MTT assay indicated that nanoparticles had no cytotoxicity and fibrin-pom nanoparticles increased compressive strength of PLGA/scaffolds dramatically and also caused a proper compressive modulus. CONCLUSIONS: By adding F/POM nanoparticle to PLGA and fabricating a threedimensional nanocomposite scaffold (PLGA/F/POM nanoparticle), special physical and mechanical properties also suitable for drug release and cell behavior were achieved, which makes it suitable for cartilage tissue engineering applications (Tab. 1, Fig. 7, Ref. 53) Keywords: hybrid composites, drug delivery, carrier, nanoparticles, scaffold.
Subject(s)
Nanocomposites , Fibrin , Glycols , Humans , Polylactic Acid-Polyglycolic Acid Copolymer , Pomegranate , Tissue Engineering , Tissue ScaffoldsABSTRACT
BACKGROUND: Pain may be associated with actinic keratosis (AK), intraepidermal carcinoma (IEC) and invasive squamous cell carcinoma (SCC), which may all display high-risk features. AIM: To examine variation in pain frequency associated with these three conditions, and assess their invasive SCC surface diameter, invasion depth, grade of differentiation, presence of acantholysis and perineural invasion (PNI). METHODS: Pain was prospectively recorded for consecutive cases of AK, IEC and SCC from three institutions in Australia during the period 2016-2018. RESULTS: Pain with palpation was recorded with 15.8% of AK (n = 30/190), 15.1% of IEC (n = 345/299) and 29.0% invasive SCC (n = 247/853). Pain without palpation was respectively 1.1% (2/190), 4.0% (12/299) and 6.7% (57/853). Invasive SCC with increased surface diameters and deeper invasion recorded increased pain frequency. Pain did not vary significantly by the grade of differentiation in males. In females, well-differentiated SCC recorded more pain (45.4%; n = 473) than poorly differentiated SCC (9.1%; n = 11). Acantholytic SCC recorded more pain 48.7% (n = 29) than nonacantholytic SCC 35.2% (n = 824). Three out of five cases of PNI recorded pain. Pain intensity was not recorded, which was a limitation. CONCLUSION: Pain presence increases from AK to invasive SCC. Pain was more frequent in invasive SCC with increased surface diameter, deeper invasion, acantholysis and PNI. Pain frequency did not vary between the grades of differentiation in males. In females, pain was less frequent in poorly differentiated than in well-differentiated SCC.
Subject(s)
Acantholysis/complications , Cancer Pain , Carcinoma, Squamous Cell/pathology , Keratosis, Actinic/complications , Pain/etiology , Skin Neoplasms/pathology , Aged , Cancer Pain/classification , Cancer Pain/pathology , Carcinoma, Squamous Cell/complications , Female , Humans , Male , Neoplasm Grading , Neoplasm Invasiveness , Pain Measurement , Prospective Studies , Skin Neoplasms/complicationsABSTRACT
OBJECTIVE: Several psychosocial risk factors have been identified that increase the rate of readmission in heart failure (HF) patients. However, the impact of social isolation (SI) on the rate of readmission is unclear. Therefore, the current review focused on the impact of SI on readmission rates of patients with HF. METHODS: A Medline-based strategy was applied to search PubMed, SCOPUS, Cochrane library, ProQuest, and Embase from inception until November 15, 2018. We performed a meta-analysis and pooled results using random effects model. The primary outcome was the odds ratio of readmission in HF patients suffering from SI. We examined the impact of both perceived and objective SI on readmission rates. We also examined the differences in readmission rates between these concepts. The secondary outcomes were the incidence of readmission and the prevalence of SI. RESULTS: From 3326 titles, 13 studies (nâ¯=â¯6468 participants) were eligible. The mean follow-up period was 13â¯months. The cumulative incidence for HF-related hospital readmission was 35.47% (95% CI: 34.29-36.67). The pooled prevalence ratio (PR, (95% CI)) was 37.31% (36.14-38.49), 31.51% (30.36-32.68), 32.82% (29.90-35.88), and 39.57% (37.73-41.45) for SI, living alone, lack of social support, and poor social network, respectively. SI was associated with a 55% greater risk of hospital readmission in patients with HF (ORâ¯=â¯1.55; 95% CIâ¯=â¯1.39-1.73; pâ¯<â¯.001). Our analysis did not show a significant difference in the rate of hospital readmission between perceived and objective SI. CONCLUSION: SI is prevalent in patients with HF and seems to be consistently linked to hospital readmission in HF patients, regardless of how it is measured. Therefore, it is necessary to develop interventions to reduce the burden of SI in patients with HF.
