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Mathematical modeling of nonlinear blood glucose-insulin dynamics with beta cells effect
Get PDFWe consider mathematical modeling of blood glucose-insulin regulatory system with the additional effect of the secreted insulin by the pancreatic beta cells and in the presence of an external energy input to such system. Such modeling system is investigated to determine the time-dependent nonlinear dynamics that take place by the quantities, which represent the glucose and insulin concentrations in the blood, insulin action as well as in the absence or presence of secreted insulin due to the pancreatic beta cells. Using both analytical and numerical procedures, we determine such quantities versus time for both diabetes patients and normal human and for different values of the parameters. We find that the nonlinear effect of the dynamics of the investigated regulatory system increases the values of the insulin action and the glucose and insulin concentrations. In the absence of the beta cells effects, which can correspond to the case of severe type 1 diabetes, the plasma glucose is higher and the insulin action and the insulin concentration are less active than the corresponding ones for the case in the presence of beta cells, which is relevant for type 2 diabetes or moderate type 1 diabetes patients. For the present system, smaller values of the parameters of the model, which represent kinetics of the glucose and insulin action, insulin sensitivity, insulin secretion enhancement and the plasma insulin decay rate, can lead to notably lower values of the glucose concentration. In the presence of the secreted insulin by the pancreatic beta cells the insulin action and the insulin concentration are more effective to reduce the blood glucose, which can help to improve the diabetes patient’s health
Complexity Dynamics of Gumowski-Mira Map
Get PDFIn the context of nonlinear dynamics, interesting dynamic behavior of Gumowski-Mira Map has been noted under various feasible circumstances. Evolutionary phenomena are discussed through the study of bifurcation analysis leading to period-doubling and chaos. The appearance of chaos in the method is identified by plotting Lyapunov characteristic exponents (LCE) and Topological Entropy within certain parameter range. Dynamic Lyapunov Indicator (DLI) has been procured for further identification of regular and chaotic motions of the Gumowski-Mira Map. The numerical results through the indicator DLI clearly demonstrate the behavior of our map. The correlation dimension has been calculated numerically for the dimension of the chaotic attractor
Impatient Customers in an Markovian Queue with Bernoulli Schedule Working Vacation Interruption and Setup Time
Get PDFIn this paper, using probability generating function method, Impatient customers in an Markovian queue with Bernoulli schedule working vacation interruption and setup time is discussed. Customers impatience is due to the servers vacation. During the working vacation period, if there are customers in the queue, the vacation can be interrupted at a service completion instant and the server begins a regular service period with probability (1 - b) or continues the vacation with probability b. We obtain the probability generating functions of the stationary state probabilities, performance measures, sojourn time of a customer and stochastic decomposition of the queue length, waiting time and numerical results
Analysis of MAP/PH/1 Queueing Model with Breakdown, Instantaneous Feedback and Server Vacation
Get PDFIn this article, we analyze a single server queueing model with feedback, a single vacation under Bernoulli schedule, breakdown and repair. The arriving customers follow the Markovian Arrival Process (MAP) and service follow the phase-type distribution. When the server returns from vacation, if there is no one present in the system, the server will wait until the customer’s arrival. When the service completion epoch if the customer is not satisfied then that customer will get the service immediately. Under the steady-state probability vector that the total number of customers are present in the system is probed by the Matrix-analytic method. In our model, the stability condition, some system performance measures are discussed and we have examined the analysis of the busy period. Numerical results and some graphical representation are discussed for the proposed model
On a New Class of Bivariate Survival Distributions Based on the Model of Dependent Lives and its Generalization
Get PDFIn this paper, a new class of survival distributions based on the model of dependent lives and proportional hazard rate family is introduced. This new family of bivariate survival models contains several bivariate lifetime models and is more flexible. The main purpose of this paper is to generalize this family of bivariate survival distributions of dependent lives so that more flexible models can be achieved. These new families of distributions are called the bivariate proportional hazard rate (BPHR) and the bivariate proportional hazard rate-geometric (BPHRG) families, respectively. It is also observed that, if θ = 1, then the BPHR family is a particular state of the BPHRG family. Several features of these new families of distributions such as the multivariate aging properties, the bivariate hazard gradient, and dependency structures are investigated. We design a flexible computational EM algorithm to calculate the maximum likelihood estimation of parameters. Also, several simulation studies are represented to evaluate the efficiency of the EM algorithm. Finally, we analyze three real datasets and compare the BPHRG models with the BPHR models
Biocatalytic reduction of 5-hydroxymethylfurfural to 2,5-furandimethanol using coconut (Cocos nucifera L.) water
No full textThe hexose dehydration product and important renewable feedstock 5-hydroxymethylfurfural can be biocatalytically reduced to 2,5-furandimethanol in 96% yield using coconut (Cocos nucifera L.) water as the biocatalyst at room temperature. The dimer of 5-hydroxymethylfurfural 5,5\u27-[oxybis(methylene)]bis[2-furaldehyde] can also be reduced to the corresponding diol 5,5\u27-[oxybis(methylene)]bis-[2-furanmethanol] using coconut (Cocos nucifera L.) water in 95% yield under similar conditions. This biocatalytic system could be reused in four cycles without an appreciable loss in activity
Agricultural and biomedical applications of chitosan-based nanomaterials
No full textChitosan has emerged as a biodegradable, nontoxic polymer with multiple beneficial applications in the agricultural and biomedical sectors. As nanotechnology has evolved as a promising field, researchers have incorporated chitosan-based nanomaterials in a variety of products to enhance their efficacy and biocompatibility. Moreover, due to its inherent antimicrobial and chelating properties, and the availability of modifiable functional groups, chitosan nanoparticles were also directly used in a variety of applications. In this review, the use of chitosan-based nanomaterials in agricultural and biomedical fields related to the management of abiotic stress in plants, water availability for crops, controlling foodborne pathogens, and cancer photothermal therapy is discussed, with some insights into the possible mechanisms of action. Additionally, the toxicity arising from the accumulation of these nanomaterials in biological systems and future research avenues that had gained limited attention from the scientific community are discussed here. Overall, chitosan-based nanomaterials show promising characteristics for sustainable agricultural practices and effective healthcare in an eco-friendly manner
Perception of and risk factors for type 2 diabetes among students attending an upstate New York college: A pilot study
No full textBackground: Detecting early type 2 diabetes (T2D) risk factors may reduce or prevent the development of the disease. We conducted a pilot study to generate preliminary data on the perception of T2D and further determined the prevalence of T2D risk factors among college students at an upstate New York campus. Methods: Metabolic profiles were available for 44 college students for cross-sectional analysis. The American Diabetes Association screening guidelines were used to determine risk factors, and perceived susceptibility, perceived seriousness, and self-efficacy were determined with the Health Belief Model\u27s constructs. Sociodemographic and anthropometric data, nutrition knowledge, and metabolic profiles were obtained. Results: The most common T2D risk factors were lack of physical activity (61.4%), decreased high-density lipoprotein cholesterol (HDL-c, 56.8%), high fasting blood glucose (FBG, 45.5%), family history of T2D (43.2%), increased body mass index (BMI, 36.4%), and high blood pressure (15.9%). A high proportion (70%) of participants with detected impaired FBG perceived they were at low risk of developing T2D. Participants with a family history of T2D (mean rank = 24.2) perceived the seriousness of T2D at a similar level as those without