Subject(s)
Heart Failure/psychology , Observational Studies as Topic , Patient Readmission , Social Isolation , Social Support , Heart Failure/therapy , HumansABSTRACT
Patients on dialysis experience psychological distress, which can impact pain perception. Reduction of stress and anxiety in patients provides psychological resources to cope with their physical condition. We examined the efficacy of relaxation training on stress, anxiety, and pain perception of hemodialysis (HD) patients. eighty HD patients were randomized into two groups (intervention and control). Benson relaxation training was implemented in the intervention group for 15 min twice daily during 4 weeks. Pain perception, stress, and anxiety scale were evaluated before and after intervention. There were significant differences between pain perception, stress, and anxiety levels in case group before and after intervention (P < 0.001) and there was a correlation between pain perception with stress and anxiety. Instructing Benson's relaxation technique is accompanied by reducing pain, stress, and anxiety level of HD patients. Reducing stress and anxiety can provide calmness for the patients so that pursuing medical therapy would be accompanied with more tranquility and low pain intensity. We suggest improving and preventing the patients' psychological problems as well as other chronic disorders through applying nonpharmacological interventions.
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UNLABELLED: The effect of Zataria multiflora Boiss. (Z. multiflora) essential oils (EO) on biogenic amines (BAs) production and microbial counts in Gouda cheese has been investigated. Zataria multiflora was added to milk in different concentrations (0·05, 0·1, 0·2 and 0·4% (v/v)). The BAs (tyramine and histamine) were measured by RP-HPLC, following extraction from the cheese. Various microbiological analyses (aerobic mesophilic bacteria, enterococci, mesophilic lactobacilli, Enterobacteriaceae, lactococci and yeasts) were performed during ripening using the viable plate count method on specific culture media. The overall acceptability of cheeses was investigated by seven panellists. All the samples containing different concentrations of EO were acceptable to the panellists. Also, Gouda cheeses with 0·2% Z. multiflora EO showed the highest acceptability among all the samples. At the end of maturation period, 0·1, 0·2 and 0·4% Z. multiflora EO reduced tyramine and histamine significantly to 5%, 22% and 44% for tyramine and 14%, 29% and 46% for histamine, respectively, when compared to the control group. The increase of Z. multiflora EO concentrations led to further decrease in BAs content and microbial counts. The maximum microbiological reduction was observed in yeasts, and minimum microbiological reduction was seen in Enterobacteriaceae counts. Zataria multiflora EO could be used for reduction of BAs and also as a flavouring agent in Gouda cheese and could contribute to consumers' health. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of biogenic amines in cheese has a serious impact on public health. Besides, there is growing concern about the use of chemical preservatives and the food industry is looking for new natural preservation methods. Zataria multiflora Boiss. essential oil is well known for its antimicrobial effects, and we attempted to reduce biogenic amines formation in Gouda cheese using Z. multiflora Boiss. essential oil as a natural additive. Furthermore, the desirable organoleptic qualities such as flavour, odour, texture and colour were achieved by adding Z. multiflora Boiss. to cheese.
Subject(s)
Bacteria/growth & development , Biogenic Amines/analysis , Cheese/analysis , Cheese/microbiology , Lamiaceae , Oils, Volatile/pharmacology , Yeasts/growth & development , Animals , Biogenic Amines/metabolism , Colony Count, Microbial , Enterobacteriaceae/growth & development , Enterococcus/growth & development , Lactobacillus/growth & development , Lactococcus/growth & development , Milk/microbiology , Oils, Volatile/chemistryABSTRACT
BACKGROUND AND AIM: Ideally, the period of patients admitting in the Emergency Department (ED) should not exceed 6 hours. Prolonged of the patients admitting time affects the ED overcrowding, quality of patient care and patient satisfaction. To evaluate the efficacy of new programs and suggest new strategies to reduce the overcrowding in a typical overcrowded ED of general teaching hospital in Tehran city. MATERIALS AND METHODS: In this descriptive case study, charts of patients held over 24 hours, in Imam Hossein Hospital affiliated to the Shaheed Beheshti Medical University, were reviewed from April 21(rd) on August 23(rd), 2008. RESULTS: Of 15,477 patients, 151 (1%) have been held in the ED over 24 hours. Reasons for this long-stay included:lack of available bed in Intensive Care Unit (ICU) (125 patients), lack of available bed in related wards (18 patients), poor final decision - making by physician (eight patient). CONCLUSION: Long-term stay of patients in ED of teaching hospital is a major problem. The most frequent cause is a limitation of inpatient beds. The long stay time had not been affected by paraclinic procedures, multispecialities involvement or the lack of obvious diagnosis. The following solution is proposed: (1) creation of a holding unit, (2) active inter-facility transfer and (3) governing admittance of patients who need ICU care to related wards.
ABSTRACT
A realistic outflow boundary condition model for pulsatile flow in a compliant vessel is studied by taking into account physiological effects: compliance, resistance, and wave reflection of the downstream vasculature. The new model extends the computational domain with an elastic tube terminated in a rigid contraction. The contraction ratio, the length, and elasticity of the terminal tube can be adjusted to represent effects of the truncated vasculature. Using the wave intensity analysis method, we apply the model to the test cases of a straight vessel and the aorta and find good agreement with the physiological characteristics of blood flow and pressure. The model is suitable for cardiac transient (non-periodic) events and easily employed using so-called black box software.