family history (mean rank = 21.2), with no significant difference (U = 205, P = 0.430). Nearly 30% of students did not feel confident they could prevent the development of T2D. Pearson\u27s correlations revealed direct relationships between perceived risk of T2D and BMI (r = 0.49, P = 0.001), fat mass percent (r = 0.51, P \u3c 0.001), and waist circumference (r = 0.42, P = 0.005), and an inverse relationship was found with HDL-c (r = - 0.41, P = 0.005). The association of perceived risk of T2D with a family history of T2D revealed a trend toward significance (Chi-squared = 5.746, P = 0.057), and the association of perceived risk of T2D with physical activity was not significant (Chi-squared = 1.520, P = 0.468). The nutrition knowledge score was 74.32 ± 15.97 (recommended is \u3e 75). However, knowledge scores regarding recommended intake of fruits, vegetables, high sodium foods, and whole grains to prevent T2D were only 36.36%, 34.09%, 47.73%, and 63.6%, respectively. Conclusions: The discordance between college students\u27 perceived risk and prevalence of T2D risk factors warrants strategies to address misperceptions of T2D risk and improve lifestyle behaviors among this study sample
Protein signatures of seminal plasma from bulls with contrasting frozen-thawed sperm viability
No full textThe present study investigated the seminal plasma proteome of Holstein bulls with low (LF; n = 6) and high (HF; n = 8) sperm freezability. The percentage of viable frozen-thawed sperm (%ViableSperm) determined by flow cytometry varied from -2.2 in LF to + 7.8 in HF bulls, as compared to the average %ViableSperm (54.7%) measured in an 860-sire population. Seminal proteins were analyzed by label free mass spectrometry, with the support of statistical and bioinformatics analyses. This approach identified 1,445 proteins, associated with protein folding, cell–cell adhesion, NADH dehydrogenase activity, ATP-binding, proteasome complex, among other processes. There were 338 seminal proteins differentially expressed (p \u3c 0.05) in LF and HF bulls. Based on multivariate analysis, BSP5 and seminal ribonuclease defined the HF phenotype, while spermadhesin-1, gelsolin, tubulins, glyceraldehyde-3-phosphate dehydrogenase, calmodulin, ATP synthase, sperm equatorial segment protein 1, peroxiredoxin-5, secretoglobin family 1D and glucose-6-phosphate isomerase characterized the LF phenotype. Regression models indicated that %ViableSperm of bulls was related to seminal plasma peroxiredoxin-5, spermadhesin-1 and the spermadhesin-1 × BSP5 interaction (R2 = 0.84 and 0.79; p \u3c 0.05). This report is the largest dataset of bovine seminal plasma proteins. Specific proteins of the non-cellular microenvironment of semen are potential markers of sperm cryotolerance
Cellular and Functional Physiopathology of Bull Sperm With Altered Sperm Freezability
No full textThe objective of this study was to ascertain the cellular and functional parameters as well as ROS related changes in sperm from bulls with varied sperm freezability phenotypes. Using principal component analysis (PCA), the variables were reduced to two principal components, of which PC1 explained 48% of the variance, and PC2 explained 24% of the variance, and clustered animals into two distinct groups of good freezability (GF) and poor freezability (PF). In ROS associated pathophysiology, there were more dead superoxide anion positive (Dead SO+) sperm in GF bulls than those in PF (15.72 and 12.00%; P = 0.024), and that Dead SO+ and live hydrogen positive cells (live H2O2+) were positively correlated with freezability, respectively (R2 = 0.55, P \u3c 0.0130) and (rs = 0.63, P = 0.0498). Related to sperm functional integrity, sperm from PF bulls had greater dead intact acrosome (DIAC) than those from GF bulls (26.29 and 16.10%; P = 0.028) whereas sperm from GF bulls tended to have greater live intact acrosome (LIAC) than those from PF bulls (64.47 and 50.05%; P = 0.084). Sperm with dead reacted acrosome (DRAC) in PF bulls were greater compared to those in GF (19.27 and 11.48%; P = 0.007). While DIAC (R2 = 0.56, P = 0.0124) and DRAC (R2 = 0.57, P \u3c 0.0111) were negatively correlated with freezability phenotype, LIAC (R2 = 0.36, P = 0.0628) was positively correlated. Protamine deficiency (PRM) was similar between sperm from GF and PF bulls (7.20 and 0.64%; P = 0.206) and (rs = 0.70, P = 0.0251) was correlated with freezability. Sperm characteristics associated with cryotolerance are important for advancing both fundamental andrology and assisted reproductive technologies across mammals